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Full-Text Articles in Physical Sciences and Mathematics

Modeling And Verification Of Scene Of C3+Ato System Based On Timed Automata, Zhenhai Zhang, Yao Jie Apr 2021

Modeling And Verification Of Scene Of C3+Ato System Based On Timed Automata, Zhenhai Zhang, Yao Jie

Journal of System Simulation

Abstract: The C3+ATO system is in the experimental stage in our country and has the characteristics of high automation degree and high safety requirement at present. In order to confirm whether the specific function of the high-speed railway C3+ATO system meets the corresponding technical specification under the specific scene, a formal modeling and verification method based on the timed automata is proposed. The station automatic departure scene is selected as the modeling object. The functional requirements of C3+ATO system specification are extracted and the timed automata model of the scene is established. The message sequence chart of the corresponding process …


Operation Resilience Optimization Of Power System Considering Generalized Energy Storage, Weiqing Sun, Zhang Jie, Ye Lei, Han Dong Apr 2021

Operation Resilience Optimization Of Power System Considering Generalized Energy Storage, Weiqing Sun, Zhang Jie, Ye Lei, Han Dong

Journal of System Simulation

Abstract: Based on the definition and principle of power system resilience, combining the traditional energy storage equipment with the demand response, an optimization method of power system operation resilience considering generalized energy storage is proposed. Five attack schemes based on topology are evaluated according to four indexes, and the most disadvantageous attack strategy is selected to simulate the damage of power system. Taking the minimum operating cost of the system as the objective, a combined scheduling model involving wind power station and energy storage unit is carried out. A generalized energy storage scheduling method is proposed to improve the …


Study On Virtual And Real Entity Configuration Of Army Units Lvc Tactical Training, Gao Ang, Zhiming Dong, Qisheng Guo, Guohui Zhang Apr 2021

Study On Virtual And Real Entity Configuration Of Army Units Lvc Tactical Training, Gao Ang, Zhiming Dong, Qisheng Guo, Guohui Zhang

Journal of System Simulation

Abstract: Aiming at the problem that “real soldiers” in the LVC system cannot observe “virtual soldiers” and cannot completely meet the army's tactical training needs, the research on the configuration under the condition of limited interaction between virtual and real entities is carried out. Taking equipment is as the node, taking the interaction between the equipment that conforms to the objective facts of combat as the edge. An undirected graph description example of a virtual-real node interaction is build. All the complete subgraphs in the undirected graph are all the configuration modes of virtual and real entities, under which any …


Mesoscopic Traffic Simulation Model And Calibration Considering Stretching-Segment Design, Zhaocheng He, Xuanhua Lin, Peilin Nie, Ronghui Zhang Apr 2021

Mesoscopic Traffic Simulation Model And Calibration Considering Stretching-Segment Design, Zhaocheng He, Xuanhua Lin, Peilin Nie, Ronghui Zhang

Journal of System Simulation

Abstract: In order to make the simulation model fit the characteristics of urban traffic, both high accuracy and high performance, a lightweight mesoscopic traffic simulation system and the process of calibration are established. The speed-density model and vertical queue model are equivalent to the vehicle movement processes, the simulation accuracy and calibration efficiency are improved by the stretching-segment design at urban intersections of vertical queuing model, and the real individual vehicle information is used as the calibration data source. The application of the model in Xuancheng urban road network shows that, compared with the vertical queuing model, it can …


Load System Modeling Of Ultra-Supercritical Coal-Fired Power Unit Based On Improved Particle Swarm Optimization, Yuzhen Sun, Yiwei Tang, Li Shuai Apr 2021

Load System Modeling Of Ultra-Supercritical Coal-Fired Power Unit Based On Improved Particle Swarm Optimization, Yuzhen Sun, Yiwei Tang, Li Shuai

Journal of System Simulation

Abstract: Aiming at the difficulties in modeling due to variables coupling of ultra-supercritical coal-fired power unit and defects in basic particle swarm optimization, an improved particle swarm optimization algorithm for modeling of load system is proposed. The algorithm introduces the idea of adaptive, Cauchy mutation and gradient guidance crossover, which improves the problems of particle swarm optimization algorithm being prone to premature convergence and has the poor local searching ability. By collecting the actual operation data of the power plant, using the adaptive Cauchy mutation and gradient guidance cross particle swarm optimization (GMGPSO) algorithm, the model established and validated …


