全文获取类型
收费全文 | 2088篇 |
免费 | 26篇 |
专业分类
电工技术 | 6篇 |
综合类 | 1篇 |
化学工业 | 100篇 |
金属工艺 | 9篇 |
机械仪表 | 19篇 |
建筑科学 | 26篇 |
能源动力 | 20篇 |
轻工业 | 53篇 |
水利工程 | 5篇 |
石油天然气 | 1篇 |
无线电 | 59篇 |
一般工业技术 | 100篇 |
冶金工业 | 1654篇 |
原子能技术 | 2篇 |
自动化技术 | 59篇 |
出版年
2023年 | 8篇 |
2022年 | 10篇 |
2021年 | 15篇 |
2020年 | 14篇 |
2019年 | 18篇 |
2018年 | 10篇 |
2017年 | 18篇 |
2016年 | 18篇 |
2015年 | 17篇 |
2014年 | 23篇 |
2013年 | 32篇 |
2012年 | 24篇 |
2011年 | 42篇 |
2010年 | 25篇 |
2009年 | 19篇 |
2008年 | 28篇 |
2007年 | 17篇 |
2006年 | 19篇 |
2005年 | 12篇 |
2004年 | 10篇 |
2003年 | 12篇 |
2002年 | 3篇 |
2001年 | 9篇 |
2000年 | 5篇 |
1999年 | 54篇 |
1998年 | 501篇 |
1997年 | 272篇 |
1996年 | 213篇 |
1995年 | 99篇 |
1994年 | 83篇 |
1993年 | 106篇 |
1992年 | 18篇 |
1991年 | 22篇 |
1990年 | 25篇 |
1989年 | 25篇 |
1988年 | 30篇 |
1987年 | 44篇 |
1986年 | 25篇 |
1985年 | 30篇 |
1984年 | 5篇 |
1983年 | 7篇 |
1982年 | 10篇 |
1981年 | 13篇 |
1980年 | 10篇 |
1979年 | 2篇 |
1978年 | 4篇 |
1977年 | 31篇 |
1976年 | 69篇 |
1973年 | 2篇 |
1955年 | 1篇 |
排序方式: 共有2114条查询结果,搜索用时 0 毫秒
111.
112.
113.
114.
MW Byrne 《Canadian Metallurgical Quarterly》1997,2(4):27-34
Preventive services to assist parents to understand their children's developmental needs and to devise positive, culturally appropriate strategies for managing them are not recognized as important by most third party health service payers, especially managed care programs. Room-To-Grow is an intervention designed to meet identified community needs in a culturally appropriate and sensitive way. This article discusses the evolution of this intervention and the problems encountered in finding appropriate reimbursement streams. 相似文献
115.
Young Hoon Lee Myoungsoo Ham Bruce Yoo Jae Sun Lee 《The International Journal of Advanced Manufacturing Technology》2009,41(5-6):568-579
Operations management in a complex manufacturing environment is practiced hierarchically: production planning and scheduling in sequence since the integrated approach is not efficient and practical. Production targets and allocation to the equipment are determined in the planning procedure by considering the only the critical factors, and the detailed scheduling is determined with more information needed to accomplish the production targets provided in the planning step. There is always, therefore, a gap between the planning and scheduling procedure, and some control parameters or factors are used to control those gaps. In this paper an approach connecting two procedures is suggested, which can be applied in the EDS (electrical die sorting) or the probe process in the semiconductor manufacturing. The EDS process requires very flexible operation management since the manufacturing processing time is relatively short and the supply of upstream fabrication and the demand of downstream assembly have to be met simultaneously. Daily planning and scheduling procedure are modeled to minimize the tester change-over within the daily target. Because of the relatively long setup change-over time, daily planning and scheduling have to be performed so that the time needed for the device and probe card change is minimized as possible. Mathematical programming is suggested for the problem, and the modified model is developed which can be solved in a practical computational time on a daily base. The scheduling heuristic with the planning data obtained from the suggested model, is designed, and their performance is evaluated through the computational experiment. 相似文献
116.
HC Kwaan M Levin S Sakurai O Kucuk MW Rooney LJ Lis JW Kauffman 《Canadian Metallurgical Quarterly》1997,26(6):1061-1068
Digital gangrene was observed in a patient who had angiographic findings of digital arterial occlusion. The patient's blood showed a marked red blood cell aggregation with rouleaux formation in long chains, which could not be dispersed at shear rates up to 200 sec-1. Studies of the patient's blood revealed the presence of an abnormal fibrinogen capable of aggregating normal red blood cells. This fibrinogen was found by Raman spectroscopy to have an increased alpha-helical content, whereas the beta-sheet content was decreased. Defibrinogenation therapy with ancrod resulted in a dramatic symptomatic relief. The disappearance of the abnormal fibrinogen 6 months later and an absence of a family history indicate that this dysfibrinogenemia was acquired. 相似文献
117.
118.
In this paper, we introduce a novel standing wave oscillator (SWO) utilizing standing-wave-adaptive tapered transmission lines. This structure enhances Q and lowers phase noise through loss-reducing shaping of the transmission line, such that it is adapted to the position-dependent amplitudes of standing waves. Measurements validate the advantages of the proposed technique. The phase noise of a MOS SWO with the tapered line is 5-10 dB less than that of a uniform-line MOS SWO over a wide range of offset frequencies, centered about 15 GHz. Demonstrating a valuable exploitation of standing wave properties, the novel design concept boosts the potential for the emergence of standing wave oscillators as a useful alternative to the traditional lumped LC oscillator. 相似文献
119.
120.