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排序方式: 共有1908条查询结果,搜索用时 15 毫秒
31.
1 INTRODUCTION Since Cu-ZSM-5 was reported as an effective catalyst for the selective catalytic reduction (SCR) of NO by hydrocarbons in the presence of excess oxygen, the SCR of NOx has received much attention as a kind of potential technology for cleaning NOx in various oxygen-rich exhausts of diesel engine, lean burning gasoline engine and gas engine. Although a number of catalysts have been tested, to date, it still seems to be difficult to find a catalyst that is completely suit… 相似文献
32.
Zilu Liang Bernd Ploderer Wanyu Liu Yukiko Nagata James Bailey Lars Kulik Yuxuan Li 《Personal and Ubiquitous Computing》2016,20(6):985-1000
Getting enough quality sleep is a key part of a healthy lifestyle. Many people are tracking their sleep through mobile and wearable technology, together with contextual information that may influence sleep quality, like exercise, diet, and stress. However, there is limited support to help people make sense of this wealth of data, i.e., to explore the relationship between sleep data and contextual data. We strive to bridge this gap between sleep-tracking and sense-making through the design of SleepExplorer, a web-based tool that helps individuals understand sleep quality through multi-dimensional sleep structure and explore correlations between sleep data and contextual information. Based on a two-week field study with 12 participants, this paper offers a rich understanding on how technology can support sense-making on personal sleep data: SleepExplorer organizes a flux of sleep data into sleep structure, guides sleep-tracking activities, highlights connections between sleep and contributing factors, and supports individuals in taking actions. We discuss challenges and opportunities to inform the work of researchers and designers creating data-driven health and well-being applications. 相似文献
33.
34.
Okano D 《The Review of scientific instruments》2011,82(12):123502
For atmospheric streamer discharges using a lightning impulse generator, we demonstrate a method of determining the plasma impedance in a streamer region by analyzing the periodic attenuated discharge waveforms having high-frequency components. When the streamer region in the plasma can be treated as an equivalent series circuit model including resistance and inductance elements, the regression waveforms obtained by reducing and smoothing the discharge waveforms are analyzed in the equivalent circuit. We found that the streamer resistance increased exponentially with time after the discharge, whereas the streamer inductance and series impedance were constant at 4.0 Ω for longer than the first period of the discharge waveforms. Moreover, the slope of the regression curve increases more rapidly for the positive streamer resistance than for the negative resistance. Finally, the absolute values of the streamer impedance versus time were 3.3-19 Ω and 3.5-9.0 Ω for positive and negative discharges, respectively. 相似文献
35.
36.
Oliver Bimber Daisuke Iwai Gordon Wetzstein Anselm Grundhöfer 《Computer Graphics Forum》2008,27(8):2219-2245
This article focuses on real‐time image correction techniques that enable projector‐camera systems to display images onto screens that are not optimized for projections, such as geometrically complex, coloured and textured surfaces. It reviews hardware‐accelerated methods like pixel‐precise geometric warping, radiometric compensation, multi‐focal projection and the correction of general light modulation effects. Online and offline calibration as well as invisible coding methods are explained. Novel attempts in super‐resolution, high‐dynamic range and high‐speed projection are discussed. These techniques open a variety of new applications for projection displays. Some of them will also be presented in this report. 相似文献
37.
Kenichi Mori Michiaki Sakamoto Jin Matsushima Daisuke Inoue Kenichirou Naka Ken Sumiyoshi 《Journal of the Society for Information Display》2009,17(6):513-518
Abstract— In order to improve the reflective contrast ratio of transflective IPS‐LCDs, a novel pixel design for a normally white reflective IPS has been proposed. In this design, the large‐inter‐electrode‐spacing layout using a novel driving method and a double‐layered electrode have effectively reduced the light leakage. By applying these two technologies, a transflective IPS‐LCD has been successfully demonstrated with a high contrast ratio (15:1) in the reflective mode and a wide‐viewing‐angle characteristic in the transmissive mode. 相似文献
38.
Correlation between Chemical Dopants and Topological Defects in Catalytically Active Nanoporous Graphene
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39.
K Ozaki M Nagata M Suzuki T Fujiwara Y Miyoshi O Ishikawa H Ohigashi S Imaoka E Takahashi Y Nakamura 《Canadian Metallurgical Quarterly》1998,22(3):179-185
We reviewed 19 children and adolescents with cervical spine congenital synostosis as in Klippel-Feil syndrome (KFS), with an average follow-up of 12.5 years. We paid particular attention to neurologic complications associated with cervical spine abnormalities. Five patients were affected by neurologic complications; four underwent a surgical procedure; and 14 had no neurologic finding. Two had hypermobility at one level, and one had hypermobility at two levels. We found that the more numerous the occipito-C1 abnormalities, the more significant the neurologic risk. In contrast, this risk was not related to the number of "mobile blocks" or to age. Various mechanisms of neural complications have been studied in the literature: medullary abnormality, spinal instability, narrowing of the cervical canal, and vascular dysfunction. Surgery is usually thought to be required in cases with neurologic complications. The indication for surgery is, however, less clear in cases of pure instability without neurologic involvement because surgery is likely to increase the future risks at mobile disks either above or below the fuse level. Careful clinical and radiologic observation is necessary in such patients. Magnetic resonance imaging (MRI) with lateral views in flexion and extension seem to be the best method for detecting impingement of the spine on the cord. 相似文献
40.
Kazushi Yawata Daisuke Ito Hiroki Ikegami Hidehiko Ishimoto Hiroshi Fukuyama 《Journal of Low Temperature Physics》1998,113(5-6):769-774
Experimental methods and preliminary results of high-precision measurements of the
3
He melting curve in high magnetic fields have been described. The purpose of this work is twofold. One is to establish a reliable millikelvin temperature scale in high fields (T 10 mK, B 15 T), The other is to investigate a high field region of the magnetic phase diagram of solid
3
He by measuring the melting pressure down to temperatures below 1 mK. Besides the two superfluid transitions, the phase transition temperatures between the spin ordered solid and the paramagnetic solid, T
HFP
, were determined at B = 12 and 10 T with good accuracy, which is an extension of previous measurements up to 8 T. The present T
HFP
(B) line can not be scaled to that at a higher density with a single Grüneisen parameter, indicating a variation of density dependencies of the multiple-spin exchange interactions. 相似文献