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Overdamped stochastic thermodynamics with multiple reservoirs ; Esposito, Massimiliano in Physical Review. E : Statistical, Nonlinear, and Soft Matter Physics (2016), 94(062148), After establishing stochastic thermodynamics for underdamped Langevin systems in contact with multiple reservoirs, we derive its overdamped limit using timescale separation techniques. The overdamped ... [more ▼] After establishing stochastic thermodynamics for underdamped Langevin systems in contact with multiple reservoirs, we derive its overdamped limit using timescale separation techniques. The overdamped theory is different from the naive theory that one obtains when starting from overdamped Langevin or Fokker-Planck dynamics and only coincides with it in the presence of a single reservoir. The reason is that the coarse-grained fast momentum dynamics reaches a nonequilibrium state, which conducts heat in the presence of multiple reservoirs. The underdamped and overdamped theory are both shown to satisfy fundamental fluctuation theorems. Their predictions for the heat statistics are derived analytically for a Brownian particle on a ring in contact with two reservoirs and subjected to a nonconservative force and are shown to coincide in the long-time limit. [less ▲] Detailed reference viewed: 14 (1 UL)Klaslokalen Binnenstebuiten: Leerkrachten over de veranderende onderwijsleeromgeving doorheen hun carrière (1960-2015) Herman, Frederik ; Article for general public (2016) Welke scholen hebben we nodig voor de 21ste eeuw? Hoe moeten die toekomstige schoolgebouwen eruitzien? Misschien wel als één grote open werkruimte – met zithoeken, labo’s, vergaderlokalen voor groepswerk ... [more ▼] Welke scholen hebben we nodig voor de 21ste eeuw? Hoe moeten die toekomstige schoolgebouwen eruitzien? Misschien wel als één grote open werkruimte – met zithoeken, labo’s, vergaderlokalen voor groepswerk, een immer toegankelijke media- en bibliotheek, enzovoort – waarin leerkrachten en leerlingen vrij kunnen bewegen naar gelang de activiteiten en noden. Zullen de ‘traditionele’ klaslokalen hun bestaansredenen verliezen in deze nieuwe onderwijsleeromgevingen? Het vraagstuk naar innovatieve scholenbouw is verre van nieuw. Inderdaad, eb en vloed kenmerken onze onderwijsgeschiedenis.klaslokalen hun bestaansredenen verliezen in deze nieuwe onderwijsleeromgevingen? Het vraagstuk naar innovatieve scholenbouw is verre van nieuw. Inderdaad, eb en vloed kenmerken onze onderwijsgeschiedenis. [less ▲] Detailed reference viewed: 17 (5 UL)Optimum stochastic modeling for GNSS tropospheric delay estimation in real-time ; Teferle, Felix Norman ; et al in GPS Solutions (2016) In GNSS data processing, the station height, receiver clock and tropospheric delay (ZTD) are highly correlated to each other. Although the zenith hydrostatic delay of the troposphere can be provided with ... [more ▼] In GNSS data processing, the station height, receiver clock and tropospheric delay (ZTD) are highly correlated to each other. Although the zenith hydrostatic delay of the troposphere can be provided with sufficient accuracy, zenith wet delay (ZWD) has to be estimated, which is usually done in a random walk process. Since ZWD temporal variation depends on the water vapor content in the atmosphere, it seems to be reasonable that ZWD constraints in GNSS processing should be geographically and/or time dependent. We propose to take benefit from numerical weather prediction models to define optimum random walk process noise. In the first approach, we used archived VMF1-G data to calculate a grid of yearly and monthly means of the difference of ZWD between two consecutive epochs divided by the root square of the time lapsed, which can be considered as a random walk process noise. Alternatively, we used the Global Forecast System model from National Centres for Environmental Prediction to calculate random walk process noise dynamically in real-time. We performed two representative experimental campaigns with 20 globally distributed International GNSS Service (IGS) stations and compared real-time ZTD estimates with the official ZTD product from the IGS. With both our approaches, we obtained an improvement of up to 10% in accuracy of the ZTD estimates compared to any uniformly fixed random walk process noise applied for all stations. [less ▲] Detailed reference viewed: 23 (1 UL)Nonequilibrium Thermodynamics of Chemical Reaction Networks: Wisdom from Stochastic Thermodynamics Rao, Riccardo ; Esposito, Massimiliano in Physical Review X (2016), 6(4), 041064 We build a rigorous nonequilibrium thermodynamic description for open chemical reaction networks of elementary reactions. Their dynamics is described by deterministic rate equations with mass action ... [more ▼] We build a rigorous nonequilibrium thermodynamic description for open