面向对象的深度搜索遗传算法及其工程应用(II)——算法验证与工程应用

利用Matlab的非线性约束优化工具,通过数以千计的算例比较,对面向对象遗传算法的深度搜索策略的有效性进行了验证。研究结果表明,遗传算法的深度搜索策略是有效的,可最大限度地搜索到待优化问题的全局最优解。将滑坡支挡结构和深基坑支护结构的方案优化程序应用于多个实际工程以检验这些程序在结构优化和结构选型方面的性能。研究结果表明,单个的程序能较好地优化相应结构的设计方案,而多个程序的组合使用则可辅助工程人员选择合理的支挡结构型式。     

SATWE结构计算结果超限分析及其调整策略探讨

采用PKPM进行结构计算分析难免会存在计算结果超限问题,从工程实践表明,结构计算结果的超限问题可通过结构布置调整加以控制,本文结合实例根据SATWE计算结果提出结构布置优化调整策略,为同行提供参考。     

基于鱼群算法的耦合地震作用下钢结构-控制系统协同优化设计

鉴于目前土木工程的结构抗震优化设计方法尚未考虑到结构设计与控制设计之间的耦合相关性,极有可能丧失系统最优解,故运用协同优化策略对钢结构与控制系统进行一体化设计。首先建立耦合地震作用下含磁流变阻尼器(MRD)的运动方程,采用瞬时最优控制策略对其进行地震响应控制;进一步建立钢结构和MRD的优化模型,采用鱼群算法处理结构和MRD的多目标优化问题。优化结果表明:经协同优化设计后的受控结构性能优于串行设计的;耦合地震作用的优化结果稍大于只考虑水平地震作用的。     

我国民营企业资本结构优化研究

本文选择以中小型民营企业的资本结构问题为研究对象,通过分析企业的资本结构现状,从融资、经营和资产三方面提出具体的优化策略。     

大型结构优化设计系统3SOD

介绍了研究开发的大型结构优化设计系统3SOD的主要功能和特点。3SOD的优化分析系统采用作者提出的启发式分解算法,算法根据约束类型将原优化问题分解成两个子问题,借鉴满性能设计思想和利用结构单元的方向相对差商信息,引入自适应参数和相关求解策略,求解局域约束和全域约束下的两个优化子问题,从而获得原优化问题的优化解。3SOD具有良好的前后处理功能,对于大型结构的优化设计,该系统可获得良好的优化结果。     

面向对象的深度搜索遗传算法及其工程应用(Ⅱ)--算法验证与工程应用

利用Matlab的非线性约束优化工具，通过数以千计的算例比较，对面向对象遗传算法的深度搜索策略的有效性进行了验证。研究结果表明，遗传算法的深度搜索策略是有效的，可最大限度地搜索到待优化问题的全局最优解。将滑坡支挡结构和深基坑支护结构的方案优化程序应用于多个实际工程以检验这些程序在结构优化和结构选型方面的性能。研究结果表明，单个的程序能较好地优化相应结构的设计方案，而多个程序的组合使用则可辅助工程人员选择合理的支挡结构型式。     

关注活动经验 完善认知结构

文章剖析了优化数学活动的经验策略,深化理解数学知识,有效地运用数学经验去解决数学问题,完善学生的认知结构。     

面向建筑设计的结构优化策略

澄清结构优化在制造业与建筑业中的区别,使结构优化不仅能作为建筑设计的后合理化工具,更能成为服务于建筑方案推敲的设计策略,基于案例从结构影响空间的内核、表皮、断面3方面,为建筑师梳理了适应多样化设计需求的结构优化策略。     

高层建筑结构抗震设计问题及优化策略

结合上海环球金融中心的结构设计,介绍了高层建筑抗震设计中存在的问题,从结构体系、结构均匀性、结构延性三方面,探讨了高层建筑结构抗震设计的优化策略,以此增强高层建筑结构的抗震性能。     

高层建筑结构设计的问题及对策探讨

根据高层建筑结构设计的原则,分析了高层建筑结构设计中存在的问题,从结构方案选择、抗震设计、结构性能等角度,提出了高层建筑结构设计优化策略,使高层建筑结构满足安全性、合理性及适用性要求。     

钢管混凝土桁架组合梁式桥优化设计研究

针对钢管混凝土桁架组合梁式桥中杆件截面离散的问题,提出两级优化法与满应力法相结合的优化方法,通过一工程实例优化设计,测试了该优化方法的效率,取得了显著经济效益.     

