Hybridization strategies for continuous ant colony optimization and particle swarm optimization applied to data clustering

Ant colony optimization (ACO) and particle swarm optimization (PSO) are two popular algorithms in swarm intelligence. Recently, a continuous ACO named ACOR was developed to solve the continuous optimization problems. This study incorporated ACOR with PSO to improve the search ability, investigating four types of hybridization as follows: (1) sequence approach, (2) parallel approach, (3) sequence approach with an enlarged pheromone-particle table, and (4) global best exchange. These hybrid systems were applied to data clustering. The experimental results utilizing public UCI datasets show that the performances of the proposed hybrid systems are superior compared to those of the K-mean, standalone PSO, and standalone ACOR. Among the four strategies of hybridization, the sequence approach with the enlarged pheromone table is superior to the other approaches because the enlarged pheromone table diversifies the generation of new solutions of ACOR and PSO, which prevents traps into the local optimum.     

基于蚁群聚类算法的非线性系统辨识

基于T-S模型提出一种非线性系统的模型辨识方法.利用蚁群聚类算法进行结构辨识,确定系统的模糊空间和模糊规则数.在聚类的基础上,利用遗传算法辨识模糊模型的后件加权参数,得到一个精确的模糊模型,从而实现了参数辨识.仿真结果验证了所提出方法的有效性,表明该方法能够实现非线性系统的辨识,而且辨识精度较高.     

基于信息素的自适应连续域混合蚁群算法

针对连续域混合蚁群算法（HACO）易陷入局部最优和收敛速度较慢的问题,提出了基于信息素的自适应连续域混合蚁群算法（QAHACO）。首先提出了一种新的解更新方式,对档案中的解进行信息素挥发,扩大了搜索范围,提高了算法的全局搜索能力,并且自适应地调整信息素挥发速率,更好地平衡收敛速度和收敛精度,其次采用了一种信息分享机制,将当前解与其他所有解的平均距离和当前解与至今最优解的距离相结合,进一步加快收敛速度。通过对测试函数进行仿真实验,结果表明,和连续域蚁群及其改进算法相比,QAHACO算法的寻优能力明显提高,寻优速度有一定的优势。     

基于聚类分析的增强型蚁群算法

针对蚁群算法存在的早熟收敛、搜索时间长等不足,提出一种增强型蚁群算法.该算法构建了一优解池,保存到当前迭代为止获得的若干优解,并提出一种基于邻域的聚类算法,通过对优解池中的元素聚类,捕获不同的优解分布区域.该算法交替使用不同簇中的优解更新信息素,兼顾考虑了搜索的强化性和分散性.针对典型的旅行商问题进行仿真实验,结果表明该算法获得的解质量高于已有的蚁群算法.     

基于人工蜂群的连续域蚁群优化算法

连续域蚁群优化算法是蚁群优化算法的一个重要研究方向,针对连续域蚁群优化算法(ACOR)计算时间较长、易陷入局部最优的问题,提出了一种基于人工蜂群的连续域蚁群优化算法(ABCACOR)。首先,引入一种替代机制来选择指导解,以替换原来的基于排序的选择方式,目的是节约计算时间和尽可能地保持搜索的多样性;其次,结合人工蜂群算法的搜索策略来提高算法的全局搜索能力,进一步减少计算时间和提高求解精度。通过对大量的测试函数进行仿真实验,结果表明,ABC-ACOR算法较现有的一些连续域蚁群算法具有更好的寻优能力。     

蚁群模糊聚类的图像分割

蚁群算法的离散性、并行性、鲁棒性、正反馈性特点,非常适合于图像分割.但基本蚁群算法中蚂蚁运动的随机性使得算法进化速度慢且易于陷入局部最小等缺陷.提出了一种基于改进的蚁群模糊聚类的图像分割方法,给出了多种信息素的更新方式.针对算法循环次数多,计算量大的问题,综合考虑图像中像素的灰度,邻域平均灰度,梯度等特征来设置初始聚类中心进行蚁群模糊聚类.实验结果表明,该方法在图像分割中的确能够得到较好的分割结果.     

