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Three-Dimensional Cloud Simulation Of Satellite Cloud Map Based On Sph Method, Zhou Hao, Shuoben Bi, Yucheng Gong, Wang Jun, Dequan Ling 2019 School of Remote Sensing, Nanjing University of Information Science and Technology, Nanjing 210044, China;

Three-Dimensional Cloud Simulation Of Satellite Cloud Map Based On Sph Method, Zhou Hao, Shuoben Bi, Yucheng Gong, Wang Jun, Dequan Ling

Journal of System Simulation

Abstract: A fast cloud three-dimensional simulation algorithm based on smoothed particle hydrodynamics (SPH) is proposed. The two-dimensional contours of the real cloud are extracted from the satellite cloud image, and the cloud contour curves are fitted with different levels of circular clouds. The obtained circle is extended to the three-dimensional space with the center and the radius as necessary to form the spherical shape. According to the principle of SPH, a certain number of particles are generated in the generated cloud three-dimensional sphere; and the particles are given the initial properties such as color, size, speed and smooth kernel, so …


Analysis Of Initialization Variables Selection In Multi-Domain Modeling, Guangyuan Li 2019 Chongqing University of Arts and Sciences, Chongqing 402160, China;

Analysis Of Initialization Variables Selection In Multi-Domain Modeling, Guangyuan Li

Journal of System Simulation

Abstract: In multi-domain modeling, the problem of initial consistency must be settled to solve differential algebraic equations (DAEs). Structural analysis is capable of verifying the initial consistency, solving some initial values and determining the degree of freedom, but not capable of affirming the variables that need to be initialized. If improper selection is made for the initiation variables, it will become low efficient and even fail to solve and simulate the model. After analyzing the initial consistency of DAEs, a strategy based on DM decomposition is proposed for selecting the initialization variables. The method decomposes the system into two …


Temperature Field Simulation Analysis Of Common Rail Injector Based On Multi-Field Coupling, Yutao Chen, Zuoqun Wang, Zhengwei Long, Mingrui Zhang, Qingsong An, Guibing Chen 2019 1. Key Laboratory of Efficient Utilization of Low and Medium Grade Energy, Ministry of Education, Tianjin University, Tianjin 300350, China; ;

Temperature Field Simulation Analysis Of Common Rail Injector Based On Multi-Field Coupling, Yutao Chen, Zuoqun Wang, Zhengwei Long, Mingrui Zhang, Qingsong An, Guibing Chen

Journal of System Simulation

Abstract: The reliability of high pressure common rail injector depends on the calculation accuracy of its temperature changing. Due to the temperature measurement limitation and difficulty, in order to obtain more detailed temperature distribution, a coupling physical model is established in this paper based on multi-fields coupling analysis method, and a method based on the uni-directional coupling for calculating the temperature distribution of injector accurately is developed. The results show that the convective heat transfer coefficient varies with the flow state and the multi-field coupling method can correct the convective heat transfer coefficient according to the flow state automatically, which …


Face Skin Detection And Color Transferring, Fangfang Chen, Zhongping Ji 2019 Institute of Graphics and Image, Hangzhou Dianzi University, Hangzhou 310018, China;

Face Skin Detection And Color Transferring, Fangfang Chen, Zhongping Ji

Journal of System Simulation

Abstract: The reliable and accurate extraction of facial skin is a key and urgent problem for skin detection. This paper proposes a face alignment and GMM (Gaussian mixture model) to achieve face skin detection. We use the SCUT-FBP5500 face database, combined with SOM (self-organizing Maps) and K-means clustering method to cluster 9 pairs of facial features, and then use ResNet50 to predict face score. The color migration algorithm based on Lab space is used to migrate and edit the face color.The facts prove that the method has certain effect.


