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Optimizing Control Of Total Heat Supply Based On Machine Learning, Li Qi, Xingqi Hu, Jianmin Zhao Jan 2019

Optimizing Control Of Total Heat Supply Based On Machine Learning, Li Qi, Xingqi Hu, Jianmin Zhao

Journal of System Simulation

Abstract: The central heating system has complex structure, along with the characteristics of hysteresis, strong coupling and nonlinear. Contraposing the problem that the process is difficult to be identified and controlled by the mechanism modeling, an optimal control method of heat source total heat production based on machine learning is proposed. The heat source model of central heating system is established by BP neural network and long short-term memory neural network. Under the premise of meeting the demand of heating quality, with the total energy consumption as the optimization objective, the optimal control sequence of water supply temperature and water …


Integrated Berth And Quay Crane Allocation Multi-Objective Algorithm For Container Terminal, Wang Xu, Shixin Liu, Ruiyou Zhang, Wang Jia Jan 2019

Integrated Berth And Quay Crane Allocation Multi-Objective Algorithm For Container Terminal, Wang Xu, Shixin Liu, Ruiyou Zhang, Wang Jia

Journal of System Simulation

Abstract: This paper researches on a continuous berth and quay crane allocation problem for low carbon container terminal. Considering the constraints of stochastic arrival time and limited truck transportation ability, a multi-objective nonlinear mixed integer programming model is established to minimize carbon emissions and average delay time. An efficient non-dominate sorting genetic algorithm II (ENSGA-II) is designed to deal with this problem. According to the characteristics of the problem, encoding rule and decoding rule based on rolling-horizon simulation, PPX crossover operator with elite selection, multi constraints mutation operator and repair operator are adopted. The results of several simulation experiments …


Route Planning For Vessel Based On Dynamic Complexity Map, Zhe Du, Yuanqiao Wen, Huang Liang, Chunhui Zhou, Changshi Xiao Jun 2018

Route Planning For Vessel Based On Dynamic Complexity Map, Zhe Du, Yuanqiao Wen, Huang Liang, Chunhui Zhou, Changshi Xiao

Journal of System Simulation

Abstract: Aiming at multiple mobile objects in complex navigation environment, a route planning method based on the dynamic complexity map is proposed. According to the theory of complexity measurement, a dynamic complexity map is established. By taking advantage of the idea of A * algorithm, the complexity value is taken as an actual cost and the Euclidean Distance from current point to the target is taken as a heuristic costs. Considering the ship dimensions, the channel boundary constraint function is added. The experimental results show that on the premises of satisfying the constraint of ship dimensions, the planned route …


Synthesizing Rotational Human Motion With Physical Reality, Wei Yi, Shihong Xia Jun 2018

Synthesizing Rotational Human Motion With Physical Reality, Wei Yi, Shihong Xia

Journal of System Simulation

Abstract: Both keyframes and their timings play an important role in synthesizing physically realistic human motion. However, physically plausible timings are hard to set by manual. By combing keyframes and the physics-based optimization, a new method is proposed to solve physically plausible timings of given keyframes. Firstly, the keyframes and the initial value of the timings of keyframes are set through a graphical user interface. Secondly, the physically plausible timings of keyframes are obtained by optimizing a small-size nonlinear optimization model. Finally, the rotational human motion is synthesized by the keyframes and the computed timings of keyframes. Experiments are performed …


Performance Analysis And Research Of Shark Fin Structure Based On Simulation, Liu Shuang, Lü Chao, Rao Yong, Shiming Wang Jun 2018

Performance Analysis And Research Of Shark Fin Structure Based On Simulation, Liu Shuang, Lü Chao, Rao Yong, Shiming Wang

Journal of System Simulation

Abstract: The shark fin, the pectoral fin and the dorsal fin were studied based on the numerical simulation method; the pressure field, velocity field and flow field of the specimen structure were analyzed with three different flow velocities; the analysis and comparison of the mechanical properties of caudal fin, dorsal fin and pectoral fin were presented. The results show that the setting width of the tail fin can be set to 0.5 ~ 4.8 meters so as to improve the anti-karman vortex effect; the width of the tail fins should be relatively narrow in order to guarantee the base of …


