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Full-Text Articles in Physical Sciences and Mathematics

Linear Array Pattern Optimization Algorithm For Effective Estimation Of Optimum Particle Initial Values, Yongbin Chou, Shuchun Zhang, Yuancheng Wang, Wenlan Fan, Dexin Li Jan 2019

Linear Array Pattern Optimization Algorithm For Effective Estimation Of Optimum Particle Initial Values, Yongbin Chou, Shuchun Zhang, Yuancheng Wang, Wenlan Fan, Dexin Li

Journal of System Simulation

Abstract: For particle swarm optimization (PSO), all particles are always initialized randomly, but here a new initialization method is presented to improve PSO optimizer convergence performance. On the basis of desired pattern, the corresponding aperture weights are solved by analytical techniques which can to a great extent ensure that these weights are effective estimations of the current optimum particle initial values. Then they are assigned to a particle as initial values, but all other particles of the swarm are still initialized randomly. Except this new initialization step, nothing is changed in PSO optimizer. The simulation results prove that this new …


Neural Coding Model For Fast And Significant Perceptual In The Pigeon Optic Tectum, Songwei Wang, Shuman Huang, Shi Li, Mengke Wang Jan 2019

Neural Coding Model For Fast And Significant Perceptual In The Pigeon Optic Tectum, Songwei Wang, Shuman Huang, Shi Li, Mengke Wang

Journal of System Simulation

Abstract: In the classical target recognition theory, many neurons in the mammalian retina and LGN perform DoG operations. Their functions are generally considered to be whitening, eliminating redundancy, and enhancing edges. Where is the redundant information? In this paper, the electrophysiological study of the ON-OFF neurons of the dove optic roof was performed. It was found that the FSL was used to carry out the rough and fast transfer of the whole scene information, and then the salient features in the scene were successively transmitted using the issue rate. For this reason, by analyzing the response pattern of neurons, this …


Research On Evaluation Framework Of Coa Based On Wargaming, Haiyang Liu, Yubo Tang, Xiaofeng Hu, Guangpeng Qiao Jan 2019

Research On Evaluation Framework Of Coa Based On Wargaming, Haiyang Liu, Yubo Tang, Xiaofeng Hu, Guangpeng Qiao

Journal of System Simulation

Abstract: Aiming at the evaluation problem of COA (course of action) level indicators in joint operation, an evaluation framework of COA based on wargaming was proposed. By multidimensional analysis of wargaming data, an evaluation feature space was constructed from basic features generated by data cube models and SoS (system of systems) features based on complex network. Wargaming experiments were used to generate small batch metrics results of COA level indicators, and the corresponding result labels of evaluation feature space data were generated by data fitting method. Two-phase correlation analysis was used for dimensionality reduction of high dimensional evaluation features. …


Improved Hybrid Devs-Based Equipment Modeling Method, Jianchun Zhang, Yanyang Zeng, Wenpeng Xu, Fengju Kang Jan 2019

Improved Hybrid Devs-Based Equipment Modeling Method, Jianchun Zhang, Yanyang Zeng, Wenpeng Xu, Fengju Kang

Journal of System Simulation

Abstract: Aiming at the shortcoming of model reuse and extensibility in the existing underwater warfare simulations, a hybrid modeling method based on improved hybrid DEVS (IHDEVS) is proposed. By analyzing the characteristics of combat in the underwater warfare, the event driven engagement process is constructed. From the two dimensions of entity function and behavior abstraction, a model classification strategy based on separation of concerns is designed, and a universal entity model framework is built based on the IHDEVS modeling theory, including layers of the interaction architecture, the coupling model and the atomic model. A typical example shows that this …


Numerical Simulation And Experimental Study On The Rolling Process Of Polar Particles, Yanjun Xiao, Kong Xuan, Wang Zhao, Zonghua Zhang, Yanchun Xiao Jan 2019

Numerical Simulation And Experimental Study On The Rolling Process Of Polar Particles, Yanjun Xiao, Kong Xuan, Wang Zhao, Zonghua Zhang, Yanchun Xiao

