Articles de revues : « Hypothèse de la simulation »

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Dessalles, Jean-Louis. « Et si la coopération était un mythe ? Un pilier des sciences sociales ébranlé par la simulation ». Nouvelles perspectives en sciences sociales 5, n^o 2 (6 juillet 2010) : 79–89. http://dx.doi.org/10.7202/044077ar.

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Résumé De nombreux auteurs voient dans la coopération le ciment des sociétés humaines. Plus que les autres animaux, les humains seraient capables de renoncer à des bénéfices immédiats pour en faire profiter autrui, dans l’espoir d’une réciprocité future. Or, cette hypothèse est mise à mal par la simulation : les agents qui ne coopèrent pas, ou qui coopèrent moins, en ressortent gagnants. J’explore une autre hypothèse, inspirée par la modélisation du langage. Les actes qui nous semblent coopératifs seraient en réalité des signaux. Les individus ne se montrent pas prosociaux par calcul, mais pour afficher des qualités qui se trouvent être essentielles, dans notre espèce, pour se faire accepter en tant qu’ami et ainsi constituer un réseau social.

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COLSON, F., et V. CHATELLIER. « La nouvelle réforme de la PAC (Agenda 2000) : baisse modérée des revenus et accroissement des aides directes pour les producteurs français de viande bovine ». INRAE Productions Animales 12, n^o 3 (1 juin 1999) : 171–82. http://dx.doi.org/10.20870/productions-animales.1999.12.3.3877.

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Les chefs des Etats et des gouvernements ont adopté, lors du conseil européen qui se tenait à Berlin le 25 mars 1999, les bases d’une future réforme de la politique agricole commune (Agenda 2000). Cet article présente les résultats d’une simulation des conséquences de cet accord pour les exploitations agricoles françaises réparties selon cinq types de production, puis, de façon plus précise, pour les seules exploitations bovins-viande. Ces simulations, qui sont réalisées à structure constante et à horizon 2004 (hors réforme de l’OCM lait) sur la base des informations du RICA, conduisent à une baisse mécanique de revenu plus forte pour les exploitations céréalières (-18%) que pour les exploitations bovins-viande (-7%) et laitières (-3%). La prise en considération d’une hypothèse de gains de productivité technique (hausse des rendements et réduction du montant des consommations intermédiaires) permet cependant de modérer ces variations simulées de revenus. Cette réforme renforce une nouvelle fois le rôle des paiements directs dans la formation du revenu des agriculteurs, notamment celui des producteurs de viande bovine, et pose avec plus d’acuité la question de leur légitimité.

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Walckiers, Pierre. « Les articulations des régimes de vérité et des modes d’existence. Une approche foucaldienne pour analyser les rapports entre science et droit ». Revue interdisciplinaire d'études juridiques Volume 91, n^o 2 (20 décembre 2023) : 197–220. http://dx.doi.org/10.3917/riej.091.0197.

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Dans le cadre de nos recherches sur l’utilisation des discours scientifiques dans les sphères juridiques et de critiques concernant le risque de les utiliser comme arguments d’autorité, cet article présentera et comparera l’approche foucaldienne des « régimes de vérité » avec l’approche des « modes d’existence » de Latour, Gutwirth et Stengers. Dans la première partie, nous analyserons le droit et la science du point de vue des régimes de vérité et de leurs articulations. Un régime de vérité désigne un ensemble de règles et d’obligations qui déterminent les procédures à suivre par le sujet pour accéder à la vérité. La vérité est construite et spécifique à chaque régime (droit, science, religion, etc.). Notre deuxième partie abordera les modes d’existence. Ce concept met en évidence les contraintes ontologiques et les engagements d’un sujet dans la construction d’un énoncé vrai. Notre hypothèse est que les deux approches (les régimes de vérité et les modes d’existence) peuvent être à la fois utiles et complémentaires pour comprendre la relation entre le droit et la science. En effet, l’approche foucaldienne met en garde contre les articulations des différents régimes, tandis que les modes d’existence nous alertent sur le risque de commettre une potentielle « erreur de catégorie » en confondant les rôles, les fonctions et les pratiques propres à chaque régime. Par exemple, cela se produit lorsque l’on critique un jugement juridique pour ne pas être scientifiquement correct.

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Shelburne, Kevin. « Investigating ACL Failure Hypotheses with Simulation ». Medicine & ; Science in Sports & ; Exercise 40, Supplement (mai 2008) : 62. http://dx.doi.org/10.1249/01.mss.0000321255.11965.74.

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Lu, Maozu, Grayham E. Mizon et Chiara Monfardini. « Simulation Encompassing : Testing Non-nested Hypotheses* ». Oxford Bulletin of Economics and Statistics 70 (décembre 2008) : 781–806. http://dx.doi.org/10.1111/j.1468-0084.2008.00530.x.

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Vautrin, Denis, Irmela Zentner, Guy D’Urso, Géry Hachet, Christophe Vergniault et Dimitri Mercadier. « Démarche de qualification de l’utilisation de la méthode MASW sur les digues par mesures en environnement contrôlé et simulations pour évaluer l’influence de la géométrie 3D des ouvrages ». Revue Française de Géotechnique, n^o 178 (2024) : 2. http://dx.doi.org/10.1051/geotech/2024005.

