交叉概率对遗传算法运算速度影响的测试与分析

在现有文献基础上,通过理论分析,提出了交叉概率应取1.通过4个测试函数的测试结果,表明交叉概率越大,运算速度越快,平均运行代数越少,验证了通过理论分析提出的交叉概率应取1的科学性和可行性.同时克服了交叉概率难以确定以及确定交叉概率时缺少理论依据的不足.     

关于“SAS软件包中Fisher精确检验方法的分析”一文的争鸣意见

本文对ＳＡＳ软件包中精确概率的算法与一般统计学教科书有较大差别的问题提出了个人看法。认为在一般情况下根据ＳＡＳ软件包给出的双尾概率作出双侧检验结论时应取慎重态度     

用改进遗传算法求解矩阵实特征值

依据矩阵特征值的分布理论,通过确定矩阵实特征值的分布区域,用实数编码和具有自适应交叉概率和变异概率的遗传算法来求解矩阵实特征值的近似值.仿真结果表明,此算法可以达到一定的精度,具有一定的通用性.并给求矩阵特征值提供了一种快速的方法.     

基于改进遗传算法的多机调度问题

遗传算法是解决多机调度组合优化问题最有效的方法之一,但由于其自身存在着一定的缺陷应用受到一定的限制.针对遗传算法的“早熟”和非均匀地在优化空间中搜索等缺陷,提出了一种自适应选择交叉概率、变异概率以及交叉位置非等概率选取的改进的遗传算法,并将其用于某钢管钢绳企业的多机调度问题,进行了仿真分析.     

学习时间的数学模型与概率分布

根据长期教学经验总结建立出学习量与时间的关系曲线.通过曲线讨论了学习知识过程中所获知识量的时间分配和关键时间点,对学习者或教育者提出在自学或教学中关键时间点起的作用.后将学习曲线引入到概率理论分析,提出学习时间分布和密度函数观点,从而运用概率理论研究学习与时间的关系.     

概率推理系统与证据理论对应方法的改进

通过研究R.Haenni的概率推理系统和D-S理论的联系,提出了一种新的构造信任势的方法,使得概率推理系统与D-S信任势相对应,有效减少了信任势焦元的数量并给出理论证明.     

基于正余双弦自适应灰狼优化算法的医药物流配送路径规划

针对传统灰狼优化算法易早熟收敛陷入局部最优和收敛速度慢的缺陷,提出一种正余双弦自适应灰狼优化算法.首先,在灰狼捕食阶段引入正弦搜索,增强算法的全局勘探能力,减少算法的搜索盲点,提高算法的搜索精度.在引入正弦搜索的同时,引入余弦搜索,增强算法的局部开发能力,提高算法的收敛速度.其次,在搜索过程中加入自适应交叉变异机制,通过适应度值的大小自适应选取交叉变异概率,有效的提高了粒子跳出局部最优的概率.通过数值对比试验,验证了改进算法具有较强的收敛精度和收敛速度.     

二层线性规划的自适应遗传算法

提出了一种自适应遗传算法来求解二层线性规划问题.该方法克服了难以确定合适的交叉概率和变异概率的困难.另外,在该方法中还采用了其它一些技巧不仅解决了在采用遗传算法经常出现的有些个体不可行的问题,而且还改进了算法的效率.     

基于CREAM的飞行控制系统人机概率安全评估方法

针对目前系统概率安全评估中对人为差错研究的不足,重点讨论了考虑人为因素的飞控系统概率安全评估问题.首先针对飞行员操纵差错这一特定领域,提出了基于CREAM理论的飞行员操纵差错概率量化方法.在此基础上通过DFT建模与Monte-Carlo仿真对飞控系统进行人机概率安全评估.最后通过实例计算验证了该方法的有效性和实用价值,初步解决了人机系统概率安全评估难题.     

