Qualitative representation of spatial knowledge in two-dimensional space

Various relation-based systems, concerned with the qualitative representation and processing of spatial knowledge, have been developed in numerous application domains. In this article, we identify the common concepts underlying qualitative spatial knowledge representation, we compare the representational properties of the different systems, and we outline the computational tasks involved in relation-based spatial information processing. We also describesymbolic spatial indexes, relation-based structures that combine several ideas in spatial knowledge representation. A symbolic spatial index is an array that preserves only a set of spatial relations among distinct objects in an image, called the modeling space; the index array discards information, such as shape and size of objects, and irrelevant spatial relations. The construction of a symbolic spatial index from an input image can be thought of as a transformation that keeps only a set of representative points needed to define the relations of the modeling space. By keeping the relative arrangements of the representative points in symbolic spatial indexes and discarding all other points, we maintain enough information to answer queries regarding the spatial relations of the modeling space without the need to access the initial image or an object database. Symbolic spatial indexes can be used to solve problems involving route planning, composition of spatial relations, and update operations.     

海底管道系统失效故障树的建立及定性分析

受自然环境、管道腐蚀、第三方破坏及管理不善等因素的影响,海底管道系统在铺设及运行过程中常常会失效。文中以海底管道穿孔、凝管、断裂和设备故障等主要失效形式为顶事件建立了海底管道系统失效故障树,通过系统的定性分析得到了海底管道系统失效故障树的37个一阶最小割集,进而确定了影响海底管道系统失效的4项主要因素,并针对这些主要因素提出了相应的解决问题的措施。     

Markov analysis of qualitative dynamics1

Common sense sometimes predicts events to be likely or unlikely rather than merely possible. We extend methods of qualitative reasoning to predict the relative likelihoods of possible qualitative behaviors by viewing the dynamics of a system as a Markov chain over its transition graph. This involves adding qualitative or quantitative estimates of transition probabilities to each of the transitions and applying the standard theory of Markov chains to distinguish persistent states from transient states and to calculate recurrence times, settling times, and probabilities for ending up in each state. Much of the analysis depends solely on qualitative estimates of transition probabilities, which follow directly from theoretical considerations and which lead to qualitative predictions about entire classes of systems. Quantitative estimates for specific systems are derived empirically and lead to qualitative and quantitative conclusions, most of which are insensitive to small perturbations in the estimated transition probabilities. The algorithms are straightforward and efficient.     

The Design of Discrimination Experiments

Experimentation plays a fundamental role in scientific discovery. Scientists experiment to gather data, investigate phenomena, measure quantities, and test theories. In this article, we address the problem of designing experiments to discriminate between two completing theories. Given an initial situation for which the two theories make the same prediction, the experiment design problem is to determine how to modify the situation such that the two theories make different predictions for the modified situation. The modified situation is called a discrimination experiment. We present a knowledge-intensive method called DEED for designing discrimination experiments. The method analyzes the differences in the two theories' explanations of the prediction for the initial situation. Based on this analysis, it determines modifications to the initial situation that will result in a discrimination experiment. We illustrate the method with the design of experiments to discriminate between several pairs of qualitative theories in the fluids domain.     

TBM地区低孔渗高产气储层预测

 本文从TBM地区目的层的地质和地球物理特征分析出发，以三维地震资料为基础，综合利用人工和神经网络波形分类等定性储层预测方法和利用反演及敏感地震属性分析，对TBM地区低孔渗砂岩分布区开展了砂体展布特征分析和天然气高产区预测研究。根据研究结果部署了10口钻井，已完钻的4口井中有3口获得高产气流（其中DK27井日产天然气36.8×10⁴m³）。值得指出的是，目前所用的预测方法还不能预测厚度小于6m的单砂层或砂层组构成的储层。     

Provision of accuracy for quantitative determination of small amounts of components: Principles of resolving the problem and their realization

Versions are suggested for resolving the problem of monitoring the accuracy of determining small amounts of components in samples of substances and materials. __________ Translated from Izmeritel'naya Tekhnika, No. 1, pp. 52–57, January, 2006.     

Evaluating Community Safety Programmes and Community Engagement: The Role of Qualitative Methods and Collaborative Approaches to Policy Research

This article explores the role of qualitative and collaborative methods when undertaking evaluation research into local community safety partnerships and neighbourhood strategies. It draws on recent examples of research and evaluation studies of regeneration and community safety programmes in a number of cities and towns in England. The discussion is set against the background of the major changes in policy relating to crime and community safety, particularly the introduction of Crime and Disorder Partnerships and their engagement with local communities. The value of qualitative methods in exploring some key questions is discussed, particularly within a collaborative approach to policy research.     

膨胀弯管在管道柔性设计中的定性分析

为防止管道因热胀冷缩、管道支撑或端点附加位移造成的应力问题,对管线中设置的膨胀弯管进行定性分析.通过2个参数的变化对膨胀弯管进行编号得到多种设计方案,用ANSYS建立管道的有限元模型,并分析各方案中膨胀管道的变形、应力和弯矩等;根据分析结果对膨胀弯管设计半径、设置位置和形状进行定性分析.该定性分析结果可为膨胀弯管概念设计和管道柔性设计提供参考.     

云关系模式及其应用*

在云变换的基础上,结合非经典关系数据库理论提出了云关系模式,给出了云关系模式的定义,探讨了云关系模式的意义,并将它应用于学生成绩数据库中,改进了目前学生定性评定方法,克服了其中的主观因素,实例证明该方法具有可行性.     

对环氧丁烷异构体定性分析的探讨

通过用标样、GC／MS、利用化合物的沸点规律和I值增量等方法，对环氧丁烷异构体进行全面的定性分析。同时在鲨鱼烷毛细管柱上分别于3个柱温下，测出了各组分的Kovats保留指数，找出了各组分保留指数与柱温的规律。