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Multi-objective optimization based optimal setting control for industrial double-stream alumina digestion process 被引量:1
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作者 WANG Xiao-li LU Mei-yu +1 位作者 WEI Si-mi XIE Yong-fang 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第1期173-185,共13页
The operation variables,including feed rate of ore slurry,caustic solution and live steams in the double-stream alumina digestion process,determine the product quality,process costs and the environment pollution.Previ... The operation variables,including feed rate of ore slurry,caustic solution and live steams in the double-stream alumina digestion process,determine the product quality,process costs and the environment pollution.Previously,they were set by the technical workers according to the offline analysis results and an empirical formula,which leads to unstable process indices and high consumption frequently.So,a multi-objective optimization model is built to maintain the balance between resource consumptions and process indices by taking technical indices and energy efficiency as objectives,where the key technical indices are predicted based on the digestion kinetics of diaspore.A multi-objective state transition algorithm(MOSTA)is improved to solve the problem,in which a self-adaptive strategy is applied to dynamically adjust the operator factors of the MOSTA and dynamic infeasible threshold is used to handle constraints to enhance searching efficiency and ability of the algorithm.Then a rule based strategy is designed to make the final decision from the Pareto frontiers.The method is integrated into an optimal control system for the industrial digestion process and tested in the actual production.Results show that the proposed method can achieve the technical target while reducing the energy consumption. 展开更多
关键词 double-stream digestion process optimal setting control multi-objective optimization state transition algorithm rule based decision making
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Internet-Based Optimization and Choice of Insert Grooves for Face-Milling
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作者 DONG Li-hua 1, XU Xiao-cun 1, LI Zhen-jia 1, WEI Hua-liang 2 (1. Department of Mechanical Engineering, Harbin University of Science and Technology, Harbin 150080, China 2. Harbin Measuring and Cutting Works, Harbin 150040, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期37-38,共2页
Manufacture is facing more furiously competition in the new century. It tends to be globalized. Rapid response and technology innovation have become the key factor to the success of manufacture enterprise. At present,... Manufacture is facing more furiously competition in the new century. It tends to be globalized. Rapid response and technology innovation have become the key factor to the success of manufacture enterprise. At present, internet-based manufacturing develops rapidly. With the development of engineering material and machining techniques, better cutting properties of metal cutting tools are required. The world is paying more attention to the study of indexable carbide inserts with three-dimensional complex grooves which can affect cutting properties directly and chip-controlling. So the variety and specification of indexable insert develop quickly and the application of insert with three-dimensional complex chip-former becomes wider and wider. Because milling is an interrupted cutting, the process of milling is complicated and the failure of the milling inserts is severe. It is important to choose suitable milling inserts groove for particular machining conditions before actual machining, it will extend tool life and raise productivity. Optimization and choice of inserts with complex groove via internet may serve for manufacture enterprises all over the world. The milling inserts with three-dimensional complex grooves are optimized and chosen via Internet in this paper. The face-milling process is studied, with the mathematics models of cutting force for different shape of cutting edges established, the cutting forces predicted and stress-fields of different insert grooves analyzed by FEM, according to the predictable results and the most suitable insert groove for particular machining conditions are optimized and chosen. The complex groove optimization and choice are based on a client/server model, with the client and server being on different machines across the internet. Communication between the client and server uses the TCP/IP. The result of optimization and choice will be sent to the users via Internet. Manufacturers all over the world can get the desired insert groove without paying for expensive experiments. Thus, the cost and lead time of products are reduced. 展开更多
关键词 INTERNET-based face-milling insert groove optimization and choice
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Gradient-based optimization method for producing a contoured beam with single-fed reflector antenna
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作者 LIAN Peiyuan WANG Congsi +2 位作者 XIANG Binbin SHI Yu XUE Song 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第1期22-29,共8页
A gradient-based optimization method for producing a contoured beam by using a single-fed reflector antenna is presented. First, a quick and accurate pattern approximation formula based on physical optics(PO) is adopt... A gradient-based optimization method for producing a contoured beam by using a single-fed reflector antenna is presented. First, a quick and accurate pattern approximation formula based on physical optics(PO) is adopted to calculate the gradients of the directivity with respect to reflector's nodal displacements. Because the approximation formula is a linear function of nodal displacements, the gradient can be easily derived. Then, the method of the steepest descent is adopted, and an optimization iteration procedure is proposed. The iteration procedure includes two loops: an inner loop and an outer loop. In the inner loop, the gradient and pattern are calculated by matrix operation, which is very fast by using the pre-calculated data in the outer loop. In the outer loop, the ideal terms used in the inner loop to calculate the gradient and pattern are updated, and the real pattern is calculated by the PO method. Due to the high approximation accuracy, when the outer loop is performed once, the inner loop can be performed many times, which will save much time because the integration is replaced by matrix operation. In the end, a contoured beam covering the continental United States(CONUS) is designed, and simulation results show the effectiveness of the proposed algorithm. 展开更多
关键词 REFLECTOR ANTENNAS SINGLE FEED contoured BEAM gradient-based optimization method.