基于模糊数的模糊事件概率的结构元表示

Zadeh[1]定义了在概率清晰和事件模糊条件下,模糊事件的概率表示.不过,用[1]表示概率,求解繁杂且困难.为此,利用结构元理论,定义了模糊数事件概率的表达式.不仅证明其与经典定义等价,且证明了模糊数事件复合表达形式.最后,给出了关于模糊数不等式的概率的表达式.通过算倒可看出,运用本方法求解模糊数事件概率比较简捷.     

遗传算法的一种改进进化策略

在现有文献研究的基础上,对传统遗传算法的进化策略又作了进一步研究,提出了一种改进的进化策略.进化策略克服了传统遗传算法中交又得到的优秀个体有可能在变异过程中遭到破坏而不能生存的不足.另外取消了遗传算法中难以确定的交叉、变异概率,使交叉产生的新个体数增多,这样可增大产生更优秀个体的可能性,因而可使遗传算法的性能得到更好的改善.通过4个测试函数的测试计算,结果表明,给出的改进进化策略比传统遗传算法进化策略的运算速度明显提高,迭代次数明显减少,从而验证了提出的改进进化策略的有效性.     

A comparative study of crossover in differential evolution

In order to understand the role of crossover in differential evolution, theoretical analysis and comparative study of crossover in differential evolution are presented in this paper. Two new crossover methods, namely consecutive binomial crossover and non-consecutive exponential crossover, are designed. The probability distribution and expectation of crossover length for binomial and exponential crossover used in this paper are derived. Various differential evolution algorithms with different crossover methods including mutation-only differential evolution are comprehensively compared at system level instead of parameter level. Based on the theoretical analysis and simulation results, the effect of crossover on the reliability and efficiency of differential evolution algorithms is discussed. Some insights are revealed.     

改进的二进制粒子群算法求解车辆路径问题

设计了一种改进的二进制粒子群优化算法来求解车辆路径问题,算法基于粒子群算法的寻优模式充分考虑粒子之间的导向作用,改进二进制粒子群算法的位取值方式,减小了在进化过程中停滞于局部最优解的概率,并通过构造辅助函数处理优化问题的约束条件,基于分层次实现多个目标的思路来寻优,提高了算法的搜索效率和计算速度.实验测试结果验证了该算法对求解车辆路径问题的适用性和有效性.     

基于VIKOR和关联系数的犹豫三角模糊语言多属性决策方法

针对属性评价值为犹豫三角模糊语言集的多属性决策问题,提出一种基于VIKOR方法的犹豫三角模糊语言多属性决策方法.首先定义了犹豫三角模糊语言集的相关概念.然后运用VIKOR和关联系数方法,在可接受优势和决策过程稳定的条件下对方案进行择优,在理论分析的基础上,提出了这种新方法的计算步骤.并构建了确定最优属性权重的非线性规划模型,研究了当专家权重和属性权重未知情况下的犹豫三角模糊语言多属性决策方法.最后通过实例说明了该方法的有效性和可行性.     

Approximate calculation method for one-dimensional gas flows induced by nonmonotonic motion of a piston : PMM vol. 40, n 6, 1976, pp. 1058–1064

The problem of one-dimensional piston which at the beginning moves with increasing velocity into a gas at rest, then is decelerated, and finally stops, is solved by means of special series. The gas flow field is constructed by a successive joining of three characteristic Cauchy problems in terms of their characteristic solutions. Generalized solution of the problem of instantaneous arrest of the piston is derived. Obtained equations are used for the approximate calculation of the motion of generated shock waves.Representation of solutions of certain boundary value problems for nonlinear equations of the hyperbolic kind in the form of special series was proposed in [1, 2], The problem of the piston moving into a gas at rest is solved there, and the obtained solution was used for an approximate determination of the generated shock wave. The piston velocity was assumed to be monotonically increasing. That problem is solved here with the use of similar series in the case when the piston velocity is nonmonotonous,Numerical methods make it possible at present to determine one-dimensional flows similar to that considered below, and multidimensional problems can be solved by the method proposed in [1, 2]. The use of the proposed scheme for solving the problem of the multidimensional piston, whose velocity is nonmonotonous, does not present theoretical difficulties, but except that the formulas are more cumbersome.     

