自适应合并与分裂的多种群差分进化算法

针对差分进化（DE）算法存在的早熟收敛与搜索停滞问题,提出了自适应合并与分裂的多种群差分进化算法。算法将种群划分为多个子种群,引入子种群优劣因子来评价种群的优劣性,实现种群间的自适应合并与分裂;对于种群中的各个个体,采取基于精英池学习的变异算子,结合优秀个体进行自适应学习调整,使算法达到全局搜索与局部搜索能力的平衡;在算法后期引入扰乱策略,保证算法快速收敛的同时有效地跳出局部极值点,提高算法寻优的精度。在30个标准测试函数的实验结果表明,改进算法能有效解决早熟和陷入局部最优的问题。     

加权变异策略动态差分进化算法

针对差分进化算法在解决高维优化问题时易早熟收敛、求解精度低和参数设置麻烦等问题,提出一种加权变异策略动态差分进化算法（WMDDE）。为了动态平衡全局搜索与局部搜索能力,跳出局部最优,将标准差分进化算法的变异策略DE/rand/1和DE/best/1进行加权组合,提出两种新的随机扰动加权变异算子。提出一种动态自适应调整缩放因子和交叉概率因子的策略,避免参数设置的麻烦,提高算法的稳定性。在11个Benchmark函数上的测试结果表明,新算法能有效避免早熟收敛,全局寻优能力强,且在高维时寻优速度、求解精度和稳定性均优于4种DE进化算法。     

求解高维多模优化问题的正交小生境自适应差分演化算法

针对传统优化算法在求解高维多模态优化问题时存在收敛速度慢、求解精度低的问题,提出一种基于正交设计与小生境精英策略的自适应差分进化算法ONDE。首先利用正交表产生初始种群,然后采用小生境精英策略来产生小生境种群(NP),并用小生境种群更新精英个体;接着应用拥挤裁剪避免种群陷入局部搜索,最后利用自适应差分变异算子改进了差分进化(DE)算法。通过对7个benchmark函数仿真验证,实验结果表明,算法在收敛速度、求解精度和稳定性方面都有较大优势。     

改进差分进化算法辨识加药凝絮过程参数

针对标准差分进化算法收敛速度慢,容易陷入局部最优从而导致收敛精度不高的缺点,提出将DE/rand/1和DE/best/1线性加权相结合以及自适应重构交叉概率因子的改进差分进化算法.该算法中变异策略采用将DE/rand/1和DE/best/1通过线性模拟退火加权策略相结合,交叉因子则根据进化代数自适应重构,使得算法在初期重视全局搜索能力以找到全局最优可能解,后期重视局部收敛速度,以提高算法寻优能力和收敛速度.最后将该算法和其他改进差分进化算法用于城市供水水处理过程的加药凝絮参数辨识中,仿真结果表明,该算法相对于其他3种算法具有更快的收敛速度和更好的收敛精度,所得模型对检验数据的误差平方和很小,表明该模型准确可靠,为投药过程的前馈反馈控制和水厂的优化运行打下了良好基础,具有很好的实际意义.     

参数自适应的精英变异差分进化算法

针对经典差分进化算法(DE)的优化性能容易受到变异策略和控制参数影响的问题，提出了一种参数自适应的精英变异差分进化算法(A parameter Adaptive Elite Mutation Eifferential Evolution algorithm, AMEDE).首先，提出一种精英变异策略的方法，其目的是为了方便获取优秀个体信息；其次，引入新的控制参数，使得算法可以在更大的搜索空间进行搜索；最后，利用自适应参数学习方法，为种群中的每个个体赋予不同的控制参数值，并根据种群多样性和精英个体的信息动态更新个体的参数，使算法避免过早的收敛并提高算法的收敛精度.对本文提出的AMEDE算法与其他6种改进差分进化算法(DE,CoDE,JaDE,JDE,SaDE,GPDE)在16个基准测试函数上进行了三组对比实验.实验结果表明，AMEDE算法在高维函数和低维函数上都具有搜索精度高、收敛速度快和鲁棒性强等优点.     