chemical reaction networks of elementary reactions. Their dynamics is described by deterministic rate equations with mass action kinetics. Our most general framework considers open networks driven by time-dependent chemostats. The energy and entropy balances are established and a nonequilibrium Gibbs free energy is introduced. The difference between this latter and its equilibrium form represents the minimal work done by the chemostats to bring the network to its nonequilibrium state. It is minimized in nondriven detailed-balanced networks (i.e., networks that relax to equilibrium states) and has an interesting information-theoretic interpretation. We further show that the entropy production of complex-balanced networks (i.e., networks that relax to special kinds of nonequilibrium steady states) splits into two non-negative contributions: one characterizing the dissipation of the nonequilibrium steady state and the other the transients due to relaxation and driving. Our theory lays the path to study time-dependent energy and information transduction in biochemical networks. [less ▲] Detailed reference viewed: 33 (8 UL)Il nuovo pilastro europeo per i diritti sociali: insidie e opportunità Ratti, Luca Presentation (2016, December 20) Detailed reference viewed: 14 (0 UL)First-principles modeling of molecular crystals: structures and stabilities, temperature and pressure Hoja, Johannes ; ; Tkatchenko, Alexandre in Wiley Interdisciplinary Reviews: Computational Molecular Science (2016) The understanding of the structure, stability, and response properties of molecular crystals at finite temperature and pressure is crucial for the field of crystal engineering and their application. For a ... [more ▼] The understanding of the structure, stability, and response properties of molecular crystals at finite temperature and pressure is crucial for the field of crystal engineering and their application. For a long time, the field of crystal-structure prediction and modeling of molecular crystals has been dominated by classical mechanistic force-field methods. However, due to increasing computational power and the development of more sophisticated quantum-mechanical approximations, first-principles approaches based on density functional theory can now be applied to practically relevant molecular crystals. The broad transferability of first-principles methods is especially imperative for polymorphic molecular crystals. This review highlights the current status of modeling molecular crystals from first principles. We give an overview of current state-of-the-art approaches and discuss in detail the main challenges and necessary approximations. So far, the main focus in this field has been on calculating stabilities and structures without considering thermal contributions. We discuss techniques that allow one to include thermal effects at a first-principles level in the harmonic or quasi-harmonic approximation, and that are already applicable to realistic systems, or will be in the near future. Furthermore, this review also discusses how to calculate vibrational and elastic properties. Finally, we present a perspective on future uses of first-principles calculations for modeling molecular crystals and summarize the many remaining challenges in this field. [less ▲] Detailed reference viewed: 47 (4 UL)Single station Monitoring of Volcanoes Using Seismic ambient noise De Plaen, Raphaël ; ; et al Poster (2016, December 16) Detailed reference viewed: 16 (2 UL)On horizontal and vertical categorifications of Leibniz algebras Poncin, Norbert Presentation (2016, December 16) Detailed reference viewed: 12 (1 UL)Images of Galois representations and p-adic models of Shimura curves Amoros Carafi, Laia Doctoral thesis (2016) The thesis treats two questions situated in the Langlands program, which is one of the most active and important areas in current number theory and arithmetic geometry. The first question concerns the ... [more ▼] The thesis treats two questions situated in the Langlands program, which is one of the most active and important areas in current number theory and arithmetic geometry. The first question concerns the study of images of Galois representations into Hecke algebras coming from modular forms over finite fields, and the second one deals with p-adic models of Shimura curves and its bad reduction. Consequently, the thesis is divided in two parts. The first part is concerned with the study of images of Galois representations that take values in Hecke algebras of modular forms over finite fields. The main result of this part is a complete classification of the possible images of 2-dimensional Galois representations with coefficients in local algebras over finite fields under the hypotheses that: (i) the square of the maximal ideal is zero, (ii) that the residual image is big (in a precise sense), and (iii) that