• 한국식품조리과학회지
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• 제3권2호
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• pp.100-110
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• 1987

The effectiveness of hot thermal retention system which was being used in 3 general hospitals, A,B, and C in Seoul was evaluated in terms of time-temperature relationship. The results of the study were summrized as follows: 1) The serving temperature of steamed rice using insulated bowls were significantly higher than those of using no thermal support. 2) The serving temperatures of soup using insulated bowls were significantly higher than those of using no thermal support. 3) The serving temperatures of meat of fish dishes using insulated bowls as well as warmer cabinet were significantly higher than other groups such as using warmer cabinet only, using insulated bowls only, and using no thermal support. 4) However surveyed serving temperatures of meals using hot thermal retention system were not whthin the range of temperature criteria.

• 환경위생공학
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• 제11권3호
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• pp.63-68
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• 1996

This study was to discuss limiting factors influenced on the removal efficiencies of nitrogenous compounds investigated using the polypropyrene media which was to attach microorganism in order to apply the fixed-biofilm process. The main limiting factors are the hydraulic retention time (HRT), C/N ratio, $COD/NO_{3}-N$ ratio and temperature. The hydraulic retention time HRT were 6, 8, 10, 12 hrs and the C/N ratio range was 2.5-9.5. The $COD/NO_{3}-N$ ratio range was 3.2-21.9 and the temperature were 15, 20, 25, 30, $35^{\circ}C$, respectively. The results of this study are summerized as follows. 1. Hydraulic retention time (HRT) to obtain removal efficiencies of T-N higher than 85% had to be 10 hrs above. 2. The removal efficiencies of T-N decreased at C/N ratio from 6.2 to 4.8 in this anoxic-contact aeration system. 3. Denitrification rate decreased at $COD/NO$_{3}$-N$ ratio from 8.0 to 5.0 4. As temperature increased, removal efficiencies of T-N increased.

• Nutrition Research and Practice
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• 제6권2호
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• pp.126-131
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• 2012

The purpose of this study was to determine the effects of beverage temperature and composition on weight retention and fluid balance upon voluntary drinking following exercise induced-dehydration. Eight men who were not acclimated to heat participated in four randomly ordered testing sessions. In each session, the subjects ran on a treadmill in a chamber maintained at $37^{\circ}C$ without being supplied fluids until 2% body weight reduction was reached. After termination of exercise, they recovered for 90 min under ambient air conditions and received one of the following four test beverages: $10^{\circ}C$ water (10W), $10^{\circ}C$ sports drink (10S), $26^{\circ}C$ water (26W), and $26^{\circ}C$ sports drink (26S). They consumed the beverages ad libitum. The volume of beverage consumed and body weight were measured at 30, 60, and 90 min post-recovery. Blood samples were taken before and immediately after exercise as well as at the end of recovery in order to measure plasma parameters and electrolyte concentrations. We found that mean body weight decreased by 1.8-2.0% following exercise. No differences in mean arterial pressure, plasma volume, plasma osmolality, and blood electrolytes were observed among the conditions. Total beverage volumes consumed were $1,164{\pm}388$, $1,505{\pm}614$, $948{\pm}297$, and $1,239{\pm}401$ ml for 10W, 10S, 26W, and 26S respectively ($P$ > 0.05). Weight retention at the end of recovery from dehydration was highest in 10S ($1.3{\pm}0.7kg$) compared to 10W ($0.4{\pm}0.5kg$), 26W ($0.4{\pm}0.4kg$), and ($0.6{\pm}0.4kg$) ($P$ < 0.005). Based on these results, carbohydrate/electrolyte-containing beverages at cool temperature were the most favorable for consumption and weight retention compared to plain water and moderate temperature beverages.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.58-59
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• 2018

In this study, firing experiments were carried out to confirm the foamability of the expansive shale collected from the local area. When expansive shales are subjected to high temperature heat, gas is generated inside and voids are formed. Due to this phenomenon, shale is used as a raw material for lightweight aggregate. Experiments were carried out with different plastic temperature and residence time to find the appropriate plastic temperature for this expansive shale. As a result, the higher the plastic temperature, the more the surface viscosity increased and the gas generated inside were retained. Resulting in a number of internal voids. However, even if the plastic temperature or the medium temperature is high, it is confirmed that sufficient gas is not generated when the residence time is shortened.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 동계학술발표대회 논문집
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• pp.392-397
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• 2005

This study is investigated the supercooling improvement and the phase change temperature of the TMA clathrate compound including TMA(Tri-Methyl-Amine, ($(CH_3)_3N$) of 25 wt% with additive as a low temperature storage material at $6^{\circ}C$ and $-7^{\circ}C$ of heat source. The additive is ethanol of 0.1, 0.3 wt% and 0.5 wt%. The results showed that as the concentration of ethanol is increased, the phase change temperature, the degree of supercooling and the retention time of liquid phase are decreased. Especially, TMA 25 wt% clathrate compound with ethanol of 0.5wt% has the average of phase change temperature of $3.8^{\circ}C$, degree of supercooling of $0.9^{\circ}C$, $0.8^{\circ}C$ and retention time of liquid phase for 6, 5 minutes at $-6^{\circ}C$, $-7^{\circ}C$ of heat source. From the results of this study, TMA 25wt% clathrate compound with ethanol 0.5wt% showed supercooling repression effect.

