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A Mesh Model Simplification Method Based On Visual Feature Preservation, Che Li, Dejun Tang, Shimin Li, Fengju Kang Dec 2019

A Mesh Model Simplification Method Based On Visual Feature Preservation, Che Li, Dejun Tang, Shimin Li, Fengju Kang

Journal of System Simulation

Abstract: Aiming at the problems of mesh visual feature loss and oversimplification in mesh simplification algorithm, a visual feature preservation based triangle mesh model simplification algorithm is proposed. The multi-viewpoint perception method is used to measure the visual perception error caused by the difference between the original and the simplified model in the two-dimensional view under the optimal viewpoint set. Based on QEM algorithm, a novel geometric error metric is built by introducing the triangle shape factor. The triangle collapse error function is defined by combining visual perception and geometric error to control the simplified depth of the model. Through …


Research On Intelligent Clustering Algorithm For Complex Water Wireless Network Surveillance, Hua Xiang, Hongtao Liang, Zhaoxin Dong, Wang Zhao, Hongjuan Yao, Baohua Li, Bingqing Jiang Dec 2019

Research On Intelligent Clustering Algorithm For Complex Water Wireless Network Surveillance, Hua Xiang, Hongtao Liang, Zhaoxin Dong, Wang Zhao, Hongjuan Yao, Baohua Li, Bingqing Jiang

Journal of System Simulation

Abstract: The clustering of irregular networks will cause load imbalance, which results in the phenomenon of “energy hot zone”. Aiming at the unreasonable topology of irregular network clustering, an intelligent clustering algorithm based on genetic strategy is proposed for the wireless network surveillance of complex water system. An irregular complex water topology model and an energy consumption model are built, and a genetic clustering strategy is designed via the principle of minimum energy consumption. The P matrix coding method is given, which avoids the squared increment of data calculation. Simultaneously, an adaptive genetic operator and a fuzzy modified operator are …


Moving Object Detection Based On Deep Convolutional Neural Network, Yuqiu Lu, Jinyu Sun, Shiwei Ma Dec 2019

Moving Object Detection Based On Deep Convolutional Neural Network, Yuqiu Lu, Jinyu Sun, Shiwei Ma

Journal of System Simulation

Abstract: A deep convolution neural network MONet is designed for the intermittent motion problem in moving objects detection. In the absence of training data sets, a synthetic dataset GoChairs is generated by affine transformation, and on this basis the network training and testing are performed. The results show that the trained MONet can effectively detect the moving objects based on the correspondence between the pixels. The traditional datasets CDnet and I2R are also tested to verify the generalization performance of the network. In addition, MONet is compared qualitatively and quantitatively with classical methods for the intermittent motion problem of …


Intelligent Fire Rescue Based On Internet Of Things And Virtual Reality, Fengting Yan, Zhicai Shi, Qianmin Su, Dong Jing, Jue Chen, Yunyu Shi, Tang Xian Dec 2019

Intelligent Fire Rescue Based On Internet Of Things And Virtual Reality, Fengting Yan, Zhicai Shi, Qianmin Su, Dong Jing, Jue Chen, Yunyu Shi, Tang Xian

Journal of System Simulation

Abstract: The integration of virtual reality, Internet of Things and artificial intelligence can provide intelligent WebVR interaction for fire rescue decision-making. However, it is necessary to solve the problems of data lightweight, real-time data transmission based on the Internet of Things, and visualization of fire scenario data on the web, and to build effective mechanisms and algorithms. This paper proposes an intelligent fire rescue (IVIFR) mechanism based on the integration of Internet of Things and Virtual Reality, gives a virtual intelligent fire rescue (VIFR) algorithm, and constructs a prototype system of intelligent fire rescue. The VIFR algorithm …


Modeling And Simulation Of Complex Equipment Health Management System Based On Cloud Computing, Tianrui Zhang, Chuansheng Qu, Baoku Wu, Jianan Xu Dec 2019

Modeling And Simulation Of Complex Equipment Health Management System Based On Cloud Computing, Tianrui Zhang, Chuansheng Qu, Baoku Wu, Jianan Xu

