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Journal articles on the topic 'Simulation'
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Gong, Weiyuan, Shuo Zhou, and Tongyang Li. "Complexity of Digital Quantum Simulation in the Low-Energy Subspace: Applications and a Lower Bound." Quantum 8 (July 15, 2024): 1409. http://dx.doi.org/10.22331/q-2024-07-15-1409.
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Digital quantum simulation has broad applications in approximating unitary evolution of Hamiltonians. In practice, many simulation tasks for quantum systems focus on quantum states in the low-energy subspace instead of the entire Hilbert space. In this paper, we systematically investigate the complexity of digital quantum simulation based on product formulas in the low-energy subspace. We show that the simulation error depends on the effective low-energy norm of the Hamiltonian for a variety of digital quantum simulation algorithms and quantum systems, allowing improvements over the previous complexities for full unitary simulations even for imperfect state preparations due to thermalization. In particular, for simulating spin models in the low-energy subspace, we prove that randomized product formulas such as qDRIFT and random permutation require smaller Trotter numbers. Such improvement also persists in symmetry-protected digital quantum simulations. We prove a similar improvement in simulating the dynamics of power-law quantum interactions. We also provide a query lower bound for general digital quantum simulations in the low-energy subspace.
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Dolag, K., S. Borgani, S. Schindler, A. Diaferio, and A. M. Bykov. "Simulation Techniques for Cosmological Simulations." Space Science Reviews 134, no. 1-4 (February 2008): 229–68. http://dx.doi.org/10.1007/s11214-008-9316-5.
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Li, Yongxing, Hongfei Jia, Ya-Nan Zhou, and Lili Yang. "Simulation research on pedestrian counter flow subconscious behavior." International Journal of Modern Physics C 28, no. 02 (February 2017): 1750025. http://dx.doi.org/10.1142/s0129183117500255.
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Analyzing the pedestrian subconscious behavior and walking environment in the passage, right-moving preference subconscious strength and overtaking subconscious strength are introduced into the pedestrian simulation model which is based on lattice gas model. Two pedestrian subconscious behavior simulation models, which are distinguished by whether considering pedestrian flow ratio of two directions or not, are established respectively. With the platform of MATLAB software, the simulations of pedestrian counter flow subconscious behavior are realized. The simulations indicate that compared with the pedestrian subconscious behavior simulation model without considering the pedestrian flow ratio of two directions, the model that considers the pedestrian flow ratio of two directions is better in simulating the pedestrian subconscious behavior.
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Pias, Claus. "On the Epistemology of Computer Simulation." ZMK Zeitschrift für Medien- und Kulturforschung 2/1/2011: Offene Objekte 2, no. 1 (2011): 29–54. http://dx.doi.org/10.28937/1000107521.
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"Der Aufsatz plädiert dafür, die Geschichte der wissenschaftlichen Computersimulation auf eine spezifisch medienhistorische Weise zu untersuchen. Nach einigen Vorschlägen zur Charakterisierung der Besonderheiten von Computersimulationen werden zwei Beispiele interpretiert (Management-Simulationen der 1960er und verkehrstechnische bzw. epidemiologische Simulationen der 1990er). Daraus leiten sich Fragen nach dem veränderten Status wissenschaftlichen Wissens, nach der Genese wissenschaftstheoretischer Konzepte und nach wissenschaftskritischen Optionen ab. </br></br>The paper suggests to analyze the history of scientific computer simulations with respect to the history of media. After presenting some ideas concerning the peculiarities of computer simulation, two examples (management simulations of the 1960s; traffic-related and epistemological simulations of the 1990s) are interpreted. From them, further questions concerning the status of scientific knowledge, the genesis of epistemological concepts and their critique are derived. "
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Greif, Hajo. "Exploring Minds: Modes of Modeling and Simulation in Artificial Intelligence." Perspectives on Science 29, no. 4 (July 2021): 409–35. http://dx.doi.org/10.1162/posc_a_00377.
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Abstract The aim of this paper is to grasp the relevant distinctions between various ways in which models and simulations in Artificial Intelligence (AI) relate to cognitive phenomena. In order to get a systematic picture, a taxonomy is developed that is based on the coordinates of formal versus material analogies and theory-guided versus pre-theoretic models in science. These distinctions have parallels in the computational versus mimetic aspects and in analytic versus exploratory types of computer simulation. The proposed taxonomy cuts across the traditional dichotomies between symbolic and embodied AI, general intelligence and symbol and intelligence and cognitive simulation and human/non-human-like AI. According to the taxonomy proposed here, one can distinguish between four distinct general approaches that figured prominently in early and classical AI, and that have partly developed into distinct research programs: first, phenomenal simulations (e.g., Turing’s “imitation game”); second, simulations that explore general-level formal isomorphisms in pursuit of a general theory of intelligence (e.g., logic-based AI); third, simulations as exploratory material models that serve to develop theoretical accounts of cognitive processes (e.g., Marr’s stages of visual processing and classical connectionism); and fourth, simulations as strictly formal models of a theory of computation that postulates cognitive processes to be isomorphic with computational processes (strong symbolic AI). In continuation of pragmatic views of the modes of modeling and simulating world affairs, this taxonomy of approaches to modeling in AI helps to elucidate how available computational concepts and simulational resources contribute to the modes of representation and theory development in AI research—and what made that research program uniquely dependent on them.
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MAHAJAN, DHIRAJ K., and SUMIT BASU. "ON THE SIMULATION OF UNIAXIAL, COMPRESSIVE BEHAVIOR OF AMORPHOUS, GLASSY POLYMERS WITH MOLECULAR DYNAMICS." International Journal of Applied Mechanics 02, no. 03 (September 2010): 515–41. http://dx.doi.org/10.1142/s1758825110000639.
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Molecular dynamics (MD) simulations offer an interesting route to simulating deformation and fracture behavior of amorphous glassy polymers. However, MD simulations are performed at extremely high rates and on very small samples (though periodic boundary conditions are routinely used) containing at most hundreds of chains which are much shorter than in real life. In this work, we try to assess the extent to which MD simulations produce physically realistic stress–strain responses and identify aspects of the simulation procedure that can be controlled closely in order to avoid numerical artifacts. We show that, when an appropriate protocol for sample generation and simulation of deformation is followed, in spite of the obvious constraints imposed by the simulation technique, MD simulations have the capability to generate realistic stress–strain curves and reproduce many experimental trends pertaining to them.
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Ritchie, Nicholas W. M. "Spectrum Simulation in DTSA-II." Microscopy and Microanalysis 15, no. 5 (September 16, 2009): 454–68. http://dx.doi.org/10.1017/s1431927609990407.