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Les digues de protection contre les inondations peuvent faire l’objet de campagnes de reconnaissance dans le but d’identifier d’éventuelles zones de faiblesse et de prévenir tout risque de défaillance. La méthode Multi-channel Analysis of Surface Waves (MASW), non invasive et à faible coût, offre un complément intéressant aux sondages géotechniques. Elle est notamment utile pour les ouvrages de grand linéaire car elle est employable en mode « grand rendement ». Cependant, la méthode MASW repose sur une hypothèse de milieu 1D stratifié, c’est-à-dire que la surface du sol ainsi que les interfaces entre les différentes couches de sol sont supposées horizontales. Cela n’est a priori pas compatible avec la topographie 3D de l’ouvrage. Nous avons réalisé une étude de sensibilité des résultats de MASW à la géométrie 3D d’une digue en nous appuyant à la fois sur des mesures expérimentales et sur des simulations. L’ouvrage considéré est une maquette de digue à l’échelle 1. Dans un premier temps, nous avons proposé une méthodologie de simulation permettant de reproduire numériquement la propagation d’une onde sismique en 3D pour la configuration de la maquette, et nous avons validé ce modèle par comparaison entre signaux numériques et acquisitions réelles. Dans un second temps, nous avons considéré différentes configurations de simulation dans le but d’évaluer l’influence de la géométrie 3D de l’ouvrage. D’après les résultats obtenus, la géométrie 3D de la digue entraîne une sous-estimation de la profondeur de l’interface entre la digue et le sol. En revanche, son influence sur l’estimation des caractéristiques des couches est négligeable. Ces résultats sont en accord avec le retour d’expérience terrain d’EDF. D’autres limites restent à approfondir par de nouvelles simulations, en considérant des ouvrages de plus grandes dimensions et à géométries plus complexes. De plus, l’exploitation de la maquette de digue se poursuivra avec la mise en œuvre de méthodes électriques, et avec des travaux sur les méthodes de fusion de données.

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Herrera, Rémy. « Dépenses publiques d'éducation et capital humain dans un modèle convexe de croissance endogène ». Revue économique 49, n^o 3 (1 mai 1998) : 831–44. http://dx.doi.org/10.3917/reco.p1998.49n3.0831.

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Résumé L'objet de cette contribution est de proposer un modèle convexe d'équilibre général dynamisé avec croissance endogène par accumulation de capital humain dans un secteur public d'éducation. Le point nodal de l'axiomatique permettant cette croissance auto-entretenue est une hypothèse de substituabilité entre travail qualifié et travail non qualifié. Les simulations de ce modèle montrent l'impact positif des dépenses publiques d'éducation sur le taux de croissance du PIB de long terme de l'économie.

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Gualeni, Stefano. « A Theodicy for Artificial Universes ». International Journal of Technoethics 12, n^o 1 (janvier 2021) : 21–31. http://dx.doi.org/10.4018/ijt.2021010102.

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“Simulation hypotheses” are imaginative scenarios that are typically employed in philosophy to speculate on how likely it is that one is currently living within a simulated universe as well as on the possibility for ever discerning whether one does in fact inhabit one. These philosophical questions in particular overshadowed other aspects and potential uses of simulation hypotheses, some of which are foregrounded in this article. More specifically, “A Theodicy for Artificial Universes” focuses on the moral implications of simulation hypotheses with the objective of speculatively answering questions concerning computer simulations such as: If one is indeed living in a computer simulation, what might be its purpose? What aspirations and values could be inferentially attributed to its alleged creators? And would living in a simulated universe affect the value and meaning one attributes to the existence?

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Côté-Sergent, Aurélie, Jean-Yves Duclos, Alexandre Lekina, Steeve Marchand et Pierre-Carl Michaud. « Projections de l’état de santé de la population québécoise et impacts sur le risque de longévité d’un régime de retraite à prestations déterminées ». L'Actualité économique 91, n^o 4 (9 août 2016) : 567–98. http://dx.doi.org/10.7202/1037213ar.

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Nous nous intéressons au risque futur de longévité étant donné l’augmentation de l’espérance de vie due au progrès technologique et la hausse de la prévalence de maladies liées à l’obésité et à la sédentarité. Nous utilisons dans un premier temps des techniques de microsimulation afin de projeter l’état de santé de la population québécoise dans divers scénarios, en incluant dans cette microsimulation une hypothèse d’amélioration exogène de la mortalité semblable à celle faite par la Régie des rentes du Québec (RRQ). Nous évaluons dans un deuxième temps les implications des tendances en santé fournies par ces simulations pour le ratio de financement de régimes de retraite à prestations déterminées (hypothétiques). Il s’avère qu’en 2050, le ratio de financement des scénarios alternatifs pourrait être entre 3 % et 18 % plus faible que celui du scénario de référence, indiquant que des changements dans l’évolution de l’état de santé pourraient avoir des effets importants sur les régimes de retraite dans le futur. Nous analysons dans un dernier temps les hypothèses de mortalité faites par la RRQ en considérant des scénarios alternatifs associés à des avancées médicales susceptibles de se produire dans les 10 prochaines années. Il s’avère selon cette analyse que les hypothèses de la RRQ pourraient surestimer significativement la croissance de l’espérance de vie future, en particulier celle des individus de 30 à 65 ans.

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Locatelli, M., L. Pellegrini, D. Accardo, E. Sulis, L. C. Tagliabue et G. M. Di Giuda. « People flow management in a healthcare facility through crowd simulation and agent-based modeling methods ». Journal of Physics : Conference Series 2600, n^o 14 (1 novembre 2023) : 142007. http://dx.doi.org/10.1088/1742-6596/2600/14/142007.

