全文获取类型
收费全文 | 2646篇 |
免费 | 108篇 |
国内免费 | 66篇 |
专业分类
电工技术 | 47篇 |
综合类 | 301篇 |
化学工业 | 262篇 |
金属工艺 | 31篇 |
机械仪表 | 237篇 |
建筑科学 | 141篇 |
矿业工程 | 11篇 |
能源动力 | 17篇 |
轻工业 | 148篇 |
水利工程 | 6篇 |
石油天然气 | 15篇 |
武器工业 | 7篇 |
无线电 | 81篇 |
一般工业技术 | 199篇 |
冶金工业 | 807篇 |
原子能技术 | 3篇 |
自动化技术 | 507篇 |
出版年
2024年 | 6篇 |
2023年 | 18篇 |
2022年 | 120篇 |
2021年 | 90篇 |
2020年 | 43篇 |
2019年 | 38篇 |
2018年 | 29篇 |
2017年 | 37篇 |
2016年 | 38篇 |
2015年 | 45篇 |
2014年 | 82篇 |
2013年 | 133篇 |
2012年 | 102篇 |
2011年 | 174篇 |
2010年 | 146篇 |
2009年 | 206篇 |
2008年 | 188篇 |
2007年 | 196篇 |
2006年 | 173篇 |
2005年 | 192篇 |
2004年 | 132篇 |
2003年 | 119篇 |
2002年 | 96篇 |
2001年 | 72篇 |
2000年 | 41篇 |
1999年 | 23篇 |
1998年 | 18篇 |
1997年 | 34篇 |
1996年 | 19篇 |
1995年 | 18篇 |
1994年 | 22篇 |
1993年 | 21篇 |
1992年 | 12篇 |
1991年 | 8篇 |
1990年 | 12篇 |
1989年 | 20篇 |
1988年 | 13篇 |
1987年 | 15篇 |
1986年 | 10篇 |
1985年 | 9篇 |
1984年 | 4篇 |
1982年 | 3篇 |
1979年 | 4篇 |
1978年 | 2篇 |
1967年 | 3篇 |
1966年 | 4篇 |
1964年 | 3篇 |
1963年 | 5篇 |
1961年 | 2篇 |
1955年 | 2篇 |
排序方式: 共有2820条查询结果,搜索用时 15 毫秒
1.
Ahmadreza Momeni Amir G. Aghdam 《International Journal of Adaptive Control and Signal Processing》2007,21(10):885-910
Most of the existing switching control techniques are developed specifically for finite-dimensional linear time-invariant (LTI) systems. In many practical applications, however, it is essential to take time delay into consideration in the modelling as the control system can be highly sensitive to delay. In this paper, a multi-model switching control algorithm is proposed for retarded time-delay systems. It is assumed that the plant is represented by a family of known multi-input multi-output, observable, LTI models with multiple delays in the states, and that corresponding to each model in the known family, there exists a high-performance finite-dimensional LTI controller. In addition, it is supposed that a bound on the magnitude of the external inputs and disturbances is available. It is then shown that the proposed switching controller can stabilize the uncertain system, and that under some mild conditions, output tracking can be achieved in the given problem setting. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
2.
分析了当前家装存在的破坏结构,一味追求奢华,施工质量差等种种误区,提出了搞好家庭装修的关键环节,对促进家装行业健康发展有积极的意义。 相似文献
3.
During the day, there are considerable variations in the climatic factors prevailing in these regions. This is especially so during the 24-hour daily cycle of the long, hot and dry summer (mid-May to midOctober). Such climatic conditions have had a considerable impact on the daily living pattern of family life in the same season, particularly in the urban areas. During the same 24-hour cycle, they have compelled the inhabitants to shift their living activities both vertically in section and horizontally in plan; they do this in pursuit of more acceptable, if not, desirable internal thermal environmental ambience. 相似文献
4.
Reviews the book, Psychologie de la famille by Monique V. G. Morval (1985). Morval presents a book with two views: the first looks at the axis of the family in light of systemic approaches and the second centers on the cycle of family life. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
The famous Antosik-Mikusinski convergent theorem on the Abel topological groups has very extensive applications in measure theory, summation theory and other analysis fields. In this paper, we establish the theorem on a class of effect algebras equipped with the ideal topology. This paper shows also that the ideal topology of effect algebras is a useful topology in studying the quantum logic the- ory. 相似文献
6.
This study aimed to better understand the impact of business trips on the traveler, the family, and the organization; to learn about maximizing the positive aspects of business travel; and to suggest measures to prevent and manage travel stress. Thirty-five business travelers (American, Israeli, and Swedish) were interviewed about the costs and benefits of their traveling, with a focus on gaining insight into coping strategies. Content analysis of the interviews showed that trips consist of 4 phases--(a) pretrip, (b) journey, (c) stay, and (d) posttrip--and that each phase is characterized by different coping strategies. Business travelers reported using proactive individual and organizational coping strategies in the pretrip phase and a combination of proactive and reactive coping strategies in the other phases. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
This article presents the abandonment-symbiosis hypothesis. This hypothesis pertains to the dynamics of suicide in youngsters who experience difficulties in separation from their symbiotic families. It is suggested that such youngsters have experienced various types of rejection and abandonment in early childhood and have developed insecure attachment styles and insufficient ego functions in order to cope with difficulties. It is also suggested that these youngsters have become scapegoats by their dysfunctional families and that they are held in a symbiotic grip in order to continue to bear the negative projections of their families. As such, they are prevented from developing a proper sense of individuation and autonomy. The sequence that begins with abandonment and continues with symbiosis is a reversal of normal development is critical for the emergence of suicidal behavior. The various aspects of the abandonment-symbiosis hypothesis are demonstrated by case studies and empirical data. A combination of individual and family treatment is recommended as the best approach for the treatment of such youngsters. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
N. S. Nikitchenko 《Cybernetics and Systems Analysis》2003,39(1):97-112
Predicates that preserve their values on a larger (extended) body of data are called equitone. An algebra of such predicates is constructed, a system of its generators is specified, and a complete system of transformations of identities is defined. The results obtained are used for construction and investigation of complete classes of compositions of various types and levels of abstractions that are used in logics of partial predicates. 相似文献
9.
Robbins Michael S.; Turner Charles W.; Alexander James F.; Perez Gonzalo A. 《Canadian Metallurgical Quarterly》2003,17(4):534
This study examined the relationship between alliance and retention in family therapy. Alliance was examined at the individual (parent and adolescent) and family levels (within-family differences). Participants were 34 families who received functional family therapy for the treatment of adolescent (aged 12-18 years) behavior problems. Families were classified as treatment dropouts (n=14) or completers (n=20). Videotapes of the first sessions were rated to identify parent and adolescent alliances with the therapist. Results demonstrated that individual parent and adolescent alliances did not predict retention. However, as hypothesized, dropout cases had significantly higher unbalanced alliances (parent minus adolescent) than did completer cases. These findings highlight the importance of alliances in functional family therapy and suggest that how the alliance operates in conjoint family therapy may be a function of systemic rather than of individual processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.