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Full-Text Articles in Physical Sciences and Mathematics

Modeling And Simulation Of Ship Maneuvering Motion Based On Non-Uniform Flow And Shallow Water Effect, Sichen Tong, Xiaoya Tang, Zhang Huan Jan 2019

Modeling And Simulation Of Ship Maneuvering Motion Based On Non-Uniform Flow And Shallow Water Effect, Sichen Tong, Xiaoya Tang, Zhang Huan

Journal of System Simulation

Abstract: To reflect and simulate the flow condition and ship attitude in mountainous river, a 3-DOF ship motion mathematical model based on open channel non-uniform flow and shallow water effect is put forward. Analysis of the numerical simulation shows that with the decrease of depth-draft ratio h/d, the ship direct navigation speed decreases, the shallow water effect and the turning diameter increases. Meanwhile, the Z motion fluctuation amplitude and the oscillation period increase with the decrease of h/d, which means the decrease of the rudder effect and maneuverability. Application of the model in a case study shows that the proposed …


Modified Fractional Order Sliding Model Control For Dc Speed Regulating System, Zhicheng Zhao, Zhitao Zhao, Jinggang Zhang, Xianjiao Zhao Jan 2019

Modified Fractional Order Sliding Model Control For Dc Speed Regulating System, Zhicheng Zhao, Zhitao Zhao, Jinggang Zhang, Xianjiao Zhao

Journal of System Simulation

Abstract: An improved fractional order sliding model control (FOSMC) is proposed for DC speed regulating system to eliminate static error easily caused by disturbance in sliding model control. Second order mathematical model is established through taking the derivative of first-order mathematical model of DC speed regulating system. The theory of fractional calculus is introduced to the switching function of sliding mode, and fractional sliding model is designed combining exponential reaching law and second order mathematical model. The control signal of voltage can be obtained through taking output of the controller and integrator in series. Stability analysis of the system is …


Relevance Analysis Of Deicing Parameters And Deicing Efficiency Of Aircraft Ground, Bin Chen, Liwen Wang Jan 2019

Relevance Analysis Of Deicing Parameters And Deicing Efficiency Of Aircraft Ground, Bin Chen, Liwen Wang

Journal of System Simulation

Abstract: Aircraft ground freezing could lead to potential danger and delay for flight. To alleviate these problems, the main method is to use the deicing fluids to clean ice or snow on the aircraft body, which lacks of reference of the deicing fluids parameters and efficiency. To study the effect of the deicing fluids parameters on the aircraft deicing efficiency, the deicing mechanism is analyzed.The black box mathematical model of the deicing process is generalized abstractly. The deicing process is divided into two subprocesses to establish the deicing model.The relevance between the deicing fluids parameters and deicing efficiency is studied …


Dynamics Of Microbubble Confined In Concave Wall In Ultrasound Filed, Jiwen Hu, Jiana Sun Jan 2019

Dynamics Of Microbubble Confined In Concave Wall In Ultrasound Filed, Jiwen Hu, Jiana Sun

Journal of System Simulation

Abstract: The interactions between an ultrasound contrast agent (UCA) microbubble and a concave surface can be applied to understanding of the response of the UCA near blood vessel wall in ultrasound field. A dynamics model of microbubble near a concave wall is presented by a virtual image method and the acoustic reflection effects of the surface. The dynamic behavior of the microbubble is analyzed by numerical calculation. The results show that the microbubble vibration is suppressed near the wall. Inhibitory effects to microbubble vibration near rigid wall are stronger than that of near elastic wall. The microbubble vibration is easier …


Modeling Of Submarine Torpedo-Launching Simulation, Jinping Wu, Junchao Mao, Wenqiang Ding Jan 2019

Modeling Of Submarine Torpedo-Launching Simulation, Jinping Wu, Junchao Mao, Wenqiang Ding

Journal of System Simulation

Abstract: In order to lay foundation for modeling and simulation of operation problems such as torpedo attacking, torpedo operation application and torpedo operation effectiveness analysis, etc., the model of submarine torpedo-launching is built in the way of qualitative analysis and classical mathematics. As an important composition of submarine torpedo-attacking, torpedo-launching mainly means the course from torpedo out-tube to hitting target or voyage end, which is between the stage of “controlling weapon launching” and “observing attack effectiveness” during the whole torpedo-attacking course. Through analyzing the seven-stage trajectory process of torpedo-launching, the target detecting model and acoustic homing range model of …