Personalized Game Recommendation Method Based On Implicit Feedback, Sha Jing, Gongli Zeng, Yang Yang, Wei Yao Apr 2021

Personalized Game Recommendation Method Based On Implicit Feedback, Sha Jing, Gongli Zeng, Yang Yang, Wei Yao

Journal of System Simulation

Abstract: Traditional recommendation systems often use explicit feedback for personalized recommendations. But the explicit feedback data is not easy to obtain, and the quality is poor, and the recommendation results unable to meet the requitrment of the user. Implicit feedback data is easier to obtain and can provide users with the better content. A personalized game recommendation method based on implicit feedback data is proposed. The method builds an implicit feedback recommendation model for game user data based on implicit feedback data such as the game duration and game numbers. A personalized recommendation of the game is implemented through an …


Simulation And Optimization Of Support Resource Allocation For Multi-Aircraft Large Fleet Re Dispatch, Xu Gang, Zhang Lei, Yonggang Yun, Du Li Apr 2021

Simulation And Optimization Of Support Resource Allocation For Multi-Aircraft Large Fleet Re Dispatch, Xu Gang, Zhang Lei, Yonggang Yun, Du Li

Journal of System Simulation

Abstract: In view of the complex combination of support resources of multi-aircraft large fleet re dispatch, based on the new complex factors of different models, different support expectation time and different main resource types, the simulation model of multi-aircraft support process based on queuing network is established and a simulation algorithm for the optimal allocation of support resources is proposed. The algorithm takes the total time of fleet support, the average time of aircraft support, the average intensity of fleet support, the cost of resources, the balance of free and busy support, the balance of resource supply and demand as …


Subway System Resilience Evaluation In Based On Anp-Extension Cloud Model, Qingjun Guo, Qianwen Hao, Yijie Wang, Wang Jing Apr 2021

Subway System Resilience Evaluation In Based On Anp-Extension Cloud Model, Qingjun Guo, Qianwen Hao, Yijie Wang, Wang Jing

Journal of System Simulation

Abstract: In order to improve the safety defense ability and risk resistance level of the subway construction site, it is necessary to improve the risk resistance and accident recovery ability of the safety system. The resilience theory is applied in the safety management of subway construction engineering by defining whether the resilience connotation is applicable to the safety system. According to the bibliometric method and Delphi method, the resilience evaluation index is selected and the system resilience is evaluated by constructing comprehensive evaluation model of ANP-extension cloud. The Xi'an 14th Metro Line is taken as an applilation example. The evaluation …


Modeling And Simulation Of Electric Vehicle Industry Development Based On System Dynamics, Yueqiang Fu, Tiantian Xia Apr 2021

Modeling And Simulation Of Electric Vehicle Industry Development Based On System Dynamics, Yueqiang Fu, Tiantian Xia

Journal of System Simulation

Abstract: New energy electric vehicle are the main trend of automobile industry upgrading. It plays an important role in ensuring the energy security and improving the ecological environment. It is of theoretical and practical significance to carry out research on the development of new energy electric vehicles. The affecting factors are systematically analyzed, the causal relationship model and stock flow model are established, and the dynamic equation of the model are determined and the parameter assignments are made. The model is verified and the system simulation and analysis are performed. The development trend and main influencing factors of …


Technology Evolution Network Model And Simulation Based On Patent Citation Network, You Ge, Guo Hao, Liu Xiang Mar 2021

Technology Evolution Network Model And Simulation Based On Patent Citation Network, You Ge, Guo Hao, Liu Xiang

Journal of System Simulation

Abstract: On the basis of on the patent citation network and complex networks, a technology evolution network model is constrcucted, which revealed the topology structure, evolution rules and dynamics of the technology evolution network. By introducing time and fitness preferential attachments mechanism, the effect of time factor and selection law of “survival of the fittest” on evolution of network structure during the technology evolution is studied. The results showed that the technology evolution network had the characteristic of scale-free, which is the result of global selection of “survival of the fittest” in the process of technology accumulation; The effect of …