Chaotic Time Series Prediction Based On Gaussian Processes Mixture, Zhenjie Feng, Fan Yu 2019 1. School of Computer and Information Engineering, Anyang Normal University, Anyang 455000, China; ;

Chaotic Time Series Prediction Based On Gaussian Processes Mixture, Zhenjie Feng, Fan Yu

Journal of System Simulation

Abstract: Aiming at the problem that the existing learning algorithms of Gaussian processes mixture (GPM) model, such as Markov Chain Monte Carlo (MCMC), variation or leave one out, have high computational complexity, a hidden variables posterior hard-cut iterative training algorithm is proposed, which simplifies the training process of the model. The GPM model based on the proposed algorithm is applied to chaotic time series prediction. The effects of embedding dimension, time delay, learning sample number, and testing sample numbers on predictive ability are discussed. It is demonstrated by the experimental results that the prediction of the GPM model is more …


Single-Phase Grounding Fault Location In Wind Farm Based On Zero-Sequence Current, Yanyan Zheng, Yongli Zhu, Tongtong Liu, Shanshan Su 2019 School of Electrical and Electronic Engineering, North China Electric Power University Baoding, Baoding 071003, China;

Single-Phase Grounding Fault Location In Wind Farm Based On Zero-Sequence Current, Yanyan Zheng, Yongli Zhu, Tongtong Liu, Shanshan Su

Journal of System Simulation

Abstract: The wind power system is different from the conventional transmission system, and its collecting line contains multi sections of cable. The collecting line of wind farm adopts overhead line-power cable hybrid transmission form, and its distance is about 3~20km. Wind farm 35kV neutral point grounding method is different from the conventional distribution network, and its neutral point adopts the winding grounding transformer. In hybrid transmission lines, due to the different velocities of traveling wave in power cable and overhead line, the traditional location algorithm for uniform transmission line is not suitable. A new method of single-phase to grounding fault …


Dynamic Shadow Detection And Tracking Of Online Video From Mobile View, Youpeng Zhang, Wang Chun, Yanli Liu 2019 1. National Key Laboratory of Fundamental Science on Synthetic Vision, Sichuan University, Chengdu 610065, China; ;

Dynamic Shadow Detection And Tracking Of Online Video From Mobile View, Youpeng Zhang, Wang Chun, Yanli Liu

Journal of System Simulation

Abstract: A shadow edge detection and tracking framework based on optical flow tracking in outdoor scenes is proposed. The SVM is trained by using the edge information features extracted from the known results; the optical flow tracking is performed on the two frames before and after; and the SVM model is used to identify the points corresponding to the shadow features from the neighborhood Canny confidence edges of the unstable tracking points. A method for dynamically updating the SVM is designed for the new material problem of the scene caused by the viewpoint movement. The complexity of the shadow projection …


Research On Physical Simulation Method Of Micro-Doppler Effect Of Laser Scattering Echo, Du Jian, Zhang Xing, Hongming Zhao, Gao Yang, Cao Qiang, Xinlan Zhang 2019 1. Technology on Special System Simulation Laboratory, Beijing Simulation Center Science, Beijing 100854, China; ;2.The Institute of Technological Sciences, Wuhan University, Wuhan 430072, China; ;

Research On Physical Simulation Method Of Micro-Doppler Effect Of Laser Scattering Echo, Du Jian, Zhang Xing, Hongming Zhao, Gao Yang, Cao Qiang, Xinlan Zhang

Journal of System Simulation

Abstract: In order to realize the physical simulation of the micro-Doppler effect of laser detection echo, a mathematical model of micro-Doppler effect for single-point motion is established. Two physics simulation methods for laser scattering echo micro-Doppler effect based on controllable vibrator and acousto-optical modulator are proposed, and two experiment systems are set up. The experimental results show that the two methods can achieve the modulation of laser wave echo. The advantage of the simulation scheme based on controllable vibration is that the simulation results are closer to the actual situation, but the frequency modulation range is smaller, while the …


Research On Cost-Effectiveness Analysis And Modeling Of Equipment, Yueqiang Zhao, An Shi, Mai Qiang, Yinyin Lin 2019 1. School of Management, Harbin Institute of Technology, Harbin 150001, China; ;2. Defense Technology Academy of CASIC, Beijing 100854, China; ;

