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   588篇
  免费   5篇
教育   431篇
科学研究   50篇
各国文化   3篇
体育   56篇
文化理论   6篇
信息传播   47篇
  2023年   1篇
  2022年   11篇
  2021年   21篇
  2020年   21篇
  2019年   25篇
  2018年   34篇
  2017年   37篇
  2016年   26篇
  2015年   20篇
  2014年   31篇
  2013年   119篇
  2012年   25篇
  2011年   24篇
  2010年   19篇
  2009年   15篇
  2008年   14篇
  2007年   12篇
  2006年   7篇
  2005年   14篇
  2004年   11篇
  2003年   9篇
  2002年   7篇
  2001年   6篇
  2000年   3篇
  1999年   2篇
  1998年   4篇
  1997年   2篇
  1996年   11篇
  1995年   5篇
  1994年   4篇
  1993年   2篇
  1992年   4篇
  1991年   5篇
  1990年   5篇
  1989年   3篇
  1988年   2篇
  1987年   1篇
  1986年   3篇
  1985年   3篇
  1984年   4篇
  1983年   3篇
  1982年   6篇
  1981年   2篇
  1980年   2篇
  1979年   3篇
  1978年   1篇
  1976年   1篇
  1975年   1篇
  1967年   1篇
  1966年   1篇
排序方式: 共有593条查询结果,搜索用时 15 毫秒
41.
Distributed systems consist of interconnected, lower-dimensional subsystems. For such systems, distributed analysis and design present several advantages, such as modularity, easier analysis and design, and reduced computational complexity. A special case of distributed systems is when the subsystems are connected in a string. Applications include distributed process control, traffic and communication networks, irrigation systems, hydropower valleys, etc. By exploiting such a structure, in this paper, we propose conditions for the distributed stability analysis of Takagi–Sugeno fuzzy systems connected in a string. These conditions are also extended to observer and controller design and illustrated on numerical examples.  相似文献   
42.
This study compared the ways that graduate and undergraduate counseling and psychology students from Portugal and the United States evaluated the feelings of Love, Anger and Guilt. Utilizing a semantic differential, a multivariate analysis of variance was employed in which the independent variables were Country and Gender and the dependent variables were the evaluative and potency scales of Love, Anger and Guilt. There was no significant main effect for gender and there was no significant interaction effect for gender by country. There was a significant main effect for country. It was found that students from the United States evaluated Anger more positively than the Portuguese students and that the Portuguese students evaluated Guilt more positively than the United States students. These findings have implications that are relevant to the counseling process.  相似文献   
43.
Students’ writing problems are a global educational concern and is in need of particular attention. This study aims to examine the impact of providing extra writing opportunities (i.e., writing journals) on the quality of writing compositions. A longitudinal cluster-randomized controlled design using a multilevel modeling analysis with 182 fourth grade students was conducted. We examined whether students’ writing quality differed when writing journals on a weekly basis for 12 weeks, compared with a control group. Three covariates were analyzed, namely: (i) the students’ attitudes towards writing; (ii) their self-efficacy in writing; (iii) and their use of self-regulation (SRL) strategies while writing. Findings have shown that students who wrote week-journals significantly improved the writing quality of their compositions and reported a higher use of SRL strategies in writing. Nevertheless, self-efficacy and attitude towards writing were found to not be related to the quality of the compositions. Moreover, data indicated that the writing quality of compositions improved along with the writing quality of the week-journals. Findings suggest the use of week-journals in class to promote writing.  相似文献   
44.
Most youth in juvenile delinquent systems end up incarcerated due in part to poor decision-making skills. This study describes a theoretical framework undergirding the relationships across delinquency, learning climate, decision-making, and computational logic. This framework will inform a team of educators, criminologists, and psychologists, and their peers in computer science and mathematics, instructional software design, and content experts as they build and test an innovative instructional model for youth in secure care settings. The goal of the system is to improve human decision-making skills, while preparing youth for further education potentially leading to careers in STEM fields.  相似文献   
45.
Employers’ recruitment behaviour in entry labour markets is central for young people’s transitions from school to work. Whereas previous research has focused on the effects of specific applicant characteristics, I concentrate on how organisational characteristics, namely organisation size and private or public sector affiliation, relate to selection decisions in the dual apprenticeship system in Germany which is a major entry labour market. Following organisational and institutional theory, I expect early selection stages to be more open at larger and public organisations in contrast to smaller private organisations. I also investigate how different organisations respond to school grades as applicants’ signals of skills. I use field experiment data combining organisational-level and applicant-level data to analyse how actual employer responses to written applications by fictitious young people vary with organisation type. The results indicate that, net of applicant characteristics and occupation-specific practices, applications are more likely to receive an invitation to a follow-up selection stage if submitted to larger organisations, and especially larger public organisations, rather than to smaller private organisations. This finding extends to applicants with poorer school grades. Public sector affiliation, however, did not seem to matter much within the group of smaller organisations.  相似文献   
46.

