• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 춘계학술발표회논문집(2)
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• pp.635-640
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• 1995

Two techniques for the verification of the phase separation in ferrite phase of primary pressure bounary component materials, the primary cause of thermal aging embrittlement, are presented. Data base of room-temperature Charpy V-notch impact energy during reactor service was estimated as a measure of the degree of embrittlement. The serviceable period of CF-3 and CF-8 alloys as the primary pressure boundary components may be acceptably extended for 60 years of lifetime. However, the integrity of CF-8M alloys can be degraded seriously after several years of service in the nuclear reactor.

• Archives of Plastic Surgery
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• 제33권4호
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• pp.525-529
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• 2006

Purpose: Facial nerve injury is a rare but feared complication of face lift. Uncertainty as to the depth and vulnerability of the facial nerve in face lift dissection causes some surgeon, particularly novices, to dissect slowly. Excessively thin flaps can be made because of fear of nerve injury, contributing to skin slough. Methods: From September 1998 to February 2003, the authors operated on 34 aging face patients using classical face-lift. We had analysed about quantity of skin removal and degree of elevated flap. The authors have found quantity of skin removal was 1.5-2.0 cm, degree of elevated flap was 40-45 degree on average. Results: The authors performed preauricular pre-excision face-lift technique on 12 aging face patients from July 2003 to Feburary 2005 based on experienced surgery. This technique reduced fear of dissecting skin flap necrosis and facial nerve injury because of firmly attached pre-auricular skin removed in advance. Conclusions: We easily dissected SMAS without visual field disturbance, nerve damage and reduced operation time and bleeding loss compared to classical face-lift.

• 한국식품저장유통학회지
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• 제12권6호
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• pp.613-616
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• 2005

배추김치의 발효숙성을 $4^{\circ}C$에서 29일간 실시하면서 pH 및 적정산도 측정과 전자코를 활용한 향기성분 패턴 분석을 실행하였다. $4^{\circ}C$에서 숙성한 배추김치의 pH는 저장 초기에는 큰 변화를 보이지 않다가 숙성 후 14일째부터 낮아졌고, 적정산도는 초기 $0.26\%$에서 16일째에 $0.43\%$까지 일정하다가 이후부터 급증하여 29일에는 $1.15\%$에 도달하였다. 전자코 분석 결과, 배추김치의 향기성분 패턴은 숙성기간이 늘어나면서 제1주성분 값이 negative에서 Positive로 이동하는 경향을 보였다. 29일간숙성 중의 모든 배추김치 향은 전자코의 제1주성분과 제2주성분 값으로 나타낸 그림 상에 크게 5 그룹으로 나타낼 수 있었다. 즉, 4일, 6-14일, 16일, 21-25일과 29일로 구분할 수 있고, 이를 pH와 적정산도의 결과와 함께 고려하여,4일, 6-14일(이상 산도에 따라 구분한 1기), 16일(산도에 따라 구분한 2기), 21-25일과 29일(이상 산도에 따라 구분한 3기)로 구분할 수 있었다. 따라서 배추김치의 이화학적 성질분석과 향기성분 패턴 분석을 위한 전자코 실험결과 숙성온도와 숙성기간에 따른 배추김치의 숙성도를 예측할 수 있었다.

• 대한토목학회논문집
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• 제39권4호
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• pp.523-530
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• 2019

