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921.
BOOK REVIEWS     
Book Reviewed in this article: Rabat: Urban Apartheid in Morocco . Janet Abu -Lughod . Marketplaces in a Developing Country: The Case of Western Nigeria . Isaac Ayinde Adalemo . Farming Development and Space: A World Agricultural Geography . Bernd Andreae . Section and Party: A Political Geography of American Presidential Elections, from Andrew Jackson to Ronald Reagan . J. Clark Archer and Peter J. Taylor . Women and Space: Ground Rules and Social Maps . Shirley Ardener , ed. European Progress in Spatial Analysis . R. J. Bennett , ed. The Origins of Academic Geography in the United States . Brian W. Blouet Geographic Perspectives on Global Problems . Ronald Reed Boyce . Seasonal Dimensions to Rural Poverty . Robert Chambers , Richard Longhurst and Arnold Pacey eds. The New Nationalism and the Use of Common Spaces: Issues in Marine Pollution and the Exploitation of Antarctica . Jonathan I. Charney , ed. Communications Tomorrow: The Coming of the Information Society . Edward Cornish , ed. The Design of Suburbia . Arthur Edwards . Explorer on the Northern Plains: Lieutenant Gouverneur K. Warren's Preliminary Report of Explorations in Nebraska and Dakota in the Years 1855–56–57. With an Introduction by Frank N. Schubert . The Changing Climate: Responses of the Natural Flora and Fauna . Michael J. Ford . Essentials of Physical Geography . Robert E. Gabler , Robert J. Sager , Sheila Brazier , and Daniel L. Wise. The Road to Jaramillo . William Glen . Valued Environments . John R. Gold and Jacquelin Burgess , eds. Proximity and Preference: Problems in the Multidimensional Analysis of Large Data Sets . Reginald G. Golledge and John N. Rayner , eds. A Search for Common Ground . Peter Gould and Gunnar Olsson , eds. Geography: Its History and Concepts . Arild Holt -Jensen . A Population Geography . Huw R. Jones . The Human Mosaic: A Thematic Introduction to Cultural Geography, 3rd ed. Terry G. Jordan and Lester Rowntree . Urban Social Geography: An Introduction . Paul Knox . The Anatomy of Job Loss: The How, Why and Where of Employment Decline . Doreen Massey and Richard Meegan . The Information Society as Post-Industial Society . Yoneji Masuda . Map Librarianship, 2nd ed. Harold Nichols . India: Cultural Patterns and Processes . Allen G. Noble and Ashok K. Dutt , eds. The God that Limps: Science and Technology in the Eighties . Colin Norman . Geography: An Introductory Perspective . Robert E. Norris , Keith D. Harries and John D. Vitek . The Politics of Technology Assessment . David M. O'Brien and Donald A. Marchand . Ethnic Segregation in Cities . Ceri Peach , Vaughan Robinson and Susan Smith , eds. Churches and Church Membership in the United States, 1980 . Bernard Quinn , Herman Anderson , Martin Bradley , Paul Goetting and Peggy Shriver . Energy in Australia: Politics and Economics . Hugh Saddler . Development from Above or Below? The Dialectics of Regional Planning in Developing Countries . Walter B. Stóuhr and D. R. Fraser Taylor , eds. Human Impact on the Ecosystem . Joy Tivy and Greg O'Hare . Plants and People: Vegetation Change in North America . Thomas R. Vale . The Mapmakers: The Story of the Great Pioneers in Cartography from Antiquity to the Space Age . John Noble Wilford .  相似文献   
922.
On the basis of bispectral analysis applied to the hourly data set of neutral wind measured by meteor radar in the MLT region above Bulgaria it was demonstrated that nonlinear processes are frequently and regularly acting in the mesopause region. They contribute significantly to the short-term tidal variability and are apparently responsible for the observed complicated behavior of the tidal characteristics. A Morlet wavelet transform is proposed as a technique for studying nonstationary signals. By simulated data it was revealed that the Morlet wavelet transform is especially convenient for analyzing signals with: (1) a wide range of dominant frequencies which are localized in different time intervals; (2) amplitude and frequency modulated spectral components, and (3) singular, wave-like events, observed in the neutral wind of the MLT region and connected mainly with large-scale disturbances propagated from below. By applying a Morlet wavelet transform to the hourly values of the amplitudes of diurnal and semidiurnal tides the basic oscillations with periods of planetary waves (1.5/20 days), as well as their development in time, are obtained. A cross-wavelet analysis is used to clarify the relation between the tidal and mean neutral wind variability. The results of bispectral analysis indicate which planetary waves participated in the nonlinear coupling with the atmospheric tides, while the results of cross-wavelet analysis outline their time intervals if these interactions are local.  相似文献   
923.
