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11.
Youngha Kim Sungkwan Kim Young-Ah Jeon Yunseok Kim Hanjong Paik Yangsoo Kim Sang-Chul Han Young-Hee Han Nyeon-Ho Jeong Tae-Hyun Sung Jong-In Hong Kwangsoo No 《Journal of Electroceramics》2006,17(2-4):1063-1067
YBa2Cu3Ox (Y123) superconducting films were fabricated on Cu substrates using a simple screen-printing method, from Cu-free powders
(Y2O3 and BaCO3). In the process, CuO, which causes superconducting properties of Y123 films to deteriorate, was formed on the film surface.
By varying the atomic ratio of Y to Ba (Y:Ba = 1:1∼1:4), the ratio needed to prevent CuO formation was found for the film
surface that had been heat-treated at 980∘C for 17 s. The film, with the ratio of Y to Ba (Y:Ba = 1:1), is reheat-treated at 930∘C for 9 min 30 s to form a superconducting Y123 phase. It was possible to prevent CuO formation by controlling the ratio of
Cu-free powders in the mixture and to fabricate YBCO superconductors on Cu substrates using a two-step heat-treatment. 相似文献
12.
Point fingerprint: a new 3-D object representation scheme 总被引:1,自引:0,他引:1
Yiyong Sun Joonki Paik Koschan A. Page D.L. Abidi M.A. 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2003,33(4):712-717
This paper proposes a new, efficient surface representation method for surface matching. A feature carrier for a surface point, which is a set of two-dimensional (2-D) contours that are the projections of geodesic circles on the tangent plane, is generated. The carrier is named point fingerprint because its pattern is similar to human fingerprints and plays a role in discriminating surface points. Corresponding points on surfaces from different views are found by comparing their fingerprints. The point fingerprint is able to carry curvature, color, and other information which can improve matching accuracy, and the matching process is faster than 2-D image comparison. A novel candidate point selection method based on the fingerprint irregularity is introduced. Point fingerprint is successfully applied to pose estimation of real range data. 相似文献
13.
Kim DJ Lee KB Lee TG Shon HK Kim WJ Paik HJ Choi IS 《Small (Weinheim an der Bergstrasse, Germany)》2005,1(10):992-996
Micropatterns of silica on a gold substrate were generated by a biomimetic approach, namely, the biosilicification of silicic acids. The procedure consists of three simple steps: pattern generation of a polymerization initiator, (BrC(CH(3))(2)COO(CH(2))(11)S)(2), by microcontact printing; surface-initiated, atom-transfer radical polymerization of 2-(dimethylamino)ethyl methacrylate (DMAEMA) from the patterned area; and polycondensation of silicic acids. The tertiary amine-containing polymer, pDMAEMA, aided in the spatially controlled polycondensation of silicic acids on surfaces in the presence of phosphate ions, and micropatterns of silica on a gold substrate were successfully generated in combination with the technique of microcontact printing. The procedure could be extended to the controlled fabrication of silica patterns with any size, shape, or thickness. 相似文献
14.
Gait recognition using active shape model and motion prediction 总被引:1,自引:0,他引:1
This study presents a novel, robust gait recognition algorithm for human identification from a sequence of segmented noisy silhouettes in a low-resolution video. The proposed recognition algorithm enables automatic human recognition from model-based gait cycle extraction based on the prediction-based hierarchical active shape model (ASM). The proposed algorithm overcomes drawbacks of existing works by extracting a set of relative model parameters instead of directly analysing the gait pattern. The feature extraction function in the proposed algorithm consists of motion detection, object region detection and ASM, which alleviate problems in the baseline algorithm such as background generation, shadow removal and higher recognition rate. Performance of the proposed algorithm has been evaluated by using the HumanID Gait Challenge data set, which is the largest gait benchmarking data set with 122 objects with different realistic parameters including viewpoint, shoe, surface, carrying condition and time. 相似文献
15.
Miniaturized Flexible Electronic Systems with Wireless Power and Near‐Field Communication Capabilities 下载免费PDF全文
Jeonghyun Kim Anthony Banks Zhaoqian Xie Seung Yun Heo Philipp Gutruf Jung Woo Lee Sheng Xu Kyung‐In Jang Fei Liu Gregory Brown Junghyun Choi Joo Hyun Kim Xue Feng Yonggang Huang Ungyu Paik John A. Rogers 《Advanced functional materials》2015,25(30):4761-4767
A class of thin, lightweight, flexible, near‐field communication (NFC) devices with ultraminiaturized format is introduced, and systematic investigations of the mechanics, radio frequency characteristics, and materials aspects associated with their optimized construction are presented. These systems allow advantages in mechanical strength, placement versatility, and minimized interfacial stresses compared to other NFC technologies and wearable electronics. Detailed experimental studies and theoretical modeling of the mechanical and electromagnetic properties of these systems establish understanding of the key design considerations. These concepts can apply to many other types of wireless communication systems including biosensors and electronic implants. 相似文献
16.