A New Method On Trajectory Planning For Mobile Robots Using Bezier Curves, Sun Lei, Lishuang Zhang, Zhou Lu, Xuebo Zhang Jan 2019

A New Method On Trajectory Planning For Mobile Robots Using Bezier Curves, Sun Lei, Lishuang Zhang, Zhou Lu, Xuebo Zhang

Journal of System Simulation

Abstract: In view ofthe trajectory planning for the mobile robots, an efficient method based on Bezier curves is proposed, which produces better solution with shorter path and faster trajectory, compared with the existing methods. The problem of trajectory planning is divided into path planning and velocity planning. A Bezier curve is used to connect each two line-segments to obtain shorter paths. It is proved that the order of the used Bezier curves is at least five to ensure the curvature continuity of the whole path. Taking a differential-driven wheeled mobile as an example, to follow the planned path steadily and …


Research On Two-Dimensional Imaging Algorithm Of Tomography For Near-Field Radiation Of Rf Objects, Shaohui Quan, Changtai Shi, Xuwang Cui, Bin Shi Jan 2019

Research On Two-Dimensional Imaging Algorithm Of Tomography For Near-Field Radiation Of Rf Objects, Shaohui Quan, Changtai Shi, Xuwang Cui, Bin Shi

Journal of System Simulation

Abstract: Two two-dimensional imaging algorithms of tomography are presented for observing different sections of RF objects. Two-dimensional images of the cross and coronal sections of the model are obtained based on the near-field radiation data calculated by FEKO. The effects of different variables on the imaging resolution are studied by changing near field scanning points and distance between the observation plane and RF objects. After the analysis of the simulation results, the proposed algorithms are compared with other imaging algorithms from different aspects. The advantages and limitations are discussed. The change of images and the corresponding solution are studied …


Vibration Simulation And Damping Ratio Optimization Of Seat Suspension System For High-Speed Rail, Changcheng Zhou, Yuewei Yu, Leilei Zhao Jan 2019

Vibration Simulation And Damping Ratio Optimization Of Seat Suspension System For High-Speed Rail, Changcheng Zhou, Yuewei Yu, Leilei Zhao

Journal of System Simulation

Abstract: According to the 1/4 body-seat vertical vibration model of high-speed rail, an optimal design simulation model for damping ratio of seat suspension was established. An optimal design mathematical model for damping ratio of seat suspension was built with the optimal ride comfort as the target. Taking the track vertical irregularity as input and the seat suspension vertical stroke as constraint condition, an optimization design method for damping ratio of seat suspension based on track excitation was presented. With a practical example, the damping ratio was designed and validated by simulation. The results show that the damping ratio value …


Optimal Control And Simulation Of Hard Shoulder Running On Highways, Ruimin Li, Ye Zhen, Bin Li Jan 2019

Optimal Control And Simulation Of Hard Shoulder Running On Highways, Ruimin Li, Ye Zhen, Bin Li

Journal of System Simulation

Abstract: This paper summarizes the problems in the operation of hard shoulder running (HSR). A new algorithm for optimizing HSR on highways is proposed, which aims to minimize the total time spent (TTS) in the whole network. Based on the METANET model of highways, the algorithm utilizes genetic algorithm and sliding windows technique to forecast and optimize the operation of HSR under different constraint conditions and target functions. The strategy is tested on the I-80E highway in California. The experimental results show that when the change frequency of HSR is less than or equal to 14 during a sliding window …


Smooth Transition Method Over Entire Speed Range Of Switched Reluctance Motor, Diansheng Sun Jan 2019

Smooth Transition Method Over Entire Speed Range Of Switched Reluctance Motor, Diansheng Sun

Journal of System Simulation

Abstract: In order to smoothly switch different control modes of switched reluctance motor under the condition of low speed and high speed, a novel scheme using function fitting method to control turn-on angle, turn-off angle and phase current chopping is proposed. The active disturbance rejection speed control system is structured for switched reluctance motor in order to restrain all kinds of disturbance and improve the dynamic performance. Simulation results indicate that the principle of the method is correct and the turn-on angle, turn-off angle and phase current chopping is coordinated to realize the smooth switching of different control modes with …


