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71.
文章采用基于集对分析法的社会、经济与生态环境协调发展模型研究雷州半岛海岸带主体功能区划,确定边界范围,构建评价指标体系。将整个雷州半岛作为海岸带,指标体系划分为三大类共27个指标。赤坎区、坡头区、麻章区属于基本协调发展;开发区(含东海)、遂溪县、雷州市、吴川市、徐闻县和廉江市属于高度协调发展;霞山区属于弱协调或不协调发展。雷州半岛各区域社会、经济发展对环境损害较小。霞山区、开发区(含东海)划分为重点开发区,遂溪县、雷州市、廉江市、吴川市和徐闻县划分为限制开发区,禁止开发区单独划出,包括3个国家级自然保护区、1个国家级风景名胜区和2个国家森林公园。  相似文献   
72.
通过对现有网络地图中国界显示存在的问题进行深入分析,按照网络地图国界显示的基本原则,探讨了网络地图国界自适应显示及符号化的方法。并基于Supermap为中国国界管理信息系统制作了一套国界网络地图。  相似文献   
73.
介绍《中华人民共和国省级行政区域界线详图集》的编制过程,叙述图集作业过程中的主要技术指标和编制方法,对带状分幅和抄接边处理等重难点地方进行详细的介绍。  相似文献   
74.
大陆盆地的聚敛-闭合过程研究:以塔里木盆地为例   总被引:1,自引:0,他引:1  
印度与欧亚大陆第三纪以来碰撞汇聚,造成亚洲大陆内部强烈缩短变形。塔里木盆地如何发生相应的变形调节和应变分解,成为中亚板内构造的重要问题。塔里木陆块新生代以来被板内造山带及走滑断裂系环绕,盆地内部以刚性为特征,未发生强烈构造变形。区域大断裂与塔里木盆地的冲断、走滑构造边界共同作用,形成盆地边缘复杂的构造系。其新生代构造变形主要集中于盆地的构造边界上,4条构造边界显示差异性的运动特征和构造交切关系。盆地边缘构造带叠加并向盆内扩展,造成盆地总体上水平缩短,并发生应变分解。盆地内部发生沉积-构造分异,发育前陆盆地、前缘隆起、复合前陆盆地、拉分盆地等单元。其中,盆地西北缘及西南缘发生陆内俯冲,形成前陆盆地及前陆冲断带,对盆内构造演化有重要影响。区域构造研究表明,塔里木盆地新生代主要发生了4期区域构造变形,第三纪以来还发生顺时针旋转。大陆盆地构造边界上的运动组合、盆内不均匀阻挡和滑脱拆离,造成其变形扩展方式的差异,并影响盆内单元构造演化。因此,塔里木盆地是认识大陆盆地聚敛与闭合过程的天然实验室。  相似文献   
75.
The Yenisei Range and the adjacent territories in the east are subdivided into (1) the Mid-Angara intracratonic depression; (2) the Yenisei pericratonic trough; and 3) a marginal oceanic block, the Isakovka-Predivinsk area. The lower part of the Riphean succession is subdivided into two principally different sedimentary complexes — the Lower Sukhoi Pit Subgroup and the Upper Sukhoi Pit Subgroup (the Pogoryui-Alad'in interval of the succession). The fundamental nature of the events that separate these two complexes and the characteristic, rhythmically bedded structure of the Upper Sukhoi Pit Subgroup allow the latter to be ranked a separate straton, the Bol'shoi Pit Group. Its lower boundary is associated with the Grenvillian events commencing with the emplacement of the Teya granite-gneiss domes and other intrusive complexes dated at 1100–1000 Ma. In the sedimentation record these events are manifested as a sudden change from the slate complex, for which we keep the name Sukhoi Pit Group, to the rhythmically bedded succession of the Bol'shoi Pit Group. The latter is interpreted as a product of uproofing of an elevated hinterland to the west. Insofar as the amplitude of this elevated area decreases progressively toward the Mid-Angara trough, the Bol'shoi Pit erosional unconformity and the associated interval of nondeposition are absent from the area. In the west of the Yenisei Range, in contrast, there is a major stratigraphic gap in the sequence, which is associated with the aforementioned events. The hypothesis on intensive events separating the deposition of the Bol'shoi Pit Group of the Kerpylian Horizon and the Tungusik Group of the Lakhandinian Horizon is not supported by the new data. The change from carbonate facies into siliciclastics in the west was misinterpreted as an erosional unconformity, with basal deposits corresponding to the lower boundary of the Tungusik Group. The occurrence of the Upper Tungusik deposits overlying much older rocks is a result of the pre-Bol'shoi Pit erosion and the gradual expansion of the Tungusik transgression. Thus, there are no grounds to argue for significant pre-Lakhandinian events in the region. Hence, the Kerpylian and Lakhandinian in the Yenisei Range, as well as in other parts of the Siberian Craton, constitute two parts of a larger supraregional straton, which corresponds to the lower half of the Upper Riphean and is designated here the Mayanian. The fundamentally different nature of the events associated with the next, Baikalian stage of the development allows its tripartite subdivision in the region. Deposition of the Lower Baikalian (the Oslyanka Group) was preceded by the crustal extension at the junction between the continental and oceanic blocks and, possibly, the formation of one of the Yenisei Range ophiolite complexes, followed by the emplacement of the Tatarka-Ayakhta