• 대한화장품학회지
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• 제42권3호
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• pp.303-309
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• 2016

연령이 증가함에 따라 피부 내부에서는 콜라겐의 합성 능력이 떨어지고 탄력섬유의 손상 및 matrix metalloproteinase (MMPs) 발현이 증가한다. 본 연구의 목적은 눈가에 주름이 형성되기 전에 연령이 증가할수록 피부 내부에서 피부 노화의 징후가 관찰된다는 것을 확인하고, 피부 내부에서 먼저 발생하는 노화의 징후가 칠엽담 지페노사이드 분획물 함유 크림(칠엽담 지페노사이드 크림)의 효능으로 인해 개선되는 것을 확인하는데 있다. 이에 본 연구에서는 육안으로 눈가에 주름이 관찰되지 않는 21 ~ 34세의 한국 여성 52명을 대상으로 임상 시험을 수행하였다. 이들에게서 연령이 증가함에 따라 피부 외부의 노화 징후가 관찰되지는 않지만 피부 내부에서 노화의 징후가 시작되는 시점을 진피치밀도 측정을 통해 확인하였다. 그리고 육안으로 주름이 관찰되지는 않았지만, 진피치밀도가 감소하는 연령대에서 칠엽담 지페노사이드 크림을 4주 및 8주 사용한 후에 진피치밀도 값이 유의하게 증가함을 확인하였다. 따라서 칠엽담 지페노사이드 크림이 피부 내부에서 먼저 진행되는 노화를 효과적으로 개선하는데 도움을 주며, 이 결과를 토대로 칠엽담 지페노사이드 분획물이 향후 주름 개선기능성 화장품 개발에 활용하기 적합하다고 판단된다.

• Corrosion Science and Technology
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• 제22권5호
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• pp.330-340
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• 2023

The objective of this study was to analyze effects of aging time on property degradation of super austenitic stainless steel of PRE 52.8 and super duplex stainless steel of PRE 48.7. To analyze corrosion properties based on aging time, a critical pitting temperature test was performed in a solution of 6% FeCl₃ + 1% HCl and an anodic polarization test was performed in deaerated 0.5N HCl + 1N NaCl solution at a temperature of 50 ℃. Surface hardness was measured to analyze mechanical properties. It was found that corrosion properties and mechanical properties deteriorated rapidly as aging time increased. Critical pitting temperature had the most effect on critical aging time at which property changes occurred rapidly, followed by pitting potential and hardness. This trend was found to be closely related to the fraction of sigma phase. Rate of sigma phase formation was found to be significantly faster in duplex stainless steel than in austenitic stainless steel.

• Elastomers and Composites
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• 제53권2호
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• pp.67-74
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• 2018

Magneto-rheological elastomers (MREs) are smart materials in which the inherent stiffness and damping properties can be changed by the influence of an external magnetic field. The magneto-rheological (MR) effect depends on the orientation characteristics of the dispersed magneto-responsible particles (MRPs) in the matrix. In this study, natural rubber (NR) and ethylene propylene diene rubber (EPDM) were blended and used as a matrix of an MRE. EPDM was pre-cured before blending with NR. The Mooney viscosity, curing characteristics, and mechanical properties were analyzed with various pre-curing conditions of EPDM and the NR/EPDM blend. The results show that excellent mechanical properties of the NR/EPDM blend-based MRE were obtained when the pre-curing time of EPDM was 60 min. The aging property of the NR-based MRE was improved by the introduction of pre-cured EPDM. Also, the anisotropic MRE showed a higher MR effect than that of the isotropic MRE.

• 한국추진공학회지
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• 제20권4호
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• pp.34-39
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• 2016

열분석기인 시차 주사 열량계를 이용하여 $BKNO_3$ 화약의 아레니우스(Arrhenius) 동역학 상수인 활성화 에너지와 Pre-Exponential Factor를 구하였다. 기존의 방법과 달리 고온 가속 노화와 DSC를 병행하여 보다 정밀한 활성화 에너지를 구하였고 열 유속의 적분값을 비교하여 저장 온도에 따른 분율을 구하였다. 이를 통하여 수명 예측을 위한 $BKNO_3$ 화약의 가속노화 시험 조건을 제시하고 열 가속노화에 관한 의미를 재고하였다.