the coefficient ring is generated by the traces. In odd characteristic, the image is completely determined by these conditions; in even characteristic the classification is much richer. In this case, the image is uniquely determined by the number of different traces of the representation, a number which is given by an easy formula. As an application of these results, the existence of certain p-elementary abelian extensions of big non-solvable number fields can be deduced. Whereas some aspects of class field theory are accessible through this approach, it can be applied to huge fields for which standard techniques totally fail. The second part of the thesis consists of an approach to p-adic uniformisations of Shimura curves X(Dp,N) through a combination of different techniques concerning rigid analytic geometry and arithmetic of quaternion orders. The results in this direction lean on two methods: one is based on the information provided by certain Mumford curves covering Shimura curves and the second one on the study of Eichler orders of level N in the definite quaternion algebra of discriminant D. Combining these methods, an explicit description of fundamental domains associated to p-adic uniformisation of families of Shimura curves of discriminant Dp and level N ≥ 1, for which the one-sided ideal class number h(D,N) is 1, is given. The method presented in this thesis enables one to find Mumford curves covering Shimura curves, together with a free system of generators for the associated Schottky groups, p-adic good fundamental domains and their stable reduction-graphs. As an application, general formulas for the reduction-graphs with lengths at p of the considered families of Shimura curves can be computed. [less ▲] Detailed reference viewed: 19 (8 UL)A variational formulation of dissipative quasicontinuum methods ; Beex, Lars ; et al in International Journal of Solids and Structures (2016), 102-103 Lattice systems and discrete networks with dissipative interactions are successfully employed as meso-scale models of heterogeneous solids. As the application scale generally is much larger than that of ... [more ▼] Lattice systems and discrete networks with dissipative interactions are successfully employed as meso-scale models of heterogeneous solids. As the application scale generally is much larger than that of the discrete links, physically relevant simulations are computationally expensive. The QuasiContinuum (QC) method is a multiscale approach that reduces the computational cost of direct numerical simulations by fully resolving complex phenomena only in regions of interest while coarsening elsewhere. In previous work (Beex et al., J. Mech. Phys. Solids 64, 154-169, 2014), the originally conservative QC methodology was generalized to a virtual-power-based QC approach that includes local dissipative mechanisms. In this contribution, the virtual-power-based QC method is reformulated from a variational point of view, by employing the energy-based variational framework for rate-independent processes (Mielke and Roub cek, Rate-Independent Systems: Theory and Application, Springer-Verlag, 2015). By construction it is shown that the QC method with dissipative interactions can be expressed as a minimization problem of a properly built energy potential, providing solutions equivalent to those of the virtual-power-based QC formulation. The theoretical considerations are demonstrated on three simple examples. For them we verify energy consistency, quantify relative errors in energies, and discuss errors in internal variables obtained for different meshes and two summation rules. [less ▲] Detailed reference viewed: 19 (3 UL)Connected Motorized Riders - A Smart Mobility System to Connect Two and Three-wheelers Sundharam, Sakthivel Manikandan ; ; Navet, Nicolas in Proceedings of 6th Intentional Symposium on Embedded computing & system Design (ISED 2016) (2016, December 15) The Smart Cities Mission has been launched in India in 2015 to develop 100 cities, with smart mobility being one of the main topics in the mission. As urban areas are flooded with two (motorcycles) and ... [more ▼] The Smart Cities Mission has been launched in India in 2015 to develop 100 cities, with smart mobility being one of the main topics in the mission. As urban areas are flooded with two (motorcycles) and three wheelers (auto-rickshaws), introducing smart control of such vehicles may reduce the congestion on the roads and the number of accidents. Indeed, over-speeding and drunken driving are common traffic violations. In this project we propose an IoT-based smart mobility system which tracks data, such as the vehicle location, vehicle speed, alcohol level of the driver, etc. efficiently over the internet. Our system has been conceived with CPAL, a high-level language meant to simulate and execute Cyber Physical Systems including