Research Of 3d Cloud Illumination Model Based On Importance Sampling,
2020
1. School of Computer and Software, Nanjing University of Information science and Technology, Nanjing 210044, China;;2. Jiangsu Engineering Center of Network Monitoring, Nanjing University of Information and Technology, Nanjing 210044, China;
Research Of 3d Cloud Illumination Model Based On Importance Sampling, Yonghua Xie, Fuxing Yuan, Wang Chang
Journal of System Simulation
Abstract: Currently existing 3D cloud simulation illumination models were confronted with the shortcomings such as complexity of implementation and low rendering efficiency. Herein a calculation method for illumination model based on importance sampling was proposed; Aiming at the problems of the old phase function, a new phase function was proposed to improve the rendering efficiency and quality. By the design of the importance function, the method did importance sampling in integrated interval and combined two phase functions to render the cloud. The results of the simulation show that the presented method has enhanced the rendering speed with the guarantee of …
Feature Model Visualized Configuration Method Of Digital Museum,
2020
1. Satellite Marine Tracking and Control Departement of China, Jiangyin 214431, China;;
Feature Model Visualized Configuration Method Of Digital Museum, Caixia Li, Song Yuan, Zhaoyang Feng, Wang Yi, Li Zhi
Journal of System Simulation
Abstract: It is an issue to be solved urgently transforming Digital Museum simulation resource description from natural language into visual simulation in order to reuse and share the resource expeditiously. During the analysis for feature model technique and Internet of Data (IOD), a method for feature model visualized configuration of digital museum based on IOD is proposed. The approach achieves the visualized configuration for simulation resource from domain feature model to application feature model which includes definition of feature model, description with feature data semantic tag and association semantic tag, visualized configuration with feature editor, feature association editor and …
Design And Application Of Underwater Unmanned Vehicle Simulation System For Navigation And Obstacle Avoidance,
2020
The 705th Research Institute, China Shipbuilding Industry Corporation, CSIC, Xi′an 710075, China;
Design And Application Of Underwater Unmanned Vehicle Simulation System For Navigation And Obstacle Avoidance, Zheng Wei, Qiming Zou, Wenxi Ni
Journal of System Simulation
Abstract: Accurate navigation and location, effective detection and realtime obstacle avoidance are the bases of Underwater Unmanned Vehicle (UUV) for long voyage mission accomplishment. To achieve intellectual demonstration and validation functions of UUV, which was studied on the base of integrated navigation model and dynamic obstacle-avoidance strategy on detection, the systems analysis aimed to simulated object characteristics was accomplished. Besides, models-component encapsulation method together with concurrent multi-thread simulation skeleton on discrete events was derived, followed by designed UUV navigation and obstacle-avoidance simulation system, compartmentalized function modules and marked-out simulation flow. The simulation application of UUV was achieved to …
Evaluation Of Anti-Multipath Performance To Satellite Navigation Signal Tracking On L1/E1/B1 Frequency Band,
2020
School of Information and Navigation, Air Force engineering University, Xi'an 710077, China;
Evaluation Of Anti-Multipath Performance To Satellite Navigation Signal Tracking On L1/E1/B1 Frequency Band, Mao Hu, Dewei Wu
Journal of System Simulation
Abstract: Aiming at analysis requirement to anti-multipath performance of satellite navigation signal system, on the basis of expounding modulation types of latest navigation signal system on L1/E1/B1(1575.42MHz) frequency band, the analytical expressions of code tracking multipath error envelope and carrier phase multipath error based non-coherent early minus late process discriminator and arctangent discriminator was deduced respectively, the effect of receiver correlation distance, receiver front-end bandwidth and navigation signal modulation types to multipath error were analyzed through simulation. The results show that B1-C open service signal of BDS should adopt MBOC(6,1,1/11) modulation of similarly Galileo E1OS combination mode, and B1 …
Simulation Contrast Analysis On Rigid And Flexible Movements Of Multi-Fins Coordinated Propulsion Mode,
2020
1. School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013, China;;2. School of Mechanical Engineering, Suzhou University of Science and Technology, Suzhou 215009, China;
Simulation Contrast Analysis On Rigid And Flexible Movements Of Multi-Fins Coordinated Propulsion Mode, Xie Ou, Boquan Li, Yan Qin
Journal of System Simulation
Abstract: A novel type of bionic underwater hybrid propulsion mode was proposed. By the means of the coordination control of the multi-fins, a propulsion mode combines the undulation propulsion of fish and the jet propulsion of jellyfish was developed, and was capable of achieving a serial of motions: undulating, jetting, turning, submerging, emerging and braking. The rigid and flexible water stabilizer kinematics model was established and the numerical simulation was performed for undulation and jet propulsion mode of the rigid and flexible water stabilizer by using a CFD method. The simulation results show that the dynamic characteristics and swimming performance …
