基于遗传算法的冷水机组负荷分配与出水温度的优化

根据冷水机组的能耗与其部分负荷率的相关特性,提出基于遗传算法的冷水机组最小能耗的优化分配,从而获得各台机组的负荷分配率以及在此分配下的冷机出水温度优化设定,并对该分配进行MATLAB仿真.结果表明,该策略能够优化机组的运行并降低系统能耗.     

A multilevel genetic algorithm for the optimum design of structural control systems

A multilevel genetic algorithm (MLGA) is proposed in this paper for solving the kind of optimization problems which are multilevel structures in nature and have features of mixed‐discrete design variables, multi‐modal and non‐continuous objective functions, etc. Firstly, the formulation of the mixed‐discrete multilevel optimization problems is presented. Secondly, the architecture and implementation of MLGA are described. Thirdly, the algorithm is applied to two multilevel optimization problems. The first one is a three‐level optimization problem in which the optimization of the number of actuators, the positions of actuators and the control parameters are considered in different levels. An actively controlled tall building subjected to strong wind action is considered to investigate the effectiveness of the proposed algorithm. The second application considers a combinatorial optimization problem in which the number and configuration of actuators are optimized simultaneously, an actively controlled building under earthquake excitations is adopted for this case study. Finally, some results and discussions about the application of the proposed algorithm are presented. Copyright © 2002 John Wiley & Sons, Ltd.     

Camera calibration using a genetic algorithm

An autonomous robot will have to detect moving obstacles online before it can plan its collision-free path, while navigating in a dynamic environment. The robot collects information about the environment with the help of a camera and determines the inputs for its motion planner through image analysis. The present article deals with issues related to camera calibration and online image processing. The problem of camera calibration is treated as an optimization problem and solved using a genetic algorithm so as to achieve minimum distorted image plane error. The calibrated vision system is then utilized for the detection and identification of the objects by analysing the images collected at regular intervals. For image processing, five different operations, such as median filtering, thresholding, perimeter estimation, labelling and size filtering, have been carried out. To show the effectiveness of the developed camera-based vision system, inputs of the motion planner of a navigating robot are calculated for two different cases. It is observed that online detection of the shapes and configurations of the obstacles is possible by using the vision system developed.     

基于遗传算法的涡街信号随机共振检测方法

涡街流量计在工业现场工作时,输出信号易叠加噪声,尤其在小流量测量时,涡街信号易被现场噪声淹没,导致测量受限.针对涡街信号处理,提出一种基于遗传算法的双调制随机共振方法.该方法对输入信号进行频率和幅值双调制后进入非线性双稳系统,以系统输出信号的信噪比为适应度函数,通过二进制编码,将调制频率和幅值组合成一个二进制字符串,同...     

基于改进量子遗传算法的有源噪声控制方法

提出了一种基于改进量子遗传算法的格型IIR滤波器结构的有源噪声控制方法——改进的量子遗传算法（IQGA）。其核心是在对量子门更新过程进行改进的基础上，引入群体灾变和自适应搜索网格的策略。IQGA不仅收敛速度快，还可以改变基本遗传算法（GA）的局部搜索能力，克服基本遗传算法存在的未成熟收敛问题。仿真结果表明，该算法可以有效地实现噪声控制。     

Developing a method to generate semi-distributed layouts by genetic algorithm

Recent research in industries shows that existing layout configurations do not satisfy the needs of multi-product enterprises in turbulent environments but within new layout strategies, distributed layouts have deserved more attention in most manufacturing environments and have a promising potential to cope with demand disturbances. This study is an attempt to design weighted distributed layouts via considering machine independent capabilities by a resource elements (REs) approach, which has caused generation of a new type of distributed layout named semi-distributed layout. REs are used to define processing requirements of parts and processing capabilities of machines. Another contribution of this paper is applying genetic algorithms (GAs) to distribute REs to find the optimal assignment of machines to available locations in such a way the travelled distances of parts are minimised and the accessibility of them to the required machines are maximised. The methodology of this paper is illustrated using a two-phase procedure. First, all machining facilities are divided into a set of REs based on their capabilities and second, the weighted connections among REs are considered to distribute them over the floor through implementing the developed GA. To evaluate the methodology, the proposed algorithm is tested with three illustrative examples obtained from the literature, in which two of them are comparable with outputs of simulated annealing (SA). The comparison between the outputs of the GA and the SA on the same cases presents that for large size problems, the GA significantly outperforms the SA.     

