Articoli di riviste: "SimulationX"

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Zhao, Si Jun, Jia Yua Shan e Lu Yan Bi. "6-Axis Serial Robot Simulation Based on SimulationX". Applied Mechanics and Materials 152-154 (gennaio 2012): 1010–17. http://dx.doi.org/10.4028/www.scientific.net/amm.152-154.1010.

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This paper presents research and simulation analysis on kinematics and dynamics problem based on the 6-axis serial robot. By means of Denavit-Hartenberg method, the robot kinematics model is established as well as and the derivation process of kinematic and inverse kinematic resolution is described in detail. Furthermore, in software simulationX, robot system model including mechanical sub-system and control sub-system are founded. Additionally, through simulation, different performances of robot are illustrated based on different trajectory planning and control. In this way a theoretical reference is provided for the further study on trajectory planning and controls of 6-axis serial robot.

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Vulić, Nenad, Karlo Bratić, Branko Lalić e Ladislav Stazić. "Implementing Simulationx in the Modelling of Marine Shafting Steady State Torsional Vibrations". Polish Maritime Research 28, n. 2 (1 giugno 2021): 63–71. http://dx.doi.org/10.2478/pomr-2021-0022.

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Abstract Marine propulsion shafting systems are exposed to torsional vibrations originating from excitations in their prime movers and propellers. It is essential to analyse their steady state response in the earliest stage of ship design. The paper describes the implementation of SimulationX software based upon simulation modelling for these calculations. This software can be used either by the design office of the shipyard or by the classification society for verification within the plan approval phase. Some specifics of the input data preparation are briefly discussed. In addition, the simulation results depend on the modelling approach chosen. For these reasons, the real two-stroke Diesel engine ship propulsion system was chosen and several different models were implemented for system modelling. SimulationX calculation results are compared with those of two well-known and field-proven programs that use an analytical approach. Finally, the results are compared with the measurements performed on the actual newly built ship. Discussion reviews the selected SimulationX model, and its verification and validation in the case of engine cylinders with normal ignition.

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Jomartov, Assylbek. "Model of Two-Link Planar Robot on SimulationX". Advanced Materials Research 1025-1026 (settembre 2014): 897–901. http://dx.doi.org/10.4028/www.scientific.net/amr.1025-1026.897.

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The paper shows a simulation of the motion of simple planar robot, consisting of two links and kinematic drives on SimulationX. Model of robot takes into account the characteristics of the servomotors. The simulation results of robot motion can be obtained in a convenient graphical form for subsequent analysis. The model can be used in laboratory work by students in the universities of Kazakhstan.

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Cao, Yong Xin, Yan Fang Liu, Xiang Yang Xu e Yang Yang. "Simulation for Handing and Stability of Vehicle Based on SimulationX". Advanced Materials Research 291-294 (luglio 2011): 537–41. http://dx.doi.org/10.4028/www.scientific.net/amr.291-294.537.

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To build a dynamic vehicle model is the most important work in the field of digital virtual prototyping technology for studying on its handing and stability. A 54 degrees of freedom multi-body vehicle model with tire, suspension and steering was established in SimulationX software. Time domain response under steering wheel step input and frequency response under steering wheel sinusoidal input were obtained, the changing trend of indicators with different speeds was presented, the handing and stability of vehicle model was evaluated, also the impact of caster angle and kingpin inclination to handing and stability was analyzed. The simulation results were consistent with theoretical analysis and actual situation.

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Liu, Ping, e Bin Cheng Li. "Vibration Analysis and Simulation of the Marine Diesel Generating Sets Gear System". Advanced Materials Research 804 (settembre 2013): 337–42. http://dx.doi.org/10.4028/www.scientific.net/amr.804.337.

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This paper analyzes the dynamical theory of the marine diesel generating sets gear system and establishes the 3D model. Base on the software ITI SimulationX, it establishes simulation model system and analyses the vibration which considers both internal and external parametric excitations.

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Jiang, En Qiao, Shu Han Wang, Jing Ke Du, Xiang Yang Xu e Wen Yong Li. "Simulation of the Nozzle Electro-Hydraulic Servo Valve with ITI-SimulationX". Advanced Materials Research 690-693 (maggio 2013): 2912–17. http://dx.doi.org/10.4028/www.scientific.net/amr.690-693.2912.

