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Articles 9001 - 9030 of 25628

Full-Text Articles in Computer Engineering

Towards Distributed Node Similarity Search On Graphs, Tianming Zhang, Yunjun Gao, Baihua Zheng, Lu Chen, Shiting Wen, Wei Guo Jun 2020

Towards Distributed Node Similarity Search On Graphs, Tianming Zhang, Yunjun Gao, Baihua Zheng, Lu Chen, Shiting Wen, Wei Guo

Research Collection School Of Computing and Information Systems

Node similarity search on graphs has wide applications in recommendation, link prediction, to name just a few. However, existing studies are insufficient due to two reasons: (i) the scale of the real-world graph is growing rapidly, and (ii) vertices are always associated with complex attributes. In this paper, we propose an efficiently distributed framework to support node similarity search on massive graphs, which considers both graph structure correlation and node attribute similarity in metric spaces. The framework consists of preprocessing stage and query stage. In the preprocessing stage, a parallel KD-tree construction (KDC) algorithm is developed to form a newly …

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Work-In-Progress: Augmented Reality System For Vehicle Health Diagnostics And Maintenance, Yuzhong Shen, Anthony W. Dean, Rafael Landaeta Jun 2020

Work-In-Progress: Augmented Reality System For Vehicle Health Diagnostics And Maintenance, Yuzhong Shen, Anthony W. Dean, Rafael Landaeta

Electrical & Computer Engineering Faculty Publications

This paper discusses undergraduate research to develop an augmented reality (AR) system for diagnostics and maintenance of the Joint Light Tactical Vehicle (JLTV) employed by U.S. Army and U.S. Marine Corps. The JLTV’s diagnostic information will be accessed by attaching a Bluetooth adaptor (Ford Reference Vehicle Interface) to JLTV’s On-board diagnostics (OBD) system. The proposed AR system will be developed for mobile devices (Android and iOS tablets and phones) and it communicates with the JLTV’s OBD via Bluetooth. The AR application will contain a simplistic user interface that reads diagnostic data from the JLTV, shows vehicle sensors, and allows users …

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Learning From Digital Failures? The Effectiveness Of Firms’ Divestiture And Management Turnover Responses To Data Breaches, Gui-Deng Say, Gurneeta Vasudeva Jun 2020

Learning From Digital Failures? The Effectiveness Of Firms’ Divestiture And Management Turnover Responses To Data Breaches, Gui-Deng Say, Gurneeta Vasudeva

Research Collection Lee Kong Chian School Of Business

We examine whether firms learn from digital technology failures in the form of data breach events, based on the effectiveness of their failure responses. We argue that firms experiencing such technological failures interpret them broadly as organizational problems, and undertake unrelated divestitures and top management turnover to achieve better standardization and to remove dysfunctional routines. We test our hypotheses on unrelated subsidiary divestitures and chief technology officer (CTO) turnovers undertaken by 8,760 publicly traded U.S. firms that were at risk of experiencing data breaches in- volving the loss of personally identifiable information during the period 2005–2016. We find that data …

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Mining User-Generated Content Of Mobile Patient Portal: Dimensions Of User Experience, Mohammad Al-Ramahi, Cherie Noteboom Jun 2020

Mining User-Generated Content Of Mobile Patient Portal: Dimensions Of User Experience, Mohammad Al-Ramahi, Cherie Noteboom

Research & Publications

Patient portals are positioned as a central component of patient engagement through the potential to change the physician-patient relationship and enable chronic disease self-management. The incorporation of patient portals provides the promise to deliver excellent quality, at optimized costs, while improving the health of the population. This study extends the existing literature by extracting dimensions related to the Mobile Patient Portal Use. We use a topic modeling approach to systematically analyze users’ feedback from the actual use of a common mobile patient portal, Epic’s MyChart. Comparing results of Latent Dirichlet Allocation analysis with those of human analysis validated the extracted …

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Flux-Switching Permanent Magnet Machines: A Review Of Opportunities And Challenges—Part I: Fundamentals And Topologies, Hao Chen, Ayman M. El-Refaie, Nabeel A. O. Demerdash Jun 2020

Flux-Switching Permanent Magnet Machines: A Review Of Opportunities And Challenges—Part I: Fundamentals And Topologies, Hao Chen, Ayman M. El-Refaie, Nabeel A. O. Demerdash