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Abstract The study investigates the optimization of user flow and space management in a hospital located in Turin by simulating activities and patient flows of the blood drawing center. The simulation aims to verify the maximum number of people allowed to occupy the spaces simultaneously, manage user flows, and verify compliance with COVID-19 pandemic restrictions. Pedestrian Dynamics, supported by Building Information Modeling (BIM) methods, and NetLogo are used to simulate and optimize user flow and space management relying on crowd simulation and Agent-Based Modeling. Patients’ movements and hospital activities are modeled to identify bottlenecks, crowded situations, and other issues. The methodology also allows the comparison of the two selected tools via the two simulations that are set with equal parameters. The results of the simulations enabled the analysis of current conditions and the testing of scenarios and hypotheses without inconveniencing users and interrupting hospital activities. Some improvements in space and people flow management could be proposed, e.g., distributing patients’ entries over the center opening times via an online booking system and modifying room functions. The proposed improvements support the facility managers to avoid, or at least minimize, crowded situations during which is not possible for patients to comply with COVID-19 pandemic restrictions, while minimizing layout changes and consequently the costs and efforts of implementing the changes. The proposed methodology will enable better management of future emergencies in healthcare facilities. The tool comparison will support future studies on simulation tool selection according to simulation and stakeholder needs.

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Stutz, Timothy C., Alfonso Landeros, Jason Xu, Janet S. Sinsheimer, Mary Sehl et Kenneth Lange. « Stochastic simulation algorithms for Interacting Particle Systems ». PLOS ONE 16, n^o 3 (2 mars 2021) : e0247046. http://dx.doi.org/10.1371/journal.pone.0247046.

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Interacting Particle Systems (IPSs) are used to model spatio-temporal stochastic systems in many disparate areas of science. We design an algorithmic framework that reduces IPS simulation to simulation of well-mixed Chemical Reaction Networks (CRNs). This framework minimizes the number of associated reaction channels and decouples the computational cost of the simulations from the size of the lattice. Decoupling allows our software to make use of a wide class of techniques typically reserved for well-mixed CRNs. We implement the direct stochastic simulation algorithm in the open source programming language Julia. We also apply our algorithms to several complex spatial stochastic phenomena. including a rock-paper-scissors game, cancer growth in response to immunotherapy, and lipid oxidation dynamics. Our approach aids in standardizing mathematical models and in generating hypotheses based on concrete mechanistic behavior across a wide range of observed spatial phenomena.

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Hima, Amara, Abdelmalek Tacherift et Abdelkader Abdellaoui. « Le dysfonctionnement socio-spatial des grands ensembles en Algérie : technique de l’analyse wayfinding par méthode “movement traces” et l’analyse morphologique (syntaxe spatiale) par logiciel “depthmap” ». urbe. Revista Brasileira de Gestão Urbana 10, n^o 2 (8 mars 2018) : 268–88. http://dx.doi.org/10.1590/2175-3369.010.002.ao12.

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Résumé La technique de l’analyse syntaxique de la visibilité (Visibility Graph Analysis – VGA) et de l’accessibilité (All Line Analysis – ALA) par logiciel “DepthMap©(UCL, Londres)” et l’analyse du dysfonctionnement wayfinding par méthode “movement traces”, sont utilisées dans ce papier afin de développer un modèle d’analyse et d’investigation de l’impact des changements spatiaux sur le dysfonctionnement socio-spatial du wayfinding, ainsi sur la reproduction urbaine, notamment les transformations des façades et l’appropriation des espaces extérieurs dans les grands ensembles en Algérie. Nous donnons ici le cas d’étude de la cité 1000 logt-Biskra et la cité 500 logt-M’sila. Afin de vérifier cette hypothèse, un modèle d’analyse hybride a été développé par croisement des résultats d’analyses des deux techniques. Par conséquent, le schéma de l’interférence montre que la majorité des piétons préfèrent parcourir les axes courts et droits — caractérisés par une forte propriété syntaxique de visibilité et d’accessibilité (l’intégration, la connectivité et l’intelligibilité) — en directions des équipements adjacents et aux milieux des deux cités. Ces itinéraires ont un impact sur les transformations des façades et l’appropriation des espaces extérieurs. Le modèle développé promet de futures recherches sur le plan de la quantification, la modélisation et la simulation du processus de la reproduction urbaine, notamment par les automates cellulaires.

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Lukács, Gáspár. « POSSA : Power simulation for sequential analyses and multiple hypotheses ». Journal of Open Source Software 7, n^o 76 (28 août 2022) : 4643. http://dx.doi.org/10.21105/joss.04643.

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Buslaev, Alexander P., Maria Ju Fomina, Alexander G. Tatashev et Marina V. Yashina. « On discrete flow networks model spectra : statements, simulation, hypotheses ». Journal of Physics : Conference Series 1053 (juillet 2018) : 012034. http://dx.doi.org/10.1088/1742-6596/1053/1/012034.

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Beiko, Robert G., et Robert L. Charlebois. « A simulation test bed for hypotheses of genome evolution ». Bioinformatics 23, n^o 7 (31 janvier 2007) : 825–31. http://dx.doi.org/10.1093/bioinformatics/btm024.

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Rizana, Afrin Fauzya, et Fadillah Ramadhan. « Multi-Agent Simulation in the Inter-Organizational Trust Model and Knowledge Sharing in the Automotive Industry ». Jurnal Teknik Industri 20, n^o 2 (31 août 2019) : 161. http://dx.doi.org/10.22219/jtiumm.vol20.no2.161-171.

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Two organizations can share knowledge to determine the success of their collaboration. Effectiveness in sharing knowledge affect the organizational performance and trust between organizations. This study aims to identify the implementation of multi-agent simulations to increase confidence in sharing knowledge between organizations. A multi-agent simulation approach was used in this study. The research model was adopted from previous research. Several hypotheses and path coefficients had tested in simulation models. The results of this study showed that multi-agent simulation is suitable to be implemented as a problem-solving method for a complex problem such as knowledge sharing. Besides, this study found the role of individual factors such as likability and expertise on the success of sharing knowledge between organizations.