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The structure and principle of the nozzle electro-hydraulic servo valve was introduced, and the complicated characteristics of mechanical, electrical, hydraulic, and magnetic are studied in this paper. The model of the nozzle electro-hydraulic servo valve was built based on the ITI-SimulationX software platform. The static and dynamic simulation processes were presented and analyzed regarding the nozzle electro-hydraulic servo valve. The nozzle electro-hydraulic servo valve has some advantages of rapid time respond, high stability and reliability. This paper shows the special capabilities of SimlationX to develop such a multi-domain model.

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Zhang, Hong Chen, Feng Li Li e Li Qing Zhang. "Small Refrigerator Simulation and Experimental Study". Applied Mechanics and Materials 477-478 (dicembre 2013): 392–95. http://dx.doi.org/10.4028/www.scientific.net/amm.477-478.392.

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Through the study of the actual single-stage vapor compression refrigeration system of each components, to build the mathematical model of each components, through the study of the nature of the refrigerant R22 , to build the thermodynamic properties and transport properties of mathematical model, the use of modelica language in ITI SimulationX 2.0 software platform , and the simulation results and actual operation are compared.

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Kuhn, Christian, Thomas Risch e Markus Golder. "Simulation of the Conveying Speed on Vibration Conveyors Using 1D-Mechanical Modules in SimulationX". innoTRAC Journal 1 (4 dicembre 2020): 107–14. http://dx.doi.org/10.14464/innotrac.v1i0.470.

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Vibration conveyors are technical systems which generate a stream of materials on basis of vibrations. The vibrations lead to continuous change between acceleration forces and friction. In the practical operation high conveying speeds shall be accomplished with a defined use of the driving force. In this article a simulation model in the software SimulationX is introduced which utilities basic mechanical correlations to calculate the conveying speed. With the help of the presented model influences of vibration movement curve on the conveying speed can be portrayed and analyzed.

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Cao, Feng Ping, Li Fa Zhou e Yong Di Wang. "Study on Optimization Matching Algorithm for Automotive Powertrain". Applied Mechanics and Materials 635-637 (settembre 2014): 1890–94. http://dx.doi.org/10.4028/www.scientific.net/amm.635-637.1890.

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In order to reduce fuel consumption and ensure dynamic performance of the car, an automotive powertrain optimization algorithm was presented in the paper. Firstly, the evaluation index of automobile dynamic performance and fuel economy were introduced. Then, the objective function was built, and the transmission and main reducer transmission ratios were designed as variables, and parameters of the vehicle transmission system were optimized by using the genetic algorithm. Finally, a vehicle simulation model by SimulationX software was established, and the power and economy performance before and after optimization were compared and analyzed.

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Yue, Hui Jun, Yan Fang Liu, Gang Shi e Xiang Yang Xu. "Free Vibration Model and Characteristics of Planetary Gear Sets". Advanced Materials Research 694-697 (maggio 2013): 383–88. http://dx.doi.org/10.4028/www.scientific.net/amr.694-697.383.

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Planetary gear sets have advantages of little noise, high transmission ratio, compact arrangement, so it has been widely applied in automobile and aerospace applications over the years. Using Lagrange equation, a free vibration theoretical model of a single planetary gear set was built, which was solved with modal superposition method. Combined with theoretical results, two types of modeling methods of planetary gear structures with the simulation platform SimulationX were studied. The simulation model suitable for analyzing vibration characteristic of planetary gear sets and inherent vibration characteristic in different situation were studied with the optimal modeling method. Important influencing factors of planetary gear sets vibration characteristic were studied and reference for dynamic best designing planetary gear transmission sets were provided.

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Qiu, Xu Yun, Liang Xiu Zhang, Hui Jun Wang e Yong Hui Liu. "Research on Power Matching of Automatic Variable Transmission". Applied Mechanics and Materials 427-429 (settembre 2013): 1246–49. http://dx.doi.org/10.4028/www.scientific.net/amm.427-429.1246.

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Automatic Variable Transmission (AVT) is composed of a metal belt CVT unit and a step speed changing transmission component. According to the needs of automotive conditions, AVT can realize continuously variable transmission and gear transmission, which not only play the advantage of gear transmission efficiency, but also overcome the deficiency of CVT when it is in high-speed. In the paper, the transmission matching rule is introduced, and engine model is established using engine test data. Based on SimulationX software, a vehicle that equips AVT is used for modeling and simulation. Finally the power matching is researched.

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Bao, Mingxi, Xiangdong Ni e Shiwei Kang. "Efficiency Analysis of Pump-controlled Motor System of Hydraulic Machinery Continuously Variable Transmission for Agricultural Machinery". MATEC Web of Conferences 319 (2020): 03002. http://dx.doi.org/10.1051/matecconf/202031903002.

