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71.
研究目的:通过编制盐都区工业用地绩效编码,分析绩效编码的含义对工业用地集约利用现状的解释能力,验证责任定位法是一个科学实用的绩效评价方法。研究方法:归纳分析法和实证检验法。研究结果:(1)责任定位法中每个指标代码能够真实反应相应评价指标的绩效等级,不涉及权重和综合得分问题,克服了综合评分法评价结果可比性低的特点。(2)绩效编码能够客观直观地衡量工业用地的集约利用效果,其含义与原始数据所反映的用地绩效情况相符。研究结论:(1)责任定位法具有科学性,绩效编码没有歪曲、偏离宗地绩效的实际情况。(2)责任定位法给出的宗地绩效信息具有实际使用价值,可以反应宗地绩效高低的直接原因,指导企业和管理部门采取相应措施提升用地绩效或清退低效用地。  相似文献   
72.
This paper integrates two key approaches to the representation of incomplete preferences over lotteries. The main result strengthens the conclusion of the expected multi-utility theorem in Dubra, Maccheroni, and Ok (2004) by ensuring that all utility indices involved are Aumann utilities (i.e., yield a strictly increasing expectation). The advantages of the method are demonstrated by parametrizing maximal elements and by providing a novel characterization of Aumann utilities.  相似文献   
73.
为解决乡村土地旅游化流转风险评价问题,构建了包含粮食安全受威胁程度、收益分配不公平程度、土地利用结构失衡程度、乡村生态破坏程度以及乡村特色消失程度的乡村土地旅游化流转风险评价指标体系,提出乡村土地旅游化流转风险评价的集对分析—可变模糊模型与方法。首先,基于集对模糊联系度构造可变模糊集理论的相对差异度,进而建立集对分析—可变模糊综合评价模型;然后,结合风险分级特征值运用二元语义方法确定乡村土地旅游化流转风险级别;最后,以泉州市乡村旅游目的地为例进行了实例计算。研究结果表明,所建立的集对分析—可变模糊评价模型与方法不但能够定量辨别乡村旅游地土地旅游化流转的风险等级,而且能够区分同一风险等级下的不同风险大小。  相似文献   
74.
Landscape is defined by the European Landscape Convention as “an area perceived by people, whose character is the result of the action and interaction of natural and/or human factors”. Many efforts have been devoted in addressing the core concepts on which this definition roots: perception and interaction of men and nature, but when coming to large (continental) scale assessments, the latter prevail on the former.This paper aims at presenting a framework for a measurable landscape awareness indicator as a key link to the public demand for a specific type of landscape: the agricultural landscape. This is a necessary effort to complement more physically based assessments, which include as well the impact of human activities on landscapes.The analysis is carried out at different levels of governance: EU and regional, using an example from the Alentejo region in Portugal and EU wide databases, and addresses conceptual and practical questions: what type of societal landscape awareness can be monitored and by whom (e.g., individuals, specific social groups, society as a whole); what are the landscape dimensions that should be assessed; what are the limitations imposed by data-related constraints. By applying the methodology to build composite indicators to map landscape societal awareness, the paper shows the regional and local meaning of indicator approaches developed at European level, presents developments for downscaling to regional level, while introducing the social component to support sound policy development for European rural landscapes.  相似文献   
75.
Though most landscape ecologists have integrated scaling issues in their works, these issues are often disregarded in landscape perception and preference studies. Researchers base their studies on a predefined single scale to assess the landscape, and they pay little attention to the scale specificity of their analysis and recommendations. We reconsidered three landscape assessment studies from our research unit in light of scaling issues. In addition to the scale of the assessed landscape, researchers should address the scale of the landscape surrogate that is submitted for assessment, including the spatial references of the people surveyed and the target level of application of the results. Indeed, many of the landscape assessment methods mix different landscape notions and scales. Therefore, we recommend the cautious use of these assessments, the integration of qualitative insights in addition tithe scoring and paying attention to the perception scale, as defined by Fairclough (2006).  相似文献   
76.