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AbstractSpectrum simulation is a useful practical and pedagogical tool. Particularly with complex samples or trace constituents, a simulation can help to understand the limits of the technique and the instrument parameters for the optimal measurement. DTSA-II, software for electron probe microanalysis, provides both easy to use and flexible tools for simulating common and less common sample geometries and materials. Analytical models based on ϕ(ρz) curves provide quick simulations of simple samples. Monte Carlo models based on electron and X-ray transport provide more sophisticated models of arbitrarily complex samples. DTSA-II provides a broad range of simulation tools in a framework with many different interchangeable physical models. In addition, DTSA-II provides tools for visualizing, comparing, manipulating, and quantifying simulated and measured spectra.
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Mueller, Patrick, Matthias Lehmann, and Alexander Braun. "Simulating tests to test simulation." Electronic Imaging 2020, no. 16 (January 26, 2020): 149–1. http://dx.doi.org/10.2352/issn.2470-1173.2020.16.avm-148.
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Simulation is an established tool to develop and validate camera systems. The goal of autonomous driving is pushing simulation into a more important and fundamental role for safety, validation and coverage of billions of miles. Realistic camera models are moving more and more into focus, as simulations need to be more then photo-realistic, they need to be physical-realistic, representing the actual camera system onboard the self-driving vehicle in all relevant physical aspects – and this is not only true for cameras, but also for radar and lidar. But when the camera simulations are becoming more and more realistic, how is this realism tested? Actual, physical camera samples are tested in laboratories following norms like ISO12233, EMVA1288 or the developing P2020, with test charts like dead leaves, slanted edge or OECF-charts. In this article we propose to validate the realism of camera simulations by simulating the physical test bench setup, and then comparing the synthetical simulation result with physical results from the real-world test bench using the established normative metrics and KPIs. While this procedure is used sporadically in industrial settings we are not aware of a rigorous presentation of these ideas in the context of realistic camera models for autonomous driving. After the description of the process we give concrete examples for several different measurement setups using MTF and SFR, and show how these can be used to characterize the quality of different camera models.
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Luo, Chenghan, Shaoping Shang, Yanshuang Xie, Zhigang He, Guomei Wei, Feng Zhang, and Lei Wang. "Evaluation of the Effect of WRF Physical Parameterizations on Typhoon and Wave Simulation in the Taiwan Strait." Water 15, no. 8 (April 13, 2023): 1526. http://dx.doi.org/10.3390/w15081526.
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Typhoons and typhoon waves can cause disasters in coastal areas around the world. The Taiwan Strait often experiences typhoons, especially in summer. Numerical models have been adopted to predict typhoons and reduce losses. The Weather Research and Forecasting (WRF) model is widely used in typhoon simulations, and the Simulating WAves Nearshore (SWAN) model performs well in wave simulations. However, significant uncertainty remains in terms of choosing suitable WRF physical parameterizations in different situations. To evaluate the effect of WRF physical parameterizations on wind and wave simulations, 27 simulation experiments were designed. Three typhoon events (Goni, Dujuan, and Meranti) with different tracks that influenced the Taiwan Strait were simulated. Three parameters (wind speed, wind direction and significant wave height) were assessed using Taylor diagrams, and it was found that the best simulation experiment changed according to typhoon tracks and physical parameters. In wind speed simulation, the best simulation experiment is 12 for typhoon Dujuan and 19 for typhoon Goni and Meranti. From the perspective of wind direction simulation, experiments 26, 23, and 2 performed best for typhoons Goni, Dujuan, and Meranti. And experiments 19, 1, and 20 had the best performances in significant wave height simulation for typhoons Goni, Dujuan, and Meranti. The WRF-SWAN model using the best simulation experiment reduced the error and exhibited good performance in the wind and wave simulations. Skill scores of three parameters were all over 70 for typhoon Goni and 80 for typhoon Dujuan and Meranti. The applicability of the best simulation experiments was demonstrated in typhoon simulations with similar tracks. The accuracy of the wave simulation depended on wind speed, wind direction, and their interaction. In addition, a scheme’s sensitivity changed with different typhoon tracks. This study provides references for designing physical parameterizations for use with the WRF-SWAN model, which may help to simulate typhoons and typhoon waves in the Taiwan Strait more accurately in the future.
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Mo, Wen Hui. "Monte Carlo Simulation of Reliability for Gear." Advanced Materials Research 268-270 (July 2011): 42–45. http://dx.doi.org/10.4028/www.scientific.net/amr.268-270.42.
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Production errors, material properties and applied loads of the gear are stochastic .Considering the influence of these stochastic factors, reliability of gear is studied. The sensitivity analysis of random variable can reduce the number of random variables. Simulating random variables, a lot of samples are generated. Using the Monte Carlo simulation based on the sensitivity analysis, reliabilities of contacting fatigue strength and bending fatigue strength can be obtained. The Monte Carlo simulation approaches the accurate solution gradually with the increase of the number of simulations. The numerical example validates the proposed method.
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Raisal, Abu Yazid, Rosynanda Nur Fauziah, and Heru Kuswanto. "SIMULATION OF FREE ENERGY OF MIXING FOR A POLYMER SOLUTION USING A SPREADSHEET FOR LEARNING ACTIVITIES." Jurnal Pendidikan Fisika 12, no. 2 (December 21, 2023): 165. http://dx.doi.org/10.24114/jpf.v12i2.52810.
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Teaching physics is sometimes difficult to convey without using props or visualizations. Simulations can help teachers create and demonstrate real conditions in front of the class. In this article, we describe the usage of spreadsheets in simulating Gibbs free energy in mixing polymer solutions. We have created an model for the simulation consisting of a main spreadsheet and several secondary spreadsheets. A spreadsheet was chosen to simulate Gibbs free energy because spreadsheets can perform numerical representations in tables. This simple simulation can be used when discussing the topic of polymer thermodynamics. Teachers can start by deriving mathematical equations and then show simulations to visualize the equations. Another option is for students to be asked to create their simulations after deriving a mathematical equation. Using simulation in learning can make learning more interactive and help students understand material physics subjects more easily. Spreadsheets can be an alternative for teachers when explaining abstract material to students. Furthermore, simulations with spreadsheets can also support physics learning remotely.
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Grafton, Carl, and Anne Permaloff. "Microcomputer Simulations and Simulation Writing Tools." PS: Political Science and Politics 22, no. 2 (June 1989): 247. http://dx.doi.org/10.2307/419603.
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Grafton, Carl, and Anne Permaloff. "Microcomputer Simulations and Simulation Writing Tools." PS: Political Science & Politics 22, no. 02 (June 1989): 247–57. http://dx.doi.org/10.1017/s1049096500030560.
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Wu, Qing, Maksym Spiryagin, Ingemar Persson, Chris Bosomworth, and Colin Cole. "Parallel computing of wheel-rail contact." Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 234, no. 10 (October 8, 2019): 1109–16. http://dx.doi.org/10.1177/0954409719880737.
