面向入侵检测的基于多目标遗传算法的特征选择

针对刻画网络行为的特征集中存在着不相关或冗余特征,从而导致入侵检测性能下降的问题,本文提出了一种基于多目标遗传算法的特征选择方法,将入侵检测中的特征选择问题视为多目标优化问题来处理。实验结果表明,该方法能够实现检测精度与检测算法复杂性的均衡优化,在显著提高检测算法效率的同时,检测精度也有所提高。     

极限学习机多目标模型选择研究

为了克服极限学习机输入权重与偏置的随机性对模型泛化能力的负面影响,提出一种基于多目标优化的极限学习机模型选择方法将极限学习机模型选择视为一个多目标全局优化问题,可将泛化误差和输出权重的模作为优化目标;为加快优化速度,引入极限学习机的快速留一法误差估计指代泛化误差,并考虑到优化目标间的互斥性,最终采用多目标综合学习粒子群算法寻找非支配解.通过5个UCI回归数据集上的仿真结果表明,与常用极限学习机模型选择方法相比,改进方法均取得更低的预测误差,同时网络结构更加紧凑.     

基于多点非均匀变异的多目标极值优化算法研究

多目标进化算法因其在解决含有多个矛盾目标函数的多目标优化问题中的强大处理能力,正受到越来越多的关注与研究。极值优化作为一种新型的进化算法,已在各种离散优化、连续优化测试函数以及工程优化问题中得到了较为成功的应用,但有关多目标EO算法的研究却十分有限。本文将采用Pareto优化的基本原理引入到极值优化算法中,提出一种求解连续多目标优化问题的基于多点非均匀变异的多目标极值优化算法。通过对六个国际公认的连续多目标优化测试函数的仿真实验结果表明：本文提出算法相比NSGA-II、 PAES、SPEA和SPEA2等经典多目标优化算法在收敛性和分布性方面均具有优势。     

基于演化算法实现多目标优化的岛屿迁徙模型

多目标演化算法(MOEA)利用种群策略，尽可能地找出多目标问题的Pareto最优集供决策者选择，为决策者提供了更大的选择余地，与其它传统的方法相比有了很大的改进．但提供大量选择的同时，存在着不能为决策者提供一定的指导性信息，不能反映决策者的偏好，可扩展性差等问题．本文提出了一个新的多目标演化算法(MOEA)计算模型…岛屿迁徙模型，该模型体现了一种全新的多目标演化优化的求解思想，对多目标优化问题的最优解集作了新的定义．数值试验结果表明，岛屿迁徙模型在求解MOP时有效地解决了以上问题，并且存在进一步改进的潜力．     

基于混沌多目标粒子群优化算法的云服务选择

随着云计算环境中各种服务数量的急剧增长,如何从功能相同或相似的云服务中选择满足用户需求的服务成为云计算研究中亟待解决的关键问题。为此,建立带服务质量约束的多目标服务组合优化模型,针对传统多目标粒子群优化(MOPSO)算法中解的多样性差、易陷入局部最优等缺点,设计基于混沌多目标粒子群优化(CMOPSO)算法的云服务选择方法。采用信息熵理论来维护非支配解集,以保持解的多样性和分布的均匀性。当种群多样性丢失时,引入混沌扰动机制,以提高种群多样性和算法全局寻优能力,避免陷入局部最优。实验结果表明,与MOPSO算法相比,CMOPSO算法的收敛性和解集多样性均得到改善,能够更好地解决云计算环境下服务动态选择问题。     

一个多目标优化演化算法的收敛性分析框架

由于演化算法求解多目标优化问题所得结果是一个优化解集——Pareto最优集,而现有的演化算法收敛性分析只适合针对单目标优化问题的单个。用有限马尔科夫链给出了演化算法求解多目标优化问题的收敛性分析框架,并给出了一个分析实例。     

Ensemble Variable Selection for Naive Bayes to Improve Customer Behaviour Analysis

