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1.
Due to the slow convergence of Gaussian particle swarm algorithm (GPSO) during parameters selection of support vector machine (SVM), this paper proposes a novel PSO with hybrid mutation strategy. Since random number generated from Cauchy distribution has better convergence characteristic than ones from Gaussian distribution during mutation strategy. Cauchy mutation is applied to amend the decision-making variable of Gaussian PSO. The adaptive mutation based on the fitness function value and the iterative variable is also applied to inertia weight of PSO. The results of application in parameter selection of support vector machine show the proposed GPSO with Cauchy mutation strategy is feasible and effective, and the comparison between the method proposed in this paper and other ones is also given, which proves this method is better than Gaussian PSO.  相似文献   

2.
This paper presents a novel hybrid forecasting model based on support vector machine and particle swarm optimization with Cauchy mutation objective and decision-making variables. On the basis of the slow convergence of particle swarm algorithm (PSO) during parameters selection of support vector machine (SVM), the adaptive mutation operator based on the fitness function value and the iterative variable is also applied to inertia weight. Then, a hybrid PSO with adaptive and Cauchy mutation operator (ACPSO) is proposed. The results of application in regression estimation show the proposed hybrid model (ACPSO–SVM) is feasible and effective, and the comparison between the method proposed in this paper and other ones is also given, which proves this method is better than other methods.  相似文献   

3.
论文针对标准量子粒子群算法易陷入局部极值的问题,提出一种改进的量子粒子优化最小二乘支持向量机的方法。利用高斯变异数的局部开发能力以及柯西变异数的全局搜索能力,在量子粒子群优化算法中,引入高斯-柯西变异算子,帮助算法跳出局部极值。并利用该优化模型进行光伏发电量预测实验,对优化的最小二乘支持向量机模型的预测结果与其他模型预测结果进行比较,结果表明:基于高斯-柯西变异算子的量子粒子群优化的最小二乘支持向量机对光伏发电量的预测具备较好的收敛速度和跳出局部收敛困境的能力。  相似文献   

4.
This paper presents a new version of fuzzy support vector classifier machine to diagnose the nonlinear fuzzy fault system with multi-dimensional input variables. Since there exist problems of Gaussian noises and uncertain data in complex fuzzy fault system modeling, the input and output variables are described as fuzzy numbers. Then by integrating fuzzy theory, Gaussian loss function and v-support vector classifier machine, the fuzzy Gaussian v-support vector regression machine (Fg-SVCM) is proposed. To seek the optimal parameters of Fg-SVCM, the modified genetic algorithm (GA) is also applied to optimize parameters of Fg-SVCM. A diagnosing method based on Fg-SVCM and GA is put forward. The results of application in fault diagnosis of car assembly line show the hybrid diagnosis model based on Fg-SVCM and PSO is feasible and effective, and the comparison between the method proposed in this paper and other ones is also given, which proves this method is better than other v-SVCMs.  相似文献   

5.
进化策略是一类策略参数自适应进化算法。文章提出了一种改进进化策略(MES),MES采用基于个体排序的随机自适应Gaussian-Cauchy混合变异策略,将Gaussian和Cauchy变异算子结合起来以达到全局探索和局部搜索之间的动态平衡。此外,MES还使用重组算子以进一步提高算法的性能。将该算法用于多层前向神经网络训练,数值仿真结果显示了该算法的有效性。  相似文献   

6.
提出一种新的求解函数优化的快速演化算法;新算法的特征是引入一种基于高斯变异和Cauchy变异的混合自适应变异算子,并作为算法的唯一遗传算子;提出多父体变异的群体爬山搜索策略;采用随机排序选择策略,克服了经典算法易于陷入局部最优解的常见弊病;新算法具有保持群体的多样性、全概率收敛、淘汰压力小、子空间搜索、快速收敛、评价次数少等特性;通过7个标准测试函数测试结果表明,新算法在所有的测试函数中体现出很好的性能,具有稳定、高效和快速等特点.  相似文献   