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Rizana, Afrin Fauzya, et Fadillah Ramadhan. « Multi-Agent Simulation in the Inter-Organizational Trust Model and Knowledge Sharing in the Automotive Industry ». Jurnal Teknik Industri 20, n^o 2 (31 août 2019) : 57. http://dx.doi.org/10.22219/jtiumm.vol20.no2.57-67.

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Two organizations can share knowledge to determine the success of their collaboration. Effectiveness in sharing knowledge affect the organizational performance and trust between organizations. This study aims to identify the implementation of multi-agent simulations to increase confidence in sharing knowledge between organizations. A multi-agent simulation approach was used in this study. The research model was adopted from previous research. Several hypotheses and path coefficients had tested in simulation models. The results of this study showed that multi-agent simulation is suitable to be implemented as a problem-solving method for a complex problem such as knowledge sharing. Besides, this study found the role of individual factors such as likability and expertise on the success of sharing knowledge between organizations.

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Parnovsky, S. « N-body simulations : advantages and problems ». Bulletin of Taras Shevchenko National University of Kyiv. Astronomy, n^o 65 (2022) : 20–21. http://dx.doi.org/10.17721/btsnua.2022.65.20-21.

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The N-body simulations method is widely used in astrophysics and cosmology. The article briefly lists its advantages, disadvantages and possible errors. It is concluded that the results of computer simulation not only cannot replace the data of astronomical observations, but also are not a sufficient reason to reject new hypotheses that do not have other drawbacks, other than the discrepancy between their conclusions and the results of N-body simulations.

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Jones, Thomas C., et Thomas F. Laughlin. « PopGen Fishbowl : A Free Online Simulation Model of Microevolutionary Processes ». American Biology Teacher 72, n^o 2 (1 février 2010) : 100–103. http://dx.doi.org/10.1525/abt.2010.72.2.9.

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Natural selection and other components of evolutionary theory are known to be particularly challenging concepts for students to understand. To help illustrate these concepts, we developed a simulation model of microevolutionary processes. The model features all the components of Hardy-Weinberg theory, with population size, selection, gene flow, nonrandom mating, and mutation all being demonstrated in the simulations. By using this freely available computer model, students can develop and test hypotheses with replicated virtual experiments. Because the model is an agent-based simulation, there is biologically realistic variability in the results. Students using the model see results both numerically and graphically, and these are reinforced by an animation of the virtual fish in the simulated experiment.

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Hines, M. L., et N. T. Carnevale. « The NEURON Simulation Environment ». Neural Computation 9, n^o 6 (1 août 1997) : 1179–209. http://dx.doi.org/10.1162/neco.1997.9.6.1179.

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The moment-to-moment processing of information by the nervous system involves the propagation and interaction of electrical and chemical signals that are distributed in space and time. Biologically realistic modeling is needed to test hypotheses about the mechanisms that govern these signals and how nervous system function emerges from the operation of these mechanisms. The NEURON simulation program provides a powerful and flexible environment for implementing such models of individual neurons and small networks of neurons. It is particularly useful when membrane potential is nonuniform and membrane currents are complex. We present the basic ideas that would help informed users make the most efficient use of NEURON.

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Kragh, John F., Tuan D. Le et Michael A. Dubick. « Exploring Tourniquet Conversion in Simulation to Develop Concepts and Hypotheses ». Journal of Special Operations Medicine 21, n^o 3 (2021) : 23. http://dx.doi.org/10.55460/j859-5awq.

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Pichugin, Yury A. « Geometrical aspects of testing complex statistical hypotheses in mathematical simulation ». St. Petersburg Polytechnical University Journal : Physics and Mathematics 1, n^o 2 (juin 2015) : 181–91. http://dx.doi.org/10.1016/j.spjpm.2015.07.001.

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Barbujani, Guido, Robert R. Sokal et Neal L. Oden. « Indo-European origins : A computer-simulation test of five hypotheses ». American Journal of Physical Anthropology 96, n^o 2 (février 1995) : 109–32. http://dx.doi.org/10.1002/ajpa.1330960202.

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Porto, Fabio, Ramon G. Costa, Ana Maria de C. Moura et Bernardo Gonçalves. « Modeling and Implementing Scientific Hypothesis ». Journal of Database Management 26, n^o 2 (avril 2015) : 1–13. http://dx.doi.org/10.4018/jdm.2015040101.

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Computational Simulations are important tools that enable scientists to study complex phenomena about which few data is available or that require dangerous human interventions. They involve complex and heterogeneous components, including: mathematical equations, hypothesis, computational models and data. In order to support in-silico scientific research this complex environment needs to be modeled and have its data and metadata managed enabling model evolution, prediction analysis and decision-making. This paper proposes a scientific hypothesis conceptual model that allows scientists to represent the phenomenon been investigated, the hypotheses formulated in the attempt to explain it, and provides the ability to store results of experiment simulations with their corresponding provenance metadata. The proposed model supports scientific life-cycle through: provenance management, exchange of hypothesis as data, experiment reproducibility, model steering and simulation result analyses. A cardiovascular numerical simulation illustrates the applicability of the model and an initial implementation using SciDB is discussed.

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Dundović, Čedomir, Mirko Bilić et Joško Dvornik. « Contribution to the Development of a Simulation Model for a Seaport in Specific Operating Conditions ». PROMET - Traffic&Transportation 21, n^o 5 (2 mars 2012) : 331–40. http://dx.doi.org/10.7307/ptt.v21i5.248.

