• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
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• pp.396-399
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• 2003

4H-SiC un diodes with field limiting rings(FLRs) were fabricated and characterized. The dependences of reverse breakdown voltage on the number of FLRs, the distance between p-base main junction and first FLR, and activation temperatures, were investigated. Al and B ions were implanted and activated at high temperature to form p-base region and p+ region in the n-epilayer. We have obtained up to 1782V of reverse breakdown voltage in the un diode with two FLRs on loom thick epilayer. The differential on-resistances of the fabricated diode are $5.3m{\Omega}cm^2$ at $100A/cm^2$ and $2.7m{\Omega}cm^2$ at $1kA/cm^2$, respectively. All pn diodes with FLRs have higher avalanche breakdown voltages than that of diode without an FLR. Regardless of the activation temperature, the un diode with a FLR located 5um apart from main junction has the highest mean breakdown voltage around 1600V among the diodes with one ring. On the other hand, the pn diode with two rings showed different behavior with activation temperature. It reveals that high voltage SiC pn diodes with low on-resistance can be fabricated by using the FLR edge termination.

• 한국세라믹학회지
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• 제46권2호
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• pp.175-180
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• 2009

Multilayer ceramic capacitors (MLCCs) have continually been made smaller in size and larger in capacity in resent years. However, the end termination electrode is still thick in many MLCCs. In this study, we used small grain glass frit to embody thin film and highly densification in the end termination by improve sintering driving force with well-dispersion and rising surface energy. Pastes were fabricated using size changed glass frit, such as 0.1 ${\mu}m$, 0.5 ${\mu}m$, 1.0 ${\mu}m$, 4.0 ${\mu}m$. Fabricated pastes were applied 05A475KQ5 chip and fired various sintering temperatures to analyze sintering behavior of pastes. Consequently, small glass frit used pastes have many merits than larger, such as well-dispersion, improve cornercoverage and surface roughness, possibility of low temperature sintering. However, we confirmed that small glass frit used pastes have narrow sintering window by rapid completion of sintering densification.

• 자연과학논문집
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• 제14권1호
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• pp.51-61
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• 2004

박테리오 파아지 T7 RNA 중합효소는 어떤 전사인자도 관여하지 않는 간단한 시스템으로 파아지 RNA 중합효소와 전사촉진제만의 단백질-DNA 상호작용에 의해 전사가 진행된다. T7 파아지의 숙주 세포의 파괴에 관여하는 T7 파아지 lysozyme은 전사를 억제하고, 전사종결에 영향을 미친다. 따라서 T7 파아지 lysozyme 유전자를 대장균 발현 벡터에 삽입하여 pT7lys를 얻었고, 발현시켜 Ni-NTA column chromatography로 순수 분리하였다. T7 파아지 lysozyme은 SDS-gel에서 단일 밴드로 확인하였으며, amidase 활성 역시 확인하였다. 염기서열 특이적 전사 종결에 미치는 T7 파아지 lysozyme의 역할을 알아보기 위하여, rrnB T1 전사종결 인자 부근에서의 전사연장 복합체 제조에 미치는 T7 파아지 lysozyme의 영향력을 조사하였다. 이 결과 T7 파아지 lysozyme 존재 하에 형성되는 전사연장 복합체는 불안정함을 알 수 있었다.

• 한국통신학회논문지
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• 제22권8호
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• pp.1803-1813
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• 1997

영상 복원의 목적은 훼손 요인을 제거하여 원 영상에 가장 근접하게 만드는 것이다. 이는 정칙화 반복 복원 방법을 통해 이루어 질 수 있다. 영상 복원 방법에서 좋은 종료 규칙은 보다 우수한 화질의 복원 영상과 보다 적은 계산량이라는 두가지 목적을 모두 만족시킬 수 있어야 한다. 이에 본 논문에서는 반복 복원 방법의 다항식적인 표현을 이용한 종료 규칙을 제안한다. 이 규칙에서는 각 반복 복원 단계에서의 복원 영상과 원 영상의 추정 오차를 구해낸 뒤, 이를 선호에 의한 오차와 잡음에 의한 오차로 구분하여, 이 들간의 비율을 달리 작용한다. 이로써 보다 우수한 복원 영상을 보다 적은 계산량에 의해 얻을 수 있다. 이를 위해 잡음 억제 변수(Noise Suppression Parameter)라는 새로운 변수를 정의 하며, 또한 임의의 잡음 정도에 대하여 적정 지점에서 반복을 중지시킬 수 있도록 하는 잡음 억제 변수의 추정식을 제안한다. 제안한 종료 규칙으로 실험한 결과 잡음이 상대적으로 많은 경우에는 최소의 mse를 갖는 지점에서, 잡음이 상대적으로 적은 경우에는 적당히 제한된 반복 횟수를 갖는 지점에서 반복을 멈추었으며 기존의 종료 규칙에 비하여 뛰어난 성능을 나타내었다.

