An immune memory clonal algorithm for numerical and combinatorial optimization

Inspired by the clonal selection theory together with the immune network model, we present a new artificial immune algorithm named the immune memory clonal algorithm (IMCA). The clonal operator, inspired by the immune system, is discussed first. The IMCA includes two versions based on different immune memory mechanisms; they are the adaptive immune memory clonal algorithm (AIMCA) and the immune memory clonal strategy (IMCS). In the AIMCA, the mutation rate and memory unit size of each antibody is adjusted dynamically. The IMCS realizes the evolution of both the antibody population and the memory unit at the same time. By using the clonal selection operator, global searching is effectively combined with local searching. According to the antibody-antibody (Ab-Ab) affinity and the antibody-antigen (Ab-Ag) affinity, The IMCA can adaptively allocate the scale of the memory units and the antibody population. In the experiments, 18 multimodal functions ranging in dimensionality from two, to one thousand and combinatorial optimization problems such as the traveling salesman and knapsack problems (KPs) are used to validate the performance of the IMCA. The computational cost per iteration is presented. Experimental results show that the IMCA has a high convergence speed and a strong ability in enhancing the diversity of the population and avoiding premature convergence to some degree. Theoretical roof is provided that the IMCA is convergent with probability 1.     

一种免疫记忆动态克隆策略算法

基于对克隆选择及免疫记忆动态过程的模拟,本文提出了一种人工智能算法,免疫记忆动态克隆策略算法,该算法模拟免疫系统的自我调节、记忆学习、自适应等机制,实现全局优化计算与局部优化计算机制的有机的结合,通过抗体与抗原的亲合度和抗体间亲合度的计算,促进和抑制抗体的产生,自适应地调节抗体群和记忆单元的克隆规模.理论分析证明该算法以概率1收敛,对多峰函数优化及货郎担问题的仿真试验表明,算法有效,而且具有全局搜索能力强,种群多样性好及收敛速度快等特点.     

空间自适应免疫克隆选择优化算法

针对免疫克隆选择优化算法晚期收敛速度慢的不足,通过引入搜索空间自适应缩放的思想,提出一种新的空间自适应免疫克隆选择优化算法(SAIS)。算法利用不完全演化搜索优化解的分布特性,以精英个体为中心收缩搜索空间,并采用空间扩张机制帮助算法跳出局部最优。通过对高维基准测试函数实验表明,SAIS能显著提高收敛速度和优化解的质量。     

机械手优化的病毒进化型免疫克隆算法

针对平动式轻型装卸机的机械手结构优化设计问题,在免疫克隆算法基础上,通过引入病毒协同进化机制,提出了一种新的病毒进化型免疫克隆优化算法。新算法主要对免疫变异后种群进行病毒感染操作,从而改善宿主种群的多样性,增强免疫克隆算法的局部搜索能力。实验结果表明,与其他优化算法相比,病毒进化型免疫克隆算法的搜索能力更强,收敛速度更快,明显改善了机械手结构的优化设计能力。     

Quantum immune clonal coevolutionary algorithm for dynamic multiobjective optimization

The existing algorithms to solve dynamic multiobjective optimization (DMO) problems generally have difficulties in non-uniformity, local optimality and non-convergence. Based on artificial immune system, quantum evolutionary computing and the strategy of co-evolution, a quantum immune clonal coevolutionary algorithm (QICCA) is proposed to solve DMO problems. The algorithm adopts entire cloning and evolves the theory of quantum to design a quantum updating operation, which improves the searching ability of the algorithm. Moreover, coevolutionary strategy is incorporated in global operation and coevolutionary competitive operation and coevolutionary cooperative operation are designed to improve the uniformity, the diversity and the convergence performance of the solutions. The results on test problems and performance metrics compared with ICADMO and DBM suggest that QICCA has obvious effectiveness and advantages which shows great capability of evolving convergent, diverse and uniformly distributed Pareto fronts.     

一种基于记忆克隆选择的多目标免疫算法

借鉴生物免疫原理中克隆选择机理,设计了一种基于记忆克隆选择的多目标免疫算法。该算法构建了一种亲和度的快速计算方法,并在抗体种群全局搜索Pareto解的同时,也在记忆单元进行局部搜索,有效地提高了搜索效率和收敛性。选取了六种典型的多目标优化函数进行算法仿真测试研究,并与经典的多目标进化算法NSGA-II进行了比较。仿真研究结果证明了新算法在保证种群分布度的同时,拥有比NSGA-II更好的收敛性和速度。     

一种改进的克隆函数优化算法*

为了提高免疫克隆算法的寻优能力,借鉴生物免疫系统的Baldwin效应及生物进化的周期性,提出了一种Baldwin效应的正向和反向学习机制,克服纯粹随机进化;利用生物进化的周期性,设计了周期变异算子,提高算法的收敛速度。在函数测试问题上的仿真实验表明,该算法求解精度较高、寻优能力较强。     

