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141.
1 Background of the new national seismic zoning map The policy of seismic disaster mitigation in the Chinese mainland is prevention first. According to the law, the earthquake design for ordinary structures must fit the demand of national seismic zoning map. Seismic zoning map is the basis of the earthquake design (TANG, 1998; WU, et al, 1998). The seismic zoning map must be updated with the progress in methodology and accumula-tion of the data. There are three generations of national seis…  相似文献   
142.
Freshwater and marine ecosystems are exposed to various multi-component mixtures of pollutants. Nevertheless, most ecotoxicological research and chemicals regulation focus on hazard and exposure assessment of individual substances only, the problem of chemical mixtures in the environment is ignored to a large extent. In contrast, the assessment of combination effects has a long tradition in pharmacology, where mixtures of chemicals are specifically designed to develop new products, e.g. human and veterinary drugs or agricultural and non-agricultural pesticides. In this area, two concepts are frequently used and are thought to describe fundamental relationships between single substance and mixture effects: Independent Action (Response Addition) and Concentration Addition. The question, to what extent these concepts may also be applied in an ecotoxicological and regulatory context may be considered a research topic of major importance, as the concepts would allow to make use of already existing single substance toxicity data for the predictive assessment of mixture toxicities. Two critical knowledge gaps are identified: (a) There is a lack of environmental realism, as a huge part of our current knowledge about the applicability of the concepts is restricted to artificial situations with respect to mixture composition or biological effect assessment. (b) The knowledge on what exactly is needed for using the concepts as tools for the predictive mixture toxicity assessment is insufficient. Both gaps seriously hamper the necessary, scientifically sound consideration of mixture toxicities in a regulatory context.In this paper, the two concepts will be briefly introduced, the necessity of considering the toxicities of chemical mixtures in the environment will be demonstrated and the applicability of Independent Action and Concentration Addition as tools for the prediction and assessment of mixture toxicities will be discussed. An overview of the specific aims and approaches of the BEAM project to fill in the identified knowledge gaps is given and first results are outlined.  相似文献   
143.
This paper illustrates the seismic risk preliminary estimates of two different groups of structures located on the territory of the Friuli–Venezia Giulia region (NE Italy) : the first group includes some special industrial plants, and the second group includes bridges and tunnels belonging to the regional highway network. The part of the study on special industrial plants tries to evaluate the degree of expected damage, taking into account their structural typology and ground shaking expressed in terms of macroseismic intensity. The second part of the study is an application of the HAZUS methodology to the tunnels and bridges of a highway network: the combination of expected ground shaking and the construction characteristics lead to very different risk levels, especially when considering the bridges. The resulting damage levels to bridges and tunnels are still only indicative because of the fragility curves used in the evaluations: they were developed for existing bridge and tunnel structural typologies in the U.S.A. Moreover, both examples show the power of GIS technology in storing, elaborating, and mapping spatial data. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
144.
This work presents a novel procedure for identifying the dynamic characteristics of a building and diagnosing whether the building has been damaged by earthquakes, using a back‐propagation neural network approach. The dynamic characteristics are directly evaluated from the weighting matrices of the neural network trained by observed acceleration responses and input base excitations. Whether the building is damaged under a large earthquake is assessed by comparing the modal parameters and responses for this large earthquake with those for a small earthquake that has not caused this building any damage. The feasibility of the approach is demonstrated through processing the dynamic responses of a five‐storey steel frame, subjected to different strengths of the Kobe earthquake, in shaking table tests. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
145.
Tsunamis have occurred in Canada due to earthquakes, landslides, and a large chemical explosion. The Pacific coast is at greatest risk from tsunamis because of the high incidence of earthquakes and landslides in that region. The most destructive historical tsunamis, however, have been in Atlantic Canada – one in 1917 in Halifax Harbour, which was triggered by a catastrophic explosion on a munitions ship, and another in 1929 in Newfoundland, caused by an earthquake-triggered landslide at the edge of the Grand Banks. The tsunami risk along Canada's Arctic coast and along the shores of the Great Lakes is low in comparison to that of the Pacific and Atlantic coasts. Public awareness of tsunami hazard and risk in Canada is low because destructive tsunamis are rare events.  相似文献   
146.
Ken Durham 《Natural Hazards》2003,30(2):251-261
Cairns is exposed to the well-known natural hazards oftropical cyclone, flood, stormsurge and thunderstorm, but is also exposed to thelesser-known hazards of landslip, earthquake and dam break flooding. Recommendations fortreating the risks associated with these hazards have been made that will involve amulti-disciplinary approach to treatment strategies, require the cooperation of allthree levels of government, involve public utility authorities and private enterprise andinvolve the community as a whole.This paper summarises the suggested mitigation treatmentoptions, presented to the Cairns City Council and identified in the LocalGovernment Disaster Mitigation Project conducted in Cairns in 1999/2000 by theQueensland Department of Emergency Services.  相似文献   
147.
