全文获取类型
收费全文 | 259篇 |
免费 | 12篇 |
专业分类
电工技术 | 6篇 |
化学工业 | 62篇 |
金属工艺 | 1篇 |
机械仪表 | 12篇 |
建筑科学 | 8篇 |
能源动力 | 10篇 |
轻工业 | 35篇 |
水利工程 | 2篇 |
无线电 | 37篇 |
一般工业技术 | 28篇 |
冶金工业 | 2篇 |
原子能技术 | 1篇 |
自动化技术 | 67篇 |
出版年
2023年 | 4篇 |
2022年 | 11篇 |
2021年 | 11篇 |
2020年 | 7篇 |
2019年 | 13篇 |
2018年 | 9篇 |
2017年 | 7篇 |
2016年 | 11篇 |
2015年 | 13篇 |
2014年 | 15篇 |
2013年 | 28篇 |
2012年 | 19篇 |
2011年 | 25篇 |
2010年 | 13篇 |
2009年 | 13篇 |
2008年 | 20篇 |
2007年 | 11篇 |
2006年 | 4篇 |
2005年 | 6篇 |
2004年 | 4篇 |
2003年 | 5篇 |
2002年 | 7篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1988年 | 2篇 |
1986年 | 1篇 |
1982年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有271条查询结果,搜索用时 0 毫秒
91.
Dejan M. Bošković Andras Balogh Miroslav Krstić 《Mathematics of Control, Signals, and Systems (MCSS)》2003,16(1):44-75
In this paper a family of stabilizing boundary feedback control laws for a class of linear parabolic PDEs motivated by engineering
applications is presented. The design procedure presented here can handle systems with an arbitrary finite number of open-loop
unstable eigenvalues and is not restricted to a particular type of boundary actuation. Stabilization is achieved through the
design of coordinate transformations that have the form of recursive relationships. The fundamental difficulty of such transformations
is that the recursion has an infinite number of iterations. The problem of feedback gains growing unbounded as the grid becomes
infinitely fine is resolved by a proper choice of the target system to which the original system is transformed. We show how
to design coordinate transformations such that they are sufficiently regular (not continuous but L
∞). We then establish closed-loop stability, regularity of control, and regularity of solutions of the PDE. The result is accompanied
by a simulation study for a linearization of a tubular chemical reactor around an unstable steady state.
Date received: June 22, 2001. Date revised: January 17, 2002.
RID="*"
ID="*"This work was supported by grants from AFOSR, ONR, and NSF. 相似文献
92.
Dejan Bosanac 《程序员》2006,(5):94-97
在本文中,作者将给出一些Spring MVC框架的配置技巧,这些技巧可以帮助您管理基于Sping的web应用程度的多个实例。它与任何特定技术没有直接关联,所以我们将从解释问题的基本概念开始。接下来,作者将重点讲述Spring MVC框架,差为使用此项技本开发的项目提供一些解决方案。 相似文献
93.
Filipa S. Reis Ana Ćirić Dejan Stojković Lillian Barros Milica Ljaljević-Grbić 《Drug development and industrial pharmacy》2015,41(2):253-262
The genus Penicillium is well known for its importance in drug and food production. Certain species are produced on an industrial scale for the production of antibiotics (e.g. penicillin) or for insertion in food (e.g. cheese). In the present work, three Penicillium species, part of the natural mycobiota growing on various food products were selected – P. ochrochloron, P. funiculosum and P. verrucosum var. cyclopium. The objective of our study was to value these species from the point of view of production of bioactive metabolites. The species were obtained after inoculation and growth in Czapek and Malt media. Both mycelia and culture media were analyzed to monitor the production of different metabolites by each fungus and their release to the culture medium. The concentrations of sugars, organic acids, phenolic acids and tocopherols were determined. Antioxidant activity of the phenolic extracts was evaluated, as also the antimicrobial activity of phenolic acids, organic acids and tocopherols extracts. Rhamnose, xylose, fructose and trehalose were found in all the mycelia and culture media; the prevailing organic acids were oxalic and fumaric acids, and protocatechuic and p-hydroxybenzoic acids were the most common phenolic acids; γ-tocopherol was the most abundant vitamin E isoform. Generally, the phenolic extracts corresponding to the mycelia samples revealed higher antioxidant activity. Concerning the antimicrobial activity there were some fluctuations, however all the studied species revealed activity against the tested strains. Therefore, the in-vitro bioprocesses can be an alternative for the production of bioactive metabolites that can be used by pharmaceutical industry. 相似文献
94.
Basalt has remarkable physical and mechanical characteristics. However, its use and further processing is limited due to mechanical characteristics, e.g., density, hardness, fraying resistance, etc. The basalt–polymer composite enable maintains of physical and mechanical characteristics, further processing, and broader basalt application in various industries. Consequently, composites characterization, and production process technological parameters influence on the composites properties need to be appraised. 相似文献
95.
96.
Special events such as music festivals, sports etc are characterised as “high user density” where user behaviour is determined by the dynamics of the event. This is the reason that it is necessary for a mobile network operator to dimension its network based on maximum expected resource requirements instead on averaged values. Although special events are taking place almost every week, in most cases not enough attention has been paid to the problem of resource dimensioning in the Universal Mobile Telecommunications System networks, and the appropriate cost function to equate the optimal quantities resources has not been developed. It is therefore necessary to be aware that special events networks should be dimensioned with the maximum resource requirements, using distributed antenna system (DAS) where possible, and the consolidated baseband processing resources. Appropriate cost function will be used to describe optimal design that should depend on the number of sectors needed, radio network controller and the overall network capacity. A suitable radio access network (RAN) analysis has been performed and a cost function has been developed in order to create the metrics that can be used for evaluating the cost of dimensioning the RAN in special events. It can be shown based on proposed metrics that 10 % of savings in resources could be achieved by degrading the grade of service less than 1 %. 相似文献
97.
Radovanović Slobodan Ranković Vesna Anđelković Vladimir Divac Dejan Milivojević Nikola 《Bulletin of Engineering Geology and the Environment》2018,77(3):1191-1202
Bulletin of Engineering Geology and the Environment - Knowledge of the deformation properties of the rock mass is essential for the stress–strain analysis of structures such as dams, tunnels,... 相似文献
98.
99.
本文中,作者讨论了某些蓄水池中的水的侵蚀性的测定问题,如“Zlatibor”、“Gruza”和“Barje”。由于腐蚀性水会导致许多问题,因此,这个问题是非常重要的。作者分析了如何使腐蚀性水稳定。本文还介绍了用于腐蚀分析的数学模板。 相似文献
100.
In this paper, the performance of turbo coding in WCDMA downlink is considered in conjunction with receivers using two adaptive
channel equalizers. Bit error and frame error rates are compared to the performance of the conventional Rake receiver. Special
consideration is given to the cases with two receive antennas, the efficiency of the channel interleaver, the number of iterations
in decoding, the performance with various numbers of users, the influence of mobile receiver velocity as well as to the effect
of power control. The simulation results show that turbo coding, combined with power control and channel equalizers is a very
efficient way to implement reliable data transmissions in WCDMA downlink. The results in the paper also verify that the adaptive
channel equalizers is a very promising technique to improve the receiver performance and increase the user capacity. 相似文献