• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.280-281
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• 2006

Cordierite 결정상을 LTCC공정 적용온도에서 소결하기 위한 glass 조성을 조사하였다. 상용의 glass중 Pb-B-Si-O계, Na-Zn-B-O계 glass를 선택하였고 LTCC용 기판소재로서의 가능성을 확인하기 위하여 저온 동시소성이 가능한 소결온도인 $850^{\circ}C$와 $1000^{\circ}C$ 사이에서 소재의 소결실험을 진행하였다. 소결조건에 따른 상변화, 유전특성을 확인한 결과 glass상, 결정상, 용융에 의한 glass상으로 상의 변화가 있음을 확인 할 수 있었으며, LTCC 소결 조건에서 Pb-B-Si-O계 glass의 경우 2.9~3.7의 낮은 유전율과 0.0027의 우수한 dielectric loss, 내전압 특성을 가지고 있음을 확인하였다.

• Journal of Bio-Environment Control
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• v.7 no.2
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• pp.109-115
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• 1998

This study was conducted to evaluate the growth and flowering responses of Eustoma grandiflorum cv. Azmasul, Azmahoon and Azmazo influenced by duration of storage at 1$0^{\circ}C$ of seedlings raised in warm season. The plants after cold treatment were cultivated in a glasshouse under natural day length with the minimum temperature of 12$^{\circ}C$. The stem thickness and number of leaves of Azmasul and Azmahoon were not affected by duration of cold treatment However, plant height, internode length fresh and. dry weights were significantly increased in the four-week treatment. In addition, four-week treatment increased flower weight and width. Bays to flowering of Azmasul and Azmahoon in four-week treatment were shortened by 20 days compared to the control or two-week treatment. Shoot growth and flower Qualify of Azmazo under the four-week treatment were promoted. Four-week treatment reduced the days to flowering of Azmazo by 31 and 36 days compared to the control and two-week treatment. The results of this study show that optimum duration for storage at l$0^{\circ}C$ for seedlings of Ewtoma grandiflorum cv Azmasul. Azmahoon and Azmazo grown in warm season is four weeks.

• Journal of Bio-Environment Control
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• v.21 no.1
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• pp.33-38
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• 2012

Growth response of 'Sambokkul' watermelon grafted onto different rootstocks including 4 $Citrullus$ rootstocks and 3 other cucurbitaceous rootstocks was evaluated at two different temperature regimes. Significant reduction in plant growth rate was observed in plants grown at low temperatures (LT) as compared to those grown at normal or optimal temperatures. Relative growth reduction were 40~47% for vine length, 39~51% for total leaf area, 38~59% for shoot fresh weight, and 57~87% for plant dry weight, respectively. Watermelon rootstock PI 482322 showed comparable plant growth as the most popular rootstock 'Shintozwa' even at LT. 'Sambokkul' watermelon grafted onto watermelon hybrids, 'PI 271969 ${\times}$ PI 296341' and 'PI 271769 ${\times}$ Calhoun Gray', showed comparable plant growth as 'FR Dantos' bottle gourd rootstock. Index of growth ability at LT, which was calculated on the basis of reduced rate of vine length, dry weight and leaf area, was significantly high in $C.$ $martinezii$, 'Shintozwa', PI 482322, and 'PI 271769 ${\times}$ PI 296341' rootstocks (50% or higher) and low in own-rooted 'Sambokkul' or in watermelon plants on 'Knight' rootstock. Watermelon hybrids, 'PI 271969 ${\times}$ PI 296341' and 'PI 271769 ${\times}$ Calhoun Gray', showed better or at least comparable growth at low temperatures as compared to 'FR Dantos', confirming the feasibility of using watermelon rootstocks even in low temperature conditions.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.732-739
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• 2013

'Akihime' plums picked at mature stage (50-70% red coloration of the fruit skin) were stored at $1^{\circ}C$ under air or controlled atmosphere (CA) storage regime as following 3% $O_2$ + 1, 3, 5, and 7% $CO_2$ for 50 days for the purpose of assessing the effect of CA storage on the maintenance of fruit quality and the reduction of chilling injury. Fruits stored under CA storage regime showed reduced respiration as well as ethylene production rates compared to the fruits stored in air. Quality attributes including weight loss, Hunter 'a' values, soluble solids content, titratable acidity, and firmness showed smallest changes in fruits stored under CA conditions except for 3% $O_2$ + 7% $CO_2$. High incidence of physiological disorders including chilling injury, flesh browning, and decay were found in fruits stored under both air and CA of 3% $O_2$ + 7% $CO_2$. In our study, the CA storage regime of 3% $O_2$ + 5% $CO_2$ was found the most effective for maintaining overall fruit qualities of 'Akihime' plums produced in Korea, also delayed the development of chilling injury including lack of juiciness and flesh browning. From the results, storage at 3% $O_2$ + 5% $CO_2$ was selected as an optimal condition of 'Akihime' plum for extending storage life up to 50 days at $1^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.456-460
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• 2004

