全文获取类型
收费全文 | 431篇 |
免费 | 4篇 |
学科分类
工业技术 | 435篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 4篇 |
2020年 | 2篇 |
2017年 | 6篇 |
2016年 | 8篇 |
2015年 | 2篇 |
2014年 | 6篇 |
2013年 | 17篇 |
2012年 | 18篇 |
2011年 | 17篇 |
2010年 | 17篇 |
2009年 | 17篇 |
2008年 | 15篇 |
2007年 | 14篇 |
2006年 | 17篇 |
2005年 | 10篇 |
2004年 | 9篇 |
2003年 | 9篇 |
2002年 | 10篇 |
2001年 | 4篇 |
2000年 | 9篇 |
1999年 | 16篇 |
1998年 | 21篇 |
1997年 | 15篇 |
1996年 | 15篇 |
1995年 | 19篇 |
1994年 | 17篇 |
1993年 | 9篇 |
1992年 | 6篇 |
1991年 | 10篇 |
1990年 | 11篇 |
1989年 | 8篇 |
1988年 | 7篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 5篇 |
1984年 | 8篇 |
1983年 | 4篇 |
1982年 | 7篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1978年 | 5篇 |
1977年 | 4篇 |
1976年 | 2篇 |
1968年 | 1篇 |
1967年 | 3篇 |
1927年 | 1篇 |
1926年 | 1篇 |
排序方式: 共有435条查询结果,搜索用时 0 毫秒
51.
52.
Simultaneous measurements of space charge and external current were carried out using a PEA measurement system with an electrometer on the back of a grounding electrode in order to clarify the physical situation of a huge packet of positive space charges in LDPE films. A large number of positive charges from a semiconducting anode were accumulated at the interface between LDPE and an Al‐cathode at a mean applied field of 1.5 MV/cm and then finally disappeared. The results of simultaneous measurements showed that the external current kept a relatively high value during charge accumulation and further increased when the charges disappeared. Both the charge dynamics and the external current were restricted by addition of a low‐molecular‐weight paraffin wax, indicating that carrier transport was influenced by the microstructure of the polymer. The dynamics of the residual charges after short‐circuiting is also discussed. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 179(4): 10–17, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21256 相似文献
53.
Low Capture Switching Activity Test Generation for Reducing IR-Drop in At-Speed Scan Testing 总被引:1,自引:1,他引:0
Xiaoqing Wen Kohei Miyase Tatsuya Suzuki Seiji Kajihara Laung-Terng Wang Kewal K. Saluja Kozo Kinoshita 《Journal of Electronic Testing》2008,24(4):379-391
At-speed scan testing, based on ATPG and ATE, is indispensable to guarantee timing-related test quality in the DSM era. However,
at-speed scan testing may incur yield loss due to excessive IR-drop caused by high test (shift & capture) switching activity.
This paper discusses the mechanism of circuit malfunction due to IR-drop, and summarizes general approaches to reducing switching
activity, by which highlights the problem of current solutions, i.e. only reducing switching activity for one capture while
the widely used at-speed scan testing based on the launch-off-capture scheme uses two captures. This paper then proposes a
novel X-filling method, called double-capture (DC) X-filling, for generating test vectors with low and balanced capture switching activity for two captures. Applicable to dynamic & static
compaction in any ATPG system, DC X-filling can reduce IR-drop, and thus yield loss, without any circuit/clock modification, timing/circuit overhead, fault coverage
loss, and additional design effort.
相似文献
Xiaoqing WenEmail: |
54.
Zhi-Qiang Chen Rong-Long Wang Kozo Okazaki 《IEEJ Transactions on Electrical and Electronic Engineering》2009,4(5):663-667
Bipartite subgraph problem is an important example of a class of combinatorial optimization problems. It has many important applications in modeling matching problem, modern coding theory, communication network, and computer science. The goal of this NP-complete problem is to find a bipartite subgraph with maximum number of edges of the given graph. In this paper, for efficiently solving the problem, we propose a genetic algorithm-based approach in which the genetic operators are performed based on the condition instead of probability. The proposed algorithm is tested on a large number of instances, and the experimental results show that the proposed algorithm is superior to its competitors. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
55.
Rapid manufacturing of metal components by laser forming 总被引:11,自引:0,他引:11
Edson Costa Santos Masanari Shiomi Kozo Osakada Tahar Laoui 《International Journal of Machine Tools and Manufacture》2006,46(12-13):1459-1468
This overview will focus on the direct fabrication of metal components by using laser-forming techniques in a layer-by-layer fashion. The main driving force of rapid prototyping (RP) or layer manufacturing techniques changed from fabrication of prototypes to rapid tooling (RT) and rapid manufacturing (RM). Nowadays, the direct fabrication of functional or structural end-use products made by layer manufacturing methods, i.e. RM, is the main trend. The present paper reports on the various research efforts deployed in the past decade or so towards the manufacture of metal components by different laser processing methods (e.g. selective laser sintering, selective laser melting and 3-D laser cladding) and different commercial machines (e.g. Sinterstation, EOSINT, TrumaForm, MCP, LUMEX 25, Lasform). The materials and applications suitable to RM of metal parts by these techniques are also discussed. 相似文献
56.