7.
Model selection plays a key role in the application of support vector machine (SVM). In this paper, a method of model selection based on the small-world strategy is proposed for least squares support vector regression (LS-SVR). In this method, the model selection is treated as a single-objective global optimization problem in which generalization performance measure performs as fitness function. To get better optimization performance, the main idea of depending more heavily on dense local connections in small-world phenomenon is considered, and a new small-world optimization algorithm based on tabu search, called the tabu-based small-world optimization (TSWO), is proposed by employing tabu search to construct local search operator. Therefore, the hyper-parameters with best generalization performance can be chosen as the global optimum based on the powerful search ability of TSWO. Experiments on six complex multimodal functions are conducted, demonstrating that TSWO performs better in avoiding premature of the population in comparison with the genetic algorithm (GA) and particle swarm optimization (PSO). Moreover, the effectiveness of leave-one-out bound of LS-SVM on regression problems is tested on noisy sinc function and benchmark data sets, and the numerical results show that the model selection using TSWO can almost obtain smaller generalization errors than using GA and PSO with three generalization performance measures adopted.  相似文献   

8.
为了更好地满足云计算中用户的服务质量(Quality of Service, QoS)需求,合理利用云数据中心的资源,以任务的执行时间和虚拟机的负载均衡作为优化的目标对象,提出了一种基于烟花算法(Fireworks Algorithm, FWA)的多目标优化调度模型。烟花算法是一种启发式算法,利用爆炸算子、高斯变异和选择策略能较快地寻找到全局最优解。通过在Cloudsim上与粒子群优化算法(PSO)和遗传算法(GA)进行有效性和执行时间上的对比,结果表明烟花算法在不同实验次数下可持续得到最优适应度值,而且在种群规模不断扩大时,烟花算法的执行时间没有陡然增加,明显优于PSO算法和GA算法。  相似文献   

9.
Ensemble strategies with adaptive evolutionary programming   总被引:1,自引:0,他引:1  
Mutation operators such as Gaussian, Lévy and Cauchy have been used with evolutionary programming (EP). According to the no free lunch theorem, it is impossible for EP with a single mutation operator to outperform always. For example, Classical EP (CEP) with Gaussian mutation is better at searching in a local neighborhood while the Fast EP (FEP) with the Cauchy mutation performs better over a larger neighborhood. Motivated by these observations, we propose an ensemble approach where each mutation operator has its associated population and every population benefits from every function call. This approach enables us to benefit from different mutation operators with different parameter values whenever they are effective during different stages of the search process. In addition, the recently proposed Adaptive EP (AEP) using Gaussian (ACEP) and Cauchy (AFEP) mutations is also evaluated. In the AEP, the strategy parameter values are adapted based on the search performance in the previous few generations. The performance of ensemble is compared with a mixed mutation strategy, which integrates several mutation operators into a single algorithm as well as against the AEP with a single mutation operator. Improved performance of the ensemble over the single mutation-based algorithms and mixed mutation algorithm is verified using statistical tests.  相似文献   

10.
马驰  阮秋琦 《微机发展》2007,17(12):20-23
支持向量机(SVM)的学习性能和泛化能力主要取决于参数选择,然而传统的优化算法难以解决此问题。文中通过支持向量的个数建立优化目标函数,采用微粒群优化(PSO)算法对其优化,寻找最优参数。PSO是一种新兴的基于群体智慧的进化算法。实验表明,微粒群优化算法是支持向量机参数选择的有效方法。  相似文献   

11.
This paper presents a new load forecasting model based on hybrid particle swarm optimization with Gaussian and adaptive mutation (HAGPSO) and wavelet v-support vector machine (Wv-SVM). Firstly, it is proved that mother wavelet function can build a set of complete base through horizontal floating and form the wavelet kernel function. And then, Wv-SVM with wavelet kernel function is proposed in this paper. Secondly, aiming to the disadvantage of standard PSO, HAGPSO is proposed to seek the optimal parameter of Wv-SVM. Finally, the load forecasting model based on HAGPSO and Wv-SVM is proposed in this paper. The results of application in load forecasts show the proposed model is effective and feasible.  相似文献   

