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Full-Text Articles in Physical Sciences and Mathematics

Design And Implementation Of Hardware-In-The-Loop Simulation Dynamic Routing Protocol, Xiaohu Liu, Yuchen Zhang, Qingpo Fang, Leigang Sun Aug 2020

Design And Implementation Of Hardware-In-The-Loop Simulation Dynamic Routing Protocol, Xiaohu Liu, Yuchen Zhang, Qingpo Fang, Leigang Sun

Journal of System Simulation

Abstract: Against the problem of dynamic routing in network Hardware-In-The-Loop Simulation, on the basis of analysis of network HITL simulation principle, a dynamic routing protocol implementation scheme based on OMNeT++ was proposed. A method of routing message transform and a algorithm of time slice synchronize was proposed, overcoming the problem of routing message transform and system real-time. At the same time, using virtual IP technology for multi-host configuration, and OSPF dynamic routing protocol, the Hardware-In-the-Loop Simulation Dynamic Routing Protocol based on OMNeT++ was realized. The dynamic routing protocol with multi scenarios was verified and tested.


Order-Independent Image Compositing In Heterogeneous Environments, Liu Ning, Dengming Zhu, Zhaoqi Wang, Shi Min Aug 2020

Order-Independent Image Compositing In Heterogeneous Environments, Liu Ning, Dengming Zhu, Zhaoqi Wang, Shi Min

Journal of System Simulation

Abstract: Conventional image compositing algorithms are designed for homogeneous environments. These algorithms do not take heterogeneity into account and do not make use of the properties of an order-independent compositing operator. As for order-independent image compositing problems in a heterogeneous environment, these algorithms usually can not make full use of the resources. An order-independent image compositing algorithm in heterogeneous environments was proposed, which was able to distribute the workload according to computing and networking characteristics, and managed to optimize compositing scheme by utilizing the properties of order-independent operator. A comprehensive evaluation on the ns-3 network simulator was conducted. Experiment results …


Software Design And Implementation For Visualization System Automatic Optimization With Incorporation Of Feedback And Prediction, Xiaodong Wang, Fengju Kang, Gu Hao Aug 2020

Software Design And Implementation For Visualization System Automatic Optimization With Incorporation Of Feedback And Prediction, Xiaodong Wang, Fengju Kang, Gu Hao

Journal of System Simulation

Abstract: To develop high-fidelity and real-time visualization system, the problem of automatic optimization software of visualization system was brought forward. By analyzing the whole development process of visualization system, the attraction method of 3D models significance degree in final rendering image based on bounding box was designed. Combining with the prediction of efficiency of the rendering pipeline, the algorithm with incorporation of feedback and prediction for level of detail (LOD) selection was designed, and the interface and framework of the automatic optimization software were established, which implemented it with C++ programing language. The automatic optimization software implemented above was …


Ocean Hydrological Spatio-Temperal Data Visualization Based On Data Awareness, Caixia Li, Song Yuan, Wang Yi, Li Zhi, Xiaolin Cheng Aug 2020

Ocean Hydrological Spatio-Temperal Data Visualization Based On Data Awareness, Caixia Li, Song Yuan, Wang Yi, Li Zhi, Xiaolin Cheng

Journal of System Simulation

Abstract: Spatio-temporal data mining has emerged as an active research field focusing on the modeling and visualization of ocean hydrological data. A model of spatio-temporal data awareness (SDAM) was proposed, which gave details from three parts: 1) Description with data semantic tag for spatio-temporal context and value. 2) Awareness of spatial neighborhood semantic features by means of tri-linear interpolation; Awareness of temporal neighborhood semantic features by means of spatio-temporal frequent pattern mining; Developing database with the spatio-temporal coupling characteristics. 3) Developing feature cluster and application dataset by spatio-temporal clustering. With an application case of China's hydrological database, SDAM visualization on …


Design And Implementation Of Electromagnetic Spectrum Visualization System, Bin Fang, Ma Jie, Keyu Sun Aug 2020

Design And Implementation Of Electromagnetic Spectrum Visualization System, Bin Fang, Ma Jie, Keyu Sun

