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Parallel Pattern Recognition Of Leak Current Data Using Spark-Knn, Li Li, Yongli Zhu, Yaqi Song 2019 School of Control and Computer Engineering, North China Electric Power University, Baoding 071003, China;

Parallel Pattern Recognition Of Leak Current Data Using Spark-Knn, Li Li, Yongli Zhu, Yaqi Song

Journal of System Simulation

Abstract: With the rapid development of smart grid, the status monitoring data of power grid equipment increase exponentially and gradually form the big data. Traditional computing architectures are no longer to meet the demand of computing performance. This paper explores how Spark and Cloud computing can accelerate performance of missive insulator leak current data pattern recognition. The Parallel KNN (k-Nearest Neighbor) algorithm is designed and implemented by using Spark and Aliyun E-MapReduce cloud computing platform. The results from experiments show that the performance of Spark-KNN is 2.97 times of MapReduce-KNN and gains acceleration of 8.8 times. The experimental results confirm …


Stress Distribution Formula Of Threads Casing Joint Under Symmetrical Load, Tong Hua, Xiaohong Tang, Xiaohua Zhu, He Huan, Haoran Tao 2019 1. Mechanical and Electrical Engineering of Southwest Petroleum University, Chengdu 610500, China; ;

Stress Distribution Formula Of Threads Casing Joint Under Symmetrical Load, Tong Hua, Xiaohong Tang, Xiaohua Zhu, He Huan, Haoran Tao

Journal of System Simulation

Abstract: While itis difficult tomeasure thestress distribution of casing threads underground without calculation by finite element method. Here assumes a deformation compatibility factor Ux, use an initial calculation to represent the thread stress, f(x)=f0Ux, and applythe ABAQUS finite element software to calculate the stress distribution of the threads under different symmetrical loads. Obtain the expressions of Ux by curve fitting, and get the threads stress calculation formula to provide an intuitive, fast and accurate method of calculation for the site. Providea theoretical reference for development and manufacture of casing …


Numerical Simulation Of Borehole Stability In Underbalanced Drilling Coal Seam, Yumei Li, Su Zhong, Zhang Tao, Delong Zhang, Liwei Yu, Si Na 2019 1.Beijing Key Laboratory of High Dynamic Navigation Technology, University of Beijing Information Science & Technology, Beijing 100101, China; ;

Numerical Simulation Of Borehole Stability In Underbalanced Drilling Coal Seam, Yumei Li, Su Zhong, Zhang Tao, Delong Zhang, Liwei Yu, Si Na

Journal of System Simulation

Abstract: According to the formation parameters of No.3 coal seam in the Qinshui Basin, Shanxi Province, considering the interaction between seepage and deformation in the borehole wall of coal seam, using the finite element method for establishing the stable elastoplastic numerical model of the borehole in coal seam,the variation of pore pressure near the wellbore wall with the seepage time and the effect of time delay on wellbore stability under underbalanced drilling condition were studied. The variation law of maximum displacement and maximum plastic deformation around borehole wall with bottom pressure were analyzed. The simulation results show that there …


Improvement Of Grey Target Algorithm And Its Application In Assessment Of Marine Gas Turbine, Tongqing Wang, Mei Shan, Xiaobo Li, Jiajie Liu 2019 School of System Engineering, National University of Defense Technology, Changsha 410073, China;

Improvement Of Grey Target Algorithm And Its Application In Assessment Of Marine Gas Turbine, Tongqing Wang, Mei Shan, Xiaobo Li, Jiajie Liu

Journal of System Simulation

Abstract: In the modern shipbuilding industry, gas turbines are increasingly becoming the main power supply devices for ships with their good overall performance. The assessment of their overall performance is very important in the development and introduction of gas turbines. By using the grey target theory, a comprehensive gas turbine performance evaluation model is constructed and the grey target method can easily deal with the evaluation problem which has the characteristics of "small amount of data, lean information, and uncertainty". By discussing the influence of distinguishing coefficient in the algorithm, a method for determining the value of the distinguishing coefficient …


