• Elastomers and Composites
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• 제33권3호
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• pp.159-167
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• 1998

고무제품의 노화는 인간의 노화 처럼 오존, 자외선, 산소 등의 작용에 의하여 매우 복잡하게 진행된다. 노화에 대한 이해는 매우 중요하나 너무나 복잡하기 때문에 이에 대한 논문이 매우 드물다. 본문에서는 EPDM과 천연고무의 노화거동을 이해하고자 하였고 가황물과 과산화물 가교물의 노화거동을 서로 비교하여 보았다. 실험결과 파산화물에 의한 가교물이 황에 의한 가교물보다 노화면에서는 좋게 나타났다. 저자는 본 연구가 고기능성 고무 제품을 제조하는데 도움이 되리라 믿는다.

• 한국분말재료학회지
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• 제13권3호
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• pp.172-177
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• 2006

Aging characteristics and mechanical properties of commercial 7xxx series Al composites were investigated from viewpoint of ceramic contents. After sintering process, sintered densities of blended and composite powder were 95 and 97%, respectively. Each part was solution-treated at $475^{\circ}C$ for 60 min and aged $175^{\circ}C$. And two-step aging was also performed form $120^{\circ}C$ to $175^{\circ}C$. The aging behavior of the sintered composite pow-der was different from that of sintered blended powder. The peak aging time of the composite was rapid as well due to strain. Before aging, mechanical properties of sintered composite powder was significantly higher than that of sintered blended powder. These increments of properties were directly affected by ceramic particles. However, after aging, incremental rate of mechanical properties was slowed in the composite.

• 한국안전학회지
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• 제19권4호
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• pp.1-7
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• 2004

This study investigated the effects of aging on the transformation behavior of $Ti-50.1at\%$ Ni alloy by means of differential scanning calorimetry. It was found that aging in the temperature range of $350^{\circ}C\~550^{\circ}C$ induced complex transformation behavior, involving the R-phase and multiple-stage martensitic transformation. Usually aged Ni-rich NiTi alloys undergo martensitic transformation on cooling from high temperatures in two step : B2 to R and then R to Bl9'(normal behavior). But under certain ageing conditions, the transformation can also occur in three or more step(unusual multiple step behavior). In the present study we use differential seaming calorimetry(DSC) for a systematic investigation of the evolution of transformation behavior with ageing temperature and time.

• 한국심리학회지 : 문화 및 사회문제
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• 제22권2호
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• pp.137-163
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• 2016

본 연구의 목적은 계획된 행동 이론(Theory of Planned Behavior; Ajzen, 1991)에 입각하여 중고령 근로자의 활동적 노년과 생산적 노년을 고찰하는 것으로, 노년기 행동에 대한 참여 과정에 대한 동기화 과정을 비교하였다. 이러한 동기화 요소로 활동적 노년과 생산적 노년 각각에 대한 태도, 주관적 규범, 행동 통제감을 연구하였으며, 이 세 요소가 노후준비라는 행동의도에 영향을 주는지 검증하였다. 또한, 노후준비의 세부요소가 활동적 노년과 생산적 노년 각각에 미치는 영향이 어떻게 다른지를 함께 검증하였다. 50~69세의 중고령 근로자 192명에게 설문조사를 통해 자료를 수집하였다. 분석 결과, 활동적 노년에 대해서는 주로 태도와 행동 통제감이 노후준비를 통해서 활동적 노년에 영향을 미치는 것으로 나타났다. 반면 생산적 노년에 대해서는 규범과 행동 통제감이 노후준비를 매개로 생산적 노년에 영향을 미치는 것으로 나타났다. 세부적인 분석 결과, 활동적 노년에 대해서는 사회적 노후준비를 매개 변인으로 했을 때 간접효과가 유의미했으며, 생산적 노년에 대해서는 정서적 및 사회적 노후준비를 매개변인으로 했을 때 간접효과가 유의미한 것으로 나타났다. 연구 결과를 바탕으로 중고령 근로자의 활동적 노년과 생산적 노년에 대한 시사점을 제시하였다.

