全文获取类型
收费全文 | 345篇 |
免费 | 3篇 |
专业分类
电工技术 | 8篇 |
化学工业 | 82篇 |
金属工艺 | 6篇 |
机械仪表 | 5篇 |
能源动力 | 13篇 |
轻工业 | 13篇 |
石油天然气 | 1篇 |
无线电 | 20篇 |
一般工业技术 | 51篇 |
冶金工业 | 106篇 |
原子能技术 | 18篇 |
自动化技术 | 25篇 |
出版年
2022年 | 3篇 |
2021年 | 9篇 |
2020年 | 2篇 |
2019年 | 1篇 |
2018年 | 6篇 |
2017年 | 3篇 |
2016年 | 6篇 |
2015年 | 4篇 |
2014年 | 13篇 |
2013年 | 13篇 |
2012年 | 11篇 |
2011年 | 20篇 |
2010年 | 10篇 |
2009年 | 15篇 |
2008年 | 15篇 |
2007年 | 14篇 |
2006年 | 11篇 |
2005年 | 7篇 |
2004年 | 8篇 |
2003年 | 7篇 |
2002年 | 10篇 |
2001年 | 3篇 |
2000年 | 4篇 |
1999年 | 5篇 |
1998年 | 23篇 |
1997年 | 26篇 |
1996年 | 25篇 |
1995年 | 15篇 |
1994年 | 11篇 |
1993年 | 12篇 |
1992年 | 2篇 |
1991年 | 4篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 5篇 |
1986年 | 3篇 |
1985年 | 2篇 |
1984年 | 9篇 |
1982年 | 1篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1970年 | 1篇 |
排序方式: 共有348条查询结果,搜索用时 15 毫秒
101.
Yasunari?Takagi Osamu?MizunoEmail author Tohru?Kikuno 《Empirical Software Engineering》2005,10(4):495-515
During software development, projects often experience risky situations. If projects fail to detect such risks, they may exhibit
confused behavior. In this paper, we propose a new scheme for characterization of the level of confusion exhibited by projects
based on an empirical questionnaire. First, we designed a questionnaire from five project viewpoints, requirements, estimates,
planning, team organization, and project management activities. Each of these viewpoints was assessed using questions in which
experience and knowledge of software risks are determined. Secondly, we classify projects into “confused” and “not confused,”
using the resulting metrics data. We thirdly analyzed the relationship between responses to the questionnaire and the degree
of confusion of the projects using logistic regression analysis and constructing a model to characterize confused projects.
The experimental result used actual project data shows that 28 projects out of 32 were characterized correctly. As a result,
we concluded that the characterization of confused projects was successful. Furthermore, we applied the constructed model
to data from other projects in order to detect risky projects. The result of the application of this concept showed that 7
out of 8 projects were classified correctly. Therefore, we concluded that the proposed scheme is also applicable to the detection
of risky projects. 相似文献
102.
Y Kuniyoshi K Koja M Akasaki K Miyagi M Shimoji M Kudaka T Uezu K Arakaki H Sakuta Y Kamada 《Canadian Metallurgical Quarterly》1998,28(11):1206-1209
We report herein the case of a patient in whom aneurysms of the bilateral deep femoral arteries (DFA) and multiple iliac aneurysms associated with severe aortic valve disease were successfully treated by a two-staged operation. The patient was a 74-year-old man who had dense calcification of the ascending aorta and aortic arch. Prior to aortic valve replacement (AVR), the aneurysms of the DFA and internal iliac arteries were resected. The terminal end of the abdominal aorta and bilateral common iliac arteries were then reconstructed with a Y graft to be used as a possible alternative arterial input route in place of the ascending aorta for extracorporeal circulation during the AVR. The inferior mesenteric artery (IMA) was well developed, and the external iliac arteries and their branches were preserved at aneurysmectomy. Postoperatively, there was no ischemia of the pelvic organs or the hip muscles. The AVR was subsequently performed 5 weeks after the first operation, and the patient was discharged after an uneventful postoperative course. 相似文献
103.
Keiichi Kamada Kouichi Nawashiro Fumiyasu Tamagawa Cha-Yeol Lee Hiroshi Yoshida Sunao Kawasaki Ritoku Ando Masaru Masuzaki 《Journal of Infrared, Millimeter and Terahertz Waves》2000,21(9):1441-1449
A relativistic electron beam (500 keV, 200 A, 10 ns) generated magnetically tunable microwave radiation in a frequency range of 9-13 GHz when it is injected into an X-band rectangular waveguide immersed in a uniform axial magnetic field (4-10 kG). The mechanism of the microwave radiation was identified as the gyrotron backward wave interaction. The output power of the radiated microwave increased exponentially with the increase of the cavity length. 相似文献
104.