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The purpose of this paper is to show the efficiency of application of system dynamic simulation modelling when researching the behaviour dynamics of the port transhipment process, and finding the optimal solution for cargo handling with regard to the type and scope of cargo traffic, directions of movement, and pace of receiving and shipping of cargo. In view of the potential scientific implementation and verification of the hypotheses about the usage of system dynamic simulation models, the goals are multi-dimensional as they include designing qualitative and quantitative simulation models for a non-linear system, verification of the validity of the behaviour dynamics of the model, application of the simulation models, application of the parameter optimisation of the simulated process, and scientific verification of the results obtained through the simulation of the model. In compliance with the developed system-dynamic, mental-verbal and structural model, using the Powersim Studio system-dynamic flowchart of the port cargo system, in Powersim Studio simulation language, it is possible to conduct a scientific research of the dynamics of the continuous behaviour of the observed port cargo system in an experimental way, i. e. by using computers, simulating various scenarios of likely occurrences in the real world, without jeopardising it. KEY WORDS: system dynamics, modelling, transhipment process, optimisation, continued and discrete simulation

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Billard, Matthew, et Thomas Kepler. « Computer simulation of lymphocyte traffic through the homeostatic lymph node (102.14) ». Journal of Immunology 186, n^o 1_Supplement (1 avril 2011) : 102.14. http://dx.doi.org/10.4049/jimmunol.186.supp.102.14.

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Abstract Lymphocytes recognize their rare cognate antigens within the complex microenvironment of secondary lymphoid organs (SLO). Proper lymphocyte migration into, through, and out of SLO is essential to immune system function and is regulated via chemotactic signals transduced through a well-known set of receptors. Specifically, CCR7, CXCR5, and S1P1 are critical lymphocyte receptors with varied expression and function depending on the lymphocyte cell type, activation state, or differentiated subtype. Our group created a flexible, modular, 3D simulation environment to investigate chemokine control of lymphocyte traffic through SLO. Simulations using computational modeling compliment and drive experimental research by performing in silico experiments that can predict outcomes and inspire new hypotheses. In our system, lymphocyte behavior is principally controlled by two models, a Langevin motility model and a chemokine receptor dynamics model. Using this simulation software, we have asked questions pertaining to the basic cell biology of lymphocytes in order to better understand the mechanisms these cells use to initiate and coordinate inflammatory responses to pathogens. This robust software platform is designed for future modification and expansion, allowing the user to replicate published data, fit models, design in silico experiments, and test new hypotheses.

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Casper, Patricia A. « A Full Mission Simulation Success Story : RPA Simulation at CSRDF Yields Promising Results ». Proceedings of the Human Factors and Ergonomics Society Annual Meeting 41, n^o 1 (octobre 1997) : 95–99. http://dx.doi.org/10.1177/107118139704100123.

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In support of the US Army's Rotorcraft Pilot's Associate Advanced Technology Demonstration Program, the Crew Station Research and Development Branch (CSRDB) at NASA's Ames Research Center has recently completed a full mission simulation (FMS) experiment testing two alternative mission equipment packages (MEPs). Four crews of Army helicopter pilots flew 64 trials, performing representative combat helicopter tasks. Objective and subjective performance metrics provided statistically significant data supporting a priori hypotheses about performance differences between the two systems. Crews flying the advanced MEP killed more targets more efficiently, and were killed fewer times than when flying the baseline MEP. In addition, their workload was lower, and subjectively assessed situation awareness was higher with the advanced system. These results are encouraging for full mission simulation research, and suggest that a standard empirical model may in fact be applicable to full mission simulation.

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Duggan, Ben, John Metzcar et Paul Macklin. « DAPT : A package enabling distributed automated parameter testing ». Gigabyte 2021 (4 juin 2021) : 1–10. http://dx.doi.org/10.46471/gigabyte.22.

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Modern agent-based models (ABM) and other simulation models require evaluation and testing of many different parameters. Managing that testing for large scale parameter sweeps (grid searches), as well as storing simulation data, requires multiple, potentially customizable steps that may vary across simulations. Furthermore, parameter testing, processing, and analysis are slowed if simulation and processing jobs cannot be shared across teammates or computational resources. While high-performance computing (HPC) has become increasingly available, models can often be tested faster with the use of multiple computers and HPC resources. To address these issues, we created the Distributed Automated Parameter Testing (DAPT) Python package. By hosting parameters in an online (and often free) “database”, multiple individuals can run parameter sets simultaneously in a distributed fashion, enabling ad hoc crowdsourcing of computational power. Combining this with a flexible, scriptable tool set, teams can evaluate models and assess their underlying hypotheses quickly. Here, we describe DAPT and provide an example demonstrating its use.

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Martínez*, A., J. Díez, P. Verde, R. Ferrero, R. Álvarez, H. Perez et A. Vizán. « Digital twin for the integration of the automatic transport and manufacturing processes ». IOP Conference Series : Materials Science and Engineering 1193, n^o 1 (1 octobre 2021) : 012107. http://dx.doi.org/10.1088/1757-899x/1193/1/012107.

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Abstract Simulation techniques for time calculation in industrial transport are not currently deterministic. This supposes a time uncertainty in production planning with economic implications. The digitization promoted by Industry 4.0 allows the automation of transport in manufacturing processes. In this way, the Automated Guided Vehicles (AGVs) performance can be simulated to obtain more accurate results. The definition of a virtual simulation environment through digital twins is an incipient area of research in this field. Digital twins achieve this purpose without intervening in the physical world thus minimising costs. In order to facilitate the use of digital twins, in this paper, we implement a web-based simulation service to improve the user experience. The user will be able to pose hypotheses and visualise the execution in real-time. The techniques implemented for the simulations are based on Robot Operating System (ROS) within the Gazebo environment, IIoT communications require the Node-network programming environment which is in charge of the hyperconnectivity and the creation of the user interface.

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Gong, Tao, James W. Minett et William S.-Y. Wang. « A simulation study on word order bias ». Interaction Studies 10, n^o 1 (24 mars 2009) : 51–75. http://dx.doi.org/10.1075/is.10.1.04gon.

