全文获取类型
收费全文 | 1668篇 |
免费 | 31篇 |
国内免费 | 5篇 |
专业分类
电工技术 | 69篇 |
化学工业 | 313篇 |
金属工艺 | 60篇 |
机械仪表 | 37篇 |
建筑科学 | 43篇 |
能源动力 | 47篇 |
轻工业 | 137篇 |
水利工程 | 8篇 |
无线电 | 176篇 |
一般工业技术 | 205篇 |
冶金工业 | 441篇 |
原子能技术 | 54篇 |
自动化技术 | 114篇 |
出版年
2023年 | 8篇 |
2022年 | 21篇 |
2021年 | 29篇 |
2020年 | 14篇 |
2019年 | 14篇 |
2018年 | 16篇 |
2017年 | 29篇 |
2016年 | 23篇 |
2015年 | 19篇 |
2014年 | 26篇 |
2013年 | 59篇 |
2012年 | 50篇 |
2011年 | 72篇 |
2010年 | 47篇 |
2009年 | 65篇 |
2008年 | 74篇 |
2007年 | 55篇 |
2006年 | 42篇 |
2005年 | 56篇 |
2004年 | 36篇 |
2003年 | 46篇 |
2002年 | 43篇 |
2001年 | 34篇 |
2000年 | 47篇 |
1999年 | 42篇 |
1998年 | 170篇 |
1997年 | 109篇 |
1996年 | 64篇 |
1995年 | 54篇 |
1994年 | 47篇 |
1993年 | 52篇 |
1992年 | 17篇 |
1991年 | 23篇 |
1990年 | 12篇 |
1989年 | 13篇 |
1988年 | 16篇 |
1987年 | 9篇 |
1986年 | 16篇 |
1985年 | 9篇 |
1984年 | 9篇 |
1983年 | 10篇 |
1982年 | 10篇 |
1981年 | 6篇 |
1980年 | 11篇 |
1979年 | 10篇 |
1978年 | 6篇 |
1977年 | 10篇 |
1976年 | 22篇 |
1975年 | 7篇 |
1973年 | 7篇 |
排序方式: 共有1704条查询结果,搜索用时 16 毫秒
101.
Power systems have become very large, and in addition the forthcoming open electricity market will make power system operation more complex. Therefore, power system operation must become more efficient and flexible. Very fast power system simulation is a means of achieving more sophisticated power system on‐line monitoring and control, and parallel computing is a key technology for very fast power system simulation. This paper proposes an efficient and fast parallel network calculation algorithm that will contribute to the development of fast power system simulation programs. Numerical examples show that the proposed method using six processors is about 4.0 times as fast as the usual serial algorithm when applied to a large‐scale radial power system and about 3.2 times as fast when applied to a large‐scale loop power system. © 2001 Scripta Technica, Electr Eng Jpn, 135(3): 26–36, 2001 相似文献
102.
Syuji Fujii Yukihiro Nishimura Atsushi Aichi Soichiro Matsuzawa Yoshinobu Nakamura Kensuke Akamatsu Hidemi Nawafune 《Synthetic Metals》2010,160(13-14):1433-1437
Polyaniline–silver nanocomposites were synthesized in the form of colloidal particles by the facile one-step aqueous chemical oxidative dispersion polymerization of aniline using silver nitrate as an oxidant and poly(vinyl alcohol) as a colloidal stabilizer. Aniline monomer was oxidized by silver ions, yielding polyaniline and elemental Ag simultaneously. The synthesized nanocomposite particles were colloidally stable over 2 years and transmission electron microscopy studies indicated the production of spherical, plate and rod-shaped polyaniline–silver nanocomposite particles with a silver core–polyaniline shell morphology. The conductivity of a pressed pellet of the nanocomposite particles using the conventional four-point probe technique was 1.4 × 10?2 S/cm at 25 °C. The nanocomposite particles behaved as a ‘colored’ particulate emulsifier for the stabilization of transparent oil-in-water emulsions. 相似文献
103.
104.
Yukao Tanaka Hidetoshi Nishigaito Hiroo Konishi Masashi Nishimura 《Electrical Engineering in Japan》2001,136(3):49-57
An advanced real‐time power system simulator consisting of a conventional real‐time analog simulator and a real‐time digital simulator has been developed. EMTP simulations were carried out to verify the advanced power system simulator concept and to evaluate the effects of various parameters. A prototype of the advanced power system simulator using the Bergeron method was tested. The test results confirmed the feasibility of the real‐time power system simulator. © 2001 Scripta Technica, Electr Eng Jpn, 136(3): 49–57, 2001 相似文献
105.