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In order to improve the efficiency of Hydraulic Machinery Continuously Variable Transmission (HMCVT), studying the efficiency of its pump-controlled motor system is of great significance to promote the practical application of HMCVT in agricultural machinery. By analyzing the HMCVT transmission principle and the driving parameters of medium and large vehicles, determine the HMCVT transmission scheme that meets the actual requirements. The simulation model of the whole HMCVT system was established by SimulationX software, and the relationship curves between different engine speeds and HMCVT output speeds were given. And determine the effect of the pump-controlled motor system on the response parameters of HMCVT under different volumetric efficiency.

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Kim, Dong Myoung, Jung Min Lee, Won Jee Jung e Joo Sup Jang. "A Study on the Efficiency of a Load Sensing Main Control Valve Using SimulationX". Transactions of the Korean Society of Mechanical Engineers A 40, n. 1 (1 gennaio 2016): 87–95. http://dx.doi.org/10.3795/ksme-a.2016.40.1.087.

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Yoon, Y. H., e J. S. Jang. "SimulationX, Multi-domain Simulation and Modeling tool for the Design, Analysis, and Optimization of Complex systems". Journal of The Korean Society for Fluid Power & Construction Equipments 9, n. 1 (1 marzo 2012): 56–69. http://dx.doi.org/10.7839/ksfc.2012.9.1.056.

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Shen, Xiao Xia, Jun Zhou, Jian Xin Deng e Hong Kui Tan. "Research on Cushion of Boom Cylinder in Hydraulic Excavator". Advanced Materials Research 354-355 (ottobre 2011): 679–83. http://dx.doi.org/10.4028/www.scientific.net/amr.354-355.679.

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In some circumstances, huge mass, if not cushioned, may pull the piston to a halt at rod side or head side at ease with a tremendous velocity causing huge impact. As a result of this issue, the boom cylinder of hydraulic excavator provides cushioning apparatus at the rod side stroke end. This paper discusses and analyses the cushioning apparatus structure of boom cylinder, and then proposes a numerical simulation model with SimulationX. It is known to us that many dynamic parameters of boom cylinder vary as mechanical structure or motion of excavator attachment changes. Thus in order to study the relationship between kinetic parameters and cushioning capability of boom cylinder, an excavator attachment model is built next. The last part of this paper is devoted to the obtained simulation results.

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Zhang, Xiao Gang, e Long Quan. "The Performance Analysis and Experimental Research of Multiple Oil Ports Axial Piston Pump which Able to Control the Movement of Differential Cylinder Directly in the Closed Circuit". Advanced Materials Research 308-310 (agosto 2011): 388–400. http://dx.doi.org/10.4028/www.scientific.net/amr.308-310.388.

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In order to realize that an asymmetric flow piston pump can control an asymmetric differential cylinder, a proposal about the application of an asymmetric flow-distributing axial piston pump is put forward. The new type of piston pump can output the flows with two different values to control the movement of the differential cylinder directly in the closed circuit and realize much ideal result of the control of the differential cylinder by a single pump. Also a simulation model of the hydraulic pump is established under the circumstance of SimulationX software, considering the characteristics of the movement of an individual piston, the oil compressibility, and the flow distribution area changed with the rotation angle. The key data of the pump is defined by means of digital simulation. In particular, an analysis is made on the dimension of the unloading groove of the port plate and the characteristics of the flow pulse of the pump. Furthermore, an experimental model pump is manufactured, the basic performances of the pump is tested on the experimental platform at various rotatory speeds such as pressure, flow and noise, in the end the accuracy of the principle is verified.

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Xu, Teng, Qin-Xiang Xia, Jinchuan Long e Xiaobin Long. "A study on multi-domain modeling and simulation of precision high-speed servo numerical control punching press". Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 232, n. 7 (2 aprile 2018): 830–44. http://dx.doi.org/10.1177/0959651818762945.

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The multi-domain modeling and simulation of the precision high-speed punching press was carried out using the software SimulationX in this article. The key technical problems of the multi-domain modeling, such as the establishment of the sub-systems of mechanics with accurate structures and dimensions, improvement of modeling accuracy and simulation efficiency by dividing and dealing with components in group and import of the displacement-depended stamping forces on the stamping dies, have been resolved to establish the integral multi-domain model, which contains sub-systems of mechanics, hydraulic and servo driven of the complete punching press. Vibration quantity of the punching press was predicted through simulation, and validity of the multi-domain model was confirmed by experimental measurement. The vibration reduction in the punching press based on the topology optimization of the slider and design of rotational speed variation curve of the servo motor were investigated. The results show that through topology optimization, the mass of the slider could be decreased under the premise of guaranteeing the structural strength, by which the vibration quantity of the punching press can be decreased; rotational speed of the servo motor could be decreased during the stamping period by designing the rotational speed variation curve, which leads to a decrease in acceleration and vibration of the slider during that period, with which the forming precision can be guaranteed.

