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1.
针对基于遗传算法的工作挖掘中容易淘汰掉适应度低的个体,从而丢失存在于低劣个体中的优良基因片导致得到的解不理想的情况,提出一种带分级思想的遗传算法对工作流进行挖掘。该算法采用因果矩阵作为工作流模型的编码。在创建初始种群阶段引入启发式规则,并根据个体的适应度值对种群实施分级策略,提高解的质量。仿真实验表明该方法与基于遗传算法的工作流挖掘方法相比更能产出较高质量的解。  相似文献   

2.
两段式遗传算法求解CTSP   总被引:1,自引:0,他引:1  
柴世红 《大众科技》2008,19(4):17-19
旅行商问题(TSP)是一类典型的NP完全问题,遗传算法(GA)是求解这类问题的常用方法之一。针对中国旅行商问题(CTSP),设计了两阶段遗传算法的改进策略。第一阶段在SGA基础上采取控制参数优化和保优操作,求得若干个较优解;第二阶段采用变异操作,在第一阶段较优解组成的种群基础上寻找最优解。用该策略迅速找到了CTSP最优解,该路径长度为15378km,比目前已知CTSP解更优。对遗传算法迅速求解TSP最优解提供了可行解决方案。  相似文献   

3.
关联规则挖掘是数据挖掘中一个很重要的研究课题。提出了一种基于自适应策略的动态模拟退火遗传挖掘算法。实验结果证明它能弥补基于传统遗传算法的挖掘方法的缺点。  相似文献   

4.
信息爆炸时代如何快速处理数据已成为时代的新课题.为了解决单次挖掘使用PSO算法会出现局部最优解这个矛盾,笔者提出将PSO与遗传算法互补的算法PSO遗传算法.本文通过PSO算法原理介绍,分析了遗传算法的步骤,简述了数据挖掘的概念和过程,最后提出PSO遗传算法的实施策略,并给出流程和分布实施.这种算法能有效处理海量数据进行数据挖掘,并快速收敛到解,最后输出目标数据.  相似文献   

5.
针对传统遗传算法在巡回商旅问题优化计算中存在的弊端——收敛速度慢,迭代次数多。在传统遗传算法基础上,设计出一种加入人工选择和定向突变的优化改进算法。该优化算法通过人工方法保存具有有利变异个体和淘汰具有不利变异个体,有利变异个体进行杂交和变异,从而提高遗传算法的收敛速度,减少遗传算法的迭代次数。同时针对遗传算法易陷入局部最优解的情况,在优化算法中引入自适应参数算法,针对遗传算法的不同阶段,实现杂交概率和变异概率的自适应调节,防止算法陷入局部最优解。最后,采用国际标准的TSP测试集(TSPLIB)对优化算法的优良性进行验证,实验表明,对比其他算法,该优化算法在TSP最优解的质量上提高10%左右。  相似文献   

6.
为了提高运输规划问题的有效性,降低运输成本,将遗传算法引入到该问题的求解中。运输规划问题的数学模型是带约束的函数优化问题,在该问题模型中引入遗传算法,采用罚函数法处理约束条件,对可行解和不可行解采用不同的适应值函数,结合轮盘赌、竞标赛和精英保存算法作为选择策略,对可行解和不可行解分别采用边界变异和非均匀变异,最终得出最优解。实验结果数值说明该方法的有效性。  相似文献   

7.
首先分析WF-Net中存在的隐含任务问题,然后基于α算法,提出了能发现工作流日志中隐含任务的过程挖掘算法α+**。该算法利用任务间特定的相互依赖关系判定是否存在隐含任务,然后把隐含任务添加到对应的位置生成新日志。最后采用α算法从新日志中提取出工作流网。利用ProM对本算法进行了验证。  相似文献   

