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1.
种群动力学优化算法   总被引:2,自引:1,他引:1  
黄光球  李涛  陆秋琴 《计算机科学》2013,40(11):280-286
为了快速求解大规模复杂优化问题,基于种群动力学理论构造出了可全局收敛的种群动力学优化算法。在该算法中,每个种群对应着优化问题的一个试探解,种群的一个特征对应于试探解的一个变量;采用正交拉丁方原理构造出了种群初始值确定方法,以达到对搜索空间的均衡分散性和整齐可比性覆盖;将任意两种群间的竞争、互利、捕食-被食、融合、突变和选择等行为用于构造种群的进化策略,以使种群的适应度指数要么保持原状不变,要么向好的方向转移,从而确保整个算法的全局收敛性;在种群演变过程中,种群从一种状态转移到另一种状态,实现了种群对优化问题全局最优解的搜索。应用可归约随机矩阵的稳定性条件证明了本算法具有全局收敛性。测试结果表明本算法是高效的。  相似文献   

2.
为了解决某些函数优化问题,基于具有脉冲毒素输入的生态毒理动力学模型提出了可全局收敛的函数优化算法。在该算法中,令环境系统与优化问题的搜索空间相对应,该环境系统存在污染现象,污染源定期地向环境系统注入有毒污染物。有多种不同类型的种群生活在该环境系统中,不同类型的种群之间存在竞争关系和捕食-被捕食关系,每个种群对应着优化问题的一个试探解。将生态毒理动力学模型映射成对种群的特征的变化规律的描述,利用环境和种群以及种群与种群之间的相互作用构造种群的进化算子,这些算子从多种角度实现了种群与环境以及种群与种群之间的信息交换。结果表明:因环境污染影响的是种群的很少部分特征,当种群演化时,只涉及到很少一部分特征参与运算,故收敛速度可得到提升;环境系统脉冲式注入毒素,可以导致种群的特征状态值发生突然改变,这种特点有利于使搜索跳出局部最优解陷阱;使能够抵抗污染的强壮种群获得生长,而无法抵抗污染的虚弱种群则停止生长,此特点确保了该算法具有全局收敛性。测试结果表明:对某些函数优化问题的求解,本算法与已有的群智能优化算法相比,均具有较高的精度和性能。  相似文献   

3.
《计算机科学与探索》2017,(10):1689-1700
为了解决复杂函数优化问题,提出了一种Lotka-Volterra生态平衡动力学优化算法。该算法假设在某个生态系统中有自养者、消费者和分解者3个种群。自养者主要是植物;消费者主要是以自养者为食的动物;分解者主要分解消费者的死有机体,并给自养者提供营养物质。根据上述生态系统中种群的关系构造出了消费者-自养者算子、自养者-分解者算子、分解者-消费者算子和生长算子。自养者、消费者和分解者种群的生长变化相当于搜索空间的试探解从一个位置转移到另外一个位置。该算法具有搜索能力强和全局收敛性的特点,为复杂优化问题的求解提供了一种解决方案。  相似文献   

4.
为了快速求解大规模优化问题,构造出了可全局收敛的蝙蝠算法。在该算法中,将一个蝙蝠看成是优化问题的一个候选解;采用正交拉丁方原理生成蝙蝠群的初始空间位置,以达到对搜索空间的均衡分散性和整齐可比性覆盖;将蝙蝠的追随、自主、避险和从众行为用于构造每个蝙蝠的空间位置转移策略;利用蝙蝠捕获猎物时的响度和脉冲速率来确保整个蝙蝠群要么保持原状态,要么向好的空间位置转移,但绝不会向差的空间位置转移。在蝙蝠群移动过程中,蝙蝠从一个空间位置转移到另一个空间位置实现了蝙蝠群对优化问题最优解的搜索。结果表明,采用可归约随机矩阵稳定性定理可证明本算法具有全局收敛性。测试案例表明,本算法用于求解大规模优化问题时具有对不同类型优化问题适应性强且收敛速度快的优势。  相似文献   

5.
为了求解一些复杂优化问题的全局最优解,基于保护区种群迁移动力学模型,提出了一种新的群智能优化算法,简称PZPMDO算法。在该算法中,假设有很多生物种群生活在某生态系统中,该生态系统被分成两个区域,即非保护区和保护区,对生活在保护区内的生物种群实施各种保护。在非保护区与保护区之间存在种群迁移通道,若某区域内的某生物种群的密度过高,该生物种群就会自发地迁移到低密度区域,从而导致低密度区域内的生物种群受到迁移过来的生物种群的影响;若某生物种群的占比越大,该生物种群的影响也就越大;若某生物种群越强壮,该生物种群就越会将其优势传播给其他生物种群。不同区域内的各生物种群因生存竞争而相互影响,这种影响会体现在种群部分特征间的相互作用上,且该影响是随时间变化的。文中采用ZGI指数描述一个生物种群的强弱程度,利用保护区种群迁移动力学模型、种群迁移和相互影响关系构造算子。PZPMDO算法拥有8个算子,且演化时每次仅处理总变量数的1/1000~1/100,具有搜索速度快和全局收敛性的特点,适用于求解维数较高的全局优化问题。  相似文献   

