细菌觅食优化算法的研究与应用

细菌觅食优化算法是进化算法家族的新成员。首先对细菌觅食优化算法的三大主要操作：趋向性、复制和迁徙操作的基本原理及流程进行介绍,然后对算法求解优化问题的设计步骤进行分析,接着探讨算法的改进和应用,最后指出细菌觅食优化算法的未来研究方向。     

基于细菌觅食的改进蚁群算法

蚁群算法是模仿蚂蚁觅食行为的一种新的仿生学智能优化算法。针对其收敛速度慢和易陷入局部最优的不足,将细菌觅食算法和蚁群算法相结合,提出一种细菌觅食 蚁群算法。在蚁群算法迭代过程中,引入细菌觅食算法的复制操作,以加快算法的收敛速度;引入细菌觅食算法的趋向操作,以增强算法的全局搜索能力。通过经典的旅行商问题和函数优化问题测试表明,细菌觅食 蚁群算法在寻优能力、可靠性、收敛效率和稳定性方面均优于基本蚁群算法及两种改进蚁群算法。     

改进的细菌觅食优化算法求解0-1背包问题

细菌觅食优化算法作为一种新兴的智能优化算法,一般用来解决连续域的问题。为了解决离散域问题,提出了一种改进的细菌觅食优化算法。采用线性递减的思想和随机的游动长度代替固定步长和随机游动方向,改进了趋向性操作方案,并将其应用于解决0-1背包问题。将改进的细菌觅食优化算法与遗传算法、离散粒子群优化算法及基本的离散化细菌觅食优化算法分别在小规模和大规模的0-1背包问题上进行了仿真比较,表明了改进的细菌觅食优化算法能取得较好的效果,寻优能力强。     

基于模拟退火策略的细菌觅食优化算法

针对标准细菌觅食优化算法(BFOA)求解精度不高、稳定性较差、容易陷入局部极值的问题,提出了一种基于模拟退火策略的细菌觅食优化算法(SA-BFO)。该算法在趋向操作完成后,采用模拟退火策略对全局最优个体进行优化,提高算法的优化精度和稳定性,利用模拟退火算法的概率突跳性来避免陷入局部极值。仿真实验结果表明,改进算法比标准细菌觅食优化算法具有较高的优化性能。     

新型群智能优化算法综述

传统群智能算法在解决复杂实际多目标优化问题中存在不足,近年来学者提出诸多新型群智能算法,适用性强,在求解复杂实际问题中取得了较好的实验效果。以算法提出时间为主线,对新型群智能算法中细菌觅食优化算法、混合蛙跳算法、人工蜂群算法、萤火虫算法、布谷鸟搜索、果蝇优化算法和头脑风暴优化算法的改进及应用进行分析和综述,并对群智能算法未来的研究发展方向进行了探讨。     

含分布式发电的改进BFO算法配电网无功优化

在含分布式电源的电网无功优化研究中,为了更有效地提高配电网性能,提出了一种改进细菌觅食算法(CP-BFO).以电网网损最小、负荷节点电压和发电机的无功出力约束作为综合目标函数,采用细菌觅食算法,在聚焦操作中引入粒子群变异算子,使算法具有良好的全局搜索能力,提高了算法的寻优效率.同时利用混沌原理对改进的细菌觅食算法的参数进行自适应调节,改善了算法的收敛性能.通过节点系统的仿真表明,CP-BFO算法在提高含分布式电源的智能电网电压质量与减少功率损耗的优化过程中具有可行性和有效性.     

一种细菌觅食算法的改进及其应用

针对原有细菌觅食算法收敛速度慢、计算量大的问题,首先通过改进细菌种群大小、细菌运动步长、引进迭代终止条件改进原有细菌觅食算法,然后将其应用到支持向量机的参数优化上。实验以Iris标准测试数据集为依托,以高斯核支持向量机中核参数γ和惩罚因子C为优化对象,分析了遗传算法、粒子群算法、原有的和改进后的细菌觅食算法的寻优性能,验证了将改进后的细菌觅食算法应用到支持向量机参数选择上具有优越性。     

基于细菌觅食优化算法的WSNs节点部署策略

为了提高传感器节点的有效覆盖率,提出了一种基于细菌觅食优化(BFO)算法的节点部署策略。以网络覆盖率为目标函数,在细菌觅食算法的趋向操作过程中,引入碰壁策略,对细菌初始位置进行优化,从而提高算法的收敛速度。算法中的每个细菌都代表一只传感器,多个细菌组成的一个菌落代表一种传感器的部署方案。算法以菌落为单位做复制操作和迁徙操作,按照菌落适应度值大小选出较为优越的部署方案。通过仿真实验,分析了参数对算法性能的影响,并与其他方法的优化结果进行比较,结果表明:该算法有效地提高了传感器节点覆盖率。     

