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921.
有关单位制度与生活圈的讨论多数集中在具有较长计划经济历史与较强国有经济色彩的城市,但是实际上一些新兴城市也存在单位制度实践或类似制度实践.以深圳为例,论文在分析了深圳城市建设与发展过程中的单位制度力量后,选取7个具有单位社区特征的社区,对比商品房社区与城中村社区,从空间行为和社会关系等维度描绘了这些社区居民生活圈的特征...  相似文献   
922.
一种基于时差的地震救助生命定位方法   总被引:2,自引:0,他引:2  
参照经典的地震定位方法Geiger法,提出了一种在地震救助中很实用的基于振动直达波到达时差的定位方法,通过模拟实验和计算,验证了该方法的可行性。  相似文献   
923.
BOOK REVIEWS     
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   
924.
基于现场实测风机桥架振动响应,采用风机调幅扰力模型进行结构动力响应分析.根据不同工况下疲劳危险点的名义应力时程,采用雨流计数法和各工况年运行频次调查结果编制疲劳载荷谱.通过Miner损伤累积准则和p-S-N关系对风机桥架进行疲劳损伤分析,给定疲劳破坏的损伤阈值,所得疲劳寿命满足设计使用年限的要求.采用Goodman、Gerber和Soderberg模型考虑平均应力影响时的疲劳寿命略有降低.  相似文献   
925.
INTRODUCTIONNoctilucascintillanshastwotypesofcelldivisions:vegetativedivisionandmeioticprocess.Inthemeioticprocess,thecelldividesseveraltimeswithoutcytoplasmicdivision .Afterthenucleardi visions,upto 2 10 zoosporesareformedfromonemothercell.Thesignificanceo…  相似文献   
926.
927.
白兴兰  姚锐  段梦兰  李强 《海洋工程》2014,32(5):107-112
与海床的相互作用是钢悬链线立管特有的性质,是传统立管发展中不曾遇到的问题,也是控制立管疲劳寿命的主要因素,特别是触地区出现的峰值弯曲应力和管土接触模型的不确定,成为SCR触地区研究的难点。由于立管与海床的作用机理非常复杂,因此管土相互作用模型的提出大多是建立在模型试验的基础上。通过对国内外深水SCR触地区管土相互作用试验研究案例的分析,简要介绍了SCR触地点的动态响应取决于一系列参数,如海床土刚度、加载状况、立管的提升速度、土的重塑时间和土吸力等,并设计了一套三维管-土相互作用的试验装置,能够为深水钢悬链线立管触地区管-土相互作用的试验研究提供参考。  相似文献   
928.
The marine environment provides a number of services which contribute to human well-being including the provision of food, regulation of climate and the provision of settings for cultural gains. To ensure these services continue to be provided, effective management is required and is being strategically implemented through the development of marine spatial plans. These plans require an understanding of the costs and benefits associated with alternative marine uses and how they contribute to human well-being. One benefit which is often difficult to quantify is the health benefit of engaging with the marine environment. To address this, the research develops an approach which can estimate the contribution aquatic physical activities makes to quality adjusted life years (QALYs) in monetary and non-monetary terms. Using data from the Health Survey for England, the research estimates that physical activities undertaken in aquatic environments at a national level provides a total gain of 24,853 QALYs. A conservative estimate of the monetary value of a QALY gain of this magnitude is £176 million. This approach provides estimates of health benefits which can be used in more comprehensive impact assessments, such as cost-benefit analysis, to compare alternative marine spatial plans. The paper concludes by discussing future steps.  相似文献   
929.
Seventeen infaunal benthic communities are recognised from sampling on the New Zealand continental shelf and upper continental slope. These are characterised in terms of geographic distribution, substrate and bathymetric range, and commoner infaunal bivalves and echinoderms.  相似文献   
930.
The size and age structures, sex ratio, size- and age-at-sex-change, growth and mortality rate of the protogynous hermaphrodite, steentjie Spondyliosoma emarginatum, were compared to determine the effects on population structure and life-history parameters of exploitation (comparing an unexploited reserve and an exploited area in Langebaan Lagoon) and biogeography (comparing Langebaan Lagoon and Struisbaai on the south-west coast of South Africa). There were few large fish and a sex ratio skewed towards relatively more females in the exploited area compared with the reserve in Langebaan. The age structure of female steentjies was truncated in the exploited area but the male age structure was unaffected, possibly because of the poor relationship between size and age of males caused by accelerated growth-at-sex-change. There were no differences in the size- and age-at-sex-change between the reserve and the exploited area, suggesting that steentjies have not shown a physiological response to exploitation in Langebaan and are unable to compensate for a skewed sex ratio. The comparison between Struisbaai and Langebaan showed that the growth rate of steentjies in Struisbaai was slower and the size-at-sex-change smaller than those at Langebaan. Linefish stock assessments may have to account for regional differences in physiological parameters.  相似文献   
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