Executing customer analysis in a systemic way is one of the possible solutions for each enterprise to understand the behavior of consumer patterns in an efficient and in-depth manner. Further investigation of customer patterns helps the firm to develop efficient decisions and in turn, helps to optimize the enterprise’s business and maximizes consumer satisfaction correspondingly. To conduct an effective assessment about the customers, Naive Bayes(also called Simple Bayes), a machine learning model is utilized. However, the efficacious of the simple Bayes model is utterly relying on the consumer data used, and the existence of uncertain and redundant attributes in the consumer data enables the simple Bayes model to attain the worst prediction in consumer data because of its presumption regarding the attributes applied. However, in practice, the NB premise is not true in consumer data, and the analysis of these redundant attributes enables simple Bayes model to get poor prediction results. In this work, an ensemble attribute selection methodology is performed to overcome the problem with consumer data and to pick a steady uncorrelated attribute set to model with the NB classifier. In ensemble variable selection, two different strategies are applied: one is based upon data perturbation (or homogeneous ensemble, same feature selector is applied to a different subsamples derived from the same learning set) and the other one is based upon function perturbation (or heterogeneous ensemble different feature selector is utilized to the same learning set). Furthermore, the feature set captured from both ensemble strategies is applied to NB individually and the outcome obtained is computed. Finally, the experimental outcomes show that the proposed ensemble strategies perform efficiently in choosing a steady attribute set and increasing NB classification performance efficiently.     

基于互信息的软测量变量选择

针对软测量建模中的变量选择问题,提出了一种结合信息论中最大熵和互信息的方法。该方法采用最大熵原理,对软测量中各辅助变量和主导变量的概率分布进行估计,得到主导变量和各辅助变量间的互信息,这些互信息间接地反映了主导变量和各辅助变量间的相关性,包括线性相关和非线性相关。然后产生随机样本并计算和主导变量间的互信息,重复多次该过程就可以得到一个无关变量和主导变量间的互信息样本。用T检验寻找一个阈值作为判断相关性的标准。对于互信息小于阈值的变量作不相关变量处理,并结合测试效果筛选出最佳的软测量辅助变量。仿真结果证明,基于互信息的软测量变量选择方法具有直观、简单实用和可靠性高的优点,并且有效地改善了模型的估计精度。     

Deep Learning Test Optimization Method Using Multi-objective Optimization

With the rapid development of deep learning technology, research on its quality assurance is raising more attention. Meanwhile, it is no longer difficult to collect test data owing to the mature sensor technology, but it costs a lot to label the collected data. To reduce the cost of labeling, the existing studies attempt to select a test subset from the original test set. The test subset, however, only ensures that the overall accuracy (the accuracy of the target deep learning model on all test inputs of the test set) of the test subset is similar to that of the original test set; it cannot maintain other test properties similar to those of the original test set. For example, it cannot fully cover all kinds of test input in the original test set. This study proposes a method based on multi-objective optimization called Deep Multi-Objective Selection (DMOS). It firstly analyzes the data distribution of the original test set by Hierarchical Density-Based Spatial Clustering of Applications with Noise (HDBSCAN). Then, it designs multiple optimization objectives given the characteristics of the clustering results and then carries out multi-objective optimization to find out the appropriate selection solution. Massive experiments are carried out on eight pairs of classic deep learning test sets and models. The results reveal that the best test subset selected by the DMOS method (the test subset corresponding to the Pareto optimal solution with the best performance) can not only cover more test input categories in the original test set but also estimate the accuracy of each test input category extremely close to that of the original test set. Meanwhile, it can also ensure that the overall accuracy and test adequacy are close to those of the original test set: the average error of the overall accuracy estimation is only 1.081%, which is 0.845% lower than that of Practical ACcuracy Estimation (PACE), an improvement of 43.87%. The average error of the accuracy estimation of each test input category is only 5.547%, which is 2.926% less than that of PACE, an improvement of 34.53%. The average estimation error of the five test adequacy measures is only 8.739%, which is 7.328% lower than that of PACE, an improvement of 45.61%.     

