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241.
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BOOK REVIEWS     
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   
243.
锦屏电站坝厂区卸荷岩体力学参数研究   总被引:4,自引:0,他引:4  
选择具有代表性的区块,根据结构面的性状和规模拟定模型层次和尺寸,建立岩体数值仿真模型,通过计算机数值仿真,采用卸荷非线性力学理论对锦屏电站坝厂区岩体进行卸荷岩体宏观力学特性及参数的数值分析;同时,用RMR法和BP神经网络法对岩体宏观力学特性及参数进行分析,综合确定岩体力学参数,为设计部门提供设计参考依据.  相似文献   
244.
《The Journal of geography》2012,111(4):211-212
Abstract

This article advocates that geography teachers undertake field studies of human systems with their students. A field trip process is described that helps teachers to guide students to explore and analyze a real human system with the expressed goal of building skills that can transfer to and complement a wide range of geographic learning tasks identified in Geography for Life: National Geography Standards 1994. Students are taken to a human system, such as a supermarket or a hotel. In groups, students interview as well as tour with a representative of a key department of the human system. Using teacher-supplied materials, groups create models or visual schematics of the whole human system they studied. The model must show the complex as a collection of interdependent elements with distinct functions. The learning outcomes achieved by students are a collection of geographic skills ideal for transfer to subsequent geographic investigations of urban places and or regions.  相似文献   
245.
旅游规划设计的内涵本质与核心理论研究   总被引:1,自引:0,他引:1  
随着旅游业在吸纳就业、调整产业结构、带动区域经济发展等诸多方面作用日益凸显,旅游规划市场呈现出蓬勃发展的趋势.然而,从学科来看旅游规划不仅缺乏独有的核心理论和关键技术作为支撑,而且其与其他规划设计在本质上的区别也尚未能予以清晰地界定.为此,在前人研究和多年规划实践基础上,就若干基础性问题进行探讨:一是提出了旅游规划设计的六大本质特征;二是提出了旅游规划设计师的四大看家本领;三是提出了旅游规划设计的“12345”核心理论框架;四是提出了旅游规划设计的综合诊断技术、创造体验技术、综合匹配技术、时空设计技术和综合集成技术五大关键技术方法;五是讨论了旅游规划设计的学科性质和地位.  相似文献   
246.
Extreme temperature events are simulated by using the Beijing Climate Center Atmospheric General Circulation Model (BCC AGCM) in this paper. The model has been run for 136 yr with the observed external forcing data including solar insolation, greenhouse gases, and monthly sea surface temperature (SST). The daily maximum and minimum temperatures are simulated by the model, and 16 indices representing various extreme temperature events are calculated based on these two variables. The results show that the maximum of daily maximum temperature (TXX), maximum of daily minimum (TNX), minimum of daily maximum (TXN), minimum of daily minimum (TNN), warm days (TX90p), warm nights (TN90p), summer days (SU25), tropical nights (TR20), and warm spell duration index (WSDI) have increasing trends during the 20th century in most regions of the world, while the cold days (TX10p), cold nights (TN10p), and cold spell duration index (CSDI) have decreasing trends. The probability density function (PDF) of warm/cold days/nights for three periods of 1881-1950, 1951- 1978, and 1979-2003 is examined. It is found that before 1950, the cold day/night has the largest probability, while for the period of 1979-2003, it has the smallest probability. In contrast to the decreasing trend of cold days/nights, the PDF of warm days/nights exhibits an opposite trend. In addition, the frost days (FD) and ice days (ID) have decreasing trends, the growing season has lengthened, and the diurnal temperature range is getting smaller during the 20th century. A comparison of the above extreme temperature indices between the model output and NCEP data (taken as observation) for 1948-2000 indicates that the mean values and the trends of the simulated indices are close to the observations, and overall there is a high correlation between the simulated indices and the observations. But the simulated trends of FD, ID, growing season length, and diurnal temperature range are not consistent with the observations and their correlations are low or even negative. This indicates that the model is incapable to simulate these four indices although it has captured most indices of the extreme temperature events.  相似文献   
247.
盛夏渤海湾大气边界层辐合线触发对流风暴对比分析   总被引:2,自引:2,他引:0  
赵金霞  徐灵芝  卢焕珍  范苏丹 《气象》2012,38(3):336-343
本文对渤海湾2008—2009年,由大气边界层辐合线引起的对流风暴进行了分析。结果表明,在高温、高湿不稳定大气层结环境条件下:(1)单一的海风锋在其端点可产生对流性降水。(2)海风锋与弱冷锋相遇,或者两条海风锋相交,或者雷暴单体的出流边界与海风锋相遇均会产生强对流风暴。(3)渤海湾边界层辐合线触发对流风暴大多发生在每年7 8月,且在副热带高压控制渤海湾后东退的过程中,此时大气层结处在高温、高湿不稳定状态。辐合线触发的对流风暴是沿辐合线移动,移动方向取决于辐合线两侧的主导风向。(4)边界层辐合线触发对流风暴,具有突发性强,持续时间短等特点,分析渤海湾边界层辐合线的移动与演变能提高强对流风暴的临近预报、预警,减少突发性天气引起的灾害。  相似文献   
248.
北大西洋涛动位相转换的数值研究   总被引:1,自引:0,他引:1  
李忠燕  罗德海 《大气科学》2012,36(2):374-384
借助一个非线性准地转正压模型,模拟了基本西风气流的强弱、不同空间分布的天气尺度扰动涡对北大西洋涛动(NAO)位相转换的作用,以及大尺度双波地形对其的影响.通过一系列的对比试验发现,适当弱的基本西风气流有利于下游系统西退使NAO由正(负)位相转换为负(正)位相;振幅强、活动范围大的天气尺度扰动波是NAO由负位相转换为正位...  相似文献   
249.
The influence of urban intensity on fog evolution in the Beijing-Tianjin-Hebei (BTH) region (China) is investigated numerically with the the Weather Research and Forecasting (WRF) model coupled with the urban canopy parameterization-building energy model (UCP- BEM) urban physics scheme. The experiments were designed with a focus on the influence of different urban intensities, which are represented by a different fractional coverage of natural land, buildings, and energy consumption inside buildings in an urban environment. The results of this study indicate that urban areas notably influence fog evolution when natural land is reduced to a small fraction (e.g., less than 10%). Developed land changes fog evolution through urban effects. Higher urban intensity (HUI) generally results in warmer temperatures and lower wind speeds throughout the day, while inhibiting morning specific humidity loss and afternoon specific humidity gain because of the HUI effect on surface heat flux, surface roughness, and surface moisture flux. HUI leads to later and weaker liquid water content formation, with a higher liquid water content base, primarily due to its effect on near surface temperatures. This finding implies that HUI may inhibit the conditions for fog formation. In addition, urban areas with equal natural and developed land coverage seem to greatly enhance the upward surface moisture flux, which is attributed to the combination of a relatively large potential evaporation on developed land and an ample moisture supply from natural land. As a result, the specific humidity increases in the afternoon.  相似文献   
250.
The performance of BCC (Beijing Climate Center) AGCM 2.0.1 (Atmospheric General Circulation Model version 2.0.1) in simulating the tropical intraseasonal oscillation (TIO) is examined in this paper.The simulations are validated against observation and compared with the NCAR CAM3 (Community Atmosphere Model version 3) results.The BCC AGCM2.0.1 is developed based on the original BCC AGCM (version 1) and NCAR CAM3.New reference atmosphere and reference pressure are introduced into the model.Therefore,the origi...  相似文献   
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