Formation Mechanism And Simulation Analysis Of Railgun Armature Electromagnetic Transition, Zhiheng Wang, Wan Mei, Xiaojiang Li Jan 2019

Formation Mechanism And Simulation Analysis Of Railgun Armature Electromagnetic Transition, Zhiheng Wang, Wan Mei, Xiaojiang Li

Journal of System Simulation

Abstract: Armature transition of railgun causes rails erosion and change of launching parameters, which is one of the key problems restricting the performance of railgun. The formation mechanism of armature transition at the down-slope of driving current is analyzed. The armature transition estimation model and electromagnetic parameters calculation model are given. The formation process of armature transition at the down-slope of driving current is simulated by AYNSYS Workbench. The current and magnetic field distribution are simulated, so as the armature deformation caused by the armature electromagnetic force. The effect of current dropping rate on armature transition is analyzed. The …


Integrated Simulation Of Mixed Traffic Flow On Elementary And Middle School Gate’S Road When Students Going To School, Mingbao Pang, Yanan Pei, Zhang Ning Jan 2019

Integrated Simulation Of Mixed Traffic Flow On Elementary And Middle School Gate’S Road When Students Going To School, Mingbao Pang, Yanan Pei, Zhang Ning

Journal of System Simulation

Abstract: Synthesizing the advantages and disadvantages of social force model (SFM) and cellular automaton model (CAM), a simulation model of mixed traffic flow including pedestrian, motor vehicle and non-motorized vehicle on the interference road section of elementary and middle school’s gate when students going to school was established. The traffic flow characteristics after changing the proportion of students going to school by private car and implementing different traffic organization schemes were analyzed. The results of the examples indicate that its organization phenomena can be realized by decreasing the proportion of pupils taking private cars and implementing different measures of traffic …


A Method Of Finding The Shortest Path Of Dynamic Networks, Lunwen Wang, Zhang Ling Jan 2019

A Method Of Finding The Shortest Path Of Dynamic Networks, Lunwen Wang, Zhang Ling

Journal of System Simulation

Abstract: We analyze the research status of finding the shortest path of dynamic networks, analyze the complexity of getting the shortest path, study the relationship between the structure of the dynamic networks and finding the shortest path of the dynamic networks. It is proved that dynamic networks defined by velocity automatically meet weak FIFO’s condition. The networks whose passing function of any side is not decreasing function equals dynamic networks which use velocity. The sufficient condition of directly using Dijkstra algorithm to get the shortest path is that the networks must meet weak FIFO’s condition. How to build a …


Review On Modeling And Simulation Of Cyberspace Operation, Guangya Si, Zhang Yang, Yanzheng Wang Jan 2019

Review On Modeling And Simulation Of Cyberspace Operation, Guangya Si, Zhang Yang, Yanzheng Wang

Journal of System Simulation

Abstract: Modeling and Simulation (M&S) is the effective and indispensable method to research cyberspace operation. On the view of joint operation level, the evolution feature of the cyberspace operation M&S is analyzed, which includes the constructions of the cyberspace weapons range, the cyberspace operation concept environment, and the cyberspace operation command information system. The progress of the cyberspace operation M&S is introdeced, including the networked information environment, the entity, the action and the effection. The new challenges of the cyberspace operation M&S are analyzed from the military angle and technology angle.


Dynamic Decision-Making Modeling For Army Operation Command Post Entity, Kang Kai, Yongliang Zhang, Chenxi Li, Jintang Pan Jan 2019

Dynamic Decision-Making Modeling For Army Operation Command Post Entity, Kang Kai, Yongliang Zhang, Chenxi Li, Jintang Pan

Journal of System Simulation

Abstract: The paper presents a modeling method of dynamic decision-making for army operation command post entity based on the Bayesian Net (BN) to meet the demands of demonstrating the operational blue print and evaluating the plan with the support of subject matter experts and military rules. The method brings about the structured description for the decision-making rules, builds the BN model for battlefield situation, and actualizes the situation estimation based on the model of BN reasoning. Therefore it gives the reasonable analysis, the in-depth understanding and right dynamic estimation to the land battlefield dynamic situation, which embodies the complexity and …


Multi Criterion Variable Weight Comprehensive Evaluation Method Of Guidance And Control System, Yuxiao Wang, Songyan Wang, Chao Tao, Yang Ming Jan 2019

