全文获取类型
收费全文 | 457篇 |
免费 | 10篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 5篇 |
化学工业 | 52篇 |
金属工艺 | 26篇 |
机械仪表 | 12篇 |
建筑科学 | 18篇 |
矿业工程 | 2篇 |
能源动力 | 13篇 |
轻工业 | 67篇 |
水利工程 | 3篇 |
石油天然气 | 1篇 |
无线电 | 35篇 |
一般工业技术 | 81篇 |
冶金工业 | 61篇 |
原子能技术 | 1篇 |
自动化技术 | 92篇 |
出版年
2023年 | 4篇 |
2022年 | 3篇 |
2021年 | 17篇 |
2020年 | 9篇 |
2019年 | 10篇 |
2018年 | 17篇 |
2017年 | 6篇 |
2016年 | 7篇 |
2015年 | 8篇 |
2014年 | 21篇 |
2013年 | 30篇 |
2012年 | 20篇 |
2011年 | 18篇 |
2010年 | 25篇 |
2009年 | 22篇 |
2008年 | 27篇 |
2007年 | 22篇 |
2006年 | 15篇 |
2005年 | 16篇 |
2004年 | 11篇 |
2003年 | 14篇 |
2002年 | 12篇 |
2001年 | 11篇 |
2000年 | 8篇 |
1999年 | 4篇 |
1998年 | 17篇 |
1997年 | 9篇 |
1996年 | 8篇 |
1995年 | 5篇 |
1994年 | 7篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1987年 | 2篇 |
1982年 | 2篇 |
1981年 | 6篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1972年 | 2篇 |
1960年 | 2篇 |
1944年 | 2篇 |
1943年 | 6篇 |
1934年 | 2篇 |
1932年 | 2篇 |
1930年 | 2篇 |
1929年 | 3篇 |
1928年 | 3篇 |
1927年 | 2篇 |
1912年 | 1篇 |
排序方式: 共有469条查询结果,搜索用时 62 毫秒
21.
This paper illustrates the needs and challenges for the management of distributed manufacturing in a multi-company supply chain and processes these further as features of new IT systems. Requirements are collected from manufacturing companies and combined with insights from literature in the field of current ERP/MES system drawbacks, advantages, needs and challenges. The findings show that the needs and challenges in data integration inside SME networks are closely related to the limitations of current supply chain solutions. Current ERP-solutions lack extended enterprise support and a shared cloud-based approach. On the other hand, current MES solutions can operate the manufacturing process, but not for distributed manufacturing. As an answer to the requirements, we made a proposal for the core of architecture for next generation of MES solution in this position paper. Moreover, a pilot software tool has been developed to support the needs related to real time, cloud-based, light weight operation. 相似文献
22.
The oxidation of AISI 316L(NG) stainless steel in simulated pressurised water reactor (PWR) coolant with or without addition of 1 ppm Zn at 280 °C for up to 96 h has been characterised in situ by electrochemical impedance spectroscopy (EIS), both at the corrosion potential and under anodic polarisation up to 0.5 V vs. the reversible hydrogen electrode (RHE). Additional tests were performed in simulated PWR coolant with the addition of 0.01 M Na2B4O7 to exclude the effect of pH excursions probably due to Zn hydrolysis reactions. The thickness and in-depth composition of the oxide films formed at open circuit and at 0.5 V vs. RHE in the investigated electrolytes have been estimated from X-ray photoelectron spectroscopy (XPS) depth profiles. The kinetic and transport parameters characterising the oxide layer growth have been estimated using a calculational procedure based on the mixed conduction model for oxide films. Successful simulations of both the EIS and XPS data have been obtained. The parameter estimates are discussed in terms of the effect of Zn on the oxide layers on stainless steel in PWR conditions. 相似文献
23.
The effect of weighting on the uncertainty of the discrete time Fourier transform (DTFT) samples of a signal corrupted by additive noise is investigated. Making very weak assumptions, it is shown how the adopted window sequence and the autocovariance function of the noise affect the second-order stochastic moments of the frequency-domain data. The relationship obtained extends the results reported in the literature and is useful in many frequency-domain estimation problems. It is shown how the knowledge of the second-order moments of the transform has allowed the application of the least squares technique for the estimation of the parameters of a multifrequency signal in the frequency-domain. The estimator obtained is very useful when high-accuracy results are required under real-time constraints. The procedure exhibits a better accuracy than similar frequency-domain methods proposed in the literature 相似文献
24.
25.
Ohne Zusammenfassung 相似文献
26.
27.
Carbone P. Buglione L. Mari L. Petri D. 《IEEE transactions on instrumentation and measurement》2008,57(2):235-241
In this paper, we discuss basic issues related to measurements performed in the domains of software engineering and metrology. Similarities and differences are highlighted, with the aim of analyzing the level of knowledge in both domains. A theoretical approach is followed, allowing the proposal of a measurement process model, which is used as a guiding scheme throughout the paper to illustrate peculiarities arising when taking software measurements. Common ground between metrologists and software engineers are described by discussing foundations of measurement in the software context. 相似文献
28.
冲击干燥提高效率和产能 总被引:1,自引:0,他引:1
Kari Juppi Petri Norri 《中华纸业》2008,(22)
对美卓造纸机械的冲击干燥装置进行了简述。将冲击干燥与传统干燥的蒸发效率进行了比较,对比结果表明了冲击干燥装置的优越性。 相似文献
29.
30.