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Node deployment strategy optimization for wireless sensor network with mobile base station 被引量:7
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作者 龙军 桂卫华 《Journal of Central South University》 SCIE EI CAS 2012年第2期453-458,共6页
The optimization of network performance in a movement-assisted data gathering scheme was studied by analyzing the energy consumption of wireless sensor network with node uniform distribution. A theoretically analytica... The optimization of network performance in a movement-assisted data gathering scheme was studied by analyzing the energy consumption of wireless sensor network with node uniform distribution. A theoretically analytical method for avoiding energy hole was proposed. It is proved that if the densities of sensor nodes working at the same time are alternate between dormancy and work with non-uniform node distribution. The efficiency of network can increase by several times and the residual energy of network is nearly zero when the network lifetime ends. 展开更多
关键词 wireless sensor network mobile base station network optimization energy consumption balancing density ratio of sensor node network lifetime
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Optimal Tracking Control for a Class of Unknown Discrete-time Systems with Actuator Saturation via Data-based ADP Algorithm 被引量:4
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作者 SONG Rui-Zhuo XIAO Wen-Dong SUN Chang-Yin 《自动化学报》 EI CSCD 北大核心 2013年第9期1413-1420,共8页
为有致动器浸透和未知动力学的分离时间的系统的一个班的一个新奇最佳的追踪控制方法在这份报纸被建议。计划基于反复的适应动态编程(自动数据处理) 算法。以便实现控制计划,一个 data-based 标识符首先为未知系统动力学被构造。由介绍... 为有致动器浸透和未知动力学的分离时间的系统的一个班的一个新奇最佳的追踪控制方法在这份报纸被建议。计划基于反复的适应动态编程(自动数据处理) 算法。以便实现控制计划,一个 data-based 标识符首先为未知系统动力学被构造。由介绍 M 网络,稳定的控制的明确的公式被完成。以便消除致动器浸透的效果, nonquadratic 表演功能被介绍,然后一个反复的自动数据处理算法被建立与集中分析完成最佳的追踪控制解决方案。为实现最佳的控制方法,神经网络被用来建立 data-based 标识符,计算性能索引功能,近似最佳的控制政策并且分别地解决稳定的控制。模拟例子被提供验证介绍最佳的追踪的控制计划的有效性。 展开更多
关键词 最优跟踪控制 离散时间系统 饱和执行器 DP算法 控制方案 神经网络 性能指标 系统动力学
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连续双向拍卖中演化Risk-Based策略研究 被引量:1
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作者 赵旭 蔚承建 《计算机工程与应用》 CSCD 北大核心 2010年第3期236-240,共5页
Risk-Based策略是基于风险行为的代理策略。为了改善Risk-Based代理的行为,使交易价格迅速收敛于市场均衡价格,提高市场效率,提出利用粒子群优化算法演化Risk-Based策略参数。首先分析了影响Risk-Based代理行为的关键参数;之后提出了改... Risk-Based策略是基于风险行为的代理策略。为了改善Risk-Based代理的行为,使交易价格迅速收敛于市场均衡价格,提高市场效率,提出利用粒子群优化算法演化Risk-Based策略参数。首先分析了影响Risk-Based代理行为的关键参数;之后提出了改进的粒子群优化算法演化Risk-Based策略关键参数的模型。最后,在基于市场控制的模拟系统中采用连续双向拍卖机制对演化Risk-Based策略进行了实验评价,结果表明演化后的Risk-Based策略比演化前的策略更为优秀。 展开更多
关键词 Risk-based策略 粒子群优化 连续双向拍卖
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An improved multi-objective optimization algorithm for solving flexible job shop scheduling problem with variable batches 被引量:3
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作者 WU Xiuli PENG Junjian +2 位作者 XIE Zirun ZHAO Ning WU Shaomin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第2期272-285,共14页