Journal of System Simulation

Abstract: Battlefield environment, filled with all kinds of devices with frequency electromagnetic signals, results in complex and rapidly changing electromagnetic environment. And the uncertainty brought by the complexity and the time variability not only makes it hard to predict the result of a war, but also leads to higher requirements for the current electromagnetic visualization platform serving for decision. To satisfy the visual needs for the electromagnetic spectrum data in the battlefield environment, the electromagnetic spectrum trend was designed in the perspective of temporal, spatial, frequency, and the energy domain. Four situations were proposed: equipment frequency radiation situation, spectrum …


Application Of Mutil-Level Fuzzy Algorithm In Ir Countermeasure Performance Integrated Evaluation, Li Fan, Geng Xu, Xiaojie Dong, Zehua Hong Aug 2020

Application Of Mutil-Level Fuzzy Algorithm In Ir Countermeasure Performance Integrated Evaluation, Li Fan, Geng Xu, Xiaojie Dong, Zehua Hong

Journal of System Simulation

Abstract: In order to improve the evaluation precision of countermeasure of IR guidance systems, a new method was proposed. The principle of multi-level fuzzy comprehension evaluation was analyzed, and a four level fuzzy comprehension evaluation was established. The result of the example under different simulation conditions shows its effectiveness.


Soft Sensor Of Concentration Of Sodium Aluminate Solution Based On Reduction Robust Lssvm, Rongling Sun, Xiaoshan Qian Aug 2020

Soft Sensor Of Concentration Of Sodium Aluminate Solution Based On Reduction Robust Lssvm, Rongling Sun, Xiaoshan Qian

Journal of System Simulation

Abstract: Taking into account of poor stability, radioactive, higher maintenance costs and lack of manual detection of serious lag issues for online testing instrument of sodium aluminate concentration, combined with the mechanism analysis of the evaporation process, selecting parameters that affect the concentration of sodium aluminate solution as the auxiliary variables, using weighted loss function of the least squares support vector machine (Least Squares Support Vector Machine, LSSVM), a robust soft measuring for the concentration of sodium aluminate solution was achieved. Schmidt method was used to simplify the matrix and reduce the computational complexity. Industrial process data simulation results show …


Integrated Modeling Method Of Flight Director And Guarantee Process, Yongliang Luo, Zhang Jun, Yuanhui Qin, Han Sheng, Yuanming Wang Aug 2020

Integrated Modeling Method Of Flight Director And Guarantee Process, Yongliang Luo, Zhang Jun, Yuanhui Qin, Han Sheng, Yuanming Wang

Journal of System Simulation

Abstract: The flight director and guarantee process as a kind of typical complex process, the modeling problem has become the current hot and difficult problem in the research field of the complex processes. An integrated modeling method of flight director and guarantee process was proposed combined with the typical process equipment air command and support building requirements. The following several aspects were mainly elaborated: The meta model of flight director process, service operation sequence modeling, machine process choreography. A prototype simulation and evaluation system was developed, and the rationality of the proposed method was analyzed combined with the application example.


Research And Simulation Of Cross Flow Heat Exchanger, Chengyun Wu, Guangwen Wang, Geping Li, Xudong Xin Aug 2020

Research And Simulation Of Cross Flow Heat Exchanger, Chengyun Wu, Guangwen Wang, Geping Li, Xudong Xin

Journal of System Simulation

Abstract: Based on cell concept, the lumped parameter method was applied and the parameters in single heat exchanger cell were deduced. Thereafter 1, 4, 9,100 cells heat exchanger simulation model was set up and the simulation error and its influencing factors were analyzed. To simplify the algorithm and increase the calculation speed, as well as improve the accuracy of cross flow heat exchanger, the simplified heat exchanger model was proposed and reviewed. The research results show that the calculation of simplified heat exchanger is precise and the algorithm is simple. The model could be widely applied in cross flow heat …


Study On Key Techniques About Refueling Simulation In Air, Hongtu Li, Guan Wei, Jijiang Song, Guangxing Zhao, Zewei Ma Aug 2020

Study On Key Techniques About Refueling Simulation In Air, Hongtu Li, Guan Wei, Jijiang Song, Guangxing Zhao, Zewei Ma

Journal of System Simulation

Abstract: The four key techniques of refueling flight simulation are studied on the base of a modern avion effective refueling flight simulation in the air. Characteristic of the usual scene simulation techniques is analyzed and the best scene simulation solution is found out, the theories of vortex interference and control & stability are explored deeply, and the models of vortex interference and control & stability are built with engineer data, system real time performance is researched, and the irregular back and fro of the refueling plane is worked off. the ideal result is harvested.