Impact Of Attractiveness And Influence Of Information On Cascade Size Distribution, Dong Jian, Bin Chen, Liu Liang, Chuan Ai, Zhang Fang, Xiaogang Qiu 2019 National University of Defense Technology, Changsha 410073, China;

Impact Of Attractiveness And Influence Of Information On Cascade Size Distribution, Dong Jian, Bin Chen, Liu Liang, Chuan Ai, Zhang Fang, Xiaogang Qiu

Journal of System Simulation

Abstract: The distribution of the cascade size can capture the distribution of popularity of a social network. Numerous studies have shown that the cascade size distribution follows fat-tail distributions, including power-law distribution and bimodal distribution; The underlying characteristic of this highly skewed distribution lacks quantitative experimental analysis. Based on the heterogeneous stochastic information dissemination model, namely the SVRF model, this paper examines the impact of the information attractiveness and influence on the cascade size distribution through lots of computational experiments. We find that when the mean value of the information influence and attractiveness is small, the cascade sizes follow …


Simulation Analyzing For Drawing Up Methodology Of Cooperative Train Working Diagram And Route Allocation Plan, Zhou Yan 2019 Traffic Management Department, Zhejiang Police College, Hangzhou 310053, China;

Simulation Analyzing For Drawing Up Methodology Of Cooperative Train Working Diagram And Route Allocation Plan, Zhou Yan

Journal of System Simulation

Abstract: The quality of the train diagram directly affects the efficiency of the transport operation and management. Though the inadequacies of computer drawing train working diagram were reviewed, an integrated drawing up methodology of train diagram and train route allocation plan was put forward to optimize the allocation of resources, based on the interaction relationship of train diagram and train route allocation plan. On that basis, the overall state transition adjustment algorithm, which consists of the “full timetable” result and collaborative model route allocation plan, was also proposed. Finally, the prototype system framework based on .NET was described, and the …


Three-Dimensional Model Of Magnetostrictive Force Sensor Considering Stress Coupling And Experimental Research, Li Bo, Jiabin Yang, Shu Liang, Penghui Li, Wu Hong 2019 1. School of Logistics Engineering, Wuhan University of Technology, Wuhan 430063, China; ;

Three-Dimensional Model Of Magnetostrictive Force Sensor Considering Stress Coupling And Experimental Research, Li Bo, Jiabin Yang, Shu Liang, Penghui Li, Wu Hong

Journal of System Simulation

Abstract: Considering the brittleness of normal magnetostrictive and piezoelectric materials, a new magnetostrictive force sensor is proposed, in which Galfenol alloy is taken as the sensing element. Considering the anisotropy of Galfenol, three-dimensional magneto-mechanical coupled model is presented on the basis of electromagnetic and mechanical governing equation. The nonlinear magnetization behavior of Galfenol is described by employing the discrete energy-averaged model. The coupling of the magnetization model and the structural model is implemented with the PDE weak form equations. The model is solved by using the weak form module of Comsol Multiphysics. Simulation results show that both field and stress …


Design Of Fault Tolerant Control Visual Simulation System For Flying Wing Aircrafts, Shaojie Zhang, Qingkai Meng 2019 College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China;

Design Of Fault Tolerant Control Visual Simulation System For Flying Wing Aircrafts, Shaojie Zhang, Qingkai Meng

Journal of System Simulation

Abstract: A visual simulation platform based on Qt Quick was designed with respect to the simulation about fault tolerant control for flying wing aircrafts. Aircraft mathematical model and control law were developed using Simulink. Man-machine interface was developed based on Qt Quick to inject fault to Simulink model, load control law, setting up the simulation parameters and process, the interface can monitor and display graphically the key parameters to test and verify fault tolerant control laws. FlightGear visual engine was driven by MATLAB to achieve real-time visual flight simulation and the aircraft were showed in 3-D model. Baidu Map’s API …


Multi-Constraint Service Selection Based On Decomposition Of Global Qos, Fang Chen, Jindong Wang, Hengwei Zhang, Wang Na 2019 Information Engineering University, Zhengzhou 450001, China;