基于细菌觅食机理改进粒子群算法的研究

粒子群算法与细菌觅食算法在优化问题中均体现了较好的性能,但由于各自特定的进化机制,也都存在缺点。粒子群优化（PSO）算法在优化过程中过快陷入局部极值,为了避免这个缺陷,提出了一种新的混合算法。通过PSO算法完成整个空间的全局搜索,通过细菌觅食算法（BFOA）中的趋向性运动算子完成局部搜索的功能,再通过典型函数进行测试,结果表明新算法可以有效弥补细菌觅食算法速度不快和粒子群算法精度不高的缺陷,同时部分地避免了局部收敛的问题,从而适用于解决复杂函数的优化问题。     

多目标细菌觅食优化算法*

传统的细菌觅食优化算法仅针对单目标优化问题寻优。为进一步发掘细菌群体智能在多目标优化问题中的寻优优势,提出了改进的多目标细菌觅食优化算法。在个体间互不支配时给出归一化的择优策略;引入差分思想完成复制操作,提高种群的多样性;采用栅格划分法进行迁徙操作,提高解集的分散性。同时使用外部集存放当前找到的非支配解,并不断对外部集进行优化。通过对多个标准函数进行测试并与其他几种算法的对比结果表明,所提出的多目标细菌觅食优化算法在解的收敛性和分散性指标上都有一定提升,能够有效解决多目标优化问题。     

一种改进细菌觅食优化算法及其在软测量建模中的应用

针对软测量建模中模型参数的优化需求,在分析细菌觅食优化算法(BFOA)和粒子群优化(PSO)算法的基础上,将二者有机结合,提出了一种新型细菌觅食粒子群混合优化算法(BSOA)。该算法将PSO粒子移动的思想引入BFOA,有效解决了BFOA趋向性操作中细菌位置更新的盲目性。将其分别用于典型函数的寻优与成品油研究法辛烷值最小二乘支持向量机(LSSVM)模型参数的优化,仿真结果表明:该方法有效增强了算法的全局寻优能力与收敛速度,并在一定程度上改善了模型的预测精度与泛化能力。     

一种基于细菌觅食优化算法的舌体分割算法

针对医学舌体数字图像的准确分割,提出了一种基于细菌觅食优化算法(BFOA) 和 Snake 活动轮廓模型相组合的舌体分割算法。首先,以信息熵与 Kapur 算法相结合作为自适 应函数来改进 BFOA 算法,通过改进的 BFOA 算法计算舌体图像的最佳图像二值化阈值,并将 舌体图像二值化;然后,利用舌体图像的对称性提取舌体的关键边缘点,并基于 B-样条插值算 法由关键点集合插值得到闭合的 B-样条曲线,作为 Snake 模型的初始轮廓;最后,通过 Snake 模型计算求解,即可准确提取舌体的轮廓曲线。实验结果表明,改进算法能够高精度地分割出 舌体图像,并能消除基本 Snake 模型在初始轮廓曲线选取中存在的人机交互难题,实现了舌体 图像的自动分割。     

改进细菌觅食算法求解车间作业调度问题*

针对细菌觅食算法（BFOA）求解高维优化问题时容易陷入局部最优和早熟的问题,引入自适应步长及差分进化算子,并将改进算法用于车间作业调度问题（JSP）中。求解时,设计了一种编码转换方案,从而无须修改BFOA运算规则即可实现对JSP的寻优;同时,采用空闲时间片段优化策略降低了调度问题的复杂性。仿真实验表明,该算法能够跳出局部最优,避免了早熟的问题,调度结果优于原始细菌觅食算法和离散粒子群算法。     

Study of differential search algorithm based automatic generation control of an interconnected thermal-thermal system with governor dead-band

An attempt has been made to the effective application of a recently introduced, powerful optimization technique called differential search algorithm (DSA), for the first time to solve load frequency control (LFC) problem in power system. In this paper, initially, DSA optimized classical PI/PIDF controller is implemented to an identical two-area thermal-thermal power system and then the study is extended to two more realistic power systems which are widely used in the literature. To assess the usefulness of DSA, three enhanced competitive algorithms namely comprehensive learning particle swarm optimization (CLPSO), ensemble of mutation and crossover strategies and parameters in differential evolution (EPSDE), and success history based DE (SHADE) are studied in this paper. Moreover, the superiority of proposed DSA optimized PI/PID/PIDF controller is validated by an extensive comparative analysis with some recently published meta-heuristic algorithms such as firefly algorithm (FA), bacteria foraging optimization algorithm (BFOA), genetic algorithm (GA), craziness based particle swarm optimization (CRPSO), differential evolution (DE), teaching-learning based optimization (TLBO), particle swarm optimization (PSO), and quasi-oppositional harmony search algorithm (QOHSA). A case of robustness and sensitivity analysis has been performed for the concerned test system under parametric uncertainty and random load perturbation. Furthermore, to demonstrate the efficacy of proposed DSA, the system nonlinearities like reheater of the steam turbine and governor dead band are included in the system modeling. The extensive results presented in this article demonstrate that proposed DSA can effectively improve system dynamics and may be applied to real-time LFC problem.     