Practice Method For Modeling The Virtual Group Organization Synergy, Zhang Hui, Zhang Hong, Sikun Li, Zeng Liang Aug 2020

Practice Method For Modeling The Virtual Group Organization Synergy, Zhang Hui, Zhang Hong, Sikun Li, Zeng Liang

Journal of System Simulation

Abstract: The process to model the behaviors of virtual group has been divided into two stages, task interaction design and abstraction of the model. In the first stage, the task process is designed through task decomposition, interaction design and behaviors determination based on task decomposition. In the second one, the organization synergy model is presented by designs on three different levels, the structure level, the element level and the relation level, based on the design of the primary analysis. The method provides a framework to instruct the modeling work of virtual group organization synergy.


Research And Application Of Improved Cmms Descriptive Method, Shengjie Wang, Fengju Kang, Han Hong Aug 2020

Research And Application Of Improved Cmms Descriptive Method, Shengjie Wang, Fengju Kang, Han Hong

Journal of System Simulation

Abstract: In order to describe both the hybrid Agent behaviors and the mission space during the description process of combat system, the advantages of the PICS method and the CMMS describe method were combined. The ETDB describe method which stood for the entity was proposed by expanding the four factors of the CMMS describe method and was used for dividing the elements of MCSSU(The Man-machine Cooperative-combat System of Submarine and UUVs Formation) and concept modeling, and by describing an example, the method is compared with the traditional one. The concept models of MCSSU were formalized described by UML. The …


Calculation Of Vessel's Geometric Properties Based On Stl Model, Chunlei Liu, Yin Yong, Xiaofeng Sun, Xiufeng Zhang Aug 2020

Calculation Of Vessel's Geometric Properties Based On Stl Model, Chunlei Liu, Yin Yong, Xiaofeng Sun, Xiufeng Zhang

Journal of System Simulation

Abstract: To improve the accuracy of the ship geometric properties calculation and the real-performance of the program, a method based on STL triangular mesh model was proposed to calculate the ship geometric properties. SH polygon clipping algorithm in computer graphics was used to calculate the intersection of ship and water plane. By using of coordinates systems affine transformation, 3D water plane was changed to 2D plane to extract the profile contour. Because the waterlines are monotone polygon, Mass center insertion method was proposed to finish polygon triangulation, computing speed was improved. Bulk carrier "Taihang 128" was taken as an …


Modeling And Simulation Of Mooring System In Anchor Handling Simulator, Zhongxian Zhu, Yin Yong, Helong Shen Aug 2020

Modeling And Simulation Of Mooring System In Anchor Handling Simulator, Zhongxian Zhu, Yin Yong, Helong Shen

Journal of System Simulation

Abstract: Dynamics modeling and simulation of the mooring system are the key technologies in Anchor Handling Simulator (AHS), the model's quality and the visualization have great impact on the real-time, fidelity and immersed feeling in the scene simulation, and hence affect the quality of training on the anchor handling operation by using AHS. Based on the Lumped Mass Method the dynamics model of the mooring line was built up, and 4-order Runge-Kutta method was used to solve the model, and the computing speed could meet the demand on real-time; A model for the mooring line embedded in seabed soil was …


Gait Recognition Based-On Relative Motion Features And Kinect, Yang Ke, Dou Yong, Lv Shaohe Aug 2020

Gait Recognition Based-On Relative Motion Features And Kinect, Yang Ke, Dou Yong, Lv Shaohe

Journal of System Simulation

Abstract: Gait recognition Kinect is a very important biometric technology. Gait feature can be divided into two categories: static and dynamic. Some work found that although the essential characteristics of gait are motion, but the motion feature's recognition capability is limited. However, is the distinguishing ability of the motion itself limited, or existing features doesn't adequately capture the characteristics of motion? Relative distance-based motion features were proposed, and distances between the particular skeleton points and their changes were used to characterize the gait. The relative motion features were extracted without calculating the gait cycle, and with robustness. Experimental results …


