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971.
《The Professional geographer》1986,38(3):295-316
Book Reviewed in this article: Marine Resources of Kuwait: Their Role in the Development of Non-oil Resources . Fatimah H. Y. al -Abdul -Razzak Recollections of a Revolution: Geography as Spatial Science . Mark Billinge , Derek Gregory and Ron Martin Entre l'Eden et l'Utopie . Luc Bureau Developments in Political Geography . M. A. Busteed The Elements of Graphing Data . William S. Cleveland Rural Resource Management . Paul J. Cloke and Chris C. Park Third World Atlas . Ben Crow and Alan Thomas Exploitation, Conservation, Preservation: A Geographic Perspective on Natural Resource Use . Susan L. Cutter , Hilary Lambert Renwick, and William H. Renwick . Wine Regions of the Southern Hemisphere . Harm Jan de Blij Regional Development: Problems and Policies in Eastern and Western Europe . George Demko The Geographer at Work . Peter R. Gould Change in the Amazon Basin . John Hemming Geography Since the Second World War . R. J. Johnston and P. Claval Urbanization in China: Town and Countryside in a Developing Economy 1949–2000 A.D. , R. J. R. Kirkby Transport and Communications for Pacific Microstates: Issues in Organisation and Management . Christopher C. Kissling Fluvial Forms and Processes . David Knighton The Urban Millennium . Josef W. Konvitz Technological Transition in Cartography . Mark Stephen Monmonier Field Guide to Soils and the Environment: Applications of Soil Surveys . Gerald W. Olson Northern Australia: The Arenas of Life and Ecosystems on Half a Continent . Don Parkes A Killing Rain: The Global Threat of Acid Rain . Thomas Pawlick From the Family Farm to Agribusiness: The Irrigation Crusade in California and the West, 1850–1931 . Donald J. Pisani Hybrid Maize Diffusion in Kenya . Franz -Michael Rundquist Warning and Response to the Mount St. Helens Eruption . Thomas F. Saarinen and James L. Sell Coastal Geomorphology in Australia . B. G. Thom Tropical Rain Forests of the Far East , 2nd ed . T. C. Whitmore The Dark Side of the Earth . Robert Muir Wood Categorical Data Analysis for Geographers and Environmental Scientists , Neil Wrigley 相似文献
972.
Kick em Jenny submarine volcano, ~8 km north of Grenada, has erupted at least 12 times since it was first discovered in 1939, making it the most frequently active volcano in the Lesser Antilles arc. The volcano lies in shallow water close to significant population centres and directly beneath a major shipping route, and as a consequence an understanding of the eruptive behaviour and potential hazards at the volcano is critical. The most recent eruption at Kick em Jenny occurred on December 4 2001, and differed significantly from past eruptions in that it was preceded by an intensive volcanic earthquake swarm. In March 2002 a multi-beam bathymetric survey of the volcano and its surroundings was carried out by the NOAA ship Ronald H Brown. This survey provided detailed three-dimensional images of the volcano, revealing the detailed morphology of the summit area. The volcano is capped by a summit crater which is breached to the northeast and which varies in diameter from 300 to 370 m. The depth to the summit (highest point on the crater rim) is 185 m and the depth to the lowest point inside the crater is 264 m. No dome is present within the crater. The crater and summit region of Kick em Jenny are located at the top of an asymmetrical cone which is about 1300 m from top to bottom on its western side. It lies within what appear to be the remnants of a much larger arcuate collapse structure. An evaluation of the morphology, bathymetry and eruptive history of the volcano indicates that the threat of eruption-generated tsunamis is considerably lower than previously thought, mainly because the volcano is no longer thought to be growing towards the surface. Of more major and immediate concern are the direct hazards associated with the volcano, such as ballistic ejecta, water disturbances and lowered water density due to degassing. 相似文献
973.
Centrifuge modeling of PGD response of buried pipe 总被引:1,自引:1,他引:0
MichaelO'Rourke VikramGadicherla TarekAbdoun 《地震工程与工程振动(英文版)》2005,4(1):69-73
A new centrifuge based method for determining the response of continuous buried pipe to PGD is presented. The physical characteristics of the RPI‘s 100 g-ton geotechnical centrifuge and the current lifeline experiment split-box are described: The split-box contains the model pipeline and surrounding soil and is manufactured such that half can be offset, in flight, simulating PGD. In addition, governing similitude relations which allow one to determine the physical characteristics, (diameter, wall thickness and material modulus of elasticity) of the model pipeline are presented. Finally, recorded strains induced in two buried pipes with prototype diameters of 0.63 m and 0.95 m (24 and 36 inch) subject to 0.6 and 2.0 meters (2 and 6 feet) of full scale fault offsets and presented and compared to corresponding FE results. 相似文献
974.
A new integrated measuring system with eight force-balance accelerometers is proposed to obtain a direct measurement of six degree-of freedom (DOF) ground motions, including three rotational and three actual translational acceleration components without gyroscopes. In the proposed measuring system, the relationship between the output from eight force-balance accelerometer and the six DOF motion of the measuring system under an earthquake are described by differential equations. These equations are derived from the positions and directions of the eight force-balance accelerometers in the measuring system. The third-order Runge-Kutta algorithm is used to guarantee the accuracy of the numerical calculation. All the algorithms used to compute the six DOF components of the ground motion are implemented in a real-time in Digital Signal Processor (DSP). The distortion of the measured results caused by position and direction errors of the accelerometers in the measuring system are reduced by multiplying a compensation coefficient C to the output and subtracting static zero drift from the measured results, respectively. 相似文献
975.
