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   393篇
  免费   35篇
  国内免费   4篇
财政金融   44篇
工业经济   22篇
计划管理   107篇
经济学   101篇
综合类   38篇
运输经济   6篇
旅游经济   4篇
贸易经济   63篇
农业经济   17篇
经济概况   30篇
  2023年   8篇
  2022年   3篇
  2021年   9篇
  2020年   16篇
  2019年   21篇
  2018年   24篇
  2017年   20篇
  2016年   24篇
  2015年   13篇
  2014年   19篇
  2013年   56篇
  2012年   23篇
  2011年   39篇
  2010年   24篇
  2009年   19篇
  2008年   15篇
  2007年   18篇
  2006年   18篇
  2005年   9篇
  2004年   12篇
  2003年   6篇
  2002年   8篇
  2001年   4篇
  2000年   4篇
  1999年   3篇
  1998年   4篇
  1997年   4篇
  1996年   1篇
  1995年   3篇
  1992年   1篇
  1991年   1篇
  1988年   3篇
排序方式: 共有432条查询结果,搜索用时 31 毫秒
1.
Vietnam has undergone market reforms over the last three decades; and as a consequence, the coffee sector has become increasingly market‐driven. The success of the government's liberalisation policies in terms of market efficiency is investigated by examining the transmission of both positive and negative price changes for Robusta coffee between export and farmgate prices. We used a threshold vector error correction model and high‐frequency daily data. The primary result here is that of a symmetric price transmission between export and farm‐level prices. This result holds when tested with weekly price data, derived from the daily data. Farmgate prices respond faster to decreases than increases in export prices when the long‐run deviation exceeds a certain threshold. These price changes are transmitted within several days. This research also confirms the importance of transaction costs, and other price frictions mostly ignored in prior analyses for coffee.  相似文献   
2.
3.
In order to account for currency substitution, the exchange rate is included in the demand for money. More recent studies have demonstrated that exchange rate changes could have asymmetric effects on the demand for money or domestic currency. In this paper, we consider the experiences of 18 African countries and show that in most countries, indeed exchange rate changes have short-run asymmetric effects on the demand for money. However, short-run effects translate to long-run asymmetric effects only in a limited number of African countries.  相似文献   
4.
在雷达目标跟踪中,系统量测信息通常在球坐标系下获得。为了采用经典卡尔曼滤波算法实现有效目标跟踪,通常采用量测转换方法将非线性量测信息转换到直角坐标系中。针对传统量测转换方法基于量测值计算转换误差统计特性而导致的估计结果有偏问题,提出了一种基于预测值的量测转换方法,并将其与卡尔曼滤波算法相结合,获得了一种基于预测值量测转换的卡尔曼滤波跟踪算法。仿真结果表明,与现有的基于量测转换的卡尔曼滤波算法相比,该算法能在不提高运算量的情况下有效改善目标跟踪效果,跟踪精度提升约20%。  相似文献   
5.
为了抑制脉冲噪声对电力线正交频分复用(OFDM)通信系统的影响,最常用的方法之一是在接收端OFDM解调器之前前置一个置零非线性单元,即传统置零法。然而,由于引入了非线性失真,其性能并不理想。针对传统置零法引起的非线性失真问题,提出了一种基于迭代消除非线性失真的改进置零法。首先,对接收到的时域OFDM信号进行脉冲噪声检测和置零处理;然后,在频域利用已检测的符号来重构时域置零处理引入的非线性失真,并通过迭代提高重构的准确性;最后,从频域接收信号中减去重构的非线性失真。仿真结果表明,所提改进算法与传统置零法相比,有非常大的性能提升,增强了电力线OFDM通信系统对脉冲噪声的抵抗能力。  相似文献   
6.
Public bike-sharing systems (BSSs) are an emerging mode of transportation introduced by municipalities to solve congestion problems in metropolitan areas, especially when integrated with other types of transportation. In the last years, the number of public bike-sharing services has been constantly on the rise all over the world, and generally the overall satisfaction with them is high. However, satisfaction with public services is driven by mechanisms that can differ from those in the private sector. It is important to establish to what extent a high satisfaction is genuine or simply ephemeral. Even “old” public services (like public transportation) become “gold” when accompanied by the introduction of new technologies. In this paper we analyze this phenomenon using data from a satisfaction web-survey conducted among customers of the public BSS “BikeMi” in Milan, Italy, in a period when mobile technologies have been introduced to speed up the service. On analyzing the responses to satisfaction questions using simple summary statistics, the level of satisfaction resulted very high. However, our aim was to look for potential “darker” sides of the service by detecting possible hidden satisfaction components. For this purpose, we used the Nonlinear Principal Components Analysis, which is particularly powerful in this context. A simple textual analysis was also performed as a validating test. Results from our analysis indicated that satisfaction is flawed by a set of factors like the mechanics of the bikes, the picking and dropping system, and the apps used to organize the service. Less concern was detected for more general aspects of the service.  相似文献   
7.
This paper investigates nonlinearities in the dynamics of real exchange rates. We use Monte Carlo simulations to establish the size properties of the Teräsvirta-Anderson test, when the dynamics of the real exchange rate is influenced by an exogenous process. In addition, we show that a modified nonlinearity test, which includes additional right-hand-side variables, performs much better than the original in both Monte Carlo exercises and in the actual data on 1431 bilateral real exchange rate series. Finally, we investigate the dynamics of the real exchange rate for both developed and developing countries using the modified test for the recent floating period. In general, the results find a greater incidence of nonlinear dynamics for developing country real exchange rates.  相似文献   
8.
This article uses a smooth transition regression (STR) model to research the income elasticity of the health care expenditure of China’s urban residents in the 1990–2013 period. The results demonstrate that if the real income of China’s urban residents that lags a period is taken as a transition variable, urban residents’ health expenditure follows an LSTR1 nonlinear two-regime model. Here, the income elasticity of health care expenditure of China’s urban residents is 1.4919 in 1990–2002 and 1.2216 in 2003–2013. Overall, the income elasticity of health care of China’s urban residents is greater than 1, indicating that health care is a luxury.  相似文献   
9.
ABSTRACT

We propose a new approach for tracing the so-called ‘value-added-(re)distribution-important coefficients’ (in short the VARDI coefficients) in a world input–output model. From the perspective of a selected group of economies, VARDI coefficients may be defined as those elements in world input–output matrix in the case of which a small change in their levels leads to the maximization of a share of this group of economies in value added in global value chains. Due to the rapid development of the World Input Output Database, this approach may be easily applied in empirical research to different groups of countries and sectors in world IO models. In an illustrative empirical case study, we use the new approach in order to answer a question regarding what the main directions of the future macroeconomic policy of the U.S. could be in order to ensure the maximization of the country’s share in global value added.  相似文献   
10.
The service sector in India has emerged as the ‘new engine of growth’ with an increasing share in output and exports. In this paper we analyse the effect of real exchange rate movements on service exports of India, incorporating goods exports, financial development, FDI inflows, world demand and the role of globalization as drivers. We find that while traditional service exports are negatively and significantly affected by the real exchange rate movements, the modern service exports are negatively but not significantly affected. By applying the asymmetric cointegration approach, the results also confirm the non-existence of any asymmetric relationship between the real exchange rate and service exports in India. Further, the results also show that the supply augmenting and demand-side factors are more dominant than the exchange rate to affect service exports from India.  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