• Restorative Dentistry and Endodontics
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• 제19권1호
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• pp.114-123
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• 1994

The purpose of this study was to examine the shear bond strength of resin-enamel bond formed at specific time intervals after the termination ov vital bleaching. A total of 72 human extracted maxillary premolars were divided into nine groups : untreated control (group 1) ; enamel treated with 35% hydrogen peroxide(group 2, 3, 4, 5) ; and enamel reated with 15% carbamide peroxide gel (group 6, 7, 8, 9). After the treatment with 35% hydrogen peroxide for 2 hours and 15% carbamide peroxide for 24 hours, adhesion of a resin to bleached enamel was formed at 1 hour (group 2, 6) and 24 hours(group 3, 7) ; 3days(group 4, 8) and 7 days(group 5, 9) post-termination of bleaching treatment. A $3{\times}3mm$ mold was filled with Scotchbond Multi-Purpose and Z100. After 24 hours later, the specimens were shear-tested at crosshead speed 1mm/min and analyzed statistically. Fractured specimens from group 1,2, 6 were gold-coated with Eiko ion coater and observed under Scanning electron microscope at 25KV. The following results results were obtained : 1. Bonds formed at 1 hour post-termination of 35 % hydrogen peroxide(P<0.01) and 15 % carbamide peroxide bleaching treatment groups(P<0.05) showed significantly lower shear bond strength than untreated group. 2. Bonds formed at 24 hours, 3 days and 7 days post-termination of 35% hydrogen peroxide and 15 % carbamide peroxide bleaching treatment groups showed no significant differences in shear bond strength with untreated group(p>0.05). 3. SEM examinations of the untreated fracture specimen indicated cohesive fracture within enamel and exposed enamel prisms, but the bleached fracture specimens indicated adhesive fracture.

• 약학회지
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• 제42권1호
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• pp.101-107
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• 1998

The antiparkinsonian agent l-deprenyl, a selective monoamine oxidase (MAO)-B inhibitor, is metabolized in part to l-methamphetamine and l-amphetamine. l< /I>-Deprenyl was evaluated for amphetamine and methamphetamine-like discriminative stimulus effects in rats and its mechanism of action was investigated. Rats were trained under a 5-response, fixed ratio schedule of stimulus-shock termination or a 10-response. Fixed-ratio schedule of food-presentation which discriminate between d-amphetamine (1mg/kg, i.p.) and saline or d-methamphetamine (1mg/kg, i.p.) and saline in a two-lever, operant conditioning procedure. Full generalization was obtained to d-amphetamine (1~3mg/kg). d-methamphetamine (1~3mg/kg) and l-deprenyl (17~30mg/kg) under both the food presentation and stimulus shock termination schedule. l-Deprenyl has dose-dependent amphetamine-and methamphetamine-like discriminative stimulus properties in rats only at doses of 17 and 30mg/kg. Reversible MAO-B inhibitor, RO 16-6491 didn`t show any amphetamine-like discriminative properties. Aromatic amino acid decarboxylase inhibitor, NSD 1015 decreased % responding of l-deprenyl in the methamphetamine-trained rats under the stimulus-shock termination schedule. SKF-525A produced partial inhibition of methamphetamine-like discriminative effects of l-deprenyl under the food presentation schedule. These results suggest that l-deprenyl has no abuse liability at the therapeutic range but there needs some caution at high doses and furthermore, drug discrimination studies under the food presentation and shock termination schedule are useful for the assessment of abuse liability of psychostimulants.