Facial Expression Recognition With Independent Subspace Analysis Based Feature Learning, Yongjie Zhan, Long Fei, Yikun Bu Aug 2020

Facial Expression Recognition With Independent Subspace Analysis Based Feature Learning, Yongjie Zhan, Long Fei, Yikun Bu

Journal of System Simulation

Abstract: Hand-designed features (such as Gabor, LBP) has been widely employed in facial expression recognition. In the real-world applications of facial expression recognition, it is very difficult to achieve perfect face alignment because of the impact of complex background and the limitations of face alignment approaches. Independent Subspace Analysis (ISA) is an unsupervised feature learning method, which can be used to learn phase-invariant visual features from images. The problem of facial expression recognition based on ISA in the situation of not precise face alignment was investigated. Through analyzing the facial expression recognition performances with different subspace size, it was turned …


A Research Of Virtual Human Assembly Intelligent Simulation Technology, Yunfei Yang, Gu Yan, Xiumin Fan, Qichang He, Shiguang Qiu Aug 2020

A Research Of Virtual Human Assembly Intelligent Simulation Technology, Yunfei Yang, Gu Yan, Xiumin Fan, Qichang He, Shiguang Qiu

Journal of System Simulation

Abstract: Virtual human assembly simulation is an important part of virtual assembly simulation, and it is also a key link in the process of product design verification. To simulate the human operation more accurately, efficiently and really has been the research focus of the related areas. For the human body, which could be taken as a complex movement system, a multi rigid body model was built in virtual environment; the model was divided into different joint chains according to the operating characteristics of the human body and ergonomics knowledge was used to construct the model's optimal target function; a multi-objective …


Algorithm For Modeling Of Large-Scale Realistic Chinese Rose Based On Morphological Characteristics, Yang Meng, Wanghui Guo, Xiaoyu He, Lin Lin, Yang Gang Aug 2020

Algorithm For Modeling Of Large-Scale Realistic Chinese Rose Based On Morphological Characteristics, Yang Meng, Wanghui Guo, Xiaoyu He, Lin Lin, Yang Gang

Journal of System Simulation

Abstract: An algorithm of modeling individual plant and simulating large-scale garden scene of Chinese rose seasons was proposed based on morphological characteristics of plants. Real morphological data were accurately captured for the main organs of individual plant; These data should be deeply analyzed to gain the morphological properties, such as golden section; Topological relationships were established among the main stem and different high-order branches, branches and leaves. Meanwhile the main organs such as stem, leaves, flowers and thorns were simulated to complete the whole plant; The large-scale garden scene of Chinese rose were simulated based on the algorithm of Poisson …


Parallel Radiosity Based Light Distribution Simulation Within Virtual Plant Canopy, Can Hou, Liyu Tang, Chongcheng Chen, Yifei Yang Aug 2020

Parallel Radiosity Based Light Distribution Simulation Within Virtual Plant Canopy, Can Hou, Liyu Tang, Chongcheng Chen, Yifei Yang

Journal of System Simulation

Abstract: Owing to the computing-cost calculation of the form factor and the radiation energy in the traditional radiosity, a new method of parallel radiosity Based on CUDA (Compute Unified Device Architecture) was proposed to improve the performance of the implementation. Specifically, the implementation processes were as follows. The detailed 3D plant canopy model was loaded in the virtual scene. The solar altitude angle, solar azimuth and the radiation intensity were estimated according to the given time and the geographic location, and the light panel was generated afterwards, which was defined as radiation source on the basis of uniform triangular subdivision. …


Interactive Point Based Method For Soft Tissue Deformation In Surgical Simulation, Junliang Shan, Weixin Si, Xiaomeng Li, Wang Qiong, Yanjun Peng, Zhiyong Yuan, Pingan Wang Aug 2020

Interactive Point Based Method For Soft Tissue Deformation In Surgical Simulation, Junliang Shan, Weixin Si, Xiaomeng Li, Wang Qiong, Yanjun Peng, Zhiyong Yuan, Pingan Wang