Physically-Based Dynamic Algorithms For Time-Varying Of Flowers And Leaves, Jiao Di, Yang Meng, Yang Gang Jun 2018

Physically-Based Dynamic Algorithms For Time-Varying Of Flowers And Leaves, Jiao Di, Yang Meng, Yang Gang

Journal of System Simulation

Abstract: This paper presents physically-based simulations of dynamic algorithms of the blossom and fading of flowers as well as the time-varying leaves following the seasons. The models of the flowers are constructed according to the previously collected primary biological data of organs of flowers. The dynamic simulation is presented by two phases: the process of blooming and the process of fading. To simulate the former, the curved surfaces of petals are controlled by controlling the points on the Bezier surface; for realizing the simulation of the latter, the physical method is used. The dynamic effects of colors of leaves according …


Emergency Condition Selection Based On Tcp-Nets, Weihong Liu, Zheng Xiao, Cheng Chen, Li Qiao Jun 2018

Emergency Condition Selection Based On Tcp-Nets, Weihong Liu, Zheng Xiao, Cheng Chen, Li Qiao

Journal of System Simulation

Abstract: The representative or relative important emergency conditions need to be selected for making well-directed emergency plans. The quantitative method is normally used to select emergency conditions, but it requires users to specify the weight of every attribute, which does not conform to the users' habit. A qualitative method for emergency condition selection is put forward which includes two steps: for the first step, TCP-nets is adopted to describe users' requirements; and for the second step, the most important emergency conditions are selected based on TCP-nets. The effectiveness of the method is proved, and the efficiency is verified by experiments …


Key Technology Of Oil Spill Visualization At Sea Surface, Changjun Zou, Yin Yong, Xiuwen Liu, Feifei Wan Jun 2018

Key Technology Of Oil Spill Visualization At Sea Surface, Changjun Zou, Yin Yong, Xiuwen Liu, Feifei Wan

Journal of System Simulation

Abstract: An intensive study is made on the visualization method and oil equipment interaction. To solve the blind area problem and to realize the interactive of oil film, the following methods are proposed: new visualization method based on texture projection; modeling technique of oil boom based on mass-spring model; dynamic interaction method between oil boom and oil film texture based on polygon clipping. Real-time oil spill visualization at sea is implemented on GPU, the test results show the correctness and reliability of the methods.


Cooperative Target Recognition With Multiple Features Judgment, Guopeng Sun, Xiangyang Hao, Zhenjie Zhang, Pengrui Yan Jun 2018

Cooperative Target Recognition With Multiple Features Judgment, Guopeng Sun, Xiangyang Hao, Zhenjie Zhang, Pengrui Yan

Journal of System Simulation

Abstract: For solving cooperative target recognition problem in visual navigation, a fast and accurate algorithm based on progressive judgment of multiple features is proposed. The image is processed and judged by multiple features including image contours, Hu moment invariants and FAST corners. The non-target areas are eliminated and the real targets are obtained. In the process, algorithm is improved and some accelerated strategies are adopted to meet real-time requirements. Experiments show that the proposed algorithm can identify cooperative target robustly and adaptively with different distances, different angles and environment disturbance.


A Lightweight Modeling And Simulation Technical Framework For Complex Systems, Ji Hang, Junhua Zhou, Guoqiang Shi, Tingyu Lin, Junjie Xue Jun 2018

A Lightweight Modeling And Simulation Technical Framework For Complex Systems, Ji Hang, Junhua Zhou, Guoqiang Shi, Tingyu Lin, Junjie Xue

Journal of System Simulation

Abstract: Aiming at the modeling and simulation verification of complex systems, the paper established a lightweight simulation technical framework and a system building method. The simulation technical framework is built based on distributed network communication middleware and has graphic user interface, simulation management and run control modules, it packages effective and lightweight network middleware, object management, event management and time management and it is capable of interoperability and its members have abilities of reusable and combinable. The results show that the framework can supports flexible construction and effective simulation on complex systems.