A size-insensitive integrity-based fuzzy c-means method for data clustering

Fuzzy c-means (FCM) is one of the most popular techniques for data clustering. Since FCM tends to balance the number of data points in each cluster, centers of smaller clusters are forced to drift to larger adjacent clusters. For datasets with unbalanced clusters, the partition results of FCM are usually unsatisfactory. Cluster size insensitive FCM (csiFCM) dealt with “cluster-size sensitivity” problem by dynamically adjusting the condition value for the membership of each data point based on cluster size after the defuzzification step in each iterative cycle. However, the performance of csiFCM is sensitive to both the initial positions of cluster centers and the “distance” between adjacent clusters. In this paper, we present a cluster size insensitive integrity-based FCM method called siibFCM to improve the deficiency of csiFCM. The siibFCM method can determine the membership contribution of every data point to each individual cluster by considering cluster's integrity, which is a combination of compactness and purity. “Compactness” represents the distribution of data points within a cluster while “purity” represents how far a cluster is away from its adjacent cluster. We tested our siibFCM method and compared with the traditional FCM and csiFCM methods extensively by using artificially generated datasets with different shapes and data distributions, synthetic images, real images, and Escherichia coli dataset. Experimental results showed that the performance of siibFCM is superior to both traditional FCM and csiFCM in terms of the tolerance for “distance” between adjacent clusters and the flexibility of selecting initial cluster centers when dealing with datasets with unbalanced clusters.     

ECG heart beat classification method based on modified ABC algorithm

Electrocardiogram is the most commonly used tool for the diagnosis of cardiologic diseases. In order to help cardiologists to diagnose the arrhythmias automatically, new methods for automated, computer aided ECG analysis are being developed. In this paper, a Modified Artificial Bee Colony (MABC) algorithm for ECG heart beat classification is introduced. It is applied to ECG data set which is obtained from MITBIH database and the result of MABC is compared with seventeen other classifier's accuracy.In classification problem, some features have higher distinctiveness than others. In this study, in order to find higher distinctive features, a detailed analysis has been done on time domain features. By using the right features in MABC algorithm, high classification success rate (99.30%) is obtained. Other methods generally have high classification accuracy on examined data set, but they have relatively low or even poor sensitivities for some beat types. Different data sets, unbalanced sample numbers in different classes have effect on classification result. When a balanced data set is used, MABC provided the best result as 97.96% among all classifiers.Not only part of the records from examined MITBIH database, but also all data from selected records are used to be able to use developed algorithm on a real time system in the future by using additional software modules and making adaptation on a specific hardware.     

FAMACROW: Fuzzy and ant colony optimization based combined mac,routing, and unequal clustering cross-layer protocol for wireless sensor networks

This paper presents Fuzzy and Ant Colony Optimization Based Combined MAC, Routing, and Unequal Clustering Cross-Layer Protocol for Wireless Sensor Networks (FAMACROW) consisting of several nodes that send sensed data to a Master Station. FAMACROW incorporates cluster head selection, clustering, and inter-cluster routing protocols. FAMACROW uses fuzzy logic with residual energy, number of neighboring nodes, and quality of communication link as input variables for cluster head selection. To avoid hot spots problem, FAMACROW uses an unequal clustering mechanism with clusters closer to MS having smaller sizes than those far from it. FAMACROW uses Ant Colony Optimization based technique for reliable and energy-efficient inter-cluster multi-hop routing from cluster heads to MS. The inter-cluster routing protocol decides relay node considering its: (i) distance from current cluster head and that from MS (for energy-efficient inter-cluster communication), (ii) residual energy (for energy distribution across the network), (iii) queue length (for congestion control), (iv) delivery likelihood (for reliable communication). A comparative analysis of FAMACROW with Unequal Cluster Based Routing [33], Unequal Layered Clustering Approach [43], Energy Aware Unequal Clustering using Fuzzy logic [37] and Improved Fuzzy Unequal Clustering [35] shows that FAMACROW is 41% more energy-efficient, has 75–88% more network lifetime and sends 82% more packets compared to Improved Fuzzy Unequal Clustering protocol.     

