MPBOA - A novel hybrid butterfly optimization algorithm with symbiosis organisms search for global optimization and image segmentation

The conventional Butterfly Optimization Algorithm (BOA) does not appropriately balance the exploration and exploitation characteristics of an algorithm to solve present-day challenging optimization problems. For the same, in this paper, a novel hybrid BOA (MPBOA, in short) is suggested, where the BOA is combined with mutualism and parasitism phases of the Symbiosis Organisms Search (SOS) algorithm to enhance the search behaviour (both global and local) of BOA. The mutualism phase is applied with the global phase of BOA, and the parasitism phase is added with the local phase of BOA to ensure a better trade-off between the global and local search of the proposed algorithm. A suit of twenty-five benchmark functions is employed to investigate its performance with several other state-of-the-art algorithms available in the literature. Also, to check its performance statistically, the Friedman rank test and t-test are carried out. The consistency of the proposed algorithm is tested with a boxplot diagram. Also, four real-world problems are solved to check the efficiency of the algorithm in solving industrial problems. Finally, the proposed MPBOA is utilized to obtain the optimal threshold in the multilevel thresholding problem of the segmentation of individual images. From the obtained results, it is found that the overall performance of the newly introduced MPBOA is satisfactory in terms of its search behaviour and convergence time to obtain global optima.

     

An enhanced beam search algorithm for the Shortest Common Supersequence Problem

The Shortest Common Supersequence Problem asks to obtain a shortest string that is a supersequence of every member of a given set of strings. It has applications, among others, in data compression and oligonucleotide microarray production. The problem is NP-hard, and the existing exact solutions are impractical for large instances. In this paper, a new beam search algorithm is proposed for the problem, which employs a probabilistic heuristic and uses the dominance property to further prune the search space. The proposed algorithm is compared with three recent algorithms proposed for the problem on both random and biological sequences, outperforming them all by quickly providing solutions of higher average quality in all the experimental cases. The Java source and binary files of the proposed IBS_SCS algorithm and our implementation of the DR algorithm and all the random and real datasets used in this paper are freely available upon request.     

基于逐维策略的布谷鸟搜索增强算法

布谷鸟搜索算法迭代运用Lévy Flights随机走动和Biased随机走动发现新个体的各维信息。当个体所有维信息生成后,算法将这些信息合成为个体并评价。在这种情况下,由于个体各维之间存在相互干扰,一些部分维进化的个体可能被放弃,从而影响算法的收敛速度以及求精能力。提出的布谷鸟搜索增强算法采用逐维评价策略接收一些部分进化的个体,可进一步增强算法的收敛速度和求精能力。在算法中,逐维评价策略作为局部搜索技术镶嵌在两个随机走动部件之后,并随机选择一些个体进行逐维更新后进行评价。实验结果说明逐维评价策略总体上能够有效且较好地改善算法的求解性能和收敛速度。     

An efficient binary chaotic symbiotic organisms search algorithm approaches for feature selection problems

The Journal of Supercomputing - Feature selection is one of the main steps in preprocessing data in machine learning, and its goal is to reduce features by removing additional and noisy features....     

Sequential quadratic programming enhanced backtracking search algorithm

In this paper, we propose a new hybrid method called SQPBSA which combines backtracking search optimization algorithm (BSA) and sequential quadratic programming (SQP). BSA, as an exploration search engine, gives a good direction to the global optimal region, while SQP is used as a local search technique to exploit the optimal solution. The experiments are carried on two suits of 28 functions proposed in the CEC-2013 competitions to verify the performance of SQPBSA. The results indicate the proposed method is effective and competitive.     

自适应精英反向学习共生生物搜索算法

针对共生生物搜索算法在求解高维复杂问题时存在过早收敛,求解精度不高及后期搜索迟滞等问题,结合自适应思想,利用不同差分扰动项和精英反向学习策略对算法进行改进,得到一种改进的共生生物搜索算法。对14个标准测试函数的仿真实验结果进行分析,相比于原算法和其他三种目前流行的算法,改进算法在收敛速度和求解精度方面均具有明显的优势,寻优能力更强。     

Discrete symbiotic organisms search algorithm for travelling salesman problem

A Discrete Symbiotic Organisms Search (DSOS) algorithm for finding a near optimal solution for the Travelling Salesman Problem (TSP) is proposed. The SOS is a metaheuristic search optimization algorithm, inspired by the symbiotic interaction strategies often adopted by organisms in the ecosystem for survival and propagation. This new optimization algorithm has been proven to be very effective and robust in solving numerical optimization and engineering design problems. In this paper, the SOS is improved and extended by using three mutation-based local search operators to reconstruct its population, improve its exploration and exploitation capability, and accelerate the convergence speed. To prove that the proposed solution approach of the DSOS is a promising technique for solving combinatorial problems like the TSPs, a set of benchmarks of symmetric TSP instances selected from the TSPLIB library are used to evaluate its performance against other heuristic algorithms. Numerical results obtained show that the proposed optimization method can achieve results close to the theoretical best known solutions within a reasonable time frame.     

