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排序方式: 共有2234条查询结果,搜索用时 125 毫秒
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Kim Kihyeun Son Myungwoo Pak Yusin Chee Sang-Soo Auxilia Francis Malar Lee Byung-Kee Lee Sungeun Kang Sun Kil Lee Chaedeok Lee Jeong Soo Kim Ki Kang Jang Yun Hee Lee Byoung Hun Jung Gun-Young Ham Moon-Ho 《Nano Research》2018,11(7):3957-3957
Nano Research - The order of the authors in the original version of this article was unfortunately incorrect on the first page and the first page of the ESM. Instead of Myungwoo Son1, Yusin Pak1,... 相似文献
56.
Scanning laser range sensors provide range data consisting of a set of point measurements. The laser sensor URG-04LX has a
distance range of approximately 0.02–4 m and a scanning angle range of 240°. Usually, such an image range is acquired from
one viewpoint by “moving” the laser beam using rotating mirrors/prisms. The orientation of the laser beam can easily be measured
and converted into the coordinates of the image. This article conducts localization using virtual labels with data about distances
in the environment obtained from 2D distance laser sensors. This method puts virtual labels on special features and points
which are along the mobile robot’s path. The current location is calculated by combining the virtual label and the range image
of the laser range finder. 相似文献
57.
Abstract— High‐efficiency and simple‐structured red‐emitting phosphorescent devices based on the hole‐injection layer of 4,4′,4″‐tris(2‐naphthylphenyl‐phenylamino)‐triphenylamine [2‐TNATA] and the emissive layer of bis(10‐hydroxybenzo[h] quinolinato)beryllium complex [Bebq2] doped with SFC‐411 (proprietary red phosphorescent dye) have been researched. The fabricated devices are divided into three types depending on whether or not the hole‐transport layer of N,N′‐bis(1 ‐naphthyl)‐N, N'‐diphenyl‐1,1′‐biphenyl‐4,4′‐diamine [NPB] or the electron‐transport layer of SFC‐137 (proprietary electron transporting material) is included. Among the experimental devices, the best electroluminescent characteristics were obtained for the device with an emission structure of 2‐TNATA/Bebq2:SFC‐411/SFC‐137. In this device, current density and luminance were found to be 200 mA/cm2 and 15,000 cd/m2 at an applied voltage of 7 V, respectively. Current efficiencies were 15 and 11.6 cd/A under a luminance of 500 and 5000 cd/m2. The peak wavelength in the electroluminescent spectral distribution and color coordinates on the Commission Internationale de I'Eclairage (CIE) chart were 628 nm and (0.67, 0.33), respectively. 相似文献
58.
Sang‐Hee Ko Park Min‐Ki Ryu Sung‐Min Yoon Shinhyuk Yang Chi‐Sun Hwang Jae‐Hong Jeon 《Journal of the Society for Information Display》2010,18(10):779-788
Abstract— The stability of oxide TFTs has been the main focus of this research and is probably the most crucial requirement for the successful application to flat‐panel displays. Although the high Fermi level of oxide semiconductors makes TFTs basically stable under electrical stress, the device reliability under diverse variations of electrical stress is affected by materials such as active semiconductors and gate insulators, processes for the formation of back/front channels and passivation layers, and device configurations among other things. How these factors affect the device reliability have been investigated and a review of the stability is presented. In addition, several categories of the light instability of oxide TFTs is presented and the origin is discussed. 相似文献
59.
Comparison of forecasting methods with an application to predicting excess equity premium 总被引:2,自引:0,他引:2
This paper reviews various forecast methods including combination using theoretically optimal weights and those under model selection approaches. In addition, we suggest two modified simple averaging forecast combination methods—a mean corrected and a mean and scale corrected method. We conclude that due to the fact that real data is usually subject to structural breaks, rolling forecasting scheme has a better performance than fixed window and continuously updating scheme. In addition, methods that use less information appear to perform better than methods using all the sample information about the covariance structure of the available forecasts. The mean and scale corrected simple average approach yield smaller mean squared forecast error than the three widely used regression approaches suggested by Granger and Ramanathan [11]. 相似文献
60.
Joon-Chul?Lee Moon-Sun?Kim Chul?Kyung?Kim Chan-Hwa?Chung Sung?M.?Cho Gui?Young?Han Ki?June?Yoon Byung-Woo?KimEmail author 《Korean Journal of Chemical Engineering》2003,20(5):862-868
Experiments were performed to investigate the effect of operating parameters on the photodegradation efficiency of paraquat
in a TiO2-suspended photoreactor with immersed UV lamps. TiO2 particles were prepared by a hydrothermal method. The removal rate of paraquat in the reactor was 0.54 mg/l/h with only air-sparging.
The removal rate in 24 h with both the UV radiation and air-sparging was 50% higher than that with only the UV radiation.
Variations of the paraquat concentration at the UV intensities of 4 and 8 W/m2 decreased slowly with time, but that at 12 W/m2 decreased more rapidly. The removal efficiency at the air-sparging flow rate of 1 //min increased as a UV light intensity
increased. pH value in the reactor at the UV intensity of 12 W/m2 decreased with time until 12 h and then increased with time over 12 h. 相似文献