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Railway wheel–rail contact simulations are the most important and time-consuming tasks when simulating the system dynamics of vehicles. Parallel computing is a good approach for improving the numerical computing speed. This paper reports the advances in parallel computing of the wheel–rail contact simulations. The proposed method uses OpenMP to parallelise the multiple contact points of all the wheel–rail interfaces of a locomotive model. The method has been implemented in the vehicle system dynamics simulation package GENSYS. Simulations were conducted using two numerical solvers (4th Runge-Kutta and HeunC) and a maximum of four computer cores. Simulation cases have shown exactly the same numerical results using serial computing and parallel computing, which prove the effectiveness of the parallel computing method. The HeunC solver achieved the same simulation results and is 3.5 times faster than the 4th Runge-Kutta method. Simulation results obtained from both numerical solvers show that parallel computing using 2, 3 and 4 computer cores can improve the simulation speeds by roughly 29, 39 and 41%, respectively. There is an apparent diminishing of the rate of improvement due to the increase of the communication resource overhead when more computer cores are used. Using up to four computer cores does not require revision of the GENSYS code, and simulations can be executed using personal computers.
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Słodkowski, Marcin, Patryk Gawryszewski, Patryk Marcinkowski, Dominik Setniewski, and Joanna Porter-Sobieraj. "Simulations of Energy Losses in the Bulk Nuclear Medium Using Hydrodynamics on the Graphics Cards (GPU)." Proceedings 10, no. 1 (April 15, 2019): 27. http://dx.doi.org/10.3390/proceedings2019010027.
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We are developing a software for energy loss simulation which is affected by jets in the nuclear matter described by relativistic hydrodynamics. Our program uses a Cartesian coordinate system in order to provide high spatial resolution for the analysis of jets propagation in nuclear matter. In this work, we use 7th order WENO numerical algorithm which is resistant to numerical oscillations and diffusions. For simulating energy losses in the bulk nuclear medium, we develop efficient hydrodynamic simulation program for parallel computing using Graphics Processing Unit (GPU) and Compute Unified Device Architecture (CUDA). It allows us to prepare event-by-event simulations in high computing precision in order to study jet modifications in the medium and event-by-event simulations of fluctuating initial conditions. In our simulation, we start the hydrodynamic simulation from generation initial condition based on the UrQMD model in order to simulate comparable nucleus-nucleus interaction in the RHIC and LHC energies. The main part of this simulation is the computation of hydrodynamic system evolution. We present obtained energy density distributions which can be compared to experimental results.
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YI, H. H., L. J. FAN, and Y. Y. CHEN. "LATTICE BOLTZMANN SIMULATION OF THE MOTION OF SPHERICAL PARTICLES IN STEADY POISEUILLE FLOW." International Journal of Modern Physics C 20, no. 06 (June 2009): 831–46. http://dx.doi.org/10.1142/s0129183109014035.
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A technique, based on the stress-integration method, for the evaluation of hydrodynamic forces on solid boundaries is proposed to simulate the solid-fluid flow systems in three dimensions in lattice Boltzmann simulations. The accuracy of the scheme is demonstrated by simulating the sphere migrating in a pressure-driven Newtonian fluid flow in a cylindrical tube. The numerical simulation results recover the Segré–Silberberg effect. Using this scheme, we investigate the behavior of a pair of spheres in a tube Poiseuille flow. Oscillatory states are observed for two spheres with different radii placed on opposite sides. The simulation results show that the present model is an effective and efficient direct numerical simulation method for simulating particle motions in fluid flows at finite Reynolds numbers in three dimensions.
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Spannagel, S., and P. Schütze. "Allpix2 — silicon detector Monte Carlo simulations for particle physics and beyond." Journal of Instrumentation 17, no. 09 (September 1, 2022): C09024. http://dx.doi.org/10.1088/1748-0221/17/09/c09024.
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Abstract Allpix2 is a versatile, open-source simulation framework for silicon pixel detectors. Its goal is to ease the implementation of detailed simulations for both single sensors and more complex setups with multiple detectors. While originally created for silicon detectors in high-energy physics, it is capable of simulating a wide range of detector types for various application scenarios, through its interface to Geant4 to describe the interaction of particles with matter, and the different algorithms for charge transport and digitization. The simulation chain is arranged with the help of intuitive configuration files and an extensible system of modules, which implement the individual simulation steps. Detailed electric field maps imported from TCAD simulations can be used to precisely model the drift behavior of the charge carriers, bringing a new level of realism to the Monte Carlo simulation of particle detectors. Recently, Allpix2 has seen major improvements to its core framework to take full advantage of multi- and many-core processor architectures for simulating events fully parallel. Furthermore, new physics models such as charge carrier recombination in silicon have been introduced, further extending the application range. This contribution provides an overview of the framework and its components, highlighting the versatility and recent developments.
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Liu, Youjun, Wei Huang, Haiwen Zhu, Song Gao, and Yue Diao. "SIMULATION OF HEMODYNAMICS IN ABDOMINAL AORTA(Cardiovascular flow Simulation)." Proceedings of the Asian Pacific Conference on Biomechanics : emerging science and technology in biomechanics 2004.1 (2004): 49–50. http://dx.doi.org/10.1299/jsmeapbio.2004.1.49.
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Wu, Yongxing, Fei Peng, Yang Peng, Xiaoyang Kong, Heming Liang, and Qi Li. "Dynamic 3D Simulation of Flood Risk Based on the Integration of Spatio-Temporal GIS and Hydrodynamic Models." ISPRS International Journal of Geo-Information 8, no. 11 (November 18, 2019): 520. http://dx.doi.org/10.3390/ijgi8110520.
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Dynamic visual simulation of flood risk is crucial for scientific and intelligent emergency management of flood disasters, in which data quality, availability, visualization, and interoperability are important. Here, a seamless integration of a spatio-temporal Geographic Information System (GIS) with one-dimensional (1D) and two-dimensional (2D) hydrodynamic models is achieved for data flow, calculation processes, operation flow, and system functions. Oblique photography-based three-dimensional (3D) modeling technology is used to quickly build a 3D model of the study area (including the hydraulic engineering facilities). A multisource spatio-temporal data platform for dynamically simulating flood risk was built based on the digital earth platform. Using the spatio-temporal computation framework, a dynamic visual simulation and decision support system for flood risk management was developed for the Xiashan Reservoir. The integration method proposed here was verified using flood simulation calculations, dynamic visual simulations, and downstream river channel and dam-break flood simulations. The results show that the proposed methods greatly improve the efficiency of flood risk simulation and decision support. The methods and system put forward in this study can be applied to flood risk simulations and practical management.
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Steinmetz, Janina, Brittany M. Tausen, and Jane L. Risen. "Mental Simulation of Visceral States Affects Preferences and Behavior." Personality and Social Psychology Bulletin 44, no. 3 (November 21, 2017): 406–17. http://dx.doi.org/10.1177/0146167217741315.
