[Infolix] [LABOLIX] Thesis defence - Boris Golden

Dear all, I have the great pleasure to invite you to my thesis defence. It will take place on Monday, 13th May, at 2pm, in Amphi Becquerel. The title is: A unified formalism for complex systems architecture. You will find below the abstract of my PhD thesis. You are also invited to the cocktail that will follow :-) Shall you need any more information, please do not hesitate to contact me! Kind regards, Boris ---------------- Abstract Complex industrial systems are typically artificial objects designed by men, involving a huge number of heterogeneous components (e.g. hardware, software, or human organizations) working together to perform a mission. In this thesis, we are interested in modeling the functional behavior of such systems, and their integration. We will model real systems as functional blackboxes (with an internal state), whose structure and behaviors can be described by the recursive integration of heterogeneous smaller subsystems. Our purpose is to give a unified and minimalist semantics for heterogeneous integrated systems and their integration. By "unified", we mean that we propose a unified model of real systems that can describe the functional behavior of heterogeneous systems and that is closed under integration. By "minimalist" we mean that our formalization intends to provide a small number of concepts and operators to model the behaviors and the integration of complex industrial systems. Our work thus allows to give a relevant formal semantics to concepts and models typically used in Systems Engineering. In this framework, the integration of real systems can be modeled as a recursive process consisting in alternating composition and abstraction, to build a target overall system from elementary systems recursively composed and abstracted at different levels. Based on these definitions of systems and their integration, a minimalist systems architecture framework allows to deal with requirements, systems structure and underspecification during the design. In this thesis, we first define heterogeneous dataflows, and then systems as step-by-step machines transforming dataflows. Such systems can be integrated using operators, to build more complex systems, so that we can handle the two dimensions of the complexity (heterogeneity and integration). We then introduce a minimalist formalism for systems architecture to model requirements, underspecification & structure of systems through the design process. We finally open perspectives around systems optimization when fairness is required.

2013-05-13

[Infolix] [gdr-im] Postdoc and PhD positions in Computational Geometry, Computer Graphics and Image Processing

===================================================================== Postdoc and PhD positions in computer graphics / image processing Location: INRIA / Ecole Polytechnique Start date: May - September 2013 ===================================================================== Description: One postdoc and one PhD position are available at INRIA Saclay (Geometrica team) and Ecole Polytechnique (LIX), France, supported by the Google Faculty Research Award: "Joint Analysis of Images and 3d Shapes" and a French Ministry of Defense (DGA) grant. The goal of this project is to study the interaction between 3d and image data with particular emphasis on creating methods for matching and comparison of 3d models to images. The ultimate goal is to develop a unified framework, both theoretical and practical, for heterogeneous data processing. The ideal candidate should have strong backgrounds in at least one of the following: - Computer graphics and 3d data analysis - Computer vision and image processing - Knowledge of basic differential geometry - Programming experience, especially in multimedia data analysis. For the postdoc position, candidates must have a PhD at the starting time of the post-doc. The expected duration of the post-doc is 1 year. For the PhD position, the candidate should have a master's degree with preference given to those having strong research experience. The expected duration of the PhD is 3 years. Venue and supervision: Successful candidates will be based in INRIA / Ecole Polytechnique located in Palaiseau, Paris area, France. The project will be supervised by Maks Ovsjanikov (Ecole Polytechnique, LIX) and Frederic Chazal (INRIA, Geometrica). How to apply: To apply, contact Maks Ovsjanikov (maks@hidemymail) or Frederic Chazal (frederic.chazal@hidemymail). Please include your CV, a short cover letter and a publication list. Reference letters are optional but may need to be provided upon request.

2013-05-06

[Infolix] Comete-Parsifal Seminar - Mon April 29, 14:30 hs - "Securely Accessing Shared Resources with Concurrent Constraint Programming"

Comete-Parsifal Seminar Monday, April 29th - 14:30 hs LIX - Bâtiment Alan Turing Salle 2017 - Philippe Flajolet Title: Securely Accessing Shared Resources with Concurrent Constraint Programming Speaker: Francesco Santini Abstract: We present a fine-grained security model to enforce the access control on the shared constraint store in Concurrent Constraint Programming (CCP) languages. We show the model for a nonmonotonic version of Soft CCP (SCCP), that is an extension of CCP where the constraints have a preference level associated with them. Crisp constraints can be modeled in the same framework as well. In the considered nonmonotonic soft version (NmSCCP), it is also possible to remove constraints from the store. The language can be used for coordinating agents on a common store of information that represents the set of shared resources. In such scenarios, it is clearly important to enforce the integrity and confidentiality rights on the resources, in order, for instance, to hide part of the information to some agents, or to prevent an agent to consume too many resources.

2013-04-29

[Infolix]GT Combi du LIX - lundi 22/4 à 11h - Alfredo Hubard

Bonjour, Le prochain GT Combi du LIX aura lieu ce lundi 22 avril 2013 à 11h dans la salle Philippe Flajolet. Alfredo Hubard (DI, ENS) nous parlera de "Happing ending theorems for planar convex bodies". Le résumé est disponible ci-dessous. Le programme du GT Combi du LIX est disponible sur le site web de l'équipe : http://www.lix.polytechnique.fr/combi/#seminaire À lundi, Marie et Vincent *************** Orateur : Alfredo Hubard (DI, ENS) Titre : Happing ending theorems for planar convex bodies Résumé : The Erdos-Szekeres (happy ending) theorem claims that, for any number n there is a number ES(n) such that among any set of at least ES(n) points in general position in the plane, there are at least n of them that form the vertex set of a convex polygon. During the last 80 years the value of ES(n) has generated a lot of interest and it remains unknown. Goodman and Pollack generalized this result to the realm of pseudoline arrangements while Bisztriczky and Fejes Toth first, and then, in more generality, Pach and Toth generalized this result to the context of arrangements of convex bodies in the plane. Denote the values of the corresponding Ramsey functions by GP(n) (pseudo lines), BFT(n) (disjoint convex bodies) and PT(n) (non crossing convex bodies) which are all unknown. In a joint work with Andreas Holmsen and Michael Dobbins we showed that the happy ending problem for pseudoline arrangements and for noncrossing convex bodies are equivalent, yielding the equality PT(n)=GP(n) and significant quantitative improvements to the upper bounds of functions BTF(n) and PT(n). The new bounds for GP(n), BFT(n) and PT(n) are the same as the known one for ES(n). ***************

2013-04-22

[Infolix]GT Combi du LIX - lundi 15/4 à 11h - Lionel Pournin

Bonjour, Le prochain GT Combi du LIX aura lieu ce lundi 15 avril à 11h dans la salle Philippe Flajolet. Lionel Pournin (EFREI) nous parlera des "Diamètres des associaèdres". Le résumé est disponible ci-dessous. Le programme du GT Combi du LIX est disponible sur le site web de l'équipe : http://www.lix.polytechnique.fr/combi/#seminaire À lundi, Marie et Vincent *************** Orateur : Lionel Pournin (EFREI) Titre : The diameters of associahedra Résumé : Associahedra are polytopes that were independently discovered within different areas of mathematics such as algebraic topology, discrete geometry, and combinatorial optimization. The boundary complex of the d-dimensional associahedron can be indifferently represented using bracketed words of d+2 letters, triangulations of convex polygons with d+3 vertices, or size d+1 binary trees. In 1988, Daniel Sleator, Robert Tarjan, and William Thurston have shown that the diameter of this polytope is at most 2d-4 when d is larger than 9 and that this bound holds with equality when d is large enough. They further conjecture that "large enough" means "greater than 9". The recently announced proof of this conjecture will be sketched in this talk. As a preliminary, the associahedra will be described as well as a selection of the many problems these polytopes are related to. ***************

2013-04-15

[Infolix] GT Combi du LIX - lundi 8/4 à 11h - Frédéric Meunier

Bonjour, Le prochain GT Combi du LIX aura lieu ce lundi 8 avril 2013 à 11h dans la salle Philippe Flajolet. Frédéric Meunier (Cermics, ENPC) nous parlera d' "Un cadre combinatoire pour la profondeur simpliciale colorée". Le résumé est disponible ci-dessous. Le programme du GT Combi du LIX est disponible sur le site web de l'équipe : http://www.lix.polytechnique.fr/combi/#seminaire À mercredi, Marie et Vincent *************** Orateur : Frédéric Meunier (Cermics, ENPC) Titre : Un cadre combinatoire pour la profondeur simpliciale colorée Résumé : Le théorème de Carathéodory coloré, dû à Bárány, affirme que si l'on se donne d+1 ensembles de points S_1,...,S_{d+1} dans R^d, chacun d'eux contenant l'origine dans son enveloppe convexe, alors il est possible de choisir un point p_i dans chaque S_i et d'avoir encore l'origine dans l'enveloppe convexe des p_i. L'enveloppe convexe des p_i est alors appelée "simplexe coloré contenant l'origine". Le nombre de simplexes colorés contenant l'origine est la "profondeur simpliciale colorée" de l'origine. Une question qui a reçu une attention particulière est celle de savoir quelle est la plus petite profondeur simpliciale colorée possible dans le cas où chaque S_i est de cardinalité d+1. Le théorème de Bárány montre qu'elle vaut au moins 1. La valeur minimale mu(d) qu'elle peut prendre a été étudiée par Deza et al., Bárány et Matoušek, et Stephen et Thomas, qui ont montré que mu(d) vaut toujours au moins (d2+2d+1)/2 et au plus d2+1. La conjecture que mu(d) vaut d2+1 a été vérifiée en dimensions 1, 2 et 3. Dans cet exposé, nous améliorons la borne inférieure et montrons que mu(d) vaut toujours au moins (d2+7d-16)/2. Nous montrons également que mu(4)=17, et donc que la conjecture est vraie en dimension 4. Les preuves utilisent des hypergraphes particuliers spécialement conçus pour ce problème - les systèmes octaédriques, dont l'étude a été récemment suggérée par Bárány. Quelques résultats théoriques les concernant seront également présentés. ***************

2013-04-08

[Infolix]GT Combi du LIX - lundi 8/4 à 11h - Frédéric Meunier

2013-04-08

[Infolix]Soutenance de thèse de Nicolas Guenot

Début du message réexpédié : > De : nicolas guenot > Objet : [LABOLIX] soutenance de thèse > Date : 5 avril 2013 10:55:29 UTC+02:00 > À : labolix@hidemymail > > Bonjour, > > j'ai le plaisir de vous inviter à la soutenance de ma thèse intitulée > > " Nested Deduction in Logical Foundations for Computation " > > qui aura lieu le mercredi 10 avril 2013 à 14h à l'Ecole Polytechnique, > en salle Gilles Kahn dans le Bâtiment Turing. Des instructions pour > venir sont accessibles ici: > > http://www.inria.fr/en/centre/saclay/overview/practical-info/how-to-reach-the-centre > > La soutenance sera suivie d'un pot auquel vous êtes également conviés. > Le jury sera composé de Delia Kesner, Richard McKinley, Dale Miller, > Luca Roversi, Lutz Strassburger et Benjamin Werner. > > > Résumé: > > Dans cette thèse, nous étudions différentes approches permettant > de donner un contenu calculatoire à des systèmes logiques suivant > le principe d'inférence profonde, qui généralisent les formalismes > traditionnels (tels que la déduction naturelles et le calcul des > séquents) en autorisant l'application de règles d'inférence à > n'importe quelle position dans une formule. Tout d'abord, nous > suivons l'approche de la correspondence de Curry-Howard, en > définissant des systèmes d'inférence profonde pour la logique > intuitionniste, notamment dans le calcul des structures, et en > décrivant une procédure de normalisation purement syntaxique. > Ceci permet d'intépréter les preuves d'un tel système comme des > lambda-termes et de connecter la normalisation à la réduction dans > un lambda-calcul avec substitutions explicites. En particulier, > nous étudions les extensions du lambda-calcul qui peuvent être > obtenues en exploitant les particularités de nos systèmes logiques. > Enfin, nous considérons la recherche de preuve comme calcul, en > particulier à travers l'adaptation de la technique de focalisation > (en logique linéaire) au calcul des structures, qui permet de réduire > drastiquement le non-déterminisme de la construction de preuves. > Nous montrons également comment la recherche de preuve en logique > intuitionniste peut être reliée à la réduction dans le lambda-calcul > avec substitutions explicites. > > > Cordialement, > > -nicolas >

2013-04-05

[Infolix] Comete-Parsifal Seminar - Thu April 04, 15:00 hs - "Toward Intelligent Location-Privacy Preserving Mechanisms"

Comete-Parsifal Seminar Thursday, April 4th - 15:00 hs LIX - Bâtiment Alan Turing Salle 2017 - Philippe Flajolet Title: Toward Intelligent Location-Privacy Preserving Mechanisms Speaker: Reza Shokri Abstract: The widespread use of smart mobile devices has fostered the development of a variety of successful data-sharing mobile applications. The data that users disclose to untrusted entities (for example, through location-based services) exposes aspects of their private life, which is not apparent at first but can be inferred from the revealed data. People are notoriously bad estimators of risks, including privacy risks. Moreover, due to various cognitive biases, lack of enough information, and the complexity of the decision problem, it is difficult for users to make the optimal decision about whether to reveal or obfuscate their information and, if necessary, how to obfuscate it. In this talk, I address the problem of protecting users' privacy in data-sharing mobile applications, with the focus on location-based services. I propose strategic algorithms and intelligent tools to automatically assess the users' location-privacy level, and to find the right balance between revealing and hiding their data. I will present the Location-Privacy Meter (LPM) tool, that we developed to quantify location privacy, as well as our work on optimal defense mechanisms against location-inference attacks. More information: http://people.epfl.ch/reza.shokri

2013-04-04

[Infolix] REMINDER: Comete-Parsifal Seminar - Thu April 04, 15:00 hs - "Toward Intelligent Location-Privacy Preserving Mechanisms"

2013-04-04

GT Combi du LIX - lundi 25/3 à 11h - Razvan Gurau

Bonjour, Le prochain GT Combi du LIX aura lieu ce lundi 25 mars 2013 à 11h dans la salle Philippe Flajolet. Razvan Gurau (CPHT) nous parlera de "Graphes colorés et triangulations en dimension supérieure à deux". Le résumé est disponible ci-dessous. Le programme du GT Combi du LIX est disponible sur le site web de l'équipe : http://www.lix.polytechnique.fr/combi/#seminaire À mercredi, Marie et Vincent *************** Orateur : Razvan Gurau (CPHT) Titre : Graphes colorés et triangulations en dimension supérieure à deux Résumé : Les graphes à lignes colorés encodent des triangulations d'espaces en dimension arbitraire. On détaillera cette relation et on étudiera notamment une sous-catégorie de graphes qui sont de genre zéro pour un ensemble canonique de projections planaires. Ces graphes représentent topologiquement des sphères et dominent le comportement de modèles de grands tenseurs aléatoires. ***************

2013-03-25

Postdoc and PhD positions in computer graphics, image processing and geometric data analysis

===================================================================== Postdoc and PhD positions in computer graphics / image processing Location: INRIA (Geometrica) / Ecole Polytechnique (LIX) Start date: May - September 2013 ===================================================================== Description: One postdoc and one PhD position are available at INRIA Saclay (Geometrica team) and Ecole Polytechnique (LIX), France, supported by the Google Faculty Research Award: "Joint Analysis of Images and 3d Shapes" and a French Ministry of Defense (DGA) grant. The goal of this project is to study the interaction between 3d and image data with particular emphasis on creating methods for matching and comparison of 3d models to images. The ultimate goal is to develop a unified framework, both theoretical and practical, for heterogeneous data processing. The ideal candidate should have strong backgrounds in at least one of the following: - Computer graphics and 3d data analysis - Computer vision and image processing - Knowledge of basic differential geometry - Programming experience, especially in multimedia data analysis. For the postdoc position, candidates must have a PhD at the starting time of the post-doc. The expected duration of the post-doc is 1 year. For the PhD position, the candidate should have a master's degree with preference given to those having strong research experience. The expected duration of the PhD is 3 years. Venue and supervision: Successful candidates will be based in INRIA / Ecole Polytechnique located in Palaiseau, Paris area, France. The project will be supervised by Maks Ovsjanikov (Ecole Polytechnique, LIX) and Frederic Chazal (INRIA, Geometrica). How to apply: To apply, contact Maks Ovsjanikov (maks@hidemymail) or Frederic Chazal (frederic.chazal@hidemymail). Please include your CV, a short cover letter and a publication list. Reference letters are optional but may need to be provided upon request.

2013-03-25

GT Combi du LIX - lundi 25/3 à 11h - Razvan Gurau

2013-03-20

GT Combi du LIX - mercredi 20/3 à 11h - Jarek Rossignac

Bonjour, Le prochain GT Combi du LIX aura lieu ce mercredi 20 mars 2013 (**) à 11h dans la salle Philippe Flajolet. Jarek Rossignac (Georgia Tech) nous parlera de "Advances and challenges in the design of compact representations of meshes and complexes". Le résumé est disponible ci-dessous. ** Notez bien le jour inhabituel ! ** Le programme du GT Combi du LIX est disponible sur le site web de l'équipe : http://www.lix.polytechnique.fr/combi/#seminaire À mercredi, Marie et Vincent *************** Orateur : Jarek Rossignac (Georgia Tech, School of Interactive Computing) Titre : Advances and challenges in the design of compact representations of meshes and complexes Résumé : The lecture will address recent advances in compact representations of triangle meshes and their extensions to polygon and tetrahedron meshes and to simplicial complexes. We define a core set of Random Access and Traversal operators and discuss their desired features of Constant Amortized Time, Editability, and Streamability. We couch our discussion in terms of corners [1] and start with the Corner Table data structure [1] which stores for each triangle 3 references to its vertices and 3 references to asjacent triangles and hence uses 6 rpt (integer references per triangle) or equivalently 192 bpt (bits per triangle). By matching each vertex with a different triangle, the SOT approach [2] eliminates the need to store the references form triangles to their vertices. By matching most vertices with an incident quad (pair of adjacent incident triangles), the SQuad approach [3] eliminates about one third of the remaining references to adjacent triangles. By finding an arrangements of the quads so that their diagonals form a loop that is a nearly Hamiltonian cycle of the mesh, the LR approach [4] (and its BELR variation) reduce storage cost to about 1 rpt (and respectively to about 26 bpt). By gap encoding the references of the LR representation, the Zipper approach [5] further reduces storage to about 6 bpt, yet it supports the same Constant Amortized Time Random Access and Traversal operators as the Corner Table. Unfortunately, these compact data structures are neither editable (i.e., they do not support local changes to the connectivity, such as an edge flip or collapse, in constant amortized time) nor streamable (i.e., they cannot be efficiently constructed from a streamed input format nor processed in streamed mode when the file is larger than the available core memory). The ESQ approach [6] offers an editable and more general version of SQuad. The Grouper approach [7] offers a streamable version of SQuad. The SOT approach has also been extended to tetrahedron meshes [8]. It extends to concept of triangle corners to tetrahedron wedges and offers convenient wedge operators for mesh traversal. 1. “Edgebreaker on a Corner Table: A simple technique for representing and compressing triangulated surfaces”, J. Rossignac, A. Safonova, A. Szymczak. Book chapter in Hierarchical and Geometrical Methods in Scientific Visualization, Farin, G., Hagen, H. and Hamann, B., eds. Springer-Verlag, Heidelberg, Germany. Pages 41-50, January 2003. 2. “SOT: Compact Representation for Triangle and Tetrahedral Meshes”, T. Gurung and J. Rossignac, Georgia Institute of Technology, SIC Technical Report GT-IC-10-01, 2010 https://smartech.gatech.edu/handle/1853/35001 3. “SQuad: Compact Representation for Triangle Meshes”, T. Gurung, D. Laney (LLNL), P. Lindstrom (LLNL), and J. Rossignac. Eurographics 2011. Published as a journal paper in the Computer Graphics Forum Journal (CGF) 30(2): 355-364. 4. “LR: Compact connectivity representation for triangle meshes”, Topraj Gurung, Peter Lindstrom, Mark Luffel, Jarek Rossignac. ACM SIGGRAPH 2011. Published as a journal paper in the ACM Transactions on Graphics (TOG), 30(4): 67, August 2011. 5. “Zipper: A compact connectivity data structure for triangle meshes”, T. Gurung, M. Luffel, P. Lindstrom, and J. Rossignac. ACM Symposium on Solid and Physical Modeling, October 2012. Journal of Computer-Aided Design. 45(2): 262-269 (2013). 6. “ESQ: Editable SQuad representation for triangle meshes”, L. Castelli Aleardi, O. Devillers, J. Rossignac. IEEE sponsored Conference on Graphics, Patterns and Images (SIBGRAPI), August 22, 2012, Brazil. 7. “Grouper: A compact, streamable triangle mesh data structure” M. Luffel, R. Gurung, P. Lindstrom, and J. Rossignac, submitted 2012. 8. “SOT: Compact representation for Tetrahedral Meshes”, T. Gurung and J. Rossignac. ACM Symposium on Solid and Physical Modeling (SPM), 79-88. 2009. ***************

2013-03-18

Postdocs available in Proof Certificates

One or two postdoctoral positions are available within the Parsifal team, a joint research team between INRIA Saclay and the Laboratoire d’Informatique (LIX) on the campus of Ecole Polytechnique. Successful candidates will help with designing, implementing, and experimentally validating the design of proof certificates for a range of theorem provers in intuitionistic and classical logic and arithmetic. These positions are for one year, with a second year extension possible. Candidates should start in Fall 2013. These positions are funded by ProofCert, an ERC Advanced Grant with the goal of designing a format for proof certificates that can capture the proof evidence within all major theorem provers while also being checkable by a simple, declarative proof checker. This format must allow treating some inference steps as (non-deterministic) computation as well as supporting (bounded) proof reconstruction. The ideal candidate should have strong backgrounds in - basic proof theory (in particular, the sequent calculus); - various automated and interactive theorem proving systems (particularly those involving induction); and - programming in logic programming (Prolog or lambda Prolog) as well as other high-level programming languages (such as ML or Haskell). Venue Employed postdocs will be members of the INRIA Parsifal team which is located in the Laboratoire d’Informatique (LIX) on the campus of Ecole Polytechnique. This campus is situated to the south of Paris and is an easy commute from Paris on the RER B regional train line. French proficiency is not a requirement. Application Candidates must have a Ph.D.; if the Ph.D. thesis is not yet defended when the application is made, the candidate should provide the planned defense date and the composition of the thesis committee. To apply, contact Dale Miller (dale.miller@hidemymail) and include a cover letter and (links to) your CV and publication list. Additional material, such as letters of recommendation, will be requested if necessary. Early expression of interest is encouraged. We plan to make a decision on this position in mid-April 2013. More Information Further information regarding ProofCert and the Parsifal team can be found at the following urls. - The ERC Advanced Grant ProofCert: http://team.inria.fr/parsifal/proofcert/ - The INRIA Parsifal team: http://team.inria.fr/parsifal/ - Positions offered by Parsifal in 2013: http://team.inria.fr/parsifal/positions/ - Miller's web page: http://www.lix.polytechnique.fr/Labo/Dale.Miller/

2013-03-15

Séminaire des doctorants

Bonjour à tous, Le séminaire de ce vendredi sera présenté par Amaury Pouly de l'équipe Ateam. Il aura lieu à 10h en salle Schützenberger et sera précédé d'un petit déjeuner. Title: Continuous models of computations, complexity of real functions, complexity of solving polynomial ordinary differential equations In this presentation I will talk about various aspects of my PhD thesis, mostly related to the study of a continous model of computation called the General Purpose Analog Computer (GPAC). This model was introduced by Claude Shanon even before the invention of the transistor and was one of the first computer ever made. Based on differential equations, it features continuous time and space, providing a different approach to computability. It is interesting to study the relationship between this model and other classical models of computation. I will explain what is known about its relationship to Turing Machines and we will see that it is closely related to the theory of real computable functions (Computable Analysis). We will see that those models are mostly equivalent from a computability point of view. I am studying this equivalence from a complexity point of view. I will show how we can define a complexity measure on the GPAC and how it could relate to the complexity theory of Computable Analysis. On one side, I will explain how one can efficiently simulate a Turing Machine with differential equations. On the other side, I will talk about the complexity of solving differential equations, which is also an interesting subject by its own. Désolée pour cette annonce tardive, À vendredi Claire Lucas

2013-03-13

Talk by Danko Ilik, 19 March 2013

Danko Ilik will be visiting the Parsifal team during 19 March 2013. He will give a talk immediately after lunch. Best wishes, -Dale Control operators as constructive extensions of intuitionistic logic Speaker: Danko Ilik Venue: Salle Philippe Flajolet, LIX, Alan Turing Building Date: 19 March 2013, 13h30 Since the observations of Felleisen and Griffin, in the early 1990s, that control operators from the theory of programming languages can be used to extend the Curry-Howard correspondence from intuitionistic to classical logic, these operators (and, by extrapolation, computational side-effects) have been taught of as non-constructive. Yet, in recent works of Herbelin and the author, it has been shown that constructive logical systems, weaker than classical logic, and stronger than intuitionistic logic, can be built using them. In this talk, I will survey these systems and discuss some of their recent applications and meta-mathematical implications, like the provability of Open Induction on Cantor space, or the status of the arithmetical Church’s Thesis.