Multi-Constraint Service Selection Based On Decomposition Of Global Qos, Fang Chen, Jindong Wang, Hengwei Zhang, Wang Na

Journal of System Simulation

Abstract: With the rapid growth of Web services in cloud computing environment, users make new demands on dynamic service composition, that quickly selects composite service which can meet multi-constraints. According to the demand, a multi-constraint service selection method based on decomposition of global QoS was proposed. A new cultural genetic algorithm was designed to decompose the global QoS constraints, and services were filtered by combining with the functional constraints between candidate services. An adaptive replacement strategy was used to dynamically adjust QoS constraint boundaries, so as to ensure the most appropriate composite service obtained by local selection. Experimental results show …


Research On Impact Performance Of Layer-Number Of 2024 Aerospace Aluminum Alloy Immobilized Target Against Bird Strike, Jianxin Xu, Jiajun Yuan, Yunfei Deng 2019 College of Aeronautical Engineering, Civil Aviation University of China, Tianjin 300300, China;

Research On Impact Performance Of Layer-Number Of 2024 Aerospace Aluminum Alloy Immobilized Target Against Bird Strike, Jianxin Xu, Jiajun Yuan, Yunfei Deng

Journal of System Simulation

Abstract: In order to investigate the anti-penetration performance of target plate of the same thickness under different number of layers, a model of SPH(Smoothed Particle Hydrodynamics) cylindrical bird bullet to impact 2024 aerospace aluminum alloy Lagrange target is established by using the AUTODYN finite element software. The thickness of target is 1 mm, 2 mm, 3 mm and 4 mm, 1 mm and 2 mm target plate is divided into single and double, 3 mm target plate is divided into single, double and three layers, 4 mm target plate is divided into single, double and four layers. …


Fault Co-Simulation Of Fuel Regulator In A Certain Type Of Turbofan Engine, Wei Xiang, Benwei Li, Xinyi Yang, Xingbo Wang 2019 1. Aircraft Engineering, Naval Aeronautics and Astronautics University, Yantai 264001, China; ;

Fault Co-Simulation Of Fuel Regulator In A Certain Type Of Turbofan Engine, Wei Xiang, Benwei Li, Xinyi Yang, Xingbo Wang

Journal of System Simulation

Abstract: A co-simulation method for fuel regulator fault diagnosis in a certain type of turbofan engine is performed, which consists of AMEsim Model of main fuel control system and Simulink Model of aero-engine. The AMEsim Model of main fuel system and Simulink Model of aero-engine are built and their accuracy is validated by experiments and the engine’s operating data, respectively. The co-simulation model based on the main fuel control system and the aero-engine is proposed through the interface of AMEsim and Simulink software. The typical faults and obviation methods are simulated by the co-simulation model. The research shows that the …


Assessment And Verification Of Code-Carrier Coherence On Bds, Dongxia Li, Fuhan Song, Ruihua Liu 2019 College of Electronic Information and Automation, Civil Aviation University of China, Tianjin 300300, China;

Assessment And Verification Of Code-Carrier Coherence On Bds, Dongxia Li, Fuhan Song, Ruihua Liu

Journal of System Simulation

Abstract: In order to verify code-carrier coherence on BeiDou Navigation Satellite System (BDS), the monitoring and assessment system of code-carrier coherence on BDS is designed. Code-Carrier Divergence (CCD) monitor is designed to detect the anomaly status of ionosphere, and based on the detection results, ionosphere delay error is eliminated by using Divergence-Free Smoothing (DFree) or Ionosphere-Free Smoothing (IFree) separately. The values of integer ambiguity are calculated based on tri-frequency ambiguity decomposition model, and the cycle slip is detected by using tri-frequency pseudorange code and combination of carrier phase. Assessment and verification of code-carrier coherence can be conducted. It is …