Research On The Method Of Operational Concept Description Based On Sysml, Siming Peng, Xiao Gang, Qingzhang Yu, Zeming Li Mar 2021

Research On The Method Of Operational Concept Description Based On Sysml, Siming Peng, Xiao Gang, Qingzhang Yu, Zeming Li

Journal of System Simulation

Abstract: For the convenience of understanding and communication between researchers among different domains, the standardized method for operational concept description is preferred. Hence, based on the principles of systems architecture, the System Model Language (SysML) is proposed for the visualized and standardized description of operational concept. The form of combination for Department of Defense Architecture Framework (DoDAF) and SysML during the description of operational concept is analyzed, and the multi-view point products are used to descript the operational background, capability requirement and systems architecture as well as the operational activity of operational concept. The "Distributed Lethality" is utilized as an …


Comparative Study Of Energy Management Strategy Based On Value Loss Of Tram Hybrid Power System, Guo Ai, Chen Chao, Junjie Shi, Zhengjie Liu, Weirong Chen, Jiayi Liang, Liu Nan Mar 2021

Comparative Study Of Energy Management Strategy Based On Value Loss Of Tram Hybrid Power System, Guo Ai, Chen Chao, Junjie Shi, Zhengjie Liu, Weirong Chen, Jiayi Liang, Liu Nan

Journal of System Simulation

Abstract: In order to comprehensively evaluate the economy of fuel cell hybrid power system for tram and improve its durability, a value loss function based on the life of fuel cell and lithium battery in hybrid system is proposed. The demanded power in actual conditions is adopted and the value loss function is used to analyze the three energy policies including the state machine, power following, and minimum equivalent hydrogen consumption. The simulation results show that the value loss of state machine strategy is the smallest, and compared with power following and equivalent hydrogen consumption minimization strategies, this method …


A Survey Of Edge Computing Resource Allocation And Task Scheduling Optimization, Wang Ling, Chuge Wu, Wenhui Fan Mar 2021

A Survey Of Edge Computing Resource Allocation And Task Scheduling Optimization, Wang Ling, Chuge Wu, Wenhui Fan

Journal of System Simulation

Abstract: With the rapid development of Internet of Things (IoT) and mobile terminals, the concept of edge computing arises. By moving the computation and storage capacity to the edge of network, edge computing is able to deal with a large amount of data produced by IoT devices and the responsive request from IoT application. To improve the utility of edge resource, the quality of service and quality of user experience, resource allocation and task scheduling optimization problems under edge computing attract wide attention. It becomes more difficult due to the geographic separated and heterogeneous features of edge computing resource as …


An Improved Social Force Model For Crowd Simulation, Changhua Li, Yang Jing, Zhijie Li Mar 2021

An Improved Social Force Model For Crowd Simulation, Changhua Li, Yang Jing, Zhijie Li

Journal of System Simulation

Abstract: In view of the traditional social force model, it is difficult to deal with the problems of single pedestrian trajectory and loose crowd in the process of crowd evacuation, and an improved social force model is proposed. Based on the original social force model, the movement trajectory of the person is changed by considering the choice of the movement direction The intensity of panic and attraction in the process of pedestrian evacuation is considered to reproduce the self-organizing behavior in the process of pedestrian evacuation, and the simulations are performed in individual and group mode. The authenticity of the …


Regional Integrated Energy System Model Based On Seasonal Load Difference, Songzhi Zhang Mar 2021

Regional Integrated Energy System Model Based On Seasonal Load Difference, Songzhi Zhang

Journal of System Simulation

Abstract: In order to study the coupling of electricity, heat and natural gas in the integrated regional comprehensive energy system, proposes a general energy hub model considering the load difference between winter and summer is proposed. The establishes the coupling matrix under the model is established, combined with, and combines the steady-state calculation method of natural gas network and distribution network, and develops different operation modes are developed to restrain the fluctuation of distribution network voltage and natural gas network pressure. The simulation is carried out on MATLAB/Simulink platform. The results show that the proposed model and calculation …


