全文获取类型
收费全文 | 1474篇 |
免费 | 14篇 |
学科分类
工业技术 | 1488篇 |
出版年
2022年 | 9篇 |
2021年 | 9篇 |
2020年 | 9篇 |
2019年 | 7篇 |
2017年 | 8篇 |
2016年 | 5篇 |
2015年 | 12篇 |
2014年 | 15篇 |
2013年 | 32篇 |
2012年 | 26篇 |
2011年 | 39篇 |
2010年 | 29篇 |
2009年 | 42篇 |
2008年 | 30篇 |
2007年 | 30篇 |
2006年 | 38篇 |
2005年 | 39篇 |
2004年 | 34篇 |
2003年 | 29篇 |
2002年 | 23篇 |
2001年 | 19篇 |
2000年 | 25篇 |
1999年 | 42篇 |
1998年 | 188篇 |
1997年 | 103篇 |
1996年 | 78篇 |
1995年 | 59篇 |
1994年 | 37篇 |
1993年 | 45篇 |
1992年 | 31篇 |
1991年 | 24篇 |
1990年 | 22篇 |
1989年 | 28篇 |
1988年 | 19篇 |
1987年 | 17篇 |
1986年 | 18篇 |
1985年 | 24篇 |
1984年 | 18篇 |
1983年 | 16篇 |
1982年 | 16篇 |
1981年 | 24篇 |
1980年 | 17篇 |
1979年 | 11篇 |
1978年 | 6篇 |
1977年 | 21篇 |
1976年 | 38篇 |
1975年 | 9篇 |
1974年 | 6篇 |
1973年 | 8篇 |
1972年 | 9篇 |
排序方式: 共有1488条查询结果,搜索用时 0 毫秒
101.
The authors examine the performance, cost, and schedule tradeoffs made for the NS 32532, a 32-bit general-purpose microprocessor. Among its features are a 30-MHz clock frequency, three on-chip caches, a four-stage pipeline, and dedicated mechanisms for multiprocessing support. The authors describe the design constraints set by the VLSI processing and packaging technologies. They address the issue of market requirements by examining the software and hardware considerations for the microprocessor's target applications. After describing the functional partitioning choices, including the means for supporting a memory hierarchy and floating-point operations, they present the NS32532's microarchitecture. They then examine the microprocessor's system interface, the memory reference transactions, and the instruction-flow and data-flow monitoring mechanisms. Finally, the authors present an overview of the methodology adopted to accomplish the design within a strict schedule while achieving full functionality and meeting cost and performance goals 相似文献
102.
103.
104.
Diarrhea is still a major cause of morbidity and mortality among children in developing countries. The Bedouin population of southern Israel is in transition from a nomadic to a settled life-style. We examined maternal knowledge and reported behavior when their children had diarrhea. Mothers defined diarrhea as the passing of 4-5 stools per day. The most frequent signs of the illness were an increased number of watery stools with changes in either color or form. The most frequent symptom that prompted mothers to seek medical aid was blood in the stool. All mothers reported increasing fluid intake in their children during diarrhea, and most reported giving herbal tea. About half of the women avoided milk products and used special foods for the treatment of diarrhea. A quarter of the women reported stopping or decreasing the frequency of breast feeding during diarrhea. Reported cessation of breast feeding during diarrhea was associated with changing to special foods, and failure to note the onset of diarrhea or to recognize signs of dehydration. The withdrawal of breast feeding during episodes of illness and diarrhea is related to lack of knowledge regarding diarrhea. These data indicate that even in this population, with free access to preventive and curative medical care, there should be greater efforts to educate mothers to detect diarrheal disease and to maintain breast feeding during the diarrhea. 相似文献
105.
106.
The authors investigated whether contextual failures in schizophrenia are due to deficits in the detection of context or the inhibition of contextually irrelevant information. Eighteen schizophrenia patients and 24 nonpsychiatric controls were tested via a cross-modal semantic priming task. Participants heard sentences containing homonyms and made lexical decisions about visual targets related to the homonyms' dominant or subordinate meanings. When sentences moderately biased subordinate meanings (e.g., the animal enclosure meaning of pen), schizophrenia patients showed priming of dominant targets (e.g., paper) and subordinate targets (e.g., pig). In contrast, controls showed priming only of subordininate targets. When contexts strongly biased subordinate meanings, both groups showed priming only of subordinate targets. The results suggest that inhibitory deficits rather than context detection deficits underlie contextual failures in schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
Levy Bruce P. Campbell Steven L. Rose Timothy L. 《IEEE transactions on bio-medical engineering》1986,(11):1046-1049
The geometric area of the tip of an intracortical stimulation electrode can be defined by combining photoresist masking with oxygen plasma etching of Parylene.1 The method was tested with both capacitor and iridium oxide electrodes and caused no significant degradation of the electrical properties of the electrode. 相似文献
108.
R. Levy 《Design Studies》1985,6(2):66-72
It is argued, through a historical review of human inquiry systems, that contemporary science is not in epistemological chaos as suggested by some authors. It should not, therefore, be overlooked as a source of constitutive knowledge relevant to the activity of design. It is suggested that the present state of scientific epistemology embodies the principles not only of science but also those of technology, industry and society, and that design should be viewed as an activity in conjunction with this paradigmatic organization and not solely as a technological activity. 相似文献
109.
Amar A.P. Levy M.L. Liu C.Y. Apuzzo M.L.J. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2008,96(7):1142-1151
Vagus nerve stimulation (VNS) is a safe and reliable treatment adjunct for patients with medically intractable epilepsy. It is both a preventive and an abortive form of therapy, potentially effective against both partial and generalized seizures in adults and children. VNS also has a number of serendipitous effects on mood, memory, and attention and has been approved for the treatment of refractory depression. Because of its pleiotropic effects, it holds promise for several other diseases as well. Its principal limitations are its unknown mechanism of action, the low likelihood of complete cure, and the inability to predict which patients will derive substantial benefit. This paper reviews the theoretical rationale, practical background, and clinical applications of VNS therapy. 相似文献
110.