全文获取类型
收费全文 | 1122篇 |
免费 | 20篇 |
专业分类
教育 | 765篇 |
科学研究 | 101篇 |
各国文化 | 12篇 |
体育 | 167篇 |
文化理论 | 19篇 |
信息传播 | 78篇 |
出版年
2023年 | 7篇 |
2022年 | 14篇 |
2021年 | 25篇 |
2020年 | 53篇 |
2019年 | 81篇 |
2018年 | 100篇 |
2017年 | 98篇 |
2016年 | 63篇 |
2015年 | 51篇 |
2014年 | 48篇 |
2013年 | 251篇 |
2012年 | 42篇 |
2011年 | 42篇 |
2010年 | 20篇 |
2009年 | 26篇 |
2008年 | 21篇 |
2007年 | 22篇 |
2006年 | 13篇 |
2005年 | 14篇 |
2004年 | 11篇 |
2003年 | 16篇 |
2002年 | 8篇 |
2001年 | 16篇 |
2000年 | 8篇 |
1999年 | 7篇 |
1998年 | 6篇 |
1997年 | 8篇 |
1996年 | 2篇 |
1995年 | 12篇 |
1994年 | 3篇 |
1993年 | 4篇 |
1992年 | 7篇 |
1990年 | 4篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1978年 | 3篇 |
1976年 | 2篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1955年 | 1篇 |
1948年 | 1篇 |
1830年 | 1篇 |
排序方式: 共有1142条查询结果,搜索用时 31 毫秒
61.
Gunnlaugsson G Kristjánsson AL Einarsdóttir J Sigfúsdóttir ID 《Child abuse & neglect》2011,35(5):372-381
Objectives
During intrafamilial conflicts children are often innocent bystanders, caught in the crossfire. In such situations, they are at increased risk to become directly involved in abusive verbal behavior of the perpetrator, and exposed to being shouted or yelled at, threatened, rejected and even physically abused. The present study has two main objectives: (1) ascertain a national base rate of intrafamilial conflicts and physical violence at home among Icelandic adolescents; and (2) to investigate the association of witnessing and/or having been a part of intrafamilial conflict or physical violence at home with variables that relate to mental health and well-being.Methods
The participants were 3,515 students, 14- and 15-year-old, in the national compulsory school system in Iceland. As a part of the 2003 ESPAD survey, each pupil was asked about experiences of severe verbal arguments and physical violence at home as well as their background, behaviors, and mental health assessed with the use of tested measurement scales such as the Symptom Distress Checklist 90 (SCL-90) and the Rosenberg Self-Esteem Scale.Results
About 22% of the participants stated that they had witnessed a severe verbal argument between parents and 34% stated that they had been involved in a severe verbal argument with parents. This rate was slightly higher for girls compared to boys. All together 7% of adolescents had witnessed physical violence at home where an adult was involved and 6% of the participants stated that they had experiences of being involved in physical violence at home where an adult was involved. Witnessing or being involved in severe verbal arguments at home and/or witnessing or being involved in physical violence with an adult was significantly associated with greater levels of depression, anger, and anxiety, and negatively related with self-esteem (p < 0.01).Conclusions
Many adolescents in Iceland witness severe parental verbal arguments or physical violence between adults in their homes and some are directly involved in such acts. It affects their long-term emotional and behavioral development and well-being.Practice implications
Preventive measures have to be implemented at an early age and should include, but not be limited to, information on disciplining and upbringing of children and the negative impact of intrafamilial conflicts on the long-term health of their children. Due attention should be given to the health and well-being of children where such violence is known to occur. 相似文献62.
63.
