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Two-Dimensional Parameter Estimation Of Near Field Sources Based On Propagator Method, Caifeng Liang, Pan Jing, Liu Ying, Li Xu 2020 1. Electronic Engineering Department, Tianjin University of Technology and Education, Tianjin 300222, China;;2. School of Electronic and Information Engineering, Beijing Jiaotong University, Beijing 100044, China;

Two-Dimensional Parameter Estimation Of Near Field Sources Based On Propagator Method, Caifeng Liang, Pan Jing, Liu Ying, Li Xu

Journal of System Simulation

Abstract: A new method based on fourth-order cumulant and propagator method for the joint estimation of the range and DOA of spatial near-field sources is presented. The fourth-order cumulant matrix is constructed using the received uniform linear array data, the received signal noise subspace is estimated by propagator method; the range and DOA of spatial near-field sources are gotten through the spectrum peak search method after the MUSIC spectrum function construction. Compared with the traditional MUSIC algorithm, the presented algorithm with the propagator method directly estimates the least squares solution of the noise subspace, rather than conventional orthogonal solution of …


Dynamic Evolvement And Emergence Modeling For Distributed Operational Systems Capability, Yinghui Yang, Jianhua Li, Mingli Nan, Chen Qiang, Jifang Wen 2020 1. Information and Navigation College, Air Force Engineering University, Xi'an 710077, China;;;

Dynamic Evolvement And Emergence Modeling For Distributed Operational Systems Capability, Yinghui Yang, Jianhua Li, Mingli Nan, Chen Qiang, Jifang Wen

Journal of System Simulation

Abstract: Aiming at dynamic characteristic of battlefield environment, particularity of operational systems, function heterogeneity and nonlinear effect of operational units, a new dynamic evolvement and emergence modeling method for distributed operational systems capability was proposed. Operational systems super-network model composing of unit layer and network & system layer was built based on super-network theory, and relationship between two layers was analyzed. Concepts of unit capability, network & system capability, systematic capability and fire procedure link were defined. Unit to capability mapping relationship and capability to capability relationship were researched respectively. Affects of unit self-effect, units' inter-effect, network promotion and battlefield …


Robust Control Of Free-Floating Two-Flexible-Link Space Manipulator Based On Observer, Xiaoyan Yu, Chen Li 2020 School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou 350116, China;

Robust Control Of Free-Floating Two-Flexible-Link Space Manipulator Based On Observer, Xiaoyan Yu, Chen Li

Journal of System Simulation

Abstract: The joint motion robust control and optimal flexible vibration control of a free-floating two-flexible-link space manipulator based on linear observers was discussed. The dynamic model of a free-floating space manipulator with two flexible links was established by the momentum conservation and the Lagrange equations. Based on singular perturbation approach and choosing appropriate local coordinate frame, a slow subsystem and a flexible-link fast subsystem were obtained. The corresponding controllers were proposed for the two subsystems, which was the linear observer based robust slow subsystem controller and the linear observer based flexible link fast subsystem optimal controller. Numerical simulation demonstrates …


Research On Force Compliance Of The Hydraulic Control System In Major-Motion Mechanism For Manipulator, Geqiang Li, Jingwei Zhang, Yuesong Li, Bin Zhou, Shuye Ma 2020 1. Department of Mechanical and Electrical Engineering, Henan University of Science and Technology, Luoyang 471003, China;;

Research On Force Compliance Of The Hydraulic Control System In Major-Motion Mechanism For Manipulator, Geqiang Li, Jingwei Zhang, Yuesong Li, Bin Zhou, Shuye Ma

Journal of System Simulation

Abstract: The force compliance method of the hydraulic control system in major-motion mechanism was proposed during the forging process. Taking the major-motion mechanism of the forging manipulator as the target, the inverse kinematics model of major-motion mechanism was established, and the dynamic model of hydraulic control system was built. Through taking the pressure as the controlled variable, the model of the lifting hydraulic control system was obtained by using the co-simulation technology. Based on the principle of the horizontal buffering system, the model of the buffering hydraulic system which was made up of the buffering cylinder and the accumulator …


