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Robust Steerable Frequency Invariant Beamformer Design Based On Srv-Cls, Suting Chen, Zhang Wei 2020 1. Jiangsu Province Key Laboratory of Meteorological Observation and Information Processing in Nanjing University of Information Science & Technology, Nanjing 210044, China;;2. Atmospheric Environment and Equipment Technology Synergy Innovation Center, Nanjing 210044, China;

Robust Steerable Frequency Invariant Beamformer Design Based On Srv-Cls, Suting Chen, Zhang Wei

Journal of System Simulation

Abstract: The frequency invariant beamformer (FIB) has important applications in wideband array signal processing. Conventional FIB design approaches are usually proposed without considering the mismatches in microphone array characteristic, which leads to the performance of the FIBs degrading in practical applications. Therefore, a robust steerable frequency invariant beamformer design approach based on spatial response variation constrained least squares (SRV-CLS) was proposed. It combined the SRV-CLS FIB design approach with classical robust beamforming algorithm, and added the microphone characteristics as robust favor in the cost function. The proposed approach could work well in the presence of microphone mismatches, ensured the frequency …


Dynamic Arrival Sequencing & Scheduling Based On Branch & Bound Algorithm, Junfeng Zhang, Wang Fei, Tengteng Ge 2020 School of Civil Aviation, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China;

Dynamic Arrival Sequencing & Scheduling Based On Branch & Bound Algorithm, Junfeng Zhang, Wang Fei, Tengteng Ge

Journal of System Simulation

Abstract: Optimization of arrival sequencing and scheduling is not only the prerequisite for properly allocating and fully utilizing the runway resource, but also the fundamental element for improving terminal operation efficiency. Dynamic arrival sequencing was obtained by time-triggered sliding time window method. On the basis of accurate 4D trajectory prediction, branch and bound algorithm was adopted to generate an optimal sequence, combined with the actual operation constraints. Taking Shanghai Pudong Airport as an example for simulation, the optimization results were compared with the actual landing time and simulation results based on first come first serve strategy. The results indicate that …


Simulation Study On External Explode Of Large Equivalent Charge On Large Buildings, Weiping Zhao, Xiankun Ge, Chuanwu Liu, Fengchun Zhu 2020 1. The Chinese People's Liberation Army 95856, Nanjing 210028, China;;

Simulation Study On External Explode Of Large Equivalent Charge On Large Buildings, Weiping Zhao, Xiankun Ge, Chuanwu Liu, Fengchun Zhu

Journal of System Simulation

Abstract: The particle algorithm in AUTODYN, Smoothed Particle Hydrodynamics (SPH), was used to simulate dynamic damage of the external explosion on large buildings, which provided a visual effect. The dynamic damage details of reinforced concrete and brick masonry structure at different time were proposed by the simulation of single component. Additionally, the overpressure of shock wave, caving velocity and kinetic energy were obtained. It shows that the caving can speed up to a maximum value of 152 m/s with the kinetic energy of 18 000 J, that means a great damage to personnel and equipment in the building. Under …


Study Of Cognitive Model For Survivable System Based On High-Order Multi-Type Π Calculus, Guosheng Zhao, Zhang Nan, Wang Jian 2020 1. College of Computer Science and Information Engineering, Harbin Normal University, Harbin 150025, China;;

Study Of Cognitive Model For Survivable System Based On High-Order Multi-Type Π Calculus, Guosheng Zhao, Zhang Nan, Wang Jian

Journal of System Simulation

Abstract: A cognitive model for survivable system with a multilayer cognitive ability was proposed, and based on high-order multi-type π calculus, combining formal modeling of cognitive model with quantitative analysis of cognitive performance, thus can obtain the quantitative evaluation of system cognitive performance after formal modeling of system operation state, system service and internal structure. A cognitive model for survivable system with a multilayer cognitive ability was proposed. Based on high-order multi-type π calculus, formal modeling of cognitive model for survivable system in two aspects was taken. By using the tool MWB, the tests were achieved about system availability, instantaneous …