Study On Navigation Simulation Method Of Crude Oil Fleet In Bridge Area, Chunhui Zhou, Hongxun Huang, Wanxia Yi, Lijia Chen, Yuanqiao Wen, Linxu Tan Mar 2021

Study On Navigation Simulation Method Of Crude Oil Fleet In Bridge Area, Chunhui Zhou, Hongxun Huang, Wanxia Yi, Lijia Chen, Yuanqiao Wen, Linxu Tan

Journal of System Simulation

Abstract: In view of the safety of over-scale fleet sailing through bridge, the water area of Wuhan Yangtze River Bridge is taken as the research area. Numerical simulation of flow field is conducted based on MIKE software to analyze the changes of water flow in different water periods and their effects on ship navigation. On this basis, according to the simulation results of the flow field, several test conditions are set up by using the Large Ship Maneuvering Simulator to carry out the simulation test of over-scale fleet sailing through the bridge. The results show that under the preset wind …


Research On Indoor Emergency Evacuation Simulation Of Multi-Exit Based On Social Force Model, Haixiang Guo, Zeng Yang, Weiming Chen Mar 2021

Research On Indoor Emergency Evacuation Simulation Of Multi-Exit Based On Social Force Model, Haixiang Guo, Zeng Yang, Weiming Chen

Journal of System Simulation

Abstract: With the frequent occurrence of emergencies, how to evacuate dense pedestrians safely from indoor space with limited export is the key and difficult point of emergency evacuation research. Taking a university auditorium as an example to simulate through Anylogic, and the degree of consciousness is introduced to comprehensively reflect the safety education, safety training and familiarity of pedestrians and the expected speed of pedestrians in the primary social force model is improved. To solve the problem of uneven utilization of exports in multi-exit indoor, optimization plans including partition guidance and change the structure of exports are proposed. Simulation results …


Intelligent Genetic Algorithm For Workforce Scheduling Considering Service Level In It Maintenance Service, Ruiying Chen, Chengtao Wang, Zhenyuan Liu Mar 2021

Intelligent Genetic Algorithm For Workforce Scheduling Considering Service Level In It Maintenance Service, Ruiying Chen, Chengtao Wang, Zhenyuan Liu

Journal of System Simulation

Abstract: Aiming at resolving the faults quickly and effectively with limited human resource,an IT maintenance service model with the consideration of service level is proposed, A knowledge model is proposed,a variety of mutation operators and crossover operators are designed. and the improved genetic algorithm (IGA), the intelligent genetic algorithm based on knowledge model (KIGA) and the adaptive intelligent genetic algorithm based on knowledge model (KAIGA) are formed. The results show that the adaptive mutation and crossover probability can accelerate the convergence speed of the solution, and the knowledge model can also improve the optimization effect of the solution


Guaranteed Cost Preview And Repetitive Control For Uncertain Linear Discrete Time-Delay Systems, Yonghong Lan, Jinlin He Mar 2021

Guaranteed Cost Preview And Repetitive Control For Uncertain Linear Discrete Time-Delay Systems, Yonghong Lan, Jinlin He

Journal of System Simulation

Abstract: For a class of uncertain linear discrete time-delay systems, a design method for guaranteed cost preview and repetitive controller is proposed . By introducing a repetitive controller in the forward channel to improve the tracking accuracy of the system, L-order difference operators are used to construct an augmented error system that contains preview information but does not include time delay, and the design problem of guaranteed cost preview and repetitive controller is converted into an output feedback adjustment problem. Using the Lyapunov stability theory and the linear matrix inequality method, the sufficient conditions for guaranteeing the asymptotic stability of …


Sar Image Target Recognition Based On Across Convolution Network Feature Fusion, Xinyang Feng, Shao Chao Mar 2021

Sar Image Target Recognition Based On Across Convolution Network Feature Fusion, Xinyang Feng, Shao Chao

Journal of System Simulation

Abstract: Convolutional neural networks have been widely used in the field of synthetic aperture radar image target recognition. Based on the LeNet-5 neural network model, a SAR image target recognition method are initialized across convolution network feature fusion is proposed. The LeNet-5 network parameters on the basis of MNIST handwritten data. The deep and shallow features of the SAR image are extracted, and the principal component analysis on the shallow features is performed to obtain key category information. Deep features and shallow features are fused and are classified and recognised by sent to collaborative representation. Experimental results show that …