Journal of System Simulation

Abstract: The densification process of electrical paste particles during the process of battery pole piece rolling is studied. The mechanism of the pole rolling is analyzed theoretical;the basic parameters of the electric slurry particles in the movement are described; the force equation is established; and the basic conditions for the stable rolling are analyzed. The dynamic simulation is carried out by using relevant parameters, and the results are verified by theoretical analysis, numerical simulation and experimental verification. The results show that there is a certain relationship between the relative density of the electrode paste and the thickness of the …


Target Decision In Collaborative Air Combats Using Multi-Agent Particle Swarm Optimization, Yuewen Fu, Yuancheng Wang, Chen Zhen, Wenlan Fan Jan 2019

Target Decision In Collaborative Air Combats Using Multi-Agent Particle Swarm Optimization, Yuewen Fu, Yuancheng Wang, Chen Zhen, Wenlan Fan

Journal of System Simulation

Abstract: Under the research background of collaborative multi-aircraft and multi-target air combats, combined with the actual combat constraint conditions and the threat assessment functions on both sides, a collaborative air combat target decision simulation model is established for complex and changeable battlefield situations, which can reflect the priority of fire attack. To solve the decision scheme quickly and accurately, an improved multi-agent particle swarm optimization algorithm is proposed by introducing the interaction mechanism of the multi-agent theory into particle swarm optimization algorithm; and the neighborhood cooperation operator, mutation operator and self-learning operator for the agent are designed respectively. …


Ray-Casting Algorithm Based On Adaptive Compound Interpolation, Yanyang Zeng, Qingqing Pei, Baokun Li Jan 2019

Ray-Casting Algorithm Based On Adaptive Compound Interpolation, Yanyang Zeng, Qingqing Pei, Baokun Li

Journal of System Simulation

Abstract: The ray casting algorithm is widely used in volume rendering technology due to its mature algorithm and high imaging quality. To solve the problems of large amount of calculation and long rendering time caused by high-quality images, the problems of re-sampling point interpolation and time-consuming synthesis in the volume rendering process based on the traditional ray casting algorithm are studied, and an improved adaptive compound interpolation ray casting algorithm is proposed. According to the set threshold range, the size of the retreating sampling step is adjusted to select the interpolation sampling point and interpolation algorithm, and the re-sampling and …


Application Of Virtual Trial Makeup Based On Video, Jiayuan Liu, Jinfang Li, Hanwu He Jan 2019

Application Of Virtual Trial Makeup Based On Video, Jiayuan Liu, Jinfang Li, Hanwu He

Journal of System Simulation

Abstract: To try different cosmetic products in a convenient and low cost way, a virtual make-up algorithm based on a plane mesh model is proposed. The feature points are extracted from the face in the video by the Harr cascade classifier and the Dlib library. A mask pattern is built on the different parts of the face dynamically according to the texture coordinates of the plane mesh model. Theory is used to control the display area of the main texture of the planar mesh model. The mapping relationship between the main texture and the feature point coordinates of the planar …


Forward Algorithm Of Lwd Azimuthal Gamma, Qifeng Sun, Youxiang Duan, Yanan Yan, Hongqiang Li Jan 2019

Forward Algorithm Of Lwd Azimuthal Gamma, Qifeng Sun, Youxiang Duan, Yanan Yan, Hongqiang Li

Journal of System Simulation

Abstract: The study of the LWD (Logging While Drilling) azimuthal gamma imaging mode under different geological structures can provide bases for fast and accurate identification of drilled formation. The detection model of LWD azimuthal gamma is set up, and physical models of several positions of the formation and gamma detector is established, combining the descartes coordinate with the spherical coordinate, an azimuthal gamma log response algorithm under different position models is derived. Comparing the simulated results with the measured results of the azimuthal gamma ray logging tool, it is proved that the algorithm can effectively simulate the response characteristics of …


Visual Object Tracking Algorithm Based On Deep Denoising Autoencoder Over Rgb-D Data, Mingxin Jiang, Zhigeng Pan, Lanfang Wang, Taoxin Hu Jan 2019

Visual Object Tracking Algorithm Based On Deep Denoising Autoencoder Over Rgb-D Data, Mingxin Jiang, Zhigeng Pan, Lanfang Wang, Taoxin Hu

