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Simulating Human Visual Perception in Nighttime Illumination

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Tsinghua Science and Technology 2009年第1期14卷 133-138页

作者：周宁董未名王家廞 paul jean-Claude Department of Computer Science and Technology Tsinghua University INRIA Lorraine

This paper presents an image-based algorithm for simulating the visual adaptation of the human visual system to various illuminations, especially in dark nighttime conditions. The human visual system exhibits different characteristics depending on the illumination intensity, with photopic vision in bright conditions, scotopic vision in dark conditions, and mesopic vision between these two. A computational model is designed to simulate multiple features of mesopic vision and scotopic vision, including the chromaticity change, luminance change, and visual acuity loss. The system uses a source image under bright illumination as input. Then assuming that the viewer has already adapted to the new conditions, the color spectrum of the input image is reconstructed to replace the source with modifications of the chromaticity and the luminance of the relighted scene. A bilateral filter is used to simulate the visual acuity loss. The model parameters have clear physical meanings and can be obtained from experimental data to achieve realistic *** algorithm can be used not only for visual perception simulation, but also as a day-for-night tool to produce realistic nighttime images from daytime images.

关键词： Image enhancement

Adding body load modifies the vibratory sensation of the foot sole and affects the postural control

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Military Medical Research 2019年第1期6卷 60-66页

作者： Yves Jammes Eva Ferrand Corentin Fraud Alain Boussuges jean paul Weber School of Podiatry C2VN Inra Inserm Faculty of Medicine Aix Marseille University

Background: Heavy backpacks are often used by soldiers and firefighters. Weight carrying could reduce the speed and efficiency in task completion by altering the foot sole sensitivity and postural ***: In fifteen healthy subjects, we measured the changes in sensitivity to vibrations applied to the foot sole when standing upright or walking after load carrying(30% body weight). The participants were asked to judge different vibration amplitudes applied on the 2 nd or 5 th metatarsal head and the heel at two frequencies(25 and 150 Hz) to determine the vibration threshold and the global perceptual representation(Ψ)of the vibration amplitude(Φ)given by the Stevens power function(Ψ=k×Φ~n). Any increase in negative k value indicated a reduction in sensitivity to the lowest loads. Pedobarographic measurements, with computation of the center of pressure(COP) and its deviations, were performed during weight ***: The 25-Hz vibration threshold significantly increased after weight carrying when standing upright or *** standing with the added loads, the absolute negative k value increased for the 25 Hz frequency. After walking with the added loads, the k coefficient increased for the two vibration frequencies. Weight carrying significantly increased both the CoP surface and CoP lateral ***: Our data show that weight carrying reduces the sensory pathways from the foot sole and accentuates the center of pressure deviations.

关键词： Foot sole sensitivity Vibration Weight carrying Postural control

Formal verification of synchronous data-flow program transformations toward certified compilers

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Frontiers of Computer Science 2013年第5期7卷 598-616页

作者： Van Chan NGO jean-Pierre TALPIN Thierry GAUTIER paul Le GUERNIC Loic BESNARD INRIA Rennes-Bretagne Atlantique Rennes 35042 France IRISA/CNRS Rennes 35042 France

Translation validation was invented in the 90＇s by Pnueli et al. as a technique to formally verify the correctness of code generators. Rather than certifying the code generator or exhaustively qualifying it, translation validators attempt to verify that program transformations preserve semantics. In this work, we adopt this approach to formally verify that the clock semantics and data dependence are preserved during the compilation of the Signal compiler. Translation valida- tion is implemented for every compilation phase from the initial phase until the latest phase where the executable code is generated, by proving the transformation in each phase of the compiler preserves the semantics. We represent the clock semantics, the data dependence of a program and its trans- formed counterpart as first-order formulas which are called clock models and synchronous dependence graphs （SDGs）, respectively. We then introduce clock refinement and depen- dence refinement relations which express the preservations of clock semantics and dependence, as a relation on clock mod- els and SDGs, respectively. Our validator does not require any instrumentation or modification of the compiler, nor any rewriting of the source program.

关键词： formal verification translation validation certi-fied compiler multi-clocked synchronous programs embed-ded systems.

Towards a verified compiler prototype for the synchronous language SIGNAL

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Frontiers of Computer Science 2016年第1期10卷 37-53页

作者： Zhibin YANG jean-paul BODEVEIX Mamoun FILALI Kai HU Yongwang ZHAO Dianfu MA College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China IRIT-CNRS Universite de Toulouse Toulouse 31062 France State Key Laboratory of Software Development Environment Beihang University Beijing 100191 China

SIGNAL belongs to the synchronous languages family which are widely used in the design of safety-critical real-time systems such as avionics, space systems, and nu- clear power plants. This paper reports a compiler prototype for SIGNAL. Compared with the existing SIGNAL com- piler, we propose a new intermediate representation （named S-CGA, a variant of clocked guarded actions）, to integrate more synchronous programs into our compiler prototype in the future. The front-end of the compiler, i.e., the transla- tion from SIGNAL to S-CGA, is presented. As well, the proof of semantics preservation is mechanized in the theo- rem prover Coq. Moreover, we present the back-end of the compiler, including sequential code generation and multi- threaded code generation with time-predictable properties. With the rising importance of multi-core processors in safety- critical embedded systems or cyber-physical systems （CPS）, there is a growing need for model-driven generation of multi- threaded code and thus mapping on multi-core. We propose a time-predictable multi-core architecture model in archi- tecture analysis and design language （AADL）, and map the multi-threaded code to this model.

