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31.
 This study presents a program for risk management in the contamination of groundwater resulting from leachate in landfills at Mar del Plata (Argentina). The program includes prediction, prevention, monitory observation and mitigation as actions that must be taken prior to, during, and after contamination occurs. This routine aids in the identification of weak points and failures of the program for those who are in charge of making decisions, and will allow better use of limited financial and technical resources based on planning, thus minimizing disconnected determinations. Results of the prediction stage were confirmed through monitoring. The presence of a plume of contamination more than 100 m from the landfill was shown, thus proving that implementation of a monitoring plan to follow the development of the contaminated plume must be implemented, particularly in populated areas which depend on residential wells for their water supply. Received: 8 May 2000 · Accepted: 14 August 2000  相似文献   
32.
The Soufriere volcano is a 1220 m high stratovolcano which occupies the northern part of the island of St. Vincent. It is one of the most active centres of volcanism in the Caribbean and has a record of activity dating back to the Pleistocene. Historic eruptions (since 1718) have caused over 1600 deaths and resulted in damage to property valued in excess of 4.8 million USD. In addition, current development plans for the area point towards increased risk of disastrous consequences from future activity at the volcano.All aspects of risk relevant to the volcano, are discussed, with particular emphasis on the manner in which these are perceived and on the question of acceptable risk. A method is presented for use in risk assessment of volcanic hazard and a number of risk zones are defined for the Soufriere volcano. Numerical estimates of the relative loss expected within each zone are obtained from a consideration of the value of property at risk, its vulnerability to the hazardous volcanic events and the expected spatial impact of volcanic events. Such estimates suggest that the northern-most third of the island is at least ten times more at risk than areas further south. The likelihood of death and destruction is extreme in such high risk areas, while the most feasible method of loss reduction is evacuation before an eruption occurs.Formerly at Department of Earth Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom.  相似文献   
33.
一种利用贝叶斯最小判别准则估计未来地震危险的新方法   总被引:2,自引:0,他引:2  
提出了一种基于最大似然和贝叶斯最小判别准则的新预测方法,它的长处在于对样本数无特殊要求,所以,对低地震活动地区,此模型也能得到与时间有关的稳定的未来强震危险估计。最后,以华北地区为例,说明了本方法的可行性。  相似文献   
34.
彭亮  汪海涛  王兆云 《内陆地震》2007,21(2):149-154
采用判别标志、对比判断方法,尤其是概率分析方法对喀腊塑克水库诱发地震进行了分析。概率分析方法是利用诱震水库和未发震水库的统计资料,考虑了库深、库容、构造应力环境、断层活动性及诱震区介质条件5个因素,再利用概率统计中的贝叶斯公式建立了预测水库能否诱震的概率模型,最终计算出结果。另外,从库区断层活动性及断裂所通过的位置、库水深度及岩石坚硬程度等方面,分析出可能产生诱发该水库地震的位置。结合工作中的体会,提出评价水库诱发地震的步骤和方法。最终分析结果表明,喀腊塑克水库诱发地震的可能性不大。  相似文献   
35.
Obesity is a serious public health problem in the United States. It is important to estimate obesity prevalence at the local level to target programmatic and policy interventions. It is challenging, however, to obtain local estimates of obesity prevalence because national health surveys such as the Centers for Disease Control and Prevention (CDC) Behavioral Risk Factor Surveillance System (BRFSS) are not designed to produce direct estimates at the local levels (e.g. census tracts) due to small population samples and the need to preserve individual confidentiality. In this study we address the problem of estimating local obesity prevalence rates by implementing a spatial microsimulation modeling technique to proportionally replicate the demographic characteristics of BRFSS respondents to census tract populations in metropolitan Detroit. Obesity prevalence rates are examined for high and low spatial clusters and studied in relation to the U.S. Department of Agriculture's (USDA) measures of low-income neighborhoods and local food deserts and CDC's measure of healthy and less healthy food environments currently used to target obesity reduction initiatives. This study found that obesity prevalence was largely clustered in the City of Detroit extending north into contiguous suburbs. The spatial patterns of highest obesity prevalence tracts were most similarly aligned with USDA-defined low-income tracts and CDC's less healthy food tracts. The locations of USDA's food desert tracts rarely overlapped with the highest obesity prevalence tracts. This study demonstrated a new methodology by which to assess local areas in need of future obesity interventions.  相似文献   
36.
