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

• 한국의류학회지
• /
• 제24권5호
• /
• pp.696-701
• /
• 2000

Stockings are considered to be excellent in retention of heat in cool weather. This study was to investigate the physiological effects of wearing support panty stocking when exposed to the cool environment from mild environment. Five healthy female college students wearing(ST) or not wearing(NST) support panty stocking, rested at 25$\pm$1$^{\circ}C$, 50$\pm$5% R.H. and were exposed to 18$\pm$1$^{\circ}C$, 50$\pm$5% R.H. for 90 minutes. The results obtained were as follows: Rectal Temperatures were lower in ST than in NST at both environments. Skin temperatures in ST were revealed higher at $25^{\circ}C$, but lower at 18$^{\circ}C$ than in NST. Heat production and total weight loss didn't show significant difference between ST and NST. Total thermal conductance from the body to the environment was higher in ST than in NST at 18$^{\circ}C$. It was suggested that wearing support panty stocking would keep the body warm in mild environment, but facilitate heat loss from the body in cool environment.

• 한국환경과학회지
• /
• 제19권1호
• /
• pp.81-87
• /
• 2010

Cool island intensity urban green space was investigated based in Dalsung Park, that is one of the largest parks in Daegu. Cool island intensity(CII), which is defined as the temperature difference between the green space and its surrounding built-up areas, shows time variations. A through-year measurement(2008-2009) of ground level air temperature revealed seasonal variation and relationship to the atmospheric condition of CII. The temperature variation in the park and the reference downtown Daegu was as same order as CII. The noontime CII is larger in summer than that in winter due to the leaf fall of the park trees. On the other hand, seasonal variation of nighttime CII is not so clear. The nighttime CII was larger under the stable atmosphere.

• KIEAE Journal
• /
• 제16권6호
• /
• pp.95-101
• /
• 2016

Purpose: This study aims to identify the effect of temperature reduction by the application of cool roof coatings to Changwon City Hall in South Gyeongsang Province. The indoor and outdoor temperatures of the cool roofing building were analyzed and compared to that of an existing building with green-colored roof coated with waterproof polyurethane. Method: The surface temperatures and reflectivity of rooftops, surface temperatures of ceilings and the interior, and outdoor temperature and humidity of the two aforementioned buildings were measured from June to September in 2014. The measurements were taken every 10 min. Result: The surface temperature of the building with the cool roof was lower by a maximum of $9^{\circ}C$ with the reflectivity of the rooftop at an average of 0.55, which is higher than that of the building with green polyurethane by approximately 0.3. The temperature of the ceiling inside the building with the cool roof was about $1{\sim}2^{\circ}C$ lower than that of the ordinary building. Also, the indoor temperature of the office with cool roof coatings was about $0.5{\sim}1.0^{\circ}C$ lower than that of the office with green-colored roofing building. The results show that cool roof coatings can lower the temperature of buildings. In the next research, the reduction in consumption of energy for air conditioning will be investigated by utilizing building energy simulation tools.

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

• 한국컴퓨터정보학회논문지
• /
• 제11권5호
• /
• pp.223-230
• /
• 2006

차세대 웹은 표현 중심의 웹을 데이터 중심의 웹으로 이끌 것으로 예측되며, Web 2.0과 시맨틱 웹의 기술적 결합이 될 것이다. 차세대 웹은 시맨틱 처리, 웹 플랫폼과 데이터 결합이 매우 중요한 기술적 요소이다. 이 중에서 데이터 결합에 사용되는 Cool URI는 영속적이고 사용자 친화적인 URI를 제공하는 기술이며, 이미 블로그 등에서 매우 중요하게 사용되고 있다. 그러나 Cool URI는 한글과 같은 다국어 환경에 적합하도록 구성되어 있지 않으며 여러 인코딩이 혼재된 국내 웹 환경에서는 쉽게 사용하기 어려운 상황이다. 본 논문에서는 이러한 Cool URI를 다국어 식별자와 같이 사용하기 위한 기술적인 고려 사항 및 Cool URI 웹 컴포넌트에 관하여 논한다. 제시한 방식은 인코딩의 종류에 상관없이 동일한 기능을 제공하며, 다른 애플리케이션에서 쉽게 사용 가능하도록 파일 시스템 기반과 CGI 기반 방식을 모두 지원한다. 여러 환경에서 실험한 결과는 구현된 웹 컴포넌트가 설계 목표를 만족함을 보여주었다.

