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排序方式: 共有303条查询结果,搜索用时 31 毫秒
1.
Jeon Ok Sung Park Myeong Geun Song Rak Hyun Ryu Kwang Hyun Na Chan Woong Shul Yong Gun Lee Jin Goo 《Journal of Materials Science: Materials in Electronics》2022,33(6):3208-3214
Journal of Materials Science: Materials in Electronics - The effects of doping a trace of Fe2O3 on the structural and electrical properties of 8 mol% yttria-stabilized zirconia (8YSZ) are... 相似文献
2.
Seung‐Hyun Kim Victoria Hwang Sang Goo Lee Jong‐Wook Ha Vinothan N. Manoharan Gi‐Ra Yi 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(23)
Hollow carbon–silica nanospheres that exhibit angle‐independent structural color with high saturation and minimal absorption are made. Through scattering calculations, it is shown that the structural color arises from Mie resonances that are tuned precisely by varying the thickness of the shells. Since the color does not depend on the spatial arrangement of the particles, the coloration is angle independent and vibrant in powders and liquid suspensions. These properties make hollow carbon–silica nanospheres ideal for applications, and their potential in making flexible, angle‐independent films and 3D printed films is explored. 相似文献
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Identification and extraction of brain tumor from MRI using local statistics of Zernike moments 下载免费PDF全文
Kiran Thapaliya Goo‐Rak Kwon 《International journal of imaging systems and technology》2014,24(4):284-292
In this article, a novel method is proposed for the detection of brain tumor in magnetic resonance images (MRIs). The features of Zernike moments are used to analyze the MRIs. The image is divided into two parts from the center of the image based on the average value of the pixel located at the center boundary, and new image vectors are formed to extract the tumor. The local statistics values obtained from the low and high order Zernike moments are used to calculate the appropriate threshold value for efficient tumor extraction. The proposed method successfully analyzes the tumor part of the image on testing with different MRIs. 相似文献
6.
Sang Goo Jeon Jeong-Geol Na Chang Hyun KoKi Bong Lee Nam Sun RhoSeung Bin Park 《Materials Science and Engineering: B》2011,176(7):606-610
A new route via the coating of layered ammonium nickel molybdate with oleic acid was developed to prepare an oil-soluble bimetallic dispersed catalyst for the hydrocracking reaction of heavy oil. The layered ammonium nickel molybdate, termed Ni-LTM precursor, was synthesized by precipitation, and the NiMo oleate complex was prepared with the oleic acid serving as an organic ligand. The prepared materials were characterized with X-ray diffraction, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. It was found that the oleic acid is chemisorbed as a carboxylate onto the Ni-LTM nanoparticles, specifically on Ni-O bond. Also, the catalytic activities were compared between the NiMo oleate complex and other ordinary monometallic dispersed catalysts. The NiMo oleate complex showed excellent catalytic activity, demonstrating its potential to be applied as a novel dispersed catalyst. 相似文献
7.
“Multipoint Force Feedback” Leveling of Massively Parallel Tip Arrays in Scanning Probe Lithography 下载免费PDF全文
Hanaul Noh Goo‐Eun Jung Sukhyun Kim Seong‐Hun Yun Ahjin Jo Se‐Jong Kahng Nam‐Joon Cho Sang‐Joon Cho 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(35):4526-4531
Nanoscale patterning with massively parallel 2D array tips is of significant interest in scanning probe lithography. A challenging task for tip‐based large area nanolithography is maintaining parallel tip arrays at the same contact point with a sample substrate in order to pattern a uniform array. Here, polymer pen lithography is demonstrated with a novel leveling method to account for the magnitude and direction of the total applied force of tip arrays by a multipoint force sensing structure integrated into the tip holder. This high‐precision approach results in a 0.001° slope of feature edge length variation over 1 cm wide tip arrays. The position sensitive leveling operates in a fully automated manner and is applicable to recently developed scanning probe lithography techniques of various kinds which can enable “desktop nanofabrication.” 相似文献
8.
Md. Dulal Hossain Junghoon Moon Hyoung Goo Kang Sung Chul Lee Young Chan Choe 《Scientometrics》2012,90(1):57-83
Triple helix (TH) collaborations involving university, industry and government provide a networked infrastructure for shaping
the dynamic fluxes of knowledge base of innovations locally and these fluxes remain emergent within the domains. This study
maps these emergence dynamics of the knowledge base of innovations of Research & Development (R&D) by exploring the longitudinal
trend of systemness within the networked research relations in Bangladesh on the TH model. The bibliometric data of publications
collected from the Science Citation Index (SCI), the social sciences and the arts and humanities for analysis of science indicators
and the patent data collected from the US Patent Office to analyze the patent success ratio as a measure of innovation within
TH domains. The findings show that the network dynamics have varied considerably according to the R&D policies of the government.
The collaboration patterns of co-authorship relations in the SCI publications prominently increased, with some variation,
from 1996 to 2006. Nevertheless, inter-institutional collaboration negatively influenced by the national science and technology
(S&T) research policies in the last 5 years due to their evaluation criteria. Finally, the findings reveal that the R&D system
of Bangladesh is still undergoing a process of institutionalizing S&T and has failed to boost its research capacity for building
the knowledge base of innovations by neglecting the network effects of TH dynamics. 相似文献
9.
Sang Jun Yoon Jae Goo Lee Hideo Tajima Akihiro Yamasaki Fumio Kiyono Tetsuya Nakazato Hiroaki Tao 《Journal of Industrial and Engineering Chemistry》2010,16(3):350-354
Extractions of five kinds of lanthanide metal ions by bis(2-ethylhexyl)phosphoric acid (DEHPA) with [1-Cn-3-methylimidazolium][PF6](Cn = C2, C4) or [1-butyl-4-methylpyridinium][PF6] were carried out under various DEHPA and HNO3 concentrations from 0 to 1 M and under different temperature conditions from 298 to 333 K. These results were compared with those using the conventional organic solvent, hexane, in terms of their distribution coefficient values. Under all of the conditions in this study, the ionic liquid system shows more than three times greater extractability for lanthanide compared to when hexane was used. The distribution coefficient of lanthanide ions decreased as the length of the alkyl chain increased from the ethyl to the butyl. In addition, the imidazolium cation generally shows a higher distribution coefficient compared to the pyridinium cation in an ionic liquid. The concentration ratio of lanthanides and DEHPA resulted in an extraction affinity transition for lanthanides. Also evaluated in this study were issues related to the selectivity associated with the lanthanide mixture and the dependency of the ionic radius during lanthanide extraction. 相似文献
10.
Goo Yeon Lee Yong Lee 《Communications Letters, IEEE》2002,6(10):431-433
In this letter, we analyze a time-based update method in location management and calculate the optimal time-interval. We obtain the probability that a mobile terminal (MT) is j rings away from the center cell. And using these values, an exact analysis is made for the time-based location management cost. From the result, when the time-based method is applied to location update, we can get the optimal time-interval which minimizes the location management cost 相似文献