In order to solve the flexible job shop scheduling problem with variable batches,we propose an improved multiobjective optimization algorithm,which combines the idea of inverse scheduling.First,a flexible job shop pro... In order to solve the flexible job shop scheduling problem with variable batches,we propose an improved multiobjective optimization algorithm,which combines the idea of inverse scheduling.First,a flexible job shop problem with the variable batches scheduling model is formulated.Second,we propose a batch optimization algorithm with inverse scheduling in which the batch size is adjusted by the dynamic feedback batch adjusting method.Moreover,in order to increase the diversity of the population,two methods are developed.One is the threshold to control the neighborhood updating,and the other is the dynamic clustering algorithm to update the population.Finally,a group of experiments are carried out.The results show that the improved multi-objective optimization algorithm can ensure the diversity of Pareto solutions effectively,and has effective performance in solving the flexible job shop scheduling problem with variable batches. 展开更多
关键词 flexible job shop variable batch inverse scheduling multi-objective evolutionary algorithm based on decomposition a batch optimization algorithm with inverse scheduling
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Multi-objective optimization for draft scheduling of hot strip mill 被引量:2
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作者 李维刚 刘相华 郭朝晖 《Journal of Central South University》 SCIE EI CAS 2012年第11期3069-3078,共10页
A multi-objective optimization model for draft scheduling of hot strip mill was presented, rolling power minimizing, rolling force ratio distribution and good strip shape as the objective functions. A multi-objective ... A multi-objective optimization model for draft scheduling of hot strip mill was presented, rolling power minimizing, rolling force ratio distribution and good strip shape as the objective functions. A multi-objective differential evolution algorithm based on decomposition (MODE/D). The two-objective and three-objective optimization experiments were performed respectively to demonstrate the optimal solutions of trade-off. The simulation results show that MODE/D can obtain a good Pareto-optimal front, which suggests a series of alternative solutions to draft scheduling. The extreme Pareto solutions are found feasible and the centres of the Pareto fronts give a good compromise. The conflict exists between each two ones of three objectives. The final optimal solution is selected from the Pareto-optimal front by the importance of objectives, and it can achieve a better performance in all objective dimensions than the empirical solutions. Finally, the practical application cases confirm the feasibility of the multi-objective approach, and the optimal solutions can gain a better rolling stability than the empirical solutions, and strip flatness decreases from (0± 63) IU to (0±45) IU in industrial production. 展开更多
