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Novel Algorithm Of High-Speed Target Isar Imaging Based On Stretch Method, Wenmao Luo, Yingliu Cui 2020 1. Department of Telecommunication, Nanjing College of Information Technology, Nanjing 210023, China;;

Novel Algorithm Of High-Speed Target Isar Imaging Based On Stretch Method, Wenmao Luo, Yingliu Cui

Journal of System Simulation

Abstract: The pulse compression result will be distorted while the target moves very fast and it cannot get right ISAR images. A novel algorithm based on chirp-Fourier transform was proposed to solve this problem. In the scheme, every echo’s differential frequency signal of stretch processing was calculated by chirp-Fourier transform to estimate the target’s location and speed, and the target’s precious speed could be averaged by the estimations during the whole dwell time. Then the penalty function could be constructed to eliminate the intra and inter-pulse motion, and it could get right ISAR images. Because the chirp-Fourier transform was …


Design And Realization Of Radar Warning Receiver Modeling System, Limin Liu, Cheng Cheng, Zhuangzhi Han 2020 Department of Electronical and Optical Engineering, Ordnance Engineering College, Shijiazhuang 050003, China;

Design And Realization Of Radar Warning Receiver Modeling System, Limin Liu, Cheng Cheng, Zhuangzhi Han

Journal of System Simulation

Abstract: According to the structure of the mainstream modern airborne radar warning receiver, a modeling method of radar warning receiver simulation system was proposed, and it realized by SystemVue. The system consists of radar signal interception, parameter estimation and signal sorting, and pulse description words can be obtained at last. The application of sorting method based on detection of single source point in the system improves the robustness. Simulation results verify the scheme feasibility.


Robust Flexible Job Shop Scheduling Method With Machine Breakdowns, Guohui Zhang, Lihui Wu, Nie Li, Yongcheng Wang 2020 1. School of Management Engineering, Zhengzhou Institute of Aeronautical Industry Management, Zhengzhou 450015, China;;

Robust Flexible Job Shop Scheduling Method With Machine Breakdowns, Guohui Zhang, Lihui Wu, Nie Li, Yongcheng Wang

Journal of System Simulation

Abstract: There are many uncertain events in the actual production process of flexible job shop, which affect the normal production and scheduling to achieve objective. According to the factor of the machine breakdown, two robustness measures combined with flexible job shop scheduling characteristics were proposed. One is considered as the initial schedule and the actual schedule makespan deviation, the other one is considered as each machine idle time and work load. The genetic algorithm was used to solve the problem, and the two parts chromosome coding was designed to avoid generating the illegal solution. Through the establishment of the probability …


Single Sign-On Model Based On Trusted-Daa Connection, Xiaohui Yang, Lijun Jiang, Wang Hong, Siyuan Chang 2020 Institute of Network Technology, Hebei University, Baoding 071002, China;

Single Sign-On Model Based On Trusted-Daa Connection, Xiaohui Yang, Lijun Jiang, Wang Hong, Siyuan Chang

Journal of System Simulation

Abstract: Traditional single sign-on (SSO) models adopt SSL connections in the cloud computing environments, while there exist several problems such as certificates cannot be updated in time, certificate updating needs a third party CA, etc.. To solve above problems, TPM was introduced between cloud identity providers and cloud service providers, and a trusted DAA connection (T-D-SSL) was designed by adopting the DAA authentication method to implementation cross platform trusted authentication, secure channel establishment, and certificate updating operation. Combining with T-D-SSL, SAML2.0, and ID-FF1.2, a new SSO model of the cloud computing environments was proposed, which could make sure the system …


Simulation Research On Model Parameter Identification Based On Prediction Error, Hongquan Wu, He Chi, Zhang Ping, Shuen Wang, Hongqiang Wei, Chu Jin, Zhang Peng 2020 Troops 63863 of PLA, Baicheng 137001, China;

