A semidynamic construction of higher-order voronoi diagrams and its randomized analysis

Thek-Delaunay tree extends the Delaunay tree introduced in [1], and [2]. It is a hierarchical data structure that allows the semidynamic construction of the higher-order Voronoi diagrams of a finite set ofn points in any dimension. In this paper we prove that a randomized construction of thek-Delaunay tree, and thus of all the orderk Voronoi diagrams, can be done inO(n logn+k ³n) expected time and O(k²n) expected storage in the plane, which is asymptotically optimal for fixedk. Our algorithm extends tod-dimensional space with expected time complexityO(k ^(d+1)/2+1 n ^(d+1)/2) and space complexityO(k ^(d+1)/2 n ^(d+1)/2). The algorithm is simple and experimental results are given.This work has been supported in part by the ESPRIT Basic Research Action No. 3075 (ALCOM).     

改进的一对一支持向量机多分类算法

支持向量机的一对一多分类算法具有良好的性能,但该算法在分类时存在不可分区域,影响了该方法的应用.因此,提出一种一对一与基于紧密度判决相结合的多分类方法,使用一对一算法分类,采用基于紧密度决策解决不可分区,依据样本到类中心之间的距离和基于kNN (k nearest neighbor)的样本分布情况结合的方式构建判别函数来确定类别归属.使用UCI (university of California Irvine)数据集做测试,测试结果表明,该算法能有效地解决不可分区域问题,而且表现出比其它算法更好的性能.     

基于AOV图存储PLC梯形图的方法

提出一种直接以AOV(Activity On Vertex)图存储PLC(Programmable Logic Controller)梯形图的方法。编辑梯形图的同时,修改AOV图,然后根据AOV图的拓扑结构更新梯形图图符坐标,最后进行绘制显示。该方法无需进行梯形图向AOV图的转换,通过操作规则的约束来替代语法的检查,使梯形图的编辑更加便捷和规范。详细介绍了AOV图的编辑过程和坐标的更新算法。对AOV图向二叉树的转换算法进行修改,使其能适应于所有AOV图,并给出了相应的实例。     

企业产品质量管理系统

为解决企业产品质量管理工作中存在的问题,更高效、便捷的执行产品质量管理制度,介绍了一套企业产品质量管理的信息化实施方案。采用面向对象的分析和设计方法,运用统一建模语言中的常用概念和视图建模,重点描述使用用例图、类图和时序图的开发过程,最后使用基于B/S的结构实现该系统。     

全形态Voronoi图在地市级旅游区划中的应用研究

旅游区划是旅游规划的前期基本工作，其实质是按旅游资源的特性将其所在的空间进行分割，而分割所采用的依据就成为区划合理性与否的重要条件。由全形态Voronoi图的基本定义和旅游区划的内容可以看出，全形态Voronoi图最为适合这种地理客体的空间吸引范围的划分。最后以湖北省十堰市的旅游资源区划为全形态Voronoi图算例，说明了这种方式的实用性。     

Interplay Between Wetting and Phase Behavior in Binary Polymer Films and Wedges: Monte Carlo Simulations and Mean Field Calculations

Confining a binary mixture, one can profoundly alter its miscibility behavior. The qualitative features of miscibility in confined geometry are ratheruniversal and shared by polymer mixtures as well as small molecules, but the unmixing transition in the bulk and the wetting transition are typically well separated in polymer blends. The interplay between wetting and miscibility of a symmetric polymer mixture via large-scale Monte Carlo simulations in the framework of the bond fluctuation model and via numerical self–consistent field calculations is studied. The film surfaces interact with the monomers via short ranged potentials, and the wetting transition of the semi–infinite system is of first order. It can be accurately located in the simulations by measuring the surface and interface tensions and using Young’s equation. If both surfaces in a film attract the same component, capillary condensation occurs and the critical point is close to the critical point of the bulk. If surfaces attract different components, an interface localization/delocalization occurs which gives rise to phase diagrams with two critical points in the vicinity of the pre-wetting critical point of the semi–infinite system. The crossover between these two types of phase diagrams as a function of the surface field asymmetry is studied. The dependence of the phase diagram on the film thickness Δ for antisymmetric surface fields is investigated. Upon decreasing the film thickness, the two critical points approach the symmetry axis of the phase diagram, and below a certain thickness Δ_tri, there remains only a single critical point at the symmetric composition. This corresponds to a second-order interface localization/delocalization transition even though the wetting transition is of first order. At a specific film thickness, Δ_tri, tricritical behavior is found. The behavior of antisymmetric films is compared with the phase behavior in an antisymmetric double wedge. While the former is the analog of the wetting transition of a planar surface, the latter is related to the filling behavior of a single wedge. Evidence for a second-order interface localization/delocalization transition in an antisymmetric double wedge is presented, and its unconventional critical behavior is related to the predictions of Parry et al. (Phys. Rev. Lett. 83:5535 (1999)) for wedge filling. The critical behavior differs from the Ising universality class and is characterized by strong anisotropic fluctuations.Invited paper presented at the Fifteenth Symposium on Thermophysical Properties, June 022–27, 2003, Boulder, Colorado, U.S.A.     

横移计量法在经编织物设计及分析中的应用

如何快速有效地设计、分析出正确的垫纱运动图,提高经编产品设计、分析效率,是从业人员面临的一个难点.运用横移计量法解决该难点是一种有效的途径.     

统计过程控制在软件工程中的应用

统计过程控制已经在制造业取得了成功的应用，近年在软件工程方面的应用也不断上升。本文通过分析这些指标数据，找出软件过程中各个阶段的不确定因素，并采取适当措施来保证软件过程处于统计意义下的受控状态，从而达到保证软件质量、提高软件生产效率的目的。     

钢铁生产流程铁资源效率的分析

以钢铁生产流程铁流图为基础,分析了高炉-转炉流程、电炉流程和混合流程的铁资源效率.流程铁资源效率的大小取决于各工序的金属收得率,金属收得率愈高,流程铁资源效率愈高.讨论了电炉钢比对混合流程铁资源效率的影响,结果表明,电炉钢比愈高,混合流程铁资源效率愈高.在此基础上,以中、美、日3国钢铁工业为例分析了电炉钢比和铁资源效率的关系.