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2019

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Research On Mechanical Configuration Of Automatic Container Terminals Based On Simulation Optimization Method, Shaozheng Yu, Dongshi Sun, Chen Jing, Yongchao Li Dec 2019

Research On Mechanical Configuration Of Automatic Container Terminals Based On Simulation Optimization Method, Shaozheng Yu, Dongshi Sun, Chen Jing, Yongchao Li

Journal of System Simulation

Abstract: In the study of mechanical configuration problem of automated container terminal, a system simulation model based on discrete event simulation is constructed. The key parameters and interference factors that affect the performance of the system are fully considered in the model and a mechanical scheduling algorithm interface to ensure the effectiveness of the simulation model is designed. On the premise of ensuring the reliability of the container terminal system, a cycle optimization method of mechanical configuration scheme is proposed to minimize the cost. An example is given to solve the mechanical configuration scheme of an automatic container terminal. …

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Research On The Simulation Technology For Multi-Aerocraft Cooperative Guidance, Li Jing, Han Jian, Zhang Qing Dec 2019

Research On The Simulation Technology For Multi-Aerocraft Cooperative Guidance, Li Jing, Han Jian, Zhang Qing

Journal of System Simulation

Abstract: The formal system of multi- aerocraft cooperative simulation system is identified as the discrete event system & different equation system specifications (DEV&DESS) through the analysis of the composition and running mechanism. The running control problem of cooperative simulation system is transformed into simulation control problem of a specific DEV&DESS system. A dynamic operation control method for cooperative guidance simulation system based on coordinator is proposed, and this method is validated by real-time mathematical simulation experiments.

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An Lstm-Based Motion Recognition Method For Power Operation And Maintenance, Peizhen Liu, Yuxiang Jia, Shihong Xia Dec 2019

An Lstm-Based Motion Recognition Method For Power Operation And Maintenance, Peizhen Liu, Yuxiang Jia, Shihong Xia

Journal of System Simulation

Abstract: The security of power operation and maintenance has always been a subject of great social concern. In order to avoid serious consequences caused by the fault of staffs, a motion recognition method for power operation and maintenance jobs based on LSTM (Long Short-Term Memory) is proposed, which covers the whole process from data collection, data processing to motion classification and recognition, then it can recognise and supervise the behavior of staffs who are at work. In addition, a simulation experiment is conducted between the deep learning algorithm LSTM and the traditional machine learning algorithm KNN based on the newly …

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Design Of Feedback Linearization Nonlinear Controller For Asynchronous Motor Power Consumption Efficiency, Li Rui, Yingnian Wu Dec 2019

Design Of Feedback Linearization Nonlinear Controller For Asynchronous Motor Power Consumption Efficiency, Li Rui, Yingnian Wu

Journal of System Simulation

Abstract: In order to realize precise feedback linearization and optimal control of motor power consumption for MIMO nonlinear affine system, we build the model of induction motor within which dynamic power loss factor is included. Based on the differential geometry theory, a nonlinear optimization model of the controller is designed for this model to control the asynchronous motor outputs accurately and enhance the power efficiency. This paper presents an optimal control law for multiple inputs multiple outputs affine nonlinear system and the detailed design steps are given combined with examples for multiple outputs tracking problem. The simulation results show that …

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Violin Bow-Hand Prosthetic, Jonathan Smith, Jonathon Azziz, Shawn Pavey Dec 2019

Violin Bow-Hand Prosthetic, Jonathan Smith, Jonathon Azziz, Shawn Pavey

Mechanical Engineering Design Project Class

The violin bow hand prosthetic was designed for a young violin player seeking to upgrade the functionality of his current violin prosthetic device. His current device is rigid, forcing him to play mostly with his shoulder. Since the strength of his wrist was unknown, we designed a prosthetic with enough brace flexibility to enable the user to control the bow motion with his own wrist. We also added an axis of rotation and spring mechanism to supplement this motion and provide him the equivalence of fine finger adjustments. The full design process of the prosthetic is documented in this report, …

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Schrödinger Evolution Of Superoscillations With Δ - And Δ′ -Potentials, Yakir Aharonov, Jussi Behrndt, Fabrizio Colombo, Peter Schlosser Dec 2019

