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   1196篇
  免费   30篇
  国内免费   2篇
财政金融   184篇
工业经济   36篇
计划管理   515篇
经济学   237篇
综合类   36篇
运输经济   25篇
旅游经济   47篇
贸易经济   65篇
农业经济   25篇
经济概况   58篇
  2024年   5篇
  2023年   58篇
  2022年   51篇
  2021年   62篇
  2020年   82篇
  2019年   79篇
  2018年   50篇
  2017年   49篇
  2016年   36篇
  2015年   26篇
  2014年   81篇
  2013年   122篇
  2012年   65篇
  2011年   89篇
  2010年   38篇
  2009年   43篇
  2008年   45篇
  2007年   40篇
  2006年   28篇
  2005年   27篇
  2004年   18篇
  2003年   32篇
  2002年   12篇
  2001年   9篇
  2000年   8篇
  1999年   4篇
  1998年   8篇
  1997年   7篇
  1996年   7篇
  1995年   3篇
  1993年   3篇
  1992年   4篇
  1988年   3篇
  1987年   3篇
  1986年   3篇
  1985年   9篇
  1984年   9篇
  1983年   4篇
  1982年   5篇
  1981年   1篇
排序方式: 共有1228条查询结果,搜索用时 15 毫秒
61.
文章介绍了红水河岩滩水电站水文预报的方案、内容及作业方法。  相似文献   
62.
We investigate the relative impact of internal Delphi process factors - including panelists' degree of confidence, expertise, majority/minority positioning - and an external factor, richness of feedback - on opinion change and subsequent accuracy of judgmental forecasts. We found that panelists who had low confidence in their judgmental forecast and/or who were in a minority were more likely to change their opinion than those who were more confident and/or in a majority. The addition of rationales, or reasons, to the numeric feedback had little impact upon panelists' final forecasts, despite the quality of panelists' rationales being significantly positively correlated with accurate forecasts and thus of potential use to aid forecast improvement over Delphi rounds. Rather, the effect of rationales was similar to that of confidence: to pull panelists towards the majority opinion regardless of its correctness. We conclude that majority opinion is the strongest influence on panelists' opinion change in both the ‘standard’ Delphi, and Delphi-with-reasons. We make some suggestions for improved variants of the Delphi-with-reasons technique that should help reduce majority influence and thereby permit reasoned arguments to exert their proper pull on opinion change, resulting in forecast accuracy improvements over Delphi rounds.  相似文献   
63.
Technology has been the driving force of development for knowledge-based economies. As competition in technology innovation among nations becomes more intense, there is a growing need for improved judgment, evaluation and prediction of scientific technology capacity in order to enhance national competitiveness. Until now, a country's technology level has been evaluated on a relative basis by comparing it with that of the country with the world's best technology. However, this kind of static methodology makes the interpretation of results unclear and makes time series analysis difficult. One of the most important limitations of this methodology is that it cannot be used to establish a strategy to improve the technology level. This paper examines the methodological problems of technology level evaluation and develops a dynamic methodology by applying the technology growth curve model. We also analyze the real technology level by using a new model application and review the relevance of this method. Finally, we discuss how to use the results in order to create a dynamic technology strategy.  相似文献   
64.
Logistic and power law methodologies for both retrospective and prospective analyses of extended time series describing evolutionary growth processes, in environments with finite resources, are confronted. While power laws may eventually apply only to the early stages of said growth process, the Allee logistic model seems applicable over the entire span of a long range process. On applying the Allee logistic model to both the world population and the world gross domestic product time series, from 1 to 2008 AD, a projection was obtained that along the next few decades the world should experience a new economic boom phase with the world GDP peaking around the year 2020 and proceeding from then on towards a saturation value of about 142 trillion international dollars, while the world population should reach 8.9 billion people by 2050. These results were then used to forecast the behavior of the supply and consumption of energy and food, two of the main commodities that drive the world system. Our findings suggest that unless the currently prevailing focus on economic growth is changed into that of sustainable prosperity, human society may run into a period of serious economical and social struggles with unpredictable political consequences.  相似文献   
65.
