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1.
蛙跳优化算法求解多目标无等待流水线调度   总被引:1,自引:0,他引:1  
提出了基于Pareto边界和档案集的改进蛙跳算法,解决以最大完工时间、最大拖后时间和总流经时间为目标值的无等待流水线调度问题.首先,采用NEH(Nawaz—Enscore—Ham)启发式与随机解相结合的初始化方法,保证了初始群体的质量和分布性;其次,采用两点交叉方法生成新解,使蛙跳算法能够直接用于解决调度问题;再次,利用非支配解集动态更新群体,改善了群体的质量和多样性;最后,将基于插入邻域的快速局部搜索算法嵌入到蛙跳算法中,增强了算法的开发能力和效率.仿真试验表明了所得蛙跳算法的有效性和高效性.  相似文献   

2.
针对无等待批量流水线调度问题,根据和声算法的机理,提出了一种改进的和声算法对其进行求解。利用NEH和混沌序列相结合的方法产生初始解,并实现了和声向量与工序之间的转换;充分利用最优解,设计新的更新算子,为了避免陷入局部最优,引入了变异策略;结合蛙跳算法分组的特点,将和声库随机动态的分成了几个子和声;为平衡算法的全局开发和局部搜索的能力,对子和声中的最优解执行了局部搜索。通过仿真实验与其他几种算法进行比较,证明了算法的有效性。  相似文献   

3.
基于蛙跳算法的零空闲流水线调度问题优化   总被引:2,自引:0,他引:2       下载免费PDF全文
针对零空闲流水线调度问题,以E/T指标最优为优化测度,提出了一种蛙跳求解算法。首先,该算法采用新的个体产生方法,扩展传统蛙跳算法的求解模型。其次,使用带有启发式策略的种群初始化方法优化初始解性能。再次,借助基于种群多样性的方法进行排序和分组,并通过部分随机初始化策略保持种群多样性。最后,结合一种简单而有效的邻域搜索算法,达到局部探索和全局搜索之间的平衡,进而提高收敛速度。在若干benchmark问题上的仿真实验表明了所提算法的有效性。  相似文献   

4.
针对批量流水线调度问题,提出了一种改进的人工蜂群算法来优化最大完成时间。该算法运用NEH方法产生初始解,采用混沌遍历的方法生成新的邻域解。为了跳出局部最优,使用最优解的插入扰动来替换一些连续若干步不能改进的解来提高算法的全局搜索能力。采用自适应的局部搜索加强算法的局部搜索能力。仿真试验表明了所得算法的可行性和高效性。  相似文献   

5.
针对流水车间调度问题提出一种混合遗传NEH算法,以提高求解效率.NEH算法是一种高效的构造性算法具有很强的邻域搜索能力,而遗传算法则能有效地提供全局搜索.据此,新算法首先通过选择、交叉和变异操作,经过迭代获得一个较好解,然后在这个解所在的特定邻域内进行改进的NEH搜索,以获得更好解,经过NEH搜索后求得的最好解作为一个新个体加入下一代种群中,继续进行遗传操作.通过对流水车间调度的最小化最大完成时间问题的仿真实验结果表明,新算法有明显改进.  相似文献   

6.
求解置换流水车间调度问题的改进遗传算法   总被引:1,自引:0,他引:1       下载免费PDF全文
针对置换流水车间调度问题的基本特征和传统遗传算法易早熟的缺陷,设计了改进遗传算法来求解此问题。采用NEH和Palmer启发式算法进行种群初始化,以提高初始解的质量;根据Metropolis准则对染色体进行选择操作,避免陷入局部最优;在变异过程中引入禁忌算法,避免迂回搜索;在算法迭代过程中引入了保优机制,避免丢失优秀染色体的基因信息;采用自适应终止准则,以保证解的质量。基于典型Benchmark算例的仿真实验结果表明,算法在求解质量和收敛速度方面明显优于NEH算法和种群经过初始优化的传统遗传算法。  相似文献   

7.
针对流水车间批调度问题,提出一种基于群智能算法的求解思路。结合问题具体特点,给出工件集合的分批策略,设计了将Palmer和Best Fit(BF)分批规则相结合的分批方法;在批排序阶段,提出了一种改进的微粒群算法;在粒子初始生成阶段,通过引入NEH启发式算法改进了粒子的初始化质量;在全局最佳位置更新前,通过变邻域搜索优化了算法的局部搜索能力,避免了算法陷入局部最优。仿真实验表明,改进后的算法优于传统的微粒群算法和NEH启发式算法。  相似文献   

8.
将离散微粒群与蛙跳算法相结合解决以最大完工时间为指标的批量无等待流水线调度问题.结合微粒群算法较强的全局收敛能力和蛙跳算法较强的深度搜索能力,设计了三种混合算法,平衡了算法的全局开发能力和局部探索能力.对随机生成不同规模的实例进行了广泛的实验,仿真实验结果的比较表明了所得混合算法的有效性和高效性.  相似文献   

9.
针对基本蚁群算法存在容易陷入局部最优解出现早熟停滞状态的缺点,提出了基于混合蛙跳思想的蚁群算法,并应用于城市交通路径寻优研究。通过引入混合蛙跳算法的全局信息共享和局部深度搜索机制,提高了蚁群算法跳出局部最优解的能力与全局收敛性。以重庆市渝中半岛的路网为实例计算以行程时间为目标的最优路径,实验结果表明该算法有效改善了基本蚁群算法的全局搜索能力,同时为解决城市交通路径寻优问题获得了较好的效果。  相似文献   

10.
双目标无等待流水线调度的加权混合算法   总被引:1,自引:0,他引:1  
谈超  李小平 《计算机科学》2008,35(11):199-202
针对最小化“总完工时间”和“最大完工时间”的双目标无等待流水线作业调度问题提出了一种粒子群加权混合优化算法,通过随机加权的方式将其转换成单目标问题,并应用基于升序排列的ROV(ranked-order-value)编码规则,将粒子群优化算法应用于无等待流水线作业调度问题。为了提高算法的性能,增强算法的搜索能力,提出的混合算法应用了NEH方法构造初始种群,在一个较好的初始值上进行粒子群优化,为防止种群陷入局部最优造成早熟,在粒子群每次迭代之后对全局最优解加入扰动并进行变邻域搜索。仿真实验结果表明该混合调度算法具有良好的性能。  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.
蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。  相似文献   

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