Lifetime-oriented multi-objective optimization of structural maintenance considering system reliability, redundancy and life-cycle cost using GA

The need to design and construct structural systems with adequate levels of reliability and redundancy is widely acknowledged. It is as crucial that these desired levels are maintained above target levels throughout the life of the structure. Optimization has served well in providing safer and more economical maintenance strategies. Lifetime maintenance optimization based on system reliability has already been proposed. It is still needed, however, to incorporate redundancy in the lifetime maintenance optimization process. Treating both system reliability and redundancy as criteria in the lifetime optimization process can be highly rewarding. The complexity of the process, however, requires the automation of solving the optimization problem. Genetic algorithms (GAs) are used in this study to obtain solutions to the multi-objective optimization problems considering system reliability, redundancy and life-cycle cost (LCC). An approach to provide the optimization program the ability to optimally select what maintenance actions are applied, when they are applied, and to which structural components they are applied is presented. Two different strategies are proposed. The first strategy has the ability to optimally select mixed maintenance types to apply to different parts of the structure at the same time. This strategy can be used in cases where any combination of different maintenance options can be practically applied to any part of the structure. The application of this strategy on truss structures is shown in a numerical example. The second strategy can be used when a limited number of possibilities of practical maintenance options are available. The application of this strategy to bridge structures is shown in a numerical example. The greatest advantage of the proposed approach (both strategies) is its ability to avoid the application of maintenance interventions to structural components that are not critical.     

计算机辅助优化技术在建筑结构设计中的运用

介绍一个基于计算机的结构优化实用算法以及基于此算法的实用软件系统,该软件系统可以用来指导或优化钢筋混凝土房屋结构的设计工作,节约土建成本,提高设计质量以及实现设计自动化。目前该系统已用于三十多项大型房屋结构设计优化项目,取得了巨大的经济效益。     

基于BIM技术的冀中南传统民居物理环境模拟与优化探析

传统民居的再生利用在传承传统村落肌理、生态技术的同时,营造舒适的居住环境才是其持续再生的主动力。基于BIM技术的模拟及可视化特点,针对传统民居再生利用中的物理环境进行了优化策略的探讨及光环境、热环境、风环境进行了数值模拟优化分析,为传统民居居住环境的评估和优化提供了有益的参考。     

气候适应型绿色公共建筑环境性能优化设计策略研究

随着经济全球化的发展,生态环境的破坏,导致日益严峻的环境问题越来越受到人们的关注。本文基于不同气候下,对绿色公共建筑环境性能优化设计进行了研究。并结合实际情况,分析出了气候适应型绿色公共建筑环境性能的优化对策。     

Optimal operation of a hospital power plant

In this paper the operation of an Academic Hospital installation is evaluated by simulation and optimization on a yearly base. A mathematical model has been developed, which is based on energy balances of the installed components. Manufacturer specifications of the components are used for calculating the parameters. The model is formulated using vector equations. Advantages of this type of model formulations are presented. The tools used for optimization are custom developed back-tracking methods for calculating a good starting point and a SQP optimization tool for finding the optimum. Detailed control strategies are calculated for three types of optimization strategies simulated. The simulation results show the impact of the choice of a control strategy on the optimized operation. The results are also applicable for on-line setpoint optimization.     

Substructuring for Structural Optimization in a Parallel Processing Environment

Design optimization of large structures can be attempted through a substructure strategy. In this strategy, the structure is divided into smaller substructures that are clustered to obtain a sequence of subproblems. Solution to the large problem is obtained iteratively through repeated solutions to the modest subproblems. Substructure strategies, in sequential and parallel computational environments on a Cray-YMP computer, have been implemented in a design test bed CometBoards. The issues encountered during substructure solution and their resolution are discussed under (1) coupling and constraint formulation, (2) differences in optimal solutions, and (3) amount of computation. Coupling between subproblems and separating constraints into local and global sets promote convergence of the iterative process. The substructure strategy can converge to different local optimal designs with equal minimum weight. Substructure optimization can be computation-intensive. However, in a parallel computational mode, it can effectively use assigned processors.     

基于GASA混合优化策略的双层规划模型求解算法研究

本文提出用遗传—模拟退火算法(GASA)混合优化策略来求解双层规划模型。混合优化策略结合了遗传算法的并行结构和模拟退火算法的概率突跳性,提高了找到全局最优解的可靠性和计算效率。数值模拟实验表明算法性能良好,GASA混合优化策略求得全局最优解时的进化代数比单一的遗传算法减少约35％,比模拟退火算法的迭代次数减少约50％。     

Study on the Shape Optimization of Cable-Stiffened Single-Layer Latticed Shells

The cable-stiffened single-layer latticed shell is a new type of spatial structure. In this paper, a shape optimization method is proposed for two kinds of cable-stiffened single-layer latticed shells. Firstly, an optimization algorithm is proposed to minimize the strain energy of shell. Interior-point method, conjugate gradient method and golden section method are adopted as the approach of constraint optimization, the minimization algorithm and the line search strategy, respectively. Secondly, the derivatives of stiffness matrixes of two kinds of cable-stiffened systems are discussed. Finally, optimization program is programmed in MATLAB and a numerical example is carried out. The linear buckling load, the displacement and the stress distribution of the optimized shells are investigated. According to numerical results, the structural behaviours of cable-stiffened single-layer latticed shells are improved significantly. The optimization method suggested in this paper is valid.