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1.
西南矿区山体崩塌成因机制分析及防治对策   总被引:1,自引:0,他引:1  
西南地区的矿区具有相似的地理、地质环境,通过四川芙蓉煤矿白岩崩塌的典型实例,对西南矿区山体崩塌的成灾环境进行调查研究,揭示了西南矿区山体崩塌的成因机制,并简要提出了对该煤矿开发与综合治理建议,指出了加强防治工作的紧迫性,强调开展系统工程防灾的重要性,并为该煤矿解决正常采掘接替及工作面的布置问题作出了科学的指导.  相似文献   
2.
Sdsealbedoisdefinedasaratioofreflectivesolarradiationtototalacradiation,whichcanindicatetheaborptionandreflectivecapabilityofthe~hforsolarradiation.Itisan~tfactortoinfluencethes~radiationbalance,espeiallyfortheformationandvariationoflocalndcroclirnate.Generally,theactualdatafromo~tionalstationSforrebationareedintheanalysisofsolacealal.HOwever,therepresentativenessOfthedateisIratedduetothescarcityofobservationalstationandunevendistributionofs~condition.Afterthe1960s,theanalysisfors~ealbedoise…  相似文献   
3.
概略地叙述了西宁地区的泥石流形成条件和形成机理,并将西宁地区泥石流划分为稀性泥石流类及泥石质泥石流种类。在此基础上提出防治泥石流灾害的意见。  相似文献   
4.
In recent years, many coal-producing countries have paid great attention to the land subsidence causedby coal cutting. In China, because of the dense population in coalfield areas, the land subsidence hazard is more seri-ous. After a brief analysis on the mechanism of land subsidence, this paper gives a comprehensive and systematical ac-count on all kinds of hazards caused by the land subsidence in China. The study shows that land subsidence has endan-gered land, buildings, traffic and communication lines, dykes and dams. It also causes damage to ecological and socialenvironment. In order to lessen the hazard of land subsidence, preventive measures should be taken to reduce the col-lapse amount, such as extraction with stowing, banded mining system, succession and coordination mining system, orhigh-pressure mudflow between rock strata. Measures of reinforcing or moving certain buildings should also be taken toreduce the destructive degree. In order to harness the subsidence land and bring them under control for fanning, mea-sures should be taken such as filling with spoil or fine breeze, excavating the deeper and covering the shallower land.  相似文献   
5.
In recent years,scholars at home and abroad have method,and that vanous disasters would be analyzed assynthetically studied natural dlsaste‘theoretically and an Integral.SHI Peilun(1991)putforwad a scientificmethodologlcally,as well as its cases analys。s(CND,term—regional disaster system,which Indicates that1987; MA et al,1990; MARBLE,1990; NE et al,the situation of a disaster(calamity loss)results from1999; PATAK et al,1982; SHI,1991;VAN et al,h…  相似文献   
6.
In 1903 the Swiss Federal Research Institute WSL started its first forest hydrology measurements with the aim to deliver a sound scientific basis for the implementation of new forest legislation introduced in Switzerland in 1876. This legislation was triggered by several large floods that occurred in Switzerland, for which a major cause was widely seen as the poor condition of forests at that time. Consequently, hydrologic research at WSL first focused on the influence of forests on floods. In the second half of the 20th century, other hydrological issues such as water quality, snow hydrology and sediment transport complemented the hydrologic research at WSL. Some recent results of this work are presented in three papers joining this introductory paper to mark the 100th anniversary of hydrologic research at WSL. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
7.
David King 《Natural Hazards》2008,47(3):497-508
The concept of a natural hazard is a human construct. It is the interaction with human communities and settlements that defines a natural phenomenon as a natural hazard. Thus the end point of hazard mitigation and hazard vulnerability assessment must involve an attempt to reduce, or mitigate, the impact of the natural hazard on human communities. The responsibility to mitigate hazard impact falls primarily upon governments and closely connected non-government and private institutional agencies. In particular, it is most often local government that takes the responsibility for safeguarding its own communities, infrastructure and people. Hazard vulnerability of specific local communities is best assessed by the local government or council, which then faces the responsibility to translate that assessment into community education and infrastructural safeguards for hazard mitigation. This paper illustrates the process of local government engagement in hazard mitigation in Australia, through the Natural Disaster Risk Management Studies, as a first step towards natural disaster reduction.  相似文献   
8.
浙江省小流域山洪灾害临界雨量确定方法分析   总被引:12,自引:2,他引:10  
叶勇  王振宇  范波芹 《水文》2008,28(1):56-58
小流域山洪灾害具有突发性,预测预警难度较大.本文结合浙江省小流域山洪灾害防御的实践经验,研究提出了以水位反推法计算临界雨量,简单实用,具有较好的实践价值和推广意义.  相似文献   
9.
Low-frequency damping of a moored semisubmersible drilling platform was obtained from numerical extinction tests simulated in still water and in regular waves and from mean wave drift forces calculated at zero forward speed. The influence of drag forces was represented by the modified Morison equation. The platform as used for the 18th ITTC Comparative Mooring Study was analyzed in irregular beam waves. The computed time series of sway as well as the corresponding sway response spectrum compared favourably with model test measurements, demonstrating that this procedure to determine low-frequency damping can be effective.  相似文献   
10.
Using the National Center for Enviromental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis data and NOAA satellite-obser ved outgoing long-wave radiation (OLR) data, the development of the South China Sea (SCS) summer monsoon and intraseasonal (30-60 d) oscillation (ISO) have been examined. The results show that there exists obvious interannual variability of intraseasonal oscillaiton. Using the 16 a time series of filtered OLR averaged over the SCS, an index is defined to define ““onset events““ over the SCS on the ISO time scales. Of the 16 a examined here, 10 shows a strong ISO signal in the onset of monsoon convection over the SCS. In these cases, the ISO initially suppresses the seasonal development of southwesterly and cyclonic circulation over the SCS before the ISO onset. As the ISO propagates northeastward, the low frequency cyclonic circulation anomaly occurs in the SCS and the low frequency southwesterly wind and convection over here dramatically intensify. The northeast progression of the ISO anomaleis plays a role in the initial suppression and then acceleration of the seasonal cycle of the SCS summer monsoon.  相似文献   
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