一种基于差异演化变异的粒子群优化算法

为了保持粒子种群的多样性而避免发生“早熟”的问题,提出一种基于差异演化变异的粒子群优化算法（PSO）,该方法通过粒子聚集性判断如果粒子群中的粒子过于聚集,则使用差异演化算法对PSO算法中各个粒子的自身历史最佳位置进行变异,以实现保持粒子群种群多样性的目的。对4种常用函数的优化问题进行测试并进行比较,结果表明：所改进的粒子群优化算法比标准粒子群优化算法更容易找到全局最优解,优化效率和优化性能明显提高。     

带可变随机函数和变异算子的粒子群优化算法

标准粒子群优化算法的收敛分析表明,改变随机函数、个体历史最优,群体全局最优,有助于提高该算法的性能。为此,本文提出了一种带可变随机函数和变异算子的粒子群优化算法,即通过改变速度更新方程中的随机函数分布来调节粒子在迭代过程中飞向个体历史最优和群体全局最优的比重,通过对个体历史最优和群体全局最优进行变异来增强种群的搜索能力。实验结果证实了该算法的有效性。     

基于种群多样性模糊控制的粒子群算法

关于优化粒子群算法问题,针对标准粒子群算法前期收敛速度过快,后期容易陷入局部最优解的问题,提出一种种群多样性模糊控制的粒子群算法。为了控制种群多样性的变化,提高算法跳出局部最优解的性能,在算法中加入模糊控制器和位置跳变策略,通过控制参数的变化来控制粒子的速度、位置和种群多样性的变化,使算法从全局探测平稳过渡到局部开采。仿真结果表明,改进算法能有效避免陷入局部最优解,且对高维函数优化时效果更为明显,是一种高效的优化算法。     

基于种群关系的多种群粒子群协同优化算法

传统粒子群优化算法容易陷入局部最优解,搜索效率不高,针对此问题,提出了一种基于种群关系和斥力因子的多种群粒子群优化算法SRB-PSO (Swarm-Relation-Based PSO).根据当前搜索结果定义种群之间统治、对等和被统治3种关系,通过引入斥力因子来保证种群间搜索的多样性,并通过统治和被统治关系提高算法的搜索效率,从而在改善算法的全局搜索性能的同时提高解的质量.将算法与其他几种主流粒子群优化改进算法在标准测试集上进行对比,实验结果证明了SRB-PSO算法能较好地保持粒子多样性,全局搜索能力强,在解决多峰函数时的性能优于其他几种主流粒子群优化改进算法.     

吸引子权重改变内嵌区域震荡搜索粒子群算法

针对粒子群算法搜索精度不高、搜索最优解较慢的问题,提出了一种改进的粒子群算法。该算法通过调整全局最优解和个体最优解,形成一个新的全局吸引子解指导粒子收敛,优化种群粒子来搜索解空间的最优值。再将优化方案融入到内嵌区域震荡搜索的粒子群算法（RSPSO）中,仿真结果表明,改进的粒子群算法在寻优能力及搜索精度方面都得到了进一步的提高。     

改进粒子群算法的三维空间路径规划研究

提出一种自适应混沌粒子群优化算法（SACPSO）用于三维空间路径规划。首先进行三维空间环境建模，并考虑使用路径长度、障碍物危险程度和路径平滑度三个评价函数来制定适应度函数；然后对算法中的三个控制参数提出了一种新的自适应更新策略，以此来动态调整算法的全局探索和局部开发能力；最后当种群陷入局部极值时，利用提出的自适应Logistic混沌映射对全局最优粒子进行混沌优化，引导种群跳出局部极值点。将该算法与其他改进的粒子群算法比较，结果表明，该算法在收敛到全局最优解时所用迭代次数更少，生成路径质量更高，有效地提高了粒子群算法应用于三维空间路径规划时的计算效率和可靠性。     

一种新型的动态粒子群优化算法

为了改进标准粒子群优化算法全局搜索性能,提出了一种种群动态变化的多种群粒子群优化算法。当算法搜索停滞时,把种群分裂成2个子种群,通过子种群粒子随机初始化及个体替代机制增强种群多样性,两个子种群并行搜索一定代数后,通过混合子种群来完成不同子种群中粒子的信息交流。收敛性分析表明,本文算法能以概率1收敛到全局最优解。实验结果表明,本文算法具有较好的全局寻优能力和较快的收敛速度。     

基于双种群交叉学习的粒子群优化算法

粒子群优化算法因其支配参数少、收敛速度快、易于实现等特点被广泛应用,但是粒子群优化算法存在精度低、容易陷入局部优化的问题。为此提出一种基于双种群交叉学习的粒子群优化算法。在该算法中,整个种群被分为普通子种群和精英子种群。普通子种群采用综合变异机制,该机制通过设置概率参数使普通子种群随机选择朝着优秀粒子的方向或者保持自身方向进行变异,以侧重寻找可能解区域。精英子种群则采用交叉学习机制,将粒子的历史最优和全局最优个体进行交叉生成范例,从而引导粒子对可能解区域进行局部搜索,还提出了一种非线性惯性权重来平衡粒子的全局勘探和局部开发能力。为了验证算法的有效性,在十六个基准问题上进行测试并与其他七种粒子群优化算法变体比较,实验结果表明该算法在求解精度和收敛速度总体排名第一,验证了该算法求解性能优于其他粒子群优化算法变体。     

一种基于云模型的改进型粒子群算法

针对经典粒子群算法在函数优化中易陷入局部最优和早熟收敛等缺点,结合云模型在定性与定量之间相互转换的优良特性,提出一种基于云模型的改进型粒子群算法。其思想是通过反向学习机制初始化种群,再通过正态云算子求解粒子群中的全局最优个体和自身最优个体周围的更优值,最后利用混沌理论对个别粒子进行变异来跳出局部最优解。典型复杂函数测试表明,该算法能有效找出全局最优解,特别适宜于多峰值函数寻优。     

一种动态分组的粒子群优化算法

针对粒子群优化算法易陷入局部最优的问题,提出一种动态分组的粒子群优化算法.通过对鸟群习性的研究,给出交互粒子的概念,并在粒子群优化过程中引入动态分组机制,将种群动态划分成多个子种群,且每次划分的子种群数目是从特定集合中随机选取,从而增加交互粒子划分到同一子种群的概率.每个子种群在收敛进化的同时,利用环拓扑结构提高种群多样性及算法搜索全局最优解的能力.实验结果表明,与其他粒子群优化算法相比,该算法具有更好的稳定性、寻优性能以及更高的收敛精度.     

Only connect: teaching, technology and telesis

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.     

European Community policy and the market

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.     

一种自适应子融合集成多分类器方法

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。     

Avoiding semantic and temporal gaps in developing software intensive systems

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.     

Designing economic np control charts: A programmed simulation approach

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.     

The development of robot art

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     

Explanation and prediction: an architecture for default and abductive reasoning

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.     

Three Process Perspectives: Organizations, Teams, and People

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.     

基于复小波噪声方差显著修正的SAR图像去噪

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。     

How do children do mathematics with LOGO?

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.