Research On Direct Torque Control Of Induction Motor Based On Svpwm, Yougui Guo, Dongqing Pan, Deng Cheng, Li Hui, Wenlang Deng 2020 Institute of Information and Engineering of Xiangtan University, Xiangtan 411105, China;

Research On Direct Torque Control Of Induction Motor Based On Svpwm, Yougui Guo, Dongqing Pan, Deng Cheng, Li Hui, Wenlang Deng

Journal of System Simulation

Abstract: The traditional direct torque control of induction motor directly controls the flux and torque through hysteresis comparator, which leads to problems such as limited voltage control vectors, large flux and torque ripple. To solve the problems, adopting SVPWM-DTC, a direct toque control (DTC) method based on space vector pulse width modulation (SVPWM) was verified with a simulation. The results show that this method can improve the performances of DTC system efficiently and maintain the switch frequency constant at the same time. A practical application used in variable speed constant frequency double-fed wind power system was proposed, in which the …


Study Of Light Extraction Efficiency For Thin-Film-Flip-Chip Light-Emitting Diodes With Periodic Spheroids, Xiaojie Yu, Li Kang, Fanmin Kong, Qingyang Yue 2020 School of Information Science and Engineering, Shandong University, Jinan 250100, China;

Study Of Light Extraction Efficiency For Thin-Film-Flip-Chip Light-Emitting Diodes With Periodic Spheroids, Xiaojie Yu, Li Kang, Fanmin Kong, Qingyang Yue

Journal of System Simulation

Abstract: The enhancement of light extraction efficiency for thin-film-flip-chip light-emitting diodes (LED) based gallium nitride (GaN) with triangular lattice periodic ellipsoid was studied. Three dimensional finite difference time domain methods (3D-FDTD) were applied to analyze the structural parameters (the period and ellipsoid height) effects on thin-film-flip-chip LED light extraction efficiency. FDTD numerical results prove that ellipsoids structure can improve LED light extraction efficiency and impair guide mode. Method rigorous coupled wave (RCWA) is adopted to analyze diffraction characteristics. This research results show that optimization of the periodic ellipsoid can improve thin-film-flip-chip LED light extraction efficiency increased by 2.8 times.


Prediction Of Energy Efficiency Of Nc Machine Tools Based On Recursive Method With Discounted Measurements, Cai Lei, Wang Yan, Zhicheng Ji 2020 Institute of Electrical Automation, Jiangnan University, Wuxi 214122, China;

Prediction Of Energy Efficiency Of Nc Machine Tools Based On Recursive Method With Discounted Measurements, Cai Lei, Wang Yan, Zhicheng Ji

Journal of System Simulation

Abstract: Aiming at the problem that the energy efficiency of numerical control machine tool is difficult to obtain directly, a new method combined with the recursive method with discounted measurements was presented to predict the energy efficiency of machine tool. The estimation model of the cutting power was given in view of the power balance equation of the machine tool main drive system and the additional load loss function, further taking into account the additional load loss coefficients in model could not be directly measured, the recursive method with discounted measurements was adopted to identify the additional load loss coefficients …


Invasive Weed Optimization Algorithm Combined With Chaotic Mutation And Analysis Of Its Property, Huang Xia, Chunming Ye, Cao Lei 2020 1. Business School, University of Shanghai for Science and Technology, Shanghai 200093, China;;2. Zhangjiagang Campus, Jiangsu University of Science and Technology, Zhangjiagang 215600, China;

Invasive Weed Optimization Algorithm Combined With Chaotic Mutation And Analysis Of Its Property, Huang Xia, Chunming Ye, Cao Lei