batholiths at around 850 Ma. Fragments of both complexes are found as clasts in the basal conglomerates of the Middle Baikalian Chingasan Horizon. The specific character of the pre-Baikalian events determines their apparently poor expression in the sedimentation (weaker metamorphism of the Oslyanka deposits compared with the Tungusik Group). Even the activity leading to the formation of the Tatarka-Ayakhta granites cannot be regarded as a full-scale orogenic process. Collisional events separating the Lower and Middle Baikalian are manifested as the erosional unconformity at the base of the Chingasan Group and the emplacement of the Glushikha granites (760–730 Ma). The Middle Baikalian age of the Chingasan deposits is constrained by the data from paleontology, historical geology, and geochronology. Furthermore, the presence of glacial deposits renders this straton as a global stratigraphic marker. Further expansion of transgression in the Upper Baikalian is linked to another important event, but additional paleontological and geochronological information is needed to date the Upper Baikalian (Chapa Group) more accurately. The Baikalian events synchronously manifested themselves in all structural-facies zones of the Yenisei Range and are coeval to structural complexes from adjacent areas of the Siberian Craton. The tripartite Baikalian, therefore, has a potential for being included into the General Scale of the upper Upper Riphean.  相似文献   
76.
结合典型工程实例,采用在土体侧向边界节点处用弹簧并联阻尼器来进行模拟,在平面应变单元和桩体梁单元连接处用约束方程的方法进行节点耦合、满足连续条件,选择桩、土、荷载参数,用整体有限元方法进行桩-土-结构相互作用体系的地震反应分析。重点讨论了三种不同的上部结构刚度对桩基地震内力的影响,得到了在水平地震荷载作用下上部结构刚度的增大将增大桩基的内力及水平位移,且桩顶及桩身处于第一个软硬土层交界面处的截面的内力尤为突出等结论。关键词:上部结构刚度改变;桩-土-结构相互作用;弹性-阻尼边界;地震反应分析  相似文献   
77.
介绍了行政界线属性精度自动检查的必要性,分析了属性精度的质量元素、质量特点和常见错误,探讨了属性精度自动检查的程序实现方法,并介绍该方法在广东省行政界线采集与建库项目中的应用情况.实践证明该方法是有效的,可显著提高检查效率,确保成果质量.  相似文献   
78.
本文讨论了自然系列地图编制中的一个重要问题——自然界线之间的统一协调。作者通过对自然界线的定性、定量研究,阐述了自然界线及其相互联系的特征。并在此基础上提出了自然系列地图轮廓界线统一协调的主要方法和措施。  相似文献   
79.
BOOK REVIEWS     
Book Reviewed in this article: Women, Work, and Ideology in the Third World . Haleh Afshar, ed. The Birth of the National Park Service. The Founding Years 1913–33 . Horace M. Albright Theatres of Accumulation: Studies in Asian and Latin American Urbanization . Warwick Armstrong and T.G. McGee. New Tools for Social Scientists, Advances and Applications in Research Methods . William D. Berry and Michael S. Lewis -Beck , eds . Uncertain Dimensions: Western Overseas Empires in the Twentieth Century . Raymond F. Betts. Geography of Sugar Cane . Helmut Blume. The Mines of Neptune: Minerals and Metals from the Sea . Elisabeth Mann Borgese. Geographical Dimensions of Energy . F.J. Calzonetti and B.D. Solomon, eds. Statistical Methods for Geographers . W. A. V. Clark and P. L. Hosking. In The Wake of Columbus, Islands and Controversy . John DeVorsey, Jr., and John Parker, eds. Housing, States and Localities . Peter Dickens, Simon Duncan, Mark Goodwin and Fred Gray. Physician Location and Specialty Choice . Richard L. Ernst and Donald E. Yett. Practical Ecology for Geography and Biology: Survey, Mapping, and Data Analysis . D.D. Gilbertson , M. Kent and F.B. Pyatt Large Scale Water Transfers: Emerging Environmental and Social Experiences . Genady N. Golubev and Asit K. Biswas, eds. The Nature of the Environment . Andrew Goudie. Planning for Population Change . W.T.S. Gould and R. Lawton. The Niger and its Neighbors: Environmental History and Hydrobiology. Human Use and Health Hazards of the Major West African Rivers . A.T. Grove, ed. Remote Sensing of Ice and Snow . Dorothy K. Hall and Jaroslav Martinec. Atlas of Antebellum Southern Agriculture . Sam Bowers Hilliard. Galilee Divided; The Israel-Lebanon Frontier, 1916-1984 . Frederic C. Hor . Plains Country Towns . John C. Hudson. Agricultural Geography: A Social and Economic Analysis . Brian W. Ilbery. Industry in the 1980s: Structural Change and Interdependence . U.N. Industrial Development Organization. Crabgrass Frontier: The Suburbanization of the United States . Kenneth T. Jackson. The Industrial Geography of Italy . Russell King. Studies in Linguistic Geography: The Dialects of English in Britain and Ireland . John M. Kirk, Stewart Sanderson, J.D.A. Widdowson, eds. Tourism: A Community Approach . Peter E. Murphy. Cities and Services: The Geography of Collective Consumption . Steven Pinch. An Historical Geography of Europe 1800–1914 . Norman J. G. Pounds. An Introduction to Human Ecology Research on Agricultural Systems in Southeast Asia . A. Terry Rambo and Percy E. Sajise, eds. Discovering Past Landscapes . Michael Reed, ed. Managing the Ocean: Resources, Research, Law . Jacques G. Richardson, ed. Carta fitosociologica de la transecta botanica de la Patagonia Austral . F.A. Roig , Juan Anchorema , Orlando Dollenz , A.M. Faggi and Eduardo Mandez Intermetropolitan Migration in Canada: Changing Determinants over Three Decades . R. Paul Shaw. Chinese Cities—The Growth of the Metropolis since 1949 . Victor F. Sit, ed. Urbanization in the World-Economy . Michael Timberlake, ed. The Al Business: Commercial Uses of Artificial Intelligence . Patrick H. Winston and Karen A. Prendergast, eds.  相似文献   
80.
BOOK REVIEWS     
Book Reviewed in this article: Hillslope Processes. Binghamton Symposia in Geomorphology International Series: 16. Athol D. Abrahams , ed. The Atlas of Central America and the Caribbean. The Diagram Group . The Cultural Atlas of Islam. Isma'il R. al Faruqi and Lois Lamaya'al Faruqi . Atlas of Israel Contemporary Africa: Development, Culture and the State. Morag Bell . Fundamentals of Physical Geography. David Briggs and Peter Smithson . The Bicentennial Census: New Directions for Methodology in 1990. Constance F. Citro and Michael L. Cohen , eds . World Patterns of Modern Urban Change: Essays in Honor of Chauncy D. Harris. Michael P. Conzen , ed . New Directions for Agriculture and Agricultural Research: Neglected Dimensions and Emerging Alternatives. Kenneth A. Dahlberg , ed . Water Resources Atlas of Florida. E.A. Fernald and D.J. Patton , eds . Landscape Ecology. R.T.T. Forman and M. Godron . The Myth of the North American City: Continentalism Challenged. Michael Goldberg and John Mercer . The Permafrost Environment. Stuart A. Harris . Climate and Circulation of the Tropics. Stefan Hastenrath . The Island of South Georgia. Robert Headland . The Making of Urban Europe, 1000-1950. Paul M. Hohenberg and Lynn Hollen Lees . Bombay in Transition: The Growth and Social Ecology of a Colonial City, 1889–1980. Meera Kosambi . Plant Closings; Public or Private Choices? Richard B. McKenzie , ed . Malaysia: Tradition, Modernity and Islam. R.S. Milne and Diane K. Mauzy . Technology on the Frontier: Mining in Old Ontario. Dianne Newell . The Maritime Political Boundaries of the World. J.R.V. Prescott . Tall Office Buildings in the United States. James W. Pygman and Richard Kateley (Real Estate Research Corporation). Technology, Regions, and Policy. John Rees , ed . The United States and the Regional Organization of Asia and the Pacific: 1965-1985. W.W. Rostow . Renewable Energy: Progress, Prospects. Stephen W. Sawyer Wisconsin Foundations. Gwen Schultz . Dwelling, Place and Environment: Towards a Phenomenology of Person and World. David Seamon and Robert Mugerauer , eds . Power and Place: Canadian Urban Development in the North American Context. Gilbert A. Stelter and Alan F.J. Artibise , eds . Small Firms in Regional Economic Development: Britain, Ireland and the United States. D. J. Storey , ed . Mathematical Methods in Human Geography and Planning. A. G. Wilson and R. J. Bennett . El Niño North: Niño Effects on the Eastern Subarctic Pacific Ocean. W. S. Wooster and D. L. Fluharty , eds . The Soviet Iron and Steel Industry. Craig ZumBrunnen and Jeffrey Osleeb .  相似文献   
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