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Takagi-Sugeno fuzzy logic applied to a photovoltaic system for power maximization
No full textInternational audienc
A multi-scale, multi-paradigm epidemiological modelling language for investigating Q Fever regional infection dynamics
No full textInternational audienceThe regional spread of Q fever, an endemic cat- tle zoonosis, relies upon airborne transmission and between-herd trade movements. Our goal was to be er understand the contribution of each pathway to yearly herd incidence by coupling within- and between-herd dynamics.To accelerate model design, explore multiple as- sumptions at each scale with a reduced amount of code to write, and enhance reliability, reusabil- ity and reproducibility, we used a generic frame- work, EMuLsion, which provides a domain-speci c language (DSL) for explicitly describing all compo- nents of epidemiological models, and relies upon a multi-level agent-based architecture to encompass existing modelling paradigms
Analysis of Skeletal Shape Trajectories for Person Re-Identification
No full textInternational audienceIn this paper, we are interested in people re-identification using skeleton information provided by a consumer RGB-D sensor. We perform the modelling and the analysis of human motion by focusing on 3D human joints given by skeletons. In fact, the motion dynamic is modeled by projecting skeleton information on Grassmann manifold. Moreover, in order to define the identity of a test trajectory, we compare it against a labeled trajectory database while using an unsupervised similarity assessment procedure. Indeed, the main contribution of this work resides in the introduced distance that combines temporal information as well as global and local geometrical ones. Realized experiments on standard datasets prove that the proposed method performs accurately even though it does not assume any prior knowledge
Estimation of Real Valued Impulse Responses based on Noisy Magnitude and Phase Measurements
No full textInternational audienc
A Multi-criteria Optimization Approach to Health Care Tasks Scheduling Under Resources Constraints
No full textInternational audienceWe are interested in this paper in studying and developing a decision support tool for multi-skill health care tasks scheduling in the Pediatric Emergency Department. We use an evolutionary algorithm and we propose the use of fuzzy logic to formulate an adapted fitness function. We consider the potential performance of the system and we set up a set of lower bounds characterizing criteria limits allowing to calculate the minimum waiting time for incoming patients and the corresponding latest ending time
Polyoxometalate, Cationic Cluster, and γ-Cyclodextrin: From Primary Interactions to Supramolecular Hybrid Materials
No full textInternational audienceHerein, we report on a three-component supramolecular hybrid system built from specific recognition processes involving a Dawson-type polyoxometalate (POM), [PWO], a cationic electron-rich cluster [TaBr(HO)], and γ-cyclodextrin (γ-CD). Such materials have been investigated using a bottom-up approach by studying the specific interactions between γ-CD and both types of inorganic units. Their ability to interact has been investigated in the solid state by single-crystal X-ray diffraction (XRD) and in solution using multinuclear NMR methods (including DOSY, EXSY, and COSY), electrospray ionization mass and UV-vis spectroscopies, electrochemistry, and isothermal titration calorimetry experiments. Single-crystal XRD analysis reveals that POM:γ-CD constitutes a highly versatile system which gives aggregates with 1:1, 1:2, and 1:3 stoichiometry. Surprisingly, these arrangements exhibit a common feature wherein the γ-CD moiety interacts with the Dawson-type POMs through its primary face. We present also the first structural model involving an octahedral-type metallic cluster with γ-CD. XRD study reveals that the cationic [TaBr(HO)] ion is closely embedded within two γ-CD units to give a supramolecular ditopic cation, suitable to be used as a linker within extended structure. Solution study demonstrates clearly that pre-associations exist in solution, for which binding constants and thermodynamic parameters have been determined, giving preliminary arguments about the chaotropic nature of the inorganic ions. Finally, both building blocks, i.e., the ditopic supramolecular cation {[TaBr(HO)]@2CD} and the Dawson-type anion, react together to give a three-component, well-ordered hybrid material derived either as a supramolecular hydrogel or single crystals. The solid-state structure shows an unprecedented helicoidal tubular chain resulting from the periodic alternation of POM and supramolecular cation, featuring short hydrogen-bonding contacts between the electron-poor POM and electron-rich cluster. The 1D tubular ionic polymer observed in the single crystals should make it possible to understand the long-range ordering observed within the hydrogel hybrid material. The supramolecular chemical complementarities between the γ-CD-based ditopic cation and POM open a wide scope for the design of hybrid materials that accumulate synergistic functionalities
Deductive Verification of a Hypervisor Model
No full text(27 pages)We propose a deductive-verification approach for proving partial-correctness and invariance properties on arbitrary transition systems, and demonstrate it on a security hypervisor model for machine code. Regarding partial correctness, we generalise the recently-introduced formalism of Reachability Logic, currently used as a language-parametric program logic, to arbitrary transition systems. We propose a sound and relatively-complete proof system for the resulting logic. The soundness of the proof system is formally established in the Coq proof assistant, and the mechanised proof provides us with a generic Reachability-Logic prover within Coq for transition-system specifications. The relative completeness of the proof system, although theoretical in nature, also has a practical value, as it induces a proof strategy that is guaranteed to prove all valid formulas on a given transition system. The strategy reduces partial-correctness verification to invariant verification; for the latter we propose an incremental technique in order to deal with the case-explosion problem. All these various techniques were instrumental in enabling us to deal with a nontrivial case study: proving that a Coq model of a security hypervisor meets its expected requirements, expressed as invariants and partial-correctness properties, within reasonable time and effort limits. We also report on some experiments with a C+ARM assembly implementation of our hypervisor in order to confirm the fact that it introduces a limited amount of execution-time overhead to operating-system calls
Energy-efficient scheduling for moldable real-time tasks on heterogeneous computing platforms
No full textInternational audienceIn this paper, we address the problem of executing (soft) real-time data processing applications on heterogeneous computing platforms with the goal of reducing the energy consumption. The typical application domain is edge computing (or fog computing), where a certain amount of data, collected from the environment, needs to be pre-processed in real-time before being sent to the central server for storage and final processing. The kind of applications we address here can be easily parallelized, and we also need to reduce as much as possible the necessary energy to perform such tasks. Heterogeneous Multi-core Processors (HMP) such as ARM big.LITTLE are designed to combine both performances and energy efficiency, so they are one of the preferred choices for this kind of applications. Here we focus on Dynamic Voltage and Frequency Scaling (DVFS), parallelization, real-time scheduling and resource allocation techniques. In the first part of the paper, we present a model of the performance and energy consumption of a parallel real-time task executed on an ARM bigLITTLE architecture. We use this model in the second part of the paper where we first define the optimization problem as an Integer Non-linear Programming (INLP) problem, and then propose heuristics for efficiently solving it. Finally, we present a wide range of synthetic experiments that demonstrate the performance of our approach