改进迁移算子的BBO算法及其在PID参数中的优化

针对生物地理学优化（BBO）算法寻优过程中易陷入搜索动力不足、收敛精度不高等问题,提出一种基于改进迁移算子的生物地理学优化算法（IMO-BBO）。在BBO算法基础上,结合“优胜劣汰”的进化思想,将迁移距离作为影响因素对迁移算子进行改进,并用差分策略将不适宜迁移的个体进行替换,以增加算法的局部探索能力。同时为丰富物种的多样性,引入多种群概念。利用IMO-BBO算法分别对13个基准测试函数进行测试,与基于协方差迁移算子和混合差分策略的BBO （CMM-DE/BBO）算法和BBO算法相比,改进算法提高了对全局最优解的搜索能力,在收敛速度和精确度上也都有显著提高;将IMO-BBO算法应用到PID参数整定中,仿真结果表明,所提算法优化后的控制器具有更快的响应速度和更稳定的精度。     

基于人工萤火虫局部决策域的改进生物地理学优化算法

针对生物地理学优化（BBO）算法搜索能力不足的缺点,提出基于萤火虫算法局部决策域策略的改进迁移操作来提算法的全局寻优能力。改进的迁移操作能够在考虑不同栖息地各自的迁入率与迁出率的基础上,进一步利用栖息地之间的相互影响关系。将改进算法应用于12个典型的函数优化问题来测试改进生物地理学优化算法的性能,验证了改进算法的有效性。与BBO、改进BBO（IBBO）、基于差分进化的BBO（DE/BBO）算法的实验结果表明,改进算法提高了算法的全局搜索能力、收敛速度和解的精度。     

基于微分进化的混合生物地理学约束优化算法

针对生物地理学优化算法（biogeography based optimization ,BBO）容易陷入局部最优解的缺点,提出一种基于微分进化（differential evolution ,DE）改进BBO算法的混合生物地理学（BBO‐DE）优化算法。通过有机结合BBO算法的利用能力和DE算法的搜索能力,实现利用能力与搜索能力的平衡;引入基于可行性的约束处理机制,解决传统BBO算法无法求解约束优化的问题。通过选定的8个标准测试函数对改进算法进行仿真测试,测试结果验证了改进算法的可行性和有效性,与基本BBO和DE算法相比,其在最终解的质量和收敛速度上具有明显优势。     

基于迁出地动态选择与自适应迁入策略的BBO算法

Dan Simon用生物地理学的方法和机制来解决工程优化问题,提出了生物地理学优化算法(Biogeography-Based Optimization,BBO)。该算法因其独特的搜索机制和较好的性能在智能优化算法领域得到了广泛的关注。为了进一步提高生物地理学优化算法的全局和局部收索能力,提出了一种基于动态选择迁出地与混合自适应迁入的优化策略,对生物地理学优化算法进行改进,形成一种新的改进型BBO算法。该算法根据进化阶段动态选择待迁出地,并综合当前迁出地和随机迁出地优化迁入策略;同时,设计与适应度相关的变异机制,以增加算法的全局搜索能力。仿真实验结果表明,该算法在全局搜索、收敛速度和收敛精度上均优于对比算法。     

基于改进BBO算法的分数阶PID控制器设计

针对分数阶PID(Fractional-Order Proportional-Integral-Derivative,FOPID)控制器参数整定,提出了一种改进生物地理学优化(Biogeography-Based Optimization,BBO)算法。该算法改进点主要包括:迁移操作中保留精英个体;变异操作中引入差分进化(Dtferential Evolution,ED)算法的变异策略;消除重复样本。仿真结果表明:在分数阶PID控制器参数整定中,与原始的BBO算法、遗传算法(Genetic Algorithm,GA)和粒子群算法(Particle Swarm Optimization,PSO)比较,提出的改进BBO算法具有超调量小、误差小,收敛更快的特点。     

一种改进的生物地理学优化算法

生物地理学优化算法(BBO)作为一种新型的智能算法,在其提出不到十年的时间内受到学界的广泛关注和研究,并显示出了广阔的应用前景。为了提高算法的优化性能,对BBO算法提出一种改进,该算法在将差分优化算法(DE)中的局部搜索策略同BBO算法中的迁移策略相结合的基础上,针对迁移算子和变异算子分别进行改进,提出了二重迁移算子和二重变异算子,使得栖息地个体在进化过程中得到更高的进化概率,从而使得算法的寻优能力得到进一步提升。通过6个高维函数的测试,结果表明该算法在优化高维优化问题时,较其他几种生物地理学优化算法具有更好的收敛性和稳定性。     

