Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 3211 - 3240 of 3363

Full-Text Articles in Physical Sciences and Mathematics

Fault Diagnosis System Of Lithium Battery Based On Petri Net, Diju Gao, Lan Xi, Aidi Shen Jan 2019

Fault Diagnosis System Of Lithium Battery Based On Petri Net, Diju Gao, Lan Xi, Aidi Shen

Journal of System Simulation

Abstract: To improve the efficiency of lithium battery fault diagnosis system, a fault diagnosis system based on Petri net is proposed. The fault diagnosis model based on Petri net came from the analysis of the inconsistent voltages between single cell in lithium batteries during charge and discharge. The system can find the fault causes according to abnormal signals detected by sensor. The control logic diagram of the fault diagnosis model is established by state flow, and simulated by simulink. The results of model verification and simulation show that the cause for inconsistent voltage is distinguished meticulously by the fault diagnosis …


From Situation Cognition Stepped Into Situation Intelligent Cognition, Zhu Feng, Xiaofeng Hu, Wu Lin, Xiaoyuan He, Xuezhi Lü, Liao Ying Jan 2019

From Situation Cognition Stepped Into Situation Intelligent Cognition, Zhu Feng, Xiaofeng Hu, Wu Lin, Xiaoyuan He, Xuezhi Lü, Liao Ying

Journal of System Simulation

Abstract: Aimed at operational situation cognition and some relevant problems under the background of the Joint-Tactical, some deep researches are carried out in this paper. The concept models of combat situation cognition and situation intelligent cognition are proposed respectively, and some related concepts are clarified. The situation intelligent cognition technology framework is proposed, and five key problems which should be solved are analyzed, and the possible technical routes are given. These research contents and achievements build a foundation for stepping into the situation intelligent cognition from combat situation cognition.


Achievements And Developments Of Hysteresis And Creep Of Pneumatic Artificial Muscles, Shenglong Xie, Haitao Liu, Jiangping Mei Jan 2019

Achievements And Developments Of Hysteresis And Creep Of Pneumatic Artificial Muscles, Shenglong Xie, Haitao Liu, Jiangping Mei

Journal of System Simulation

Abstract: Regarding to the problems of hysteresis and creep, the developments and achievements of the research on pneumatic artificial muscles at home and abroad are systemically reviewed. The state of the art is summarized in terms of characteristics, reasons causing, modeling and control strategies based on the hysteresis and creep modeling. The problems in recent research are analyzed and the direction for further research is put forward. The theoretical study on hysteresis and creep of pneumatic artificial muscle is limited. The hysteresis modeling needs to consider the time-varied parameters caused by creep. Neural network modeling needs to solve …


Mathematical Modeling And Simulation Of Hydraulic Governor For Marine Diesel Engine, Chen Jian Jan 2019

Mathematical Modeling And Simulation Of Hydraulic Governor For Marine Diesel Engine, Chen Jian

Journal of System Simulation

Abstract: The speed control and load limit of marine diesel engine are implemented by hydraulic governor, of which the characteristics directly determines the performance of generator set. Therefore, it is an important content of marine engine room simulator training to strengthen the students’ training and understanding of the working characteristics of the hydraulic governor. In the existing marine engine room simulators, the simulation model of hydraulic governor is too simple to carry out further training tasks. According to the working principle of hydraulic governor and the training purpose of marine engine room simulator, the mathematical model of UG-8 hydraulic governor …


Research And Simulation For Military Contests Based On Ahp And Entropy Models, Rusheng Ju, Zhengqiu Zhu, Yunxiu Zeng, Ruixian Wang, Xiaogang Qiu Jan 2019

Research And Simulation For Military Contests Based On Ahp And Entropy Models, Rusheng Ju, Zhengqiu Zhu, Yunxiu Zeng, Ruixian Wang, Xiaogang Qiu

Journal of System Simulation

Abstract: The paper studiesthe comprehensive military contests which are held frequently among military universities. Different from the qualitative analysis methods before, an analytic hierarchy process model is set up to analyze the effects which training programs have on students. A great amount of data is put into the entropy model to analyze the rationality of AHP model. This paper also sets the effect value as the input data of the emulating model to simulate the whole exercise process before contests which can verify the results received from AHP and entropy models. Research findings are helpful for superior leaders to make …