Electrical and Computer Engineering Faculty Research and Publications

Flux-switching permanent magnet (FSPM) machines have been gaining interest over the last few decades. This is due to the several advantages that this type of machines provides. These advantages include high torque density due to the flux-focusing effects, favorable thermal management due to the location of PMs on the stator, passive and hence robust rotor structure which is suitable for high-speed applications, etc. The two-part companion articles are going to provide a comprehensive analysis of FSPM machines in terms of opportunities and challenges. In the first part of these two-part series, it covers the principle theory, computation methods, various topologies …

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Sensing, Computing, And Communications For Energy Harvesting Iots: A Survey, Dong Ma, Guohao Lan, Mahbub Hassan, Wen Hu, Sajal K. Das Jun 2020

Sensing, Computing, And Communications For Energy Harvesting Iots: A Survey, Dong Ma, Guohao Lan, Mahbub Hassan, Wen Hu, Sajal K. Das

Research Collection School Of Computing and Information Systems

With the growing number of deployments of Internet of Things (IoT) infrastructure for a wide variety of applications, the battery maintenance has become a major limitation for the sustainability of such infrastructure. To overcome this problem, energy harvesting offers a viable alternative to autonomously power IoT devices, resulting in a number of battery-less energy harvesting IoTs (or EH-IoTs) appearing in the market in recent years. Standards activities are also underway, which involve wireless protocol design suitable for EH-IoTs as well as testing procedures for various energy harvesting methods. Despite the early commercial and standards activities, IoT sensing, computing and communications …

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Simulation Modeling Method Of Distributed Supply Chain Based On Has, Wang Jian, Huang Yang Jun 2020

Simulation Modeling Method Of Distributed Supply Chain Based On Has, Wang Jian, Huang Yang

Journal of System Simulation

Abstract: There are some shortcomings in simulation modeling method of distributed supply chain based on High Level Architecture (HLA) and Supply Chain Operation Reference (SCOR), which result in low development efficiency of system simulation modeling and low reusability of simulation objects inside the federates. To solve the problems, a simulation modeling method of distributed supply chain based on HAS(HLA-Agent-SCOR) was put forward. The supply chain structure modeling based on HLA for building structure model of supply chain was discussed. Modeling of Agent blocks integrating processes from SCOR and modeling of federates based on Agent were illustrated to create model of …

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Multi-Robots Global Path Planning Based On Pso Algorithm And Cubic Spline, Qiang Ning, Gao Jie, Fengju Kang Jun 2020

Multi-Robots Global Path Planning Based On Pso Algorithm And Cubic Spline, Qiang Ning, Gao Jie, Fengju Kang

Journal of System Simulation

Abstract: There are shortcomings such as premature convergence, high encoding dimension and unsmooth path for particle swarm optimization (PSO) algorithm to solve the robot path planning problem under free space. The particle coding is coordinates of several path nodes in the environment. The number of spline curves and the maximum turnings of path were determined by the number of path nodes. The cubic spline function was used to interpolate on the path of the starting point, path nodes and target point, thus a full path which was formed by connecting all interpolation points was obtained. Simulation results show that …

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Improved Marching Cubes Algorithmand Its Three-Dimensional Meteorological Simulation, Shuoben Bi, Lu Yuan, Xiaowen Zeng, Mingyue Lu, Yonghua Zhang Jun 2020

Improved Marching Cubes Algorithmand Its Three-Dimensional Meteorological Simulation, Shuoben Bi, Lu Yuan, Xiaowen Zeng, Mingyue Lu, Yonghua Zhang

Journal of System Simulation

Abstract: Methodof obtaining intersection points of isosurface and vowex by linear interpolation in original Marching Cubes algorithm has been replaced by the method of trisecting element boundaries. The problem of linear interpolation not suitable for meteorological data simulation is therefore solved and the number of triangular facets in isosurfacemapping is effectively reduced. While reducing redundancy and improving mapping speed, the quality of isosurface mapping is further improved. The improved Marching Cubes algorithm is applied to the simulation of meteorological model data, i.e., the isosurface of WRF data, and good results are obtained in both the speed of image rendering and …

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Trajectory Capture And Sway Frequency Analysis Of Trees Based On Kinect, He Peng, Shaojun Hu, Dongjian He Jun 2020

Trajectory Capture And Sway Frequency Analysis Of Trees Based On Kinect, He Peng, Shaojun Hu, Dongjian He