Journal of System Simulation

Abstract: Inspired by the reproductive aggressive behavior of weeds in nature, invasive weed optimization algorithm (IWO) was developed as a novel bionic swarm intelligence optimization algorithm. An improved IWO algorithm was proposed on the basis of analyzing bionic principle and limitations of basic IWO, which applied an initialization strategy based on chaotic opposition-based learning, increased the diversity of the population through the mutation operator, and enhanced its ability to jump out of local optimal value by chaotic search around current elites. Simulation results for benchmark functions show that the proposed algorithm has improved optimization property compared with IWO, as an …


Cooperative Controller Design For Redundant Dual Arm Robot, Meiling Wang, Minzhou Luo 2020 1. Department of Automation, University of Science and Technology of China, Hefei 230026, China;;2. Institute of Advanced Manufacturing Technology Hefei Institute of Physical Science, Chinese Academy of Sciences, Changzhou 213164, China;

Cooperative Controller Design For Redundant Dual Arm Robot, Meiling Wang, Minzhou Luo

Journal of System Simulation

Abstract: Cooperative operation for a redundant dual arm robot can be divided into three modes, namely, independent mode, full constrained cooperative working mode and partly constrained cooperative working mode. The dynamic equations of both dual arms and the interactions between dual arms and the operating objects were established and derived based on the three modes, and a unified formulation was obtained. With focus on motion and force of the desired task being operated, a unified controller was designed which could be carried out based on two dynamic model based controllers, namely feedforward controller and computer torque controller. Simulations of dual …


Modeling And Motion Analysis Of Multi-Bodies Dynamic Of Unmaned Parafoil Vehicle, Zhang Hao, Zili Chen, Jingang Qiu 2020 Department of UAV Engineering, Ordnance Engineering College, Shijiazhuang 050003, China;

Modeling And Motion Analysis Of Multi-Bodies Dynamic Of Unmaned Parafoil Vehicle, Zhang Hao, Zili Chen, Jingang Qiu

Journal of System Simulation

Abstract: Unmanned Parafoil Vehicle (UPV) has gradually become a hotspot in the flexible wing vehicle research filed for its superior fight performance and advantages in application. An eight degrees of freedom (DOF) nonlinear dynamic model of UPV in mechanism law was proposed, aiming at the structure characteristics of the two flexible connections, and considering the added mass of canopy and the relative motion of two bodies. The response of model to different levels of thrust changes was simulated and analyzed, pulling a single steering line and pulling the left and right steering lines of canopy symmetrically on the steady state …


Wood Structure Nondestructive Detection Based On Singular Spectrum Analysis And Svm, Guoxiong Zhou, Aibin Chen, Xianyan Zhou 2020 1. School of Electricity & information Engineering, Central South University of Forestry & Technology, Changsha 410004, China;;

Wood Structure Nondestructive Detection Based On Singular Spectrum Analysis And Svm, Guoxiong Zhou, Aibin Chen, Xianyan Zhou

Journal of System Simulation

Abstract: In view of unknown defect of wood component defect, a method of wood structure nondestructive recognition based on Singular spectrum analysis and SVM was proposed. The wood specimen was tested to obtain the test signal by ultrasonic testing instrument. In order to eliminate the testing effect of the tester gain control and defect size, angle variation on the test defect echo amplitude, the abnormal fluctuation was to filter and characteristic of the original signal was extracted by singular spectrum analysis, and SVM could train the parameters and distinguish the wood defects. Simulation results show that the proposed method …


Analysis And Simulation Of A Class Of Time-Varying Wireless Networked Control Systems, Weihua Deng, Minrui Fei 2020 1. College of Electrical Engineering Shanghai University of Electric Power, Shanghai 200090, China;;

Analysis And Simulation Of A Class Of Time-Varying Wireless Networked Control Systems, Weihua Deng, Minrui Fei

Journal of System Simulation

Abstract: The problem of stabilization was investigated for a class of discrete time-varying systems over a physical IEEE 802.11b wireless channel. The wireless network-induced delays were characterized by an inverse Gaussian distribution model (IGDM) and the time-varying nature was depicted by uncertain parameter model. The model-based state feedback controller was designed to compensate the influence of delays and time-varying nature. And the stochastic stabilisability of discrete time-varying networked control system was analyzed and the solution of controller was given in the form of linear matrix inequalities (LMIs). The effectiveness of the proposed methods was illustrated by numerical simulation examples.