8.
在大型流媒体数据库数据集中,交叉性数据的鲁棒性挖掘结构建立是实现对数据库差异属性分类和数据访问的基础。传统方法对大型数据库中的交叉性数据的鲁棒性挖掘结构建模采用基于遗传算法的数据集聚调度方法,存在较大的路径损耗,数据挖掘的鲁棒性不好。提出改进的基于局部离群点检测遗传进化的大型数据库交叉型数据挖掘模型,构建基于遗传算法的大型流媒体数据库挖掘结构,进行大型流媒体数据库中交叉型数据信息流特征预处理,结合交叉性型数据的离群因子概念,调整流媒体数据调度的位置变换策略,实现交叉性数据的鲁棒性挖掘算法改进。仿真实验结果表明,该算法能有效数据挖掘的a最大匹配率和局部离群点检测性能,保证了数据挖掘的鲁棒性,各项参数指标优于传统方法,展示了较好的应用价值。  相似文献   

9.
以图论和遗传算法为基础,提出了求最小生成树问题的基于节点编码的遗传算法.该算法采用Prufer数对最小生成树进行编码.初始群体由系统随机产生,在遗传操作中采用单点交叉操作及基本位变异操作.实例表明,该算法可得到多个最优解.  相似文献   

10.
赵海军 《情报杂志》2005,24(2):26-27,30
基于遗传算法 (GA) ,提出了一种新的知识挖掘系统。该系统以遗传算法为核心 ,解决一组属于面向对象数据库的对象所具有的共性问题。阐述了一种基于基因算法的知识发现系统的关键部分 ,描述了遗传算法 ,并通过一个实例说明了使用GA算法产生最佳查询方法的有效性。  相似文献   

11.
研究了多机协同多目标攻击空战决策问题。它是依据空战形势,寻求M架友机对N架敌机的一个适当的攻击分配方案,以实现最优的期望攻击效果。为此,本文首先建立了决策问题的数学模型,接着应用混合自适应遗传算法对其进行求解。在混合自适应遗传算法中,将一种局部搜索方法引入自适应遗传算法以提高其搜索能力。同时,设计了用于满足决策问题的非常规交叉算子。仿真实验结果表明所设计的混合自适应遗传算法比自适应遗传算法能更有效的解决协同多目标攻击空战决策问题。  相似文献   

12.
Recently, the augmented complex-valued normalized subband adaptive filtering (ACNSAF) algorithm has been proposed to process colored non-circular signals. However, its performance will deteriorate severely under impulsive noise interference. To overcome this issue, a robust augmented complex-valued normalized M-estimate subband adaptive filtering (ACNMSAF) algorithm is proposed, which is obtained by modifying the subband constraints of the ACNSAF algorithm using the complex-valued modified Huber (MH) function and is derived based on CR calculus and Lagrange multipliers. In order to improve both the convergence speed and steady-state accuracy of the fixed step size ACNMSAF algorithm, a variable step size (VSS) strategy based on the minimum mean squared deviation (MSD) criterion is devised, which allocates individual adaptive step size to each subband, fully exploiting the structural advantages of SAF and significantly improving the convergence performance of the ACNMSAF algorithm as well as its tracking capability in non-stationary environment. Then, the stability, transient and steady-state MSD performance of the ACNMSAF algorithm in the presence of colored non-circular inputs and impulsive noise are analyzed, and the stability conditions, transient and steady-state MSD formulas are also derived. Computer simulations in impulsive noise environments verify the accuracy of theoretical analysis results and the effectiveness of the proposed algorithms compared to other existing complex-valued adaptive algorithms.  相似文献   

13.
In this paper, a novel augmented complex-valued normalized subband adaptive filter (ACNSAF) algorithm is proposed for processing the noncircular complex-valued signals. Based on the augmented statistics, the proposed algorithm is derived by computing a constraint cost function. Due to contain all second-order statistical properties, the ACNSAF algorithm can process the circular and noncircular complex-valued signals simultaneously. Moreover, the stability and mean square steady-state analysis of the proposed algorithm is derived by using the energy conservation principle. Computer simulation experiments on complex-valued system identification, prediction and noise cancelling show that the proposed algorithm achieves the improved mean square deviation and prediction gain compared to the ACNLMS algorithm. And the simulation results are consistent with the analysis results.  相似文献   

