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951.
移动GIS技术在土地变更调查中的应用   总被引:8,自引:0,他引:8  
介绍了GPS定位的高精度和PDA的便于携带、功能强大的特点,将二者集成用于土地变更调查。探讨了移动GIS应用于土地变更调查的技术方法,移动GIS的系统结构及其开发实践。  相似文献   
952.
谢波  肖东升 《测绘工程》2021,30(3):21-25
约束秩亏间接平差模型的法方程系数矩阵为分块矩阵,其左上角的子块矩阵秩亏,因此无法直接计算分块矩阵的凯利逆矩阵.利用矩阵运算,构建一个能直接求凯利逆的分块矩阵,进而推算出约束秩亏间接平差模型法方程系数矩阵的凯利逆的直接显性表达式.提出将约束条件看作虚拟观测,和原有的秩亏间接平差模型组合成新的误差方程,再和约束条件组成约束...  相似文献   
953.
垂直度控制和标高控制是确保高层和超高层建筑施工质量的关键,传统的高层或超高层建筑施工垂直度控制和标高控制方法存在着工作过程繁琐、效率低、精度难尽人意等若干问题,为了克服传统法的缺陷,提出了利用GPS技术进行高层或超高层建筑施工垂直度与标高控制的新思路,高层或超高层建筑施工垂直度与标高的GPS控制摆脱了传统方法对地面控制点的过度依赖,实现了对施工垂直度与标高的快速、高效、高精度控制,确保了施工质量。结合工程实例叙述了利用GPS技术控制高层或超高层建筑施工垂直度与标高的工作过程。  相似文献   
954.
ABSTRACT

Despite much attention paid to the topic of community in academic literature and policy documents, there is a relative lack of knowledge about what laypersons perceive as a local community. Based on data from a national survey, the authors examine how c.1400 Norwegians conceptualized local community – lokalsamfunn in Norwegian. They reveal some of the linguistic and conceptual aspects of local community as a term, in addition to tendencies and patterns among the survey responses. The respondents’ conceptualizations contained references to lokalsamfunn variously as a geographical area, people and relations, activities and involvement, attachment to place and people, and provider of local goods and services. Their main emphasis was on lokalsamfunn as a spatial unit. However, the responses contained relatively few references to the relational aspects of lokalsamfunn. The authors conclude that a common, lay understanding may be that lokalsamfunn is a vaguely defined but limited geographical unit filled with people who to varying degrees know each other and interact. Concerning policymaking aimed at fostering communal well-being, the authors hold that any community-based programming requires intricate knowledge of the people who form the community, since without community interaction and a degree of social cohesion any envisioned programmes may not succeed.  相似文献   
955.
This paper describes the design, expectations, and prototyping of a new allsky survey, called 2MASS (Two Micron All Sky Survey) to be carried out with the new generation of infrared array detectors.  相似文献   
956.
利用地面垂直形变测量资料研究了1990年4月26日青海共和Ms6.9地震的震源机制。通过反演得出这次地震是由逆冲倾滑为主的断层错动引起的。该断层走向102°,倾向SW,倾角46°,长40km,宽9km,断层上部边界至地面的垂直距离3km,下部边界至地面的垂直距离10km。逆冲倾滑错距79cm,伴以错距5cm的左旋走向滑动。这是一次低应力降(3.8MPa)的板内地震,应变降为5.7×10~(-5),地震矩9.8×10~(18)N°m,能量释放5.0×10~(14)J。由反演得到的共和地震的震源机制与等震线的形态、余震的空间分布以及共和盆地断层交汇的特征总体上是一致的。  相似文献   
957.