Simulation Research On Model Parameter Identification Based On Prediction Error, Hongquan Wu, He Chi, Zhang Ping, Shuen Wang, Hongqiang Wei, Chu Jin, Zhang Peng

Journal of System Simulation

Abstract: Parametric differential method is often used to extract resistance coefficient in the process of trajectory simulation research for aerial bomb. The method exists following problems: high precise original data required and influenced by measurement error easily, which would cause serious error in identification result and even lead to the radiation during identification. In order to solve these problems, a method of extracting resistance coefficient based on prediction error was modeled. While coordinate was used as observations, simulation research of model parameter identification was carried out for some bomb. Precision of calculation for two models was calculated and analyzed …


Power Modeling And Simulation For D/A Network In R-C Hybrid Sar Adc, Xingyuan Tong, Zhang Yang 2020 School of Electronic Engineering, Xi'an Univ. of Posts & Telecommunications, Xi'an 710121, China;

Power Modeling And Simulation For D/A Network In R-C Hybrid Sar Adc, Xingyuan Tong, Zhang Yang

Journal of System Simulation

Abstract: D/A conversion network of SAR (SAR: Successive Approximation Register) ADC was discussed. The energy model of the capacitor array in R-C hybrid D/A network was established by using MATLAB. With the combination of resistor string’s static power and capacitor array’s switching power, the power model of the R-C hybrid network in SAR ADC was proposed based on a 65nm CMOS process. Furthermore, by considering matching requirement for the passive components, 12-bit R-C hybrid D/A networks with “5+7”, “6+6” and “7+5” type of structures were simulated and compared. The research can provide significant guidance for circuit design and optimization of …


Research On Double-Sided Linear Induction Motor Of Electromagnetic Catapult Of Carrier-Based Aircraft, Xijun Liu, Kunlun Zhang, Guoqing Liu 2020 Key Laboratory of Magnetic Suspension Technology and Maglev, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China;

Research On Double-Sided Linear Induction Motor Of Electromagnetic Catapult Of Carrier-Based Aircraft, Xijun Liu, Kunlun Zhang, Guoqing Liu

Journal of System Simulation

Abstract: To solve the low efficiency of current steam catapults of carrier-based aircraft, the authors proposed the electromagnetic catapult of carrier-based aircraft using double-sided linear induction motor. The authors analyzed the technical requirements of the catapult of carrier-based aircraft through the kinetic equations, analyzed the drive source of the catapult - long primary double-sided linear induction motor - through the physical model and equivalent circuit, derived the relationship between required thrust and the design parameters of the electromagnetic catapult, and provided specific design parameters. Using computer simulation analysis, the authors analyzed the impact of secondary length, motor pole …


All-Digital Simulation Technique With Application To On-Orbit Spacecraft Maintenance And Servicing, Gaoxiang Ouyang, Li Xin, Dong Xin, Chengmin Sun, Yang Xin 2020 1. Academy of Opto-Electronics, Chinese Academy of Sciences, Beijing 100094, China;;

All-Digital Simulation Technique With Application To On-Orbit Spacecraft Maintenance And Servicing, Gaoxiang Ouyang, Li Xin, Dong Xin, Chengmin Sun, Yang Xin

Journal of System Simulation

Abstract: Aiming at the demand for the on-orbit maintenance, a new simulation technique was developed. The simulation contained on-orbit failures reproduction and location, onboard software upgrade and patch. A virtual technology was used to construct all virtual hardware environment, imitate their function and simulate the real satellite control system. This all-digital platform implemented precise multi-type faults injection, internal state monitoring and data stream intervention very well. So it could roundly simulate and test the software upgrade of the attitude and orbit control systems. It could also be used in the high-fidelity simulation of satellite-ground synchronous operation and maintenance, especially it …


Effect Of Assembly Force On Gas Diffusion Layer For Proton Exchange Membrane Fuel Cell, Yibo Zhou, Jianjian Wang 2020 1. China Automotive Technology & Research Center, Tianjin 300072, China;;2. State Key Laboratory of Engines, Tianjin University, Tianjin 300072, China;

