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131.
Zhao L  Chen Z  Lee K 《Marine pollution bulletin》2008,56(11):1890-1897
Produced water discharge accounts for the greater portion of wastes arising from offshore oil and gas production operations. Development and expansion of Canada’s offshore oil and gas reserves has led to concerns over the potential long-term impacts of produced water discharges to the ocean. To examine this emerging environmental issue at a regional scale, an integrated risk assessment approach was developed in this study based on the princeton ocean model (POM), a random walk (RW) and Monte Carlo simulation. The use of water quality standards arrayed in a Monte Carlo design in the developed approach has served to reflect uncertainties and quantify environmental risks associated with produced water discharge. The model was validated against field data from a platform operating off Canada’s east coast, demonstrating its usefulness in supporting effective management of future produced water discharge.  相似文献   
132.
Using the actual damage data of the strong earthquakes in Taiwan, the effectiveness of the earthquake risk indices, namely, peak ground acceleration (PGA) and spectral intensity (SI), is verified. PGA and Housner's [Housner GW. Spectrum intensity of strong-motion earthquakes. In: Proceedings of symposium on earthquakes and blast effects on structures. EERI, UCLA; 1952] definition of SI are directly compared. A three-parameter spectral intensity system with spectral intensities SIa, SIv, and SId in the acceleration, velocity, and displacement regions, respectively, is discussed. Here, the effectiveness of SI, SIa, SIv, and SId has been compared by using the available earthquake-damage data in Taiwan. Three period ranges, namely, 0.1–0.6, 0.6–1.6, and 1.6–3.0 s were used for structures of 1–6 stories, 7–20 stories, and 21 and more stories, respectively. The results indicate that the three-parameter system is a good risk index of the damage potential of earthquakes.  相似文献   
133.
We present an Atlas of ShakeMaps and a catalog of human population exposures to moderate-to-strong ground shaking (EXPO-CAT) for recent historical earthquakes (1973–2007). The common purpose of the Atlas and exposure catalog is to calibrate earthquake loss models to be used in the US Geological Survey’s Prompt Assessment of Global Earthquakes for Response (PAGER). The full ShakeMap Atlas currently comprises over 5,600 earthquakes from January 1973 through December 2007, with almost 500 of these maps constrained—to varying degrees—by instrumental ground motions, macroseismic intensity data, community internet intensity observations, and published earthquake rupture models. The catalog of human exposures is derived using current PAGER methodologies. Exposure to discrete levels of shaking intensity is obtained by correlating Atlas ShakeMaps with a global population database. Combining this population exposure dataset with historical earthquake loss data, such as PAGER-CAT, provides a useful resource for calibrating loss methodologies against a systematically-derived set of ShakeMap hazard outputs. We illustrate two example uses for EXPO-CAT; (1) simple objective ranking of country vulnerability to earthquakes, and; (2) the influence of time-of-day on earthquake mortality. In general, we observe that countries in similar geographic regions with similar construction practices tend to cluster spatially in terms of relative vulnerability. We also find little quantitative evidence to suggest that time-of-day is a significant factor in earthquake mortality. Moreover, earthquake mortality appears to be more systematically linked to the population exposed to severe ground shaking (Modified Mercalli Intensity VIII+). Finally, equipped with the full Atlas of ShakeMaps, we merge each of these maps and find the maximum estimated peak ground acceleration at any grid point in the world for the past 35 years. We subsequently compare this “composite ShakeMap” with existing global hazard models, calculating the spatial area of the existing hazard maps exceeded by the combined ShakeMap ground motions. In general, these analyses suggest that existing global, and regional, hazard maps tend to overestimate hazard. Both the Atlas of ShakeMaps and EXPO-CAT have many potential uses for examining earthquake risk and epidemiology. All of the datasets discussed herein are available for download on the PAGER Web page (). T. I. Allen and M. G. Hearne—contracted through Synergetics Incorporated.  相似文献   
134.