引入物种演化的改进生物地理学优化算法

针对生物地理学优化算法(biogeography-based optimization, BBO)易早熟收敛、陷入局部最优的问题,引入物种演化理论提出了改进生物地理学优化算法。该算法将所有栖息地按照物种数量划分为三种地区,并建立协同进化关系,合理地采用区间入侵、区内合作/竞争策略,满足多样性的同时避免了早熟收敛。定义了物种更迭和物种进化两种变异策略,提出的双策略协同变异算子旨在解决变异算子对较优解的破坏。通过CEC2017中的八个基准测试函数与标准BBO及相关改进算法相比,该算法在算法性能、稳定性等方面优于BBO及其他改进算法,且该算法不易被局部最优值所限制。将该算法应用于以最大完工时间为目标的柔性作业车间调度问题(flexible Job-Shop scheduling problem, FJSP)以检验其实际应用价值,实验表明,该算法在解决FJSP上具有一定的有效性。     

基于精英策略和ABBO算法的输电线路故障诊断模型

针对输电线路故障分类问题，提出了一种基于精英策略的生物地理学与算术优化混合算法（ABBO）的输电线路故障诊断模型。首先，为了避免BBO算法的早熟收敛，提出将算术优化算法（AOA）的乘除加减算子代替生物地理学优化算法（BBO）的变异算子以优化特征属性权重；其次，提出将低于精度阈值的非精英个体进行二次变异的精英策略，以保留优质个体的方式提高算法精度；最后，提出一种基于重力的固定半径的近邻检索方式以改善案例推理中存在的不平衡问题。实验证明，与传统的基于BBO、AOA算法的故障诊断模型相比，该模型能够更加准确的识别故障类型。     

生物地理学优化算法理论及其应用研究综述

生物地理学优化算法（Biogeography-Based Optimization,BBO）是Simon提出的一种基于生物地理学理论的新型智能优化算法,具有良好的收敛性和稳定性。从BBO算法提出的背景出发,介绍了算法的基本理论、算法特点以及算法流程。总结了BBO算法的研究进展,包括BBO算法的理论分析、算法的改进、算法与其他优化算法的混合算法以及BBO算法在函数优化、电力系统、图像处理、机器人路径规划以及调度优化等领域的典型应用。对BBO算法有待解决的问题和未来研究方向进行了总结。     

基于差分进化的生物地理学优化算法

针对生物地理学优化算法在实数编码时搜索能力较弱的缺点,提出一种基于差分进化的混合优化算法(BBO/DEs)。通过将差分进化的搜索性与生物地理优化算法的利用性有机结合,以解决原算法在局部搜索时容易出现早熟的问题;并构造一种基于Levy分布的变异方式,确保种群在进化过程中保持多样性;最后通过实验比较,选取了合适的试验策略。利用高维标准测试函数对相关算法进行实验,结果表明该算法能够克服搜索能力不足的缺点,并继承了原算法的快速收敛性能,可以有效兼顾精度与速度的要求。     

Training radial basis function networks using biogeography-based optimizer

Training artificial neural networks is considered as one of the most challenging machine learning problems. This is mainly due to the presence of a large number of solutions and changes in the search space for different datasets. Conventional training techniques mostly suffer from local optima stagnation and degraded convergence, which make them impractical for datasets with many features. The literature shows that stochastic population-based optimization techniques suit this problem better and are reliably alternative because of high local optima avoidance and flexibility. For the first time, this work proposes a new learning mechanism for radial basis function networks based on biogeography-based optimizer as one of the most well-regarded optimizers in the literature. To prove the efficacy of the proposed methodology, it is employed to solve 12 well-known datasets and compared to 11 current training algorithms including gradient-based and stochastic approaches. The paper considers changing the number of neurons and investigating the performance of algorithms on radial basis function networks with different number of parameters as well. A statistical test is also conducted to judge about the significance of the results. The results show that the biogeography-based optimizer trainer is able to substantially outperform the current training algorithms on all datasets in terms of classification accuracy, speed of convergence, and entrapment in local optima. In addition, the comparison of trainers on radial basis function networks with different neurons size reveal that the biogeography-based optimizer trainer is able to train radial basis function networks with different number of structural parameters effectively.

