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981.
作者于1995年到甘肃省的肃北蒙族自治县,天祝藏族自治县和兰州市的南郊山区进行实地恒星选址考察,认为在前二地境内有可能找到潜在的优良台址,但需要更多的实测资料证实。 相似文献
982.
Lawrence S. Grossman 《The Professional geographer》1984,36(4):444-454
To collect time-use data in Third World rural areas, researchers should use broad-focus studies that provide adequate coverage throughout the year and employ direct observation of activities. Various methods used by geographers to obtain time expenditure information are examined in relation to these criteria; certain weaknesses are discussed. An alternative method developed by Allen Johnson, an anthropologist, has particular advantages for geographers because it facilitates mapping spatial patterns of time use, calculating average distances traveled to activities, and computing time spent on movement. 相似文献
983.
984.
《The Professional geographer》1986,38(4):430-457
Book Reviewed in this article: Latin America: Case Studies . Richard G. Boehm and Sent Visser Locality and Rurality: Economy and Society in Rural Regions . Tony Bradley And Philip Lowe The City and the Grassroots . Manuel Castells Geopolitics and Conflict in South America. Quarrels among Neighbors . Jack Child Post-Industrial America: A Geographical Perspective . David Clark Coastal Research: UK Perspectives . Malcolm W. Clark A Rural Policy for the EEC? Hugh Clout Peasant Agriculture in Assam: A Structural Analysis . M. M. Das . Environmental Change and Tropical Geomorphology . I. Douglas and T. Spencer Advances in Abandoned Settlement Analysis: Application to Prehistoric Anthrosols in Colombia, South America . Robert C. Eidt Measuring Culture . Jonathan L. Gross and Steve Rayner North America: A Human Geography . Paul Guinness and Michael Bradshaw A Geographical Bibliography for American Libraries . Chauncy D. Harris et al. Geography and the Urban Environment: Progress in Research and Applications, Vol. VI . D. T. Herbert and R. J. Johnston Changes in Global Climate: A Study of the Effect of Radiation and Other Factors During the Present Century . K. Ya . Kondrat'ev . Rural Development and the State: Contradictions and Dilemmas in Developing Countries . David A. M. Lea and D. P. Chaudhri The Martial Metropolis: U.S. Cities in War and Peace . Roger W. Lotchin The Climate of the Earth . Paul E. Lydolph . Weather and Climate . Paul E. Lydolph . Spatial Divisions of Labor: Social Structures and the Geography of Production . Doreen Massey . Panorama of the Soviet Union . N. Mikhailov . Soviet Armenia . K. S. Demirchian . USSR: Geography of the Eleventh Five-Year Plan Period . K. Spidchenko . Planung und Verwirklichung der Wiener Ringstrassenzone (Planning and Materialization of the Ringstrasse-Zone of Vienna). Kurt Mollik , Hermann Reining , Rudolf Wurzer . The American West Transformed: The Impact of the Second World War Gerald D. Nash . An Overview of the Survey of Income and Program Participation . Dawn Nelson , David Mc Millen, and Daniel Kasprzyk . Phenomenology, Science and Geography: Spatiality and the Human Sciences . John Pickles . Biological Diversification in the Tropics . Ghillean T. Prance Die Wanderviehwirtschaft im gebirgigen Westen der U.S.A. und ihre Auswirkungen im Naturraum . Gisbert Rinschede . Social and Economic Aspects of Radioactive Waste Disposal: Considerations for Institutional Management . World-Wide Weather . K. Takahashi Coastal Geomorphology in Australia . B. G. Thom Settlement System in Rural India: A Case Study of the Lower Ganga-Yamuna Doab . Ram Chandra Tiwari . Computer Programming for Geographers . David J. Unwin and John A. Dawson . Late Quaternary Environments of the Soviet Union . A. A. Velichko, ed . H. E. Wright , Jr. and C. W. Barnosky Ethics in Planning . Martin Wachs 相似文献
985.
In this paper, we highlight the way Singapore commemorates its involvement during the Second World War. After briefly tracing the genesis of war commemoration within the nation, we turn to one specific problematic--the gendered portrayals of the war within a particular war memorial in Singapore, the Changi Chapel and Museum. Through a reading of landscape texts, interviews with key figures, visitors and other ethnographic data, we explore the specific ways in which women have either been omitted or stereotypically represented within the site. We proceed to provide possible reasons for this, arguing how the male-centric focus of the site may be due to the perpetuation of hegemonic ideals of war as being a traditionally “male” terrain, and the fact that “silence” is often part of women’s approach to their war experiences. We also argue that gendered portrayals of the war within the site is also an unconscious product of the patriarchal nature of the Singapore state and nation-building endeavours that have placed limits on a more substantial inclusion of women’s stories vis-à-vis the men’s. 相似文献
986.