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Preferences and behavior are heavily influenced by one’s current visceral experience, yet people often fail to anticipate such effects. Although research suggests that this gap is difficult to overcome—to act as if in another visceral state—research on mental simulation has demonstrated that simulations can substitute for experiences, albeit to a weaker extent. We examine whether mentally simulating visceral states can impact preferences and behavior. We show that simulating a specific visceral state (e.g., being cold or hungry) shifts people’s preferences for relevant activities (Studies 1a-2) and choices of food portion sizes (Study 3). Like actual visceral experiences, mental simulation only affects people’s current preferences but not their general preferences (Study 4). Finally, people project simulated states onto similar others, as is the case for actual visceral experiences (Study 5). Thus, mental simulation may help people anticipate their own and others’ future preferences, thereby improving their decision making.
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FERNÁNDEZ-ZEPEDA, JOSÉ ALBERTO, DANIEL FAJARDO-DELGADO, JOSÉ ANTONIO CÁRDENAS-HARO, and ANU G. BOURGEOIS. "EFFICIENT SIMULATION OF AN ACYCLIC DIRECTED RECONFIGURABLE MODEL ON AN UNDIRECTED RECONFIGURABLE MODEL." International Journal of Foundations of Computer Science 16, no. 01 (February 2005): 55–70. http://dx.doi.org/10.1142/s0129054105002863.
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In this paper we present a simulation of an acyclic n×n DR-Mesh on an n×n LR-Mesh. The simulation is efficient in regards to size since both models use the same number of processors. The worst execution time for this simulation is O(n2) time, but we demonstrate that its average execution time is O( log n). The fastest existing simulation takes O( log n) time, but it uses an extremely large number of processors. On the other hand, the most efficient simulation in terms of size takes O( log 2n) time with O(n4/ log 2n) processors. Both of the existing simulations are for the unrestricted DR-Mesh. This paper provides an important step towards efficiently simulating the unrestricted DR-Mesh on weaker models such as the R-Mesh and the LR-Mesh.
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Kohn, Oliver, Julius Frenzel, Erkut Sarikaya, and Matthias Weigold. "Virtuelle Prozesssimulation einer CNC-Maschine/Virtual process simulation of a CNC machine – Digital twin for stress-based payment models." wt Werkstattstechnik online 113, no. 01-02 (2023): 24–28. http://dx.doi.org/10.37544/1436-4980-2023-01-02-28.
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Innovative Ansätze bei der Prozessplanung und -optimierung mittels digitaler Zwillinge erfordern leistungsfähige Simulationen für Werkzeugmaschinen. Die Entwicklung einer solchen Simulation für ein 3-Achs-Vertikal-Bearbeitungszentrum wird hier als hybride Multi-Domain-Simulation in „Modelica“ implementiert und experimentell validiert. Dabei ist das Ziel die berechneten Kenngrößen im Kontext aktueller Entwicklungen, wie zum Beispiel belastungsorientierter Bezahlmodelle bereitzustellen. Innovative approaches to process planning and optimization using digital twins require powerful simulations for machine tools. The development of such a simulation for a 3-axis vertical machining center is presented here. The hybrid multi-domain simulation is implemented in ‚Modelica‘ and validated experimentally. The aim is to provide the calculated parameters in the context of current developments such as load-oriented payment models.
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Hayato, Yoshinari, and Luke Pickering. "The NEUT neutrino interaction simulation program library." European Physical Journal Special Topics 230, no. 24 (October 11, 2021): 4469–81. http://dx.doi.org/10.1140/epjs/s11734-021-00287-7.
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Abstract is a neutrino–nucleus interaction simulation program library. It can be used to simulate interactions for neutrinos with between 100 MeV and a few TeV of energy. is also capable of simulating hadron interactions within a nucleus and is used to model nucleon decay and hadron–nucleus interactions for particle propagation in detector simulations. This article describes the range of interactions modelled and how each is implemented.
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Çakmak, Hüseyin, Anselm Erdmann, Michael Kyesswa, Uwe Kühnapfel, and Veit Hagenmeyer. "A new distributed co-simulation architecture for multi-physics based energy systems integration." at - Automatisierungstechnik 67, no. 11 (November 26, 2019): 972–83. http://dx.doi.org/10.1515/auto-2019-0081.
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Abstract Simulating energy systems integration scenarios enables a comprehensive consideration of interdependencies between multimodal energy grids. It is an important part of the planning for the redesign of the current energy system infrastructure, which is essential for the foreseen drastic reduction of carbon emissions. In contrast to the complex implementation of monolithic simulation architectures, emerging distributed co-simulation technologies enable the combination of several existing single-domain simulations into one large energy systems integration simulation. Accompanying disadvantages of coupling simulators have to be minimized by an appropriate co-simulation architecture. Hence, in the present paper, a new simulation architecture for energy systems integration co-simulation is introduced, which enables an easy and fast handling of the therefore required simulation setup. The performance of the new distributed co-simulation architecture for energy systems integration is shown by a campus grid scenario with a focus on the effects of power to gas and the reversal process onto the electricity grid. The implemented control strategy enables a successful co-simulation of electrolysis coupled with photovoltaics, a hydrogen storage with a combined heat and power plant and a variable power consumption.
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Vasileva, Svetlana, and Aleksandar Milev. "Simulation Studies of Distributed Two-phase Locking in Distributed Database Management Systems." Information Technologies and Control 13, no. 1-2 (June 1, 2015): 46–55. http://dx.doi.org/10.1515/itc-2016-0010.
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Abstract This paper considers algorithms simulating the implementation of distributed two-phase locking (2PL) protocols in distributed database systems and simulation results. It describes specifically the simulations of two-version 2PL and 2PL with integrated timestamp ordering mechanism. Integrated modelling algorithms for deadlock avoiding are suggested in the paper: twoversion architecture of database and timestamp ordering strategy “wait-die”. The results of the simulations of these two variants of the 2PL method at different scales of the networks for data transmission and at different intensities of inflow transactions are also presented. Modelling algorithms are developed by means of the system for simulation modelling GPSS World Personal Version.
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Ji, Qiuyan, Feilong Han, Wei Qian, Qing Guo, and Shulin Wan. "A machine learning-driven stochastic simulation of underground sulfide distribution with multiple constraints." Open Geosciences 13, no. 1 (January 1, 2021): 807–19. http://dx.doi.org/10.1515/geo-2020-0274.
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Abstract The increase of sulfide (S2−) during the water flooding process has been regarded as an essential and potential risk for oilfield development and safety. Kriging and stochastic simulations are common methods for assessing the element distribution. However, these traditional simulation methods are not able to predict the continuous changes of underground S2− distribution in the time domain by limited known information directly. This study is a kind of attempt to combine stochastic simulation and the modified probabilistic neural network (modified PNN) for simulating short-term changes of S2− concentration. The proposed modified PNN constructs the connection between multiple indirect datasets and S2− concentration at sampling points. These connections, which are treated as indirect data in the stochastic simulation processes, is able to provide extra supports for changing the probability density function (PDF) and enhancing the stability of the simulation. In addition, the simulation process can be controlled by multiple constraints due to which the simulating target has been changed into the increment distribution of S2−. The actual data test provides S2− distributions in an oil field with good continuity and accuracy, which demonstrate the outstanding capability of this novel method.
