全文获取类型
收费全文 | 15003篇 |
免费 | 4333篇 |
国内免费 | 137篇 |
专业分类
财政金融 | 882篇 |
工业经济 | 1847篇 |
计划管理 | 2471篇 |
经济学 | 3997篇 |
综合类 | 1460篇 |
运输经济 | 126篇 |
旅游经济 | 68篇 |
贸易经济 | 3860篇 |
农业经济 | 3058篇 |
经济概况 | 1693篇 |
邮电经济 | 11篇 |
出版年
2024年 | 179篇 |
2023年 | 423篇 |
2022年 | 389篇 |
2021年 | 500篇 |
2020年 | 614篇 |
2019年 | 1008篇 |
2018年 | 786篇 |
2017年 | 869篇 |
2016年 | 780篇 |
2015年 | 890篇 |
2014年 | 1089篇 |
2013年 | 1234篇 |
2012年 | 1452篇 |
2011年 | 1179篇 |
2010年 | 1193篇 |
2009年 | 1119篇 |
2008年 | 874篇 |
2007年 | 995篇 |
2006年 | 868篇 |
2005年 | 756篇 |
2004年 | 539篇 |
2003年 | 360篇 |
2002年 | 247篇 |
2001年 | 185篇 |
2000年 | 135篇 |
1999年 | 76篇 |
1998年 | 77篇 |
1997年 | 67篇 |
1996年 | 50篇 |
1995年 | 38篇 |
1994年 | 44篇 |
1993年 | 48篇 |
1992年 | 67篇 |
1991年 | 89篇 |
1990年 | 30篇 |
1989年 | 33篇 |
1988年 | 15篇 |
1987年 | 9篇 |
1985年 | 13篇 |
1984年 | 9篇 |
1983年 | 12篇 |
1982年 | 20篇 |
1981年 | 7篇 |
1979年 | 8篇 |
1978年 | 8篇 |
1973年 | 7篇 |
1972年 | 7篇 |
1971年 | 6篇 |
1969年 | 9篇 |
1963年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Rosa M. Barriga Eugenia P. Vanek Katherine H. Mann Arnold Reisman Lawrence T. Kent 《Socio》1990,24(4):273-283
The simulation problem is one of the most commonly used formats in computer-assisted instruction (CAI). In medical education, a patient simulation problem is known as a patient management problem (PMP). A number of computerized PMP systems are currently available. However, to date, there is no record of PMP systems having been developed using artificial intelligence. This is noteworthy since artificial intelligence techniques could help in the generation of more effective and intelligent instructional systems.
This paper analyzes and evaluates existing instructional simulation software in clinical medicine in terms of effective educational design attributes. Components of effective PMP systems thus identified are incorporated into a computerized instructional system which uses artificial intelligence techniques for teaching problem-solving and diagnostic skills to undergraduate medical students. 相似文献
82.
83.
本文介绍了利用单片机如何实现智能环形线圈车辆检测器,讨论了此类检测器的软硬件设计要点。给出了相应的接口电路。 相似文献
84.
85.
86.
87.
88.
89.
90.
Joshua J. Lewer Hendrik Van den Berg 《American journal of economics and sociology》2007,66(4):765-794
A bstract . Despite interest in the influence of religion on economic activity by early economists like Adam Smith, modern economists have done little research on the subject. In light of the apparent religious fervor in many parts of the global economy, economists' seeming lack of interest in studying how religious cultures enhance or retard the globalization of economic activity is especially surprising. This article makes a contribution toward filling this void by examining how religion affects international trade. Specifically, we examine whether the sharing of religious cultures enables the formation of exchange networks that can overcome the failure or nonexistence of other social and economic institutions necessary for completing complex international transactions. We apply an expanded gravity model of international trade to control for a variety of factors that determine trade, and we use two recently developed regression methods, scaled OLS and nonlinear least squares, to exploit the model to its fullest. We find that the sharing of Buddhist, Confucian, Hindu, Eastern Orthodox Catholic, and Protestant cultures by people in different countries has a significantly positive influence on bilateral trade, all other things equal. The sharing of Roman Catholic culture has a significantly negative influence on bilateral trade, and the sharing of Islamic and Judaic cultures neither promotes nor discourages international exchange. These results suggest that some religious cultures are more conducive than others for forming international trade networks. 相似文献