Journal of System Simulation

Abstract: Although recent years have witnessed great improvement in the research of biomechanical simulation with user interactions for surgical simulation, it still suffers from many challenges such as computational model of soft tissue undergoing large deformation, collision detection, volume conservation, etc. A simple and efficient framework was proposed to meet these challenges. To well reproduce the mechanical response of organs, point based method was used to model the elastic solids undergoing large deformations. In addition, position based dynamics was adopted to model the objects collision, friction and volume conservation, which considerably improved the real-time performance and stability of complex interactions …


Dark Color Image Segmentation Method Integrated Mrf & Retinex, Yongchun Miao, Cheng Yan Aug 2020

Dark Color Image Segmentation Method Integrated Mrf & Retinex, Yongchun Miao, Cheng Yan

Journal of System Simulation

Abstract: Given the interference from noise, poor quality and low identification of the night images, it is difficult to segment them by traditional color image segmentation method. Therefore, a novel dark color image segmentation method integrated MRF&Retinex was proposed. The -LPG-PCA filtering model was built to filter out noise of an image. The recovery function of the denoised image was constructed, before converting RGB color space to HSV color space, and the MRF & Retinex model was built for image enhancement and color correction operation. The denoised and enhanced color image was segmented by the MRF&FCM …


Improved Method Of Extracting Hks Descriptors And Non-Rigid Classification Applications, Jingyu Jiang, Lili Wan Aug 2020

Improved Method Of Extracting Hks Descriptors And Non-Rigid Classification Applications, Jingyu Jiang, Lili Wan

Journal of System Simulation

Abstract: In order to make the HKS(heat kernel signature)have wider applicability in non-rigid shape analysis, an improved method of extracting HKS descriptors for unconnected non-rigid 3D models was proposed. The largest connected component was obtained. The HKS descriptors of the largest connected component were calculated and those descriptors of the boundary vertices and their 1-ring neighbors were excluded. For shape classifications, the dictionary was learned for each class based on the sparse representation theory. For a test model, each dictionary was utilized to sparsely represent its descriptor set, and the most appropriate dictionary was determined by the representation error, …


Algorithm For Sea Ice Model Scene Management Based On Spatial Index, Yuhao Sun, Yin Yong, Yicheng Jin, Gao Shuai Aug 2020

Algorithm For Sea Ice Model Scene Management Based On Spatial Index, Yuhao Sun, Yin Yong, Yicheng Jin, Gao Shuai

Journal of System Simulation

Abstract: In the process of modeling for scene visualization in marine simulator, ice region scene needs plenty of sea ice. Because of the numerous sea ice models, it may cause huge waste of time and space then make the whole simulation system in a poor real-time visualization situation, if there is no scientific or effective method. Applying quad-tree spatial index algorithm to sea ice dynamic modeling and management in ice region scene system of marine simulator, it could reduce consumption of time and space resources, improve the whole system fluency, and optimize the visualization of sea ice scene. And it …


Gpu-Based Fluid Collision Detection Method With Surface Of Three-Dimensional Scenes, Liangping Liu, Liu Zhen, Fang Hao, Cuijuan Liu, Tingting Liu Aug 2020

Gpu-Based Fluid Collision Detection Method With Surface Of Three-Dimensional Scenes, Liangping Liu, Liu Zhen, Fang Hao, Cuijuan Liu, Tingting Liu

Journal of System Simulation

Abstract: Virtual simulation of fluid phenomena is of great value, and SPH fluid simulation-based method can truly reflect the motion of the fluid. However, as the size of the fluid increasing, the computation becomes large, especially fluid collision detection in complex scenes significantly reduces the efficiency of fluid simulation. By using GPU to accelerate SPH physical calculation and collision detection, and use of new neighbors particles chain table building method for particles searching, can improve fluid simulation efficiency. By using voxel scene rasterization of sampling methods, the calculation of collision detection was speeded up, and the storage space was saved …


Research On Skin Color Image Post-Processing Methods For Gesture Recognition System, Renda Wang, Yin Yong, Shengwei Xing Aug 2020

Research On Skin Color Image Post-Processing Methods For Gesture Recognition System, Renda Wang, Yin Yong, Shengwei Xing

Journal of System Simulation

Abstract: Skin color region image post-processing methods suitable for gesture recognition system based on computer vision was proposed. To solve the problem of face and hand often occur simultaneously in the image frame, the training process and grouping strategy of AdaBoost face detector based on Haar-like template were studied, and a rapid culling method of face region based on fusion of color information was proposed. To reduce the influence of noise in skin color region image, impulse noise suppression and skin-like region rejection was proposed. The test results have shown that the proposed methods can greatly speed up the face …