Journal of System Simulation

Abstract: The morphology and structure of plants were complex. It is of great significance to investigate the inherent motion law of plants under the action of external force, such as realistic animation formation, plant pruning, vibration picking and forest protection. A low cost outdoor tree complex motion capture method was explored, and the relationship between the stem motion and the external force was analyzed. The Kinect was used to capture the branches motion; MeanShift algorithm was used for tracking branches markers and the three-dimensional trajectory of the trunk was extracted according to the principle of Kinect coordinate transformation. A method …

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Realistic Real-Time Road Rendering Technology Based On Road Boundaryalpha-Map, Jinlian Du, Shang Xin, Fengchao Zhao Jun 2020

Realistic Real-Time Road Rendering Technology Based On Road Boundaryalpha-Map, Jinlian Du, Shang Xin, Fengchao Zhao

Journal of System Simulation

Abstract: A method of realistic real-time rendering based on road boundary alpha-map was proposed to eliminate the blur and aliasing issues produced by traditional rendering method based on buffer mechanism. In the method, the road was generated by buffer mechanism based on grid model of terrain, and the road's borders were constructed by analyzing the characteristics of road boundary grids. Based on these, three types of road boundary alpha-maps were designed for producing the road borders with realistic visual effects. Experiment shows that the method can improve the rendering realism of the road borders than traditional method. Another advantage of …

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Simulation On Psychosocial Adaption Of Urban New Migrants Based On Catastrophe Theory, Zhao Xu, Chuanchao Huang, Bin Hu Jun 2020

Simulation On Psychosocial Adaption Of Urban New Migrants Based On Catastrophe Theory, Zhao Xu, Chuanchao Huang, Bin Hu

Journal of System Simulation

Abstract: Based on the mental recovery and adaptive behavior translation of the new urban migrants, a two system decision-making model for psychological adaption was built. The simulation research of psychosocial adaption process was studied through the stochastic catastrophe theory and the specific artificial social environment. Simulation experiments indicate that the sustained pressure-bearing suffers from outside situation and the policy system result in the fluctuation of migrants' psychosocial adaption with the former more significant. In the translation of adaptive psychology to adaptive behavior, the attitude orientation and psychological cognition of migrants are critical. The duration or degree of the adaptive process …

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Multiple Faults Identification Of Three-Level Inverter, Yanxia Shen, Wu Juan, Zhipu Zhao, Zhicheng Ji Jun 2020

Multiple Faults Identification Of Three-Level Inverter, Yanxia Shen, Wu Juan, Zhipu Zhao, Zhicheng Ji

Journal of System Simulation

Abstract: A three-level neutral point clamped (NPC) inverter was taken as an example, phase current and bridge voltage in the fault states of single switch open and several switches open at the same time were analyzed, and a method based on reconstructive phase space (RPS) and wavelet packet analysis was proposed to identify three-level inverter faults. Based on RPS method, totally different reconstructed current trajectories were obtained, which showed the features of the inverter under different fault conditions. With the help of image processing technology, all kinds of faults with different phase currents were identified. The wavelet packet analysis was …

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Simulation Of Joint Power Control Routing Algorithm For Interference And Energy Consumption In Crahns, Zhufang Kuang, Zhigang Chen Jun 2020

Simulation Of Joint Power Control Routing Algorithm For Interference And Energy Consumption In Crahns, Zhufang Kuang, Zhigang Chen

Journal of System Simulation

Abstract: Problems of interference power to primary user by secondary userand the secondary user's running out of energy under underlay spectrum access model in cognitive radio ad hoc networks (CRAHNs) were investigated. Joint power control, routing and spectrum (channel) allocation algorithm (PRSA) based on particle swarm optimization were proposed. The goal of PRSA was to minimize interference power to primary user and prolong lifetime of CRAHNs. Particle encoding, particle initialization, fitness function, particle flight were included in PRSA. An Adjacency matrix with two-tuples containing allocated channel and power level was designed, and three operation rules for particle were redefined. …

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Improved Design Scheme And Simulation Analysis Of Non-Valve Controlled Hydraulic Impact System, Liu Zhong, Zou Yu, Zhang Kai, Zhao Fei, Junjun Liu Jun 2020

Improved Design Scheme And Simulation Analysis Of Non-Valve Controlled Hydraulic Impact System, Liu Zhong, Zou Yu, Zhang Kai, Zhao Fei, Junjun Liu

