改进蚁群算法FENA2O解决TSP问题研究

为了解决传统蚁群算法解决TSP问题时收敛速度慢、易陷入局部最优的问题,提出了一种名为FENA2O的改进蚁群算法。通过寻找并更新精英蚂蚁行走路径来提高收敛速度,通过规定蚂蚁数量来降低陷入局部最优的可能,配合2-Opt算法进一步优化所得路径。实验结果表明,算法改进后的收敛速度得到了较大提高,并能够有效解决局部最优。     

一种启发式动态信息素更新策略的蚁群算法

针对蚁群系统（ACS）在解决TSP问题上存在易陷入局部最优和收敛速度较慢的问题,提出了一种改进的启发式蚁群算法。在迭代前期赋予伪随机因子较小的阈值,从而使蚂蚁能以较大的概率选择轮盘赌方式完成解的构建,扩大了解的搜索范围;同时通过引入迭代最优蚂蚁进行全局信息素更新,来进一步增加了解的多样性,使算法避免陷入局部最优。在迭代后期随着伪随机因子参数值变化幅度的加快,则用至今最优蚂蚁来取代迭代最优蚂蚁,以促进搜索进程很快的向最优解附近收敛,加快了收敛的速度。实验仿真结果表明改进后的算法在前期能够有效地跳出局部最优,并且在后期能够明显提升收敛速度。     

改进型量子蚁群算法求解QoS单播路由

针对遗传以及蚁群算法在求解QoS单播路由问题时收敛速度慢和易于陷入局部最优的问题。采用量子蚁群算法求解QoS单播路由,采用量子旋转门实现蚂蚁的移动,用量子非门来实现蚂蚁位置的变异,同时为了确保算法不陷于局部最优,对量子蚁群算法做了改进,并进行了对比实验。实验表明该算法不但克服了遗传以及蚁群算法的易限于局部最优解的缺陷,在收敛速度上也优于相关算法,能较好地解决QoS单播路由问题。     

基于启发式机制的改进蚁群算法

针对蚁群算法在求解最短路径问题时收敛速度慢,容易陷入局部最优解的问题,提出基于启发式机制的改进蚁群算法.在蚁群系统（ant colony system,ACS）算法基础上通过候选节点到目标点的距离动态调整启发函数,提高收敛速度;算法陷入局部最优时,引入惩罚函数,使当前最优路径上的信息素快速下降而降低蚂蚁下一次搜索正反馈的影响,避免算法陷入局部最优.仿真实验表明,在复杂环境中,包括终点处存在凹形障碍物时,该算法在解的质量和收敛速度上都显示出了良好的性能.     

基于改进蚁群算法的机器人路径规划

为了解决蚁群算法易陷入局部最优及收敛速度慢等问题,研究提出一种改进的蚁群算法,通过改变方向因子的计算方式来减少寻优所需时间;通过改变信息素的更新方式避免陷入局部最优解。在栅格地图中进行仿真模拟实验,综合结果表明,改进算法与传统蚁群算法及其他相关算法相比,具有得到路径更短、收敛速度更快且路径拐点更少等优点。     

基于统计分析的自适应蚁群算法及应用

路径规划是机器人关键技术之一。利用改进的蚁群算法进行机器人的路径规划。针对传统蚁群算法收敛速度慢且易陷入局部最优解的缺陷,在Ant Colony System算法基础上,对每代蚁群动态随机统计分析,提取最优、平均和最差的蚂蚁信息,构成自适应算子用于局部信息素的自适应更新。仿真实验结果证明该自适应算子在平衡增加收敛速度和陷入局部最优解矛盾的问题中是有效的。     

基于自适应阈值蚁群算法的路径规划算法

为了克服传统蚁群算法容易陷入局部最优的问题,提高环境适应能力和收敛速度,提出了一种基于自适应阈值的蚁群算法．在优化过程早期,通过阈值对蚂蚁寻优过程进行干预避免其陷入局部最优解．随着迭代次数的增加,阈值对蚂蚁寻优过程的影响不断减小,直至完全由信息素和启发信息来指导蚂蚁寻优．仿真实验验证了优化算法的可行性和有效性．与现有蚁群算法进行比较,实验结果表明：在不同的环境下,文中提出的算法都能快速的规划出一条较优的路径,并且收敛速度和环境适应能力令人满意．     

基于邻域搜索的改进最大最小蚁群算法

针对蚁群算法求解旅行商问题时易陷入局部最优的问题,提出一个改进的混合最大最小蚁群算法,并应用于求解旅行商问题.上述算法设计了一种新的信息素更新模型,单个蚂蚁每走一步就进行信息素局部更新,在所有的蚂蚁搜索一周后,最优路径蚂蚁进行全局信息素更新.提出一种新的邻域搜索模型,将邻域大小设置为原来的一半,提高了计算的效率.在每个蚂蚁的一个周期循环后,使用邻域搜索算法优化最优解的路径长度.仿真结果表明,改进算法具有较高的求解精度和收敛速度.     

基于改进蚁群算法的三维路径规划

针对移动机器人在海水环境中的三维路径规划问题容易陷入局部最优和收敛慢等瑕疵，根据三维环境全局信息来改进蚁群算法以提高实时性和收敛速度。改进蚁群算法的启发函数，采用局部信息和全局信息结合动态地改进信息素更新方式，以及根据三维空间中路径的平坦程度和光滑度二阶微分分别增加了一阶微分和二阶微分来再次修改信息素更新规则。仿真对比实验结果显示改进后的蚁群算法克服了收敛速度慢、容易陷入局部最优的缺点。     

基于改进蚁群算法的机器人路径规划算法

针对机器人路径规划中,传统蚁群算法收敛速度慢、易陷入局部最优解等问题,提出了一种移动机器人路径规划的改进蚁群优化(ACO)算法。用栅格法建立环境模型,并基于人工势场建立启发信息素矩阵,降低了蚂蚁在初始阶段搜索的盲目性;引入激励函数,降低搜索过程中的死锁现象;改进信息素的更新机制,增强了优秀蚂蚁对全局路径规划的影响。仿真结果表明:改进后蚁群算法的机器人路径规划算法加快了收敛速度,具有较强的鲁棒性和全局寻优能力。     

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.