• KIEAE Journal
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• 제15권1호
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• pp.117-127
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• 2015

The cool surface ratio could be used as a proxy of the overall thermal environment contributing to heat islands in urban area. This research proposes a comparative evaluation framework in an objective and quantitative way for measuring cool surface ratios. Two university campuses (Kyungpook National University: KNU, South Korea and UC Davis: University of California, Davis, USA) were selected as case study sites in order to monitor cool surface condition. Google Earth combined with digital maps realistically identified the major type of cool surfaces such as cool roofs and water bodies in the study area. Cool surfaces were sparsely identified over the KNU campus while the UC Davis campus was heavily covered by cool surfaces such as cool roofs and water bodies, resulting in almost four times more first-grade cool surfaces, as compared to KNU. It is confirmed that standard remote sensing technology can offer the viable method of measuring and comparing the campus-wide cool surface condition. It is anticipated that this research output could be used as a valuable reference to initiate a nation-wide cool surface strategy since objective evidence has been provided based on area-wide measurement for the cool surface in the two university context.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.860-865
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• 2006

The traditional Korean Ondol System that is a radiant floor heating system was made as warm floor and cool indoor temperature. Nowaday, Ondol is developed as the hydronic floor heating system. But unbalance of floor temperature and indoor temperature is occurred bocause strengthen thermal insulation and airtightness in building changes thermal performance. To solve these problems, we examine actual indoor environment of heating system methods in existing apartments and present the new method of floor heating system. The existing heating system made definite indoor temperatures but floor temperatures that is $22^{\circ}C-26^{\circ}C$ was maintained. To solve these problems, we adopted the differential heating system which made warm area and cool area. A differential heating system was made different pitches of heating pipe in single zone and ratio of warm area to cool area is 1 to 2. As a result of experiments, warm area temperature is $40.7^{\circ}C$, cool area temperature is $36.1^{\circ}C$. A difference of temperature between both area is 4K. A distribution of indoor vertical temperature is similar to both warm area and cool area.

• 토지주택연구
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• 제11권3호
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• pp.75-82
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• 2020

The urban heat island phenomenon that accelerates global warming has always been controversial when summer heatwaves have occurred since it was first investigated and described by Luke Howard in the 1810s. In Korea, since 2014, government have been interested in Cool Roof and painted white coating on the rooftops of the aging and weak buildings, and the cool roof business has expanded nationwide. However, the roof occupies 20-25% of the entire city surface, much less than 37-45% of the pavement area consisting of roads, parking lots and sidewalks, there is a need to expand the policy of Cool Pavement as a way to reduce the urban heat island phenomenon. Domestic cities are high-rise buildings centered on apartments, and the area occupied by outer walls is larger than that of rooftops compared to foreign low-rise buildings. Therefore, as a way to reduce the urban heat island phenomenon, there is a need for a policy to expand the Cool Roof in buildings and use Cool Wall in parallel. Therefore, this study aims to present the expansion of Cool Wall in buildings and Cool Pavement in urban areas, expanding the installation range of Cool Roof, by comparing and reviewing the thermal characteristics of eco-friendly ceramic coating with excellent thermal proof performance and coatings used for roof waterproofing.

• 한국의류산업학회지
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• 제22권1호
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• pp.66-75
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• 2020

This study helps develop cool-touch functional dance sportswear. We suggest a draft design for dance sportswear that chooses appropriate cool-touch functional materials based on an investigation of the changes of body surface temperature before and after exercise, the physical properties of cool-touch materials on the market, and the preference for cooling tools. The results are as follows. First, cool-touch functional sportswear products on the market utilize materials such as PCM, Delta fabric, high gauge fabric, and ice chips as well as incorporate functions such as UV block and eyelets for enhanced breathability. Polyester and polyurethane fibers are mainly used for cool-touch functional sportswear. Second, the neck area showed the highest surface temperatures (32.7℃ and 32.1℃) before and after exercise. Body surface temperatures measured after exercise were also lower than temperatures measured before exercise when wearing dance sportswear. Third, as for the physical properties of cool-touch materials, material 1 showed amaximum drying speed (130 min), material 3 the best moisture absorption speed (122 × 132 min), and material 4 the best thermal conductivity (0.013 7 w/m·K). Fourth, a draft design for a cool-touch functional dance sportswear was suggested, including a neckband made of removable soft PVC material on the neck area and applying material 4 in F1, B4, S2 and lower arm areas and material 1 in the armpit area. Deodorant tape was also attached to the armpit area for added comfort and antibacterial deodorant effect.