Schrödinger Evolution Of Superoscillations With Δ - And Δ′ -Potentials, Yakir Aharonov, Jussi Behrndt, Fabrizio Colombo, Peter Schlosser

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this paper, we study the time persistence of superoscillations as the initial data of the time-dependent Schrödinger equation with δ- and δ′-potentials. It is shown that the sequence of solutions converges uniformly on compact sets, whenever the initial data converge in the topology of the entire function space A1(C). Convolution operators acting in this space are our main tool. In particular, a general result about the existence of such operators is proven. Moreover, we provide an explicit formula as well as the large time asymptotics for the time evolution of a plane wave under δ- and δ′-potentials.

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A Modular Open-Source Pre-Processing Tool For Finite Element Simulations Of Additive Manufacturing Processes, William Furr Dec 2019

A Modular Open-Source Pre-Processing Tool For Finite Element Simulations Of Additive Manufacturing Processes, William Furr

Theses and Dissertations

Additive manufacturing has shown the ability to produce highly complex geometries that are not easily manufactured through traditional means. However, the implications of building these complex geometries regarding thermal history requires more attention. AM process simulations have proven to be computationally expensive and require large amounts of pre-processing to execute. This thesis will start with a review of additive manufacturing along with current modeling efforts. Then, the development of a pre-processing tool for finite element simulations of these processes is presented. It is shown that the pre-processing tool significantly decreases the total time-to-simulation by removing manual steps. Finally, a study …

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An Outdoor Professional Development Model In The Era Of The Next Generation Science Standards, Shana Lee Dec 2019

An Outdoor Professional Development Model In The Era Of The Next Generation Science Standards, Shana Lee

Theses and Dissertations

Experiential, outdoor education supports improvement in students’ problem-solving skills; collaboration and communication skills; and enjoyment in learning in the outdoors. Outdoor instruction is becoming increasingly underutilized. A residential environmental education center, located in Tennessee has conducted professional development programs in effort to increase teacher implementation of instruction in outdoor spaces. This institute revealed concern for low implementation rates to past professional development opportunities. Their newly designed, long-term professional development explored teacher’s perceived challenges and needs, then combined effective experiential pedagogy in outdoor spaces with pre-established communities of support from the participating schools in effort to contribute to experiential, outdoor instruction …

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Developing An Organizational Decision Making Model: The Impact Of Organizational Structures, Decision Types, And The Social Network, John Huggins Dec 2019

Developing An Organizational Decision Making Model: The Impact Of Organizational Structures, Decision Types, And The Social Network, John Huggins

Theses and Dissertations

Organizational decision making can be seen as a complex process due to the fact that decisions across organizational levels are generally interdependent, and have effects ranging from immediate to long-lasting. Reviewing decision making mathematical and process models, decision making is fundamentally characterized by multiple decision making steps from encountering a problem to determining a course of action. The first objective of this dissertation was the determination of the decision making model that a certain type of organization uses, and the establishment of a foundation for an organizational decision model framework. Decision making can be classified into three decision types: strategic, …

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Toward Early Detection Of Pancreatic Cancer: An Evidence-Based Approach, Omid Sharagi Dec 2019

Toward Early Detection Of Pancreatic Cancer: An Evidence-Based Approach, Omid Sharagi

Master's Projects

This study observes how an evidential reasoning approach can be used as a diagnostic tool for early detection of pancreatic cancer. The evidential reasoning model combines the output of a linear Support Vector Classifier (SVC) with factors such as smoking history, health history, biopsy location, NGS technology used, and more to predict the likelihood of the disease. The SVC was trained using genomic data of pancreatic cancer patients derived from the National Cancer Institute (NIH) Genomic Data Commons (GDC). To test the evidential reasoning model, a variety of synthetic data was compiled to test the impact of combinations of different …

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A Second Language Task Based Learning Experience For Children, Sofia L. Alfieri Dec 2019

