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   27096篇
  免费   609篇
财政金融   4628篇
工业经济   1818篇
计划管理   4577篇
经济学   6404篇
综合类   511篇
运输经济   178篇
旅游经济   342篇
贸易经济   4747篇
农业经济   1155篇
经济概况   3241篇
信息产业经济   5篇
邮电经济   99篇
  2023年   109篇
  2021年   149篇
  2020年   286篇
  2019年   454篇
  2018年   1104篇
  2017年   1107篇
  2016年   865篇
  2015年   356篇
  2014年   593篇
  2013年   2432篇
  2012年   897篇
  2011年   1370篇
  2010年   1191篇
  2009年   1214篇
  2008年   1134篇
  2007年   1170篇
  2006年   614篇
  2005年   627篇
  2004年   587篇
  2003年   641篇
  2002年   485篇
  2001年   513篇
  2000年   466篇
  1999年   415篇
  1998年   474篇
  1997年   414篇
  1996年   400篇
  1995年   355篇
  1994年   364篇
  1993年   343篇
  1992年   349篇
  1991年   362篇
  1990年   332篇
  1989年   239篇
  1988年   253篇
  1987年   257篇
  1986年   239篇
  1985年   351篇
  1984年   344篇
  1983年   326篇
  1982年   279篇
  1981年   286篇
  1980年   277篇
  1979年   273篇
  1978年   221篇
  1977年   178篇
  1976年   182篇
  1975年   157篇
  1974年   146篇
  1973年   145篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
This paper presents an approach to assessing the efficacy of public spending on research and development in state programs. At present, there is a need to develop a unified approach to the analysis and evaluation of the efficacy of such spending from the perspective of participants in state programs (federal executive bodies). The proposed approach does not allow evaluating the efficacy of public spending on the development of research areas assigned to the authors.  相似文献   
3.
Scholars in our field, Operations and Supply Chain Management (OSCM), are under high pressure to show research productivity. At most schools, this productivity is measured by the number of journal articles published. One possible response to such pressure is to improve research efficiency: publishing more journal articles from each data collection effort. In other words, using one dataset for multiple publications. As long as each publication makes a sufficient contribution, and authors ensure transparency in methods and consistency across publications, generating more than one publication from one data collection effort is possible. The aim of this Notes and Debates article, however, is to draw attention to inappropriate reuse of empirical data in OSCM research, to explain its implications and to suggest ways in which to promote research quality and integrity. Based on two cases of extensive data reuse in OSCM, eighteen problematic practices associated with the reuse of data across multiple journal articles are identified. Recommendations on this issue of data reuse are provided for authors, reviewers, editors and readers.  相似文献   
4.
We extend the entrepreneurship literature to include positive psychological capital — an individual or organization's level of psychological resources consisting of hope, optimism, resilience, and confidence — as a salient signal in crowdfunding. We draw from the costless signaling literature to argue that positive psychological capital language usage enhances crowdfunding performance. We examine 1726 crowdfunding campaigns from Kickstarter, finding that entrepreneurs conveying positive psychological capital experience superior fundraising performance. Human capital moderates this relationship while social capital does not, suggesting that costly signals may, at times, enhance the influence of costless signals. Post hoc analyses suggest findings generalize across crowdfunding types, but not to IPOs.  相似文献   
5.
6.