2013-03-13

Postdoc position on mathematics of constraint satisfaction in Paris

----------------------------------------------------------------------------------------- Postdoc position on mathematics of constraint satisfaction in Paris ----------------------------------------------------------------------------------------- A postdoc position is available at LIX, Ecole Polytechnique, France, supported by the ERC Starting Grant CSP-Complexity: "Constraint Satisfaction Problems: Algorithms and Complexity" held by Manuel Bodirsky. The goal of the project is to systematically study the computational complexity of CSPs for constraint languages over infinite domains. Requirements are a PhD degree in Computer Science or Mathematics, and strong background in complexity, universal algebra, or model theory. The postdoc will be employed by the CNRS and will receive around 2000 euros, free of charges, per month. The position will be for one year with the possibility of a prolongation by another year; the starting date is flexible. There are no teaching obligations, but researchers will have the opportunity to interact with students in the context of their projects. There is generous travel support. Applications should be sent in electronic form, including a CV, publication list, motivation letter, and a copy or summary of the PhD thesis, to bodirsky@hidemymail. The review of applications begins immediately and continues until the position is filled. Informal inquires by email are welcome.

2013-03-11

Talk by Danko Ilik, 19 March 2013

2013-02-27

Séminaire algorithmique du plateau de Saclay, le vendredi 22 Février 2013

Begin forwarded message: > From: Johanne Cohen > Date: February 12, 2013 1:05:05 PM GMT+01:00 > To: sem-algo-saclay@hidemymail > Cc: Johanne Cohen > Subject: Séminaire algorithmique du plateau de Saclay, le vendredi 22 Février 2013 > > Chers collègues, > > > Le séminaire algorithmique du plateau de Saclay aura lieu le > Vendredi 22 Février 2013 (14h30 -15h30) au LIX salle Gilles Kahn, > bâtiment Alan Turing, Campus de l'École Polytechnique, Palaiseau. > > > Au programme: > Titre : Graph invariants in proof complexity > Exposant : Moritz Mueller > Résumé :An infinity axiom is a satisfiable first-order sentence > without finite models. The fact that it does not have finite models can be > expressed by a sequence of propositional contradictions, and it is an > important issue to understand the proof complexity of these contradictions. > For example, the least number principle does not have short treelike > Resolution refutations, but does have short non-treelike ones. > > Pathwidth and treewidth are well-known graph invariants. We introduce > variations for directed graphs, called ordered pathwidth and ordered > treewidth respectively. We are interested in the ordered treewidth or > ordered pathwidth of the directed acyclic graphs underlying proofs, say, in > Resolution. Roughly speaking, the ordered treewidth measures how close the > proof is to be treelike, and the ordered pathwidth is related to its clause > space. We generalize known time-space lower bounds in two ways, namely > first by relaxing the usual clause space measure to ordered treewidth, and > second by giving such lower bounds in general for infinity axioms. For > example, the least number principle does not have short resolution > refutations of bounded ordered treewidth. > > This is joint work with Stefan Szeider. > > > Bien cordialement > > > Johanne Cohen > > CR CNRS > E-mail: Johanne.Cohen@hidemymail > Phone: + 33 1 39 25 42 20 > address: PRiSM,Université de Versailles > 45, avenue des états-unis > 78035 Versailles Cedex > France > > > > >

2013-02-21

GT Combi du LIX - lundi 25/2 à 11h - Juanjo Rué

Bonjour, Le prochain GT Combi du LIX aura lieu lundi 25 février 2013 à 11h dans la salle Philippe Flajolet. Juanjo Rué (ICMAT, Madrid) nous parlera de "Threshold functions for systems of equations on random sets". Le résumé est disponible ci-dessous. Le programme du GT Combi du LIX est disponible sur le site web de l'équipe : http://www.lix.polytechnique.fr/combi/#seminaire À lundi, Marie et Vincent *************** Orateur : Juanjo Rué (ICMAT, Madrid) Titre : Threshold functions for systems of equations on random sets Résumé : We present a unified framework to deal with threshold functions for the existence of certain combinatorial structures in random sets. More precisely, let Mx = 0 be a linear system of r equations and m variables, and A a random set on [n] where each element is chosen independently with the same probability. We show that, under certain conditions, there exists a threshold function for the property " A^m contains a non-trivial solution of Mx = 0 ", depending only on r and m and, furthermore, we study the behavior of the limiting probability in the threshold scale in terms of volumes of certain convex polytopes arising from the linear system under study. Our results cover several combinatorial families, namely sets without arithmetic progressions of given length, k-sum-free sets, B_h[g] sequences and sets without Hilbert cubes of dimension k, among others. The techniques used in this approach combines the so-called Probabilistic Method, widely used in discrete mathematics, joint with lattice point estimates coming from Ehrhart theory on polytopes. If time permits, further extensions and on-going projects in this direction will be also discussed. This is a joint work with Ana Zumalacárregui. The preprint is available on-line at http://arxiv.org/abs/1212.5496. ***************

2013-02-20

GT Combi du LIX - lundi 18/2 à 12h (**) - Cécile Mailler

Bonjour, Le prochain GT Combi du LIX aura lieu lundi 18 février 2013 à 12h (**) dans la salle Philippe Flajolet. Cécile Mailler (LMV, UVSQ) nous parlera de "formules booléennes aléatoires construites sur un ensemble non borné de variables". Le résumé est disponible ci-dessous. ** Notez bien l'heure inhabituelle ! ** Le programme du GT Combi du LIX est disponible sur le site web de l'équipe : http://www.lix.polytechnique.fr/combi/#seminaire À lundi, Marie et Vincent *************** Orateur : Cécile Mailler (LMV, UVSQ) Titre : Formules booléennes aléatoires construites sur un ensemble non borné de variables Résumé : Un arbre booléen est un arbre binaire, planaire dont les noeuds internes sont étiquetés par des connecteurs logiques (ici ET ou OU), et dont les feuilles sont étiquetées par des littéraux. Si les littéraux sont choisis dans une famille finie $\{x_1,\bar{x}_1,\ldots,x_k,\bar{x}_k\}$, l'arbre booléen calcule une fonction booléenne à $k$ variables. Si l'arbre booléen est tiré uniformément parmi les arbres de taille $n$, on obtient, quand n tend vers l'infini la distribution des grands arbres, définie sur l'espace des fonctions booléennes à $k$ variables. Mais ne serait-il pas plus naturel de choisir ``$k=\infty$'' ou même ``$k = k(n)$'' ? ***************

2013-02-14

Séminaire algorithmique du plateau de Saclay, le vendredi 22 Février 2013

Chers collègues, Le séminaire algorithmique du plateau de Saclay aura lieu le Vendredi 22 Février 2013 (14h30 -15h30) au LIX salle Gilles Kahn, bâtiment Alan Turing, Campus de l'École Polytechnique, Palaiseau. Au programme: Titre : Graph invariants in proof complexity Exposant : Moritz Mueller Résumé :An infinity axiom is a satisfiable first-order sentence without finite models. The fact that it does not have finite models can be expressed by a sequence of propositional contradictions, and it is an important issue to understand the proof complexity of these contradictions. For example, the least number principle does not have short treelike Resolution refutations, but does have short non-treelike ones. Pathwidth and treewidth are well-known graph invariants. We introduce variations for directed graphs, called ordered pathwidth and ordered treewidth respectively. We are interested in the ordered treewidth or ordered pathwidth of the directed acyclic graphs underlying proofs, say, in Resolution. Roughly speaking, the ordered treewidth measures how close the proof is to be treelike, and the ordered pathwidth is related to its clause space. We generalize known time-space lower bounds in two ways, namely first by relaxing the usual clause space measure to ordered treewidth, and second by giving such lower bounds in general for infinity axioms. For example, the least number principle does not have short resolution refutations of bounded ordered treewidth. This is joint work with Stefan Szeider. Bien cordialement Johanne Cohen CR CNRS E-mail: Johanne.Cohen@hidemymail Phone: + 33 1 39 25 42 20 address: PRiSM,Université de Versailles 45, avenue des états-unis 78035 Versailles Cedex France

2013-02-14

A talk by Zena Ariola, 27 Feb 2013, 11h

Zena Ariola (Professor from the University of Oregon) is currently visiting PPS in Paris. She will visit LIX on 27 Feb and give the following talk. Call-by-need: reduction, continuation passing style and abstract machine by Zena Ariola 27 Feb 2013, 11h, Salle Philippe Flajolet, Alan Turing Building INRIA-Saclay & LIX, Ecole Polytechinque We introduce the call-by-need calculus and discuss how it represents Wadsworth's graph reduction. We will then present a continuation-passing style (CPS) transformation which brings to light the fact that call-by-need variables are not given meaning by substitution. We relate this CPS to the pi-calculus. We follow with the classical extension which raises issues regarding the sharing of bindings. Two approaches will be discussed, one inspired by natural deduction and the other by the sequent calculus. One example will show how the two semantics differ.

2013-02-11

[hipercom] Dr. Omprakash Gnawali's talk On the Repeatibility of Wireless Sensor Network Experiments

Abstract: Repeatable experiments are thought to be an essential core of any scientific discipline. In this talk, I will describe the challenges in making sensor networking experiments repeatable. I will then describe the work I and others in the sensor network research community have done to address the repeatibility of network experiments.

Speaker Bio: Omprakash Gnawali is an Assistant Professor at the University of Houston, USA. He was a Postdoctoral Scholar at Stanford University, got his Ph.D. from the University of Southern California, and received his Masters and Bachelors degrees from the Massachusetts Institute of Technology. His research lies at the intersection of low power wireless networks and embedded sensing systems.

2013-02-04

Séminaire des doctorants - Présentation de Tatiana Prosvirnova

Début du message réexpédié : > De : lucas@hidemymail > Objet : [LABOLIX] Séminaire des doctorants - Présentation de Tatiana Prosvirnova > Date : 18 janvier 2013 17:14:52 UTC+01:00 > À : labolix@hidemymail > > Bonjour à tous, > > Le prochain séminaire des doctorants sera présenté par Tatiana Prosvirnova > de l'équipe SYSMO. Il aura lieu vendredi prochain, 25 janvier à 10h en > salle Gilles Kahn. > > Model-based safety assessment: AltaRica 3.0 project > > Model based approach for Safety Analysis is gradually wining the trust of > safety engineers but is still a wide domain of research. > Reliability engineers know very well risk modeling formalisms, such as > ¬ìFailure mode, effects and criticality analysis¬î (FMECA), Fault Trees, > Event trees, Markov Processes, Petri Nets, etc.; and efficient algorithms > and tools are available to study these models. However, despite of their > qualities, these formalisms share a major drawback: models designed with > these formalisms are far from the functional architecture of the system > under study. As a consequence, models are hard to design and to maintain > throughout the life cycle of systems. A small change in the specifications > may require revisiting completely the safety models, which is both > resource consuming and error prone. The high level modeling language > AltaRica has been created to tackle this problem. > The objective of the AltaRica 3.0 project, developed at LIX, is to propose > a new version of AltaRica modeling language and a set of modeling and > assessment tools to perform safety analyses. AltaRica 3.0 is a formal > modeling language, based on Guarded Transition Systems - a > state/transition formalism that generalizes classical safety formalisms, > such as Reliability Block Diagrams, Petri Nets and Markov chains. The > assessment tools for Guarded Transition Systems include compilers to Fault > Trees and Markov chains, stochastic and stepwise simulators, a > model-checker, and a reliability allocation module. > The aim of my talk is, first of all, to give an overview of AltaRica 3.0 > project, then to present AltaRica 3.0 modeling language and Guarded > Transition Systems formalism, and finally to explain the algorithm of > compilation of Guarded Transition Systems into Fault Trees (Boolean > formulae). > > Venez nombreux! > Cordialement, > > Claire Lucas

2013-01-21

[tanc] Two new masters internships available

GRACE is now offering two new masters-level internships: see our Jobs page.

2013-01-18

NSV 2013, 6th edition on Numerical Software Verification, CFP

[my apologizes for multiple postings] CALL FOR PAPERS ************ NSV 2013 ************ 6th Workshop on Numerical Software Verification, A Satellite Workshop of the CPSWeek 2013 Philadelphia, Pennsylvania, USA April 8th 2013 http://www.lix.polytechnique.fr/~ghorbal/NSV-2013/ Important Dates =============== Submissions deadline: Friday, February 1st, 2013, AoE. Notification: February 28th 2013. Final version: March 6th 2013. Description of the workshop =========================== Numerical computations are ubiquitous in cyber-physical systems: supervision, prediction, simulation and signal processing rely heavily on numerical calculus to achieve desired goals. Verification of numerical algorithms has a unique set of challenges, which set it apart from rest of software verification. While verification and validation of software target global properties of the whole system, numerical techniques intrinsically focus on local considerations or approximations of system components. While “ abstracting away ” the data can still give meaningful proofs of correctness for many types of software, in numerical algorithms, such abstractions are unlikely to succeed. The implementation of numerical techniques on modern hardware adds another layer of approximation because of the use of finite representations of infinite precision numbers. Such representations usually lack basic arithmetic properties such as commutativity and associativity, and can cause catastrophic variations in the global system behavior through something as innocuous as a rounding error. It is hence imperative to develop logical and mathematical techniques that would allow reasoning about programmability and reliability in this space. The NSV workshop is dedicated to the current development and the future prospects for such techniques. Topics =============== The topics of the workshop include: - Models and abstraction techniques - Specifications of correctness for numerical programs - Formal specification and verification of numerical programs - Quality of finite precision implementations - Propagation of uncertainties, deterministic and probabilistic models - Numerical properties of control software - Hybrid systems verification - Validation for scientific computing programs - Optimality of program behavior - Tradeoffs between quality of service and resource (for example energy) - consumption in programs - Benchmarks and tools for numerical software verification Submission information ====================== We solicit regular research papers about recent work under the wide umbrella of Numerical Software Verification detailed above. The submission should not exceed 15 pages, Springer LNCS format. We also welcome tool, benchmark and case-studies papers of at most 6 pages. Extended abstract describing work in progress of no more than 5 pages are also highly encouraged. More information about the submission guidelines can on the workshop website. All accepted submissions will be included in the CPSWeek CD-ROM. After the workshop, presenters of selected research papers will be invited to submit an extended version to a special issue about Numerical Software Verification of the journal of Mathematics in Computer Science. Papers should be submitted (as PDF) through easychair https://www.easychair.org/conferences/?conf=nsv2013 Organizers ========== Khalil Ghorbal, Logical Systems Lab, CS Department, Carnegie Mellon University Jyotirmoy V. Deshmukh, Toyota Technical Center All questions about the workshop can be addressed to them via email: Khalil.Ghorbal@hidemymail Jyotirmoy.Deshmukh@hidemymail Program Committee ================== - Khalil Ghorbal Carnegie Mellon University - Jyotirmoy V. Deshmukh Toyota Technical Center - Swarat Chaudhuri Rice University - Sriram Sankaranarayanan University of Colorado, Boulder - Eric Goubault CEA-LIST/École Polytechnique - Sylvie Putot CEA-LIST/École Polytechnique - Franjo Ivančić NEC Laboratories America - Jim Kapinski Toyota Technical Center

2013-01-17

[tanc] News: January 2013

New building; Welcome Nicolas Delfosse and Julia Pieltant; Jérôme Milan departs; ANR Catrel

2013-01-14

Postdoc position in proof theory in LIX

Début du message réexpédié : > De : Lutz Strassburger > Objet : [gdr-im] Postdoc position in proof theory in Paris > Date : 10 janvier 2013 13:35:40 UTC+01:00 > À : Lutz Strassburger > > > > -------------------------------------------------------- > Postdoc position in proof theory in Paris > -------------------------------------------------------- > > There is an opening of a postdoc position on structural and > computational proof theory. The position is financed by > the ANR within the project STRUCTURAL. > > > > The postdoc will be hosted by INRIA and the Laboratoire d'Informatique (LIX) at the Ecole Polytechnique, one of the "Grand Ecoles" in the French university system, located in the suburbs of Paris. > > The successful candidate will be working within the PARSIFAL team. > > > > Starting date should be between February and April 2013. > > Applicants must have a Ph.D. or equivalent in computer science or > mathematics, and should have a strong background in proof theory > and related topics. The principal responsibility of the postdoc > will be to carry out research in the area of proof theory within the > project STRUCTURAL. There are no teaching duties. > > For further information, see > > > or contact > Lutz Strassburger > > Applications should be sent via email to Lutz Strassburger > and should include a CV, a research > statement (1-2 pages), and one or two recommendation letters. The > application deadline is > > *** January 31, 2013 *** > > >

2013-01-14

Postdoc position on mathematics of constraint satisfaction in LIX

Début du message réexpédié : > De : manuel bodirsky > Objet : [gdr-im] Postdoc position on mathematics of constraint satisfaction in Paris > Date : 11 janvier 2013 21:55:35 UTC+01:00 > À : gdr-im@hidemymail > > ----------------------------------------------------------------------------------------- > Postdoc position on mathematics of constraint satisfaction in Paris > ----------------------------------------------------------------------------------------- > > A postdoc position is available at LIX, Ecole Polytechnique, France, supported > by the ERC Starting Grant CSP-Complexity: > "Constraint Satisfaction Problems: Algorithms and Complexity" > held by Manuel Bodirsky. The goal of the project is to systematically > study the computational complexity of CSPs for constraint languages over > infinite domains. > > Requirements are a PhD degree in Computer Science or Mathematics, > and strong background in complexity, universal algebra, or model theory. > > The postdoc will be employed by the CNRS and will receive around 2000 euros, > free of charges, per month. The position will be for one year with the > possibility > of a prolongation by another year; the starting date is flexible. > There are no teaching obligations, but researchers will have the opportunity to > interact > with students in the context of their projects. There is generous travel > support. > Applications should be sent in electronic form, including a CV, publication > list, motivation letter, and a copy or summary of the PhD thesis, to > bodirsky@hidemymail. > The review of applications begins immediately and continues until the position > is filled. > Informal inquires by email are welcome.

