全文获取类型
收费全文 | 471篇 |
免费 | 4篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 10篇 |
综合类 | 11篇 |
化学工业 | 14篇 |
金属工艺 | 79篇 |
机械仪表 | 168篇 |
建筑科学 | 31篇 |
矿业工程 | 30篇 |
能源动力 | 34篇 |
轻工业 | 2篇 |
水利工程 | 1篇 |
石油天然气 | 2篇 |
武器工业 | 3篇 |
无线电 | 9篇 |
一般工业技术 | 38篇 |
冶金工业 | 14篇 |
自动化技术 | 30篇 |
出版年
2024年 | 1篇 |
2023年 | 4篇 |
2022年 | 5篇 |
2021年 | 10篇 |
2020年 | 6篇 |
2019年 | 5篇 |
2018年 | 9篇 |
2017年 | 8篇 |
2016年 | 12篇 |
2015年 | 10篇 |
2014年 | 24篇 |
2013年 | 23篇 |
2012年 | 26篇 |
2011年 | 35篇 |
2010年 | 19篇 |
2009年 | 29篇 |
2008年 | 14篇 |
2007年 | 36篇 |
2006年 | 29篇 |
2005年 | 28篇 |
2004年 | 18篇 |
2003年 | 19篇 |
2002年 | 25篇 |
2001年 | 10篇 |
2000年 | 14篇 |
1999年 | 23篇 |
1998年 | 7篇 |
1997年 | 7篇 |
1996年 | 4篇 |
1995年 | 1篇 |
1994年 | 6篇 |
1993年 | 5篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
排序方式: 共有476条查询结果,搜索用时 15 毫秒
1.
An experimental investigation was carried out to examine the tribological behavior of NAO (non-asbestos organic) type brake linings containing different volume ratios of graphite and antimony trisulfide (Sb2S3). A scale dynamometer was used for friction tests and particular emphases were given to the effect of applied pressure, sliding speed, and temperature on the coefficient of friction according to the relative amounts of the two solid lubricants. Results showed that the brake linings with both solid lubricants exhibited better friction stability and less speed sensitivity than the friction materials containing a single solid lubricant. In particular, the brake lining containing higher concentrations of graphite showed better fade resistance than others during high-temperature friction test. 相似文献
2.
当地弹性地基梁法计算非岩石地基的水闸底板应力时,首先要求解出不平衡剪力,当闸墩截面选择梯形时(主要是边墩),常用方法是作图法,这既有误差又繁琐。所以就此推导出一个公式,可直接求解平衡剪力。 相似文献
3.
4.
汽车工业的发展对刹车系统的关键零部件——刹车盘的抗冲击韧性提出了更高的要求。研究结果表明,把灰铸铁(HT250)与用优质碳素结构钢25Mn预先冲压成型的钢件镶铸在一起制成的1种新型刹车盘,既具有灰铸铁良好的抗磨、减震、尺寸稳定等性能,又具有较高的抗冲击韧性,能够满足汽车工业高速化、轻量化对刹车盘的综合要求。 相似文献
5.
6.
This paper presents the implementation and vehicle tests of a vehicle longitudinal control scheme for Stop and Go cruise control.
The control scheme consists of a vehicle-to-vehicle distance control algorithm and throttle/brake control algorithm for acceleration
tracking. The desired acceleration of a vehicle for vehicle-to-vehicle distance control has been designed using Linear Quadratic
optimal control theory. Performance of the control algorithm has been investigated via vehicle tests. A millimeter wave radar
sensor has been used for distance measurement. A stepper motor and an electronic vacuum booster have been used for throttle/
brake actuators, respectively. It has been shown that the proposed control algorithm can provide satisfactory performance. 相似文献
7.
Seong-Won?NamEmail author Hyeong-Jin?Kim 《Journal of Mechanical Science and Technology》2002,16(6):776-784
We have performed experimental studies for the improvements of pneumatic brake systems of freight trains. Currently, most
of the freight trains operated by the Korean National Railroad have either empty-load or diaphragm type brake systems. In
this study, appropriate methods that the air pressure characteristics in both type of brake systems are in accordance with
each other have been investigated. We have also performed running tests using a 30 car-train set to design optimum capacity
of a quick release valve. The test results show that the quick release valve is considerably effective in shortening the release
time of the diaphragm type brake system. In the case of a normal brake application, the diaphragm type brake system with the
quick release valve reduces the release time to 34% of that of the system without the quick release valve. This release time
is almost equivalent to that of the empty-load type brake system. Accordance of braking performance in different types of
brake systems in a train set is expected to prevent wheel flats and to reduce maintenance costs. 相似文献
8.
9.
《Ergonomics》2012,55(6):828-836
Adaptive cruise control (ACC) requires that the driver intervene in situations that exceed the capability of ACC. A brake pulse might provide a particularly compatible means of alerting the driver to situations in which the acceleration authority of the ACC has been exceeded. This study examined the sensitivity of the driver to brake pulses of five different amplitudes (0.01–0.025 g) and five different durations (50–800 ms). Drivers were sensitive to accelerations as low as 0.015 g. Pulse duration interacted with pulse amplitude, such that moderate duration pulses were more detectable than long and short duration pulses at intermediate levels of pulse amplitude. A power function with an exponent of 1.0 accounted for 99% of the variance in drivers' sensitivity to pulse amplitude; however, a power function with an exponent of 0.23 accounted for only 70% of the variance in drivers' sensitivity to pulse duration. These results can help designers create ACC algorithms and develop brake pulse warnings. 相似文献
10.
Duan-Yu Chen Chia-Hsun Chen 《Journal of Visual Communication and Image Representation》2012,23(3):586-597
In nighttime driving brake lights are particularly important because they offer a warning signal to prevent potential collisions. In this work, we propose a novel visual-based approach for nighttime brake light detection using three-dimensional Nakagami imaging to analyze tail lights of vehicles in front. Rather than heuristic features, such as symmetry of taillights and appearance of the third brake light, the proposed approach extracts invariant features by modeling the scattering of brake lights, thus allowing detection to proceed in a part-based manner. Experiments from extensive datasets show that the proposed system can effectively detect vehicle braking under different lighting and traffic conditions, making it a realistic option for real-world applications. 相似文献