全文获取类型
收费全文 | 101篇 |
免费 | 11篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 4篇 |
综合类 | 2篇 |
化学工业 | 15篇 |
金属工艺 | 2篇 |
建筑科学 | 6篇 |
矿业工程 | 5篇 |
能源动力 | 1篇 |
轻工业 | 5篇 |
水利工程 | 1篇 |
石油天然气 | 3篇 |
无线电 | 14篇 |
一般工业技术 | 20篇 |
冶金工业 | 11篇 |
自动化技术 | 25篇 |
出版年
2024年 | 2篇 |
2022年 | 7篇 |
2021年 | 4篇 |
2020年 | 5篇 |
2019年 | 5篇 |
2018年 | 1篇 |
2017年 | 3篇 |
2016年 | 2篇 |
2015年 | 9篇 |
2014年 | 3篇 |
2013年 | 8篇 |
2012年 | 6篇 |
2010年 | 4篇 |
2009年 | 1篇 |
2008年 | 1篇 |
2006年 | 1篇 |
2005年 | 4篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 4篇 |
2000年 | 4篇 |
1999年 | 2篇 |
1998年 | 6篇 |
1997年 | 4篇 |
1996年 | 5篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 4篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1982年 | 2篇 |
1968年 | 1篇 |
排序方式: 共有114条查询结果,搜索用时 15 毫秒
1.
近年来,国内外数据泄露事件频发,大量企业的商业利益、声誉受损。数据安全法律法规相继颁布,监管力度不断升级,企业逐渐意识到数据安全治理的重要性与紧迫性。通过对2021年开展的企业数据安全治理能力评估现状进行整理,总结企业数据安全治理工作在组织建设、人才培养、技术工具等方面的现状与趋势,提供能力提升思路,以供业界参考。 相似文献
2.
Consider a flexible manufacturing system (FMS), with several parallel production lines. Each line is statistically balanced. Due to process time and yield variations, some workstations may be temporarily starved of parts during the FMS operation, while others may have too many. The purpose of the dynamic routing algorithm described here is to achieve real-time load balancing in a stochastic processing environment and thus to increase the performance of the system in throughput, workload balance and reduced work-in-process queues. We formulate the problem and develop an optimal stationary policy (for two lines that have a material handling transport between them) based on the input buffer state of each station. 相似文献
3.
Mina Shiran Chaharsoughi Dan Zhao Xavier Crispin Simone Fabiano Magnus P. Jonsson 《Advanced functional materials》2019,29(28)
Sensors for monitoring temperature, heat flux, and thermal radiation are essential for applications such as electronic skin. While pyroelectric and thermoelectric effects are suitable candidates as functional elements in such devices, both concepts show individual drawbacks in terms of zero equilibrium signals for pyroelectric materials and small or slow response of thermoelectric materials. Here, these drawbacks are overcome by introducing the concept of thermodiffusion‐assisted pyroelectrics, which combines and enhances the performance of pyroelectric and ionic thermoelectric materials. The presented integrated concept provides both rapid initial response upon heating and stable synergistically enhanced signals upon prolonged exposure to heat stimuli. Likewise, incorporation of plasmonic metasurfaces enables the concept to provide both rapid and stable signals for radiation‐induced heating. The performance of the concept and its working mechanism can be explained by ion–electron interactions at the interface between the pyroelectric and ionic thermoelectric materials. 相似文献
4.
The structure and luminescent properties of lightly doped CaF2:Pr crystals and Ca0.65Pr0.35F2.35 solid solution have been studied. The results demonstrate that the evolution of the emission spectra of the crystals with increasing PrF3 concentration can be understood in terms of the structural changes in the fluorite solid solutions, namely, the formation of defect clusters. 相似文献
5.
CD317 (Tetherin,BST-2或HM1.24)于1994年被发现并命名,是终末分化B细胞的特异性表面标志.2008年首次被鉴定为干扰素诱导型宿主抗病毒因子,此后越来越多的科学家加入到该领域的探索中.经过近十年的研究,目前已经阐述了CD317结构、抗病毒及免疫特性等问题,也陆续发现了一些诸如参与肿瘤进展、束缚外泌体释放等新功能,研究热度不减当年.因此,文章对近几年CD317功能的研究进展进行一个系统的总结,以期为病毒感染、肿瘤发病以及治疗等方面的理论进步和技术发展提供新的思路. 相似文献
6.