Optimize Visual Hull With Concave Based On Depth Map, Guojun Chen, Wei Xin Aug 2020

Optimize Visual Hull With Concave Based On Depth Map, Guojun Chen, Wei Xin

Journal of System Simulation

Abstract: Traditional method based on color image can recover the boundary of an object, but it can't recover the concave part. Although reconstruction based on depth image can revert the concave part, but the result has bad boundary which means that the edge information lost seriously. The method that fused the depth and RGB image was proposed to solve the individual shortcomings. Based on space subdivision the origin visual hull was computed based RGB image and depth image individually. In the following step, the two type visual hulls were combined for analyzing concave area and then fused into one. A …


Research Of Light Weight 3d Models Repository And Key Techologies, Zhou Wen, Jinyuan Jia, Laixiang Wen, Zhao Long Aug 2020

Research Of Light Weight 3d Models Repository And Key Techologies, Zhou Wen, Jinyuan Jia, Laixiang Wen, Zhao Long

Journal of System Simulation

Abstract: With the development of computer graphics, the demand of the 3D model based on the Internet is growing; the related 3D models repository platform and service have emerged. The prototype system of 3D lightweight models repository, at the same time, it introduced the related cloud platform architecture and the framework of system platform was proposed and realized, moreover, the realized process of the system and some related key technologies were introduced, including lightweight JSON conversion algorithm, dynamic transaction management mechanism, adapter-based dynamic model loading mechanism, lightweight progressive meshes algorithm, sketch-based retrieval Using Content-Aware Hashing. …


Visual Analysis Method For Comparison And Association Of Pesticide Residue Detection Data In Foods, Yuchao Feng, Chen Yi, Liu Ying, Hongqian Chen Aug 2020

Visual Analysis Method For Comparison And Association Of Pesticide Residue Detection Data In Foods, Yuchao Feng, Chen Yi, Liu Ying, Hongqian Chen

Journal of System Simulation

Abstract: On the basis of existing researches, after having studied on the national pesticide residue data, a visual analysis method and interactions were proposed to visualize the data from different aspects, which was called Visual Analysis method of Comparisons and Associations(VACA). This method abandoned the visualization method of visualizing association relationships by connecting lines, and used interactions to visualize the associations relationships between two types of hierarchical data, which could avoid the visual clutters. This method also could compare the attributes of two trees with the same structure, such as the pesticide detection in the products of different …


Real-Time Visualization Method For Processing Data Stream, Hongqian Chen, Li Hui, Fang Yi, Chen Yi, Beibei Zhou Aug 2020

Real-Time Visualization Method For Processing Data Stream, Hongqian Chen, Li Hui, Fang Yi, Chen Yi, Beibei Zhou

Journal of System Simulation

Abstract: To visualize the status data of the procedure in real time, a visualization method supporting by the relating static model was proposed. The static models were built in the method. The processing status data were divided into some data segment matching to the static model. The dynamic model for each data segment was built based on the shape of the corresponding static model. Each part of the model was colorized or texturized based on its type or value. All the dynamic model and static model were linked and assembled due to its logical relation. The final visualization result …


Soft Shadow Map Method For Exploration Scene Simulation Of Lunar Rover, Yang Cheng, Jianliang Zhou, Geshi Tang, Li Xie, Guangming Chen, Shushi Liu Aug 2020

Soft Shadow Map Method For Exploration Scene Simulation Of Lunar Rover, Yang Cheng, Jianliang Zhou, Geshi Tang, Li Xie, Guangming Chen, Shushi Liu

Journal of System Simulation

Abstract: Scene simulation technology has gained a vast range of application in many different fields, such as aerospace measurement and controlling, by displaying the mission process and flight status in 3D real-time graphics interactively, which provided a comprehensive and intuitive controlling platform. The lunar exploration has been implemented with unmanned lunar rovers to detect the environments of the moon. Tele-operation was adopted to control the whole process by making and sending detecting plan and programming to the rover, in which the position of the sun was the key constraint condition. An effective real-time soft shadow map algorithm was presented to …