BOOK REVIEWS     
Books reviewed in this article: The Mexican Colonial Copper Industry. Elinore M. Barrett . The Control Revolution: Technological and Economic Origins of the Information Society . James R. Beniger . Land Degradation and Society . Piers M. Blaikie And Harold C. Brookfield , Eds . La carte, mode d'emploi. Roger Brunet . France: les dynamiques du territoire . Roger Brunet AND Jacques Sallois , EDS. At the Crossroads—The Mineral Problems of the United States . Eugene N. Cameron . A Census of One Billion People , Papers for International Seminar on China's 1982 Population Census. Li Chengrui , ED. Les Milieux “Naturels” du Globe . Jean Demangeot . The Geophysiology of Amazonia: Vegetation and Climate Interactions : Robert E. Dickinson , ED. Tenn-Tom Country . James F. Doster And David C. Weaver . Family Farming in Europe and America . Boguslaw Galeski And Eugene Wilkening , EDS. The Geography of Urban Transportation . Susan Hanson , Ed. Combating Desertification in Developing Countries . J. K. Jain , ED. Cartography in France—1660–1848. Science, Engineering and Statecraft . Josef W. Konvitz . Distribution of Distances in Pregeographical Space . Hans Kuiper . Physical Geography Lab Manual: A New Experimental Approach . Neal G. Lineback And John M. Harlin . Physical Geography: A Landscape Appreciation , 2nd ed. Tom L. Mc Knight . The Desert Is No Lady: Southwestern Landscapes in Women's Writing and Art . Vera Norwood And Janice Monk , EDS. France: A Geographical, Social, and Economic Survey . Philippe Pinchemel , translated, by D. Elkins and T. H. Elkins. Gene Banks and the World's Food . Donald L. Plucknett , Nigel J. H. Smith , J. T. Williams , And N. Murthi Anishetty . Latin American Development: Geographical Perspectives . David Preston , Ed. Making Sense of Development: An Introduction to Classical and Contemporary Theories of Development and Their Application to Southeast Asia . P. W. Preston . The History of the Countryside. Oliver Rackham . The Third World in Perspective . H. A. Reitsma AND J. M. G. Kleinpenning . The Industrial Geography of Australia . David C. Rich . The Recruiting Game , 2nd Ed., revised. John F. Rooney , JR. A Cultural Geography of North American Indians . Thomas E. Ross AND Tyrel G. Moore , EDS. Eastern Europe . Dean S. Rugg . Human Territoriality: Its Theory and History . Cambridge Studies in Historical Geography: 7. Robert David Sack . Experimental Fluvial Geomorphology . Stanley A. Schumm , M. Paul Mosley , AND William E. Weaver . The New Urban Landscape . David Schuyler . Atlas of American Women . Barbara Gimla Shortridge . Impacts of Hazardous Technology: The Psycho-Social Effects of Restarting TMI-1 . John Sorensen , Jon Soderstrom , Emily Copenhaver , Sam Carnes AND Robert Bolin . Modern Physical Geography , 3rd Ed., (Third Edition). Arthur N. Strahler AND Alan H. Strahler . India: Economic Resource Base and Contemporary Political Patterns . B. L. Sukhwal .  相似文献   
958.
分析了目前利用流动形变、重力、地磁复测资料进行地震预测所存在的困难,探讨了综合利用三种手段追踪应力场及地下介质动态的途径,提出了断层综合监测布点的原则,并介绍了依此原则所建的京西试验场的基本情况。  相似文献   
959.
丽江高美古的气象观测   总被引:1,自引:1,他引:0  
本文报道了1994年7月-1995年12月期间丽江高美古的云量、风向、风速、温度、湿度和温度日较差等气象要素的观测结果。  相似文献   
960.
Face-to-face interviews(n=860) were conducted to determine cash-gift behavior, cognition and complexity of social relations, and family water consumption for agricultural production in a typical oasis area in Northwest China. The survey results revealed cash gifts to be the second-largest expenditure(1,330 Yuan) for rural households, far beyond the average spending on health(854.1 Yuan) or education(890.8 Yuan). The amount of cash-gift expenditures indirectly reflects a family's social relations level, and our developed Social Relations Extent Coefficient—based on cash-gift and food expenditures—can directly reflect the extent or level of these relationships. Different types of farmers or farming families have different coefficients. The coefficient also shows how social station affects a family's water resource utilization, and how water is distributed among different types of farmers. Despite the current inequities, however, promotion of better agricultural techniques and large-scale cultivation in this area could help distribute water resources more equitably and effectively.  相似文献   
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