Journal of System Simulation

Abstract: For complex equipment operation safely, the health management problems of complex equipment life cycle is analyzed. In order to realize remote service, complex equipment health management mode based on cloud computing is proposed. Aiming at the accuracy problem in the process of extracting and recognizing complex equipment characteristic data, the feature knowledge acquisition method based on ontology is researched, and the expression and acquisition algorithm of state characteristic knowledge is proposed. A task sequencing algorithm faults based on fuzzy comprehensive evaluation method is proposed, an appropriate task assignment model is selected for scheduling health management technicians. …


Research On Eye Location And Head State Detection Based On Integrated Learning, Yingnian Wu, Mengjia He, Xiang Wei Dec 2019

Research On Eye Location And Head State Detection Based On Integrated Learning, Yingnian Wu, Mengjia He, Xiang Wei

Journal of System Simulation

Abstract: For real-time detection of eye location problem, a real-time detection system of human eye based on Viola Jones algorithm is designed. Through the MATLAB, the real-time reading and positioning of the detected human eye pictures are controlled by the external or webcam. Through side view, top view, and upward view, it is shown that the human eye real-time positioning system has good detection effect and robustness. In view of the poor classification effect of small data sets on the head state, the random forest algorithm is used to classify the pitching Angle and yaw Angle by HOG-LBP fusion feature …


Design And Finite Element Analysis Of Reflector Spherical Shell For Flight Simulator, Hailiang Bai, Jiang Nan, Zhang Liao, Yuewen Fu Dec 2019

Design And Finite Element Analysis Of Reflector Spherical Shell For Flight Simulator, Hailiang Bai, Jiang Nan, Zhang Liao, Yuewen Fu

Journal of System Simulation

Abstract: The fight simulator with six-degree-of-freedom motion platform can simulate the flight attitude in real time and provide realistic overload dynamic feeling, which requires that the equipment on the platform must adapt to the overload during flight simulation. To solve the contradiction between the rigidity and weight of material, the glass fiber composite material is used to design and manufacture the spherical shell of the mirror . To improve the optical collimation of the reflector, the specific hyperboloid aspheric surface is selected as the surface design scheme,the 3D model of the spherical shell is constructed. The parameters of the …


Simulation Of Vehicle Startup Delay At Green Light And Its Direct And Chain-Reaction Impact On Traffic Flow, Longxi Luo, Lijun Xie, Jianping Wu, Xu Ming Dec 2019

Simulation Of Vehicle Startup Delay At Green Light And Its Direct And Chain-Reaction Impact On Traffic Flow, Longxi Luo, Lijun Xie, Jianping Wu, Xu Ming

Journal of System Simulation

Abstract: In current traffic simulations, it is implicitly assumed vehicles are driven by ideal drivers. Therefore, simulated vehicles make the most reasonable decisions such as moving out immediately when traffic lights turn green, resulting in a gap between simulations and real traffics. Research shows that drivers, including those who follow the rules, show a delay in starting-up their vehicles at the green light. The vehicle startup delay (SUD) is even more significant for drivers by things such as cell phones during waiting. However, the SUD has rarely been considered in simulations. The SUD is simulated to study its impacts on …


Microscopic Simulation Based Evaluation Of Congestion Pricing For Beijing Urban Area, Jingchen Dai, Ruimin Li Dec 2019

Microscopic Simulation Based Evaluation Of Congestion Pricing For Beijing Urban Area, Jingchen Dai, Ruimin Li

Journal of System Simulation

Abstract: In order to study the potential effect of congestion charging policy in large-scale road network, a micro-simulation platform Paramics is used to establish a simulation model within Beijing fourth ring road. On this basis, multiple congestion pricing scenarios are assessed in consideration of charging zones size, charging rate, and travel mode shift. When the travel mode shift is put aside, the analysis shows that selecting a larger charging zone is more effective on reducing vehicle kilometers of travel and may increase the total charge revenue. However, congestion pricing appears no potential to significantly affect the average speed of …


Numerical Simulation Of Rock Breaking Mechanism For Compound Percussion Drilling, Yumei Li, Liwei Yu, Zhang Tao, Su Zhong, Jianming Liu Dec 2019

Numerical Simulation Of Rock Breaking Mechanism For Compound Percussion Drilling, Yumei Li, Liwei Yu, Zhang Tao, Su Zhong, Jianming Liu

