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International audience; The Besicovitch pseudodistance defined in [1] for biinfinite sequences is invariant by translations. We generalize the definition to arbitrary locally compact second-countable groups and study how properties of the pseudodistance, including invariance by translations, are determined by those of the sequence of sets of finite positive measure used to define it. In particular, we restate from [2] that if the Besicovitch pseudodistance comes from an exhaustive Følner sequence, then every shift is an isometry. For non-Følner sequences, it is proved that some shifts are not isometries, and the Besicovitch pseudodistance with respect to some subsequences even makes them discontinuous.

The Copernicus Marine Environment Monitoring Service (CMEMS) is providing operational data products for the European Seas. During the current phase of CMEMS, Baltic Monitoring Forecasting Centre (BAL MFC) has been developing a brand new coupled forecasting system for the Baltic Sea area. With the latest update in December 2020 the products of the new model system for near real-time became operationally available in the CMEMS catalogue. The system consists of four parts – Nucleus for European Modelling of the Ocean (NEMO), Ecological Regional Ocean Model (ERGOM), the Wind Wave Model (WAM) and the Parallel Data Assimilation Framework (PDAF). The most notable difference between the new system and its predecessor is the change of the physical model to NEMO 4.0 instead of HBM (Hiromb Boos Model), resulting in an improvement in the representation of the physical parameters. NEMO 4 and ERGOM are one-way online coupled and runs at the same production unit. In addition, NEMO and WAM are offline coupled in both directions. These two models are produced at two different production units. WAM uses ice conditions and currents from NEMO to increase the quality of the wave forecast. In return WAM provides NEMO with stokes drift, mainly to improve the extreme sea level events. We present the components of the forecasting system focusing on the implementation and effects of the coupling., Le Copernicus Marine Environment Monitoring Service (CMEMS) fournit des produits de données opérationnelles pour les mers européennes. Au cours de la phase actuelle du CMEMS, le Centre de surveillance et de prévision de la Baltique (BAL MFC) a développé un tout nouveau système de prévision couplé pour la zone de la mer Baltique. Avec la dernière mise à jour de décembre 2020, les produits du nouveau système de modèles pour le temps quasi réel sont devenus disponibles de manière opérationnelle dans le catalogue CMEMS. Le système se compose de quatre parties - Nucleus for European Modelling of the Ocean (NEMO), Ecological Regional Ocean Model (ERGOM), le Wind Wave Model (WAM) et le Parallel Data Assimilation Framework (PDAF). La différence la plus notable entre le nouveau système et son prédécesseur est le passage du modèle physique à NEMO 4.0 au lieu de HBM (Hiromb Boos Model), ce qui entraîne une amélioration de la représentation des paramètres physiques. NEMO 4 et ERGOM sont couplés en ligne à sens unique et fonctionnent dans la même unité de production. En outre, NEMO et WAM sont couplés hors ligne dans les deux sens. Ces deux modèles sont produits dans deux unités de production différentes. WAM utilise les conditions de glace et les courants de NEMO pour améliorer la qualité de la prévision des vagues. En retour, WAM fournit à NEMO la dérive des stokes, principalement pour améliorer les événements extrêmes de niveau de la mer. Nous présentons les composants du système de prévision en nous concentrant sur la mise en œuvre et les effets du couplage.

International audience; The Besicovitch pseudodistance defined in [BFK99] for one-dimensional configurations is invariant by translations. We generalize the definition to arbitrary countable groups and study how properties of the pseudodistance, including invariance by translations, are determined by those of the sequence of finite sets used to define it. In particular, we recover that if the Besicovitch pseudodistance comes from a nondecreasing exhaustive Følner sequence, then every shift is an isometry. For non-Følner sequences we prove that some shifts are not isometries, and the Besicovitch pseudodistance with respect to some subsequence even makes them non-continuous.

