• 한국식품영양학회지
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• 제11권5호
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• pp.536-541
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• 1998

This study was carried out to investigate the changes of characteristics of myofibrillar protein for the vacuum chilled, the air frozen or the rechilled Holstein beef loin. The vacuum chilled beef was stored at 1$^{\circ}C$ and the air frozen beef was stored at -20$^{\circ}C$ for 60 days. The rechilled beef was restored for 3 days at 1$^{\circ}C$ by using the vacuum chilled or the air frozen beef. Myofibrillar protein extractability, 30,000 dalton component content and Mg-ATP ase activity for the vacuum chilled beef were higher than those of the air frozen beef. Each parameters increased significantly for the vacuum chilled beef after the 20 days storage, but there was no significant difference for the vacuum chilled beef after the 20 days storage, but there was no significant difference for the air frozen beef during the 60 days storage. By the rechilling process, myofibrillar protein extractability of the vacuum chilled and the frozen beef were not significant difference. The 30,000 dalton component of the vacuum chilled beef was showed not significant increment by rechilling, but the frozen beef was showed significant increment by rechilling. The Mg-ATPase activity of myofibrillar protein of the vacuum chilled beef was not changes by rechilling, but the frozen beef after the 20 days storage was significant increment by rechilling.

• 한국축산식품학회지
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• 제18권3호
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• pp.216-223
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• 1998

This study was conducted to investigate the effects of the tenderness for the vacuum chilled, the air-frozen or the rechilled Holstein beef loin. The vacuum packaged beef was stored at 1$^{\circ}C$ and the air-packaged beef was stored at -20$^{\circ}C$ for 60 days. The rechilled beef was restored for 3 days at 1$^{\circ}C$ by using the vacuum chilled or the air-frozen beef. Hardness and chewiness of the vacuum chilled beef were better than those of the air-frozen beef. Hardness and chewiness were improved significantly(p＜0.05) after the 40 days storage for the vacuum chilled beef, but there was no significant improvement for the air-frozen beef during the 60 days storage. By the rechilling process, tenderness and myofibrillar fragmentation index of the vacuum chilled and air-frozen beef improved. Especially those were improved significantly(p＜0.05) in the vacuum chilled beef after the 20 days storage, and in the air-frozen beef after the 40 and 60 days storage.

• 한국가금학회지
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• 제24권1호
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• pp.17-28
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• 1997

This experiment was carried out to investigate the effects of different chilling and packing methods on physico-chernical properties of cold-stored chicken breast and thigh meats. Dehoned chicken breast and thigh meats were chilled either air spray or ice-water immersion method. The chilled meats were either vacuum packed or atmosphere packed, and stored at -2˚C for 1, 3, 7, 11, 15, and 20 days. The pH of both immersion chilled meats and vacuum packed meats were higher than those of their counterparts(P<0.05). The pH of atmosphere packed meats increased as the storage period extended. The moisture contents of vacuum packed meats were remarkably higher than those of atmosphere packed meats. The pH of all treatments decreased as the storage period extended. The shear values of air spray chilled and vacuum packed breast meats were significantly higher than immersion chilled and vacuum packed ones. However, immersion chilled and atmosphere packed breast meats were significantly higher than those of air spray chilled and atmosphere packed breast meats. The shear values of immersion chilled and vacuum packed thigh meats were significantly higher than those of immersion chilled and vacuum packed thigh meats. In atmosphere packed thigh meats, air spray chilling method showed higher shear values than those of immersion chilled thigh meats. In thigh muscle, tenderness values tended to decrease as the storage period extended(P<0.05). Contents of water soluble proteins of vacuum packed and air spray chilled breast and thigh meats were higher than those of their counterparts as the storage period extended(P<0.05). The contents of water soluble proteins significantly decreased as the storage period extended. Salt soluble proteins of atmosphere packed breast and thigh meats were remarkably higher than those of vacuum packed ones(P<0.05). Total lipid contents of atmosphere packed and air spray chilled breast and thigh meats were higher than those of atmosphere packed and immersion chilled meats as the storage period extended. The vacuum packed meats were significantly higher in total lipid contents than those of atmosphere packed meats. The storage period decreased the total lipid contents of cold chicken, Major fatty acids in cold-stored chicken were oleic, palmitic, linoleic and stearic acids, regardless of chilling method. Unsaturated fatty acids of all treatments decreased, but saturated fatty acids increased as the storage period extended.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.164-169
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• 2001

There is a chilled ceiling panel which carries out the air conditioning by radiation and convection between the room and cold ceiling panel surface. In order to verify heat transfer characteristics between them in cooling system with radiant chilled ceiling panel, analytical and experimental studies were performed for various design and operating parameters such as tube space and diameter, inlet water temperature, mass flow rate, cooling load, and so on. In this study, we found that the tube space and inlet water temperature were more important elements than the tube diameter and water flow rate for the performance of radiant chilled ceiling panel. The cooling capacity of the radiant chilled ceiling panel had the maximum value of $65W/m^{2}$ because the highest cooling capacity was limited by the condensation on the panel surface. The results of comparison between numerical analysis and experiment showed a resonable agreement qualitatively, especially for low cooling capacity.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2007년도 춘계학술논문 발표대회
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• pp.43-46
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• 2007

This study dealt with the influence of the replacement ratio of rapidly-chilled steel slag on fluidity and compressive strength of unsaturated polyester polymer concretes. The rapidly-chilled steel slag used in this study, a by-product which is produced by refining pig iron during the manufacture of steel, was controled by a air-jet method which rapidly cools substance melted at a high temperature. Experimental results show that fluidity and compressive strength of unsaturated polyester polymer concretes increase with increasing replacement ratio of rapidly-chilled steel slag. Use of rapidly-chilled steel slag was found to be effective for improving fluidity and compressive strength of rapidly-chilled steel slag.

