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981.
A primary goal of earthquake engineering is to protect society from the possible negative consequences of future earthquakes. Conventionally, this goal has been achieved indirectly by reducing seismic damage of the built environment through better building codes, or more comprehensibly, by minimizing seismic risk. However, the effect that building damage has on occupants is not explicitly taken into account while designing infrastructure. Consequently, this paper introduces a conceptual framework and numerical algorithm to assess earthquake risk on building occupants during seismic events, considering the evacuation process of the structure. The framework combines probabilistic seismic hazard analysis, inelastic structural response analysis and damage assessment, and couples these results with the response of evacuating agents. The results are cast as probability distributions of variables that measure the overall performance of the system (e.g., evacuation times, number of injured people, and repair costs) for specific time windows. As a testbed, the framework was applied to the response of a reinforced concrete frame building that exemplifies the use of all steps of the methodology. The results suggest that this seismic risk evaluation framework of structural systems that combine the response of a physical model with human agents can be extended to a wide variety of other situations, including the assessment of mitigation actions in communities and people to improve their earthquake resilience. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
982.
In the context of the current review of New Zealand's National Certificate of Educational Achievement (NCEA), the paper reflects on the nature and relevance of geography in education, life and work. The context of school geography programmes is critically examined, and a checklist of points for further consideration and action is presented. 相似文献
983.
984.
新西兰Taranaki盆地中新世Kora火山是海底喷发形成的碎屑岩型火山,可代表浅埋藏火山岩的储层特征.本文根据5口钻井的孔隙度、渗透率、孔隙孔径和铸体薄片开展Kora火山的储层特征、储集空间组成、缝宽以及原生和次生孔隙之间关系的分析.研究结果如下:(1)储集空间主要为次生孔隙,然后是裂缝和原生孔隙;Kora火山具有高... 相似文献
985.
A series of small-scale gravity induced synsedimentary faults are described from the Middle Coal Measures (Westphalian B) of the South Wales Coalfield. The synsedimentary nature of the faults is indicated by abrupt changes in sediment thickness across faults, eroded fault scarps and the restriction of faulting to 8·75 m of sediment bounded by laterally persistent black shales above and a seatearth below. Evidence for the non-tectonic origin of the faults is given by the presence of passive footwalls. Channel sandstone bodies occurring within the hanging walls of individual faults were deposited by discrete overbank flood events. Drainage patterns during flood events were controlled by topographic lows adjacent to the faults such that palaeocurrent data within the channel sandstone bodies indicate a S/SW transport direction parallel to fault strike. Synsedimentary fault movements resulted in the diagonal stacking of successively younger sandstone bodies adjacent to the faults, and an increase in tilt of the bodies with depth from 0 → 26°. The architecture of channel sandstone bodies was controlled by (1) the amount of fault movement and (2) fault block dimensions (or fault spacing). The interaction of these controlling factors resulted in deposition of symmetrical channel sandstone bodies over narrow fault blocks (12 m wide) with large fault displacements (7 m), asymmetrical sandstone bodies over wide fault blocks (30 m) with large fault displacement (7.5 m), and limited channel sandstone body development over fault blocks with small fault displacements (1.5 m). Synsedimentary faulting is thought to have been initiated by either seismic shock and/or overpressuring of pore fluids within buried mudstones. 相似文献
986.
George P. Kraemer Robert H. Chamberlain Peter H. Doering Alan D. Steinman M. Dennis Hanisak 《Estuaries and Coasts》1999,22(1):138-148
Fluctuations in freshwater input may affect the physiology and survival of submerged aquatic vegetation (SAV) occurring in oligoaline to mesohaline estuarine regions. Controls on the distribution of the freshwater angiosperm Vallisneria americana, were investigated by transplanting ramets. Pots (3.8-1) containing ramets were distributed among four sites (upstream site [least saline], donor site, near downstream site, and far downstream site [most saline]) in the Caloosahatchee Estuary (Southwest Florida) during wet (May–August) and dry (October–February) seasons. During 2–4 mo of each season, physiological indicators were monitored, including photosynthesis, glutamine synthetase activity, and protein content in shoots, and carbohydrates and total nitrogen and carbon in shoot and subterranean tissues. Where the physical environment (light or salinity) was suboptimal, all physiological indices, except photosynthetic rate, showed similar stress responses, which ranged from a slow decline to a rapid drop in physiological function. Levels of soluble carbohydrates decreased in response to unfavorable conditions more rapidly than did insoluble carbohydrates. Shoot protein of V. americana declined prior to transplant death, suggesting that measuring protein content may provide a rapid assessment of physiological health. V. americana transplants at the low-salinity upstream site died during both wet and dry season experiments, likely in response to light limitation and/or partial burial by sediments. At the far downstream site, death occurred within 2–4 wk, and was attributable to elevated salinities (>ca. 15‰). Comparison of physiological responses with salinity and light regimes at the donor and near downstream sites suggest that light may ameliorate salinity stress. This study demonstrates that V. americana, nominally classed as a freshwater macrophyte, is capable of a remarkable degree of halotolerance. 相似文献
987.
Alan Latham 《Area》1999,31(2):161-168
Summary This paper explores the dynamics of engagement and disengagement within urban space. It argues that a certain capacity to encounter the world around the self in an active, creative way is central to the self's ability to recognize and care about the places it inhabits and the people encountered within those places. Drawing on the work of Donald Winnicott and Jessica Benjamin, it outlines a framework of self-other psycho-dynamics through which this active, creative encountering may be understood, and examines the violence of indifference that occurs when this everyday creativity is absent. 相似文献
988.
989.
Alan F. Arbogast 《The Professional geographer》2000,52(4):594-606
The Nodaway dune field is perched along Lake Superior in Upper Michigan. This study uses absolute and relative‐age dating methods to test the hypothesis that the dune field finally stabilized after the Nipissing high stand, about 4,000 years ago. Surface soils on snouts of all dunes are moderately developed Spodosols, indicating that dunes stabilized within a few hundred years of each other. One thermoluminescence date provided an age of 8 ka from soil parent material, but is probably overestimated due to residual thermoluminescence. Subsequent optical stimulated luminescence and accelerator mass spectrometry age estimates indicate that the most recent accumulation of sand occurred between ?3.7 and 3.0 ka. This interval suggests one of three possibilities: 1) that the dune field was reactivated during the Algoma high stand and then stabilized; 2) that the dune field stabilized gradually, probably as sand supply diminished after the Nipissing high stand; and 3) that a combination of these two processes occurred. 相似文献
990.