Neural Network Optimized Sensorless Permanent Magnet Synchronous Motor Control System, Lixin Ma, Yongjie Zhu, Leyan Ji Mar 2021

Neural Network Optimized Sensorless Permanent Magnet Synchronous Motor Control System, Lixin Ma, Yongjie Zhu, Leyan Ji

Journal of System Simulation

Abstract: In order to solve the poor accuracy of the speed and rotor position of permanent magnet synchronous motor caused by sensor, a sensorless control system is proposed to calculate the speed and rotor position of PMSM with extended Kalman filtering algorithm. BP neural network algorithm is used to optimize the covariance matrix Q and R of EKF, which improves the accurate calculation values of rotational speed and rotor position. At the same time, the speed sliding mode controller combined with the current feed-forward decoupling unit are used to improve the stability of the whole control system. The simulation results …


Simulation Of Benefit Distribution In Platform Delivery Mode, Zheng Wen, Chenxi Dou, Zhe Zhang Mar 2021

Simulation Of Benefit Distribution In Platform Delivery Mode, Zheng Wen, Chenxi Dou, Zhe Zhang

Journal of System Simulation

Abstract: Aiming at the benefit distribution relationship of platform delivery mode(PDM), the multi-agents-based model is applied to construct the benefit distribution of PDM. The Swarm simulation platform is used to explore the trading status changes of the participants under different scales; Considering the cost-profit condition, the sense of relative deprivation is introduced as the index to express the individual perception in exploring the emergency of the co-effective relationship of the individual perception and the benefit distribution in systematic and emergence points. The model and its results can reveal the benefit distribution states of the existing PDM structure and the collective …


Network Traffic Anomaly Detection Method For Imbalanced Data, Shuqin Dong, Bin Zhang Mar 2021

Network Traffic Anomaly Detection Method For Imbalanced Data, Shuqin Dong, Bin Zhang

Journal of System Simulation

Abstract: Aiming at the poor detection performances caused by the low feature extraction accuracy of rare traffic attacks from scarce samples, a network traffic anomaly detection method for imbalanced data is proposed. A traffic anomaly detection model is designed, in which the traffic features in different feature spaces are learned by alternating activation functions, architectures, corrupted rates and dropout rates of stacked denoising autoencoder (SDA), and the low accuracy in extracting features of rare traffic attacks in a single space is solved. A batch normalization algorithm is designed, and the Adam algorithm is adopted to train parameters of …


Performance Evaluation Method For Load Control System Considering “Two Detailed Rules”, Yinsong Wang, Wang Kai Mar 2021

Performance Evaluation Method For Load Control System Considering “Two Detailed Rules”, Yinsong Wang, Wang Kai

Journal of System Simulation

Abstract: With the promulgation of the "two detailed rules" of regional power grid,the requirements by power system thermal power units are more and more strict, and has greatly affected their economic development. In order to combine the performance evaluation theory of multivariable control system with the engineering practice, the covariance index of multivariable control system is improved, and the assessment method of AGC (Automatic Generation Control) is analyzed and summarized. The improved covariance index of load Control system and the economic index based on the "two detailed rules" are proposed, and the comprehensive evaluation of load Control system is made …


Research On Generation Technology Of Computer Generated Force In Lvc Training System, Gao Ang, Zhiming Dong, Guohui Zhang, Liang Tao, Qisheng Guo Mar 2021

Research On Generation Technology Of Computer Generated Force In Lvc Training System, Gao Ang, Zhiming Dong, Guohui Zhang, Liang Tao, Qisheng Guo

Journal of System Simulation

Abstract: LVC training system of the combat equipment under the condition of confrontation is an effective means of training, aiming at the problem that in LVC training system, computer generated forces are difficult to meet the demand of training problems. The concept of LVC training and LVC training system is clarified, according to the relationship between model and system structure, the corresponding modeling technology requirements of three different hierarchical models, namely logical range entity configuration, command entity and combat entity, are expounded. According to the specific requirements, four computer-generated force generation methods are proposed, namely, logical target range virtual and …