• 한국의류학회지
• /
• 제21권4호
• /
• pp.669-676
• /
• 1997

The purpose of this study is to examine the effect of the improved cold tolerance resulting from cool clothing in winter on heat tolerance in summer. Ten healthy women were divided into two groups, cold group(C group) (n=5) and warm group(W group) (n=5) . In the previous study, C group was proved that their cold acclimatization was achieved through wearing cool clothing from September to February of the following year, while Wgroup was not proved because of wearing warm clothing during same period. After February, no more clothing training was continued in two groups. To determine the heat tolerance, both groups were exposed from a thermoneutral environment(25$\pm$1$^{\circ}C$, 50$\pm$5% R.H.) to a hot environment (35$\pm$1$^{\circ}C$, 50$\pm$5% R.H.) before and after clothing training, respectively September in 1994 and truly in 1995. Rectal temperature, skin temperatures, thermal sensation and comfort were measured every 10 min., and Os uptake was measured at 10, 45, 85 min. after entering the chamber for 5 min. Body weight was measured before and after the experiment and amount of local sweat was measured during the 90 min long experiment. The results are as follows: Rectal temperatures in 35'c environment of C group were increased after training when compared with before clothing, while those of W group were not changed. But the changes of rectal temperature and heat production during 90 min in hot environment were almost the same in two groups after training. And mean skin temperatures, the changes of mean skin temperatures during 90 min in hot environment, total sweat amount and local sweat amount after training were also the same in two groups. From these results, it might be supposed that the heat loss of two groups were the same but the heat production, especially heat production during rest in C group was higher than in Wgroup. This fact suggests that the increase of rest heat production from cold acclimatization in winter is maintained to summer of the following year. And mild cold acclimatization coming from westing cool clothing does not have a negative effect on heat tolerance.

• 천문학회보
• /
• 제41권1호
• /
• pp.68.4-69
• /
• 2016

We report preliminary results of KaVA observations of central galaxies in cool-core and non cool-core clusters. The main goal is to study how cooling environments of galaxy clusters affect the central AGN activities especially at its innermost region. For KaVA observations, 7 radio bright AGNs have been selected from the extended Highest Flux Galaxy Cluster Sample (eHIFLUGCS; the X-ray flux limited & all sky galaxy cluster catalog) with various cooling timescales. In our previous KVN study, we have found that most AGNs in the cool-core clusters show the hint of pc-scale jet-like features while the ones in the non cool-core clusters do not. Using the KaVA 22/43 GHz data of a much higher resolution than the KVN resolution, we have investigated detailed pc-scale jet properties such as physical size, morphology, and radiative age. Based on the KaVA data, we discuss the effect of cluster cooling environment on the evolution of AGNs in the cluster center.

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

• 한국의류학회지
• /
• 제14권2호
• /
• pp.152-163
• /
• 1990

The purpose of this study is to experimentally analyze the relationship between structural characteristics of cotton fabrics and their cool-and-warm felling in order to develop more comfortable fabrics. Comfort in textile products has been emphasized as consumers preferred performance to fashion of clothing. Thermal comfort of clothing is a basic parameter of the comfort sensation which is usually represented by the cool-and-warm feeling felt by human skin. Cloo-and-warm feeling is perceived by the heat flux which transfers heat energy stored in an object to skin. We feel warm (cool) if the temperature of nerve extremity in skin ascends (descends). As cool-and-warm feeling determines the comfort sensation of clothing, it is important to develop new comfort fabrics. Although considerable works have been made on the body, clothing, and environment, there has been no research study on the structural characteristics of fabrics and their cool and warm feeling. Cool-and-warm feeling is closely related to the transient heat transfer property. This research study used the cotton fabrics manufactured in Korea as sample and measured $q_{max}$ value with thermal property measuring instrument (Thermo-Labo II type). $q_{max}$ values estimated by polynomial regression equation were compared with those observed in this study. This study also identified the structural parameters of cotton fabrics for a specific range of $q_{max}$ values. The findings of this study can be summarized as follows: 1) As the thickness, porosity and air permeability of cotton fabrics increase, $q_{max}$ value decreases. 2) As the fabric count and over factor of cotton fabrics increase, $q_{max}$ value also increases. 3) $q_{max}$ values have been estimated by simple and polynomial regression equations developed in this study. Regression curves which have been plotted by polynomial regression equations also provided with the range of structural parameters for a specific range of $q_{max}$ values of cotton fabrics. This study would be significant in that it has identified the structural Parameters for the cool-and-warm feeling of cotton fabric at $65\%$ relative humidity.