Eye Gaze Tracking In 3d Immersive Environments, Xincan Zhao, Shihao Pan, Yaping Wang, Tie Yun Jun 2018

Eye Gaze Tracking In 3d Immersive Environments, Xincan Zhao, Shihao Pan, Yaping Wang, Tie Yun

Journal of System Simulation

Abstract: Aiming at the problem that human-computer interaction in immersive environments is entirely dependent on the body movement with low operational efficiency,a 3D eye gaze tracking method is proposed to gain the 3D gaze point of the user. Thus the interactive operation could be achieved, which provides a natural and bidirectional way for interaction. The Leap Motion controller is innovatively used to track the coordinates of eyes and the head position is tracked with the motion capture device. The gaze point under free movement can be estimated based on the mapping equation that is obtained in the initial …


Batik Dying Simulation Based On Diffusion, Yangtao Yu, Zhenlu Yu, Wenhua Qian, Keshi Zhang, Xu Dan Jun 2018

Batik Dying Simulation Based On Diffusion, Yangtao Yu, Zhenlu Yu, Wenhua Qian, Keshi Zhang, Xu Dan

Journal of System Simulation

Abstract: This paper presents a three-layer model which is composed of wax layer, warp layer and weft layer. The wax layer wraps warp and weft layer which overlap together. According to Fick's second law and considering dye's diffusion, absorption and supply, a differential equation is built to describe diffusion process and this equation is discretized. Porosity, tortuosity and neighboring coefficient are used in the equation. Rectangular weave is simulated by using ellipse-distance model and blurred in HSV color space. Simulation shows that the satisfactory visual effect which closes to real batik cloth is acquired by the method and the algorithm …


Temperature Characteristics Of Contact Wire Under Different Driving Intervals, Hongwei Wang, Zhang Kai, Zhiyong Wang, Fengyi Guo, Liu Shuai, Zhang Qiong Jun 2018

Temperature Characteristics Of Contact Wire Under Different Driving Intervals, Hongwei Wang, Zhang Kai, Zhiyong Wang, Fengyi Guo, Liu Shuai, Zhang Qiong

Journal of System Simulation

Abstract: To reduce the wear of pantograph and catenary system while decreasing the headway, the temperature field of the contact wire is studied. A simulation model is established by using the COMSOL Multiphysics software. The effectiveness of the model is verified with temperature experiments. Temperature field of the contact wire of freight locomotive and passenger locomotive in different intervals is studied by simulation. The smaller the headway of trains, the higher the temperature value, and the shorter the balance process. Under the constraint of temperature field, the headway of freight locomotive couldn't be less than 180s under long term operation. …


Space Communication Network Cascading Failure Model Oriented System Combat, Zhu Lin, Shengliang Fang, Jinsong Wang, Fuxiang Wu Jun 2018

Space Communication Network Cascading Failure Model Oriented System Combat, Zhu Lin, Shengliang Fang, Jinsong Wang, Fuxiang Wu

Journal of System Simulation

Abstract: According to the structure characteristics of space communication network, a node attack model for space communication network was designed. A space communication network cascading failure model was proposed by analyzing the assigning of initial load and the capacity of node, the judging regulation of node cascading and the reassigning algorithm of node load. The evaluation method of network robustness based on the loss ratio of operation loop was put forward. The validity of the model is illustrated by a case of combat system network cascading failure process. The simulation results also revealed the relationship between the cascading failures results …


Equipment Rul Prediction Oriented Parallel Simulation Framework, Chenglong Ge, Yuanchang Zhu, Yanqiang Di, Zhiwei Hu, Zhihua Dong Jun 2018

Equipment Rul Prediction Oriented Parallel Simulation Framework, Chenglong Ge, Yuanchang Zhu, Yanqiang Di, Zhiwei Hu, Zhihua Dong

Journal of System Simulation

Abstract: As the equipment states are complicated with uncertainty, predicting remaining useful life with self-updating ability has become a hard task. Simulation provides an effective way to solve the problem. The concept and technology framework of equipment remaining useful life prediction oriented parallel simulation are proposed based on parallel system theory and the concept, characteristics, capacity demands and functional compositions of parallel simulation are introduced. The main modeling technologies of equipment remaining useful life prediction oriented parallel simulation are discussed, which include awareness of equipment degradation state, construction of equipment degradation state space model and evolution of equipment degradation state …


3d Visual Effects Assessment Based On Comprehensive Weight, Yanyang Zeng, Zhenjing Feng Jun 2018

3d Visual Effects Assessment Based On Comprehensive Weight, Yanyang Zeng, Zhenjing Feng

