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31.
湿地价值评估尺度转换方法——Meta分析研究概述   总被引:3,自引:0,他引:3  
湿地价值评估中的尺度转换是通过一个已经有的、与被估算生态系统相似的另一生态系统的价值来估算该湿地生态系统的价值量的过程。Meta分析(Meta-Analysis)是一种定量其他评价效应的大小,并进行综合分析评价的方法,是分析的分析,综合的综合,具有较高的统计效率及验证其他假设的功能,是一种较为精确的价值转移方法。阐述了Meta分析的定义,介绍了Meta分析的步骤及函数表达式,陈述了国内外学者对Meta分析的应用及研究进展,并对其未来的应用前景进行了展望。  相似文献   
32.
This paper presents a new approach for offshore risk analysis that is capable of dealing with linguistic probabilities in Bayesian networks(BNs).In this paper,linguistic probabilities are used to describe occurrence likelihood of hazardous events that may cause possible accidents in offshore operations.In order to use fuzzy information,an f-weighted valuation function is proposed to transform linguistic judgements into crisp probability distributions which can be easily put into a BN to model causal relationships among risk factors.The use of linguistic variables makes it easier for human experts to express their knowledge,and the transformation of linguistic judgements into crisp probabilities can significantly save the cost of computation,modifying and maintaining a BN model.The flexibility of the method allows for multiple forms of information to be used to quantify model relationships,including formally assessed expert opinion when quantitative data are lacking,or when only qualitative or vague statements can be made.The model is a modular representation of uncertain knowledge caused due to randomness,vagueness and ignorance.This makes the risk analysis of offshore engineering systems more functional and easier in many assessment contexts.Specifically,the proposed f-weighted valuation function takes into account not only the dominating values,but also the α-level values that are ignored by conventional valuation methods.A case study of the collision risk between a Floating Production,Storage and Off-loading(FPSO) unit and the authorised vessels due to human elements during operation is used to illustrate the application of the proposed model.  相似文献   
33.
Conjoint analysis is a useful technique to assist recreational managers formulate policy, and develop strategies to efficiently and effectively distribute resources. Accurate estimates of the value of natural resources remain challenging, despite the development of a number of decision analysis techniques. This recreation geography study uses conjoint analysis to examine the relative importance of attributes associated with small‐boat recreational fishing experiences and demonstrates the value of conjoint analysis as a non‐market valuation tool. We found that the choices associated with companionship are the most important factors of recreational fishing and more tangible attributes such as the quality of launch facilities and catch probability are the least important factors.  相似文献   
34.
Abstract

Abstract The identification of flood seasonality is a procedure with many practical applications in hydrology and water resources management. Several statistical methods for capturing flood seasonality have emerged during the last decade. So far, however, little attention has been paid to the uncertainty involved in the use of these methods, as well as to the reliability of their estimates. This paper compares the performance of annual maximum (AM) and peaks-over-threshold (POT) sampling models in flood seasonality estimation. Flood seasonality is determined by two most frequently used methods, one based on directional statistics (DS) and the other on the distribution of monthly relative frequencies of flood occurrence (RF). The performance is evaluated for the AM and three common POT sampling models depending on the estimation method, flood seasonality type and sample record length. The results demonstrate that the POT models outperform the AM model in most analysed scenarios. The POT sampling provides significantly more information on flood seasonality than the AM sampling. For certain flood seasonality types, POT samples can lead to estimation uncertainty that is found in up to ten-times longer AM samples. The performance of the RF method does not depend on the flood seasonality type as much as that of the DS method, which performs poorly on samples generated from complex seasonality distributions.  相似文献   
35.
Coastal habitats provide a variety of benefits for citizens living in littoral countries. The economic value of changes in coastal habitats in the context of the implementation of the Baltic Sea Action Plan, targeting good ecological status by 2021, in two coastal sites was estimated using the choice experiment method. The selected aspects of marine ecosystem were described in conjunction with ecological changes modeled within the Finnish–Swedish archipelago and the Lithuanian coast. The benefits for Finns, Swedes, and Lithuanians for changes in the adjacent coastal site were estimated with the conditional logit and random parameters logit models accounting for preference heterogeneity. The willingness to pay estimates for healthy perennial vegetation, protection of currently pristine areas, and size of fish stocks differed significantly between populations. The transfer errors ranging from 40%, when transferring the estimates for the same coastal site between populations, to 400%, when transferring between both sites and populations, underline careful consideration in value transfers.  相似文献   
36.