Inside Cover: Furospinosulin‐1, Marine Spongean Furanosesterterpene,Suppresses the Growth of Hypoxia‐Adapted Cancer Cells by Binding to Transcriptional Regulators p54nrb and LEDGF/p75 (ChemBioChem 2/2016) 下载免费PDF全文
105.
A.Yoshikawa T.Yanagida Y.Yokota K.Kamada N.Kawaguchi K.Fukuda A.Yamazaki K.Watanabe A.Uritani T.Iguchi G.Boulon M.Nikl 《中国稀土学报(英文版)》2011,(12):1178-1182
Two topics were focused.The first one was about the gamma-ray scintillator,Pr3+:Lu3Al5O12(LuAG) .The second one was about neutron scintillator,Ce3+:6LiCaAlF6 and Eu2+:6LiCaAlF6(6LiCAF) .Those scintillators have been developed very recently for modern imaging appli-cations in the medical and homeland security fields.In both cases,the rare earth ions are playing the crucial role as emission centers.Pr3+ in LuAG provided fast 5d→4f transition providing noticeably shorter decay time than that of Ce3+.Among several candidate hosts,LuAG showed the best performance.Bulk crystal growth,basic scintillation properties,two-dimensional gamma-ray imaging and positron emission mammography(PEM) application were demonstrated.Due to the international situation,the homeland security was compromized by illicit traffic of explosives,drugs,nuclear materials,etc.and the ways to its improvement became an important R&D topic.For this purpose the Ce and Eu doped LiCAF ap-peared competitive candidates.Especially,when substitution of 3He neutron detectors was considered,the discrimination ability of gamma-ray from alpha-ray was important.Bulk crystal growth,basic scintillation properties and two-dimensional neutron imaging were demonstrated. 相似文献
106.
The Gaussian Solar Flux model (GSFM) predicts instantaneous hourly and integrated daily direct and diffuse solar flux upon sloped as well as horizontal surfaces for clear and cloudy days. Comparison with Davis SEMRTS data from the first six months of 1981 indicates a mean relative error of +/−3.5% and a correlation coefficient of 0.999 for instantaneous global flux during clear days.The GSFM improves upon previous monolayer models with cloud transmittance functions generalized for different surface albedos and a fast Gaussian quadrature based estimate for water vapor pathlengths. Advantages over multilayer models are its speed and lack of need for soundings. Input may be made entirely from standard surface meteorological measurements. 相似文献
107.
The JT-60SA experiment is one of the three projects to be undertaken in Japan as part of the Broader Approach Agreement, conducted jointly by Europe and Japan, and complementing the construction of ITER in Europe. It is a fully superconducting tokamak capable of confining break-even equivalent deuterium plasmas with equilibria covering high plasma shaping with a low aspect ratio at a maximum plasma current of Ip = 5.5 MA. In late 2007 the BA Parties, prompted by cost concerns, asked the JT-60SA Team to carry out a re-baselining effort with the purpose to fit in the original budget while aiming to retain the machine mission, performance, and experimental flexibility. Subsequently the Integrated Project Team has undertaken a machine re-optimization followed by engineering design activities aimed to reduce costs while maintaining the machine radius and plasma current. This effort led the Parties to the approval of the new design in late 2008 and hence final design and procurement activities have commenced. The paper will describe the process leading to the re-baselining, the resulting final design and technical solutions and the present status of procurement activities. 相似文献
108.
HIGFETs were fabricated using an AlInAs/GaInAs heterostructure grown by MOCVD. The 1 mu m-gate HIGFET showed a maximum transconductance of 740 mS/mm at room temperature, which is the highest transconductance obtained for HIGFETs. The reduction of the AlInAs layer thickness to 30 nm and the low source resistance are the primary reasons for this enhancement.<> 相似文献
109.
110.
H. Weman H. Kamada M. Potemski J. Temmyo R. N tzel T. Tamamura 《Solid-state electronics》1996,40(1-8):379-382
We have measured the optical properties of self-organized strained InGaAs quantum disks in high magnetic fields. The disks are formed during spontaneous reorganization of a sequence of AlGaAs and strained InGaAs epitaxial films grown on GaAs (311)B substrates by metallorganic vapor-phase epitaxy. The magneto-luminescence properties of these InGaAs quantum disks have been studied for various disks sizes with lateral widths from 100 nm down to 20 nm. We have confirmed that when the lateral confinement exists the exciton binding energy increases even when the spatial extent of the effective potential is greater than the exciton in-plane Bohr radius. This enhancement starts being noticeable when the spatial extent of the potential is two, three times larger than the Bohr radius, where the center-of-mass quantization is negligibly small. 相似文献