Sintering of Si3 N4 powder with the addition of a Y2 O3 + Al2 O3 mixture or YAlO3 as sintering aids was investigated. Sintering was improved in the case of YAlO3 additive compared to that for the Y2 O3 + Al2 O3 mixture. An initial delay in densification was most likely caused by heterogeneity of the liquid phase formed in the case of the separate oxide additions at temperatures above 1700°C. 相似文献
57.
Masamichi Akimoto Tetsuya Ishii Koji Yamagaki Kazuhisa Ohtaguchi Kozo Koide Kazunaga Yazawa 《Journal of the American Oil Chemists' Society》1990,67(12):911-915
Optimization of culture conditions for the growth rate, 5,8,11,14,17-cis-Eicosapentaenoic acid (EPA) content and EPA productivity of a bacterium isolated from Pacific mackerel intestines was investigated
by use of a culture medium containing 1.00 wt% peptone and 0.50 wt% yeast extract in an artificial sea water (ASW). Cultivation
temperature affected the growth rate and cellular EPA content of the bacterium. The cellular EPA content at 8°C was as great
as 16.8 mg/g of dry cells, which was more than two times greater than that at 25°C (7.3 mg/g of dry cells), although the growth
rate showed a maximum at 25°C. Both the yield of bacterial cells and the cellular EPA content at 25°C reached maximum values
when the pH of the culture medium was nearly 7.0 and when the concentration of ASW was 100% (v/v). Under optimum culture conditions
[25°C pH 7.0 and 100% (v/v) ASW], the amount of EPA accumulated in the cellular lipids reached 45.6 mg/L of culture broth
after 8 hr. 相似文献
58.
A fire whirl in an open space can cause devastating damage as was experienced in Hifukusho-ato, Tokyo, after the Great Kanto Earthquake in 1921. To understand the generation mechanism of the open-space fire whirls, 1/1000th scale-model experiments were conducted in a large, low-speed open-loop wind tunnel. In analyzing the experiments, there was found to be a critical lateral wind velocity that generated intense fire whirls. A scaling law that predicts the critical wind velocity was developed and validated by various data including scale-model experiments by other researchers and real urban fire whirls. A dimensional analysis is conducted to understand the effect of flow circulation on the increase in flame height. The simple analysis was supported by the results of numerical simulations by other researchers. 相似文献
59.
Kyomoto M Moro T Konno T Takadama H Kawaguchi H Takatori Y Nakamura K Yamawaki N Ishihara K 《Journal of materials science. Materials in medicine》2007,18(9):1809-1815
Osteolysis caused by wear particles from polyethylene in the artificial hip joints is a serious issue. We have used photo-induced
radical graft polymerization to graft 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer onto the surface of cross-linked
polyethylene (CLPE-g-MPC) in order to reduce friction and wear at the bearing surface of the joint. The physical and mechanical properties of CLPE
and CLPE-g-MPC were not significantly different, expect that the friction coefficient of untreated CLPE cups was 0.0075, compared with
0.0009 for CLPE-g-MPC cup, an 88% reduction. After 3.0 × 106 cycles in the hip joint simulator test, we could not observe any wear of CLPE-g-MPC cups. We concluded that the advantage of photo-induced radical graft polymerization technique was that the grafted MPC
polymer gave a high lubricity only on the surface and has no effect on the bulk properties of the CLPE substrate. 相似文献
60.
K Eto Y Tsubamoto Y Terauchi T Sugiyama T Kishimoto N Takahashi N Yamauchi N Kubota S Murayama T Aizawa Y Akanuma S Aizawa H Kasai Y Yazaki T Kadowaki 《Canadian Metallurgical Quarterly》1999,283(5404):981-985
Glucose metabolism in glycolysis and in mitochondria is pivotal to glucose-induced insulin secretion from pancreatic beta cells. One or more factors derived from glycolysis other than pyruvate appear to be required for the generation of mitochondrial signals that lead to insulin secretion. The electrons of the glycolysis-derived reduced form of nicotinamide adenine dinucleotide (NADH) are transferred to mitochondria through the NADH shuttle system. By abolishing the NADH shuttle function, glucose-induced increases in NADH autofluorescence, mitochondrial membrane potential, and adenosine triphosphate content were reduced and glucose-induced insulin secretion was abrogated. The NADH shuttle evidently couples glycolysis with activation of mitochondrial energy metabolism to trigger insulin secretion. 相似文献