2013-01-14

GT Combi du LIX - lundi 14/1 à 14h (**) - Carsten Lange

Bonjour, Le prochain GT Combi du LIX aura lieu lundi 14 janvier 2013 à 14h (**) dans la salle Marcel-Paul Schützenberger (**). Carsten Lange (Équipe Combinatoire et Optimisation, UPMC) nous parlera de "Minkowski decompositions of associahedra into faces of a standard simplex". Le résumé est disponible ci-dessous. ** Notez bien l'heure et la salle inhabituelles ! ** Le programme du GT Combi du LIX est disponible sur le site web de l'équipe : http://www.lix.polytechnique.fr/combi/#seminaire À lundi, Marie et Vincent *************** Orateur : Carsten Lange (Équipe Combinatoire et Optimisation, UPMC) Titre : Minkowski decompositions of associahedra into faces of a standard simplex Résumé : J.-L. Loday gave a beautiful and simple combinatorial description for explicit realizations of associahedra. His construction was generalized subsequently and the resulting family of realizations is parametrized by Coxeter elements of the symmetric group. A remarkable property of these realizations is that they decompose into Minkowski sums and differences of dilated faces of a standard simplex. My talk consists of two parts. Firstly, I will explicitly describe the combinatorics of the realizaitions. Secondly, I will show that these polytopes in fact admit the mentioned Minkowski decomposition and I will give an efficient combinatorial algorithm to compute its coefficients. ***************

2013-01-11

GT Combi du LIX - lundi 7/1 à 11h - Laurent Menard

Bonjour, Tout d'abord, très bonne année 2013 à tous. Pour bien commencer cette nouvelle année, le prochain GT Combi du LIX aura lieu le lundi 7 janvier 2013 à 11h dans la salle Philippe Flajolet. Laurent Menard (Paris Ouest, Nanterre) nous parlera de "percolation sur la carte infinie uniforme". Le résumé est disponible ci-dessous. Le programme du GT Combi du LIX est disponible sur le site web de l'équipe : http://www.lix.polytechnique.fr/combi/#seminaire À lundi, Marie et Vincent *************** Orateur : Laurent Menard (Paris Ouest, Nanterre) Titre : Percolation sur la carte infinie uniforme Résumé : La carte infinie uniforme est la limite locale des cartes à n arêtes, sans contrainte de degré sur les faces, choisies uniformément au hasard. Nous montrerons comment un procédé d'épluchage, arête par arête, permet d'étudier la percolation sur cette carte. En particulier, cela permet d'obtenir les valeurs explicites du point critique pour la percolation par arêtes ainsi que la percolation par sites. Cet exposé est basé sur un travail en cours avec Pierre Nolin (ETH Zürich). ***************

2013-01-08

[Infolix] Fwd: Conference on Digital Enterprise : February 12-13 (Paris)

Pi�ce jointe: Conference DEDM2013 - Call For Participation2.pdf

2013-01-07

Talk by Prof. Chuck Liang

Chuck Liang (Prof, Hofstra University, NY, USA) will be visiting the Parsifal team the week of 17 Dec 2012. He will give the following talk in Salle Philippe Flajolet (2017) of LIX on Wednesday 19 December at 11h. -Dale Extending Intuitionistic Logic for Control From a relatively practical perspective, our goal is to achieve a computationally meaningful interpretation of disjunctive types, including the throwing and catching of exceptions, using a form of non-additive disjunction. Most of the work on extending the Curry-Howard isomorphism and lambda calculus are based on replacing intuitionistic logic with classical logic. In such a context "classical implication" is given the same computational interpretation as intuitionistic implication, i.e., as lambda abstraction. With this interpretation, the body of a lambda term, of *classical* type A->B, may not actually *compute* B in the sense that B is the result of introductions and eliminations. Instead, B may be the result of weakening. This loss of constructivity becomes especially acute in the presense of disjunction: a particular example is found in the classical equivalence between (A->B)vC and (A->C)vB. This equivalence is not consistent with the concept of localized scope that's expected in programs. Our solution to this problem is to introduce a *unified logic* in which classical and intuitionistic logics can co-exist without one subsuming the other. We introduce "Polarized Intuitionistic Control Logic" (PICL). This logic is a synthesis of our earliear works PIL and ICL. In particular, it contains as a natural fragment (ICL) that simply extends intuitionistic logic with an additional logic constant. This simplified fragment is already capable of encoding control operators such as call/cc while preserving intuitionistic implication. However, for a richer type system, we extend ICL with an additional class of formulas. We use polarity information encoded in the formulas to control the availability of certain structural rules, which allows us to unify classical and intuitionistic reasoning. We define a simple but useful Kripke semantics, a tableau/sequent calculus proof system and, most importantly, a natural deduction system with a term calculus. We also discuss the role of polarization in sequent calculus versus natural deduction systems. Part of this talk will consist of ongoing work and some non-finalized alternatives will also be discussed. !DSPAM:317,50c21f38285526109311275!

2012-12-17

Séminaire algorithmique du plateau de Saclay, le vendredi 14 Décembre.

Chers collègues, Le séminaire algorithmique du plateau de Saclay aura lieu le Vendredi 14 Décembre 2012 (14h30 -15h30) au LIX, Bâtiment Alan Turing 1 rue Honoré d'Estienne d'Orves, Campus de l'École Polytechnique, Palaiseau (Salle Gilles Kahn). Au programme: Orateur : Barnaby Martin, LIX, Palaiseau Title : Distance Constraint Satisfaction Problems Abstract : Infinite-domain Constraint Satisfaction Problems (CSPs) are by now a well-established research area. Perhaps surprisingly, it is only relatively recently that the structure of the integers has been considered for classes of template. While rationals model continuous time, integers model discrete time - though their additional structure typically introduces both complexity and complications. We will survey known results, especially for (Z;succ) as well as semilinear integer languages. Although less benign than the rationals, the integers maintain very basic structure, and we will consider the ways, model-theoretic and combinatorial, that this may be exploited in the search for complexity classifications. Pour plus de détails, voir http://www.lix.polytechnique.fr/~bodirsky/seminaire/, Merci de bien vouloir diffuser cette information le plus largement possible. Bien cordialement Johanne Cohen CR CNRS E-mail: Johanne.Cohen@hidemymail Phone: + 33 1 39 25 42 20 address: PRiSM,Université de Versailles 45, avenue des états-unis 78035 Versailles Cedex France

2012-12-14

talk at LIX

Speaker: Michael Bronstein University of Lugano, Switzerland / Intel Semiconductor Title: Nonrigid shape correspondence using sparsity Date: 11am on Friday, December 14th Location: Salle Philippe Flajolet (2ème étage), Bâtiment Alan Turing Abstract: In this talk, I will present a novel sparse modeling approach to non-rigid shape matching using only the ability to detect repeatable regions. As the input to our algorithm, we are given only two sets of regions in two shapes; no descriptors are provided so the correspondence between the regions is not know, nor we know how many regions correspond in the two shapes. I will show that even with such scarce information, it is possible to establish very accurate correspondence between the shapes by posing it as a problem of permuted sparse coding. In the second part of the talk, I will show how this approach can be extended to non-isometric shapes using coupled quasi-harmonic bases constructed using joint approximate diagonalization of Laplacian matrices. Bio: Michael Bronstein received the B.Sc. summa cum laude from the Department of Electrical Engineering in 2002 and Ph.D. with distinction from the Department of Computer Science, Technion, Israel, in 2007. In 2010, he has joined the Institute of Computational Science in the Faculty of Informatics at the University of Lugano (USI), Switzerland. Prior to joining USI, Michael held a visiting appointment at Stanford university. His main research interests are theoretical and computational methods in metric geometry and their application to problems in computer vision, pattern recognition, shape analysis, computer graphics, image processing, and machine learning. Michael Bronstein has authored over 70 publications in leading journals and conferences, over 20 patents, the research monograph Numerical geometry of non-rigid shapes (Springer, 2008) and edited two books. Highlights of his research were featured in CNN, SIAM News, and Wired. Michael Bronstein is the alumnus of the Technion Excellence Program and the Academy of Achievement. In 2012, he won the European Research Council (ERC) starting grant for research on computational similarity geometry. Besides academic work, Prof. Bronstein is actively involved in industrial applications and technology transfer and commercialization, and consulting to technological companies. His track record includes developing and licensing algorithms for large-scale video analysis applications at the Silicon Valley start-up company Novafora (2004-2009 as co-founder and VP of video technology) and developing coded-light 3D camera based on his patents at the Israeli start-up Invision (2009-2012 as one of the principal technologists). Following the acquisition of Invision by Intel in 2012, Michael Bronstein currently serves as advisor and research scientist at Intel.

2012-12-14

GT Combi du LIX - lundi 10/12 à 11h - Philippe Nadeau

Bonjour, Le prochain GT Combi du LIX aura lieu lundi 10 décembre 2012 à 11h dans la salle Philippe Flajolet. Philippe Nadeau (Institut Camille Jordan, Univ. Lyon I) nous parlera d' "éléments totalement commutatifs et chemins du plan". Le résumé est disponible ci-dessous. Le programme du GT Combi du LIX est disponible sur le site web de l'équipe : http://www.lix.polytechnique.fr/combi/#seminaire À lundi, Marie et Vincent *************** Orateur : Philippe Nadeau (Institut Camille Jordan, Univ. Lyon I) Titre : Eléments totalement commutatifs et chemins du plan Résumé : Un élément d'un groupe de Coxeter W est dit “totalement commutatif” si deux de ses décompositions réduites peuvent toujours être reliées par une suite de transpositions de générateurs adjacents et qui commutent. Ces éléments ont été étudiés en détail par Stembridge dans le cas où W est fini. Ils indexent une base d'un quotient de l'algèbre de Hecke de W, correspondant à l'algèbre de Temperly-Lieb dans le cas où W est de type A. Nous considérons ici W fini ou affine, et énumérons les éléments totalement commutatifs selon leur longueur de Coxeter. Notre approche consiste à encoder ces éléments par diverses classes de chemins du plan que nous décomposons récursivement pour obtenir les fonctions génératrices voulues. Pour le type A fini, cela redonne un théorème de Barcucci et al.; pour A affine, cela simplifie et précise des résultats de Hanusa et Jones. Pour tous les autres groupes finis et affines, nos résultats sont nouveaux. Cet exposé est basé sur un travail en collaboration avec Riccardo Biagioli et Frédéric Jouhet (Lyon). *************** !DSPAM:317,50bf9b6f231911319511417!

2012-12-10

[Infolix]Le LIX félicite le Docteur Chassignet.

Le LIX félicite le Docteur Chassignet pour sa thèse.

Modélisation et analyse automatisée de la radiographie de la main de l'enfant

lien vers le document

2012-12-06

Comete-Parsifal Seminar - Thu Dec 06, 10:30

Comete-Parsifal Seminar Thu Dec 06, 10:30 LIX - Bâtiment Alan Turing Salle 2017 - Philippe Flajolet http://www.lix.polytechnique.fr/comete/seminar/ Title: Quantitative Analysis for Multi-threaded Programs. Speaker: Tri Minh Ngo. Abstract: Quantitative theories of information flow gives us an approach to relax the absolute confidentiality properties that are difficult to satisfy for many practical applications. The classical information-theoretic approaches for sequential programs, where the program is modeled as a communication channel with only input and output, and the measure of leakage is based on the notions of initial and remaining uncertainty, are not suitable to multi-threaded programs. Reasoning about the exposed information flow of multi-threaded programs is more complicated, because the outcome of such programs depends on the scheduler policy, and the leakages in intermediate states also contribute to the overall leakage of the program. Besides, the information-theoretic approaches have been also shown to be counter-intuitive. This paper proposes a novel model of quantitative analysis for multi-threaded programs that also takes into account the effect of observables of intermediate states along the trace. We define the notion of the leakage of a program trace. Given the fact that the execution of a multi-threaded programs typically is described by a set of traces, the leakage of a program under a specific scheduler is computed as the expected value of the leakages of all possible traces. This model is also applicable to sequential programs. Examples are given to compare our approach with the existing approaches.

2012-12-06

[Infolix]Fwd: GT Combi du LIX - lundi 10/12 à 11h - Philippe Nadeau

Début du message réexpédié :

De : Vincent Pilaud <vincent.pilaud@lix.polytechnique.fr>
Objet : GT Combi du LIX - lundi 10/12 à 11h - Philippe Nadeau
Date : 5 décembre 2012 17:39:55 UTC+01:00
À : Vincent Pilaud <vincent.pilaud@lix.polytechnique.fr>
Cc: Marie Albenque <albenque@lix.polytechnique.fr>, Philippe Nadeau <nadeau@math.univ-lyon1.fr>

Bonjour,

Le prochain GT Combi du LIX aura lieu lundi 10 décembre 2012 à 11h dans la salle Philippe Flajolet. Philippe Nadeau (Institut Camille Jordan, Univ. Lyon I) nous parlera d' "éléments totalement commutatifs et chemins du plan". Le résumé est disponible ci-dessous.

Le programme du GT Combi du LIX est disponible sur le site web de l'équipe : http://www.lix.polytechnique.fr/combi/#seminaire

À lundi,
Marie et Vincent

***************

Orateur : Philippe Nadeau (Institut Camille Jordan, Univ. Lyon I)
Titre : Eléments totalement commutatifs et chemins du plan
Résumé :
Un élément d'un groupe de Coxeter W est dit “totalement commutatif” si deux de ses décompositions réduites peuvent toujours être reliées par une suite de transpositions de générateurs adjacents et qui commutent. Ces éléments ont été étudiés en détail par Stembridge dans le cas où W est fini. Ils indexent une base d'un quotient de l'algèbre de Hecke de W, correspondant à l'algèbre de Temperly-Lieb dans le cas où W est de type A. Nous considérons ici W fini ou affine, et énumérons les éléments totalement commutatifs selon leur longueur de Coxeter. Notre approche consiste à encoder ces éléments par diverses classes de chemins du plan que nous décomposons récursivement pour obtenir les fonctions génératrices voulues. Pour le type A fini, cela redonne un théorème de Barcucci et al.; pour A affine, cela simplifie et précise des résultats de Hanusa et Jones. Pour tous les autres groupes finis et affines, nos résultats sont nouveaux. Cet exposé est basé sur un travail en collaboration avec Riccardo Biagioli et Frédéric Jouhet (Lyon).

***************

!DSPAM:317,50bf9b6f231911319511417!

2012-12-05

GT Combi du LIX - lundi 3/12 à 11h - Robert Cori

Bonjour, Le prochain GT Combi du LIX aura lieu lundi 3 décembre 2012 à 11h dans la salle Philippe Flajolet. Robert Cori (LaBRI et LIX) nous parlera de "la notion de rang pour les configurations sur un graphe et un résultat qui rappelle la formule de Riemann-Roch". Le résumé est disponible ci-dessous. Le programme du GT Combi du LIX est disponible sur le site web de l'équipe : http://www.lix.polytechnique.fr/combi/#seminaire À lundi, Marie et Vincent *************** Orateur : Robert Cori (LaBRI et LIX) Titre : La notion de rang pour les configurations sur un graphe et un résultat qui rappelle la formule de Riemann-Roch Résumé : Plusieurs modèles de physique statistique consistent à considérer un graphe et des entiers associés aux sommets, une règle de transition entre les configurations est aussi définie. On examinera celle qui a été introduite pour le modèle du tas de sable mais avec des conditions légèrement différentes. Pour ce modèle, Baker et Norine ont défini une notion de rang, ceci les a amenés à prouver une formule qui présente de grandes similitudes avec celle de Riemann-Roch. Je présenterai une nouvelle preuve plus combinatoire de ce résultat et proposerai une étude du cas du graphe complet. Cela conduit à introduire des polynômes symétriques à deux variables qui peuvent être considérés comme des $q,t$-analogues des nombres de Catalan. Cet exposé présente des résultats d'un travail en commun avec Yvan Le Borgne. ***************

2012-12-03

Le LIX félicite le Docteur Chassignet.

Le LIX félicite le Docteur Chassignet pour sa thèse. Modélisation et analyse automatisée de la radiographie de la main de l'enfant le jeudi 29 novembre 2012 à 14h00 dans les locaux du LIX salle G. Kahn, bât. Turing à l'École Polytechnique Une version du manuscrit se trouve ici : http://www.lix.polytechnique.fr/Labo/Philippe.Chassignet/THESE/manuscrit.pdf Résumé : La forme et les dimensions des régions ossifiées de la main servent au diagnostic d'un certain nombre de pathologies de la croissance. Le problème pour une analyse automatique est de localiser et d'identifier les régions osseuses qui sont plus ou moins perceptibles sur la radiographie. Les juxtapositions et superpositions éventuelles induisent de nombreuses ambiguïtés de détection et d'identification. Nous introduisons un modèle morphologique qui est suffisamment souple pour traiter correctement les cas qui s'écartent sensiblement de la normalité. À titre de validation, nous avons analysé environ 800 images. La fiabilité des résultats permet d'envisager des applications diagnostiques directes, comme la détermination de l'âge osseux et l'analyse d'anomalies morphométriques. Les résultats peuvent aussi servir de base pour d'autres développements dans l'analyse des radiographies demandant, par exemple, un recalage précis ou une paramétrisation selon l'âge osseux. Abstract: The shape and size of ossified parts of children's hands are used in diagnosis of a number of growth pathologies. The problem in automatic analysis of hand radiographs is in locating and identifying visibly bony areas, not fully ossified in a child's hand, and whose juxtapositions and overlays introduce uncertainties in their detection and identification. This thesis introduces a morphological model, flexible enough to work in case of growth disorders, also where the visible bone shapes deviate significantly from normality. Applied to 800 radiographic images, the model was able to reliably identify a significant majority of pathological cases, with direct applications to diagnosis, e.g., bone age assessment, and analysis of morphometric abnormalities. Accurately identifying hand bones enable development of tools, assisting diagnosis of, e.g., growth, ossification rates, specifically requesting an image registration or specific parameter settings, according to the bone age. !DSPAM:317,50b7b31939521302114428!

2012-11-29

[Infolix]GT Combi du LIX - lundi 3/12 à 11h - Robert Cori

2012-11-28

GT Combi du LIX - lundi 26/11 à 11h - Nicolas Delfosse

Bonjour, Le prochain GT Combi du LIX aura lieu lundi 26 novembre 2012 à 11h dans la salle Philippe Flajolet. Nicolas Delfosse (LIX) nous parlera de "Percolation et codes correcteurs quantiques". Le résumé est disponible ci-dessous. Le programme du GT Combi du LIX est disponible sur le site web de l'équipe : http://www.lix.polytechnique.fr/combi/#seminaire À lundi, Marie et Vincent *************** Orateur : Nicolas Delfosse (LIX) Titre : Percolation et codes correcteurs quantiques Résumé : Les codes topologiques sont des codes correcteurs quantiques définis à partir de graphes plongés dans une surface. Ils ont été introduits par Kitaev, qui a proposé de construire un code quantique basé sur un pavage carré du tore. Nous commençons par rappeler comment les paramètres du code quantique s'expriment en fonction des propriétés du graphe. Nous observons ensuite la ressemblance entre effacements quantiques et phénomène de percolation. En utilisant cette ressemblance, nous obtenons une borne sur le seuil de percolation d'une famille de graphes hyperboliques, à partir de résultats de théorie de l'information quantique. Travail commun avec Gilles Zémor. ***************

2012-11-26

[Infolix] Fwd: [alp-diff] International Conference on DIGITAL ENTERPRISE DESIGN & MANAGEMENT(DED&M 2013) - 1rst CALL FOR PARTICIPATION: PROGRAM & REGISTRATION

---------------------------------------------------------------------------
International Conference on DIGITAL ENTERPRISE DESIGN & MANAGEMENT(DED&M
2013)

1rst CALL FOR PARTICIPATION: PROGRAM & REGISTRATION
---------------------------------------------------------------------------

February 12-13, 2013 - Jardins de l'Innovation d'Orange, Paris (France)

---------------------------------------------------------------------------
Web: http://www.dedm2013.dedm.fr – Email: contact@dedm.fr
Registration: http://www.dedm2013.dedm.fr/-Registration-.html
---------------------------------------------------------------------------

CONFERENCE OVERVIEW

The DED&M conference aims to be the meeting opened to all academic
researchers and professional practitioners who are interested in the
design and the governance of digital systems from an Enterprise
Architecture perspective. The event namely intends to put digital issues
at the heart of its program, but also to bring together all business and
technological stakeholders of the Digital Enterprises. This is why the
DED&M conference scope integrates both the digital customer & business
dimensions (new digital customers behaviors, digital strategies, digital
value chains, digital marketing, digital resources management and
governance, digital corporate partnerships, etc.) and the underlying
technological dimension (information & communication technology,
information systems architecture, database & software engineering, systems
and networks engineering, etc.).

- 150 participants & 10 keynote speakers from academic and professional
world leading organizations
- 12 contributed talks to discuss & share your vision on various topics
related to Digital Enterprise
- 2 open discussions with invited speakers and recognized outstanding
experts
- 1 conference dinner to gather speakers, partners & participants in a
prestigious Parisian place.

10 INTERNATIONAL SPEAKERS (here below are the first confirmed names)

New Digital Business Models

- Digital Communication Strategy - Sylvain Lafrance, HEC Montreal - Canada
- Digital Governance - Jean-René Lyon, Allianz - France
- Digital Ecosystems - Henri Verdier, Cap Digital – France

New Digital Practices & Technology

- Information Systems -Richard Baskerville, Georgia State University - USA
- Data Governance -François Bourdoncle, Exalead -Dassault Systèmes -France
- Ecosystem Management - Dominique Cuppens, RFF - France
- Complexity Management - Bertrand Kientz, Amadeus – France

ONLINE REGISTRATION

You can already register to the conference and benefit from a reduction
until December 15, 2012.
For more information:
http://www.dedm2013.dedm.fr/Electronic-Registration.html.

PARTNERS & SPONSORS

CESAMES, Ecole Polytechnique, Digiteo, Supélec, ENSTA ParisTech, MEGA
International, Ecole Centrale de Paris, Telecom ParisTech, Bouygues
Télécom, Dassault Aviation, Thales, DCNS, DGA, Innovation and Regulation
Orange Chair, BNP Paribas, Institut Carnot Mines, Systematic,
CEISAR, BIZZdesign, Orange, AIM and le CNAM.

2012-11-23

[Infolix]Fwd: Séminaire algorithmique du plateau de Saclay, le vendredi 16 Novembre 2012

Chers collègues,

Le séminaire algorithmique du plateau de Saclay aura lieu le
Vendredi 16 novembre 2012 (14h30 -15h30) au LIX salle Grace-Hopper,
bâtiment Alan Turing.

Au programme:

Titre :   Linear programming and the complexity of finite-valued CSPs

Exposant : Johan Thapper

Résumé : I will present a complete complexity classification for the
finite-valued constraint satisfaction problem (VCSP). The VCSP can be seen
as minimisation of separable functions, that is, the objective function is
given as a sum of bounded-arity functions. Our result gives a dichotomy
between problems satisfying a submodularity-like condition which are
solvable in polynomial time by a linear programming relaxation, and NP-hard
problems. The result generalises a host of partial classifications spanning
the last 15 years.
This is joint work with Standa Zivny (Warwick, UK).

