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571.
The main objectives of this study were (1) to examine what has beenrecovered and what has not yet been recovered in Nishinomiya City five years after the GreatHanshin-Awaji Earthquake, and (2) to find current service needs for the earthquake survivors,especially for the disadvantaged populations. Disadvantaged populations are minorities in society, andtheir needs and opinions are often ignored and not reflected in the services or mitigation policy,despite the fact that they are the ones who are affected most by various hazards. At the same time, becauseof their unique characteristics and positions in society, their needs differ from the majorityof the society. Six hundred eighty-six opinion cards were collected in nine grassroots workshopsessions with various disadvantaged groups in Nishinomiya City, such as the physically challenged,the visually impaired, the elderly living in public housing, junior and senior high school students,mothers with small children, and those who lost their own homes because of the earthquake. Theseopinion cards were sorted out and analyzed by using a TQM(Total Quality Management)-basedassessment method. Since the TQM-based assessment method allows bottom-up integration ofopinions from each individual, it helps us identify unique needs of the disadvantaged groupsand reflect their opinions in mitigation plan and policies. The main findings of this study include (1)the city redevelopment cannot be achieved without integrating the viewpoints of thedisadvantaged; (2) the social support was a key resource for both mental health and community development;and (3) disaster experiences and adaptation produced civic mindedness among people in a community. 相似文献
572.
Cities’ ability reducing earthquake disasters is a complex system involving numerous factors, moreover the research on evaluating
cities’ ability reducing earthquake disasters relates to multi-subject, such as earthquake science, social science, economical
science and so on. In this paper, firstly, the conception of cities’ ability reducing earthquake disasters is presented, and
the ability could be evaluated with three basic elements — the possible seismic casualty and economic loss during the future
earthquakes that are likely to occur in the city and its surroundings and time required for recovery after earthquake; based
upon these three basic elements, a framework, which consists of six main components, for evaluating city’s ability reducing
earthquake disasters is proposed; then the statistical relations between the index system and the ratio of seismic casualty,
the ratio of economic loss and recovery time are gained utilizing the cities’ prediction results of earthquake disasters which
were made during the ninth five-year plan; at last, the method defining the comprehensive index of cities’ ability reducing
earthquake disasters is presented. Thus the relatively comprehensive theory frame is set up. The frame can evaluate cities’
ability reducing earthquake disasters absolutely and quantitatively and consequently instruct the decision-making on reducing
cities’ earthquake disasters loss.
Foundation item: State Important Research Project of China (95130603). 相似文献
573.
574.
Wu Ji Li Dihui Zhang Xiaohui Jiang Jingshan A. T. Altyntsev B. I. Lubyshev 《Journal of Earth System Science》2005,114(6):627-632
Among many scientific objectives of lunar exploration, investigations on lunar soil become attractive due to the existence
of He3 and ilmenite in the lunar soil and their possible utilization as nuclear fuel for power generation. Although the composition
of the lunar surface soil can be determined by optical and γ/X-ray spectrometers, etc., the evaluation of the total reserves
of He3 and ilmenite within the regolith and in the lunar interior are still not available. In this paper, we give a rough analysis
of the microwave brightness temperature images of the lunar disc observed using the NRAO 12 meter Telescope and Siberian Solar
Radio Telescope. We also present the results of the microwave dielectric properties of terrestrial analogues of lunar soil
and, discuss some basic relations between the microwave brightness temperature and lunar soil properties. 相似文献
575.
H. Mizutani A. Fujimura S. Tanaka H. Shiraishi T. Nakjima 《Journal of Earth System Science》2005,114(6):763-768
The scientific objective of the Lunar-A, Japanese Penetrator Mission, is to explore the lunar interior by seismic and heat-flow
experiments. Two penetrators containing two seismometers (horizontal and vertical components) and heat-flow probes will be
deployed from a spacecraft onto the lunar surface, one on the near-side and the other on the far-side of the moon. The data
obtained by the penetrators will be transmitted to the earth station via the Lunar-A mother spacecraft orbiting at an altitude
of about 200 km.
The spacecraft of a cylindrical shape, 2.2 m in maximum diameter and 1.7 m in height, is designed to be spin-stabilized. The
spacecraft will be inserted into an elliptic lunar orbit, after about a half-year cruise during which complex manoeuvering
is made using the lunar-solar gravity assist. After lunar orbit insertion, two penetrators will be separated from the spacecraft
near perilune, one by one, and will be landed on the lunar surface.
The final impact velocity of the penetrator will be about 285 m/sec; it will encounter a shock of about 8000 G at impact on
the lunar surface. According to numerous experimental impact tests using model penetrators and a lunar-regolith analog target,
each penetrator is predicted to penetrate to a depth between l and 3 m, depending on the hardness and/or particle-size distribution
of the lunar regolith. The penetration depth is important for ensuring the temperature stability of the instruments in the
penetrator and heat flow measurements. According to the results of the Apollo heat flow experiment, an insulating regolith
blanket of only 30 cm is sufficient to dampen out about 280 K lunar surface temperature fluctuation to < 3 K variation.