Using an enhanced scatter search algorithm for a resource-constrained project scheduling problem

The resource-constrained project scheduling problem is one of the classical problems in the field of operations research. There are many criteria to efficiently determine the desired schedule of a project. In this paper, a well-known criterion namely project’s makespan is considered. Due to the complexity of the problem, it is very difficult to obtain optimum solution for this kind of problems by means of traditional methods. Therefore, an enhanced scatter search, based on a new path relinking and two prominent permutation-based and crossover operators, is devised to solve the problem. In order to validate the performance of the proposed algorithm, in terms of solution quality, the algorithm is applied to various test problems available on the literature and the reliability of it, is compared with well-reported benchmark algorithms. The computational results reveal that the proposed algorithm has appropriate results in comparison with the existing benchmark algorithms.     

基于子种群拉伸操作的精英共生生物搜索算法

针对共生生物搜索算法存在易早熟、收敛速度慢等缺陷,提出一种基于子种群拉伸操作的精英共生生物搜索算法.在“互利共生”阶段,根据适应度值将种群划分为两个子种群,设计有针对性的进化策略,使两个子种群分别负责开发和探索,有效地平衡算法的收敛速度与精度;在“偏利共生”阶段,利用最优个体的方向性引导信息,引入拉伸因子和差分扰动向量,并修正个体更新模式,从而在提高算法收敛速度的同时保证种群的多样性;模拟寄生体和宿主的生物关系,提出精英“寄生”机制,进一步平衡算法在整个迭代过程中的探索与开发能力.对与标准共生生物算法、改进后的共生生物搜索算法以及其他4个群智能进化算法在17个函数上的测试结果进行比较分析,结果表明所提出的算法精度更佳,收敛速度优势明显.     

面向路径规划问题的虚拟多任务共生生物搜索算法

针对现有共生生物搜索(SOS)算法在求解路径规划等离散型优化问题时存在性能较差、收敛速度慢等问题,提出虚拟多任务共生生物搜索(VMTSOS)算法。首先根据双向映射解码策略,实现个体连续空间位置和离散城市序列转换;然后引入多任务优化思想构建虚拟多任务环境,设计多种群同时优化同一任务,并通过停滞阈值控制种群间信息迁移频率,当主种群达到停滞阈值时,将辅助种群中部分优秀个体替换为主种群劣质个体;最后对VMTSOS算法时间和空间复杂度进行分析。仿真实验表明,VMTSOS算法在求解多数TSP时均能快速收敛至各测试实例目前的最优解,而在求解冷链物流配送问题时,具有多种群辅助机制的VMTSOS算法能较大程度地降低最优总成本。     

An advertisement-based peer-to-peer search algorithm

Most of the existing search algorithms for unstructured peer-to-peer (P2P) systems share one common approach: the requesting node sends out a keyword search query and the query message is repeatedly routed and forwarded to other peers in the overlay network. Due to multiple hops involved in query forwarding, the search may result in a long delay before it is answered. Furthermore, some incapable nodes may be overloaded when the query traffic becomes intensive or bursty.     

一种改进的快速搜索算法

提出了一种基于预测的自适应六边形搜索方法,并将此算法与其他常用的快速运动估计算法进行实验比较。实验结果表明:该算法有效地降低了搜索点数,搜索精度比较接近于FS算法,在一定程度上提高了搜索的效率。     

Symbiotic organisms search algorithm for dynamic economic dispatch with valve-point effects

Abstract

In this study, symbiotic organisms search (SOS) algorithm is proposed to solve the dynamic economic dispatch with valve-point effects problem, which is one of the most important problems of the modern power system. Some practical constraints like valve-point effects, ramp rate limits and prohibited operating zones have been considered as solutions. Proposed algorithm was tested on five different test cases in 5 units, 10 units and 13 units systems. The obtained results have been compared with other well-known metaheuristic methods reported before. Results show that proposed algorithm has a good convergence and produces better results than other methods.     

