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91.
ABSTRACT: During August and September 1973, the Indus River Valley of Pakistan experienced one of the largest floods on record, resulting in damages to homes, businesses, public works, and crops amounting to millions of rupees. Tremendous areas of lowlands were inundated along the Indus River and major tributaries. Landsat data made it possible to easily measure the extent of flooding, totaling about 20,000 km2 within an area of about 400,000 km2 south from the Punjab to the Arabian Sea. The Indus River data were used to continue experimentation in the development of rapid, accurate, and inexpensive optical techniques of flood mapping by satellite begun in 1973 for the Mississipi River floods. The research work on the Indus River not resulted in the development of more effective procedures for optical processing of flood data and synoptically depicting flooding, but also provided potentially valuable ancillary information concerning the hydrology of much of the Indus River Basin.  相似文献   
92.
ABSTRACT: Runoff Routing model (RORB) is a general model applicable to both rural and urban catchments. The performance of the model is illustrated through its simulation of flood runoff hydrographs in an urban catchment in Singapore. The essential feature of the model is the routing of rainfall excesses on subareas through some arrangement of concentrated storage elements, which represent the distribution of temporary storage of flood runoff on the watershed. This nonlinear routing procedure of the storage elements has two common parameters, kc and m. With the limited data available, these two parameter values were determined through calibration runs. The same set of values of kc and m were then used in the model to determine the runoff hydrographs of five other storms selected from the rainfall events between 1979 and 1981. It was found that the simulated runoff hydrographs matched reasonably well with the recorded hydrographs.  相似文献   
93.
ABSTRACT: A regression analysis using a generalized least squares approach on flow data from the driftless area of Wisconsin indicates that the ratio of drainage area to time-to-peak is a good predictor of flood quantiles. The estimation of time-to-peak (or some other measure of basin response time) requires direct measurement of river stage and possibly rainfall at the site of which the quantiles are to be estimated. The cost-effectiveness of such an approach must yet be determined.  相似文献   
94.
通过对南方某省1988~1992年工伤发生情况的调查,五年间工伤事故数、工伤死亡率及重伤率有逐年增加的趋势,煤炭、交通、建筑三个行业的工伤死亡人数约占工伤死亡总数的50%;县以下乡镇企业中的工伤事故数、死亡率及重伤率均居首位。工伤事故中造成死亡的原因主要集中在物体打击、触电、高空坠落;引起重伤的原因集中在机械伤害、物体打击、车辆伤害和高空坠落。因此在劳动安全卫生管理工作上,要采取一些强有力的干预措施,特别要加强对乡镇工业企业及那些易发生工伤事故企业的管理。  相似文献   
95.
ABSTRACT: Evaluation criteria for reservoir and stream resources were developed to provide decision makers with feedback on environmental consequences of water allocation decisions under conditions of severe sustained drought within the Colorado River Basin by using the AZCOL gaming simulation model. Seven categories of flow dependent resources were identified which highlight resource states associated with reservoirs or river reaches within the AZCOL model. AZCOL directly simulates impact of water management decisions on five resource categories: threatened, endangered or sensitive fish; native nonlisted fish; wetland and riparian elements; national or state wildlife refuges; and hatcheries or other flow dependent facilities. Two additional categories - cold and warm water sport fish - are not modeled explicitly but are incorporated in the evaluation of monetary benefits from recreation on Colorado River waters. Each resource category was characterized at each time step in the simulation according to one of four environmental states: stable, threatened, endangered, or extirpated. Changes in resource states were modeled by time and flow-dependent decision criteria tied to either reservoir level or stream flows within the AZCOL model structure. Gaming results using the AZCOL model indicate environmental impacts would be substantial and that water allocation decisions directly impacted environmental resource states.  相似文献   
96.
本文概述了1994年华南洪灾的情况,指出水灾反映出城市防洪中存在的有关问题,并总结了防洪成功的经验,作为今后的借鉴。  相似文献   
97.
水灾害治理对种植业生产的影响   总被引:1,自引:0,他引:1  
为了应对水灾对我国种植业生产的破坏,国家每年要投入大量资金用于防灾减灾工作,在对1980年以来我国种植业生产、自然灾害和水利建设的统计数据进行描述性分析的基础上,通过建立模型,定量分析了26年来我国救灾工作和各种防灾水利建设对种植业增长所起的作用,为我国进一步制定科学有效的国家防灾减灾政策提供参考。  相似文献   
98.
The river Paz is a transboundary river that flows through Guatemala and El Salvador. Its frequent floods endanger the lives and livelihoods of downstream communities. Attempts have previously been made to develop flood management programmes for this watershed. However, these approaches were generally made by high-level governmental institutions with few if any contributions from floodplain communities and other stakeholders. Recognising that public consultation is a key aspect in flood management programmes, we intend in this work to extract different stakeholders' views regarding current and future flooding and flood management programmes in the Paz River basin. This is achieved using Future Scenarios Workshops with a projected time horizon of 30 years. The exercise was expected to identify consensual short- and medium–long-term flood management strategies for the Paz River basin that draws on input from inhabitants of flood-prone areas and other stakeholders.  相似文献   
99.
陕西省大旱年发生概率及可能发生的年份预测   总被引:4,自引:4,他引:4  
邢东兴  孙虎  延军平 《灾害学》2004,19(1):69-72
应用数理统计方法及三元、四元、五元可公度法分别推算了21世纪陕西省大旱年发生的概率和预测了该省未来30多年间可能发生大旱灾的年份.运算结果显示:陕西省在21世纪的100年中,大旱年发生次数至少为一次、两次、三次、四次、五次的概率分别为94.52%、86.65%、72.91%、54.78%、35.57%;在未来30多年间陕西省有可能在2006年、2008年、2024年、2031年发生重大旱灾.  相似文献   
100.
利用常规气象观测资料、NCEP再分析资料对2016年8月21日傍晚到夜间贺兰山沿山特大致洪极值暴雨展开研究,分析了异常大气环流形势及其影响,并利用天气研究和预报模式WRF(Weather Research and Forecasting model)进行数值模拟和地形敏感性试验,研究了贺兰山地形对暴雨过程的影响。结果表明:超强厄尔尼诺结束后的盛夏,大气环流形势发展异常,8月南亚高压和副热带高压异常偏强,西北地区东部处于高温、高湿、高能控制,副高的快速进退和冷平流的入侵,触发暖湿不稳定能量强烈聚集与快速释放,导致特大暴雨的爆发。其发生在200hPa高空急流分流区即强辐散区、中空西南气流的高温高湿区、低空偏南急流轴左侧流场最大弯曲处的强暖平流区、850hPa偏东大风速轴南侧的风速辐合区,天气尺度强迫作用相对较弱的环境中,500hPa短波槽与700hPa、850hPa低涡切变线和偏南偏东急流以及地面气旋式切变辐合线共同作用是其发生的主要影响系统。贺兰山地形对特大暴雨的发生有明显的增幅效应,主要是贺兰山地形阻挡与强迫抬升作用,促使低涡切变强烈发展从而影响了降水范围、强降水落区及其中心位置等。  相似文献   
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