Effect Of Assembly Force On Gas Diffusion Layer For Proton Exchange Membrane Fuel Cell, Yibo Zhou, Jianjian Wang

Journal of System Simulation

Abstract: A three-dimensional multi-flow channel proton exchange membrane fuel cell (PEMFC) model has been developed to investigate the deformation of gas diffusion layer (GDL) with different assembly force and different contact ratio of channel. The results indicate that the GDL under the land part changes significantly while the central region under the flow channel almost has no deformation with increasing assembly force. When the contact ratio of channel is not 100%, the deformation of GDL is not symmetrical due to the shear stress, and the thickness of GDL under the flow channel even exceeds its initial thickness, which produces the …


Respond Performance To Dynamic Heat Resource Of Organic Rankine Cycle For Waste Heat Recovery On Vehicle, Zhao Li, Huang Wei 2020 Key Laboratory of Efficient Utilization of Low and Medium Grade Energy, Tianjin University, MOE, Tianjin 300072, China;

Respond Performance To Dynamic Heat Resource Of Organic Rankine Cycle For Waste Heat Recovery On Vehicle, Zhao Li, Huang Wei

Journal of System Simulation

Abstract: Complex traffic leads to a dynamic behavior of exhaust gas of vehicle. Therefore, a real operating of Organic Rankine Cycle (ORC), which is used for heat recovery, deviates the design working condition at most of time with a low operating efficiency. To solve the problem, a dynamic model of ORC system verified by experiment result was built. The dynamic behavior of the heat resource, divided into 6 modes, was used as an input of external condition to the developed model. The impact results of the step mass flow rate and the temperature of heat resource to the stability of …


Fault Modeling And Simulation Of Swing Infrared Earth Sensor, Jiansong Chang, Xinyan Liu 2020 1. Beijing Institute of Control Engineering, Beijing 100190, China;;2. Science and Technology on Space Intelligent Control Laboratory, Beijing 100190, China;

Fault Modeling And Simulation Of Swing Infrared Earth Sensor, Jiansong Chang, Xinyan Liu

Journal of System Simulation

Abstract: In order to meet the requirements of refined modeling and fault simulation, function modules of swing infrared earth sensor (IRES) was identified according to its working principle, main fault modes of each module was analyzed, mathematical fault model based on physical mechanism was designed, and a program for normal and fault simulation was written. The refined fault model can calculate attitude angles exactly, reflect signal relationship between inside modules, and simulate various fault modes effectively. The model can be used in simulating, testing and fault diagnosis and so on.


Computed Terahertz Wave Propagation In Marine Protective Coating, Wanli Tu, Shuncong Zhong, Zhou Qing, Ligang Yao 2020 1. School of Mechanical Engineering and Automation, Fuzhou University, Fuzhou 350108, China;;2. Marine Engineering Institute, Jimei University, Xiamen 361021, China;;3. Fujian University Engineering R&D Centre for Design and Manufacturing of Marine Engineering Equipment, Fuzhou 350108, China;;

Computed Terahertz Wave Propagation In Marine Protective Coating, Wanli Tu, Shuncong Zhong, Zhou Qing, Ligang Yao

Journal of System Simulation

Abstract: The propagation of terahertz radiation in marine protective coatings was investigated based on Finite-difference time-domain method. The theoretical framework using terahertz waves for the detection of marine protective coatings was established; also, both intact and defected coating system were modelled and analyzed. The reflected radiation properties were recorded for quantitative characterisation of marine protective coating thickness. Furthermore, diagnostic analysis was done for the defects of the coating system, such as bubbling and oxidation of rust. The Finite-difference time-domain model provides some theoretical basis for nondestructive testing and evaluation of marine protective coating system by terahertz pulsed imaging technology …


