全文获取类型
收费全文 | 1431篇 |
免费 | 35篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 14篇 |
综合类 | 1篇 |
化学工业 | 188篇 |
金属工艺 | 10篇 |
机械仪表 | 27篇 |
建筑科学 | 46篇 |
矿业工程 | 4篇 |
能源动力 | 31篇 |
轻工业 | 87篇 |
水利工程 | 14篇 |
石油天然气 | 2篇 |
无线电 | 237篇 |
一般工业技术 | 193篇 |
冶金工业 | 395篇 |
原子能技术 | 21篇 |
自动化技术 | 197篇 |
出版年
2021年 | 20篇 |
2020年 | 9篇 |
2019年 | 17篇 |
2018年 | 14篇 |
2017年 | 20篇 |
2016年 | 20篇 |
2015年 | 9篇 |
2014年 | 15篇 |
2013年 | 45篇 |
2012年 | 49篇 |
2011年 | 60篇 |
2010年 | 49篇 |
2009年 | 61篇 |
2008年 | 55篇 |
2007年 | 55篇 |
2006年 | 52篇 |
2005年 | 52篇 |
2004年 | 37篇 |
2003年 | 31篇 |
2002年 | 33篇 |
2001年 | 25篇 |
2000年 | 33篇 |
1999年 | 36篇 |
1998年 | 100篇 |
1997年 | 75篇 |
1996年 | 45篇 |
1995年 | 44篇 |
1994年 | 32篇 |
1993年 | 40篇 |
1992年 | 18篇 |
1991年 | 15篇 |
1990年 | 18篇 |
1989年 | 22篇 |
1988年 | 9篇 |
1987年 | 19篇 |
1986年 | 8篇 |
1985年 | 24篇 |
1984年 | 7篇 |
1983年 | 17篇 |
1982年 | 6篇 |
1981年 | 18篇 |
1980年 | 11篇 |
1979年 | 10篇 |
1978年 | 14篇 |
1977年 | 21篇 |
1976年 | 24篇 |
1975年 | 8篇 |
1973年 | 8篇 |
1971年 | 7篇 |
1970年 | 5篇 |
排序方式: 共有1467条查询结果,搜索用时 203 毫秒
51.
Inpainting has been continuously studied in the field of computer
vision. As artificial intelligence technology developed, deep learning technology
was introduced in inpainting research, helping to improve performance. Currently,
the input target of an inpainting algorithm using deep learning has been studied
from a single image to a video. However, deep learning-based inpainting technology for panoramic images has not been actively studied. We propose a 360-degree
panoramic image inpainting method using generative adversarial networks
(GANs). The proposed network inputs a 360-degree equirectangular format
panoramic image converts it into a cube map format, which has relatively little
distortion and uses it as a training network. Since the cube map format is used,
the correlation of the six sides of the cube map should be considered. Therefore,
all faces of the cube map are used as input for the whole discriminative network,
and each face of the cube map is used as input for the slice discriminative network
to determine the authenticity of the generated image. The proposed network performed qualitatively better than existing single-image inpainting algorithms and
baseline algorithms. 相似文献
52.
53.
In civil and mining operations that involve ground excavation and support, the loads are distributed between the ground and support depending on their relative stiffness. This paper presents the development of conceptual single-degree-of-freedom models, which are used to derive equations for estimating displacements and stresses for ground-support interaction problems encountered in pillars in room-andpillar mining(natural support system), and liners for circular vertical shafts(artificial support systems).For pillar assessment, mine-pillar interaction curves can be constructed using a double spring analogy.Additionally, the effectiveness of different support systems can be evaluated depending on their effect upon the mine-pillar system. For shaft design, an initial estimation of the required lining strength and thickness can be readily made based on a double ring analogue. For both problems, the results from the proposed approach compare well with those obtained by finite element numerical simulations. 相似文献
54.
I.P.L. Coleman J.A. Blair M.E. Hilburn 《The International journal of environmental studies》2013,70(3-4):187-191
The effect of a number of dietary and synthetic chelating agents on the intestinal absorption of lead has been examined using the everted sac preparation and the tracer isotope 203Pb. All the agents examined increased lead transport into the serosal compartment. An explanation of the way in which these agents modify the model to describe lead transport is proposed. 相似文献
55.
