École normale supérieure de Cachan

About: École normale supérieure de Cachan is a education organization based out in Cachan, Île-de-France, France. It is known for research contribution in the topics: Decidability & Finite element method. The organization has 2717 authors who have published 5585 publications receiving 175925 citations.

Dithiazolylethene-based molecular switches for nonlinear optical properties and fluorescence: synthesis, crystal structure and ligating properties

Abstract: Two photochromic dithiazolylethene-based derivatives (1a and 2a) incorporating a push–pull structural motif D–π–A are synthesized and structurally characterized. The photochemical reactions, which reversibly modify the connection between the electron donor and acceptor, result in simultaneous and effective photo-modulations of their NLO and fluorescent properties. The photo-switchable NLO behaviors are investigated theoretically by performing INDO calculations. The presence of chelating sites in 2a allows the synthesis of various metal complexes: Cu(hfac)2·2a, Mn(hfac)2·2a and Ag(2a)2CF3SO3. Their crystal structures are determined.

Prescribing the Jacobian determinant in Sobolev spaces

Abstract: Let Ω be a bounded domain in R n with regular boundary. In this paper, we study the equations of the type det (∇ u ( x )) = f in Ω and u ( x ) = x on ∂Ω where f lies in some Sobolev spaces. We establish some existence and non-existence results. A discussion of general cases is also included.

Static analysis of active XML systems

Abstract: Active XML is a high-level specification language tailored to data-intensive, distributed, dynamic Web services. Active XML is based on XML documents with embedded function calls. The state of a document evolves depending on the result of internal function calls (local computations) or external ones (interactions with users or other services). Function calls return documents that may be active, and so may activate new subtasks. The focus of this article is on the verification of temporal properties of runs of Active XML systems, specified in a tree-pattern-based temporal logic, Tree-LTL, which allows expressing a rich class of semantic properties of the application. The main results establish the boundary of decidability and the complexity of automatic verification of Tree-LTL properties.

Diffeomorphic Matching Problems in One Dimension: Designing and Minimizing Matching Functionals

Abstract: This paper focuses on matching 1D structures by variational methods. We provide rigorous rules for the construction of the cost function, on the basis of an analysis of properties which should be satisfied by the optimal matching. A new, exact, dynamic programming algorithm is then designed for the minimization. We conclude with experimental results on shape comparison.