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   672篇
  免费   17篇
财政金融   88篇
工业经济   14篇
计划管理   93篇
经济学   95篇
运输经济   7篇
旅游经济   22篇
贸易经济   93篇
农业经济   22篇
经济概况   33篇
水利工程   221篇
邮电经济   1篇
  2023年   11篇
  2022年   27篇
  2021年   31篇
  2020年   38篇
  2019年   58篇
  2018年   63篇
  2017年   40篇
  2016年   42篇
  2015年   14篇
  2014年   36篇
  2013年   90篇
  2012年   33篇
  2011年   32篇
  2010年   30篇
  2009年   29篇
  2008年   14篇
  2007年   7篇
  2006年   15篇
  2005年   3篇
  2004年   4篇
  2003年   3篇
  2002年   4篇
  2001年   7篇
  2000年   4篇
  1999年   4篇
  1998年   5篇
  1997年   4篇
  1996年   4篇
  1995年   4篇
  1994年   1篇
  1993年   3篇
  1992年   3篇
  1991年   5篇
  1990年   4篇
  1989年   1篇
  1988年   2篇
  1987年   3篇
  1986年   2篇
  1985年   3篇
  1984年   1篇
  1983年   1篇
  1981年   1篇
  1977年   1篇
  1973年   1篇
  1970年   1篇
排序方式: 共有689条查询结果,搜索用时 625 毫秒
31.
This cross-sectional study was conducted in rural areas of Twiserkan (Toyserkan) County, in Iran, to assess factors associated with home-related injuries among under-five-year children and their mothers’ care regarding injury prevention. Mothers who had their under-five-year-old children injured within a 12-month period were identified from recorded information in Twiserkan Health Center. Then, data were gathered using pre-tested questionnaire and through interview with injured children's mothers. The questions were about characteristics of the children's injuries and their mothers’ care regarding injury prevention, using PRECEDE (Predisposing, Reinforcing, and Enabling Constructs in Educational/Environmental Diagnosis and Evaluation) model with focus on knowledge and attitude; enabling and reinforcing factors; and mothers' preventive behaviours. The study results showed that 197 out of 210 total identified mothers took part in the study. The reported injuries were 11.68%, 39.09%, and 49.24%, respectively, for severe, moderate, and mild cases. Fall was the most frequent injury with 35%. Among PRECEDE model constructs, there was a statistically significant correlation between mothers' knowledge and injury severity among children. Home-related injuries are an important health problem among study population and their prediction and prevention are necessary. Enhancement of mothers’ knowledge can be helpful to improve child injury prevention.  相似文献   
32.
It is expected that the returns and resistance of Islamic mutual funds will be different from conventional mutual funds as the former have limited choices for portfolio diversification. This article analyses the performance of conventional and Islamic unit trusts for the period February 1995 to July 2012 in the Malaysian market, one of the most developed Islamic mutual fund markets. The performance analysis is based on four parameters: (i) risk-adjusted returns of unit trusts; (ii) market timing abilities; (iii) selection performance; and (iv) persistence. The results of this study suggest that the returns of both conventional and Islamic unit trusts have outperformed the market throughout the sample period. The results for market timing and selectivity are mostly the same for both categories of funds. However, Islamic unit trusts seem to have better resistance to market downturn than conventional unit trusts. The results of this research can be used by investors to identify funds or create portfolios that are more suitable for a recessionary scenario and for fund managers to better manage their portfolio performance during times when markets are likely to fall. The findings in this article are highly relevant for policymakers, investors and fund managers to determine policy matters, deciding on investment and marketing strategy for Islamic mutual funds.  相似文献   
33.
Despite knowing the potential effect of social reporting on firms' continuity, there is limited research into the influence of the composition of boards of directors on CSR disclosure. This paper adds to the emerging CSR literature empirical evidence by examining how board composition relates to a firm's social and environmental disclosure as well as the implementation of social policies. Using a sample of FTSE 350 firms for the period 2007–2012, the results show that higher board independence facilitates the conveying of firms' good citizenship image through enhancing societal conscience. The results also show that female participation on boards is favorably affecting CSR engagement and reporting as well as the establishment of ethical policies. Hence, the research suggests that boards with higher female participation and independence boost the legitimacy of CSR reporting. Board gender diversity and independence facilitates directing part of the firm's scarce resources toward value maximizing social projects and subsequent reporting on these. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment  相似文献   
34.
In recent decades, undesirable environmental changes, such as global warming and greenhouse gases emission, have raised worldwide concerns. In order to achieve higher growth rate, environmental problems emerged from economic activities have turned into a controversial issue. The aim of this study is to investigate the effect of financial development on environmental quality in Iran. For this purpose, the statistical data over the period from 1970 to 2011 were used. Also by using the Auto Regression Model Distributed Lag (ARDL), short-term and long-term relationships among the variables of model were estimated and analyzed. The results show that financial development accelerates the degradation of the environment; however, the increase in trade openness reduces the damage to environment in Iran. Error correction coefficient shows that in each period, 53% of imbalances would be justified and will approach their long-run procedure. Structural stability tests show that the estimated coefficients were stable over the period.  相似文献   
35.