增强寻优能力的自适应人工蜂群算法*

针对人工蜂群算法在求解函数优化问题中存在收敛精度不高、收敛速度较慢的问题,提出了一种改进的增强寻优能力的自适应人工蜂群算法。该算法利用逻辑自映射函数产生混沌序列对雇佣蜂搜索行为进行混沌优化,并引入萤火虫算法中的自适应步长策略动态调整观察蜂的搜索行为,从而提升了算法的局部搜索能力。基于标准测试函数的仿真结果表明,改进后的人工蜂群算法在寻优精度和收敛速度上均有明显提高。     

An enhanced simulation-based design method coupled with meta-heuristic search algorithm for accurate reliability-based design optimization

The enhanced weighted simulation-based design method in conjunction with particle swarm optimization (PSO) is developed as a pseudo double-loop algorithm for accurate reliability-based design optimization (RBDO). According to this hybrid method, generated samples of weighed simulation method (WSM) are considered as initial population of the PSO. The proposed population is then employed to evaluate the safety level of each PSO swarm (design candidates) during movement. Using this strategy, there is no required to conduct new sampling for reliability assessment of design candidates (PSO swarms). Employing PSO as the search engine of RBDO and WSM as the reliability analyzer provide more accurate results with few samples and also increase the application range of traditional WSM. Besides, a shift strategy is also introduced to increase the capability of the WSM to investigate general RBDO problems including both deterministic and random design variables. Several examples are investigated to demonstrate the accuracy and robustness of the method. Results demonstrate the computational efficiency and superiority of the proposed method for practical engineering problems with highly nonlinear and implicit probabilistic constrains.     

A hybrid OBL-based firefly algorithm with symbiotic organisms search algorithm for solving continuous optimization problems

The metaheuristic optimization algorithms are relatively new optimization algorithms introduced to solve optimization problems in recent years. For example, the firefly algorithm (FA) is one of the metaheuristic algorithms inspired by the fireflies' flashing behavior. However, its weakness in terms of exploration and early convergence has been pointed out. In this paper, two approaches were proposed to improve the FA. In the first proposed approach, a new improved opposition-based learning FA (IOFA) method was presented to accelerate the convergence and improve the FA's exploration capability. In the second proposed approach, a symbiotic organisms search (SOS) algorithm improved the exploration and exploitation of the first approach; two new parameters set these two goals, and the second approach was named IOFASOS. The purpose of the second method is that in the process of the SOS algorithm, the whole population is effective in the IOFA method to find solutions in the early stages of implementation, and with each iteration, fewer solutions are affected in the population. The experiments on 24 standard benchmark functions were conducted, and the first proposed approach showed a better performance in the small and medium dimensions and exhibited a relatively moderate performance in the higher dimensions. In contrast, the second proposed approach was better in increasing dimensions. In general, the empirical results showed that the two new approaches outperform other algorithms in most mathematical benchmarking functions. Thus, The IOFASOS model has more efficient solutions.

     

A novel symbiotic organisms search algorithm for congestion management in deregulated environment

Abstract

In today’s competitive electricity market, managing transmission congestion in deregulated power system has created challenges for independent system operators to operate the transmission lines reliably within the limits. This paper proposes a new meta-heuristic algorithm, called as symbiotic organisms search (SOS) algorithm, for congestion management (CM) problem in pool based electricity market by real power rescheduling of generators. Inspired by interactions among organisms in ecosystem, SOS algorithm is a recent population based algorithm which does not require any algorithm specific control parameters unlike other algorithms. Various security constraints such as load bus voltage and line loading are taken into account while dealing with the CM problem. In this paper, the proposed SOS algorithm is applied on modified IEEE 30- and 57-bus test power system for the solution of CM problem. The results, thus, obtained are compared to those reported in the recent state-of-the-art literature. The efficacy of the proposed SOS algorithm for obtaining the higher quality solution is also established.     

采用改进型SOS算法的光伏组件模型参数辨识

针对当前大部分光伏（photovoltaic,PV）模型参数辨识算法均存在准确性低和可靠性差等问题,提出了一种采用改进型共生生物搜索算法（symbiotic organisms search,SOS）的光伏组件模型参数辨识方法。首先,为提高标准SOS算法的寻优性能,提出了新的改进型SOS算法,记作ImSOS算法。该算法在标准SOS算法的生物种群初始化阶段采用了准反射学习机制;在互利共生搜索阶段采用了改进受益因子策略;在偏利共生搜索阶段采用了收缩随机数产生因子区间策略。其次,给出了采用ImSOS算法求解基于实验测量电流—电压（I-V）数据的光伏组件模型参数辨识问题的具体步骤及实现流程。最后,利用实际Sharp ND-R250A5光伏组件进行实验,通过与标准SOS算法以及其他七种新颖智能优化算法进行对比验证,结果表明了ImSOS算法在光伏组件模型参数辨识的有效性和优越性。可见ImSOS算法为准确可靠地辨识光伏组件模型参数提供了一种新的有效方法。