Simulation Platform For Source-Load Control Of Active Power Based On Modular Architecture, Hu Yang, Wenying Liu, Liping Zhu, Li Xiao, Weizhou Wang Mar 2021

Simulation Platform For Source-Load Control Of Active Power Based On Modular Architecture, Hu Yang, Wenying Liu, Liping Zhu, Li Xiao, Weizhou Wang

Journal of System Simulation

Abstract: The integrated proportion of wind power is increasing year by year, and the source-load coordinated control of active power can effectively improve the level of wind power consumption. In order to ensure the effective application of the strategy, a simulation platform based on modular architecture is developed for source-load control of active power, including SQL Server database, timing control module of data interaction, calculation module of source-load control strategy, and output display module. The simulation platform solves the automatic control of data interaction timing in the process of source-load control, and visualizes the effect of the source-load control, so …


Path Designing Of Multi-Omnidirectional Wheel Collaborative Sorting Platform, Li Qi, Wang Wei Mar 2021

Path Designing Of Multi-Omnidirectional Wheel Collaborative Sorting Platform, Li Qi, Wang Wei

Journal of System Simulation

Abstract: Aiming at the problems of low efficiency, high labor cost and low flexibility of traditional logistics sorting system, an automatic logistics sorting system is designed. The improved A* algorithm and the artificial potential field method are used to realize the automatic path planning of the system by taking the transportation path as the research object. The A* algorithm is improved by adjusting the weights of actual cost and estimated cost, and the artificial potential field method is improved by adding virtual sub-target points and adjusting adaptive parameters, so as to complete the function of path planning of goods. Simulation …


Simulation Analysis Of Impact Of Complex Network On Herd Effect, Li Feng, Wei Ying Mar 2021

Simulation Analysis Of Impact Of Complex Network On Herd Effect, Li Feng, Wei Ying

Journal of System Simulation

Abstract: Herd behavior is valuable but complicated. The impact of different type complex network on herd effect is analyzed by multi-agent modeling and simulation. In the model, herd behavior of decision-maker is modeled based on the advanced evidences from empirical study. Through simulation, not only the conclusions drawn from traditional mathematical modeling are verified, but also the whole evolving process of herd effect is inspected and the evolving speed related features can be used to evaluate performances of herd effect. More important, simulation results show the network structure of different type complex networks is one of the key factors …


Frequency Coordinated Control Strategy Of Microgrid Based On Fuzzy Prediction, Kunping Zhang, Hao Lin Mar 2021

Frequency Coordinated Control Strategy Of Microgrid Based On Fuzzy Prediction, Kunping Zhang, Hao Lin

Journal of System Simulation

Abstract: Aiming at the problem of frequency fluctuation of wind power generation connected to microgrid, a frequency coordinated control strategy based on model predictive control (MPC) is proposed. In this strategy, the wind turbine and plug-in hybrid electric vehicle (PHEV) are included in the frequency control system. The pitch angle of the fan and the charge and discharge of PHEV are controlled to adjust the grid frequency and supplement the frequency modulation resources of microgrid. WTG pitch angle control system and PHEV power control system are modeled, and their control principles are described. In order to prevent excessive use of …


Modeling And Simulation Technology Of Flight Maneuver For Large Scale Battlefield, Chu Yang, Liu Zhi, Lintao Dou Mar 2021

Modeling And Simulation Technology Of Flight Maneuver For Large Scale Battlefield, Chu Yang, Liu Zhi, Lintao Dou

Journal of System Simulation

Abstract: In order to meet the requirements of the system simulation acceleration ability of the intelligent countermeasure game system, analyzes the large-scale battlefield space large-scale air force simulation modeling method is analyzed. Combined with the requirements of the system countermeasure for the fidelity, real-time and accuracy of the air vehicle modeling, based on the original air vehicle motion model, by reducing variables, simplifying parameters, equivalent calculation and other methods, a fast flight maneuver simulation modeling method is derived, which can realize the correct modeling of the trajectory and attitude of the aircraft, conform to the general flight physical laws, meet …