关键词 hot strip mill draft scheduling multi-objective optimization multi-objective differential evolution algorithm based ondecomposition (MODE/D) Pareto-optimal front
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Simulation Optimization: A Review on Theory and Applications 被引量:4
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作者 WANG Long-Fei SHI Le-Yuan 《自动化学报》 EI CSCD 北大核心 2013年第11期1957-1968,共12页
模拟优化是在复杂真实系统的分析和优化的一个很强大的工具。在这份报纸,模拟优化的教程介绍和评论被给。模拟优化问题根据决定变量的内在的结构被分类(分离或连续) 。并且为模拟优化的一些重要技术详细被讨论包括他们的原则,实现过... 模拟优化是在复杂真实系统的分析和优化的一个很强大的工具。在这份报纸,模拟优化的教程介绍和评论被给。模拟优化问题根据决定变量的内在的结构被分类(分离或连续) 。并且为模拟优化的一些重要技术详细被讨论包括他们的原则,实现过程,优点和劣势,并且应用。未来研究方向也在这篇论文被提供。 展开更多
关键词 仿真优化 应用程序 综述 结构分类 优化问题
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An optimization method: hummingbirds optimization algorithm 被引量:1
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作者 ZHANG Zhuoran HUANG Changqiang +2 位作者 HUANG Hanqiao TANG Shangqin DONG Kangsheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第2期386-404,共19页
This paper introduces an optimization algorithm, the hummingbirds optimization algorithm(HOA), which is inspired by the foraging process of hummingbirds. The proposed algorithm includes two phases: a self-searching ph... This paper introduces an optimization algorithm, the hummingbirds optimization algorithm(HOA), which is inspired by the foraging process of hummingbirds. The proposed algorithm includes two phases: a self-searching phase and a guide-searching phase. With these two phases, the exploration and exploitation abilities of the algorithm can be balanced. Both the constrained and unconstrained benchmark functions are employed to test the performance of HOA. Ten classic benchmark functions are considered as unconstrained benchmark functions. Meanwhile, two engineering design optimization problems are employed as constrained benchmark functions. The results of these experiments demonstrate HOA is efficient and capable of global optimization. 展开更多
关键词 population-based algorithm global optimization hummingbirds optimization algorithm(HOA) engineering design optimization
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Clustering algorithm based on density function and nichePSO 被引量:4
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作者 Chonghui Guo Yunhui Zang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第3期445-452,共8页
This paper introduces niching particle swarm optimiza- tion (nichePSO) into clustering analysis and puts forward a cluster- ing algorithm which uses nichePSO to optimize density functions. Firstly, this paper improv... This paper introduces niching particle swarm optimiza- tion (nichePSO) into clustering analysis and puts forward a cluster- ing algorithm which uses nichePSO to optimize density functions. Firstly, this paper improves main swarm training models and in- creases their ability of space searching. Secondly, the radius of sub-swarms is defined adaptively according to the actual clus- tering problem, which can be useful for the niches' forming and searching. At last, a novel method that distributes samples to the corresponding cluster is proposed. Numerical results illustrate that this algorithm based on the density function and nichePSO could cluster unbalanced density datasets into the correct clusters auto- matically and accurately. 展开更多