• 대한방사선기술학회지:방사선기술과학
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• 제38권2호
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• pp.155-161
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• 2015

본 연구는 고주파 열치료 시 내부냉각방식 cool-tip의 냉각수 온도에 따른 소작 특성을 확인하기 위하여 소간을 이용하여 냉각수 온도변화에 따른 소간의 소작 특성의 변화를 통해 냉각수 온도변화와 소작 특성의 상관관계를 확인하고자 하였다. 실험에 사용된 소간은 2 cm cool-tip 사용 시 $4{\times}4{\times}4cm^3$, 3 cm인 cool-tip 사용 시에는 $6{\times}6{\times}6cm^3$로 소간을 절제하였으며, 소작된 소간은 MRI를 이용하여 영상검사를 실시하였으며, Freehand 기법으로 소작된 부위의 면적과 둘레를 측정하였다. 2 cm, 3 cm cool-tip을 사용하여 6분, 12분 소작 시 cool-tip 온도가 상승함에 따라 면적과 둘레는 감소함을 나타냈으며, cool-tip 온도와 면적 및 둘레의 상관관계는 통계학적으로 유의한 결과를 나타내었다(p=.000). 소작 범위에 대한 실제 측정과 MRI을 이용한 측정을 비교한 결과 MRI를 이용한 면적과 둘레 측정이 더 정확한 것을 확인하였으며, 대응표본 T-검정을 이용한 통계적 결과 또한 유의하였다(p=.038). 고주파 열치료 장비의 cool-tip 냉각수 온도가 증가함에 따라 소간의 소작 범위가 감소한 원인은 고주파 열치료 장비의 에너지가 정확히 전달되지 못하고 탄화가 발생하기 때문이다. 따라서 고주파 열치료에서 탄화의 발생을 줄이고, 고주파 에너지가 정확히 전달되어 치료 효과를 높이기 위해서는 냉각수의 온도를 낮은 온도로 일정하게 유지하여 사용하여야 고주파 열치료의 효과가 증대될 것이라 사료된다.

• KIEAE Journal
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• 제13권6호
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• pp.83-91
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• 2013

Cool roofs are currently being emerged as one of important mechanism to save energy in relation to the building. It is specifically proposed that the changing trends of rooftop surface temperature in the flat roof building model could be used effectively as an indicator to reduced cooling load reduced by cool roof since it can present stable temperature record, that is not influenced according to the nearby physical as well as human variables. The temperature of cool roof in summer was lower around $20^{\circ}C$, compared to the general roofs. Such a seasonal or daily comparative study for rooftop temperature in the building model will highlight that the cool roof efficiency could be calculated in much area-wide context according to rooftop color distribution in urban residential area. It is anticipated that this research output could be used as a valuable reference in identifying energy saving by cool roof since an objective monitoring has been proposed based on the rooftop temperature in the building model, fully quantitative performance of thermal infrared image.

• 한국의류학회지
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• 제42권5호
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• pp.799-808
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• 2018

This study develops triacetate-containing functional fabrics with a cool-touch and cool-absorbent. For this purpose we used composite yarns made using triacetate filament and PET High absorbance quick dry filament as well as the composite fabric woven. The fineness of the yarn and structure of fabric varied the cover factor varied. The blend ratio of triacetate was differently set. When the triacetate content was the same, the cool touch of the fabric having a large cover factor and small SMD increased. The surface became smooth and the contact area became large; in addition, both the Qmax value and the cool-touch became large. In the case of similar density, the cool-touch of the fabric having a large content of triacetate increased. The cool-absorbent of the fabric containing triacetate showed a similar level of the PET High absorbance quick dry filament fabric treated with and endothermic cooling agent. It was possible to develop a functional coolness fabric with a cool-touch and a cool-absorbent when the content of triacetate and cover factor were well combined.