Analysis And Optimization Of Mr Damper Based On Parallel Of Positive And Negative Stiffness, Yanbin Liu, Yawei Wang, Jianhai Han 2019 1. School of Mechatronics Engineering, Henan University of Science and Technology, Luoyang 471003, China; ;2. Collaborative Innovation Center of Machinery Equipment Advanced Manufacturing, Henan Province, Henan University of Science and Technology, Luoyang 471003, China;

Analysis And Optimization Of Mr Damper Based On Parallel Of Positive And Negative Stiffness, Yanbin Liu, Yawei Wang, Jianhai Han

Journal of System Simulation

Abstract: For purpose of reducing broadband vibration of precision machine tool from environment, a MR damper with squeeze mode was designed based on parallel of positive and negative stiffness. First, according to fluid continuity equation and momentum equation, the LPM (Lumped Parameter Model) was set up. Then, using two-way fluid-solid coupled nonlinear FEA (Finite Element Analysis), the flow field distribution was discussed for revealing flow characteristics of damper. Based on the LPM, the dynamic stiffness and displacement transfer rate, as well as the high-low frequency decoupling theory, were studied. Finally, multi-objective genetic algorithm was used to carry out the optimization …


Modeling And Simulating On Flow Characters Of Axial Piston Pump With Concial Cylinder Block Considering The Hydraulic Oil Containing Air, Donglin Tang, Wu Fan, Zhiquan Ma, Zhichun Zeng 2019 Southwest Petroleum University Institute of Electrical and Mechanical Engineering, Chengdu 610500, China;

Modeling And Simulating On Flow Characters Of Axial Piston Pump With Concial Cylinder Block Considering The Hydraulic Oil Containing Air, Donglin Tang, Wu Fan, Zhiquan Ma, Zhichun Zeng

Journal of System Simulation

Abstract: Aiming at the problem that air bubbles mix into hydraulic oil would affect fluid properties, and then would affect the flow characters of axial piston pump with concial cylinder block, according to the theoretical ananlysis, the generic submodel of the fluid properties and single piston/swash plate mechanism were developed by AMESet, and the simulation result verified the applicability of the fluid properties generic submodel. The model of whole pistion pump was developed by AMESim. The influences of air content in hydraulic oil and pistion dip angle on the flow characters of pistion pump were studied. The results …


Cam Of Possible Accident For Longitudinal Slope Curve Of Mountain Freeway, Mingbao Pang, Zhanghui Cai 2019 School of Civil and Transportation, Hebei University of Technology, Tianjin 300401, China;

Cam Of Possible Accident For Longitudinal Slope Curve Of Mountain Freeway, Mingbao Pang, Zhanghui Cai

Journal of System Simulation

Abstract: Based on the analysis of vehicle driving behaviors and accidents, a cellular automaton (CA) simulation model of longitudinal slope curve on mountain freeway with the possible occurrence of traffic accident was established. The model was preliminarily validated via the comparisons between the accident rates in simulation experiments and that in actual statistics for the concrete roads. The possible schemes were determined by setting the different values of road geometric linear parameters. The nonlinear behaviors of traffic flow were simulated and the accident probabilities were obtained. The relations among the accident rate and the parameters’ values were discussed. …


System Simulation Study On Influences Of Oil Price, Policy And Public Opinion On Travel, Yijun Liu, Mengwei Li, Lian Ying 2019 1. Institutes of Science and Development, Chinese Academy of Sciences, Beijing 100190, China; ;2. University of Chinese Academy of Sciences, Beijing 100190, China; ;

System Simulation Study On Influences Of Oil Price, Policy And Public Opinion On Travel, Yijun Liu, Mengwei Li, Lian Ying

Journal of System Simulation

Abstract: With the advancement of urbanization, environmental problems such as traffic congestion and automobile exhaust pollution have received widespread attention, which made it of great significance to rationally adjust and guide people to choose green travel modes to optimize the structure of consumer travel. By constructing agent-based binary and ternary consumer driving state simulation models, three measures that may affect the consumer travel, namely, oil price regulation, policy intervention and public opinion guidance are researched, in order to explore the most influential measures, and how the three measures are more suitable for guiding healthy travel and optimizing urban road conditions, …