Identification Of Wiener Model Based On Improved Differential Evolution (Sade) Algorithm,
2020
1. School of sciences, Xi'an University of Technology, Xi'an 710054;;
Identification Of Wiener Model Based On Improved Differential Evolution (Sade) Algorithm, Xiaoping Xu, Bai Bo, Fucai Qian
Journal of System Simulation
Abstract: To identify the parameters of nonlinear Wiener model, a new identification method was put forward based on a SADE algorithm. Its basic idea is as follows: the Sigmoid function and adaptive mutation operator were adopted to improve the mutation operation part of the basic differential evolution algorithm, accordingly, the disadvantages of the basic differential evolution algorithm, such as premature convergence, instability, etc, were effectively overcome. The proposed algorithm was used to parameter identification problem of Wiener model; moreover, the accuracy of identification was well improved. In the numerical simulation, compared with other relevant existing algorithms, simulation results show that …
Image Denoising Algorithm Based On Method Noise Sparse Representation Dictionary Learning,
2020
College of Electronics and Information Engineering, Hunan University of Science and Engineering, Yongzhou 425199, China;
Image Denoising Algorithm Based On Method Noise Sparse Representation Dictionary Learning, Lishao Huang, Haiying Wen, Sisi Gu
Journal of System Simulation
Abstract: For the shortcoming of losting partial texture information with image denoising process, the image denoising algorithm based on method noise sparse representation was proposed. The method noise, which was defined as the difference between the noisy and the denoised image, was obtained by guided filter. Then redundant dictionary was learned by improved dictionary learning method and the method noise. The image texture information in method noise was extracted by the learning dictionary, and image was restored by the extracted image texture information and denoised image by guided filter. The experimental results demonstrate that the peak signal to noise ratio …
Color Face Image Recognition Based On Lbpt Method,
2020
College of Computer Information Engineering ,Jiangxi Normal University, Nanchang 330022, China;
Color Face Image Recognition Based On Lbpt Method, Jihua Ye, Yahui Chen, Shimin Wang
Journal of System Simulation
Abstract: Aiming to the shortcomings of exiting algorithm to obtain better color face image information for color facial image recognition, the LBPT algorithm was proposed to realize the high efficiency recognition of color face image. LBPT algorithm reflected the texture features of gray image through adaptively obtaining neighborhood radius, ascertaining the relationship between neighborhood radius and neighborhood pixel number, setting threshold. The RGB color model was used to separate the color face image into the R,G,B three component diagrams. The LBPT algorithm was used to obtain the feature of the component diagrams. In order to realize further recognition, the method …
Image Segmentation Based On Active Contour Derived By Signed Pressure Force Function,
2020
1. College of Mathematics and information Science, Wenzhou University, Zhejiang 325035, China;;
Image Segmentation Based On Active Contour Derived By Signed Pressure Force Function, Hongli Lü, Renfang Wang
Journal of System Simulation
Abstract: Distance regularized level set evolution model for image segmentation has some shortcomings. Initial curve is not flexible and the direction of curve evolution is not self-adaptive. A new active contour model was proposed. A signed pressure force function (SPF) was constructed, integrating local information and global information, and shown to modulate the signs of pressure forces inside and outside the region of object; Then SPF was embed to DRLSE model to solve the problem of requiring the initial contour to surround (let in or keep out) the objects. Experimental results show that the new model's initial contour can be …
Opnet Simulation Method For Underwater Acoustic Networks Based On Chirp Spread Spectrum,
2020
1. College of Information Science and Technology, Communication Engineering, Xiamen University, Xiamen 361005, China;;2. Key Laboratory of Underwater Acoustic Communication and Marine Information Technology, Ministry of Education, School of Information Science and Technology, Xiamen University, Xiamen 361005, China;
Opnet Simulation Method For Underwater Acoustic Networks Based On Chirp Spread Spectrum, Wencong Li, Yuan Fei, Zhangting Zhong, En Cheng
Journal of System Simulation
Abstract: Underwater acoustic(UWA) network protocol simulation on OPNET software could not follow the changing of channel structure and did not support custom modulation. In view of the limitations mentioned, a more realistic method of UWA protocol simulation on OPNET was introduced. UWA network ALHOA protocol simulation was token as an example. The physical layer modulation customized was called π/4-DM-DQPSK which was based on Chirp Spread Spectrum. In Matlab, the system would generate a modulation curve which would then be imported into OPNET to adjust the configuration of other pipelines. The simulation results of ALHOA protocol was verified in two Bellhop …