Journal of System Simulation

Abstract: The ABAQUS dynamic impact module is used to establish the numerical calculation model for PDC single tooth-rock impact. The effects of PDC cutting teeth on the dynamic rock breaking mode and rock breaking effect under the combined action of rotating speed, drilling pressure, alternating impact torque and alternating impact force are studied. The study shows that the torsional impact mode is 39.28% higher than the rock breaking efficiency of the rotary impact, and the compound percussion mode is 27.79% higher than the rock breaking efficiency of the torsional impact. Under the same conditions of impact time, the rock surface …


Short-Term Wind Power Prediction Based On Improved Firefly Algorithm, Jiale Ding, Guochu Chen, Kuo Yuan Dec 2019

Short-Term Wind Power Prediction Based On Improved Firefly Algorithm, Jiale Ding, Guochu Chen, Kuo Yuan

Journal of System Simulation

Abstract: A wind power prediction model based on improved complementary set empirical mode decomposition and improved firefly algorithm to optimize echo state network is proposed to solve the problems of low accuracy in wind power with large randomness and strong volatility prediction of traditional echo state network prediction model. The wind speed series are decomposed into a series of intrinsic modes by using the improved complementary ensemble empirical mode decomposition. The new modes are used to predict wind power by using echo state network, the optimal weight of the model is found by the improved firefly algorithm. The output results …


Path Planning For Mobile Sink Based On Enhanced Ant Colony Optimization Algorithm In Wireless Sensor Networks, Shanshan Ji Dec 2019

Path Planning For Mobile Sink Based On Enhanced Ant Colony Optimization Algorithm In Wireless Sensor Networks, Shanshan Ji

Journal of System Simulation

Abstract: To reduce the energy consumption and sink mobile distance of mobile sink wireless sensor networks simultaneously, a path planning algorithm for mobile sink based on enhanced ant colony optimization algorithm in wireless sensor networks is proposed. Genetic operators are introduced to ant colony optimization algorithm in order to prevent ant colony optimization premature. The non-uniform of data distribution is considered as the constraint condition, the network lifetime and sink mobile distance are considered as a multi-objective problem, and the enhanced ant colony optimization is adopted to search the Pareto sub-optimal sets of rendezvous points. The simulation results show that …


Attitude Control Of Hypersonic Vehicle Considering Input Saturation, Xiaocen Liu, Yunjie Wu, Xu Peng Dec 2019

Attitude Control Of Hypersonic Vehicle Considering Input Saturation, Xiaocen Liu, Yunjie Wu, Xu Peng

Journal of System Simulation

Abstract: Aiming at the design of attitude control of hypersonic vehicles, the sliding mode disturbance observer is used to compensate the composite disturbance, meanwhile the dynamic surface control method is used to deal with the design of the nonlinear control system. Considering the input saturation problem, the control input is expanded into a new variable to design the controller, which is different from the direct limit of the rudder deviation. The simulation results show that the dynamic surface control method based on sliding mode observer has stronger robustness than the simple dynamic inversion control method, but the control inputs of …


Research On Extraction Method Of Time-Frequency Feature Of Fall Detection, Tianrun Wang, Su Zhong, Liu Ning, Li Chao, Guodong Fu Dec 2019

Research On Extraction Method Of Time-Frequency Feature Of Fall Detection, Tianrun Wang, Su Zhong, Liu Ning, Li Chao, Guodong Fu

Journal of System Simulation

Abstract: Aiming at the problem of features extract method for fall detection, the method using time-frequency analyze and features extraction by Fractional Fourier Transform (FRFT) has been proposed. The inertial data is measured by 15 IMU wearing on body, the features extracted after FRFT with multiple order are analyzed and compared. The difference of feature distribution of eight fall actions has been compared, and the difference of feature distribution between fall action and 4 normal actions has been compared. The feasibility of using FRFT in fall detection is proved.


