全文获取类型
收费全文 | 1586篇 |
免费 | 64篇 |
国内免费 | 10篇 |
专业分类
电工技术 | 23篇 |
综合类 | 4篇 |
化学工业 | 285篇 |
金属工艺 | 85篇 |
机械仪表 | 65篇 |
建筑科学 | 39篇 |
能源动力 | 66篇 |
轻工业 | 82篇 |
水利工程 | 5篇 |
石油天然气 | 1篇 |
无线电 | 271篇 |
一般工业技术 | 327篇 |
冶金工业 | 157篇 |
原子能技术 | 12篇 |
自动化技术 | 238篇 |
出版年
2023年 | 32篇 |
2022年 | 37篇 |
2021年 | 62篇 |
2020年 | 68篇 |
2019年 | 61篇 |
2018年 | 75篇 |
2017年 | 69篇 |
2016年 | 41篇 |
2015年 | 27篇 |
2014年 | 71篇 |
2013年 | 103篇 |
2012年 | 74篇 |
2011年 | 84篇 |
2010年 | 54篇 |
2009年 | 77篇 |
2008年 | 69篇 |
2007年 | 48篇 |
2006年 | 53篇 |
2005年 | 50篇 |
2004年 | 46篇 |
2003年 | 42篇 |
2002年 | 32篇 |
2001年 | 22篇 |
2000年 | 19篇 |
1999年 | 23篇 |
1998年 | 30篇 |
1997年 | 39篇 |
1996年 | 30篇 |
1995年 | 26篇 |
1994年 | 18篇 |
1993年 | 16篇 |
1992年 | 17篇 |
1991年 | 15篇 |
1990年 | 17篇 |
1989年 | 18篇 |
1988年 | 8篇 |
1987年 | 11篇 |
1986年 | 5篇 |
1985年 | 9篇 |
1984年 | 3篇 |
1983年 | 8篇 |
1981年 | 5篇 |
1980年 | 5篇 |
1979年 | 6篇 |
1978年 | 4篇 |
1977年 | 5篇 |
1976年 | 4篇 |
1972年 | 3篇 |
1967年 | 3篇 |
1965年 | 3篇 |
排序方式: 共有1660条查询结果,搜索用时 15 毫秒
1.
2.
3.
Hsu S. Alvandpour A. Mathew S. Shih-Lien Lu Krishnamurthy R.K. Borkar S. 《Solid-State Circuits, IEEE Journal of》2003,38(5):755-761
This paper describes a 32-KB two-read, one-write ported L0 cache for 4.5-GHz operation in 1.2-V 130-nm dual-V/sub TH/ CMOS technology. The local bitline uses a leakage-tolerant self reverse-bias (SRB) scheme with nMOS source-follower pullup access transistors, while preserving robust full-swing operation. Gate-source underdrive of -220 mV on the bitline read-select transistors is established without external bias voltages or gate-oxide overstress. Device-level measurements in the 130-nm technology show 72/spl times/ bitline active leakage reduction, enabling low-V/sub TH/ usage, 40% bitline keeper downsizing, and 16 bitcells/bitline. 11% faster read delay and 2/spl times/ higher dc noise robustness are achieved compared with high-performance dual-V/sub TH/ bitline scheme. Sustained performance and robustness benefits of the SRB technique against conventional dynamic bitline with scaling to 100- and 70-nm technology is also presented. 相似文献
4.
Product mix determination in the presence of alternate process plans and stochastic demand 总被引:3,自引:0,他引:3
Raja G. Kasilingam 《Computers & Industrial Engineering》1995,29(1-4):249-253
The product mix problem in the presence of alternate process plans under uncertain demand is formulated as a non-linear programming model. A heuristic solution procedure based on lagrangean relaxation technique is also presented. 相似文献
5.