• Metals and materials international
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• 제24권6호
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• pp.1221-1231
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• 2018

The effect of strain aging on tensile behavior and properties of API X60, X70, and X80 pipeline steels was investigated in this study. The API X60, X70, and X80 pipeline steels were fabricated by varying alloying elements and thermomechanical processing conditions. Although all the steels exhibited complex microstructure consisting of polygonal ferrite (PF), acicular ferrite, granular bainite (GB), bainitic ferrite (BF), and secondary phases, they had different fractions of microstructures depending on the alloying elements and thermomechanical processing conditions. The tensile test results revealed that yielding behavior steadily changed from continuous-type to discontinuous-type as aging temperature increases after 1% pre-strain. After pre-strain and thermal aging treatment in all the steels, the yield and tensile strengths, and yield ratio were increased, while the uniform elongation and work hardening exponent were decreased. In the case of the X80 steel, particularly, the decrease in uniform elongation was relatively small due to many mobile dislocations in PF, and the increase in yield ratio was the lowest because a large amount of harder microstructures such as GB, BF, and coarse secondary phases effectively enhanced work hardening.

• 디지털융복합연구
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• 제17권7호
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• pp.157-165
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• 2019

"Aging in place" 실현을 조력하는 제론테크놀로지는 노인의 삶의 질을 높이고 사회적 돌봄 비용을 감소시킬 수 있다. 본 연구는 지역사회 노인의 제론테크놀로지의 사용 전 수용성 및 장애요인을 파악하고 사용 전 수용성의 영향요인을 탐색하는 조사연구로 2019년 3월 16일부터 23일까지 노인복지관을 이용하는 남녀 노인 129명을 대상으로 설문 조사했다. 다중회귀분석을 한 결과 28%의 설명력으로 농촌지역의 대상자와 신체적인 기능이 높을수록, 고비용이나 기술사용에 대한 가족의 지원 부족과 같은 장애요인이 낮을수록 제론테크놀로지의 사용 전 수용성이 높은 것으로 나타났다. 따라서 노인에 대한 보건복지 전략을 개발 할 때 이러한 요인에 대한 고려는 많은 수의 노인이 제론테크놀로지 사용을 촉진하여 향후 노인의 aging in place를 가능하게 할 것이다.

• 한국실내디자인학회논문집
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• 제21권1호
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• pp.248-257
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• 2012

The demand of elderly care facilities due to aging population has been increased and the trend of developed countries implies the necessity of innovate approach for elderly care in Korea. The purpose of this research is to evaluate the flexible elderly housing alternative which has been introduced showing adaptability and small scale. This elderly housing alternative was designed to fulfill the condition of residential facilities for various aging phases from the independent elderly to dependent elderly. The workshop method was used for pre-evaluation of the flexible elderly housing alternative from the viewpoint of administrators, care givers and the elderly. The pre-evaluation is to estimate the facility before finalizing the design so that it facilitates more effective and suitable plan by reducing the trial and error beforehand, unlike the post-evaluation. Major responses of plans were positive and the needs for improvement about some concerns were revealed. Thus, relevant aspects of architectural drawings were amended according to workshop participants' needs and features that require to be reflected during further planning procedures were also improved. The result of this research will develop the flexible elderly housing alternative and contribute to foster environment for the elderly as well.

• 한국보건간호학회지
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• 제21권2호
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• pp.182-192
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• 2007

Purpose: The objectives of this study were to define basic data for developing silver services related to goods, medical care, finance, leisure and residence. Method: In this cross-sectional study, the subjects were 792 pre-elderly and 382 elderly. The data were collected 2005 by using a structured questionnaire from Aug. 19 to Sep. 5. Data were analyzed using descriptive statistics on the SPSS version 12.0 for windows. Result: The pre-elderly had the intention to use massage chair(36.6%), homecare service(29.8%), national pension(35.9%), sports(48.5%) and personal house(59.5%) in the ares of silver goods, medical care, finance, leisure and residence, respectively. The elderly wanted sphygmomanometer(38.7%), homecare service(27.7%), pocket money from their offspring (40.5%), sports(33.5%), and personal house(74.8%). They wanted manpower in the area of reforming of living place, leisure time and education, counseling of silver goods, and management of finance. Conclusion: Based on this study findings, the pre-elderly are thoroughly established for their future than the elderly. It is important to upgrade the silver services and to prepare the manpower for the pre-elderly and the elderly in the future of the aging society.

• 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.

• 한국정밀공학회지
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• 제29권11호
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• pp.1178-1182
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• 2012

The organic linings at flue gas desulfurization systems (FGD system) in power plant have the excellent chemical properties but, lose the anticorrosive properties according to the aging with environment conditions. The properties of the organic linings depend on the manufacturing company. Therefore, the basic properties of organic linings for the preestimate of life time should be examined by conducting the aging and the bond strength test according to temperature. The pre-aging samples were compared with the post-aging samples. The temperature conditions of the aging process were 70, 150 and $200^{\circ}C$. The bond strength was calculated and the cross sections of fracture surface were examined by optical microscope and SEM. The $T_g$ was examined by DSC, DTA and TGA.