全文获取类型
收费全文 | 295篇 |
免费 | 8篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 66篇 |
金属工艺 | 5篇 |
机械仪表 | 5篇 |
建筑科学 | 23篇 |
能源动力 | 9篇 |
轻工业 | 31篇 |
水利工程 | 1篇 |
无线电 | 21篇 |
一般工业技术 | 30篇 |
冶金工业 | 37篇 |
原子能技术 | 1篇 |
自动化技术 | 74篇 |
出版年
2023年 | 1篇 |
2022年 | 6篇 |
2021年 | 13篇 |
2020年 | 2篇 |
2019年 | 4篇 |
2018年 | 6篇 |
2017年 | 2篇 |
2016年 | 8篇 |
2015年 | 2篇 |
2014年 | 5篇 |
2013年 | 20篇 |
2012年 | 22篇 |
2011年 | 15篇 |
2010年 | 20篇 |
2009年 | 14篇 |
2008年 | 21篇 |
2007年 | 20篇 |
2006年 | 19篇 |
2005年 | 12篇 |
2004年 | 10篇 |
2003年 | 13篇 |
2002年 | 8篇 |
2001年 | 4篇 |
2000年 | 4篇 |
1999年 | 8篇 |
1998年 | 5篇 |
1997年 | 5篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 3篇 |
1993年 | 4篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1981年 | 1篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1973年 | 1篇 |
排序方式: 共有304条查询结果,搜索用时 15 毫秒
11.
Jong-Tae Park Antonius Suwanto Irawan Tan Tommy Nuryanto Rudy Lukman Kan Wang Jay-lin Jane 《Food science and biotechnology》2014,23(1):125-132
An α-amylase gene was cloned from the thermophilic bacterium Bacillus subtilis isolated from Indonesian oil palm shell waste. The gene expressed an extracellular enzyme. Optimal hydrolysis conditions for the enzyme were 70°C and pH 6.0. The specific activity of the enzyme was 16.0 kU per mg of protein, which was higher than for other thermostable amylases. Hydrolytic products of the enzyme using starch and glycogen were mainly maltohexaose and maltopentaose. The enzyme had a K m value of 0.099 mg/mL for amylopectin, more than 10 times lower than for amylose. The catalytic efficiency of the enzyme using amylopectin was 39,200 mL/mg·s and was 3,270 mL/mg·s using amylose. The enzyme liquefied corn starch at pH 5.0, which was successfully converted to glucose using commercial glucoamylase and pullulanase without pH adjustment. The enzyme has advantages for industrial applications. 相似文献
12.
This paper solves the fair and optimal house allocation problem (Sun and Yang, Econ Lett 81:73–79, 2003) when the agents preferences
are represented by nonlinear utility functions using techniques for global mixed integer nonlinear optimization. A small simulation
study indicates that if quasi-linear specifications are adopted as approximations to nonlinear utility functions and if the
fair and optimal allocation is identified based on this approximation, then the prices are typically higher on average and
the resulting allocation is typically non-fair. 相似文献
13.
In situ time-series measurements of spectral diffuse downwelling irradiance from the Bermuda Testbed Mooring are presented. Averaged diffuse attenuation coefficients of downwelling irradiance, Kd,and their elastic and inelastic components are investigated at seven wavelengths. At shorter wavelengths (<510 nm), Kd is weakly dependent on the solar zenith angle owing to the prevailing scattering effect and therefore can be considered a quasi-inherent optical property. At longer wavelengths (>510 nm), Kd shows a strong dependence on the solar zenith angle. As depth increases, inelastic scattering plays a greater role for the underwater light field at red wavelengths. 相似文献
14.
Sitao Wu Tommy W. S. Chow Kai Tat Ng Kim Fung Tsang 《Neural computing & applications》2006,15(3-4):298-309
This paper describes an improvement of borrowing channel assignment (BCA) for patterned traffic load by using the short-term traffic prediction ability of cellular probabilistic self-organizing map (CPSOM). The fast growing cellular mobile systems demand more efficient and faster channel allocation techniques today. In case of patterned traffic load, the traditional BCA methods are not efficient to further enhance the performance because heavy-traffic cells cannot borrow channels from their neighboring cells with light or medium traffic that may have unused nominal channels. The performance can be increased if the short-term traffic load can be predicted. The predicted results can then be used for channel re-assignment. Therefore, the unused nominal channels of the light-or-medium-traffic cells can be transferred to the heavy-traffic cells that need more nominal channels. In this paper, CPSOM is used online for traffic prediction. In this sense, the proposed CPSOM-based BCA method is able to enhance the performance for patterned traffic load compared with the traditional BCA methods. Simulation results corroborate that the proposed method enables the system to work with better performance for patterned traffic load than the traditional BCA methods. 相似文献
15.
