• 대한가정학회지
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• 제42권10호
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• pp.91-104
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• 2004

The purpose of this study was to examine the differences of clothing microclimates and the subjective sensations according to age, gender and clothing weight for $19^{\circ}C$ air temperature. This study was done to gain fundamental data related to saving heating energy and to improve health through wearing underwear (long johns) in lower indoor temperatures. The subjects were divided into four groups (6 young males, 5 young females, 6 old males, 6 old females), and our experiment consisted of three conditions; the first condition was wearing long underwear in $19^{\circ}C$ air (19CUW condition); the second condition was without wearing long underwear in $19^{\circ}C$ air (19C condition); and the third condition was without wearing underwear in $24^{\circ}C$ air (24C condition). The experiment showed that the clothing microclimate temperature and humidity was the lowest in the 19C condition and the highest in the 24C condition irrespective of age and gender. The clothing microclimate in the 19CUW condition was not significantly distinguishable from the other conditions. Clothing microclimate temperature and humidity when the subjects responded thermal comfort was $28\~34^{\circ}C$ and $15\~40\%$RH without any significant difference according to age and gender. For the thermal sensation, the 24C condition was regarded as the warmest environment by the four groups, and the next preference was the 19CUW condition (p<0.001). Young females and old males showed a tendency to feel colder than young males and old females. For the thermal sensation of hands and feet, the young groups felt the warmest in the 24C condition and the coolest in the 19 C condition (p<0.001). However, old males felt neutral for the foot thermal sensation without any significant difference between the three conditions. Old females felt neutral for both the hands and feet thermal sensations without any significant difference between the three conditions. Thermal preference was the highest in the 24C condition for the 4 groups. In the 19CUW condition, for the thermal preference, most young males and females responded 'No change'; on the other hand, mea of the old responded 'Warmer'(p<0.001). It was the 24C condition that the 4 subject groups felt the most thermally comfortable. In the 19CUW condition, over $80\%$ of responses of each group expressed satisfaction and in the 19C condition, over $80\%$ of responses of each group, except young females, expressed satisfaction. In conclusion, in view of the clothing microclimate and subjective sensations, the 24C condition was the condition that gave subjects the least cold stress and the best subjective preference. However, the 19C condition and the 19CUW condition was not such a cold stress as to give healthy subjects a thermal burden.

• 한국전기전자재료학회논문지
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• 제17권5호
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• pp.526-529
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• 2004

The nematic liquid crysta](NLC) aligning capabilities using a-C:H thin film deposited at the three kinds of rf bias condition were investigated. A high pretilt angle of NLC on low substrate rf bias applied a-C:H thin films was observed and the low pretilt angle of the NLC on high substrate rf bias applied a-C:H thin films was observed. Consequently, the high NLC pretilt angle and the good aligning capabilities of LC alignment by the IB alignment method on the a-C:H thin film deposited at 1 W rf bias condition can be achieved. It is considered that pretilt angle of the NLC may be attributed to substrate rf bias condition and IB energy time. Therefore, LC alignment is affected by topographical structure forming strong IB energy.

• 한국초지조사료학회지
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• 제15권3호
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• pp.157-163
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• 1995

The objective of this study is to obtain the basic data for investigating the effects of organic reserves on winter survial or regrowth yield. Dry matter, nitrogen and non-structural carbohydrate content of plants grown under $5^{\circ}C$ or $20^{\circ}C$ of culture temperature during 25 days were investigated. The dry matter content of leaves and roots were significantly reduced under $5^{\circ}C$ compared with $20^{\circ}C$culture condition. Comparing with the dry matter per plant under $20^{\circ}C$, those in leaves and roots under $5^{\circ}C$ decreased to 25% and 10%, respectively, after 25 days of temperature treatment. Total nitrogen content in leaves under $20^{\circ}C$ and $5^{\circ}C$ increased to 68% and 39% compared to the initial lenel(day O), respectively, during 25 days after temperature treatment, Nitrogen content in roots highly increased under 5 C while there was a little change under $20^{\circ}C$ condition. The nitrogen contents in roots under $5^{\circ}C$ and $20^{\circ}C$ were 39.0 and 30.8mgJg DM, respectively, after 25 days of temperature treatment. Total contents of soluble carbohydrate in both leaves and roots under $5^{\circ}C$ were higher than those under $20^{\circ}C$ condition. After 25 days of temperature treatment under$5^{\circ}C$ , their contents in leaves and roots were 1.4 and 2.0 times higher than those of under $20^{\circ}C$ condition. Stach atent in roots under $20^{\circ}C$ was less changed, while thatof under $5^{\circ}C$ greatly increased from 64.8 to 178.7mglg DM duling 25 days. 'Ihese results clearly showed that an accumulation of both nitrogen and non-structural carbohydrate in the plants occured under low temperature condition.e condition.