Research On Cost-Effectiveness Analysis And Modeling Of Equipment, Yueqiang Zhao, An Shi, Mai Qiang, Yinyin Lin

Journal of System Simulation

Abstract: There are many methods to study the cost effectiveness analysis of equipment. It is very important to choose the right method and method combination . On this basis of analyzing and sorting out the research status at home and abroad, the collation and comparative study of cost estimation methods and modeling methods are carried out.The methods and classifications of effectiveness evaluation and calculating and aggregating efficiency indicators are sorted out. The methods suitable for cost-effectiveness analysis and decision-making are summarized. The characteristics of these methods in the analysis of equipment system and their applicability to engineering application are pointed …


Numerical Simulation Of Spread And Infection Risk Of Respiratory Pathogens In The Aircraft Cabin, Jiaquan Lin, Fengshan Sun, Yachong Li 2019 Institute of Electronic Information and Automation, Civil Aviation University of China, Tianjin 300300, China;

Numerical Simulation Of Spread And Infection Risk Of Respiratory Pathogens In The Aircraft Cabin, Jiaquan Lin, Fengshan Sun, Yachong Li

Journal of System Simulation

Abstract: In order to study the transmission law of respiratory pathogens through the breath of the sick passengers in the aircraft cabin and reduce the risk of infection, the numerical model of respiratory pathogens spread in Boeing737 economy cabin is established. The dynamic propagation process of respiratory pathogens released by the sick passenger is simulated. The risk of infection for other passengers is obtained. Taking SEI (Susceptible Exposure Index) as an evaluation index,,the seats with the least risk of infection for other passengers are obtained based on the simulated data by changing the seats of the sick passengers. Some seats …


Study On Model And Accumulation Rule For Departure Check-In Queues, Zhiwei Xing, Junxian Jiang, Luo Xiao, Luo Qian, Yang Yang 2019 1. School of Electronic Information and Automation, Civil Aviation University Of China, Tianjin 300300, China; ;

Study On Model And Accumulation Rule For Departure Check-In Queues, Zhiwei Xing, Junxian Jiang, Luo Xiao, Luo Qian, Yang Yang

Journal of System Simulation

Abstract: The aggregation rule of departure passengers in the terminal building is studied in combination with human behavior dynamics. Based on this, the change rule of queuing length of departing passengers on non-full-open check-in island is studied. The queuing process is discretized by introducing the concept of time series, and the queue length Markov Chain is obtained in the serpentine queuing form. Then, the aggregation rate of each time series is predicted by the single-flight departure passenger aggregation model. By selecting the appropriate value of the check-in counter service rate, the check-in queuing length model of multiple adjacent flights is …


Simulation And Experiment Of Friction Modeling And Compensation Of Scara, Li Lin, Yanlong Lin, Yanbiao Zou 2019 College of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510000, China;

Simulation And Experiment Of Friction Modeling And Compensation Of Scara, Li Lin, Yanlong Lin, Yanbiao Zou

Journal of System Simulation

Abstract: Due to the friction of joints, the localization accuracy of Scara robot is deteriorated. To deal with this problem, the friction of robot joints is modeled, identified and compensated. A method of identifying the friction force of robot working in limited working space is proposed. The Lugre friction model is used to describe the joint friction of the robots. By allowing the robot to track the sinusoidal curve, the relationship between the friction torque and the joint velocity is established, and the friction parameters are identified. The adaptive control method is proposed to control the robot. The experiment and …


Multi-Objective Model Of Distribution Route Problem For Fresh Electricity Commerce Under Uncertain Demand, Zhang Qian, Xiong Ying, Mingke He, Zhang Hao 2019 1. Beijing Technology and Business University, Beijing 100048, China; ;

Multi-Objective Model Of Distribution Route Problem For Fresh Electricity Commerce Under Uncertain Demand, Zhang Qian, Xiong Ying, Mingke He, Zhang Hao