采用多目标优化的深度学习测试优化方法

随着深度学习技术的快速发展,对其质量保障的研究也逐步增多.传感器等技术的迅速发展,使得收集测试数据变得不再困难,但对收集到的数据进行标记却需要花费高昂的代价.已有工作尝试从原始测试集中筛选出一个测试子集以降低标记成本,这些测试子集保证了与原始测试集具有相近的整体准确率(即待测深度学习模型在测试集全体测试输入上的准确率),但却不能保证在其他测试性质上与原始测试集相近.例如,不能充分覆盖原始测试集中各个类别的测试输入.提出了一种基于多目标优化的深度学习测试输入选择方法 DMOS(deep multi-objectiveselection),其首先基于HDBSCAN(hierarchicaldensity-basedspatialclusteringofapplicationswith noise)聚类方法初步分析原始测试集的数据分布,然后基于聚类结果的特征设计多个优化目标,接着利用多目标优化求解出合适的选择方案.在8组经典的深度学习测试集和模型上进行了大量实验,结果表明, DMOS方法选出的最佳测试子集(性能最好的Pareto最优解对应的测试子集)不仅能够覆盖原始测试集中更多的测试输入类别...     

Multi-objective genetic algorithm based approaches for mining optimized fuzzy association rules

Association rules form one of the most widely used techniques to discover correlations among attribute in a database. So far, some efficient methods have been proposed to obtain these rules with respect to an optimal goal, such as: to maximize the number of large itemsets and interesting rules or the values of support and confidence for the discovered rules. This paper first introduces optimized fuzzy association rule mining in terms of three important criteria; strongness, interestingness and comprehensibility. Then, it proposes multi-objective Genetic Algorithm (GA) based approaches for discovering these optimized rules. Optimization technique according to given criterion may be one of two different forms; The first tries to determine the appropriate fuzzy sets of quantitative attributes in a prespecified rule, which is also called as certain rule. The second deals with finding both uncertain rules and their appropriate fuzzy sets. Experimental results conducted on a real data set show the effectiveness and applicability of the proposed approach.     

多目标优化的一类模拟退火算法

多目标优化是运筹学中的重要研究课题,但迄今仍缺少高效的优化技术。通过对搜索操作和参数的合理设置,提出了一类求解多目标优化问题Pareto最优解的高效模拟退火算法。基于典型算例的数值仿真验证了算法的有效性。     

Critical Technology in Solving Multi-objective Particle Swarm Optimization Algorithm

As is well known, in MOPSO （multi-objective particle swarm optimization）, it is of great significance on the convergence and diversity of final solutions that finding out a feasible global best guide for each particle of the current swarm. In this paper, an improved method for determining the best local guide in MOPSO is proposed, where the Pareto archive is used to store the non-dominated solutions. In addition, the concept of crowding distance, which is applied to maintain the size of Pareto archive, has greatly improved the diversity of swarm and adequate distribution of Pareto fronts. Finally, a problem including two different objectives is computed, and the result is described in the last part of this paper. From the experimental results, it is shown that the simulation effect is highly accurate.     

具有模糊控制变量的多元线性回归

多元线性回归被广泛用于预测。回归式反映了响应变量和预测变量间的线性关系。将模糊集理论引入多元线性回归中,通过模糊控制变量,可以得出更符合实际,也更容易为人所理解的回归模型。针对真实数据的实验表明,具有模糊控制变量的线性回归可以解决一类复杂的回归问题。     

Multi-objective optimization for parameter selection and characterization of optical flow methods

Optical flow methods are among the most accurate techniques for estimating displacement and velocity fields in a number of applications that range from neuroscience to robotics. The performance of any optical flow method will naturally depend on the configuration of its parameters, and for different applications there are different trade-offs between the corresponding evaluation criteria (e.g. the accuracy and the processing speed of the estimated optical flow). Beyond the standard practice of manual selection of parameters for a specific application, in this article we propose a framework for automatic parameter setting that allows searching for an approximated Pareto-optimal set of configurations in the whole parameter space. This final Pareto-front characterizes each specific method, enabling proper method comparison and proper parameter selection. Using the proposed methodology and two open benchmark databases, we study two recent variational optical flow methods. The obtained results clearly indicate that the method to be selected is application dependent, that in general method comparison and parameter selection should not be done using a single evaluation measure, and that the proposed approach allows to successfully perform the desired method comparison and parameter selection.     