This paper shows the results of a ground magnetic survey carried out to study solid waste landfills. The area located southward of Gualeguaychú town was chosen as a pilot case. This zone was selected considering the available knowledge about the cessation of operations, and the interest of the local authorities in verifying the existence of anomalies indicative of possible dangerous pollutants. The total magnetic field was measured along six profiles, and the corresponding anomalies were calculated. The profiles were modelled in 2.5 D, and along them Eulers deconvolution was used to estimate the depth to the sources. The first and the second derivatives of the residual magnetic field were calculated, in order to sharpen the anomalies. Our interpretation suggests that the characteristics of the modelled bodies and the magnitudes of the detected anomalies do not indicate the presence of drums in the sanitary infill. 相似文献
976.
N.?N.?AmbraseysEmail author J.?Douglas S.?K.?Sarma P.?M.?Smit 《Bulletin of Earthquake Engineering》2005,3(1):1-53
This article presents equations for the estimation of horizontal strong ground motions caused by shallow crustal earthquakes with magnitudes Mw 5 and distance to the surface projection of the fault less than 100km. These equations were derived by weighted regression analysis, used to remove observed magnitude-dependent variance, on a set of 595 strong-motion records recorded in Europe and the Middle East. Coefficients are included to model the effect of local site effects and faulting mechanism on the observed ground motions. The equations include coefficients to model the observed magnitude-dependent decay rate. The main findings of this study are that: short-period ground motions from small and moderate magnitude earthquakes decay faster than the commonly assumed 1/r, the average effect of differing faulting mechanisms is not large and corresponds to factors between 0.8 (normal and odd) and 1.3 (thrust) with respect to strike-slip motions and that the average long-period amplification caused by soft soil deposits is about 2.6 over those on rock sites. Disappointingly the standard deviations associated with the derived equations are not significantly lower than those found in previous studies. 相似文献
977.
An investigation of analysis of variance as a tool for exploring regional differences in strong ground motions 总被引:2,自引:1,他引:1
The statistical technique known as analysis of variance is applied to a large set of European strong-motion data to investigate whether strong ground motions show a regional dependence. This question is important when selecting strong-motion records for the derivation of ground motion prediction equations and also when choosing strong-motion records from one geographical region for design purposes in another. Five regions with much strong-motion data (the Caucasus region, central Italy, Friuli, Greece and south Iceland) are investigated here. For the magnitude and distance range where there are overlapping data from the five areas (2.50 Ms 5.50, 0 d 35 km) and consequently analysis of variance can be performed, there is little evidence for a regional dependence of ground motions. There is a lack of data from moderate and large magnitude earthquakes (Ms > 5.5) so analysis of variance cannot be performed there. Since there is uncertainty regarding scaling ground motions from small to large magnitudes whether ground motions from large earthquakes are significantly different in different parts of Europe is not known. Analysis of variance has the ability to complement other techniques for the assessment of regional dependence of ground motions. 相似文献
978.
Y.?BouhadadEmail author A.?Nour A.?Slimani N.?Laouami D.?Belhai 《Journal of Seismology》2004,8(4):497-506
A destructive earthquake of magnitude Mw = 6.8 hit the region of Boumerdes and Algiers (Algeria) on May 21, 2003. This is among the strongest seismic events of the mediterranean region and the most important event in the capital Algiers since 1716. It caused a widespread damage in the epicentral region, claimed 2271 human lives, injured 10000, about 20000 housing units affected and left about 160000 homeless. The main shock was felt about 250 km far from the epicenter and triggered sea waves of 1–3 m in amplitude in Balearic islands (Spain). Based on field observations and press report an intensity IX (MSK scale) is attributed to the epicentral area. The main shock was followed by many aftershocks among them several are of magnitude greater than 5.0, which added panic to inhabitants. The main shock triggered ground deformation, particularly liquefaction whose features are in different forms and sizes and caused damage and collapse of roads. The focal mechanism determined by worldwide institutions yield a pure reverse faulting with a compressional axis striking NE-SW. The epicenter is located offshore about 7 km from the Boumerdes-Dellys coast. Field observations show 0.7 m of coseismic uplift of shoreline between Boudouaou and Dellys. This uplift is about a half of the extracted coseismic slip from the seismic moment. On the other hand there is no clear surface break onshore, confirming hence, that the causative active fault is offshore. However, the rupture may propagate onshore to the SE near the Boudouaou region where ground cracks showing reverse faulting are observed a long a corridor of about 1 km wide. These fissures may correspond to a diffuse coseismic deformation. 相似文献
979.
Seismic ground motion relationship in southern China based on stochastic finite-fault model 总被引:1,自引:0,他引:1
The characteristics of seismic ground motions in southern China are difficult to determine statistically due to a lack of strong ground motion data. In this study, a stochastic finite-fault ground motion model was adopted to simulate the seismic ground motions at bedrock for southern China, based on parameters derived from small and medium earthquakes that have occurred in the region. From these, the response spectra was estimated. A set of ground motion attenuation relations hipswas then developed based on simulated peak ground motions and response spectral parameters through regression, which would be applicable for use in engineering practice. Through comparisons, it was demonstrated that the proposed ground motion relationships are generally consistent with those obtained from other reported ground motion attenuation models for southern China. 相似文献
980.
徐青 《测绘科学技术学报》2006,23(2):97-100
在对未来空间对抗的需求和测绘保障范围的拓展进行分析的基础上,提出了“数字空间”的构想和实施空间测绘(深空测绘)的发展思路;提出了“数字空间”的内涵和建立“数字空间”的技术与服务体系。“数字空间”建设应作为天空地一体数字化战场的核心内容,并为空间环境的认知与利用、控制空间以及空间目标的探测、识别、分类等技术手段提供全面的信息支撑。 相似文献