Electron density distributions and bonded interactions for the fibrous zeolites natrolite, mesolite and scolecite and related materials

 For the fibrous zeolites natrolite, Na₂[Al₂Si₃O₁₀]·2H₂O, mesolite, Na₂Ca₂[Al₂Si₃O₁₀]₃·8H₂O, and scolecite, Ca[Al₂Si₃O₁₀]·3H₂O, with topologically identical aluminosilicate framework structures, accurate single-crystal X-ray diffraction data have been analyzed by least-squares refinements using generalized scattering factor (GSF) models. The final agreement indices were R(F ) = 0.0061, 0.0165, and 0.0073, respectively. Ensuing calculations of static deformation [Δρ(r)], and total, [ρ(r)], model electron density distributions served to study chemical bonding, in particular by topological electron density analyses yielding bond critical point (bcp) properties and in situ cation electronegativities. The results for 32 SiO, 24 AlO, 14 CaO, and 12 NaO unique bonds are compiled and analyzed in terms of both mean values and correlations between bond lengths, bonded oxygen radii, bcp densities, curvatures at the bcps, and electronegativities. Comparison with recent literature data obtained from both experimental electron density studies on minerals and model calculations for geometry-optimized molecules shows that the majority of the present findings conforms well with chemical expectation and with the trends observed from molecular modeling. For the SiO bond, the shared interaction is indicated to increase with decreasing bond length, whereas the AlO bond is of distinctly more polar nature, as is the NaO bond compared to CaO. Also, the observed ranges of the Si and Al in situ electronegativities and their mean electronegativities agree well with both Pauling's values and model calculation results, and statistically significant correlations are obtained which are consistent with trends described for oxide and nitride molecules. Received: 10 May 1999 / Revised, accepted: 14 September 1999     

Seismic fragility of plasterboard partitions via in‐plane quasi‐static tests

The seismic damage of internal partitions may cause significant earthquake loss; this phenomenon is caused by (a) their tendency to exhibit damage for low demand levels and (b) the consequent loss of inventory and breakdown that their collapse can cause. Quasi‐static tests are performed on six 5‐m‐high plasterboard internal partitions, which represent typical partitions in industrial and commercial buildings in the European area. A steel test setup is designed to transfer the load, which is provided by the actuator, to the partition. The testing protocol provided by Federal Emergency Management Agency (FEMA) 461 is adopted for the quasi‐static tests. The typical failure mode of the specimens is the buckling of a steel stud, which involves the boards that are attached to the buckled stud. The buckling failure usually concentrates across the plasterboard horizontal joints. A frictional behavior is exhibited for low demand levels, whereas a pinched behavior is shown for moderate‐to‐high demand levels. The interstory drift ratios required to reach a given damage limit state are evaluated using a predefined damage scheme. Based on the experimental data, the fragility curves for three different damage states (DS1, DS2, and DS3) are estimated. The fragility curve yields median interstory drift ratio values of 0.28%, 0.81%, and 2.05% and logarithmic standard deviations of 0.39, 0.42, and 0.46 for DS1, DS2, and DS3, respectively. Copyright © 2015 John Wiley & Sons, Ltd.     

Extended model of topological relations between spatial objects in geographic information systems

This paper presents an extended model for describing topological relations between two sets (objects) in geographic information systems (GIS). First, based on the definition of the topological relations between two objects, we uncover a sequence of topological relations between two convex sets.Second, an extended model for topological relations between two sets is proposed based on the new definition. The topological relations between two convex sets are expressed as a sequence of 4 × 4 matrices, which are the topological properties of A^o ∩ B^o, A^o\B, B^o\A, ∂A ∩ ∂B. The model is also extended for handling the properties of the topological relations between two non-convex sets, where the factor of first fundamental group is added to A ∪ B to handle these complex relations.The results show that the number of topological relations between the two sets is not as simple as finite but infinite and can be approximated by a sequence of matrices.     