Bien cordialement
Johanne Cohen

CR CNRS
E-mail:    Johanne.Cohen@prism.uvsq.fr
Phone:    + 33 1 39 25 42 20
address: PRiSM,Université de Versailles
              45, avenue des états-unis
              78035 Versailles Cedex
      France

2012-11-23

[Infolix]GT Combi du LIX - lundi 26/11 à 11h - Nicolas Delfosse

2012-11-23

[hipercom] J. Yi at 2012 IEEE International Conference on Wireless Information Technology and Systems

He is presenting paper "Smart Route Request for On-demand Route Discovery in Constrained Environments", joint work with T. Clausen and A. Bas. And, it is in Hawaii!!
+ More

2012-11-23

[Infolix] [LABOLIX] Comete-Parsifal Seminar - Thu Dec 06, 10:30

Comete-Parsifal Seminar

Thu Dec 06, 10:30
LIX - Bâtiment Alan Turing
Salle 2017 - Philippe Flajolet
http://www.lix.polytechnique.fr/comete/seminar/

Title: Quantitative Analysis for Multi-threaded Programs.
Speaker: Tri Minh Ngo.
Abstract:
Quantitative theories of information flow gives us an approach to relax the absolute confidentiality properties that are difficult to satisfy for many practical applications. The classical information-theoretic approaches for sequential programs, where the program is modeled as a communication channel with only input and output, and the measure of leakage is based on the notions of initial and remaining uncertainty, are not suitable to multi-threaded programs. Reasoning about the exposed information flow of multi-threaded programs is more complicated, because the outcome of such programs depends on the scheduler policy, and the leakages in intermediate states also contribute to the overall leakage of the program. Besides, the information-theoretic approaches have been also shown to be counter-intuitive.

This paper proposes a novel model of quantitative analysis for multi-threaded programs that also takes into account the effect of observables of intermediate states along the trace. We define the notion of the leakage of a program trace. Given the fact that the execution of a multi-threaded programs typically is described by a set of traces, the leakage of a program under a specific scheduler is computed as the expected value of the leakages of all possible traces. This model is also applicable to sequential programs. Examples are given to compare our approach with the existing approaches.

2012-11-22

[Infolix]Soutenance de thèse de R. Lebreton, 11/12/2012

Début du message réexpédié :

De : Romain Lebreton <lebreton@lix.polytechnique.fr>

Objet : [LABOLIX] Soutenance de thèse de R. Lebreton, 11/12/2012

Date : 22 novembre 2012 10:49:07 UTC+01:00

À : labolix@lix.polytechnique.fr

Bonjour,

j'ai le plaisir de vous inviter à ma soutenance de thèse, intitulée

Contributions à l’algorithmique détendue et
à la résolution des systèmes polynomiaux.

La soutenance aura lieu

le mardi 11 décembre 2012 à 13h30
à l'École polytechnique, amphithéâtre Gay-Lussac.

Et pour se remettre de ces émotions, un pot ouvert à tous suivra. Si vous savez que vous serez présent, un petit mail de votre part ne pourra que faciliter l'organisation du pot.

La soutenance se déroulera devant le jury composé de

- Richard Brent (Australian National University, Rapporteur)
- Marc Giusti (CNRS & École polytechnique, Directeur)
- Bernard Mourrain (Inria Sophia Antipolis - Méditerranée, Rapporteur)
- Jean-Michel Muller (École Normale Supérieure de Lyon, Examinateur)
- Éric Schost (University of Western Ontario, Directeur)
- Annick Valibouze (Université Paris 6, Examinateur)
- Kazuhiro Yokoyama (University of Rikkyo, Rapporteur)
- Paul Zimmermann (Inria Nancy - Grand Est, Examinateur)

Vous pouvez consulter mon manuscrit (en version non définitive) sur ma page personnelle :
http://www.lix.polytechnique.fr/~lebreton/fichiers/Thesis.pdf

Résumé :
========

Cette thèse est en majeure partie dédiée au calcul rapide de remontée p-adique par des algorithmes détendus.
Dans une première partie, nous présentons le cadre général des algorithmes détendus et de leur application au calcul de p-adiques récursifs. Pour appliquer ce cadre à la remontée p-adique de divers systèmes d'équations, il reste à transformer ces équations implicites en équations récursives. Ainsi, la seconde partie traite des systèmes d'équations linéaires, éventuellement différentiels. La remontée de résolutions de systèmes polynomiaux se trouve en troisième partie. Dans tous les cas, les nouveaux algorithmes détendus sont comparés, en théorie comme en pratique, aux algorithmes existants.
En quatrième partie, nous étudions l'algèbre de décomposition universelle d'un polynôme. Nous développons un algorithme rapide pour calculer une représentation adéquate de cette algèbre et l'utilisons pour manipuler efficacement les éléments de l'algèbre.
Finalement, nous montrons en annexe que la recherche d'invariants fondamentaux d'algèbres d'invariants sous un groupe fini peut se faire directement modulo p, facilitant ainsi leur calcul.

Abstract:
=========

This PhD thesis is mostly devoted to the computation of p-adic lifting by relaxed algorithms.
In a first part, we introduce relaxed algorithms and their application to the computation of recursive p-adics. In order to use this framework for the p-adic lifting of various systems of equations, we have to transform the given implicit equations into recursive equations. The case of systems of linear equations, possibly differential, is treated in the second part. This third part contains the lifting of resolutions of polynomial systems. In any cases, these new relaxed algorithms are compared, both in theory and practice, to existing algorithms.
In the fourth part, we focus on the universal decomposition algebra. We present a fast algorithm which computes an adequate representation of this algebra and use it to compute efficiently with the elements of this algebra.
Finally, we show in the appendix that finding fundamental invariants of polynomial invariants algebras under a finite group can be done directly modulo p, hence making their computation easier.

Pour venir à l'École polytechnique:
http://www.polytechnique.edu/accueil/vie-sur-le-campus/acceder-au-campus/

Arriving on campus:
http://www.polytechnique.edu/home/life-on-campus/arriving-on-campus/

Je vous prie de m'excuser pour les doublons.
Bien cordialement,

Romain Lebreton.

2012-11-22

[Infolix] Comete-Parsifal Seminar - Thu Dec 06, 10:30

Comete-Parsifal Seminar

Thu Dec 06, 10:30
LIX - Bâtiment Alan Turing
Salle 2017 - Philippe Flajolet
http://www.lix.polytechnique.fr/comete/seminar/

2012-11-21

[hipercom] IETF '83 in Paris: a slew of new specifications from us....

The IETF '83 is in Paris, from March 25-30, 2012. In preparation for this meeting, a set of new specifications have been prepared:

draft-clausen-lln-rpl-experiences-01 has emerged, analyzing and detailing operational considerations from RPL.

draft-ietf-manet-olsrv2-14 has been published. This is, we hope, the final version of OLSRv2, ready to be Working-Group Last Called.

draft-ietf-manet-packetbb-sec-09 has been published; this specification was just approved by the IESG, and is now sitting comfortably in the RFC Editor's queue.

draft-ietf-manet-nhdp-sec-01, the logical next-step using packetbb-sec for securing NHDP (RFC6130) has, then, been published, in order to match packetbb-sec closely, clear up odds and ends and (hopefully) soon be ready for WGLC also.

To that end, draft-herberg-manet-nhdp-sec-threats-01 has been published. This draft presents in some details the security threats that the draft above is intended to address.

Finally, draft-clausen-lln-loadng-02 has been published. This specification presents what we believe to be an applicable routing protocol for LLNs. Compared to -01, this document is more explicit on a number of things, not the least of which is the use of metrics, but there are numerous updates and improvements.
+ More

2012-11-21

[hipercom] J. A. Cordero at the 31st Annual IEEE International Conference on Computer Communications (INFOCOM 2012) in Orlando, Florida (United States)

He is presenting the paper "Impact of Jitter-based Techniques on Flooding over Wireless Ad hoc Networks: Model and Analysis", joint work with Philippe Jacquet and Emmanuel Baccelli.
+ More

2012-11-21

[Infolix]Fwd: GT Combi du LIX - lundi 19/11 à 11h - Basile Morcrette

Début du message réexpédié :

De : Vincent Pilaud <vincent.pilaud@lix.polytechnique.fr>
Objet : GT Combi du LIX - lundi 19/11 à 11h - Basile Morcrette
Date : 14 novembre 2012 14:23:54 UTC+01:00
À : Vincent Pilaud <vincent.pilaud@lix.polytechnique.fr>
Cc: Marie Albenque <albenque@lix.polytechnique.fr>, Basile Morcrette <Basile.Morcrette@lip6.fr>

Bonjour,

Le prochain GT Combi du LIX aura lieu lundi 19 novembre 2012 à 11h dans la salle Philippe Flajolet. Basile Morcrette (Inria Rocquencourt et LIP6, UPMC) nous parlera d'"Urnes de Polya algébriques". Le résumé est disponible ci-dessous.

Le programme du GT Combi du LIX est disponible sur le site web de l'équipe : http://www.lix.polytechnique.fr/combi/#seminaire

À lundi,
Marie et Vincent

***************

Orateur : Basile Morcrette (Inria Rocquencourt et LIP6, UPMC)
Titre : Urnes de Polya algébriques
Résumé :
La suite des tirages dans une urne de Polya équilibrée additive peut se voir comme une marche dans le quart de plan, où les pas sont pondérés. Dans le cas classique des marches dans le quart de plan, la question de la nature de la série génératrice a été traitée récemment par Bousquet-Mélou et Mishna, Bostan et Kauers, Fayolle et Raschel. Nous nous posons ici le même problème dans le cadre des urnes de Polya équilibrées: quelles séries génératrices sont algébriques?
Par une approche automatique de Guess'n'Prove, nous exhibons un ensemble de cas où la série est algébrique. Cela nous amène à une classification partielle de ces urnes. Nous obtenons ensuite des preuves élémentaires d'algébricité. Enfin, une étude analytique (utilisant analyse de singularité et méthode de cols coalescents) permet de conclure sur les lois limites de ces urnes.

***************

2012-11-14

[Infolix] Fwd: New Conference on Digital Enterprise, February 2013, Paris - Program & Registration

Pi�ce jointe: Conference DEDM2013 - Call For Participation.pdf

2012-11-13

[Infolix] Fwd: [LABOLIX] announcement: workshop on proof theory

Début du message réexpédié :

De : Stefan Hetzl <hetzl@lix.polytechnique.fr>
Objet : [LABOLIX] announcement: workshop on proof theory
Date : 12 novembre 2012 14:31:39 UTC+01:00
À : labolix@lix.polytechnique.fr

Dear LIX-members,

On Thursday and Friday this week, the Parsifal-team organizes a
workshop entitled

Collegium Logicum 2012: Structural Proof Theory

at LIX. Please see the website at

http://team.inria.fr/parsifal/meetings/cl2012/

for more detailed information such as the list of talks and the schedule.

You are all welcome to attend!

Best regards,

Stefan Hetzl

2012-11-12

[Infolix] [LABOLIX] Comete-Parsifal Seminar Thu June 07, 15:00

Comete-Parsifal Seminar Thu June 07, 15:00 LIX, Ecole Polytechnique Salle de Reunion, LIX http://www.lix.polytechnique.fr/comete/seminar/ Lien pour accéder au campus : http://www.polytechnique.edu/accueil/vie-sur-le-campus/acceder-au-campus/ Link to reach the campus: http://www.polytechnique.edu/home/life-on-campus/arriving-on-campus/ Title: Interaction solos Speaker: Andrei Dorman Abstract: We build a language of processes corresponding exactly to the most general Interaction Nets in which cells "are" solos. We then introduce several styles of subcalculi we call designs, out of which, a rather unusual one and show it is as expressive as the whole system: names are shared by at most two processes. In other words, channels only connects two processes (a bit like a physical wire can only connect two machines). Conversely, translating such a system into the other designs, when possible, introduces divergence. This first results leads us to a possible classification of complexity of non-determinism. Titre: Solos d'interaction Speaker: Andrei Dorman Résumé: On construit un langage de processus qui correspond exactement aux réseaux d'interactions, où chaque cellule "est" un solo. On introduit ensuite différents styles de sous-calculs qu'on nomme designs, dont un assez inhabituel dans la théorie des processus et l'on montre qu'il est aussi expressif que le calcul complet: les canaux ne relient que deux processus au maximum (autrement dit, un nom n'est partagé qu'au plus par deux processus), à l'image des câbles physiques qui ne peuvent relier que deux machines. Inversement, traduire un tel système dans les autres designs, quand c'est possible, introduit nécessairement de la divergence. Ce premier résultat nous met sur la piste d'une classification de complexité du non-déterminisme.

2012-07-24

[Infolix] [LABOLIX] Reminder: Comete-Parsifal Seminar Thu June 21, 15:00

Comete-Parsifal Seminar Thu Jun 21, 15:00 LIX, Ecole Polytechnique Salle de Reunion, LIX http://www.lix.polytechnique.fr/comete/seminar/ Lien pour accéder au campus : http://www.polytechnique.edu/accueil/vie-sur-le-campus/acceder-au-campus/ Link to reach the campus: http://www.polytechnique.edu/home/life-on-campus/arriving-on-campus/ Title: Measuring Information Leakage using Generalized Gain Functions. Speaker: Kostas Chatzikokolakis. Abstract: This talk introduces g-leakage, a rich generalization of the min-entropy model of quantitative information flow. In g-leakage, the benefit that an adversary derives from a certain guess about a secret is specified using a gain function g. Gain functions allow a wide variety of operational scenarios to be modeled, including those where the adversary benefits from guessing a value close to the secret, guessing a part of the secret, guessing a property of the secret, or guessing the secret within some number of tries. I will discuss important properties of g-leakage, including bounds between min-capacity, g-capacity, and Shannon capacity. Moreover I will discuss a connection between a strong leakage ordering on two channels, C1 and C2, and the possibility of factoring C1 into C_2C_3, for some C3. Based on this connection, I will propose a generalization of the Lattice of Information from deterministic to probabilistic channels

2012-07-24

[Infolix] Fwd: [alp-diff] PROGRAM & REGISTRATION CSD&M 2012 - CALL FOR PARTICIPATION

Début du message réexpédié :

De : roda@lix.polytechnique.fr
Objet : [alp-diff] PROGRAM & REGISTRATION CSD&M 2012 - CALL FOR PARTICIPATION
Date : 24 juillet 2012 12:59:21 HAEC
À : alp-diffusion@univ-lille1.fr
Répondre à : roda@lix.polytechnique.fr

------------------------------------------------------------------------
Third International Conference on Complex Systems Design and Management
(CSD&M 2012) - 1st CALL FOR PARTICIPATION: PROGRAM & REGISTRATION
------------------------------------------------------------------------

Decembre 12-14, 2012 - Cite Internationale Universitaire de Paris(France)

------------------------------------------------------------------------
Web: http://www.csdm2012.csdm.fr – Email: contact@csdm.fr
Registration info: http://www.csdm2012.csdm.fr/-Registration-.html
------------------------------------------------------------------------

-* Conference Overview

The CSD&M conference is the annual meeting point for both industrial &
academic actors working on all dimensions of design and management of
complex industrial systems. It addresses societal & industrial challenges
and covers the main industrial areas dealing with complex systems and
technical & scientific methods used to model and master these types of
systems.

- 280 participants & 17 keynote speakers from academic and industrial
world leading organizations
- 20 contributed talks and 1 poster session to discuss & share your vision
on topics related to complex systems
- 2 open discussions and tutorials with invited speakers and recognized
outstanding experts
- 1 software and engineering tool session to share the latest
technological news
- 1 conference dinner to gather speakers, partners & participants for a
unique moment in the prestigious Musée d’Orsay

-* 17 International Speakers

Societal Challenges: Risk & Safety
- Economical risk: Pierre-Noël Giraud, professor, Ecole des Mines de Paris
- France
- Financial risk: Raphaël Douady, founder, RiskData - France
- Energetical risk: Pierre Bornard, vice-president, RTE - France
- Insurance risk: Bernard Laporte, head of R&D and Training, AXA – France

Industrial Challenges: Risk & Safety
- Nuclear risk: Akira Yamaguchi, professor, Osaka University - Japan
- City risk: Olivier Flous, Technical Director of Transport & Safety,
Thales Communications & Security S.A. - France
- Risk and control: Jean-Christophe Visier, head of the sustainable
development department, CSTB - France
- Certification approach for future aviation systems: Pascal Medal, head
of Certification Experts Dpt- EASA – Germany

Scientific State of the Art
- Systems theory: Wolter Fabrycky, professor, Viriginia Tech. – USA
- Systems Modelling: Manfred Broy, professor, Technische Universität
Munchen - Germany
- Complexity and Safety: Anas Alfaris, head of the Center for Complex
Engineering Systems (CCES), Riyadh – Saudi Arabia
- Systems simulation: Yves Caseau, executive vice president «
Technologies, Services & Innovation », Bouygues Telecom – France

Methodological State of the Art
- Systems engineering: David Walden, chairman, Sysnovation & INCOSE - USA
- Architecting complex systems in new domains and problem: Patrick
Godfrey, professor, University of Bristol - UK
- Reliability of electricity networks: Pierre-Etienne Labeau, professor,
Ecole Polytechnique de Bruxelles - Belgium
- EEC Systems Vision: Khalil Rouhana, director of the directorate –
General for Communications Networks, Content & Technology Components &
Systems - European Commission

-* Online Registration

Benefit an important reduction on your participation fee by registering
before August 31, 2012 (550€ instead of 700€ for academics, 700€ instead
of 950€ for industrials). For more information:
http://www.csdm2012.csdm.fr/Electronic-Registration.html.

-* Our Partners & Sponsors

CESAMES, Ecole Polytechnique, Digiteo, Supélec, ENSTA ParisTech, MEGA
International, Ecole Centrale de Paris, Telecom ParisTech, Bouygues
Télécom, CEA, IBM Rational Software, Dassault Aviation, Thales, DCNS,
Knowledge Inside, DGA, EDF, Esterel Technologies, INCOSE, AFIS, Chaire OSD
de l'Ecole Polytechnique, EADS, Chaire Orange de Télécom ParisTech,
Institut de la Maîtrise des risques, Atego et MathWorks

2012-07-24

[Infolix] Fwd: Conference Digital Enterprise Design & Management, Paris: Call for Paper

Pi�ce jointe: DEDM 2013 - Call for Papers.pdf

2012-07-24

[Infolix] Fwd: Conference Digital Enterprise Design & Management, Paris: Call for Papers #2

Pi�ce jointe: DED&M 2013 - Call for Papers.pdf

2012-07-24

[Infolix] Reminder: Comete-Parsifal Seminar Thu Jul 12, 15:00

Comete-Parsifal Seminar Thu Jul 12, 15:00 LIX, Ecole Polytechnique Salle de Reunion, LIX http://www.lix.polytechnique.fr/comete/seminar/ Lien pour accéder au campus : http://www.polytechnique.edu/accueil/vie-sur-le-campus/acceder-au-campus/ Link to reach the campus: http://www.polytechnique.edu/home/life-on-campus/arriving-on-campus/ Title: Verification of distributed probabilistic systems under partial information. Speaker: Sergio Giro. Abstract: In the verification of systems that involve probabilities, it is crucial to study qualitative properties concerning the probability of certain events as, for instance, 'the probability that a failure occurs is less that 0.01'. In case the system under consideration is distributed, each of the components of the system might have a partial view of the information available to other components. The analysis of these systems is carried out by considering 'distributed adversaries' with restricted observations. In this talk I will summarise six years of research on automatic verification of distributed probabilistic systems. On the negative side, we proved the verification problem to be undecidable in general and NP-complete for some restricted systems. Nevertheless, we also introduced some techniques for overestimation of worst-case probabilities, and showed that the concept of distributed adversaries can be used to improve existing techniques such as partial order reduction.

2012-07-24

[Infolix] Fwd: Conference Digital Enterprise Design & Management, Paris: Call for Papers #2

Pi�ce jointe: DED&M 2013 - Call for Papers.pdf

2012-07-11

[Infolix] rappel : Conference combinatoire et informatique

Je me permets de vous rappeler l'après-midi d'exposés à l'interface entre mathématiques discrètes et informatique théorique qui est organisée aujourd'hui : "Journée Combinatoire et Informatique 2012" le 4 Juillet 2012 Ecole Polytechnique Salle de conférence du Centre de Mathématiques Laurent Schwartz. 14h - 14h45 : Noga Alon (Tel Aviv University) "Graphs, integers and communication" 15h - 15h45 : Prasad Tetali (Georgia Tech) "A tight Cheeger-type inequality for higher eigenvalues of Laplacians of graphs" 15h45 - 16h15 : pause café 16h15 -17h : Jacob Fox (MIT) "Chromatic number, clique subdivisions, and the conjectures of Hajos and Erdos-Fajtlowicz" Bien cordialement, Bernadette Charron-Bost

2012-07-09

[Infolix] talk announcement

Comete-Parsifal Seminar

Thu Jul 12, 15:00
                LIX, Ecole Polytechnique
            Salle de Reunion, LIX
        http://www.lix.polytechnique.fr/comete/seminar/

Lien pour accéder au campus :
http://www.polytechnique.edu/accueil/vie-sur-le-campus/acceder-au-campus/
Link to reach the campus:
http://www.polytechnique.edu/home/life-on-campus/arriving-on-campus/

Title: Verification of distributed probabilistic systems under partial
information.
Speaker: Sergio Giro.
Abstract:
In the verification of systems that involve probabilities, it is
crucial to study qualitative properties concerning the probability of
certain events as, for instance, 'the probability that a failure
occurs is less that 0.01'. In case the system under consideration is
distributed, each of the components of the system might have a partial
view of the information available to other components. The analysis of
these systems is carried out by considering 'distributed adversaries'
with restricted observations. In this talk I will summarise six years
of research on automatic verification of distributed probabilistic
systems. On the negative side, we proved the verification problem to
be undecidable in general and NP-complete for some restricted systems.
Nevertheless, we also introduced some techniques for overestimation of
worst-case probabilities, and showed that the concept of distributed
adversaries can be used to improve existing techniques such as partial
order reduction.