The runup of initial Gaussian narrow-banded and wide-banded wave fields and its statistical characteristics are investigated using direct numerical simulations, based on the nonlinear shallow water equations. The bathymetry consists of the section of a constant depth, which is matched with the beach of constant slope. To address different levels of nonlinearity, the time series with five different significant wave heights are considered. The selected wave parameters allow also seeing the effects of wave breaking on wave statistics. The total physical time of each simulated time-series is 1000 hours (~360000 wave periods). The statistics of calculated wave runup heights are discussed with respect to the wave nonlinearity, wave breaking and the bandwidth of the incoming wave field. The conditional Weibull distribution is suggested as a model for the description of extreme runup heights and assessment of extreme inundations., 13 pages, 7 figures, 2 tables, 32 references. Other author's papers can be downloaded at http://www.denys-dutykh.com/

SciPy is an open source scientific computing library for the Python programming language. SciPy 1.0 was released in late 2017, about 16 years after the original version 0.1 release. SciPy has become a de facto standard for leveraging scientific algorithms in the Python programming language, with more than 600 unique code contributors, thousands of dependent packages, over 100,000 dependent repositories, and millions of downloads per year. This includes usage of SciPy in almost half of all machine learning projects on GitHub, and usage by high profile projects including LIGO gravitational wave analysis and creation of the first-ever image of a black hole (M87). The library includes functionality spanning clustering, Fourier transforms, integration, interpolation, file I/O, linear algebra, image processing, orthogonal distance regression, minimization algorithms, signal processing, sparse matrix handling, computational geometry, and statistics. In this work, we provide an overview of the capabilities and development practices of the SciPy library and highlight some recent technical developments., Comment: Article source data is available here: https://github.com/scipy/scipy-articles

6 pages, 1 figure, 2 tables, 11 references. Other author's papers can be downloaded at http://www.denys-dutykh.com/; International audience; Dispersive effects during long wave run-up on a plane beach are studied. We take an advantage of experimental data collection of different wave types (single pulses, sinusoidal waves, bi-harmonic waves, and frequency modulated wave trains) and simulate their run-up using two models: (i) non-dispersive nonlinear shallow water theory and (ii) dispersive Boussinesq type model based on the modified Peregrine system. It is shown, that for long positive pulses, dispersive effects are not so important and nonlinear shallow water theory can be used. However, for periodic sinusoidal and bi-harmonic pulses of the same period, the dispersive effects result in significant wave transformation during its propagation, but do not have a strong impact on its maximal run-up height. Overall, for maximum wave run-up height, we could not find a preference of dispersive model against the nondispersive one, and, therefore, suggest using nonlinear shallow water model for long wave run-up height estimation.

International audience; The purpose of this chapter is to present a survey on the effective algebraic analysis approach to linear systems theory with applications to control theory and mathematical physics. In particular, we show how the combination of effective methods of computer algebra -- based on Gröbner basis techniques over a class of noncommutative polynomial rings of functional operators called Ore algebras -- and constructive aspects of module theory and homological algebra enables the characterization of structural properties of linear functional systems. Algorithms are given and a dedicated implementation, called OreAlgebraicAnalysis, based on the Mathematica package HolonomicFunctions, is demonstrated.

21 pages, 5 figures, 1 table, 31 references. Other author's papers can be downloaded at http://www.denys-dutykh.com/; International audience; The description of gravity waves propagating on the water surface is considered from a historical point of view, with specific emphasis on the development of a theoretical framework and equations of motion for long waves in shallow water. This provides the foundation for a subsequent discussion about tsunami wave propagation and run-up on a sloping beach, and in particular the role of wave dispersion for this problem. Wave tank experiments show that wave dispersion can play a significant role for the propagation and wave transformation of wave signals that include some higher frequency components. However, the maximum run-up height is less sensitive to dispersive effects, suggesting that run-up height can be adequately calculated by use of non-dispersive model equations.

International audience; This paper is dedicated to the IEEE European Test Symposium (ETS). It offers an overview of all the European Test Workshop and Symposium events, from its first edition in 1996 to the next edition in 2020.

Evaluation of wave run-up characteristics is one of the most important tasks in coastal oceanography. This knowledge is required as for planning coastal structures and protection works, as for short-term tsunami forecast and tsunami warning. The nonlinear deformation and run-up of single tsunami waves of positive polarity in the conjoined water basin, which consists of the constant depth section and a plane beach is studied numerically and analytically in the framework of the nonlinear shallow water theory. Analytically, wave propagation along the constant depth section and its run-up on a beach are considered independently without taking into account wave reflection from the toe of the bottom slope. The propagation along the bottom of constant depth is described by Riemann wave, while the wave run-up on a plane beach is calculated using rigorous analytical solutions of the nonlinear shallow water theory following the Carrier-Greenspan approach. The numerical scheme employs the finite volume method and is based on the second order UNO2 reconstruction in space and the third order Runge-Kutta scheme with locally adaptive time steps. The model is validated against experimental data. Found analytically, that maximum run-up height of single waves of positive polarity on a beach of a conjoined water basin depends on the wave front steepness at the toe of the bottom slope. This dependence is general for single waves of different amplitudes and periods and can be approximated by the power fit: R max / R 0 = ( s / s 0 )^0.42. This dependence is slightly weaker than the corresponding dependence for a sine wave, proportional to the square root of the wave front steepness. The stronger dependence of a sinewave run-up on the wave front steepness is consistent with the philosophy of N-waves. Shown numerically, that all numerical curves for different wave amplitudes and periods, are parallel to the analytical one. Therefore, for estimates one can use the analytical dependence onthe wave front steepness., Voir le livre des résumés de cette conférence.