12.
一种自适应柯西变异的反向学习粒子群优化算法   总被引:1,自引:0,他引:1  
针对传统粒子群优化算法易出现早熟的问题,提出了一种自适应变异的反向学习粒子群优化算法。该算法在一般性反向学习方法的基础上,提出了自适应柯西变异策略(ACM)。采用一般性反向学习策略生成反向解,可扩大搜索空间,增强算法的全局勘探能力。为避免粒子陷入局部最优解而导致搜索停滞现象的发生,采用ACM策略对当前最优粒子进行扰动,自适应地获取变异点,在有效提高算法局部开采能力的同时,使算法能更加平稳快速地收敛到全局最优解。为进一步平衡算法的全局搜索与局部探测能力,采用非线性的自适应惯性权值。将算法在14个测试函数上与多种基于反向学习策略的PSO算法进行对比,实验结果表明提出的算法在解的精度以及收敛速度上得到了大幅度的提高。  相似文献   

13.
李俊  汪冲  李波  方国康 《计算机应用》2016,36(3):681-686
针对粒子群优化(PSO)算法容易早熟收敛、在进化后期收敛精度低的缺点,提出了一种基于多策略协同作用的粒子群优化(MSPSO)算法。首先,设定一个概率阈值为0.3,在粒子迭代过程中,如果随机生成的概率值小于阈值,则采用对当前种群中的最优个体进行反向学习并生成其反向解,以提高算法的收敛速度和收敛精度;否则,算法执行对粒子的位置进行高斯变异策略,以增强种群的多样性;其次,提出一种将柯西分布的比例参数进行线性递减的柯西变异策略,能够产生更好的解引导粒子向最优解空间运动;最后,在8个标准测试函数上进行仿真测试,MSPSO算法在Rosenbrock、Schwefel's P2.22、Rotated Ackley、Quadric Noise、Ackley函数上收敛的平均值分别为1.68E+01、2.36E-283、8.88E-16、2.78E-05、8.88E-16,在Sphere、Griewank和Rastrigin函数上收敛达到最优解0,优于高斯扰动粒子群优化(GDPSO)算法、基于柯西变异的反向学习粒子群优化(GOPSO)算法。结果表明,所提出的算法收敛精度高,能避免粒子陷入局部最优。  相似文献   

14.
This paper presents a new version of fuzzy support vector classifier machine to diagnose the nonlinear fuzzy fault system with multi-dimensional input variables. Since there exist problems of finite samples and uncertain data in complex fuzzy fault system modeling, the input and output variables are described as fuzzy numbers. Then by integrating the fuzzy theory and v-support vector classifier machine, the triangular fuzzy v-support vector regression machine (TF v-SVCM) is proposed. To seek the optimal parameters of TF v-SVCM, particle swarm optimization (PSO) is also applied to optimize parameters of TF v-SVCM. A diagnosing method based on TF v-SVCM and PSO are put forward. The results of the application in fault system diagnosis confirm the feasibility and the validity of the diagnosing method. The results of application in fault diagnosis of car assembly line show the hybrid diagnosis model based on TF v-SVCM and PSO is feasible and effective, and the comparison between the method proposed in this paper and other ones is also given, which proves this method is better than standard v-SVCM.  相似文献   

15.
针对帝王蝶优化算法(MBO)全局搜索能力较弱、在迁移过程中容易出现种群多样性减少等问题,文中提出基于柯西变异的差分自适应MBO及其特征选择算法.首先,使用差分进化算法中的变异操作替换MBO的迁移算子,提升全局搜索能力.然后,将自适应调整策略融入MBO的调整算子,改变单一的调整方式.最后,对每次更新的种群进行柯西变异,增加种群多样性.为了验证改进帝王蝶优化算法及其特征选择方法的性能,通过基准函数和UCI数据集两部分实验对其进行测试,结果表明文中算法性能较优.  相似文献   

