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Full-Text Articles in Physical Sciences and Mathematics

Optizimation Of Vaccination Supply Chain Based On Scg In Nanshan District, Zhenning Dong, Shunzhou Huang, Jiajun Chen, Huiqiong Zheng Nov 2021

Optizimation Of Vaccination Supply Chain Based On Scg In Nanshan District, Zhenning Dong, Shunzhou Huang, Jiajun Chen, Huiqiong Zheng

Journal of System Simulation

Abstract: To optimize the vaccination network, inventory strategy and human resource allocation in Nanshan District, Supply Chain Guru's (SCG) network optimization method is used to select 50 alternative stations to decrease the fixed operating cost. SCG's inventory optimization method is used to set inventory strategy for each station, and simulation method is designed to compare total cost of all schemes. To optimize the opening days of vaccination stations, an medical personnel allocation rule is designed, which reduces some stations' opening days to 2 or 3 days and increases some stations' medical personnel. An simulation method is designed to compare the …


Simulation Of Civil Aircraft Takeoff Scenario Based On Mbse, Liangyu Zhao, Junjie Ye, He Qi, Guo Wei, Zhao Yong Oct 2021

Simulation Of Civil Aircraft Takeoff Scenario Based On Mbse, Liangyu Zhao, Junjie Ye, He Qi, Guo Wei, Zhao Yong

Journal of System Simulation

Abstract: Aiming at the interactions and flaws of design being difficult to be fully discovered, the requirements being hard to be traced, the early verification of system design being difficult to be realized and so on, a Model-Based System Engineering (MBSE) method is adopted to realize the simulation of civil aircraft take-off scenario. Based on the analysis of civil aircraft takeoff scenario requirements, the civil aircraft takeoff scenario simulation architecture, take-off scenario discrete logic model, and continuous physical simulation model are established. The method of fusing the SysML model and Simulink model and the 3D visualization of simulation data …


Simulation Analysis Of Assessment Method For Missile Accuracy, Shuqing Li, Zhili Zhang, Yumiao Wei, Haitao Wang Aug 2021

Simulation Analysis Of Assessment Method For Missile Accuracy, Shuqing Li, Zhili Zhang, Yumiao Wei, Haitao Wang

Journal of System Simulation

Abstract: The missile accuracy of the falling points is one of the important performance indexes of missile systems, so the assessment method is very important. An improved algorithm for missile accuracy assessment is proposed. Accuracy assessment problem is simplified as a hypothesis check for probability circle, and the accuracy difference coefficients are defined to describe the accuracy difference between the real falling points and the expected situation. Based on the probability circle method, an improved risk assessment method is put forward to balance and minimize producer's risk and consumer's risk. According to sequential check method, this risk assessment …


Hybrid System Simulation Method Based On Quantized State, Zhihua Li, Jiang De, Hanwu Shen, Zhihua Fan Aug 2021

Hybrid System Simulation Method Based On Quantized State, Zhihua Li, Jiang De, Hanwu Shen, Zhihua Fan

Journal of System Simulation

Abstract: Hybrid system simulation and discontinuity processing have always been the difficulties of the time-discretized integration methods, while Quantized State System (QSS) is a new numerical integration method based on state variable discretization. Aiming at the hybrid systems simulation, a method of QSS+DEVS is proposed. The discrete part of hybrid system is represented as DEVS model, and the continuous part of hybrid system is discretized by QSS, which can also be represented as DEVS model. The simulation model of the whole hybrid system is obtained by coupling the two DEVS models. The accuracy, efficiency and simplicity of the QSS+DEVS method …


Power-Over-Tether Unmanned Aerial System Leveraged For Trajectory Influenced Atmospheric Sensing, Daniel Rico Aug 2021

Power-Over-Tether Unmanned Aerial System Leveraged For Trajectory Influenced Atmospheric Sensing, Daniel Rico

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

The use of unmanned aerial systems (UASs) in agriculture has risen in the past decade and is helping to modernize agriculture. UASs collect and elucidate data previously difficult to obtain and are used to help increase agricultural efficiency and production. Typical commercial off-the-shelf (COTS) UASs are limited by small payloads and short flight times. Such limits inhibit their ability to provide abundant data at multiple spatiotemporal scales. In this thesis, we describe the design and construction of the tethered aircraft unmanned system (TAUS), which is a novel power-over-tether UAS configured for long-term, high throughput atmospheric monitoring with an array of …


Creating Synthetic Satellite Cloud Data Based On Gan Method, Wencong Cheng, Xiaokang Shi, Zhigang Wang Jun 2021

