全文获取类型
收费全文 | 455篇 |
免费 | 14篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 156篇 |
金属工艺 | 7篇 |
机械仪表 | 17篇 |
建筑科学 | 7篇 |
矿业工程 | 1篇 |
能源动力 | 10篇 |
轻工业 | 19篇 |
水利工程 | 2篇 |
无线电 | 46篇 |
一般工业技术 | 107篇 |
冶金工业 | 27篇 |
原子能技术 | 6篇 |
自动化技术 | 63篇 |
出版年
2023年 | 1篇 |
2022年 | 8篇 |
2021年 | 22篇 |
2020年 | 9篇 |
2019年 | 6篇 |
2018年 | 9篇 |
2017年 | 10篇 |
2016年 | 19篇 |
2015年 | 15篇 |
2014年 | 23篇 |
2013年 | 36篇 |
2012年 | 29篇 |
2011年 | 30篇 |
2010年 | 22篇 |
2009年 | 20篇 |
2008年 | 21篇 |
2007年 | 30篇 |
2006年 | 12篇 |
2005年 | 24篇 |
2004年 | 5篇 |
2003年 | 9篇 |
2002年 | 10篇 |
2001年 | 3篇 |
2000年 | 7篇 |
1999年 | 4篇 |
1998年 | 6篇 |
1997年 | 5篇 |
1996年 | 6篇 |
1995年 | 7篇 |
1994年 | 7篇 |
1993年 | 4篇 |
1992年 | 5篇 |
1991年 | 7篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 6篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 7篇 |
1980年 | 1篇 |
1979年 | 4篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1973年 | 1篇 |
1971年 | 2篇 |
1967年 | 1篇 |
排序方式: 共有469条查询结果,搜索用时 140 毫秒
101.
Mode selection schemes for unicasting device‐to‐device communications supported by network coding
下载免费PDF全文
![点击此处可从《International Journal of Communication Systems》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Device‐to‐device (D2D) communication in a cellular spectrum increases the spectral and energy efficiency of local communication sessions, while also taking advantage of accessing licensed spectrum and higher transmit power levels than when using unlicensed bands. To realize the potential benefits of D2D communications, appropriate mode selection algorithms that select between the cellular and D2D communication modes must be designed. On the other hand, physical‐layer network coding (NWC) at a cellular base station—which can be used without D2D capability—can also improve the spectral efficiency of a cellular network that carries local traffic. In this paper, we ask whether cellular networks should support D2D communications, physical‐layer NWC, or both. To this end, we study the performance of mode selection algorithms that can be used in cellular networks that use physical‐layer NWC and support D2D communications. We find that the joint application of D2D communication and NWC scheme yields additional gains compared with a network that implements only one of these schemes, provided that the network implements proper mode selection and resource allocation algorithms. We propose 2 mode selection schemes that aim to achieve high signal‐to‐interference‐plus‐noise ratio and spectral efficiency, respectively, and take into account the NWC and D2D capabilities of the network. 相似文献
102.
Journal of Computer and Systems Sciences International - The problem of designing a control law that guarantees the asymptotical stability of a moving object in a neighborhood of an instable... 相似文献
103.
104.
In this paper, a high resolution and wideband incremental ADC with extended counting is described and analyzed. The modulator introduced inter-stage gain to reduce the quantization noise without adding any hardware. Also, a gain scaling technique was used to decrease the power consumption by reducing the integrators’ output swing. First, the 2nd order incremental ΔΣ ADC and 11-bit SAR ADC were measured separately. Second, the incremental ΔΣ ADC with extended counting was tested. It achieved a 91.6 dB dynamic range and 77.8 dB SNDR in the 0–1.25 MHz signal band. The total power consumption is 53.5 mW with dual power supplies (analog 3.3 V, digital 1.8 V). 相似文献
105.