Modeling Of Nonlinear Industrial System At All Operating Conditions Based On State Tracking, Dong Ze, Erxin Yin Jan 2019

Modeling Of Nonlinear Industrial System At All Operating Conditions Based On State Tracking, Dong Ze, Erxin Yin

Journal of System Simulation

Abstract: From the prospective of industrial big data modeling, this paper presents a modeling method for nonlinear industrial system at all operating conditions based on state tracking. In view of large amount of historical data and the difficulty to screen the modeling data, a sliding window is designed to screen steady-state data. The fast calculation method for the standard deviation is deducted. The influence mechanism of unknown disturbance on the system is analyzed. The data segment, representing the system from dynamic state to stable state, is selected as the modeling data. A data-driven modeling algorithm, which can effectively eliminate the …


A Novel Algorithm For Improving Fairness Between Uplink And Downlink Flows In Heterogeneous Network, Peiyu Li, Zheqing Li, Wang Hui, Xia Qian Jan 2019

A Novel Algorithm For Improving Fairness Between Uplink And Downlink Flows In Heterogeneous Network, Peiyu Li, Zheqing Li, Wang Hui, Xia Qian

Journal of System Simulation

Abstract: In order to improve the fairness between uplink and downlink flows in AP optimization, a novel algorithm called FOUD(fairness over uplink and downlink) is proposed.Considering the influence of the attempt limit and the bit error rate of wireless, the FOUD algorithm modeling of AP and wireless stations is studied separately by using two-dimensional Markov chain, which derives the probability of data sending under the condition of different bit error rate and different number of uplink and downlink flows. Simulation results show that FOUD can improve the fairness of the uplink and downlink bandwidth as well as the …


High Order Numerical Method For System Of Fractional Differential Equations, Luan Xin, Xin Jia, Dalei Song, Weijia Zhao Jan 2019

High Order Numerical Method For System Of Fractional Differential Equations, Luan Xin, Xin Jia, Dalei Song, Weijia Zhao

Journal of System Simulation

Abstract: A spectral deferred correction method for classical ordinary differential equations is extended and reconstructed to solve a system of fractional differential equations (FDES) by accelerating the convergence of lower order schemes. Based on the residual function and the error equation deduced from Volterra integral equations equivalent to the fractional differential equations, a new high order numerical method for a system of FDES is constructed according to the idea of spectral deferred correction. The proposed method allows that one can use a relatively few nodes to obtain the high accuracy numerical solutions of FDES without the penalty of a …


A Method Of 3d Scattering Center Extraction Based On Multiple Hrrp Series, Cui Shan, Li Sheng, Yan Hua Jan 2019

A Method Of 3d Scattering Center Extraction Based On Multiple Hrrp Series, Cui Shan, Li Sheng, Yan Hua

Journal of System Simulation

Abstract: Scattering center extraction is the key content in the research of radar target characteristics, particularly the sliding type of scattering center. An extraction method based on the parametric scattering center model is proposed, which takes advantage of Hough transformation to extract geometric location and sliding radius parameters. The distance is gotten in the line of radar sight, and the useful information is obtained from high-resolution range profile (HRRP) series, which estimates size parameter of scattering centers and accomplishes signal reconstruction. This method solves the problems of point and sliding scattering center extraction. Simulation example manifests the applicability of the …


Invulnerability Simulation Analysis Of Compound Traffic Network In Urban Agglomeration, Chengbing Li, Wei Lei, Tianwei Lu, Gao Wei Jan 2019

Invulnerability Simulation Analysis Of Compound Traffic Network In Urban Agglomeration, Chengbing Li, Wei Lei, Tianwei Lu, Gao Wei

Journal of System Simulation

Abstract: To ensure the security operations of urban agglomeration transportation system, the perspective on compound network is used to explore the invulnerability of urban agglomeration traffic network. The site mapping method is used to build the model of weighted compound traffic network in city agglomeration. The traditional invulnerability metrics is revised and the attack strategies are determined according to the structure of the network. Hu-Bao-E city agglomeration is taken as an example to build the weighted compound traffic network model which is composed of road network and rail transit network, simulating the invulnerability and identifying key nodes in the …


