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61.
To avoid both over-design and under-sizing of airport passenger terminal facilities such as security checkpoints, the infrastructure is designed for a specifically determined design load. As such, the design load is considered for a short period of time, usually an hour of operation, during which peak, though not necessarily maximum, demand occurs. For strategic planning applications, future design loads can be determined by either fictitious flight schedules or ratio-based models which forecast the relationship between design load and annual demand. This study presents two ratio-based methods which allow the direct determination of design hour loads (DHL) for passenger terminal facilities. The unsaturated DHL model considers the relationship between observed passenger flows in the terminal and aggregated annual demand data. The saturated DHL model includes several operational constraints which limit the actual DHL, such as limitations in the runway system or the fleet mix operating at an airport. Both models are applied to two real-world airports, for which the DHL of the security checkpoint facilities is estimated from large datasets covering multiple years. Results are significant at the 5 % level and suggest that the proposed ratio-based methods are appropriate for airport strategic planning applications.  相似文献   
62.
在行为经济学相关理论的基础上,基于福建山区221个农户的调研数据,运用有序Probit模型探究影响农户参与森林旅游业意愿的主要因素。研究结果表明:山区农户对森林旅游业的参与意愿不高;性别、健康状况、家庭成员是否为党员或干部、屋前是否通公路、家庭成员累计出外打工时间、对森林旅游政策了解程度、政府扶持力度及未来收益预期等因素是影响农户对森林旅游业参与意愿的主要因素。基于此,建议提高农村妇女参与森林旅游业的综合能力、加强政策的支持与引导及推进森林旅游业产业链延伸等。  相似文献   
63.
[目的]客观揭示农村贫困化地域分异机制,为科学推进川西北高原藏区精准扶贫创新途径、综合战略和认真贯彻落实中央治藏方略提供参考依据。[方法]应用地理探测器模型、GIS空间分析与地统计方法等方法,探测川西北高原藏区贫困村单位面积GDP分异的主导因素,揭示农村贫困化分异机制,提出不同贫困化地域类型的扶贫政策措施。[结果]影响川西北高原藏区农村贫困化分异的主导因素包括到主要交通道路距离、归一化植被指数(NDVI)、土地利用、年均温度和海拔高程等,各因素对贫困村经济发展分异的解释力分别为80. 76%、12. 82%、8. 82%、5. 45%和3. 96%;贫困村经济发展贫困化的分异机制存在明显差异,可归纳为交通区位约束型、自然环境约束型和经济区位约束型等三大类型;农村贫困化驱动机制下的贫困村精准扶贫政策措施亟需因地制宜、科学推进、讲求实效,有序推进精准扶贫战略。[结论]精准扶贫应分类指导、重点突破,尤其加强贫困村交通、水利、公共基础设施建设和特色农牧业产业培植,注重多种扶贫模式的综合集成。  相似文献   
64.
从1985-2018年海南城乡居民收入、消费数据出发,分别建立消费关于收入、消费差距关于收入差距的自回归模型,结果表明农村居民当期消费更易受近期收入和消费水平的影响,具有不稳定性。再利用GM(1,1)模型预测城乡居民收入差距,结合自回归模型,完成未来10年海南城乡消费差距的预测:收入差距和消费差距将呈直线递增趋势,收入差距的增幅高于消费差距增幅。缩小海南城乡居民消费差距的根本途径在于缩小收入差距,应因地制宜,切实提高农民收入水平。  相似文献   
65.
The reproducibility crisis, that is, the fact that many scientific results are difficult to replicate, pointing to their unreliability or falsehood, is a hot topic in the recent scientific literature, and statistical methodologies, testing procedures and p‐values, in particular, are at the centre of the debate. Assessment of the extent of the problem–the reproducibility rate or the false discovery rate–and the role of contributing factors are still an open problem. Replication experiments, that is, systematic replications of existing results, may offer relevant information on these issues. We propose a statistical model to deal with such information, in particular to estimate the reproducibility rate and the effect of some study characteristics on its reliability. We analyse data from a recent replication experiment in psychology finding a reproducibility rate broadly coherent with other assessments from the same experiment. Our results also confirm the expected role of some contributing factor (unexpectedness of the result and room for bias) while they suggest that the similarity between original study and the replica is not so relevant, thus mitigating some criticism directed to replication experiments.  相似文献   
66.
