• Proceedings of the KAIS Fall Conference
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• 2009.05a
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• pp.109-113
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• 2009

이 연구는 교정치료중인 환자의 구강건강영향지수(OHIP)와 자아존중감에 영향을 미치는 요인을 파악하기 위해 대구시내에 소재한 교정 전문치과 4곳에서 교정치료를 받고있는 환자 200명을 대상으로 설문지 조사방법을 이용하여 대상자의 일반적 특성 및 교정치료 특성, 구강건강영향지수, 자아존중감을 조사 분석하여 교정치료환자의 구강건강영향지수 및 자아존중감에 영향을 미치는 요인을 분석하였다. 그 결과, OHIP에 영향을 미치는 요인으로는 연령이 낮을수록(P<0.01), 구강건강상태가 좋을수록(P<0.001), 가족의 권유로 교정치료 받는사람이(P<0.05), OHIP에 영향을 주는 요인으로 분석되었으며, 자아존중감에 영향을 미치는 요인으로는 남자가(P<0.05), 미혼이(P<0.01), 수입이 많을수록(P<0.05), 자아존중감에 영향을 주는 요인으로 나타났다.

• Journal of Environmental Health Sciences
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• v.26 no.2
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• pp.49-58
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• 2000

The present study was performed to investigate photodegradation rate constants and degradation products of phosphamidon and profenofos by the USEPA method. The two pesticides were very stable in 16 days exposure of sunlight from September 3 to 22, 1999 and humic acid had no sensitizing effect on the photolysis of each pesticide in sunlight. In the UV irradiation test, phosphamidon was rapidly degraded as increasing UV intensity. In case of UV irradiation with TiO2 and with TiO2 powder amount, degradation of profenofos showed no significant difference with UV irradiation. Photodegradation rate of profenofos was slower than that of phosphamidon. In order to identify photolysis products, the extracts of degradation products were analyzed by GC/MS. The mass spectra of photolysis products of phosphamidon were at m/z 153 and 149, those of the profenofos were at m/z 208 and 240, respectively. It was suggested that the photolysis products of phosphamidon were 0, 0-dimethyl phosphate(DMP) and N, N-diethylchloroacetamide, those of profenofos were 4-bromo-2-chlorophenol and 0-ethyl-S-propyl phosphate.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.4
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• pp.517-525
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• 1996

A Simple AC complex circuit analysis for LCL type series resonant converter with phase shift control is proposed. Based on these analyses, a set of characteristic curves which allows a optimal design procedure for this converter is shown, without increasing the volt-ampere rating of tank circuit Especially, inverter output peak current can be minimized in both full load and partial load conditions. The presented design considerations can make the load range wide from full loads to light loads achieving turn-on with zero voltage switching (ZVS) operation. The detailed analysis and experimental results show the effectiveness of the proposed design algorithms. (author). refs., figs., tab.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.11c
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• pp.1763-1766
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• 2003

본 논문에서는 다양한 응용 분야에 이용되는 스마트 카드의 효율성과 보안성을 높이기 위하여 스마트 카드와 단말기간의 인증을 설계하였다. 기존의 스마트 카드와 단말기의 PIN 인증을 이용하지 않고, 스마트 카드가 단말기간에는 지문 인증을 수행하도록 하여 보안성을 높였고, 스마트 카드내에 저장된 지문의 정보를 효율적으로 최소화하여 저장함으로서 스마트 카드의 저장공간을 최소화시키는 동시에 단말기 상에서 입력된 지문과 스마트 카드 내에 지문이 매칭될 때 발생하는 계산 부하도 줄일 수 있다. 제안된 인증시스템은 무선 단말기와 같은 장비를 인증하기에 적당하다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04a
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• pp.500-502
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• 2003

본 논문에서는 다양한 응용 분야에 이용되는 스마트 카드의 보안성을 높이기 위하여 스마트 카드와 무선 단말기, 무선 단말기와 사용자간의 인증을 구분하여 설계하였다. 기존의 스마트 카드와 지문을 이용한 인증 시스템은 스마트 카드내의 지운 정보의 유출이나 스마트 카드 상에서 지문 매칭시 현실적인 문제뿐 안 아니라 카드와 단말기 양측을 모두 인증하는데 어려움이 있었다. 그래서 본 논문은 기존의 스마트 카드와 단말기의 양방향 인증 등을 이용하지 않고, 스마트 카드가 무선 단말기를 인증한 다음. 우선 단말기에 부착된 지문 센서를 이용해 입력된 사용자의 지문 정보로 단말기가 사용자 인증을 하도록 하였다. 제안된 인증 시스템은 스마트 카드 및 지문을 이용하여 사용자측(스마트 카드와 카드 소유자)과 단말기간의 상호인증을 제공한다. 이러한 이중 인증 메카니즘을 무선 인터넷 환경에서 보다 안전한 인증 시스템을 제공할 수 있을 것이다.