Fault Detection Based On Gpnmf For Industrial Process, Yuguang Niu, Shilin Wang, Zhongwei Lin, Xiaoming Li Jan 2019

Fault Detection Based On Gpnmf For Industrial Process, Yuguang Niu, Shilin Wang, Zhongwei Lin, Xiaoming Li

Journal of System Simulation

Abstract: As a newly dimension reduction technique, non-negative matrix factorization (NMF) has been applied in varying research areas. NMF methods require the original data non-negative. However, the operating data of industrial process maybe not satisfy this restriction. To resolve the problem, a new method is presented, which can be called as generalized projection non-negative matrix factorization (GPNMF). We use GPNMF to extract the latent variables that drive a process and to combine them with process monitoring techniques for fault detection. The corresponding contribution plots are defined for fault isolation. The proposed method is applied to a 1 000 MW unit …


Forestry Fire Spatial Diffusion Model Based On Multi-Agent Algorithm With Cellular Automata, Guoxiong Zhou, Wu Qi, Aibin Chen Jan 2019

Forestry Fire Spatial Diffusion Model Based On Multi-Agent Algorithm With Cellular Automata, Guoxiong Zhou, Wu Qi, Aibin Chen

Journal of System Simulation

Abstract: In view that forestry fire has the nature of multi-phase and multi-component, a forestry fire spatial diffusion model based on multi-agent algorithm with cellular automata is proposed. A method based on Wang Zhengfei-CA model is employed to approximately simulate the spread of forestry fire. On the basis of the status transition rule determined by CA and using the self-learning and variation methods of multi-agent algorithm, the measured forestry fire pattern is most similar to CA rule-driven evolution model and the CA rule can be automatically optimized. By comparatively analyzing the simulation results of the traditional Rothermel model and the …


A Simulation Study Of Appointment Rulesin Ct Department, Li Jun, Xuemei Lin, Zhou Jie Jan 2019

A Simulation Study Of Appointment Rulesin Ct Department, Li Jun, Xuemei Lin, Zhou Jie

Journal of System Simulation

Abstract: A discrete event simulation model was established onExtendSimsoftware, , with the average patient waiting time, average idle time of the examination rooms and total cost which wasthe linearlyweighted sum of them being as performance measures.Estimated value and sample data of these performance measures of 9 basic appointment scheduling rules and 9 adjusted ones were produced by the de-duplication methodso that analysis of variance and efficient frontier were carried out to compare the effects of different “staggered reservation rules” on this queuing system.It was showed that, for different beneficiaries (patients, hospital or both), the appointment scheduling rules …


Simulation Of Missile Head Cover Separation And Landing Locations, Tian Hao, Mu Zhou, Huitong Li, Zhao Yang Jan 2019

Simulation Of Missile Head Cover Separation And Landing Locations, Tian Hao, Mu Zhou, Huitong Li, Zhao Yang

Journal of System Simulation

Abstract: Some missiles use head cover to protect the internal equipment during the launching process. In order to prevent the head cover from damaging the people or equipment after separation, researchers need to predict the landing position range and take protective measures. This paper designs a separation scheme for a missile head cover separation based on solid propellant gas generator and solid rocket. In this study, we establish a dynamic simulation model of head cover separation and falling procedure. The simulation calculation of the head cover location range considering multiple factors using Monte-Carlo method is developed. And the motional …


A Mppt Control Method Of Wind Turbines With Nonsingular And Fast Terminal Sliding Mode, Dazhong Li, Wu Feng Jan 2019

A Mppt Control Method Of Wind Turbines With Nonsingular And Fast Terminal Sliding Mode, Dazhong Li, Wu Feng

Journal of System Simulation

Abstract: In order to improve the energy capture efficiency of doubly-fed induction generator (DFIG), a control method is designed based on direct speed control (DSC) to achieve maximum power point tracking (MPPT). An effective wind speed estimator based on high-degree cubature Kalman filter (HCKF) and Newton-Raphson method (NR) is proposed for solving the difficulty in obtaining effective wind speed using traditional control strategy. A speed controller based on nonsingular fast terminal sliding mode surface is designed to obtain a faster speed response for the speed loop. The numerical simulation research of the 2.4MW wind turbine under rapidly variable wind …