• 한국항행학회논문지
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• 제26권1호
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• pp.15-21
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• 2022

본 논문은 부하에 서로 다른 복소 임피던스로 종단되면서 출력 분배 비율이 다른 비대칭 전력 분배기를 구현하는 방법을 제안하였다. 제안된 방법은 출력의 종단된 복소 임피던스를 전송선로만을 이용하여 특정 임피던스 또는 특정 복소임피던스 값으로 정합하는 방법을 사용하여 설계하였으며, 또한 종단 복소 임피던스 포트 사이의 고립도를 만족하기 위한 고립회로를 설정하는 방법을 제시하였다. 이러한 방법의 타당성을 증명하기 위해서, 입력포트는 50 Ω이고 서로 다른 출력 복소 임피던스를 갖으면서 분배 비율이 k² = 3 dB 와 1.7 dB 인 경우와 모든 포트가 서로 다른 복소 임피던스로 종단되어 있으면서 분배 비율이 k² = 3 dB를 갖는 비대칭 전력분배기를 중심주파수 2 GHz에서 설계하였으며, 전기적 특성의 실험 결과는 시뮬레이션과 잘 일치함을 확인하였다.

• 대한두개안면성형외과학회지
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• 제25권2호
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• pp.77-84
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• 2024

Background: The facial artery is an important blood vessel responsible for supplying the anterior face. Understanding the branching patterns of the facial artery plays a crucial role in various medical specialties such as plastic surgery, dermatology, and oncology. This knowledge contributes to improving the success rate of facial reconstruction and aesthetic procedures. However, debate continues regarding the classification of facial artery branching patterns in the existing literature. Methods: We conducted a comprehensive anatomical study, in which we dissected 102 facial arteries from 52 embalmed and formaldehyde-fixed Vietnamese cadavers at the Anatomy Department, University of Medicine and Pharmacy, Ho Chi Minh City, Vietnam. Results: Our investigation revealed eight distinct termination points and identified 35 combinations of branching patterns, including seven arterial branching patterns. These termination points included the inferior labial artery, superior labial artery, inferior alar artery, lateral nasal artery, angular artery typical, angular artery running along the lower border of the orbicularis oculi muscle, forehead branch, duplex, and short course (hypoplastic). Notably, the branching patterns of the facial artery displayed marked asymmetry between the left and right sides within the same cadaver. Conclusion: The considerable variation observed in the branching pattern and termination points of the facial artery makes it challenging to establish a definitive classification system for this vessel. Therefore, it is imperative to develop an anatomical map summarizing the major measurements and geometric features of the facial artery. Surgeons and medical professionals involved in facial surgery and procedures must consider the detailed anatomy and relative positioning of the facial artery to minimize the risk of unexpected complications.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1134-1139
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• 2003

Tracking is a fundamental technique which is able to be applied to gesture recognition, visual surveillance, tangible agent and so forth. Especially, multiple object tracking has been extensively studied in recent years in order to perform many and more complicated tasks. In this paper, we propose a new approach of multiple object tracking which is based on discrete event. We call this system the DEMOT (Discrete Event based Multiple Object Tracking). This approach is based on the fact that a multiple object tracking can have just four situations - initiation, continuation, termination, and overlapping. Here, initiation, continuation, termination, and overlapping constitute a primary event set and this is based on the change of the number of extracted objects between a previous frame and a current frame. This system reduces computational costs and holds down the identity of all targets. We make experiments for this system with respect to the number of targets, each event, and processing period. We describe experimental results that show the successful multiple object tracking by using our approach.

• 대한산업공학회지
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• 제40권6호
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• pp.609-617
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• 2014

Lately there are many approaches for decreasing the retail prices for mobile telecommunication in response to higher demand of the consumer welfare. Related on this perspective, there have been many disputes how the MTR (mobile termination rate)s from the whole market has influences on the consumer prices at the retail market. Therefore, we need a timely review about the possibility of the reduction of retail prices with MTR policies. The purpose of this paper is to study the relationship between MTR and retail prices. For this purpose, we can identify three kinds of arguments by reviewing the previous literatures. We empirically analyze the relationship with latest European data and Korean annual data. Furthermore, we also examine whether the relationship would depend on the competition structure. The results imply that decreasing MTR would result in reduction of the retail prices but the effect would be enhanced by improvement of market concentration.