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   210篇
  免费   4篇
电工技术   2篇
化学工业   37篇
建筑科学   3篇
轻工业   1篇
无线电   25篇
一般工业技术   31篇
冶金工业   19篇
自动化技术   96篇
  2023年   3篇
  2022年   3篇
  2021年   12篇
  2020年   2篇
  2019年   4篇
  2018年   3篇
  2017年   1篇
  2016年   4篇
  2015年   8篇
  2014年   2篇
  2013年   8篇
  2012年   14篇
  2011年   8篇
  2010年   9篇
  2009年   21篇
  2008年   13篇
  2007年   13篇
  2006年   7篇
  2005年   2篇
  2004年   9篇
  2003年   3篇
  2002年   7篇
  2001年   3篇
  2000年   5篇
  1999年   5篇
  1998年   3篇
  1997年   4篇
  1996年   4篇
  1995年   3篇
  1992年   1篇
  1991年   3篇
  1989年   1篇
  1988年   1篇
  1987年   2篇
  1986年   2篇
  1985年   2篇
  1979年   3篇
  1978年   2篇
  1977年   6篇
  1976年   2篇
  1975年   5篇
  1973年   1篇
排序方式: 共有214条查询结果,搜索用时 31 毫秒
71.
72.
Assembly of materials into microstructures under laser guidance is attracting wide attention. The ability to pattern various materials and form 2D and 3D structures with micron/sub-micron resolution and less energy and material waste compared with standard top-down methods make laser-based printing promising for many applications, for example medical devices, sensors, and microelectronics. Assembly from liquids provides a smaller feature size than powders and has advantages over other states of matter in terms of relatively simple setup, easy handling, and recycling. However, the simplicity of the setup conceals a variety of underlying mechanisms, which cannot be identified simply according to the starting or resulting materials. This progress report surveys the various mechanisms according to the source of the material—preformed or locally synthesized. Within each category, methods are defined according to the driving force of material deposition. The advantages and limitations of each method are critically discussed, and the methods are compared, shedding light on future directions and developments required to advance this field.  相似文献   
73.
Troubleshooting knowledge acquisition is a notorious network maintenance expert systems development bottleneck. We present an improved methodology to generate automatically a skeleton of network troubleshooting knowledge base given the data about network topology, test costs, and network component failure likelihood. Our methodology uses AO * search where a suitable modification of the Huffman code procedure is found to be an admissible heuristic. Our heuristic uses synergistically information about both component failure rates and test costs while relaxing topology constraints. The resulting expert system (XTAR) minimizes expected troubleshooting cost faster and learns better troubleshooting techniques during its operation.  相似文献   
74.
Security analysis of multi-party cryptographic protocols distinguishes between two types of adversarial settings: In the non-adaptive setting the set of corrupted parties is chosen in advance, before the interaction begins. In the adaptive setting the adversary chooses who to corrupt during the course of the computation. We study the relations between adaptive security (i.e., security in the adaptive setting) and nonadaptive security, according to two definitions and in several models of computation.  相似文献   
75.
A multilayer insulation configuration suitable for microwave sintering of ceramics up to 2100°C was designed and tested successfully. The configuration is based on porous, granular BN/ZrO2 fiber composite powder for packed beds and spacer cylinders. This insulation allows stable, controlled microwave sintering and can be modified to microwave process materials with different thermal, dielectric properties with improved properties.  相似文献   
76.
77.
78.
Journal of Housing and the Built Environment - Background Numerous studies have compared self evaluation and market values of apartments by employing hedonic regressions. Most of these studies...  相似文献   
79.

Background

We examined the effect of four weeks of ??-alanine supplementation on isometric endurance of the knee extensors at 45% maximal voluntary isometric contraction (MVIC).

Methods

Thirteen males (age 23?±?6 y; height 1.80?±?0.05?m; body mass 81.0?±?10.5?kg), matched for pre-supplementation isometric endurance, were allocated to either a placebo (n?=?6) or ??-alanine (n?=?7; 6.4?g·d-1 over 4?weeks) supplementation group. Participants completed an isometric knee extension test (IKET) to fatigue, at an intensity of 45% MVIC, before and after supplementation. In addition, two habituation tests were completed in the week prior to the pre-supplementation test and a further practice test was completed in the week prior to the post-supplementation test. MVIC force, IKET hold-time, and impulse generated were recorded.

Results

IKET hold-time increased by 9.7?±?9.4?s (13.2%) and impulse by 3.7?±?1.3 kN·s-1 (13.9%) following ??-alanine supplementation. These changes were significantly greater than those in the placebo group (IKET: t (11)?=?2.9, p ??0.05; impulse: t (11)?=?3.1, p????0.05). There were no significant changes in MVIC force in either group.

Conclusion

Four weeks of ??-alanine supplementation at 6.4?g·d-1 improved endurance capacity of the knee extensors at 45% MVIC, which most likely results from improved pH regulation within the muscle cell as a result of elevated muscle carnosine levels.  相似文献   
80.
A multiplicative secret sharing scheme allows players to multiply two secret-shared field elements by locally converting their shares of the two secrets into an additive sharing of their product. Multiplicative secret sharing serves as a central building block in protocols for secure multiparty computation (MPC). Motivated by open problems in the area of MPC, we introduce the more general notion of d-multiplicative secret sharing, allowing to locally multiply d shared secrets, and study the type of access structures for which such secret sharing schemes exist.  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