6.
为了求解一些非线性优化问题的全局最优解,采用水平结构竞争-互利群落动力学理论,提出了一种新的水平结构竞争-互利群落优化算法(HS-CBCO)。在该算法中,每个种群由若干生物个体组成,种群间相互作用主要是竞争和互利,种群内部各个体之间存在相互影响。运用群落动力学理论开发出了6个算子,其中竞争和互利算子可实现个体跨种群交换信息,而普通影响和强烈影响算子可实现种群内的个体之间的信息交换,从而确保了个体间的信息的充分交换;新生算子可适时补充新个体到种群中,而死亡算子可将种群中的虚弱个体适时清除掉,从而提升了该算法跳出局部陷阱的能力。测试结果表明,HS-CBCO算法的求精能力、探索能力及其两者的协调性均优良,且具有全局收敛性的特点,为复杂优化问题全局最优解的求解提供了解决方案。  相似文献   

7.
为了求解一类复杂非线性优化问题的全局最优解,基于采用垂直结构群落动力学理论,提出了一种新的垂直结构群落系统优化算法,简称为VS-CSO算法。该算法将优化问题的搜索空间视为一个生态系统,该生态系统具有若干个垂直结构分叉营养水平,在各个营养水平中生活着不同种类的生物种群;在每个种群内,有若干生物个体在活动;生物个体不能跨种群迁移,但在同类种群中会相互影响。各种群以循环捕食-被食或资源-消耗连接在一起。运用垂直结构群落动力学模型开发出了通吃算子、择食算子、干扰算子、侵染算子、新生算子、死亡算子。其中,通吃算子和择食算子可实现个体跨种群的信息交换,而干扰算子和侵染算子可实现种群内部个体之间的信息交换,从而确保个体间信息的充分交换;新生算子可适时补充新个体到种群中,而死亡算子可将种群中的虚弱个体适时清除掉,从而大幅提升算法跳出局部陷阱的能力。在求解过程中,VS-CSO算法每次只对极少变量进行处理,因此可求解高维优化问题。测试结果表明,VS-CSO算法能求解一类非常复杂的单峰函数、多峰函数和复合函数优化问题,其求精能力、探索能力及两者的协调性均优良,且具有全局收敛性的特点。该算法为求解一些较高维复杂函数优化问题的全局最优解提供了可行方案。  相似文献   

8.
提出一种求解多目标最小生成树问题的有效离散粒子群优化算法.为获得更好的非劣前端,设计一个基于目标共享函数的适应度评价函数.引入遗传算法的变异和交叉算子,提高种群多样性并避免算法过早陷入局部最优解.基于种群的随机状态转移过程,理论分析算法的全局收敛性.实验结果表明该算法是有效的,且随着问题规模的扩大算法仍保持较好的性能.  相似文献   

9.
基于生态毒理动力学模型构造出可全局收敛的函数优化算法。在该算法中,将优化问题的搜索空间看成一个存在污染现象的环境系统,将一个试探解看成一个种群,采用生态毒理动力学模型对种群生长特征的变化规律进行描述。种群在污染作用下不断发生变化,能够抵抗住污染的强壮种群能够获得生长,而无法抵抗住污染的虚弱种群则停止生长。用环境和种群以及种群与种群之间的相互作用关系构造进化算子,这些算子从多种角度实现了种群之间的信息交换。因环境污染影响的是种群的很少部分特征,当种群演化时,只涉及到很少一部分种群特征参与运算,故提高了算法的收敛速度。测试结果表明本算法的精度和性能优于已有的群智能优化算法。  相似文献   

10.
为了求解一些非线性优化问题,采用具有脉冲出生和季节性捕杀的种群动力学模型提出了一种新的群智能优化算法(PSO-IBSK).在该算法中,假设某种群由具有幼年和成年两种阶段状态的若干个体组成,幼体是由成体脉冲产生的,经过一段时间后会变成为成体.为了提升种群的整体质量,需要季节性地对一些生长状况不良的成体进行捕杀.该算法中的出生算子和成长算子可分别实现成体向幼体瞬时和延迟传递信息,有助于搜索跳出局部最优解陷阱;捕杀算子可周期性地将不良成体清除,死亡算子可将虚弱个体随机清除,该两个算子有利于提升算法的求精能力;强势算子可实现强壮个体向虚弱个体扩散强壮信息,竞争算子可实现幼年和成体之间的有效信息交换,该两个算子有利于提升算法的探索能力;进化算子可确保算法具有全局收敛性.该算法的大部分参数采用该种群动力学模型确定,具有很好的科学性;该算法每次只处理个体特征数的6‰~8%,从而使时间复杂度大幅降低.测试结果表明,该算法具有较优越的性能,适于求解维数较高的优化问题.  相似文献   

11.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

15.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

16.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

17.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

18.
This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)SM and Team Software Process (TSP){SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.  相似文献   

19.
基于复小波噪声方差显著修正的SAR图像去噪   总被引:4,自引:1,他引:3  
提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。  相似文献   

20.
Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.  相似文献   

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