时空相关的混载校车路径问题邻域搜索

为节约混载校车路径问题求解过程中邻域解搜索的时间,引入时空距离和时空相关度概念,将邻域搜索空间限定在合理的范围内.该算法首先计算站点间的时空距离,再附加上简单约束的预判断,从而得到时空相关度矩阵.然后对于任意学生乘车站点,将其他可能与之直接相连的站点按照时空相关度排序,形成一个邻接列表.在邻域搜索过程中,通过限定邻接列表长度,仅尝试最终接受概率较大的一部分移动操作,以此缩小邻域搜索空间,从而提高算法效率.在国际标准案例上的测试结果表明,基于时空相关度的搜索策略能在基本不降低求解质量的情况下,平均节省50％以上的求解时间.     

校车路径问题的改进迭代局部搜索算法

针对考虑站点服务时间、学生最大乘车时间约束的校车路径问题(SBRP),提出一种改进迭代局部搜索(ILS)算法以提升求解质量。该算法使用大规模邻域搜索(LNS)算法作为扰动算子;在解的破坏过程中,设计一组解的破坏因子并赋以一定的选择概率,每隔若干次迭代后根据解的质量自适应更改破坏因子的选择概率,进而调整解的破坏程度。为提升ILS解的多样性,算法采用了基于偏差系数的邻域解接受准则。在国际基准测试案例上进行了测试,测试结果表明在ILS算法中使用自适应调整破坏程度的LNS扰动比常规扰动和其他破坏扰动的求解质量有大幅提升;与蚁群算法的比较结果进一步验证了改进算法的有效性。     

基于局部视觉感知及语义联想的图像理解模型

对一个区域内多所学校进行校车路径规划时,允许校车混载不同学校的学生能显著地减少校车数量,从而降低运营成本。已有学者针对允许混载的校车路径问题(SBRP)提出了启发式算法,但这些算法对邻域解的搜索不够全面,在缩减路径方面仍有较大的提升空间。提出了一种以记录更新法(record-to-record travel,RRT)为基础的启发式算法。该算法从初始解出发,利用求解有时间窗装卸问题(PDPTW)时使用的算子搜索邻域解,逐步优化校车路径数目。与现有算法相比,该算法扩展了求解混载SBRP的启发策略,能够在全局范围内对校车路径进行优化,从而获得所需校车较少的路径规划方案。实验结果验证了该算法的有效性。     

车辆数限制的多车型校车路径问题模型及算法研究

为适应校车路径规划中校车有多种车型且每种车型数量受限的需求,建立车辆数限制的多车型校车路径问题(HFSBRP)的数学模型,并提出一种迭代局部搜索算法进行求解。该算法借助邻域随机选择的变邻域下降搜索(VND)算法完成局部提升。局部提升过程中,首先调整车型,然后再混合使用缩减路径数和提高车辆利用率的邻域解接受策略以提高算法的寻优能力,为保证解的多样性,允许接受一定偏差范围内的邻域解。此外,为避免算法过早陷入局部最优,设计了多点交换和移动的扰动规则。基于国际基准测试案例进行模型验证和算法测试,实验结果表明了模型的正确性和算法的有效性。     

一种求解多校多车型校车路径问题的元启发算法

针对多种车型可用的多校校车路径问题(SBRP),建立数学模型,并提出了一种迭代局部搜索(ILS)元启发算法进行求解。该算法引入并改进了带时间窗的装卸一体化问题(PDPTW)求解中的点对邻域算子,并使用可变邻域下降搜索(VND)完成局部提升。局部提升过程中,设计一种基于路径段的车型调整策略,尽可能地调整车型,降低成本,并允许接受一定偏差范围内的邻域解以保证搜索的多样性。对于局部提升得到的最好解,使用多点移动方法对其进行扰动,以避免算法过早陷入局部最优。在国际基准测试案例上分别测试多校混载和不混载模式下算法的性能,实验结果验证了设计算法的有效性。进一步使用提出的算法求解单车型多校SBRP问题,并与后启发算法、模拟退火算法和记录更新法等算法进行比较,实验结果表明该算法仍然能够获得较好的优化效果。     

