全文获取类型
收费全文 | 227篇 |
免费 | 23篇 |
专业分类
电工技术 | 3篇 |
化学工业 | 57篇 |
金属工艺 | 2篇 |
机械仪表 | 7篇 |
建筑科学 | 15篇 |
能源动力 | 3篇 |
轻工业 | 27篇 |
武器工业 | 1篇 |
无线电 | 26篇 |
一般工业技术 | 28篇 |
冶金工业 | 4篇 |
原子能技术 | 4篇 |
自动化技术 | 73篇 |
出版年
2023年 | 3篇 |
2022年 | 3篇 |
2021年 | 6篇 |
2020年 | 9篇 |
2019年 | 4篇 |
2018年 | 5篇 |
2017年 | 5篇 |
2016年 | 9篇 |
2015年 | 14篇 |
2014年 | 8篇 |
2013年 | 14篇 |
2012年 | 7篇 |
2011年 | 16篇 |
2010年 | 14篇 |
2009年 | 8篇 |
2008年 | 17篇 |
2007年 | 15篇 |
2006年 | 4篇 |
2005年 | 8篇 |
2004年 | 13篇 |
2003年 | 9篇 |
2002年 | 7篇 |
2001年 | 1篇 |
2000年 | 3篇 |
1999年 | 4篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1991年 | 1篇 |
1987年 | 4篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 5篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1974年 | 3篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1969年 | 1篇 |
1962年 | 2篇 |
排序方式: 共有250条查询结果,搜索用时 31 毫秒
11.
12.
Zachary Freudenburg Khaterah Kohneshin Erik Aarnoutse Mariska Vansteensel Mariana Branco Sacha Leinders Max van den Boom Elmar G. M. Pels Nick Ramsey 《控制理论与应用(英文版)》2021,19(4):444-454
While brain computer interfaces (BCIs) offer the potential of allowing those suffering from loss of muscle control to once
again fully engage with their environment by bypassing the affected motor system and decoding user intentions directly from
brain activity, they are prone to errors. One possible avenue for BCI performance improvement is to detect when the BCI user
perceives the BCI to have made an unintended action and thus take corrective actions. Error-related potentials (ErrPs) are
neural correlates of error awareness and as such can provide an indication of when a BCI system is not performing according
to the user’s intentions. Here, we investigate the brain signals of an implanted BCI user suffering from locked-in syndrome
(LIS) due to late-stage ALS that prevents her from being able to speak or move but not from using her BCI at home on a
daily basis to communicate, for the presence of error-related signals. We first establish the presence of an ErrP originating
from the dorsolateral pre-frontal cortex (dLPFC) in response to errors made during a discrete feedback task that mimics the
click-based spelling software she uses to communicate. Then, we show that this ErrP can also be elicited by cursor movement
errors in a continuous BCI cursor control task. This work represents a first step toward detecting ErrPs during the daily
home use of a communications BCI. 相似文献
13.
Elmar Strassburger Thomas Hutzler Jens Klimke 《Journal of the American Ceramic Society》2013,96(9):2718-2721
Contrary to the moderate ballistic advantage of Al2O3 ceramics over MgAl2O4 polycrystals, the present study shows a reverse ratio of the ballistic strength of alumina and spinel single crystals: Spinel single crystals outperform sapphire and exhibit a similarly high stability as submicrometer Al2O3 ceramics. The results correlate with different cleavage of single crystalline spinel and sapphire, changing the fragmentation on ballistic impact. 相似文献
14.