• 농업생명과학연구
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• 제43권3호
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• pp.27-34
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• 2009

녹차 잎 1.5 g에 증류수 100 mL을 가하여 $75^{\circ}C$에서 5분 동안 추출하여 녹차 음료를 제조하였다. 저장 조건을 달리하여 A 녹차 음료 (빛을 인위적으로 차단하지 않음, 자연 상태의 대기 조건, 비타민 C 무첨가), B 녹차 음료 (빛을 알루미늄 호일로 감싸서 차단함, 질소를 불어넣어 자연 대기를 질소로 치환하였음, 비타민 C 30 mg/100 mL 첨가), C 녹차 음료 (빛을 알루미늄 호일로 감싸서 차단함, 질소를 불어넣어 자연 대기를 질소로 치환하였음, 비타민 C 무첨가)로 구분하여 $4^{\circ}C$에서 28일간 저장한 후, 유용 성분을 분석하였다. 총페놀 함량의 경우 저장 초기에 비하여 저장 28일 후 A 녹차 음료는 71.50%, B 녹차 음료는 73.88%, C 녹차 음료는 75.07%로 감소하였다. DPPH 라디컬 소거능은 저장 초기에 비하여 A 녹차 음료는 87.87%, B 녹차 음료는 92.93%, C 녹차 음료는 88.39%이었다. 녹차의 유용 카테킨인 epigallocatechin gallate (EGCG)는 28일간 저장 후에 A 녹차 음료는 130.61%, B 녹차 음료는 136.47%, C 녹차 음료는 4.34%이었다. 이상의 결과는 녹차의 저장 조건이 녹차 음료의 성분에 영향을 미치며, 빛, 질소 치환, 비타민 C가 매우 중요함을 시사하였다.

• 한국지역사회생활과학회지
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• 제25권4호
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• pp.549-556
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• 2014

This study evaluates the thermal insulation and evaporative resistance of a waterproof and breathable garment system and determines the factors influencing its thermal performance. The experimental garments were composed of underwear (shirts with 100% wool and 100% polyester) and outerwear (jackets and pants with a vapor-permeable membrane and a vapor-impermeable membrane). Data on clothing insulation in a dry condition ($10^{\circ}C$) and a wet condition ($10^{\circ}C$, 40% R.H.), evaporative resistance ($34^{\circ}C$, 40% R.H., and $10^{\circ}C$, 40% R.H.), and microclimate vapor pressure were collected and analyzed. According to the results, the thermal insulation of the experimental garment system ranged 1.27~1.40 in the dry condition and 0.40~0.89 in the wet condition at $10^{\circ}C$. Evaporative resistance ranged $41{\sim}525m^2Pa/W$. A decrease in thermal insulation by wetting underwear ranged 31~67% in the cold condition ($10^{\circ}C$). The breathability of the outer garment influenced the decrease in thermal insulation by wetting. The type of underwear fiber influenced the decrease in thermal insulation only when it was used with breathable outerwear. The vapor-permeable outerwear sample with polyester underwear (P_Perm) showed a larger decrease in insulation than that with wool (W_Perm). The evaporative resistance of the vapor-permeable ensemble showed no effect of underwear in the warm condition ($34^{\circ}C$), but polyester underwear showed lower evaporative resistance than wool in the cold condition ($10^{\circ}C$). The vapor-impermeable ensemble showed no difference in evaporative resistance between polyester underwear and wool underwear in both conditions. Future research should consider various clothing ensemble combinations and environmental conditions and evaluate wear comfort by using human subjects.