Journal of System Simulation

Abstract: A visual object tracking algorithm based on cross-modality features deep learning over RGB-D data is proposed. A sparse denoising autoencoder deep learning network is constructed, which can extract cross-modal features of the samples in RGB-D video data. The cross-modal features of the samples are input to the logistic regression classifier, the observation likelihood model is established according to the confidence score of the classifier, and the reasonable state transition model is established. The object tracking results over RGB-D data are obtained using particle filtering algorithm. Experimental results show that the proposed method has strong robustness to abnormal changes. …


Permanent Magnet Synchronous Motor Multi-Parameter Identification Based On Improved Salp Swarm Algorithm, Mengqiu Wang, Wang Yan, Zhicheng Ji Jan 2019

Permanent Magnet Synchronous Motor Multi-Parameter Identification Based On Improved Salp Swarm Algorithm, Mengqiu Wang, Wang Yan, Zhicheng Ji

Journal of System Simulation

Abstract: Since the multi-parameter identification of permanent magnet synchronous motor (PMSM) has slow speed and low accuracy, a parameter identification method based on the improved salp swarm algorithm was proposed in this paper. The algorithm firstly adopted the self-adaptive evaluation-move strategy and neighborhood optimum guide strategy based Von Neumann topology to update the position of followers twice, which strengthened information cooperation in the population and accelerated the convergence rate of parameter identification. Secondly, the algorithm used the opposition-based learning strategy to perturb the population position with a certain mutation probability, that avoided local optimum and misconvergence of the parameters. The …


Bayesian Evaluation Method For Energy Efficiency Of Manufacturing System Based On Combined Weights, Dongfeng Cao, Wang Yan Jan 2019

Bayesian Evaluation Method For Energy Efficiency Of Manufacturing System Based On Combined Weights, Dongfeng Cao, Wang Yan

Journal of System Simulation

Abstract: The energy consumption of discrete manufacturing system presents many complex characteristics such as multi-source, multi-level and dynamic uncertainty, which make energy efficiency analysis and evaluation very difficult. The evaluation index system of energy efficiency of discrete manufacturing system is constructed from three aspects: manufacturing equipment, processing tasks and products. The improved Bayesian probability evaluation model is adopted for energy efficiency evaluation. In determining the weight link, the dynamic modified AHM method is combined with entropy weight method to make up the uncertainty of the structure and parameters of the Bayesian model, and to synthesize the subjective and objective two …


Designing A Self-Adaptive Fuzzy Pid Controller For Aircraft Cabin Temperature, Zongshuai Li, Sibo Zhang Jan 2019

Designing A Self-Adaptive Fuzzy Pid Controller For Aircraft Cabin Temperature, Zongshuai Li, Sibo Zhang

Journal of System Simulation

Abstract: The temperature control system is a highly nonlinear and uncertainty system, and using a conventional PID controller makes it difficult to achieve a good control effect. In this paper, a self-adaptive fuzzy PID controller is described. The model of controlled object is established by combining mechanism modeling with experiment. Aiming at the problem that the parameter range of the self-adaptive fuzzy PID controller varies greatly and is difficult to adjust, a new method is proposed which can easily provide a more reasonable fuzzy controller output variable range. The fuzzy rules based on experts’ experience and knowledge are adopted. The …


Target Tracking Simulation For Unmarked Augmented Reality System Based On Kcf, Zhili Zhang, Wang Chao, Long Yong, Shaodi Wang Jan 2019

Target Tracking Simulation For Unmarked Augmented Reality System Based On Kcf, Zhili Zhang, Wang Chao, Long Yong, Shaodi Wang

Journal of System Simulation

Abstract: An AR system based on the kernelized correlation filter (KCF) target tracking is designed for solving the problem of the insufficiency of tracking in the unmarked augmented reality (AR). The KCF is used to identify and track the targets. The relevant parameters of the camera position are imported. The openGL graphical program interface is called to load the precast object onto the target. The KCF simulation experiment is carried out to track the target with visual studio. The results show that the AR application system based on KCF method can effectively improve the real-time performance of target tracking, and …


Improved Intrusion Weed Algorithm For Solving Flexible Job Shop Scheduling Problem, Zhang Xin, Li Ke, Dahu Yan, Zhicheng Ji Jan 2019

Improved Intrusion Weed Algorithm For Solving Flexible Job Shop Scheduling Problem, Zhang Xin, Li Ke, Dahu Yan, Zhicheng Ji

