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Full-Text Articles in Physical Sciences and Mathematics

Behavioral Simulation Modeling Of Single Photon Avalanche Diode, Xu Yue, Xiaopeng Xie, Yue Heng Jan 2021

Behavioral Simulation Modeling Of Single Photon Avalanche Diode, Xu Yue, Xiaopeng Xie, Yue Heng

Journal of System Simulation

Abstract: An accurate behavioral simulation model for single photon avalanche photodiode (SPAD) was proposed. This presented model solved the convergence problem existed in SPAD avalanche current simulation, and achieved the basic static DC and dynamic AC behaviors modeling. The model functions were extended. Two important statistical effects of dark-counting and after-pulsing phenomena were included in this model according to their physical mechanisms. The model has been written in Verilog-A hardware description language, showing good characteristics of transplantation and universality. A good agreement with more than 90% accuracy is achieved between the model basic simulations and the experimental results, proving the …


Decoupling And Partial Iterative Calculation Method Of Flexibility Dynamics, Xianzhong Wang, Minlan Tang, Jinfang Dong Jan 2021

Decoupling And Partial Iterative Calculation Method Of Flexibility Dynamics, Xianzhong Wang, Minlan Tang, Jinfang Dong

Journal of System Simulation

Abstract: Some spacecrafts have large solar panels and a lot of propellant. These spacecrafts with flexible modes can reach hundreds of order. High-powered computers are needed for these spacecrafts,flexibility dynamics iterative operation within several milliseconds. The measures of decoupling flexibility vibration from body rotation and partial iterative calculation were applied to avoid no convergence of the flexibility dynamics iterative operation because of iterative computing error. The parameters of flexible dynamics model which were decoupled could be calculated off-line. The amount of calculation was decreased for the decoupled flexibility dynamics model as parameters could be computed before simulation. The method doesn't …


Construction Of Real-Time Simulation Model Of Fire Fighting Pump System Of Airport Fire Engine, Lishan Jia, Liwen Wang Jan 2021

Construction Of Real-Time Simulation Model Of Fire Fighting Pump System Of Airport Fire Engine, Lishan Jia, Liwen Wang

Journal of System Simulation

Abstract: To the simulation of fire fighting pump system of airport fire truck in driving training simulator of airport fire engine, the method of construction of simulation model of fire fighting system was promoted. Simulation model of centrifugal pump of airport fire truck was constructed, which was designed for simplification to satisfy the real-time performance of running of system. Considering fire fighting operation of fire truck, simulation model of operation of fire fighting pump system was constructed, which could not only simulate common fire fighting operation of fire truck, but also simulate running status of low pressure of fire fighting …


Modeling And Simulation Of Detection Probability For Whole Airspace Oriented Optical Target, Hongie Dang, Haozhang Yu, Luofeng Deng, Guanlei Jiang Jan 2021

Modeling And Simulation Of Detection Probability For Whole Airspace Oriented Optical Target, Hongie Dang, Haozhang Yu, Luofeng Deng, Guanlei Jiang

Journal of System Simulation

Abstract: To ensure the target within view field is the precondition of the tracking measuring equipment working normally, which is described by probability in engineering. A precise method of optical equipment detection probability was addressed aiming at the maneuverable targets, an exact description method of the whole airspace detection according to optical sensor was put forward, and a detection probability model for optical target was set up. A calculation method suited the model was confirmed,which was given by simulation analysis of the algorithm's calculation performance, the influence of model various parameters on algorithm was analyzed, and a comparison was given …


Research On Safety Protection Compositive Simulation Test Bed For Electric Secondary System, Zheniu Zhou, Angang Zheng, Heping Zou Jan 2021

Research On Safety Protection Compositive Simulation Test Bed For Electric Secondary System, Zheniu Zhou, Angang Zheng, Heping Zou

Journal of System Simulation

Abstract: Existing information and network security simulation methodologies of model construction were analyzed and compared with each other, and applicability and limitations of each of them were summarized. Then according to safety protection needs to electric secondary system, based on previous research results of security simulation aiming at individual and partial objects, a safety protection compositive simulation test bed was designed and implemented in which eight kinds of simulation technology and solutions were integrated. This test bed included four simulation layers and seventeen categories of simulation test, and achieved a large scale, distributed, linkage-type simulation for comprehensive information security. This …