H. Bause  P. Henn 《Publizistik》2018,63(3):383-405
In 2016, German corporations invested 33.5 billion euros in on-the-job-trainings. Communication trainings, especially those for executives, play an important part in on-the-job-trainings and adult education. This study examines how basics of communication and media studies are used in the praxis of communication trainings. We ask which theories of interpersonal communication are being used in communication trainings for executives and for what reasons trainers choose specific theories. The answer can help us understand how executives view communication processes and which criteria make a theory praticable in the eyes of practitioners.First, we define communication trainings as part of on-the-job training and give an overview of research regarding the use of theories in trainings. Research shows that theories play an important role in communication trainings, but that the trainings lack theoretical depths and complexity. The existing research stems mostly from linguistics; the perspective of communication and media studies is missing. In addition, none of the existing studies considers criteria for a practicable theory.In a second step, the canon of theories of interpersonal communication in communication and media studies is identified via a content analysis of seven textbooks and encyclopedias. Overall, these books present 38 theories of interpersonal communication, but only eight theories are presented in three or more books. These eight theories, among them Symbolic Interactionism (Mead), the Theory of Social Systems (Luhmann) and the Four-Ears-Model (Schulz von Thun), build the canon of theories of interpersonal communication in this study.This canon is the basis for the main part of our study. Sixteen communication trainers were interviewed, using the method of qualitative expert interview. The trainers answered questions regarding their professional background, typical courses of training, their goals in trainings, the role of theories in trainings, requirements of the executives being trained and the exchange between colleagues in the occupational field.Results show that trainers use about 15 to 20% of the training time to convey theoretical basics. The Four-Ears-Model by Schulz von Thun dominates the examined trainings. Scientists regard this communication-psychological model as being rather popular scientific. Still, every interviewed trainer uses it. This finding shows that most trainers regard communicational misunderstandings as a result of the four-dimensional character of a message (Who is the sender? Why is he talking to me like that? What are the facts about? What shall I do, think, feel based on the message?). The Communication Axioms by Watzlawick are used as the second most common approach.Apart from theories of interpersonal communication, the trainers mentioned several psychological methods and approaches with therapeutic traits, like Transaction Analysis (Berne) or Active Listening (Rogers).The explorative findings suggest that the trainers chose the theories they use—especially the Four-Ears-Model and Communication Axioms—because it is easy to interlock these theories and the praxis of communication trainings, because they are comprehensible and easy to use in examples, and because they show the relativity of communication processes. Moreover, trainers use theories to explain human behavior and the sources for misunderstandings.These criteria alone do not explain the trainers’ theory choices, though. It became clear in the interviews that factors of socialization, like advanced training for the trainers, play a major role in influencing their training content. Trainers teach the theories which they themselves learned in further education programs becoming a trainer, and they barely look out for new and/or alternative theories.We recommend that communication trainers look for other theories in communication and media studies, like the Symbolic Interactionism. This theory complies with the trainers’ criteria for good theories. Communication and media scholars on the other hand should work together with educational institutions and advanced training to improve the transfer of their theories into the praxis of communication trainings.  相似文献   
7.
Growing urbanisation in South Africa is reflected in burgeoning Working class and informal township settlements on the fringes of its major towns and cities. Paired with this is an increasing reliance on cash as the primary means of economic transaction, which has in turn stimulated the growth of micro-enterprise business activities within the township context. This article discusses the findings of an eight-township small-area census which occurred between 2010 and 2013 in Cape Town, Johannesburg, Ekurhuleni and Durban townships representing 250 000 residents. The researchers were able to establish the scope and scale of informal food and drink retailing in these localities. Of the 10 049 micro-enterprises located in the study, some 3966 (or 39% of the total) trade in food. These include enterprises in primary production, fresh produce retailing, grocery retailing from house and spaza shops, and informal foodservice enterprises. Food is the basis for much township informal business and plays an important role in making food increasingly affordable and locally accessible, and in creating cash employment. The article builds on the knowledge base of the township informal economy role in bolstering food security needs for the marginalised.  相似文献   
8.
Without guaranteed compensation, granted by the German Renewable Energy Sources Act (Erneuerbare Energien Gesetz/EEG), biogas plants compete with all other plant types on the market for electrical energy. However, exchange-based electricity products do not currently permit an economically viable operation of biogas plants owing to their cost situation.  相似文献   
9.
Making as a design-centered learning activity has recently received significant attention in education. We use literacies—how individuals use representations to learn—to explore the STEM literacy practices of experienced designers and makers. Describing makers’ representational practices in STEM contexts can inform the design of literacy supports for young makers that can encourage their use of representations to connect STEM disciplines and design practices. We interviewed experienced makers to describe one literacy practice central to design: identifying, organizing, and integrating information. Makers enacted this practice within specific making processes—e.g., designing—with the purpose of sourcing and navigating information related to their chosen problems. The research supports efforts to bridge learning while making with learning in schools by positioning STEM literacies as central practices involved in the processes of designing and making.  相似文献   
10.
Objective: This study was to determine if calcium fortification yields a higher price per serving in grocery store products. Researchers compared store brand to national brand grocery products in relation to cost in order to examine if calcium values were similar between store brand and national brand products. Methods: A total of 112 store brand and 211 national brand grocery products were collected from three low (national chain store), middle and high priced (Virginia and North Carolina regional store) grocery venues. Products were compared using price and calcium percentage per serving. ANOVA was used to determine between store brand and national brand for price per serving and calcium content, and between grocery venues. Results: National brand fortified products had a significantly lower mean price per serving when compared to national brand non-fortified products (p = 0.0002). There was no statistical difference between store brand fortified and non-fortified products (p = 0.9256). Low priced store brand products had the lowest mean price per serving ($0.34 ±0.24). Conclusions: This study found store brand products have similar calcium content as national brand products. Product cost was lower at low priced store compared to middle and high priced stores.  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