-------------------------------------------------------------------------------------------

Catuscia Palamidessi

INRIA-Saclay and LIX Office: +33 (0)1 69 33 41 17

École Polytechnique Fax: +33 (0)1 69 33 40 49

Rue de Saclay Email: catuscia@lix.polytechnique.fr

91128 Palaiseau, FR URL: www.lix.polytechnique.fr/~catuscia

-------------------------------------------------------------------------------------------

2012-07-04

[Infolix] Fwd: [LABOLIX] Comete-Parsifal Seminar Thu June 21, 15:00

Début du message réexpédié :

De : "Andrés A. Aristizábal P." <andresaristi@lix.polytechnique.fr>
Objet : [LABOLIX] Comete-Parsifal Seminar Thu June 21, 15:00
Date : 12 juin 2012 15:38:19 HAEC
À : kostas@chatzi.org, catuscia@lix.polytechnique.fr, comete@lix.polytechnique.fr, parsifal@lix.polytechnique.fr, labolix@lix.polytechnique.fr

Comete-Parsifal Seminar

    Thu Jun 21, 15:00
                LIX, Ecole Polytechnique
           Salle de Reunion, LIX
        http://www.lix.polytechnique.fr/comete/seminar/

Lien pour accéder au campus :
http://www.polytechnique.edu/accueil/vie-sur-le-campus/acceder-au-campus/
Link to reach the campus:
http://www.polytechnique.edu/home/life-on-campus/arriving-on-campus/

Title: Measuring Information Leakage using Generalized Gain Functions.
Speaker: Kostas Chatzikokolakis.
Abstract:
This talk introduces g-leakage, a rich generalization of the
min-entropy model of quantitative information flow. In g-leakage, the
benefit that an adversary derives from a certain guess about a secret
is specified using a gain function g. Gain functions allow a wide
variety of operational scenarios to be modeled, including those where
the adversary benefits from guessing a value close to the secret,
guessing a part of the secret, guessing a property of the secret, or
guessing the secret within some number of tries. I will discuss
important properties of g-leakage, including bounds between
min-capacity, g-capacity, and Shannon capacity. Moreover I will
discuss a connection between a strong leakage ordering on two
channels, C1 and C2, and the possibility of factoring C1 into C_2C_3,
for some C3. Based on this connection, I will propose a generalization
of the Lattice of Information from deterministic to probabilistic
channels

2012-06-19

[Infolix] Fwd: Conference Digital Enterprise Design & Management, Paris: Call for Paper

Pièce jointe: DEDM 2013 - Call for Papers.pdf

2012-06-12

[Infolix]Fwd: 17th IEEE International Conference on the Engineering of Complex Computer Systems – Paris, July 2012.

Pi�ce jointe: ICECCS 2012 - call for participation.pdf

2012-06-12

[Infolix] Fwd: gt combinatoire du LIX: lundi 4 juin, 11h

Chers amis Le prochain gt combinatoire du lix aura lieu ce lundi 4 juin mars à 11h dans la salle de séminaire du laboratoire: nous aurons le plaisir d'écouter Eric Fusy qui parlera de dessin de graphes. Désolé pour l'annonce un peu tardive... Amicalement, Gilles Schaeffer titre: *Dessin périodique de triangulations sur le cylindre et sur le tore* resume: Nous étendons l'algorithme incrémental de dessin de De Fraysseix, Pollack et Pach (initialement pour triangulations planaires) au cas des triangulations cylindriques. La grille du dessin obtenu (grille x-périodique) est de la forme Z/wZ \times [0..h] avec w\leq 2n et h \leq n(2d+1), n étant le nombre de sommets et de la distance (distance de graphe) entre les deux bords. Dans un second temps, et par une réduction simple au cas du cylindre (utilisant la notion de tambourin) nous montrons comment dessiner toute triangulation torique sur une grille (x-périodique et y-périodique) de la forme Z/wZ\times Z/hZ avec w\leq 2n et h\leq n(2c-1)+1, n étant le nombre de sommets et c la longueur d'un plus court cycle non contractible. Comme c\leq (2n)^{1/2}, l'aire de la grille obtenue est O(n^{5/2}). Travail en commun avec Luca Castelli Aleardi et Olivier Devillers

2012-06-08

[Infolix] Fwd: [LABOLIX] Reminder: Comete-Parsifal Seminar Thu May 10, 15:00

Comete-Parsifal Seminar

Thu May 10, 15:00
                LIX, Ecole Polytechnique
           Salle de Reunion, LIX
        http://www.lix.polytechnique.fr/comete/seminar/

Lien pour accéder au campus :
http://www.polytechnique.edu/accueil/vie-sur-le-campus/acceder-au-campus/
Link to reach the campus:
http://www.polytechnique.edu/home/life-on-campus/arriving-on-campus/

Title: Probabilistic modal mu-calculus with independent product
Speaker: Matteo Mio.
Abstract:
The modal µ-calculus (Lµ) is the logic obtained by extending standard
propositional modal logic with least and greatest fixed points
operators. This logic was intensively studied in the last 20 years, as it
allows the expression of many interesting properties of labeled transition
systems.
The probabilistic modal µ-calculus (pLµ) is a generalization of Lµ,
designed for expressing properties of probabilistic labeled transition
systems. In this talk I will discuss an extension of pLµ, called
probabilistic
modal µ-calculus with independent product, which can express more
complex properties of practical interest. We provide two semantics for
this extended logic: one denotational and one based on a new kind of games
which we call Tree games. The main result is the equivalence of the two
semantics. The proof is carried out in ZFC set theory extended with
Martin’s Axiom at the first uncountable cardinal.

--
Andrés A. Aristizábal P.
PhD Student
École Polytechnique
Ingeniero de Sistemas y Computación
Pontificia Universidad Javeriana Cali
Especialista en Periodismo
Universidad de los Andes Bogotá

2012-05-29

[Infolix] Fwd: [LABOLIX] Reminder: Comete-Parsifal Seminar Thu May 10, 15:00

Thu May 10, 15:00
                LIX, Ecole Polytechnique
           Salle de Reunion, LIX
        http://www.lix.polytechnique.fr/comete/seminar/

Lien pour accéder au campus :
http://www.polytechnique.edu/accueil/vie-sur-le-campus/acceder-au-campus/
Link to reach the campus:
http://www.polytechnique.edu/home/life-on-campus/arriving-on-campus/

Title: Probabilistic modal mu-calculus with independent product
Speaker: Matteo Mio.
Abstract:
The modal µ-calculus (Lµ) is the logic obtained by extending standard
propositional modal logic with least and greatest fixed points
operators. This logic was intensively studied in the last 20 years, as it
allows the expression of many interesting properties of labeled transition
systems.
The probabilistic modal µ-calculus (pLµ) is a generalization of Lµ,
designed for expressing properties of probabilistic labeled transition
systems. In this talk I will discuss an extension of pLµ, called
probabilistic
modal µ-calculus with independent product, which can express more
complex properties of practical interest. We provide two semantics for
this extended logic: one denotational and one based on a new kind of games
which we call Tree games. The main result is the equivalence of the two
semantics. The proof is carried out in ZFC set theory extended with
Martin’s Axiom at the first uncountable cardinal.

--
Andrés A. Aristizábal P.
PhD Student
École Polytechnique
Ingeniero de Sistemas y Computación
Pontificia Universidad Javeriana Cali
Especialista en Periodismo
Universidad de los Andes Bogotá

2012-05-29

[Infolix] Fwd: Call For Papers #3: 3rd International Conference on Complex Systems Design & Management - Dec. 2012, Paris

Pièce jointe: 3rd_Conf._Complex_Systems_Design__Management_2012_-_Call_for_Papers 3.pdf

2012-05-29

[Infolix] Fwd: gt combinatoire du LIX: lundi 12 mars, 11h, Xavier Goaoc

Chers amis
Le prochain gt combinatoire du lix aura lieu ce lundi 12 mars à 11h (au lieu
de 14h habituellement) dans la
salle de séminaire du laboratoire: nous aurons le plaisir d'ecouter
Xavier Goaoc (LORIA, INRIA) sur les nombres de Helly:

Titre : Autour des nombres de Helly

Résumé : Dans cet exposé, je relierai le théorème de Helly sur l'intersection d'ensembles convexes (1913) à diverses questions récentes de nature algorithmique, combinatoire et topologique. L'exposé sera destinés aux non-spécialistes et ne supposera aucune de ces notions connues.
Issu d'un travail commun avec Éric Colin de Verdière (CNRS-ENS) et Grégory Ginot (UPMC-ENS).

2012-05-29

[Infolix] Fwd: gt combinatoire du LIX: vendredi 23 mars, 11h, Christian Stump

Bonjour,

Le prochain gt combinatoire du lix aura lieu ce vendredi 23 mars à 11h en salle de réunion du préfa du LIX. Christian Stump nous présentera une bijection explicite entre les k-triangulations et les k-uplets de chemins de Dyck sans croisement.

À vendredi,
Vincent

**************

Date : Vendredi 23 mars à 11h
Orateur : Christian Stump
Titre : A bijection between k-triangulations and k-fans of Dyck paths
Résumé : I will present a bijection between k-triangulations of the n-gon and k-fans of Dyck paths. This bijection goes through maximal north-east fillings of triangles, pipe dreams, flagged tableaux, and plane partitions. This is joint work with Luis Serrano.

2012-05-29

[Infolix]Fwd: [LABOLIX] Séminaire Robert Giegerich - Mercredi 16 Mai à 14h

Bonjour à tous,

Robert Giegerich, professeur à l'université technique de Bielefeld et invité DGAR de l'équipe AMIB pendant le mois de Mai, fera un exposé demain Mercredi 16 Mai à 14h en salle de séminaire du LIX. Ses thématiques de recherche sont très larges (allant de la compilation à la bioinformatique des ARN), avec un intérêt prononcé pour la programmation dynamique (algébrique) au sens large, et ses exposés toujours très agréables (peut être aurez vous le plaisir d'assister à une de ses chorégraphies destinées à comprendre le repliement des ARN...).
Vous y êtes donc les bienvenus, même si la bioinformatique n'est pas centrale à vos recherches.

Amicalement,

Yann

-------------------------------------------------------------------------------------------------------------------------------

Titre : Enjoy Dynamic Programming in Bellman's GAP
Orateur: Robert Giegerich

Applications of the dynamic programming paradigm are ubiquitous computer science, and especially so in bioinformatics. The discipline of algebraic dynamic programming liberates programmers from cumbersome coding and debugging, as algorithms can be described on a declarative level of abstraction. Teaching DP algorithms becomes more rewarding, as crucial ideas are better exhibited in a more abstract representation. The algebraic discipline underlies a good number of bioinformatics tools, such as RNAshapes, RNAlishapes, RNAhybrid, PknotsRG, KnotInFrame, Locomotif, and pKiss, some which are used widely.
Quite in contrast to this success, the proliferation of algebraic dynamic programming as a method remains marginal. It has been hindered by the fact that its original implementation was based on a Haskell-derived syntax and provided only marginal compiler optimizations.
The recent Bellman's GAP programming system provides a declarative language GAP-L with a Java-style syntax, designed to create dynamic programming algorithms over sequence data in algebraic style. The Bellman's GAP compiler generates code which is competitive to hand-coded DP recurrences, and arguably more reliable. It provides numerous features that would require considerable skills and effort in hand-coding, such as k-best analysis, full or stochastic backtracing, classified dynamic programming and algebra products, code generation for parallel hardware, and analysis of asymptotic space and runtime efficiency, including the consideration of space-time tradeoffs. Several
bioinformatics tools have been re-implemented in Bellman's GAP by a mere change of syntax, with a considerable gain in efficiency.
If you have been a hard-coding dynamic programmer, try Bellman's GAP. It may bring joy into your life.

Bellman's GAP is joint work with Georg Sauthoff.

--

2012-05-29

[Infolix] Fwd: [LABOLIX] Comete-Parsifal Seminar Thu May 10, 15:00

Comete-Parsifal Seminar

Tue Jan 17, 14:30
                LIX, Ecole Polytechnique
           Salle de Reunion, LIX
        http://www.lix.polytechnique.fr/comete/seminar/

Lien pour accéder au campus :
http://www.polytechnique.edu/accueil/vie-sur-le-campus/acceder-au-campus/
Link to reach the campus:
http://www.polytechnique.edu/home/life-on-campus/arriving-on-campus/

Title: Probabilistic modal mu-calculus with independent product
Speaker: Matteo Mio.
Abstract:
The modal µ-calculus (Lµ) is the logic obtained by extending standard
propositional modal logic with least and greatest fixed points
operators. This logic was intensively studied in the last 20 years, as
it allows the expression of many interesting properties of labeled
transition systems.
The probabilistic modal µ-calculus (pLµ) is a generalization of Lµ,
designed for expressing properties of probabilistic labeled transition
systems. In this talk I will discuss an extension of pLµ, called
probabilistic
modal µ-calculus with independent product, which can express more
complex properties of practical interest. We provide two semantics for
this extended logic: one denotational and one based on a new kind of
games which we call Tree games. The main result is the equivalence of
the two semantics. The proof is carried out in ZFC set theory extended
with Martin’s Axiom at the first uncountable cardinal.

--
Andrés A. Aristizábal P.
PhD Student
École Polytechnique
Ingeniero de Sistemas y Computación
Pontificia Universidad Javeriana Cali
Especialista en Periodismo
Universidad de los Andes Bogotá

2012-05-02

[Infolix] [gdr-im] LIX-Qualcomm fellowship 2012

Cher(e)s collègues, avec mes excuses pour les copies multiples... -b (English version follows) LIX, le Laboratoire d'Informatique de l'Ecole polytechnique, sollicite des candidatures pour la 2011-2012 LIX-Qualcomm Postdoctoral Fellowship pour la recherche en informatique. http://www.lix.polytechnique.fr/fellowship LIX offre un environnement de recherche unique, réunissant des chercheurs permanents du CNRS, INRIA et le CEA, ainsi que les professeurs de l'Ecole polytechnique. Nous encourageons un mélange de théorique, appliquée, et la recherche expérimentale. LIX abrite environ 120 chercheurs, y compris les visiteurs universitaires, postdocs et doctorants, organisés en 11 équipes de recherche sur les sujets suivants: * Data and Web Mining * Wireless and Ad Hoc Networking * Computer Graphics, Vision and Visual Computing * Bioinformatics * Algorithms, Optimization * Formal Languages for Mobile and Distributed Systems * Reliability and Safety of Software * Complex Systems * Combinatorics * Algebraic Modelization * Cryptology and Coding Theory * Automatic Proof Processing * Algorithms for Distributed Systems * Operations Research * Algorithmic Game Theory * Models for Continuous Time Computations * Complexity * Constraint Satisfaction Problems Plus d'informations sur les équipes de recherche au LIX peut être trouvé à http://www.lix.polytechnique.fr/ La bourse postdoctorale LIX-Qualcomm offre aux jeunes scientifiques d'une qualité exceptionnelle occasion de faire progresser leur carrière universitaire en tant que chercheurs dans une de nos 11 équipes de recherche. Le boursier est libre de poursuivre ses propres recherches, mais devrait permettre d'identifier et d'intégrer une équipe de recherche à LIX dans son domaine d'intérêt. Les candidats sont *fortement* encouragés à solliciter des contacts avec le personnel de recherche dans leur équipe(s) de recherche à l'avance. La bourse sera d'un an, avec possibilité de candidater pour un renouvellement d'une année supplémentaire. La bourse est soutenue par une allocation concurrentielle. Les candidats doivent avoir obtenu un doctorat *après* janvier 2011, ou devraient s'attendre à recevoir une bourse *avant* le début de l'automne 2012. Candidatures seront acceptées jusqu'au mercredi 16/5/2012, et doivent être soumises en ligne. De plus amples détails sur cette bourse, et la procédure de candidature, peut être trouvé à http://www.lix.polytechnique.fr/fellowship = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = LIX, the Laboratory for Computer Science at the Ecole Polytechnique, France, is inviting applications for its 2012-2013 LIX-Qualcomm Postdoctoral Fellowship for research in computer science. http://www.lix.polytechnique.fr/fellowship LIX offers a unique academic research environment, bringing together permanent staff researchers from CNRS, INRIA, and CEA, as well as resident faculty from Ecole Polytechnique. We encourage a mixture of theoretical, applied, and experimental research. Including academic visitors, postdoctoral fellows and PhD students, LIX is home to about 120 researchers, organized in 11 research teams on the following subjects: * Data and Web Mining * Wireless and Ad Hoc Networking * Computer Graphics, Vision and Visual Computing * Bioinformatics * Algorithms, Optimization * Formal Languages for Mobile and Distributed Systems * Reliability and Safety of Software * Complex Systems * Combinatorics * Algebraic Modelization * Cryptology and Coding Theory * Automatic Proof Processing * Algorithms for Distributed Systems * Operations Research * Algorithmic Game Theory * Models for Continuous Time Computations * Complexity * Constraint Satisfaction Problems Further information about the research teams at LIX can be found at http://www.lix.polytechnique.fr/ The LIX-Qualcomm postdoctoral fellowship provides young scientists of outstanding quality an opportunity to advance their academic career as resident research fellows in one of these 11 research teams. The fellow is free to continue his/her own research, however expected to identify and integrate with a LIX research team in his/her area of interest. Applicants are strongly encouraged to solicit contact with staff researchers in their team(s) of research in advance. The fellowship will be for one year, with an opportunity for a fellow to present candidature for renewal for one additional year. The fellowship is supported by a competitive stipend. Applicants must have received a PhD degree *after* January 2011 or should expect to receive one *before* the fellowship commences in fall 2012. Applications will be accepted until Wednesday May 16, 2012, and must be submitted on-line. Further details on the fellowship, and the application procedure, can be found at http://www.lix.polytechnique.fr/fellowship

2012-04-25

[hipercom] Friday 23: Computer Networking Seminar, Fred Baker (Cisco): "Changing the World"

The Department of Computer Science (DIX) and the Laboratory of Computer Science (LIX) is pleased to invite you to a seminar on Friday the 23rd of March at 13:30 in amphi Becquerel:

"Changing the World"

Fred Baker, Cisco fellow, will discuss the impact of technology on business,
finance and lifestyle.

Fred Baker is one of the "Grand Old Ones" in computer networking and the Internet: he started his career developing computer networking technology in 1978 while with CDC - and has not ceased pushing communications technology forward ever since. Since 1994, he has been with Cisco Systems, where he is currently holding the rank of "Fellow" -the top distinction bestowed upon engineering ranks, and currently held by only 15 individuals among the ~70000 employees at Cisco.

Fred Baker's career is rich with considerable contributions, of both technical, political and societal in nature.

His technical contributions include having authored 50 RFCs (Internet Standards Documents), on topics ranging from routing protocols through QoS to network management. This includes many of the protocols that make the Internet of today able to work. His latest RFC was published in 2011 (on IPv6-to-IPv6 Network Prefix Translation).

Fred Baker has served as Chair of Internet Engineering Task Force (IETF) from 1996-2001, managing the Internet Standards development process. He has served on the Internet Architecture Board (IAB), chaired several working groups in the IETF - as well as served, and serves, on advisory committees to several universities world-wide, NGOs, and government commissions, such as the US Federal Communications Commission (FCC) and the National Institute of Standards and Technology (NIST) Smart Grid Interoperability Panel.

Fred Baker is passionate about technology, and its impact on society. When inviting him to come give a talk at Ecole Polytechnique, the request was that he talk about something he was passionate about. His response was simply: "I like changing the world - can I come talk about how I use technology to change the world?"….

This is a rare occasion for Polytechnique students and faculty to get face-to-face with an exceptional engineer and leader, whose work has been, and continues to be, instrumental in making the Internet what it is today. Moreover, an engineer who has made it his successful mission of bringing technology to the service of society.
+ More

2012-03-21

[Infolix] Fwd: Call For Papers #3: 3rd International Conference on Complex Systems Design & Management - Dec. 2012, Paris

Pi�ce jointe: 3rd_Conf._Complex_Systems_Design__Management_2012_-_Call_for_Papers 3.pdf

2012-03-20

[Infolix]Fwd: [LABOLIX] Séminaire Crypto Mercredi 7 mars

Bonjour à tous,

mercredi 7 mars deux exposés auront lieu dans la salle de conférence du LIX.

------
À 13h30: Pierre-Alain FOUQUE (ENS Paris)

TITRE: On some algebraic and statistical results on multivariate problems

RÉSUMÉ: Multivariate cryptography is a branch of public-key cryptography where the public key is usually composed of a system of quadratic forms. For encryption and signature schemes, the quadratic system is a public easy-to-invert quadratic system F which is hidden using two randomly chosen linear bijections S and T which correspond to the secret key. The public-key system is the composition of the three mappings and has the following form ToFoS. To decrypt a given ciphertext, the adversary has to solve a quadratic system which is a NP-hard problem. In this talk, we will be interesting in the decomposition problem which consists in recovering the secret mappings S and T given the public key. In cryptographic instances, the public key system is not random-looking and for some schemes such as SFLASH, we will show that it is easy to recover the trapdoor using algebraic properties of the quadratic forms F in polynomial time. The more general problem where the system F is not easy-to-invert but random, is more difficult. In this case, we will show new exponential-time algorithms that improve on the previous results using the birthday paradox.