Journal of System Simulation

Abstract: There are various indicators for assessing the 3D visual effects, while the general weight of each index needs pre-determined coefficients individually, for which either the expert knowledge model or theoretical model used has advantages and disadvantages empowerment. Based on expert knowledge and theoretical models, the comprehensive weight method, optimization model, and direct solution of the index weight vectors have subjective and objective information. Experimental results show that the method of determining the weight vector different sort results of the assessment is also slightly different. Integrated weighting method to determine the weight of each index and the corresponding results of …


Algorithm For Tracking Position And Orientation Of Drug Delivery Capsules In Gastrointestinal Tract, Xudong Guo, Zhengping Lu, Qinfen Jiang, Shuyi Wang, Haipo Cui Jun 2018

Algorithm For Tracking Position And Orientation Of Drug Delivery Capsules In Gastrointestinal Tract, Xudong Guo, Zhengping Lu, Qinfen Jiang, Shuyi Wang, Haipo Cui

Journal of System Simulation

Abstract: To realize an accurate releasing by a drug-delivery capsule in the gastrointestinal tract, a method of magnetic vector detection with angle sensing has been presented to track the capsule in real time; and a prototype of the tracking system has been developed. Based on the fundamentals of spatial distribution of magnetic vector fields, a nonlinear model of tracking is established. An improved artificial bee colony algorithm is studied to solve the magnetic inverse problem. In the improved algorithm, a chaos operator is used to generate an initial population and a sort selection is used to prevent premature convergence. …


Event-Triggered Non-Fragile H State Estimation For Fuzzy Time-Delay Neural Networks, Yanqin Wang, Weijian Ren Jun 2018

Event-Triggered Non-Fragile H∞ State Estimation For Fuzzy Time-Delay Neural Networks, Yanqin Wang, Weijian Ren

Journal of System Simulation

Abstract: For a class of fuzzy neural networks with randomly occurring time-varying delays and randomly data packet loss, an event-triggered non-fragile H state estimator is designed. The event-triggered condition is introduced to determine whether the signal is transmitted or not, so as to reduce the occupation rate of network resource. Random variables of Gaussian distribution and the multiplicative gain uncertainties are adopted to construct the non-fragile state estimator with randomly occurring gain variations. By constructing Lyapunov function, and via stochastic computation and linear matrix inequality technique, the sufficient conditions for the existence of non-fragile estimators are obtained, which guarantee …


Svm Prediction Of Performance Degradation Of Rolling Bearings With Fusion Of Kpca And Information Granulation, Jiya Xu, Wang Yan, Dahu Yan, Zhicheng Ji Jun 2018

Svm Prediction Of Performance Degradation Of Rolling Bearings With Fusion Of Kpca And Information Granulation, Jiya Xu, Wang Yan, Dahu Yan, Zhicheng Ji

Journal of System Simulation

Abstract: To effectively predict the performance degradation index and its fluctuation ranges of the rolling bearing, a prediction method based on kernel principal component analysis algorithm and fuzzy information granulation using support vector machine is proposed. The kernel principal component analysis is utilized to preprocess the data to acquire the main feature vector, construct T2 and SPE statistics, and to analyze its trend. The statistical information is used as the performance degradation index. Theory of fuzzy information granulation is used to granulate the performance degradation index and extract the useful information. The granulated data are put to the support …


Research On Maturity Evaluation Technology Of Complex Digital Industrial System, Geng Chao, Shiyou Qu, Tingyu Lin, Guoqiang Shi, Yingying Xiao, Wang Mei, Qiudan Ma, Ji Hang Jun 2018

Research On Maturity Evaluation Technology Of Complex Digital Industrial System, Geng Chao, Shiyou Qu, Tingyu Lin, Guoqiang Shi, Yingying Xiao, Wang Mei, Qiudan Ma, Ji Hang

Journal of System Simulation

Abstract: Under the background of a new round of the innovation of science and technology and the revolution of industry, the complex digital industrial system is constantly innovating and shaping. Firstly, the paper established maturity evaluation model of the complex digital industrial system based on system engineering. Then, the paper proposed multi - index maturity analysis method and multi - enterprise maturity synthesis method of the complex digital industrial system. Combined with the digital industrial system of aerospace complex product, an evaluation example is presented. The results show that the maturity evaluation method can be used to standardize and guide …