The seismic observations are expected to provide key data on the size of the lunar core, as well as data on deep lunar mantle
structure. The heat flow measurements at two penetrator-landing sites will also provide important data on the thermal structure
and bulk concentrations of heat-generating elements in the Moon. These data will provide much stronger geophysical constraints
on the origin and evolution of the Moon than has been obtained so far.
Currently, the Lunar-A system is being reviewed and a more robust system for communication between the penetrators and spacecraft
is being implemented according to the lessons learned from Beagle-2 and DS-2 failures. More impact tests for penetrators onto
a lunar regolith analogue target will be undertaken before its launch. 相似文献
576.
Unique recovery stage of reef communities after F/F event in a huge coral reef of Carboniferous, Southern Guizhou,China 总被引:7,自引:0,他引:7
GONG Enpu YANG Hongying GUAN Changqing SUN Baoliang & YAO Yuzeng Department of Geology Northeastern University Shenyang China 《中国科学D辑(英文版)》2004,47(5)
Carboniferous is a global recession period of reef-building. There were fewer reefs at that times due to massive extinction and the great glacial catastrophe in the southern hemisphere in Frasnian/Famennian[1]. So far, however, most of the researches concerning Carboniferous reefs have been limited, which leads to insufficient knowledge regarding the composition, structure, ecological characteristics of reef-building communities, the reef growth models, etc. Interna-tional studies conducted o… 相似文献
577.
变质程度达角闪岩相及麻粒岩相的各类变质岩石在变质作用高峰期后,如果降温速率比较慢,往往发生退变质性质的离子再交换反应与纯转换反应。这两类退变质反应不可避免地改造了变质高峰期的矿物成分,使岩石不能准确记录变质作用各阶段的矿物成分和变质作用p-T轨迹。对这两类反应的研究已成为近年来变质岩石学研究的热点之一。本文通过研究实例,简要综述了基性麻粒岩中石榴子石-斜方辉石之间的Fe-Mg再交换反应、酸性麻粒岩中斜长石-碱性长石之间的K-Na再交换反应、泥质片麻岩中石榴子石变斑晶边部的部分分解(纯转换)反应,以及恢复变质高峰期矿物成分和计算变质高峰期p-T条件的方法。指出只有在准确恢复变质高峰期变质矿物成分的基础上,获得的变质作用p-T-t轨迹才能反映客观地质事实。 相似文献
578.
Numerical modelling of flow structures over idealized transverse aeolian dunes of varying geometry 总被引:2,自引:0,他引:2
A Computational Fluid Dynamics (CFD) model (PHOENICS™ 3.5) previously validated for wind tunnel measurements is used to simulate the streamwise and vertical velocity flow fields over idealized transverse dunes of varying height (h) and stoss slope basal length (L). The model accurately reproduced patterns of: flow deceleration at the dune toe; stoss flow acceleration; vertical lift in the crest region; lee-side flow separation, re-attachment and reversal; and flow recovery distance. Results indicate that the flow field over transverse dunes is particularly sensitive to changes in dune height, with an increase in height resulting in flow deceleration at the toe, streamwise acceleration and vertical lift at the crest, and an increase in the extent of, and strength of reversed flows within, the lee-side separation cell. In general, the length of the separation zone varied from 3 to 15 h from the crest and increased over taller, steeper dunes. Similarly, the flow recovery distance ranged from 45 to >75 h and was more sensitive to changes in dune height. For the range of dune shapes investigated in this study, the differing effects of height and stoss slope length raise questions regarding the applicability of dune aspect ratio as a parameter for explaining airflow over transverse dunes. Evidence is also provided to support existing research on: streamline curvature and the maintenance of sand transport in the toe region; vertical lift in the crest region and its effect on grainfall delivery; relations between the turbulent shear layer and downward forcing of flow re-attachment; and extended flow recovery distances beyond the separation cell. Field validation is required to test these findings in natural settings. Future applications of the model will characterize turbulence and shear stress fields, examine the effects of more complex isolated dune forms and investigate flow over multiple dunes. 相似文献
579.
580.
南水北调引水进京后北京市地下水环境预测 总被引:1,自引:0,他引:1
本文通过对受水区的地下水水位、水质变化预测,分析了北京市区的地下水环境变化情况,提出了调水工程实施后将会产生的主要环境地质问题。并结合地下水环境修复、生态恢复、地质环境问题防治等实际需要,进行了地下水停采方案的分析,为北京市未来水资源调配、地下水环境保护、城市规划修编提供依据。 相似文献