This talk is based on a joint work with Charles Bouillaguet and Gilles Macario-Rat for the first part and with Charles Bouillaguet and Amandine Weber for the second part.
-----

À 14h45: Julia PIELTANT (Institut de Mathématiques de Luminy, Marseille)

TITRE : Complexité bilinéaire de la multiplication dans les extensions finies de F_q

RÉSUMÉ : La multiplication dans les corps finis est un problème central en cryptographie et en théorie des codes : l’efficacité de la multiplication influe sur la rapidité du chiffrement et du déchiffrement mais aussi sur celle des différentes méthodes de décodage. C’est pourquoi, dans les 30 dernières années, un intérêt considérable a été porté au problème de la détermination de sa complexité, c’est-à-dire du nombre d’opérations élémentaires dans F_q nécessaires pour calculer le produit de deux éléments de F_{q^n}.
On distingue en fait deux types d’opérations élémentaires : les opérations scalaires (additions, multiplications par des constantes) comptabilisées par la complexité scalaire et les opérations bilinéaires (multiplications de deux éléments de F_q dépendants directement des éléments de F_{q^n} dont on effectue le produit) comptabilisées par la complexité bilinéaire. Ce dernier type de complexité est indépendant de la base de F_{q^n} sur F_q choisie et est de plus relié au problème de la détermination du rang de tenseur.
Au cours de cet exposé, on se propose de présenter l'algorithme de type Chudnovsky, qui est actuellement le meilleur algorithme de multiplication connu en terme de complexité bilinéaire, ainsi qu'un panorama de ses récentes améliorations et des bornes de complexité bilinéaire qu'il permet d'obtenir.
-----

--
Alain Couvreur
INRIA Saclay Île-de-France
Laboratoire LIX - École Polytechnique
91128 Palaiseau Cedex

+33 1 69 33 44 06
perso: http://www.lix.polytechnique.fr/~alain.couvreur/

2012-03-20

[Infolix]Fwd: [LABOLIX] séminaire JF Puget : 29 mars, 10h, salle de conf

Début du message réexpédié :

De : David Savourey <savourey@lix.polytechnique.fr>
Objet : [LABOLIX] séminaire JF Puget : 29 mars, 10h, salle de conf
Date : 12 mars 2012 13:27:56 HNEC
À : labolix@lix.polytechnique.fr

Bonjour à tous,
Jean-François Puget (IBM, Ilog) donnera un séminaire le jeudi 29 mars 2012 à 10h, dans la salle de conf du lix.

Voici un résumé in English :
Advanced Topic in Mathematical Optimization Software : Dealing With Symmetry
Symmetry in a combinatorial problem could appear as a good property as it
reduces the search of candidate solutions to representatives of symmetry
equivalence classes. While this is a good theoretical property, making it
work in practice in an optimization software can be tricky. We will explain
why symmetry is bad for current software, how symmetry can be efficiently
recognized, and how symmetry can be used to prune the search for solutions.
We'll use IBM ILOG CPLEX applied to Mixed Integer Programming problems as
an example.

Venez nombreux!
David

2012-03-19

[Infolix] Fwd: gt combinatoire du LIX: vendredi 23 mars, 11h, Christian Stump

Début du message réexpédié :

De : Vincent Pilaud <vincent.pilaud@ens.fr>
Objet : gt combinatoire du LIX: vendredi 23 mars, 11h, Christian Stump
Date : 18 mars 2012 20:19:40 HNEC
À : Vincent Pilaud <vincent.pilaud@ens.fr>
Cc : Christian Stump <christian.stump@gmail.com>

Bonjour,

Le prochain gt combinatoire du lix aura lieu ce vendredi 23 mars à 11h en salle de réunion du préfa du LIX. Christian Stump nous présentera une bijection explicite entre les k-triangulations et les k-uplets de chemins de Dyck sans croisement.

À vendredi,
Vincent

**************

Date : Vendredi 23 mars à 11h
Orateur : Christian Stump
Titre : A bijection between k-triangulations and k-fans of Dyck paths
Résumé : I will present a bijection between k-triangulations of the n-gon and k-fans of Dyck paths. This bijection goes through maximal north-east fillings of triangles, pipe dreams, flagged tableaux, and plane partitions. This is joint work with Luis Serrano.

2012-03-18

[Infolix] gt combinatoire du LIX: lundi 12 mars, 11h, Xavier Goaoc

2012-03-12

[Infolix] PostDoc available at LIX, Ecole Polytechnique, France

The following postdoc position is available at the LIX labs on the campus of Ecole Polytechnique, France.

PostDoc: Designing and implementing proof certificates

Context

ProofCert is a recently awarded ERC Advanced Grant that will be funded for the five years 2012-2016. The goal of ProofCert is to design a format for proof certificates that can capture the proof evidence within all major theorem provers while also being checkable by a simple, declarative proof checker. This format must allow treating some inference steps as (non-deterministic) computation and as well as supporting (bounded) proof reconstruction.

A postdoctoral position is available within the ProofCert project. This position is concerned with helping to design, implement, and experimentally validate the design of proof certificates for a range of theorem provers in classical first-order logic. The position is for one year, with a second year extension possible. It should start in Fall 2012.

The ideal candidate should have strong backgrounds in

basic proof theory (in particular, the sequent calculus);
various automated and interactive theorem proving systems; and
programming in logic programming (Prolog or lambda Prolog) as well as other high-level programming languages (such as ML or Haskell).

Venue

The postdoc will be a member of the INRIA Parsifal team and will work in a new building on the campus of the Ecole Polytechnique that houses the Laboratoire d’Informatique (LIX). This campus is situated to the south of Paris, an easy commute from Paris on the RER B regional train line. French proficiency is not necessary.

Application

Candidates must have a Ph.D.; if the Ph.D. thesis is not yet defended when the application is made, the candidate should provide the planned defense date and the composition of the thesis committee.

To apply, contact Dale Miller (dale.miller at inria.fr) and include a cover letter and (links to) your CV and publication list. Additional material, such as letters of recommendation, will be requested if necessary. Early expression of interest is encouraged. We plan to make a decision on this position around the beginning of April 2012.

More Information

Further information regarding ProofCert and the Parsifal team can be found at the following links.
- The ERC Advanced Grant ProofCert: http://team.inria.fr/parsifal/proofcert/
- The INRIA Parsifal team: http://team.inria.fr/parsifal/

- Positions offered by Parsifal in 2012: http://team.inria.fr/parsifal/positions/
- Miller's web page: http://www.lix.polytechnique.fr/Labo/Dale.Miller/

2012-03-02

[Crypto] News: February

Morgan Barbier's thesis, new publications, and visits from Peter Beelen and Christophe Petit.

2012-03-02

[Infolix] Full Professor Position of Computer Science at Ecole Polytechnique & LIX

Ecole Polytechnique is hiring a full professor of computer science.

The applicants should be scientists recognized at the highest
international level. They will join the computer science laboratory
at Ecole Polytechnique (LIX)

The applicants are also expected to show a high motivation for
teaching computer science at Ecole Polytechnique, and to present
innovative teaching projects and pedagogical skills.

Professors of Ecole Polytechnique salaries follow the grid for
"Professeurs de classe exceptionnelle" which is the highest rank in
French academia.

Support for helping the installation for the applicant as well as
her/his team are negociable.

For any further information, potential candidates can turn to Benjamin
Werner, head of the CS department and Olivier Bournez, director of the
laboratory.

(Benjamin.Werner@polytechnique.fr,
Olivier.Bournez@lix.polytechnique.fr)

Applications should be submitted by *** 30 March 2012 *** to the
following web site
http://de.polytechnique.fr/candidatures/OffreView.cfm?ID=243&Language=EN

Secretary: Catherine Bensoussan (+33 1 69 33 40 33) catherine.bensoussan@polytechnique.edu

2012-02-29

[Infolix] Fwd: gt combi du lix, lundi 14h, Nicolas Bonichon

Début du message réexpédié :

Objet : gt combi du lix, lundi 14h, Nicolas Bonichon

Date : 6 janvier 2012 00:56:30 HNEC

Chers amis,

Pour la première scéance 2012 du gt combinatoire du lix
nous accueillerons ce lundi a 14h Nicolas Bonichon du LaBRI.

Titre : Spanner géométrique planaire de degré au plus 6.
Résumé : We consider the problem of constructing planar spanners of
Euclidean graphs with the smallest maximum degree. We present a 6-spanner
of degree bound by 6. The best previous bound on the degree of planar
spanner was 14 with a stretch of $\approx 3.53$. The spanner we proposed
can be easily computed the Triangular Distance Delaunay triangulation
introduced by Chew in 1989, that is known to have a stretch factor of 2 but
its degree may not be bounded. (Travail réalisé en collaboration avec Cyril
Gavoille, Nicolas Hanusse et Ljubomir Perković.)

Amitiés,
Gilles

2012-01-31

[Infolix] gt combi du lix, vendredi janvier 11h, Jarek Rossignac

Chers collegues, nous avons les plaisir d´accueillir au IX le prof. Jarek Rossignac, qui donnera un exposé demain (vendredi 20) a´ 11h (salle des séminaires du LIX). Vous trouverez le titre et résumé ci-dessous. A bientot Luca Castelli Aleardi --- Mesh parsimony: Towards compact formats for processing and transmitting triangulations Jarek Rossignac School of Interactive Computing, Georgia Institute of Technology http://www.gvu.gatech.edu/~jarek/ Modern representations of 3D shapes in Engineering, Scientific, Medical, and Entertainment domains are based on triangulations. The constant increase in the fidelity—and hence complexity—of these models increases storage cost and hence adversely impacts transmission and processing performance. To address this problem, we discuss compact formats for transmitting and processing triangulations. On the practical side, we review the Corner-Table (CT)—a representation for triangle meshes, where the connectivity is encoded as 13 rpv (references per vertex)—and the associated standard sets of random, mesh-traversal corner-operators. Its simplicity and compactness makes it a prime choice for teaching and implementing mesh-processing algorithms. We also discuss its VOT extension to tetrahedral meshes, which requires storing about 48 rpv, and the associated mesh-traversal wedge-operators. Then, we review the popular triangle-mesh compression, Edgebreaker, which requires about 2 bpv (bits per vertex) and can be implemented with a few lines of code, and discuss some improvements and extensions to tetrahedral meshes, including TetStreamer, which requires only about 10 bpv. Finally, we discuss recent advances in compact mesh-representations that support the corner-operators and wedge-operators at constant cost. These include SOT (which halves the storage requirements of CT and VOT), SQuad for triangle meshes (which requires 4 rpv), and LR (which orders the vertices around a nearly Hamiltonian cycle and requires only about 1.6 rpv). On the theoretical side, we cast the recent approaches as special cases of the catalogue approach of Castelli-Aleardi&Devillers, investigate the role of re-orderings and the interplay between compression, streaming, and random-access support, and seek to extract the essential information that is captured in the connectivity of a triangle mesh. The talk is based on joint work with U. Bischoff, T. Gurung, P. Lindstrom, M. Luffel, and A. Szymczak and other colleagues.

2012-01-31

[hipercom] Smart Object Security workshop announcement: March 23 at Ecole Polytechnique

Hipercom@LIX is proud to participate in the organization of the Smart Object Security workshop, March 23, 2012 - held at Ecole Polytechnique.

This workshop is a highly interactive and dynamic event - explicitly not a "mini conference", but a place for technical discussion and exchange of ideas.

Consult the URL, submit a position paper and consider participating ;)
+ More

2012-01-29

[Infolix] [DMANET] 3rd INTERNATIONAL CONFERENCE ON COMPLEX SYSTEMS DESIGN & MANAGEMENT

--------------------------------------------------------------------------- 3rd INTERNATIONAL CONFERENCE ON COMPLEX SYSTEMS DESIGN & MANAGEMENT (CSD&M 2012) December 12-14, 2012 – Cité Internationale Universitaire, Paris (France) ------------------------------------------------------------------------ Website: http://www.csdm2012.csdm.fr/ Call for Papers section: http://www.csdm2012.csdm.fr/-Submission-.html Contact: contact@csdm.fr ------------------------------------------------------------------------ CALL FOR PAPERS # 1 The management of large-scale complex industrial systems has a considerable strategic importance for an important number of enterprises (most notably in Europe and North America). This spawned the relatively new academic field of "system architecture & engineering", producing a body of research that allows engineers to manage the increasing complexity of the technical systems they design. By its very nature, this field is at the interface between industry and academia, and requires its practitioners to be well versed in industrial application-related as well as theoretical knowledge. The ambition of the CSDM conference is to be the meeting point for the industrial and academic environments working in the design and management of complex industrial systems. IMPORTANT DATES • Optional abstract pre-submission deadline : April 6, 2012 • Submission deadline : April 20, 2012 • Acceptance notice for industrial contribution: June 15, 2012 • Acceptance notice for academic contribution: June 29, 2012 • Final version submission deadline: August 31, 2012 • Conference: December 12-14, 2012 • "Best papers" awards: December 14, 2012 SUBMISSION PROCEDURE AND BEST PAPERS AWARDS As the CSDM conference is both industrial and academic, there will be two different submission procedures according to the type of submitted contributions : industrial submissions and scientific submissions. Selected papers will be presented by their authors either on the format of a 30 minutes talk or as a poster during a special session. The program committee is pleased to inform you of the following awards for the best CSDM 2011 papers in 2 categories : 1 prize of 2.000€ for the best academic or industrial paper and 1 prize of 1.000€ for the best student paper. For more details, see http://www.csdm2012.csdm.fr/-Submission-.html. CONFERENCE TOPICS •Industrial domains: Transport constructors & operators, Defense & security, Electronics & robotics, Energy & environment, Health & welfare services, Media & communications, Software & e-services. •Scientific and technical topics: Systems fundamentals, Systems modelling, Systems architecture, Systems engineering, Industrial projects, Systems metrics, Systems quality, Systemic tools. •Systems types: Embedded systems, Transportation systems, Software systems, Information systems, Systems of systems, Artificial eco-systems. MORE DETAILS More information can be found on the conference website: http://www.csdm2012.csdm.fr. For any question, please write an email to: contact@csdm.fr. ********************************************************** * * Contributions to be spread via DMANET are submitted to * * DMANET@zpr.uni-koeln.de * * Replies to a message carried on DMANET should NOT be * addressed to DMANET but to the original sender. The * original sender, however, is invited to prepare an * update of the replies received and to communicate it * via DMANET. * * DISCRETE MATHEMATICS AND ALGORITHMS NETWORK (DMANET) * http://www.zaik.uni-koeln.de/AFS/publications/dmanet/ * **********************************************************

2012-01-27

[Infolix] [LABOLIX] Reminder: Comete-Parsifal Seminar Tue Jan 17, 14:30

Comete-Parsifal Seminar Tue Jan 17, 14:30 LIX, Ecole Polytechnique, Aile 0 Salle de Reunion, LIX http://www.lix.polytechnique.fr/comete/seminar/ Lien pour accéder au campus : http://www.polytechnique.edu/accueil/vie-sur-le-campus/acceder-au-campus/ Link to reach the campus: http://www.polytechnique.edu/home/life-on-campus/arriving-on-campus/ Title: Checking NFA equivalence with bisimulations up to congruence. Speaker: Filippo Bonchi. Abstract: We introduce bisimulation up to congruence as a technique for proving language equivalence of non-deterministic finite automata. Exploiting this technique we devise an optimization of the classical algorithm by Hopcroft and Karp that, instead of computing the whole determinized automata, explores only a small portion of it. Although the optimized algorithm remains exponential in worst case (the problem is PSPACE-complete), experimental results show improvements of several orders of magnitude over the standard algorithm. Joint work with Damien Pous.

2012-01-27

[Infolix] Fwd: [LABOLIX] Comete-Parsifal Seminar Tue Jan 17, 14:30

2012-01-27

[Infolix] gt combi du lix, lundi 16 janvier 14h, Omid Amini

Chers amis, Ce lundi a 14h nous accueillerons au gt combinatoire du lix Omid Amini de l'ENS. Titre: Théorème de Riemann-Roch tropical Résumé: Je présente un survol des résultats récents autour du théorème de Riemann-Roch en géométrie tropicale. Le prochain exposé aura exceptionnellement lieu vendredi 20 janvier (au lieu du lundi), l'orateur sera Jarek Rossignac (Georgia Tech). Amitiés, Gilles

2012-01-27

[Infolix] [LABOLIX] Comete-Parsifal Seminar Mon Sep 19, 14:30

Comete-Parsifal Seminar Mon Sep 19, 14:30 LIX, Ecole Polytechnique Salle de Reunion 'Prefa', LIX http://www.lix.polytechnique.fr/comete/seminar/ Title: Keeping track of your friends and enemies: privacy threats of new mobile technologies. Speaker: Myrto Arapinis. Abstract: Joint work with Loretta Mancini, Eike Ritter, and Mark Ryan. The proliferation of portable computing devices, such as mobile phones, Bluetooth devices, and RFID tags, has lead to a range of new computer security problems. In order to fulfil their goals, these devices need to report our movements to service providers such as mobile phone network operators, banks, and governments. While most of users accept that the service providers can track their physical movements, few would be happy if an arbitrary third party could do so. Such a possibility would enable all kinds of undesirable behaviours, ranging from criminal stalking to more mundane monitoring of spouse or employee movements. For this reason, protocols have been designed to prevent third parties from identifying wireless messages as coming from a particular user. These protocols usually include cryptography and make use of temporary identifiers, in an effort to achieve the aim of untraceability by third parties. At CSF'10, we presented a formal framework for analysing untraceability/unlinkability in the applied pi calculus. We used our framework to show that French e-Passports are traceable, while British ones aren't. In this talk, I will present you our work on the analysis of Universal Mobile Telecommunication System (UMTS) protocols. I will show you a problem we have identified with the UMTS authentication and key establishment protocol: although mobile phones use temporary identities to identify themselves to the Network, a replayed message can be used to identify a particular mobile phone. Our attack exploits the fact that the victim's phone will reply with subtly different error messages, depending on whether the replayed request is associated with it or with a different phone. To thwart this attack, we propose a modification of the protocol, and verify the proposed fix using our framework and the ProVe

2012-01-10

[Infolix] Offre d'emploi dans le projet MaGiX / Job offer in MaGiX project

(english version below) ---------------------------------------------------------------- Annonce ---------------------------------------------------------------- Dans le contexte du projet MaGiX http://magix.lix.polytechnique.fr un emploi d'ingenieur en developpement est ouvert : http://magix.lix.polytechnique.fr/profil3.fr.html Ingénieur spécialiste en formats de documents scientifiques Date limite pour postuler (voir site web) : 30 Septembre 2011 ---------------------------------------------------------------- Announcement ---------------------------------------------------------------- In the context of the MaGiX project http://magix.lix.polytechnique.fr we are proposing a position for one software engeneer : http://magix.lix.polytechnique.fr/profil3.en.html Specialist in scientific document formats The deadline for applications is september 30, 2011 (see

2012-01-10

[Infolix]Fwd: [gt-geocal] Troisième annonce: Journées communes LAC-GEOCAL. 24 et 25 novembre

Début du message réexpédié :

De : Lutz Strassburger <lutz@lix.polytechnique.fr>
Objet : [gt-geocal] Troisième annonce: Journées communes LAC-GEOCAL. 24 et 25 novembre
Date : 12 octobre 2011 11:05:17 HAEC
À : Lutz Strassburger <lutz@lix.polytechnique.fr>, lengrand@lix.polytechnique.fr

Bonjour à tous,

Les groupes de travail GEOCAL (Géométrie du calcul) et LAC (Logique,
Algèbre et Calcul) du GDR Informatique mathématique organisent une
rencontre commune les

Jeudi 24 et Vendredi 25 Novembre 2011

à l'Ecole Polytechnique, Palaiseau.

GEOCAL: http://iml.univ-mrs.fr/~regnier/gdr-im/
LAC: http://www.pps.jussieu.fr/~kesner/gdr/lac.html

Vous devriez dès à présent réserver ces journées.

Vous pouver trouver le site de la rencontre à l'adresse

http://www.lix.polytechnique.fr/~lengrand/Events/LACGeoCal/

notamment avec la possibilité de s'y inscrire en ligne.

La clôture des inscriptions avec proposition d'exposé est fixée au 1er
Novembre 2011, et celle des inscriptions sans proposition d'exposé est fixée au 15 Novembre.

L'inscription est gratuite et vous permet de participer gratuitement aux
repas organisés.

N'hésitez pas à nous contacter si vous avez besoin d'informations
supplémentaires.

En espérant vous voir nombreux,

Bien cordialement,

Stéphane Lengrand & Lutz Strassburger,
organisateurs, LIX

--Apple-Mail=_6B7569D8-C971-4B03-8192-E819

2012-01-10

[Infolix] Fwd: Call For Papers: 3rd International Conference on Complex Systems Design & Management - Dec. 2012, Paris

Pi�ce jointe: 3rd Conf. Complex Systems Design & Management 2012 - Call for Papers.pdf

2012-01-06

[hipercom] 82th IETF in Taipei, Taiwan, Nov. 13-18 2011

We're off for another IETF, this time in Taipei, Taiwan, with lots of new things to show for.

OLSRv2 has been updated (YAY!), a couple of MANET-related MIB-documents and OLSRv2-related security documents have emerged also.

PACKETBB-SEC has closed WGLC, and we are hoping to see that it be sent to the IESG soon and, hopefully, emerge as RFC soon.

Additionally, in the Low-Power Lossy Networking (LLN) / AMI space, two documents have appeared: "The LLN On-demand Ad hoc Distance-vector Routing Protocol - Next Generation" (draft-clausen-lln-loadng) specifies an efficient LLN routing protocol. The accompanying document "Experience with the LOADng routing protocol for LLNs" (draft-lavenu-lln-loadng-interop) documents an interoperability test of 3 independent implementations hereof.