Channel Capacity Analysis Of Diffusion-Based Molecular Communication Model, Cheng Zhen, Lin Fei, Yanjing Lei, Huiting Zhao Jun 2018

Channel Capacity Analysis Of Diffusion-Based Molecular Communication Model, Cheng Zhen, Lin Fei, Yanjing Lei, Huiting Zhao

Journal of System Simulation

Abstract: At present, the research on the channel capacity of diffusion-based molecular communication (DBMC) model is very limited. In the slotted point to point communication scenario, considering all the inter-symbol interferences from all the previous time slots, the optimal decisive threshold is provided by using the criterion of minimum average error probability in the detection process for the receiver nanomachine, and the mutual information expression is derived in DBMC model. Thus channel capacity of this model is analyzed. The simulation results show that the different parameters have important influences on the channel capacity. Compared to the existed point to point …


Simulation Of Hot Event Propagation Based On Game Theory And Sirs, Dezhi Wei, Fuji Chen, Lina Lin Jun 2018

Simulation Of Hot Event Propagation Based On Game Theory And Sirs, Dezhi Wei, Fuji Chen, Lina Lin

Journal of System Simulation

Abstract: The hot events of the internet public opinion spread fast and have great influence. It has become a topic of concern for netizens and governments. The spread of hot spots on the internet is similar to the dynamics of infectious diseases, so a traditional SIRS epidemic model based improved model is proposed, combining the analysis of the game theory. The evolutionary game model of infectious body and immune body is constructed, the equilibrium point of the game is found and the law of the spread of hot spots is obtained. The model is verified by experiment through the …


Identification Of Closed Loop Projection Subspace For Motor Based On Hankel Correlation Function, Minghong She Jun 2018

Identification Of Closed Loop Projection Subspace For Motor Based On Hankel Correlation Function, Minghong She

Journal of System Simulation

Abstract: To solve estimation deviation problem of model parameter in the closed-loop system identification, the subspace identification model and state space model based on the estimation of the correlation function are presented, and through the correlation function estimation and zero space followed by projection, the block Hankel matrix of identification framework was filled so as to obtain the scope of the extended observability matrix; on the basis of the same projection on the time offset set of related data, the RQ decomposition of the projection is calculated by numerical calculation, and the dynamic estimation of the system model is obtained. …


Combination Forecasting Of Stock Index Time Series Based On Cooperative Game Theory, Luo Wei Jun 2018

Combination Forecasting Of Stock Index Time Series Based On Cooperative Game Theory, Luo Wei

Journal of System Simulation

Abstract: In view of the characteristics of nonlinear, large amplitude, frequent fluctuations in China's stock market, a prediction method of intelligent composite stock index time series based on the cooperative game is presented. The prediction model of stock index time series is established by using neural network method based on the correlations among the various economic indicators, and the development trend and laws of stock index time series are established by using the improved ARIMA method. The two methods are combined by importing cooperative game method. Simulation results show that the prediction accuracy of the presented method is controlled …


Modeling And Computer Simulation Of Numerical Experiments On Laser Propagation Through Atmospheric Turbulence, Chunyi Chen, Huamin Yang, Bin Ren, Zhengang Jiang Jun 2018

Modeling And Computer Simulation Of Numerical Experiments On Laser Propagation Through Atmospheric Turbulence, Chunyi Chen, Huamin Yang, Bin Ren, Zhengang Jiang

Journal of System Simulation

Abstract: Focusing on numerical simulations of laser propagation in atmospheric turbulence, a method for determining the grid size of optical-field samples that need to be stored in a data file was first suggested, and a simulation scheme based on a parallel computer cluster was proposed. By performing simulation examples, both the average intensity of collimated fundamental Gaussian beams propagating through atmospheric turbulence and the change in spatial-mode composition of Laguerre-Gaussian (LG) beams travelling in atmospheric turbulence were studied. Analyses show that for the case of horizontal propagation, the use of a matching approach based on zero-order moment to determine …


Real-Time Simulator For Spatial Information Networks Based On Analog If Signal Processing, Zeguo Yang, Ma Shang, Diaopeng Huang, Jianhao Hu, Lixiang Liu Jun 2018