Rendezvous And Docking Digital Simulation System Based On Matlab, An Hao, Zhenshen Qu, Changhong Wang Jan 2021

Rendezvous And Docking Digital Simulation System Based On Matlab, An Hao, Zhenshen Qu, Changhong Wang

Journal of System Simulation

Abstract: On the background of lunar orbit rendezvous and docking (RVD), a framework of the simulation system was designed. The dynamics, navigation and controller of the RVD system were built in detail, and a Simulink model of the lunar orbit RVD was established based on these results. A user interface and a 3D dynamic demonstration were designed to make the operation convenient and intuitive.The digital simulation system can be used to verify the lunar orbit RVD missions incipiently. Furthermore,a semi-physical RVD simulation was taken by using the modified model. The simulation results show the effectiveness of the inertia-visual integrated navigation …


Study On Key Nodes Analysis Method Of Space Information Network, Mingzhi Zhang, Luo Kai, Wu Xi Jan 2021

Study On Key Nodes Analysis Method Of Space Information Network, Mingzhi Zhang, Luo Kai, Wu Xi

Journal of System Simulation

Abstract: Because of the dynamic of the Space Information Network (SIN), the key nodes analysis should be considered in a time section. The method of the key nodes analysis of SIN was introduced based on time slice. On this basis, combining with the features of satellite, a new method of the key nodes analysis of SIN based on accumulation pattern was proposed. The new method used the weighted processing technology to the access time and the access number, and then transformed the SIN to a static weighted network. Through the simulation using STK and MATLAB, the results of experiments show …


Interference Alignment Based Throughput Optimization Model Of Multi-Hop Networks, Zui Xiong, Keren Wang, Jin Hu, Feng Hui Jan 2021

Interference Alignment Based Throughput Optimization Model Of Multi-Hop Networks, Zui Xiong, Keren Wang, Jin Hu, Feng Hui

Journal of System Simulation

Abstract: Due to its benefits of enbancing the spectrum utility in information theory, interference alignment (IA) is quickly adopted in multi-hop wireless networks. The constraints of "node activity in the existing throughput optimization model with IA are insufficient for converging to the optimal solution; the feasibility of IA is not involved. Thus, some measures were taken to compensate for the problems above.The longitudinal constraints of node activity were presented, and the feasibility condition of IA was discussed by the means of setting constraints on the data rates and the macimal number of interfering links at each node. The simulation results …


Co-Simulation Of Intelligent Lower Limb Assist Device Virtual Prototype, Zhenze Liu, Fengming Wang, Xuange Zhang, Cangqiong Yin Jan 2021

Co-Simulation Of Intelligent Lower Limb Assist Device Virtual Prototype, Zhenze Liu, Fengming Wang, Xuange Zhang, Cangqiong Yin

Journal of System Simulation

Abstract: A virtual prototype model of power assist device for lower extremity was established to improve the efficiency and reliability of the power assist device design. The mechanical model using software CATIA was introduced to ADAMS to establish the virtual model, so as to carry out the kinematics and dynamics simulations, and combined the previous model established by ADAMS with the control model established in MATLAB/Simulink to realize the co simulation of the system. According to the characteristics of human gait data, PID control algorithm was used to control lower limb power system. The simulation results demonstrate that the control …


Local Deformation Method For Soft Cylindrical Model, Hongqian Chen, Fang Yi, Qianyu Yang, Fengxia Li, Chen Yi Jan 2021

Local Deformation Method For Soft Cylindrical Model, Hongqian Chen, Fang Yi, Qianyu Yang, Fengxia Li, Chen Yi

Journal of System Simulation

Abstract: To simulate the bending effect for the soft cylindrical objects in realtime, a deformation method was proposed that could achieve the detiail-preservation and surface area-preservation. The method obtained the shape properties such as the bottom and the height from the original cylindrical model. The base model consisted of the regular mesh was built according to the shape properties. The detail model could be obtained by the raidus function of separating from the base model. The uniform deformation algorithm for the base model was adopted to decrease the complexity of the processing. The damping oscillation curve was employed t0 simulate …