Patent indicators for monitoring convergence - examples from NFF and ICT   总被引:2,自引:0,他引:2  
The blurring of boundaries between hitherto distinct scientific disciplines, technologies or markets is a common and powerful phenomenon. Concentrating on monitoring convergence through patent indicators, we discuss convergence with examples from the area of Nutraceuticals and Functional Foods (NFF)/Cosmeceuticals as well as information technologies, consumer electronics, and telecommunications (ICT). We analyze 7455 scientific and patent references on phytosterols with the aid of SciFinder Scholar and 3836 documents employing STN AnaVist. Furthermore, we test an IPC co-classification based approach on 859,469 ICT-related and 341,846 NFF-related patents. Our results show clear indications for convergence and a proof of principle for our monitoring concept. Academics may better evaluate environmental parameters, like cases of convergence, influencing companies' actions. Implications for practitioners are based on a more reliable assessment prior to the forming of strategic alliances or mergers and acquisitions. This could help avoid costly adventures such as the mergers and acquisitions seen in ICT.  相似文献   
66.
This work presents a novel gray-based cost efficiency (GCE) model that integrates the gray forecasting model into a two-factor cost efficiency curve model for renewable energy (RE) technologies and identifies the optimal forecasting model for power generation cost of RE technologies. The analytical framework of proposed GCE model improves short-term prediction of power generation cost, and can be applied during the early developmental stages for RE technologies. Empirical analysis is based on wind power data for Taiwan. Time lag of knowledge stock was simulated to represent the actual relationship between R&D expenditures and cost reductions in power generation by knowledge stock. Analytical results demonstrate the GCE model is a useful tool to quantify the influences of cost reductions in power generation. The implications of analytical results are that institutional policy instruments play an important role in RE technologies achieving cost reductions and market adoption. The proposed GCE model can be applied to all high-technology cases, and particularly to RE technologies. The study concludes by outlining the limitations of the proposed GCE model and directions for further research.  相似文献   
67.
基于案例推理的非常规突发事件资源需求预测   总被引:2,自引:0,他引:2  
王晓  庄亚明   《华东经济管理》2011,25(1):115-117
近年来非常规突发事件频繁发生,严重危害了人民的生命财产安全,而如何及时预测灾害发生后的资源需求成为一个重要课题。文章提出了一种精确的预测方法,将模糊集理论,神经网络Hebb学习规则和多元线性回归与案例推理法相结合。这种方法很好地解决了非常规突发事件资源需求预测这类信息不完备、不精确问题,能够比较准确的作出资源的需求预测。该模型对灾害资源需求预测具有一定的参考价值。  相似文献   
68.
The Asian financial crisis has drawn worldwide attention because of its significant economic impact on local economics, especially on the economy of a tourism‐dependent destination. Unfortunately, there have been very few articles about the relationship of the Asian financial crisis and tourism demand forecasting. This relative lack of prior studies on the Asian financial crisis and tourism demand forecasting is particularly true in the context of Hong Kong. This article reports on a study that utilized officially published data to test the accuracy of forecasts of Japanese demand for travel to Hong Kong, measured in terms of the number of Japanese tourist arrivals. Seven commonly‐used tourism forecasting techniques were used to determine the forecasting accuracy. The quality of forecasting accuracy was measured in five dimensions. Experimental results indicated mixed results in terms of forecasting accuracy. Overall, artificial neural network outperformed other techniques in three of the five dimensions.  相似文献   
69.
Abstract

Numerous outdoor recreation forecasting studies have included household characteristics as well as aspects of the recreation facilities and accessibility. Only a few studies, however, have included in the prediction equation any measure of the effects of urban milieu on behavior. Four commonly cited surrogates of urban milieu are used to cluster the cities of Illinois into three relatively homogeneous groups of environments. Regression analyses are then undertaken using individual household data, aspects of the recreation facilities patronized by the households, participation, and distance and travel time estimates. Comparisons of the regression analyses indicate that, as a concept, milieu is an important predictor of both the volume of recreation participation and salient features of recreation facilities.  相似文献   
70.
A variety of methods and ideas have been tried for electricity price forecasting (EPF) over the last 15 years, with varying degrees of success. This review article aims to explain the complexity of available solutions, their strengths and weaknesses, and the opportunities and threats that the forecasting tools offer or that may be encountered. The paper also looks ahead and speculates on the directions EPF will or should take in the next decade or so. In particular, it postulates the need for objective comparative EPF studies involving (i) the same datasets, (ii) the same robust error evaluation procedures, and (iii) statistical testing of the significance of one model’s outperformance of another.  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