• 한국세라믹학회지
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• 제24권5호
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• pp.477-483
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• 1987

Cr2O3 doped Pb(Zr0.525 Ti0.475)O3 piezoelectric ceramics were prepared from reagent grade oxide mixture, PbO, ZrO2, TiO2 and Cr2O3. Piezoelectric and aging properties of specimens were measured for various additions of Cr2O3. Generally, it has been known that aging rate decreased with Cr2O3 addition by stabilizing the domain wall. But hysteresis loops showed that the domain destabilization was occurred at high electric field (larger than 10KV/cm). In smaller additions of Cr2O3 (0-0.2mol%), aging rate increased and microcracks were created with increasing poling filed due to increasing internal stress. In larger additions of Cr2O3(0.4∼0.6mol%), aging rate decreased with increasing poling field.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2007년도 춘계학술대회 논문집
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• pp.105-109
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• 2007

Aging society appears immediate social problem in Korea. Housing for aging is required independent and comfortable housing life to live considering about feature of elderly. It is necessary field to prepare. Aged person who suffers the aging process several stages gets changing weak, so living environment is important aging person aspect of social, psychological and physical point. Finally, aged person living together requires facilities for the naturally communicating and active things. Community of aged person required organization of space for keeping independence and connection with each other. According to space of community, housing for aging should have a different access route. In conclusion, congregate housing of the elderly should be planed organization of space to be solved anxiety and tension and to be aware of joining the community.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1065-1066
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• 2006

The aging behavior of sintered Al composites with various ceramic contents was investigated. 2xxx series blended powder was used as the starting powder. Ceramic contents were 0wt.% and 5wt.%. The blended powders were compacted at 250MPa. The sintering process was performed at $620^{\circ}C$ for 60min in a $N_2$ atmosphere. Each part was solution-treated at $518^{\circ}C$ for 60min and aged at $180^{\circ}C$. The Rockwell hardness at the peak aging time increased with ceramic contents. However, the peak aging time at maximum hardness was reduced with increased ceramic contents.

• 대한금속재료학회지
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• 제47권2호
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• pp.71-78
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• 2009

The precipitation behavior of solute carbon and nitrogen strongly affects the mechanical properties of low-carbon automotive panel. In the present study, the effects of aluminum and solute nitrogen on the bake hardenability and strain aging of extremely low-carbon steel with carbon content below 15 ppm has been investigated. The ferrite grain size and distribution of precipitates were varied with the amount of aluminum content of 0.003 to ~ 0.100 wt% in a constant solute carbon and nitrogen. With increasing the aluminum content, the ferrite grain size is increased and strain aging is delayed. The strain aging is also delayed by increasing the annealing temperature, although the ferrite grain size is not much changed.

• 여성건강간호학회지
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• 제25권4호
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• pp.392-408
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• 2019

Purpose: The purpose of this study was to examine the effects of an aging management program on the resilience and successful aging of middle-aged women. Methods: A quasi-experimental study with a non-equivalent control and pre-post test design was used. The participants were 39 middle-aged women living in urban areas in Korea. The experimental group (n=22) received the aging management program for a total of 10 weeks, 90 minutes to 120 minutes per week. The aging management program consisted of strategies to enhance the behavior, promotion conditions, and habits of the program, including various activities for middle-aged women. The data were analyzed using χ² tests, independent t-tests, and repeated measures analysis of variance with the SPSS/WIN 21.0 program. Results: The resilience score of the experimental group was significantly higher level than the score of the control group in the time-to-group interactions (F=3.70, p=0.029). The successful aging score of the experimental group was significantly higher than the score of the control group in the time-to-group interactions (F=5.86, p=0.004). However, the sub-hypotheses of resilience (self-regulation and interpersonal relationships) and successful aging (physical aging adaptation and psychological age adaptation) were partially accepted. Conclusions: The aging management program for middle-aged women was identified as an effective intervention for promoting resilience and successful aging in middle-aged women. Therefore, this suggests that the aging care program could be a useful intervention program to improve the mental health of middle-aged women living in communities.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2011년도 춘계학술발표회 논문집
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• pp.339-347
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• 2011

This study was carried out in order to manufacture the high quality coated paper. High quality coated paper includes not only present state but also the state of the future. So in this study, acrylic-styrene emulsion which polymerized in laboratory was compared with SB(Styrene-butadiene) latex during thermal aging. The coated paper with three different formulations which controlled the dosage of acrylic-styrene emulsion were prepared. The coated paper were thermally aged at $105^{\circ}C$ for 18days and the optical properties were measured. Brightness, whiteness and CIE L value were higher during thermal aging with increasing amount of acrylic-styrene emulsion. CIE $a^*$ value was higher and CIE $b^*$ value decreased with increasing amount of acrylic-styrene emulsion. These results indicate that high quality coated paper which has anti -thermal aging property can be manufactured with acrylic-styrene emulsion.