免疫文化基因算法求解多模态函数优化问题

为了尽可能找到多模函数优化问题的全部最优解,提出了一种免疫文化基因算法。采用危险信号自适应引导免疫克隆、变异和选择过程,并采用Baldwin学习机制作为局部搜索策略,增强了算法搜索最优解的能力。实验结果表明,本算法求解精度较高。     

An improved teaching-learning-based optimization algorithm for numerical and engineering optimization problems

The teaching-learning-based optimization (TLBO) algorithm, one of the recently proposed population-based algorithms, simulates the teaching-learning process in the classroom. This study proposes an improved TLBO (ITLBO), in which a feedback phase, mutation crossover operation of differential evolution (DE) algorithms, and chaotic perturbation mechanism are incorporated to significantly improve the performance of the algorithm. The feedback phase is used to enhance the learning style of the students and to promote the exploration capacity of the TLBO. The mutation crossover operation of DE is introduced to increase population diversity and to prevent premature convergence. The chaotic perturbation mechanism is used to ensure that the algorithm can escape the local optimal. Simulation results based on ten unconstrained benchmark problems and five constrained engineering design problems show that the ITLBO algorithm is better than, or at least comparable to, other state-of-the-art algorithms.     

An adaptive single-point algorithm for global numerical optimization

This paper describes a novel algorithm for numerical optimization, called Simple Adaptive Climbing (SAC). SAC is a simple efficient single-point approach that does not require a careful fine-tunning of its two parameters. SAC algorithm shares many similarities with local optimization heuristics, such as random walk, gradient descent, and hill-climbing. SAC has a restarting mechanism, and a powerful adaptive mutation process that resembles the one used in Differential Evolution. The algorithms SAC is capable of performing global unconstrained optimization efficiently in high dimensional test functions. This paper shows results on 15 well-known unconstrained problems. Test results confirm that SAC is competitive against state-of-the-art approaches such as micro-Particle Swarm Optimization, CMA-ES or Simple Adaptive Differential Evolution.     

An improved multi-agent genetic algorithm for numerical optimization

Multi-agent genetic algorithm (MAGA) is a good algorithm for global numerical optimization. It exploited the known characteristics of some benchmark functions to achieve outstanding results. But for some novel composition functions, the performance of the MAGA significantly deteriorates when the relative positions of the variables at the global optimal point are shifted with respect to the search ranges. To this question, an improved multi-agent genetic algorithm for numerical optimization (IMAGA) is proposed. IMAGA make use of the agent evolutionary framework, and constructs heuristic search and a hybrid crossover strategy to complete the competition and cooperation of agents, a convex mutation operator and some local search to achieve the self-learning characteristic. Using the theorem of Markov chain, the improved multi-agent genetic algorithm is proved to be convergent. Experiments are conducted on some benchmark functions and composition functions. The results demonstrate good performance of the IMAGA in solving complicated composition functions compared with some existing algorithms.     

An organizational evolutionary algorithm for numerical optimization.

Taking inspiration from the interacting process among organizations in human societies, this correspondence designs a kind of structured population and corresponding evolutionary operators to form a novel algorithm, Organizational Evolutionary Algorithm (OEA), for solving both unconstrained and constrained optimization problems. In OEA, a population consists of organizations, and an organization consists of individuals. All evolutionary operators are designed to simulate the interaction among organizations. In experiments, 15 unconstrained functions, 13 constrained functions, and 4 engineering design problems are used to validate the performance of OEA, and thorough comparisons are made between the OEA and the existing approaches. The results show that the OEA obtains good performances in both the solution quality and the computational cost. Moreover, for the constrained problems, the good performances are obtained by only incorporating two simple constraints handling techniques into the OEA. Furthermore, systematic analyses have been made on all parameters of the OEA. The results show that the OEA is quite robust and easy to use.     

Co-evolution-based immune clonal algorithm for clustering

Clustering is an important tool in data mining process. Fuzzy \(c\)-means is one of the most classic methods. But it has been criticized that it is sensitive to the initial cluster centers and is easy to fall into a local optimum. Not depending on the selection of the initial population, evolutionary algorithm is used to solve the problems existed in original fuzzy \(c\)-means algorithm. However, evolutionary algorithm emphasizes the competition in the population. But in the real world, the evolution of biological population is not only the result of internal competition, but also the result of mutual competition and cooperation among different populations. Co-evolutionary algorithm is an emerging branch of evolutionary algorithm. It focuses on the internal competition, while on the cooperation among populations. This is more close to the process of natural biological evolution and co-evolutionary algorithm is a more excellent bionic algorithm. An immune clustering algorithm based on co-evolution is proposed in this paper. First, the clonal selection method is used to achieve the competition within population to reconstruct each population. The internal evolution of each population is completed during this process. Second, co-evolution operation is conducted to realize the information exchange among populations. Finally, the iteration results are compared with the global best individuals, with a strategy called elitist preservation, to find out the individual with a highest fitness value, that is, the result of clustering. Compared with four state-of-art algorithms, the experimental results indicate that the proposed algorithm outperforms other algorithms on the test data in the highest accuracy and average accuracy.     