Emese Abram Gabor Gajdatsy Peter Hermann Ferenc Ujhelyi Judit Borbely James Zhijian Shen 《应用陶瓷进展》2019,118(1-2):3-8
ABSTRACTObjective: The aim of this in vitro study is to examine the optical effects of monolithic zirconia of different translucency and thickness, combined with substrates of different colours. Materials and methods: Zirconia specimens of two colours (A2P1, WHITE) were used for the study, three try-in pastes (Variolink Esthetic); substrates were prepared from nine types of materials (six VITA SIMULATE, three metals). Measurements were carried out at the Faculty of Atomic Physics of the Technical University of Budapest with the state-of-the-art PerkinElmer® Lambda 1050 spectrophotometer. Results: The colouring of zirconia has a major effect on dE values resulting in different colour perceptibility and acceptability. Try-in pastes, however, have no significant effects overall. Conclusion: Applying coloured zirconia is highly eligible for preparing aesthetic crowns as their substrate-covering effect makes it possible to reproduce the desired colour. Uncoloured zirconia nonetheless is unaffected by the substrate material, especially above a certain layer thickness. 相似文献
106.
Tihamer Levendovszky Daniel Balasubramanian Anantha Narayanan Feng Shi Chris van Buskirk Gabor Karsai 《Software and Systems Modeling》2014,13(2):807-823
One of the main advantages of defining a domain-specific modeling language (DSML) is the flexibility to adjust the language definition to changing requirements or in response to a deeper understanding of the domain. With the industrial applications of domain-specific modeling environments, models are valuable investments. If the modeling language evolves, these models must be seamlessly migrated to the evolved DSML. Although the changes stemming from the language evolution are not abrupt in nature, migrating existing models to a new language is still a challenging task. Our solution is the Model Change Language (MCL) tool set, which defines a DSML to describe the migration rules and then performs the model migration automatically. In this paper, we describe the precise semantics of MCL and its execution, along with the confluence of the migration. 相似文献
107.
Gabor C Back JJ Faircloth DC Izaola Z Lawrie SR Letchford AP 《The Review of scientific instruments》2012,83(2):02B719
The Front End Test Stand (FETS) is located at Rutherford Appleton Laboratory and aims for a high current, fast chopped 3 MeV H(-) ion beam suitable for future high power proton accelerators like ISIS upgrade. The main components of the front end are the Penning ion source, a low energy beam transport line, an radio-frequency quadrupole (RFQ) and a medium energy beam transport (MEBT) providing also a chopper section and rebuncher. FETS is in the stage of commissioning its low energy beam transport (LEBT) line consisting of three solenoids. The LEBT has to transport an H(-) high current beam (up to 60 mA) at 65 keV. This is the injection energy of the beam into the RFQ. The main diagnostics are slit-slit emittance scanners for each transversal plane. For optimizing the matching to the RFQ, experiments have been performed with a variety of solenoid settings to better understand the actual beam transport. Occasionally, source parameters such as extractor slit width and beam energy were varied as well. The paper also discusses simulations based on these measurements. 相似文献
108.
Pajor G Alpar D Kajtar B Melegh B Somogyi L Kneif M Bollmann D Pajor L Sule N 《Microscopy research and technique》2012,75(6):814-820
OBJECTIVE: Signal pattern enumeration of Urovysion Fluorescence in Situ Hybridization test is tedious and requires great experience. Our aim was to eliminate human interaction by automating the process, using an adoptable, automated image acquisition, and analysis system. METHODS: For extensive analytical analysis control, cell populations were used, while preliminary clinical study was performed on 21 patients with clinical suspicion for bladder cancer. All investigations were carried out using an automated user‐trainable workstation (Metafer4‐Metacyte). RESULTS: The system identified nuclei with a specificity and sensitivity of 92.7 and 96.6%, respectively, while signal detection accuracy was 81.1% on average. Both analytical and diagnostic accuracy of automated analysis was comparable to manual approach (94.8 and 71% vs. 97.9 and 76%, respectively), but classification accuracy increased with degree of polysomy, thus diagnostic sensitivity in low grade, low stage cases was poor. CONCLUSION: It is possible to automate signal enumeration of Urovysion using a user‐trainable system, and achieve efficiency comparable to manual analysis. Previously introduced automated immunophenotypic targeting should further increase diagnostic sensitivity, while resulting in a comprehensively automated method. However, the problem of reduced detection accuracy in cases featured with low polysomy is likely to remain a great challenge of automated signal enumeration. Microsc. Res. Tech. 75:814–820, 2012. © 2011 Wiley Periodicals, Inc. 相似文献
109.
110.