The paper investigates the impact of the pre-acquisition evaluation of target firms on the performance of cross border acquisitions using data from a sample of acquisitions made by UK firms. The findings provide reasonable support for organizational learning theory, suggesting that the more the acquiring firm learns about the target firm then the better will be the acquisition performance. Specifically, we find support for the hypothesis that thorough evaluation of the strategic and cultural fit positively influences cross border acquisition success. Further, the analysis reveals that detailed evaluation of the target firm's employee and business capability improves acquisition performance. The managerial implications of the findings and directions for future research are also discussed.  相似文献   
36.

Since the United Nations’ establishment of the Millennium Development Goals (MDGs) in 2000 the world has observed an increasing trend in foreign aid provided by more affluent countries to developing nations. This paper examined whether foreign aid (total foreign aid and health sector aid) has been effective in improving the health of citizens in recipient nations since establishment of the MDGs. Five facets of population health were examined: infant mortality, life expectancy, the annual death rate, and immunizations against measles and diphtheria. Using a panel data set covering 90 developing countries, observed annually over 2001–2015, fixed-effects multivariate regressions with alternative specifications were estimated for each of these measures. The findings reveal that foreign aid has had little to no effect on population health since 2000. We found some evidence that foreign aid has improved life expectancy in developing countries, however, the effect is very small. In light of these findings, continued monitoring of the relationship between foreign aid and health outcomes would be both valuable and prudent.

  相似文献   
37.
全面建设小康社会,区域难点在民族地区,城乡难点在农村。少数民族地区的农牧区处于此二者的交汇处,属我国全面建设小康社会的难中之难。全面建设小康社会这一宏伟目标能否顺利实现,关键在于民族地区农牧区居民收入与生活水平是否能达到小康标准。从民族地区农村居民收入的增长趋势看,现阶段很难达到目标。因此,未来的关键是下大力气增加农牧民收入,并加快增长速度。  相似文献   
38.
This article used a data set containing information on 1267 households from Kuwait to investigate the determinants of demand for medical care services by examining households’ out-of-pocket expenses. To deal with the problems associated with households’ health expenditure data, a two-part model (TPM) was estimated. Given Kuwait’s demographic composition, the model was estimated for full sample, nationals only and expatriates only. Prior to estimating the model, tests were conducted to select a transformation that reduces problems associated with heteroscedasticity and non-normality of the errors. In addition, tests were performed to determine if differences in the estimated coefficients across population groups were statistically significant.  相似文献   
39.
This article presents the empirical Bayes method for estimation of the transition probabilities of a generalized finite stationary Markov chain whose ith state is a multi-way contingency table. We use a log-linear model to describe the relationship between factors in each state. The prior knowledge about the main effects and interactions will be described by a conjugate prior. Following the Bayesian paradigm, the Bayes and empirical Bayes estimators relative to various loss functions are obtained. These procedures are illustrated by a real example. Finally, asymptotic normality of the empirical Bayes estimators are established.  相似文献   
40.
The mechanisms used to deliver agricultural beneficial management practices (BMPs) can influence the performance of these policies. Research has suggested that agri‐environmental instruments targeted based on specific economic or environmental characteristics can improve policy performance. Using a case study approach, we evaluate the relative performance of different mechanisms to target subsidized water retention pond BMPs to reduce phosphorus (P) runoff in an agriculture dominated subwatershed within the Lake Winnipeg watershed in southern Manitoba. The water retention pond BMPs were targeted based on estimated establishment costs (cost targeting), total phosphorus removal from surface water (benefit targeting), and pond‐specific benefit–cost ratios. The targeting was simulated using predictions of retention pond‐specific P removal from an adapted hydrology model and site‐specific pond construction and land opportunity costs assembled in a geographic information system database. Targeting of water retention pond BMPs has an impact on the cost effectiveness of the policy delivery with benefit–cost targeting being the most cost‐effective approach. Water retention ponds providing higher P removal at lower cost were smaller in size and on land previously used for the production of lower value crops. Le ciblage économique des pratiques de gestion bénéfiques en agriculture pour remédier au ruissellement du phosphore au Manitoba Les mécanismes utilisés pour livrer des pratiques de gestion bénéfiques (PGB) peuvent influencer la performance de ces politiques. Des études suggèrent que le ciblage d'instruments agroenvironnementaux basé sur des caractéristiques économiques ou environnementales précises peut améliorer la performance des politiques. Au moyen d'études de cas, nous évaluons la performance relative de divers mécanismes pour cibler les PGB des bassins de rétention d'eau subventionnés pour réduire le ruissellement de phosphore (P) dans un sous‐bassin du bassin du Lac Winnipeg au sud du Manitoba. Les PGB du bassin de rétention des eaux ont été ciblées en fonction des coûts estimés d'établissement (ciblage des coûts), de l′élimination totale du phosphore de la surface de l'eau (ciblage des bénéfices), et des ratios avantages‐coûts liés au bassin. Le ciblage fut simulé au moyen de prédictions du taux de suppression de P spécifique à chaque bassin de rétention obtenues à partir d'une adaptation d'un modèle hydrologique et d'une base de données d'un système d'information géographique (SIG) contenant les sites de chaque bassin de rétention et le coût d'opportunité du terrain. Le ciblage des PGB des bassins de rétention d'eau a un impact sur la rentabilité de la mise en ?uvre de politiques, le ciblage coût‐avantages étant l'approche la plus rentable. Les bassins de rétention d'eau ayant le plus haut taux d'élimination de P à moindre coût s'avéraient plus petits et sur des terrains ayant servi, auparavant, à la production de cultures de moindre valeur.  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