• 감성과학
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• 제5권3호
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• pp.53-59
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• 2002

The surface fibers on the fabric is one of decisive factors which affects human sensory evaluation as well as heat and moisture transfer characteristics. In this study the length and distribution of surface fibers that are extruded from the fabric surface of the wool/wool blend fabrics (14 wool fabrics and 10 wool blend fabrics) and its contribution to subjective sensory evaluation were investigated. In order to quantify the length and distribution of surface fibers, image analysis and wavelet transform technique were introduced. Instant warm-cool feeling of touch, Q$\_$max/, and contact area were also measured and related to the quantified surface fibers. To figure out the effect of surface characteristics on sensory evaluation, human sensory responses to three adjectives which represent surface characteristics and warm-cool feeling of touch were obtained and analyzed. The relationship between the quantified surface fibers assessed by wavelet energy and both warm-cool reeling of touch, Qmax, and human sensory response were discussed.

• 한국조경학회지
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• 제29권2호
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• pp.77-84
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• 2001

This study was carried out to investigate the utilizing of cool-season turfgrass in areas, excluding greens, of Korean golf courses. Data collected from 120 golf courses were subjected to frequency and T-test analysis using SPSSWIN. The results obtained were as follows: 1) seventy eight golf curses were utilizing cool-season turfgrass in areas except of the greens. At thirty five golf courses (46.0%) of them, the area utilized appeared tee, green collar, green approach etc. (tee>green collar>green approach). At 37 golf courses(48.7%), a mix of Kentucky Bluegrass and Perennial Ryegrass was utilized and the ratio of the mix was 70:30(v/v). At 57 golf courses(76.0%), seed sowing was utilized. 2) In Korean golf courses, the cognition of utilizing cool-season turfgrass depended on the existence of the practice. The cognition of the experienced was more´ affirmative´ than that of the inexperienced. 3) In the experienced, the preference was determined by turfgrass quality and good appearance and recuperative rate of cool-season turfgrass. In the inexperienced, the preference was determined by turfgrass quality god appearance. 4) The experienced recommended the mix of Kentucky bluegrass and Perennial Ryegrass. 5) It seems that the golf courses having used cool-season turfgrass have difficulties in the maintenance in summer while the golf courses without using cool-season turfgrass have difficulties in the maintenance in summer and the selection of turfgrass variety.

• 한국초지조사료학회지
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• 제41권3호
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• pp.189-197
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• 2021

Climate change effects are particularly apparent in many cool-season grasslands in South Korea. Moreover, the probability of climate extremes has intensified and is expected to increase further. In this study, we performed climate change vulnerability assessments in cool-season grasslands based on the analytic hierarchy process method to contribute toward effective decision-making to help reduce grassland damage caused by climate change and extreme weather conditions. In the analytic hierarchy process analysis, vulnerability was found to be influenced in the order of climate exposure (0.575), adaptive capacity (0.283), and sensitivity (0.141). The climate exposure rating value was low in Jeju-do Province and high in Daegu (0.36-0.39) and Incheon (0.33-0.5). The adaptive capacity index showed that grassland compatibility (0.616) is more important than other indicators. The adaptation index of Jeollanam-do Province was higher than that of other regions and relatively low in Gangwon-do Province. In terms of sensitivity, grassland area and unused grassland area were found to affect sensitivity the most with index values of 0.487 and 0.513, respectively. The grassland area rating value was low in Jeju-do and Gangwon-do Province, which had large grassland areas. In terms of vulnerability, that of Jeju-do Province was lower and of Gyeongsangbuk-do Province higher than of other regions. These results suggest that integrating the three aspects of vulnerability (climate exposure, sensitivity, and adaptive capacity) may offer comprehensive and spatially explicit adaptation plans to reduce the impacts of climate change on the cool-season grasslands of South Korea.