Journal of System Simulation

Abstract: Considering the distribution cost, freshness of fresh products, carbon emissions and customer demand uncertainty and other factors, a multi-objective optimization model of distribution path planning is established. Based on the robust optimization method for dealing with uncertain problems, the multi-objective model of distribution routing planning is optimized for the situation that the discrete demand belongs to the uncertainty set of ellipsoid. The model is solved by using the main target method and fruit fly algorithm. It is proved that the model and algorithm are robust and can effectively suppress the disturbance caused by the uncertainty of the demand. This …


Ads-B In Based Conflict Prediction And Conflict-Free Trajectory Planning For Multi-Aircraft, Siyuan Zhang, Xianying Li, Xiaoyun Shen 2019 Tianjin Key Lab for Advanced Signal and Image Processing, Civil Aviation University of China, Tianjin 300300, China;

Ads-B In Based Conflict Prediction And Conflict-Free Trajectory Planning For Multi-Aircraft, Siyuan Zhang, Xianying Li, Xiaoyun Shen

Journal of System Simulation

Abstract: For free flight of future, it is necessary to continuously detect conflicts and plan safe flight paths. Through in-depth analysis of detection principle of TCAS, combined with the characteristics of ADS-B data, the target within the scope of ADS-B IN surveillance is classified and given a risk factor, and the TCAS function is implemented in the ADS-B IN simulation software. For complex conflict scenarios with multi-aircraft, by meshing the conflict region and discretizing the flight procedure, the genetic algorithm is then used to calculate the optimal conflict-free trajectory based on risk factors. Two common multi-aircraft conflict scenarios are …


Joint Resource Partitioning And Offloading Analysis In Heterogeneous Ultra-Dense Networks, Zhen Yan, Jiangpan Shi, Qiaoshou Liu 2019 1. Key Laboratory of Optical Communication and Networks, Chongqing University of Posts and Telecommunications, Chongqing 400065, China; ;2. State Grid Information & Telecommunication Co. Ltd, Beijing 102200, China;;

Joint Resource Partitioning And Offloading Analysis In Heterogeneous Ultra-Dense Networks, Zhen Yan, Jiangpan Shi, Qiaoshou Liu

Journal of System Simulation

Abstract: For the problem of load balancing between macro base station and small base station in heterogeneous ultra-dense networks, a general offloading framework is proposed based on the distance between users and the nearest base station. By partitioning network spectrum resource and using stochastic geometry, the expression of coverage probability and average ergodic rate of users in the fixed region and the random region are deduced on the basis of guaranteeing the quality of service of the macro users offloaded. The simulation results show that the combination of resource partitioning and offloading effectively improves the coverage probability and average ergodic …


The Simulation Of Ac Servo Network Control System, Wang Lin, Chongquan Zhong 2019 1. Faculty of Electronic Information and Electrical Engineering, Dalian University of Technology, Dalian 116024, China; ;2. School of Electrical and Information Engineering, Dalian Jiaotong University, Dalian 116028, China;

The Simulation Of Ac Servo Network Control System, Wang Lin, Chongquan Zhong

Journal of System Simulation

Abstract: The networking trend of AC servo system is becoming more and more remarkable. The research on permanent magnet synchronous motor(PMSM) mainly focuses on the continuous improvement of control strategy. It is rarely combined with solving real network delay and packet loss problems. The vector control strategy of PMSM is studied. In view of the delay and packet loss in the network environment, the mathematical model of network control system (NCS) is derived, and a simulation model based on TrueTime and Simulink is established to simulate the delay and packet loss phenomenon in the network transmission. The results show that …


Research On Sins/Gps Integrated Navigation System Based On Grid Reference Frame For Transpolar Aircraft, Lijun Song, Zhe Li, Qiangwen Fu, He Bo 2019 1. Xi’an University of Architecture and Technology, Xi’an 710055, China;; ;