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Li, Bin Cheng, e Bing Han. "Simulation of the Application of Pneumatic Propulsion Method in Tourist Submarine". Applied Mechanics and Materials 43 (dicembre 2010): 603–9. http://dx.doi.org/10.4028/www.scientific.net/amm.43.603.

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In order to realize propulsion system and oxygen system of tourist submarines be secure, eco-friendly, efficient, reliable, economical, a combination of ordinary air motor and ACM high-pressure air bottle is adopted for providing propulsion and oxygen. The calculation and selection of the appropriate air motor and high-pressure bottle are based on the propulsive requirement of a tourist submarine. A model consists of high-pressure bottle, air motor, propeller and the resistance of the tourist submarine is established in SimulationX. The underwater speed and it’s duration are obtained through calculation as the rev, thrust force, torque of the propeller, etc. The possibility of application of pneumatic propulsion method in tourist submarine is analysed. Results illustrate that: on the premise of lightened quality of the propulsion system, pneumatic propulsion method fulfills the required underwater speed and it’s duration.

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WANG, Hongjun. "Application of SimulationX and Hardware-in-the-loop in Design and Research of Servo Precision Press". Journal of Mechanical Engineering 48, n. 06 (2012): 51. http://dx.doi.org/10.3901/jme.2012.06.051.

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Huang, Jiahai, Hu Zhao, Long Quan e Xiaogang Zhang. "Development of an asymmetric axial piston pump for displacement-controlled system". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 228, n. 8 (24 ottobre 2013): 1418–30. http://dx.doi.org/10.1177/0954406213508385.

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Pump-controlled systems can eliminate throttling losses and improve the work efficiency of mobile hydraulic system. But one difficult problem for that is the differential volumetric flow through a single rod cylinder which is widely used in mobile hydraulic system. Several solutions have been presented to deal with it so far, but there still has not been a cost-effective solution to it. In recent years, an asymmetric pump-controlled asymmetric cylinder strategy has been presented to deal with this problem. In order to achieve this goal, an asymmetric axial piston pump with three ports was developed in this research. The flow rate ratio of the three ports of asymmetric axial piston pump was designed as 1: γ:(1 − γ), in which γ was the area ratio of a single rod cylinder. An important task in the development of asymmetric axial piston pump was the design of the valve plate. There were three intake/discharge slots (slots A, B, and T) in the valve plate. The pumping dynamics of a fixed displacement asymmetric axial piston pump were investigated using software package ITI-SimulationX® and the performances of its prototype were tested. Simulation and experimental results show that with careful design, a V-shaped cross-section groove at the leading side of slot T can effectively improve the performance of asymmetric axial piston pump, and delivery pressure performance of port B is better than that of port T. Therefore, port T should be linked with low-pressure sources such as accumulator, and port B can be connected to high pressure sources. This work lays a theoretical foundation for a new exploration to pump-controlled system.

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Lee, San Seong, Won Jee Chung, Dong Jae Lim, Tae Hyung Cha, Soo Tae Kim, Jeong Sil Lee e Kyung Shin Choi. "SimulationX<sup>Ⓡ</sup> –based Modeling for Valve-Plate Notch Design of Variable Swash-Plate Axial Piston Pump". Korean Society of Manufacturing Process Engineers 17, n. 4 (30 agosto 2018): 104–12. http://dx.doi.org/10.14775/ksmpe.2018.17.4.104.

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MAHAJAN, DHIRAJ K., e SUMIT BASU. "ON THE SIMULATION OF UNIAXIAL, COMPRESSIVE BEHAVIOR OF AMORPHOUS, GLASSY POLYMERS WITH MOLECULAR DYNAMICS". International Journal of Applied Mechanics 02, n. 03 (settembre 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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Greif, Hajo. "Exploring Minds: Modes of Modeling and Simulation in Artificial Intelligence". Perspectives on Science 29, n. 4 (luglio 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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Li, Yongxing, Hongfei Jia, Ya-Nan Zhou e Lili Yang. "Simulation research on pedestrian counter flow subconscious behavior". International Journal of Modern Physics C 28, n. 02 (febbraio 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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Janíček, František, Martin Mucha, Karol Česnek e Jozef Kováčik. "Controlled Switching of the T402 Transformer in the Križovany 400kV Substation". Journal of Electrical Engineering 61, n. 1 (1 gennaio 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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Herrington, Alaina, e Joseph Tacy. "Crossing the Power Line: Using Virtual Simulation to Prepare the First Responders of Utility Linemen". Informatics 7, n. 3 (29 luglio 2020): 26. http://dx.doi.org/10.3390/informatics7030026.