Size optimization for hybrid photovoltaic–wind energy system using ant colony optimization for continuous domains based integer programming

In this paper, ant colony optimization for continuous domains (ACO_R) based integer programming is employed for size optimization in a hybrid photovoltaic (PV)–wind energy system. ACO_R is a direct extension of ant colony optimization (ACO). Also, it is the significant ant-based algorithm for continuous optimization. In this setting, the variables are first considered as real then rounded in each step of iteration. The number of solar panels, wind turbines and batteries are selected as decision variables of integer programming problem. The objective function of the PV–wind system design is the total design cost which is the sum of total capital cost and total maintenance cost that should be minimized. The optimization is separately performed for three renewable energy systems including hybrid systems, solar stand alone and wind stand alone. A complete data set, a regular optimization formulation and ACO_R based integer programming are the main features of this paper. The optimization results showed that this method gives the best results just in few seconds. Also, the results are compared with other artificial intelligent (AI) approaches and a conventional optimization method. Moreover, the results are very promising and prove that the authors’ proposed approach outperforms them in terms of reaching an optimal solution and speed.     

基于模糊核c-means 算法的位置指纹聚类

提出一种针对位置指纹的模糊核c-means聚类算法.将位置指纹归结为一种服从正态分布的区间值数据以反映接入点信号强度采样值的不确定性,通过区间中值和大小确定的正态分布函数将位置指纹映射为特征空间中的一点,并在该特征空间中采用基于核方法的模糊c-means算法对其进行聚类.通过ZigBee定位实验表明,该方法对于位置指纹的分类效果明显好于基于信号强度平均值的c-means聚类,可在保证定位精度的前提下有效降低定位的计算量.     

蚁群优化与模糊聚类结合的文本聚类研究

针对模糊文本聚类算法（FCM）对输入顺序以及初始点敏感的问题,提出了一种使用蚁群优化的模糊聚类算法（FACA）。该算法采用蚁群聚类算法（ACA）找到聚类的初始中心点,以解决模糊聚类的输入顺序以及初始点敏感等问题。模糊文本聚类算法的线性复杂度使其更便于在计算机实现。与经典的基本模糊聚类以及蚁群聚类在真实数据集上仿真相比较,结果表明经蚁群优化过的模糊聚类算法（FACA）效果更有效,更适合应用于大型的数据集。     

基于蚁群聚类的历史灾害分级方法

针对历史灾害记录的描述性、简约性问题,提出一种基于蚁群聚类的历史灾害分级方法。利用灰色关联分析方法对灾害数据进行归一化处理后,再通过蚁群自动聚类的结果来划分历史灾害的等级,以避免人为的主观任意性干扰。通过与其他分级方法的性能对比,实验结果证明该方法具有较高的精确性和实用性。     

A hybrid ant colony optimization algorithm for optimal multiuser detection in DS-UWB system

A hybrid ant colony optimization algorithm is proposed by introducing extremal optimization local-search algorithm to the ant colony optimization (ACO) algorithm, and is applied to multiuser detection in direct sequence ultra wideband (DS-UWB) communication system in this paper. ACO algorithms have already successfully been applied to combinatorial optimization; however, as the pheromone accumulates, we may not get a global optimum because it can get stuck in a local minimum resulting in a bad steady state. Extremal optimization (EO) is a recently developed local-search heuristic method and has been successfully applied to a wide variety of optimization problems. Hence in this paper, a hybrid ACO algorithm, named ACO-EO algorithm, is proposed by introducing EO to ACO to improve the local-search ability of the algorithm. The ACO-EO algorithm is applied to multiuser detection in DS-UWB communication system, and via computer simulations it is shown that the proposed hybrid ACO algorithm has much better performance than other ACO algorithms and even equal to the optimal multiuser detector.     