Dongsoo?KimEmail author Seunghyun?Lim Gunhee?Han 《Analog Integrated Circuits and Signal Processing》2005,45(2):131-141
The eye tracker is a system that detects the point where the user gazes on. The conventional eye tracker using a Charge-Coupled
Device (CCD) camera needs many peripherals and software computation causing high cost, computation time and power consumption.
This paper proposes a single-chip eye tracker using smart CMOS Image Sensor (CIS) pixels. The proposed eye tracker does not
require additional peripherals and operates at higher speed than the conventional approach. The prototype chip was designed
and fabricated for a 32 × 32 smart CIS pixels array with a 0.35-μ m CMOS process. The test results show ± 1 pixel error at
the rate of 125 frame-per-second. The power consumption is 260 mW with 3.3 V supply voltage and the silicon area is 3.8 mm2 相似文献
17.
Materials and Wireless Microfluidic Systems for Electronics Capable of Chemical Dissolution on Demand 下载免费PDF全文
Chi Hwan Lee Jae‐Woong Jeong Yuhao Liu Yihui Zhang Yan Shi Seung‐Kyun Kang Jeonghyun Kim Jae Soon Kim Na Yeon Lee Bong Hoon Kim Kyung‐In Jang Lan Yin Min Ku Kim Anthony Banks Ungyu Paik Yonggang Huang John A. Rogers 《Advanced functional materials》2015,25(9):1338-1343
Electronics that are capable of destroying themselves, on demand and in a harmless way, might provide the ultimate form of data security. This paper presents materials and device architectures for triggered destruction of conventional microelectronic systems by means of microfluidic chemical etching of the constituent materials, including silicon, silicon dioxide, and metals (e.g., aluminum). Demonstrations in an array of home‐built metal‐oxide‐semiconductor field‐effect transistors that exploit ultrathin sheets of monocrystalline silicon and in radio‐frequency identification devices illustrate the utility of the approaches. 相似文献
18.
19.
N.-K. Lee J.-H. Lee S.-M. Lim K.A. Lee Y.B. Kim P.-S. Chang H.-D. Paik 《Journal of dairy science》2014
Subcritical water extract (SWE) of Brassica juncea was studied for antiviral effects against influenza virus A/H1N1 and for the possibility of application as a nonfat milk supplement for use as an “antiviral food.” At maximum nontoxic concentrations, SWE had higher antiviral activity against influenza virus A/H1N1 than n-hexane, ethanol, or hot water (80°C) extracts. Addition of 0.5 mg/mL of B. juncea SWE to culture medium led to 50.35% cell viability (% antiviral activity) for Madin-Darby canine kidney cells infected with influenza virus A/H1N1. Nonfat milk supplemented with 0.28 mg/mL of B. juncea SWE showed 39.62% antiviral activity against influenza virus A/H1N1. Thus, the use of B. juncea SWE as a food supplement might aid in protection from influenza viral infection. 相似文献
20.
Eun-Hee Kim Je-Hyun Lee Yeon-Gil Jung Jung-Chel Jang Ungyu Paik 《Ceramics International》2013,39(4):3993-3998
An additive reagent was introduced into a water glass binder system for enhancing the mechanical properties and dimension stability of a casting mold, and for improving the surface quality of a cast product. Two different processes with three different additive reagents were employed to investigate the relation between fracture strength of the mold and water (H2O) existed in the mold. In processes I and II, the mold samples were coated with a water glass binder, and then dipped into different solutions with additive reagent after and before carbon dioxide (CO2) hardening, respectively. The fracture strength of the mold was enhanced by reducing H2O content in the mold, achieved by a hydrolysis reaction of additive reagents. In process I, the H2O movement was restricted in the mold by the solid phase, converted from the water glass during CO2 hardening. When employing process II, especially in the TEOS used as additive reagent, the fracture strength was significantly increased due to the effective reduction of H2O content in the mold and the homogeneous generation of glass phase by a sol–gel reaction of the additives. 相似文献