A Second Language Task Based Learning Experience For Children, Sofia L. Alfieri

Electronic Theses & Dissertations

The study was designed to investigate the implementation phase of a Task Based Learning approach for teaching English as a Second Language to an intact sample of 25 children, six to seven years of age and whose first language in Asuncion, Paraguay was Spanish. Most of the theory behind Task Based Learning (TBL) was accomplished with adolescents and adults. The present researcher found that many of the tasks researched were either not developmentally appropriate or likely needed significant adaptations. Therefore, tasks were developed and adapted to be likely appropriate for children 6 to7 years of age. Findings revealed that adaptations …

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Equivalence-Based Instruction To Teach Single-Subject Designs In Higher Education, Griffin Decuir Williams Dec 2019

Equivalence-Based Instruction To Teach Single-Subject Designs In Higher Education, Griffin Decuir Williams

Electronic Theses & Dissertations

With the increasing prevalence of online courses and instruction, advanced methods to teach technical concepts for students in higher education are of value. Equivalence-Based Instruction (EBI) is an effective, efficient, and empirically validated teaching methodology. This study developed a match-to-sample EBI protocol embedded in CANVAS to teach four common single-subject designs to graduate students. Results were compared between an equivalence group receiving a reduced-intensity EBI protocol and a group receiving a traditional video lecture to serve as the control. The ability of the participants to generalize the trained relations to novel stimuli was also evaluated. Results indicate that the EBI …

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Research On Intelligent Clustering Algorithm For Complex Water Wireless Network Surveillance, Hua Xiang, Hongtao Liang, Zhaoxin Dong, Wang Zhao, Hongjuan Yao, Baohua Li, Bingqing Jiang Dec 2019

Research On Intelligent Clustering Algorithm For Complex Water Wireless Network Surveillance, Hua Xiang, Hongtao Liang, Zhaoxin Dong, Wang Zhao, Hongjuan Yao, Baohua Li, Bingqing Jiang

Journal of System Simulation

Abstract: The clustering of irregular networks will cause load imbalance, which results in the phenomenon of “energy hot zone”. Aiming at the unreasonable topology of irregular network clustering, an intelligent clustering algorithm based on genetic strategy is proposed for the wireless network surveillance of complex water system. An irregular complex water topology model and an energy consumption model are built, and a genetic clustering strategy is designed via the principle of minimum energy consumption. The P matrix coding method is given, which avoids the squared increment of data calculation. Simultaneously, an adaptive genetic operator and a fuzzy modified operator are …

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Moving Object Detection Based On Deep Convolutional Neural Network, Yuqiu Lu, Jinyu Sun, Shiwei Ma Dec 2019

Moving Object Detection Based On Deep Convolutional Neural Network, Yuqiu Lu, Jinyu Sun, Shiwei Ma

Journal of System Simulation

Abstract: A deep convolution neural network MONet is designed for the intermittent motion problem in moving objects detection. In the absence of training data sets, a synthetic dataset GoChairs is generated by affine transformation, and on this basis the network training and testing are performed. The results show that the trained MONet can effectively detect the moving objects based on the correspondence between the pixels. The traditional datasets CDnet and I2R are also tested to verify the generalization performance of the network. In addition, MONet is compared qualitatively and quantitatively with classical methods for the intermittent motion problem of …

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3d Shape Deformation Simulation Algorithm Based On Haptics, Binbin Qi, Xuefang Zhu, Lipeng Fan Dec 2019

3d Shape Deformation Simulation Algorithm Based On Haptics, Binbin Qi, Xuefang Zhu, Lipeng Fan

Journal of System Simulation

Abstract: Shape deformation is widely used in virtual reality, system simulation, computer animation and other graphics applications. Few people pay attention to introducing haptic interaction into 3D model deformation. We provide a haptic interactive framework by introducing haptic interaction into shape editing field. Based on the above haptic interactive framework, we propose a 3D model deformation simulation algorithm based on haptics. In order to realize the shape deformation, this algorithm needs to involve three parts: grid hierarchical structure, local mass-spring model and the dynamic shape deformation. Experimental results show that this algorithm has good stability and strong robustness, and the …

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Intelligent Manufacturing Plan Management Based On Digital Twins, Yingying Xiao, Wang Mei, Liqin Guo, Xing Chi, Changhui Zhuang Dec 2019

Intelligent Manufacturing Plan Management Based On Digital Twins, Yingying Xiao, Wang Mei, Liqin Guo, Xing Chi, Changhui Zhuang