• Elastomers and Composites
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• 제38권2호
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• pp.147-156
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• 2003

풀러렌[$C_{60},\;C_{70}$]을 benzoylperoxide, trichloroisocyanuric acid, methyltrioxorhenium(VII), iodosobenzene 그리고 phosphorous pentoxide 등의 산화제를 사용하여 상온, 초음파 조건에서 풀러렌 산화물을 제조하였다. MALDI-TOF MS, UV-VIS 그리고 HPLC를 사용하여 분석한 결과 생성된 풀러렌 산화물은 [$C_{60}(O)_n$], ($n=1{\sim}3$ 또는 n=1)과 [$C_{70}(O)_n$], ($n=1{\sim}2$ 또는 n=1)임을 알 수 있었다. 한편, 동일한 실험 조건에서 $C_{60}$ 반응속도는 $C_{70}$ 보다 높았다.

• 동력기계공학회지
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• 제10권2호
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• pp.111-116
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• 2006

Tribologcal property of the ceramics used in severe condition was investigated and both $Al_2O_3$ ball and Al/SiC composite made by thermal spray process[TSP] were used as a specimen in this study. Four kinds of material couple in ball and disk specimens were tested in the dry condition by using ball-on-disk type tribo-tester. Friction coefficient, surface roughness, wear rate, and photograph of the worn surface were investigated. Generally, High SiC contents[$40{\sim}50%$] specimens showed very low friction coefficient below 0.05 and little wear rate in dry condition. And also, low SiC contents[0%] specimens showed a moderate wear rate and high coefficient of friction at the same condition.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.1219-1224
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• 2001

In this study, concrete what plenty of fly ash used as binder is left in three condition humid condition($35^{\circ}C$), normal condition($20^{\circ}C$) and cold condition($5^{\circ}C$). Fly ash concrete is tested in fresh properties and early strength. The result of tests could give the decisive factor of form side's stripping time. The purpose of this study is presenting the stripping time data to help the construction work. The result of this study is below. 1. The plain concrete specimen in humid condition developed high strength before 5 days, then strength development is declined. 10 day strength of plain specimen is smaller than the normal condition specimen's. 2. The strength of the concrete which plenty of fly ash used is more developed than the concrete in normal condition. It says that fly ash concrete is useful in the humid condition. 3. As fly ash substitution rate is downsizing and outdoor temperature degree is low, form stripping times is getting shorter.

• 한국진공학회지
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• 제5권3호
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• pp.229-238
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• 1996

The electromigration phenomena and the characterizations of the conductor lifetime (Time-To-Failure, TTF) in Al-1%Si thin film interconnections under D.C. and Pulsed D.C. conditions were investigated . Meander type test patterns were fabricated with the dimensions of 21080$mu \textrm{m}$ length, 3$\mu\textrm{m}$ width, 0.7$\mu\textrm{m}$ thickness and the 0.1$\mu\textrm{m}$/0.8$\mu\textrm{m}$($SiO_2$/PSG)dielectric overlayer. The current densities of $2 \times10^6 A/\textrm{cm}^2$ and $1 \times10^7 A/\textrm{cm}^2$ were stressed in Al-1%Si thin film interconnection s under a D.C. condition. The peak current densities of $2 \times10^6 A/\textrm{cm}^2$ and $1 \times10^7 A/\textrm{cm}^2$ were also applied under a Pulsed D.C. condition at frequencies of 200KHz, 800KHz, 1MHz, and 4MHz with the duty factor of 0.5. THe time-to-failure under a Pulsed D.C.($TTF_{pulsed D.C}$) was appeared to be larger than that under a D.C. condition. It was found that the TTF under both a D.C. and a Pulsed D.C. condition. It was found that the TTF under both a D.C. and a Pulsed D.C. condition largely depends upon the appiled current densities respectively . This can be explained by a relaxation mechanism view due to a duty cycle under a Pulsed D.C. related to the wave on off. The relaxation phenomena during the pulsed off period result in the decayof excess vacancies generated in the Al-1%Si thin film interconnections because of the electrical and mechanical stress gradient . Hillocks and voids formed by an electromigration were observed by using a SEM (Scanning Electron Microscopy).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.469-472
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• 2003

The nematic liquid crystal (NLC) aligning capabilities using a-C:H thin film deposited at the three kinds of rf bias condition were investigated. A high pretilt angle of about $11^{\circ}$ by the ion beam alignment method was observed on the a-C:H thin film (polymer-like carbon) deposited at 1W rf bias condition, and the low pretilt angle of the NLC was observed on the a-C:H thin film(diamond-like carbon) deposited at rf 30W and 60W bias condition. Consequently, the high NLC pretilt angle and the good aligning capabilities of LC alignment by the IB alignment method on the a-C:H thin film deposited at 1W rf bisa condition can be achieved.