     

Emergency railway wagon scheduling by hybrid biogeography-based optimization

Railway transportation plays an important role in many disaster relief and other emergency supply chains. Based on the analysis of several recent disaster rescue operations in China, the paper proposes a mathematical model for emergency railway wagon scheduling, which considers multiple target stations requiring relief supplies, source stations for providing supplies, and central stations for allocating railway wagons. Under the emergency environment, the aim of the problem is to minimize the weighted time for delivering all the required supplies to the targets. For efficiently solving the problem, we develop a new hybrid biogeography-based optimization (BBO) algorithm, which uses a local ring topology of population to avoid premature convergence, includes the differential evolution (DE) mutation operator to perform effective exploration, and takes some problem-specific mechanisms for fine-tuning the search process and handling the constraints. Computational experiments show that our algorithm is robust and scalable, and outperforms some state-of-the-art heuristic algorithms on a set of problem instances.     

一种粒子群和改进自适应差分进化混合算法及在生产调度中的应用

差分进化算法是一类基于种群的启发式全局搜索技术,但传统的差分进化算法存在停滞现象,容易使算法收敛停止。虽然之后出现了各种版本的自适应差分进化算法,但没有考虑到当代个体的适应值是否向着最优个体的适应值逼近,因此本文提出了一种新型的自适应差分进化算法FMDE。考虑到粒子群算法和差分进化算法类似,为了充分发挥两种算法的特点,提出了自适应差分进化和粒子群的混合算法PSO_FMDE;最后采用测试数据集对性能进行分析。实验结果表明,该算法根据进化过程中的搜索进度自适应地确定变异率,使算法易于跳出局部最优解,以提高全局搜索能力。PSO_FMDE算法较单一算法而言,性能更优,更易于靠近全局最优解。     

A fast BP networks with dynamic sample selection for handwritten recognition

Training time of traditional multilayer perceptrons (MLPs) using back-propagation algorithm rises seriously with the problem scale. For multi-class problems, the convergence ratio is very low for training MLPs. The huge time-consuming and low convergence ratio greatly restricts the applications of MLPs on problems with tens and thousands of samples. To deal with these disadvantages, this paper proposes a fast BP network with dynamic sample selection (BPNDSS) method which can dynamically select the samples containing more contribution to the variation of the decision boundary for training after each iteration epoch. The proposed BPNDSS can significantly increase the training speed by only selecting a small subset of the whole samples. Moreover, two kinds of modular single-hidden-layer approaches are adopted to decompose a multi-class problem into multiple binary-class sub-problems, which result in the high rate of convergence. The experiments on Letter and MNIST handwritten recognition database show the effectiveness and the efficiency of BPNDSS. Moreover, BPNDSS results in comparable classification performance to the convolutional neural networks (CNNs), support vector machine, Adaboost, C4.5, and nearest neighbour algorithms. To further demonstrate the training speed improvement of the dynamic sample selection approach on large-scale datasets, we modify CNN to propose a dynamic sample selection CNN (DynCNN). Experiments on Image-Net dataset illustrate that DynCNN can result in similar performance to CNN, but consume less training time.     

A hybrid approach of differential evolution and artificial bee colony for feature selection

“Dimensionality” is one of the major problems which affect the quality of learning process in most of the machine learning and data mining tasks. Having high dimensional datasets for training a classification model may lead to have “overfitting” of the learned model to the training data. Overfitting reduces generalization of the model, therefore causes poor classification accuracy for the new test instances. Another disadvantage of dimensionality of dataset is to have high CPU time requirement for learning and testing the model. Applying feature selection to the dataset before the learning process is essential to improve the performance of the classification task. In this study, a new hybrid method which combines artificial bee colony optimization technique with differential evolution algorithm is proposed for feature selection of classification tasks. The developed hybrid method is evaluated by using fifteen datasets from the UCI Repository which are commonly used in classification problems. To make a complete evaluation, the proposed hybrid feature selection method is compared with the artificial bee colony optimization, and differential evolution based feature selection methods, as well as with the three most popular feature selection techniques that are information gain, chi-square, and correlation feature selection. In addition to these, the performance of the proposed method is also compared with the studies in the literature which uses the same datasets. The experimental results of this study show that our developed hybrid method is able to select good features for classification tasks to improve run-time performance and accuracy of the classifier. The proposed hybrid method may also be applied to other search and optimization problems as its performance for feature selection is better than pure artificial bee colony optimization, and differential evolution.     