All this, and much more, is on the agenda for the 82th IETF - where we will be represented by Axel Colin de Verdiere, Jiazi Yi, Thomas Clausen and Emmanuel Baccelli.
+ More

2011-11-24

[hipercom] T. Clausen at The Eighth ACM International Symposium on Performance Evaluation of Wireless Ad Hoc, Sensor, and Ubiquitous Networks

He is presenting the paper "A Comparative Performance Study of the Routing Protocols LOAD and RPL with Bi-Directional Traffic in Low-power and Lossy Networks (LLN)", joint work with Ulrich Herberg.
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2011-11-24

[hipercom] J. Yi at the 7th International Conference on Network and Service Management

CNSM 2011, held from Oct 24 to Oct 28 2011, in the beautiful city that we are more or less familiar with -- Paris. He is presenting the paper "Performance Analysis of SNMP in OLSRv2-Routed MANETs", joint work with U. Herberg and Robert Cole.
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2011-11-05

[hipercom] J. YI at IEEE iThings/CPSCom 2011 in Dalian, China

He is presenting the paper "Vulnerability Analysis of the Simple Multicast Forwarding (SMF) Protocol for Mobile Ad Hoc Networks" in the 4th IEEE International Conference on Cyber, Physical and Social Networking. Joint work with T. Clausen and U. Herberg.
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2011-11-01

[hipercom] T. Clausen at the 9th IEEE/IFIP International Conference on Embedded and Ubiquitous Computing (IEEE EUC 2011) in Melbourne, Australia

He is presenting the paper "Delay Tolerant Networking with OLSRv2", joint work with Ulrich Herberg.
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2011-11-01

[hipercom] J. YI at The 14th International Symposium on Wireless Personal Multimedia Communications

In Brest, France, with the paper "Multipath Routing Protocol for MANET: Application to H.264/SVC Video Content Delivery", joint work with Benoit Parrein (Universite de Nantes), Dan Radu (Technical University of Cluj-Napoca, Romania).
+ More

2011-10-24

[tanc] TANC News: September

New publications, TANC at ECC 2011, DIFMAT, popular science...

2011-10-12

[sysmo] Welcome to Claudia D'Ambrosio

Claudia D'Ambrosio has just joined the Lix, as CNRS junior researcher. She will work in the Sysmo team, welcome to her!

2011-10-04

[Infolix] Offre d'emploi dans le projet MaGiX / Job offer in MaGiX project

2011-09-08

[Infolix]Journées communes LAC-GEOCAL. 24 et 25 novembre (changement des dates)

+++++++++++++++++++++++++++++++++++++++ +++ ATTENTION: Changement des dates +++ +++ 24 et 25 novembre 2011 +++ +++++++++++++++++++++++++++++++++++++++ Bonjour à tous, Les groupes de travail GEOCAL (Géométrie du calcul) et LAC (Logique, Algèbre et Calcul) du GDR Informatique mathématique organisent une rencontre commune les Jeudi 24 et Vendredi 25 Novembre 2011 à l'Ecole Polytechnique, Palaiseau. GEOCAL: http://iml.univ-mrs.fr/~regnier/gdr-im/ LAC: http://www.pps.jussieu.fr/~kesner/gdr/lac.html Vous pouvez dès à présent réserver ces journées. On a changé les dates pour éviter un conflict avec la réunion "Operads and Rewriting" à Lyon. Une ébauche de site va progressivement s'enrichir à l'adresse http://www.lix.polytechnique.fr/~lengrand/Events/LACGeoCal/ notamment avec la possibilité de s'y inscrire en ligne. La clôture des inscriptions avec proposition d'exposé est fixée au 1er Novembre 2011, et celle des inscriptions sans proposition d'exposé est fixée au 15 Novembre. L'inscription est gratuite et vous permet de participer gratuitement aux repas organisés. N'hésitez pas à nous contacter si vous avez besoin d'informations supplémentaires. En espérant vous voir nombreux, Bien cordialement, Stéphane Lengrand & Lutz Strassburger, organisateurs, LIX

2011-09-08

[hipercom] New Arrival: Aline Carneiro Viana

We're excited to welcome our newest colleague and collaborator, Aline. A staff research scientist from INRIA, we're looking forward to her company for (we hope) many years to come.

Not only does Aline's arrival brings an excellent scientific mind to the group, but her arrival also adds a new country - Brazil - to the team world map, which now includes colleagues from countries as diverse as Brazil, China, Germany, Corsica, Denmark and (of course) France.

Welcome Aline! We're excited to have you among us.

+ More

2011-09-01

[hipercom] "Building a Subversive Grassroots Network" - IEEE Spectrum talking about OLSR

OLSR is one of our success stories, and it keeps getting (good) press.

This time, the IEEE Spectrum runs a story on using MANETs and OLSR for building subversive networks, bypassing the Internet where either no Internet is available - or is filtered or suspended by oppressive authorities.

We've been talking about this use of OLSR for many years. In the context of the French HADOPI law for filtering and policing the Internet, as well as in the context of the "right of the individual in the digital society, Thomas Clausen gave talks in 2009 and 2010 before two commissions of the French National Assembly. He was presenting such "subversive networks" as a likely outcome of too strict legislation and policing of the Internet, as well as of too invasive tracking of the activities of individuals on the Internet (see Audition of T. Clausen in the context of the HADOPI law "favorisant la diffusion et la protection de la creation sur internet" as well as Audition of T. Clausen in the context of the "Mission d'information commune sur les droits de l'individu dans la révolution numérique").

Any initiative promoting OLSR is good news - for more information about our OLSR activities:

OLSRv2 Standardization
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2011-08-31

[hipercom] Thomas Clausen, Jiazi Yi and Axel Colin de Verdiere at the 81'th IETF in Quebec City

Better late then never with a newsflash.

This IETF saw progress on our currently main MANET protocol, OLSRv2 - now with metrics support, as well as with various MANET security extension and management components. Notably, the security extension to RFC5444 is entering the final phases of standardization, and the security extension to RFC6130 (NHDP) is becoming adopted as a working group item - bringing it that much closer to becoming standardized.

Aside from MANET, the main topic for us at this IETF was Sensor Networks, also known as Low-power Lossy Networks, where we are preparing the ground for some interesting new work.

All in all an extremely busy, but also productive, week.
+ More

2011-08-11

[Infolix]Fwd: [gt-geocal] Journées communes LAC-GEOCAL. 3 et 4 Novembre

Début du message réexpédié :

De : "Stephane Lengrand (Work)" <lengrand@lix.polytechnique.fr>
Date : 11 juillet 2011 15:08:58 HAEC
À : gt-geocal@gdr-im.fr, gt-lac@gdr-im.fr
Objet : [gt-geocal] Journées communes LAC-GEOCAL. 3 et 4 Novembre
Répondre à : lengrand@lix.polytechnique.fr

Bonjour à tous,

Les groupes de travail GEOCAL (Géométrie du calcul) et LAC (Logique,
Algèbre et Calcul) du GDR Informatique mathématique organisent une
rencontre commune les

Jeudi 3 et Vendredi 4 Novembre 2011

à l'Ecole Polytechnique, Palaiseau.

GEOCAL: http://iml.univ-mrs.fr/~regnier/gdr-im/
LAC: http://www.pps.jussieu.fr/~kesner/gdr/lac.html

Vous pouvez dès à présent réservez ces journées.

Une ébauche de site va progressivement s'enrichir à l'adresse

http://www.lix.polytechnique.fr/~lengrand/Events/LACGeoCal/

notamment avec la possibilité de s'y inscrire en ligne. En attendant
vous pouvez déjà vous inscrire en envoyant un email à
lengrand@lix.polytechnique.fr

La clôture des inscriptions avec proposition d'exposé est fixée au 1er
Octobre 2011, et celle des inscriptions sans proposition d'exposé est
fixée au 8 Octobre.
L'inscription est gratuite et vous permet de participer gratuitement aux
repas organisés.

N'hésitez pas à nous contacter si vous avez besoin d'informations
supplémentaires.

En espérant vous voir nombreux,

Bien cordialement,

Stéphane Lengrand & Lutz Strassburger,
organisateurs, LIX

2011-08-02

[Infolix]Fwd: [LABOLIX] [MaGiX@LiX] conférence du LIX en septembre, deuxième annonce

Début du message réexpédié :

De : Joris van der Hoeven <vdhoeven@lix.polytechnique.fr>
Objet : [LABOLIX] [MaGiX@LiX] conférence du LIX en septembre, deuxième annonce
Date : 12 juillet 2011 14:44:21 HAEC
À : labolix@lix.polytechnique.fr

Bonjour,

Le programme prévisionnel de la conférence du labo MaGiX@LiX est désormais en ligne :

http://magix.lix.polytechnique.fr/magixalix-participants.en.html

Les personnes du labo qui désirent participer à l'excursion le mercredi
sont invitées a s'inscrire ici :

https://www.lix.polytechnique.fr/~dndiatta/magix2011/registration_participant.php

Bien cordialement,

--Joris

------------------------------------------------------------------------

Announcement
------------

We are pleased to announce the MaGiX@LiX conference which will take
place at the Ecole polytechnique, Palaiseau, France during the week
from september 19 until september 24 this year. The conference aims at
bringing together experts and developers of mathematical software in
the areas of computer algebra, reliable analysis, language design and
interfaces. Most of the talks and software demonstrations should be
accessible for non experts in these areas. For more information, see:

http://magix.lix.polytechnique.fr/magixalix.en.html

Invited speakers
----------------

* Martin Berz, Kyoko Makino
* François Boulier
* Quentin Carbonneaux, François Clément, Pierre Weis
* Gabriel Dos Reis
* Jean-Charles Faugère
* Mickael Gastineau, Jacques Laskar
* Claude Gomez, Serge Steer
* Daniel R. Grayson
* Massimiliano Gubinelli
* William B. Hart
* Grégoire Lecerf
* François Lemaire
* Angelos Manzaflaris
* Marc Moreno Maza
* Bernard Mourrain
* Jean-Michel Müller
* Marc Pouzet
* Fabrice Rouillier
* Marie Françoise Roy
* Mohab Safey el Din
* Hans Schönemann
* Damien Stehlé
* Emmanuel Thomé
* Joris van der Hoeven
* Éric Walter
* Stephen Watt
* Klaus Weihrauch
* Paul Zimmermann

Detailed Scope
--------------

Nowadays, two kinds of mathematical computation systems have met
a great success. Historically, we find numerical computation systems,
such as Matlab, Octave or Scilab. These systems allow for the approximate
resolution of analytic problems, such as the integration of differential
equations. On the other hand, we find symbolic computation systems,
such as Mathematica, Maple, Axiom, Singular or more recently Sage.

In the MaGiX project, we intend to transpose the computer algebra spirit
of exact mathematical computations to analytic problems. In order to
achieve this goal, techniques from various areas need to be combined.
Besides computer algebra and reliable computation, we also need an adequate
mathematical programming language which is sufficiently efficient for
numerical computations. Since the ultimate goal is to develop a user friendly
and general purpose system for algebraic and analytic computations, nice user
interfaces are also an important issue.

The MaGiX@LiX conference therefore aims to bring together developers and
users of mathematical software in the areas of computer algebra,
reliable numeric computation, user interfaces and mathematical programming
languages. The conference consists of a mixture of software demos and talks
which provide some of the scientific background. Most talks are intended
to be introductory and suitable for non experts in the specific areas.

Sponsors
--------

* ANR grant ANR-09-JCJC-0098-01 MaGiX
* LIX, the CNRS Computer Science Laboratory of the Ecole polytechnique

2011-08-02

[Infolix]Fwd: [LABOLIX] Soutenance de thèse / Thesis defense - Mahsa BEHZADI 12 July 15:00 Amp hi Becquerel

Début du message réexpédié :

De : behzadim@lix.polytechnique.fr
Date : 1 juillet 2011 15:53:15 HAEC
À : labolix@lix.polytechnique.fr
Objet : [LABOLIX] Soutenance de thèse / Thesis defense - Mahsa BEHZADI 12 July 15:00 Amp hi Becquerel

Bonjour,

J'ai le plaisir du vous inviter à ma soutenance de thèse

      "A Mathematical Model of Phospholipid Biosynthesis"

qui se déroulera le

                  mardi 12 juillet 2011 à 15:00

à l'Ecole Polytechnique, amphithéâtre Becquerel, ainsi qu'au pot qui
suivra en salle de réunions du LIX (à 17:00 environ).

La thèse sera soutenue devant le jury composé de

Prof. Jean-Marc Steyaert, directeur de thèse
Prof. Jean-Pierre Mazat, rapporteur
Prof. Gilles Bernot, rapporteur
Prof. Joachim Selbig, rapporteur
Prof. Mireille Regnier, Responsable de l'equipe
Dr. Aicha demidem
Dr. Laurent Schwartz

Pour vous rendre à l'Ecole Polytechnique, Cf :

   http://www.polytechnique.edu/accueil/vie-sur-le-campus/s-orienter-sur-le-campus/s-orienter-5641.kjsp

----------------------------------------------------------------------

Hi,

it is my pleasure to invite you to the defense of my thesis

    "A Mathematical Model of Phospholipid Biosynthesis"

that will take place on

                  Tuesday 12 July 2011 at 15:00

at the Ecole Polytechnique, Becquerel lecture hall, as well as the
ensuing reception which will be around 17:00 in the main meeting room of
LIX (Computer Science Lab).

This thesis will be defended before the following jury :

Prof. Jean-Marc Steyaert, Thesis advisor
Prof. Jean-Pierre Mazat, Reviewer
Prof. Gilles Bernot, Reviewer
Prof. Joachim Selbig, Reviewer
Prof. Mireille Regnier, Head of the group
Dr. Aicha demidem
Dr. Laurent Schwartz

To get to École Polytechnique:

   http://www.polytechnique.edu/accueil/vie-sur-le-campus/s-orienter-sur-le-campus/s-orienter-5641.kjsp

------------------------------------------------------------

The central topic of this study is the mathematical modeling of the
phospholipid biosynthesis. A dynamic, continuous and deterministic
modelingd metabolicpathway; the temporal changes of metabolites are
formulated asapproach is chosen to represent the behavior of the
phospholipi a genericset of ODEs. Next we apply this model to dierent
experimental datasets inn process, followed by the mathematical simulation
of the modeland nally a healthy and tumoral cells; each of these
applications consists of a parameterestimatioset of analyses such as
stability analysis or sensitivity analysis.

2011-08-02

[Infolix]Fwd: Commande automatisée d'un procédé : le projet ALIEN primé par le Concours national d'aide à la création d'entreprises de technologies innovantes

Début du message réexpédié :

Date : 4 juillet 2011 10:20:34 HAEC
Objet : Commande automatisée d'un procédé : le projet ALIEN primé par le Concours national d'aide à la création d'entreprises de technologies innovantes
Source: Institut des sciences informatiques et de leurs interactions - CNRS
Auteur: Jean-Baptiste Pressac

Dans le cadre de la politique de soutien à l'innovation, la ministre de l'Enseignement supérieur et de la Recherche, Valérie Pécresse, a remis, le 28 juin, les prix de l'édition 2011 du Concours national d'aide à la création d'entreprises de technologies innovantes. Le projet ALIEN, porté par Cédric Join du CRAN (CNRS/Université Nancy 1/INPL Nancy) et Michel Fliess du LIX (CNRS/Ecole Polytechnique), est lauréat du concours dans la catégorie Émergence.
Depuis 13 ans, le Concours national d'aide à la création d'entreprises de technologies innovantes détecte et apporte un soutien financier à des projets de création d'entreprises innovantes. Le concours comprend deux catégories : les projets « en émergence » qui nécessitent encore une phase de maturation, et les projets « création-développement » dont la preuve du concept est déjà établie et qui donnent lieu à une création d'entreprise.
Sélectionné dans la catégorie Emergence, le projet ALIEN propose un nouveau type de commande des systèmes complexes, la commande sans modèle ou CSM.
La CSM est capable de contrôler des systèmes complexes sans avoir besoin d'une modélisation mathématique précise, difficile - voire impossible- à obtenir. Cette loi de commande est, donc, indépendante de la structure mathématique, mal connue, du dispositif à commander. Elle peut être considérée comme une commande universelle des systèmes.
Ses performances, comme le temps de réponse, les dépassements, le rejet des perturbations, sont excellentes. Sa mise en oeuvre est aisée et ne nécessite pas une grande puissance de calcul. Cette stratégie de commande permettra de réguler de façon efficace des dispositifs complexes, issus des domaines les plus divers qui, jusqu'alors, n'avaient pu l'être. Elle a déjà démontré une grande efficacité dans des domaines industriels variés, allant de la régulation de moteurs à celle du trafic routier, en passant par les aménagements hydro-électriques et l'électronique de puissance.
En savoir plus
En savoir plus…

2011-08-02

[hipercom] New book: "Introduction à la science informatique"

Hipercom@LIX faculty and researchers have, under the direction of Gilles Dowek (INRIA), been authoring the networking related parts of a newly published book "Introduction à la science informatique".

Intended as a textbook for high-school teachers, preparing to teach the new speciality "Informatique et sciences du numérique" starting in 2012, this book not only explains the fundamentals in computer science and computer networking in an accessible fashion, but also muses on proper didactic approaches for teaching these subjects at the high-school level.
+ More

2011-07-25

[tanc] TANC News: June

Jérôme Milan's TIFA package for integer factorization was released, and presented at the 2011 Teratec Forum.

Ben Smith spoke about accelerated point counting on genus 2 curves with explicit Real Multiplication at the GeoCrypt 2011 conference. This new algorithm, joint work with Pierrick Gaudry (CARAMEL/LORIA) and David Kohel (Luminy), has been used to completely smash the previous world record for genus 2 point counting in large characteristic. A preprint is now on the arXiv.

2011-07-06

Concours externe CNRS: un poste d'administrateur systèmes et réseaux ouvert au LIX

= Activités = * Choix, organisation, mise en place ou à niveau des éléments matériels et logiciels des systèmes informatiques du laboratoire, en fonction des besoins des utilisateurs et des impératifs de sécurité. * Conseil, suivi, et formation des utilisateurs. * Maintenir et développer les outils d’administration propre au site, participer au développement du web. * Administration, suivi et développements des systèmes informatiques du laboratoire. * Animation du comité de suivi utilisateurs/administrateurs * Évolution du système informatique = Compétences = * Très bonne connaissances des environnements Linux. Maîtrise des systèmes Mac OS et Windows. * Connaître et savoir exploiter des services tels que Postfix, NIS, LDAP, KERBEROS, NFS, le SAN, le iSCSI, et les technologies de cluster. * Connaitre le Python et les systèmes REDHAT/ CENTOS / FEDORA * Autonomie * Anglais lu et parlé souhaité * Goût pour le travail en équipe et la nouveauté = Contexte = Le LIX (http://www.lix.polytechnique.fr/) est situé sur le site de l’École Polytechnique. L’agent sera affecté au sein de l’équipe système (1 autre personne) qui est directement rattachée à la direction du laboratoire. Le travail se fera en relation avec les services informatiques de l’École Polytechnique qui gèrent le réseau. Le système d’information du laboratoire est homologué CATI.

2011-07-05

[tanc] Algorithms for Curves, Moduli, and Isogenies

Thursday, July 7, 2011
Amphithéatre Becquerel, École polytechnique
[Program|Abstracts|Logistics]

Program

10h30—11h00: Meeting, coffee
11h00—12h00: Ben Smith (LIX/INRIA Saclay/LIX)
Point Counting for Genus 2 Curves with Real Multiplication Abstract

12h00—13h30: Lunch

13h30—14h30: Kamal Khuri-Makdisi (American University of Beirut)
Using algebraic values of modular forms to obtain models for modular curves Abstract

14h30—15h00: Coffee break

15h00—16h00: David Gruenewald (Université de Caen Basse Normandie)
Computing “isogeny graphs” using CM lattices Abstract

2011-07-01

[hipercom] Thursday 16/6 at 18h: Talk by dr. Tiziana Refice on networking research at Google,

Dr. Refice will present some of the interesting networking research activities that Google is pursuing, including in particular M-Lab.

M-Lab is an open distributed server platform to deploy network measurement tools, a collection of open-source tools and an open repository of data - all publicly available.

The seminar is Thursday June 16 at 18h at "Amphithéâtre Becquerel", and is intended for both faculty, research staff, post.docs, undergraduate and graduate students.

I believe that it may be especially interesting for undergraduate and graduate students, contemplating what interesting careers may lie ahead also in industry, as well as for faculty and research staff wondering what collaborative options Google may harbor in the distributed computing and computer networking area.

Show up to get a very unique chance to get a look into the ground-breaking work that Google is doing, to talk with a googler and ask all the questions you've ever wanted to ask from a googler (and, maybe, get some answers too)!
+ More

2011-06-16

[tanc] Tools for Integer Factorization: TIFA now online

Jerome Milan's TIFA package ("Tools for Integer FActorization") is now available online. TIFA is an open source library for factoring small to medium-sized composite integers (from 40 to 200 bits, say).

2011-06-14

[hipercom] New Arrival: Alberto Camacho Martinez

Better late than never, I suppose, but we're excited to count Alberto Camacho Martinez among us. He is staying with us for a semester (at least), after which Alberto will graduate from a joint multidisciplinar program in Telecommunication Engineering and Mathematics in the UPC, Spain.

2011-06-11

[Infolix] Comete-Parsifal Seminar Tue Jun 07, 14:30

De : Andrés A. Aristizábal P. <andresaristi@lix.polytechnique.fr>
Date : 6 juin 2011 10:30:32 HAEC
À : romain.beauxis@gmail.com, comete@lix.polytechnique.fr, parsifal@lix.polytechnique.fr, labolix@lix.polytechnique.fr
Objet : [LABOLIX] Reminder: Comete-Parsifal Seminar Tue Jun 07, 14:30

Comete-Parsifal Seminar

Tue Jun 07, 14:30
                LIX, Ecole Polytechnique
           Salle de Reunion, LIX
        http://www.lix.polytechnique.fr/comete/seminar/

Title: The Failure of Noise-Based Non-Continuous Audio Captchas.
Speaker: Romain Beauxis.
Abstract:
CAPTCHAs, which are automated tests intended to distinguish humans from
programs, are used on many web sites to prevent bot-based account creation
and spam. To avoid imposing undue user friction, CAPTCHAs must be easy for
humans and difficult for machines. However, the
scientific basis for successful CAPTCHA design is still emerging.
In this talk, we will examine the widely used class of audio CAPTCHAs
based on distorting non-continuous speech with certain classes of
noise and demonstrates that virtually all current schemes, including ones
from Microsoft, Yahoo, and eBay, are easily broken.
More generally, we describe a set of fundamental techniques, packaged
together in our Decaptcha system, that effectively defeat
a wide class of audio CAPTCHAs based on non-continuous speech.
Decaptcha's performance on actual observed and synthetic CAPTCHAs
indicates that such speech CAPTCHAs are inherently weak and, because of
the importance of audio for various classes of users, alternative audio
CAPTCHAs must be developed.