Seismic wave amplification: Basin geometry vs soil layering 总被引:1,自引:0,他引:1
J.F. Semblat M. Kham E. Parara P.Y. Bard K. Pitilakis K. Makra D. Raptakis 《Soil Dynamics and Earthquake Engineering》2005,25(7-10):529-538
987.
D.G. Raptakis M.V. Manakou F.J. Chvez-García K.A. Makra K.D. Pitilakis 《Soil Dynamics and Earthquake Engineering》2005,25(11):871-887
Euroseistest is currently the longest running test site in the world. It was originally defined as the 2D cross-section of the Mygdonian basin going from Profitis to Stivos villages. In this paper, we present the first results of the effort to extend the idea of test site to a larger portion of the whole sedimentary structure, i.e. the extension of the idea of Euroseistest from a 2D to a 3D structure. To this end we have compiled available geological and geotechnical information. We have analyzed microtremor and earthquake data recorded seven years ago, that had not been thoroughly exploited. We present the results of the analysis of H/V spectral ratios from microtremors recorded at 195 sites, and from earthquake records at 14 stations. The results are validated through comparison with the well studied 2D cross-section. In addition to this, the geometry of the edges of the basin has been deduced from electrical tomographies. The synthesis of all these data allowed us to propose reliable map of dominant frequencies throughout the basin, a good constrain on the geometry of the basin at the edges, and shear-wave velocity profiles at some points. Our results indicate that average shear-wave velocity is not constant throughout, and thus the dominant frequency map is not a faithful image of the geometry of the basin. We have also obtained a reliable estimate of the site response throughout the basin. The results have been used to plan an additional measurement campaign, and are currently used to compute site response using a 3D seismic modelling code. We expect that the usefulness of Euroseistest to understand site effects in 3D geological structures will be as large as it has been in its 2D phase. 相似文献
988.
989.
Combining multivariate statistical analysis with geographic information systems mapping: a tool for delineating groundwater contamination 总被引:5,自引:0,他引:5
Multivariate Statistical Analysis (MSA) has successfully been coupled with geographic information system (GIS) mapping tools to delineate zones of aquifer contamination potential. While delineating contaminants is key to site remediation, it is often compromised by a poor understanding of hydrogeologic conditions, and by uncertainties in contaminant observations. MSA provides improved estimates of contamination potential by augmenting observed contaminant concentrations with auxiliary information from other water-quality parameters. GIS is useful for organizing and managing water-quality information by visually communicating large amounts of information. The proposed method first establishes appropriate areal extents, GIS coverages, and scales for displaying groundwater contamination concentrations of tritium and the volatile organic contaminants trichloroethylene (TCE) and tetrachloroethylene (PCE) at the Savannah River Site, South Carolina, USA. Principal components analysis is used to group variables that are most indicative of contamination potential. Tritium contamination potential is best represented as the combination of tritium with the cations Al, Mg, Na and total dissolved solids, while PCE contamination potential is predicted using PCE and Cl. Maps of contamination potentials for 1993–1995 geochemical data compare favorably with measured contaminant concentrations during 1999. Cluster analysis of water-quality data groups geochemical and contaminant concentrations into zones of homogeneous behavior.