An improved ant colony optimization algorithm for solving a complex combinatorial optimization problem

This paper presents an improved ant colony optimization algorithm (IACO) for solving mobile agent routing problem. The ants cooperate using an indirect form of communication mediated by pheromone trails of scent and find the best solution to their tasks guided by both information (exploitation) which has been acquired and search (exploration) of the new route. Therefore the premature convergence probability of the system is lower. The IACO can solve successfully the mobile agent routing problem, and this method has some excellent properties of robustness, self-adaptation, parallelism, and positive feedback process owing to introducing the genetic operator into this algorithm and modifying the global updating rules. The experimental results have demonstrated that IACO has much higher convergence speed than that of genetic algorithm (GA), simulated annealing (SA), and basic ant colony algorithm, and can jump over the region of the local minimum, and escape from the trap of a local minimum successfully and achieve the best solutions. Therefore the quality of the solution is improved, and the whole system robustness is enhanced. The algorithm has been successfully integrated into our simulated humanoid robot system which won the fourth place of RoboCup2008 World Competition. The results of the proposed algorithm are found to be satisfactory.     

An approximation algorithm for interval data minmax regret combinatorial optimization problems

The general problem of minimizing the maximal regret in combinatorial optimization problems with interval data is considered. In many cases, the minmax regret versions of the classical, polynomially solvable, combinatorial optimization problems become NP-hard and no approximation algorithms for them have been known. Our main result is a polynomial time approximation algorithm with a performance ratio of 2 for this class of problems.     

基于改进量子免疫克隆多目标优化算法的火力分配问题

针对传统火力分配中存在武器资源浪费的情况,以对敌目标与网络攻击收益最大、己方武器消耗最小为目标,建立一种考虑毁伤概率约束条件的多目标火力分配模型。对标准量子免疫克隆多目标优化算法进行优化,引入了混沌机制,修复不可行解,并对搜索策略和多样性保持策略进行改进,设计了一种改进的量子免疫克隆多目标优化算法。通过实验仿真,验证了模型的正确性与算法的优越性。相比于传统量子免疫克隆算法,改进算法的性能平均提高了23%。     

免疫入侵检测多目标优化克隆选择算法研究

免疫入侵检测理论中克隆选择是检测器进化的关键。传统克隆选择算法通过比较样本间的亲和力累加值筛选样本,该方法具有较低的时间复杂度,但也造成了检测器的高重叠,影响迭代效率。将检测器个体的筛选与进化转化为pareto最优解的求解过程,提出了多目标优化理论的检测器克隆选择算法。实验表明,检测器基数不变的情况下,该算法明显提升了每代种群在进化过程中的检测范围,精简了记忆检测器的数量,提高了检测阶段系统的检测率。     

一种用于求解多目标组合优化的混合遗传算法

为高效求解多目标组合优化问题 ,提出一种进化计算与局部搜索结合的多目标算法。此算法基于个体排序数和密度值进行适应度赋值 ,采用非劣解并行局部搜索策略 ,在解的适应度赋值和局部搜索过程中使用 Pa-reto支配的概念。实验结果表明 ,新算法不仅提高了优化搜索的效率 ,且能够找到更多的近似 Pareto最优解。     

协同进化数值优化算法

为了提高进化算法的全局收敛性,提出了一种多种群同时进化的算法。根据生物学基因的多样性理论,新算法保持单个种群的相对纯洁性与整个群体繁殖方式的丰富性,不同的种群采用不同的算子,并在不同的生境繁衍后代,目的是保持种群基因的多样性。当算法陷入局部最优解领域时,可用逆向优化寻找对偶个体,使算法走出局部最优解空间。实验结果表明,在与多组优化数据的比较中,新算法在所有单项与综合项目上全部名列第一。     

An efficient and robust artificial bee colony algorithm for numerical optimization

Artificial bee colony (ABC) algorithm has already shown more effective than other population-based algorithms. However, ABC is good at exploration but poor at exploitation, which results in an issue on convergence performance in some cases. To improve the convergence performance of ABC, an efficient and robust artificial bee colony (ERABC) algorithm is proposed. In ERABC, a combinatorial solution search equation is introduced to accelerate the search process. And in order to avoid being trapped in local minima, chaotic search technique is employed on scout bee phase. Meanwhile, to reach a kind of sustainable evolutionary ability, reverse selection based on roulette wheel is applied to keep the population diversity. In addition, to enhance the global convergence, chaotic initialization is used to produce initial population. Finally, experimental results tested on 23 benchmark functions show that ERABC has a very good performance when compared with two ABC-based algorithms.