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Flo, Jill. "Simulation in nursing students’ preclinical studies — Does the timing of the simulation matter?" Journal of Nursing Education and Practice 11, no. 12 (July 29, 2021): 10. http://dx.doi.org/10.5430/jnep.v11n12p10.
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Background: A descriptive case study evaluated second-year undergraduate nursing students’ perception of simulations, comparing two curricula.Methods: Questionnaires were completed post-simulation by 658 students from the classes of 2013/2014 (old curriculum) and the class of 2015 (new curriculum).Results: The classes of 2013/2014 were more satisfied with the written information than the class of 2015 (mean of 3.83 vs 3.32, p < .001). The classes of 2013/2014 were also better prepared (mean of 3.44 vs 3.12, p < .001). A significant difference was found between the classes of 2013/2014 and 2015 regarding the benefit of the simulation (mean of 3.94 vs 4.16, p < .001). Moreover, the surgical group found simulating with the manikin more beneficial compared to the medical and mental health groups’ experience with role-play (mean of 4.33 vs 4.08 vs 4.11, p < .050). Finally, male students reported simulation as more beneficial than female students (mean of 4.30 vs 4.01, p < .005).Conclusions: Between-class differences emerged when the curriculum changed, and students found simulation with a manikin directly before clinical practice most beneficial.
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Zhang, Yongqiang, Jianxiong Zhou, Zhiyong Song, and Kaixin Zhou. "High-Precision GPU-Accelerated Simulation Algorithm for Targets under Non-Uniform Cluttered Backgrounds." Remote Sensing 15, no. 19 (September 22, 2023): 4664. http://dx.doi.org/10.3390/rs15194664.
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This article presents a high-precision airborne video synthetic aperture radar (SAR) raw echo simulation method aimed at addressing the issue of simulation accuracy in video SAR image generation. The proposed method employs separate techniques for simulating targets and ground clutter, utilizing pre-existing SAR images for clutter simulation and employing the shooting and bouncing rays (SBR) approach to generate target echoes. Additionally, the method accounts for target-generated shadows to enhance the realism of the simulation results. The fast simulation algorithm is implemented using the C++ programming language and the Accelerated Massive Parallelism (AMP) framework, providing a fusion technique for integrating clutter and target simulations. By combining the two types of simulated data to form the final SAR image, the method achieves efficient and accurate simulation technology. Experimental results demonstrate that this method not only improves computational speed but also ensures the accuracy and stability of the simulation outcomes. This research holds significant implications for the development of algorithms pertaining to video SAR target detection and tracking, providing robust support for practical applications.
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Chen, Liang, and Richard F. Serfozo. "Performance limitations of parallel simulations." Journal of Applied Mathematics and Stochastic Analysis 11, no. 3 (January 1, 1998): 397–409. http://dx.doi.org/10.1155/s1048953398000331.
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This study shows how the performance of a parallel simulation may be affected by the structure of the system being simulated. We consider a wide class of linearly synchronous simulations consisting of asynchronous and synchronous parallel simulations (or other distributed-processing systems), with conservative or optimistic protocols, in which the differences in the virtual times of the logical processes being simulated in real time t are of the order o(t) as t tends to infinity. Using a random time transformation idea, we show how a simulation's processing rate in real time is related to the throughput rates in virtual time of the system being simulated. This relation is the basis for establishing upper bounds on simulation processing rates. The bounds for the rates are tight and are close to the actual rates as numerical experiments indicate. We use the bounds to determine the maximum number of processors that a simulation can effectively use. The bounds also give insight into efficient assignment of processors to the logical processes in a simulation.
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Botsis, T., R. Ball, and J. Scott. "Simulating adverse event spontaneous reporting systems as preferential attachment networks." Applied Clinical Informatics 05, no. 01 (2014): 206–18. http://dx.doi.org/10.4338/aci-2013-11-ra-0097.
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SummaryBackground: Spontaneous Reporting Systems [SRS] are critical tools in the post-licensure evaluation of medical product safety. Regulatory authorities use a variety of data mining techniques to detect potential safety signals in SRS databases. Assessing the performance of such signal detection procedures requires simulated SRS databases, but simulation strategies proposed to date each have limitations.Objective: We sought to develop a novel SRS simulation strategy based on plausible mechanisms for the growth of databases over time.Methods: We developed a simulation strategy based on the network principle of preferential attachment. We demonstrated how this strategy can be used to create simulations based on specific databases of interest, and provided an example of using such simulations to compare signal detection thresholds for a popular data mining algorithm.Results: The preferential attachment simulations were generally structurally similar to our targeted SRS database, although they had fewer nodes of very high degree. The approach was able to generate signal-free SRS simulations, as well as mimicking specific known true signals. Explorations of different reporting thresholds for the FDA Vaccine Adverse Event Reporting System suggested that using proportional reporting ratio [PRR] > 3.0 may yield better signal detection operating characteristics than the more commonly used PRR > 2.0 threshold.Discussion: The network analytic approach to SRS simulation based on the principle of preferential attachment provides an attractive framework for exploring the performance of safety signal detection algorithms. This approach is potentially more principled and versatile than existing simulation approaches.Conclusion: The utility of network-based SRS simulations needs to be further explored by evaluating other types of simulated signals with a broader range of data mining approaches, and comparing network-based simulations with other simulation strategies where applicable.Citation: Scott J, Botsis T, Ball R. Simulating adverse event spontaneous reporting systems as preferential attachment networks: Application to the Vaccine Adverse Event Reporting System. Appl Clin Inf 2014; 5: 206–218 http://dx.doi.org/10.4338/ACI-2013-11-RA-0097
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Szynkiewicz, Paweł. "A Novel GPU-Enabled Simulator for Large Scale Spiking Neural Networks." Journal of Telecommunications and Information Technology, no. 2 (June 30, 2016): 34–42. http://dx.doi.org/10.26636/jtit.2016.2.717.
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The understanding of the structural and dynamic complexity of neural networks is greatly facilitated by computer simulations. An ongoing challenge for simulating realistic models is, however, computational speed. In this paper a framework for modeling and parallel simulation of biological-inspired large scale spiking neural networks on high-performance graphics processors is described. This tool is implemented in the OpenCL programming technology. It enables simulation study with three models: Integrate-andfire, Hodgkin-Huxley and Izhikevich neuron model. The results of extensive simulations are provided to illustrate the operation and performance of the presented software framework. The particular attention is focused on the computational speed-up factor.
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Zhang, Shengjie. "The application and algorithm of fabric simulation in game industry." Applied and Computational Engineering 67, no. 1 (July 16, 2024): 78–88. http://dx.doi.org/10.54254/2755-2721/78/20240638.