Systematic fatigue spectrum editing by fast wavelet transform and genetic algorithm

Fatigue testing is critical in order to establish the service life of load-bearing components and structures. The extensive time associated with full fatigue spectrum testing can lead to prohibitive costs. A significant need exists for a fatigue load spectrum editing methodology, based on the mechanics of fatigue, that produces load spectra that can replicate service damage in laboratory testing and can lead to compressed testing times and reduced costs. In this work, a wavelet genetic (WAVEGEN) algorithm is developed to edit fatigue loading spectra using wavelet analysis to greatly reduce the length of a spectrum while retaining the same damage accumulation characteristics. In addition, an optimization protocol using a genetic algorithm is included within this process to automatically select the best wavelet editing parameters. The algorithm is designed to identify the most suitable wavelet type, filter, and level to optimally edit a given fatigue spectrum and ensure equivalence between edited and unedited spectra from a damage perspective. The algorithm was applied to two well-known aircraft fatigue spectra: Fighter Aircraft Loading Standard for Fatigue evaluation (FALSTAFF) and Transport Wing Standard (TWIST). The proposed approach has demonstrated that both spectra can be compressed significantly even while ensuring equivalence from a damage perspective.     

A structural damage identification method based on genetic algorithm and vibrational data

The problem of damage identification in framed structures using vibrational data is considered. The identification problem is modelled as an optimization task and the use of measured natural frequencies as well as modeshape information in the construction of objective functions is discussed. In a first attempt, a standard genetic algorithm is shown to be ineffective in obtaining the correct damage distribution in test problems. Using domain knowledge, modifications are introduced in the coding process, in the initial population generation, in the fitness function, and in the genetic operators, leading to a promising tool to solve this class of problems. Synthetic problems, with the addition of noise in the simulated measured data associated with the damaged structure, are analysed in order to assess the capability of the proposed technique. Copyright © 2006 John Wiley & Sons, Ltd.     

基于迷宫算法和遗传算法的船舶管路路径规划

船舶管路的多样性和布局环境中约束的复杂性导致管路设计效率低下.为辅助设计人员提高管路设计效率并减少人为错误,提出了一种新的管路设计方法.首先,基于轴平行包围盒简化管路布局空间,利用栅格法对其进行离散化,并赋予空间网格特定的能量值,构建管路布局优化问题的数学模型.其次,基于遗传算法的框架,引入改进迷宫算法,提出管路路径规划方法,其中:迷宫搜索中引入辅助点的概念,增加了遗传算法中初始种群的多样性,有利于提高遗传算法的全局搜索能力;提出了定长度的编码方法,简化了管路染色体处理难度,提高了算法性能;基于引入方向优先搜索策略的迷宫算法,设计定长度编码遗传算子,保证了子代个体的质量,提高算法的收敛速度.最后,基于仿真试验,验证算法的性能.试验结果表明了该方法的可行性和高效率,以及其对实际管路布局工作具有指导意义.     

基于遗传算法的家用保安机器人路径规划方法

将领域知识与遗传算法相结合,提出了一种针对家用保安机器人的路径规划方法.该算法采用改进的栅格化方法来描述家庭环境,重新定义了路径适应度函数的评价方法,并设计有效的路径遗传算子.仿真结果表明了该算法的正确性和有效性.利用该算法实现了在实际家庭环境下保安机器人的路径规划与动态避障.     

退火-遗传算法寻优及其实现

分析了遗传算法及退火算法的优缺点,提出用退火算法改进遗传算法局部的最优值搜索效率低问题。退火算法与遗传算法融合后,使算法在寻优结果上更加迅速精确。通过水泥的配比工程实例,与单纯的遗传算法的结果进行对比,说明该方法是有效的。     

用于彩色图像分割的改进遗传FCM算法

本文提出了一种适用于彩色图像分割的遗传模糊C均值聚类(GAFCM)算法.该算法使用Ohta等人提出的彩色特征集中的第一个分量作为图像像素的一维特征向量,并利用由像素空间到特征空间的映射来改进目标函数,从而大大降低了运算量;使用对特征空间结构没有特殊要求的特征距离代替欧氏距离,从而克服了特征空间结构对聚类结果的影响;使用引入FCM优化的遗传算法来搜索最优解,从而提高了搜索速度.实验表明,该算法不但能很好地分割彩色图像,而且具有运算量小、收敛速度快的优点.     

本体概念分类的遗传算法

提出了一种基于遗传算法的本体概念分类规则学习方法(GAOCL).该方法从已有的本体库或知识库中获取实例作为训练样本,通过遗传算法获取相关的概念分类规则,实现概念实例的有效分类,以达到扩充和丰富本体的目的.首先,在编码过程中采用了可变长度的规则集合作为个体,以满足不同概念对分类规则数目的不同要求.其次,定义了规则集相对覆盖率,并以此作为适应值函数,评估个体对概念实例的分类效果,实现优化迭代.最后,给出了基于遗传算法的本体分类规则学习算法.利用一组标准样本集对该算法与同类算法进行了比较,实验结果表明该算法具有很好的收敛性,并且能获得较好的分类效果.     

