全文获取类型
收费全文 | 1004篇 |
免费 | 11篇 |
国内免费 | 6篇 |
专业分类
电工技术 | 46篇 |
综合类 | 44篇 |
化学工业 | 92篇 |
金属工艺 | 133篇 |
机械仪表 | 249篇 |
建筑科学 | 18篇 |
矿业工程 | 12篇 |
能源动力 | 178篇 |
轻工业 | 10篇 |
水利工程 | 11篇 |
石油天然气 | 37篇 |
武器工业 | 6篇 |
无线电 | 22篇 |
一般工业技术 | 52篇 |
冶金工业 | 24篇 |
原子能技术 | 19篇 |
自动化技术 | 68篇 |
出版年
2024年 | 1篇 |
2023年 | 6篇 |
2022年 | 14篇 |
2021年 | 19篇 |
2020年 | 16篇 |
2019年 | 12篇 |
2018年 | 14篇 |
2017年 | 14篇 |
2016年 | 13篇 |
2015年 | 31篇 |
2014年 | 45篇 |
2013年 | 30篇 |
2012年 | 60篇 |
2011年 | 78篇 |
2010年 | 35篇 |
2009年 | 36篇 |
2008年 | 34篇 |
2007年 | 69篇 |
2006年 | 59篇 |
2005年 | 61篇 |
2004年 | 63篇 |
2003年 | 47篇 |
2002年 | 38篇 |
2001年 | 33篇 |
2000年 | 31篇 |
1999年 | 33篇 |
1998年 | 29篇 |
1997年 | 13篇 |
1996年 | 17篇 |
1995年 | 24篇 |
1994年 | 8篇 |
1993年 | 6篇 |
1992年 | 8篇 |
1991年 | 5篇 |
1990年 | 6篇 |
1989年 | 5篇 |
1988年 | 2篇 |
1987年 | 4篇 |
1986年 | 2篇 |
排序方式: 共有1021条查询结果,搜索用时 15 毫秒
1.
传统工艺加工阀体、活门时,对机床的性能要求较高,一般为数控镗床。介绍了一种采用普通镗床加工阀体、活门的工艺方法及蝶阀在厂内装配的工艺方法。 相似文献
2.
R. E. Uhrig 《Progress in Nuclear Energy》1995,29(3-4):357-370
The integrated use of neural network and noise analysis technologies offers advantages not available by the use of either technology alone. The application of neural network technology to noise analysis offers an opportunity to expand the scope of problems where noise analysis is useful and unique ways in which the integration of these technologies can be used productively. The two-sensor technique, in which the responses of two sensors to an unknown driving source are related, is used to demonstration such integration. The relationship between power spectral densities (PSDs) of accelerometer signals is derived theoretically using noise analysis to demonstrate its uniqueness. This relationship is modeled from experimental data using a neural network when the system is working properly, and the actual PSD of one sensor is compared with the PSD of that sensor predicted by the neural network using the PSD of the other sensor as an input. A significant deviation between the actual and predicted PSDs indicate that system is changing (i.e., failing). Experiments carried out on check valves and bearings illustrate the usefulness of the methodology developed. 相似文献
3.
通过引进型国产300MW汽轮机在启动试运中出现的一次窜轴事故,根据计算机追忆打印的有关图表、数据分析了产生事故的原因,并提出了为防止类似事故重演应采取的措施和建议。经采取措施后该机组多次又在相同情况下启机,已安全运行。说明分析正确,措施得当,值得同类型机组借鉴。 相似文献
4.
5.
张和青 《石油化工设备技术》1995,16(6):55-56
分析了润滑油加氢装置阀门产生泄漏的原因,针对存在的问题,提出了防止阀门泄漏的方法,确保了装置“两年一修”的长周期安全运行。 相似文献
6.
7.
8.
An improved bacterial foraging algorithm for combined static/dynamic environmental economic dispatch
Nicole Pandit Anshul Tripathi Shashikala Tapaswi Manjaree Pandit 《Applied Soft Computing》2012,12(11):3500-3513
Economic dispatch is carried out at the energy control center to find out the optimal output of thermal generating units such that power balance criterion is met, unit operating limits are satisfied and the fuel cost is minimized. With growing environmental awareness and strict government regulations throughout the world, it has become essential to optimize not only the total fuel cost but also the harmful emissions, both, under static as well as dynamic conditions. The static environment economic dispatch finds the optimal output of generating units for a fixed load demand at a given time, while the dynamic environmental economic dispatch schedules the output of online generators with changing power demands over a certain time period (normally one day) so as to minimize these two conflicting objectives, simultaneously. In this paper, the price penalty factor approach is employed for simultaneous minimization of cost and emission. The generator ramp rate constraints, non-convex and discontinuous nature of cost function and the large number of generators in practical power plants, make this problem very difficult to solve. Here, a fuzzy ranking approach is employed to identify the solution which offers the best compromise between cost and emission objectives. 相似文献
9.
10.
Valve trays are becoming popular in the chemical process industries owing to their flexibility to handle a wide range of vapor
throughputs. Using the rigorous rate based model, the importance of the non-equilibrium approach is demonstrated for a typical
extractive distillation process in a Glitsch V-1 valve tray column. Simulation results based on an in-house developed code
indicated that the rate based model predictions for a valve tray column operation showed significant differences relative
to the equilibrium model. Even small errors in product purities translated into nonoptimal feed stage locations and inaccurate
number of stages required. The counter-intuitive effect of high reflux ratio on separation is explained. 相似文献