Resumen El Análisis Estadístico Multivariado (AEM) se ha acoplado con éxito con herramientas cartográficas del Sistema de Información Geográfico (SIG), para delinear zonas de potencial contaminación de acuíferos. En tanto que la delimitación de contaminantes es importante para recuperación del sitio, ella está a menudo amenazada por una comprensión pobre de las condiciones hidrogeológicas, y por las incertidumbres en las observaciones del contaminante. El AEM proporciona estimaciones mejoradas de contaminación potencial al aumentar las concentraciones observadas del contaminante, con la información auxiliar de otros parámetros de calidad de agua. El SIG es útil para organizar y manejar la información de calidad de agua, a través de la comunicación visual de cantidades grandes de información. El método propuesto establece primero magnitudes de área apropiadas, el área cubierta por el SIG, y las escalas para mostrar las concentraciones de contaminación del agua subterránea, a partir de tritio y de contaminantes orgánicos volátiles como tricloroetileno (TCE) y tetracloroetileno (PCE) en el sitio del Río al Savannah, Carolina del Sur, EE.UU. El análisis de componentes principales se usa para agrupar variables que son más indicativas de contaminación potencial. El potencial de contaminación Tritio, se representa mejor como la combinación de tritio con los cationes Al, Mg, Na y los sólidos disueltos totales, mientras la contaminación potencial de PCE se predice usando PCE y Cl. Los mapas de potenciales de contaminación para los datos geoquímicos de 1993–1995 se comparan favorablemente con las concentraciones medidas del contaminante durante 1999. El análisis de racimo hecho en datos de calidad de agua, agrupa concentraciones geoquímicas y concentraciones del contaminante en las zonas de comportamiento homogéneo.
Résumé L’Analyse Statistique Multivariée (ASM) a été couplée avec succès avec les outils cartographiques des Sytèmes d’Information Géographique (SIG), afin de délimiter les zones à potentiel de contamination des aquifères. Alors que la connaissance de l’extension des contaminants est primordiale pour la réhabilitation des sites, elle est fréquemment compromise par une compréhension limitée du contexte hydrogéologique, et par les incertitudes sur l’observation des contaminants. L’ASM fournit une meilleure estimation du potentiel de contamination, en complétant les concentrations observées en contaminants par des informations annexes issues d’autres paramètres qualitatifs. Les SIG, par leurs capacités à conjuguer visuellement de grandes quantités d’information, sont utiles pour organiser et gérer les informations sur la qualité de l’eau. La première étape de la méthode proposée consiste à définir les limites spatiales appropriées, les couvertures SIG, ainsi que les échelles de visualisation des concentrations en contaminants des eaux souterraines, soit le tritium et les composés organiques volatiles trichloroéthylène et tetrachloroéthylène, sur le site de la rivière Savannah (Californie du Sud, USA). L’analyse en composantes principales est utilisée afin de regrouper les variables caractérisant de manière optimale le potentiel de contamination. Le potentiel de contamination en tritium est représenté le plus significativement par la combinaison du tritium, des cations Al, Mg et Na, et des solides dissous totaux (TDS). Le potentiel de contamination en tétrachloroéthylène est quant à lui estimé en utilisant le tetrachloroéthylène et Cl. Les cartes des potentiels de contamination établies sur les données géochimiques de la période 1993–1995 renvoient une image comparable aux concentrations en contaminants effectivement mesurées en 1999. Une analyse de groupement des données sur la qualité de l’eau rassemble les concentrations géochimiques et en contaminants dans des zones aux comportements homogènes.相似文献
990.
Havvanur Kl Pelin Tohumcu
zener Atilla Ansal Mustafa Yldrm Kutay
zaydn enol Adatepe 《Engineering Geology》2006,86(4):238-255
A microzonation study is performed as a part of the Zeytinburnu Pilot Project within the framework of the Earthquake Master Plan for Istanbul to determine the effects of local soil conditions on the earthquake forces that will act on structures. For this purpose, detailed geological and geotechnical studies are conducted at the site, a geological map which demonstrates the local geological features of the site is prepared, and the site is classified with respect to the dynamic behaviour based on the data gathered from the soil borings. In order to investigate the effects of local soil conditions on the dynamic behaviour, site response analyses are performed with the computer code EERA by utilizing the findings of field and laboratory investigations. The behaviour of the region during a probable earthquake is investigated through one dimensional response analyses and microzonation maps are prepared with respect to ground shaking intensity in accordance with the new microzonation manual [Ansal, A., Laue, J., Buchheister, J., Erdik, M., Springman, S., Studer, J., and Koksal, D., 2004. “Site characterization and site amplification for a seismic microzonation study in Turkey” 11th Int. Conference on Soil Dynamics and Earthquake Engineering and 3rd Earthquake Geotechnical Engineering, San Francisco; Studer, J. and Ansal, A., 2004. Belediyeler için Sismik Mikrobölgeleme El Kitabı, Araştırma Raporu, Afet İşleri Genel Müdürlüğü, Bayındırlık ve İskan Bakanlığı, Afet Risk Yönetimi Dünya Enstitüsü]. 相似文献