Journal of System Simulation

Abstract: For the multi-variety and small-batch manufacturing mode, the planning management system cannot be timely automatically adjusted according to uncertain factors. This paper proposes an intelligent manufacturing plan management system based on factory digital twins. The plan management PDCA business process model is established. In addition, the processing logic model and constraints of the periodic static scheduling model and the dynamic emergency scheduling model are proposed. Based on the planning management case of hybrid assembly of two types of aerospace complex products, it is verified that the management model proposed in this paper can support the intelligent dynamic adjustment of …

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A Cloud Service Composition Optimization Based On Hnn, Huili Zhang, Zhihe Li Dec 2019

A Cloud Service Composition Optimization Based On Hnn, Huili Zhang, Zhihe Li

Journal of System Simulation

Abstract: With the rapid development of Cloud service application, how to effectively optimize the composition of Cloud services on cloud platform and improve the overall performance of cloud platform system have become an urgent research issue. In order to improve the efficiency of Cloud services, a combined optimization model based on Hopfield neural network is proposed. The problem of Cloud services is modeled. The problem is expressed as Hopfield Neural Network energy model for optimization, and a PSO group algorithm with Cauchy disturbance is designed to improve the Hopfield model. The experimental comparison shows that the method can improve …

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Modeling And Simulation Of Complex Equipment Health Management System Based On Cloud Computing, Tianrui Zhang, Chuansheng Qu, Baoku Wu, Jianan Xu Dec 2019

Modeling And Simulation Of Complex Equipment Health Management System Based On Cloud Computing, Tianrui Zhang, Chuansheng Qu, Baoku Wu, Jianan Xu

Journal of System Simulation

Abstract: For complex equipment operation safely, the health management problems of complex equipment life cycle is analyzed. In order to realize remote service, complex equipment health management mode based on cloud computing is proposed. Aiming at the accuracy problem in the process of extracting and recognizing complex equipment characteristic data, the feature knowledge acquisition method based on ontology is researched, and the expression and acquisition algorithm of state characteristic knowledge is proposed. A task sequencing algorithm faults based on fuzzy comprehensive evaluation method is proposed, an appropriate task assignment model is selected for scheduling health management technicians. …

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Agent Based Modeling And Simulation Analysis Of Low-Orbit Early-Warning Satellites, Liu Wen, Xiaolu Wang, Hongsheng Wang, Zhang Heng, Changqing Wang Dec 2019

Agent Based Modeling And Simulation Analysis Of Low-Orbit Early-Warning Satellites, Liu Wen, Xiaolu Wang, Hongsheng Wang, Zhang Heng, Changqing Wang

Journal of System Simulation

Abstract: Low-Orbit Early-Warning Satellite has accurate midcourse ballistic missile tracking and surveillance capability. The paper takes Space Tracking and Surveillance System’s function and construction as the research subject. System model is constructed based on Agent method. The possible constellation configurations of STSS are analyzed considering the coverage performance,and the detection capability of ballistic missile target is simulated and analyzed. Simulation analysis of target detection is carried out. The result shows that STSS can effectively detect a certain number of targets, but detecting capability is affected severely by solar illumination.

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Simulation Of Vehicle Startup Delay At Green Light And Its Direct And Chain-Reaction Impact On Traffic Flow, Longxi Luo, Lijun Xie, Jianping Wu, Xu Ming Dec 2019

Simulation Of Vehicle Startup Delay At Green Light And Its Direct And Chain-Reaction Impact On Traffic Flow, Longxi Luo, Lijun Xie, Jianping Wu, Xu Ming

Journal of System Simulation

Abstract: In current traffic simulations, it is implicitly assumed vehicles are driven by ideal drivers. Therefore, simulated vehicles make the most reasonable decisions such as moving out immediately when traffic lights turn green, resulting in a gap between simulations and real traffics. Research shows that drivers, including those who follow the rules, show a delay in starting-up their vehicles at the green light. The vehicle startup delay (SUD) is even more significant for drivers by things such as cell phones during waiting. However, the SUD has rarely been considered in simulations. The SUD is simulated to study its impacts on …

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Fault Prediction Of Satellite Attitude Control System Based On Neural Network, Xiaofan Meng, Song Hua Dec 2019

