全文获取类型
收费全文 | 779篇 |
免费 | 71篇 |
国内免费 | 62篇 |
专业分类
电工技术 | 21篇 |
综合类 | 103篇 |
化学工业 | 7篇 |
金属工艺 | 2篇 |
机械仪表 | 17篇 |
建筑科学 | 22篇 |
矿业工程 | 9篇 |
能源动力 | 2篇 |
轻工业 | 7篇 |
水利工程 | 4篇 |
石油天然气 | 2篇 |
无线电 | 109篇 |
一般工业技术 | 14篇 |
冶金工业 | 272篇 |
原子能技术 | 2篇 |
自动化技术 | 319篇 |
出版年
2023年 | 6篇 |
2022年 | 6篇 |
2021年 | 6篇 |
2020年 | 10篇 |
2019年 | 14篇 |
2018年 | 8篇 |
2017年 | 14篇 |
2016年 | 22篇 |
2015年 | 18篇 |
2014年 | 20篇 |
2013年 | 25篇 |
2012年 | 51篇 |
2011年 | 70篇 |
2010年 | 78篇 |
2009年 | 58篇 |
2008年 | 91篇 |
2007年 | 82篇 |
2006年 | 61篇 |
2005年 | 64篇 |
2004年 | 58篇 |
2003年 | 37篇 |
2002年 | 37篇 |
2001年 | 20篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1997年 | 4篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 5篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1970年 | 1篇 |
1968年 | 1篇 |
1965年 | 4篇 |
1964年 | 2篇 |
1963年 | 3篇 |
1962年 | 3篇 |
1961年 | 1篇 |
1959年 | 1篇 |
1957年 | 2篇 |
1956年 | 1篇 |
1955年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有912条查询结果,搜索用时 0 毫秒
21.
赵磊 《河南机电高等专科学校学报》2012,20(4):68-71
我国行政奖励是行政行为的重要表现形式之一。然而,对行政奖励的行政法研究在我国并没有得到应有的重视。从阐述行政奖励的基本内涵出发,着重剖析行政奖励的基本原则:依法奖励,实事求是原则;精神奖励和物质奖励相结合原则;一事不再奖励原则;信赖保护与效益至上原则。针对我国行政奖励实践中存在的问题,赋予行政奖励新的时代内涵,并提出完善我国行政奖励制度的若干建议。 相似文献
22.
23.
Observational methods were used to examine aggressive children's peer relations in 2 contexts: when being teased by a peer and when interacting with a best friend. Because aggressive children may have more difficulty than nonaggressive children in both peer contexts, the authors also examined whether relations between behaviors across contexts varied as a function of aggression. Results indicated that aggression was related to children's behavior when provoked. Children's behavior when provoked was associated with fewer positive and more negative interactions with their best friend, particularly for aggressive children. Results are discussed with respect to social norms in middle childhood and informing interventions for aggressive children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
Salmivalli Christina; Ojanen Tiina; Haanp?? Jemina; Peets K?tlin 《Canadian Metallurgical Quarterly》2005,41(2):363
This study examined the links among 5th and 6th graders' (279 girls and 310 boys) self- and peer perceptions, social goals, and social behavior. Social goals mediated the effects of self- and peer perceptions on 3 types of behavior: proactive aggression, prosocial behavior, and withdrawal. In addition to their main effects (self-perception predicting variance in agentic goals, peer perception being related to communal goals), self- and peer perception interacted in influencing social goals; for instance, the effects of a positive view of oneself were different in the contexts of a positive versus a negative perception of peers. It is suggested that in order to predict children's social behavior more accurately, researchers should investigate children's dual perceptions of themselves and of their peers--that is, their peer-relational schemas--instead of assessing self-perception and peer perception in isolation from each other. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
25.
The authors examined class size effects on teacher-pupil interactions, pupil engagement, and pupil-pupil interaction. They extended previous research by recognizing the hierarchical nature of observation data and the possible influence of other variables. The study used a time sampling method involving 257 children (aged 10-11 years) in 16 small (25 or under) and 26 large (31 and over) classes. In small classes, there were more individualized task-related contacts between teacher and pupils and a more active role for pupils. These results confirmed those from earlier research on children aged 4 and 5 years. Against expectation, class size did not affect pupil on-task behavior or peer interaction. There was a moderating role for school subject and a beneficial effect of teaching assistants. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
26.