关键词： synchronous languages SIGNAL guarded ac-tions verified compiler Coq architecture analysis and designlanguage (AADL)

Supervised Machine Learning Approach Based Adaptive Modulation Order Selection in Spatial Modulation

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Supervised Machine Learning Approach Based Adaptive Modulati...

作者： TWARAYISENZE jean paul 山东大学

学位级别：硕士

In wireless communications,spatial modulation（SM）is a simple and promising multiple-input multiple-output（MIMO）technology to overcome the drawbacks existing in conventional MIMO systems for the inherent characteristics,e.g.,the activation of single transmit antenna per each symbol period to avoid inter-channel interference（ICI）and inter-antenna synchronization（IAS）.SM can also reduce the transmit power due to the activation of one transmit antenna and achieve high bit rate by additional bits conveyed by the activated antenna *** the other hand,SM is very sensitive to channel fading and *** deal with this issue,adaptive modulation order selection（MOS）is adopted in SM,where different modulation orders can be adjusted to the available channel conditions to enhance the system bit error rate（BER）***,the classical optimal adaptive MOS in SM is usually performed through conducting an exhaustive search（ES）over all the received symbols,which results in high system ***,machine learning（ML）technique has proved the efficient reduction of complexity in SM-MIMO *** this thesis,we employ supervised learning,which is a ML task of learning a function that maps an input to an output based on a labeled training ***,we utilize supervised ML technique to select the optimal modulation order in SM and provide an effective complexity-performance tradeoff under the given spectral efficiency（SE）.The main contributions of this thesis focus on the ***,two supervised machine learning classifiers（MLCs）,K-nearest neighbors（KNN）and support vector machine（SVM）are proposed to convert the classical adaptive MOS optimization problem into a multi-class classification problem and predict the modulation order candidate which provides the maximum minimum Euclidean distance（MED）by training the relevant *** a result,the system complexity is significantly reduced at the cost of marginal BER performance ***,to fu

关键词： multiple-input multiple-output Spatial modulation modulation order selection K-nearest neighbors support vector machine artificial neural network

An Interpretation of the Poincare Morphism for Compact Toric Varieties

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Chinese Quarterly Journal of Mathematics 1995年第4期10卷 1-7页

作者： jean－paul BRASSEL CIRM－Marsille－France SiGmA

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关键词： POINCARE射紧复曲面簇拓扑空间

Polychronous automata and their use for formal validation of AADL models

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Frontiers of Computer Science 2019年第4期13卷 677-697页

作者： Thierry GAUTIER Clement GUY Alexandre HONORAT paul LE GUERNIC jean-Pierre TALPIN Loic BESNARD Univ. Rennes Inria Rennes-Bretagne-Atlantique Research Centre F-35000 Rennes France Univ. Rennes CNRS IRISA F-35000 Rennes France

This paper investigates how state diagrams can be best represented in the polychronous model of computation (MoC) and proposes to use this model for code validation of behavior specifications in architecture analysis & design language (AADL). In this relational MoC, the basic objects are signals, which are related through dataflow equations. Signals are associated with logical clocks, which provide the capability to describe systems in which components obey multiple clock rates. We propose a model of finite-state automata, called polychronous automata, which is based on clock relationships. A specificity of this model is that an automaton is submitted to clock constraints, which allows one to specify a wide range of control-related configurations, being either reactive or restrictive with respect to their control environment. A semantic model is defined for these polychronous automata, which relies on boolean algebra of clocks. Based on a previously defined modeling method for AADL software architectures using the polychronous MoC, the proposed model is used as a formal model for the AADL behavior annex. This is illustrated with a case study involving an adaptive cruise control system.

关键词： architecture modeling formal semantics finitestate automaton polychronous model synchronous concurrency code generation AADL

Shallow water equations for power law and Bingham fluids Dedicated to the NSFC-CNRS Chinese-French summer institute on fluid mechanics in 2010

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Science China Mathematics 2012年第2期55卷 277-283页

作者： FERNANDEZ-NIETO Enrique D. NOBLE Pascal VILA jean-paul Departamento de Matemdtica Aplicada I Universidad de Sevilla 41012 Sevilla Spain Universite de Lyon Universitd Lyon1 Institut Camille Jordan UMR CNRS 520843 blvd du 11 novembre 1918 F-69622 ViUeurbanne Cedex France Institut de Mathdmatiques de Toulouse UMR CNRS 5219 INSA de Toulouse 135 avenue de Rangueil 31077 Toulouse Cedex 4 France

In this note, we provide a consistant thin layer theory for power law and Bingham incompressible fluids flowing down an inclined plane under the effect of gravity. The derivation of such equations is based on formal asymptotic expansions of solutions of Cauchy momentum equations in the shallow water scaling and in the neighbourhood of steady solutions so that we can close the average equations on the fluid height h and the total discharge rate q.

关键词： shallow water equations asymptotic analysis non-Newtonian fluids

B-spline surface fitting to mesh vertices

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Science China(Information Sciences) 2017年第7期60卷 259-261页

作者： Yang LU Junhai YONG Kanle SHI Hejin GU Ping ZHENG jean-Claude paul School of Software Tsinghua University Department of Computer Science and Technology Tsinghua University Key Laboratory for Information System Security Ministry of Education of China Tsinghua National Laboratory for Information Science and Technology Tsinghua University Department of Research & Development Jiangxi Academy of Science Department of Mathematics and Computer Science Nanchang Normal University

Here we propose a novel method of fitting B-spline surfaces to input mesh *** a mesh model that is difficult to fit with one B-spline surface,we divide it into several patches that form a tree structure(which is called hierarchical splines[1]),and for each patch,we use one B-spline surface for ***,only a few patches are required,and G2continuity can be achieved between the adjacent surfaces.

关键词： B-spline surface fitting to mesh vertices