Interval Fuzzy Modeling Based On Minimizing-Norm On Approximation Error, Xiaoyong Liu, Zhonggang Xiong, Changguo Yan Jan 2019

Interval Fuzzy Modeling Based On Minimizing-Norm On Approximation Error, Xiaoyong Liu, Zhonggang Xiong, Changguo Yan

Journal of System Simulation

Abstract: As the obtained data in many practical applications tend to be uncertain or inaccurate, conventional modeling methods characterized by deterministic model for this type of data have become undesirable. Taking linear programming and TS fuzzy model and some ideas from norm minimization into consideration, a novel method identifying interval fuzzy model (INFUMO) consisting of upper and lower TS fuzzy model (referred to as fU and fL) has been studied. In order to solve INFUMO, optimization problems based on minimizing-norm with respect to approximation error corresponding to fU and fL are constructed. Finally, optimization problems …


Optimization Via Simulation Based On Neural Network, Shihui Wu, Xiaodong Liu, Shao Yue, Zhang Fa, Minxiang Yang Jan 2019

Optimization Via Simulation Based On Neural Network, Shihui Wu, Xiaodong Liu, Shao Yue, Zhang Fa, Minxiang Yang

Journal of System Simulation

Abstract: To improve the efficiency of optimization via simulation (OvS), an OvS method based on neural network is proposed. Taking advantage of the approximation ability of neural network to nonlinear input-output relationship, neural network's outputs are used as substitutes for simulation results to reduce the required simulation runs. Samples are generated by simulation according to the three proposed samples selection methods. Owning to its advantages on learning speed, network stability and parameters selection, generalized regression neural network (GRNN) is adopted to train the samples. The trained GRNN forms a regression surface that represents the relationship between simulation inputs and outputs, …


Optimization Of Q-Btgsid Based On Sensitivity Analysis, Shuwei Jia Jan 2019

Optimization Of Q-Btgsid Based On Sensitivity Analysis, Shuwei Jia

Journal of System Simulation

Abstract: In order to make up for the defect that relative degree of incidence, absolute degree of incidence and synthetic degree of incidence are limited in the range of (0.5, 1], this paper attempts to improve the degree of grey incidence. A control factor of “λ” and the metric space are set up to adjust. A new model is established and its specific properties are studied. It is proved that the new model satisfies the grey incidence axioms and the range of degree of grey incidence can be extended to (0, 1]. We put forward four principles of …


Numerical Simulation Of Moisture Diffusion Of Composite Solid Propellant, Yufeng Wang, Gaochun Li, Xudong Zhang, Qu Kai, Jinfei Li Jan 2019

Numerical Simulation Of Moisture Diffusion Of Composite Solid Propellant, Yufeng Wang, Gaochun Li, Xudong Zhang, Qu Kai, Jinfei Li

Journal of System Simulation

Abstract: In order to elucidate the humidity aging mechanism of composite solid propellant, the diffusion and the distribution of moisture inside the composite solid propellant under humidity was evaluated through the hygroscopic test of propellant. The mathematical and the FE model of moisture diffusion were proposed. The FEM was employed to simulate the moisture diffusion inside propellant. Moreover, the factors that affect the moisture diffusion were analyzed. The results showed that the humidity FEM can be used to simulate the hygroscopic process inside propellant. The temperature can affect the moisture diffusion. The higher the temperature is, the greater the …


Application Of Wavelet Transform In Simulation Model Validation Of Outboard Active Decoy, Hongxi Zhang, Zhang Jie Jan 2019

Application Of Wavelet Transform In Simulation Model Validation Of Outboard Active Decoy, Hongxi Zhang, Zhang Jie

Journal of System Simulation

Abstract: Aiming at the characteristics that the output signal of outboard active decoy simulation model is non-stationary random signal, a simulation model verification method based on wavelet transform is proposed. The measured and simulated signals are decomposed into low frequency and high frequency parts by determining the wavelet function. For the low frequency part with stationary state, the characteristic data is obtained by parameter fitting with the least square method. For the high frequency part, AR model is used to fit the parameters, and the fitting parameters are used as the characteristic data, The correlation coefficient method is used to …