14.
提出一种基于自适应遗传模拟退火策略的Web日志关联规则挖掘算法。该算法在遗传模拟退火策略基础上,引入自适应的交叉概率和变异概率,使其具有较强的全局搜索能力,有效地避免了早熟的现象。实验结果证明,该算法能有效地解决Web日志关联规则挖掘问题。  相似文献   

15.
The conventional interacting multiple model (IMM) algorithm will increase the computational load when applying a large number of models, meanwhile, it cannot yield accurate estimation results with a small number of models. Furthermore, the unknown target acceleration is regarded as an additional process noise to the target model, and its time-varying variance is hard to be approximated. The paper proposes a fuzzy-logic adaptive variable structure multiple model (FAVSMM) algorithm for tracking a high maneuvering target. The algorithm can optimize the model parameters using the model probability and construct an optimal model set quickly, and the fuzzy-logic IMM algorithm included in the FAVSMM algorithm is adopted for states estimation. The simulation results show that the proposed algorithm can match well with the actual target trajectory with less computational complexity and better accuracy.  相似文献   

16.
为了有效求解TSP问题,提出一种融合蚁群算法、遗传算法、粒子群优化算法思想的混合算法。该算法基于最大-最小蚁群系统框架,在选择下一个城市时采用局部搜索策略避免陷入局部最优,在每次循环结束时用演化交叉策略优化得到的全局最短路径,从而提高求解TSP问题的求解精度及收敛速度。TSPLIB中不同规模的TSP问题的仿真实验结果表明了该算法的有效性与可行性。  相似文献   

17.
This paper describes the application of the genetic algorithm for the optimization of the control parameters in parallel hybrid electric vehicles (HEV). The HEV control strategy is the algorithm according to which energy is produced, used, and saved. Therefore, optimal management of the energy components is a key element for the success of a HEV. In this study, based on an electric assist control strategy (EACS), the fitness function is defined so as to minimize the vehicle engine fuel consumption (FC) and emissions. The driving performance requirements are then considered as constraints. In addition, in order to reduce the number of the decision variables, a new approach is used for the battery control parameters. Finally, the optimization process is performed over three different driving cycles including ECE-EUDC, FTP and TEH-CAR. The results from the computer simulation show the effectiveness of the approach and reduction in FC and emissions while ensuring that the vehicle performance is not sacrificed.  相似文献   

18.
给出一种结合梯度法和正交遗传算法的混合算法。实验表明,它通过对问题的解空间交替进行全局和局部搜索,能更有效地求解函数优化问题。  相似文献   

19.
针对主题搜索引擎反馈信息主题相关度低的问题,提出了将遗传算法与基于内容的空间向量模型相结合的搜索策略。利用空间向量模型确定网页与主题的相关度,并将遗传算法应用于相关度判别,提高主题信息搜索的准确率和查全率。在Heritrix框架基础上,利用Eclipse3.3实现了相应功能。实验结果表明,搜索策略改进后的系统抓取主题页面所占比例与原系统相比提高了约30%。  相似文献   

20.
A rule-based energy management strategy, that the control rules are extracted from acknowledged optimal algorithms and its control parameters are optimized offline and corrected online, for a series-parallel hybrid powertrain with an automatic mechanical transmission (AMT) is proposed in this paper to achieve near optimal fuel economy and battery state-of-charge (SOC) balance. Firstly, the dynamic programming (DP) global optimization method is applied to extract driving-mode transition rules and gear shifting rules. Furthermore, an instantaneous equivalent fuel consumption minimizing optimization method (ECMS) is utilized to determinate the engine torque distribution rules during its parallel driving mode. Then selected control parameters of driving-mode switching rules and torque split distribution are optimized based on genetic algorithm (GA) for further fuel consumption improvement. And the adaptive correction of optimized control parameters based on online driving cycle recognition method is discussed also. The simulation results show that this real-time rule-based energy management control strategy associated with the series of optimization approaches comprehensively can achieve a relatively close fuel consumption results to global optimal results and sustain the battery SOC balance after the end of driving cycle without much cycle-depending care.  相似文献   

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