Boundary Conditions For Model Of Random Kelvin Cell Open-Cell Foam And Its Application On Open-Cell Aluminum Foam,
2020
1. Department of Computer and Information Engineering, Huainan Normal University, Huainan 232001, China;;
Boundary Conditions For Model Of Random Kelvin Cell Open-Cell Foam And Its Application On Open-Cell Aluminum Foam, Minju Qi, Guangfa Gao
Journal of System Simulation
Abstract: The random Kelvin cell open-cell foam model, the further investigations on the boundary conditions of the model were carried out using the Python scripting language and the commercial code ABAQUS. The ‘floating' edges in boundary, owing to being cut with slanted planes, were eliminated. The compressive behaviors of the material under free boundary condition and fixed boundary condition were investigated and comparatively analyzed. On the basis of the above results, the periodic boundary condition was developed, and the method of setting the periodic boundary condition under several different conditions was discussed. The methodology for the design and implement for …
Simulation Study On Mslb Plus Sgtr And Si Failure Process In Reactor Vessel Based On Maap5,
2020
China Nuclear Power Simulation Technology Co. Ltd, Shenzhen 518118, China;
Simulation Study On Mslb Plus Sgtr And Si Failure Process In Reactor Vessel Based On Maap5, Xianrong Wu, Huiming Wei, Xuefeng Su, Wu Fan
Journal of System Simulation
Abstract: NPP Main Steam Line Break (MSLB) plus Steam Generator Tube Rupture (SGTR) and Safety Injection (SI) failure is severe accident (SA) process with complex phenomena in reactor vessel. The severe accident process serial was analyzed using the latest version of Modular Accident Analysis Program 5 (MAAP5). The whole trends of the simulation result agreed well with the anticipated process serial, which could provide training material to the full scope simulator and the related evidence to make detailed severe accident management guidelines (SAMG).
Path Planning And Control Simulation Of Unpowered Unmanned Aerial Vehicle (Uav) Returning To The Airport,
2020
1. Institute of Aircraft Design, Department of Mechanics and engineering science, Fudan University, Shanghai 200433, China;;
Path Planning And Control Simulation Of Unpowered Unmanned Aerial Vehicle (Uav) Returning To The Airport, Yijun Zhang, Yiqun Dong, Zhan Guang, Jianliang Ai
Journal of System Simulation
Abstract: The unpowered Unmanned Aerial Vehicle (UAV) return to the airport unpoweredly is a link of large risk and complex technology during the flight, and it is the key stage which affects the flight safety of the UAV. The basic control strategy and path planning of the unpowered UAV's back to the airport were studied, and the method which calculated the average drag of the return was proposed. Under the condition of multiple constraints, the flight control model of the UAV's return was established. It is proved that the result of the simulation is effective and has built a foundation …
Simulation Of Three Level Inverter Neutral Point Potential Control Based On Three Level Dc/Dc Converter,
2020
1. University of Shanghai for Science and Technology, Shanghai 200093, China;;
Simulation Of Three Level Inverter Neutral Point Potential Control Based On Three Level Dc/Dc Converter, Kun Xia, Xiaodi Li, Xiaobo Ding, Yanneng Zeng, Yiming Wang, Xu Po
Journal of System Simulation
Abstract: The DC capacitor voltage unbalancing of NPC three-level inverter not only makes the AC output performance worse, but also reduces the DC capacitors' service life and even damages the power devices. A method based on three-level DC/DC converter was put forward to control the neutral point potential of three-level inverter. This method realized power conversion with three-level DC/DC converter topology, boosting voltage and stabilizing the neutral point potential of DC link at the same time. It would regulate switches working states according to the constraint rules on the sum of switches off time deciding bus voltage and the ratio …
Application Of Recursive Least Square Method In Identication Of Dehydrogenation Reator,
2020
Key Laboratory of Industrial Computer Control Engineering of Hebei Province, Yanshan University, Qinhuangdao, 066004, China;
Application Of Recursive Least Square Method In Identication Of Dehydrogenation Reator, Guoyou Li, Ningning Gao, Wenhua Xia
Journal of System Simulation
Abstract: The current production methods of styrene at home and abroad are mainly dhydrogenation of ethylbenzene which accounts for more than 90% of styrene production capacity in the world. To save energy, it was needed to optimize the system and its premise was to know the mathematical model of ethylbenzene dehydrogenation reactor. Due to the complexity of the reactor internal structure, mechanism modeling was more difficult to establish objective and accurate mathematics models. To solve this problem, it was used recursive least squares to conduct parameter identification. On the basis of actual plant data, ethylbenzene dehydrogenation reactor mathematical model was …