Multi Criterion Variable Weight Comprehensive Evaluation Method Of Guidance And Control System, Yuxiao Wang, Songyan Wang, Chao Tao, Yang Ming

Journal of System Simulation

Abstract: The evaluation of guidance and control system is necessary in the process of vehicle development. In view of lacking of effective comprehensive evaluation methods and the corresponding auxiliary software, the performance evaluation methods of vehicle guidance and control systems are researched, the structure of the system is analyzed, and a hierarchical performance evaluation index system is established. Considering the varying degrees of the data reliability and independence of each index, a variable-weight comprehensive method with multi-criteria is proposed. A performance evaluation example of vehicle guidance and control system is given which shows that the proposed method weights the …


Simulation Of Taxi Passenger Travel Mode Considering The Influence Of Online Booking Taxi, Cao Yi, Yanjin Li, Luo Xia Jan 2019

Simulation Of Taxi Passenger Travel Mode Considering The Influence Of Online Booking Taxi, Cao Yi, Yanjin Li, Luo Xia

Journal of System Simulation

Abstract: To reflect a systematic account of the impact online booking taxi and cruise taxi under the condition of information, the travelling mode choice of taxi passengers was researched. The influence factors of travelling mode choice of taxi passengers were analyzed and the time values related to passenger’s own characteristics were evaluated. The functions of waiting time of online booking taxi passengers and cruise taxi passengers were formed by investigating the difference of searching behavior. Through using simulation method, the priority for online booking taxi, cruise taxi and private cars was obtained .The results showed that the online booking …


Simulation Of Migration Of Hexavalent Chromium In Groundwater, Liu Ling, Liping Xiao, Xilin Li Jan 2019

Simulation Of Migration Of Hexavalent Chromium In Groundwater, Liu Ling, Liping Xiao, Xilin Li

Journal of System Simulation

Abstract: Taking chromite ore processing residue site in Shenyang city of Liaoning province as a research object, the static adsorption experiment and the dynamic soil column experiment were carried out, and the adsorption characteristics and the migration law for hexavalent chromium of chromite ore processing residue leachate were analyzed in the groundwater system. A coupled dynamic mathematical model was developed for simulating hexavalent chromium migration in the groundwater system. Numerical simulation of hexavalent chromium migration in groundwater for 40 years before the anti-seepage measure and for 60 years after the anti-seepage measure was completed by using Visual Modflow software. The …


Health Warning And Fault Diagnosisof Pulverizing System Based On Syncretic Similarity, Songming Jiao Jan 2019

Health Warning And Fault Diagnosisof Pulverizing System Based On Syncretic Similarity, Songming Jiao

Journal of System Simulation

Abstract: It is an arduous task to know health statusof a pulverizing system in power plant by monitoring these parameters simultaneously and the fault diagnosing process is complicated.An approach based on syncretic similarity is presented which is suitable for industrial system’s health warning and fault diagnosis.The syncretic similarity couples anew type of weighted mahalanobis distance based on principal component analysiswith an improved weighted sine similarity. The approachhas self-learning ability.Central parameterswhich are used to compute similarity can be modified along with the operation process.Simulation resultsshow that the method is suitable for online application because of its high accuracy, fast …


Cfd-Based Research On The Erosion Of The Fracturing Pump Valve Structure, Mo Li, Xiaobing Wang, Wang Jun, Guangcai Zhuang Jan 2019

Cfd-Based Research On The Erosion Of The Fracturing Pump Valve Structure, Mo Li, Xiaobing Wang, Wang Jun, Guangcai Zhuang

Journal of System Simulation

Abstract: In view of the characteristic of severe erosion and abrasion in the fracturing pump valve, CFD-based erosion and failure is simulated and computed. The distributed rule of the pump valve lift, times of stroke, the height of the seal and the sealing contact length at a certain moment are shown. By analyzing the characteristic of the flow field from the simulated result and the failure mechanism of the fracturing pump valve, it is concluded that the lift is smaller, the greater is the flow velocity, the high times of stroke will increase the flow rate and the lag …


Modeling And Control Of Networked Control Systems With Partitioned Random Delay, Yicai Liu, Bin Liu, Anwei Shi Jan 2019

Modeling And Control Of Networked Control Systems With Partitioned Random Delay, Yicai Liu, Bin Liu, Anwei Shi