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The majority of the extant languages have one of three dominant basic word orders: SVO, SOV or VSO. Various hypotheses have been proposed to explain this word order bias, including the existence of a universal grammar, the learnability imposed by cognitive constraints, the descent of modern languages from an ancestral protolanguage, and the constraints from functional principles. We run simulations using a multi-agent computational model to study this bias. Following a local order approach, the model simulates individual language processing mechanisms in production and comprehension. The simulation results demonstrate that the semantic structures that a language encodes can constrain the global syntax, and that local syntax can help trigger bias towards the global order SOV/SVO (or VOS/OVS).

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Bahé, Yannick M. « Strongly lensed cluster substructures are not in tension with ΛCDM ». Monthly Notices of the Royal Astronomical Society 505, n^o 1 (17 mai 2021) : 1458–63. http://dx.doi.org/10.1093/mnras/stab1392.

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ABSTRACT Strong gravitational lensing observations can test structure formation models by constraining the masses and concentrations of subhaloes in massive galaxy clusters. Recent work has concluded that cluster subhaloes are more abundant and/or concentrated than predicted by Λ cold dark matter (ΛCDM) simulations; this finding has been interpreted as arising from unidentified issues with simulations or an incorrect understanding of the nature of dark matter. We test these hypotheses by comparing observed subhalo masses and maximum circular velocities vmax to predictions from the high-resolution Hydrangea galaxy cluster simulation suite, which is based on the successful EAGLE galaxy formation model. Above ${\sim}10^{11}\, \mathrm{M}_\odot$, the simulated subhalo mass distribution and mass–vmax relation agrees well with observations, due to the presence of baryons during tidal stripping. Similar agreement is found for the lower resolution IllustrisTNG300 simulation. In combination, our results suggest that the abundance and concentration of cluster substructures are not in tension with ΛCDM, but may provide useful constraints for the refinement of baryon physics models in simulations.

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Gaboriau, Théo, Camille Albouy, Patrice Descombes, David Mouillot, Loïc Pellissier et Fabien Leprieur. « Ecological constraints coupled with deep-time habitat dynamics predict the latitudinal diversity gradient in reef fishes ». Proceedings of the Royal Society B : Biological Sciences 286, n^o 1911 (18 septembre 2019) : 20191506. http://dx.doi.org/10.1098/rspb.2019.1506.

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We develop a spatially explicit model of diversification based on palaeohabitat to explore the predictions of four major hypotheses potentially explaining the latitudinal diversity gradient (LDG), namely, the ‘time-area’, ‘tropical niche conservatism’, ‘ecological limits’ and ‘evolutionary speed’ hypotheses. We compare simulation outputs to observed diversity gradients in the global reef fish fauna. Our simulations show that these hypotheses are non-mutually exclusive and that their relative influence depends on the time scale considered. Simulations suggest that reef habitat dynamics produced the LDG during deep geological time, while ecological constraints shaped the modern LDG, with a strong influence of the reduction in the latitudinal extent of tropical reefs during the Neogene. Overall, this study illustrates how mechanistic models in ecology and evolution can provide a temporal and spatial understanding of the role of speciation, extinction and dispersal in generating biodiversity patterns.

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Pichugin, Yu A. « Geometrical aspects of testing the complex statistical hypotheses in mathematical simulation ». St. Petersburg State Polytechnical University Journal. Physics and Mathematics 218, n^o 2 (juin 2015) : 123–37. http://dx.doi.org/10.5862/jpm.218.13.

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Virkkunen, Juhani, et Raimo P. Hämäläinen. « Simulation analysis of some basic hypotheses about the spread of AIDS ». SIMULATION 54, n^o 1 (janvier 1990) : 21–28. http://dx.doi.org/10.1177/003754979005400104.

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Usarov, Davronbek, Kodirjon Turajonov et Saidjon Khamidov. « Simulation of free vibrations of a thick plate without simplifying hypotheses ». Journal of Physics : Conference Series 1425 (décembre 2019) : 012115. http://dx.doi.org/10.1088/1742-6596/1425/1/012115.

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bimler, david. « intimations of optimality : extensions of simulation testing of color-language hypotheses ». Behavioral and Brain Sciences 28, n^o 4 (août 2005) : 489–90. http://dx.doi.org/10.1017/s0140525x05220083.

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by emphasizing that color categories are the collective achievement of a language community, the methodology of steels & belpaeme (s&b) suggests a number of corollaries. it focuses attention on whether a system of categories is optimized to match color experience. if a hypothesis can be operationalized about the nature of the optimality – about how color language becomes standardized – it becomes testable.

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Buytaert, Wouter, et Keith Beven. « Models as multiple working hypotheses : hydrological simulation of tropical alpine wetlands ». Hydrological Processes 25, n^o 11 (3 décembre 2010) : 1784–99. http://dx.doi.org/10.1002/hyp.7936.

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Fuhrmans, Marc, et Marcus Müller. « Coarse-grained simulation of dynamin-mediated fission ». Soft Matter 11, n^o 8 (2015) : 1464–80. http://dx.doi.org/10.1039/c4sm02533d.

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We present computer simulations testing different hypotheses of how dynamin facilitates fission by constriction and curvature. Our results emphasize the importance of the local creation of a positive curvature and reveal that the topological transformation can become arrested if the proteins constituting the fission machinery are not adaptive.

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Whipple, Mark E., Anthony B. Law et Randall A. Bly. « A Computer Simulation Model to Analyze the Application Process for Competitive Residency Programs ». Journal of Graduate Medical Education 11, n^o 1 (1 février 2019) : 30–35. http://dx.doi.org/10.4300/jgme-d-18-00397.1.

