全文获取类型
收费全文 | 465篇 |
免费 | 23篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 8篇 |
化学工业 | 128篇 |
金属工艺 | 7篇 |
机械仪表 | 10篇 |
建筑科学 | 11篇 |
能源动力 | 28篇 |
轻工业 | 22篇 |
水利工程 | 7篇 |
无线电 | 33篇 |
一般工业技术 | 139篇 |
冶金工业 | 23篇 |
原子能技术 | 3篇 |
自动化技术 | 72篇 |
出版年
2024年 | 3篇 |
2023年 | 6篇 |
2022年 | 12篇 |
2021年 | 20篇 |
2020年 | 19篇 |
2019年 | 13篇 |
2018年 | 26篇 |
2017年 | 26篇 |
2016年 | 32篇 |
2015年 | 13篇 |
2014年 | 13篇 |
2013年 | 39篇 |
2012年 | 31篇 |
2011年 | 49篇 |
2010年 | 15篇 |
2009年 | 17篇 |
2008年 | 24篇 |
2007年 | 14篇 |
2006年 | 15篇 |
2005年 | 5篇 |
2004年 | 11篇 |
2003年 | 6篇 |
2002年 | 4篇 |
2001年 | 4篇 |
2000年 | 7篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1994年 | 7篇 |
1993年 | 5篇 |
1992年 | 2篇 |
1991年 | 5篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1987年 | 7篇 |
1986年 | 3篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1976年 | 3篇 |
排序方式: 共有491条查询结果,搜索用时 40 毫秒
1.
2.
Rodolfo Matamoros Gerald R. Graves Avinash Waikar Magd Zohdi 《Computers & Industrial Engineering》1989,16(4):515-523
The computer industry has evolved very rapidly from single-user computers to computer networks where users are able to share both local and remote files. Networks of microcomputers facilitate the integration of all information processing for distributed applications such as database processing and electronic mail. One management application of promising potential for computer networks is distributed simulation. Simulation analysis can be useful to essentially all problem-solving and decision-making on the job.
To implement a particular distributed application, computer communication between processors must be considered. Unlike expensive multiprocessor computers, networks of less-expensive microcomputers do not have pre-established communication paths between processors. This paper addresses how this obstacle may be overcome by using communication protocols based on the Open Systems Interconnection (OSI) reference model. Protocol services needed to support a distributed simulation environment will be identified, and their implementation through a prototype will then be investigated and evaluated. 相似文献
3.
The sorption of n-alkanes, viz. hexane, heptane and octane by cross-linked natural rubber/poly(ethylene-co-vinyl acetate) (NR/EVA) blends has been studied at 28, 38, 48 and 58°C, with special reference to the effects of EVA content,
cross-linking systems, penetrant nature and temperature. The solvent transport was found to decrease with increase in EVA
content in the blends. The effects of blend ratio on the transport characteristics have been correlated with the phase morphology
of the blends, using scanning electron micrographs and optical micrographs. Among the three vulcanising systems, viz. sulphur
(S), dicumyl peroxide (DCP) and a mixed system (S + DCP) employed for the matrix, the DCP cross-linked blends exhibited the
lowest solvent uptake. Octane has been found to show higher interaction with the blends than hexane and heptane, probably
owing to the closer solubility parameter values. The computed transport coefficients, viz. diffusion coefficient and permeability
coefficient, were found to decrease with increase in EVA content in the blends. At room temperature, the mechanism of diffusion
was found to deviate slightly from the regular Fickian trend for all blend systems. The blend–solvent interaction parameter
and the activation energy for transport were also determined from the sorption data. 相似文献
4.
