全文获取类型
收费全文 | 1395篇 |
免费 | 81篇 |
国内免费 | 19篇 |
专业分类
电工技术 | 20篇 |
综合类 | 4篇 |
化学工业 | 347篇 |
金属工艺 | 35篇 |
机械仪表 | 40篇 |
建筑科学 | 29篇 |
能源动力 | 52篇 |
轻工业 | 55篇 |
水利工程 | 1篇 |
无线电 | 280篇 |
一般工业技术 | 254篇 |
冶金工业 | 103篇 |
原子能技术 | 4篇 |
自动化技术 | 271篇 |
出版年
2023年 | 12篇 |
2022年 | 22篇 |
2021年 | 37篇 |
2020年 | 17篇 |
2019年 | 24篇 |
2018年 | 29篇 |
2017年 | 36篇 |
2016年 | 45篇 |
2015年 | 38篇 |
2014年 | 81篇 |
2013年 | 121篇 |
2012年 | 73篇 |
2011年 | 86篇 |
2010年 | 71篇 |
2009年 | 93篇 |
2008年 | 78篇 |
2007年 | 79篇 |
2006年 | 66篇 |
2005年 | 49篇 |
2004年 | 44篇 |
2003年 | 40篇 |
2002年 | 39篇 |
2001年 | 28篇 |
2000年 | 26篇 |
1999年 | 18篇 |
1998年 | 48篇 |
1997年 | 31篇 |
1996年 | 19篇 |
1995年 | 19篇 |
1994年 | 18篇 |
1993年 | 13篇 |
1992年 | 5篇 |
1991年 | 6篇 |
1990年 | 3篇 |
1989年 | 10篇 |
1988年 | 7篇 |
1986年 | 5篇 |
1985年 | 9篇 |
1984年 | 9篇 |
1983年 | 2篇 |
1982年 | 6篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1979年 | 4篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1970年 | 2篇 |
排序方式: 共有1495条查询结果,搜索用时 31 毫秒
41.
We use the graphical processing unit (GPU) to accelerate the tensor contractions, which is the most time consuming operations in the variational method based on the plaquette renormalized states. Using a frustrated Heisenberg J1–J2 model on a square lattice as an example, we implement the algorithm based on the compute unified device architecture (CUDA). For a single plaquette contraction with the bond dimensions C = 3 of each rank of the tensor, results are obtained 25 times faster on GPU than on a current CPU core. This makes it possible to simulate systems with the size 8 × 8 and larger, which are extremely time consuming on a single CPU. This technology successfully relieves the computing time dependence with C, while in the CPU serial computation, the total required time scales both with C and the system size. 相似文献
42.
Tzuu-Hseng Li Shun-Hung Tsai Jia-Zhen Lee Ming-Ying Hsiao Chan-Hong Chao 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2008,38(2):510-527
The main theme of this paper is to present robust fuzzy controllers for a class of discrete fuzzy bilinear systems. First, the parallel distributed compensation method is utilized to design a fuzzy controller, which ensures the robust asymptotic stability of the closed-loop system and guarantees an H(infinity) norm-bound constraint on disturbance attenuation for all admissible uncertainties. Second, based on the Schur complement and some variable transformations, the stability conditions of the overall fuzzy control system are formulated by linear matrix inequalities. Finally, the validity and applicability of the proposed schemes are demonstrated by a numerical simulation and the Van de Vusse example. 相似文献
43.
Versatile Transcoding Proxy for Internet Content Adaptation 总被引:2,自引:0,他引:2
44.
Matthew Arnold Michael Hsiao Ulrich Kremer Barbara G. Ryder 《International journal of parallel programming》2001,29(2):111-137
The frequent occurrence of implicitly thrown exceptions poses one of the challenges present in a Java compiler. Not only do these implicitly thrown exceptions directly affect the performance by requiring explicit checks, they also indirectly impact the performance by restricting code movement in order to satisfy the precise exception model in Java. In particular, instruction scheduling is one transformation that is restricted by implicitly thrown exceptions due to the heavy reliance on reordering instructions to exploit maximum hardware performance. The goal of this study is two-fold: first, investigate the degree to which implicitly thrown exceptions in Java hinder instruction scheduling, and second, find new techniques for allowing more efficient execution of Java programs containing implicitly thrown exceptions. Experimental results show that with aggressive scheduling techniques, such as superblock scheduling, the negative performance impact can be greatly reduced. 相似文献
45.
The Journal of Supercomputing - Rapid advances in interconnection networks in multiprocessors are closing the gap between computation and communication. Given this trend, how can we utilize fast... 相似文献
46.
47.
We describe the parallelization of a first-order logic theorem prover that is based on the hyper-linking proof procedure (HLPP). Four parallel schemes – process level, clause level, literal level, and flow level – are developed for two types of sequential implementation of HLPP: list based and network based. The motivation for developing each parallel scheme is presented, and the architecture and implementation details of each scheme are described. Issues about parallel processing, such as serialization and synchronization, load balancing, and access conflicts, are examined. Speedups over sequential implementations are attained, and timing results for benchmark problems are provided. 相似文献
48.
49.
A lot of older adults try to learn to use computers and might use different ways to perform a computer task compared to younger people. Fifteen healthy young and 15 healthy older adults participated in this study and all performed a series of mouse tasks. A three dimensional motion capture system and electromyographic analysis were used to obtain kinematic and kinetic data during performing the computer tasks. Three-way analysis of variance with repeated measures on task and time factors was used to analyze all dependent measurements. Older adults had higher RMS of forearm muscles compared to the young adults. The RMS of the finger extensor was highest when performing a dragging task. Compared with young adults, the older adults had greater cranial-cervical angle and neck flexion, but smaller head flexion, shoulder angle, elbow angle and ulnar deviation. Consequently, the older adults might have a greater risk of developing musculoskeletal disorder. 相似文献
50.
Te-Hua Fang Yu-Jen Hsiao Yee-Shin Chang Yen-Hwei Chang 《Materials Chemistry and Physics》2006,100(2-3):418-422
In this study, the photoluminescence (PL) spectra of europium-doped potassium niobate (KNbO3) crystallites prepared by a vibrating milled solid-state reaction method were studied. X-ray diffraction (XRD), scanning electron microscopy (SEM) and optical spectral analysis (luminescence excitation, emission spectra and time-resolved spectra) were used to characterize the KNbO3:Eu3+ powders. The results of the XRD revealed that the powders remained as a single orthorhombic structure at doping concentrations below 3 mol%. A second phase of EuNbO4 begins to appear at 5 mol%. The 5D0–7F1 (593 nm) and 5D0–7F2 (614 nm) emission characteristics of Eu3+ appear at a quenching concentration of above 3 mol%. The Commission Internationale d’Eclairage (CIE) chromaticity coordinates of a Eu:KNbO3 host excited at λex = 400 nm and λex = 466 nm wavelengths, both presented a red-shift when increasing the Eu3+ ion doping. The lifetime of the Eu3+ ion decreased as the doping concentration was increased from 1 to 7 mol%. 相似文献