• 설비공학논문집
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• 제25권5호
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• pp.255-260
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• 2013

Since a chilled beam system can reduce the conveyance energy for air conditioning and has many advantages in terms of constructability and indoor environment, its supply has been rapidly expanding mainly in Europe. For this chilled beam system to be effectively available in Korea, a product suitable for the domestic climatic environment and HVAC system operating conditions needs to be developed. Also, domestic products need to have an edge in cost competitiveness compared to overseas products. In this study, the induction structure of a chilled beam is deduced and an analysis on the induction performance is carried out while the chilled beam system that meets domestic situations is in the process of development.

• 식품보건융합연구
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• 제8권3호
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• pp.1-9
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• 2022

Purpose-Meat plays an important role in the Chinese daily diet, however, due to the spread of COVID-19, food supply and safety have become a major concern. The safety and health features of chilled fresh meat have attracted the attention of consumers. To study consumers' purchasing behavior and willingness to pay for chilled meat under the influence of the epidemic. Research methodology- The data were obtained by questionnaire survey, major issues include consumers' meat consumption habits in the wake of the COVID-19 and their awareness of meat product quality labels. In addition, the gender, age, family income, and other basic personal information of the interviewees were also counted. Based on the binary Logit regression method, we study consumers' purchasing behavior and willingness to pay for chilled meat under different demographic characteristics. Results-The results showed that brand and quality certification are important factors influencing purchases. In addition, the presence of children under the age of 12 in the household and the level of income and education also influence consumers' purchase intention of the chilled fresh meat. However, mart promotions and city ratings can significantly lower consumers' propensity to buy the chilled fresh meat. Apart from this, such factors as gender, age, and living conditions have no significant influence on consumers' purchase of chilled fresh meat.

• 한국유체기계학회 논문집
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• 제17권5호
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• pp.11-18
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• 2014

Chilled Beam system is the kind of water-air system which reduces the conveyance energy for air conditioning as well as allows efficient installation and comfortable indoor environment, and has been increasingly popular mainly in Europe. To effectively install such Chilled Beam system domestically, it is necessary to develop the product considering domestic climatic condition and the requirements for air conditioning system, and particularly the way to deal with condensation during operation of cooling system in summer shall be provided. In this study, the optimal design on induction structure of Chilled Beam unit was carried out through a numerical method, and the performance test for the prototype of unit was conducted in a real-scale experiment facilities of Chilled Beam unit. While the flowrate of 1st air is 101.3 CMH, the pressure in pressure chamber is 158.7 Pa and the cooling capacities of 1st air side and 2nd air side are 498.1 W and 709.5 W respectively.

• 한국식품과학회지
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• 제23권3호
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• pp.379-387
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• 1991

저온 유통과정에 있는 우육에 유기산(아세트산, 시트르산, 락트산)을 처리하여 저온 보존기간에 따른 일반세균수, 부패취와 점질물의 생성, pH변화 등의 물리적, 세균학적인 실험을 대조군과 비교하여 실시하였으며 유기산 처리에 따른 냉장우육의 저장성을 파악하였다. 우육의 저온 보존기간에 따른 시료 처리군별 부패취 및 점질물 생성시기는 대조군에서 6일째에 세균수 $1.8{\times}10^7/cm^2$일 때 부패취를 발생하였고 7일째에 세균수 $6.1{\times}10^7/cm^2$일 때 점질물을 생성하였다. 유기산 처리군의 경우 $1{\sim}4%$ 모든 처리구에서 세균수 $0.8{\times}10^7/cm^2$일 때 부패취를 발생하였으며 1% 처리구에서는 대조군보다 1일, 2%에서는 2일, 3%에서는 3일, 4%에서는 5일이 늦어졌다. 또한 점질물 생성시기는 $1{\sim}3%$ 처리구에서 부패취 발생시기보다 2일 늦게 생성되었으며 이 때의 세균수는 $1{\sim}2%$ 처리구에서 $6.0{\times}10^7/cm^2$ 이상, 3% 처리구에서는 $2.0{\times}10^7/cm^2$ 이상이었다. 우육의 저장성을 부패취를 기준을 할 때 대조군은 $4^{\circ}C$에서 5일, 유기산 처리구는 1%에서 6일, 2%에서 7일, 3%에서 8일, 4%에서 10일이었다. 저온 보존우육의 pH변화는 시료처리 초기에 대조군에서 pH5.5를, 유기산 처리군은 1%, 처리구에서 $pH5.3{\sim}5.4$를, $2{\sim}3%$, 처리구에서 각각 pH5.2를, 4% 처리구에서는 아세트산이 pH4.9, 시트르산과 락트산이 각각 5.0을 보임으로써 대조군에 비해 pH가 $0.2{\sim}0.6$이나 더 낮았다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2007년도 추계 학술논문 발표대회
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• pp.75-78
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• 2007

The steel slag, a by-product which is produced by refining pig iron during the manufacture of steel, is mainly used as road materials after aging. It is necessary to age steel slag for long time in air because the reaction with water and free-CaO in steel slag could make the expansion of volume. This problem prevents steel slag from being used as aggregate for concrete. However, steel slag used in this study was controled by a air-jet method which rapidly cools substance melted at a high temperature. The rapidly-chilled method would prevent from generation of free-CaO in steel slag. Also, Molten steel slag rapidly-chilled by air in high speed becomes a fine aggregate of nearly spherical shape. This study dealt with the influence of the using rate of rapidly-chilled steel slag and polymer resin on fluidity of polymer concrete, as a results Since RCSS has spherical shape and high density, up to replacement ratio of 100%, increases concrete fluidity under same polymer content and decrease polymer content in order to secure the same fluidity