Simulation Of Cyber-Physical Systems Of Systems:Some Research Areas -Computational Understanding, Awareness, And Wisdom, Tuncer Ören Jan 2019

Simulation Of Cyber-Physical Systems Of Systems:Some Research Areas -Computational Understanding, Awareness, And Wisdom, Tuncer Ören

Journal of System Simulation

Abstract: After a brief emphasis about the interconnected world, including Cyber-Physical Systems of Systems, the increasing importance of the decision-making by autonomous, quasi-autonomous, and autonomic systems is emphasised. Promising roles of computational understanding, computational awareness, and computational wisdom for better autonomous decision-making are outlined. The contributions of simulation-based approaches are listed.


Multiple-Attribute Entity Recommendation Based On Classification, Meina Song, Xuejun Zhao, Haihong E Jan 2019

Multiple-Attribute Entity Recommendation Based On Classification, Meina Song, Xuejun Zhao, Haihong E

Journal of System Simulation

Abstract: In the process of exploring entity recommendation, the entity containing diverse attributes has gained more and more attention. Most of the current researchers mainly select one attribute, and embody it in the related algorithms and their extensions even though the entity is combined with multiple attributes in entity recommendation. In this paper, on the basis of the classification method, we delve into physical properties of the recommended entities, divide entity’s attribute information network into multiple sub ones. In sub information network, bounded by the amount of attributes, the single attribute and even multiple attributes can be diverted into diverse …


An Autonomous Cognitive Model Simulating Basal Ganglia Mechanism, Zongshuai Li, Chen Jing Jan 2019

An Autonomous Cognitive Model Simulating Basal Ganglia Mechanism, Zongshuai Li, Chen Jing

Journal of System Simulation

Abstract: Aiming at autonomous cognition problem, applying the winner-takes-all(WTA) learning mechanism, using cortical-striatal synaptic modification principle in basal ganglia, as well as based on the operant conditioning reflex theory, the basal ganglia autonomous cognitive model is established, which is suitable for the cognitive learning with limited actions. Skinner's pigeons experiment was simulated by applying this bionic learning model, which showes a gradual process of adaptive learning. The simulation results reflect that the proposed cognitive model is effective and can be used in the balance learning for a self-balancing robot. In the premise of unknown robot mathematical model, the purpose of …


Multi-Scale Representation Of Battlefield Situation, Yafeng Huang, Xudong Li, Hangfeng Zhang Jan 2019

Multi-Scale Representation Of Battlefield Situation, Yafeng Huang, Xudong Li, Hangfeng Zhang

Journal of System Simulation

Abstract: This paper studies the multi-scale representation of battlefield situation at the conceptual level in different aspects, such as the concept of situation scale, scale transformation and typical styles of multi-scale representation. The scale of battlefield situation as the Cartesian product of two sets is defined, in which the first set contains space, time, and semantics; the other set contains breadth, granularity, and ratio. The scale transformation is classified into two types: scale downward and scale upward. The scale transformation is decomposed into three basic operations, i.e. breadth transformation, transformation and visualization derivation. The study points out that FIOP, LOD …


Evaluation Of Simulation Credibility Based On Rough Set And Gray Correlation Analysis, Huibo Liu, Yongjie Qian Jan 2019

Evaluation Of Simulation Credibility Based On Rough Set And Gray Correlation Analysis, Huibo Liu, Yongjie Qian

Journal of System Simulation

Abstract: The evaluation of simulation model credibility has always been a hot issue in the simulation field. How to evaluate the credibility of the simulation is the key to the development of the simulation technology. It is of great significance for our country to carry out the credibility evaluation research. In view of the issue, the grey correlation analysis theory and the related principles in rough set theory are analyzed and the simulation credibility evaluation model based on rough set and grey correlation analysis is proposed. The indiscernibility principle in rough set is used to assign the weight distribution of …


Modeling And Simulation Of The Crosstalk On Aircraft Arinc429 Data Bus, Xudong Shi, Ruowen Wang, Jialin Wang, Hongxu Zhao Jan 2019