In-Cylinder Flow Analysis And Verification Of Opposed-Piston Two-Stroke Engine, Fukang Ma, Changlu Zhao, Zhenfeng Zhao, Wang Hao, Yu Xia, Cao Yan, Jiqing Zhang 2020 1. School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China;;2. School of Mechanical and Power Engineering, North University of China, Taiyuan 030051, China;;

In-Cylinder Flow Analysis And Verification Of Opposed-Piston Two-Stroke Engine, Fukang Ma, Changlu Zhao, Zhenfeng Zhao, Wang Hao, Yu Xia, Cao Yan, Jiqing Zhang

Journal of System Simulation

Abstract: The effects of flat piston uniform scavenging chamber, flat piston non-uniform scavenging chamber and pit piston non-uniform scavenging chamber on the in-cylinder flow were analyzed. Uniflow scavenging zero-dimensional model was used to qualitative analysis in-cylinder flow organizational process and influence rule for opposed-piston two-stroke engine. Results show that uniform scavenging chamber can organize swirl and increase scavenging efficiency and non-uniform scavenging chamber can organize tumble and increase turbulent kinetic energy. Scheme 3 is favorable to organize tumble and maintain the in-cylinder turbulence intensity, which is increased by 150 percent.


Dfig Grid Connection Simulation Method Used For Transient Analysis Of Black-Start, Liqing Liu, Zengqiang Mi, Du Ping, Yuliang Wan, Yuan He 2020 1. State Key Laboratory of Alternate Electrical Power System With Renewable Energy Sources, Baoding 071003, China;;

Dfig Grid Connection Simulation Method Used For Transient Analysis Of Black-Start, Liqing Liu, Zengqiang Mi, Du Ping, Yuliang Wan, Yuan He

Journal of System Simulation

Abstract: Establishing a grid connection model of doubly-fed induction generator based wind turbine (DFIG) could be useful in the research and verification of black-start strategy in isolated power grid containing wind power. A DFIG grid connection simulation method based on Simulink was proposed. Through analyzing the operation characteristics of doubly-fed induction generator in no-load and grid-connected conditions, its dual-operation simulation model was established. According to the grid-connection theory of DFIG, the established doubly-fed induction generator model was combined with wind turbine, converter and other built-in modules, and the DFIG grid connection model was built with its control system added. …


Eigen-Value Combination Approach For Speech Enhancement, Huijuan Lu, Yaqing Liu, Yanqiu Liu, Guan Wei 2020 1. College of Information Engineering, China Jiliang University, Hangzhou 310018, China;;

Eigen-Value Combination Approach For Speech Enhancement, Huijuan Lu, Yaqing Liu, Yanqiu Liu, Guan Wei

Journal of System Simulation

Abstract: In order to further suppress noise, a kind of speech enhancement algorithm based on Eigen-value merge was proposed. Eigen-values combination was used to improve the speech quality on the basis of the classic embedded pre-whitening subspace methods. The study shows that, after decomposing the covariance matrix of speech signals with noise, the larger Eigen-value component mainly includes speech information, and the smaller Eigen-value component mainly contains noise. Sorted by Eigen-values from small to big, the adjacent large Eigen-value component replaces with small Eigen-value component, which can effectively suppress noise and improve the quality of speech. Compared with other speech …


Gm-Cphd Filter With State-Dependent Clutter, Lili Ma, Xiaoshan Qin, Jinguang Chen 2020 School of Computer Science, Xi'an Polytechnic University, Xi'an 710048, China;

Gm-Cphd Filter With State-Dependent Clutter, Lili Ma, Xiaoshan Qin, Jinguang Chen