Journal of System Simulation

Abstract: An improved invasive weed optimization algorithm is proposed for solving multi-objective flexible job shop scheduling problem (FJSP) with released time and delivery date. The minimum completion time of jobs, the maximum work load of machines and the total work load of all machines are taken as the optimization goals to establish a FJSP model. A random key encoding scheme based on transformed sequences is proposed and a mapping relationship is set up between the continuous space and the discrete space of FJSP. An adaptive Gauss mutation operator is introduced to diversify the population in the process of weed breeding. …


Motif-Based Intelligent Mission Planning Method For Uav Swarms, Weiping Wang, Wang Tao, Xiaobo Li, Jiajie Liu Jan 2019

Motif-Based Intelligent Mission Planning Method For Uav Swarms, Weiping Wang, Wang Tao, Xiaobo Li, Jiajie Liu

Journal of System Simulation

Abstract: Due to the restriction of communication among UAV swarms, configuration of UAV swarms needs to be changed dynamically along with the task changes. How to do mission planning under limited communication for UAV swarms has become a hot and difficult question. The UAV combat network motif model framework is built based on the function, and six different types of basic motif model are proposed. Through capability demand and communication demand, a task is mapped into types and numbers of motifs which are required to complete the task. The ‘multidimensional dynamic scheduling list’ method is used to automatically generate mission …


Group Consensus Of Multi-Agent Networks With Multiple Time Delays, Lianghao Ji, Xinyue Zhao Jan 2019

Group Consensus Of Multi-Agent Networks With Multiple Time Delays, Lianghao Ji, Xinyue Zhao

Journal of System Simulation

Abstract: The group consensus problems for first-order and second-order multi-agent networks with multiple time delays are investigated respectively. Based on the theory of frequency-domain, some algebraic criteria are analytically proposed, which can guarantee the achievement of group consensus. The results show that the input time delays, the coupling weights and the coupling strengths between the agents play key roles in reaching group consensus, whereas communication time delays can only affect the convergence rate of the systems. The validity of the results is verified by several simulated examples.


Modeling And Simulation On Delay Of Central Heating System For Temperature Prediction, Sun Tao, Shaoxiong Ji Jan 2019

Modeling And Simulation On Delay Of Central Heating System For Temperature Prediction, Sun Tao, Shaoxiong Ji

Journal of System Simulation

Abstract: Heating prediction is essential for energy saving. However, it is difficult to some extent because the central heating system (CHS) is nonlinear with large-scaled delay and other characteristics. Based on physical laws of the CHS, a novel model combining pruning algorithm with the least mean square is proposed to solve the problem of delay and predict the temperature. The model with the delay taking into consideration conforms to the law of thermal transmission. The pruning algorithm lowers the computational complexity. Simulations using gradient descent least squared regression (LSR), support vector machine (SVM), least-squared support vector machine (LS-SVM) …


Flow Field Analysis Of Pipeline Pig Receiving Trap, Chuanjun Han, Yu Cheng, Xingzhi Duan, Li Qi Jan 2019

Flow Field Analysis Of Pipeline Pig Receiving Trap, Chuanjun Han, Yu Cheng, Xingzhi Duan, Li Qi

Journal of System Simulation

Abstract: To study the influence of piping diameter on the flow field characteristics when pig receiving trap is working, the finite element model of pig receiving trap whose type is P6.3MPa DN700/DN600 was established, and the effects of the diameters changes of vent pipe and blow-off pipe were simulated. The effects caused by the pig running speeds on the flow field of the pig receiving trap were studied. The results show that in the pig receiving trap, there is the maximum pressure in the left side of pig staying and the pressure begins to decrease and easy to form swirls …


Risk Analysis Of Semitrailer Overtaking On Curved Sections Based On Dynamic Simulation, Zhang Chi, Qi Chen, Xiaomin Yan, Dongjian Shao, Zhang Min Jan 2019

Risk Analysis Of Semitrailer Overtaking On Curved Sections Based On Dynamic Simulation, Zhang Chi, Qi Chen, Xiaomin Yan, Dongjian Shao, Zhang Min