E. Khmelnitsky K. Kogan O. Maimon 《International Transactions in Operational Research》1995,2(4):331-339
This paper introduces a new approach to continuous-time optimal scheduling problems for a large class of manufacturing systems. This class belongs to a make-to-order production environment, based on multi-level bills of materials, flexible flow shops with setup effects and finite capacities on the shop floor. So far the setup and production planning had to be decomposed into two levels; the present model allows treating these two issues on one level, thus potentially achieving better production results. The proposed approach states the problem in terms of optimal control and investigates control strategies by means of the maximum principle for the problems with constraints on state variables. A numerical method concludes this investigation, sustaining the effectiveness of the approach on a robotic cell example.* 相似文献
7.
Low-level (supervisory) control of flexible manufacturing systems (FMS) assures conflict-free operation and enforces production requirements such as priorities. It forms a crucial link between medium and higher-level decision making, on the one hand, and the various machine-controllers and servomechanisms on the other. In the absence of a suitable control methodology, ad hoc development is the current practice and compromised results at high cost are far too common. Here we described a model-based framework for a new, systematic approach to supervisory control. 相似文献
8.
M Maimon-Greenwald E Leibovitz N Maimon N Peled R Dagan 《Canadian Metallurgical Quarterly》1997,133(7-8):275-81, 335
During 1989-1994, there were 322 episodes of Gram-negative enteric bacteremia in 308 children. The incidence increased from 31/100,000 in children younger than 15 years of age during 1989-1991, to 50/100,000 during 1992-1994. The most common pathogens were Klebsiella, E. Coli, Salmonella and Enterobacter. 39% of episodes were nosocomial and a significant increase was recorded for each species during the last 3 years of the study. Klebsiella represented the most common pathogen causing nosocomial bacteremia, while E. coli and Salmonella were the main pathogens causing community-acquired bacteremia. In this study in southern Israel, the incidence of Gram-negative enteric bacteremia was significantly higher in Bedouin children, with the exception of bacteremia due to Salmonella, which occurred mainly in Jewish children. 相似文献
9.
Irena Brook Guy Mechrez Ran Y. Suckeveriene Roza Tchoudakov Shiran Lupo Moshe Narkis 《Polymer Composites》2014,35(4):788-794
Electrically conductive elastomeric nanocomposites containing carbon nanotubes (CNT) and polyaniline (PANI) are reported in the present investigation. The synthesis procedure included an in situ inverse emulsion polymerization of aniline doped with dodecylbenzene sulfonic acid (DBSA) in the presence of CNT and dissolved styrene‐isoprene‐styrene (SIS) block copolymer. The PANI synthesis step was carried out by applying ultrasonic energy. The dispersions obtained were processed by two methods: a recently developed precipitation‐filtration procedure, and a conventional drop‐cast procedure. The techniques developed resulted in homogeneous exfoliated PANI coated nanotubes within the elastomeric matrix. The presence of CNT/PANI in the SIS elastomeric matrix affects thermal, mechanical, and electrical properties of the nanocomposites. The formation of continuous three‐dimensional CNT/PANI networks prepared via the precipitation‐filtration method enhances the nanocomposite properties. Contrarily, the intermittent three‐dimensional network prepared by conventional drop‐cast method leads to inferior properties. Nanocomposites produced by both techniques are observed by HRSEM. The two processing techniques result in different structures, which affect the physical properties of the materials produced. A relatively low percolation threshold for both methods was determined. The Young's modulus of the SIS/CNT/PANI significantly increased in the presence of CNT. The precipitation‐filtration technique yields an improved nanocomposite product compared to the drop‐cast route. POLYM. COMPOS., 35:788–794, 2014. © 2013 Society of Plastics Engineers 相似文献
10.
We describe two patients who developed acute embolic stroke immediately after coronary catheterization for unstable angina. Transesophageal echocardiography (TEE) and spiral CT of the chest revealed protruding floating atheromas within the aortic arch. These cases of stroke immediately after coronary catheterization suggest that protruding floating atheromas of the thoracic aorta place patients at risk for stroke. TEE or CT might predict a risk of stroke in such patients. 相似文献