• 대한전자공학회논문지SD
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• 제37권5호
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• pp.1-8
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• 2000

PZT seed에 의해 형성된 단결정립 PZT 박막을 이용하여 Pt/PZT/Pt 구조에서의 피로(fatigue) 및 정보 유지(data retention) 특성에 관하여 연구하였다. 피로 특성의 경우 1㎒의 주파수에서 ±10V의 square wave를 인가하여 측정한 결과 2×10/sup 11/ cycle 동안 전혀 특성의 변화가 관찰되지 않았으며, 정보 유지 능력의 경우 상온에서 30000초 동안 기억 상태의 변화가 없었으며, 고온에서의 retention 측정으로 계산된 활성화 에너지로부터 구한 상온에서의 20% 잔류분극간 감소를 보이는 시간은 6.6×10/sup 7/ 년이었다.

• 한국환경과학회지
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• 제31권11호
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• pp.901-910
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• 2022

The aim of this study was to investigate the amount (i.e., retention volume) and chemical composition of Natural volatile organic compounds (NVOCs) across different sites in a temperate forest. The three forest sites that were considered include riparian zones (site 1), streams (site 2), and densely-canopied areas (site 3). From May to October 2021, a mini pump was used to measure the collected NVOCs. These measurements were conducted once a month, from 10:30 am to 11:30 am; these times encompass peak visitation times. In the tree layers of the site 1 and 2, Quercus acuta was dominant, whereas Camellia japonica dominated their subtree layers. On the other hand, the tree layer of site 3 was dominated by Castanopsis sieboldii, whereas Camellia japonica dominated its subtree layer. The retention volume and chemical composition of NVOCs was as follows: benzaldehyde (107.528ppm), α-pinene (37.868ppm), linalool (16.258ppm), eucalyptol (14.818ppm), and sabinene hydrate (14.679ppm). In particular, the retention volume of benzaldehyde decreased as temperature increased. In contrast, the retention volume of α-pinene increased as the temperature increased. The differences in forest topography across the studies sites were in the following order: riparian area> forest area> stream area.

• Korean Chemical Engineering Research
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• 제44권1호
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• pp.35-39
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• 2006

본 실험에서는 모델 시스템으로써 PVP 수지에서 과당, 포도당과 같은 당 시료와 젖산, 아세트산과 같은 유기산을 사용하여 온도 변화에 따른 체류 시간의 변화 정도를 알아보았다. 펄스 시험을 사용하여 당 시료의 온도 변화에 따른 체류 시간 변화를 알아본 결과, 그 변화가 크지 않았다. PVP 수지는 일반적으로 당 분리에 사용되는 분리 수지가 아닌 사실에서 예측할 수 있듯이 현저히 떨어지는 분리능을 보였고, 온도 변화에 따른 분리능의 변화 또한 나타나지 않았다. 반면에, PVP 수지에서 유기산의 경우에는 상당한 변화를 보였다. 따라서, 유기산에 대한 정량적 흡착특성의 변화를 알아보기 위하여 $35^{\circ}C$, $65^{\circ}C$ 온도에서 전단 분석하여 그 차이를 확인하였다. 이러한 온도에 대한 흡착특성은 SMB(simulated moving bed)와 같은 대규모 크로마토그래피 공정에 이용될 수 있을 것으로 판단한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 추계학술대회 논문집 학회본부
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• pp.232-234
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• 1996

The self-refresh mode was introduced as method to reduce power dissipation in DRAM. Because the data retention time of DRAM cell decreases as the ambient temperature rises, the internal period in self-refresh mode must be limited by retention capability at the highest temperature in DRAM specification. Because of this, at room temperature($25^{\circ}C$) unnecessary power dissipation happens, If the period of self-refresh could be modulated as temperature, it is possible to reduce the self-refresh current. In this paper, new temperature detector circuit is suggested as this purpose.

• 한국식품저장유통학회지
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• 제4권1호
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• pp.33-38
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• 1997

In order to provide informations for designing packaging and storage condition of dry jujube (Zizyphus jujuba MILLER), moisture sorption isotherm was determined for temperatures of 20, 30 and 4$0^{\circ}C$, and quality changes were evaluated as function of temperature and water activity. Dry jujube at a given water activity showed higher equilibrium moisture content for lower temperature. Moisture isothem could be fitted by GAB model equation, giving higher C value, lower m0 and relatively constant k value with increase in temperature. Ascorbic acid was lost more highly at higher temperature and water activity, and showed negligible retention for whole range of water activity and temperature studied after 141 days. Browning increased with water activity up to 0.73 at 30 and 4$0^{\circ}C$. Dry jujube of high water activity had high L value in surface color, which represent brightness of surface color. Considering quality retention in the storage, dry jujube is desired to be dried to water activity of 0.42 and be stored at temperature below 3$0^{\circ}C$