The estimate of individual wave run-up is especially important for tsunami warning and risk assessment as it allows to evaluate the inundation area. Here as a model of tsunami we use the long single wave of positive polarity. The period of such wave is rather long which makes it different from the famous Korteweg-de Vries soliton. This wave nonlinearly deforms during its propagation in the ocean, what results in a steep wave front formation. Situations, when waves approach the coast with a steep front are often observed during large tsunamis, e.g. 2004 Indian Ocean and 2011 15 Tohoku tsunamis. Here we study the nonlinear deformation and run-up of long single waves of positive polarity in the conjoined water basin, which consists of the constant depth section and a plane beach. The work is performed numerically and analytically in the framework of the nonlinear shallow water theory. Analytically, wave propagation along the constant depth section and its run-up on a beach are considered independently without taking into account wave interaction with the toe of the bottom slope. The propagation along the bottom of constant depth is described by Riemann wave, while the wave 20 run-up on a plane beach is calculated using rigorous analytical solutions of the nonlinear shallow water theory following the Carrier-Greenspan approach. Numerically, we use the finite volume method with the second order UNO2 reconstruction in space and the third order Runge-Kutta scheme with locally adaptive time steps. During wave propagation along the constant depth section, the wave becomes asymmetric with a steep wave front. Shown, that the maximum run-up height depends on the front steepness of the incoming wave approaching the toe of the bottom slope. The corresponding formula for maximum 25 run-up height, which takes into account the wave front steepness, is proposed., Comment: 17 pages, 11 figures, 43 references. Other author's papers can be downloaded at http://www.denys-dutykh.com/

International audience; The nonlinear realization theory is recasted for time-varying single-input single-output nonlinear systems. The concept of realization has been extended to cover also the realizations with order greater than the order of input–output equation. The minimal realization problem is studied. The state realization is said to be minimal if it is either accessible and observable or its state dimension is minimal. In the linear case the two definitions are equivalent, but not for nonlinear time-invariant systems. It is shown that the two definitions remain equivalent for nonlinear systems under certain technical assumptions. Two alternative methods are presented for finding the minimal realization.

International audience

International audience; Two sets of experiments in a wave flume to demonstrate resonance phenomena in laboratory conditions have been performed. The first set was performed to investigate nonlinear wave run-up on the beach. It is revealed that under certain wave excitation frequencies, a significant increase in run-up amplification is observed Ezersky et al. (Nonlin Processes Geophys 20:35, 2013, [1]). It is found that this amplification is due to the excitation of resonant mode in the region between the shoreline and wave maker. The second set of experiments was performed to model an excitation of localized mode (edge waves) by breaking waves propagating towards shoreline. It is shown that the excitation of edge waves is due to parametric instability similar to pendulum with vibrating point of suspension. The domain of instability in the plane of parameters (amplitude—frequency) of surface wave is found. It was found that for amplitude of surface wave slightly exceeding the threshold, the amplitude of edge wave grows exponentially with time, whereas for the large amplitude, the wave breaking appears and excitation of edge wave does not occur. It was shown that parametric excitation of edge wave can increase significantly (up to two times) the maximal run-up height.

International audience; An algebraic framework for discrete-time nonlinear control systems is introduced, based on the forward and backward shifts of the vector fields. It appears to be the dual of the framework based on the differential 1-forms. As applications, the characterization of accessibility and the solution to the static state feedback linearization problem are stated in terms of the given vector fields.