4D tropospheric tomography using GPS slant wet delays   总被引:20,自引:0,他引:20  
Tomographic techniques are successfully applied to obtain 4D images of the tropospheric refractivity in a local dense network of global positioning system (GPS) receivers. We show here how GPS data are processed to obtain the tropospheric slant wet delays and discuss the validity of the processing. These slant wet delays are the observables in the tomographic processing. We then discuss the inverse problem in 4D tropospheric tomography making extensive use of simulations to test the system and define the resolution and the impact of noise. Finally, we use data from the Kilauea network in Hawaii for February 1, 1997, and a local 4 × 4 × 40 voxel grid on a region of 400 km2 and 15 km in height to produce the corresponding 4D wet refractivity fields, which are then validated using forecast analysis from the European Center for Medium Range Weather Forecast (ECMWF). We conclude that tomographic techniques can be used to monitor the troposphere in time and space.  相似文献   
924.
Based on a case study in a Thai forest reserve, this article compares two modes of ‘reading’ the forest - official and local forest classification systems - and discusses how they imply different ideas about the forest, and how these competing knowledges interact with the politics of forest governance. Forest classification conventions are shown to slip, as ‘facts’ about the forest, from their origins in extraction-oriented forestry to the realm of conservation. Through a comparison of conventional vegetation classifications used in the state’s governance of the Thung Yai Naresuan Wildlife Sanctuary in Thailand, with the classificatory systems of resident Pwo Karen communities, this paper examines the slippage of conventional classifications through various uses and the emphases placed by competing representations of the forest within the context of conservation politics in Thailand. It was found that conventional classifications continued to prioritise the silvicultural potential of trees within a conservation context, downplaying other notions of forests - such as their importance to livelihoods and as lived spaces - which are present in Karen classifications.  相似文献   
925.
The Jurassic growth of mountain ranges along the southern edge of the Siberian platform occurred in an active tectonic setting related to the closure of the Mongol-Okhotsk Ocean. The oceanic subduction and subsequent continent collision events induced compressive deformations at the platform boundary. Understanding the paleogeography related to the Mesozoic closure of the Mongol-Okhotsk Ocean requires dating and correlation of the Jurassic Prisayan Formation in the Irkut basin and Tugnuyskaya Formation in southwestern Transbaikalia. This work presents structural and paleobotanic results within both formations. 40Ar/39Ar dating of underlying volcanics from the upper member of the Ichetuyskaya Formation is used to refine the age of the sediment series and provide probable correlation. The results show that the Tugnuyskaya Formation initiated at the end of the Middle Jurassic-beginning of the Late Jurassic and was not coeval with the Prisayan Formation, whose upper fine-grained members were deposited in the early Middle Jurassic. 40Ar/39Ar dating of volcanics from the upper member of the Ichetuyskaya Formation yielded a Middle Jurassic age of 167.7 ± 1.2 Ma (Bajocian to Bathonian). The paleogeographic data analysis based on facies and mineralogical composition of sediments and on a study of source areas from Sm-Nd data and the U-Pb ages of detrital zircons from the deposits in the southern Irkut basin indicates that the deposition of the Prisayan Formation was followed by the intensification of relief building along the southern edge of the Siberian Platform. Our geochronological data show that active tectonic deformations in southwestern Transbaikalia evidenced in the volcanoclastic Ichetuyskaya Formation in the Tugnuy basin also occurred during the Middle Jurassic. The uppermost sediments of the Tugnuy basin were deposited at the end of the Middle Jurassic-Late Jurassic in a quiet tectonic setting with low relief and lacustrine-boggy depositional environments.  相似文献   
926.
