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Novel Models and Algorithms of Load Balancing for Variable-structured Collaborative Simulation under HLA/RTI

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Chinese Journal of Mechanical Engineering 2013年第4期26卷 629-640页

作者： YUE Yingchao FAN Wenhui XIAO Tianyuan MA Cheng State cims Engineering Research center Tsinghua University

High level architecture(HLA) is the open standard in the collaborative simulation field. Scholars have been paying close attention to theoretical research on and engineering applications of collaborative simulation based on HLA/RTI, which extends HLA in various aspects like functionality and efficiency. However, related study on the load balancing problem of HLA collaborative simulation is insufficient. Without load balancing, collaborative simulation under HLA/RTI may encounter performance reduction or even fatal errors. In this paper, load balancing is further divided into static problems and dynamic problems. A multi-objective model is established and the randomness of model parameters is taken into consideration for static load balancing, which makes the model more credible. The Monte Carlo based optimization algorithm(MCOA) is excogitated to gain static load balance. For dynamic load balancing, a new type of dynamic load balancing problem is put forward with regards to the variable-structured collaborative simulation under HLA/RTI. In order to minimize the influence against the running collaborative simulation, the ordinal optimization based algorithm(OOA) is devised to shorten the optimization time. Furthermore, the two algorithms are adopted in simulation experiments of different scenarios, which demonstrate their effectiveness and efficiency. An engineering experiment about collaborative simulation under HLA/RTI of high speed electricity multiple units(EMU) is also conducted to indentify credibility of the proposed models and supportive utility of MCOA and OOA to practical engineering systems. The proposed research ensures compatibility of traditional HLA, enhances the ability for assigning simulation loads onto computing units both statically and dynamically, improves the performance of collaborative simulation system and makes full use of the hardware resources.

关键词： static load balancing dynamic load balancing variable-structure collaborative simulation under HLA/RTI multi-objective optimization ordinal optimization

Synergic Motion Trajectory Planning for Airplane Docking Based on6PURU Parallel Mechanism

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Tsinghua Science and Technology 2015年第2期20卷 188-199页

作者： Hui Li Linxuan Zhang Tianyuan Xiao Jietao Dong State cims Engineering Research center at Tsinghua University

Motion planning issues encountered in assembling airplanes by employing the 6PURU parallel mechanism are analyzed in this paper. A sine curve of the change rate of acceleration, which is called as jerk in the following text, is proposed for uniaxial flexible acceleration and deceleration planning based on the optimal time and velocity and acceleration constraints. Compared with other curves, the proposed curve can realize a continuous n-order derivative and the smooth change of the speed and acceleration. The method is computational^y simple and suitable for programming. In addition, a multiaxial coordinated movement scheme is proposed. The motion trajectory is no longer simply split into many single-direction trajectories nor are all single-direction planning trajectories combined directly. The multiaxial coordinated movement scheme aims to achieve synergic movement in multiple directions to ensure smoothness of the movement in the event of a kinematic error when maintaining a stable value. If the movement fails to achieve this goal, driving force mutations will deteriorate the effect of synergic movement. A physical model of the parallel mechanism is developed in simMechanics, and a holistic system model is completed in SIMULINK. The feasibility of the new planning algorithm is simulated and tested, and then, the multiaxial synergic movement planning method is proposed and verified.

关键词： assembly simulation motion trajectory planning parallel mechanism simMechanics

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基于高斯-柯西混合变异的多目标粒子群算法

计算机与数字工程 2024年第6期52卷 1593-1597,1603页

作者：舒一鸣戴毅茹同济大学cims研究中心上海201804

针对MOPSO优化算法在解决复杂的多目标优化问题上收敛表现差,搜索全局能力不足与易于陷入局部最优的缺陷,提出了一种基于高斯-柯西混合变异的多目标粒子群算法(GC-MOPSO)。该算法使用一种混合高斯变异与柯西变异的变异扰动机制来提升粒... 详细信息

针对MOPSO优化算法在解决复杂的多目标优化问题上收敛表现差,搜索全局能力不足与易于陷入局部最优的缺陷,提出了一种基于高斯-柯西混合变异的多目标粒子群算法(GC-MOPSO)。该算法使用一种混合高斯变异与柯西变异的变异扰动机制来提升粒子在局部与全局的搜索能力,在外部档案中采用锦标赛选择机制选取全局最优个体的策略来增加种群的多样性。通过与六项其他算法在反世代距离(IGD)上进行比较,验证了该算法的优势。

关键词：多目标优化粒子群优化算法高斯-柯西变异锦标赛选择

Towards Production and Energy Coupling System Modeling and Simulation for Energy Optimization in the Process Industry

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Journal of Donghua University(English Edition) 2011年第2期28卷 128-133页

作者：戴毅茹王坚 cims Research center Tongji University

The production and energy coupling system is used to mainly present energy flow, material flow, information flow, and their coupling interaction. Through the modeling and simulation of this system, the performance of energy flow can be analyzed and optimized in the process industry. In order to study this system, the component based hybrid Petri net methodology (CpnHPN) is proposed, synthesizing a number of extended Petri net methods and using the concept of energy place, material place, and information place. Through the interface place in CpnHPN, the component based encapsulation is established, which enables the production and energy coupling system to be built, analyzed, and optimized on the multi-level framework. Considering the block and brief simulation for hybrid system, the CpnHPN model is simulated with Simulink/Stateflow. To illustrate the use of the proposed methodology, the application of CpnHPN in the energy optimization of chlorine balance system is provided.