Objectives

Published protocols for forensic interviewing for child sexual abuse do not include specific questions about what prompted children to tell about sexual abuse or what made them wait to tell. We, therefore, aimed to: (1) add direct inquiry about the process of a child's disclosure to a forensic interview protocol; (2) determine if children will, in fact, discuss the process that led them to tell about sexual abuse; and (3) describe the factors that children identify as either having led them to tell about sexual abuse or caused them to delay a disclosure.

Methods

Forensic interviewers were asked to incorporate questions about telling into an existing forensic interview protocol. Over a 1-year period, 191 consecutive forensic interviews of child sexual abuse victims aged 3-18 years old in which children spoke about the reasons they told about abuse or waited to tell about abuse were reviewed. Interview content related to the children's reasons for telling or for waiting to tell about abuse was extracted and analyzed using a qualitative methodology in order to capture themes directly from the children's words.

Results

Forensic interviewers asked children about how they came to tell about sexual abuse and if children waited to tell about abuse, and the children gave specific answers to these questions. The reasons children identified for why they chose to tell were classified into three domains: (1) disclosure as a result of internal stimuli (e.g., the child had nightmares), (2) disclosure facilitated by outside influences (e.g., the child was questioned), and (3) disclosure due to direct evidence of abuse (e.g., the child's abuse was witnessed). The barriers to disclosure identified by the children were categorized into five groups: (1) threats made by the perpetrator (e.g., the child was told (s)he would get in trouble if (s)he told), (2) fears (e.g., the child was afraid something bad would happen if (s)he told), (3) lack of opportunity (e.g., the child felt the opportunity to disclose never presented), (4) lack of understanding (e.g., the child failed to recognize abusive behavior as unacceptable), and (5) relationship with the perpetrator (e.g., the child thought the perpetrator was a friend).

Conclusions

Specific reasons that individual children identify for why they told and why they waited to tell about sexual abuse can be obtained by direct inquiry during forensic interviews for suspected child sexual abuse.