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fabric simulation has emerged as a crucial aspect of computer graphics, particularly in applications such as film production, video games, and design. This paper provides a comprehensive review of fabric simulation methodologies, implementation techniques, and its diverse applications within the game industry. The fabric simulation algorithms are broken down into Fabric Modeling, Dynamic Simulation, and Collision Handling. The three common modeling strategies of Elasticity-Based Models, Particle-Based Models, and Mass-Spring Damper Models, are discussed in detail. Additionally, dynamic simulation strategies such as Position-Based Dynamics (PBD) and Extended Position-Based Dynamics (XPBD) are explored for their role in real-time simulations, particularly in the game industry. The paper also delves into collision handling algorithms, exploring the strategies for accurate collision detection and response. The application of fabric simulation in the game industry is highlighted, showcasing how it enhances realism and immersion by simulating fabric movement and interactions with the environment. The paper introduced various fabric simulation tools and systems within popular game engines like Unity 3D and Unreal Engine 5. Furthermore, optimization strategies, such as view-dependent adaptive simulation, are discussed to improve performance providing insight for future work.
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Zhang, Shengjie. "The application and algorithm of fabric simulation in game industry." Applied and Computational Engineering 67, no. 1 (July 16, 2024): 78–88. http://dx.doi.org/10.54254/2755-2721/67/20240638.
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fabric simulation has emerged as a crucial aspect of computer graphics, particularly in applications such as film production, video games, and design. This paper provides a comprehensive review of fabric simulation methodologies, implementation techniques, and its diverse applications within the game industry. The fabric simulation algorithms are broken down into Fabric Modeling, Dynamic Simulation, and Collision Handling. The three common modeling strategies of Elasticity-Based Models, Particle-Based Models, and Mass-Spring Damper Models, are discussed in detail. Additionally, dynamic simulation strategies such as Position-Based Dynamics (PBD) and Extended Position-Based Dynamics (XPBD) are explored for their role in real-time simulations, particularly in the game industry. The paper also delves into collision handling algorithms, exploring the strategies for accurate collision detection and response. The application of fabric simulation in the game industry is highlighted, showcasing how it enhances realism and immersion by simulating fabric movement and interactions with the environment. The paper introduced various fabric simulation tools and systems within popular game engines like Unity 3D and Unreal Engine 5. Furthermore, optimization strategies, such as view-dependent adaptive simulation, are discussed to improve performance providing insight for future work.
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Blanchard, Erin E., Sue S. Feldman, Marjorie Lee White, Ryan Allen, Thad Phillips, and Michelle R. Brown. "Design and Implementation of Tabletop Cybersecurity Simulation for Health Informatics Graduate Students." Applied Clinical Informatics 15, no. 05 (October 2024): 921–27. http://dx.doi.org/10.1055/s-0044-1790551.
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Abstract Background Experiential learning through simulation allows students to apply didactic knowledge to real-world situations. Tabletop simulation allows for the exploration of a variety of topics, including cybersecurity in health care. Due to its low frequency, yet high-risk nature, simulation is a perfect educational modality to practice responding to a cybersecurity attack. As such, the authors designed and executed a tabletop cybersecurity simulation consisting of a prebriefing, four rounds of injects detailing potential cybersecurity breaches that students must address, and structured debriefings that included input from cybersecurity content experts. This simulation was performed in 2018, 2019, 2022, and 2023, during graduate Health Informatics (HI) students' residential visits. Objective The simulation allowed opportunities for HI students to apply knowledge of cybersecurity principles to an unfolding tabletop simulation containing injects of scenarios they may encounter in the real world. Methods Survey data were used to assess the students' perceptions of the simulation. Topics assessed included overall satisfaction, teamwork and communication, and length of the event. Additionally, in 2022 and 2023, data were collected on psychological safety and whether to include them in future HI residential visits. Results Eighty-eight graduate HI students took part in the cybersecurity simulation over four annual residential visits. Most students were satisfied with the event, found it valuable, and could see it impacting their future practice as informaticists. Additionally, students indicated high levels of psychological safety. Multiple students requested that additional simulations be incorporated into the curriculum. Conclusion A tabletop cybersecurity simulation was utilized to allow HI students the ability to apply knowledge related to cybersecurity breaches to real-world examples. The simulation's best practices of prebriefing, psychological safety, and structured debriefing with expert feedback were emphasized in the simulation's design and implementation. Students found the simulation valuable and worth including in the curriculum.
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Berry, Dominic W., Andrew M. Childs, Yuan Su, Xin Wang, and Nathan Wiebe. "Time-dependent Hamiltonian simulation with L1-norm scaling." Quantum 4 (April 20, 2020): 254. http://dx.doi.org/10.22331/q-2020-04-20-254.
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The difficulty of simulating quantum dynamics depends on the norm of the Hamiltonian. When the Hamiltonian varies with time, the simulation complexity should only depend on this quantity instantaneously. We develop quantum simulation algorithms that exploit this intuition. For sparse Hamiltonian simulation, the gate complexity scales with the L1 norm ∫0tdτ‖H(τ)‖max, whereas the best previous results scale with tmaxτ∈[0,t]‖H(τ)‖max. We also show analogous results for Hamiltonians that are linear combinations of unitaries. Our approaches thus provide an improvement over previous simulation algorithms that can be substantial when the Hamiltonian varies significantly. We introduce two new techniques: a classical sampler of time-dependent Hamiltonians and a rescaling principle for the Schrödinger equation. The rescaled Dyson-series algorithm is nearly optimal with respect to all parameters of interest, whereas the sampling-based approach is easier to realize for near-term simulation. These algorithms could potentially be applied to semi-classical simulations of scattering processes in quantum chemistry.
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Janíček, František, Martin Mucha, Karol Česnek, and Jozef Kováčik. "Controlled Switching of the T402 Transformer in the Križovany 400kV Substation." Journal of Electrical Engineering 61, no. 1 (January 1, 2010): 11–19. http://dx.doi.org/10.2478/v10187-010-0002-y.
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Controlled Switching of the T402 Transformer in the Križovany 400kV Substation The paper deals with simulating the circumstances of switching surge and trigger current at switching-in of the T402 autotransformer recently installed in Križovany, with the tests conducted by means of ATP (Alternative Transient Program) simulation software for simulating transient electromagnetic phenomena. The target has been to determine temporal curves for the most critical surge instances against earth and between the phases and the curves for trigger current with and without surge limiters connected, and to determine by means of simulations the size and statistical frequency of switching surges and based on a controlled switching simulation, to describe the elimination of transient phenomena during the process and in reference to the simulations and to operating manual for the PSD02 Siemens control unit, suggest the required configuration settings for the unit.
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Celik, Nurcin, Esfandyar Mazhari, John Canby, Omid Kazemi, Parag Sarfare, Majed S. Al-Otaibi, and Young-Jun Son. "Automatic Partitioning of Large Scale Simulation in Grid Computing for Run Time Reduction." International Journal of Operations Research and Information Systems 1, no. 2 (April 2010): 64–90. http://dx.doi.org/10.4018/joris.2010040105.