关键词 niching particle swarm optimization (nichePSO) density-based clustering automatic clustering.
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Multi-agent decision support system for missile defense based on improved PSO algorithm 被引量:5
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作者 Zilong Cheng Li Fan Yulin Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第3期514-525,共12页
Ballistic missile defense system (BMDS) is important for its special role in ensuring national security and maintaining strategic balance. Research on modeling and simulation of the BMDS beforehand is essential as dev... Ballistic missile defense system (BMDS) is important for its special role in ensuring national security and maintaining strategic balance. Research on modeling and simulation of the BMDS beforehand is essential as developing a real one requires lots of manpower and resources. BMDS is a typical complex system for its nonlinear, adaptive and uncertainty characteristics. The agent-based modeling method is well suited for the complex system whose overall behaviors are determined by interactions among individual elements. A multi-agent decision support system (DSS), which includes missile agent, radar agent and command center agent, is established based on the studies of structure and function of BMDS. Considering the constraints brought by radar, intercept missile, offensive missile and commander, the objective function of DSS is established. In order to dynamically generate the optimal interception plan, the variable neighborhood negative selection particle swarm optimization (VNNSPSO) algorithm is proposed to support the decision making of DSS. The proposed algorithm is compared with the standard PSO, constriction factor PSO (CFPSO), inertia weight linear decrease PSO (LDPSO), variable neighborhood PSO (VNPSO) algorithm from the aspects of convergence rate, iteration number, average fitness value and standard deviation. The simulation results verify the efficiency of the proposed algorithm. The multi-agent DSS is developed through the Repast simulation platform and the constructed DSS can generate intercept plans automatically and support three-dimensional dynamic display of missile defense process. 展开更多
关键词 agent-based modeling missile defense system decision support system (DSS) variable neighborhood negative selection particle swarm optimization (PSO)
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OceanBase分布式关系数据库架构与技术 被引量:3