基于拓扑关系的等高线高程自动赋值方法

地面高程信息是地理信息的重要组成部分，主要通过对地图上的等高线进行数字化来获取。等高线的数字化包括获取其特征点平面坐标和高程值两个方面。本文讨论了闭合等高线之间的拓扑关系及其表示形成，给出了根据等高线的平面位置判定其拓扑关系的算法。在此基础上，提出并实现了一种自动获取闭合等高线高程值的方法。实验表示，本文所述方法是正确可行的。     

基于剖分的三维拓扑ER模型研究

本文首先分析评述了目前三维ＧＩＳ空间拓扑数据模型研究状况,指出了Ｍａｒｔｉｅｎ Ｍｏｌｅｎｎａｒ的３Ｄ ＦＤＳ．,Ｍｏｒａｋｏｔ Ｐｉｌｏｕｋ等人的基于四面体的三维矢量数据模型等的局限性。继而根据笔者在三维空间实体及其相互间拓扑关系形式化描述方面的研究结果,分析研究了三维空间实体点、线、面、体与构成这些空间实体的ｋ－单纯形（０≤ｋ≤３）之间的实体关系,给出了相应的实体－关系（ＥＲ）图,提出了一个顾     

地理信息系统基础信息库的生成

介绍地理信息系统基础信息库的形成，阐述了承担完成北海市地理信息系统基础信息信息库时所采用的软、硬件环境，基础信息库生成的工艺流程以及基础信息库生成过程中的质量控制。     

Computing the fuzzy topological relations of spatial objects based on induced fuzzy topology

For modeling the topological relations between spatial objects, the concepts of a bound on the intersection of the boundary and interior, and the boundary and exterior are defined in this paper based on the newly developed computational fuzzy topology. Furthermore, the qualitative measures for the intersections are specified based on the α‐cut induced fuzzy topology, which are (A_α∧?A)(x)<1?α and ((A^c)_α∧?A)(x)<1?α. In other words, the intersection of the interior and boundary or boundary and exterior are always bounded by 1?α, where α is a value of a level cutting. Specifically, the following areas are covered: (a) the homeomorphic invariants of the fuzzy topology; (b) a definition of the connectivity of the newly developed fuzzy topology; (c) a model of the fuzzy topological relations between simple fuzzy regions in GIS; and (d) the quantitative values of topological relations can be calculated.     

Topological relations between spherical spatial regions with holes

ABSTRACT

There is growing interest in globally modelling the entire planet. Although topological relations between spherical simple regions and topological relations between regions with holes in the plane have been investigated, few studies have focused on the topological relations between spherical spatial regions with holes. The 16-intersection model (16IM) is proposed to describe the topological relations between spatial regions with holes. A total of 25 negative conditions are proposed to eliminate the impossible topological relations between spherical spatial regions with holes. The results show that (1) 3 disjoint relations, 3 meet relations, 66 overlap relations, 7 cover relations, 3 contain relations, 1 equal relation, 7 coveredBy relations, 3 inside relations, 1 attach relation, 52 entwined relations, and 28 embrace relations can be distinguished by the 16IM and that (2) the formalisms of attach, entwined, and embrace relations between the spherical spatial regions without holes based on the 9IM and that between the spherical spatial regions with holes based on the simplified 16IM are different, whereas the formalisms of other types of relations between spherical spatial regions without holes based on the 9IM and that between the spherical spatial regions with holes based on a simplified 16IM are the same.     

基于欧拉数的地籍拓扑关系计算

地籍实体间的空间拓扑关系是地籍信息系统时空数据组织与查询、空间数据质量控制、空间数据更新处理等的基础,然而现有拓扑关系模型在计算地籍实体间的拓扑关系方面存在不足。本文提出了一种基于目标整体交/差和欧拉数的地籍实体拓扑关系计算方法,其将目标看作一个整体,用目标整体间∩(交)、\(差)两个集合操作的结果来区分目标之间的拓扑关系,结果的取值包括内容、维数和欧拉数三个拓扑不变量。研究工作表明本文所提出的拓扑关系模型克服了现有拓扑关系模型在描述地籍实体间拓扑关系方面存在的不足,并且其已成功地应用到地籍空间数据更新处理中。     

时空一体化数据的TGIS设计的初步探讨

在大量调研国外有关文献的基础上，对受到国际ＧＩＳ领域的高度重视的时空一体化数据的地理信息系统ＴＧＩＳ（ＴｅｍｐｏｒａｌＧｅｏｇｒａｐｈｙＩｎｆｏｒｍａｔｉｏｎＳｙｓｔｅｍ）的概念模式、数据模型与功能设计等问题进行了分析，认为建立在时空拓扑结构基础上，具有时空数据管理、查询、时间维数据整合和内插、时序及时空分析工具、可视化操作等功能的ＴＧＩＳ将是未来ＧＩＳ发展的趋势，它将极大地促进ＧＩＳ在应用领域的广度和深度。