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91.
光谱预处理及其对星系/类星体分类结果的影响   总被引:1,自引:0,他引:1  
由于噪声、畸变和观测环境等因素的影响,在天体光谱自动处理之前,需要对它进行相应的预处理.研究巡天光谱的预处理(数据格式和流量标准化)对光谱自动分析的影响.分析了同数据格式对光谱及其谱线特征的影响和格式标准化研究的必要性;通过分析光谱流量数量级的不确定性及其特点,提出了流量数量级变化的基本模型,并给出了相应的标准化方法.通过星系和类星体的分类实验,结果表明:1)采用对数波长数据格式对光谱的自动分类更有利;2)验证了所提出的流量标准化模型的合理性,以及所给流量标准化方法良好的性能.特别需要指出的是,文献中通常采用的流量标准化方法在光谱自动分类中的效果反而是较差的.  相似文献   
92.
BOOK REVIEWS     
Book Reviewed in this article: Geography and the Third World. International Seminar, 14–18 May 1980, Kuala Lumpur, Malaysia . Ishmail Ahmad and Jamaluddin Md Jahi, eds. The Growth Dilemma: Residents' Views and Local Population Change in the United States . Mark Baldassare. Sport and Place: A Geography of Sport in England, Scotland & Wales . John Bale. The Deindustrialization of America: Plant Closings, Community Abandonment, and the Dismantling of Basic Industry . Barry Bluestone and Bennett Harrison. Selected Essays 1963–1975: Carl O. Sauer . Bob Callahen, ed. Housing and Planning in the Countryside . G. Clark. Conflict, Politics and the Urban Scene . Kevin R. Cox and R. J. Johnston, eds. Thematic Maps: Their Design and Production . David J. Cuff and Mark T. Mattson. Wine: A Geographic Appreciation . Harm Jan de Blij. USSR in Maps . J. C. Dewdney. Political Geography: A Contemporary Perspective . Ramesh D. Dikshit. Rethinking Human Adaptation . Rada Dyson-Hudson and Michael A. Little, eds. Sacred Sands: The Struggle for Community in the indiana Dunes . J. Ronald Engel. Geography of the Biosphere . A. Furley and Walter W. Newey. Disaster and Reconstruction . Robert Geipel. Glasgow: The Making of a City . Andrew Gibb. Design for Arid Regions . Giden S. Golany, ed. Urbanization and Cancer Mortality: The United States Experience, 1950–1975 . Michael R. Greenberg. Geology in the Nineteenth Century: Changing Views of a Changing World . Mott T. Greene. Colonización y Destrucción de Bosques en Panamá . Stanley Heckadon Moreno and Alberto McKay, eds. Urban Geography: A First Approach . David T. Herbert and Colin J. Thomas. The Visual and Spatial Structure of Landscapes . Tadahiko Higuchi. Climate from Tree Rings . M. K. Hughes, P. M. Kelly, J. R. Pilcher, and V. C. LaMarche, Jr., eds. The structure of Nineteenth Century Cities . James H. Johnson and Colin G. Pooley, eds. The American Planner: Biographies and Recollections . Donald A. Krueckeberg, ed. Urban Land Policy For the 1980s, the Message for State and Local Government . George Lefcoe, ed. Regional Planning: Evolution, Crisis and Prospects . Gill C. Lim, ed. Relevance and Ethics In Geography . Bruce Mitchell and Dianne Draper. China: The Geography of Development and Modernization . Clifton W. Pannell and Laurence J. C. MA. The Urban Retailing System . Robert B. Potter. Hants. Nonconventional Energy Resources . Philip R. Pryde. Caribbean Migrants: Environment and Human Survival on St. Kitts and Nevis . Bonham C. Richardson. Population and Resources . Harry Robinson. East Los Angeles: History of A Barrio . Ricardo Romo. Integrated Impact Assessment . Frederick A. Rossini and Alan L. Porter, eds. Environmental Aesthetics: Essays in Interpretation . Barry Sadler and Allen Carlson, eds. Earthwatch . Charles Sheffield. Field Techniques and Research Methods in Geography . Robert H. Stoddard. Haiti: Land of Poverty . Robert J. Tata. Weathering and Erosion: Sources and Methods in Geography . Stephen T. Trudgill. Once Beneath the Forest. Prehistoric Terracing in the Río Bec Region of the Maya Lowlands . B. L. Turner, II. The Historical Geography of Scotland since 1707 . David Turnock.  相似文献   
93.
In this paper, a multi-channel structure was developed to attenuate waves with various wave periods. By ignoring energy losses and the factor of channel width, a simple and straightforward method was used to tackle this problem. The theoretical solution showed that a single reflected channel structure could attenuate waves of a certain wave period, while a multi-channel structure could attenuate waves with various wave periods. If an interval of 0.05<relative water depth<0.15 is concerned, a structure consisting of four reflected channels could provide a transmission coefficient of less than 0.2. Experimental tests were conducted to verify the theoretical solutions. Both theoretical solution and experimental data indicated that waves with various wave periods would be effectively attenuated after passing through the multi-channel structure. Although some factors are neglected in treating this problem, the method is applicable. An allowed transmission coefficient can be provided by a multi-channel structure only if the computed peak value is not larger than that value.  相似文献   
94.