Journal of System Simulation

Abstract: For many sensors the clutters observed are easier to concentrate in the area around targets, namely the state-dependent clutter, which is different from the known clutter distribution in traditional filtering algorithms. So, the accuracy the real-time performance and of traditional multi-target tracking will be greatly degraded. To solve this problem, a kind of GM-CPHD filter with state-dependent clutter was proposed. The relationship between clutter and state was modeled. The clutter intensity was recalculated according to the distribution of clutter in the whole surveillance area and applied to update process; at the same time, in order to reduce the time …


Research On Static Behavior Of Xx-Joints Based On Ansys, Pan Ying, Linxiao Qin 2020 1. College of Mechanical Engineering, Shanghai University of Engineering Science, Shanghai 201620, China;;

Research On Static Behavior Of Xx-Joints Based On Ansys, Pan Ying, Linxiao Qin

Journal of System Simulation

Abstract: Nonlinear finite element analysis was used in the ultimate bearing capacity on planar XX-joints by ANSYS software. The stress distributions of the joints were demonstrated, the main failure modes of the joints were determined, and the influences of some fundamental geometric parameters on the ultimate strength were the research points. The results show β (diameter ratio of the branch to the chord), θ (axial angle of the chord and the branch), γ (the ratio of the diameter of the chord to the thickness of the walls of the chord) are the main …


Research Of Impact Point Accuracy Of One-Dimensional Trajectory Correction Projectile Based On Monte Carlo, Xiaoyun Lei, Zhian Zhang 2020 ZNDY of Ministerial Key Laboratory, NUST, Nanjing 210094, China;

Research Of Impact Point Accuracy Of One-Dimensional Trajectory Correction Projectile Based On Monte Carlo, Xiaoyun Lei, Zhian Zhang

Journal of System Simulation

Abstract: After the one-dimensional trajectory correction projectile out of the muzzle, various disturbance factors caused the impact point dispersion. Monte Carlo method was utilized on the shooting accuracy analysis. Based on the practical test datasets, three major factors were determined, namely, time delay of opening-damper mechanism, error of drag coefficient and measurement error of target. As to the disturbances, function randn was used for the analysis of the three major factors on the flat of Matlab. According to error distribution of the factors, the probability distribution and dispersion of the impact point were obtained. The maximum and minimum ranges of …


Potato Storage Temperature Prediction Control Based On Pso And Esns, Junxia Liu, Xinrong Xiong, Hu Bing 2020 1. Department of Electrical and Information, Xinjiang Institute of Engineering, Urumqi 830023, China;;2. School of Information Science and Engineering, Xinjiang University, Urumqi 830046 China;

Potato Storage Temperature Prediction Control Based On Pso And Esns, Junxia Liu, Xinrong Xiong, Hu Bing

Journal of System Simulation

Abstract: According to the current situation of potato storage and serious waste of raw materials and human resources of potato processing enterprises, combined with temperature data characteristics of potato storage from Xinjiang Great Russell Agricultural Science and Technology Development LTD., and control effect of the conventional control methods which is not ideal, a new temperature predictive control method was proposed, which rolled to optimize the input control variable by using particle swarm optimization algorithm and get the actual output values, use ESNs to forecast the temperature in the storage, the system was corrected by deviation between forecasting output and actual …


Research On Intelligent Hauling Speed Regulation System Based On Shearer's Reliability, Xunan Liu, Lijua Zhao, Dongmin Gai, Zhangyu Du, Liangying Hao 2020 College of Mechanical Engineering, Liaoning Technical University, Fuxin 123000, China;

Research On Intelligent Hauling Speed Regulation System Based On Shearer's Reliability, Xunan Liu, Lijua Zhao, Dongmin Gai, Zhangyu Du, Liangying Hao

Journal of System Simulation

Abstract: Under the mine, Shearer's hauling speed affected the shearer's efficiency and reliability. Taking MG32570*2/325-BWD shearer as research object, from shearer's reliability, by using Simulink, the intelligent speed regulation system was established, based on shearer key parts' reliability. The building & simulation of hauling motor load torque block and recommended optimum hauling speed generation block which was fitted by neural network was solved. The simulation results show that: this system can achieve the recommended speed, which is traced by hauling speed rapidly and accurately. When consistent coefficient and cutting depth are 2.85 and 0.58m, the hauling motor's maximum speed is …