IoT applications. A prototype running on ARM mbed IoT hardware, shows the feasibility of our concept. We believe that more efficient and interactive traffic management, more disciplined driving behaviors, reduction in accident rate, more controlled pollution, increased passenger safety can be achieved if systems like the one prototyped in this work deployed contributing to smarter cities. [less ▲] Detailed reference viewed: 44 (16 UL)A Model-Based Development Environment for Rapid-Prototyping of Latency-Sensitive Automotive Control Software Sundharam, Sakthivel Manikandan ; ; et al in Proceedings of 6th Intentional Symposium on Embedded computing & system Design (ISED 2016) (2016, December 15) The innovation in the field of automotive embedded systems has been increasingly relying on software-implemented functions. The control laws of these functions typically assume deterministic sampling ... [more ▼] The innovation in the field of automotive embedded systems has been increasingly relying on software-implemented functions. The control laws of these functions typically assume deterministic sampling rates and constant delays from input to output. However, on the target processors, the execution times of the software will depend on many factors such as the amount of interferences from other tasks, resulting in varying delays from sensing to actuating. Three approaches supported by tools, namely TrueTime, T-Res, and SimEvents, have been developed to facilitate the evaluation of how timing latencies affect control performance. However, these approaches support the simulation of control algorithms, but not their actual implementation. In this paper, we present a model interpretation engine running in a co-simulation environment to study control performances while considering the run-time delays in to account. Introspection features natively available facilitate the implementation of self-adaptive and fault-tolerance strategies to mitigate and compensate the run-time latencies. A DC servo controller is used as a supporting example to illustrate our approach. Experiments on controller tasks with injected delays show that our approach is on par with the existing techniques with respect to simulation. We then discuss the main benefits of our development approach that are the support for rapid-prototyping and the re-use of the simulation model at run-time, resulting in productivity and quality gains. [less ▲] Detailed reference viewed: 99 (30 UL)N-point Virasoro algebras are multi-point Krichever-Novikov type algebras Schlichenmaier, Martin Scientific Conference (2016, December 14) Detailed reference viewed: 5 (1 UL)Global converegence properties of a consensus protocol on the n-sphere Markdahl, Johan ; Goncalves, Jorge Scientific Conference (2016, December 13) This paper provides a novel analysis of the global convergence properties of a well-known consensus protocol for multi-agent systems that evolve in continuous time on the n-sphere. The feedback is ... [more ▼] This paper provides a novel analysis of the global convergence properties of a well-known consensus protocol for multi-agent systems that evolve in continuous time on the n-sphere. The feedback is intrinsic to the n-sphere, i.e., it does not rely on the use of local coordinates obtained through a parametrization. It is shown that, for any connected undirected graph topology and all n>1, the consensus protocol yields convergence that is akin to almost global consensus in a weak sense. Simulation results suggest that actual almost global consensus holds. This result is of interest in the context of consensus on Riemannian manifolds since it differs from what is known with regard to the 1-sphere and SO(3) where more advanced intrinsic consensus protocols are required in order to generate equivalent results. [less ▲] Detailed reference viewed: 54 (9 UL)Using Virtual Desktop Infrastructure to Improve Power Efficiency in Grinfy System Ibrahim, Abdallah Ali Zainelabden Abdallah ; Kliazovich, Dzmitry ; Bouvry, Pascal et al in IEEE 8th International Conference on Cloud Computing Technology and Science(CloudCom), Luxembourg 2016 (2016, December 13) Saving power becomes one of the main objectives in information technology industry and research. Companies consume a lot of money in the shape of power consuming. Virtual Desktop Infrastructure (VDI) is a ... [more ▼] Saving power becomes one of the main objectives in information technology industry and research. Companies consume a lot of money in the shape of power consuming. Virtual Desktop Infrastructure (VDI) is a new shape of delivering operating systems remotely. Operating systems are executing in a cloud data center. Users desktops and applications can be accessed by using thin client devices. Thin client device is consisting of screen attached with small CPU. VDI has benefits in terms of cost