Optimal foraging algorithm for global optimization

An optimization algorithm, inspired by the animal Behavioral Ecology Theory—Optimal Foraging Theory, named the Optimal Foraging Algorithm (OFA) has been developed. As a new stochastic search algorithm, OFA is used to solve the global optimization problems following the animal foraging behavior. During foraging, animals know how to find the best pitch with abundant prey; in establishing OFA, the basic operator of OFA was constructed following this foraging strategy. During foraging, an individual of the foraging swarms obtained more opportunities to capture prey through recruitment; in OFA the recruitment was adopted to ensure the algorithm has a higher chance to receive the optimal solution. Meanwhile, the precise model of prey choices proposed by Krebs et al. was modified and adopted to establish the optimal solution choosing strategy of OFA. The OFA was tested on the benchmark functions that present difficulties common to many global optimization problems. The performance comparisons among the OFA, real coded genetic algorithms (RCGAs), Differential Evolution (DE), Particle Swarm Optimization (PSO) algorithm, Bees Algorithm (BA), Bacteria Foraging Optimization Algorithm (BFOA) and Shuffled Frog-leaping Algorithm (SFLA) are carried out through experiments. The parameter of OFA and the dimensions of the multi-functions are researched. The results obtained by experiments and Kruskal-Wallis test indicate that the performance of OFA is better than the other six algorithms in terms of the ability to converge to the optimal or the near-optimal solutions, and the performance of OFA is the second-best one from the view of the statistical analysis.     

Petri网的正向推理算法

提出了一种建立在petri网的基本结构上的形式化正向推理算法,通过建立petri网的关联矩阵、标识向量和激发向量,将petri网与矩阵运算结合,可以在petri网模型中抽取一个子模型,从而把一个大的、复杂的系统转化为一个只与问题相关的小的系统来处理。该算法充分利用了petri网的并行处理能力,缩小了后续应用的范围,加速了后续应用的效率。     

正交遗传算法在网络优化设计中的应用

利用正交实验法的全局思想,提出一种采用多点正交交换的遗传算法。算法通过正交表安排遗传算法的交换运算,并在所产生的多个子代中选择适应度大的个体进入下一代进化,这样既加快了算法的收敛速度又保证了种群的多样性。并将该算法应用在计算机网络的容量分配与路由选择优化上。实验证明,该算法较之传统遗传算法,在种群规模较小的情况下,仍然可以以较少的搜索次数,收敛到近似最优解。     

A novel hybrid gravitational search and pattern search algorithm for load frequency control of nonlinear power system

In this paper, a hybrid gravitational search algorithm (GSA) and pattern search (PS) technique is proposed for load frequency control (LFC) of multi-area power system. Initially, various conventional error criterions are considered, the PI controller parameters for a two-area power system are optimized employing GSA and the effect of objective function on system performance is analyzed. Then GSA control parameters are tuned by carrying out multiple runs of algorithm for each control parameter variation. After that PS is employed to fine tune the best solution provided by GSA. Further, modifications in the objective function and controller structure are introduced and the controller parameters are optimized employing the proposed hybrid GSA and PS (hGSA-PS) approach. The superiority of the proposed approach is demonstrated by comparing the results with some recently published modern heuristic optimization techniques such as firefly algorithm (FA), differential evolution (DE), bacteria foraging optimization algorithm (BFOA), particle swarm optimization (PSO), hybrid BFOA-PSO, NSGA-II and genetic algorithm (GA) for the same interconnected power system. Additionally, sensitivity analysis is performed by varying the system parameters and operating load conditions from their nominal values. Also, the proposed approach is extended to two-area reheat thermal power system by considering the physical constraints such as reheat turbine, generation rate constraint (GRC) and governor dead band (GDB) nonlinearity. Finally, to demonstrate the ability of the proposed algorithm to cope with nonlinear and unequal interconnected areas with different controller coefficients, the study is extended to a nonlinear three unequal area power system and the controller parameters of each area are optimized using proposed hGSA-PS technique.     

基于改进聚类算法构建智慧医院的研究与实践

针对智慧医院缺乏有效的智能辅助诊疗应用问题,提出一种改进聚类算法来设计与实践智慧医院的相关医疗应用,实现诊疗辅助。该算法结合一种改进的遗传算法和网络中心数学模型对初始中心进行优化,先用一种改进的遗传算法获得文档集合的近似最优聚簇数K,然后采用网络中心与重心数学模型来获得优化的初始聚类中心点,有效解决了算法对初始聚类中心的敏感性,取得了较好的实验结果。在实践应用阶段结合不同的医疗业务场景设计制定不同的应用规则模型,并通过智能检查预约时效分析、输血质量智能评价、手术风险预测分析、辅助诊断推荐等实践应用检测该算法的运行效果,取得了良好的运用结果。