首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1224篇
  免费   79篇
财政金融   199篇
工业经济   66篇
计划管理   216篇
经济学   366篇
综合类   10篇
运输经济   17篇
旅游经济   25篇
贸易经济   295篇
农业经济   19篇
经济概况   87篇
信息产业经济   1篇
邮电经济   2篇
  2024年   8篇
  2023年   23篇
  2022年   10篇
  2021年   25篇
  2020年   39篇
  2019年   41篇
  2018年   96篇
  2017年   85篇
  2016年   84篇
  2015年   52篇
  2014年   65篇
  2013年   181篇
  2012年   64篇
  2011年   53篇
  2010年   56篇
  2009年   62篇
  2008年   48篇
  2007年   32篇
  2006年   21篇
  2005年   19篇
  2004年   24篇
  2003年   17篇
  2002年   16篇
  2001年   14篇
  2000年   12篇
  1999年   14篇
  1998年   6篇
  1997年   11篇
  1996年   8篇
  1995年   10篇
  1994年   10篇
  1992年   6篇
  1989年   2篇
  1988年   3篇
  1987年   2篇
  1986年   3篇
  1985年   6篇
  1984年   7篇
  1983年   5篇
  1982年   2篇
  1981年   6篇
  1980年   7篇
  1979年   13篇
  1978年   4篇
  1977年   7篇
  1976年   2篇
  1975年   3篇
  1968年   2篇
  1961年   2篇
  1958年   3篇
排序方式: 共有1303条查询结果,搜索用时 546 毫秒
21.
The ease with which 3D CAD models may be modified and reused are two key aspects that improve the design-intent variable and that can significantly shorten the development timelines of a product. A set of rules are gathered from various authors that take different 3D modelling strategies into account. These rules are then applied to CAD strategic-knowledge learning methodology and included in 3D CAD modelling exercises for students following the degree in mechanical engineering at the University of Burgos (Spain). The experiment was conducted in two groups with a total of 75 students. The design-intent rules were introduced in the different exercises that the teacher explained in both the theoretical and the practical classes. In addition, a summary of the different design rules in each of the practical exercises was explained in the practical classes in only one of the groups. The experimental results, reported in this paper, tested the influence of these summaries on overall improvements in 3D modelling and on the design-intent variable, which is subdivided into four sections: skeleton, structures, alterations and constraints. The use of the summaries of the design intent rules led to statistically significant improvements in 3D modelling in the experimental group, in comparison with the group of students to whom those summaries were not explained.  相似文献   
22.
23.
Aims: To model direct medical costs associated with reductions in cardiovascular disease (CVD) events in T2DM patients reported in the CANVAS and EMPA-REG trials, which assessed the cardiovascular safety of canagliflozin and empagliflozin, respectively.

Materials and methods: Costs were modeled from a US managed care organization (MCO) perspective for the CVD outcomes included in both trials: three-point major adverse cardiovascular event (MACE) and its components (cardiovascular-related death, nonfatal myocardial infarction, nonfatal stroke), as well as heart failure requiring hospitalization. The rate of CVD events averted (difference between study drug and placebo) was projected to the portion of an MCO T2DM population matching the respective trial’s inclusion criteria. A targeted literature search for paid amounts directly associated with each CVD event provided the unit costs, which were applied to the projected number of events averted, to calculate costs avoided per member per year (PMPY). One-way sensitivity analyses were performed on events averted, unit costs, and percentages of trial-applicable patients.

Results: Based on three-point MACE events averted, costs avoided PMPY of $6.17 (range: $1.27–$10.94) for CANVAS and $2.75 ($0.19–$4.83) for EMPA-REG were estimated. Costs avoided for individual components of MACE ranged from $0.77 to $3.84 PMPY for CANVAS and from -$0.97 (additional costs) to $1.54 for EMPA-REG. PMPY costs avoided for heart failure were $2.72 for CANVAS and $1.32 for EMPA-REG.