基于条件价值法评估罗源湾海洋生物多样性维持服务价值   总被引:4,自引:0,他引:4  
海洋生物多样性维持服务指海洋中不仅生活着丰富的生物种群,还为其提供了重要的产卵场、越冬场、索饵场、避难所、栖息地等场所.基于条件价值法,于2009年8月对福建罗源湾周边城镇居民进行问卷调查,掌握当地居民对保护罗源湾生物多样性的支付意愿,进而评估罗源湾生物多样性维持服务价值.结果显示,2009年罗源湾4种珍稀生物的支付意愿为618.8元/户.2004-2008年罗源湾生物多样性维持服务价值分别为747.17万元、1 912.52万元、2 565.08万元、3 821.92万元、5 272.00万元.分析表明:家庭年收入、对保护生物的了解程度和环保意识是影响生物多样性维持服务价值的主要因素.对于保护海洋生物多样性来说,经济发展政策和环保政策都是必要的,如何做好这2个政策的平衡是政府应该关注的.  相似文献   
37.
Assessments of climate change face the task of making information about uncertainty accessible and useful to decision-makers. The literature in behavior economics provides many examples of how people make decisions under conditions of uncertainty relying on inappropriate heuristics, leading to inconsistent and counterproductive choices. Modern risk communication practices recommend a number of methods to overcome these hurdles, which have been recommended for the Intergovernmental Panel on Climate Change (IPCC) assessment reports. This paper evaluates the success of the most recent IPCC approach to uncertainty communication, based on a controlled survey of climate change experts. Evaluating the results from the survey, and from a similar survey recently conducted among university students, the paper suggests that the most recent IPCC approach leaves open the possibility for biased and inconsistent responses to the information. The paper concludes by suggesting ways to improve the approach for future IPCC assessment reports. To cite this article: A. Patt, S. Dessai, C. R. Geoscience 337 (2005).  相似文献   
38.
单边界和双边界是二分式条件价值法(CVM)的2种主要问题格式。针对澳门固体废弃物管理存在的问题,应用单边界和双边界二分式条件价值法,比较研究了澳门固体废弃物管理方案改善的支付意愿及其总经济价值;结果表明,80.56%的居民对新的固体废弃物管理方案存在支付意愿。单边界二分式CVM的分析结果表明澳门居民的平均支付意愿为每人每月14.87~24.12澳门元。双边界二分式CVM的结果表明澳门居民的平均支付意愿为每人每月14.43~17.94澳门元。单边界和双边界二分式CVM的评估结果相差不大,双边界二分式CVM的评估结果较为精确。按2003年澳门总人口44.85万计算,新的固体废弃物管理方案的年总经济价值约为7.02×107澳门元。   相似文献   
39.
Green Valley, Arizona is a retirement community located near major open-pit copper mines. Mining and milling activities create dust, which degrades air quality, and mine dumps and tailings banks, which degrade the viewscape. Although the tailings banks are highly visible, this study found that consumer surplus lost from dust-polluted air is more than twice that from degradation of viewscape. Consumer surplus lost from both air quality and viewscape degradation is estimated to be between $116,000,000 and $169,000,000. These preliminary estimates are based upon two studies: hedonic property values, and a contingent valuation survey of willingness to pay.  相似文献   
40.
条件估值方法是当前国际上流行的衡量环境物品非利用经济价值的方法, 通过调查居民针对不同环境状况变化的支付意愿,从而定量确定环境状况变化带来的经济效益和损失. 针对黑河流域额济纳旗生态系统恶化的现状,以投标支付卡的方法设计了700份调查问卷,调查了黑河流域居民恢复额济纳旗生态系统的支付意愿,并采用非参数分析方法对结果进行分析. 结果表明,用20 a的时间将额济纳旗的生态系统恢复到20世纪80年代初的水平,黑河流域总共有92.3%的居民家庭存在支付意愿,有支付意愿家庭的平均支付意愿为每年每户43.39元,同时采用列联表检验的方法辨明了被调查者的年龄、学历、收入、户籍和居住的地理区域等因素对支付意愿的影响. 最后在综合不同区域居民支付意愿差异的基础上,采用当前的市场利率将计算结果在时空尺度上加总,得到恢复黑河下游额济纳生态系统的总经济价值的现值为2.94×10+8元.  相似文献   
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