Kirk J. King Tommy L. Johnson 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1984,227(2):257-258
A high energy gamma ray calibration source is obtained by the fast neutron irradiation of polytetrafluoride and lead. 相似文献
16.
In this paper, a novel feature selection method based on rough sets and mutual information is proposed. The dependency of each feature guides the selection, and mutual information is employed to reduce the features which do not favor addition of dependency significantly. So the dependency of the subset found by our method reaches maximum with small number of features. Since our method evaluates both definitive relevance and uncertain relevance by a combined selection criterion of dependency and class-based distance metric, the feature subset is more relevant than other rough sets based methods. As a result, the subset is near optimal solution. In order to verify the contribution, eight different classification applications are employed. Our method is also employed on a real Alzheimer’s disease dataset, and finds a feature subset where classification accuracy arrives at 81.3 %. Those present results verify the contribution of our method. 相似文献
17.
Tammy Ben-Yaacov Tommy Ive Chris G. Van de Walle Umesh K. Mishra James S. Speck Steven P. Denbaars 《Journal of Electronic Materials》2010,39(5):608-611
We investigated the properties of indium-doped zinc oxide layers grown by metalorganic chemical vapor deposition on semi-insulating
GaN(0001) templates. Specular and transparent films were grown with n-type carrier concentrations up to 1.82 × 1019 cm−3 as determined by Hall measurements, and all In-doped films had carrier concentrations significantly higher than that of a
comparable undoped film. For low In flows, the carrier concentration increased accordingly with trimethyl-indium (TMIn) flow
until a maximum carrier concentration of 1.82 × 1019 cm−3 was realized. For higher In flows, the carrier concentration decreased with increasing TMIn flow rate. Sheet resistance as
low as 185 Ω/sq was achieved for the In-doped films, which is a significant decrease from that of a comparable undoped ZnO
film. Our n-type doping studies show that In is an effective dopant for controlling the n-type conductivity of ZnO. 相似文献
18.
Zihong Liu Tommy E. Cousins John J. Lesko Elisa D. Sotelino 《Canadian Metallurgical Quarterly》2008,12(6):660-668
No appropriate provisions from either AASHTO Standard (2002) or AASHTO LRFD (2004) bridge design specifications are available for the design of fiber-reinforced polymer (FRP)-deck-on-steel-superstructure bridges. In this research, a parametric study using the finite-element method (FEM) is conducted to examine two design issues concerning the design of FRP-deck-on-steel-superstructure bridges, namely deck relative deflection and load distribution factor (LDF). Results show that the strip method specified in AASHTO LRFD specification as an approximate method of analysis, can also be applied to FRP decks as a practical method. However, different strip width equations have to be determined by either FEM or experimental methods for different types of FRP decks. In this study, one such equation has been derived for the Strongwell deck. In addition, both FEM results and experimental measurements show that the AASHTO LDF equations for glued laminated timber decks on steel stringers provide good estimations of LDF for FRP-deck-on-steel-superstructure bridges. Finally, it is found that the lever rule can be used as an appropriately conservative design method to predict the LDF of FRP-deck-on-steel-superstructure bridges. 相似文献
19.
Rabby Xiao Yang Zhang Tommy Liu 《中国电子商情》2010,(9):54-55
在低于40纳米的超深亚微米VLSI设计中,时钟树网络在电路时序收敛、功耗、PVT变异容差和串扰噪声规避方面所起的作用要更重要得多。 相似文献
20.
65纳米设计时序收敛问题介绍时序收敛一直是当代ASIC设计物理实现的主要问题,特别是对于那些用于通信产品中的ASIC来说更是如此。我们有一项65纳米ASIC就是这种设计。它拥有2400万门数和4400万内存位,大部分逻辑将一直以400MHz 相似文献