全文获取类型
收费全文 | 442篇 |
免费 | 30篇 |
专业分类
电工技术 | 2篇 |
化学工业 | 138篇 |
金属工艺 | 1篇 |
机械仪表 | 16篇 |
建筑科学 | 14篇 |
能源动力 | 22篇 |
轻工业 | 37篇 |
水利工程 | 1篇 |
无线电 | 47篇 |
一般工业技术 | 43篇 |
冶金工业 | 49篇 |
自动化技术 | 102篇 |
出版年
2023年 | 7篇 |
2022年 | 7篇 |
2021年 | 41篇 |
2020年 | 16篇 |
2019年 | 8篇 |
2018年 | 14篇 |
2017年 | 18篇 |
2016年 | 22篇 |
2015年 | 19篇 |
2014年 | 26篇 |
2013年 | 29篇 |
2012年 | 23篇 |
2011年 | 22篇 |
2010年 | 18篇 |
2009年 | 27篇 |
2008年 | 13篇 |
2007年 | 13篇 |
2006年 | 14篇 |
2005年 | 21篇 |
2004年 | 15篇 |
2003年 | 13篇 |
2002年 | 8篇 |
2001年 | 10篇 |
2000年 | 7篇 |
1999年 | 5篇 |
1998年 | 5篇 |
1997年 | 6篇 |
1996年 | 11篇 |
1995年 | 7篇 |
1994年 | 5篇 |
1993年 | 5篇 |
1992年 | 4篇 |
1991年 | 1篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1976年 | 3篇 |
排序方式: 共有472条查询结果,搜索用时 14 毫秒
11.
Michela Rossi 《Nexus Network Journal》2006,8(1):1-2
Letter from the Editor
Letter from the editor 相似文献12.
Michela Mortara Giuseppe Patané Michela Spagnuolo Bianca Falcidieno Jarek Rossignac 《Algorithmica》2003,38(1):227-248
Tools for the automatic decomposition of a surface into shape
features will facilitate the editing, matching, texturing,
morphing, compression and simplification of three-dimensional shapes. Different
features, such as flats, limbs, tips, pits and various blending
shapes that transition between them, may be characterized in terms
of local curvature and other differential properties of the
surface or in terms of a global skeletal organization of the
volume it encloses. Unfortunately, both solutions are extremely
sensitive to small perturbations in surface smoothness and to
quantization effects when they operate on triangulated surfaces.
Thus, we propose a multi-resolution approach, which not only
estimates the curvature of a vertex over neighborhoods of variable
size, but also takes into account the topology of the surface in
that neighborhood. Our approach is based on blowing a spherical
bubble at each vertex and studying how the intersection of that
bubble with the surface evolves. We describe an efficient approach
for computing these characteristics for a sampled set of bubble
radii and for using them to identify features, based on easily
formulated filters, that may capture the needs of a particular
application. 相似文献
13.
Its more refined congestion control mechanisms, also based on the estimation of round trip delays, allow TCP Vegas to outperform the more widespread TCP Reno congestion control, based only on the packet loss detection, in a number of network environments. However, these mechanisms make TCP Vegas less aggressive with respect to TCP Reno; thereby TCP Vegas sources show high weakness in taking the available bandwidth when competing with other TCP Reno sources. This is a major reason that hinders the spread of TCP Vegas among Internet users. In this work, after a preliminary analytic study about the limits of TCP Vegas in mixed network environments, we describe a new adaptive mechanism for TCP Vegas, called TCP NewVegas, designed in order to improve its performance even in heterogeneous network scenarios. The large number of simulations, presented in this paper, show that TCP NewVegas guarantees good performance even in mixed network environments, without canceling the desirable features (e.g. fairness) that TCP Vegas exhibits in homogeneous environments. 相似文献
14.
15.
16.
La Russa Mauro F. Ruffolo Silvestro A. de Buergo Mónica Álvarez Ricca Michela Belfiore Cristina M. Pezzino Antonino Crisci Gino M. 《Bulletin of Engineering Geology and the Environment》2017,76(1):115-124
Bulletin of Engineering Geology and the Environment - Salt crystallization is a strong weathering agent in porous building materials. The crystallization pressure exerted by salt crystals, growing... 相似文献
17.
18.
19.
This study investigates the structural, morphological, thermal, and mechanical properties of type A gelatin/montmorillonite (MMT) films as a function of MMT concentration. The variations of the X‐ray diffraction pattern suggest that the structure of the nanocomposites turns from intercalated to exfoliated on increasing clay loading up to 20 wt %. Simultaneously, gelatin interaction with clay negative sheets during gelling provokes a reduction of the triple helix content of the composite films, in agreement with the reduction of the relative intensity of the 1.1 nm diffraction reflection of gelatin and of the values of denaturation enthalpy. On the other hand, the increase of the denaturation and decomposition temperatures, the significant rise of the Young's modulus, as well as the swelling decrease observed as clay content increases, demonstrate a relevant stabilizing effect of MMT on gelatin. The reinforcement action of MMT allows to utilize a relatively low concentration of the crosslinking agent genipin to further stabilize the films. The synergic action of clay and genipin prevents dissolution of the nanocomposites in aqueous solution and enhances their mechanical properties. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40301. 相似文献
20.
Filippo Piccinini Michela Pierini Enrico Lucarelli Alessandro Bevilacqua 《Journal of materials science. Materials in medicine》2014,25(10):2395-2410
The analysis of cell confluence and proliferation is essential to design biomaterials and scaffolds to use as bone substitutes in clinical applications. Accordingly, several approaches have been proposed in the literature to estimate the area of the scaffold covered by cells. Nevertheless, most of the approaches rely on sophisticated equipment not employed for routine analyses, while the rest of them usually do not provide significant statistics about the cell distribution. This research aims at studying confluence and proliferation of mesenchymal stromal cells (MSC) adherent on OSPROLIFE®, a commercial biomaterial in the form of granules. In particular, we propose a Computer Vision approach that can routinely be employed to monitor the surface of the single granules covered by cells because only a standard widefield fluorescent microscope is required. In order to acquire significant statistics data, we analyse wide-area images built by using MicroMos v2.0, an updated version of a previously published software specific for stitching brightfield and phase-contrast images manually acquired via a widefield microscope. In particular, MicroMos v2.0 permits to build accurate “mosaics” of fluorescent images, after correcting vignetting and photo-bleaching effects, providing a consistent representation of a sample region containing numerous granules. Then, our method allows to make automatically a statistically significant estimate of the percentage of the area of the single granules covered by cells. Finally, by analysing hundreds of granules at different time intervals we also obtained reliable data regarding cell proliferation, confirming that not only MSC adhere onto the OSPROLIFE® granules, but even proliferate over time. 相似文献