全文获取类型
收费全文 | 2093篇 |
免费 | 157篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 16篇 |
综合类 | 1篇 |
化学工业 | 583篇 |
金属工艺 | 33篇 |
机械仪表 | 92篇 |
建筑科学 | 76篇 |
矿业工程 | 10篇 |
能源动力 | 75篇 |
轻工业 | 570篇 |
水利工程 | 19篇 |
石油天然气 | 7篇 |
无线电 | 77篇 |
一般工业技术 | 285篇 |
冶金工业 | 38篇 |
原子能技术 | 6篇 |
自动化技术 | 364篇 |
出版年
2024年 | 10篇 |
2023年 | 26篇 |
2022年 | 86篇 |
2021年 | 145篇 |
2020年 | 79篇 |
2019年 | 95篇 |
2018年 | 107篇 |
2017年 | 100篇 |
2016年 | 102篇 |
2015年 | 94篇 |
2014年 | 114篇 |
2013年 | 258篇 |
2012年 | 166篇 |
2011年 | 190篇 |
2010年 | 158篇 |
2009年 | 117篇 |
2008年 | 90篇 |
2007年 | 50篇 |
2006年 | 53篇 |
2005年 | 34篇 |
2004年 | 25篇 |
2003年 | 20篇 |
2002年 | 25篇 |
2001年 | 9篇 |
2000年 | 11篇 |
1999年 | 13篇 |
1998年 | 17篇 |
1997年 | 12篇 |
1996年 | 4篇 |
1995年 | 10篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1975年 | 1篇 |
1966年 | 1篇 |
1965年 | 2篇 |
1964年 | 1篇 |
1963年 | 3篇 |
1938年 | 2篇 |
1926年 | 1篇 |
排序方式: 共有2252条查询结果,搜索用时 0 毫秒
11.
JANA TALASbreveOVÁ 《国际通用系统杂志》2013,42(4):645-654
This paper gives a brief summary of the linguistic fuzzy systems iheory and describes its possible application in econometric modelling. The essential feature of the used approach is a transformation of if-then rale bases into approximative deterministic behavior functions of considered economic systems. 相似文献
12.
13.
Abstract A simple geometrical model has been proposed for a citrus canopy. We assume the citrus orchard to be a lattice structure, with the trees positioned at its points and where the composite-scene reflectance is the sum of the reflectance of its individual components as weighted by their respective surfaces within a unit area. The model has been used to analyse the citrus spectral response obtained from Landsat-5 TM images for winter and summer, where the status of the orchard is different. The correlations between spectral and geometrical data show the influence of per cent crop cover, shadows and background in the composite scene reflectance. We conclude that the summer images could be more useful than the winter ones for parcel classification according to per cent crop cover. 相似文献
14.
15.
M. DELGADO-RESTITUTO A. RODRÍGUEZ-VÁZQUEZ R. LOPEZ-AHUM ADA M. LIÑAN 《International Journal of Electronics》2013,100(6):775-785
This paper presents experimental evidence of the synchronization between two monolithic chaotic oscillators. These oscillators have been fabricated using gm — C design techniques in a 2-4 μm double-poly n-well CMOS technology. The circuit realizes an oscillator from Chua's circuit family and features electrical control of the parameters in the piecewise-linear function and on-chip tuning of the oscillator natural frequencies. The area of the circuit including pads is 5 mm2 and the power dissipation is less than l-8mW for a symmetrical biasing of ±2.5V. 相似文献
16.
17.
Vinod K. Sangwan Sonal V. Rangnekar Joohoon Kang Jianan Shen Hong-Sub Lee David Lam Junhua Shen Xiaolong Liu Ana C. M. de Moraes Lidia Kuo Jie Gu Haihua Wang Mark C. Hersam 《Advanced functional materials》2021,31(52):2107385
Memristive systems present a low-power alternative to silicon-based electronics for neuromorphic and in-memory computation. 2D materials have been increasingly explored for memristive applications due to their novel biomimetic functions, ultrathin geometry for ultimate scaling limits, and potential for fabricating large-area, flexible, and printed neuromorphic devices. While the switching mechanism in memristors based on single 2D nanosheets is similar to conventional oxide memristors, the switching mechanism in nanosheet composite films is complicated by the interplay of multiple physical processes and the inaccessibility of the active area in a two-terminal vertical geometry. Here, the authors report thermally activated memristors fabricated from percolating networks of diverse solution-processed 2D semiconductors including MoS2, ReS2, WS2, and InSe. The mechanisms underlying threshold switching and negative differential resistance are elucidated by designing large-area lateral memristors that allow the direct observation of filament and dendrite formation using in situ spatially resolved optical, chemical, and thermal analyses. The high switching ratios (up to 103) that are achieved at low fields (≈4 kV cm−1) are explained by thermally assisted electrical discharge that preferentially occurs at the sharp edges of 2D nanosheets. Overall, this work establishes percolating networks of solution-processed 2D semiconductors as a platform for neuromorphic architectures. 相似文献
18.
19.
IPTV broadcast channels and video content distribution are increasingly saturating network paths. New solutions based on inter‐domain multicast protocols could contribute to the enhancement of multimedia content distribution over the Internet. The aim of this paper is to propose new capabilities for an existing inter‐domain multicast protocol, the Protocol Independent Multicast‐Sparse Mode. We describe the modified protocol and analyze its behavior using newly developed tools based on an open‐source software simulator. The resulting protocol does not require topology information, which is advantageous for easier deployment. In addition, the adopted solution avoids inherent problems with inter‐domain multicast routing, such as multiple paths and path asymmetries. 相似文献
20.
E. Moyano-Ávila L. Orozco-Barbosa F. J. Quiles 《Journal of Signal Processing Systems》2009,55(1-3):267-279
In this paper, we introduce and evaluate the parallel implementations of two video sequences decorrelation algorithms having been developed based on the non-alternating three-dimensional wavelet transform (3D-WT) and the temporal-window method. The proposed algorithms have been proven to outperform the classic 3D-WT algorithm in terms of a better coding efficiency and lower computational requirements while enabling a lossless coding and a top-quality reconstruction: the two most highly relevant features to medical imaging applications. The parallel implementations of the algorithms are developed and tested on a shared memory system, a SGI Origin 3800 supercomputer, making use of a message-passing paradigm. We evaluate and analyze the performance of the implementations in terms of the response time and speed-up factor by varying the number of processors and various video coding parameters. The key point enabling the development of highly efficient implementations rely on a workload distribution strategy supplemented by the use of parallel I/O primitives, for better exploiting the inherent features of the application and computing platform. Two sets of I/O primitives are tested and evaluated: the ones provided by the C compiler and the ones belonging to the MPI/IO library. 相似文献