基于新变异策略的动态自适应差分进化算法

针对差分进化算法在复杂优化问题求解时后期收敛速度慢、易陷入局部最优和参数设置繁琐等问题,提出一种基于新变异策略的动态自适应差分进化算法p-ADE.首先,新变异策略中通过利用种群的全局最优解和目标个体的历史最优解引导种群搜索方向,为下一代个体的生成引入更多有效的方向性信息,避免差分向量中个体随机选择导致的搜索盲目性.其次,为加快收敛速度、提高算法稳定性、避免参数设置的繁琐与不精确,提出一种参数动态自适应调整策略,动态平衡算法局部搜索与全局搜索间的关系,有效调节个体在进化过程中的变异程度.在10个Benchmark函数上的实验结果表明,p-ADE相对于多种先进DE优化策略和全局优化算法在收敛精度、速度和鲁棒性上均具有明显优势.     

多变异策略差分进化算法的研究与应用

标准差分进化(DE)算法在高维多峰等复杂函数优化时易出现早熟现象,并且算法后期收敛速度较慢。为此,研究2种标准差分进化算法的变异策略(DE/rand/1和DE/best/1),并将其进行串行组合,提出一种多变异策略的差分进化算法(MDE)。在4个Benchmark函数上的测试结果表明,在多变异策略下,通过对MDE算法控制参数的调整能有效拓展和平衡改进后算法的全局与局部搜索能力,其所得最优解的精度、算法的收敛速度都较标准差分进化算法有明显优势,能较好地解决电力负载分配问题。     

基于改进差分进化算法的机械臂运动学逆解

以9自由度液压机械臂为研究对象,建立求解位姿逆解的非线性方程组.以末端执行器位姿误差最小为优化指标建立目标函数,将非线性方程求解问题转化为最优化问题,并应用差分进化(DE)算法求解该问题.首先,为了避免位置和姿态收敛精度的不同,引入自适应权值系数进行平衡.然后,为克服基本DE算法难以平衡全局探索能力和局部开发能力的缺陷,结合DE/rand/1/bin和DE/best/1/bin两种进化模式,改进自适应变异差分进化(SAMDE)算法,提高了算法的收敛精度和收敛速度.最后,采用对称映射法对不满足关节角边界范围的个体进行处理,提高了收敛精度.开展了与基本DE算法的对比试验,仿真结果表明,该算法的收敛精度和收敛速度优于基本差分进化算法,且能够大幅度提高算法的稳定性.     

基于双变异模式协同的自适应微分进化算法

针对微分进化算法(DE)易陷入局部最优解、进化后期收敛速度慢、求解精度低等缺点,结合DE/rand/1和DE/best/1两种变异模式分别具有全局探索能力和局部开发能力的优点,引入精英存档策略和控制参数自适应策略,提出一种双变异模式协同自适应微分进化(DMCSaDE)算法.15个典型benchmark测试函数的实验结果表明,DMCSaDE能够有效提高算法的全局探索能力和局部开发能力,避免早熟收敛,大大提高算法的收敛性能和鲁棒性,同时,精英种群的大小对DMCSaDE的优化性能具有明显的影响.     

采用双变异策略的自适应差分进化算法及应用

为了克服差分进化算法早熟收敛和寻优精度低的缺点,提出一种采用双变异策略的自适应差分进化算法（Adaptive Differential Evolution Algorithm using Double mutation strategies,DADE）。DADE引入基于种群相似度和中心解的双变异策略,有效平衡了算法的全局搜索和局部搜索;自适应交叉概率使种群个体向更新成功的个体学习,有利于后续种群的进化。在7个测试函数和3个电力系统动态经济调度（Dynamic Economic Dispatch,DED）问题上的优化结果表明,DADE算法与其他4种DE算法相比具有更强的全局寻优能力,且对电力系统动态经济调度问题的优化结果优于文献中所报道的结果。     

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.