Multipurpose Image Watermarking Algorithm For Progressive Transmission, Jianqiu Jin, Bangqing Cao, Wang Xun, Haiyan Wu, Bailing Yang 2020 1. School of Computer Information and Engineer, Zhejiang Gongshang University, Hangzhou 310018, China;;

Multipurpose Image Watermarking Algorithm For Progressive Transmission, Jianqiu Jin, Bangqing Cao, Wang Xun, Haiyan Wu, Bailing Yang

Journal of System Simulation

Abstract: Multipurpose watermarking, which has the property of both robust and semi-fragile watermarking, can realize two or more purposes in one algorithm, e.g. copyright protection and content authentication usually. It can be classified into multi-segment and single-segment watermark embedding. The latter is better in invisibility, but more challenging than the former. A multi-purpose image watermarking algorithm with single-segment watermark embedding for progressive transmission was proposed. It embedded a watermark abstracted from original image into middle and low-frequency coefficients of block DCT transform. In the watermark embedding process, the intensity of watermark could be dynamically adjusted according to the local texture …


Carrier Disposition Pwm Control With No Dead Zone For Tnpc Inverter, Wenjuan Li, Feng Jie, Wang Chao 2020 School of Electric and Electronic Engineering, Harbin University of Science and Technology, Harbin 150080, China;

Carrier Disposition Pwm Control With No Dead Zone For Tnpc Inverter, Wenjuan Li, Feng Jie, Wang Chao

Journal of System Simulation

Abstract: After the addition of dead zone, the carrier disposition PWM modulation method could have some problems, such as distortion of current waveform and decreasing of voltage utilization ratio. Taking the TNPC type three-level inverter as a researching object, a novel method of the carrier disposition PWM modulation with no dead zone for three-level inverter was proposed, in which three PWM modulation signals were generated by using triple carrier wave. By analyzing the effect caused by the dead zone in different operating states, on and off rules of power switches were derived. Simulation results in MATLAB/Simulink environment show that the …


Motion Reconstruction And Simulation Using Sparse Inertial Sensors, Lijun Cui, Tianyu Huang, Feng Feng, Zhang Jie, Yang Kai, Liu Dong 2020 1. School of Software, Beijing Institute of Technology, Beijing 100081, China;;

Motion Reconstruction And Simulation Using Sparse Inertial Sensors, Lijun Cui, Tianyu Huang, Feng Feng, Zhang Jie, Yang Kai, Liu Dong

Journal of System Simulation

Abstract: A method was proposed to reconstruct high-dimensional full-body motion sequences from low-dimensional control data collected by sparse inertial sensors. The approach solved the mapping problem from low dimension to high dimension. A numerical similarity- geometrical similarity-time continuity model was setup to ensure the reconstructed motion candidates in numerical-logical similarity. The gap between angle and angular acceleration was eliminated by acceleration reconstruction. An energy function was introduced to optimize the reconstructed results which guaranteed the accuracy. The analysis and comparison experiments show that the proposed method can reconstruct nature and credible motions in real-time and can be applied …


Business Process Modeling Algorithm Based On Ontology Language, Huang Ying, Kangshun Li, Li Wei, Keqing He 2020 1. State Key Laboratory of Software Engineering, School of Computer, Wuhan University, Wuhan 430072, China;;2. Institute of Mathematical and Computer Sciences, Gannan Normal University, Ganzhou 341000, China;;

Business Process Modeling Algorithm Based On Ontology Language, Huang Ying, Kangshun Li, Li Wei, Keqing He