Cellular Automata Model Of Non-Motor Vehicle Flow Considering Reverse Vehicles, Xianyan Kuang, Weihua Cao, Wu Yun 2020 School of Electrical Engineering and Automation, Jiangxi University of Science and Technology, Ganzhou 341000, China;

Cellular Automata Model Of Non-Motor Vehicle Flow Considering Reverse Vehicles, Xianyan Kuang, Weihua Cao, Wu Yun

Journal of System Simulation

Abstract: The phenomenon of non-motor vehicle reverse driving in one-way non-motor vehicle road occurs in most China's cities. A cellular automata model of non-motor vehicle flow mixed with reverse driving vehicles was established, which considered the different lane-changing rules of the reverse and forward vehicle. The results of the computer numerical simulation for the model show that, in low density stage, the ratio of reverse vehicles has little effect on flow and speed, and the capacity and the avenge speed decrease as the ratio of reverse vehicles increases. Lane-changing ratio has a great influence on the mixed non-motor vehicles …


General Modeling Method Of Aircraft Constant-Altitude Flight, Xiaowen Duan, Xiaoguang Gao, Li Bo 2020 School of Electronic and Information, Northwestern Polytechnical University, Xi'an 710129, China;

General Modeling Method Of Aircraft Constant-Altitude Flight, Xiaowen Duan, Xiaoguang Gao, Li Bo

Journal of System Simulation

Abstract: An algorithm for the aircraft constant-altitude long-distance flight consider earth curvature studied. The required overload was calculated using the error between the real position and the ideal trajectory for two basic long-distance flight styles, i.e. great circle flight and circular flight, the simulation model of the two basic constant-altitude flight styles was established. On this basis, taking the modeling of constant-altitude box maneuvering and 8-shape constant-altitude flight as an example, the modeling process of constant-altitude combined model was studied. The simulation result shows the constant-altitude flight model can be widely used, easily implemented and easily expanded. Meanwhile, the model …


Signaling Game Analysis And Simulation On Network Decoy Defense Strategies, Leyi Shi, Junnan Zhao, Li Qin, Wen Xiao, Liu Xin 2020 College of Computer and Communication Engineering, China University of Petroleum, Qingdao 266580, China;

Signaling Game Analysis And Simulation On Network Decoy Defense Strategies, Leyi Shi, Junnan Zhao, Li Qin, Wen Xiao, Liu Xin

Journal of System Simulation

Abstract: The network decoy confrontation is regarded as a kind of observable behavior of a multi-stage signaling game. Four types of gaming models for decoy confrontation process were constructed step by step using signaling game theory, i.e. the normal service, the mixed system of normal service and honeypot, the mixed system with two kinds of signaling, and the mixed system with two kinds of signaling and three actions. In these signaling game models, the server sent a normal signaling or honeypot signaling as the sender, while the attacker chose to access, give up or access in condition as the …


Research And Simulation On Trajectory Control Of Telescopic Boom Aerial Work Platform For Hull Spray Painting, Wang Xin, Lingchong Gao, Zhaoqiu Huang, Yuchen Xiao 2020 1. School of Mechanical Engineering, Dalian University of Technology, Dalian 116023, China;;

Research And Simulation On Trajectory Control Of Telescopic Boom Aerial Work Platform For Hull Spray Painting, Wang Xin, Lingchong Gao, Zhaoqiu Huang, Yuchen Xiao

Journal of System Simulation

Abstract: Telescopic boom aerial work platform, which has been widely applied in ship building field, is taken as research object. An intelligent method of spray painting, continuous spray painting along hull's contour was proposed. Correspondence between position vector of boom's top and drive-space vector was established. A path planning strategy of continuous spray painting was designed, and the variation of driving-space vector was acquired when the path was known. The trajectory control system of intelligent spray painting was modeled in Simulink environment based on the transfer function of electro-hydraulic proportional position control system. The correction link made of …