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Virtual reality (VR) healthcare simulation has helped learners develop skills that are transferable to real-word conditions. Innovative strategies are needed to train workers to improve community safety. The purpose of this pilot project was to evaluate the use of a VR simulation applying the International Nursing Association for Clinical Simulation and Learning (INACSL) Standards of Best Practice: SimulationSM Simulation Design with eight power line workers. Six power industry supervisors and educators assisted in facilitating three VR simulations with eight linemen participants. Kotter’s eight steps to leading change and the INACSL Standards of Best Practice: SimulationSM Simulation Design were utilized in working with energy leaders and VR developers to carry out this pilot project. Pre- and post-implementation surveys demonstrated a 28% improvement in participants’ learning outcomes. All three learning objectives were met. This project demonstrated the successful application of a translational framework and the INACSL Standards of Best Practice: SimulationSM in a VR context in the power industry. This process may be helpful to guide or inspire further adoption of VR in unconventional settings.

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YI, H. H., L. J. FAN e Y. Y. CHEN. "LATTICE BOLTZMANN SIMULATION OF THE MOTION OF SPHERICAL PARTICLES IN STEADY POISEUILLE FLOW". International Journal of Modern Physics C 20, n. 06 (giugno 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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Vasileva, Svetlana, e Aleksandar Milev. "Simulation Studies of Distributed Two-phase Locking in Distributed Database Management Systems". Information Technologies and Control 13, n. 1-2 (1 giugno 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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Wu, Qing, Maksym Spiryagin, Ingemar Persson, Chris Bosomworth e Colin Cole. "Parallel computing of wheel-rail contact". Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit 234, n. 10 (8 ottobre 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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Pias, Claus. "On the Epistemology of Computer Simulation". ZMK Zeitschrift für Medien- und Kulturforschung 2/1/2011: Offene Objekte 2, n. 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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Wu, Yongxing, Fei Peng, Yang Peng, Xiaoyang Kong, Heming Liang e 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, n. 11 (18 novembre 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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Słodkowski, Marcin, Patryk Gawryszewski, Patryk Marcinkowski, Dominik Setniewski e Joanna Porter-Sobieraj. "Simulations of Energy Losses in the Bulk Nuclear Medium Using Hydrodynamics on the Graphics Cards (GPU)". Proceedings 10, n. 1 (15 aprile 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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Yana, Janchai, Piyarat Nimmanpipug e Vannajan Sanghiran Lee. "J-9 DRY AND WET MOLECULAR DYNAMICS SIMULATIONS OF NAFION(R) POLYMER ELECTROLYTE FUEL CELL MEMBRANE(Session: Simulation)". Proceedings of the Asian Symposium on Materials and Processing 2006 (2006): 165. http://dx.doi.org/10.1299/jsmeasmp.2006.165.

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Matzner, Nils, e Robert Herrenbrück. "Simulating a Climate Engineering Crisis". Simulation & Gaming 48, n. 2 (30 novembre 2016): 268–90. http://dx.doi.org/10.1177/1046878116680513.

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Background. At the 2015 Paris Agreement to limit global warming to a maximum of 2 degrees, climate activists and researchers began to look for alternative measures. Climate engineering (CE) - the deliberate manipulation of the planetary environment to decelerate climate change - emerges as a possibly effective, albeit risky and conflictual, option. Aim. This article aims both at simulating a plausible international scenario of negotiation over solar climate engineering deployment, and at utilizing the rules of Model United Nations (MUN) for collaborative learning in a university class. Furthermore, the article intends to provide a framework for simulations about CE that could easily be reproduced. Method. MUN is an established and well-tested foundation for a simulation with students, including preparation leading up to the simulation and feedback rounds afterwards. We repeated the simulation three times, recorded the sessions as well as the debriefings, and gathered interesting insight by comparing the results. Result. For our CE simulations, we discovered: 1. Divergent interests (e.g. global north vs global south). 2. Power struggle (e.g. role of the veto powers). 3. Scientific and political ignorance (e.g. decision-making under uncertainty). 4. Risk politics (e.g. trade-offs between climate change risks vs. CE risks). Conclusion. MUN qualifies well for simulating a CE crisis. However, known lacks in MUN settings (like underrepresentation of non-state actors) must be discussed during the debriefing. These simulations illustrate possible future conflicts over CE without being prescriptive in any way.

