全文获取类型
收费全文 | 74篇 |
免费 | 5篇 |
专业分类
化学工业 | 11篇 |
机械仪表 | 8篇 |
建筑科学 | 2篇 |
能源动力 | 7篇 |
轻工业 | 1篇 |
无线电 | 29篇 |
一般工业技术 | 8篇 |
冶金工业 | 2篇 |
原子能技术 | 2篇 |
自动化技术 | 9篇 |
出版年
2023年 | 2篇 |
2022年 | 1篇 |
2021年 | 7篇 |
2020年 | 1篇 |
2018年 | 2篇 |
2017年 | 5篇 |
2016年 | 4篇 |
2015年 | 2篇 |
2014年 | 6篇 |
2013年 | 9篇 |
2012年 | 5篇 |
2011年 | 9篇 |
2010年 | 6篇 |
2009年 | 2篇 |
2008年 | 3篇 |
2007年 | 4篇 |
2006年 | 2篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 1篇 |
2001年 | 1篇 |
1999年 | 1篇 |
1993年 | 1篇 |
1986年 | 1篇 |
排序方式: 共有79条查询结果,搜索用时 15 毫秒
31.
32.
Dong-Seok KimTae-Hyeon Kim Chul-Ho WonHee-Sung Kang Ki-Won KimKi-Sik Im Yong Soo LeeSung-Ho Hahm Jung-Hee Lee Jae-Hoon LeeJong-Bong Ha Youngho BaeSorin Cristoloveanu 《Microelectronic Engineering》2011,88(7):1221-1224
We have grown high quality GaN layers on (1 1 1)-oriented silicon substrate using a two-step growth method and fabricated high-performance normally-off n-channel GaN Schottky-barrier MOSFET (SB-MOSFET). Indium-tin-oxide (ITO) was used as Schottky-barrier contact for source and drain (S/D) because the work function of ITO is close to the electron affinity of GaN. Due to enhanced crystalline quality and reduced surface roughness of GaN layer grown by two-step process, the fabricated device exhibited much improved performances: sufficiently high threshold voltage of 3.75 V, subthreshold slope of 171 mV/dec, low specific on-resistance of 9.98 mΩ cm2, and very high field-effect mobility of 271 cm2/V s. This is the highest mobility value among the GaN MOSFETs ever reported so far. 相似文献
33.
This study examines whether the New Electricity Market of Singapore (NEMS) is functioning at a workable level of competition. The generation market of the NEMS appears highly concentrated by a four-firm concentration ratio or the Herfindahl–Hirschman Index. However, other measures of market power present that the NEMS is working at close to a competitive market. First, there seems to be a number of effective competitors in the market. Second, Supply Margin Assessment and Residual Supply Index support that the market is competitive though there are some possibilities in which the largest generator or a few large generators jointly could still have market power. Third, the Lerner Index of the NEMS shows that the generation market is fairly competitive and the Lerner Index adjusted with an industry level price elasticity of demand implies that there has not been much exercise of market power. Finally, vesting contracts—a contractual obligation of a specified quantity of electricity supply to the market—have appeared to be a strong and effective tool to mitigate market power in the NEMS. The vesting contracts are considered the force behind the lowering in the average Uniform Singapore Electricity Price and the Lerner Index in 2004. 相似文献
34.
A fundamental study of bent pile structures subjected to combined loads in multi-layered soil is conducted using in situ load tests and a load transfer approach. The emphasis is on quantifying an improved design method developed by considering the pile’s plastic hinge and the column–pile interaction. An analytical model is developed that takes into account the nonlinear behaviour of materials for different soil–pile conditions. A framework for determining an optimized column–pile diameter ratio on basis of theoretical analysis is proposed through the relation between the column–pile diameter ratio and lateral crack load ratio. Based on the measured results, an optimized limit depth for a minimum steel reinforcement ratio is defined as the relationship between the bending moments and the crack moments of the concrete pile. An optimized limit depth for a minimum steel reinforcement ratio proportionally decreases as pile length increases, and beyond that the limit depth converges at a constant value (?0.3). 相似文献
35.
In this paper, we propose a non‐blind watermarking method that embeds a pseudo‐random sequence (watermarks) into wavelet DC components. The DC area is not suitable for embedding because of severe visual degradation. We overcome the degradation problem by embedding watermarks into visually insensitive locations. We compare our experimental results with respect to JPEG compression with Cox's popular correlation‐based method. We also compare the robustness of our technique with other methods registered in CheckMark. This study reveals that the proposed method simultaneously provides good fidelity in quality as well as robustness against external attacks 相似文献
36.
37.
Youngho Kang 《Journal of the American Ceramic Society》2022,105(9):5807-5816
Although lead halide perovskites (LHPs) have emerged as interesting photovoltaic (PV) absorbers for thin-film solar cells, the toxicity of Pb and poor materials stability have hindered the commercialization of solar cells using LHPs. Herein, using density functional theory (DFT) calculations, we suggest antiperovskite nitrides Sr3MN and Ba3MN (M = Sb or Bi) as potential Pb-free PV absorbers for thin-film solar cells. State-of-the-art DFT calculations based on the GW approximation show that these compounds have direct bandgaps suitable for PV applications. In addition, they exhibit significant absorption coefficients over 105 cm−1 for the visible light. By calculating spectroscopic limited maximum efficiency, we demonstrate that the film thicknesses of several hundred nanometers are enough for Sr3MN and Ba3MN to generate high-power conversion efficiencies over 20%. The analysis of the electron and hole effective masses reveals that these compounds have efficient carrier-diffusion paths allowing for the facile extraction of photocarriers. Lastly, we investigate the band alignments of the materials to help the design of thin-film solar cells. 相似文献
38.
Bumsuk Choi Jeonghak Kim Soonchoul Kim Youngho Jeong Jin Woo Hong Won Don Lee 《ETRI Journal》2013,35(2):292-300
Augmented reality (AR) is a popular service in mobile devices, and many AR applications can be downloaded from app stores. As TV broadcasting has continued to integrate with the Internet, it has become an area in which the AR concept is able to reside, although in a simple form, such as an advertisement placed in the static region of a scene. There are some restrictions against TV broadcasting realizing AR since TVs are fixed devices and typically do not have GPS, geomagnetic, or acceleration sensors, which are standard equipment in mobile devices. However, the desire to experience AR on a large TV screen has triggered research and development for an ideal AR business model and service type. This paper introduces several use cases for augmented broadcasting services and also presents an augmented broadcasting metadata scheme designed for a broadcasting environment. We also verify some of the use cases and an augmented broadcasting metadata scheme in an implemented augmented broadcasting system based on a hybrid TV platform. 相似文献
39.
40.
Photoreceptors: Artificial Rod and Cone Photoreceptors with Human‐Like Spectral Sensitivities (Adv. Mater. 27/2018)
下载免费PDF全文
![点击此处可从《Advanced materials (Deerfield Beach, Fla.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Byeongho Park Heehong Yang Tai Hwan Ha Hyun Seo Park Seung Ja Oh Yong‐Sang Ryu Youngho Cho Hyo‐Suk Kim Juyeong Oh Dong Kyu Lee Chulki Kim Taikjin Lee Minah Seo Jaebin Choi Young Min Jhon Deok Ha Woo Seok Lee Seok Hwan Kim Hyuk‐Jae Lee Seong Chan Jun Hyun Seok Song Tai Hyun Park Jae Hun Kim 《Advanced materials (Deerfield Beach, Fla.)》2018,30(27)