Single and Multi-objective Evolutionary Algorithms for the Coordination of Serial Manufacturing Operations

This paper focuses on a typical problem arising in serial production, where two consecutive departments must sequence their internal work, each taking into account the requirements of the other one. Even if the considered problem is inherently multi-objective, to date the only heuristic approaches dealing with this problem use single-objective formulations, and also require specific assumptions on the objective function, leaving the most general case of the problem open for innovative approaches. In this paper, we develop and compare three evolutionary algorithms for dealing with such a type of combinatorial problems. Two algorithms are designed to perform directed search by aggregating the objectives of each department in a single fitness, while a third one is designed to search for the Pareto front of non-dominated solutions. We apply the three algorithms to considerably complex case studies derived from industrial production of furniture. Firstly, we validate the effectiveness of the proposed genetic algorithms considering a simple case study for which information about the optimal solution is available. Then, we focus on more complex case studies, for which no a priori indication on the optimal solutions is available, and perform an extensive comparison of the various approaches. All the considered algorithms are able to find satisfactory solutions on large production sequences with nearly 300 jobs in acceptable computation times, but they also exhibit some complementary characteristics that suggest hybrid combinations of the various methods.     

多目标优化特征选择研究综述

特征选择是模式识别领域中有效的降维方法,当特征选择涉及到的多个目标彼此冲突,难以平衡时,将特征选择视为多目标优化问题是时下的研究热点。为方便研究者系统地了解多目标特征选择领域的研究现状和发展趋势,对多目标特征选择方法进行综述。阐明了特征选择和多目标优化的本质;根据多目标优化方法的区别和特点,重点对比剖析各类多目标优化特征选择方法的优劣势;讨论现有多目标优化特征选择研究方法存在的问题以及对未来的展望。     

求解多目标优化问题的新遗传算法

给出了求解多目标优化问题的一种新解法。定义了多目标优化问题的非劣方向,设计了方向杂交算子和简单的变异算子。标准算例的计算机仿真结果表明,新算法可以快速地找到一组范围广、分布均匀且数量充足的Pareto最优解。     

城市交通过饱和状态下干线信号的多目标仿真优化研究

针对城市交通过饱和状态下的干线信号优化问题,分析了交通控制目标对车辆排队的影响,提出以绿信比、相序、相位差和周期为优化参数,以车辆平均时延、系统平均排队-车道长度比和系统通行能力为优化目标的交通信号仿真优化模型。构建了优化模型的实施框架,该框架采用自主构建的微观交通仿真环境来获取信号方案评价指标,改进多目标优化算法NSGAII中的重复个体问题,完成对干线各交叉口信号配时方案的同时优化。最后,利用采集的交通数据对由3个交叉口组成的干线进行实例验证,验证结果表明,在过饱和状态下,所提出的信号优化方法不仅可以有效控制车辆排队长度,均衡车辆分布,同时在系统通行能力、车均时延方面表现更佳。     

变邻域杂草算法在多目标柔性作业车间调度中的应用*

针对最小化最大完工时间、总机床负荷最小及最大负载最小的多目标柔性作业车间调度问题,提出了变邻域杂草算法。首先,基于随机键编码方式,构造单链杂草,实现了杂草空间到调度空间的映射。其次,迭代后期执行变邻域搜索,对精英杂草局部深入挖掘,并通过反解码过程将调度空间的优良解反馈回杂草空间。对比实验表明,变邻域杂草算法在求解多目标基准问题时,非劣解集中解的数量和质量有一定优势。变邻域杂草算法是求解多目标柔性作业车间调度问题的有效方法。