Virtual peers as partners in storytelling and literacy learning 总被引:2,自引:0,他引:2
Abstract Literacy learning — learning how to read and write — begins long before children enter school. One of the key skills to reading and writing is the ability to represent thoughts symbolically and share them in language with an audience who may not necessarily share the same temporal and spatial context. Children learn and practice these important language skills everyday, telling stories with the peers and adults around them. In particular, storytelling in the context of peer collaboration provides a key environment for children to learn language skills important for literacy. In light of this, an embodied conversational agent, Sam , who tells stories collaboratively with children was designed. Sam looks like a peer for pre-school children, but tells stories in a developmentally advanced way, modelling narrative skills important for literacy. Results demonstrated that children who played with the virtual peer told stories that more closely resembled the virtual peer's linguistically advanced stories: using more quoted speech and temporal and spatial expressions. In addition, children listened to Sam's stories carefully, assisting her and suggesting improvements. The potential benefits of having technology play a social role in young children's literacy learning is discussed. 相似文献
27.
Combining interaction and context design to support collaborative argumentation using a tool for synchronous CMC 总被引:4,自引:1,他引:4
Simon Mcalister rew Ravenscroft† & Eileen Scanlon 《Journal of Computer Assisted Learning》2004,20(3):194-204
Abstract Empirical studies and theory suggest that educational dialogue can be used to support learners in the development of reasoning, critical thinking and argumentation. This paper presents an educational design for synchronous online peer discussion that guides student dialogue in ways that lead to improved argumentation and collaborative knowledge development. This design includes a mediating interface – or tool, linked to a broader set of online educational activities – a designed local context, where the latter aims to provide conditions that support argumentation. The approach is based on collaborative working and dialogue game approaches to discussion. Preliminary findings with UK Open University students showed the argumentation process was more coherent, varied, deeper and extended when using our interaction design compared with the use of a simple unstructured interface. 相似文献
28.
This 6-year longitudinal study examined girls' peer-nominated social preference and aggression in childhood as predictors of self- and parent-reported externalizing symptoms, substance use (i.e.. cigarette, alcohol, and marijuana use), and sexual risk behavior in adolescence. Participants were 148 girls from diverse ethnic backgrounds, who were initially assessed in Grades 4-6 and again in Grades 10-12. Results supported a moderator model, indicating that social preference changed the nature of the association between childhood aggression and adolescent outcomes. When accompanied by peer rejection, aggressive behavior was moderately stable over time and significantly associated with adolescent girls' substance use and sexual risk behavior. However, under conditions of peer acceptance, no significant association between childhood aggression and adolescent outcomes emerged. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
29.
This study investigated the ways in which exposure to interparental conflict may affect adolescent dating relationships in a sample of 391 adolescents ages 14 to 18 years. Boys exposed to greater parental discord were more likely to view aggression as justifiable in a romantic relationship, had more difficulty managing anger, and believed that aggressive behavior was more common in their peers' dating relationships. Each of these variables in turn linked witnessing interparental conflict to higher levels of verbal and physical aggression toward their own romantic partners. Interparental conflict was not related to girls' aggressive behavior. These data support the value of targeting cognitive and emotional processes in prevention programs designed to reduce dating violence and suggest that such programs will be strengthened by focusing on peer influences as well. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.
P2P即时通信模型要求所有对等节点都能进行双向通信,但网络安全技术方案的实施,使得整个P2P通信域有了内网和外网的区分,并且外网节点不能向内网主动发起连接,故P2P双向心通信受到限制。本文分析并设计了一种高效的通信机制-小服务器节点(Small Service Peer)避免由第三方的通信中继服务所导致的延时。提出了内网中继判定算法,以优化处于同一内网节点之间通信的性能。试验表明,采用本文提出小服务器对等节点的通信机制和内网中继判定算法,在不改变下层网络结构和配置的条件下,可以显著降低P2P应用系统对中继服务器的依赖,并提高即时通信系统实时性。 相似文献