关键词： process industry energy optimization production and energy coupling system Petri net modeling simulation

Research of Web-based Workflow Management System

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High Technology Letters 2001年第1期7卷 55-58页

作者：梁浩 Wu Qidi SHI Junhao cims Research center Tongji University

The state of the art of workflow management techniques in research is introduced. The research and development trends of Workflow Management System (WFMS) are presented. On basis of analysis and comparison of kinds of WFMSs, a WFMS based on Web technology and distributed object management is proposed. Finally, the application of the WFMS in supply chain management is described in detail.

关键词： Workflow management Web technology Supply chain management

GREEDY NON-DOMINATED SORTING IN GENETIC ALGORITHM-ⅡFOR VEHICLE ROUTING PROBLEM IN DISTRIBUTION

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Chinese Journal of Mechanical Engineering 2008年第6期21卷 18-24页

作者： WEI Tian FAN Wenhui XU Huayu National cims Engineering Research center Tsinghua University Beijing 100084 China

Vehicle routing problem in distribution （VRPD） is a widely used type of vehicle routing problem （VRP）, which has been proved as NP-Hard, and it is usually modeled as single objective optimization problem when modeling. For multi-objective optimization model, most researches consider two objectives. A multi-objective mathematical model for VRP is proposed, which considers the number of vehicles used, the length of route and the time arrived at each client. Genetic algorithm is one of the most widely used algorithms to solve VRP. As a type of genetic algorithm （GA）, non-dominated sorting in genetic algorithm-Ⅱ （NSGA-Ⅱ） also suffers from premature convergence and enclosure competition. In order to avoid these kinds of shortage, a greedy NSGA-Ⅱ （GNSGA-Ⅱ） is proposed for VRP problem. Greedy algorithm is implemented in generating the initial population, cross-over and mutation. All these procedures ensure that NSGA-Ⅱ is prevented from premature convergence and refine the performance of NSGA-Ⅱ at each step. In the distribution problem of a distribution center in Michigan, US, the GNSGA-Ⅱ is compared with NSGA-Ⅱ. As a result, the GNSGA-Ⅱ is the most efficient one and can get the most optimized solution to VRP problem. Also, in GNSGA-Ⅱ, premature convergence is better avoided and search efficiency has been improved sharply.

关键词： Greedy non-dominated sorting in genetic algorithm-Ⅱ (GNSGA-Ⅱ) Vehicle routing problem (VRP) Multi-objective optimization

Design and Implementation of Visualized Workflow Modeling System Based on B/S Structure

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Journal of Donghua University(English Edition) 2007年第1期24卷 75-78页

作者：王坚李巍丽 cims Research center Tongji University

According to the necessity of flexible workflow management system, the solution to set up the visualized workflow modelling system based on B/S structure is put forward, which conforms to the relevant specifications of WfMC and the workflow process definition meta-model. The design for system structure is presented in detail, and the key technologies for system implementation are also introduced. Additionally, an example is illustrated to demonstrate the validity of system.

关键词： work flow work flow modeling system XPDL parsing.

基于自适应二次分解与CNN-BiLSTM的超短期风电功率预测

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太阳能学报 2024年第6期45卷 429-435页

作者：马志侠张林鍹巴音塔娜谢明浩张盼盼王馨新疆大学电气工程学院乌鲁木齐830047 清华大学国家计算机集成制造系统工程技术研究中心(cims) 北京100084

为提高风电功率预测精度,提出基于自适应二次模态分解(QMD)、卷积神经网络(CNN)与双向长短期记忆网络(BiLSTM)的超短期风电功率预测模型。针对风电功率的波动性,利用改进的完全自适应噪声集成经验模态分解方法(ICEEMDAN)对风电功率数据... 详细信息

为提高风电功率预测精度,提出基于自适应二次模态分解(QMD)、卷积神经网络(CNN)与双向长短期记忆网络(BiLSTM)的超短期风电功率预测模型。针对风电功率的波动性,利用改进的完全自适应噪声集成经验模态分解方法(ICEEMDAN)对风电功率数据进行分解。引入麻雀搜索算法(SSA)对变分模态分解(VMD)的分解数量与惩罚因子进行优化,使VMD具有自适应性。将ICEEMDAN分解得到的高频分量I_(1)用SSA-VMD进行第二次分解,降低序列不平稳度。同时,构建包含2层池化层的CNN网络进行特征提取与BiLSTM网络的超短期预测模型,最终的风电功率即为各子序列预测结果之和。通过算例分析进行实验表明,所提风电功率预测方法的预测精度优于其他模型,验证了预测模型的优越性。

关键词：卷积神经网络长短期记忆网络变分模态分解风电功率预测二次模态分解麻雀搜索算法

IMPULSIVE CONTROL FOR THE STABILIZATION AND SYNCHRONIZATION OF LUR'E SYSTEMS

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Applied Mathematics and Mechanics(English Edition) 2004年第3期25卷 322-328页

作者：孙继涛吴启迪 Department of Applied Mathematics Tongji University cims Research center Tongji University

An impulsive control scheme of the Lur' e system and several theorems on stability of impulsive control systems was presented,these theorems were then used to find the conditions under which the Lur' e system can be stabilized by using impulsive control with varying impulsive *** parameters of Lur' e system and impulsive control law are given,a theory of impulsive synchronization of two Lur' e system is also presented. A numerical example is used to verify the theoretical result.

关键词： impulsive control stabilization synchronization Lur'e system