Modeling Indoor Environment With Kinect, Lianrui Xu, Jinming Zhang Dec 2019

Modeling Indoor Environment With Kinect, Lianrui Xu, Jinming Zhang

Journal of System Simulation

Abstract: To solve the problems of point cloud noise, depth data mismatching and local details prone to hollowing in the process of Kinect camera reconstruction of indoor three-dimensional environment. By improving the assignment method of depth image pixel and the threshold relationship of time frame matching, this paper denoises the point cloud with optimizing mean filtering and time frame weighting methods. Combined with recent iteration algorithm (Iterative Closest Point, ICP) to complete the adjacent point cloud splicing so that it can achieve completely indoor model to build 3D environment. To test the validity of the algorithm, the experiment of …


Comparative Study On Resistance Modeling Method In Yacht Simulator, Xiaochen Li, Yin Yong Dec 2019

Comparative Study On Resistance Modeling Method In Yacht Simulator, Xiaochen Li, Yin Yong

Journal of System Simulation

Abstract: In order to solve the problem that the existing resistance modeling method of yacht has poor universality and the calculation accuracy is not high, approximate resistance modeling methods of high speed craft are analyzed and summarized. The actual yacht model is simplified into a prismatic hull. “ЦАГИ” method and SIT method are reproduced and the simulation results are compared with model test. The application of resistance approximate modeling in the yacht simulator is discussed. The results reveal that the resistance is in good agreement with the experimental value, and the SIT method with simplified hull form is more …


Lstm Model For Trajectory Design Of Missile-Borne Bfsar Imaging Guidance, Bohao Li, Yunjie Wu Dec 2019

Lstm Model For Trajectory Design Of Missile-Borne Bfsar Imaging Guidance, Bohao Li, Yunjie Wu

Journal of System Simulation

Abstract: In the multi-platform path planning of multi-missile cooperative guidance algorithm used for missile-borne Bi-static Forward-looking Synthetic Aperture Radar (BFSAR) imaging, it is necessary to plan and adjust the transmitter trajectory according to the space state of the receiver and the path constraints between the receiver and the transmitter.An effective LSTM model is constructed to study and train the trajectory path generated by the existing algorithms, and the direct mapping relationship between the receiver space state, path constraint and the trajectory of the transmitter is obtained. The simulation results not only show that LSTM is feasible in multi-missile path …


Noise Clipping Algorithm Based On Relative Contribution Rate, Shuoyu Liu, Yueming Dai Dec 2019

Noise Clipping Algorithm Based On Relative Contribution Rate, Shuoyu Liu, Yueming Dai

Journal of System Simulation

Abstract: This paper presents a class noise cutting algorithm (Class noise cutting, CNC) based on relative contribution rate. The algorithm calculates the relative contribution rate of features to the theme. The most valuable feature set is selected by using features distinguish rating. The corresponding candidate categories for each feature are selected, to reduece the candidate category set, improves the classification accuracy, and speed up the response speed of the classifier. Compared with another ECN noise cutting algorithm (Eliminating the class whose), CNC-has higher accuracy and because of its simpler feature dimension dictionary and better candidate category set, the response …


Study On Data-Driven Orca Preference Velocity, Wang Jie, Bin Chen, Yuan Peng, Ma Liang, Xiaogang Qiu Dec 2019

Study On Data-Driven Orca Preference Velocity, Wang Jie, Bin Chen, Yuan Peng, Ma Liang, Xiaogang Qiu

Journal of System Simulation

Abstract: Crowd evacuation is an important aspect of emergency management. Because of economic and safety reasons, emergency evacuation drill cannot be carried out repeatedly, however modeling and simulation has the obvious advantages of low cost, high repeatability, etc. Optimal Reciprocal Collision Avoidance (ORCA) is a velocity-based Collision Avoidance method, which has fine granularity and high computational efficiency, and is widely used in robot collision avoidance and other domains. In this paper, ORCA is introduced into crowd evacuation simulation, and the optimal parameters of ORCA under different kinds of speed strategies are identified by data-driven method. The optimal strategy …


Research On Supporting Action Model Of Long-Rang Strike Space Reconnaissance Based On Combination Mode, Changliang Xiao, Jingyu Yang, Wu Xi, Ma Jun, Xiaojing Yin Dec 2019

Research On Supporting Action Model Of Long-Rang Strike Space Reconnaissance Based On Combination Mode, Changliang Xiao, Jingyu Yang, Wu Xi, Ma Jun, Xiaojing Yin

Journal of System Simulation

Abstract: Space reconnaissance support operations mainly undertake the tasks of target detection and identification in the early stage of strike, target guidance during strike and damage effect evaluation after strike. Based on EBI(Entity, Behavior, Interaction)modeling framework, this paper describes the entity models of signal intelligence sensor, radar alarm sensor and imaging sensor, constructs a combined mode of space reconnaissance support operation. It mainly models the combined mode algorithm of three sensors and their respective target detection behavior rules, whick is conductive to improving reconnaissance efficiency and enhancing intelligence quality in combat operations.