Limitations and conclusions: Models assumed independent, non-recurrent outcomes and were restricted to medical costs directly associated with the trial-reported events. The reductions in CVD events in T2DM patients reported for both CANVAS and EMPA-REG project to a positive cost avoidance for these events in an MCO population. The analysis did not include an assessment of the impact on total cost, as the costs associated with adverse events, drug utilization or other clinical outcomes were not examined.  相似文献   

24.
Small Business Economics - This paper analyzes the effect of bank market power on the financial constraints of small and medium-sized enterprises (SMEs) through the study of borrower...  相似文献   
25.
The purpose of this study is to examine how credit rating agencies’ decisions impact the stock market using a systematic and quantitative review of existing empirical studies. Specifically, we employ a meta‐regression analysis (MRA) to investigate the extent and nature of the effect of rating agencies’ decisions on the stock market. We survey 62 studies published between 1978 and 2015. Our first finding is that the cumulative average abnormal returns calculated from this empirical literature are affected by publication bias. After controlling for publication bias, the main findings of our meta‐analysis indicate that negative rating decisions cause statistically significant negative abnormal returns. This evidence suggests an informational effect. Our results also indicate that positive rating decisions do not have a significant effect. Finally, the MRA results reveal the importance of several factors related to primary study design, as well as to the nature of the data.  相似文献   
26.
Se exploran los determinantes a corto plazo del emparejamiento entre oferta y demanda de trabajo identificando los desplazamientos de la curva de Beveridge en doce países de la OCDE entre el primer trimestre de 2000 y el cuarto trimestre de 2013. Mediante tres metodologías complementarias (examen visual, técnicas de cointegración y estimaciones no lineales), observamos que el crecimiento de la población activa, la legislación de protección del empleo y las políticas activas de mercado de trabajo (incentivos a la creación de empresas, programas de trabajo compartido) favorecen el emparejamiento, mientras que los niveles de instrucción intermedios, el desempleo de larga duración y las políticas pasivas (prestaciones por desempleo, fiscalidad del trabajo) lo dificultan.  相似文献   
27.
In contemporary African cities, dressing well and wearing exclusive garments has become crucial for people in search of identity, distinction and individuality. The research presented in this article, situated at disciplinary intersections of cultural studies, fashion practices and sustainability, provides a case study of African tailors conducted in Maputo and Lisbon, with a special focus on identity building of African immigrants in Portugal. However, the role of tailors in this acculturation process has been ignored in the consumption approach to creative cities. This study is therefore also a reaction to the mainly Western world of regular couture, and to ‘creative city materials’ that focus on consumption. Instead, we emphasize the importance of African tailors who de facto shape urban experiences—visually incrementing practices—that are fundamental to the comprehension of sartorial culture, while we also allude to the complex intersections between local and global markets. In the first part of this article we describe a semi-ethnographic study among tailors in Maputo and Lisbon. The second part presents a participatory action approach that entailed developing an educational programme for African tailors where culture and creativity meet. This programme empowered tailors to tap into their cultural knowledge on tailoring and their awareness of community identity. In our study we argue that the idea of creative cities and their creative economy should be approached from a cultural perspective, by building awareness of the importance of local creative classes instead of focusing on importing those classes.  相似文献   
28.
29.
This paper attempts to find a robust method of measuring competition when firms' operational activities are subject to frictions. The first part theoretically tests the indicative quality of two competition measures, the price‐cost margin (PCM) and the profit elasticity, in a model of monopolistic competition. The second part studies the empirical performance of the indices for a panel of Ukrainian manufacturing firms. This study offers a new approach to measuring profit elasticity that relies on structural estimation of a production function. The estimation methodology retrieves a productivity index that is adjusted to imperfect competition. The proposed method of measuring profit elasticity is found to be robust to frictions, but the PCM and traditional profit elasticity are biased, especially when the intensity of competition is low. Empirical findings show that competition exhibits a significantly positive correlation with aggregate productivity performance, while its impact on firm productivity is nonlinear.  相似文献   
30.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号