Creating Synthetic Satellite Cloud Data Based On Gan Method, Wencong Cheng, Xiaokang Shi, Zhigang Wang

Journal of System Simulation

Abstract: To create the synthetic satellite cloud data in the domain of Meteorology, a method based on Generative Adversarial Networks (GAN) is proposed. Depending on ability of the nonlinear mapping and the information extraction of raster data with the deep learning network, a deep generative adversarial network model is proposed to extract the corresponding information between the numerical weather prediction(NWP) products and the satellite cloud data, and then the appropriate elements of the NWP product are chosen as the input to synthesize the corresponding satellite cloud data. The experiments are conducted on the re-analysis products of the European Centre …


Development And Prospect Of Simulation Research In China, Xiaogang Qiu, Duan Hong, Xie Xu, Mengna Zhu Jun 2021

Development And Prospect Of Simulation Research In China, Xiaogang Qiu, Duan Hong, Xie Xu, Mengna Zhu

Journal of System Simulation

Abstract: It is important to treat modeling and simulation (M&S) as a discipline to advance its development. In China, M&S has been researched and applied over 40 years, and is gradually becoming an independent discipline. Modeling and simulating the complex systems are the challenge, however, this also brings grand opportunity for M&S to widen and improve itself. Since 1980s, the M&S community in China has realized the broad applications of M&S, comprehended M&S from multiple perspectives, conducted extensive research on basic questions, and discussed the composition of the basic simulation theory. By summarizing these achievements, the future works that have …


Physically Based Rendering Techniques To Visualize Thin-Film Smoothed Particle Hydrodynamics Fluid Simulations, Aditya H. Prasad Jun 2021

Physically Based Rendering Techniques To Visualize Thin-Film Smoothed Particle Hydrodynamics Fluid Simulations, Aditya H. Prasad

Dartmouth College Undergraduate Theses

This thesis introduces a methodology and workflow I developed to visualize smoothed hydrodynamic particle based simulations for the research paper ’Thin-Film Smoothed Particle Hydrodynamics Fluid’ (2021), that I co-authored. I introduce a physically based rendering model which allows point cloud simulation data representing thin film fluids and bubbles to be rendered in a photorealistic manner. This includes simulating the optic phenomenon of thin-film interference and rendering the resulting iridescent patterns. The key to the model lies in the implementation of a physically based surface shader that accounts for the interference of infinitely many internally reflected rays in its bidirectional surface …


Ar-Based Simulation Interaction And Human Factor Assessment For Human Robot Cooperation Assembly Planning, Wang Qiang, Xiumin Fan, Qichang He, Wenmin Zhu Feb 2021

Ar-Based Simulation Interaction And Human Factor Assessment For Human Robot Cooperation Assembly Planning, Wang Qiang, Xiumin Fan, Qichang He, Wenmin Zhu

Journal of System Simulation

Abstract: To improve assembly efficiency, it has become a trend for traditional manual assembly workstations to be carried out human-robot collaboration transformation. To realize the safe and fast evaluation of the improvement scheme, a general human-robot collaboration simulation method and human factor evaluation method based on Augmented Reality are proposed. Four levels of human-robot collaboration assembly simulation are established. An interactive scheme between real human and virtual robot for visual detection, perception and feedback is established. A fuzzy comprehensive evaluation model of human physiological and psychological indicators for workstation design is constructed. The prototype system is developed. Taking the assembly …


A Quantized State System Method With Adaptive Quantum, Zhihua Li, Dongjin Fu, Li Guang, Zhihua Fan Feb 2021

A Quantized State System Method With Adaptive Quantum, Zhihua Li, Dongjin Fu, Li Guang, Zhihua Fan

Journal of System Simulation

Abstract: Quantized state system (QSS) is a new numerical integration method. It has advantages over the traditional time-discrete integration methods in solving general ordinary differential equation (ODE) systems. But it is hard to choose an appropriate quantum for the QSS method. In order to improve the accuracy and efficiency of QSS, a quantized state system method with adaptive quantum (VQSS) is proposed. Combined with the idea of step control in the variable step Runge-Kutta method, it can adaptively change the quantum in the process of computation. The feasibility of this algorithm is verified by the simulation of two examples …


Architecture Design Of An Emergency Command Simulation Exercise Platform Based On Tena, Peng Zhang, Qinfu Li Jan 2021

Architecture Design Of An Emergency Command Simulation Exercise Platform Based On Tena, Peng Zhang, Qinfu Li