Glacial Lake Outburst Floods in the Nepal Himalaya: A Manageable Hazard?   总被引:1,自引:0,他引:1  
Within the past fifteen years, glacial lake outburst floods have become an activetopic of discussion within the development community focused on Nepal. Suchfloods endanger thousands of people, hundreds of villages, and basic infrastructuresuch as trails and bridges. The flood risk is also a major impediment to hydroelectricdevelopment in several river basins. Unlike most other mountain hazards in Nepal,reducing the possibility of outburst floods is technically feasible. The first attemptwithin Nepal to reduce the hazard of one lake by artificially lowering its water levelwas partially completed in June 2000. Completing this task and beginning work onother hazardous lakes will require difficult decisions about risk by downstream residentsand substantial investment from the international aid community.  相似文献   
148.
Horie  Kei  Maki  Norio  Kohiyama  Masayuki  Lu  Hengjian  Tanaka  Satoshi  Hashitera  Shin  Shigekawa  Kishie  Hayashi  Haruo 《Natural Hazards》2003,29(3):341-370
Rebuilding of victims' livelihoods was a crucial issue in the restoration process in the1995 Hanshin-Awaji Earthquake Disaster. Housing damage assessment influencedmost of the rebuilding of the livelihood in the long term, because the Victim Certificatesissued by the local governments based on the results of the Housing damage assessmentwas required to receive most of the individual assistance measures. In the process ofHousing damage assessment, many complex problems arose, leading to extensivework on the part of the disaster responders. Consequently, a considerable number ofvictims were dissatisfied with the assessment and applied for a resurvey. Due to a floodof requests for resurvey, disaster responders had to work on damage assessment, leavingrelief activities aside.In order to facilitate Housing damage assessment, this paper discusses thefollowing five points: (1) the processes and the problems of assessments performedin the Hanshin-Awaji Earthquake Disaster, (2) the changes in the nature of informationneeded by the victims, (3) the improvements over the present damage assessment, (4)the housing situation in Japan, and (5) the international situation on damage assessment.It is obvious from the results that a poor damage assessment system and the size ofthe disaster produced a very large work load. Differences in appreciation among theinvestigators also contributed to unfair assessments and led to the victims beingincreasingly dissatisfied by the survey results. Finally, a design concept for acomprehensive damage assessment system, which has been derived from theabove five points, is proposed for post-disaster management.  相似文献   
149.
Quantifying Storm Tide Risk in Cairns   总被引:6,自引:5,他引:6  
The United Nations International Decade for Natural Disaster Reduction (IDNDR)gave rise to an increasing level of attention to the risks posed by a range of naturalhazards and the development of strategies by which to reduce those risks. It waswidely recognised that in order to evaluate risk treatment strategies it was necessaryto `measure' the level of risk that already existed and the level of risk that would beencountered with the treatment strategy(s) in place.This paper outlines the methodology developed under the AGSO (now GeoscienceAustralia) Cities Project to quantify the risk associated with storm tide inundation. It includes the methodology for `measuring' the level of community exposure to storm tide hazards and the methodology for `measuring' community vulnerability. The Far North Queensland city of Cairns is used as the case study to demonstrate the application of these methods.  相似文献   
150.
This paper is a partial discussion of a four-year study that investigated the vulnerability of the people living in the Cairns region to the tropical cyclone hazard. The longitudinal case study, focussing on the Cairns Northern Beaches area, was unique in that it included a social and societal `pre-cyclone impact' evaluation of various resident communities within the region, and then two consecutive `post-cyclone impact' studies. The primary research method supported an inductive qualitative approach to the collection and analysis of survey data. Some quantitative methods were invoked to support qualitative research findings. Survey data was collected in five separate questionnaire-based social surveys that were administered between 1996 and 2000. During the study, residents experiencedthe direct impact of two land-falling tropical cyclones. In addition to this, targeted andfocussed tropical cyclone awareness education was made increasingly available withinthe community. The social and demographic attributes that influence the individual'sperception of risk and contribute to our understanding of community vulnerability were examined and evaluated. Changes in the residents' attitudes, cyclone preparednessbehaviours and willingness to respond to cyclone warnings were monitored and measured. Analysis of early survey data indicated that community residents generally had some knowledge of cyclones but a limited understanding of cyclone processes and very little direct personal experience of the cyclone hazard. Individually and collectively, residents frequently demonstrated a biased perception of the risks associated with cyclones. The resident community was shown to be fragmented, with limited support being available to individual households. Initially, residents were found to be poorly prepared for cyclones and unlikely to respond to warnings appropriately. It appeared that, in the event of a land-falling tropical cyclone impacting the area, the community was highly vulnerable to unnecessary loss of property, livelihood and – in extreme circumstances – life. By 2000, Cairns community residents were somewhat better informed about cyclones and certainly more experienced. This paper provides some insight into how cyclone experience and education may synergisticly have contributed to a change in risk perceptions and a reduction in the vulnerability of Cairns residents to the tropical cyclone and storm surge hazards.  相似文献   
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