Simulation Method For Large-Scale Water Area In Rainy Days, Tingting Yao, Zhongming Xie, Yunfei Li Jan 2021

Simulation Method For Large-Scale Water Area In Rainy Days, Tingting Yao, Zhongming Xie, Yunfei Li

Journal of System Simulation

Abstract: The rendering of large-scale water area rain scene is one of the most challenging problems in computer graphics, and a method of rendering large-scale water area rain scene was proposed. By introducing the improved wave equation into the fuctuation of water surface and the interaction of water and raindrop, and incorporating the periodicity and wind tendency of FFT, an interactive fluctuation of water mathematical model in rainy days was established, based on which an interactive height map was rendered. Through the lighting rendering, the reflection effect and rain streaks were simulated. In order to enhance the efficiency, the level-of- …


Study On 3d Battlefield Construction Based On Uav Remote Sensing Images, Bin Liu, Xiangning Chen, Lianpeng Guo Jan 2021

Study On 3d Battlefield Construction Based On Uav Remote Sensing Images, Bin Liu, Xiangning Chen, Lianpeng Guo

Journal of System Simulation

Abstract: According to the demand for rapid construction of 3D battlefield environment, an automatic 3D battlefield environment construction technology was proposed based on UAV Remote Sensing Images. The specified area remote sensing images were captured using UAV The sparse reconstruction and calibrations were obtained using SFM method. The dense reconstruction was done using multi-view stereo matching algorithms. The scene surface was fit using dense points and texture mapping was done to generate 3D battlefield environment. The experimental results show that the proposed method can quickly reconstruct the battlefield, and improves the efficiency of 3D modeling. It has significant intelligence in …


Real-Time Shadow Algorithm Improvements In Digital Earth Scenarios, Defa Zhang, Yiwei Wang, Wang Rui Jan 2021

Real-Time Shadow Algorithm Improvements In Digital Earth Scenarios, Defa Zhang, Yiwei Wang, Wang Rui

Journal of System Simulation

Abstract: Studying real- time shadow generating and rendering algorithms in digital earth virtual reality scenes, a new method was provided to improve the shadow rendering quality and efficiency of earth scenes, based on the characteristics of huge dataset, huge coordinates and frequent scheduling mechanisms. Comparing with the classics CSM shadow map algorithm, the method proposed focused on the optimization of shadow splitting ranges, as well as a new pipeline separating the rendering steps of terrain tiles and objects, so to improve both the correctness and efficiency. analyzes The problems caused by shadow rendering while running dynamic terrain tile scheduler simultaneously …


Research Of Liver Solid Texture Synthesis And Mapping Method With Cuda Acceleration, Guodong Chen, Hanxin He Jan 2021

Research Of Liver Solid Texture Synthesis And Mapping Method With Cuda Acceleration, Guodong Chen, Hanxin He

Journal of System Simulation

Abstract: A liver solid texture synthesis and mapping method based on Computer Unified Device Architecture acceleration (CUDA) was proposed to solve the problem of the overlong time consuming within the period of synthesizing liver solid texture in traditional way. The relevance in traditional serial texture synthesis was elim inated in the new method. The work of selecting and distributing blocks of space synthesis of the liver solid texture was processed by using the parallel processing of multiple threads based on CUDA. Both the procedures of tinting the surface grid nodes of liver model and internal point set traversal in mapping …


Mobile Robot Slam Simulation With Multi Measurement Update, Yafang Xu, Zuoleit Sun, Liansun Zeng, Zhang Bo Jan 2021

Mobile Robot Slam Simulation With Multi Measurement Update, Yafang Xu, Zuoleit Sun, Liansun Zeng, Zhang Bo

Journal of System Simulation

Abstract: Aiming at the problem of the accumulation of linearization error in the nonlinear system linearizing of Simultaneous Localization and Mapping (SLAM) in mobile robot, an algorithm named multi measurement update was put forward according to the analysis of Fisher information. In order to compute the state estimation after each measurement update, the Fisher information weight relationship between prediction variable and update variable was made use of Due to a number of data association with an estimation which was more close to the real data than the former, the algorithm could achieve a more accuracy posterior state. As a result, …


Indoor Positioning System Algorithm Based On Rfid, Xuejun Shi, Zhicheng Ji Jan 2021