Research On Sins/Gps Integrated Navigation System Based On Grid Reference Frame For Transpolar Aircraft, Lijun Song, Zhe Li, Qiangwen Fu, He Bo

Journal of System Simulation

Abstract: The mechanics equations of grid navigation system are improved and analyzed in the paper. It is simulated that the SINS/GPS Integrated Navigation System works in the low latitude region and the polar regions. The theoretic is supported by the research of the SINS/GPS Integrated Navigation System working in the polar regions. The result of simulation shows that the performance of SINS/GPS Integrated Navigation System is improved and the shortcomings of SINS and GPS are avoided. By comparing the simulation results of the SINS/GPS Integrated Navigation System, the navigation precision is consistent when the SINS/GPS Integrated Navigation System works …


Multi-Channel Transmission Optimization Of Campus Internet Of Things Based On Pheromone Genetic Algorithm, Zhiyong Chen, Liu Hao 2019 1. Educational Technology and Information Center, Guangdong Medical University , Zhanjiang 524023, China; ;

Multi-Channel Transmission Optimization Of Campus Internet Of Things Based On Pheromone Genetic Algorithm, Zhiyong Chen, Liu Hao

Journal of System Simulation

Abstract: Aiming at the difficulty in selecting and optimizing the multi-path transmission of campus Internet of Things information, an optimization algorithm of network multi-path transmission based on intelligent optimization algorithm is proposed. Based on the standard genetic algorithm and the concept of pheromone concentration in ant colony algorithm, this algorithm improves the global optimization ability and convergence efficiency by controlling the evolution direction of individuals, and designs and constructs an evaluation index mathematical model which conforms to the characteristics of multi-channel information transmission optimization in the Internet of Things. The mathematical model of the evaluation index realizes the multi-channel comprehensive …


Research On Fast Acquisition Algorithm For High Bit Rate Spread Spectrum System, Aizhen Wang, Meisong Luan, Hu Jiao, Zhumei Tian, Guofeng Ren 2019 1. Xinzhou Teachers University, Xinzhou 034000, China; ;

Research On Fast Acquisition Algorithm For High Bit Rate Spread Spectrum System, Aizhen Wang, Meisong Luan, Hu Jiao, Zhumei Tian, Guofeng Ren

Journal of System Simulation

Abstract: In a high-bit-rate spread spectrum communication system, due to the limitation of hardware processing speed, traditional acquisition methods cannot accomplish quick capture of PN code. In order to solve this problem, parallel structure is usually used in high-bit-rate receivers. In this paper, several traditional acquisition methods are analyzed and compared, and a parallel fast acquisition algorithm based on PMF-FFT for large frequency offset is proposed. This algorithm is based on parallel matched filtering and parallel FFT, and can accomplish the capture of multiple code phases and frequency offsets simultaneously. The principle of the algorithm is deduced in …


Hpc-Based Virtual Flight Test Method For Multidisciplinary Multiphysical Field Coupling, Tie Ming, Yu Ying, Zhang Xing, Jianlin Wang 2019 Key Laboratory of Space Physics, Beijing 100076, China;

Hpc-Based Virtual Flight Test Method For Multidisciplinary Multiphysical Field Coupling, Tie Ming, Yu Ying, Zhang Xing, Jianlin Wang

Journal of System Simulation

Abstract: Multidisciplinary simulation based on virtual flight system testbed (FST) will become an alternative way for the overall performance validation of near space hypersonic vehicles (HSV). The complexity of multi-physical field coupled modeling and simulation challenges the accuracy and efficiency of virtual experiment. Therefore, a multi-physical-field coupling simulation model is established. The architecture of HPC-FST is explicitly expounded for large-scale parallel multidisciplinary virtual flight tests and multi-physics coupling simulation of whole vehicle. Moreover, an integration algorithm is developed for heterogeneous CAE models in collaborative simulation. A HPC based parallel virtual flight test method with a task-level and algorithm-level hybrid large-scale …


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