Spatiotemporal Mode Analysis Of Urban Dockless Shared Bikes Based On Point Of Interests Clustering, Zhang Fang, Bin Chen, Yanghua Tang, Dong Jian, Chuan Ai, Xiaogang Qiu Dec 2019

Spatiotemporal Mode Analysis Of Urban Dockless Shared Bikes Based On Point Of Interests Clustering, Zhang Fang, Bin Chen, Yanghua Tang, Dong Jian, Chuan Ai, Xiaogang Qiu

Journal of System Simulation

Abstract: The city’s dockless shared bikes have developed rapidly, and its features of convenience, economy and efficiency have been widely welcomed. The digital footprint they generate reveals the movement of people in time and space within the city, which makes it possible to quantify the activities of people in the city using shared bikes. In this paper, based on the collected shared bikes data of Beijing, a clustering method based on the point of interests is proposed to divide the urban space, so as to construct a mobile network of urban shared bikes, and analysis the spatiotemporal mode of bike …


Design Of Feedback Linearization Nonlinear Controller For Asynchronous Motor Power Consumption Efficiency, Li Rui, Yingnian Wu Dec 2019

Design Of Feedback Linearization Nonlinear Controller For Asynchronous Motor Power Consumption Efficiency, Li Rui, Yingnian Wu

Journal of System Simulation

Abstract: In order to realize precise feedback linearization and optimal control of motor power consumption for MIMO nonlinear affine system, we build the model of induction motor within which dynamic power loss factor is included. Based on the differential geometry theory, a nonlinear optimization model of the controller is designed for this model to control the asynchronous motor outputs accurately and enhance the power efficiency. This paper presents an optimal control law for multiple inputs multiple outputs affine nonlinear system and the detailed design steps are given combined with examples for multiple outputs tracking problem. The simulation results show that …


The Scheduling Algorithm Of Cloud Job Based On Hopfield Neural Network, Yudong Guo, Jinping Zuo Dec 2019

The Scheduling Algorithm Of Cloud Job Based On Hopfield Neural Network, Yudong Guo, Jinping Zuo

Journal of System Simulation

Abstract: Focusing on the low efficiency of cloud job scheduling and the insufficient utility of resource, a job scheduling algorithm based on Hopfield Neural Network is proposed. In order to improve the resource scheduling ability of the system, The resource characteristics which influence the cloud job scheduling are shown. The mathematical model of resource constraints is established, and the Hopfield energy function is designed and optimized. The average utilization rate of 9 nodes is analyzed by using the standard test cases, and the performance and resource utilization of the proposed strategy are compared with three typical algorithms. …


Research On Gear Appearance Defect Recognition Based On Improved Faster R-Cnn, Weixi Ji, Du Meng, Peng Wei, Xu Jie Dec 2019

Research On Gear Appearance Defect Recognition Based On Improved Faster R-Cnn, Weixi Ji, Du Meng, Peng Wei, Xu Jie

Journal of System Simulation

Abstract: In order to achieve automatic identification of gear appearance defects and improve the qualification rate of gear products, aiming at the generalization of traditional defect recognition algorithms and the time-consuming of manual features extraction, this paper proposes an improved gear flaw detection algorithm for Faster R-CNN. VGG-2CF network is designed to improve the ability to identify smaller targets. Introducing AM-Softmax loss function is introduced to reduce the intra-class variation and optimize the inter-class difference. Combining with F-measure in machine learning algorithm, an AMF-Softmax loss function is proposed to solve the problem of data imbalance. The experimental results show the …


Overview Of Cooperative Target Assignment, Ou Qiao, Xiaoyuan He, Jiuyang Tao Dec 2019

Overview Of Cooperative Target Assignment, Ou Qiao, Xiaoyuan He, Jiuyang Tao

Journal of System Simulation

Abstract: The concept and connotation of combat coordination are briefly analyzed. The historical origin of cooperative target allocation and its orientation in command and control process are expounded. The research status of collaborative target allocation in model building and algorithm solving is analyzed comprehensively, the shortcomings of current research is pointed out. It is proposed that for the next step we should pay more attention to large-scale collaborative target allocation under dynamic and confrontational conditions, and focus on the real-time, adaptability and iterative evolution mechanism of the algorithm.