基于混合凸迁移和趋优柯西变异的对偶生物地理学优化算法

通过分析生物地理学优化算法(BBO)性能的不足,提出了一种基于混合凸迁移和趋优柯西变异的对偶生物地理学优化算法(DuBBO).在迁移算子中,采用动态的混合凸迁移算子,使算法能够快速地向最优解方向收敛;在变异机制中,采用趋优变异策略,并加入了柯西分布随机数帮助算法跳出局部最优解;最后将对偶学习策略集成到算法中,加快了算法收敛速度并提升了搜索能力.在23个benchmark函数上的实验结果证明了提出的三种改进策略的有效性和必要性.最后将DuBBO与BBO以及另外六种优秀的改进算法进行对比.实验结果表明,DuBBO在整体性能上最好、收敛速度更快、收敛精度更高.     

一种自适应差分演化算法

差分演化算法是一类基于种群的启发式全局搜索技术,对于实值参数的优化具有很强的鲁棒性。为了提高差分演化算法的寻优速度、克服启发式算法常见的早熟收敛问题,提出了一种自适应的方法来调整控制参数。实验表明,算法的收敛速度和寻优能力得到很大的提高。     

Determination of relative agrarian technical efficiency by a dynamic over-sampling procedure guided by minimum sensitivity

In this paper, a dynamic over-sampling procedure is proposed to improve the classification of imbalanced datasets with more than two classes. This procedure is incorporated into a Hybrid algorithm (HA) that optimizes Multi Layer Perceptron Neural Networks (MLPs). To handle class imbalance, the training dataset is resampled in two stages. In the first stage, an over-sampling procedure is applied to the minority class to partially balance the size of the classes. In the second, the HA is run and the dataset is over-sampled in different generations of the evolution, generating new patterns in the minimum sensitivity class (the class with the worst accuracy for the best MLP of the population). To evaluate the efficiency of our technique, we pose a complex problem, the classification of 1617 real farms into three classes (efficient, intermediate and inefficient) according to the Relative Technical Efficiency (RTE) obtained by the Monte Carlo Data Envelopment Analysis (MC-DEA). The multi-classification model, named Dynamic Smote Hybrid Multi Layer Perceptron (DSHMLP) is compared to other standard classification methods with an over-sampling procedure in the preprocessing stage and to the threshold-moving method where the output threshold is moved toward inexpensive classes. The results show that our proposal is able to improve minimum sensitivity in the generalization set (35.00%) and obtains a high accuracy level (72.63%).     

基于混合生物地理学优化的聚类算法

聚类分析是数据挖掘的重要任务之一,而具有易早熟与收敛速度慢等缺陷的传统生物地理优化算法(Biogeography-Based Optimization, BBO)很难满足具有NP(Non-deterministic Polynomial)性质的复杂聚类问题需求,于是提出了一种基于混合生物地理学优化的聚类算法(Mixed Biogeography-Based Optimization, MBBO),该算法构造了一个基于梯度下降局部最优贪心搜索的新迁移算子,以聚类目标函数值作为个体适应度进行数据集内隐簇结构寻优。通过在4个标准数据集(Iris、Wine、Glass与Diabetes)的实验,结果表明MBBO算法相对于传统的优化算法具有更好的优化能力和收敛度,能发现更高质量的簇结构模式。     

混合波动差分进化算法*

针对传统差分进化算法在处理复杂优化问题时存在易陷入局部最优解和求解精度低的缺陷,提出了混合波动差分进化算法。该算法预先设置两组配置参数,并依据混合系数的区分,依次选择每组中的交叉因子和相关参数构成波动算子生成变异率用于新算法中;同时为了加快收敛速度,采用选中随机向量中适应度值最优的向量作为基向量,避免算法寻优的盲目性。对一系列经典Benchmark函数的测试,并将实验结果与其他算法进行比较,证明了本算法的收敛速度与优化质量均显著改善。