Modeling And Simulation Of Multi-Nozzle Ejector Based On Flowmaster, Lan Jiang, Zhu Lei, Jingquan Zhao 2020 School of Aeronautic Science and Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100191, China;

Modeling And Simulation Of Multi-Nozzle Ejector Based On Flowmaster, Lan Jiang, Zhu Lei, Jingquan Zhao

Journal of System Simulation

Abstract: A mathematical model of multi-nozzle ejector was established according to the mass conservation, energy conservation and momentum conservation, and a modification was achieved with the introduction of momentum correction coefficient and discharge coefficient. On this basis, linear coefficients used in the fluid network method were determined, then a system-level simulation model of multi-nozzle ejector was first developed with C# language on the fluid system simulation software of Flowmaster. The simulation and experimental results of the multi-nozzle ejector in an aircraft environmental control system shows that the entrainment ratio decreases with the increasing pressure ratio of primary and secondary flow. …


Evaluation Method Of Training Simulation Result Based On Grey Clustering And Analytic Hierarchy Process, Zhaobin Wu, Chen Li, Chunxia Zhao 2020 1. Computer Department of Nanjing University of Science and Technology, Nanjing 210094, China;;2. Unit 63961 PLA, Beijing 100012, China;;

Evaluation Method Of Training Simulation Result Based On Grey Clustering And Analytic Hierarchy Process, Zhaobin Wu, Chen Li, Chunxia Zhao

Journal of System Simulation

Abstract: An evaluation method based on grey relational analytic hierarchy process was proposed in order to improve rationality of evaluation training result of portable anti-air missile training simulation system. The evaluating indicators including definitions and calculation equations were proposed from three aspects including accuracy, rapidity and stationarity. The weights of the evaluating indicators were calculated by analytic hierarchy process of multiple experts, and the scores of the evaluating indicators were given by 0-1 process and grey clustering evaluation, and using the weights and scores of the evaluating indicators the training score could be obtained. An example of evaluation training result …


Simulation And Optimization For Bulk Terminal Yard Scheduling, Dongbo Hu, Li Pan, Binbin Zhang, Guozhi Liang 2020 1. Management School, Jinan University, Guangzhou 510632, China;;

Simulation And Optimization For Bulk Terminal Yard Scheduling, Dongbo Hu, Li Pan, Binbin Zhang, Guozhi Liang

Journal of System Simulation

Abstract: Yard is the central part of the operation process of the whole terminal. In fact, the operation of lots of bulk terminal is unscientific, which severely restricts the turnover efficiency and the throughput of the terminal. Taking the coal terminal as an example and based on its operation process, the dispatching simulation model involving all parts of the operation was established and the rules of use of the yard grids was brought forward. By optimizing the operation strategy and related parameters, it is significant to improve the input quantity of bulk terminal and the turnover efficiency.


Simulation On Aircraft Infrared Exposed Range And Detection Probability, Yunfei Zhang, Mengyue Hu, Dexiong Lai, Gengjun Ma 2020 1. School of Aeronautic Science and Engineering, Beihang University, Beijing 100191, China;;

Simulation On Aircraft Infrared Exposed Range And Detection Probability, Yunfei Zhang, Mengyue Hu, Dexiong Lai, Gengjun Ma

Journal of System Simulation

Abstract: According to the infrared-detector operating range equation, the method used to simulate the infrared detection probability and exposure of an aircraft was established, with the use of atmospheric transmission rate calculation method, the critical radiation strength calculation method and the detection probability calculation method. The physical meaning of the exposed range was analyzed, and an infrared detection simulation system was established. The system could be used to assess the infrared stealth performance of an aircraft, which includes the curve of detection probability and the curve of exposed range, giving the flight route and the infrared radiation intensity distribution of …


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