全文获取类型
收费全文 | 439篇 |
免费 | 36篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 12篇 |
综合类 | 3篇 |
化学工业 | 141篇 |
金属工艺 | 9篇 |
机械仪表 | 5篇 |
建筑科学 | 18篇 |
矿业工程 | 1篇 |
能源动力 | 22篇 |
轻工业 | 57篇 |
水利工程 | 1篇 |
无线电 | 39篇 |
一般工业技术 | 93篇 |
冶金工业 | 11篇 |
自动化技术 | 64篇 |
出版年
2023年 | 27篇 |
2022年 | 29篇 |
2021年 | 44篇 |
2020年 | 29篇 |
2019年 | 38篇 |
2018年 | 19篇 |
2017年 | 17篇 |
2016年 | 26篇 |
2015年 | 12篇 |
2014年 | 14篇 |
2013年 | 22篇 |
2012年 | 22篇 |
2011年 | 21篇 |
2010年 | 13篇 |
2009年 | 20篇 |
2008年 | 12篇 |
2007年 | 8篇 |
2006年 | 3篇 |
2005年 | 6篇 |
2004年 | 5篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1997年 | 8篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1981年 | 2篇 |
1980年 | 6篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1974年 | 2篇 |
1928年 | 2篇 |
1927年 | 5篇 |
1926年 | 3篇 |
1924年 | 2篇 |
1923年 | 1篇 |
1922年 | 4篇 |
1921年 | 2篇 |
1920年 | 4篇 |
1918年 | 2篇 |
1916年 | 1篇 |
1915年 | 1篇 |
1913年 | 1篇 |
1912年 | 3篇 |
1911年 | 1篇 |
1910年 | 1篇 |
1909年 | 3篇 |
1907年 | 2篇 |
排序方式: 共有476条查询结果,搜索用时 312 毫秒
21.
22.
Girish Chowdhary Maximilian Mühlegg Eric Johnson 《International journal of control》2013,86(8):1583-1603
In model reference adaptive control (MRAC) the modelling uncertainty is often assumed to be parameterised with time-invariant unknown ideal parameters. The convergence of parameters of the adaptive element to these ideal parameters is beneficial, as it guarantees exponential stability, and makes an online learned model of the system available. Most MRAC methods, however, require persistent excitation of the states to guarantee that the adaptive parameters converge to the ideal values. Enforcing PE may be resource intensive and often infeasible in practice. This paper presents theoretical analysis and illustrative examples of an adaptive control method that leverages the increasing ability to record and process data online by using specifically selected and online recorded data concurrently with instantaneous data for adaptation. It is shown that when the system uncertainty can be modelled as a combination of known nonlinear bases, simultaneous exponential tracking and parameter error convergence can be guaranteed if the system states are exciting over finite intervals such that rich data can be recorded online; PE is not required. Furthermore, the rate of convergence is directly proportional to the minimum singular value of the matrix containing online recorded data. Consequently, an online algorithm to record and forget data is presented and its effects on the resulting switched closed-loop dynamics are analysed. It is also shown that when radial basis function neural networks (NNs) are used as adaptive elements, the method guarantees exponential convergence of the NN parameters to a compact neighbourhood of their ideal values without requiring PE. Flight test results on a fixed-wing unmanned aerial vehicle demonstrate the effectiveness of the method. 相似文献
23.
Bernhard Ostrick Maximilian Fleischer Hans Meixner 《Journal of the American Ceramic Society》1997,80(8):2153-2156
Simultaneous Hall and conductivity measurements were performed in situ between 650° and 1050°C on n-type semiconducting BaSnO3 ceramics. The variation of the Hall mobility and the Hall carrier density as a function of oxygen partial pressure between 102 and 105 Pa and of temperature was investigated. At temperatures below 900°C the conductivity exhibits a dependence on temperature and oxygen partial pressure which is mainly determined by variations of the Hall mobility. Above 900°C most of the significant dependence is due to a variation in carrier density. Furthermore, a simple defect model assuming doubly ionized oxygen vacancies and acceptor impurities is discussed for BaSnO3 . 相似文献
24.
25.
Nicolas Vogel Mathieu Jung Noelia L. Bocchio Markus Retsch Maximilian Kreiter Ingo Köper 《Small (Weinheim an der Bergstrasse, Germany)》2010,6(1):104-109
Nanoparticle arrays created by nanosphere lithography are widely used in sensing applications since their localized surface plasmon resonances are extremely sensitive to changes in the local dielectric environment. A major drawback for any biologically oriented sensing application of conventionally produced particle arrays is the lack of stability of the nanoparticles in aqueous media and buffer solutions. Here, a robust and reusable nanoscale sensing platform based on localized surface plasmon resonances of gold nanoparticles embedded in a silicon dioxide matrix is presented. The architecture exhibits extremely high stability in aqueous environments and can be regenerated several times by simple mechanical cleaning of the surface. The platforms surface is ultraflat by design, thus making it an ideal substrate for any bio‐oriented sensing application. 相似文献
26.
Konrad Amberger 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1916,31(10):297-308
Ohne ZusammenfassungMitteilung aus der Kgl. Untersuchungsanstalt Erlangen. 相似文献
27.
28.
29.
Vanesa Palau Bramasta Nugraha David Benito Julio Pascual Maximilian Y. Emmert Simon P. Hoerstrup Marta Riera Maria Jos Soler 《International journal of molecular sciences》2021,22(11)
ADAM17 is a disintegrin and metalloproteinase capable of cleaving the ectodomains of a diverse variety of molecules including TNF-α, TGF-α, L-selectin, and ACE2. We have previously demonstrated that renal ADAM17 is upregulated in diabetic mice. The role of endothelial (eAdam17) and proximal tubular (tAdam17) Adam17 deletion in renal histology, modulation of the renin angiotensin system (RAS), renal inflammation, and fibrosis was studied in a mouse model of type 1 Diabetes Mellitus. Moreover, the effect of Adam17 deletion in an in vitro 3D cell culture from human proximal tubular cells under high glucose conditions was evaluated. eAdam17 deletion attenuates renal fibrosis and inflammation, whereas tAdam17 deletion decreases podocyte loss, attenuates the RAS, and decreases macrophage infiltration, α-SMA and collagen accumulation. The 3D in vitro cell culture reinforced the findings obtained in tAdam17KO mice with decreased fibrosis in the Adam17 knockout spheroids. In conclusion, Adam17 deletion either in the endothelial or the tubular cells mitigates kidney injury in the diabetic mice by targeting different pathways. The manipulation of Adam17 should be considered as a therapeutic strategy for treating DN. 相似文献
30.
The absorption, magnetic circular dichroism and luminescence spectra of monomeric pseudo trigonal planar (η5-Me3SiC5H4)3PrIII (Cp′Pr) have been measured at room and at low temperatures. Applying the selection rules for molecular D3h symmetry, a truncated crystal field (CF) splitting pattern (which comprises essentially excited Γ4 and Γ6 states) could be derived. The parameters of an empirical Hamiltonian were fitted to the energies of 24 levels to give an r.m.s. deviation of 21.4 cm−1. On the basis of the CF parameters obtained, the CF strength of one Cp ligand was estimated. 相似文献