全文获取类型
收费全文 | 151篇 |
免费 | 1篇 |
专业分类
化学工业 | 9篇 |
金属工艺 | 1篇 |
机械仪表 | 1篇 |
建筑科学 | 1篇 |
轻工业 | 8篇 |
无线电 | 50篇 |
一般工业技术 | 19篇 |
冶金工业 | 21篇 |
原子能技术 | 2篇 |
自动化技术 | 40篇 |
出版年
2023年 | 2篇 |
2021年 | 2篇 |
2020年 | 2篇 |
2018年 | 4篇 |
2016年 | 2篇 |
2015年 | 3篇 |
2014年 | 6篇 |
2013年 | 5篇 |
2012年 | 6篇 |
2011年 | 12篇 |
2010年 | 5篇 |
2009年 | 4篇 |
2008年 | 16篇 |
2007年 | 14篇 |
2006年 | 23篇 |
2005年 | 7篇 |
2004年 | 1篇 |
2003年 | 5篇 |
2002年 | 1篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 7篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1991年 | 2篇 |
1987年 | 2篇 |
1981年 | 2篇 |
1976年 | 2篇 |
1973年 | 1篇 |
1970年 | 2篇 |
1958年 | 1篇 |
排序方式: 共有152条查询结果,搜索用时 15 毫秒
21.
A Stimulation Method to Assess the Contractile Status of the Lumbar Extensors in a Seated Posture 下载免费PDF全文
The purpose of present study was to develop and evaluate methods to assess stimulation responses of the lumbar extensors, as part of a longer‐term goal of detecting fatigue during prolonged sitting. Three stimulation frequencies (2, 5, and 8 Hz) were tested in separate stages, which include 3 stimulation trains and 4 sampling blocks. Repeated measures analyses of variance were used to determine whether any significant differences in mean stimulation responses occurred with respect to stimulation frequency, sampling block, and stimulation train. Reliability of measured stimulation responses was assessed within and between sampling blocks using intraclass correlation coefficients. Stimulation frequencies significantly affected the stimulation responses and time‐to‐potentiation differed between the 3 stimulation frequencies; it was highest for 2 Hz stimulation. All 3 stimulation frequencies resulted in excellent reliability within and between sampling blocks. Use of the current protocol at 2 Hz is recommended as appropriate to measure the lumbar extensors status during prolonged sitting. 相似文献
22.
General-purpose database management systems, whose structure is built in, are not an appropriate solution to situations where problems of translation or areas of research cannot be bounded in advance, for example, when lexicography and linguistic research are closely related. Consequently, an original system has been developed, and is being applied to linguistic and lexicographical data on the Somali language.Jacqueline Lecarme has a master's degree in Lettres Classiques (University of Grenoble, 1969) and a Ph.D. in linguistics (University of Montreal, 1978). Carole Maury has a master's degree and a doctorate in computer science (University of Nice, 1986). 相似文献
23.
Nascimento Sidnei Gouvêa Maury M. 《International Journal of Control, Automation and Systems》2021,19(7):2596-2610
International Journal of Control, Automation and Systems - Problems with two or more conflicting objectives have been handled as needing a multi-objective approach in recent years. The solution for... 相似文献
24.
Maury Wright 《电子设计技术》2008,15(4):50-52,54,56
设计者采用能感知调制方法的测试工具推进下一代无线系统的开发,尽管新兴标准引入了一些PHY层和数据层的问题。 相似文献
25.
Maury Wright 《电子设计技术》2007,14(10):28-28
我曾为需要能够在整个家庭输送高清电视流的低成本联网技术这个问题所困扰.我仍然相信视频联网应用将为从集成电路供应商到服务提供商以及信息拥有者带来巨大收益. 相似文献
26.
Steven E. Koonin George F. Carrier Robert F. Christy Robert W. Conn Ronald C. Davidson John M. Dawson Anthony J. DeMaria Paul M. Doty William Happer Jr. Gerald L. Kulcinski Conrad L. Longmire James R. Powell Jr. Marshall N. Rosenbluth Jack P. Ruina Robert L. Sproull Maury Tigner Richard L. Wagner 《Journal of Fusion Energy》1991,10(2):157-172
27.
Dispersion fiber sensitivity in optical microwave upconversion links is investigated. Simulations are carried out to calculate output optical spectra and to evaluate mixing power as a function of fiber length for different upconversion systems using dual drive/standard Mach-Zehnder modulators or an unbalanced Mach-Zehnder interferometer (UMZ). The latter solution prevents complete cancellation of mixing power because of the asymmetric double sideband optical spectrum detected at the output of the UMZ. It is shown that an optimum value of the linewidth enhancement factor of the laser diode can be found to minimize degradations of the mixing power along the fiber. 相似文献
28.
29.
Daily IFN-alpha/beta therapy was totally ineffective in inhibiting the development of visceral metastases in DBA/2 mice injected i.v. with the ESb lymphoma regardless of the number of tumor cells injected. The finding that IFN-alpha/beta therapy increased the survival time of ESb-immunized mice rechallenged with ESb cells suggested that cooperation between the immune system and IFN-alpha/beta was important. Adoptive transfer of Esb-immune spleen cells (but not normal cells) together with IFN-alpha/beta treatment did inhibit the development of ESb metastases in immunocompetent DBA/2 mice. Either treatment alone was ineffective. The anti-metastatic effect was specific for the ESb lymphoma as spleen cells from ESb-immunized mice together with IFN-alpha/beta treatment did not inhibit the development of metastases in mice challenged with IFN-alpha/beta-resistant 3C18 FLC. Depletion of CD8+ T cells (but not CD4+ T cells or B lymphocytes) prior to transfer eliminated the protective effect of ESb-immune splenocytes in IFN-alpha/beta-treated mice. As few as 1 x 10(6) ESb-immune spleen cells highly enriched for CD8+ cells increased the survival time of IFN-alpha/beta-treated ESb-challenged DBA/2 mice. The combined therapy of ESb-specific immune cells and IFN-alpha/beta resulted in long-term immunity to this tumor. 相似文献
30.
Chromium carbide coatings were grown at 748 K in a hot wall CVD reactor fed by sublimation of bis(benzene)chromium, BBC (MOCVD) and by direct liquid injection using a BBC/toluene solution (DLICVD). The two types of coatings exhibit an amorphous structure and the same C content (22 at.%). DLICVD permits delivering higher mass flow rate of precursors and consequently the growth rate is 3 times higher and the thickness uniformity is better than using MOCVD. Chromium metal deposition has also been investigated by DLICVD in this hot wall reactor using BBC/toluene/additive as precursor. The purpose of the additive is to block carbide formation. Two additives have been studied: (i) hexachlorobenzene (C6Cl6) and (ii) thiophenol (C6H5SH). The ratio additive/BBC required for Cr metal deposition is a few percent. In this process, C6Cl6 is not decomposed and only traces of Cl (0.4 at.%) are found in the coatings. For a ratio C6Cl6/BBC > 27% the growth of any coating is blocked. The gas phase containing C6H5SH is more reactive since the onset of deposition occurs approximately 50 K before the temperature of the chlorinated compound. Furthermore, a sulfur contamination of 3 at.% has been analyzed in the coatings revealing a partial decomposition of the additive. The results are detailed and discussed in relation with previous works. 相似文献