Journal of System Simulation

Abstract: Due to valve port commutation of traditional hydraulic impact system caused valve leakage. For the above shortcomings, an improved structure principle of the new type of non-valve controlled hydraulic impact system was proposed establishing dynamic equations of impact system andconducting simulation analysis based on AMESim. Due to the simulation results which was inconsistent with design goal, two improvement schemes were proposed adding throttle device and controlling inlet and outlet circuit. The simulation results suggest that the working performance of impact system has been improved by adding throttle device, and its efficiency has been increased from 11.8% to 18.3% …

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Study Of Model Predictive Control Of Pwm Voltage Source Converterwithout Ac Electromotive Force Sensor, Li Hui, Li Zhi, Zhang Jin, Hanmei Peng Jun 2020

Study Of Model Predictive Control Of Pwm Voltage Source Converterwithout Ac Electromotive Force Sensor, Li Hui, Li Zhi, Zhang Jin, Hanmei Peng

Journal of System Simulation

Abstract: The traditional model-predictive-control (MPC), applied to three-phase converter, requires to use AC electromotive force sensor, and then it reduces the system reliability. A three-phase converter model predictive control without AC electromotive force sensor was proposed, and the virtual flux observer was constructed by DC bus voltage, switching signal and AC current. On this basis, a mathematical model of three-phase converter model predictive control quadratic programming (QP-MPC) based on virtual flux oriented was established. Using quadratic programming algorithm, the system can quickly calculate the optimal change, minimize the objective function, and obtain the optimal switch control signal, so as to …

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Under-Determined Blind Source Separation Anti-Collision Algorithm For Rfid Based On Hamming Weight Grouping, Yungang Jin, Xiaohong Zhang, Qiuli Wang Jun 2020

Under-Determined Blind Source Separation Anti-Collision Algorithm For Rfid Based On Hamming Weight Grouping, Yungang Jin, Xiaohong Zhang, Qiuli Wang

Journal of System Simulation

Abstract: The results of the algorithm ofunder-determined blind source separation RFID (Radio Frequency IDentification) system become worse or even lead to the degradation of overall system performancewith the large increase in the number of tags. Anovel parallelizable identification anti-collision algorithm based on constrained non negative matrix factorization (NMF) and Hamming weight grouping technology was proposed. The tag groupings were made by calculating the Hamming weight of the tag's front M bits, which were within the reader identification range. Each group was identified by the RFID reader according to the grouping sequence. Simulation results show that when the antenna number is …

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Inertia Effect In Dynamic Tensile Tests Of Concrete-Like Materials, Zhang Shu, Yubin Lu, Dongmei Zhao, Chen Xing Jun 2020

Inertia Effect In Dynamic Tensile Tests Of Concrete-Like Materials, Zhang Shu, Yubin Lu, Dongmei Zhao, Chen Xing

Journal of System Simulation

Abstract: The different understanding on the influential degree of the inertial effect does exist among researchers, and it has not been uniformly defined in dynamic tensile tests. The finite element numerical simulation method was employed to analyze the three typical dynamic tensile tests, without considering the real strain-rate effect in these models, where a constitutive model only considered the influence of hydrostatic pressure was used for modeling the specimen in these models. It is found that the dynamic tensile strength of concrete specimens in the three models mentioned is strengthened with the increase of loading strain-rate, owing to the …

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Fluid Flow, Heat And Mass Transfer In Hot Dip Galvanizing Bath, Shouqun Sun, Zhongshuang Wei, Huayang Lu Jun 2020

Fluid Flow, Heat And Mass Transfer In Hot Dip Galvanizing Bath, Shouqun Sun, Zhongshuang Wei, Huayang Lu

Journal of System Simulation

Abstract: Zinc dross is produced inevitably as a metallurgical phenomenon of continuous hot galvanizing process, and the quality of galvanizing is affected. The phenomenon is closely related to the physical field of molten zinc and more surface defects are easily produced if the zinc dross removal process is improperly handled. By constructing a three-dimensional viscous standard k-ε two equation turbulence model, the fluid flow, heat and mass transfer law and the distribution regularities of flow vortex were obtained under the specific initial conditions and boundary conditions. The simulation results of the observation points are basically in agreement with the experimental …

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Rtds Simulation Of Quasi-Proportional Resonant Control Of Statcom Under High Voltage, Zhang Yang, Xiaopin Yang Jun 2020

Rtds Simulation Of Quasi-Proportional Resonant Control Of Statcom Under High Voltage, Zhang Yang, Xiaopin Yang

