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271.
This discussion deals with recommendations in the paper on appropriate damping formulations for use in nonlinear response history analysis of buildings. Concern over potentially excessive damping forces and moments should extend beyond the damping moments produced by the stiffness proportional part of Rayleigh damping that corresponds to rotational springs used to explicitly model plastic hinges. The key to an appropriate damping formulation for nonlinear analysis is a realistic mechanism that allows all damping forces and moments to be meaningfully assessed. Then features can be added to keep these forces and moments within reasonable bounds. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
272.
刘博  朱竑 《热带地理》2016,36(2):174-180
全球化使品牌与地方之间的联系日益密切。西方国家的快时尚品牌实行全球同价、全球同款和标准化的经营模式,被认为具有消极的品牌形象,然而却在异源文化背景的中国实现品牌升级。以ZARA为例,从时间和空间2个维度出发,描述其品牌空间发展史,分析品牌源地、空间发展、店铺选址等参与快时尚品牌的文化生产过程。结论如下:1)快时尚品牌与全球时尚城市建立积极联系,将全球时尚城市想象写入品牌发展史中,品牌空间发展史比品牌源地对品牌形象的影响更大;2)ZARA与全球时尚城市互动成功塑造全球时尚品牌形象,“全球”品牌头衔对于中国本土向往全球化的消费者来说具有很强的吸引力,对于其跨国升级有积极影响;3)ZARA在中国大陆的品牌空间发展依然延续“下沉式”模式,利用上海、北京、深圳、广州等地在全国时尚产业中的引领地位影响二级城市消费者的品牌选择,实现其跨国品牌升级;4)专卖店选址于高端消费街区,在跨国过程中重新定位于中高端消费群体,使得ZARA实现跨国品牌升级。  相似文献   
273.
蒋志荣  罗显辉 《云南地质》2009,28(3):259-262
锑矿化集中于喜马拉雅期石英斑岩内接触带,存在矿源层形成、充分分异及近地表成矿三个阶段。可作为滇西碱性岩锡矿床典型。  相似文献   
274.
地质年代学发展历史的简要回顾及前景   总被引:1,自引:0,他引:1  
陈宣华  董树文  史静 《世界地质》2009,28(3):384-396
简要介绍了基于矿物封闭温度的地质热年代学, 并对多种地质年代学方法, 包括U-Pb 法、 Sm-Nd法、Rb-Sr法、Lu-Hf法、Re-Os法、40Ar /39Ar法、裂变径迹( FT) 测年、(U-Th) /He法、 TIMS铀系法、宇宙成因核素定年(包括14C法等) 和年轻地下水测年(如3H /3He法等) 进行了综合评述。探讨了国际地质年代学百年来和中国20世纪80年代中期以来的发展趋势。根据近期使用情况分析, 认为U - Pb法、40Ar /39Ar法和14C法是目前使用较多的可靠测年方法。应用于山脉隆升和地貌形成的低温热年代学方法及地下水等年轻地质体系的测年, 将是地质年代学发展的重要方向。  相似文献   
275.
Data from in situ piezocone tests (CPTU) and laboratory analyses are utilized for the interpretation of the stress history of Quaternary sedimentary sequences in the upper continental slope of the Gulf of Lion, northwestern Mediterranean Sea. A CPTU based preconsolidation pressure profile referenced to the current effective stress indicates that the deposit is underconsolidated from 12 meters below the seafloor (mbsf) down to at least 150 mbsf. Excess pore pressure below 12 mbsf is further supported by results from oedometer and dissipation tests. Subseafloor pockmarks and indications of free gas in seismic reflection profiles reveal four main overpressure sources (SI–SIV) with overpressure ratios >0.3 at subseafloor depths coinciding with levels where the dominantly silty-clayey sediment contains increased proportions of sand. We relate the excess pore pressure related to free gas due to gas exsolution processes and sea level variations driven by Pleistocene sea level changes.  相似文献   
276.
Abstract

Most traditional segregation measures, such as the index of dissimilarity D, fail to distinguish spatial patterns effectively. Previously proposed spatial measures modifying D suffer from several shortcomings. This article describes a general spatial segregation index based upon the concept of composite population counts, which are derived from grouping people in neighboring areas together to account implicitly for spatial interaction of groups across unit boundaries. The suggested spatial index can overcome the disadvantages of previous indices and can assess the spatial extent of the segregated clusters. The results offer a more comprehensive depiction of spatial segregation of a region.

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277.
278.
Books reviewed:

Bassin, Mark, Imperial Visions: Nationalist Imagination and Geographical Expansion in the Russian Far East, 1840 – 1865

Shortridge, James R., Our Town on the Plains: J. J. Pennell's Photographs of Junction City, Kansas, 1893 – 1922

Jakle, John A. and Sculle, Keith A., Fast Food: Roadside Restaurants in the Automobile Age

Boeschenstein, Walter, Historic American Towns along the Atlantic Coast

McKee, Jesse O., Ethnicity in Contemporary America: A Geographical Appraisal

Luciuk, Lubomyr Y., Searching for Place: Ukrainian Displaced Persons, Ottawa, and the Migration of Memory

Hausladen, Gary, Places for Dead Bodies

Phillips, Richard, Watt, Diane and Shuttleton, David, De-Centering Sexualities: Politics and Representations beyond the Metropolis

Goldin, Liliana R., Identities on the Move, Transnational Processes in North America and the Caribbean Basin

McDonald, David A., On Borders: Perspectives on International Migration in Southern Africa

Fox, Roddy and Rowntree, Kate, The Geography of South Africa in a Changing World

Takeuchi, Keiichi, Modern Japanese Geography: An Intellectual History

Amery, Hussein A., and Wolf, Aaron T., Water in the Middle East: A Geography of Peace

Karl, Thomas R., Nicholls, Neville and Ghazi, Anver, Weather and Climate Extremes: Changes, Variations, and a Perspective from the Insurance Industry

Pittman, Blair, Texas Caves  相似文献   
279.
280.
Recognized for years as a major environmental disruption, El Niño generated intense public interest in 1982–1983. During its last occurrence, this phenomenon, which develops in the tropical Pacific and usually affects rimlands of the Pacific basin, exceeded its boundaries and its effects were transmitted to continental North America, Europe, Africa and East Asia. Notwithstanding its vast areal extent, the interest of geographers in El Niño events, past and recent, has been comparatively less than that demonstrated by natural scientists and ecologists: little has been accomplished to place these climatic-ecological crises within global perspective. Lessons from El Niño include the acknowledgement of new concepts of climatic transitivity, ocean dynamics and energy exchanges that must find a place within the conceptual wealth of geography if this science intends to keep up with the rapid progress of other geosciences.  相似文献   
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