基于模糊蚁群的加权蛋白质复合物识别算法

针对蚁群融合模糊C-means （FCM）聚类算法在蛋白质相互作用网络中进行复合物识别的准确率不高、召回率较低以及时间性能不佳等问题进行了研究,提出一种基于模糊蚁群的加权蛋白质复合物识别算法FAC-PC（algorithm for identifying weighted protein complexes based on fuzzy ant colony clustering）。首先,融合边聚集系数与基因共表达的皮尔森相关系数构建加权网络;其次提出EPS（essential protein selection）度量公式来选取关键蛋白质,遍历关键蛋白质的邻居节点,设计蛋白质适应度PFC（protein fitness calculation）来获取关键组蛋白质,利用关键组蛋白质替换种子节点进行蚁群聚类,克服蚁群算法中因大量拾起放下和重复合并过滤操作而导致准确率和收敛速度过慢的缺陷;接着设计SI（similarity improvement）度量优化拾起放下概率来对节点进行蚁群聚类进而获得聚类数目;最后将关键蛋白质和通过蚁群聚类得到的聚类数目初始化FCM算法,设计隶属度更新策略来优化隶属度的更新,同时提出兼顾类内距和类间距的FCM迭代目标函数,最终利用改进的FCM完成复合物的识别。将FAC-PC算法应用在DIP数据上进行复合物的识别,实验结果表明FAC-PC算法的准确率和召回率较高,能够较准确地识别蛋白质复合物。     

蚁群聚类算法的T-S模糊模型辨识

基于T-S模型,提出一种非线性系统的模型辨识方法。利用蚁群聚类算法来进行结构辨识,确定系统的模糊空间和模糊规则数。在聚类的基础上,利用遗传算法辨识模糊模型的后件加权参数,得到一个精确的模糊模型,从而实现参数辨识。仿真结果验证了该方法的有效性,表明该方法能够实现非线性系统的辨识,辨识精度高,可当作复杂系统建模的一种有效手段。     

一种动态划分的混合连续域蚁群优化算法

连续域蚁群优化算法在处理高维问题时易陷入局部最优,而且收敛速度较慢。针对这些问题,提出了一种改进的连续域蚁群优化算法。该算法将解划分为优解和劣解两部分,并在迭代过程中动态调整优解和劣解的数目。对于优解,利用全局搜索策略进行预处理,这样能提高算法的收敛速度和收敛精度。对于劣解,则利用随机搜索策略进行预处理,这样能扩大搜索范围,增强搜索能力。通过标准测试函数对所提算法进行测试,结果表明改进策略能够有效提高连续域蚁群优化算法的收敛速度并改善解的质量。     

基于蚁群优化算法的凝聚型层次聚类*

传统的凝聚型层次聚类在分裂或合并类时如果没有很好地作出决定,就有可能导致低质量的聚类结果,针对这一缺点,提出一种基于蚁群优化算法的凝聚型层次聚类算法。该算法先利用蚁群优化算法的状态转移规则决定凝聚型层次聚类中下一个将要合并的数据点,再利用信息素更新规则寻找聚类的最优路径,最后获得全局最优的高质量层次聚类结果。该优化算法在人工数据集和UCI数据集上的仿真实验结果表明,相对于传统的聚类算法,该算法的准确率更高,聚类效果更好。     

基于加权模糊C均值聚类的空预器积灰监测研究

电站空预器积灰会严重影响机组运行经济性.提出加权模糊C均值聚类算法对空预器积灰程度进行监测,该方法计算多维样本中每一维数据的标准差,将其作为权重,计算样本与类心之间的加权欧式距离,降低模糊C均值聚类算法对离群点的敏感度.利用人工数据对该方法进行验证,结果表明,相比于传统模糊C均值聚类算法,提出的方法对离群点识别更加准确...     

A fuzzy c-means based hybrid evolutionary approach to the clustering of supply chain

This paper describes the work that adapts group technology and integrates it with fuzzy c-means, genetic algorithms and the tabu search to realize a fuzzy c-means based hybrid evolutionary approach to the clustering of supply chains. The proposed hybrid approach is able to organise supply chain units, transportation modes and work orders into different unit-transportation-work order families. It can determine the optimal clustering parameter, namely the number of clusters, c, and weighting exponent, m, dynamically, and is able to eliminate the necessity of pre-defining suitable values for these clustering parameters. A new fuzzy c-means validity index that takes into account inter-cluster transportation and group efficiency is formulated. It is employed to determine the promise level that estimates how good a set of clustering parameters is. The capability of the proposed hybrid approach is illustrated using three experiments and the comparative studies. The results show that the proposed hybrid approach is able to suggest suitable clustering parameters and near optimal supply chain clusters can be obtained readily.