Journal of System Simulation

Abstract: ±100 MVar high voltage static synchronous compensator (STATCOM) device is used for high voltage DC transmission which needs higher reliability. Faster response for its control system to deal with metal ground fault and other situations is required. Direct Current Control (DCC) can be used for these situations. Quasi- Proportional Resonant (quasi-PR) controller under DCC was studied and its parameters settings were discussed. The calculation methods of key parameters such as Kp and Kr were explained by mathematical deduction process. The STATCOM under higher voltage in Yunnan-Guangxi Funing transaction station was taken as an example for the calculation …

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Simulation Of Adaptive Dangerous Weather Warning Method Based On Airborne Weather Radar, Wang Lei, Xingang Liu, Wei Ming Jun 2020

Simulation Of Adaptive Dangerous Weather Warning Method Based On Airborne Weather Radar, Wang Lei, Xingang Liu, Wei Ming

Journal of System Simulation

Abstract: A kind of suitable airborne weather radar algorithm for different seasons, latitude and longitude and underlying surface in China was proposed. A simulation model of airborne weather radar for detecting strong storm weather based on the ground-based weather radar data was established. The improved algorithm of region segmentation and TITAN were used to identify strong storms and their characteristic parameters. China was divided into 16 climate characteristic regions (including East China Sea and South China Sea) per the latitude and longitude. The threshold of strong hail storm radar echo characteristic parameters in these areas was obtained, and the dangerous …

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Meteorological Service Federate Design And Realization Based On Hla, Yintian Liu, Xiaodong Wang, Zaikui Wang Jun 2020

Meteorological Service Federate Design And Realization Based On Hla, Yintian Liu, Xiaodong Wang, Zaikui Wang

Journal of System Simulation

Abstract: To increase flight safety and flight experience under special weather phenomena, the diversity and typical cases of special weather conditions should be considered in flight simulation training, the dynamic and successive meteorological data should be studied, and the insufficient of meteorological services should be overcome by comparing with the traditional flight simulator. The meteorological service with the generation model of multiple size of template library for typical special weather, the dynamical deduction model of meteorological data, and the interpolation calculation model of meteorological grid-point data were proposed. The meteorological service federate based on High Level Architecture (HLA) was established. …

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Weld Trajectory Measurement Based On Stripe Type Laser Sensor, Li Lin, Weijie Chen, Yanbiao Zou Jun 2020

Weld Trajectory Measurement Based On Stripe Type Laser Sensor, Li Lin, Weijie Chen, Yanbiao Zou

Journal of System Simulation

Abstract: Teaching and playback are usually used on welding robot to weld a part. To make sure the implementation of this mode, it is needed to locate the part using artificial sport welding in the front process, which could cause location error and make the actual track deviate from the teaching track. A welding track offline detection device using stripe type laser sensor was proposed for solving the problem. The laser sensor was mounted at the end of the robot. The robot moved along the weld trajectory before welding. The information of the weld track section was gotten and the …

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Simulation On Global Demand Information Sharing Value In B2b Supply Chain, Dongbo Hu, Shen Yue, Rudan Heng, Binbin Zhang Jun 2020

Simulation On Global Demand Information Sharing Value In B2b Supply Chain, Dongbo Hu, Shen Yue, Rudan Heng, Binbin Zhang

Journal of System Simulation

Abstract: In B2B e-commerce environment, a multi-agent simulation model based on the supply chain with multi suppliers was established to study the incentive effects of the global demand information sharing on suppliers and the effects of different parameters on these incentive effects. The research results are as follows: Compared with the local demand information sharing, the global demand information sharing can bring significant incentive effect to the supplier. The global demand information sharing is more valuable with the number of selected suppliers getting closer to the number of alternative suppliers, and an optimal number of alternative suppliers do exist. Based …

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Novel Power Control Algorithm For Cognitive Radio Network, Long Min, Juanjuan Lei Jun 2020

Novel Power Control Algorithm For Cognitive Radio Network, Long Min, Juanjuan Lei

Journal of System Simulation

Abstract: For the problems of near-far effect, large path loss, and stability of algorithm, etc., in the cognitive radio, a new power control algorithm was proposed. Utility function was improved effectively, where punishment factors, such as, link quality and the interference capacity limit of the primary users (PUs) were considered. Signal-to-interference radio (SINR) of cognitive users (CUs) was controlled above the minimum threshold, and the interference value of the CUs was controlled below the capacity tolerance of PUs. The existence of Nash equilibrium was given. Simulation results show that the new algorithm has better stability; the loss of path …