Eduardo N. Borges Moisés G. de Carvalho Renata Galante Marcos André Gonçalves Alberto H.F. Laender 《Information processing & management》2011
Digital libraries of scientific articles contain collections of digital objects that are usually described by bibliographic metadata records. These records can be acquired from different sources and be represented using several metadata standards. These metadata standards may be heterogeneous in both, content and structure. All of this implies that many records may be duplicated in the repository, thus affecting the quality of services, such as searching and browsing. In this article we present an approach that identifies duplicated bibliographic metadata records in an efficient and effective way. We propose similarity functions especially designed for the digital library domain and experimentally evaluate them. Our results show that the proposed functions improve the quality of metadata deduplication up to 188% compared to four different baselines. We also show that our approach achieves statistical equivalent results when compared to a state-of-the-art method for replica identification based on genetic programming, without the burden and cost of any training process. 相似文献
64.
65.
Our work concerns the design of robust information retrieval environments that can successfully handle queries containing misspelled words. Our aim is to perform a comparative analysis of the efficacy of two possible strategies that can be adopted. 相似文献
66.
Mapping the importance of the real world: The validity of connectivity analysis of patent citations networks 总被引:1,自引:0,他引:1
Recent empirical findings have questioned the use of patent citations as a measure. This points to the need of validation of patent citations methodologies, which we address by testing a recent methodology for studying technological evolution, namely connectivity analysis of citation networks. We find connectivity analysis to be a valid tool to identify the reliable knowledge which opens the way to further technological evolution of a surgical prosthesis, the artificial spinal disc. We also illustrate how connectivity analysis represents how this reliable knowledge differs depending on the stage of technological evolution. The corroborated validity of connectivity analysis of patent citations may trigger a renaissance in the use of this kind of patent data. 相似文献
67.
Dustin Hillard Eren Manavoglu Hema Raghavan Chris Leggetter Erick Cantú-Paz Rukmini Iyer 《Information Retrieval》2011,14(3):315-336
The critical task of predicting clicks on search advertisements is typically addressed by learning from historical click data.
When enough history is observed for a given query-ad pair, future clicks can be accurately modeled. However, based on the
empirical distribution of queries, sufficient historical information is unavailable for many query-ad pairs. The sparsity
of data for new and rare queries makes it difficult to accurately estimate clicks for a significant portion of typical search
engine traffic. In this paper we provide analysis to motivate modeling approaches that can reduce the sparsity of the large
space of user search queries. We then propose methods to improve click and relevance models for sponsored search by mining
click behavior for partial user queries. We aggregate click history for individual query words, as well as for phrases extracted
with a CRF model. The new models show significant improvement in clicks and revenue compared to state-of-the-art baselines
trained on several months of query logs. Results are reported on live traffic of a commercial search engine, in addition to
results from offline evaluation. 相似文献
68.
69.
This article presents the results of two research projects on the emotions of men engaged in achievement outdoor sports. The conditions were analyzed under which emotions carry out positive functions. The question strikes us as a fundamental one, because it is of crucial importance when it comes to increasing sportspeople's success. The theoretical framework applied was that of microfunctionalism. The method, of a qualitative nature, was based on in-depth interviews, each lasting between 1.5 and 2 hr with a total of 14 sportspersons. The results show that in order for emotions to fulfill positive functions, three conditions must be met: (a) existence of passion, which, with its dialectical character of pleasure and suffering underlies all the other emotions and acts as a motor that pushes the sportsperson forward, despite all the contretemps he might meet on the way; (b) intense emotion work, which may be conducted only if accompanied by knowledge and experience of the natural environment acquired over the years; and (c) conciliation between emotion work and the feeling rules characteristic of each sport subculture. For those individuals who pursue achievement in outdoor sports, these results will provide more concrete indications regarding how to carry out the emotional preparation required for these sports. 相似文献
70.
Gallardo-Montes Carmen del Pilar Caurcel Cara María Jesús Rodríguez Fuentes Antonio 《Education and Information Technologies》2022,27(3):4087-4115
Education and Information Technologies - Mobile apps represent a resource with great potential for encouraging the development of many skills, given the high number of apps available and the quick... 相似文献