Indoor Positioning System Algorithm Based On Rfid, Xuejun Shi, Zhicheng Ji

Journal of System Simulation

Abstract: In order to solve the radio frequency identification (RFID) positioning problem, the working principle, advantages and disadvantages of two positioning methods (AOA and TDOA) were analyzed in detail by comparison, on the basis of which, an indoor positioning hybrid approach of Ultra High Frequency (UHF) RFID was proposed. This proposed approach took the AOA as the core and integrated the idea of time diference in TDOA. Moreover; the stepping motor and UHF reader were used simultaneously instead of antennas array to make UHF RFID reader whirl around an axis. Therefore, it is easy to scan each tag that can …


Application-Aware Cross-Layer Enrgy-Eficient Routing Scheme, Xu Fang, Hiyin Zhang, Wang Jing, Xu Ning, Zhijong Wang, Deng Min Jan 2021

Application-Aware Cross-Layer Enrgy-Eficient Routing Scheme, Xu Fang, Hiyin Zhang, Wang Jing, Xu Ning, Zhijong Wang, Deng Min

Journal of System Simulation

Abstract: An aplication- aware cross-layer energy-effcient routing scheme (ACER) was presented to minimize the effect of supplt of terminals in ad hoc network composed of smart mobile devices. Features of energy consumption were sensed by application aware energy model with the application monitor and the remaining energy monitor. Stability of network path was monitored by link stability monitoring module in Data link layer. As the scheme used the idea of cross-layer design, network topology information, application-aware information in application layer and link-stability were utilized synthetically to make routing deisions in network layer;Simulations were crried out on NS2 platform. The …


Trnek Befor Detet Agoritmn For Weak Iret Based On Ergodic Hogh Tasform, Yunfei Guo, Xiaofeng Zheng, Dongliang Peng, Zebin Zeng Jan 2021

Trnek Befor Detet Agoritmn For Weak Iret Based On Ergodic Hogh Tasform, Yunfei Guo, Xiaofeng Zheng, Dongliang Peng, Zebin Zeng

Journal of System Simulation

Abstract: The performance of track-before-detect (TBD) algorithm based on standard Hough Transform is not satisfied due to low detection probability and long elapsed time. For this problem, an Ergodic Hough Transform based TBD method was proposed. The raw radar echo whose amplitude exceeded the first threshold was stored separately and stacked into a data space; all diferent data were combined to calculate line parameter which then was mapped into a parameter space and the amplitude of each paired wae added to an accumulator. All cells whose amplitude exceeded the second threshold was used to estimate the last line parameter and …


Test Data Compression Based On Logical Operationand Dimidiate Partition, Wu Qiong, Huang Li Jan 2021

Test Data Compression Based On Logical Operationand Dimidiate Partition, Wu Qiong, Huang Li

Journal of System Simulation

Abstract: A new test data compression based on logical operation and dimidiate partition was proposed. The whole test was partitioned to several length-fixed blocks. Then logical operation was applied into runs of Is or 0s or alternating bits. They were turned into all 0s. For the others, dimidiate partition technique was used until they got to the minimum length. The length of code words could be expressed by the times of dimidiate and it is easy to coding when they are turned into all 0s. Compared with traditional data-coding methods the depression structure is simple and reduced the costs of …


Study Of Improved Generalized Predictive Control In Ball Mill Application, Lingfang Sun, Jingmiao Sun Jan 2021

Study Of Improved Generalized Predictive Control In Ball Mill Application, Lingfang Sun, Jingmiao Sun

Journal of System Simulation

Abstract: Direct-fired pulverizing system with double inlets and outlets is regarded as important generating equipment in power plant, which has characteristics of nonlinear, multivariable, strong coupling and time-varying. Started from the mechanism of law, the mechanism mathematical model of the ball mill was established and a certain amount of disturbance transfer ftinction model was added in a mathematical model of the mechanism of input variables to give step disturbance tests to establish the ball mill system. Combining the most widely used basic control--PID control as industrial process control, and on the basis of general generalized predictive control algorithm, the generalized …


