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Color Face Image Recognition Based On Lbpt Method, Jihua Ye, Yahui Chen, Shimin Wang 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, Hongli Lü, Renfang Wang 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, Wencong Li, Yuan Fei, Zhangting Zhong, En Cheng 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, Minju Qi, Guangfa Gao 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, Xianrong Wu, Huiming Wei, Xuefeng Su, Wu Fan 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, Yijun Zhang, Yiqun Dong, Zhan Guang, Jianliang Ai 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, Kun Xia, Xiaodi Li, Xiaobo Ding, Yanneng Zeng, Yiming Wang, Xu Po 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, Guoyou Li, Ningning Gao, Wenhua Xia 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, Songqi Li, Kunlun Zhang, Guoqing Liu, Chen Yin 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, Cao Kai, Xiaoxiao Huang, Yu Yun, Liu Chun 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, Wenli Wei, Zewei Zhang, Yunfei Hong, Yuling Liu 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, Zhongming Niu, Huang Min, Yuan Yuan, Li Min 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 …


An Application Of The Unscented Kalman Filter For Spacecraft Attitude Estimation On Real And Simulated Light Curve Data, Kent A. Rush 2020 California Polytechnic State University, San Luis Obispo

An Application Of The Unscented Kalman Filter For Spacecraft Attitude Estimation On Real And Simulated Light Curve Data, Kent A. Rush

Master's Theses

In the past, analyses of lightcurve data have been applied to asteroids in order to determine their axis of rotation, rotation rate and other parameters. In recent decades, these analyses have begun to be applied in the domain of Earth orbiting spacecraft. Due to the complex geometry of spacecraft and the wide variety of parameters that can influence the way in which they reflect light, these analyses require more complex assumptions and a greater knowledge about the object being studied. Previous investigations have shown success in extracting attitude parameters from unresolved spacecraft using simulated data. This paper presents a focused …


A Systematic Media Frame Analysis Of 1.5 Million New York Times Articles From 2000 To 2017, Haewoon KWAK, Jisun AN 2020 Singapore Management University

A Systematic Media Frame Analysis Of 1.5 Million New York Times Articles From 2000 To 2017, Haewoon Kwak, Jisun An

Research Collection School Of Computing and Information Systems

Framing is an indispensable narrative device for news media because even the same facts may lead to conflicting understandings if deliberate framing is employed. Therefore, identifying media framing is a crucial step to understanding how news media influence the public. Framing is, however, difficult to operationalize and detect, and thus traditional media framing studies had to rely on manual annotation, which is challenging to scale up to massive news datasets. Here, by developing a media frame classifier that achieves state-of-the-art performance, we systematically analyze the media frames of 1.5 million New York Times articles published from 2000 to 2017. By …


Busting Myths And Dispelling Doubts About Covid-19, Mark FINDLAY 2020 Singapore Management University

Busting Myths And Dispelling Doubts About Covid-19, Mark Findlay

Research Collection Yong Pung How School Of Law

The Centre for AI and Data Governance (CAIDG) at Singapore Management University (SMU) has embarked over past months on a programme of research designed to confront concerns about the pandemic and its control. Our interest is primarily directed to the ways in which AI-assisted technologies and mass data sharing have become a feature of pandemic control strategies. We want to know what impact these developments are having on community confidence and health safety. In developing this work, we have come across many myths that need busting.


Next-Term Grade Prediction: A Machine Learning Approach, Audrey Tedja WIDJAJA, Lei WANG, Nghia TRUONG TRONG, Aldy GUNAWAN, Ee-peng LIM 2020 Singapore Management University

Next-Term Grade Prediction: A Machine Learning Approach, Audrey Tedja Widjaja, Lei Wang, Nghia Truong Trong, Aldy Gunawan, Ee-Peng Lim

Research Collection School Of Computing and Information Systems

As students progress in their university programs, they have to face many course choices. It is important for them to receive guidance based on not only their interest, but also the "predicted" course performance so as to improve learning experience and optimise academic performance. In this paper, we propose the next-term grade prediction task as a useful course selection guidance. We propose a machine learning framework to predict course grades in a specific program term using the historical student-course data. In this framework, we develop the prediction model using Factorization Machine (FM) and Long Short Term Memory combined with FM …