随着遥感技术的发展和自然资源事业对遥感应用需求的不断增多,通过遥感先行开展先行观测、先行探测、先行监测,强化自然资源数据的获取,提高调查的精度和速度,遥感技术正在促进自然资源调查程序和方式的转变.本文围绕新时代自然资源调查体系的新变化,提出了遥感先行的理念、目标及发展方向,认为:1)遥感先行是自然资源调查监测技术体系构建的重要内容,可实现对自然资源全要素、全覆盖、全天候、全尺度的调查监测;2)通过遥感技术方法体系的创新、遥感产品的转化应用等,可发挥遥感技术在矿产、生态、水、土、灾害等调查监测中的重要先行作用;3)"天-空-地"一体化的遥感综合观测技术是推动中国西部地区自然资源精准快速调查和全球尺度环境问题监测的最佳技术手段.  相似文献   
927.
928.
The fundamental theoretical framework of the Multisphere Tectonics of the Earth System is as follows: (1) It intends to extend the geotectonic studies from the crustal and lithospheric tectonics to the multisphere tectonics of the Earth system as a whole. (2) The global dynamics driven by both the Earth system and the cosmic celestial system: solar energy, multispheric interactions of the Earth system and the combined effects of the motions of celestial bodies in the cosmos system are the driving forces of various geological processes. (3) The Continent-Ocean transformation theory: the continent and ocean are two opposite yet unified geological units, which can be transformed into each other; neither continent nor ocean will survive forever; there is no one-way development of continental accretion or ocean extinction; the simple theory of one-way continental accretion is regarded as invalid. (4) The continental crust and mantle are characterized by multiple layers, with different layers liable to slide along the interfaces between them, but corroboration is needed that continents move as a whole or even drift freely. (5) The cyclic evolution theory: the development of Earth’s tectonics is not a uniform change, but a spiral forward evolution, characterized by a combination of non-uniform, non-linear, gradual and catastrophic changes; different evolutionary stages (tectonic cycles) of Earth have distinctive global tectonic patterns and characteristics, one tectonic model should not be applied to different tectonic cycles or evolutionary stages. (6) The structure and evolution of Earth are asymmetric and heterogeneous, thus one tectonic model cannot be applied to different areas of the world. (7) The polycyclic evolution of the continental crust: the continental crust is formed by polycyclic tectonics and magmatism, rather than simply lateral or vertical accretion. (8) The role of deep faults: the deep fault zones cutting through different layers of the crust and mantle usually play important roles in tectonic evolution. For example, the present-day mid-ocean ridge fault zones, transform fault zones and Benioff zones outline the global tectonic framework. Different tectonic cycles and stages of Earth’s evolution must have their own distinctive deep fault systems which control the global tectonic framework and evolutionary processes during different tectonic cycles and stages. Starting from the two mantle superplumes Jason (Pacific) and Tuzo (Africa), the study of the evolutionary process of the composition and structure of the crust and mantle during the great transformation and reorganization of the Meso-Cenozoic tectonic framework in China and the other regions of Asia is a good demonstration of theory of Multisphere Tectonics of the Earth System.  相似文献   
929.
传统地质数据管理与应用是参照数据库的外模式来设计数据结构和数据访问接口,在业务逻辑没有发生大的变动情况下,外模式发生更改后,需要修改应用程序才能适应新的数据库结构.鉴于此弊,在关系数据库视图机制的启发下,通过分析不同地质专业地质属性数据的特征,对地质数据库外模式的高度概括,形成用于地质业务分析评价所需的关键属性组成的元组集——控制字典表,基于控制字典抽象出面向地质行业的对象式数据模型、映射数据模型与地质数据的关系,并参照控制字典表的“数据结构”来设计数据访问接口,最终实现地质数据库的动态扩展,无需再修改应用程序,需要做的仅仅是修改控制字典与外模式之间的映射关系,以不变应万变.控制字典作为一个中间件,将用户对地质数据的操作和计算机对地质数据的处理分离开来,充分保证了程序和数据层的逻辑独立性.   相似文献   
930.
遥感作为一种高效的对地观测技术在社会各领域发挥着重大的作用,培养创新型遥感人才已成为我国高等院校的重要任务。本文以南京信息工程大学为例,阐述了遥感科学与技术专业创新型人才培养模式的整个过程。根据遥感科学与技术专业学科交叉的特点并结合我校气象行业的特色,确立了"强数理基础、宽大气口径、重遥感实践、培养具有气象应用特色的跨学科复合型创新人才"的培养目标。围绕人才培养目标,重点阐述遥感人才培养的过程的7个环节。最后以2010级遥感科学与技术专业学生的培养为典型案例,评价了我校遥感科学与技术专业创新型人才培养模式的培养质量。  相似文献   
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