全文获取类型
收费全文 | 396篇 |
免费 | 2篇 |
专业分类
教育 | 290篇 |
科学研究 | 49篇 |
各国文化 | 6篇 |
体育 | 15篇 |
文化理论 | 1篇 |
信息传播 | 37篇 |
出版年
2021年 | 8篇 |
2020年 | 4篇 |
2019年 | 17篇 |
2018年 | 19篇 |
2017年 | 23篇 |
2016年 | 17篇 |
2015年 | 8篇 |
2014年 | 12篇 |
2013年 | 76篇 |
2012年 | 15篇 |
2011年 | 16篇 |
2010年 | 17篇 |
2009年 | 17篇 |
2008年 | 10篇 |
2007年 | 7篇 |
2006年 | 13篇 |
2005年 | 9篇 |
2004年 | 2篇 |
2003年 | 8篇 |
2002年 | 5篇 |
2001年 | 4篇 |
2000年 | 9篇 |
1999年 | 5篇 |
1998年 | 4篇 |
1997年 | 11篇 |
1996年 | 6篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 7篇 |
1991年 | 2篇 |
1990年 | 5篇 |
1989年 | 4篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 6篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1974年 | 1篇 |
1970年 | 1篇 |
1969年 | 2篇 |
1968年 | 1篇 |
1938年 | 1篇 |
排序方式: 共有398条查询结果,搜索用时 15 毫秒
391.
Inventing is a recombinant process that involves searching and recombining different streams of knowledge. The value of invention is associated with not only how many prior inventions are considered, but also how they are related to each other. We introduce social network analysis broadly used in the social capital theory, and extend the dimension of analysis for the evaluation of patent value. This study employs U.S. pharmaceutical patent data and investigates whether the network characteristic of backward citations have significant effect on the future patent value. The empirical results suggest that the network features of backward citations measured by constraint, cohesion, and efficiency have statistically significant implication on the value of invention in both level and depreciation rate. The study also provides empirical evidence that the exploration strategy is more significantly and positively correlated with the future value of invention compared to the exploitation strategy of inventors. 相似文献
392.
The present and future state of blended learning in workplace learning settings in the United States
This article reports a survey about blended learning in workplace learning settings. The survey found that blended learning gained popularity in many organizations but also that several barriers exist in implementing it. This survey also includes predictions on instructional strategies, emerging technologies, and evaluation techniques for blended learning. 相似文献
393.
The aim of the four present experiments was to explore how different schedules of reinforcement influence schedule-induced
behavior, their impact on evaluative ratings given to conditioned stimuli associated with each schedule through evaluative
conditioning, and the transfer of these evaluations through derived stimulus networks. Experiment 1 compared two contrasting
response reinforcement rules (variable ratio [VR], variable interval [VI]). Experiment 2 varied the response to reinforcement
rule between two schedules but equated the outcome to response rate (differential reinforcement of high rate [DRH] vs. VR).
Experiment 3 compared molar and molecular aspects of contingencies of reinforcement (tandem VIVR vs. tandem VRVI). Finally,
Experiment 4 employed schedules that induced low rates of responding to determine whether, under these circumstances, responses
were more sensitive to the molecular aspects of a schedule (differential reinforcement of low rate [DRL] vs. VI). The findings
suggest that the transfer of evaluative functions is determined mainly by differences in response rate between the schedules
and the molar aspects of the schedules. However, when neither schedule was based on a strong response reinforcement rule,
the transfer of evaluative judgments came under the control of the molecular aspects of the schedule. 相似文献
394.
Reed P 《Learning & behavior》2006,34(4):379-386
Three experiments were performed to examine the effect of response force on rats’ performance on various schedules of reinforcement.
Response force was manipulated by changing the weight of the lever in the operant chamber—a heavy lever for high response
force and a light lever for low response force. Using a within-subjects design, Experiment 1 replicated previous findings
that rats respond more quickly on variable ratio (VR) than on equivalent variable-interval-plus-linear-feedback (VI+) schedules.
Experiment 2 replicated this finding but also showed that the use of a smaller response force abolished the response rate
difference between the VR and VI+ schedules. Experiment 3 used a between-subjects design and showed a response rate difference
between the VR and VI+ schedules with a high response force but no response rate difference with a low response force. This
suggests that under conditions of low force, when the rats’ responding can continue at prolonged high rates, these subjects
show little difference in their response rates between VR and VI+ schedules. These data are similar to those found for human
subjects. 相似文献
395.
Recently, a polynomials-based integral inequality was proposed by extending the Moon’s inequality into a generic formulation. By imposing certain structures on the slack matrices of this integral inequality, this paper proposes an orthogonal-polynomials-based integral inequality which has lower computational burden than the polynomials-based integral inequality while maintaining the same conservatism. Further, this paper provides notes on relations among recent general integral inequalities constructed with arbitrary degree polynomials. In these notes, it is shown that the proposed integral inequality is superior to the Bessel–Legendre (B–L) inequality and the polynomials-based integral inequality in terms of the conservatism and computational burden, respectively. Moreover, the effectiveness of the proposed method is demonstrated by an illustrative example of stability analysis for systems with additive time-varying delays. 相似文献
396.
Wearable devices introduce many new capabilities to the delivery of healthcare. But wearables also pose grave privacy risks. Furthermore, information overload gets in the way of informed consent by the patient. To better protect American patients in an increasingly digital world, the U.S. Congress passed the Health Insurance Portability and Accountability Act of 1996 (HIPAA). This article examines the adequacy of HIPAA vis-à-vis issues raised by wearable technologies in the Internet of Things environment and identifies policy gaps and factors that drive health data exposure. It presents a 2 × 2 Partnership-Identity Exposure Matrix, illustrates implications in four different contexts, and provides recommendations for improving privacy protection. 相似文献
397.
Phil Reed 《Learning & behavior》2018,46(1):60-66
Hungry rats were trained in a two-lever conditioning chamber to earn food reinforcement according to either a win–shift/lose–stay or a win–stay/lose–shift contingency. Performance on the two contingencies was similar when there was little delay between the initial, information part of the trial (i.e., win or lose) and the choice portion of the trial (i.e., stay or shift with respect to the lever presented in the information stage). However, when a delay between the information and choice portions of the trial was introduced, subjects experiencing the win–shift/lose–stay contingency performed worse than subjects experiencing the alternative contingency. In particular, the lose–stay rule was differentially negatively impacted relative to the other rules. This result is difficult for ecological or response interference accounts to explain. 相似文献
398.