北京市生产性服务业的增长及其空间结构   总被引:4,自引:1,他引:3  
基于北京1997年投入产出表、2002年投入产出表和第一次经济普查数据,采用投入产出模型、区位商等方法.分析北京市生产性服务业的增长结构变化、对地区经济的影响,以及典型生产性服务业行业的空间结构.研究表明.北京生产性服务业明显呈现出以金融、商务和信息服务业为主的格局;生产性服务业主要为第三产业服务;服务业对金融、商务、信息等生产性服务业的中间需求呈上升趋势;制造业对中间投入服务的消耗层次明显提高,产业结构不断优化升级;生产性服务业既有较强的经济推动能力,又对经济发展的需求较大;北京市生产性服务业的空间结构总体呈现圈层特征.  相似文献   
135.
产业集群是国内非常重要的经济现象, 但是如何辨识产业集群却一直困扰着学术界和政 府部门, 关键问题是产业集群缺乏统一的辨识标准。浙江省拥有数量众多的制造业产业集群, 而 且涉及的产业门类非常广泛, 是我国产业集群发展最为典型的省份之一。本文利用2001 年浙江 省基本单位普查数据, 同时选取浙江省各个邮区的四位数产业就业区位商≥3 以及该产业内的 企业数目≥100 家这两个标准, 进行产业集群的辨识, 共辨识了116 个典型产业集群。结果表明, 按照该辨识标准, 能够辨识出典型的制造业产业集群, 而且每个产业集群都具有明确的产业门类 及地理边界。文章最后部分归纳了浙江省典型制造业集群的空间分布以及规模结构等特征。  相似文献   
136.
The evaluation of potential rock slope problems using stereographic projection techniques known as kinematic analysis is one of the most important parts of a slope stability investigation to be carried out in jointed rock media. In conventional stereoprojection techniques for the assessment of possible rock slope failures, the peak orientations of joints together with the slope geometry and the friction angle of the weakness planes are used. Other possible joint orientations which may be encountered in the rock media are ignored, although they belong to the group of joint peak orientations. In this study, nearly vertical jointed andesites cropped out at the Altindag settlement region in Ankara were studied in order to evaluate the relevance of this ignored discontinuity orientation data on slope stability. As a result, probabilistic risk maps for planar, toppling and wedge failures were produced using the kinematic rules and digital elevation model of the study area. The comparison of the distribution of the actual failures in the area and the probabilistic risk maps prepared for the study area revealed that all of the identified failures are found to be located in the higher risk zones on the probabilistic risk maps.  相似文献   
137.
金江军  潘懋  徐岳仁 《内陆地震》2007,21(2):135-141
从危险性评价、易损性评价以及防灾减灾能力评价3个方面阐述了城市地震灾害风险评价内容.回顾了地震灾害风险评价研究进展,指出了现有评价方法的不足.提出了基于地震小区划的城市地震危险性评价方法、基于城市用地类型的城市地震易损性评价方法以及基于专家打分法的城市防震减灾能力评价方法.最后设计了城市地震灾害风险评价流程,并给出了城市地震灾害风险区划算法.  相似文献   
138.
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   
139.
国外灾害风险管理对我国城市洪水保险的启示   总被引:3,自引:0,他引:3  
全球变化和城市化的共同作用将导致城市洪涝灾害加剧,在这一新背景下,结合国外灾害风险管理的研究,对洪水保险进行了有益的探索,针对以前我国洪水保险试点在农村地区失败的原因,提议我国应该从城市开始实施洪水保险计划,认为实施城市洪水保险有必要性和可行性,可以进一步拓展城市洪涝灾害风险管理的渠道。  相似文献   
140.
煤矿塌陷是煤矿地质灾害危险性评估的核心内容。本文以孙村煤矿为例,进行了采空塌陷的危险性预测,并提出了防治措施。  相似文献   
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