포트홀 발생 및 관련 교통사고 건수는 매년 꾸준히 증가하는 추세이며 이에 따른 인명피해, 차량파손에 따른 비용손실 등 도로 이용자의 직 간접적인 피해를 증가시키고 있다. 일반적으로 아스팔트 혼합물은 생산과정부터 시공 후 공용에 따라 지속적으로 노화가 진행된다. 포장 노화는 균열과 수분침투로 박리를 야기하고 반복적인 윤하중에 의해 포장구조를 약화시켜 포트홀을 유발하게 된다. 본 연구에서는 노화가 아스팔트 콘크리트 포장에 미치는 영향을 검토하기 위해 노화정도에 따른 부착성능 평가와 수분민감성 평가를 수행하였다. 연구결과 노화에 따라 아스팔트 바인더의 점성이 증가해 부착강도가 2~3배 이상 증가하였다. 또한 가속 노화시킨 아스팔트 혼합물의 경우 간접인장강도의 증가뿐만 아니라 TSR 값도 4.2~8.9 % 증가하는 것으로 나타났다. 이에 따라 골재에 아스팔트 바인더가 피복된 상태에서 노화가 진행될 경우 아스팔트 바인더와 골재의 부착력이 증가하여 박리 저항성이 향상되는 것으로 분석되었다.

• Computers and Concrete
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• 제19권5호
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• pp.527-535
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• 2017

In this study, an aging deformation statistical model for a unique high and steep rock slope was proposed, and the aging characteristic of the slope deformation was better reflected. The slope displacement was affected by multiple-environmental factors in multiple scales and displayed the same tendency with a rising water level. The statistical model of the high and steep rock including non-aging factors was set up based on previous analyses and the study of the deformation and residual tendency. The rule and importance of the water level factor as a non-aging unit was analyzed. A partitioned statistical model and mutation model were established for the comprehensive cumulative displacement velocity with the monitoring study under multiple factors and multiple parameters. A spatial model was also developed to reflect and predict the whole and sectional deformation character by combining aging, deformation and space coordinates. A neural network model was built to fit and predict the deformation with a high degree of precision by mastering its feature of complexity and randomness. A three-dimensional finite element model of the slope was applied to approach the structure character using numerical simulations. Further, a three-dimensional finite element model of the slope and dam was developed, and the whole deformation state was analyzed. This study is expected to provide a powerful and systematic method to analyze very high, important and dangerous slopes.

• Archives of Plastic Surgery
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• 제44권1호
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• pp.65-71
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• 2017

Background This study evaluated dynamic changes in eyebrow position related to aging. Methods Female participants were recruited and separated into two groups aged 20-30 years (the younger group, n=20; mean age, 24.8 years) and 50-70 years (the older group, n=20; mean age, 55.8 years). Photogrammetry was used to determine the eyebrow position at the medial canthus (MC), lateral limbus, lateral canthus, and lateral end point (EP) for 6 actions: smooth opening (the reference action) and closing of the eye, forward gaze, maximum opening and closing of the eye, and maximum frown. Videos were also recorded. Results No differences in eyebrow position were detected at the MC when opening or closing the eyes smoothly, gazing straight ahead, or closing the eyes maximally. For all 6 actions, the position of the lateral EP in the older group was significantly lower than in the younger group (P=0.003), and the smallest degree of vertical movement at this point was found in both age groups (P<0.001). Vertical movement at the 4 landmarks of the eyebrows decreased with aging. Conclusions Eyebrow position was unchanged at the MC with aging, except at maximal eye opening and maximal frown. No differences in eyebrow position were observed between the younger and older groups when eyes were maximally closed, except at the EP. It is important to focus on correction of the lateral EP for periorbital rejuvenation.

• 통합자연과학논문집
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• 제16권3호
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• pp.75-80
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• 2023

Bipolar disorder is a mental illness characterized by extreme mood and behavioral swings, such as highs of euphoria and lows of depression. It is a socially significant disorder in which people with the disorder experience intense mood swings and, for those with severe bipolar disorder, it is even difficult leading a normal life. High stress levels in people with mental illness can lead to neuroendocrine disruption, and it is strongly linked to aging. When the neuroendocrine system becomes vulnerable to these mental illnesses and stress, it is likely to accelerate aging. And it's the epigenetic clock that can measure the extent of this accelerated aging. The Epi clock, a pan tissue clock, measures aging through DNA methylation, and the degree of methylation is modified and changed by environmental conditions in the body. Therefore we wanted to check the changes in the epigenetic age of the patients with bipolar disorder. While we found no significant differences in epigenetic age, we did confirm the possibility that people with bipolar disorder have different methylation than normal people. We also found that the EPIC array data fit better on the Epi clock than on the Horvath clock with age-accelerated data from normal people.