Domain Decomposition Based Sph Parallel Computing Method Study And Its Application, Chen Hong, Huang Jie, Li Yi, Liu Sen 2019 Hypervelocity Impact Research Center, China Aerodynamics Research and Development Center, Mianyang 621000, China;

Domain Decomposition Based Sph Parallel Computing Method Study And Its Application, Chen Hong, Huang Jie, Li Yi, Liu Sen

Journal of System Simulation

Abstract: To improve the speed and the capability of large scale simulation of SPH (Smoothed particle hydrodynamics), a parallel SPH method based on dynamic domain decomposition is developed. The decomposition of arbitrary numbers of subdomains is achieved by adopting dimension based factorable method. Rapid parallel cut plane search is achieved by adopting bisection method. The data communication between compute nodes is reduced by improving the subdomain assignment. A parallel SPH program was developed based on this method, with which the process of projectile hypervelocity impacting thin plate producing debris cloud was simulated. The result shows that: the method is …


Tracking Control Method Of Autonomous Dynamic Collision Avoidance For Unmanned Surface Vehicle, Yunsheng Fan, Xiaojie Sun, Guofeng Wang, Guo Chen 2019 School of Marine Electrical Engineerin, Dalian Maritime University, Dalian 116026, China;

Tracking Control Method Of Autonomous Dynamic Collision Avoidance For Unmanned Surface Vehicle, Yunsheng Fan, Xiaojie Sun, Guofeng Wang, Guo Chen

Journal of System Simulation

Abstract: To solve the dynamic tracking control of autonomous avoidance problem of the "Lanxin" Unmanned Surface Vehicle (USV) in the unknown ocean environment, by combining the unknown dynamic collision avoidance path planning and tracking control, a dynamic tracking control of autonomous avoidance method in the unknown ocean environment is presented. In this method, in consideration of the unknown ocean environment and real time dynamic obstacle avoidance, using a dynamic obstacle avoidance algorithm based on the velocity decomposition, a dynamic autonomous avoidance controller based on USV experimental platform is designed. Simulation results show that the method is effective and accurate, …


Variable Step-Size Constrained Total Least Squares Algorithm For Space Registration, Jiaqiang Li, Chunyan Zhao, Jinli Chen, Ronghua Zhao, Yanping Zhu 2019 1. Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science & Technology, Nanjing 210044, China; ;

Variable Step-Size Constrained Total Least Squares Algorithm For Space Registration, Jiaqiang Li, Chunyan Zhao, Jinli Chen, Ronghua Zhao, Yanping Zhu

Journal of System Simulation

Abstract: To solve the problem of location inaccuracy caused by abnormal error registration, a variable step-size constrained total least squares algorithm is presented. By building a nonlinear function relationship between step size and steps, algorithm step size is relatively large in initial stage and is very small during steady state. So this algorithm can achieve faster convergence rate and smaller steady-state imbalance noise at the same time. This algorithm reduces the convergence steps and improves the stability after convergence. Therefore this algorithm reduces the impact of abnormal error registration on location result. Meanwhile, this algorithm also makes location result more …


Spatial Target Localization Using Fuzzy Square-Root Cubature Kalman Filter, Haoshen Lin, Xiaojun Yang, He Bing 2019 Rocket Force University of Engineering, Xi’an 710025, China;

Spatial Target Localization Using Fuzzy Square-Root Cubature Kalman Filter, Haoshen Lin, Xiaojun Yang, He Bing

Journal of System Simulation

Abstract: The tracking of spatial target based on bearing-only measurements belongs to the nonlinear model of serious. Uncertain statistical characteristics of noise, which is caused by complex space environment, leads to reduced accuracy of traditional methods. The fuzzy square-root cubature Kalman filter was presented (FS-CKF) by introducing the thought of fuzzy in square-root cubature Kalman filter (SCKF). The algorithm which uses trapezoid subordinate function to describe noise gets rid of the limitations of traditional methods and broadens the range of SCKF. The result of simulation shows that the convergence speed of FS-CKF was 32.52% and 18.28% faster than SCKF …


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