• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.645-649
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• 2009

Liquid desiccant cooling technology can supply cooling by using waste heat and solar heat which are hard to use effectively. For compact and efficient design of a dehumidifier, it is important to sustain sufficient heat and mass transfer surface area for water vapor diffusion from air to liquid desiccant on heat exchanger. In this study, the plate type heat exchanger is adopted which has extended surface, and hydrophilic coating and porous layer coating are adopted to enhance surface wettedness. PP(polypropylene) plate is coated by porous layer and PET(polyethylene terephthalate) non-woven fabric is coated by hydrophilic polymer. These coated surfaces have porous structure, so that falling liquid film spreads widely on the coated surface foaming thin liquid film by capillary force. The temperature of liquid desiccant increases during dehumidification process by latent heat absorption, which leads to loss of dehumidification capacity. Liquid desiccant is cooled by cooling water flowing in plate heat exchanger. On the plate side, the liquid desiccant can be cooled by internal cooling. However the liquid desiccant on extended surface should be moved and cooled at heat exchanger surface. Optimal mixing and distribution of liquid desiccant between extended surface and plate heat exchanger surface is essential design parameter. The experiment has been conducted to verify effective surface treatment and distribution characteristics by measuring wall side flow rate and visualization test. It is observed that hydrophilic and porous layer coating have excellent wettedness, and the distribution can be regulated by adopting holes on extended surface.

• 한국의류학회지
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• 제38권3호
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• pp.372-385
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• 2014

Lignin is an abundant natural polymer in the biosphere and second only to cellulose; however, it is under-utilized and considered a waste. In this study, lignin was fabricated into nanofibers via electrospinning. The critical parameters that affected the electrospinnability and morphology of the resulting fibers were examined with the aim to utilize lignin as a resource for a new textile material. Poly(vinyl alcohol) (PVA) was added as a carrier polymer to facilitate the fiber formation of lignin, and the electrospun fibers were deposited on polyester (PET) nonwoven substrate. Eleven lignin/PVA hybrid solutions with a different lignin to PVA mass ratio were prepared and then electrospun to find an optimum concentration. Lignin nano-fibers were electrospun under a variety of conditions such as various feed rates, needle gauges, electric voltage, and tip-to-collector distances in order to find an optimum spinning condition. We found that the optimum concentration for electrospinning was a 5wt% PVA precursor solution upon the addition of lignin with the mass ratio of PVA:lignin=1:5.6. The viscosity of the lignin/PVA hybrid solution was determined as an important parameter that affected the electrospinning process; in addition, the interrelation between the viscosity of hybrid solution and the electrospinnability was examined. The solution viscosity increased with lignin loading, but exhibited a shear thinning behavior beyond a certain concentration that resulted in needle clogging. A steep increase in viscosity was also noted when the electrospun system started to form fibers. Consequently, the viscosity range to produce bead-free lignin nanofibers was revealed. The energy dispersive X-ray analysis confirmed that lignin remained after being transformed into nanofibers. The results indicate the possibility of developing a new fiber material that utilizes biomass with resulting fibers that can be applied to various applications such as filtration to wound dressing.

• 문화기술의 융합
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• 제10권1호
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• pp.325-335
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• 2024

본 연구에서는 패션디자인학과에서 다양한 디자인 전공 학생들의 융합 교육에 따른 SDGs 지속가능한 디자인 교과목 운영 사례를 연구하였다. 문헌 연구를 통해 교과목 운영의 필요성을 살펴보고, 수업설계, 실행, 운영 결과로 교과목을 분석하였다. 지속가능한 디자인 교과목은 2~4학년 학생의 통합 구성으로 패션디자인 및 다양한 디자인 전공 학생이 수강하여 SDGs 과제에 따른 전공 심화와 주제 중심 통합교육에 따른 융합 역량을 강화하였다. 수업에서의 교육내용은 문제 발견과 해결을 통한 디자이너의 지속가능한 가치 추구를 위해 지역업체에서 개발된 폐페트병 섬유의 업싸이클 디자인을 통한 지속가능 발전 목표를 실현하고 다양한 업싸이클 상품 디자인을 개발하고 평가 지표 및 만족도를 평가하였다. 이를 통해 SDGs의 실현 가치를 이해하고 지역문제 해결을 위한 디자인적 접근을 통한 지속가능한 발전 기여와 다양한 디자인 전공과의 융합교육의 중요성을 인식하였다.