Research On Effect Of Harmonic Source Equivalent Model On Harmonic Power Flow, Zhenguo Shao, Wenbo Su, Zhaoxiang Li 2020 Fuzhou University, Fuzhou 350116, China;

Research On Effect Of Harmonic Source Equivalent Model On Harmonic Power Flow, Zhenguo Shao, Wenbo Su, Zhaoxiang Li

Journal of System Simulation

Abstract: The models and parameters of harmonic source are the main factors that affect the calculation accuracy of harmonic flow. Harmonic source was divided into linear load and non-linear load and then modelled separately. The algorithm flowcharts, coupling method, decouple method and linear method, were analyzed with power source model, current source model and current source-impedance model correspondingly. The frequency response of those models was compared with a simple example. It indicates that the model of linear load and its affect in harmonic frequency are the key factors influencing computational accuracy of harmonic power flow. Then an example of harmonic …


Research Of 3d Cloud Illumination Model Based On Importance Sampling, Yonghua Xie, Fuxing Yuan, Wang Chang 2020 1. School of Computer and Software, Nanjing University of Information science and Technology, Nanjing 210044, China;;2. Jiangsu Engineering Center of Network Monitoring, Nanjing University of Information and Technology, Nanjing 210044, China;

Research Of 3d Cloud Illumination Model Based On Importance Sampling, Yonghua Xie, Fuxing Yuan, Wang Chang

Journal of System Simulation

Abstract: Currently existing 3D cloud simulation illumination models were confronted with the shortcomings such as complexity of implementation and low rendering efficiency. Herein a calculation method for illumination model based on importance sampling was proposed; Aiming at the problems of the old phase function, a new phase function was proposed to improve the rendering efficiency and quality. By the design of the importance function, the method did importance sampling in integrated interval and combined two phase functions to render the cloud. The results of the simulation show that the presented method has enhanced the rendering speed with the guarantee of …


Feature Model Visualized Configuration Method Of Digital Museum, Caixia Li, Song Yuan, Zhaoyang Feng, Wang Yi, Li Zhi 2020 1. Satellite Marine Tracking and Control Departement of China, Jiangyin 214431, China;;

Feature Model Visualized Configuration Method Of Digital Museum, Caixia Li, Song Yuan, Zhaoyang Feng, Wang Yi, Li Zhi

Journal of System Simulation

Abstract: It is an issue to be solved urgently transforming Digital Museum simulation resource description from natural language into visual simulation in order to reuse and share the resource expeditiously. During the analysis for feature model technique and Internet of Data (IOD), a method for feature model visualized configuration of digital museum based on IOD is proposed. The approach achieves the visualized configuration for simulation resource from domain feature model to application feature model which includes definition of feature model, description with feature data semantic tag and association semantic tag, visualized configuration with feature editor, feature association editor and …


Design And Application Of Underwater Unmanned Vehicle Simulation System For Navigation And Obstacle Avoidance, Zheng Wei, Qiming Zou, Wenxi Ni 2020 The 705th Research Institute, China Shipbuilding Industry Corporation, CSIC, Xi′an 710075, China;

Design And Application Of Underwater Unmanned Vehicle Simulation System For Navigation And Obstacle Avoidance, Zheng Wei, Qiming Zou, Wenxi Ni

Journal of System Simulation

Abstract: Accurate navigation and location, effective detection and realtime obstacle avoidance are the bases of Underwater Unmanned Vehicle (UUV) for long voyage mission accomplishment. To achieve intellectual demonstration and validation functions of UUV, which was studied on the base of integrated navigation model and dynamic obstacle-avoidance strategy on detection, the systems analysis aimed to simulated object characteristics was accomplished. Besides, models-component encapsulation method together with concurrent multi-thread simulation skeleton on discrete events was derived, followed by designed UUV navigation and obstacle-avoidance simulation system, compartmentalized function modules and marked-out simulation flow. The simulation application of UUV was achieved to …