ABSTRACT

This article identifies the breakdowns in the covariance of three benchmark crude oil futures markets (WTI, Brent and Dubai) and investigates the changes of market connectedness across the breakdown periods. As the crude oil futures are traded in different regions, this article eliminates the non-synchronous trading data by employing the Vector Moving Average structure and the Bayesian data augmentation approach, which keeps the integrity of original data without changing its properties. The results show that there are significant breaks in the covariance structure of crude oil futures markets. The breakdown periods are consistent with the periods when the market volatilities are at high level and the returns are volatile. The changes of market connectedness are independent of the covariance states, which supports the globalization hypothesis for the crude oil market. The results also suggest that there is more information flow out of the WTI than to the WTI during the sample period, particularly during the breakdown periods in 2008–2009.  相似文献   
67.
Abstract

This study investigates whether work opportunities have an impact on stress and the related turnover intentions of employees working in intergovernmental international organizations (IOs). It contextualizes the job resources and demands model within IOs’ specific work conditions. The empirical test is based on original data from a survey administered in four major organizations of the United Nations system. Results demonstrate that social work opportunities and work–life balance are organizational levers reducing stress and willingness to quit for employees who are facing red tape or the stresses of being an expatriate. In this context, the relationships between these work opportunities and turnover intention are partially mediated by stress. Contextualized HR management propositions are made to help organizations coping with these management challenges.  相似文献   
68.
Death is inevitable; yet, not all consumers prepare for death by purchasing end‐of‐life (EOL) products. Using the theory of reasoned action (TRA) and the dual‐process model framework, this study aims to examine the role of emotions and cognitions in influencing consumers' decisions to engage in planning for death. A mixed methodology design was used. Study 1, a qualitative study, uncovered positive and negative emotions and deliberative reasoning that comprise consumers' EOL purchase decision process. Study 2, a quantitative study, confirmed that emotions and deliberations independently and jointly influenced consumers' EOL attitude and behavior and that emotions affected deliberations for both prepaid funerals and wills. Subjective norms outperformed attitude in predicting both products' purchase behavior. These finding supported the dual‐process model of behavior and the TRA in the EOL research context and contributed to the EOL literature by investigating the effects of emotions and deliberations concurrently; thus validating the important role of emotions in influencing EOL planning and purchase. In light of our findings, marketers could, after due cognizance of the morbidity and sensitivity of the topic, develop actionable promotional and segmentation strategies for EOL products and other emotion‐laden, unsought products and service.  相似文献   
69.
This paper offers estimations for the Portuguese path of the Non‐Observed Economy (NOE), in the period 1970–2015, through two seminal approaches: monetary method and the Multiple Indicators Multiple Causes (MIMIC) model. It is observed that the tax burden and social benefits are its main causes. Then, to get a more in‐depth understanding of the phenomenon, it provides a study of the Granger causality between the NOE and the official Gross Domestic Product (GDP), emphasizing the implications of the NOE on the Portuguese economy. Evidence has been found for the existence of bidirectional causality between the NOE and the GDP, suggesting that the formal economy affects the NOE, and conversely that the NOE affects the economic growth.  相似文献   
70.
We propose a novel test to measure market efficiency while estimating the time-varying risk premiums of commodity futures, given that the prices are heteroscedastic. The risk premium is estimated using a state-space model with a Kalman filter modified for heteroscedasticity. Using 79 commodity futures traded on 16 exchanges during the period 2000–2014 and a Monte Carlo simulation, we demonstrate that the proposal produces robust results compared with conventional approaches. The global financial crisis has improved the efficiency and affected the trading volumes of commodity futures, but it has had no effect on the average or the volatility of risk premiums.  相似文献   
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