全文获取类型
收费全文 | 908篇 |
免费 | 5篇 |
专业分类
电工技术 | 4篇 |
化学工业 | 52篇 |
金属工艺 | 4篇 |
机械仪表 | 17篇 |
建筑科学 | 18篇 |
矿业工程 | 1篇 |
能源动力 | 14篇 |
轻工业 | 34篇 |
水利工程 | 2篇 |
石油天然气 | 8篇 |
无线电 | 77篇 |
一般工业技术 | 85篇 |
冶金工业 | 483篇 |
原子能技术 | 4篇 |
自动化技术 | 110篇 |
出版年
2022年 | 7篇 |
2020年 | 5篇 |
2019年 | 6篇 |
2017年 | 5篇 |
2016年 | 4篇 |
2015年 | 5篇 |
2014年 | 6篇 |
2013年 | 18篇 |
2012年 | 12篇 |
2011年 | 21篇 |
2010年 | 11篇 |
2009年 | 16篇 |
2008年 | 19篇 |
2007年 | 21篇 |
2006年 | 17篇 |
2005年 | 20篇 |
2004年 | 13篇 |
2003年 | 17篇 |
2002年 | 11篇 |
2001年 | 17篇 |
2000年 | 15篇 |
1999年 | 26篇 |
1998年 | 121篇 |
1997年 | 72篇 |
1996年 | 62篇 |
1995年 | 32篇 |
1994年 | 29篇 |
1993年 | 36篇 |
1992年 | 12篇 |
1991年 | 14篇 |
1990年 | 17篇 |
1989年 | 13篇 |
1988年 | 8篇 |
1987年 | 21篇 |
1986年 | 16篇 |
1985年 | 10篇 |
1984年 | 8篇 |
1983年 | 11篇 |
1982年 | 6篇 |
1981年 | 9篇 |
1980年 | 8篇 |
1979年 | 11篇 |
1978年 | 4篇 |
1977年 | 18篇 |
1976年 | 29篇 |
1975年 | 5篇 |
1973年 | 4篇 |
1972年 | 4篇 |
1970年 | 4篇 |
1968年 | 4篇 |
排序方式: 共有913条查询结果,搜索用时 0 毫秒
1.
Rosenberg Florian Curbera Francisco Duftler Matthew J. Khalaf Rania 《Internet Computing, IEEE》2008,12(5):24-31
The use of RESTful Web services has gained momentum in the development of distributed applications based on traditional Web standards such as HTTP. In particular, these services can integrate easily into various applications, such as mashups. Composing RESTful services into Web-scale workflows requires a lightweight composition language that's capable of describing both the control and data flow that constitute a workflow. The authors address these issues with Bite, a lightweight and extensible composition language that enables the creation of Web-scale workflows and uses RESTful services as its main composable entities. 相似文献
2.
Hartung J. Jacquin A. Pawlyk J. Rosenberg J. Okada H. Crouch P.E. 《Selected Areas in Communications, IEEE Journal on》1998,16(1):42-55
This paper describes a prototype video coding platform meant for the conception and testing of multimedia products such as next-generation videophones. The platform is largely based on ITU-T Recommendation H.263, with a number of additional object-oriented quality enhancement features which make it especially well suited for very low bit-rate coding of “head-and-shoulders” video material typical of real-time multimedia applications, video teleconferencing, and video telephony. These features consist of: (1) segmentation into objects of interest, (2) segmentation-based prefiltering, (3) model-assisted rate control, (4) adaptive vector quantization, and finally (5) segmentation-based postfiltering. In the spirit of Recommendation H.263, these enhancements are modular and can be selectively turned on or off, thereby enabling a wide variety of coding modes 相似文献
3.
Michel Gangnet Burton Rosenberg 《Annals of Mathematics and Artificial Intelligence》1993,8(3-4):271-284
Aconstraint system includes a set of variables and a set of relations among these variables, calledconstraints. The solution of a constraint system is an assignment of values to variables so that all, or many, of the relations are made true. A simple and efficient method for constraint resolution has been proposed in the work of B.N. Freeman-Benson, J. Maloney, and A. Borning. We show how their method is related to the classical problem of graph matching, and from this connection we derive new resolution algorithms. 相似文献
4.
5.
RS Strobel AK Nagy AF Knowles J Buegel MD Rosenberg 《Canadian Metallurgical Quarterly》1996,271(27):16323-16331
An ecto-ATP diphosphohydrolase (ATPDase) was purified to homogeneity from vesiculosomes shed from chicken oviduct. First, the ecto-ATPDase-enriched vesiculosomes were concentrated by filtration, differential centrifugation, and exclusion chromatography. Next, the nonionic detergent, Nonidet P-40, was used to extract the ecto-ATPDase from vesiculosomal membranes, and the solubilized enzyme was further purified by ion exchange (DEAE-Bio-Gel) and lentil-lectin-Sepharose 4B chromatography. In the final stage, immunoaffinity chromatography was utilized to obtain purified ecto-ATPDase. More than 25,000-fold purification was achieved. Specific activity of the purified enzyme was greater than 800 micronol/min/mg of protein with MgATP as the substrate, the highest ever reported for an ATPDase. The enzyme also hydrolyzed other nucleoside triphosphates in the presence of magnesium at similar rates and CaATP and MgADP at lower rates. The molecular mass of the purified glycoprotein was 80 kDa as determined by SDS-polyacrylamide gel electrophoresis and Western blot analysis. Based on its enzymatic properties, the relationship of the chicken oviduct ecto-ATPDase with other reported ATPDases and ecto-ATPases is discussed. 相似文献
6.
7.
8.
This paper presents an analysis of the sensitivity of coupled resonator filters in which some direct couplings are missing. The effect of changes in the coupling coefficients and resonant frequencies of the resonators is investigated by directly computing the gradient of the scattering parameters. It is shown that structures that are modular in the input-to-output direction are much less sensitive than those with modularity in the orthogonal direction for the same frequency response. 相似文献
9.
Early federal injury control programs in the 1960s and 1970s were centered first in the Division of Accident Prevention (Public Health Service) and subsequently in the National Highway Traffic Safety Administration (Department of Transportation) and the Consumer Product Safety Commission. The Centers for Disease Control (CDC) in the early 1970s also began to investigate injuries, particularly in the home and recreational environment. The field expanded in the 1970s and 1980s to include injuries that occur in many settings and both intentional injuries (violence) and unintentional injuries. After a 1985 report, Injury in America, CDC was chosen to be the national coordinating agency because of its mission of prevention. The current program also includes acute care, rehabilitation, and biomechanics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
A novel band-reject element for the design of inline waveguide pseudoelliptic band-reject filters is introduced. The element consists of an offset partial-height post in a rectangular waveguide in which the dominant TE10 mode is propagating. The location of the attenuation pole is primarily determined by the height of the post that generates it. The element allows the implementation of weak, as well as strong coupling coefficients that are encountered in asymmetric band-reject responses with broad stopbands. The coupling strength is controlled by the offset of the post with respect to the center of the main waveguide. The posts are separated by uniform sections of the main waveguide. An equivalent low-pass circuit based on the extracted pole technique is first used in a preliminary design. An improved equivalent low-pass circuit that includes a more accurate equivalent circuit of the band-reject element is then introduced. A synthesis method of the enhanced network is also presented. Filters based on the introduced element are designed, fabricated, and tested. Good agreement between measured and simulated results is achieved 相似文献