Effects of sigma factor (${\sigma}^{B}$) on biofilm formation in Listeria monocytogenes 10403S and ${\sigma}^{B}-deficient$ sigB null mutant were studied under high osmotic and low temperature conditions. In brain heart infusion (BHI) medium containing 6% NaCl, wild type 10403S and ${\sigma}^{B}-deficient$sigB null mutant formed biofilms of $6.83{\pm}0.38\;and\;5.33{\pm}0.45\;log\;cfu/cm^{2}$, respectively. L. monocytogenes 10403S in BHI medium containing 6% NaCl formed 4.7 times larger biofilm than without NaCl. Culture of L. monocytogenes 10403S and sigB null mutant at $4^{\circ}C$ did not show any significant differences in biofilm formation. The results suggest biofilm formation is activated by ${\sigma}^{B}$ and NaCl, whereas not affected by low temperature stress in L. monocytogenes 10403S. More studies are necessary to determine biofilm formation mechanism in osmotolerant L. monocytogenes.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.283-287
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• 2004

Persimmons suffer from such physiological disorders as flesh softening, peel blackening, and flesh browning, which occur rapidly particularly when exposed to ambient temperature after storage at low temperature, In this study causes of these disorders were examined in terms of respiration and ethylene production of the fruits. Jelly-like flesh softening, considered as symptom of chilling injury, rapidly developed within 3 days of exposure to ambient temperature without modified atmosphere (MA) packaging after low temperature storage. Disorder development was more suppressed at $30^{\circ}C$ than at $20^{\circ}C$; such temperature dependence is closely connected to ethylene production rate of fruits at both temperatures. Inhibition of ethylene production through MA packaging effectively reduced disorder development, which indicates ethylene production is closely related to jelly-like flesh softening disorder. Development of black-staining on peels occurs in fruits exposed directly to ambient temperature, but not in those packaged with thick PE-film. Flesh browning developed only under anaerobic respiration condition of high temperature and MA packaging with thick PE film, and occurred at quick reduction of available oxygen inside MA package at high temperature.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.1
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• pp.27-33
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• 2023

An optimized design of the transportation insulated box must be considered to control the thermal damage in order to maintain the fresh condition for temperature-sensitive medicine and frozen food safety. The inside temperature of the insulated box is a natural convection enclosure state, thermal stratification naturally occurs as time passes in case of with outside heat load. The latent heat material (LHM) placement inside the box maintains the target temperature of the product for temperature fluctuations during transport, and LHM application is a common and efficient method. In this work, inside temperature stratification in an insulated box depending on the LHM pack position is numerically simulated and experimented. The insulated box is made up of vacuum insulation panel (VIP), and LHM modules are placed over six faces inside the box, with the same weight. The temperature curves for 72 hrs as experiment results clearly show the temperature stratification in the upper, middle, and lower at the LHM melting time region. However, the temperature stratification state is uniformly changed in accordance with the condition of the upper and lower placement weight of the LHM pack. And also, the temperature uniformity by changed placement weight of LHM has an effect on maintaining time for target air temperature inside the box. These results provide information on the optimized design of the insulated box with LHM.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.35-36
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• 2002

High temperature super conducting(HTS) cable system for power transmission are under development that will be cooled by sub-cooled liquid nitrogen to provide cooling of the cable and termination. The target of the development during the first 3-years stage is 22.9kV/50MVA class and 30m length cold dielectric type 3-phase power cable. The essential features of the HTS cable cryogenic system and performance conditions for the design of power cable will be discussed.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05b
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• pp.205-209
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• 1996

원자로 입구노즐에서 원자로 냉각재 펌프에 의한 맥동압력 준위를 원자로 하향통로와 저온 관을 상관시켜 예측하는 방법에 관하여 분석하였다. 원자로 하향통로에서의 맥동압력은 원자로 내부구조물의 건전성 평가에 쓰이는 중요한 인자로 이 값을 정확히 구하기 위해서는 경계조건인 입구노즐에서의 맥동압력을 정확히 예측해야 한다. 이를 위해 원자로 하향통로와 저온관을 상관시켜 원자로 입구노즐에서의 펌프에 의한 맥동압력 준위를 계산하였으며 Palo Verde Unit 1의 실험치와 비교 분석하였다. 분석 결과, 제시된 맥동압력 준위 예측모델은 500℉의 경우 비교적 잘 일치하였으나, 565℉의 경우 상당한 차이가 있었으므로 추가적인 검토 및 수정 작업이 요구된다.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 1999.02a
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• pp.14-17
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• 1999

Four designed $Nb_{3}$Sn superconductors have been fabricated in order to investigate the effect of pre-heat treatment for internal tin process. 3 types of sub-elements and 2 types of Sn reservers were fabricated. Diffusion of Sn is better in the strand divided Sn equally than in the strand had one large Sn reserver during pre heat-treatment.