New Identify Based Proxy Signature Scheme, Xiaojing Hong, Bin Wang Jan 2021

New Identify Based Proxy Signature Scheme, Xiaojing Hong, Bin Wang

Journal of System Simulation

Abstract: Proxy signature schemes allow a proxy signer to generate proxy signatures on behalf of an original signer. Mambo, et ah first introduced the notion of proxy signature and a lot of research work can be found on this topic nowadays. To simplify key management, many identity based proxy signature schemes were proposed. However, some existing schemes are vulnerable to proxy key exposure attack. It is necessary to propose a security model for identity based proxy signature schemes against proxy key exposure attack. Then an efficient scheme based on pairings was presented, which is provably secure in the random oracle …


Efficient Real-Time Traffic Signal Control Algorithm, Zhongcheng Yang, Ye Chen, Zhenyu Yang Jan 2021

Efficient Real-Time Traffic Signal Control Algorithm, Zhongcheng Yang, Ye Chen, Zhenyu Yang

Journal of System Simulation

Abstract: For real time taffic signal contol isus, a mathematical model was proposed to minimize the waiting ime, meanwhile a huristi search aigorihm was given to sove the optinal sluton Simulatin Tresuts show that the hcurisi scarceh algorim sufrfs fom being couataoalal complx and umstable, therefore, a multi sage decisin optimization algorihm is added, and the serehes adopt in all stages subject to a time limit, which ensures a stable and real-time algorithm, and also a soution in fixed time. Simulation resuts based on actal tafic data show that the waiting time can be reduced in comparison with that of …


Modeling Emergence Of Network Radar Countermeasure System, Huang Chen, Jianqing Qi, Fangzheng Liu Jan 2021

Modeling Emergence Of Network Radar Countermeasure System, Huang Chen, Jianqing Qi, Fangzheng Liu

Journal of System Simulation

Abstract: Network radar countermeasure system (NRCS) is a new kind of integrated electronic warfare system with the integrated network developing trend of radar and EW equipment, and emergence is the typical complex feature of NRCS. The connotation and composition of the NRCS emergence was interpreted. Four sources of the NRCS emergence were analyzed: composition effect, structural effect, interaction effect and environmental effect. The conceptual models and mathematical models of the NRCS emergence were built from three aspects: system reconnaissance detection emergence, system target identification emergence and system jamming emergence. Simulation results coincide with the NRCS emergence source analysis, which verifies …


Simulation Of Energy Optimization For Cooling Coil In Central Air-Conditioning System, Qinglong Meng, Xiuying Yan Jan 2021

Simulation Of Energy Optimization For Cooling Coil In Central Air-Conditioning System, Qinglong Meng, Xiuying Yan

Journal of System Simulation

Abstract: The optimized control of minimizing energy consumption in one air-conditioning system was studied. The main models that needed in the simulation software HVACSIM+ for air handling unit were introduced. The AHU and rooms of the first floor of certain Building were taken as the simulation target. Then the function describing the relation between the consumption of cooling coil and the chilled water velocity was found and taken as the objective function. With improved cyclic variable method, the controller^ parameters were optimized. Results show that the simulation system runs steadily while the controller works with the optimal parameters, and the …


Gait Simulation Of Snake Robot Based On Cpg Method, Gao Qin, Zhelong Wang, Weijian Hu, Lanying Zhao Jan 2021

Gait Simulation Of Snake Robot Based On Cpg Method, Gao Qin, Zhelong Wang, Weijian Hu, Lanying Zhao

Journal of System Simulation

Abstract: Biological snakes in nature have a variety of periodic motion patterns such as serpentine motion, linear motion and lateral motion. Gaits diversity has greatly improved the adaptability of natural snakes to complex environment. Biologists has proved that such rhythmic movements of vertebrate animals are generated by CPG (the central neural pattern generator). Special mechanical structure of a snake robot with high degree offreedom and locomotion characteristics of different gaits was considered to bulid a suitale CPG network model. Hopf oscillators were chosen as neuron models of a central pattern generator owing to their stable features. A snake robot prototype …


Optimized Analysis Of Milling Thin-Wall Parts Based On Shell Element Models, Yusong Liao, Han Jiang Jan 2021

Optimized Analysis Of Milling Thin-Wall Parts Based On Shell Element Models, Yusong Liao, Han Jiang

Journal of System Simulation

Abstract: As to milling the thin-wall part accurately, here with the finite element model composed of SHELL elements, the effects of lowering position, size of the part and cutting parameters to the deformations of the thin-wall part were analyzed and compared, and the corresponding theoretical analysis was provided. The conclusions can be got as; the model composed of SHELL elements can analyze the factors causing the deforroations of the thin-wall part and optimize the cutting method and cutting parameters effectively to improve the machining accuracy and efficiency.