Blends based on ethylene–propylene–diene monomer rubber (EPDM) and acrylonitrile butadiene rubber (NBR) was prepared. Sulfur was used as the vulcanizing agent. The effects of blend ratio on the cure characteristics and mechanical properties, such as stress–strain behavior, tensile strength, elongation at break, hardness, rebound resilience, and abrasion resistance have been investigated. Tensile and tear strength showed synergism for the blend containing 30% of NBR, which has been explained in terms of morphology of the blends attested by scanning electron micrographs. A relatively cocontinuous morphology was observed for 70 : 30, EPDM/NBR blend system. The experimental results have been compared with the relevant theoretical models. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
5.
Avinash Kumar Agarwal Ashish Garg Mritunjay Kumar Shukla 《Surface & coatings technology》2007,201(13):6182-6188
This paper reports tribological characterization of titanium based coatings ion bonded on steel balls for automotive applications using exhaust gas recirculation (EGR). It is well known that lubricating oil drawn from EGR operated engine is contaminated with soot and higher amounts of wear debris compared to non-EGR operated engine. In this study, steel balls coated with TiN, TiAlN and TiCN are investigated in both fresh lubricating oil and EGR stressed oil for a comparative assessment of their wear characteristics in two mediums. Normal load was applied on the samples, tested against a rotating cast iron disk, simulating ring-liner interaction. In each experiment, about one quarter of disk was dipped in the oil (a) to ensure the presence of a thin oil film on the disk-ball interface during the experiment, and (b) to avoid exposure of the worn surface to atmospheric air. The results reveal that the wear rates of the coatings based on the change in the scar diameters of the samples, tested in EGR oil was 2-4 times higher than that of fresh lubricating oil. It was found that despite lowest hardness, TiN coated samples showed smaller scar diameters than TiAlN and TiCN coated samples in both lubricating oil environments. A simple geometric model was used to calculate the thickness of the coating removed as a function of the test duration. Results show that TiN coatings last for 120 min in fresh oil as compared to 30 min in the EGR oil under normal loading, whereas TiAlN and TiCN coating last for 60 and 30 min respectively in fresh oil and wear out in 15 min in EGR oil. 相似文献
6.
7.
8.
Avinash W. Kadam 《Information Security Journal: A Global Perspective》2013,22(5):246-256
ABSTRACT Development of the information security policy is a critical activity. Credibility of the entire information security program of an organization depends upon a well-drafted information security policy. Most of the stakeholders do not have time or inclination to wade through a lengthy policy document. This article tries to formulate an approach to the information security policy development that will make the policy document capture the essentials of information security as applicable to a business. The document will also convey the urgency and importance of implementing the policy, not only in letter but also in spirit. 相似文献
9.
Although CAD tools have significantly assisted electronic system simulation, the system-level optoelectronics modeling field has lagged behind due to a lack of simulation methodologies and tools. Optisim, a system-level modeling and simulation methodology of optical interconnects for HPC systems, can provide computer architects, designers, and researchers with a highly optimized, efficient, and accurate discrete-event environment to test various HPC systems. 相似文献
10.
Avinash Unnikrishnan Varunraj Valsaraj Steven Travis Waller 《Networks and Spatial Economics》2009,9(4):525-550
The focus of this work is to determine the optimal storage capacity to be installed on transhipment nodes by shippers in a
dynamic shipper carrier network under stochastic demand. A two stage linear program with recourse formulation is developed
where in the first stage, the shipper decides the optimal capacity to be installed on transhipment nodes. In the second stage,
the shipper chooses a routing strategy based on the realized demand. The performance of the following solution methods: Stochastic
L Shaped Method, Regularized Decomposition and L Shaped Method with preliminary cuts were compared for various network sizes
and numerous demand scenarios. A novel capacity shifting heuristic was introduced to generate a feasible implementable solution
which significantly improves the performance of Regularized Decomposition and provides the best performance in the cases tested.
Various ways of generating analytical bounds on the objective function value was discussed. The new capacity shifting heuristic
was found to be efficient in generating tight upper bounds. Even though the formulation considered in this paper is for a
single commodity, the model can be easily extended to account for multiple commodities. 相似文献