全文获取类型
收费全文 | 943篇 |
免费 | 25篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 8篇 |
化学工业 | 157篇 |
金属工艺 | 40篇 |
机械仪表 | 13篇 |
建筑科学 | 45篇 |
矿业工程 | 2篇 |
能源动力 | 21篇 |
轻工业 | 48篇 |
水利工程 | 11篇 |
石油天然气 | 3篇 |
无线电 | 99篇 |
一般工业技术 | 129篇 |
冶金工业 | 257篇 |
原子能技术 | 6篇 |
自动化技术 | 130篇 |
出版年
2023年 | 8篇 |
2022年 | 10篇 |
2021年 | 14篇 |
2020年 | 14篇 |
2019年 | 17篇 |
2018年 | 20篇 |
2017年 | 9篇 |
2016年 | 18篇 |
2015年 | 8篇 |
2014年 | 19篇 |
2013年 | 43篇 |
2012年 | 25篇 |
2011年 | 39篇 |
2010年 | 17篇 |
2009年 | 24篇 |
2008年 | 30篇 |
2007年 | 33篇 |
2006年 | 34篇 |
2005年 | 20篇 |
2004年 | 16篇 |
2003年 | 27篇 |
2002年 | 16篇 |
2001年 | 21篇 |
2000年 | 11篇 |
1999年 | 23篇 |
1998年 | 69篇 |
1997年 | 25篇 |
1996年 | 30篇 |
1995年 | 11篇 |
1994年 | 17篇 |
1993年 | 25篇 |
1992年 | 19篇 |
1991年 | 17篇 |
1990年 | 7篇 |
1989年 | 15篇 |
1988年 | 16篇 |
1987年 | 12篇 |
1986年 | 10篇 |
1985年 | 20篇 |
1984年 | 13篇 |
1983年 | 10篇 |
1982年 | 14篇 |
1981年 | 17篇 |
1980年 | 7篇 |
1979年 | 4篇 |
1978年 | 8篇 |
1977年 | 13篇 |
1976年 | 18篇 |
1975年 | 8篇 |
1973年 | 5篇 |
排序方式: 共有969条查询结果,搜索用时 0 毫秒
81.
Austin S. Babrow 《The Journal of communication》2001,51(3):453-455
82.
83.
M de Abood Z de Castillo F Guerrero M Espino KL Austin 《Canadian Metallurgical Quarterly》1997,56(5):313-316
Forty-three homozygous (SS) female sickle cell anemic patients with a history of at least one painful crisis per month and desiring a reversible contraceptive were administered DMPA/3 months or Microgynon monthly. A third group of 16 surgically sterilized patients served as control. Patients were followed for 1 year to assess possible effects of the contraceptives on the patients' painful crises. No changes were observed in any of the groups in the hematological parameters. At the end of the study, 70% of the patients receiving DMPA were pain-free and only 16% of those still reporting painful crises rated them as intense. Patients receiving Microgynon also had an amelioration of the painful crises, although at a lower rate; after 12 months, 45.5% still experienced some crises. Although less marked than in the other groups, 50.5% of the control patients also reported an improvement of their painful crisis, which may be a result of closer medical care. 相似文献
84.
Y. Austin Chang 《Journal of Phase Equilibria》1989,10(5):513-521
Phase equilibria at temperatures above and below the tricritical point of binary alloys are discussed in terms of thermodynamic principles. The existence of a second spinodal curve for the disordered phase within the magnetic-induced miscibility gap is rationalized. The relative interplay of the chemical and magnetic contributions to the stabilities of various types of phase equilibria in binary alloys is also discussed. The effect of magnetic contribution to the Fe?Ni and Fe-Ni-Cr phase stabilities at low temperatures is reviewed. The calculated phase diagrams of the Fe?Ni and Fe-Ni-Cr systems considering the magnetic and nonmagnetic terms are compared with experimental results. These results were obtained either from meteorites or from synthesized alloys subjected to irradiation. The meteorites, which have cooled slowly in space, may have achieved metastable/stable equilibrium conditions. The many defects introduced by irradiation for the synthesized alloys may have helped to achieve metastable/stable equilibrium conditions. 相似文献
85.
An improved Prony algorithm, code-named SVDP (singular value decomposition Prony), is proposed for identifying discrete multipath components. The new technique has been applied to data obtained from both laboratory and field experiments. The superiority of the algorithm in determining the number of rays present, and also in resolving close rays, is demonstrated. 相似文献
86.
Memorializes Frederic Kuder, known for his work in developing interest measurements. His early research was chiefly on test construction and statistics, and later he published on the measurement of interests, appropriate instruments to measure interests, and the results of such research. He developed the Kuder Occupational Interest Survey and Kuder Preference Record. The interest inventories were instrumental in the growth of Science Research Associates into a major publisher of tests and instructional products. They eventually grew to 4 distinctly different forms in 7 editions, estimated to have been completed by 100 million persons worldwide. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
James Bliss Austin 《Journal of the American Ceramic Society》1931,14(11):795-810
The thermal expansion of crystals of alpha-alumina, magnesia, chromite, mullite, and zircon and of a mass of fused zirconia has been measured up to 1000°C. The results are exhibited in tables and in graphical form. 相似文献
88.
Austin J. Davis R. Fletcher M. Jackson T. Jessop M. Liang B. Pasley A. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2005,93(3):496-509
The use of search engines within the Internet is now ubiquitous. This work examines how Grid technology may affect the implementation of search engines by focusing on the Signal Data Explorer application developed within the Distributed Aircraft Maintenance Environment (DAME) project. This application utilizes advanced neural-network-based methods (Advanced Uncertain Reasoning Architecture (AURA) technology) to search for matching patterns in time-series vibration data originating from Rolls-Royce aeroengines (jet engines). The large volume of data associated with the problem required the development of a distributed search engine, where data is held at a number of geographically disparate locations. This work gives a brief overview of the DAME project, the pattern marching problem, and the architecture. It also describes the Signal Data Explorer application and provides an overview of the underlying search engine technology and its use in the aeroengine health-monitoring domain. 相似文献
89.
Hanson S. Bo Zhai Mingoo Seok Cline B. Zhou K. Singhal M. Minuth M. Olson J. Nazhandali L. Austin T. Sylvester D. Blaauw D. 《Solid-State Circuits, IEEE Journal of》2008,43(4):881-891
In this study, we explore the design of a subthreshold processor for use in ultra-low-energy sensor systems. We describe an 8-bit subthreshold processor that has been designed with energy efficiency as the primary constraint. The processor, which is functional below Vdd=200 mV, consumes only 3.5 pJ/inst at Vdd=350 mV and, under a reverse body bias, draws only 11 nW at Vdd=160 mV. Process and temperature variations in subthreshold circuits can cause dramatic fluctuations in performance and energy consumption and can lead to robustness problems. We investigate the use of body biasing to adapt to process and temperature variations. Test-chip measurements show that body biasing is particularly effective in subthreshold circuits and can eliminate performance variations with minimal energy penalties. Reduced performance is also problematic at low voltages, so we investigate global and local techniques for improving performance while maintaining energy efficiency. 相似文献
90.