Fault Prediction Of Satellite Attitude Control System Based On Neural Network, Xiaofan Meng, Song Hua

Journal of System Simulation

Abstract: A new method based on BP neural network(BPNN), wavelet neural network(WNN) and wavelet decomposition-LSTM(wLSTM) network is proposed for predicting faults in the satellite attitude control system. Normal satellite attitude data is used to train BPNN which is used as the standard model of satellite attitude control system. The real-time attitude residuals is obtained by subtracting the BPNN output attitude angle from the real-time data of satellite attitude. The time series of the residuals are used to build WNN and wLSTM models to predict the faults of satellite attitude control system. A conclusion is given according to comparing the …

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Design Of Combat Simulation And Visualization System Of Hypersonic Vehicle, Yu Ying, Weidong Liang, Xiujuan Zhu, Jianlin Wang, Wang Ling Dec 2019

Design Of Combat Simulation And Visualization System Of Hypersonic Vehicle, Yu Ying, Weidong Liang, Xiujuan Zhu, Jianlin Wang, Wang Ling

Journal of System Simulation

Abstract: Based on the thought of combat simulation, the system of combat simulation and visualization is designed to show the typical combat mode and the characteristics of near space vehicles. Taking the aircraft attacking a fixed target as an example, the formulation of combat plan, the deployment of forces and the design of combat process of both sides are realized. On the one hand, a combat simulation platform which covers various combat modes of attack and defense is established. On the other hand, the whole process of combat confrontation of hypersonic vehicles is presented, driven by the real-time simulation data. …

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Multi-Sensor Data Fusion With Network Delays And Correlated Noises, Shankai Zhang, Zhu Cui, Su Zhong, Dai Juan Dec 2019

Multi-Sensor Data Fusion With Network Delays And Correlated Noises, Shankai Zhang, Zhu Cui, Su Zhong, Dai Juan

Journal of System Simulation

Abstract: This paper focuses on the state estimation for multi-sensor system with network delays and correlated noises. An orthogonal transformation method is applied to remove the correlations between different noises. For the problem of packet delays due to the unreliable network, a buffer with certain length is introduced to store the measurements, and the measurements are reordered using a timestamp in the buffer. Based on that, a novel sequential data fusion algorithm is proposed, by which the influence of the noise correlation and packet delays can be weakened effectively. Compared with the traditional sequential fusion method, the proposed algorithm has …

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Pedestrian Navigation Method Based On Uwb And Sins, Yang Yang, Li Qing Dec 2019

Pedestrian Navigation Method Based On Uwb And Sins, Yang Yang, Li Qing

Journal of System Simulation

Abstract: In view of the problem that the inertial navigation error is accumulating with time and UWB indoor is hard to continue tracking problems in complex environment, an extended Kalman filter (EKF) fusing UWB and sins pedestrian navigation is proposed.The zero speed correction algorithm is used to trigger EKF at zero speed. The sins is corrected by the velocity error measurement provided by sins and the position error measurement provided by UWB restraining error accumulation.When UWB signal is interrupted, the position of UWB output without interruption is taken as the starting position. The experiment results of SINS autonomous navigation …

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Research On Uncertainty Measurement Method Of Aircraft Hwil System, Huapin Geng, Jiahui Tong, Hongtao Ma Dec 2019

Research On Uncertainty Measurement Method Of Aircraft Hwil System, Huapin Geng, Jiahui Tong, Hongtao Ma

Journal of System Simulation

Abstract: Uncertainty is the inherent attribute of simulation system, causing the expected results inconformity with the real results, even influencing the robustness and reliability of system. Based on the analysis of the system uncertainty characteristics, the analysis framework of HWIL system uncertainty measurement is proposed. Three kinds of the uncertainty measurement methods based on the uncertainty type and the compound and weighting are researched on aircraft HWIL System. The typical uncertainty measurement methods are applied based on some aircraft HWIL system and the result proves that the method is efficient.