Response surface methodology is often used by researchers in different fields to determine the optimum values for controlled variables to maximize or minimize the response variables. Either maximization or minimization might be necessary depending on the response property. For example, if the response variable represents the yield of a process, maximization could be necessary; on the other hand, if the response variable is the biological oxygen demand (BOD) of an effluent the aim would definitely be minimization
Response surface methodology can be used two ways. It can be applied to the full-scale production or it can be scaled to a laboratory or the pilot plant. When applied to the full-scale production, the method is known as evolutionary operation (EVOP). EVOP is the continuous optimization of a process. The optimum conditions in a production plant can change depending on many factors such as raw material, ambient temperature, and equipment wear. Therefore, controlled variables should be optimized continuously to keep the response variable as close as possible to the maximum or minimum value. Hence, controlled variables are systematically changed around a center point to depict any shift of the response variable from the extreme. A thorough discussion of EVOP is given by Box, Evolutionary Operation: A Method for Increasing Industrial Productivity, Appl. Statist., 6, 81-101 (1957). 相似文献
Response surface methodology can be used two ways. It can be applied to the full-scale production or it can be scaled to a laboratory or the pilot plant. When applied to the full-scale production, the method is known as evolutionary operation (EVOP). EVOP is the continuous optimization of a process. The optimum conditions in a production plant can change depending on many factors such as raw material, ambient temperature, and equipment wear. Therefore, controlled variables should be optimized continuously to keep the response variable as close as possible to the maximum or minimum value. Hence, controlled variables are systematically changed around a center point to depict any shift of the response variable from the extreme. A thorough discussion of EVOP is given by Box, Evolutionary Operation: A Method for Increasing Industrial Productivity, Appl. Statist., 6, 81-101 (1957). 相似文献
6.
We investigate the transverse modal properties of cylindrical subwavelength metal-clad nanowire and micropost lasers via rigorous theoretical waveguide analysis, including the effects of finite thickness metal cladding and gain in the core. The results of this analysis show that air-metal surface guided TM01 and some hybrid surface guided modes suffer less loss but are less confined to the core, while core-metal surface guided modes are better confined to the core but suffer greater loss. An increase in the thickness of the metal cladding reduces the loss of the core-metal surface guided modes. The modal gain and confinement of the metal-clad cavity are compared to an unclad cavity. 相似文献
7.
The aqueous leaf extracts of five different deciduous plants, namely, silver oak, flame of the forest, tanner’s senna, wattle and serviceberry, were used on their own and in combination with aluminium sulphate, stannous chloride and ferrous sulphate to dye wool by a simultaneous mordanting technique. The washing and light fastness properties of the developed shades were moderate to good. Based on the CIE 2000 spectral colour coordinate values (K/S, ΔL, Δa, Δb and ΔE), the developed shades were classified into four groups: yellow/brown, yellow, orange and dark grey. The use of aluminium sulphate gave medium shades (K/S = 8.24), while the stannous chloride and ferrous sulphate mordants provided deep shades (K/S = 30.5). Statistical analyses have shown that only the type of mordant and not the dye source significantly influenced the development of colour on wool. Hence, it was theoretically possible to use five selected leaves as a single mixture to produce four different colours on wool. 相似文献
8.
Unconstrained and constrained motion control of a planar two-link structurally-flexible robotic manipulator are considered in this study. The dynamic model is obtained by using the extended Hamilton's principle and the Galerkin criterion. A method is presented to obtain the linearized equations of motion in Cartesian space for use in designing the control system. The approach to solving the control problem is to use feedforward and feedback control torques. The feedforward torques maneuver the flexible manipulator along a nominal trajectory and the feedback torques minimize any deviations from the nominal trajectory. The feedforward and feedback torques are obtained by solving the inverse dynamics problem for the rigid manipulator and designing linear quadratic Gaussian with loop transfer recovery (LQG/LTR) compensators, respectively. The LQG/LTR design methodology is exploited to design a robust feedback control system that can handle modeling errors and sensor noise, and operate on Cartesian space trajectory errors. Computer simulated results are presented for an example planar, two-link, structurally flexible robotic manipulator. © 1994 John Wiley & Sons, Inc. 相似文献
9.
Khan Muhammad Umer Arif Shukla Sanjay Kumar Raja Muhammad Nouman Amjad 《Neural computing & applications》2021,33(21):14861-14885
Neural Computing and Applications - Marston’s load theory is commonly used for understanding the soil–conduit interaction. However, there are no practical methods available which can... 相似文献
10.
The oxide films formed during early stage of oxidation at 800 °C on dendritic and interdendritic regions of the cast Fe–16Al–1C (wt.%) alloy were studied using scanning Auger electron spectroscopy. Microhardness measurement and elemental depth profiles by Auger spectroscopy reveal that the carbide, Fe3AlC0.69, is the major constituent of the interdendritic region, while dendrites are predominantly Fe3Al phase. Between the two, the interdendritic region is found to be more prone to oxidation than the dendritic region, which was attributed to presence of carbides with low-Al content. In spite of the difference in oxide film thickness exhibited by both the phases, they consist of an inner aluminium oxide layer and an outer iron oxide layer. 相似文献