--
Andrés A. Aristizábal P.
PhD Student
École Polytechnique
Ingeniero de Sistemas y Computación
Pontificia Universidad Javeriana Cali
Especialista en Periodismo
Universidad de los Andes Bogotá

2011-06-06

[tanc] TANC News: May

May Events

Daniel Augot gave a presentation ("Qu'est-ce qu'un matheux?") at Scube.

Ben Smith visited the CARAMEL project in Nancy, and gave a talk about geometric algorithms for low-degree isogenies in genus 2. He also gave two talks at the Elliptic Curve Discrete Logarithm Problem workshop at EPFL's Laboratory for Cryptologic Algorithms (LACAL): a general introduction to the arithmetic of hyperelliptic curves, and a technical talk on the isogeny attack in genus 3.

2011-06-02

[hipercom] Congratulations, dr. Herberg

On Friday, may 20, Ulrich stopped being mr. Herberg, to become dr. Herberg upon successfully defending the manuscript "Performance, Scalability, Automatic Management and Internet Integration of Ad Hoc Networks".

Ulrich - sorry, dr. Herberg - defended before a jury composed by Michel Diaz (LAAS-CNRS, rapporteur), Joseph Macker (NRL, rapporteur), Robert G. Cole (US Army), Walid Dabbous (INRIA), Christoper Dearlove (BAE Systems), Philippe Jacquet (INRIA) and Thomas Clausen (Ecole Polytechnique. Additionally, Kenichi Mase (Niigata University) was rapporteur on this manuscript.

Hipercom@LIX joins in congratulating dr. Herberg, and wishing him all our best.
+ More

2011-05-23

Dernière minute: un poste d'AI disponible sur NOEMI

Pour plus d'informations, voir la [[http://web-rh.dsi.cnrs.fr/afip/owa/consult.affiche_fonc?code_fonc=Q61005&code_corps=&code_dr=&code_bap=&code_ds=61&nbjours=1|fiche de poste]] sur le site du CNRS. = Mission = L'assistant(e) réalise et coordonne les activités administratives de l'unité. = Activités = * Elaborer des actes sur l'ensemble des domaines de gestion (gestion administrative, financière et comptable, encadrement des personnels). * Suivre l'évolution de la réglementation sur l'ensemble des domaines de gestion. * Assurer la gestion financière du laboratoire : préparation, mise en oeuvre et suivi de l'exécution du budget du laboratoire. * Etablir des bilans financiers et analyser les dépenses. * Contrôler l’exécution du budget et des justifications financières des contrats de recherche. * Préparer et diffuser les comptes rendus. * Mettre en œuvre l’organisation matérielle de réunions et de colloques. * Accueillir, informer et orienter dans les démarches administratives les visiteurs et les personnels de l’unité. * Participer à la mise à jour des bases de données documentaires de l’unité. * Contribuer à la réalisation de rapports documentaires et réponses aux enquêtes. = Compétences = * Connaître les bases des statuts de la fonction publique, des EPST et du CNRS notamment. * Maîtriser les réglementations financières, comptables et des marchés publics. * Maîtriser l’environnement bureautique et les outils informatiques appliqués à la gestion. * Savoir analyser la gestion pour en dégager les indicateurs. * Appliquer et faire appliquer les textes réglementaires dans le contexte de l’unité. * Rédiger des notes d’informations et des actes administratifs. * Connaître l'anglais écrit et oral. * Savoir planifier les activités et les échéances. * Etre autonome dans la gestion des dossiers tout en sachant rendre compte à sa hiérarchie. * Savoir manifester un fort esprit d’équipe. = Contexte de travail = L’activité s’exerce dans une UMR du CNRS qui compte plus de 100 personnes. Ses membres viennent du CNRS, de l’INRIA, du CEA et de l’Ecole Polytechnique. Il/elle assurera une double fonction : Assistant(e) en équipe dans l’équipe de Direction du Laboratoire et Assistant(e) de plusieurs équipes de recherche du laboratoire.

2011-05-21

[Infolix] [[A-team] ] seminar Thursday

De : Jan Foniok <foniok@lix.polytechnique.fr>
Date : 9 mai 2011 14:20:11 HAEC
À : a-team <a-team@lix.polytechnique.fr>, Jaroslav Nešetřil <nesetril@kam.mff.cuni.cz>, Patrice Ossona de Mendez <pom@ehess.fr>
Objet : [[A-team] ] seminar Thursday

Dear A-team & friends,

on Thursday (12 May) at 1400 I will give a talk in the “Séminaire de Combinatoire Algébrique et Géométrique”. The seminar takes place in Jussieu, 4 place Jussieu, Paris 5e, en salle 15-16 101 (1er étage).

Title: Adjoint functors on digraphs

Abstract: After explaining what they are, I will discuss how adjoint functors on digraphs can be used as a tool for proving the non-existence of homomorphisms. Applications include polynomial testing of the existence of a homomorphism (constraint satisfaction), a rich common structure of non-3-colourable digraphs, and some observations related to Hedetniemi's conjecture about the chromatic number of products.

http://www.ecp6.jussieu.fr/seminaire/annonces.html

Jan

2011-05-12

[tanc] TANC News: April

TANC welcomes Cécile Gonçalves and Tania Richmond; Iwan Duursma visits; two new publications; and other news.

2011-05-12

[Fwd: DenyHosts Report from hammer.lix.polytechnique.fr]

-- James

2011-05-11

Campagne NOEMI: un poste ouvert au sein de MAX, HIPERCOM ou COMETE

Description du poste

Emploi-type: Chef de projet ou expert en développement et déploiement d'application

Mission:Le chef de projet ou l’expert en développement d’applications conduit la maîtrise d’œuvre des projets de développement. Il sera responsable de la réalisation du projet, et de son adéquation aux besoins des utilisateurs. Il pourra être fortement impliqué dans l’activité de recherche du domaine scientifique concerné et dans les développements de logiciels associés, avec un équilibre variable entre les deux.

Activités

L’ingénieur de recherche recruté sera affecté à l’une des équipes de recherche du laboratoire LIX. Les équipes MAX, HIPERCOM et COMETE font partie des équipes prioritaires.

Ses missions incluront :

Formaliser, ou aider des chercheurs à formaliser un problème scientifique, pour sa modélisation, sa représentation, et son traitement Choisir les moyens logiciels et matériels, en tenant compte de leurs performances et de leur pertinence dans le cadre d’un problème donné ou d’un projet de recherche.
Participer au développement des logiciels et de leur portage sur les principales architectures et systèmes d'exploitation.
Mettre en œuvre des systèmes automatiques pour tester les logiciels et les distribuer.
Conduire un projet technique qui concourt à la résolution d’une problématique scientifique dans ses dimensions techniques, humaines et administratives
Pour l’équipe MAX : concevoir, développer ou adapter des méthodes de calcul formel (algèbre) et de calcul numérique certifié (analyse), symbolique, résolution de système d'équations différentielles explicites ou implicites.
Pour l’équipe HIPERCOM : maintenir et contribuer au développement d’outils logiciels de l’équipe. Maintenir, documenter du code informatique en utilisant les outils modernes de gestion de partage et de mise à disposition.

Activités associées

Assurer une veille technologique sur l’évolution des architectures matérielles, des systèmes, et des concepts associés
Assurer une veille scientifique sur l’évolution des concepts et des méthodes dans les domaines d’application
S’impliquer dans un réseau de compétence
Former et assurer le transfert des connaissances et des savoir-faire : participer à la formation des utilisateurs, diffuser et valoriser les méthodes et outils développés
Participer au choix, à l’acquisition, et à l’exploitation de calculateurs haute performance
Encadrer et animer une équipe d’ingénieurs et techniciens
Représenter son organisme auprès de différents publics nationaux ou internationaux
Pour l’intégration dans MAX : Concevoir, développer ou adapter des méthodes d’analyse: calcul numérique certifié, symbolique, résolution de système d'équations différentielles explicites ou implicites.

Compétences principales

Savoirs généraux, théoriques ou disciplinaires

Connaissance approfondie des techniques de programmation et d’optimisation
Connaissance générale des architectures des ordinateurs, des systèmes distribués et des systèmes d’exploitation
En liens avec l’équipe MAX :
- Connaissances en mathématiques appliquées, principalement en algèbre et en analyse numérique certifiée.
- Connaissance générale de bibliothèques de programmes de calcul numérique et formel
- Connaissance des domaines d’utilisation du calcul symbolique et numérique, dans la recherche comme dans les domaines techniques industriels

Savoir-faire opérationnels

Intégrer dans ses activités les évolutions des méthodes informatiques et mathématiques, et de la discipline d’application
Maîtriser des langages de programmation, dont le langage C++ Travailler en interaction avec une ou plusieurs équipes de recherche Maîtriser des méthodologies de conduite de projet
Pour l’équipe MAX : Connaître les techniques algorithmiques élémentaires sur les objets de base comme les polynômes, les séries, les matrices etc ...

Compétences linguistiques

Anglais : Expression écrite et orale : niveau 2

2011-05-11

Fwd: [LABOLIX] Pretty Structures 2011: a l'IHP, 2-6 mai

De : Leo Liberti <liberti@lix.polytechnique.fr>
Date : 29 avril 2011 09:21:59 HAEC
À : labolix@lix.polytechnique.fr
Objet : [LABOLIX] Pretty Structures 2011: a l'IHP, 2-6 mai

Hi everyone,

please attend the "Pretty Structures 2011" seminar at the Institut Henri Poincare (Paris, 5eme arr), from 2 to 6 may 2011.

http://www.lix.polytechnique.fr/~liberti/pretty_structures/

Among the speakers, Jack Edmonds. Last time he brought a soundtrack to speak upon. Come see the show! ;-)

Ciao

Leo

2011-04-29

Fwd: LIX-Qualcomm Fellowship / Postdoc au LIX

De : Olivier Bournez <olivier.bournez@gmail.com>
Date : 20 avril 2011 11:42:58 HAEC
À : alp-diffusion@univ-lille1.fr
Objet : LIX-Qualcomm Fellowship / Postdoc au LIX

Rappel: Le LIX propose un financement de postdoc (LIX-Qualcomm Fellowship) ouvert à toutes les thématiques présentes au LIX.

Date limite: VENDREDI 29 AVRIL = La semaine prochaine.

   http://www.lix.polytechnique.fr/fellowship/

Svp transmettez aux candidats potentiels.

======

Reminder: The LIX Laboratory propose a postdoc fellowship (LIX-Qualcomm Fellowship) open to all thematics present in the lab.

Deadline: FRIDAY APRIL 29th = Next week.

   http://www.lix.polytechnique.fr/fellowship/

Please forward to potential candidates.

===

ENGLISH ANNOUCEMENT:

LIX, the Laboratory for Computer Science at the Ecole Polytechnique, France, is inviting applications for its 2011-2012 LIX-Qualcomm Postdoctoral Fellowship for research in computer science.

   http://www.lix.polytechnique.fr/fellowship

LIX offers a unique academic research environment, bringing together permanent staff researchers from CNRS, INRIA, and CEA, as well as resident faculty from Ecole Polytechnique. We encourage a mixture of theoretical, applied, and experimental research. Including academic visitors, postdoctoral fellows and PhD students, LIX is home to about 120 researchers, organized in 11 research teams on the following subjects:

   * Wireless and Ad Hoc Networking
   * Computer Graphics, Vision and Visual Computing
   * Bioinformatics
   * Algorithms, Optimization
   * Formal Languages for Mobile and Distributed Systems
   * Reliability and Safety of Software
   * Complex Systems
   * Combinatorics
   * Algebraic Modelization
   * Cryptology and Coding Theory
   * Automatic Proof Processing
   * Algorithms for Distributed Systems
   * Operations Research
   * Algorithmic Game Theory
   * Models for Continuous Time Computations
   * Complexity
   * Constraint Satisfaction Problems

Further information about the research teams at LIX can be found at
   http://www.lix.polytechnique.fr/

The LIX-Qualcomm postdoctoral fellowship provides young scientists of outstanding quality an opportunity to advance their academic career as resident research fellows in one of these 11 research teams. The fellow is free to continue his/her own research, however expected to identify and integrate with a LIX research team in his/her area of interest. Applicants are strongly encouraged to solicit contact with staff researchers in their team(s) of research in advance.

The fellowship will be for one year, with an opportunity for a fellow to present candidature for renewal for one additional year. The fellowship is supported by a competitive stipend. Applicants must have received a PhD degree after January 2010 or should expect to receive one before the fellowship commences in fall 2011.

Applications will be accepted until Friday April 29, 2011, and must be submitted on-line. Further details on the fellowship, and the application procedure, can be found at
   http://www.lix.polytechnique.fr/fellowship

===

ANNONCE EN FRANCAIS:

Le LIX, le Laboratoire d'Informatique de l'Ecole polytechnique, sollicite des candidatures pour un financement postdoctoral

   2011-2012 LIX-Qualcomm Postdoctoral Fellowship

de recherche en informatique.

   http://www.lix.polytechnique.fr/fellowship

LIX offre un environnement de recherche unique, réunissant des chercheurs permanents du CNRS, l'INRIA, du CEA, ainsi que des enseignants chercheurs de l'Ecole polytechnique.

Ce financement postdoctoral est ouvert à toutes les thématiques présentes au laboratoire: http://www.lix.polytechnique.fr et http://www.lix.polytechnique.fr/fellowship

Le ou la postdoc sera libre de prolonger ses propres recherches, du moment qu'elles s'intègrent avec une équipe de recherche présente au laboratoire dans son domaine de recherche. Les candidat(e)s sont fortement invité(e)s à contacter les chercheurs du laboratoire par avance.

Le financement est pour une année, avec possibilité éventuelle de renouvellement pour une année supplémentaire.

Le(s) candidat(e)(s) seront sélectionné(e)s par un comité de sélection parmi les candidatures reçues. Les candidat(e)s devront avoir soutenu leur thèse après janvier 2010 ou avant la date prévue de début du postdoc à l'automne 2011.

La date limite pour proposer sa candidature est le Vendredi 29 Avril 2011. Les candidatures doivent être déposées en ligne.

Tous les détails sur   http://www.lix.polytechnique.fr/fellowship

2011-04-20

Postdoc position in proof theory in Paris

De : Lutz Strassburger <lutz@lix.polytechnique.fr>
Date : 20 avril 2011 10:19:09 HAEC
À : gdr-im@gdr-im.fr
Objet : [gdr-im] Postdoc position in proof theory in Paris

--------------------------------------------------------
Postdoc position in proof theory in Paris
--------------------------------------------------------

There is an opening of a postdoc position on structural and
computational proof theory. The position is financed by
the ANR within the project STRUCTURAL
<http://www.lix.polytechnique.fr/~lutz/orgs/structural.html>

The postdoc will be hosted by the Laboratoire d'Informatique (LIX) at
the Ecole Polytechnique, one of the "Grand Ecoles" in the French
university system, located in the suburbs of Paris.

Applicants must have a Ph.D. or equivalent in computer science or
mathematics, and should have a strong background in proof theory
and related topics. The principal responsibility of the postdoc
will be to carry out research in the area of proof theory within the
project STRUCTURAL. There are no teaching duties.

For further information, see
<http://www.lix.polytechnique.fr/~lutz/orgs/structural-postdoc.html>

or contact
Lutz Strassburger <lutz@lix.polytechnique.fr>
or
Kaustuv Chaudhuri <kaustuv.chaudhuri@inria.fr>

Applications should be sent via email to Lutz Strassburger
<lutz@lix.polytechnique.fr> and Kaustuv Chaudhuri
<kaustuv.chaudhuri@inria.fr>, and should include a CV, a research
statement (1-2 pages), and two recommendation letters. The application
deadline is

*** May 20, 2011 ***

2011-04-20

[hipercom] New Arrival - Axel Colin de Verdiere

Axel is a student from the Ecole Polytechnique (X08), currently specializing in computer science. Having followed an M1 in computer networking, he has joined Hipercom@LIX as a research intern, working on routing protocols for sensor networks for about 4 months.

2011-04-19

[hipercom] New Arrival: Ming-Chih Chien

Ming-Chih is a College Student from National Taiwan University, participating in International Exchange Program 2010-2011 with Ecole Polytechnque.

He has joined Hipeercom@LIX for an internship for one semester, during which he will be working on, among other things, multipath routing in MANETs

2011-04-19

[hipercom] 2:46: Aftershocks: Stories from the Japan Earthquake (Book)

The Twitter-sourced book "2:46: Aftershocks: Stories from the Japan Earthquake" is now available. The book is personal recollections and photos from both foreigners and Japanese in the hours and days following Japan's 9.0 earthquake, tsunami and ongoing nuclear emergency.

All of the proceeds from the book go to the Japan Red Cross. The book is available in digital form, for Kindle, Mac, PC, iPad, and smartphones.

Our current guest, Rodney Van Meter, is among the contributors to this work.

Our thoughts go out to our friends and colleagues in Japan.
+ More

2011-04-12

[tanc] We upgrade ourselves !

Crypto@LIX, and TANC, will evolve.

Stay tuned.

2011-02-16

[tanc] Congratulations Luca De Feo

Luca De Feo successfully defended his PhD thesis, Fast algorithms for towers of finite fields and isogenies, on 13/12/2010. He is now working as a postdoctoral researcher at Rennes.

2010-12-14

[tanc] Congratulations Jean-François Biasse

Jean-François Biasse defended his PhD thesis, "Algorithmes sous-exponentiels pour les corps de nombres" on 20/09/2010. He is currently working with the MAGMA group in Sydney.

2010-10-25

[tanc] François Morain at ECC 2010

François Morain was an invited speaker at the 25th anniversary Workshop on Elliptic Curves and Computation.

A video of his talk is available for download here.

2010-10-25

[tanc] François Morain at Pariscience 2010

François Morain was a guest on the discussion panel for the film Cosmic Code Breakers: the Secrets of Prime Numbers at the 2010 Pariscience film festival.

2010-10-25

[sysmo] Alberto Costa is one the 3 winners of the mathematical prize Xavier Gransart!

Alberto Costa, a PhD student from the sysmo team, won the mathematics competition Xavier Grandsart (http://xaviergrandsart.com/concours.htm), ex aequo with Maher YOUNAN (PhD student in physics from Geneva) and Pierre DELIGNE (Fields medal from Princeton).

2010-09-10

[tanc] Cryptography and Coding Theory

The Cryptography and Coding Theory research group at LIX is based around the INRIA Équipe-Projet TANC: Théorie Algebrique de Nombres pour la Cryptologie.

We approach problems in modern Public-Key Cryptography and Coding Theory from the point of view of Algorithmic Arithmetic and Algebraic Geometry, combining sophisticated mathematics with powerful algorithms.

2010-08-10

[tanc] News

François Morain was an invited speaker at the 25th anniversary Workshop on Elliptic Curves and Computation. (more...)

François Morain was on the panel for the film at the 2010 Pariscience film festival. (more...)

2010-08-10

[sysmo] The sysmo@lix team won the EURO/ROADEF Challenge 2010!

A team of researchers at LIX, Ecole Polytechnique (David Savourey, Vincent Jost, Nora Touati, Antoine Jeanjean, Christophe Duerr), all affiliated to the Microsoft-CNRS Chair "Optimization and Sustainable Development" (http://chaire-osd.polytechnique.fr) were awarded the first prize (in the "senior" category) of the ROADEF/EURO Challenge 2010 sponsored by Electricite de France (http://challenge.roadef.org/2010/index.en.htm). The challenge consists in computationally solving a large-scale production management problem with varied constraints. It allows qualified researchers to show their knowledge and demonstrate their know-how on pratical problems, and gives them the opportunity to establish partnerships with industrial companies.

2010-08-01

[sysmo] Conference : Complex System Design and Managment 2010 [27-29oct2010]

Complex Systems Design and Management (CSDM) 2010 is an European academic-industrial conference dedicated to all academic researchers and industrial actors working on complex industrial systems engineering.

2010-07-05

[sysmo] Conference : Toulouse Global Optimization 2010 [31aug-3sep2010]

The Toulouse Global Optimization workshop 2010 (TOGO10) welcomes original contributions in the field of Global Optimization (GO): theory, methods, applications.

2010-06-28

[sysmo] Postdoctoral positions open

The Microsoft Research-CNRS chair ``Optimization for Sustainable Development'' (http://chaire-osd.polytechnique.fr/) at LIX, Ecole Polytechnique (near Paris, France) is inviting applications for two postdoctoral positions in the field of Operations Research applied to Sustainable Development applications.

2010-06-15

[sysmo] European Workshop on Mixed Integer Nonlinear Programming 2010 [12-16apr2010]

Mixed-Integer Nonlinear Programming (MINLP) is a sub-field of Mathematical Programming (MP) specializing in modelling and solving one of the most general (and hard) classes of optimization problems: namely, problems including both nonlinear terms and integer variables. There are countless applications: in energy production, chemical engineering, scheduling, software verification, quantum chemistry, geometry, bioinformatics, nuclear engineering, and water distribution, to name a few. Small and medium scale MINLPs are currently solved using a Branch-and-Bound variant called "spatial Branch-and-Bound" (sBB), where branching is allowed on continuous as well as discrete variables that contribute to the gap between the original problem and its convex relaxation. For large-scale variants one must currently resort to heuristics, such as VNS, Feasibility Pump, Local Branching; or exploit the problem structure to derive special-purpose methods. Numerous individuals within the larger mathematical programming community have recognized MINLP as an important developing area that is likely to continue to grow rapidly in significant in the coming years. A MINLP community is currently forming, including numerous operations researchers with many different backgrounds: chemical engineering, (local) nonlinear programming, global optimization, mixed-integer linear programming, conic programming, and others. This workshop is the European counterpart to the IMA "Hot Topics" MINLP workshop held in Minneapolis, Nov. 2008, and intends to help establish an annual event around which the MINLP community can pool, grow and prosper.

2010-04-01

[sysmo] 6th Optimeo day at Lix

http://www.lix.polytechnique.fr/~liberti/optimeo10/

2010-03-02

[typical] Welcome !

TypiCal stands for Types, logic and Calculus. It is a project founded by INRIA Saclay, and is located at École Polytechnique, France.

2009-02-06