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Dolag, K., S. Borgani, S. Schindler, A. Diaferio e A. M. Bykov. "Simulation Techniques for Cosmological Simulations". Space Science Reviews 134, n. 1-4 (febbraio 2008): 229–68. http://dx.doi.org/10.1007/s11214-008-9316-5.

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Erwina, Novry, Didit Adytia, Sri Redjeki Pudjaprasetya e Toni Nuryaman. "Staggered Conservative Scheme for 2-Dimensional Shallow Water Flows". Fluids 5, n. 3 (31 agosto 2020): 149. http://dx.doi.org/10.3390/fluids5030149.

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Simulating discontinuous phenomena such as shock waves and wave breaking during wave propagation and run-up has been a challenging task for wave modeller. This requires a robust, accurate, and efficient numerical implementation. In this paper, we propose a two-dimensional numerical model for simulating wave propagation and run-up in shallow areas. We implemented numerically the 2-dimensional Shallow Water Equations (SWE) on a staggered grid by applying the momentum conserving approximation in the advection terms. The numerical model is named MCS-2d. For simulations of wet–dry phenomena and wave run-up, a method called thin layer is used, which is essentially a calculation of the momentum deactivated in dry areas, i.e., locations where the water thickness is less than the specified threshold value. Efficiency and robustness of the scheme are demonstrated by simulations of various benchmark shallow flow tests, including those with complex bathymetry and wave run-up. The accuracy of the scheme in the calculation of the moving shoreline was validated using the analytical solutions of Thacker 1981, N-wave by Carrier et al., 2003, and solitary wave in a sloping bay by Zelt 1986. Laboratory benchmarking was performed by simulation of a solitary wave run-up on a conical island, as well as a simulation of the Monai Valley case. Here, the embedded-influxing method is used to generate an appropriate wave influx for these simulations. Simulation results were compared favorably to the analytical and experimental data. Good agreement was reached with regard to wave signals and the calculation of moving shoreline. These observations suggest that the MCS method is appropriate for simulations of varying shallow water flow.

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González-Rouco, J. F., H. Beltrami, E. Zorita e M. B. Stevens. "Borehole climatology: a discussion based on contributions from climate modeling". Climate of the Past Discussions 4, n. 1 (21 gennaio 2008): 1–80. http://dx.doi.org/10.5194/cpd-4-1-2008.

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Abstract. Progress in understanding climate variability through the last millennium leans on simulation and reconstruction efforts. Exercises blending both approaches present a great potential for answering questions relevant both for the simulation and reconstruction of past climate, and depend on the specific peculiarities of proxies and methods involved in climate reconstructions, as well as on the realism and limitations of model simulations. This paper explores research specifically related to paleoclimate modeling and borehole climatology as a branch of climate reconstruction that has contributed significantly to our knowledge of the low frequency climate evolution during the last five centuries. The text flows around three main issues that group most of the interaction between model and geothermal efforts: the use of models as a validation tool for borehole climate reconstructions; comparison of geothermal information and model simulations as a means of either model validation or inference about past climate; and implications of the degree of realism on simulating subsurface climate on estimations of future climate change. The use of multi-centennial simulations as a surrogate reality for past climate suggests that within the simplified reality of climate models, methods and assumptions in borehole reconstructions deliver a consistent picture of past climate evolution at long time scales. Comparison of model simulations and borehole profiles indicate that borehole temperatures are responding to past external forcing and that more realism in the development of the soil model components in climate models is desirable. Such an improved degree of realism is important for the simulation of subsurface climate and air-ground interaction; results indicate it could also be crucial for simulating the adequate energy balance within climate change scenario experiments.

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González-Rouco, J. F., H. Beltrami, E. Zorita e M. B. Stevens. "Borehole climatology: a discussion based on contributions from climate modeling". Climate of the Past 5, n. 1 (19 marzo 2009): 97–127. http://dx.doi.org/10.5194/cp-5-97-2009.

