面向对象空间数据组织与管理的初步实现     

周东  张翔  夏小强  王前卫  罗小龙  刘少华 《测绘与空间地理信息》2007,30(6):117-118

通过分析3种传统数据模型的特点,得出它们在管理地理复杂对象方面的局限性,从而引出了面向对象数据模型。本文利用面向对象数据模型中的各种操作,以基本地理对象为基础构建复杂地理对象,并且在VC 6.0平台上实现了面向对象几何数据模型。  相似文献   

江汉平原粮食产量空间格局分析   总被引：1，自引：0，他引：1  

余晓敏  李强  张娜 《测绘地理信息》2020,(2):41-44,126

基于湖北省第一次地理国情普查数据、基础地理信息数据和统计年鉴等资料,采用洛伦兹曲线、Moran指数等对江汉平原典型4个粮食主产区监利县、洪湖市、仙桃市、潜江市的粮食产量空间格局进行了分析和研究。研究表明:①洪湖市耕地资源与粮食产量间的对应关系较为平等,粮食单产稳定,粮食生产空间聚集显著;②监利县、潜江市与仙桃市的耕地、粮食产量表现出极弱空间相关性或无相关性,粮食生产能力相对较差,耕地资源及产量未表现出空间聚集优势。该结论可为农业部门制定农业生产计划和发展规划提供良好的数据支撑,为地理国情普查成果的应用提供借鉴。  相似文献   

大兴安岭南段晚中生代侵入岩时空分布及主脊与东坡岩体特征对比     

王迪  赵国春  苏尚国  李宏星 《现代地质》2020,34(3):466-482

通过岩相学、地球化学、锆石U-Pb年代学对位于大兴安岭主脊上的马勒根坝岩体、朝阳沟岩体和大兴安岭东坡区域的野猪沟岩体、布敦化岩体的4个不同花岗岩岩体的岩石类型、主量和微量元素特征、年代学及构造背景进行对比分析,讨论了研究区在晚侏罗世—早白垩世的岩浆活动及地质背景。LA-ICP-MS锆石U-Pb年龄显示:主脊朝阳沟岩体和东坡布敦化岩体年龄分别为(154±1) Ma和(154.1±1.6) Ma,属于晚侏罗世岩体,主脊马勒根坝岩体和东坡野猪沟岩体年龄分别为(144.62±0.74) Ma和(140.2±2.7) Ma,属于早白垩世岩体。岩相学和地球化学特征显示:主脊岩体为高钾钙碱性-准铝质-过铝质花岗岩岩体,东坡岩体为钙碱性-高钾钙碱性-准铝质-弱过铝质TTG型岩体;主脊比东坡岩体更加亏损Ba、Nb、Sr、P、Ti、Eu元素,为高分异I型花岗岩,东坡岩体为正常的I型花岗岩。结合区域地质资料分析,认为在晚侏罗世—早白垩世伊泽奈崎板块NNW向俯冲和蒙古—鄂霍次克洋闭合共同作用于大兴安岭南段地区,在大兴安岭主脊形成断裂带,导致幔源岩浆上涌底侵下地壳而形成沿断裂带分布的花岗岩体;主脊处于碰撞向伸展环境过渡的时期,东坡区域此时应处于俯冲时期。  相似文献   

Cygnus A: stars, dust and cones     

Neal Jackson  Clive Tadhunter  & William B. Sparks 《Monthly notices of the Royal Astronomical Society》1998,301(1):131-141

We present new Hubble Space Telescope ( HST  ) continuum and spectral line images of the radio galaxy Cygnus A. The images show much complex structure in the central kpc². Continuum images show the central dust lane in detail, allowing detailed maps of E ( B  −  V ) to be constructed; the dust appears to follow a roughly Galactic extinction law. The emission-line components are resolved in the line images and investigated in detail. A clear 'opening cone' morphology is found, especially in the lines of Hα and [O  i ]. Blue condensations are seen in the south-eastern emission component and surrounding the central region. These are almost certainly due to star formation, which began <1 Gyr ago as deduced from the colour of the regions. More extended blue continuum is also seen and corresponds to the blue polarized component detected by other recent spectropolarimetric observations.  相似文献   

西安地区部分古遗址考古地磁研究          下载免费PDF全文

孟昭秦 《地质科学》1998,33(4):489-493

通过对陕西耀州窑遗址内4个古窑,临潼兵马俑一号坑,西铜一级公路经过黄堡工地开挖的两个五代窑,以及耀州窑博物馆仓库工地内开挖的一个金代窑和一个春秋窑遗址的古地磁研究,初步得出了西安地区古地磁场变化的规律,为鉴定从春秋到金代西安地区的古遗址、古文物提供了考古地磁学上的一个粗略的标准。  相似文献   

A classification system for the assessment of slope stability of terrains along highway routes in Jordan   总被引：2，自引：0，他引：2  

