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   4075篇
  免费   133篇
财政金融   695篇
工业经济   263篇
计划管理   664篇
经济学   915篇
综合类   78篇
运输经济   76篇
旅游经济   91篇
贸易经济   645篇
农业经济   290篇
经济概况   484篇
信息产业经济   1篇
邮电经济   6篇
  2023年   23篇
  2022年   24篇
  2021年   45篇
  2020年   76篇
  2019年   103篇
  2018年   142篇
  2017年   159篇
  2016年   127篇
  2015年   77篇
  2014年   143篇
  2013年   452篇
  2012年   172篇
  2011年   183篇
  2010年   155篇
  2009年   148篇
  2008年   144篇
  2007年   121篇
  2006年   102篇
  2005年   94篇
  2004年   91篇
  2003年   73篇
  2002年   75篇
  2001年   71篇
  2000年   76篇
  1999年   76篇
  1998年   59篇
  1997年   56篇
  1996年   59篇
  1995年   34篇
  1994年   47篇
  1993年   58篇
  1992年   51篇
  1991年   44篇
  1990年   44篇
  1989年   37篇
  1988年   39篇
  1987年   40篇
  1986年   29篇
  1985年   55篇
  1984年   48篇
  1983年   50篇
  1982年   41篇
  1981年   43篇
  1980年   33篇
  1979年   34篇
  1978年   32篇
  1977年   23篇
  1976年   30篇
  1975年   23篇
  1973年   35篇
排序方式: 共有4208条查询结果,搜索用时 437 毫秒
101.
This article revisits a conventional wisdom that inorganic fertiliser use across sub‐Saharan Africa is too low. This expectation that more farmers should be using inorganic fertiliser, and at higher rates, implies it is profitable to use rates higher than observed if farmers are rational expected profit maximisers. We obtain consistent estimates of the effects of applied nitrogen on rice production. We find the yield response to applied nitrogen to be low in the main rice growing farming system. Farmer behaviour is not inconsistent with expected profitability which is limited by a low yield response to applied fertiliser, high transportation costs, and low selling prices for rice in rural areas. In particular, we do not find any farmers for whom applied nitrogen is profitable that are not using fertiliser in the study sample for each of our survey years (2010 and 2012).  相似文献   
102.
The article has analyzed trends in applying advanced manufacturing technologies in Russia in 2005–2014. The dynamics of technical process structures in the context of applications has been considered. The dynamics of the age structure and the structure of technologies in use in annual terms by the place of acquiring has been assessed. The start-up, availability, and removal balance of technologies has been formed, the effective start-up level, and possible ways to improve the state statistical indicators of innovation development have been determined.  相似文献   
103.
Training professionals have long acknowledged the necessity of conducting behavior‐based (Level 3) and results‐based (Level 4) evaluations, yet organizations do not frequently conduct such evaluations. This research examined training professionals' perceptions of the utility of Level 3 and Level 4 evaluations and the factors that facilitate or obstruct their attempts to perform them. The research was conducted using Brinkerhoff's Success Case Method and Gilbert's Behavior Engineering Model as its frameworks. The three key factors identified by study participants as having an impact upon their ability to conduct Level 3 and Level 4 evaluations were the availability of resources such as time and personnel, managerial support (organizational) and expertise in evaluative methodology (individual). The research findings indicated a need to further explore how training professionals interpret Level 3 and Level 4 and how they can better develop their evaluative expertise, which in turn may increase effectiveness in gaining organizational support for evaluation efforts.  相似文献   
104.

This research examines the impact of local and international market factors on the pricing of stock indexes futures in East Asian countries. The purpose of this paper is to present a study of the significant factors that determine the major stock indexes futures’ prices of Hong Kong, Malaysia, Singapore, South Korea and Taiwan. This study first investigates the relationships between Hang Seng Index Futures, KLCI Futures, SiMSCI Futures, KOSPI Futures, Taiwan Exchange Index Futures and local interest rates, dividend yields, local exchange rates, overnight S&P500 index and a newly constructed index, Asian Tigers Malaysia Index (ATMI). 11 years historical data of stock indexes futures and the economic statistics are studied; 10 years in-sample data are used for testing and developing the pricing models, and 1 year out-of-sample data is used for the purpose of verifying the predicted values of the stock indexes futures. Using simple linear regressions, local interest rates, dividend yields, exchange rates, overnight S&P500 and ATMI are found to have significant impact on these futures contracts. In this research, the next period close is predicted using simple linear regression and non-linear artificial neural network (ANN). An examination of the prediction results using nonlinear autoregressive ANN with exogenous inputs (NARX) shows significant abnormal returns above the passive threshold buy and hold market returns and also above the profits of simple linear regression (SLR). The empirical evidence of this research suggests that economic statistics contain information which can be extracted using a hybrid SLR and NARX trading model to predict futures prices with some degree of confidence for a year forward. This justifies further research and development of pricing models using fundamentally significant economic determinants to predict futures prices.