Rocks are naturally filled with cracks and pores that are saturated with one or more fluid phases. Many problems in rock mechanics, petroleum engineering, geophysics, etc. deal with cracks and discontinuities in rock formations. These problems should consider effects of a porous medium. Displacement discontinuity method (DDM) as an indirect boundary element method is particularly ideal for problems involving fractures and discontinuities. However, the DDM in its original form is limited to elastic problems. The paper uses a fundamental solution of a point displacement discontinuity in poroelastic medium to obtain the solution for a poroelastic DDM. Then it introduces a numerical formulation and implementation for the poroelastic DDM in a code named CEP-DDM (Constant Element Poroelastic DDM). The accuracy and validity of the proposed solution and the newly developed code are verified by two analytical solutions, another numerical solution, and some field measurements. These results showed good agreement between CEP-DDM and other methods’ results. The verifications prove the accuracy and applicability of the proposed numerical model in a wide range of real-world problems.  相似文献   
95.
During the late 1980s and early 1990s, cognitive science was included as one of the key disciplines in the emerging multidisciplinary field of geographic information science (GIScience). One of the key proponents and popularizers of the study of human cognition as part of GIScience – and one of its major researchers – has been Andrew U. Frank. In this essay, we review the history of Andrew Frank’s role as an innovator and champion for cognitive GIScience, and summarize some of his research contributions in this domain. Taken along with his contributions to other areas of GIScience, this review shows that Andrew Frank has been one of the primary figures in modern GIScience, and among its very broadest and intellectually-diverse contributors.  相似文献   
96.
针对现实中消费现象和消费研究日益显著现象,小文从传统消费地理研究思维定势和方法着手,疏理西方消费空间研究关注点的转变趋势:①包罗万象的消费研究对象和内容;②传统与现代新型多种消费空间类型的探讨;③对消费空间主体性与社会性的关注;④跨尺度空间与商品移动轨迹的新视角;⑤消费内涵的延伸。西方地理学家对消费的研究方法体现为传统地学区域和空间研究视角优势的发挥,以及批判性地继承大量的社会学理论和方法。西方地理学家对社会科学做出的贡献主要如下:①揭示消费空间不平衡关系和社会意义;②强调消费、消费者与消费空间的非均一、异质、流动特征,指出以消费者类型开展研究的弊端,质疑历史分析研究和消费阶段划分方法;③采用情景方法对主体与空间关系研究,揭示出多种消费空间存在的社会政治意义;④继承马克思政治经济学将生产和消费空间联系起来的研究方法,同时指出阶级视角对消费者多种差异性的忽视;⑤基于商品链、供给系统、商品循环和行动者网络等方法和学说的差异性视角及其政治立场,强调学说,尤其道德因素对社会实践的影响。  相似文献   
97.
中国成菱镁矿区带与关键科学问题   总被引:5,自引:0,他引:5  
赵正  白鸽  王登红  陈毓川  徐志刚 《地质学报》2014,88(12):2326-2338
我国菱镁矿资源丰富,储量巨大,目前位居世界首位.类型上以晶质菱镁矿为主,便于开发利用.晶质菱镁矿又以沉积变质型为主,集中分布在辽东地区,形成了世界级的大型—超大型菱镁矿集中区和生产基地,其次为成因上与超镁铁质杂岩密切相关的热液交代型和风化残积型,青藏班公湖成矿带可作为我国湖相沉积型菱镁矿找矿的重要靶区.本次在对全国62处菱镁矿矿产地资料系统梳理的基础上,深入总结了全国菱镁矿的成矿规律,进一步划分了菱镁矿的矿床类型,并划分出13个成菱镁矿带,编制了“中国菱镁矿成矿规律图”、“中国菱镁矿成矿体系图”和“中国成菱镁矿带分布图”等图件,为我国菱镁矿资源潜力评价的预测工作提供了理论依据.同时,本文对我国辽东超大型菱镁矿的成因机制问题和菱镁矿中镁的物质来源等关键科学问题展开了探讨.  相似文献   
98.
黄荪 《安徽地质》2010,20(1):74-76
安徽省首轮县级矿产资源规划规划期一般为2004年~2010年,现正进行修编准备。舒城县是一个以建材非金属矿为主的资源小县,对规划实施中存在的问题以及在规划修编中如何加以解决,使新规划更具针对性和可操作性,作者结合自身工作实际提出建议。  相似文献   
99.
岩石质量指标(RQD)是评价岩体完整性及质量分级的一个重要指标。针对矿区工程地质勘查规范中推荐的岩体质量评价方法,详细分析了岩石质量指标(RQD)在用于岩体分类与评价中存在的岩心长度的计算、采取率、硬度和结构对其赋值大小的影响,以及对规范理解的差异,提出了解决这些问题的有效方法与途径,为岩石质量指标(RQD)的正确应用及煤矿床岩体质量合理评价做了有益的探讨。  相似文献   
100.
随着世界各国乃至全球信息化和数字化的发展以及全球环境的日益恶化,有一项国际性的合作计划——“全球测图项目”正在进行。通过世界各国的合作,解决全球环境问题迫在眉睫。目前,国际上公认数字化全球地图是建立“全球空间数据基础设施”和“数字地球”的必要基础,全球地图在解决全球环境问题中发挥着越来越大的作用。  相似文献   
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