Eric Biehler Frédéric Mayer Lucien Hoffmann Elmar Krause Torsten Bohn 《Journal of food science》2010,75(1):C55-C61
ABSTRACT: Carotenoids are C-40 tetraterpenoid compounds with potential health beneficial effects. Major dietary sources include a variety of fruits and vegetables. Rapid screening methods are therefore desired, but their accuracy varies depending on the carotenoid profile and the matrix of the plant food. In the present study, 3 different methods were compared, all based on a rapid extraction protocol and spectrophotometric measurements to determine the total amount carotenoids present in fruits and vegetables (n = 28), either with or without chlorophyll. Published methods (a) Lichtenthaler and (b) Hornero-Méndez and Mínguez-Mosquera were compared with a newly developed method (method c) based on the average molar absorption coefficient (135310 Lcm−1mol−1) and wavelength (450 nm in acetone), for the 5 predominant carotenoid species (beta-carotene, zeaxanthin, lycopene, lutein, beta-cryptoxanthin) in the investigated foods. All results were compared to HPLC (method d). To avoid overestimating carotenoid concentrations due to chlorophyll A and B presence, the effect of saponification was studied for all methods. Overall, saponification led to significant carotenoid losses (12.6 ± 0.9%). Methods a, b, c, and d yielded 5.1 ± 0.4 mg/100 g, 4.6 ± 0.5 mg/100 g, 4.3 ± 0.5 mg/100 g, and 4.2 ± 0.5 mg/100 g total carotenoids, respectively, with method a leading to significant higher mean concentrations compared to all other methods (P < 0.001, Bonferroni) with methods b and c being not significantly different and highly correlated compared to HPLC (> r = 0.95). Similar results were found when stratifying for chlorophyll content and fruits compared with vegetables, however, accuracy varied for individual fruits, highlighting the limitation to use the same method for all plant foods. Practical Application: This study presents a comparison of various rapid spectrophotometric measurements to determine total carotenoid content in various fruits and vegetables and could aid in the selection of the appropriate method for individual plant foods with different carotenoid profile and matrices. 相似文献
15.
Tim Piessens Michiel Steyaert Elmar Bach 《Analog Integrated Circuits and Signal Processing》2002,31(1):31-37
An open loop architecture for a reference voltage buffer in -converters is presented to achieve fast-settling, since the settling time of the references plays an important role in the global performance of sampled data converters. This design has been tested on a 2-1 -converter with an on-chip bandgap reference increasing the input related dynamic range up to 93.4 dB for a bandwidth of 99 kHz. 相似文献
16.
Prof. Dr. Hans Ulrich Buhl Dr. Bernd Heinrich Prof. Dr. Peter Loos Prof. Dr. Ulrich Frank Visiting Prof. Daniel L. Moody PhD Prof. Jeffrey Parsons PhD Prof. Dr. Michael Rosemann Prof. Dr. Elmar J. Sinz Prof. Ron Weber PhD Achim Kindler Dr. Prof. Dr. Claus Rautenstrauch Dipl.-Wirt.-Inf. Peter Fettke 《WIRTSCHAFTSINFORMATIK》2005,47(2):152-161
17.
Elmar Achenbach 《International Journal of Heat and Mass Transfer》1975,18(12):1387-1396
The total and local heat transfer from a smooth circular cylinder to the cross flow of air has been measured over the Reynolds number range 3 × 104 < Re < 4 × 106. The interaction between flow and heat transfer is discussed. In particular, the boundary-layer effects on the heat transfer, such as transition from laminar to turbulent flow or boundary-layer separation, are considered in conjunction with the distributions of local static pressure and skin friction. 相似文献
18.
It is illustrated that the intermediate frequency (IF) in an IF zero-crossing detector (ZXD) for Bluetooth basic rate transmission affects the transmission quality. A simple optimisation strategy is presented and it is shown that simple IF ZXD structures benefit more from the optimal choice of the IF than hypothesis detectors 相似文献
19.
Elmar K. Tschegg Stefan Herndler Patrick Weninger Michael Jamek Stefanie Stanzl-Tschegg Heinz Redl 《Materials science & engineering. C, Materials for biological applications》2008,28(8):1203-1208
A testing method has been developed to characterize stiffness and permanent deformation of bone-implant systems. The system consists of an artificial tibia with simulated distal fracture stabilized by an unreamed intramedullary nail. This system was loaded with three different sequences at 2 Hz, each consisting of 40,000 sinusoidal cycles, simulating clinical relevant loading conditions. Evaluation of the results showed a stiffness of 2782 N/mm with a standard deviation of 311 N/mm and a permanent deformation of 0.64 mm with a standard deviation of 0.21 mm. The locking screws broke exclusively during the third loading sequence starting with the most proximal of the distal screws. The study provides a standard technique for biomechanical testing and a comparison of different bone/implant-systems avoiding the variability of cadaver bone tests. 相似文献
20.