Simulation-Based An Exploratory Analysis Of Drone Air Strike On Saudi Oilfields, Jiajun Zhang, Xiaochao Qian, Jinpeng Zhou, Xuanling Wang, Zhifeng Lu 2020 Shanghai Electro-Mechanical Engineering Institute, Shanghai 201109, China;

Simulation-Based An Exploratory Analysis Of Drone Air Strike On Saudi Oilfields, Jiajun Zhang, Xiaochao Qian, Jinpeng Zhou, Xuanling Wang, Zhifeng Lu

Journal of System Simulation

Abstract: The incident of air strike in Sandi Arabia in September 2019 is taken as an example,A rapid analysis method for crisis events based on simulation is proposed. Combining the simulation with the exploratory analysis, the uncertainty of crisis events is comprehensively analyzed and dealt with. According to the public information of the incidents details from Sandi Arabia, Yemen, the combat situation of the air strike is replayed based on the wargaming. The rationality and authenticity of the details in the event statement is verified and can also provide reference to the development and combat research of the “Low, Small …


Multi-Tank Adaptive Scheduling Algorithm And Simulation For Ship Stability Realization, Xiong Yong, Xuanzhuo Liang, Zhang Jia 2020 Wuhan University of Technology, Wuhan 430063, China;

Multi-Tank Adaptive Scheduling Algorithm And Simulation For Ship Stability Realization, Xiong Yong, Xuanzhuo Liang, Zhang Jia

Journal of System Simulation

Abstract: Aiming at the influence of the oil tank on the floating state and stability of the ship, the multi-tank adaptive dispatching control algorithm to maintain the stability of the ship is studied. The automatic floating state adjustment simulation system of the ship is realized by the WinCC (Windows Control Center) configuration software. For the system architecture, the Boolean logic table is used to construct the connection relationships of the oil tanks, pumps and pipelines, and the amount of oil exchange between the cabins is calculated according to the floating equation, and the balance of the floating state in the …


Simulation-Based Effectiveness Evaluation For System-Of-System Under Multi-Equipment Collaboration, Ma Ning, Shenglin Lin 2020 1. Anshan Branch, Liaoning Police College, Anshan 114051, China;;

Simulation-Based Effectiveness Evaluation For System-Of-System Under Multi-Equipment Collaboration, Ma Ning, Shenglin Lin

Journal of System Simulation

Abstract: Complex coordination exists among the various equipment in the system-of-system (SoS) operational process. The influence relationship among the various indexes is ignored in the traditional effectiveness evaluation methods. Aiming at this, a new effectiveness evaluation approach for the SoS is proposed. Numerous evaluation data is analyzed, based on the association rules mining, to obtain the influence among the effectiveness indexes. The networked evaluation index system is constructed, and the effectiveness integration evaluation is realized based on the analytic network process. The feasibility and validity of the proposed method are verified by evaluating the effectiveness of an air defense SoS.


Identification Method For Fractional-Order Systems Based On Haar Wavelet Operational Matrix, Yuanlu Li, Li Teng, Baoying Liu 2020 1. School of Automation, Nanjing University of Information Science & Technology, Nanjing 210044, China;;2. Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology, Nanjing University of Information Science & Technology, Nanjing 210044, China;

Identification Method For Fractional-Order Systems Based On Haar Wavelet Operational Matrix, Yuanlu Li, Li Teng, Baoying Liu

Journal of System Simulation

Abstract: Studies have shown that the dynamical systems can be more accurately described by the fractional-order systems because its order can be any number. That’s why the fractional-order systems are being paid more and more attention. However, how to create a fractional-order system is still in the exploratory stage. Considering the nonlocal features of the fractional differentiation, a method for the fractional-order system identification is proposed by taking the Haar wavelet operational matrix. The proposed method can reduce the dimension of the operational matrix by abandoning the high frequency coefficients of the input and output signals so that the buffer …


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