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ABSTRACT Background The residency match process for competitive specialties hinders programs' ability to holistically review applications. Objective A computer simulation model of the residency application process was created to test the hypotheses that (1) it is advantageous to medical students to apply to the maximum number of programs under the current system, and (2) including a medical student's residency program preferences at the beginning of the application process improves the efficiency of the system for applicants and programs as quantified by the number of interview invitations received. Methods The study was conducted in 2016 using 2014 Otolaryngology Match data. A computer model was created to perform simulations for multiple scenarios to test the hypotheses. Students were assigned scores representing easy and hard metrics and program preferences, simulating a mixture of individual student preference and general program popularity. Results We modeled a system of 99 otolaryngology residency programs with 292 residency spots and 460 student applicants. While it was individually advantageous for an applicant to apply to the maximum number of programs, this led to a poor result for the majority of students when all applicants undertook the strategy. The number of interview invitations improved for most applicants when preference was revealed. Conclusions Offering applicants an option to provide program preference improves the practical number of interview invitations. This enables programs to review applicants holistically—instead of using single parameters such as United States Medical Licensing Examination scores—which facilitates a selection of applicants who will be successful in residency.

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Elvarsson, Bjarki Þór. « Evaluating stock structure hypotheses using genetically determined close relatives : a simulation study on North Atlantic fin whales ». ICES Journal of Marine Science 72, n^o 2 (2 juillet 2014) : 661–69. http://dx.doi.org/10.1093/icesjms/fsu140.

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Abstract Certain facets of the population dynamics of a species are hard to quantify, including stock structure. In particular, geographical boundaries of stocks or populations are often hard to estimate. This document discusses the application of a recent tagging method, applicable when breeding populations overlap on feeding grounds. The tagging efficiency is augmented with information on genetically determined close relatives. The proposed tagging method is studied using simulations. Statistics which can be used to compare rivalling stock structure hypotheses are introduced and contrasted. The simulation emulates competing stock structure hypotheses for North Atlantic fin whales (Balaenoptera physalus). The results indicate that, in the case of North Atlantic fin whales, a considerable improvement can be made in terms discriminatory power using information on close relatives when compared with more conventional tag-recapture experiments.

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Michelot, Nicolas, Pierre Carrega et Laurence Rouïl. « Panorama de la modélisation de la dispersion atmosphérique ». Pollution atmosphérique, NS 8 (1 mars 2015) : 92–100. http://dx.doi.org/10.54563/pollution-atmospherique.7885.

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Cet article présente l’éventail des possibilités techniques en matière de modélisation de la dispersion atmosphérique. Il en ressort qu’il n’est pas si facile de faire un choix parmi les modèles, malgré les grandes lignes directrices. Pour cause, sauf les rares cas d’école rodés et qui fonctionnent en routine, le traitement d’une problématique de modélisation sera perturbé par des biais parfois inévitables. C’est, par exemple, le cas d’une situation qui demande dès le départ de poser une hypothèse simplifiée, faute de données sur un type d’émissions, d’un champ de vent simulé perfectible, d’une rugosité homogène alors que les surfaces sont différentes, etc. Par conséquent, l’utilisation d’un type de modèle plutôt qu’un autre, qui plus est au sein de la même famille, n’aura que peu d’influence sur les simulations finales. Enfin, la modélisation montre qu’elle doit demeurer complémentaire à une information issue de la mesure in situ quand cela est possible, car finalement elle seule permet de rendre compte en matière de qualité de l’air réelle.

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Cadeau, Marie-Charlotte. « Hypothèse ». La revue lacanienne 4, n^o 4 (2007) : 55. http://dx.doi.org/10.3917/lrl.074.0055.

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Tuerkova, Alzbeta, et Peter M. Kasson. « Computational methods to study enveloped viral entry ». Biochemical Society Transactions 49, n^o 6 (16 novembre 2021) : 2527–37. http://dx.doi.org/10.1042/bst20210190.

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The protein–membrane interactions that mediate viral infection occur via loosely ordered, transient assemblies, creating challenges for high-resolution structure determination. Computational methods and in particular molecular dynamics simulation have thus become important adjuncts for integrating experimental data, developing mechanistic models, and suggesting testable hypotheses regarding viral function. However, the large molecular scales of virus–host interaction also create challenges for detailed molecular simulation. For this reason, continuum membrane models have played a large historical role, although they have become less favored for high-resolution models of protein assemblies and lipid organization. Here, we review recent progress in the field, with an emphasis on the insight that has been gained using a mixture of coarse-grained and atomic-resolution molecular dynamics simulations. Based on successes and challenges to date, we suggest a multiresolution strategy that should yield the best mixture of computational efficiency and physical fidelity. This strategy may facilitate further simulations of viral entry by a broader range of viruses, helping illuminate the diversity of viral entry strategies and the essential common elements that can be targeted for antiviral therapies.

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Joly, Damien O., et François Messier. « Testing hypotheses of bison population decline (1970–1999) in Wood Buffalo National Park : synergism between exotic disease and predation ». Canadian Journal of Zoology 82, n^o 7 (1 juillet 2004) : 1165–76. http://dx.doi.org/10.1139/z04-072.

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One hypothesis to explain the decline of bison (Bison bison (L., 1758)) abundance in Wood Buffalo National Park, Canada, is the "disease–predation" hypothesis where tuberculosis (Mycobacterium bovis Karlson and Lessel, 1970) and brucellosis (Brucella abortus (Schmidt, 1901)) reduce bison survival and reproduction, thus shifting bison abundance from a high-density, food-regulated equilibrium to a low-density, predator-regulated equilibrium. We use historical data on bison abundance and stochastic population simulation to examine this hypothesis. A decline in only one area of the park would discount disease as a factor, because exotic disease is present throughout the park; however, we found that decline rates were similar in the two main populations of bison. Using simulation, we found a high (68.5%) probability that a tuberculosis- and brucellosis-infected bison population experiencing predation by wolves (Canis lupus L., 1758) would stabilize at low densities (<0.83 bison/km2), which increased to 93.6% when anthrax and drowning were considered to be mortality sources. In the absence of tuberculosis and brucellosis, there was a low probability that bison would persist at this low density (<8%). These simulations suggest that an interaction between tuberculosis, brucellosis, and predation may account for the decline of bison abundance in Wood Buffalo National Park from 1970 to 1999.

