气候概率分布理论的新内涵及其展望

近年来,国内外学者关于气候概率分布理论和应用的研究已经取得了许多新的成果,本文简要回顾近年来这一领域已经发展起来的新内涵,并提出未来可能的研究设想。     

广义大气密度函数

把大气密度函数的定义从几何空间扩大到相空间(如压力温度等),引入了广义大气密度函数概念,讨论了这个函数的计算方法和积分特点,给出了两个简单的广义大气密度函数实例,还讨论了相空间中的大气方程组问题。     

扩展空间句法在城市土地定级中的应用

研究了城市道路结构和城市土地定级之间的关系,介绍了空间句法及其扩展理论,实现了其在地理信息系统环境中在城市土地定级中的应用。     

城市基础空间数据基准的统一和更新

对城市基础地理信息数据库的数据源——空间位置数据的基准统一和更新方法进行了探讨,提出七参数转换和平面相似变换是实现空间位置数据的基准统一和更新的实用方法,并通过算例证明了该方法的正确性。     

关于计算空间曲线预应力筋张拉伸长值的探讨

把肇源松花江大桥划分成57个受力段,利用“桥梁博士V2．8”系统进行计算,采用简化法计算了曲线预应力筋张拉伸长值、张拉控制应力和张拉控制力。     

引力波、引力波源和引力波探测实验

引力波是爱因斯坦和其他物理学家提出的关于广义相对论的四大预言之一。除了PSR1 91 3 + 1 6引力辐射阻尼的观测提供了引力波存在的间接证据外 ,科学家至今仍没有在实验室中确证引力波的存在。由于人类目前的技术水平还不可能在实验室中产生强度可供探测的引力波 ,而宇宙中存在大量大质量、高速运动的天体 ,有可能产生较强的引力波 ,天体引力波源自然成为现阶段科学家研究引力波的首选。本文介绍广义相对论框架下预言的引力波性质 ,引力波探测的理论依据 ,共振型棒式天线和激光干涉仪两大类探测器的基本原理 ,引力波探测实验的现状和面临的困难 ,科学家采取的对策 ,以及爆发型和连续型两类天体引力波源。最后介绍了正在计划中的几个引力波探测空间实验     

Spatial gradient analysis of urban green spaces combined with landscape metrics in Jinan City of China

1IN T R O D U C T IO NUrban green spaces can be consideredas the outdoorplacesintheurban covered with significanatmounts ofvegetation,naturalor manmade,as opposed to areasthatare paved or having buildingon them(JIM andC HEN,2003;SHIVANAND and SUZANA,2005)…     

Fractal Approach,Analysis of Images and Diagenesis in Pore Space Evaluation

Simple net model constructed by authors, facies analysis and compaction models, were applied to evaluate reservoir properties of sandstone facies of the Carpathian Flysch (the Istebna sandstones). The applied net model was built on the base of fractal approach proposed by Don Turcotte in 1977 and computer analysis of images. Laboratory measurements include porosity, density, permeability to nitrogen, mercury injection capillary pressure tests, and microscopic analysis of thin sections. D.W. Houseknecht's theory, proposed in 1987, was applied for compaction and cementation modeling. The residual saturation data were used to validate obtained results. Net model allows an evaluation of filtration properties of analyzed sandstones and to distinguish the classes of similarity of pore space. The extracted parameters of classes of similarity were correlated with facies scheme of the investigated geological structure. Influence of compaction and cementation on pore space parameters was discussed.     

The Terrain Correction in a Moving Tangent Space

Conventionally the terrain/topographic reduction is based on the Bouguer Plate, which is flat and extends in the local tangent plane/horizontal plane to infinity. Here we aim at an error estimate of such a planar approximation of the Newton integral of the type of a disturbing potential and gravitational disturbance as linearized forms of the gravitational potential and the modulus of gravitational field intensity. To effect this quality control of the conventional terrain reduction, we first transform the spherical Newton functional from an equatorial frame of reference to an oblique meta-equatorial frame of reference with the evaluation point as a meta-North pole, and then by means of an oblique equiareal map projection of the azimuthal type to a tangent plane which moves at the evaluation point. The first term of these transformed Newton functionals is the planar approximation. The difference between the exact Newton kernels and their planar approximation are plotted and tabulated in Tables 1-3. Three configurations are studied in detail: for points at radius r = 10 km around the evaluation point the systematic error varies from 0.26% for a spherical height difference of the order of H – H* = 5 km, more than 0.80% for a spherical height difference of the order of H – H* = 1 km, and more than 1.60% for a spherical height difference of H – H* = 500 m. In contrast, the systematic error for spherical height difference H – H* = 1 km at a distance of r = 1000 km from the evaluation point increases to 44%. Indeed, the newly derived exact Newton kernels which are of the convolution type and are represented in the tangent space moving with the evaluation point can be preferably used with little extra computational effort.     

新世纪湖北省城镇空间发展战略及对策

21世纪湖北省城镇空间发展研究是以空间相互作用理论为基础,提出了湖北省城镇空间发展的“一点二线,占轴开发;实内拓外,圈层扩展;多重循环,交叉推进”的模式,其依据主要是：①从区位理论看,湖北省武汉市地处中国中部,理所当然地承担着承东启西、南北交流的枢纽作用,武汉就是湖北省乃至长江中游的极核城市;②从经济区位来看,“两线”交汇于湖北省的经济增长极核－武汉,“两线”地带集中湖北省的大部分工业、农业、人口和城市;③湖北省盆状地形,向心状的水系,向心状的土地利用以及向心交汇的综合运轴网络,构成了以武汉为中心的集聚与扩散的层状网络结构;在此基础上构想今后一段时间内湖北省城镇空间组织的格局及建设层次,即武汉（一级）－襄樊、荆州、宜昌、黄石（二级）－十堰、荆门、鄂州、随州、恩施、仙桃、枝城等（三级）。