Journal of System Simulation

Abstract: As for a class of networked control systems which have the bilateral random delay of sensor-to- controller and controller-to-actuator, the networked control systems were modeled as discrete-time jump systems with uncertain parameters by firstly partitioning the maximum possible delay value into a plurality of equal intervals, and then describing it as a stochastic process of a finite state Markov chain according to the jump characteristics of the delay in each interval. Considering the condition that the elements of the transition probability matrix of the Markov chain were partly unknown, the time-varying controller meeting the requirement of system stability was …


Spectralwidth Selection And Detectability Analysis Ofstarlight Refraction Sensor, Xianzhong Wang, Liu Yu, Minlan Tang, Limin Zhang Jan 2019

Spectralwidth Selection And Detectability Analysis Ofstarlight Refraction Sensor, Xianzhong Wang, Liu Yu, Minlan Tang, Limin Zhang

Journal of System Simulation

Abstract: Aiming at the engineering problem of starlight refraction sensor’s ability fordetecting the starlight refracted in atmosphere, the atmospheric attenuation coefficient of the visible and near infrared stellar dueto dispersion, molecular scattering, ozone absorption and so on are analyzed, which determines starlight refraction sensor’s spectral width and the visual magnitude difference equivalent with narrow spectral detection.The starlight refraction sensor’s detection ability and detection probability are estimatedbased on signal to noise ratio calculation and SNRanalysis. The simulation results give the visual magnitude difference equivalent with the atmospheric attenuation to the different atmospheric altitude, and the limiting magnitude of the different temperature …


Situation Assessment Approach For Air Defense Operation System Based On Force-Sparsed Stacked-Auto Encoding Neural Networks, Shengming Guo, Xiaoyuan He, Wu Lin, Xiaofeng Hu Jan 2019

Situation Assessment Approach For Air Defense Operation System Based On Force-Sparsed Stacked-Auto Encoding Neural Networks, Shengming Guo, Xiaoyuan He, Wu Lin, Xiaofeng Hu

Journal of System Simulation

Abstract: Aiming at the difficulty of feature extraction and related generation mechanism analysis for complex Air Defense System of Systems (ADSOS) using traditional data mining method, a novel situation assessment approach based on Force-Sparsed Stacked-Auto Encoding Neural Networks (FS-SAE) is proposed. Combined with big data and complex networks technology, FS-SAE situation assessment model is built. The emergence relations between the capacity indexes of ADSOS are formalized. And then, the formation mechanism and the contribution rate of capacity indexes are studied and the validity of this approach is validated by the simulation data. The experimental results show that formalized presentation …


A Model For Battlefield Situation Change Rate Prediction Based On Deep Learning, Jiuyang Tao, Wu Lin, Wang Chi, Junda Chu, Liao Ying, Zhu Feng Jan 2019

A Model For Battlefield Situation Change Rate Prediction Based On Deep Learning, Jiuyang Tao, Wu Lin, Wang Chi, Junda Chu, Liao Ying, Zhu Feng

Journal of System Simulation

Abstract: To measure and estimate the uncertainty of the battlefield situation is of great significance for the commanders to plan the reconnaissance mission and reduce the risk of decision-making. Based on Shannon's information theory, firstly, methods and a model on measurement of situation change rate are proposed. Secondly, a scene with two-dimensional grid elements maneuvering is established, based on deep learning, the prediction method for maneuvering trend is explored. It is proved that cross entropy is equivalent to situation change rate. Finally, with the increase of the objective uncertainty, situation change rate and the accuracy of the forecast is …


Agent-Based Modeling And Simulation Approaches In Stem Education Research, Shanna R. Simpson-Singleton, Xiangdong Che Jan 2019

Agent-Based Modeling And Simulation Approaches In Stem Education Research, Shanna R. Simpson-Singleton, Xiangdong Che

Journal of International Technology and Information Management

The development of best practices that deliver quality STEM education to all students, while minimizing achievement gaps, have been solicited by several national agencies. ABMS is a feasible approach to provide insight into global behavior based upon the interactions amongst agents and environments. In this review, we systematically surveyed several modeling and simulation approaches and discussed their applications to the evaluation of relevant theories in STEM education. It was found that ABMS is optimal to simulate STEM education hypotheses, as ABMS will sensibly present emergent theories and causation in STEM education phenomena if the model is properly validated and calibrated.