• 조명전기설비학회논문지
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• 제13권3호
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• pp.56-63
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• 1999

전력계통의 변전소 설비들은 계통의 확장에 따라 점점 복잡하고 거대해지고 있다. 또한, 몇몇 장비들은 점점 노후되고, 종종 예상치 않은 고장을 일으킨다. 변전소 설비들 중 변압기의 신뢰도를 증가시키기 위해서, 변압기의 진단기법 개발이 매우 필요하다. 본 연구에서는, 전력용 변압기의 용해 가스들을 근거로 KSOM(Kohonen Self Organizing Map)에 의한 열화정도와 원인의 분석기법을 개발하였다. KOSM은 용해가스에 의해 구성된 다차원 패텅을 이차원 평면에 지형학적 맵핑이 가능하다. 그리고 정장변압기에 대한 열화의 정도와 잠재적인 열화의 가능성을 제안된 정량적 지표에 의해 제시하였다. 아울러, 변압기의 열화과정을 제안된 지표를 근거로 특정한 변압기에 대해 분석하였다. 제안된 방법의 타당성을 입증하기 위해서 사례연구가 수행되고, 그 결과를 제시하였다.

• 대한기계학회논문집A
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• 제23권11호
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• pp.2014-2021
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• 1999

The present investigation is concerned with the degradation characteristics of cast stainless steel(CF8M), exposed to the $\sigma$-phase degradation at $700^{\circ}C$. In the present paper, the degradation of CF8 M at $700^{\circ}C$ is evaluated by a non-destructive test, DL-EPR(double loop electrochemical potentiokinetic reactivation). The surface of specimens is observed by using scanning electron microscopy after DL-EPR test. Also. chromium contents of matrix, grain boundary and ferrite phase are analyzed by electron probe X-ray micro analyzer. Through the experiments, the following results are obtained 1) The degree of sensitization(DOS) of CF8M aged up to 15hr at $700^{\circ}C$ is increased with acing time while that is decreased with aging time from 15hr to 150hr. 2) The impact energy decreases with increase of $\sigma$-phase while DOS increases with $\sigma$-phase until aging time reaches to 15hr. After the aging time. 15hr, the $\sigma$-phase and the rate of impact energy with respect to aging time decreases. Therefore the degradation behavior of the CF8M can be evaluated by comparing SEM micrographs and the value of DOS.

• 한국콘텐츠학회논문지
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• 제19권1호
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• pp.329-338
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• 2019

본 연구는 정신질환자의 노화불안과 주관적 안녕감 정도를 확인하고 노화불안이 주관적 안녕감에 미치는 영향을 파악하기 위해 서술적 조사연구 방법으로 수행되었다. D와 C 지역에 거주하는 정신질환자 107명(조현병=48명, 기분장애=59명)이 연구에 참여하였다. 수집된 자료는 SPSS 23.0 program을 이용해 기술 통계, t-test, one-way ANOVA, Pearson correlation, Multiple regression을 이용하여 분석하였다. 연구결과, 대상자의 노화불안은 7점 만점에 $3.95{\pm}0.80$이었고, 주관적 안녕감은 6점 만점에 $3.53{\pm}0.73$이었으며, 노화불안과 주관적 안녕감은 통계적으로 유의한 부적상관관계(r= -.48, p <.001)가 있었다. 회귀분석 결과 노화불안, 주관적 건강상태, 직업상태는 주관적 안녕감에 영향을 미치는 유의한 변수로 확인되었으며, 이들 변수의 총 설명력은 31.1%이었다. 따라서 정신질환자의 주관적 안녕감을 향상시키기 위해 노화불안을 관리할 수 있는 체계적이고 통합적인 중재가 필요하다.