基于综合信息元的多源数据集成

基于地理信息系统的空间分析模型一般采用传统空间叠加方法进行数据集成,这一方法在具体操作过程中叠加产生的单元在大小和数目上具有很大的不确定性,同时还会产生大量无意义的细小图斑,影响空间分析模型的有效实施．本文引入综合信息元作为地理信息系统空间数据采集、存储、管理以及空间分析模型的基本单元,它在一定研究目的和空间尺度下具有相对稳定的大小、均一的内部属性和清晰的边界．针对不同的相关因子以及数据类型,综合信息元可以采用数据叠加法、综合法和网格划分法等进行构建．一旦综合信息元得以确定,便可以此为基础,进行多源数据的集成,为空间分析模型的实施提供数据准备．本文进一步探讨了ARC／INFO环境下基于综合信息元的多源数据集成方法及其程序实现．结果表明,这一集成方法在精度满足分析要求的同时,集成效率大大提高,同时与传统数据叠加方法相比,不但单元数目明显减少,而且单元边界相对固定,可以避免传统数据叠加方法因多次叠加操作而增减图元数目以及由于大量无意义细小图斑产生而带来的误差．     

空间有限元网格自动划分的方法

本文介绍了利用计算机编程，对空间有限元计算所需网格进行划分的一种方法，并给出了有关计算公式，从而为空间有限元计算提供了网格、节点和单元的信息．作者使用该方法对内燃机某些零件进行了有限元网格划分，结果表明该方法简单可行．     

约束方程的分区网格划分法

在有限元中．把形状复杂的模型划分成四边形或六面体网格，一直以来都是一个很难解决的问题．利用约束方程进行分区网格划分，把一个模型分成多个形状规则的小区域并对其进行映像网格划分，然后使用约束方程，把相邻区域相接面上的单元节点联系起来．解决对复杂模型进行网格划分时很难划分出理想网格的同腰．并对不同的小区域进行网格密度控制．     

改进的混合界面动态子结构法及其在车身结构动力分析中的应用

本文针对现行的混合界面动态子结构法进行改进，提高了模态综合效率和和精度．将改进的方法运用到承载式车身结构（ＳＶＷ７１８１）动力分析中，采用空间梁单元和板壳单元进行车身结构有限元建模，对车身结构进行了子结构划分计算．计算结果表明，该法计算量小，综合效率高，避免了以往方法计算量大、精度不够高、对计算机内存要求高的缺陷．而且为该型车的动态性能评估和进一步研究定型提供了理论计算依据，表明该方法具有实用推广价值和应用前景．     

基于多点约束的多尺度混合试验界面连接方法与验证试验

针对现有计算单元难以精确模拟结构局部复杂力学特性的问题,提出一种集成试验单元的多尺度混合模型构建方法.在不损失界面自由度的前提下,利用多点约束法实现了ABAQUS多尺度壳单元和实体单元分别与单柱试验单元的界面连接;基于Open Fresco平台,以底层中柱为试验单元进行了两层两跨平面钢框架的多尺度抗震混合试验,与有限元对比分析表明:多点约束法能够有效地实现不同尺度单元间的边界变形协调;试验单元能够真实直接地模拟结构重要部位的受力特性;在满足工程应用精度的前提下多尺度混合模型能够节约计算资源和时间,为改进结构抗震分析可靠性提供了新的研究手段.     

基于2.5维有限元算法的边界处理及网格划分

由于2.5维周期化技术能有效地处理列车振动波传播模拟过程中计算尺度与计算时间的矛盾,因而国内外学者在此理论基础上将FE(有限元)和粘滞边界以及IFE(无限元)等边界处理方法进行耦合.为讨论上述算法中有限元网格划分区域及单元大小对计算精度影响,通过运用软件Matlab编制程序读取Ansys中的模型信息,并将2.5维有限元和无限元边界耦合等算法在其中得以实现.在此基础上发现在相同的网格划分条件下,采用2.5维无限元边界较粘滞阻尼边界具有更高的精度,同时通过选取不同尺寸的有限元模拟区域及最大网格大小,将计算结果与经典解析解进行比较,并对上述网格划分参数的合理选择提出了建议.     

基于MSG理论的超薄梁弯曲问题的数值模拟

为了解决超薄梁弯曲计算中存在的低阶单元出现自锁和过刚的缺陷问题,采用基于应变梯度理论的假设应变有限元方法,研究了微尺度梁弯曲问题中的尺度效应.在假设应变单元设计中,非局部的应变梯度项通过围绕高斯点的胞元进行数值积分而得到.进一步在本构方程中引入等效应变梯度项,在积分本构方程时就可以反映材料在微细变形时的尺寸效应.首先,构造了一个基于细观机制的应变梯度理论的增强假设应变有限元模型.通过这种方法,非局部的应变梯度通过围绕高斯点的胞元积分而加入到本构方程中.由这个模型,发展了一个增强假设应变有限元程序,利用此程序对一超薄梁受均布荷载作用下,不同厚度,不同网格划分时的弯曲问题进行了数值模拟.结果显示,这种方法能够很好的体现出超薄梁在不同厚度和不同网格划分下的尺度效应.此方法具有较好的适用性.     

基于区域划分的空间信息交换研究

空间信息栅格网络环境下,信息交换过程中受到卫星不断运动、通信时延大的限制,提出了一个基于动态区域划分的信息交换模型,实现空间资源的共享及交换.     

地理元胞自动机研究综述

从地理元胞自动机的应用范围、地理元胞自动机转换规则的获取、地理元胞自动机空间划分、元胞自动机与GIS的集成等方面回顾了地理元胞自动机模型的研究,对地理元胞自动机模型研究的发展趋势进行了分析,认为地理元胞自动机模型研究在以下几个方面需要进一步深入：（1）应用范围应进一步扩大;（2）在确定地理元胞自动机的转换规则时应综合考虑自然因素和社会经济因素;（3）应加强地理元胞自动机与多智能体系统的集成研究;（4）应加强对地理元胞自动机的尺度划分及尺度效应的研究;（5）应进一步深化地理元胞自动机与GIS的集成研究。     

闽东南沿海城市热环境综合信息图谱的研究

以闽东南沿海城市热环境为研究对象,综合考虑影响热环境的自然和人文因素,尝试建立城市热环境的综合评价模型,并利用该模型对阂东南沿海城市2001年和2007年热环境质量进行了像元尺度的评价,同时引入地学信息图谱和分析方法,构建城市热环境综合信息图谱,用于揭示闽东南沿海地区城市热环境的动态演化规律,形成对区域尺度上城市热环境深层次的认识．     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.     

Tracking data management using topology of moving object database system for moving object constrained trajectory in LBS application

Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.