Evaluation Of Anti-Multipath Performance To Satellite Navigation Signal Tracking On L1/E1/B1 Frequency Band, Mao Hu, Dewei Wu 2020 School of Information and Navigation, Air Force engineering University, Xi'an 710077, China;

Evaluation Of Anti-Multipath Performance To Satellite Navigation Signal Tracking On L1/E1/B1 Frequency Band, Mao Hu, Dewei Wu

Journal of System Simulation

Abstract: Aiming at analysis requirement to anti-multipath performance of satellite navigation signal system, on the basis of expounding modulation types of latest navigation signal system on L1/E1/B1(1575.42MHz) frequency band, the analytical expressions of code tracking multipath error envelope and carrier phase multipath error based non-coherent early minus late process discriminator and arctangent discriminator was deduced respectively, the effect of receiver correlation distance, receiver front-end bandwidth and navigation signal modulation types to multipath error were analyzed through simulation. The results show that B1-C open service signal of BDS should adopt MBOC(6,1,1/11) modulation of similarly Galileo E1OS combination mode, and B1 …


Simulation Contrast Analysis On Rigid And Flexible Movements Of Multi-Fins Coordinated Propulsion Mode, Xie Ou, Boquan Li, Yan Qin 2020 1. School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013, China;;2. School of Mechanical Engineering, Suzhou University of Science and Technology, Suzhou 215009, China;

Simulation Contrast Analysis On Rigid And Flexible Movements Of Multi-Fins Coordinated Propulsion Mode, Xie Ou, Boquan Li, Yan Qin

Journal of System Simulation

Abstract: A novel type of bionic underwater hybrid propulsion mode was proposed. By the means of the coordination control of the multi-fins, a propulsion mode combines the undulation propulsion of fish and the jet propulsion of jellyfish was developed, and was capable of achieving a serial of motions: undulating, jetting, turning, submerging, emerging and braking. The rigid and flexible water stabilizer kinematics model was established and the numerical simulation was performed for undulation and jet propulsion mode of the rigid and flexible water stabilizer by using a CFD method. The simulation results show that the dynamic characteristics and swimming performance …


Identification Of Wiener Model Based On Improved Differential Evolution (Sade) Algorithm, Xiaoping Xu, Bai Bo, Fucai Qian 2020 1. School of sciences, Xi'an University of Technology, Xi'an 710054;;

Identification Of Wiener Model Based On Improved Differential Evolution (Sade) Algorithm, Xiaoping Xu, Bai Bo, Fucai Qian

Journal of System Simulation

Abstract: To identify the parameters of nonlinear Wiener model, a new identification method was put forward based on a SADE algorithm. Its basic idea is as follows: the Sigmoid function and adaptive mutation operator were adopted to improve the mutation operation part of the basic differential evolution algorithm, accordingly, the disadvantages of the basic differential evolution algorithm, such as premature convergence, instability, etc, were effectively overcome. The proposed algorithm was used to parameter identification problem of Wiener model; moreover, the accuracy of identification was well improved. In the numerical simulation, compared with other relevant existing algorithms, simulation results show that …


Image Denoising Algorithm Based On Method Noise Sparse Representation Dictionary Learning, Lishao Huang, Haiying Wen, Sisi Gu 2020 College of Electronics and Information Engineering, Hunan University of Science and Engineering, Yongzhou 425199, China;

Image Denoising Algorithm Based On Method Noise Sparse Representation Dictionary Learning, Lishao Huang, Haiying Wen, Sisi Gu

Journal of System Simulation

Abstract: For the shortcoming of losting partial texture information with image denoising process, the image denoising algorithm based on method noise sparse representation was proposed. The method noise, which was defined as the difference between the noisy and the denoised image, was obtained by guided filter. Then redundant dictionary was learned by improved dictionary learning method and the method noise. The image texture information in method noise was extracted by the learning dictionary, and image was restored by the extracted image texture information and denoised image by guided filter. The experimental results demonstrate that the peak signal to noise ratio …


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