求解多车型校车路径问题的带参数选择机制的GRASP算法

考虑到校车路径安排过程中不同车型容量和成本的差异,建立了多车型校车路径问题(SBRP)模型,并提出了一种带参数选择机制的贪婪随机自适应(GRASP)算法进行求解。在初始解构造阶段,设计一组阈值参数控制受限候选列表(RCL)的大小,使用轮盘赌法选择阈值参数。完成初始解构造后,使用可变邻域搜索(VNS)进行邻域解改进,并记录所选择的参数和解的目标值。算法迭代过程中,先设置相同阈值参数的选择概率,每隔若干次迭代后,评估每个阈值参数的性能并修改其选择概率,使得算法能够得到更好的平均解。使用基准测试案例进行了测试,比较了基本GRASP算法与设计的GRASP算法的性能,并与现有求解多车型校车路径问题的算法进行对比,实验结果表明所设计的算法是有效的。     

求解多车型校车路径问题的混合集合划分的GRASP算法

针对不同规划场景下具有不同优化目标的多车型校车路径问题(HSBRP),提出一种混合集合划分(SP)的贪婪随机自适应(Greedy Randomized Adaptive Search Procedure,GRASP)算法。根据GRASP算法寻优过程中产生的路径信息构建SP模型,然后使用CPLEX精确优化器对SP模型进行求解。为了适应不同类型的HSBRP问题,改进GRASP的初始解构造函数得到一个可行解,并将其对应的路径放入路径池;在局部搜索过程中应用多种邻域结构和可变邻域下降(VND)来提升解的质量,同时在路径池中记录在搜索过程中得到提升的路径和在每次迭代中得到局部最好解的路径信息。使用基准测试案例进行测试,实验结果表明在GRASP算法中,混合SP能够有效地提高算法的求解性能和稳定性,并且该算法能适应不同优化目标下车型混合和车辆数限制两类HSBRP的求解;与现有算法的比较结果再次验证了所提算法的有效性。     

混合粒子群算法求解带软时间窗的VRPSPD问题

针对带软时间窗的同时集配货车辆路径问题（VRPSPD）,建立了以车辆派遣成本、行驶成本和时间窗惩罚成本之和最小为目标的车辆路径优化模型;设计混合粒子群算法进行求解,该算法结合以变邻域下降搜索为主体的适应性扰动机制,采用适应性选择邻域策略,并在每个邻域搜索中应用可变的循环次数,以此提高对解空间的探测能力和搜索效率。数值实验结果表明了该算法的可行性和有效性。     

同时送取货选址路径问题及混合免疫算法

研究了同时送取货的选址路径问题(location-routing problem with simultaneous pickup and delivery,LRP-SPD),在同时送取货问题中,每个客户都有送货需求和取货需求,并且两种需求需要同时进行服务.在此条件下,建立了以仓库的选址成本、车辆启用成本及运输成本等目标和最小的选址路径模型;针对该模型的特点,设计改进了一种混合免疫优化算法(hybrid immune algorithm,HIA)对该问题进行求解,运用贪心聚类算法生成初始解,利用原始免疫算法对抗体进行评价排序,由邻域搜索操作改进原始算法的免疫操作.最后,通过使用混合免疫优化算法与原始免疫优化算法、模拟退火算法、蚁群算法分别对案例进行求解和对比分析,验证了提出模型的可行性和算法的有效性.     

需求可拆分的汽车零部件循环取货路径优化研究

为了降低汽车零部件入厂物流的总成本,针对汽车零部件入厂物流的循环取货路径规划问题,提出将供应商集货需求拆分配送的改进数学模型,以最小化运输和库存总成本为目标函数,并且满足时间窗和车辆容量的限制。通过设计禁忌搜索算法求解,并根据模型的特点对初始解及邻域搜索方法进行改进。最后应用实验数据验证算法有效性,并与其他算法对比,结果表明通过需求拆分可以节约运输成本并提高车辆装载率。     

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。     

基于QTE的蒙古文显示机制研究与实现

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。