Journal of System Simulation

Abstract: In the view of problem in lack of information sharing mechanisms at the semantic level among processes, a business process modeling algorithm based on ontology language using concept hierarchy as background knowledge was proposed. The business process modeling by traditional business process languages can be transferred to ontology language (OWL) description so as to realize the semantic sharing of business process. The approach has two main advantages compared with traditional methods: (1) accelerating the building process, minimizing the conversion cost; (2) background knowledge guides the extraction of knowledge resided in database. As a way of validating the approach, part …


Measurement Error Correction Model Of Tof Depth Camera, Le Wang, Luo Yu, Haikuan Wang, Minru Fei 2020 Shanghai Key Laboratory of Power Station Automation Technology, School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200072, China;

Measurement Error Correction Model Of Tof Depth Camera, Le Wang, Luo Yu, Haikuan Wang, Minru Fei

Journal of System Simulation

Abstract: 3D data intuitively reflects the full view of the target or scene. Time of Flight (ToF) camera is a range imaging sensor that can provide 3D geometric information of targets immediately, thus it is widely applied in the robot positioning and navigation, 3D reconstruction and other aspects etc. Due to the operational principle of the camera itself, there are variety measurement errors of the source data obtained by ToF, resulting in image distortion. The measurement errors in the imaging process of ToF camera were analyzed and summarized, and the cubic spline interpolation method combined with look-up table was proposed …


Modeling Of Spectrum Sensing Energy Consumption In Cognitive Radio Networks, Ziru Cui, Peng Yi 2020 Faculty of Information Engineering and Automation, Kunming University of Science and Technology, Kunming 650500, China;

Modeling Of Spectrum Sensing Energy Consumption In Cognitive Radio Networks, Ziru Cui, Peng Yi

Journal of System Simulation

Abstract: In cognitive radio networks, the energy consumption in the process of spectrum sensing is the hot spot of research. A unified framework for modeling based on Poisson process was developed which could be used even under interference limited to count the energy consumption, thereby obtaining a spectrum sensing energy consumption. Spectrum sensing energy as the function of the number of secondary users in cognitive radio networks, their spatial density and the number of hops, could be modelled as a truncated gamma distribution. This model is used to statistically analyze cognitive users' energy consumption in the process of spectrum sensing …


Sliding Mode Auto - Disturbance Rejection Control Of Hypersonic Vehicle Under Disturbance, Mingzhi Cheng, Yunjie Wu, Ma Fei 2020 1. School of Automation Science and Electrical Engineering, Beihang University, Beijing 100191, China;;2. State Key Laboratory of Virtual Reality Technology and Systems, Beihang University, Beijing 100191, China;;3. Key Laboratory of Aircraft Control Integration Technology, Beijing 100191, China;

Sliding Mode Auto - Disturbance Rejection Control Of Hypersonic Vehicle Under Disturbance, Mingzhi Cheng, Yunjie Wu, Ma Fei

Journal of System Simulation

Abstract: The strong coupling of the hypersonic vehicle, the high order of the model, and the perturbation of the aerodynamic parameters make it difficult for the general controller to achieve the desired control effect. The self-disturbing tandem technique can well meet the requirements of the high-order model control. The use of sliding mode variable structure technology which is not sensitive to perturbation of parameters can enhance the system immunity. The simulation results show that the control effect is very good.


Complexity Analysis Of Joint Operational Network Information System, Peng Jun, Mingzhi Zhang 2020 The Department of Information Operation& Command Training, National Defense University, Beijing 100091, China;

Complexity Analysis Of Joint Operational Network Information System, Peng Jun, Mingzhi Zhang

Journal of System Simulation

Abstract: Based on the theory of complex networks, the structure and characteristics of joint operational network information system (JONIS) were analyzed from the perspectives of heterogeneous directional weighted network topology, strong degree and its centralities. It is found that the combat network based on JONIS has characteristics of small-world and scale-free, with a large average weighted aggregation coefficient and a small average weighted path length, showing a similar power-law distribution. In the example network, command centers, satellites, support force, and early warning unit all have larger strong degrees and centralities. These platforms as the center of gravity and fragile nodes …


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