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151.
152.
MIAO Qingsheng YUE Xinyang YANG Jinkun WANG Zhifeng XU Shanshan YANG Yang CHU Siqi 《中国海洋大学学报(英文版)》2022,21(2):315-322
Extreme water levels are related to astronomical tides and storm surges.Eleven typhoon systems,which have caused extreme water level rises,were selected based on 60-yr water level data from the Xiamen tide gauge station.In these 11 typhoon systems,the astronomical tide component accounts for 71%-95%of the total water level.The Gumbel distribution of extreme water level rise was estimated,and the impact of typhoon surges on water levels during the return period was analyzed.The ex-treme tide levels caused by typhoons Herb(1996)and Dujuan(2015)are much higher than those of other typhoons and correspond to the return period of 76 yr and 71 yr,respectively.The differences of sea levels in the presence and absence of these two typhoons in the 10-100 yr return period are 5.8-11.1 cm.For the 100-yr return period,the total risks within 10,25,50,and 100 yr increase by 94.3%,85.4%,72.9%,and 54.4%,respectively,if the Herb and Dujuan are not considered.Assuming that typhoon Herb(1996)occurred during the highest astronomical tide,it will produce a water level higher than that of the 1000-yr return period.Sea level rise has an important influence on the water level return period,and the contribution of nonlinear sea level rise in the next 100 yr is estimated to be 10.34%. 相似文献
153.
GIS in the K-12 Curriculum: A Cautionary Note 总被引:7,自引:0,他引:7
Judith W. Meyer Jon Butterick Michael Olkin George Zack 《The Professional geographer》1999,51(4):571-578
Two qualitative case studies, one focusing on K-12 teachers and the other on middle school students, explore key factors associated with using Geographic Information Systems in the classroom. In both studies, access to appropriate hardware is a critical barrier. Time is another critical barrier—time to learn the GIS software and time in the curriculum to incorporate GIS as a learning experience. In both case studies, learning the technology at the expense of learning spatial analysis was a danger, suggesting the need for conscious focus on the goal of using GIS to learn how to “do geography.” 相似文献
154.
《The Professional geographer》1999,51(4):610-620
Books reviewed: Robert W. Christopherson (ed.) Elemental Geosystems Gertjan Dijkink National Identity and Geopolitical Visions: Maps of Price and Pain David Farrell Krell Architecture: Ecstasies of Space, Time and the Human Body Victor L. Mote Siberia: Worlds Apart Richard Pillsbury No Foreign Food: The American Diet in Time and Place Grant R. Staff Changing Cape Town: Urban Dynamics, Policy, and Planning During the Political Transition in South Africa David Briggs, Peter Smithson, Kenneth Addison, and Ken Atkinson Fundamentals of the Physical Environment H.J. DeBlij and Peter O. Miller Physical Geography of the Global Environment Chris Park The Environment: Principles and Applications Alan Strahler and Arthur Strahler Introducing Physical Geography 相似文献
155.
The Tycho Epoch Photometry Annex A, a data base of photometry of more than 34 000 bright stars, has been searched for periodic variable stars with approximately sinusoidal light curves. Advantage was taken of special properties of the observing programme (photometry in two wavebands, availability of repeated measurements) to use simple but efficient variable selection criteria. Details of 70 strong candidate variables are presented. 相似文献
156.
主动光学─新一代大望远镜的关键技术 总被引:1,自引:0,他引:1
对主动光学技术在现代天文光学望远镜中的作用和工作原理作了较全面的介绍和评论。结合作者近十年的工作对薄镜面主动光学技术和拼接镜面主动光学技术的各个关键部分,如波前检测、波前拟合、校正力的确定、共焦和共面的检测作了较详细且深入的讨论和评述.也介绍了我国目前正在研制的同时采用薄镜面主动光学和拼接镜面主动光学技术的大天区面积多目标光纤光谱望远镜的主动光学系统。 相似文献
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158.
介绍云南天文台CCD检测实验室检测天文用CCD系统的方法,检测参数主要包括:线性、噪声、增益、量子效率以及转移效率等. 相似文献
159.
Higher education in England has expanded rapidly in the last ten years with the result that currently more than 30% of young
people go on to university. Expansion is likely to continue following the recommendations of a national committee of inquiry
(the Dearing Committee). The participation rate is known to vary substantially among social groups and between geographical
areas. In this paper the participation rate is calculated using a new measure, the Young Entrants Index (YEI), and the extent
of variation by region, gender and residential neighbourhood type established. The Super Profiles geodemographic system is
used to facilitate the latter. This is shown to be a powerful discriminator and to offer great potential as an alternative
analytical approach to the conventional social class categories, based on parental occupation, that have formed the basis
of most participation studies to date.
Received: 20 October 1998/Accepted: 5 May 1999 相似文献
160.