• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.118-120
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• 1996

We've been reported recently that increase of installing big power converting equipment which makes harmonics result in damage on transformer for incoming and load. Specially, harmonics that cause overheat and aging is severer in cast-resin transformer a kind of dr type than in oil one. The goal of this paper is to prove the process for aging of transformer that result from harmonics in according to both of theory and actual measurement on site. And we introduce diagnostic methods to estimate aging condition of cast-resin transformer in accordance with simulation.

• 대한기계학회논문집A
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• 제32권5호
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• pp.444-450
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• 2008

The conventional studies of the aging effect on cardio-vascular system are mostly obtained from human experiences and can only provide local information. In this study, the effect of fatigue fracture of arterial wall on the blood pressure was investigated by hemodynamic analysis. The aging process was simulated with three stages. The pulse wave velocity increased with age. The systolic blood pressure increases consistently but diastolic blood pressure decreases with age. The simulated results show in good accordance with the clinical ones.

• 한국전기전자재료학회논문지
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• 제20권2호
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• pp.183-187
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• 2007

Fractal mathematics is being highlighted as a research method for classification of image. But the application of Fractal dimension(FD) has been requited the complicated calculation method because of its complex repetition progressing. In this paper, it has been developed the new approach method to express the Fractal Dimension(FD) for aging level calculation and estimation system of outside insulator using special image processing algorithm. As a result after FD testing, the recognized aging estimation of FD has a very characteristics compared to the conventional visual inspection.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.1275-1277
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• 2004

In this paper, we propose a new diagnosis method of DC/DC converter aging. The method is based on the variations of parasitic resistor for the aging process. We apply an on-line diagnosis of DC/DC converter because the observation is not a device, but a system. This study proposes a method of DC/DC converter diagnosis by analyzing the variations of model on the variations of parasitic resistor.

• 한국산학기술학회논문지
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• 제6권4호
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• pp.285-290
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• 2005

고무제품의 기계적 특성은 혼합물 성분, 경화 상태 공정 및 충진제 같은 많은 요소에 기인된다. 우리 연구의 목적은 N-isopropyl-N'-chloro-P-phenylene diamine, 항산화제의 영향을 열적 상태에서 노화 및 오존 균열에 관해 조사하였다. 이 연구에서 항미생물 고무매트의 퇴화가 연구되었는데, 항산화제 함유 및 항산화제가 함유되지 않은 항균매트에 관한 열적 상태의 노화 및 오존 균열을 조사하였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.275-276
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• 2023

In order to prevent disaster risks caused by building aging in advance, the prevailing opinion is that it is urgent to actively improve systems such as mandatory safety inspections, and to calculate risks and develop safety management systems due to building aging. The need for systematic risk management continues to be emphasized in the process of safety inspection and repair of old buildings, but the risk management and safety management techniques of each construction entity have not been established in practice. Accordingly, this study aims to analyze the vulnerability factors of aging buildings and provide basic data on the development of a risk rating calculation model for old buildings and the efficiency of safety management systems in the future.

• 대한치과의사협회지
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• 제21권12호통권175호
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• pp.1005-1010
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• 1983

To study the eruption process of the permanent tooth, esp., 1st molar, the author took 303 cases of oblique cephalogram (Male. 162 cases, Female: 141 cases) from age 3 to 8 yea old children, and observed the vertical change and axial change. The result were as follow: 1. The mesial end of upper 1st molar was closer to the occlusal plane than the distal, and they were erupting toward the occlusal plane by aging. In the case of lower 1st molar, the distal end was closer to the occlusal plane than the mesial and the occlusion showed the tendency to accord with the plane to be settled by aging. 2. Eruption rate of the upper and lower 1st permanent molar increased rapidly at 5 or 6 years of age. 3. Axial inclination of lower 1st permanent molar to the mandibular plane decreased gradually from 3 years of age, except for 6 years of age. There was some increase at 5 or 6 years of age.

• 가정과삶의질연구
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• 제21권1호
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• pp.25-36
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• 2003

This study was conducted to reconstitute a family life education program for caregivers and to analyze the system of implementation. Based largely on a pre-existing program for caregiving families, I developed a new educational program. Personal time management and personal needs management were added in the content of the program order to help enhance self-esteem and internal control. The reconstituted educational program, which consists of 6 sessions, was implemented on a small group of caregivers in Jeollabukdo Province who support their elderly parents. The effectiveness of the program was evaluated by a pre-test, a post-test, a follow-up test and open-questionnaire reports. The results from the post-test suggest that the program has been effective in improving the knowledge on aging process, internal control and self-esteem. But the follow-up test results show the program has been effective only in improving the knowledge on aging process. According to the open-questionnaire reports, the program seems to have been effective in improving interpersonal relationships and changing attitudes toward their elderly parents.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.573-575
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• 2005

In the steel industry, a steel melting electric arc furnace is used to produce both carbon and alloy steels. Steel scrap which is charged into the furnace is heated by means of electric arc between graphite electrodes and the scrap. In this melting process, current is supplied to the furnace through HCC(high current cable) which connect the furnace and transformer. Four HCCs are assigned to each phase in our system to divide the current. Since a sudden cable breaking result in the shutdown of melting process, an aging detection of HCC is very important for both an improvement of productivity and cost reduction. In this paper, the aging of the HCC is estimated by using the current ratio between four HCCs.

• 한국응용과학기술학회지
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• 제20권4호
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• pp.346-352
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• 2003

BaTiO$_3$, powders were prepared by sol-gel process from different aging time and reaction temperature. Particle shape, size and crystal structure of prepared $BaTiO_3$ powders were analyzed by SEM, XRD and FT-IR. Effect of aging time alternation didn't particularly show up. Spherical nano-sized $BaTiO_3$ powders were obtained from condition more than reaction temperature $55^{\circ}C$, and obtained sintered $BaTiO_3$ powders of tetragonal phase from heat-treatment at $1,100^{\circ}C$.