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作者 阳振坤 杨传辉 +3 位作者 韩富晟 王国平 杨志丰 成肖君 《计算机研究与发展》 EI CSCD 北大核心 2024年第3期540-554,共15页
关系数据库是当今社会的关键信息基础设施,互联网和数字化带来了高并发和海量数据,传统关系数据库均为集中式架构,处理能力和存储容量都捉襟见肘.OceanBase分布式关系数据库基于通用PC服务器,不仅实现了在线水平伸缩,还实现了机房故障... 关系数据库是当今社会的关键信息基础设施,互联网和数字化带来了高并发和海量数据,传统关系数据库均为集中式架构,处理能力和存储容量都捉襟见肘.OceanBase分布式关系数据库基于通用PC服务器,不仅实现了在线水平伸缩,还实现了机房故障自动无损容灾以及高倍率数据压缩等,已经应用于金融、政务、通信和互联网等行业.介绍了OceanBase分布式关系数据库的系统架构和关键技术,包括分布式事务处理、基于LSM-tree的存储系统以及分布式SQL优化器.详细阐述了OceanBase数据库的高可用和数据一致性,包括RPO为0和RTO小于8 s.也介绍了OceanBase数据库多租户机制,即采用了集群内原生多租户设计,在集群内实现多个互相独立的数据库服务.基于Sysbench和TPC-H评测基准,对比实验结果表明:1)在单机模式下,OceanBase的性能是MySQL的1.27倍至2倍多;2)在单主模式下,OceanBase的性能是MySQL的1.25倍至近2倍;3)在多主模式下,OceanBase的性能是MySQL的1.09倍至3.1倍,对于OLAP的复杂查询,OceanBase的性能是MySQL的6倍到327倍. 展开更多
关键词 关系数据库 分布式事务 基于LSM-tree存储 分布式SQL优化器 多租户
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计及构网型储能电站的新能源基地无功协调优化控制 被引量:7
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作者 林俐 马笑寒 丁文敏 《电力系统自动化》 北大核心 2025年第1期59-68,共10页
与传统火电主导的系统相比,缺乏同步电源支撑的新能源基地呈现低抗扰性和弱支撑性,采用构网型储能电站(GFMS)是一种有效的解决方案。文中首先对GFMS控制原理进行分析,确定了稳态及动态条件下GFMS的功率调节范围,并建立了GFMS运行模型。... 与传统火电主导的系统相比,缺乏同步电源支撑的新能源基地呈现低抗扰性和弱支撑性,采用构网型储能电站(GFMS)是一种有效的解决方案。文中首先对GFMS控制原理进行分析,确定了稳态及动态条件下GFMS的功率调节范围,并建立了GFMS运行模型。然后,提出了考虑GFMS辅助治理的无功协调优化控制策略,以适应无功协调优化及实时电压支撑需求。在无功协调优化阶段,以经济性最优和动态无功预留容量最大为目标,对无功源进行日前-日内集中优化;在实时电压支撑阶段,提出了一种基于并网点电压支撑需求的GFMS电压控制策略。选取中国西北地区某缺乏同步电源支撑的新能源基地为算例进行仿真,验证所提策略的有效性。结果表明,所提无功协调优化控制策略有效提高了新能源基地安全稳定水平,充分发挥了GFMS的作用。 展开更多
关键词 构网型储能电站 新能源基地 电压稳定 无功优化 电压支撑
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水驱油藏智能综合生产优化技术
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作者 李勇 张立侠 +5 位作者 陈一航 胡丹丹 马瑞程 王舒 李茜瑶 刘达望 《石油勘探与开发》 北大核心 2025年第3期677-691,共15页
针对目前闭环油藏管理中生产优化偏经验性、精度和效率较低、约束优化问题求解困难等问题,分析常用生产优化方法(模型)的原理和优缺点,提出一种兼顾效率和精度、综合考虑实时性与长期性、多种优化模型交互协同的水驱油藏智能综合生产优... 针对目前闭环油藏管理中生产优化偏经验性、精度和效率较低、约束优化问题求解困难等问题,分析常用生产优化方法(模型)的原理和优缺点,提出一种兼顾效率和精度、综合考虑实时性与长期性、多种优化模型交互协同的水驱油藏智能综合生产优化方法。该方法整合了油藏动态认识、简化物理模型和油藏数值模型等多种优化方法(模型),将不同模型的结果和认识相互耦合,以加速模型构建与拟合。采用现场实例对该方法进行解释和验证,结果表明,对于不同应用场景,存在不同的最佳生产优化模型,简化物理模型更适用于短期实时优化,基于模拟器的代理优化和流线模拟优化方法更适用于长期优化策略的制定,二者均需在油藏工程视角的合理约束下进行优化才具有实用价值。 展开更多
关键词 生产优化 油藏管理 简化物理模型 代理优化 流线模拟 数值模拟 动态分析
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求解U型拆卸线平衡问题的多目标教与学优化
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作者 李涛 李梓响 +2 位作者 郑晨昱 张子凯 张利平 《组合机床与自动化加工技术》 北大核心 2025年第2期229-235,共7页
考虑到在拆线问题中存在带有AND和OR优先关系的任务,结合最小化工作站数量、优化拆卸平衡、最小化危险程度和最小化需求度4个目标,建立了在U型布局下数学模型。由于U型的特殊布局,采用了基于操作排序的编码和解码来获得可行的操作方案... 考虑到在拆线问题中存在带有AND和OR优先关系的任务,结合最小化工作站数量、优化拆卸平衡、最小化危险程度和最小化需求度4个目标,建立了在U型布局下数学模型。由于U型的特殊布局,采用了基于操作排序的编码和解码来获得可行的操作方案。同时,对教与学优化算法两阶段进行部分更改,在教师阶段扩大了教学因子的取值范围,在学习阶段也加入了教师来指导学生学习,并加入Q学习来选择适合的教学因子,提出了基于Q学习的多目标教与学优化算法,并用Pareto非劣解和拥挤度距离机制来处理多目标问题的解。为了验证所提出的算法性能,将该算法与另外4种多目标算法进行对比,测试结果表明所提出的算法的性能优于所比较的算法。 展开更多
关键词 U型拆卸线 AND和OR优先关系 教与学优化算法 Q学习
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应用偏相干方法的车内路噪噪声源识别
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作者 刘志恩 胡宇航 +3 位作者 卢炽华 程灿 李晓龙 陈弯 《噪声与振动控制》 北大核心 2025年第4期203-209,共7页