16.
改进的粒子群优化算法的研究和分析   总被引:2,自引:0,他引:2       下载免费PDF全文
粒子群优化算法是一种新的随机全局优化进化算法。为了有效地控制其全局搜索和局部搜索,使之获得较好的平衡,论文在深入分析和研究标准粒子群优化算法的基础上,提出了一种基于进化代数阈值和粒子间最大聚集距离高斯变异的粒子群优化算法。该算法在运行过程中通过粒子聚集程度的量化判定,对当前的最优粒子施加高斯变异,从而增强粒子群优化算法跳出局部最优解的能力。测试函数仿真结果表明了该算法的可行性和有效性。  相似文献   

17.
This paper presents a hybrid filter-wrapper feature subset selection algorithm based on particle swarm optimization (PSO) for support vector machine (SVM) classification. The filter model is based on the mutual information and is a composite measure of feature relevance and redundancy with respect to the feature subset selected. The wrapper model is a modified discrete PSO algorithm. This hybrid algorithm, called maximum relevance minimum redundancy PSO (mr2PSO), is novel in the sense that it uses the mutual information available from the filter model to weigh the bit selection probabilities in the discrete PSO. Hence, mr2PSO uniquely brings together the efficiency of filters and the greater accuracy of wrappers. The proposed algorithm is tested over several well-known benchmarking datasets. The performance of the proposed algorithm is also compared with a recent hybrid filter-wrapper algorithm based on a genetic algorithm and a wrapper algorithm based on PSO. The results show that the mr2PSO algorithm is competitive in terms of both classification accuracy and computational performance.  相似文献   

18.
给出了一种乳腺X线照片微钙化点的特征选择方法,该方法运用基于加权变异算子的免疫算法进行特征优选。加权变异算子能够动态调整抗体各部位的变异率,在高亲和力抗体的邻近小范围搜索,在低亲和力抗体的周围跳跃式搜索;为了与支持向量机的分类准则保持一致性,该免疫算法在特征空间中通过核函数计算亲和力。实验使用该方法对微钙化点的20种常用特征进行选择,其结果与经验特征集基本相符但更精简,提高了计算效率,是一种可行的特征选择方法。  相似文献   

19.
高斯过程分类是近年机器学习领域引起广泛关注的一类有监督的学习算法。该算法在高斯过程的先验假设下,以后验概率最大化的为目标,获得对新样本的预测值及属于该值的概率。针对图像数据的特性,提出一种将高斯过程应用于图像分类的方法,同时在此基础上给出对图片进行排序的一种方案。在公开的图像数据集上进行了实验,并与支持向量机分类器进行对比,证实了其有效性,为改进图像分类技术提供一条可供参考的途径。  相似文献   

20.
This paper introduces a novel meta-heuristic, the chaos-based improved immune algorithm (CBIIA), for solving resource-constrained project scheduling problems (RCPSP). In RCPSP the activities of a project have to be scheduled with the objective of minimizing total makespan subject to both temporal and resource constraints. The proposed CBIIA is based on the traits of an artificial immune system, chaotic generator and parallel mutation. CBIIA is different from the traditional immune algorithm in its initialization and hypermutation mechanism. Initialization in CBIIA is done by using chaotic generator (Logistic, Tent, and Sinusoidal) instead of conventional random number generator (RNG). The hypermutation is performed by parallel mutation (PM) operator rather than point mutation. Parallel mutation comprises two mutation strategies viz. Gaussian and Cauchy. Gaussian strategy is utilized for small step mutation and Cauchy strategy is for large step mutation. In order to demonstrate the efficacy of the proposed algorithm, Patterson’s test suites are worked out. This study aims at developing an alternative and more efficient optimization methodology and opening the application of variants of artificial immune system for solving the RCPSP.  相似文献   

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