International audience; Immune cells express powerful and harmful effectors that require tight regulation. Heterotrimeric G proteins are critical mediators in translating extracellular signals into cell responses, which need a fine-tuned regulation for the control of cell activation. Regulator of G-protein signalling 16 (RGS16) has been identified as a key factor of G protein-mediated activation in lymphocytes, modulating inflammatory and survival responses of various cell types. However, data about the expression of this regulatory protein in monocytes are scarce, and it has remained unclear whether activation and migration of these cells are regulated by RGS16. In this study, the impact of RGS16 on the production of inflammatory cytokines by activated human monocytes was investigated in vitro using the human promonocytic cell line THP-1 as a model. Gain and loss of function experiments showed that RGS16 overexpression reduces the expression of pro-inflammatory cytokines IL-1β, IL-6, IL-8 and TNFα, while RGS16 knockdown by RNAi upregulates IL-1β, IL-6 and TNFα but not IL-8. RGS16 knockdown was also shown to enhance Pam3-mediated induction of the anti-inflammatory cytokine IL-10. Our results indicate that RGS16 restricts the activation-induced pro-inflammatory profile in myeloid cells.

The paper addresses the disturbance decoupling problem for MIMO discrete-time nonlinear systems. A sufficient conditions are derived to solve the problem by dynamic measurement feedback, i.e. the feedback that depends on measurable outputs only. The solution to the disturbance decoupling problem, described in this paper, is based on the input-output linearization, which is used to linearize certain functions. Two examples are added to illustrate the results.

International audience; Integrity – because of its connection with ethics – has always been of interest to both moral philosophy and the world’s wisdom traditions. Throughout the history of ethical philosophy there has been an emphasis on the concept of integrity in terms of its relationship to character development and morality. However, there is also a relationship between integrity, well-being, and what it means to be well-integrated within the fabric of existence—which was especially evident in Aristotle’s Virtue Ethics. Aristotle’s explanation of integral being is also important to understanding the connection between individual and social flourishing and the having appropriate interactions both with nature and with the primordial forces of existence.This article argues that the term integrity has aspects that are broader than merely referring to human character traits. Integrity, because it enhances a person’s interactions in ways that enable an individual to flourish and enjoy an enhanced quality of life is connected with being ellintegrated within the fabric of Being. The basic premise of this article is that integrity is promoted by religion, philosophy, neurobiology, and social psychology with the intention of helping the individual realize a desired state. This desired state, in terms of Aristotle’s moral philosophy, is tantamount to realizing one’s highest good or helping a person to achieve his or her most desired outcome.

International audience; The state realization is called minimal if it is either accessible and observable or its state dimension is minimal. In the linear case those two de nitions are equivalent, but not for nonlinear time-invariant systems. It is shown that de nitions remain equivalent in case one is searching for minimal realization in a larger class of nonlinear time-varying systems.First, nonlinear realization theory is recasted for time-varying nonlinear systems. A necessary and sufficient realizability condition is given in terms of integrability of certain subspace. The mathematical tools used for this purpose are the algebraic approach of di erential forms and the theory of the skew polynomial rings; these tools are again extended from time-invariant to time-varying systems.

The purpose of this paper is to present a survey on the effective algebraic analysis approach to linear systems theory with applications to control theory and mathematical physics. In particular, we show how the combination of effective methods of computer algebra - based on Gröbner basis techniques over a class of noncommutative polynomial rings of functional operators called Ore algebras - and constructive aspects of module theory and homological algebra enables the characterization of structural properties of linear functional systems. Algorithms are given and a dedicated implementation, called OreAlgebraicAnalysis, based on the Mathematica package HolonomicFunctions, is demonstrated.; Le but de ce papier est de présenter un état de l’art d’une approche par l’analyse algébrique effective de la théorie des systèmes linéaires avec des applications à la théorie du contrôle et à la physique mathématique.En particulier, nous montrons comment la combinaison des méthodes effectives de calcul formel - basées sur lestechniques de bases de Gröbner sur une classe d’algèbres polynomiales noncommutatives d’opérateurs fonctionnels appelée algèbres de Ore - et d’aspects constructifs de théorie des modules et d’algèbre homologique permet lacaractérisation de propriétés structurelles des systèmes linéaires fonctionnels. Des algorithmes sont donnés et uneimplémentation dédiée, appelée OREALGEBRAICANALYSIS, basée sur le package Mathematica HOLONOMIC-FUNCTIONS, est présentée