Simulation Research Of Maglev Train During Uphill And Downhill Process,
2020
Key Laboratory of Magnetic Suspension Technology and Maglev Vehicle, Ministry of Education,Southwest Jiaotong University, Chengdu 610031, China;
Simulation Research Of Maglev Train During Uphill And Downhill Process, Songqi Li, Kunlun Zhang, Guoqing Liu, Chen Yin
Journal of System Simulation
Abstract: In the low speed EMS maglev test line experiments in Zhuzhou, it was found that vehicles are prone to hit the tracks, when the maglev train travels uphill or downhill through the tracks with slopes. This seriously affected the safety and comfort of the vehicle. In order to study the problem, a single low speed EMS maglev train carriages-track model with four degrees of freedom was built. It simulated and analyzed dynamic behaviors of the vehicle going uphill on different track curves, under different vehicle -track parameters. The simulation results show that the vehicle parameters, vehicle speed, and the …
Modeling Method Based On Reachable Set For Safety Path In Autonomous Vehicle Obstacle Avoidance,
2020
1. School of Traffic & Vehicle Engineering, Shandong University of Technology, Zibo 255000, China;;2. School of Computer and Electronic Information Engineering, Shandong Yingcai University, Jinan 250104, China;
Modeling Method Based On Reachable Set For Safety Path In Autonomous Vehicle Obstacle Avoidance, Cao Kai, Xiaoxiao Huang, Yu Yun, Liu Chun
Journal of System Simulation
Abstract: In view of problem in all possible uncertain behavior of vehicle unable existed by the traditional path planning algorithm, a modeling method was proposed which deemed a moving vehicle as a hybrid system switching dynamically between continuous and discrete mode, modeled an optimal trajectory for vehicle obstacle avoidance by using a single security target location, and built a safe state reachable set based on the trajectory beam of multiple security target locations. On this basis, the condition of the inevitable collision of vehicle was analyzed, and the optimal control problem with loose constraints for the vehicle obstacle avoidance was …
Numerical Simulation For Influence Of Baffle Length On Hydraulic Characteristics In Radial Sedimentation Tanks,
2020
State Key Laboratory of Eco-Hydraulic Engineering in Shaanxi, Xi'an University of Technology, Xi'an 710048, China;
Numerical Simulation For Influence Of Baffle Length On Hydraulic Characteristics In Radial Sedimentation Tanks, Wenli Wei, Zewei Zhang, Yunfei Hong, Yuling Liu
Journal of System Simulation
Abstract: The VOF (volume of fluid) method was applied to track the free water surface, and the RNG turbulent model was used to close the two-phase flow time-averaged equations. The influence of inlet vertical baffle with different lengths on hydraulic characteristics in radial sedimentation tank was simulated and analyzed. The control equations were discretized using the finite volume method. Velocity and pressure were solved using the PISO (Pressure-Implicit with Splitting of Operators) algorithm. The research results show that: the long length feed flow baffle model has a smaller recirculation zone, better velocity field distribution than short length baffle, and the …
Research Of Visualization Of Road Guide Sign Panel Based On Combination Of Guiding Information,
2020
1. Guangdong Provincial Key Laboratory of Intelligent Transportation System, Guangzhou 510006, China;;2. School of Engineering, Sun Yat-sen University, Guangzhou 510006, China;;
Research Of Visualization Of Road Guide Sign Panel Based On Combination Of Guiding Information, Zhongming Niu, Huang Min, Yuan Yuan, Li Min
Journal of System Simulation
Abstract: In order to realize the intelligent management of road guide signs, a method of visualization of road guide sign panel based on the flexible combination of guiding information was proposed. As a consequence of analysis for structures of guide sign panel, the message on the guide sign panel was decomposed into guiding information, and then visualization function was proposed. The panel style was determined by the physical and logical topology of guiding intersection dynamically with the help of guide sign system database. Then the composition of geography information and guiding information was utilized in the process of visualization …
Learning To Learn Kernels With Variational Random Features,
2020
Inception Institute of Artificial Intelligence
Learning To Learn Kernels With Variational Random Features, Xiantong Zhen, Haoliang Sun, Yingjun Du, Jun Xu, Yilong Yin, Ling Shao, Cees Snoek
Machine Learning Faculty Publications
We introduce kernels with random Fourier features in the meta-learning framework for few-shot learning. We propose meta variational random features (MetaVRF) to learn adaptive kernels for the base-learner, which is developed in a latent variable model by treating the random feature basis as the latent variable. We formulate the optimization of MetaVRF as a variational inference problem by deriving an evidence lower bound under the meta-learning framework. To incorporate shared knowledge from related tasks, we propose a context inference of the posterior, which is established by an LSTM architecture. The LSTMbased inference network effectively integrates the context information of previous …