Journal of System Simulation

Abstract: To study the safety of semitrailers corner overtaking behavior, the dynamic model of vehicle, the road model and the drivers' aiming trajectory model were developed by multi-body dynamics simulation software TruckSim. The semitrailers were simulated in separate working conditions by changing the super-elevations, circular curve radius, vehicle turning radius and speed. Lateral load transfer rate was invoked as the evaluation index for evaluating the vehicle's safety. The model of six axle semitrailer side tumbling stability prediction was established through the Spss regression; the risk of overtaking on five separate bends of a western highway was evaluated by the model. …


L2-Gain Robust Control For Flexible Joints And Flexible Link Space Robot, Lijiao Zhang, Chen Li Jan 2019

L2-Gain Robust Control For Flexible Joints And Flexible Link Space Robot, Lijiao Zhang, Chen Li

Journal of System Simulation

Abstract: The trajectory tracking and the double flexible vibration active suppression control for free-floating space robot with flexible-joints and flexible-link were proposed. The dynamic equation of the system was established according to system’s momentum conservation and Lagrange method. A singular perturbation model was established by integral manifold method, and the system was decomposed into a fast subsystem of flexible-joint which used the speed difference between the feedbacks of control law to suppress the elastic vibration of flexible-joints, a fast subsystemof flexible-link which designed optimal linear quadratic regulator (LQR) to damp out the vibration of the flexible manipulator and …


Improved Bp Neural Network Of Heat Load Forecasting Based On Temperature And Date Type, Li Qi, Zhao Feng Jan 2019

Improved Bp Neural Network Of Heat Load Forecasting Based On Temperature And Date Type, Li Qi, Zhao Feng

Journal of System Simulation

Abstract: The heat load forecasting provides data support for urban district heating systems, which is the basis of need-based heating. The change of heat load is greatly influenced by various exterior factors, especially the outdoor temperature. To meet demand of heating system, save energy and balance the comfort of human body, a kind of improved BP neural network method is proposed by temperature and date type. The temperature and date type are quantified and the heat load forecasting model is established by using BP neural network. To guarantee prediction accuracy, the genetic algorithm is used to optimize the weights and …


Application Of Multiple-Stepwise And Kalman Filtering In Haze Forecast, Yunhao Xian, Hengde Zhang, Yonghua Xie, Le Yang Jan 2019

Application Of Multiple-Stepwise And Kalman Filtering In Haze Forecast, Yunhao Xian, Hengde Zhang, Yonghua Xie, Le Yang

Journal of System Simulation

Abstract: Considering the importance of objective haze forecast and the low accuracy rate of haze forecast, a new haze objective forecast correction method based on the multiple stepwise regression algorithms and the Kalman filtering algorithm is proposed. The multiple stepwise regression method is used to control the physical factor of the dependent variable, and the visibility forecast equation is established. The Kalman filtering method is adopted to correct the regression coefficient in multivariate stepwise regression algorithm according to the actual data, and the haze objective forecast correction model is established. The experiments are carried out in Beijing, Guangzhou, Nanjing and …


Finite Element Analysis Of Magnetic Flux Leakage Detection For Transverse Cracks Of Sucker Rod, Zhang Ou, Xueye Wei, Wang Pei, Shuxin Yan Jan 2019

Finite Element Analysis Of Magnetic Flux Leakage Detection For Transverse Cracks Of Sucker Rod, Zhang Ou, Xueye Wei, Wang Pei, Shuxin Yan

Journal of System Simulation

Abstract: The modeling and testing technology of the surface transverse cracks of complex defecting for sucker rod were studied, and a finite element simulation model of rod transverse defects was built. The magnetic flux leakage testing simulation was carried out by using ANSYS software, and the changing trend between the lift-off value and the leakage magnetic field was obtained. Two kinds of different magnetization modes of single coil and double coils were analyzed, and the result showed that the double coils magnetization is superior to single coil magnetization. The two dimensional and three dimensional magnetic flux leakage testing …


Design Of Third-Order Zero-Free Mracs Taking State Variables From Model, Qian Chao, Song Fei Jan 2019

Design Of Third-Order Zero-Free Mracs Taking State Variables From Model, Qian Chao, Song Fei

Journal of System Simulation

Abstract: Since the current design method of the relative order n*≥3 MRACS taking state variables from model introduces some linear positive feedback loops, so it is difficult to be used in practical systems. This paper took the third-order zero-free (n*=3) system as the study object and designed the controller for third-order zero-free MRACS taking state variables from model by using the zero state equivalence relation between two different control systems. The design method of the controller is based on the Popov hyperstability theory. The controller only used integrators except for a differentiator and avoided introducing linear …