  相似文献   
105.
This paper offers new insights into Beveridge curve analysis by modelling the unemployment–vacancy rate relationship within a Markov regime‐switching environment in which the probabilities of curve‐shifting are determined endogenously by shift factors. Shift factors include structural factors such as labour market participation and net migration, while cyclical variables include GDP growth, the real rate of interest, and labour productivity. This approach enables us to estimate regime‐specific parameters and to assess the role played by these factors in influencing the transition probabilities of switching between regimes. Using New Zealand data, we show that increases in the participation rate have shifted the Beveridge curve inward, while increases in net migration have shifted the curve outward.  相似文献   
106.
In Sub-Saharan Africa, fish ponds are often an integral part of farming systems but have suffered from a lack of viability and sustainability. The present study aims to understand the strategies used by fish farmers to overcome economic and environmental constraints. In 2008 and 2009, fish farmers were surveyed in Central and Western Cameroon, and the fish production systems were classified by cluster analysis. Four broad types were identified according to the complexity of household operations. The development of extensive systems (large-scale and low-input) in rural areas of central Cameroon is induced mainly by abundant available land. For semi-intensive systems in both regions (small-scale and high-input in the Western Region, large-scale and high-input in peri-urban areas of the Central Region), horizontal integration is not sufficient to make fish production profitable and sustainable. More intensive fish farms tend towards vertical integration, in which farmers establish close links with input suppliers. Main causes of low productivity of semi-intensive systems (1–2?t/ha/yr) are both lack of knowledge of fish farming principles by farmers and lack of technical improvement by extension agents and researchers which need to consider the local complexity of farming systems to develop and intensify fish production. The adaptation of development strategies to socio-economic and environmental contexts is a necessity to hope for an increase in fish pond aquaculture production in Africa.  相似文献   
107.
Workload control under continuous order release   总被引:1,自引:0,他引:1  
Workload control is a production planning and control concept specifically designed for complex manufacturing environments. Past research on Workload control has been essentially focused on discrete order release. This means that release of orders to the shop floor takes places on a periodic basis. Continuous order release has been somehow neglected, in spite of its apparent potential for improving system performance, including the reduction of order flow times. This paper presents a simulation study of this order release approach. The study contributes for improving the basis for setting workload norms, selecting the workload control strategy and deciding upon routing alternatives under continuous order release.  相似文献   
108.
The article analyzes the impact of the collapse of world oil prices on the reduction of defense budget, production of weapons, innovative and personnel potential of the defense industry, and on country’s defense capability. Some proposals for the concept of structural changes in the defense industry have been formulated based on experience converting the defense industries in the Soviet Union, the United States, China, and France.  相似文献   
109.
This paper reviews the existing mechanisms of innovative development in the world economy focusing on emerging technologies markets evolution on the example of nanotechnology. The question has been raised of whether nanotechnologies can provide the core of the new technological revolution, and whether these prospects exist for NBIC convergence. In this connection the development of the global market for nano-enabled products following the 2007–2009 crisis and the reliability of the related development forecasts have been assessed. Particular attention has been paid to peculiarities of nanoenabled product market structure and the impact of stagnating R&D costs in the field of nanotechnology.  相似文献   
110.
Financial theory holds that firms can control agency costs through the use of short-term and secured debt. We examine the relation between the use of secured debt and the incentive of the manager to increase the risk of the firm, as measured by vega. We find that firms utilize secured debt to a lesser extent when managerial volatility sensitivity is higher. Our results suggest that these same firms employ short-term debt as the primary tool to control risk-shifting. Managers with a high risk appetite avoid secured debt, but appear to do so without compromising the interests of the shareholders.  相似文献   
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