• Proceedings of the KIPE Conference
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• 2010.11a
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• pp.252-253
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• 2010

본 논문에서는 Molten Carbonate Fuel Cell (MCFC)의 느린 동특성을 Load Leveler와 2차 전지로 구성된 back-up 시스템으로 보완하여 독립운전을 가능하게 한 대용량 연료전지 발전시스템을 제안한다. 제안한 독립운전 시스템의 발전 용량 및 battery 용량은 실제 전력사용 통계자료를 근거로 최적으로 산정되며, 컴퓨터 시뮬레이션을 통하여 타당성을 검증한다.

• Journal of the Semiconductor & Display Technology
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• v.22 no.4
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• pp.166-171
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• 2023

This paper presents the synaptic characteristics of IGZO memristors in neuromorphic computing, using MATLAB/Simulink and NeuroSim. In order to investigate the variations in the conductivity of IGZO memristor and the corresponding changes in the hidden layer, simulations are conducted by using the MNIST dataset. It was observed from simulation results that the recognition accuracy could be dependent on various parameters of IGZO memristor, along with the experimental exploration. Moreover, we identified optimal parameters to achieve high accuracy, showing an outstanding accuracy of 96.83% in image classification.

• Physical Therapy Korea
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• v.15 no.2
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• pp.38-43
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• 2008

To reduce winging scapula, various exercise protocols have been widely used by clinicians. Selective serratus anterior strengthening, and restoring balanced function, are especially recommended to reduce winging scapula. The purpose of this study was to investigate visual biofeedback using a real time video camera display system for monitoring scapular winging during arm lowering. For this study, 13 males with winging scapular were recruited during arm lowering. Electromyography (EMG) activity was recorded from the serratus anterior (SA) and upper trapezius (UT) of the right side and compared with normal EMG activity using a paired t-test. The study showed, through visual biofeedback, that EMG activity significantly increased in the SA and significantly decreased in the UT (p<.05). These results suggest that visual biofeedback can be recommended as an effective method for scapular eccentric control, to prevent scapular winging during arm lowering.

• Korean Journal of Materials Research
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• v.19 no.11
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• pp.625-630
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• 2009

Embedding of active devices in a printed circuit board has increasingly been adopted as a future electronic technology due to its promotion of high density, high speed and high performance. One responsible technology is to embedded active device into a dielectric substrate with a build-up process, for example a chipin-substrate (CiS) structure. In this study, desmear treatment was performed before Cu metallization on an FR-4 surface in order to improve interfacial adhesion between electroless-plated Cu and FR-4 substrate in Cu via structures in CiS systems. Surface analyses using atomic force microscopy and x-ray photoemission spectroscopy were systematically performed to understand the fundamental adhesion mechanism; results were correlated with peel strength measured by a 90o peel test. Interfacial bonding mechanism between electrolessplated Cu and FR-4 substrate seems to be dominated by a chemical bonding effect resulting from the selective activation of chemical bonding between carbon and oxygen through a rearrangement of C-C bonding rather than from a mechanical interlocking effect. In fact, desmear wet treatment could result in extensive degradation of FR-4 cohesive strength when compared to dry surface-treated Cu/FR-4 structures.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.609-612
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• 1998

Pyroelectric properties of rhombohedral $Pb(ZrxTi_1-x)O_3ceramics$ with various Zr/Ti ratios of 84/16, 87/13, 90/10, and 93/7 are investigated using dynamic method. The response characteristics of PZT samples are examined by considering frequency dispersion. Since the reorientation of the grain does not the influence on the increase of frequency at low frequency (2~200Hz), the maximum pyroelectric response can be obtained with the change of spontaneous polarization. However, the pyroelectric response of PZT samples could be reduced as the spontaneous polarization decreases due to the restrain of the reorientation of the grain with the increasing of requency at high frequency (200~2000Hz). We have obtained the good pyroelectric response in the PZT sample having 84/16 Zr/Ti ratio, then the pyroelectric coefficient (${\gamma}$) and the figure of merit (FV) were $17.3nC/\textrm{cm}^2K$ and 2.28$\times$10-11Ccm/J, respectively. The noise equivalent power (NEP), the detectivity (D*) were 1.21$\times$10-7W/Hz$\frac{1}{2}$ and 8.26$\times$106cmHz$\frac{1}{2}$/W, respectively.