David W. Niles Xiaonan Li David Albin Doug Rose Timothy Gessert Peter Sheldon 《Progress in Photovoltaics: Research and Applications》1996,4(3):225-229
A commonly used process for forming low-resistance contacts to thin-film p-type CdTe involves the formation of a Te layer by etching the CdTe film in a concentrated mixture of nitric and phosphoric acids. The authors compare evaporated Te back contacts with ‘control’ back contacts formed by the usual etching process, and demonstrate that evaporating Te onto a CdTe thin film is a viable process for forming a low-resistance contact. The best efficiency achieved for a CdTe solar cell made with an evaporated Te back contact is 12.1%, whereas the efficiency of the device made with the control back contact was 11.9%. The evaporation process offers numerous advantages over acid etching, most notably vacuum compatibility amenable to large-scale production of CdTe solar cell modules. 相似文献
56.
Scaling the Aspect Ratio of Nanoscale Closely Packed Silicon Vias by MacEtch: Kinetics of Carrier Generation and Mass Transport
下载免费PDF全文
![点击此处可从《Advanced functional materials》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Jeong Dong Kim Parsian K. Mohseni Karthik Balasundaram Srikanth Ranganathan Jayavel Pachamuthu James J. Coleman Xiuling Li 《Advanced functional materials》2017,27(12)
Metal‐assisted chemical etching (MacEtch) has shown tremendous success as an anisotropic wet etching method to produce ultrahigh aspect ratio semiconductor nanowire arrays, where a metal mesh pattern serves as the catalyst. However, producing vertical via arrays using MacEtch, which requires a pattern of discrete metal disks as the catalyst, has often been challenging because of the detouring of individual catalyst disks off the vertical path while descending, especially at submicron scales. Here, the realization of ordered, vertical, and high aspect ratio silicon via arrays by MacEtch is reported, with diameters scaled from 900 all the way down to sub‐100 nm. Systematic variation of the diameter and pitch of the metal catalyst pattern and the etching solution composition allows the extraction of a physical model that, for the first time, clearly reveals the roles of the two fundamental kinetic mechanisms in MacEtch, carrier generation and mass transport. Ordered submicron diameter silicon via arrays with record aspect ratio are produced, which can directly impact the through‐silicon‐via technology, high density storage, photonic crystal membrane, and other related applications. 相似文献
57.
Fernandes A.L. Raginsky M. Coleman T.P. 《Signal Processing, IEEE Transactions on》2009,57(5):1731-1744
We propose a scheme for rate-constrained distributed nonparametric regression using a wireless sensor network. The scheme is universal across a wide range of sensor noise models, including unbounded and nonadditive noise; it has low complexity, requiring simple operations such as uniform scalar quantization with dither and message passing between neighboring nodes in the network, and attains minimax optimality for regression functions in common smoothness classes. We present theoretical results on the tradeoff between the compression rate, communication complexity of encoding, and the MSE and demonstrate empirical performance of the scheme using simulations. 相似文献
58.
Scouring at Bed Sills as a Response to Flash Floods 总被引:1,自引:0,他引:1
Matteo Tregnaghi Andrea Marion Stephen Coleman 《Canadian Metallurgical Quarterly》2009,135(6):466-475
The temporal development of clear-water local scour depth at bed sills in uniform gravel beds is considered. Experiments are presented on the development of scour holes under unsteady hydraulic conditions, with the triangular-shaped hydrographs tested being of different durations and different rates of flow variation. Based on the experimental results and a theoretical framework, a method is given for the definition and prediction of the scouring process under unsteady flows in terms of a dimensionless temporal parameter. A “flash flood” is here defined as an event for which the scour doesn’t attain its potential magnitude, i.e., the equilibrium value for the peak hydrograph flow rate. This flood nature is dependent on both the characteristics of the flood event itself and the characteristics of the stream. A quantitative measure of what constitutes a flash flood is given in terms of the identified temporal parameter. Results show that the ratio between the final scour depth and the potential scour depth at a bed sill for a given hydrograph can be estimated as a function of the identified temporal parameter. 相似文献
59.
In a grain-boundary-engineered (GBE) microstructure, Σ9 boundaries are the second most abundant boundary type. This article
presents data showing that, in GBE copper, most Σ9s were special. Σ9 boundaries are also a geometrically necessary component
of a GBE microstructure. It is suggested that there are competing requirements for Σ9s; during iterative GBE processing, they
are required to be mobile, whereas afterward, it is desirable that they are special boundaries. 相似文献
60.