The objective of the paper is to investigate the links between the patterns of incidents, the amount of hazardous materials locally present and capability of local emergency preparedness in rural local government councils. Four states Abia, Akwa Ibom, Bayelsa and Rivers State were used to examine the nature and pattern of oil-spill disasters in rural Nigeria. It is argued that oil-spill hazards are more than isolated engineering malfunctions. They can be alternatively understood as reflections of the social, economic and political contexts in which they occur. Discriminant analysis is used to examine the relationship between 71 country risk-related and preparedness variables and incident frequency. The findings illustrate the usefulness of contextual analysis in examining the restructuring of rural life and the capacity of fiscally and socially stressed rural communities to respond to environmental change.  相似文献   
37.
In this paper, the results of a survey conducted in the Cukurova region of Turkey are presented. The aim of this research is to identify groups of farmers who differ in their risk sources and risk management strategies. The respondents to the survey were divided into three risk attitude groups, risk averse, risk seeking and risk neutral. Factor analysis has been conducted on information obtained from 112 farmers in 2000. From the findings of the research, risk sources were labelled as environmental, price, catastrophe, input costs, production and technological, political, finance, personal, marketing, health and social security. The dimensions of risk strategies were named as diversification, off-farm income, marketing, planning, financing and security.  相似文献   
38.
矿山地质环境风险决策是一个涉及诸多利益群体的多目标决策问题。为了在矿山开发和关闭中有效地控制地质环境风险,我们提出了由风险在可接受水平内、风险控制工程效益达到最大和矿区规划科学合理3个目标组成的多目标决策问题,并采用层次分析法求解该决策问题。最后,将决策过程用于广西凤山城区内某废弃石灰岩矿山,综合设计单位、政府部门和当地群众的意见后,完成了矿山地质环境治理方案的决策。决策结果认为,采用P1(削坡、清理危岩、坡面锚固)、P2(截水+落石平台拦截+监测)、P3(坡面整形+岩壁雕刻+部分生态恢复)和P4(风险教育)的组合是最优治理方案。研究成果不仅有效地指导了该石灰岩矿山的地质环境治理工程,也对发展矿山关闭理论和风险管理具有重要作用。  相似文献   
39.
董鹏  蔡云  杨建华  李燕 《贵州地质》2021,38(4):437-442
岩溶塌陷是多因素相互影响,成因机制较为复杂的地质灾害类型,在空间上具有隐蔽性,时间上具有突发性的特征。为有效预测、评价岩溶塌陷危险性,本文采用GRA -FAHP,从岩溶条件、覆盖层条件、地下水条件、工程活动条件等因素出发,选取14个主要影响指标构建定性与定量相结合的岩溶塌陷危险性评价模型,以贵州省独山县交摆村岩溶塌陷区为例对模型进行验证。结果表明,该模型对岩溶塌陷危险性评价与实际情况相符。可为今后岩溶塌陷危险性的预测、评价提供一些借鉴。  相似文献   
40.
While ocean acidification (OA) poses a significant threat to ocean-related ecosystems and communities reliant on marine fisheries, aquaculture, and coral reef systems, limited public understanding and awareness can prevent coastal regions from being able to adequately assess the need for OA adaptation or mitigation. This study assessed public understanding of OA and how social and demographic factors influence the public’s concern for OA. The analysis was based on 311 questionnaires from full-time Alaska residents. The results showed that most Alaskans self-reported to have a basic awareness of OA, and subsequently were able to recognize that CO2 emissions related to human activity are the dominant driver of changing ocean conditions. However, there was a low recognition of how natural variability in the marine environment affects OA, and most respondents were not very confident in their understanding of OA-related science. Moreover, even though many communities in Alaska are reliant on commercial and subsistence fishing activities, the respondents had a low awareness of fisheries-related OA risk. Given the ongoing debate associated with climate change research, evaluating CO2 mitigation efforts through the perspective of OA could give individuals an unbiased way to assess the pros and cons of more intensive efforts to curb CO2 emissions. Furthermore, using OA communication to enhance the understanding of how natural variability influences OA around the state and the potential economic implications for Alaska fisheries would help residents and stakeholders make informed decisions when considering fisheries management plans, food security, and job diversity as OA intensifies. Solidifying the understanding that any reduction in pH and intensification of OA can have implications for marine species that are irreversible on human timescales will reinforce not only that OA is an immediate concern, but also the importance of taking action now.  相似文献   
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