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Research On Feedback Compensation Control For Aircraft Electric Antiskid Brake System Based On Il, Gao Jie, Gao Bing, Jianying Liu Jun 2020

Research On Feedback Compensation Control For Aircraft Electric Antiskid Brake System Based On Il, Gao Jie, Gao Bing, Jianying Liu

Journal of System Simulation

Abstract: Safety, efficiency and comfort of aircraft are all determined by antiskid braking system. Because of the problem of inadequate control in the anti-skid braking system, the nonlinear model of the aircraft electric braking system was built by the analysis of aircraft landing process, and the iterative learning algorithm was introduced for reciprocating characteristics of anti-skid control. The groups in different speeds and road conditions were trained using the PD type learning rate. The knowledge base on the relationship among the optimal slip ratio and velocity and road conditions was built. The feed-forward control knowledge system for identifying the different …

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Survey Of Studies On Numerical Simulations Of Optical-Wave Propagation In Atmospheric Turbulence, Bin Ren, Chunyi Chen, Huamin Yang Jun 2020

Survey Of Studies On Numerical Simulations Of Optical-Wave Propagation In Atmospheric Turbulence, Bin Ren, Chunyi Chen, Huamin Yang

Journal of System Simulation

Abstract: The complicated random behavior of atmospheric turbulence makes it difficult to verify the theories of optical-wave propagation in atmospheric turbulence by conducting experimental measurements. The parameters used in numerical simulations can be easily controlled; therefore numerical simulations have been used as another important tool to investigate the optical-wave propagation in atmospheric turbulence. Based on the existing literature, both the theoretical models and numerical generating methods for random phase screens of atmospheric turbulence are surveyed, and the spatial sampling constraints for numerical simulations of optical propagation in atmospheric turbulence were summarized. By comprehending the existing results, it has been pointed …

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Genetic Algorithm For Solving Multi-Objective Dynamic Flexible Job Shop Scheduling, Wang Chun, Zhang Ming, Zhicheng Ji, Wang Yan Jun 2020

Genetic Algorithm For Solving Multi-Objective Dynamic Flexible Job Shop Scheduling, Wang Chun, Zhang Ming, Zhicheng Ji, Wang Yan

Journal of System Simulation

Abstract: To solve the scheduling problem of mold workshop in a toy factory with dynamic and flexible features, a mathematical model was established by introducing virtual operation and virtual working hours. Based on the strategies of periodic scheduling combined with dynamic event scheduling as well as the rolling window scheduling operation technology, dynamic scheduling was transformed into several continuous static scheduling windows, under which multi-objective genetic algorithm was used to solve the model. The priority of operation scheduling was given in different dynamic events. In addition, the encoding and anti-encoding of chromosome's operation sequence were made based on the proposed …

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Fast Tree Modeling Method Based On Simple Freehand Sketch, Ma Ling, Xiaoping Liu, Xiaoping Liu Jun 2020

Fast Tree Modeling Method Based On Simple Freehand Sketch, Ma Ling, Xiaoping Liu, Xiaoping Liu

Journal of System Simulation

Abstract: Aiming at problems such as complicated process and professional knowledge requirements in tree modeling, a quick tree modeling method for non-experts was proposed, combining branch library with simple sketch to make non-experts create tree model quickly. The method preprocessed the sketch to eliminate noise and error points and identify the strokes, the trunk and branch were reconstructed, child three-dimensional profile was built through the two-dimensional canopy profile, under the constraint of the child profile, suitable branches from library and insert were extracted into the branches, consequently the whole tree model was completed. Experimental results show that this method …

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Improved Particle Swarm Optimization Based On Lévy Flights, Rongyu Li, Wang Ying Jun 2020

Improved Particle Swarm Optimization Based On Lévy Flights, Rongyu Li, Wang Ying

Journal of System Simulation

Abstract: The particle swarm optimization (PSO) has some demerits, such as relapsing into local extremum, slow convergence velocity and low convergence precision in the late evolutionary. The Lévy particle swarm optimization (Lévy PSO) was proposed. In the particle position updating formula, Lévy PSO eliminated the impact of speed on the convergence rate, and used Levy flight to change the direction of particle positions movement to prevent particles getting into local optimum value, and then using greedy strategy to update the evaluation and choose the best solution to obtain the global optimum. The experimental results show that Lévy PSO can effectively …

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