Minimising material handling cost in cell formation with alternative processing routes by grouping genetic algorithm

The alternative processing route is one of the important design factors for the cell formation problem (CFP) in cellular manufacturing systems (CMSs). Genetic algorithm (GA) is a popular method for solving the CFPs, because GA is capable of searching large regions of the solution's space while being less susceptible to getting trapped in local optima. However, the disadvantage of classical GAs is that the number of manufacturing cells should be known in advance. Knowing the actual number of manufacturing cells is relatively difficult before the CMS design is determined. Grouping genetic algorithm (GGA) is capable of solving CFP without predetermination of the number of cells, which is introduced by Falkenauer's GGA (1998 Falkenauer, E. 1998. Genetic Algorithms for Grouping Problem, New York: Wiley.  [Google Scholar]). In order to adopt the GGA on CFP with alternative processing routes, we develop a new chromosome representation, a local optimisation algorithm for crossover operator and special mutation operators. These efforts ensure the efficiency of our method and are indicated in the numerical examples, and improved solutions are also obtained in the numerical examples.     

基于免疫遗传算法优化的模糊神经元网络控制器在全阶精馏塔模型中的控制仿真研究

本文提出了一种免疫遗传算法优化的模糊控制器,利用免疫遗传算法的全局搜索功能和神经元的自学习能力,提高了模糊控制器的控制精度和抗干扰能力。将该控制器用于全阶精馏塔模型仿真,仿真结果表明该控制器可以有效地消除静态误差,并在控制过渡过程中也有很好的鲁棒性,实际应用效果也表明了该方法的优越性。     

新型多目标遗传算法及其在导弹射击效能优化中的应用

多目标规划是一类重要的优化模型，有着广泛的实际应用，但其求解至今仍是运筹学的一个难点．针对一般约束多目标优化问题，在设计了新的适应度函数和选择算子的基础上，提出一种新型多目标遗传算法．将其应用于导弹对集群目标射击效能优化问题，验证了算法的有效性．     

遗传算法与惩罚函数法在机械优化设计中的应用

提出了应用于机械优化设计的"遗传算法+惩罚函数法"的通用算法.它非常适合求解复杂的非线性约束优化问题.本通用算法既克服了传统优化方法的缺点,得到了一个较为理想的全域最优解;同时也改善了遗传算法的局限性.     

遗传算法的改进策略及其在桥梁抗震优化设计中的应用效果

本文论述了采用遗传算法进行结构优化设计时遇到的诸如计算量大、早熟收敛和边界探索不足等棘手问题，提出了三个解决对策，编制了计算程序，其在桥梁抗震代化设计中的应用效果表明，改进后的遗传算法不但提高了计算速度，而且在尽可能短的时间内找到最好的优化解。     

基于遗传算法的多孔介质热物性参数的辨识方法

提出了一种基于遗传算法(Genetic Algorithm,GA)的多孔介质相关热物性参数辨识方法.该方法改进初始条件、适应度值以及终止条件的选取,并利用种群的均方差检测种群的单一性,在保留历史最佳个体的基础上,保持种群的多样性,从而跳过局部最优点,达到参数辨识的目的.测量结果表明,采用该方法对模拟数据反演参数的相对误差最大为0.159%,对样品的实测温度与理论计算温度的平均误差为0.046℃.说明该方法对多孔介质相关热物性参数有着较强的辨识能力,是一种具有一定的精度和可靠性的参数辨识方法.     

Satellite image segmentation using hybrid variable genetic algorithm

Image segmentation is an important task in image processing and analysis. Many segmentation methods have been used to segment satellite images. The success of each method depends on the characteristics of the acquired image such as resolution limitations and on the percentage of imperfections in the process of image acquisition due to noise. Many of these methods require a priori knowledge which is difficult to obtain. Some of them are parametric statistical methods that use many parameters which are dependent on image property. In this article, a new unsupervised nonparametric method is developed to segment satellite images into homogeneous regions without any a priori knowledge. The new method is called hybrid variable genetic algorithm (HVGA). The variability is found in the variable number of cluster centers and in the changeable mutation rate. In addition, this new method uses different heuristic processes to increase the efficiency of genetic algorithm in avoiding local optimal solutions. Experiments performed on two different satellite images (Landsat and Spot) proved the high accuracy and efficiency of HVGA compared with another two unsupervised and nonparametric segmentation methods genetic algorithm (GA) and self‐organizing map (SOM). The verification of the results included stability and accuracy measurements using an evaluation method implemented from the functional model (FM) and field surveys. © 2009 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 19, 199–207, 2009