Knowledge Representation Method Of Joint Operation Situation Based On Knowledge Graph, Baokui Wang, Wu Lin, Xiaofeng Hu, Xiaoyuan He Dec 2019

Knowledge Representation Method Of Joint Operation Situation Based On Knowledge Graph, Baokui Wang, Wu Lin, Xiaofeng Hu, Xiaoyuan He

Journal of System Simulation

Abstract: Lacking of common knowledge for understanding and judging complex situation of operation by machines is one of the difficulties in intelligent situation cognition. The knowledge representation methods based on knowledge graph are reviewed. The characteristics and difficulties of joint operation situation knowledge representation are analyzed. Moreover, the concept of scenario knowledge graph is presented, as well as the knowledge sources and basic content of scenario knowledge graph are described. This paper also points out that the joint knowledge representation method based on discrete symbols and continuous vectors in specific scenario is an effective way to express joint operation situation …


Fast Simulation Of Yacht In Calm Water Based On Improved Savitsky Method, Xiaochen Li, Yin Yong Dec 2019

Fast Simulation Of Yacht In Calm Water Based On Improved Savitsky Method, Xiaochen Li, Yin Yong

Journal of System Simulation

Abstract: An improved Savitsky method is proposed to increase the accuracy of mathematical model of yacht in fast simulation. Three degrees of freedom mathematical model is established to simulate the motion in displacement regime. warped hull forms of yachts are simplified into prismatic hull and improved Savitsky method is used to calculate resistance. The simulation is carried out in pre-planing regime and planing regime. The validity of the proposed method has been assessed by comparing results with previous experimental data, which shows good agreements. The improved method runs well and the result is accurate when it is added to the …


Urban Functional Area Identification Method Based On Mobile Big Data, Xiao Di, Xiaoyong Zhang, Hu Yang Dec 2019

Urban Functional Area Identification Method Based On Mobile Big Data, Xiao Di, Xiaoyong Zhang, Hu Yang

Journal of System Simulation

Abstract: With the rapid development of urbanization, the function of urban land is constantly evolving. It is of great significance to identify urban functional areas in real time and accurately. In recent years, accompanied by the popularity of smart phones and the rapid development of the Internet, mobile phones have become sensors of human activities. In this paper, a method of urban functional area identification based on time series mobile phone data mining and POI semantics analysis is proposed. The time series feature of remaining mobile phone positioning is extracted facing block scale. And a FCM clustering algorithm based …


Design Of A Flexible System Simulation Evaluation Framework, Rusheng Ju, Zimin Cai, Wang Song, Wang Peng Dec 2019

Design Of A Flexible System Simulation Evaluation Framework, Rusheng Ju, Zimin Cai, Wang Song, Wang Peng

Journal of System Simulation

Abstract: To meet variable evaluation requirement of complex system simulation, this paper puts forward a design strategy of flexible effectiveness evaluation framework. The composition structure of system simulation evaluation framework is analyzed. To help users design reference dynamically, the method of evaluation reference edit and display is introduced based on Web. To enhance the extensibility of evaluation model, the method of interface design and code generation is investigated. To ensure the flexibility and extensibility of evaluation framework, the relation and mapping mechanism of evaluation references, evaluation model and evaluation result is studied. The framework is realized and verified in …


A Cloud Service Composition Optimization Based On Hnn, Huili Zhang, Zhihe Li Dec 2019

A Cloud Service Composition Optimization Based On Hnn, Huili Zhang, Zhihe Li

Journal of System Simulation

Abstract: With the rapid development of Cloud service application, how to effectively optimize the composition of Cloud services on cloud platform and improve the overall performance of cloud platform system have become an urgent research issue. In order to improve the efficiency of Cloud services, a combined optimization model based on Hopfield neural network is proposed. The problem of Cloud services is modeled. The problem is expressed as Hopfield Neural Network energy model for optimization, and a PSO group algorithm with Cauchy disturbance is designed to improve the Hopfield model. The experimental comparison shows that the method can improve …