reduction and energy saving. In this paper, we increase the power saved by Grinfy system. Without VDI, Grinfy can save at least 30% of energy consumption to its users companies. By integrating VDI in computing systems and using Grinfy, the power efficiency and saving can be improved and save more than 30%. The improving and increasing of energy saving features of VDI are also illustrated by experiment and will be integrated to Grinfy system to increase percentage of energy saved. [less ▲] Detailed reference viewed: 22 (1 UL)Cohomologies and derived brackets of Leibniz algebras Cai, Xiongwei Doctoral thesis (2016) In this thesis, we work on the structure of Leibniz algebras and develop cohomology theories for them. The motivation comes from: • Roytenberg, Stienon-Xu and Ginot-Grutzmann's work on standard and naive ... [more ▼] In this thesis, we work on the structure of Leibniz algebras and develop cohomology theories for them. The motivation comes from: • Roytenberg, Stienon-Xu and Ginot-Grutzmann's work on standard and naive cohomology of Courant algebroids (Courant-Dorfman algebras). • Kosmann-Schwarzbach, Roytenberg and Alekseev-Xu's constructions of derived brackets for Courant algebroids. • The classical equivariant cohomology theory and the generalized geometry theory. This thesis consists of three parts: 1. We introduce standard cohomology and naive cohomology for a Leibniz algebra. We discuss their properties and show that they are isomorphic. By similar methods, we prove a generalization of Ginot-Grutzmann's theorem on transitive Courant algebroids, which was conjectured by Stienon-Xu. The relation between standard complexes of a Leibniz algebra and its corresponding crossed product is also discussed. 2. We observe a canonical 3-cochain in the standard complex of a Leibniz algebra. We construct a bracket on the subspace consisting of so-called representable cochains, and prove that the subspace becomes a graded Poisson algebra. Finally we show that for a fat Leibniz algebra, the Leibniz bracket can be represented as a derived bracket. 3. In spired by the notion of a Lie algebra action and the idea of generalized geometry, we introduce the notion of a generalized action of a Lie algebra g on a smooth manifold M, to be a homomorphism of Leibniz algebras from g to the generalized tangent bundle TM+T*M. We define the interior product and Lie derivative so that the standard complex of TM+T*M becomes a g differential algebra, then we discuss its equivariant cohomology. We also study the equivariant cohomology for a subcomplex of a Leibniz complex. [less ▲] Detailed reference viewed: 30 (10 UL)L'enseignement transsystémique du droit des contrats: l'expérience luxembourgeoise Ancel, Pascal Scientific Conference (2016, December 13) Detailed reference viewed: 8 (0 UL)La grande région SaarLorLux, riche de ses travailleurs frontaliers Pigeron-Piroth, Isabelle ; E-print/Working paper (2016) Detailed reference viewed: 19 (2 UL)Real-time error control for surgical simulation Bui, Huu Phuoc ; Tomar, Satyendra ; et al Poster (2016, December 12) Objective: To present the first real-time a posteriori error-driven adaptive finite element approach for real-time simulation and to demonstrate the method on a needle insertion problem. Methods: We use ... [more ▼] Objective: To present the first real-time a posteriori error-driven adaptive finite element approach for real-time simulation and to demonstrate the method on a needle insertion problem. Methods: We use corotational elasticity and a frictional needle/tissue interaction model based on friction. The problem is solved using finite elements within SOFA. The refinement strategy relies upon a hexahedron-based finite element method, combined with a posteriori error estimation driven local $h$-refinement, for simulating soft tissue deformation. Results: We control the local and global error level in the mechanical fields (e.g. displacement or stresses) during the simulation. We show the convergence of the algorithm on academic examples, and demonstrate its practical usability on a percutaneous procedure involving needle insertion in a liver. For the latter case, we compare the force displacement curves obtained from the proposed adaptive algorithm with that obtained from a uniform refinement approach. Conclusions: Error control guarantees that a tolerable error level is not exceeded during the simulations. Local mesh refinement accelerates simulations. Significance: Our work provides a first step to discriminate between discretization error and modeling error by providing a robust quantification of discretization error during simulations. [less ▲] Detailed reference viewed: 113 (18 UL)Elastography under uncertainty Hale, Jack ; ; Bordas, Stéphane Poster (2016, December 12) Detailed reference viewed: 62 (9 UL) |
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