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Nguyen, Trinh Quoc. « Research and development for oil spill simulation backward in time at South China Sea in Viet Nam ». Science & ; Technology Development Journal - Science of The Earth & ; Environment 1, n^o M2 (31 décembre 2017) : 23–33. http://dx.doi.org/10.32508/stdjsee.v1im2.441.

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The paper presented the evaluation of oil spill simulation backward in time with some input data conditions at South China Sea in Vietnam such as the environment factors (from simple to complex conditions) and oil spills (from one to multifarious). Oil spill processes are computed simulations such as physical processes and weathering processes and the oil properties change. The results of research and development for oil spill simulation backward in time are considered và determined with oil spill on sea that are consistent with hypotheses and natural phenomena such as reversing the direction of divergence, increased concentration backward in time, especially with an remarkable concentration area. It determines the ability to trace emission source in space and time under each corresponding input condition. Besides, this study may still not be optimized so they will continue to be solved in the future.

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Neeser, Christophe, Renán Agüero et Clarence J. Swanton. « A mechanistic model of purple nutsedge(Cyperus rotundus)population dynamics ». Weed Science 46, n^o 6 (décembre 1998) : 673–81. http://dx.doi.org/10.1017/s0043174500089700.

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We constructed a mechanistic model of purple nutsedge tuber population dynamics to provide a theoretical framework for the integrated management of this weed. The model relies on a transition matrix with 10 age classes to simulate fluctuations in the tuber population. Parameters of the transition matrix are given by functions of density, age, and cumulated incident photosynthetically active radiation (PAR) underneath crop canopies. Sensitivity ratios based on a 10% reduction in parameter values indicated that the parameters of the birthrate function were most sensitive. Simulations showed that in the absence of weed control, cumulated incident PAR was by far the strongest determinant of population size; intraspecific interference was the strongest determinant of the rate of population increase. When weed control was introduced, the simulation suggested that 95% control would be required to eliminate this weed. The analysis of simulation results led to the formulation of five research hypotheses of practical relevance to the management of purple nutsedge. New insights gained by testing these hypotheses should lead to practical recommendations as well as a better understanding of the relationships between management practices and fluctuations in purple nutsedge populations.

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Cottineau, Clémentine, Romain Reuillon, Paul Chapron, Sébastien Rey-Coyrehourcq et Denise Pumain. « A Modular Modelling Framework for Hypotheses Testing in the Simulation of Urbanisation ». Systems 3, n^o 4 (27 novembre 2015) : 348–77. http://dx.doi.org/10.3390/systems3040348.

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Cordonnier, Jean L., Robert Romanetti et Jean-Baptiste Lesourd. « On the hypotheses underlying molecular dynamics simulation models in ionic liquid systems ». Mathematical Modelling 7, n^o 1 (1986) : 83–90. http://dx.doi.org/10.1016/0270-0255(86)90122-3.

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Geonea, Ionut Daniel, Daniela Tarnita, Doina Pisla, Giuseppe Carbone, Alexandru Bolcu, Paul Tucan, Marius Georgescu et Danut Nicolae Tarniță. « Dynamic Analysis of a Spherical Parallel Robot Used for Brachial Monoparesis Rehabilitation ». Applied Sciences 11, n^o 24 (13 décembre 2021) : 11849. http://dx.doi.org/10.3390/app112411849.

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This paper presents studies on the dynamic analysis of the ASPIRE robot, which was designed for the medical recovery of brachial monoparesis. It starts from the virtual model of the existing version of the ASPIRE robot, which is analysed kinematically and dynamically by numerical simulations using the MSC.ADAMS software. For this purpose, this paper presents theoretical aspects regarding the kinematics and dynamics of the markers attached to the flexible bodies built in a specifically developed MSC.ADAMS model. Three simulation hypotheses are considered: (a) rigid kinematic elements without friction in couplings, (b) rigid kinematic elements with friction in couplings, and (c) kinematic elements as deformable solids with friction in couplings. Experimental results obtained by using the physical prototype of ASPIRE are presented. Results such as the connecting forces in the kinematic joints and the torques necessary to operate the ASPIRE robot modules have been obtained by dynamic simulation in MSC.ADAMS and compared with those determined experimentally. The comparison shows that the allure of the variation curve of the moment obtained by simulation is similar to that obtained experimentally. The difference between the maximum experimental value and that obtained by simulation is less than 1%. A finite element analysis (FEA) of the structurally optimized flexion/extension robot module is performed. The results demonstrate the operational safety of the ASPIRE robot, which is structurally capable of supporting the stresses to which it is subjected.

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Kappeler, Jürg, et Willi Gujer. « Scumming Due to Actinomycetes : An Uncalibrated Simulation Model ». Water Science and Technology 29, n^o 7 (1 avril 1994) : 285–88. http://dx.doi.org/10.2166/wst.1994.0352.

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Applications of a mathematical simulation model, which is based on a condensed summary of hypotheses related to “Scumming due to Actinomycetes”, are presented. The most important observations from practice may be simulated with the model: Substantial concentrations of hydrophobic substrate and especially non biodegradable or only slowly biodegradable surfactants may provoke a dramatic increase in the Actinomycetes population of the activated sludge.

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