The contributions of autonomous underwater gliders as an observing platform in the in-situ global ocean observing system (GOOS) are investigated. The assessment is done in two ways: First, the existing in-situ observing platforms contributing to GOOS (floats, surface drifters, moorings, research/commercial ships) are characterized in terms of their current capabilities in sampling key physical and bio-geochemical oceanic processes. Next the gliders’ capabilities are evaluated in the context of key applications. This includes an evaluation of 140 references presented in the peer-reviewed literature. It is found that GOOS has adequate coverage of sampling in the open ocean for several physical processes. There is a lack of data in the present GOOS in the transition regions between the open ocean and shelf seas. However, most of the documented scientific glider applications operate in this region, suggesting that a sustained glider component in the GOOS could fill that gap. Glider data are included for routine product generation (e.g. alerts, maps). Other noteworthy process-oriented applications where gliders are important survey tools include local sampling of the (sub)mesoscale, sampling in shallow coastal areas, measurements in hazardous environments, and operational monitoring. In most cases, the glider studies address investigations and monitoring of processes across multiple disciplines, making use of the ease to implement a wide range of sensors to gliders. The maturity of glider operations, the wide range of applications that map onto growing GOOS regional needs, and the maturity of glider data flow all justify the formal implementation of gliders into the GOOS. Remaining challenges include the execution of coordinated multinational missions in a sustained mode as well as considering capacity-building aspects in glider operations as well as glider data use., Comments from two anonymous reviewers and the Associate Editor G. Griffiths are appreciated. This work was supported by the European Union 7th Framework Programme (FP7 2007–2013), under grant agreement number 284321 GROOM (www.groom-fp7.eu); and the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement number 633211 AtlantOS.

International audience; In this paper the notion of integrability is defined for 1-forms defined in the time–delay context. While in the delay-free case, a set of 1-forms defines a vector space, it is shown that 1-forms computed for time-delay systems have to be viewed as elements of a module over a certain non-commutative polynomial ring. Two notions of integrability are defined, strong and weak integrability, which coincide in the delay-free case. Necessary and sufficient conditions are given to check if a set of 1-forms is strongly or weakly integrable. To show the importance of the topic, integrability of 1-forms is used to characterize the accessibility property for nonlinear time-delay systems. The possibility of transforming a system into a certain normal form is also considered.

International audience; Whether an autonomous system can be rendered fully accessible through one single actuator is a long-standing open problem, which got some solutions in special cases when additional constraints are considered. Herein, it is shown that a solution to the general problem is provided as an easy consequence of the straightening theorem. This solution is innovative for linear time-invariant systems as well and relaxes the well-known cyclicity condition as it involves nonlinear state transformations. The dual problem of designing one single sensor to render a given system observable obtains a similar almost unconditional solution.

International audience; A necessary and sufficient condition is derived for the solvability of the disturbance decoupling problem by pure shift dynamic compensator. It corrects previously obtained results for multi-input multi-output (MIMO) systems.Also, necessary and sufficient conditions are given for the solvability of the problem by dynamic compensator for SISO systems.

International audience; Reflection and transmission of elastic waves at the interface between two distinct micromorphic media are considered in the one-dimensional setting. Dual internal variable approach is used for the description of the microstructure influence on the global motion. It is shown that reflection and transition coefficients for plane waves depend on the coupling between macro-and micro-motions as well as on the choice of the microstructural interaction at the interface. Numerical simulations exhibiting results with promising technological implications are shown.

International audience; In this paper the integrability of differential one-forms is studied in case of timedelays are present. Two notions, weak and strong integrability, are defined and the difference with delay-free case is explained. After giving the algorithms to check if some one-forms are strongly or weakly integrable, based on examples, the differences of the two notions of integrability are being studied. Finally, the role of integrability is explained when looking for a change of coordinates.

International audience; This paper describes the mathematical models derived for wave propagation in solids with internal structure. The focus of the overview is on one-dimensional models which enlarge the classical wave equation by higher-order terms. The crucial parameter in models is the ratio of characteristic lengths of the excitation and the internal structure. Novel approaches based on the concept of internal variables permit one to take the thermodynamical conditions into account directly. Examples of generalisations include frequency-dependent multiscale models, nonlinear models and thermoelasticity. The substructural complexity within the framework of elasticity gives rise to dispersion of waves. Dispersion analysis shows that acoustic and optical branches of dispersion curves together describe properly wave phenomena in microstructured solids. In the case of nonlinear models, the governing equations are of the Boussinesq type. It is argued that such models of waves in solids with microstructure display properties that can be analysed as phenomena of complexity.