Practice implications

When asked, children identified the first person they told and offered varied and specific reasons for why they told and why they waited to tell about sexual abuse. Understanding why children disclose their abuse and why they wait to disclose will assist both professionals and families. Investigators and those who care for sexually abused children will gain insight into the specific barrier that the sexually abused child overcame to disclose. Prosecutors will be able to use this information to explain to juries why the child may have delayed his or her disclosure. Parents who struggle to understand why their child disclosed to someone else or waited to disclose will have a better understanding of their child's decisions.  相似文献   
47.
This paper addresses the role that scientific status plays in initial public offerings of technology focused firms. The paper builds on the literature of the sociology of science as well as the work of Spence (1974) and Podolny (1993) and argues that the presence of a Nobel laureate affiliated with a firm making an IPO provides a signal of firm quality to potential investors. Moreover, and building on the work of Podolny and Scott Morton (1999) and Stuart et al. (1999) we hypothesize that the importance of status diminishes as other measures of firm quality become available. We test our hypothesis for two periods of initial public offerings in biotechnology. We document that there is a clear difference in “maturity” of the firms across the two windows on a number of metrics. Consistent with our hypothesis that Nobel laureates play an important role as a non-financial signal of firm quality, we find that first-window firms with a Nobel laureate affiliate realize greater IPO proceeds in the amount of $24 million. In the second window the amount of money raised is not significantly different between Nobel and non-Nobel firms. This finding is consistent with the signaling literature that argues that the importance of a signal is inversely related to the availability of cogent information on firm quality. Consistent with this view, we also find a change between the two windows in the importance of other non-financial metrics used to convey value. Our research is one of the first to examine the dynamic nature of signals. Because we are unable to distinguish the extent to which the reduction in uncertainty at the firm level is correlated with the reduction of uncertainty at the industry level, the question remains as to the extent to which the diminished importance of signals in our second period is due to a change in market uncertainty versus a change in firm uncertainty.  相似文献   
48.
Many services can be self-provided. An individual user or a user firm can, for example, choose to do its own accounting - choose to self-provide that service - instead of hiring an accounting firm to provide it. Since users can ‘serve themselves’ in many cases, it is reasonable to suspect that they can also innovate with respect to the services they self-provide - possibly without the assistance of service providers.In this paper, we conduct the first quantitative exploration of the importance of services innovation by users, focusing on the field of commercial and retail banking services. We find that 55% of today's computerized commercial banking services were first developed and implemented by non-bank firms for their own use, and 44% of today's computerized retail banking services were first developed and implemented by individual service users rather than by commercial financial service providers. Manual precursors to these services - manual procedures that carried out functions similar to computerized services in our sample - were almost always developed by users as self-services.Our empirical findings differ significantly from prevalent producer-centered views of service development. We speculate that the patterns we have observed in banking with respect to the major role of users in service development will prove to be quite general. If so, this will be an important matter: on the order of 75% of GDP in advanced economies today is derived from services. We discuss the implications of our findings for research and practice in service development.  相似文献   
49.

Objective:

The objective of this study was to validate an assessment instrument for MEDLINE search strategies at an academic medical center.

Method:

Two approaches were used to investigate if the search assessment tool could capture performance differences in search strategy construction. First, data from an evaluation of MEDLINE searches from a pediatric resident''s longitudinal assessment were investigated. Second, a cross-section of search strategies from residents in one incoming class was compared with strategies of residents graduating a year later. MEDLINE search strategies formulated by faculty who had been identified as having search expertise were used as a gold standard comparison. Participants were presented with a clinical scenario and asked to identify the search question and conduct a MEDLINE search. Two librarians rated the blinded search strategies.

Results:

Search strategy scores were significantly higher for residents who received training than the comparison group with no training. There was no significant difference in search strategy scores between senior residents who received training and faculty experts.

Conclusion:

The results provide evidence for the validity of the instrument to evaluate MEDLINE search strategies. This assessment tool can measure improvements in information-seeking skills and provide data to fulfill Accreditation Council for Graduate Medical Education competencies.

Highlights

  • The University of Michigan MEDLINE Search Assessment tool can be used to assess search skills in residency education.
  • Five elements were identified as critical elements in the development of an effective MEDLINE search strategy: inclusion of all search concepts, appropriate use of Medical Subject Headings, appropriate use of search limits, successful combination of all concepts, and search efficiency.

Implications

  • This validated assessment tool can serve as an effective means to measure improvements in residents'' information-seeking skills and provide data to fulfill Accreditation Council for Graduate Medical Education competencies.
  相似文献   
50.
In this paper, four teachers shared their experiences using the following free Web 2.0 tools with their students: Jing, Wix, Google Sites, and Blogger. The teachers found that students reacted positively to lessons in which these tools were used, and also noted improvements they could make when using them in the future.  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