In this study, ten bioenergy crop rotations (corn, corn-stover, sorghum, soybean, corn-soybean, corn-soybean-canola, corn-stover-soybean, miscanthus, switchgrass, and sorghum-soybean) were selected based on local stakeholder (economically motivated) and regulator (environmentally motivated) preferences. These crops were implemented on diverse landscapes (agricultural, marginal, and agricultural plus marginal lands) one at time for 17 years using a SWAT model of the Saginaw River Watershed in Michigan. The bioenergy crops were evaluated based on 100 percent, 50 percent, and zero percent weight assigned to both stakeholders’ and regulators’ preferences using analytic hierarchy process (AHP), an optimization and decision-making technique that aims to satisfy multiple conflicting objectives. The corn-soybean-canola rotation was selected in all landscapes based on economic benefits (stakeholders’ preferences). Meanwhile, perennial grasses (miscanthus and switchgrass) were selected based on environmental benefits (regulators’ preferences), because they maintain permanent cover, require fewer inputs than traditional row crops, and are less management intensive. When implementing bioenergy crops on marginal lands, pollution generation greatly increased at the field level, indicating that these lands are likely not viable for bioenergy crop production to meet potential future renewable energy demand.  相似文献   
77.
The purpose of this study was to develop a systematic process that other educational institutions and programs could follow to establish a consistent and accurate evaluation method for a capstone course. Hospitality industry professionals and hospitality management faculty were interviewed through focus-group discussions, and a post-focus-group survey was conducted to determine a weighted percentage for each of the nine determined content domains. A test blueprint for a hospitality management capstone course was developed to measure programmatic student learning outcomes based on the weighted domains determined through this study. The results provide a usable instrument for hospitality and tourism management programs to enhance their current assessment methodology.  相似文献   
78.
While a careful and accurate debt sustainability assessment (DSA) is crucial for an efficient macroeconomic management, the most widely used framework introduced by the International Monetary Fund (IMF) suffers from several drawbacks that render its results overoptimistic and misleading. In this article, we correct the methodology by demonstrating how policy makers can develop country-specific “intermediate” forecasts of the determinants of debt dynamics, in addition to coherent “optimistic” and “pessimistic” scenarios. Our application to the case of Egypt illustrates that the debt-to-GDP ratio could increase to more than 100 percent by 2015, in contrast with the 61 percent projected by the IMF in 2010.  相似文献   
79.
In this paper, we consider the optimal proportional reinsurance strategy in a risk model with two dependent classes of insurance business, where the two claim number processes are correlated through a common shock component. Under the criterion of maximizing the expected exponential utility with the variance premium principle, we adopt a nonstandard approach to examining the existence and uniqueness of the optimal reinsurance strategy. Using the technique of stochastic control theory, closed-form expressions for the optimal strategy and the value function are derived for the compound Poisson risk model as well as for the Brownian motion risk model. From the numerical examples, we see that the optimal results for the compound Poisson risk model are very different from those for the diffusion model. The former depends not only on the safety loading, time, and the interest rate, but also on the claim size distributions and the claim number processes, while the latter depends only on the safety loading, time, and the interest rate.  相似文献   
80.
Birdstrikes are a major hazard to aviation; costing millions of pounds a year in damage and delays, as well as occasional hull losses and loss of life. The numbers and species of birds on and around airfields therefore need to be managed. To aid this process, airport staff often use risk assessments to identify which bird species cause the greatest risk and use the outcome to target their bird control effort. To this end, a number of national and international regulators, airports and other organisations recommend, or use, a derivation of a risk assessment process first published in 2006. This was developed using the UK Civil Aviation Authority's birdstrike database, employing data collected between 1976 and 1996. The risk assessment process relies on using the proportion of reported strikes that cause damage to the aircraft as a proxy for the likely severity of the outcome of strike incidents, so any change in the relative level of reporting of damaging and non-damaging strikes may significantly bias the results. The implementation of mandatory birdstrike reporting by the UK CAA in 2004 led to a significant increase in the number of strikes reported. If this involved a disproportionate increase in the number of non-damaging compared to damaging incidents reported, it may have impacted on the accuracy of the risk assessment process. This paper examines how differential reporting of damaging and non-damaging strikes can impact on the risk assessment process. It shows that changes in reporting practices since the original risk assessment was developed have impacted on the apparent birdstrike risk at UK airports, giving a false impression of increasing risk over the period. It makes recommendations for how the process can be better adapted to cope with such changes in the future, and how it should be modified for use in countries with different reporting regimes to that in the UK.  相似文献   
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