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Abstract (sommario):

Abstract. Progress in understanding climate variability through the last millennium leans on simulation and reconstruction efforts. Exercises blending both approaches present a great potential for answering questions relevant both for the simulation and reconstruction of past climate, and depend on the specific peculiarities of proxies and methods involved in climate reconstructions, as well as on the realism and limitations of model simulations. This paper explores research specifically related to paleoclimate modeling and borehole climatology as a branch of climate reconstruction that has contributed significantly to our knowledge of the low frequency climate evolution during the last five centuries. The text flows around three main issues that group most of the interaction between model and geothermal efforts: the use of models as a validation tool for borehole climate reconstructions; comparison of geothermal information and model simulations as a means of either model validation or inference about past climate; and implications of the degree of realism on simulating subsurface climate on estimations of future climate change. The use of multi-centennial simulations as a surrogate reality for past climate suggests that within the simplified reality of climate models, methods and assumptions in borehole reconstructions deliver a consistent picture of past climate evolution at long time scales. Comparison of model simulations and borehole profiles indicate that borehole temperatures are responding to past external forcing and that more realism in the development of the soil model components in climate models is desirable. Such an improved degree of realism is important for the simulation of subsurface climate and air-ground interaction; results indicate it could also be crucial for simulating the adequate energy balance within climate change scenario experiments.

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Zhao, L., T. J. Montville e D. W. Schaffner. "Computer Simulation of Clostridium botulinum Strain 56A Behavior at Low Spore Concentrations". Applied and Environmental Microbiology 69, n. 2 (febbraio 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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Gerritsma, Marte K., Tarek A. AlSkaif, Henk A. Fidder e Wilfried G. J. H. M. van Sark. "Flexibility of Electric Vehicle Demand: Analysis of Measured Charging Data and Simulation for the Future". World Electric Vehicle Journal 10, n. 1 (19 marzo 2019): 14. http://dx.doi.org/10.3390/wevj10010014.

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This paper proposes a method for analyzing and simulating the time-dependent flexibility of electric vehicle (EV) demand. This flexibility is influenced by charging power, which depends on the charging stations, the EV characteristics, and several environmental factors. Detailed charging station data from a Dutch case study have been analysed and used as input for a simulation. In the simulation, the interdependencies between plug-in time, connection duration, and required energy are respected. The data analysis of measured data reveals that 59% of the aggregated EV demand can be delayed for more than 8 h, and 16% for even more than 24 h. The evening peak shows high flexibility, confirming the feasibility of congestion management using smart charging within flexibility constraints. The results from the simulation show that the average daily EV demand increases by a factor 21 between the ‘Present-day’ and the ‘High’ scenario, while the maximum EV demand peak increases only by a factor 6, as a result of the limited simultaneity of the transactions. Further, simulations using the average charging power of individual measured transactions yield more accurate results than simulations using a fixed value for charging power. The proposed method for simulating future EV flexibility provides a basis for testing different smart charging algorithms.

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McClintock, Edwin, e Zhonghong Jiang. "Technology Tips: Spreadsheets: Powerful Tools for Probability Simulations". Mathematics Teacher 90, n. 7 (ottobre 1997): 572–79. http://dx.doi.org/10.5951/mt.90.7.0572.

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The Curriculum and Evaluation Standards for School Mathematics (NCTM 1989) recommends that high school students extend their K-8 experiences with simulations and experimental probability to continue to improve their intuition and build more formal concepts of theoretical probability based on these experiences. In keeping with this idea, we use spreadsheets frequently in studying and investigating probabilistic situations with both high school students and preservice mathematics teachers. Our approach includes simulations but goes beyond the simulation process as a way of learning important concepts and principles of probability. We have found that spreadsheets are a very powerful tool for simulating probabilistic situations, not only for simple problems, such as simulating coin Ripping and die tossing, but also for rather complex problem situations. In this article, we illustrate the use of spreadsheets as a simulation tool for solving a collection of probability problems. The spreadsheet program we use is Microsoft Excel (1995), but other spreadsheet programs, such as Quattro Pro (Borland 1994), can be used with the same degree of effectiveness.

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Rauter, Matthias, e Anselm Köhler. "Constraints on Entrainment and Deposition Models in Avalanche Simulations from High-Resolution Radar Data". Geosciences 10, n. 1 (25 dicembre 2019): 9. http://dx.doi.org/10.3390/geosciences10010009.

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Depth-integrated simulations of snow avalanches have become a central part of risk analysis and mitigation. However, the common practice of applying different model parameters to mimic different avalanches is unsatisfying. In here, we analyse this issue in terms of two differently sized avalanches from the full-scale avalanche test-site Vallée de la Sionne, Switzerland. We perform depth-integrated simulations with the toolkit OpenFOAM, simulating both events with the same set of model parameters. Simulation results are validated with high-resolution position data from the GEODAR radar. Rather than conducting extensive post-processing to match radar data to the output of the simulations, we generate synthetic flow signatures inside the flow model. The synthetic radar data can be directly compared with the GEODAR measurements. The comparison reveals weaknesses of the model, generally at the tail and specifically by overestimating the runout of the smaller event. Both issues are addressed by explicitly considering deposition processes in the depth-integrated model. The new deposition model significantly improves the simulation of the small avalanche, making it starve in the steep middle part of the slope. Furthermore, the deposition model enables more accurate simulations of deposition patterns and volumes and the simulation of avalanche series that are influenced by previous deposits.