Sliding Backstepping Mode Control For Flight Simulator Servo Based On Disturbance Compensation And Differentiator, Huibo Liu, Shanglei Liu Jan 2019

Sliding Backstepping Mode Control For Flight Simulator Servo Based On Disturbance Compensation And Differentiator, Huibo Liu, Shanglei Liu

Journal of System Simulation

Abstract: Considering the uncertain factors in flight simulator servo system, such as friction torque and modeling error, a sliding backstepping mode control strategy based on the nonlinear extended state observer (NESO) and differentiator was put forward. The uncertain factors were defined as compound disturbances, and the NESO was used for observations in combination with real-time compensations that reduced impact on the system brought by disturbances. Differentiator was used to estimate the system state variables, hence preventing the noise amplifications caused by the difference method; law design came under the control of a sliding backstepping mode controller designed in accordance with …


Dynamic Data Modeling Driven Model For Forest Fire Spread Based On Devs, Guoxiong Zhou, Kejia Yin, Aibin Chen Jan 2019

Dynamic Data Modeling Driven Model For Forest Fire Spread Based On Devs, Guoxiong Zhou, Kejia Yin, Aibin Chen

Journal of System Simulation

Abstract: According to the characteristics of fire behavior with strong sudden, disposal of difficult rescue, and heavy destructiveness, combining dynamic data system and discrete event system specification model, a dynamic data driven forest fire spread model is put forward based on devs modeling. The dynamic data system needs to be realized through the interaction between the computer software and the data characteristics of each environment, which is characterized by flexible data and real data. DEVS supports object-oriented modeling, and can make the modeling and simulation of the system modular, hierarchical and formal. The model is set up according to the …


Multi-Constraint Service Selection Based On Decomposition Of Global Qos, Fang Chen, Jindong Wang, Hengwei Zhang, Wang Na Jan 2019

Multi-Constraint Service Selection Based On Decomposition Of Global Qos, Fang Chen, Jindong Wang, Hengwei Zhang, Wang Na

Journal of System Simulation

Abstract: With the rapid growth of Web services in cloud computing environment, users make new demands on dynamic service composition, that quickly selects composite service which can meet multi-constraints. According to the demand, a multi-constraint service selection method based on decomposition of global QoS was proposed. A new cultural genetic algorithm was designed to decompose the global QoS constraints, and services were filtered by combining with the functional constraints between candidate services. An adaptive replacement strategy was used to dynamically adjust QoS constraint boundaries, so as to ensure the most appropriate composite service obtained by local selection. Experimental results show …


Abnormal Event Driven Rescheduling Decision Making In Discrete Manufacturing Workshop, Weixi Ji, Youyong Cai, Chaoyang Zhang, Peng Wei Jan 2019

Abnormal Event Driven Rescheduling Decision Making In Discrete Manufacturing Workshop, Weixi Ji, Youyong Cai, Chaoyang Zhang, Peng Wei

Journal of System Simulation

Abstract: To solve the problem of rescheduling of workshop production process, combined with the present situation of transparent manufacturing process in discrete workshop, a decision method of rescheduling and an event processing in discrete workshop driven by the abnormal events are proposed. In the IOT driven discrete manufacturing workshop environment, the complex event processing technology is applied to analyze and deal with the real-time information on manufacturing processes. On this basis, by defining the driven mechanism, the decision scheme and the performance evaluation index of rescheduling, the decision method of rescheduling in discrete workshop facing the costing is put forward; …


Modeling And Research Of Global Allocation Policy In Cascading Failures, Chongjie Dong Jan 2019

Modeling And Research Of Global Allocation Policy In Cascading Failures, Chongjie Dong

Journal of System Simulation

Abstract: In reality, the global loads of network usually alter when the structure and function of network change by a list of attacks. Based on this, the paper defines extra loads of the normal node inversely proportional to the distance of failure node and presents a new indicator named "diffusion step" to failure diffusion process, which uses the global allocation policy instead of neighbor or local feature of node. By simulating scale-free network, small-world network and random network, the average results of network show that the scale-free network has strong ability to resist failures. When the influence of global allocation …