离散回溯搜索算法求解多柔性作业车间调度

针对柔性作业车间生产中机器和工序柔性与多能工的存在建立模型,并提出一种整数编码方案和设一种基于Pareto解集的离散回溯搜索算法进行求解。首先,采用精英化历史种群的方法提升历史种群引导当前种群进化的能力;其次,在交叉变异步骤用遗传交叉算子替代回溯搜索算法原有结构;再次,为保留更多较优解到当前种群,结合快速非支配排序方法更新当前种群;最后,求解数值实例,与多种智能算法进行对比,验证算法的可行性和有效性。     

Differential evolution using a superior–inferior crossover scheme

Differential evolution (DE) is a new population-based stochastic optimization, which has difficulties in solving large-scale and multimodal optimization problems. The reason is that the population diversity decreases rapidly, which leads to the failure of the clustered individuals to reproduce better individuals. In order to improve the population diversity of DE, this paper aims to present a superior–inferior (SI) crossover scheme based on DE. Specifically, when population diversity degree is small, the SI crossover is performed to improve the search space of population. Otherwise, the superior–superior crossover is used to enhance its exploitation ability. In order to test the effectiveness of our SI scheme, we combine the SI with adaptive differential evolution (JADE), which is a recently developed DE variant for numerical optimization. In addition, the theoretical analysis of SI scheme is provided to show how the population’s diversity can be improved. In order to make the selection of parameters in our scheme more intelligently, a self-adaptive SI crossover scheme is proposed. Finally, comparative comprehensive experiments are given to illustrate the advantages of our proposed method over various DEs on a suite of 24 numerical optimization problems.     

基于替代数据法和MF-DFA的合意工业产能利用率区间估计方法及应用

为实现工业产能过剩的精准判别与调控，提出了一种基于替代数据法与多重分形去趋势波动分析的合意工业产能利用率区间估计方法。首先判断原始时序的长程相关性和多重分形特征；然后采用替代数据法与多重分形去趋势波动分析计算出所有重排序列的Hurst指数，据此确定指数序列收敛情况和合意产能利用率区间；最后以煤炭行业为例验证了模型的有效性。结果表明：该方法能够从数据自身演化规律中自适应确定阈值，有效克服了传统统计与经验方法的主观性和缺乏理论依据的局限性；我国煤炭行业的合意产能利用率区间为73.73%～86.23%。该研究为工业产能过剩风险监测与判别提供了量化分析工具，为深化煤炭产能过剩治理提供了决策依据。     

Economical and ecological utility oriented analysis of the process of anaerobic digestion of waste waters

A problem which has been constantly emphasized is the creation of criteria adequate to characterize the complexity of ecological analysis. The objective of the present paper is to demonstrate the capabilities of multiattribute utility theory in difficult-to-formalize problems. The multiattribute utility and the proposed algorithms provide a logically and operationally tested method which includes value in complex ecological problems. The results obtained and the constructed utility functions should be accepted as an iterative stage in real investigations, rather than as complete research that offer a final decision. The value estimations of the decision maker are the basis for interest in a given ecological problem. But they are often not explicitly or consistently addressed in the real investigations. The proposed methods account for otherwise uninterpretable information. The constructed value function can be used for automatic computer control and monitoring of anaerobic waste water digestion, which could reveal a new potential from the practical point of view.     

不同随机分布的相位随机化对实测数据影响的分析研究

本文对服从不同分布的随机数相位充分随机化后对动力系统实测数据生成的替代数据的影响做了分析研究，计算结果表明：不同分布的随机数相位充分随机化后对临界值无质的影响·这对相位随机化方法的可行性，实用性和广泛应用提供了理论依据，并对它对于实际问题的应用提供了具体的实施方法