Modeling And Simulation Of The Crosstalk On Aircraft Arinc429 Data Bus, Xudong Shi, Ruowen Wang, Jialin Wang, Hongxu Zhao

Journal of System Simulation

Abstract: Based on the theory of multi-conductor transmission line, the crosstalk between a single cable and a UTP (unshielded twisted pairs) cable was studied. The MATLAB and CST were employed to do the theoretical calculation and modeling respectively, and the comparison result proved the validity and accuracy of the proposed model. Based on the UTP model, the shielding layer was used to build the STP(shielded twisted-wire pairs) model according to the ARINC429 specification, and the crosstalk which caused by a large voltage transient happening on the adjacent power line on the aircraft was further analyzed. The distance and length of …


Simulation Of Stone Cutting Process Based On Adaptive Coupling Method, Yongjun Tian, Guolin Duan, Junguang Kang, Jianhua Gang Jan 2019

Simulation Of Stone Cutting Process Based On Adaptive Coupling Method, Yongjun Tian, Guolin Duan, Junguang Kang, Jianhua Gang

Journal of System Simulation

Abstract: Aiming at complex nonlinear dynamic behaviors of stone-cutting process with circular saw and handling large mesh deformation instability in FEM, according to brittle material fracture mechanism, an adaptive coupling algorithm was established for calculating the cutting process of circular saw-stone materials system. The results show that the material removal process is a process of intermittent cycle; the cutting force is zero at the beginning of the process, and the force increases rapidly when the blade contacts with the stone, then decreases, eventually varies in a stable fluctuation. According to von-Mises stress distributions of saw blade and stone, the easily …


Impact Of Rumor Spreading In A ‘Small World’ Social Network On Pricing Decision, Li Feng, Wei Ying Jan 2019

Impact Of Rumor Spreading In A ‘Small World’ Social Network On Pricing Decision, Li Feng, Wei Ying

Journal of System Simulation

Abstract: This paper adopts methodology of multi-agent based modeling to represent rumor spreading on small-world social network and to address impacts of rumor on pricing decision and profit of supplier. In the model, the process of rumor diffusion follows well-accepted ‘Susceptible-Infective-Removal’ (SIR) model. Simulation proved that mathematic analysis of SIR model overestimated the results of rumor diffusion while PageRank algorithm is a more ‘efficient’ method to choose the source node for rumor propagation according to all four proposed indicators. Sensitivity analysis of two parameters in SIR model, spreading rate and ignoring rate, indicates that the loss of profit will be …


Dynamic Suppression Method For Commutation Torque Ripple Of Brushless Dc Motors, Kun Xia, Tan Yuan, Bin Dong, Lu Jing Jan 2019

Dynamic Suppression Method For Commutation Torque Ripple Of Brushless Dc Motors, Kun Xia, Tan Yuan, Bin Dong, Lu Jing

Journal of System Simulation

Abstract: A dynamic suppression method for commutation torque ripple by employing a quasi-Z-source network was proposed, which reduced the torque ripple dynamically during the speed adjustment process in brushless DC motors (BLDCM). The phase resistance was taken into consideration and the mathematics model for the system was established. To suppress the commutation torque ripples timely and effectively, Uup and tup needed to be adjusted dynamically through the quasi-Z-source network while the speed and load changed. A simulation model to dynamically suppress the commutation torque ripple in BLDCM based on quasi-Z-source network was established by MATLAB/Simulink, and the feasibility …


Dynamic Characteristics Research Of Torsional Vibration Generator, Jialin Tian, Du Fan, Yonghao Zhu, Chuanhong Fu Jan 2019

Dynamic Characteristics Research Of Torsional Vibration Generator, Jialin Tian, Du Fan, Yonghao Zhu, Chuanhong Fu

Journal of System Simulation

Abstract: Aiming at poor drill ability and low rate of penetration during the drilling process, a torsional vibration generator is presented. The structure and the operational principle of the torsional vibration generator are analyzed according to the torsional theory. The relationships among the collision frequency,the amount of hydraulic hammer compression, the torque, the inlet pressure, and inlet flow are obtained on the basis of its dynamic model, which is established in light of the actual working condition. Compared with the example calculation, the experimental test verifies the accuracy and reliability of calculation method. The research results show that when the …