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41.
20世纪二三十年代,左翼文学在突出革命主题的同时,不可避免地带有颓废情调。一方面表现在内容上的颓废叙述,一方面表现在选题上的颓废倾向。  相似文献   
42.
当代大学生信息素质教育   总被引:3,自引:0,他引:3  
信息素质教育是大学生素质教育的重要组成部分.高校图书馆应开设有关课程,开展一系列教育活动,加强大学生信息能力的培养,大力发展信息专业教育.  相似文献   
43.
目的:探究夏季汽车内瓶装饮用矿泉水开封后的存放时间对水中亚硝酸盐含量及菌落总数的影响.方法:夏季将开封后的瓶装饮用矿泉水放置于汽车内,在第1 d、第3 d、第7 d和第14 d分别测定水中的NO2-含量及菌落总数.检验标准参考《食品安全国家标准饮用天然矿泉水检验方法》(GB 8538—2016)和《生活饮用水标准检验方法微生物指标》(GB/T 5750.12—2006).结果:开封后的瓶装饮用矿泉水在汽车内存放3 d后,菌落总数呈现轻微上升,其菌落总数平均值为7.5 CFU·mL-1、NO2-含量无明显变化;存放7 d后,其菌落总数、NO2-含量呈现急剧上升,其菌落总数平均值为95 CFU·mL-1,NO2-含量为0.125 mg·L-1;存放14 d后,其菌落总数、NO2-含量呈现大幅度上升,其菌落总数平均值为355 CFU·mL-1,NO2-含量为0.254 mg·L-1.结论:开封后的瓶装饮用矿泉水在夏季汽车内的存放时间为7 d时,其菌落数量仍符合《生活饮用水卫生标准》的限值(100 CFU·mL-1)要求,但接近临界值;NO2-含量不符合饮用天然矿泉水标准限值(0.005 mg·L-1),因此开封后的瓶装饮用矿泉水在夏季汽车内的存放时间接近或超过7 d时,不建议直接饮用.  相似文献   
44.
This paper applies the conceptual framework of ‘unbundling’, proposed by Baldwin (2016), to assess the value chain connectivity in Indonesia. Indonesia is a geographically large country, and three different levels of unbundling co-exist. The first unbundling aligns with the industry-wise international division of labour in plantation agriculture, mining, and labour-intensive industries; the second aligns with where the task-wise international division of labour dominates mainly in machinery industries; and the third aligns with where face-to-face costs are reduced by the digital economy. We argue that the further upgrading of unbundling and the more effective use of advanced piecemeal technologies among different levels of unbundling will enable Indonesia to achieve rapid and equitable economic development. Overcoming distance is key for effectively using the mechanics of unbundling. We propose that three key elements are be promoted: enhancement of connectivity, development of the service sector, and improvement of the policy environment.  相似文献   
45.
对全球生产网络背景下产业升级的内涵进行分析,并结合具体评价指标和行业数据对中国汽车产业升级现状进行评价。研究结果表明,中国汽车产业在一定程度上实现了升级,但在发展过程中仍存在很多问题,例如规模效益不明显,创新能力不足等。针对这些问题,从加大整合力度、建立有效的创新激励机制等方面提出相应的对策建议。  相似文献   
46.
The paper proposes endogenous information choice as a channel through which uncertainty affects price dynamics. I consider a rational inattention model with volatility uncertainty and endogenous information processing capability. According to the model, firms' learning and optimal attention exhibits inertia and asymmetry in response to volatility changes. Firms choose to process more information when uncertainty rises, especially about aggregate conditions, and their pricing behavior changes accordingly. Using a Markov‐switching factor‐augmented vector autoregression (MS‐FAVAR), the paper also documents a significant positive correlation between volatility and firms' responsiveness to macro‐ and microlevel shocks, consistent with model predictions.  相似文献   
47.
Previous literature calls for further investigation in terms of precedents and consequences of learning approaches (deep learning and surface learning). Motivation as precedent and time spent and academic performance as consequences are addressed in this paper. The study is administered in a first-year undergraduate course. Results show that the accounting students have a slightly higher score for deep learning compared to surface learning. Moreover, high intrinsic motivation and extrinsic motivation have a significant positive influence on deep learning. Next, deep learning leads to higher academic performance; surface learning on the other hand leads to lower academic performance. The effect of deep learning on performance still holds, when we control for time spent, gender and ability. Consequently we can conclude that a deep learning approach is much more than ‘simply’ spending a lot of time on studying.  相似文献   
48.
The dual risk model assumes that the surplus of a company decreases at a constant rate over time, and grows by means of upward jumps which occur at random times with random sizes. In the present work, we study the dual risk renewal model when the waiting times are phase-type distributed. Using the roots of the fundamental and the generalized Lundberg’s equations, we get expressions for the ruin probability and the Laplace transform of the time of ruin for an arbitrary single gain distribution. Then, we address the calculation of expected discounted future dividends particularly when the individual common gains follow a phase-type distribution. We further show that the optimal dividend barrier does not depend on the initial reserve. As far as the roots of the Lundberg equations and the time of ruin are concerned, we address the existing formulae in the corresponding Sparre-Andersen insurance risk model for the first hitting time, and we generalize them to cover also the situations where we have multiple roots. We do that working a new approach and technique, approach we also use for working the dividends, unlike others, it can be also applied for every situation.  相似文献   
49.
The purpose of this paper is twofold. Firstly, we consider different risk measures in order to determine the solvency capital requirement of a pension fund. Secondly, we illustrate the impact of the time horizon of long-term guarantee products on these capital. We consider a financial market modelled by a common Black–Scholes–Merton model. We neglect the mortality and underwriting risks by assuming that the pension fund is fully hedged against these risks, which allows us to keep understandable and tractable formulæ (the longevity risk will be a part of future researches). A portfolio is built in this market according to different strategies and the pension fund offers a fixed guaranteed rate on a certain time horizon. We begin with well-known static risk measures (value at risk and conditional tail expectation measures) and then we consider their natural dynamic generalization. In order to be time consistent, we consider their iterated versions by a backward iterations scheme. Within the dynamic setting, we show that solvency capital can be expensive and that attention must be paid to the safety level considered.  相似文献   
50.
This study aims to improve the understanding of the underlying mechanism of passenger boarding and alighting processes, as well as its potential influence on train dwell time and train operation. Empirical data collected from one of busiest metro stations in Seoul, Korea, demonstrates the spatial and temporal variation in the passenger service rate, as a result of interference between boarding, alighting, and standing passengers. This study postulates that the level of interference can be associated with the train car occupancy and the proximity of train door to entry points, as waiting passengers tend to cluster near the platform entries. A unique temporal service rate curve is derived from each door location. We introduce Dynamic Time Warping for similarity assessment and clustering. It revealed four groups of train doors showing distinct shapes of curve from each platform. The first cluster includes the train doors located closest to the platform entry points where the initial service rate is drastically impeded by severe inference among passengers. The level of interference gradually diminishes as the door is located farther away from the entry points, but the overall service rate decreases as well. A passenger service time model is derived to include the cluster variable. To test its significance, the prediction capability of the model is presented with and without the cluster variable. The results of this study may be used to guide waiting passengers along the platform to minimize interference and to avoid serious disruption during passenger service time.  相似文献   
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