Journal of System Simulation

Abstract: Based on the analysis of the current situation and development needs of the emergency command simulation exercise platform and the common characteristics of most emergency command case scenarios, an emergency command simulation exercise platform architecture based on TENA (Test and Training Enabling Architecture) is designed and put forward, which can expand various simulation models such as disaster accidents, disaster-bearing subjects, higher-lower linkage command organizations, rescue forces, natural environment, etc. in a multi-granularity and modular manner, and interface with various exercise support and analysis evaluation tools, as well as heterogeneous systems such as external three-dimensional simulation, virtual reality/augmented reality equipment …


A Quantization-Based Integration Method For Stiff Ordinary Differential Equations, Zhihua Li, Jiang De, Chenjia Wu, Zhihua Fan Jan 2021

A Quantization-Based Integration Method For Stiff Ordinary Differential Equations, Zhihua Li, Jiang De, Chenjia Wu, Zhihua Fan

Journal of System Simulation

Abstract: QSS(Quantized State System) has advantages over the traditional time-discrete integration methods in solving general ordinary differential equation (ODE) systems, but it is not suitable for solving the stiff ODE systems. To effectively solve the stiff ODE systems, a step-correction optimization algorithm based on QSS (SCOA based-on QSS) is proposed, which combines the ideas of the QSS method and the implicit trapezoidal integral method. The simulation results of three typical stiff ODE cases show that the SCOA based-on QSS algorithm has advantages over other algorithms, and the simulation accuracy can be significantly improved by appropriately reducing the quantum size.


Collision Simulation Analysis Of Sam Movable Guardrail, Hongjun Cui, Sixue Li, Minqing Zhu, Li Xia Jan 2021

Collision Simulation Analysis Of Sam Movable Guardrail, Hongjun Cui, Sixue Li, Minqing Zhu, Li Xia

Journal of System Simulation

Abstract: Aiming at the problem of low anti-collision grade of the movable guardrail at the opening of the central divding belt of the expressway, a SAm-level concrete movable guardrail and a new connecting device are proposed. Based on the finite element method, the collision model between the vehicle and the guardrail is established, and the collision process is also calculated by LS-DYNA. According to the collision results of different vehicle types, the safety performance of the guardrail is evaluated in terms of cushioning, blocking and guiding performance. The OIV value is less than 12 m/s for small vehicles' collision with …


Study On Validation Of Simulation Models Based On Weight Matrix Gray Relational Analysis, Xiaolei Ning, Yingxia Wu, Zhanqi Chen Jan 2021

Study On Validation Of Simulation Models Based On Weight Matrix Gray Relational Analysis, Xiaolei Ning, Yingxia Wu, Zhanqi Chen

Journal of System Simulation

Abstract: When used to validation of simulation models, ordinary gray relational analysis (GRA) usually stresses the similarity but ignores the nearness between the simulation test time series and flight test time series, while the nearness is part of model error. To reduce the risk in application of GRA to validation of simulation models, a new matrix gray relational analysis was proposed, which was in view of the similarity and the nearness between the simulation test time series and flight test time series, so it had a higher accuracy and reliability. The new model could solve the relational analysis problem with …


Research On Safety Protection Compositive Simulation Test Bed For Electric Secondary System, Zheniu Zhou, Angang Zheng, Heping Zou Jan 2021

Research On Safety Protection Compositive Simulation Test Bed For Electric Secondary System, Zheniu Zhou, Angang Zheng, Heping Zou

Journal of System Simulation

Abstract: Existing information and network security simulation methodologies of model construction were analyzed and compared with each other, and applicability and limitations of each of them were summarized. Then according to safety protection needs to electric secondary system, based on previous research results of security simulation aiming at individual and partial objects, a safety protection compositive simulation test bed was designed and implemented in which eight kinds of simulation technology and solutions were integrated. This test bed included four simulation layers and seventeen categories of simulation test, and achieved a large scale, distributed, linkage-type simulation for comprehensive information security. This …


Modeling And Simulation Of Traction System In Hybrid Shunting Locomotive, Kun Shen, Wang Ling, Wang Jian, Xiaoyang Yao Jan 2021

Modeling And Simulation Of Traction System In Hybrid Shunting Locomotive, Kun Shen, Wang Ling, Wang Jian, Xiaoyang Yao

Journal of System Simulation

Abstract: The structure of traction system in hybrid shunting locomotive was analyzed, and the working principles of traction system under multiform power models were introduced. Based on which, the models of traction system and power accumulators of this hybrid shunting locomotive were built by MATLAB/Simulink, then the simulation experiments on hybrid shunting locomotive with the power models of hybrid power, and pure diesel generator power or pure accumulator power were done respectively. The simulation results show that hybrid shunting locomotive can achieve reliable operation in diflFerent conditions by the designed main circuit structure, parameters and system energy management strategy.