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Simulating large-scale systems usually entails exhaustive computational powers and lengthy execution times. The goal of this research is to reduce execution time of large-scale simulations without sacrificing their accuracy by partitioning a monolithic model into multiple pieces automatically and executing them in a distributed computing environment. While this partitioning allows us to distribute required computational power to multiple computers, it creates a new challenge of synchronizing the partitioned models. In this article, a partitioning methodology based on a modified Prim’s algorithm is proposed to minimize the overall simulation execution time considering 1) internal computation in each of the partitioned models and 2) time synchronization between them. In addition, the authors seek to find the most advantageous number of partitioned models from the monolithic model by evaluating the tradeoff between reduced computations vs. increased time synchronization requirements. In this article, epoch- based synchronization is employed to synchronize logical times of the partitioned simulations, where an appropriate time interval is determined based on the off-line simulation analyses. A computational grid framework is employed for execution of the simulations partitioned by the proposed methodology. The experimental results reveal that the proposed approach reduces simulation execution time significantly while maintaining the accuracy as compared with the monolithic simulation execution approach.
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Kindler, Eugene. "Simulation of Systems with Simulating Components." IFAC Proceedings Volumes 33, no. 17 (July 2000): 525–30. http://dx.doi.org/10.1016/s1474-6670(17)39457-0.
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Whitlock, B. K., J. J. Morikuni, E. Conforti, and Sung-Mo Kang. "Simulation and modeling: simulating optical interconnects." IEEE Circuits and Devices Magazine 11, no. 3 (May 1995): 12–18. http://dx.doi.org/10.1109/101.385721.
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Santos, Rômulo Damasclin Chaves dos, and Jorge Henrique de Oliveira Sales. "Mathematical analysis for simulation of incompressible fluid flow." Journal of Engineering and Exact Sciences 9, no. 12 (December 5, 2023): 17392. http://dx.doi.org/10.18540/jcecvl9iss12pp17392.
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The omnipresence and complexity of physical phenomena drive the strong search for tools capable of simulating them, since many applications require computationally viable, reliable and, preferably, low-cost simulations. Thus, a priori, this work has two objectives: i) understand the theoretical foundations of fluid dynamics with an important computational method aimed at simulating incompressible flows, called SPH (Smoothed Particle Hydrodynamic), which will subsequently be implemented; and ii) assist in the consolidation and application of key concepts in mathematical analysis for computer simulation. Our efforts in this work provide mathematical foundations, which in turn, describe the dynamics of fluid dynamic motion.
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Raad, Vanda Abi. "HOW TO IMPLEMENT SIMULATION BASED EDUCATION IN A NEW MEDICAL SCHOOL." BMJ Simulation and Technology Enhanced Learning 1, no. 1 (May 13, 2015): 42.1–42. http://dx.doi.org/10.1136/bmjstel-2015-000044.4.
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BackgroundSimulation based Education has become an integral part of medical education from undergraduate to postgraduate levels.Summary of workThe integration of simulation into a medical curriculum requires informed implementation in ways that take advantage of simulation's unique ability to facilitate guided application of new knowledge. Simulation offers an experiential learning environment that is ideally suited to the goal-directed learning needed in undergraduate and postgraduate education. Various types of curricula might be developed such as cognitive, communication and procedural skills. Also, a broad range of simulation methodologies can be employed to service the specific educational programs. Part-task trainers, mannequin-based simulation, virtual reality, in-situ techniques, hybrid configurations, screen-based simulations and encounters with ‘standardized’ patients, nurses or physician colleagues all can play a role in the anaesthesia curriculum. Determining which components of a curriculum are enhanced using simulation-based education, and incorporating the exercises into the existing model, result in more goal directed and sustained use of the tool.Summary of resultsExamples of the integration of simulation based education in the undergraduate and postgraduate curriculum at the Lebanese American University-School of Medicine will be discussed.ConclusionsTo optimize both the learning and assessment experience of simulation, educators should remember the principles of effective simulation, the advantages/disadvantages of simulation as well as the goals-tools match.
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Takayesu, James K., Eric S. Nadel, Kriti Bhatia, and Ron M. Walls. "Incorporating simulation into a residency curriculum." CJEM 12, no. 04 (July 2010): 349–53. http://dx.doi.org/10.1017/s1481803500012458.
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ABSTRACT The integration of simulation into a medical postgraduate curriculum requires informed implementation in ways that take advantage of simulation's unique ability to facilitate guided application of new knowledge. It requires review of all objectives of the training program to ensure that each of these is mapped to the best possible learning method. To take maximum advantage of the training enhancements made possible by medical simulation, it must be integrated into the learning environment, not simply added on. This requires extensive reorganization of the resident didactic schedule. Simulation planning is supported by clear learning objectives that define the goals of the session, promote learner investment in active participation and allow for structured feedback for individual growth. Teaching to specific objectives using simulation requires an increased time commitment from teaching faculty and careful logistical planning to facilitate flow of learners through a series of simulations in ways that maximize learning. When applied appropriately, simulation offers a unique opportunity for learners to acquire and apply new knowledge under direct supervision in ways that complement the rest of the educational curriculum. In addition, simulation can improve the learning environment and morale of residents, provide additional methods of resident evaluation, and facilitate the introduction of new technologies and procedures into the clinical environment.
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Tamura, Tomoyuki, Ryota Odagaki, Yusuke Kishita, Yasushi Umeda, Gaku Miyake, Genichiro Matsuda, and Akio Tajima. "A Method for Simulating an Information System with Life Cycle Simulation." International Journal of Automation Technology 18, no. 6 (November 5, 2024): 774–85. http://dx.doi.org/10.20965/ijat.2024.p0774.
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Given the rapid growth of digital technologies, the use of information systems (ISs) is increasingly important for businesses positioned within the circular economy (CE). When designing an IS for such businesses, it is essential to simulate how the IS affects the life cycle (LC). However, existing research has not yet addressed this issue. For example, life cycle simulation (LCS) mods an LC and evaluates the economic profit and environmental impact of a product across its entire LC but does not explicitly model the IS and the effect from IS on LC is not simulated clearly. In this study, we propose a modeling method (E-DFD) and a simulation system (ISS) for modeling and simulating the IS. In the E-DFD and the ISS, we model and simulate an IS as a set of functions. Additionally, we propose a method that facilitates cooperation between IS simulations and LC simulations, allowing the effect of IS functions on LC to be evaluated. To validate the effectiveness of the ISS and the simulation method, we describe a case study that targets a new servitized business model with refrigerators. In the case study, we considered three patterns of LCs and two IS patterns with different functions for comparing the entire LCs and how the economic profit and environmental impact are changed depending on the difference in IS functions. In this case study, the IS and LC simulations identify how differences in IS functions affect the economic service provider’s profit, as well as the CO2 emission from the entire LC. Although our simulation method covers the entire LC, the functions of the IS focused on the use process in the case study. Therefore, further case studies targeting the LC processes, except the use process, are important for future work. In addition, developing methods for modeling and simulating the economic and environmental aspects of an IS is required.