International audience; This paper addresses the input-output decoupling problem for discrete-time nonlinear systems by measurement feedback. Necessary and sufficient conditions are given to solve the problem by static or dynamic measurement feedback, respectively. Since the dynamic measurement solution presented here depends on the solution of the input-output linearization problem, a sufficient condition for linearizability of certain functions is also given. Finally, the derived conditions are specified to solve the problem by output feedback.

International audience; Four Holocene-long East Antarctic deuterium excess records are used to study past changes of the hydrological cycle in the Southern Hemisphere. We combine simple and complex isotopic models to quantify the relationships between Antarctic deuterium excess fluctuations and the sea surface temperature (SST) integrated over the moisture source areas for Antarctic snow. The common deuterium excess increasing trend during the first half of the Holocene is therefore interpreted in terms of a warming of the average ocean moisture source regions over this time. Available Southern Hemisphere SST records exhibit opposite trends at low latitudes (warming) and at high latitudes (cooling) during the Holocene. The agreement between the Antarctic deuterium excess and low-latitude SST trends supports the idea that the tropics dominate in providing moisture for Antarctic precipitation. The opposite trends in SSTs at low and high latitudes can potentially be explained by the decreasing obliquity during the Holocene inducing opposite trends in the local mean annual insolation between low and high latitudes. It also implies an increased latitudinal insolation gradient that in turn can maintain a stronger atmospheric circulation transporting more tropical moisture to Antarctica. This mechanism is supported by results from a mid-Holocene climate simulation performed using a coupled ocean-atmosphere model.

International audience; This chapter addresses how agent organisations can improve and accelerate coordination processes in open environments. A state-of-art of recent proposals for describing agent organisations is given, relating the different methodologies and formal approaches for defining agent organisations in an explicit way. As example, four different proposals developed within the COST action IC0801 are detailed: (i) the MOISE organisation Model, which provides structural, functional and normative specifications of an organisation, and it is integrated in an Organisation Management infrastructure; (ii) the Virtual Organisation Model, which describes the structural, functional, dynamical, environmental and normative dimensions of an organisation, and it is complemented by the Virtual Organisation Formalization; (iii) the Agent-Oriented Modelling for sociotechnical systems, which are organisations consisting of human and man-made agents; and (iv) the AAOL agent architecture, in which groups of autonomous agents are organized in Localities. This chapter proposes a global comparison of different existing organisational models with the four detailed models in terms of the different description dimensions they propose.

The notion of Multi-Agent System environment is currently considered as a mediating entity, functioning as enabler but possibly also as a manager and constrainer of agent actions, perceptions, and interactions. In this paper, we analyze how the environment could be a first class abstraction to support the building, the development and the management of Agreements in decentralized and open systems between autonomous agents. To this aim we analyze the synergies between the environment and the foundational dimensions of agreement technologies such as semantics, norms, organizations, argumentation & negotiation, trust.

International audience; An algebraic framework for discrete-time nonlinear control systems is introduced, based on the forward and backward shifts of the vector fields, dual to that based on differential 1-forms. As an application, the accessibility criterion of a control system in terms of vector fields is given and compared to those obtained under more restrictive assumptions.

International audience; This paper deals with average prosodic characteristics of Estonian as observed in 25 hours of manually transcribed spontaneous speech. The proposed investigations address the prosodic realisations on a lexical basis, as one of the goals is to make use of these characteristics within the lexical decision process of automatic speech recognition systems. As a first step, the speech corpus was split into word categories according to lexical frequency (most frequent vs. less frequent words), syllabic word length and gender. Average prosodic profiles were computed with respect to fundamental frequency, segment duration and intensity. Statistical analyses confirm a word-initial syllable stress with high average f 0 and intensity values, which then progressively decrease towards word-final syllables. Prosodic profiles also reveal that the longer the words, the higher these word-initial stress values are. Whereas f 0 and intensity profiles show very similar profiles across word categories, duration profiles reveal less regular patters. For the frequent word category, a rising duration can be observed from the first to final vowels, whilst the other words show longer duration in monosyllabic words and in final vowels of 4-syllabic words. Overall, our results suggest that prosodic cues could contribute to word boundary location in continuous speech.

International audience; We systematically derive a classical call-by-need sequent calculus, which does not require an unbounded search for the standard redex, by using the unity of semantic artifacts proposed by Danvy et al. The calculus serves as an intermediate step toward the generation of an environment-based abstract machine. The resulting abstract machine is context-free, so that each step is parametric in all but one component. The context-free machine elegantly leads to an environment-based CPS transformation. This transformation is observationally different from a natural classical extension of the transformation of Okasaki et al., due to duplication of un-evaluated bindings.