Real-Time Simulator For Spatial Information Networks Based On Analog If Signal Processing, Zeguo Yang, Ma Shang, Diaopeng Huang, Jianhao Hu, Lixiang Liu

Journal of System Simulation

Abstract: To solve the problem of real-time simulation of spatial information network with high dynamic network topology, a real-time simulator based on the IF signal processing is proposed. Compared with traditional channel simulator, it supports both the channel transmission characteristics like channel fading, Doppler shift, noise, and path delay, and the real-time simulation of dynamic network topology changes. The simulator supports 8~128 70 MHz IF (0~20 MHz signal bandwidth) emulated nodes with flexible link type configuration. The maximal fading depth is 100 dB, the maximal Doppler shift is 2 MHz, and the maximal path delay can reach up …


Matlab Simulation For Electrically Excited Synchronous Motors With Low Switching Frequency, Qingqing Yuan, Bin Song, Yang Na Jun 2018

Matlab Simulation For Electrically Excited Synchronous Motors With Low Switching Frequency, Qingqing Yuan, Bin Song, Yang Na

Journal of System Simulation

Abstract: Switch loss is one of the main energy consumption of the high power transmission system, while the low switching frequency approach is an effective way to improve above issues. However, it will result in a severe harmonic distortion and further affect the control performance. A selective harmonic elimination pulse width modulation (SHEPWM) strategy has been used to ensure the low energy consumption operation of a diode clamped three-level converter whose load is a high power electrically excited synchronous motors (EESM). For the SHEPWM's characteristics of specific harmonic elimination and harmonic energy moving on the high order, a simple high-pass …


Simulation Analysis Of Magnetic Field Effect In Induction Heating Coil Of Porous Silicon Core Furnace, Jingang Li, Gaoyuan Liu Jun 2018

Simulation Analysis Of Magnetic Field Effect In Induction Heating Coil Of Porous Silicon Core Furnace, Jingang Li, Gaoyuan Liu

Journal of System Simulation

Abstract: A new technology of porous coil disposable drawing a plurality of single crystal silicon rod can solve the problem of low efficiency and high cost of zone melting method of single induction heating coil in drawing monocrystalline silicon. However,the missing of the theoretical research and mature technology leads to different sizes of monocrystalline silicon rods. According to electromagnetic theory,Some characterisitics of the porous coil are studied,including magnetic field model,operating principle,magnetic field distribution.To prove the mechanism of the technology, a mathematical model of the porous coil is constructed based on Matlab and Ansys software. The magnetic flux density distribution …


Research And Simulation Of Roots-Type Power Machine Control System Based On Fuzzy Pid, Yan-Jun Xiao, Yonggeng Wang, Jing Ran, Feng Hua, Yongcong Li Jun 2018

Research And Simulation Of Roots-Type Power Machine Control System Based On Fuzzy Pid, Yan-Jun Xiao, Yonggeng Wang, Jing Ran, Feng Hua, Yongcong Li

Journal of System Simulation

Abstract: For utilizing the domestic low grade waste heat resources, a Roots-type steam engine is developed. To make the roots engine stably output electric energy, an efficient constant power control system needs to be designed. The controlled object characteristics of the roots engine are analyzed; the modeling of the control system is established; and on this basis the fuzzy control algorithm is introduced. The fuzzy adaptive PID controller for the roots power machine constant power output is designed and the related MATLAB simulation is carried out. The results show that the Roots type steam power machine with fuzzy adaptive PID …


Parallel Design And Load Balance Of Openmp Based Warfighting Simulation, Wang Xiao, Yaqi Liu, Yuben Tao Jun 2018

Parallel Design And Load Balance Of Openmp Based Warfighting Simulation, Wang Xiao, Yaqi Liu, Yuben Tao

Journal of System Simulation

Abstract: Parallel simulation is a main trend of large scale and high precision war fighting simulation (WS). However, currently there is no unified framework to design a parallel WS and no effective method to load balance of it. Based on the parallel agent theory, an OpenMP based parallel WS design framework (PWSF) is proposed. To solve the problem of the complex simulation load distribution resulted from the diversity of entities' models and the position independence of the interactions, a load balance method based on METIS multilevel graph partition tool is suggested. Based on the improved PHOLD test model, experiments on …