Modeling And Simulation Of Traction System In Hybrid Shunting Locomotive, Kun Shen, Wang Ling, Wang Jian, Xiaoyang Yao Jan 2021

Modeling And Simulation Of Traction System In Hybrid Shunting Locomotive, Kun Shen, Wang Ling, Wang Jian, Xiaoyang Yao

Journal of System Simulation

Abstract: The structure of traction system in hybrid shunting locomotive was analyzed, and the working principles of traction system under multiform power models were introduced. Based on which, the models of traction system and power accumulators of this hybrid shunting locomotive were built by MATLAB/Simulink, then the simulation experiments on hybrid shunting locomotive with the power models of hybrid power, and pure diesel generator power or pure accumulator power were done respectively. The simulation results show that hybrid shunting locomotive can achieve reliable operation in diflFerent conditions by the designed main circuit structure, parameters and system energy management strategy.


Impact Of Number Of Solar Cells In Parallel/Series And Temperature On Junction Capacitance, Zhigang Zhao, Chunjie Zhang, Gao Pu, Hutang Sang, Xiaoqian Li Jan 2021

Impact Of Number Of Solar Cells In Parallel/Series And Temperature On Junction Capacitance, Zhigang Zhao, Chunjie Zhang, Gao Pu, Hutang Sang, Xiaoqian Li

Journal of System Simulation

Abstract: The study to the dynamic parameters of the photovoltaic cell is of crucial importance for the design of the corresponding afterward stage controller in the photovoltaic power generation system. Beginning with the analysis to physical mechanism of the photovoltaic cell, more accurate equivalent formulation of the junction voltage and bias voltage of the photovoltaic cells /module/array was deduced, and the explicit formulation between the bias voltage and output voltage was received by using the Lambert W function based on equivalent series resistance and the saturation current. The formulation was adopted which combined the engineering mathematics model and intrinsic carrier …


Evaluation And Analysis Of New Method Of Measurement Of Target Scattering Matrix, Zhenyu Huang, Zhao Bo, Huanyao Dai, Liandong Wang, Xuequan Zhou Jan 2021

Evaluation And Analysis Of New Method Of Measurement Of Target Scattering Matrix, Zhenyu Huang, Zhao Bo, Huanyao Dai, Liandong Wang, Xuequan Zhou

Journal of System Simulation

Abstract: The basic theory of radar polarization signal processing is measurement of the target scattering matrix. The current algorithm of measurement of the target scattering matrix is gotten through orthogonal dual polarization channel in time-sharing or simultaneously, which demands orthogonal polarization measurement signals with complex coding. The measuring accuracy is higher. The complexity and the cost of the system are relatively higher. Scattering matrix can also be obtained by making use of the spatial polarization characteristics of the antenna to processing the radar echo without structure reformation of the radar. It only. needs to renewal measurement technology. The comparison and …


Non-Cooperative Target Feature Point Cloud Registration Optimization Based On Icp Algorithm, Wei Liang, Muyao Xue, Huo Ju, Jinjie Zhang Dec 2020

Non-Cooperative Target Feature Point Cloud Registration Optimization Based On Icp Algorithm, Wei Liang, Muyao Xue, Huo Ju, Jinjie Zhang

Journal of System Simulation

Abstract: Aiming at the pose measurement caused by non-cooperative targets in visual measurement that cannot provide cooperation information,the ICP(Iterative Closest Point) algorithm is used to register the point cloud down-sampling data acquired at different times to complete the relative pose measurement of the target.The point cloud data of the target at the current moment is obtained using the structure from motion algorithm and the feature point matching algorithms are compared based on threshold matching and optical flow matching method.The extracted feature points are reconstructed by triangulation.The relative pose changes of the object at different times are calculated by using …