International audience; In this paper, the model matching problem of nonlinear single-input single-output discrete-time systems is considered. Both feedforward and feedback solutions are given. The problem is studied within the transfer function approach in which the system is described by the quotient of two polynomials from the non-commutative ring of skew polynomials. In general, the feedforward solution does not always exist, therefore the subclass of nonlinear control systems is specified for which the solution exists. The feedback solution exists always. Additionally, the conditions for the existence of the proper compensator are provided. The developed theory and algorithm are illustrated of several examples.

International audience; Informal proceedings of the 7th workshop on Fixed Points in Computer Science (FICS 2010), held in Brno, 21-22 August 2010

Information about freak wave events in the ocean reported by mass media and derived from personal observations in 2005 is collected and analysed. Nine cases are selected as true freak wave events from a total number of 27 mentioned. Besides rogue waves in the open sea, the problem of freak wave events on the shore is emphasized. These accidents are related to unexpected wave impact upon the coast and shore constructions or to sudden intensive flooding of the coast. Of the nine events considered reliable here, three events correspond to open-sea cases, while the six others occurred nearshore.

International audience; A method for the in situ measurement of the kinetics of ATP metabolic transformation using capillary electrophoresis (CE) has been developed. The depletion of ATP and formation of ADP were monitored in situ by using saponin-permeabilized muscle fibers. The method of micellar electrokinetic chromatography, employing reversed electroosmotic flow by cationic surfactant and reversed-polarity mode, provided an efficient and reproducible separation of nucleotides and enabled kinetic analysis of the reaction to be performed in a large range of nucleotide concentrations that approaches physiological concentrations of ATP in the muscle cells, without the need for precipitation of proteins prior to sample application. The analytes were detected at a nM level with a reproducibility of about 7%. This reproducibility enabled the comparison of different competing kinetic models of ATP conversion to ADP and the results show that the MgATPase activity in the fast-twitch gastrocnemius muscle followed biphasic kinetics that corresponds to the allosteric character of regulation of the enzyme(s) activity at physiological ATP concentrations. The results also confirmed that the combination of minimal sample volume requirements, rapid measurement and reproducibility makes the micellar CE a valuable tool for the analysis of biological fluids and understanding the processes of biological interest.

International audience; Recent studies have revealed the structural and functional interactions between mitochondria, myofibrils and sarcoplasmic reticulum in cardiac cells. Direct channeling of adenosine phosphates between organelles identified in the experiments indicates that diffusion of adenosine phosphates is limited in cardiac cells due to very specific intracellular structural organization. However, the mode of diffusion restrictions and nature of the intracellular structures in creating the diffusion barriers is still unclear, and, therefore, a subject of active research. The aim of this work is to analyze the possible role of two principally different modes of restriction distribution for adenosine phosphates (a) the uniform diffusion restriction and (b) the localized diffusion limitation in the vicinity of mitochondria, by fitting the experimental data with the mathematical model. The reaction-diffusion model of compartmentalized energy transfer was used to analyze the data obtained from the experiments with the skinned muscle fibers, which described the following processes: mitochondrial respiration rate dependency on exogenous ADP and ATP concentrations; inhibition of endogenous ADP-stimulated respiration by pyruvate kinase (PK) and phosphoenolpyruvate (PEP) system; kinetics of oxygen consumption stabilization after addition of 2 mM MgATP or MgADP; ATPase activity with inhibited mitochondrial respiration; and buildup of MgADP concentration in the medium after addition of MgATP. The analysis revealed that only the second mechanism considered--localization of diffusion restrictions--is able to account for the experimental data. In the case of uniform diffusion restrictions, the model solution was in agreement only with two measurements: the respiration rate as a function of ADP or ATP concentrations and inhibition of respiration by PK + PEP. It was concluded that intracellular diffusion restrictions for adenosine phosphates are not distributed uniformly, but rather are localized in certain compartments of the cardiac cells.

International audience; The paper addresses the problem of speeding up functional cycle-based simulation of digital systems. The system is represented as a network of interconnected Decision Diagrams (DD). Three new innovative simulatioan algorithms are introduced to implement the idea of simulation execution according to activities of the system variables : forward event-driven algorithm and two versions of back-racing algorithms. Experiments are presented to show the simulation efficiency improvement offered by those algorithms.

