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An octree-based proxy for collision detection in large-scale particle systems

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Science China(Information Sciences) 2013年第1期56卷 55-64页

作者： FAN WenShan WANG Bin paul jean-Claude SUN JiaGuang School of Software Tsinghua University Beijing Aerospace Control Center 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 Institut National de Recherche en Informatique et en Automatique(INRIA)

Particle systems are important building block for simulating vivid and detail-rich effects in virtual *** of the most difficult aspects of particle systems has been detecting collisions between particles and mesh *** to the huge computation,a variety of proxy-based approaches have been proposed recently to perform visually correct ***,all either limit the complexity of the scene,fail to guarantee non-penetration,or are too slow for real-time use with many *** this paper,we propose a new octree-based proxy for colliding particles with meshes on the *** approach works by subdividing the scene mesh with an octree in which each leaf node associates with a representative normal corresponding to the normals of the triangles that intersect the *** present a view-visible method,which is suitable for both closed and non-closed models,to label the empty leaf nodes adjacent to nonempty ones with appropriate back/front property,allowing particles to collide with both sides of the scene *** show how collisions can be performed robustly on this proxy structure in place of the original mesh,and describe an extension that allows for fast traversal of the octree structure on the *** experiments show that the proposed method is fast enough for real-time performance with millions of particles interacting with complex scenes.

关键词： particle systems collision detection octree-based proxy GPU

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

Endoscopic ultrasonography-guided fine needle aspiration:Relatively low sensitivity in the endosonographer population

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World Journal of Gastroenterology 2012年第19期18卷 2357-2363页

作者： jean-Marc Dumonceau Thibaud Koessler jeanin E van Hooft paul Fockens Division of Gastroenterology and Hepatology Geneva University Hospital1211 GenevaSwitzerland Division of General Internal Medicine Geneva University Hospital1211 GenevaSwitzerland Gastrointestinal Endoscopy Academic Medical Center University of Amsterdam1012 WXAmsterdamThe Netherlands

AIM:To assess the characteristics and quality of endoscopic ultrasonography-guided fine needle aspiration(EUS-FNA) in a large panel of ***:A survey was conducted during the 13th annual live course of endoscopic ultrasonography(EUS) held in Amsterdam,Netherlands.A 2-page questionnaire was developed for the *** validity of the questionnaire was determined based on input by experts in the field and a review of the relevant *** contained 30 questions that pertained to demographics and the current practice for EUS-FNA of responders,including sampling technique,sample processing,cytopathological diagnosis and sensitivity of EUS-FNA for the diagnosis of solid mass *** hundred and sixty-one endosonographers who attended the course were asked to answer the *** allowed assessing the current practice of EUS-FNA as well as the self-reported sensitivity of EUS-FNA for the diagnosis of solid mass *** also examined which factors were associated with a self-reported sensitivity of EUS-FNA for the diagnosis of solid mass lesions > 80%.RESULTS:Completed surveys were collected from 92(57.1%) of 161 endosonographers who attended the *** endosonographers had been practicing endoscopy and EUS for 12.5 ± 7.8 years and 4.8 ± 4.1 years,respectively;one third of them worked in a hospital with an annual caseload > 100 *** practices were located in 29 countries,including 13 countries in Western Europe that totaled 75.3% of the *** one third of endosonographers reported a sensitivity for the diagnosis of solid mass lesions > 80%(interquartile range of sensitivities,25.0%-75.0%).Factors independently associated with a sensitivity > 80% were(1) > 7 needle passes for pancreatic lesions or rapid on-site cytopathological evaluation(ROSE)(P < 0.0001),(2) a high annual hospital caseload(P = 0.024) and(3) routine isolation of microcores from EUS-FNA samples(P = 0.042).ROSE was routinely available to 27.9

关键词：灵敏度内镜超声人口穿刺引导 NA样本敏感性

Evidence of SARS-CoV-2 infection in pets,captive non-human primates and farm animals in Central Africa

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Asian Pacific Journal of Tropical Medicine 2022年第5期15卷 232-235页

作者： Gael D.Maganga barthelemy Ngoubangoye Jumafra P.Koumba Sonia Lekana-Douki Ivan C.Moussadji Kinga Thierry A.Tsoumbou Antoine M.Mbeang Beyeme Telstar G.Ndong Mebaley jean-Bernard Lekana-Douki Centre Interdisciplinaire de Recherches Medicales de Franceville(CIRMF) Unite Emergence des Maladies ViralesBP 769FrancevilleGabon Institut National Superieur d’Agronomie et de Biotechnologies(INSAB) Universite des Sciences et Techniques de Masuku(USTM)BP 941FrancevilleGabon Universite de Lyon Universite Lyon 1CNRSLaboratoire de Biometrie et Biologie evolutive UMR 555869622 VilleurbanneFrance LabEx ECOFECT Eco-evolutionary Dynamics of Infectious DiseasesUniversity of LyonLyonFrance

It has been reported that the host of SARS-CoV-2 can be extremely wide due to the conservation of angiotensin converting enzyme 2 in mammals[1].Several studies have reported natural or experimental infection with SARS-CoV-2 in pets,farm and captive wild animals[2-4].However,to the best of our knowledge,there was no published study assessing virus circulation among domestic or captive animals in Central,West and East *** this study,we assessed the presence and circulation of SARS-CoV-2 or other betacoronaviruses in pets,livestock and animals kept in captivity in conservation centers in Haut-Ogoouéprovince,southeastern Gabon.

关键词： Central southeastern Africa

Amenability With Respect to a Closed Subgroup of a Product Group

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数学进展 1992年第1期 97-112页

作者： jean-paul Pier Seminaire de Mathematique Centre Universitaire de Lurembour

In this paper, the concept of amenability with respect to a closed subgroup of a product group (г-amenability), which is a generalization of amenability and inner-amenability under the usual sense, is introduced. Various characterizations of г-amenability reflecting classical descriptions of amenability,and comments on related problems are also elaborated.

关键词： Amenability With Respect to a Closed Subgroup of a Product Group

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

Comparison of airway resistance measurements by the forced oscillation technique and the interrupter technique for detecting chronic obstructive pulmonary disease in elderly patients

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Chinese Medical Journal 2005年第22期118卷 1921-1924页

作者： GUO Yan-fei SUN Tie-ying Francois Herrmann jean-paul Janssens Division of Pulmonary Medicine Beijing Hospital Beijing 100730China Department of Rehabilitation and Geriatrics Geneva University Hospital Geneva Switzerland Division of Pulmonary Medicine Geneva University HospitalGeneva Switzerland

Rulmonary function tests provide an objective means to verify ventilatory dysfunction and to estimate its severity in respiratory disorders. Measurement of forced expiratory volume in 1 second （FEV1） and forced vital capacity （FVC） is considered to be the basic tests for the assessment of airway obstruction. Although they are useful diagnostically and prognostically, the results of FEV1 and FVC are strongly dependent on the cooperation of the patient. Lack of collaboration is particularly present in elderly patients because of mood alterations, fatigability or cognitive impairment. The forced oscillation technique （FOT） and the interrupter resistance technique are the two methods of measuring respiratory resistance during tidal breathing, they are of special interest because both of them are noninvasive, requires minimal cooperation, takes little time and can be easily repeated, especially in children and elderly subjects who cannot accomplish forced expiratory maneuvers in a reproducible manner.

关键词： forced oscillation technique· interrupter technique·chronic obstructive pulmonary disease

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