为准确、高效地识别车辆在行驶时对于结构路噪贡献量较大的传递路径,引入偏相干分析方法。该方法无须测试路径的传递函数,只需给定工况下的响应结果即可,可大大提高测试效率。针对某款汽车在40 km/h工况低频路噪凸显的问题,分别采用部... 为准确、高效地识别车辆在行驶时对于结构路噪贡献量较大的传递路径,引入偏相干分析方法。该方法无须测试路径的传递函数,只需给定工况下的响应结果即可,可大大提高测试效率。针对某款汽车在40 km/h工况低频路噪凸显的问题,分别采用部件传递路径分析法和偏相干分析法进行结构路噪传递路径贡献量分析,以部件传递路径分析法分析结果为基准验证偏相干分析法的可靠性,最终两种方法得到的结果吻合良好。基于分析结果确定车内结构路噪传递的主要路径并进行改进,通过对左右后悬架衬套结构进行优化设计,使204 Hz频率点处噪声峰值显著降低,车内驾驶员右耳处的噪声总声压级降低3.09 dB(A)。 展开更多
关键词 声学 结构路噪 部件传递路径分析法 偏相干分析法 衬套优化
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电动汽车无线充电系统PBC-NDO复合控制器设计与参数优化
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作者 闫荣格 闫春娇 +1 位作者 杨庆新 张献 《电测与仪表》 北大核心 2025年第1期199-207,共9页
针对电动汽车无线充电系统在变电压间歇快速充电过程中由原副边线圈偏移和负载波动引起充电电压不稳定的问题,以及控制器参数大多依靠经验值和试凑法选取的问题,提出一种基于粒子群优化算法的无源控制器(passivity based controller,PBC... 针对电动汽车无线充电系统在变电压间歇快速充电过程中由原副边线圈偏移和负载波动引起充电电压不稳定的问题,以及控制器参数大多依靠经验值和试凑法选取的问题,提出一种基于粒子群优化算法的无源控制器(passivity based controller,PBC)与非线性干扰观测器(nonlinear disturbance observer,NDO)相结合的复合控制策略。针对无线电能传输(wireless power transfer,WPT)系统副边DC-DC变换器设计考虑干扰补偿的无源控制器,通过引入非线性干扰观测器对干扰量进行估计,将干扰估计值与无源控制器结合,设计适合电动汽车变电压间歇无线充电系统的PBC-NDO复合控制器,采用粒子群多目标优化算法对复合控制器进行参数寻优,进一步提高控制器的抗干扰性能以及动态响应性能,通过仿真和实验验证该策略的有效性。实验结果表明:复合控制器具有强抗干扰性和动态响应性,充电阶段最大稳态误差偏移率为2%,动态响应时间控制在0.6 ms内。 展开更多
关键词 变电压间歇充电 无线电能传输 无源控制器 非线性干扰观测器 参数优化
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考虑随机场载荷不确定性的连续体结构可靠性拓扑优化
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作者 程长征 王军基 +1 位作者 王选 杨博 《力学学报》 北大核心 2025年第2期535-544,共10页
提出了一种基于多项式混沌展开(polynomial chaos expansions,PCE)代理模型的高效可靠性拓扑优化(reliability-based topology optimization,RBTO)方法,用于处理考虑随机场载荷不确定性的可靠性设计问题.为此,建立了基于柔度响应定义的... 提出了一种基于多项式混沌展开(polynomial chaos expansions,PCE)代理模型的高效可靠性拓扑优化(reliability-based topology optimization,RBTO)方法,用于处理考虑随机场载荷不确定性的可靠性设计问题.为此,建立了基于柔度响应定义的概率约束下的结构体积分数最小化的单层循环RBTO模型,采用KarhunenLoève(K-L)展开式描述载荷随机场,利用蒙特卡罗模拟计算结构的失效概率.为了克服蒙特卡罗模拟方法在计算结构响应时计算成本高昂的问题,引入了PCE作为代理模型,高效地捕捉随机场载荷与结构柔度之间的复杂非线性关系.通过少量的高精度有限元分析样本,可以构建出高精度的PCE代理模型,一旦构建好代理模型的显式表达式,就可以直接基于代理模型在随机样本处计算失效概率,后续无需再进行有限元分析,从而在不牺牲太多精度的情况下,大幅减少后续计算的时间成本.详细推导了概率约束函数关于设计变量的灵敏度,采用移动渐近线方法(method of moving asymptotes,MMA)求解优化问题,将基于分析模型的RBTO方法与基于代理模型的RBTO方法作对比,验证了所提方法的有效性和优越性,并通过4个数值算例讨论了失效概率限值、柔度限值、载荷随机场均值与标准差以及相关长度对优化结果的影响.结果表明,不确定性因素增强时,结构需要消耗更多的材料来抵抗不确定性因素的干扰,另外基于代理模型的RBTO方法相对于基于分析模型的RBTO计算时间大幅缩短,提高了优化效率. 展开更多
关键词 拓扑优化 随机场 载荷不确定性 可靠性拓扑优化 多项式混沌展开
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基于性能的震损结构加固方案优选方法研究
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作者 吴小宾 高峰 +1 位作者 陈鹏 熊耀清 《地震工程与工程振动》 北大核心 2025年第3期202-211,共10页
基于地震预期损失和加固方案费用估计,提出了震损结构加固效费比指标。以震损结构加固效费比、结构预期修复时间作为定量指标,以施工技术、加固工期和功能影响作为定性指标,结合模糊数学理论的理想点优选算法和组合数有序加权算子,建立... 基于地震预期损失和加固方案费用估计,提出了震损结构加固效费比指标。以震损结构加固效费比、结构预期修复时间作为定量指标,以施工技术、加固工期和功能影响作为定性指标,结合模糊数学理论的理想点优选算法和组合数有序加权算子,建立了一套基于性能的震损结构加固方案优选方法。以某典型混凝土框架结构为研究对象,根据不同震损加固方案的增量动力分析结果,开展了震损结构纤维增强复合材料加固方案、减震加固方案以及隔震加固方案的对比优选研究。研究结果表明,提出的加固效费比指标,能客观、全面地反映不同加固方案对结构残余抗震能力提升产生的经济性影响;建立的基于性能的震损结构加固方案优选流程,能将客观条件和主观意愿相结合,科学高效地给出加固优选方案,为震损结构加固决策者提供参考依据。 展开更多
关键词 抗震加固 基于性能的地震工程 理想点算法 加固效费比 方案优选
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