International audience; The aim of this thesis is to investigate the link between biochemical intracellular processes and mechanical contraction of the cardiac muscle. First, the regulation of intracellular energy fluxes between mitochondria and myofibrils is studied. It is shown, that the experimentally observed metabolic stability of the cardiac muscle is reproducible by a simple feedback regulation mechanism, i.e., ATP consumption in myofibrils and ATP production in mitochondria are balanced by the changes of the high energy phosphate concentrations. Second, an important property of energy transformation from biochemical form to mechanical work in the cardiac muscle, the linear relationship between the oxygen consumption and the stress-strain area, is replicated by a cross-bridge model. Third, by using the developed cross-bridge model, the correlation between ejection fraction of the left ventricle and heterogeneity of sarcomere strain, developed stress and ATP consumption in the left ventricular wall is established. Fourth, an experimentally observed linear relationship between oxygen consumption and the pressure-volume area can be predicted theoretically from a linear relationship between the oxygen consumption and the stress-strain area. Summing up, it is shown how the macrovariables of a cardiac muscle are interwoven with intracellular physiological processes into a whole.

International audience; A modification of the wave-propagation algorithm is used as a tool for determining contact quantities in a finite-volume scheme for the numerical simulation of two-dimensional thermoelastic wave propagation in inhomogeneous media. The modification is needed to provide the satisfaction of the thermodynamic consistency conditions between adjacent elements. It appears that the algorithm is thermodynamically consistent except for the limiter functions. Therefore, a composite scheme is used where the Godunov step is applied after each three second-order Lax–Wendroff steps. Elimination of source terms is made following the method of balancing source terms after independent solution of the heat conduction equation.

International audience; Decision diagrams (DD) present a suitable way for the digital system representation efficiently used in several steps of the entire design cycle : design verification, testing, test pattern generation and fault simulation. This paper presents some ways to optimize the decision diagram representation aimed at improving simulation efficiency. Two new types of diagrams are introduced : vector decision diagrams (VDDs) and compressed VDDs, as an efficient and concise model of the system behavior, which preserves all the advantes of the decision diagrams. In order to fully exploit the advantages of DDs new simulatioan algorithms based on cycle-based forward event-driven and recursive back-tracing techniques are proposed. The experimental results of the comparison of different types of DDs as well as of different simulation algorithms on DDs are included.

International audience; The paper addresses the problem of the cycle-based simulation performance of synchronous digital systems modeled by the High Level Decision Diagrams (DDs). A new class of DD representation, called Register-Oriented DDs (RODD) is introduced. RODD model appears to be an efficient and compact representation of the system behavior for the high-level cycle simulation. In order to fully exploit the advantages of RODDs a new simulation algorithm, which is a combination of cycle-based forward event-driven and recursive back-tracing techniques is proposed. The charecteristics of the simulatioan algorithms used to efficiently execute the evaluation of DD network are discussed. Further the experimental results carried out on the real case examples demonstrating the gain in simulation performance of the proposed approach and a comparison of four cycle-based simulation algorithms are presented. Additionally, a comparison with the commercial event-driven and cycle-based HDL simulation tools is included.

International audience; Decision diagrams (DD) present a suitable way for the digital system representation efficiently used in several steps of the entire design cycle : for design verification, test generation and fault simulation. They offer a competitive simulation performance in comparison to the event-driven HDL-based simulation ; however, their initial complexity does not allow to favorably compare their performance with the algorithmic functional description of the circuit's behavior. This article presents the optimization of the DD representation aimed at improving their simulation efficiency. Two types of DDs are introduced : vector decision diagrams (VDDs) and compressed VDDs as an efficient and concise model of system behavior, which preserves all the advantages of the decision diagrams. Their computational complexity is similar to the algorithmic description. The results of the comparisons between the different types of DDs and the algorithmic representation are included. This comparison is based on the symbolic complexity measure, defined for that purpose.

International audience; This paper addresses the problem of efficient functional simulation of synchronous digital systems. A technique based on the use of Decision Diagrams (DD) for representing the functions of a design at RT and behavioural level is introduced. The DD evaluation technique is combined with cycle based simulation mechanism to achieve the significant speed up of the simulation execution. Experimental results are provided for demonstrating the efficiency gain of this method in comparison to the event-driven simulation.