基于收敛粒子群算法的重载铁路列车运行调整方法

针对施工天窗对重载铁路行车安全限速和行车安全产生的不良影响,提出了基于收敛粒子群算法的重载铁路列车运行调整方法。首先,在分析列车追踪间隔影响因素的基础上,推导出不同编组类型重载列车之间的追踪间隔计算公式,实现了重载列车追踪间隔计算。然后,考虑施工天窗后的限速要求,以重载列车总晚点时间为优化目标,以列车区间最少运行时分、追踪间隔时分、列车停站时分、天窗时间段内禁止行车、天窗后安全限速等为约束条件,建立了施工条件下重载铁路列车运行调整模型,刻画了考虑安全限速的重载列车运行调整问题。通过优化列车到站、离站以及通过车站时刻,实现重载列车运行调整。进而,针对模型特点,在经典粒子群算法中引入收敛因子,设计了收敛粒子群算法对模型进行求解。最后,以朔黄铁路运输生产数据为基础,对建立的重载铁路运行调整模型进行实例化处理,验证了模型和算法。实验结果表明,对于求解重载铁路运行调整问题,设计的收敛粒子群算法比经典粒子群算法在计算效率上提升了5.45%,而求解精度保持不变。该方法可压缩重载列车追踪间隔,提高重载铁路运输效率,保证行车安全,提高基于安全限速的列车运行调整效率,为施工条件下重载铁路列车运行调整工作提...     

基于两阶段算法的列车调度问题

考虑突发铁路损坏对列车运行的影响,在列车运行调度理论的基础上,建立了单线铁路调度模型,设计了一种带有突发事件处理能力的两阶段列车调度算法,第1阶段对列车区间运行速度进行调整,第2阶段对列车的停站时间进行调整.将3种有效的搜索算子、一种自适应更新规则与粒子群算法相结合,以列车延迟率作为优化目标,求解单线铁路列车调度问题.通过将所提算法与其他算法在相同实验条件下进行测试对比,并进行突发事件测试,验证了所提算法的有效性.     

基于闭塞区间的高速列车运行时间与节能协同优化方法

提出了一种高速列车运行时间与节能协同优化方法. 针对由动态调度层、优化控制层、跟踪控制层组成的列车运行控制与动态调度一体化结构, 设计了面向动态调度层和优化控制层的列车运行时间调整策略和节能速度位置曲线. 基于高速铁路闭塞区间, 建立了列车 − 区间模型和列车速度曲线节能优化模型. 利用模型预测控制方法对列车区间运行时间进行调整, 优化列车总延误时间; 根据调整后的区间运行时间设计列车运行优化速度位置曲线, 减少列车运行能耗. 仿真算例验证了设计的运行时间与节能协同优化策略的有效性.     

基于蚁群优化算法的高速列车运行调整研究

高速列车在运行过程中不可避免地会受到各种各样因素的影响,导致大量的高速列车出现晚点状况,影响高速列车的运行效率。为了保证所有的高速列车能够按照正点运行,对蚁群算法进行改进,引入混沌序列,优化蚂蚁的选路策略,建立以加权后列车总晚点时间最少为目标的高速列车运行调整模型,并且按照相应的约束条件对高速列车运行调整模型进行求解,实现对晚点高速列车运行图的快速调整。最后,通过比较算例得出,该算法能够有效解决高速列车运行调整问题。     

离散萤火虫算法在高速列车运行调整中的应用

列车运行调整是一类特殊的NP完全问题,由于约束众多,搜索空间庞大,可行解范围狭小,因此难以获得最优解。针对高速列车运行调整问题的特点,以智能算法中有代表性发展优势的萤火虫算法（FA）为基础,根据实际问题提出一种离散的萤火虫算法（DFA）进行求解。为了增加萤火虫群的多样性,避免算法陷入局部最优解,采用了基于变邻域搜索算法的扰动机制。将该算法用于高速列车运行调整问题,经过算例对比分析,基于离散萤火虫算法调整方案的计算结果优于普通启发式算法调整结果。     

基于仿真列车运行的时刻图编制方法

为了实现城市轨道交通的高效运输,在研究了城市轨道交通与铁路交通的差别后,提出了适用于城市轨道交通,基于仿真的列车运行时刻图编制方法.通过仿真列车在交通线路上的运行情况,将仿真结果作为运行时刻图,能按不同的时间区段来调整运行时刻图,以满足城市交通的运能需求与节能需求.在真实生产中取得了良好的经济效益.     

列车自适应交互多模型H∞滤波定位算法

针对在列车运行的复杂工况下噪声特性难以准确获知和状态模型与实际运行不匹配的问题,提出了列车自适应交互多模型H∞滤波算法.首先,依据列车运动状态自适应调整系统状态噪声特性和模型.其次,通过自适应补偿误差协方差增强H∞滤波的鲁棒性.最后,以哈尔滨到大庆的部分实测数据对算法的有效性进行了仿真验证.结果表明:所提算法具有自适应...     

单线列车调度问题的双向阻塞车间调度模型及其粒子群求解算法

针对单线列车调度问题的特点,以线路中列车的总运行时间最小为目标,建立了可以直观描述问题解空间的双向阻塞车间调度模型,并提出了一种有效的离散粒子群优化算法进行求解。该算法基于双向阻塞车间调度模型设计了排列编码形式,从而可确定列车的运行顺序,同时利用随机策略和运行时间最短优先策略选择列车运行轨道;算法在求解过程中,提出了列车冲突的检测和化解方法,并按照“调度-检测冲突-化解冲突”的步骤逐区段调度列车运行;最后,利用离散粒子群优化算法进行全局优化,得到问题的最优解。仿真实例表明,所得模型和算法能够高效地求解单线列车调度问题。     

轨道交通列车追踪运行模型及追踪间隔研究

轨道交通列车追踪间隔是制定及调整列车运行计划的基础,构建精确的列车追踪运行模型是研究列车追踪间隔的关键。根据列车追踪运行规律建立城市轨道交通CBTC列车追踪运行模型,采用Matlab编制程序对CBTC列车追踪运行进行仿真,设计快速迭代算法对列车追踪间隔进行求解。仿真所得列车运行曲线及相关数据与列车实际追踪运行情况一致,求解所得列车追踪间隔值与现场实际测量值一致,充分验证了模型的可用性及仿真精度。CBTC列车追踪运行模型及追踪间隔快速迭代算法可用于列车追踪运行方面的研究,为城市轨道交通运输组织优化与管理提供了理论依据。     

基于自适应遗传算法的城际列车运行图编制方法

对城际列车运行图编制问题进行研究,确定列车在各区间运行的最优顺序,并建立以列车总运行时间最小为目标的列车运行图优化模型。在此基础上,采用自适应选择机制的变异算子和交叉算子,设计一种自适应遗传算法进行求解。该算法采用“列车-区间运行顺序”的染色体二维编码形式,首先对列车在各区间运行的顺序进行编码;求解过程中,结合广度优先循环布线的原则进行解码,通过“到发时刻-发现冲突-解决冲突”逐区段进行铺画,得到列车在各车站实际的到发时刻;同时,利用自适应遗传算法进行全局优化,得到问题最优解。实验表明,自适应机制能够提高算法性能并较快得到列车最优运行顺序,铺画出更高效准确的列车运行图。     

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.