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Thatcher, Donald C., and M. June Robinson. "A Simulation on the Design of Simulations." Simulation & Gaming 21, no. 3 (September 1990): 256–61. http://dx.doi.org/10.1177/1046878190213004.
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Zhao, L., T. J. Montville, and D. W. Schaffner. "Computer Simulation of Clostridium botulinum Strain 56A Behavior at Low Spore Concentrations." Applied and Environmental Microbiology 69, no. 2 (February 2003): 845–51. http://dx.doi.org/10.1128/aem.69.2.845-851.2003.
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ABSTRACT It is generally assumed that spore behavior is independent of spore concentration, but recently published mathematical models indicate that this is not the case. A Monte Carlo simulation was employed in this study to further examine the independence assumption by evaluating the inherent variance in spore germination data. All simulations were carried out with @Risk software. A total of 500 to 4,000 iterations were needed for each simulation to reach convergence. Lag time and doubling time from a higher inoculum concentration were used to simulate the time to detection (TTD) at a lower inoculum concentration under otherwise identical environmental conditions. The point summaries of the simulated and observed TTDs were recorded for the 26 simulations, with kinetic data at the target inoculum concentration. The ratios of the median (Rm = medianobs/mediansim) and 90% range (Rr = 90% rangeobs/90% rangesim) were calculated. Most Rm and Rr values were greater than one, indicating that the simulated TTDs were smaller and more homogeneous than the observed ones. Rr values departed farther from one than Rm values. Ratios obtained when simulating 1 spore with 10,000 spores deviated the farthest from one. Neither ratio was significantly different from the other when simulating 1 spore with 100 spores or simulating 100 spores with 10,000 spores. When kinetic data were not available, the percent positive observed at the 95th percentile of the simulated TTDs was obtained. These simulation results confirmed that the assumption of independence between spores is not valid.
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Pan, Yongjie, Xia Li, Danyun Wang, Suosuo Li, and Lijuan Wen. "Impacts of Land Use/Land Cover Distributions on Permafrost Simulations on Tibetan Plateau." Remote Sensing 15, no. 23 (November 30, 2023): 5586. http://dx.doi.org/10.3390/rs15235586.
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The Tibetan Plateau (TP) is distributed with large areas of permafrost, which have received increasing attention as the climate warms. Accurately modeling the extent of permafrost and permafrost changes is now an important challenge for climate change research and climate modeling in this region. Uncertainty in land use and land cover (LULC), which is important information characterizing surface conditions, directly affects the accuracy of the simulation of permafrost changes in land surface models. In order to investigate the effect of LULC uncertainty on permafrost simulation, we conducted simulation experiments on the TP using the Community Land Model, version 5 (CLM5) with five high-resolution LULC products in this study. Firstly, we evaluated the simulation results using shallow soil temperature data and deep borehole data at several sites. The results show that the model performs well in simulating shallow soil temperatures and deep soil temperature profiles. The effect of different land use products on the shallow soil temperature and deep soil temperature contours is not obvious due to the small differences in land use products at these sites. Although there is little difference in the simulating results of different land use products when compared to the permafrost distribution map, the differences are noticeable for the simulation of the active layer. Land cover had a greater impact on soil temperature simulations in regions with greater land use inconsistency, such as at the junction of bare soil and grassland in the northwestern part of the TP, as well as in the southeast region with complex topography. The main way in which this effect occurs is that land cover affects the net surface radiation, which in turn causes differences in soil temperature simulations. In addition, we discuss other factors affecting permafrost simulation results and point out that increasing the model plant function types as well as carefully selecting LULC products is one of the most important ways to improve the simulation performance of land-surface models in permafrost regions.
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McMillian, Dave, Dave Johnson, and Gareth Walter. "Simulation: flight simulation." Manufacturing Engineer 70, no. 7 (1991): 32. http://dx.doi.org/10.1049/me:19910158.
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Lindák, Stanislav, Radoslav Majdan, Ivan Janoško, Miroslav Pap, and Mário Szabó. "Hydraulic Device for Simulation of Pressure Shocks." Acta Technologica Agriculturae 17, no. 2 (August 15, 2014): 44–48. http://dx.doi.org/10.2478/ata-2014-0010.
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Abstract This work is focused on the design of a hydraulic device on which simulations of pressure shocks can be performed. The hydraulic device was constructed to allow simulations of pressure shocks transferred directly in operating conditions because simulation programs for hydraulic accumulators have only theoretical values while simulation on the designed hydraulic device enables obtaining specific readings directly in operating conditions that can be set. At the first control measurement on the hydraulic device, there occurred pressure shocks generated by the hydraulic device itself, these pressure shocks being undesirable in hydraulic circuits. In order to eliminate pressure shocks in the circuit, a diaphragm accumulator was added to the hydraulic device and was used to verify the function of simulating pressure shocks and eliminating undesirable pressure shocks. During the second control measurement on the hydraulic device, a reduction of unwanted pressure shocks was shown with the help of added diaphragm accumulator, thus the function of the hydraulic device to simulate pressure shocks was confirmed, which may also refect practical application in hydraulic circuits of mobile machines.
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Szántó, András, and Sándor Hajdu. "Vehicle Modelling and Simulation in Simulink." International Journal of Engineering and Management Sciences 4, no. 1 (March 3, 2019): 260–65. http://dx.doi.org/10.21791/ijems.2019.1.33.
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In this paper a vehicle dynamics model is presented, which is an example that contains all the necessary aspects of making a decent vehicle model. Several examples show the use of such a model: basic vehicle dynamics phenomena can be recognized with the simulation of a detailed vehicle model. We are dealing with the connection between downforce and under/oversteer in this paper. In addition, the use of numerical simulations in the field of control systems is pointed out by an example of simulating an ABS control for the vehicle.
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Kirner, Raoul, Wilfried Noell, Toralf Scharf, and Reinhard Voelkel. "Coherent Ray Tracing Simulation Of Non-Imaging Laser Beam Shaping With Multi-Aperture Elements." EPJ Web of Conferences 215 (2019): 01001. http://dx.doi.org/10.1051/epjconf/201921501001.
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The application of laser light sources for illumination tasks like in mask aligner lithography relies on non-imaging optical systems with multi-aperture elements for beam shaping. When simulating such systems, the traditional approach is to separate the beam-shaping part (incoherent simulation) from dealing with coherence properties of the illuminating laser light source (diffraction theory with statistical treatment). We present an approach using Gaussian beam decomposition to include coherence simulation into ray tracing, combining these two parts, to get a complete picture in one simulation. We discuss source definition for such simulations, and verify our assumptions on a well-known system. We then apply our approach to an imaging beam shaping setup with microoptical multi-aperture elements. We compare the simulation to measurements of a similar beam-shaping setup with a 193 nm continuous-wave laser in a mask-aligner configuration.