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Chen, Liang, e Richard F. Serfozo. "Performance limitations of parallel simulations". Journal of Applied Mathematics and Stochastic Analysis 11, n. 3 (1 gennaio 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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Celik, Nurcin, Esfandyar Mazhari, John Canby, Omid Kazemi, Parag Sarfare, Majed S. Al-Otaibi e 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, n. 2 (aprile 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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Botsis, T., R. Ball e J. Scott. "Simulating adverse event spontaneous reporting systems as preferential attachment networks". Applied Clinical Informatics 05, n. 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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EL AJALTOUNI, ELIE, MING ZHANG, AZZEDINE BOUKERCHE e ROBSON EDUARDO DE GRANDE. "AN ADAPTIVE DYNAMIC LOAD BALANCING TECHNIQUE FOR GRID-BASED LARGE SCALE DISTRIBUTED SIMULATIONS". Journal of Interconnection Networks 10, n. 04 (dicembre 2009): 391–419. http://dx.doi.org/10.1142/s0219265909002637.

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Dynamic load balancing is a key factor in achieving high performance for large scale distributed simulations on grid infrastructures. In a grid environment, the available resources and the simulation's computation and communication behavior may experience critical run-time imbalances. Consequently, an initial static partitioning should be combined with a dynamic load balancing scheme to ensure the high performance of the distributed simulation. In this paper, we propose a dynamic load balancing scheme for distributed simulations on a grid infrastructure. Our scheme is composed of an online network analyzing service coupled with monitoring agents and a run-time model repartitioning service. We present a hierarchical scalable adaptive JXTA service based scheme and use simulation experiments to demonstrate that our proposed scheme exhibits better performance in terms of simulation execution time. Furthermore, we extend our algorithm from a local intra-cluster algorithm to a global inter-cluster algorithm and we consider the proposed global design through a formalized Discrete Event System Specification (DEVS) model system

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Steinmetz, Janina, Brittany M. Tausen e Jane L. Risen. "Mental Simulation of Visceral States Affects Preferences and Behavior". Personality and Social Psychology Bulletin 44, n. 3 (21 novembre 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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Eckels, Mary, Terry Zeilinger, Henry C. Lee, Janine Bergin, Louis P. Halamek, Nicole Yamada, Janene Fuerch, Ritu Chitkara e Jenny Quinn. "A Neonatal Intensive Care Unit’s Experience with Implementing an In-Situ Simulation and Debriefing Patient Safety Program in the Setting of a Quality Improvement Collaborative". Children 7, n. 11 (29 ottobre 2020): 202. http://dx.doi.org/10.3390/children7110202.

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Extensive neonatal resuscitation is a high acuity, low-frequency event accounting for approximately 1% of births. Neonatal resuscitation requires an interprofessional healthcare team to communicate and carry out tasks efficiently and effectively in a high adrenaline state. Implementing a neonatal patient safety simulation and debriefing program can help teams improve the behavioral, cognitive, and technical skills necessary to reduce morbidity and mortality. In Simulating Success, a 15-month quality improvement (QI) project, the Center for Advanced Pediatric and Perinatal Education (CAPE) and California Perinatal Quality Care Collaborative (CPQCC) provided outreach and training on neonatal simulation and debriefing fundamentals to individual teams, including community hospital settings, and assisted in implementing a sustainable program at each site. The primary Aim was to conduct two simulations a month, with a goal of 80% neonatal intensive care unit (NICU) staff participation in two simulations during the implementation phase. While the primary Aim was not achieved, in-situ simulations led to the identification of latent safety threats and improvement in system processes. This paper describes one unit’s QI collaborative experience implementing an in-situ neonatal simulation and debriefing program.

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Mo, Wen Hui. "Monte Carlo Simulation of Reliability for Gear". Advanced Materials Research 268-270 (luglio 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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Ji, Qiuyan, Feilong Han, Wei Qian, Qing Guo e Shulin Wan. "A machine learning-driven stochastic simulation of underground sulfide distribution with multiple constraints". Open Geosciences 13, n. 1 (1 gennaio 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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