Nishimura S. Inoue H. Matsuoka H. Yokota T. 《IEEE journal of selected topics in quantum electronics》1999,5(2):360-367
Optical interconnection between the nodes of the RWC-1 massively parallel computer has been implemented. A one-node testbed system and an eight-node parallel processing system have been produced to demonstrate large-throughput small-skew low-latency and highly reliable optical internode connection. Each node was interconnected through dc-coupled 24-bit synchronized parallel optical interconnection at 100 MHz using 50-m-long single-mode ribboned fibers. The skew in a 24-bit data signal was suppressed to within 650 to -380 ps, and the OE/EO conversion delay time was 15.2 ns. We ran a parallel-processing program on the eight-node system as an evaluation, and the 50-m-long optically interconnected system performed as well as a 10-m-long electrically interconnected system. This clearly shows that optical interconnection will overcome the communication bottleneck in multinode computer systems 相似文献
106.
Matsuda S. Ogi H. Nishimura K. Okataku Y. Tamura S. 《Industrial Electronics, IEEE Transactions on》1990,37(3):236-240
A case study of the application of a distributed control scheme to a power system control is presented. In addition, an investigation has been conducted into voltage control. Combined injection of VAr-compensating devices controlled by distributed expert systems has been proposed as a measure to maintain voltage stability in a power system under heavy loading conditions. A simulation study has been carried out by using five workstations that represent a power system and four VAr-compensating devices. The results demonstrate the effectiveness of the proposed system for voltage recovery 相似文献
107.
In this paper, the optimization of a generic function of a lipstick manufacturing process is discussed. Traditionally, the quality of lipsticks has been measured by objective quality characteristics such as appearance. Sensory tests, which are not recommended in quality engineering, had been used to evaluate such quality characteristics. That is because these quality characteristics are not stable due to the changes of environmental conditions such as between-lot variability and seasonal variation. When such quality problems occurred, manufacturing conditions were adjusted from time to time, which is known as fire fighting or 'mole beating' in Japanese. Among those objective quality characteristics, the ones such as scratches, colour uniformity or breaking during usage are manufacturing related. As a generic function, the stress/strain relationship was investigated and the results showed that the relationship has satisfied Hook's Law with a good improvement. 相似文献
108.
M Satoh N Nishimura Y Kanayama A Naganuma T Suzuki C Tohyama 《Canadian Metallurgical Quarterly》1997,283(3):1529-1533
To elucidate a protective role of metallothionein (MT) in the manifestation of inorganic mercury toxicity, we studied the susceptibility of MT-null mice to the renal toxicity of mercuric chloride. Because the MT-null (J) mice are a genetic background of 129/Sv strain, the 129/Sv mice were used as wild-type controls. Nine-week-old male MT-null (J) and 129/Sv mice were given subcutaneous injections of mercuric chloride at doses of 10 to 40 micromol/kg. The basal MT level in the kidney of MT-null (J) mice was undetectable (<0.2 microg/g of tissue) and approximately 2.5 microg/g of tissue in 129/Sv mice. The sensitivity to the renal toxicity of mercuric chloride was markedly enhanced in the MT-null (J) mice compared with the 129/Sv mice. The renal mercury level was similar for the MT-null (J) and 129/Sv mice at 4 hr after the injection of mercuric chloride (20 micromol/kg) but became significantly lower in MT-null (J) mice than in 129/Sv mice at 24 and 72 hr. Based on the present results, we conclude that MT is an important protective factor against the renal toxicity caused by inorganic mercury and that it may play a major role in the retention of mercury in the kidney. 相似文献
109.
Isokawa T. Matsui N. Nishimura H. Peper F. 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2002,32(4):497-504
In nonstationary environments, it is difficult to apply traditional genetic algorithms (GAs) because they use strong selection pressure and lose the diversity of individuals rapidly. We propose a GA with neutral variation that can track environmental changes. The idea of this GA is inspired by Kimura's neutral theory (1983). The scheme of this GA allows neutral characters, which do not directly affect the fitness with respect to environments, thus increasing the diversity of individuals. In order to demonstrate the properties of this GA, we apply it to a permutation problem called the ladder-network, of which the imposed alignment on the output changes regularly. We show that the GA with neutral variation can adapt better to environmental changes than a traditional GA. 相似文献
110.
Kambara K. Nishimoto H. Nishimura T. Ohgane T. Ogawa Y. 《Selected Areas in Communications, IEEE Journal on》2008,26(2):359-365
Frequency domain equalization (FDE) has been studied for reducing inter-symbol interference (ISI) caused by frequency selective fading in single carrier systems. When a high-mobility terminal exists in the system, the channel state may change within a DFT block. Then, the ISI reduction performance of FDE degrades since cyclicity of the channel matrix is lost. We propose to divide a received data block into multiple subblocks to decrease the channel transition within the DFT block in fast fading environments. Also, to satisfy periodicity of the received signal in each subblock, we introduce a pseudo cyclic prefix technique. The results of numerical analysis show that the proposed method can effectively decrease the error floor in fast fading environments. 相似文献