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Fault-Tolerant Method And Simulation Of Heterogeneous Multi-Core Processor Based On Speculative Mechanism, Shigan Yu, Zhimin Tang, Xiaochun Ye, Dongrui Fan Dec 2019

Fault-Tolerant Method And Simulation Of Heterogeneous Multi-Core Processor Based On Speculative Mechanism, Shigan Yu, Zhimin Tang, Xiaochun Ye, Dongrui Fan

Journal of System Simulation

Abstract: Heterogeneous multicore is one of the important branches of processors,but they are still faced with frequent transient failures. TMR(Triple mode redundancy) is the main method to solve transient faults, which has the characteristics of low efficiency and high power consumption, a high-performance Fault-Tolerant Scheduling Algorithm with Speculative mechanism(FTSAS) is proposed. Each heterogeneous core can execute tasks independently, the state values of the first completed core are recorded, and the first completed core continues to perform the next task with forward speculative method. The results are compared by backward core, the majority consensus principle is adopted to ensure the reliability …

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Lstm Model For Trajectory Design Of Missile-Borne Bfsar Imaging Guidance, Bohao Li, Yunjie Wu Dec 2019

Lstm Model For Trajectory Design Of Missile-Borne Bfsar Imaging Guidance, Bohao Li, Yunjie Wu

Journal of System Simulation

Abstract: In the multi-platform path planning of multi-missile cooperative guidance algorithm used for missile-borne Bi-static Forward-looking Synthetic Aperture Radar (BFSAR) imaging, it is necessary to plan and adjust the transmitter trajectory according to the space state of the receiver and the path constraints between the receiver and the transmitter.An effective LSTM model is constructed to study and train the trajectory path generated by the existing algorithms, and the direct mapping relationship between the receiver space state, path constraint and the trajectory of the transmitter is obtained. The simulation results not only show that LSTM is feasible in multi-missile path …

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Energy Efficiency Data Mining And Scheduling Optimization Of Discrete Workshop, Yugu Lin, Wang Yan Dec 2019

Energy Efficiency Data Mining And Scheduling Optimization Of Discrete Workshop, Yugu Lin, Wang Yan

Journal of System Simulation

Abstract: This paper addresses the optimization of energy consumption in discrete workshops and establishes the energy efficiency optimization model of discrete workshops. The relationship between data mining and knowledge discovery is established. Through scheduling data preprocessing and C4.5 decision tree learning algorithm, the discovery of scheduling knowledge is realized. Energy efficiency optimization calculation is achieved in discrete workshops by the combination of scheduling knowledge and improved differential evolution algorithm (IDE). By comparing with TLBO, GA and PSO, the feasibility of IDE algorithm is verified.

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Research On Social Network Inference Method Based On Observation Data, Hailiang Chen, Bin Chen, Yuan Peng, Dong Jian, Chuan Ai Dec 2019

Research On Social Network Inference Method Based On Observation Data, Hailiang Chen, Bin Chen, Yuan Peng, Dong Jian, Chuan Ai

Journal of System Simulation

Abstract: Internet technology and online social networks have developed rapidly, which enables people to randomly express their opinions, ideas, emotional exchanges and economic exchanges. Inferring social networks is made possible through the observation data exchanged by people on the Internet. Through the analysis of ConNIe (Convex Network Inference) algorithm, this paper researches the effects of sparse parameter, propagation time distribution model and its parameters on the inference results of the algorithm. According to the analysis, a social network inference framework based on ConNIe algorithm is proposed. Combining the perceptron and particle swarm optimization algorithm, the ConNIe algorithm inference becomes a …

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Exploration Of Soldier Morale Using Multi-Mode Simulation Approach, Yongsheng Zhang, Zhengxiang Xiong Dec 2019

Exploration Of Soldier Morale Using Multi-Mode Simulation Approach, Yongsheng Zhang, Zhengxiang Xiong

Journal of System Simulation

Abstract: Soldier morale is a complex social construction influenced by factors at multiple levels and integrates many research domains. This research seeks to explore, model, and simulate soldier morale at multiple levels of analysis. Microcosmically Agent-Based Modeling method is used to reflect the interaction among fighters and the course of affecting morale,Macrocosmically SD method is used to reflect the influence of the tactical psychology on morale and the whole war in the counter-combat process. The developed sample case scenario pertained to US security efforts against insurgency in Afghanistan in 2007. The scenario includes representation of the patrol base operations serving …

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