A. S. Al-Homoud  Y. Masanat 《Environmental Geology》1998,34(1):59-69

 The establishment of comprehensive development plans, in general, and the proper selection of highway routes, in particular, require an assessment of landslides or instability hazards in the project sites. The frequent landslides that occurred along the routes of major highways in Jordan, and particularly along the Amman-Na'ur-Dead Sea highway and Irbid-Jerash-Amman highway, have substantially increased the cost of construction and caused a considerable delay in the completion of work. The study of many landslides that occurred in the last 25 years along the highway routes and in the sites of some major civil engineering projects in Jordan has led to the recognition of major factors that affect the stability of slopes, and thus the safety and economics of these projects. The geological formation, structural features, topographic characteristics, geometry, and climatic conditions were adopted as the basis for the classification of terrains in terms of their stability. Each factor has been assigned a rating to indicate its relative contribution to the overall stability according to engineering judgment and past experience. The areas have been classified into 5 groups according to their total stability rate. The simplicity, comprehensiveness, and accuracy are the main characteristics of the proposed classification. Its significance stems from its helpfulness as a guide to the geotechnical and highway engineers in assessing the overall stability of the alternative routes of proposed highway projects. Received: 3 December 1996 · Accepted: 29 April 1997  相似文献   

The working class, minorities and housing in Paris, the rise of fragmentations     

Catherine Rhein 《GeoJournal》1998,46(1):51-62

Which places are left to minorities in the housing and labour markets in metropolitan Paris? Over the last two decades, job structures have evolved dramatically, eroding the formerly prominent Paris working-class, shaking the social and political roots of its identity. These indicators would lead one to diagnose a growing fragmentation of metropolitan society. In the political debate, the burning issue of the crisis of suburbs has replaced outdated debate of the class struggle. This paper aims first to re-examine the interactions between social status and national origins, then analyses the housing conditions of different social strata, and finally demonstrates the pre-eminence of social status over national origins in the pattern of residential segregation.  相似文献   

腐泥煤变质系列热解色谱和氯仿沥青“A”的特点   总被引：2，自引：0，他引：2  

赵海舟 《中国煤田地质》1998,10(2):23-26

对滕县、淄博两煤田与腐殖煤共生的不同煤级的腐泥煤进行了热解和氯仿沥青“Ａ”的族组份分析,获得如下认识：热解的结果,Ｔｍａｘ、Ｓ１、Ｓ３、Ｉｐ全部高于共生腐殖煤,Ｉｔ全部低于共生腐殖煤,Ｓ２和Ｃｐ在低煤化阶段高于腐殖煤,而中,高煤化阶段则低于腐殖煤;氯仿沥青“Ａ”都随煤级的增高而减少,腐泥煤全部高于腐殖煤,腐泥煤从低煤级到高煤级其族组份的排序从饱和烃＞非烃＞芳烃＞沥青质变化到非烃＞芳烃＞沥青质＞饱和烃;而腐殖煤族组份的排序则从沥青质＞芳烃＞非烃＞饱和烃＞沥青质。  相似文献   

Chandra observations of neutron stars: an overview     

M. C. Weisskopf  M. Karovska  G. G. Pavlov  V. E. Zavlin  T. Clarke 《Astrophysics and Space Science》2007,308(1-4):151-160

We present an overview of Chandra X-ray Observatory observations of neutron stars. The outstanding spatial and spectral resolution of this great observatory have allowed for observations of unprecedented clarity and accuracy. Many of these observations have provided new insights into neutron star physics. We present an admittedly biased and overly brief review of these observations, highlighting some new discoveries made possible by the Observatory’s unique capabilities. This includes our analysis of recent multiwavelength observations of the putative pulsar and its pulsar-wind nebula in the IC443 SNR.   相似文献   

A PRELIMINARY RESEARCH ON THE CLIMATIC RECORDS OF LACUSTRINE DEPOSITS OF QINGTU LAKE IN THE LAST 6000 YEARS     

王乃昂  高顺尉 《中国地理科学(英文版)》1999,9(4):335-341

１　ＳＴＵＤＩＥＤＲＥＧＩＯＮＡＮＤＡＮＡＬＹＳＩＳＭＥＴＨＯＤＬｏｃａｔｅｄａｔｎｏｒｔｈｗｅｓｔｅｒｎｍａｒｇｉｎｏｆＴｅｎｇｇｅｒＤｅｓｅｒｔａｎｄ７０ｋｍｎｏｒｔｈｅａｓｔｏｆＭｉｎｑｉｎＣｏｕｎｔｙｉｎＧａｎｓｕＰｒｏｖｉｎｃｅ，ＱｉｎｇｔｕＬａｋｅｂｅｌｏｎｇｓｔｏｔｈｅＳｈｉｙａｎｇＲｉｖｅｒＤｒｙＤｅｌｔａ，ａｎｄｔｈｅａｌｔｉｔｕｄｅｉｓ１２９２－１３１０ｍ．Ｔｈｅｒｅｇｉｏｎｈａｓｔｈｅｃｈａｒａｃｔｅｒｏｆｔｅｍｐｅｒａｔｅｃｏｎｔｉｎｅｎｔａｌａｒｉｄｄｅｓｅｒｔｃｌｉ…  相似文献