• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.3
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• pp.177-182
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• 2004

A chill unit has been used to estimate chilling requirement for dormancy release and risk of freezing damage. A system that calculates chill units was developed to obtain site-specific estimates of dormancy release date for grapes and evaluated in Baekgu myun near Kimje City, Chunbuk, Korea from September 2002 to March 2003. The system utilized daily minimum and maximum temperature maps generated from spatial interpolation with temperature correction for topography. Hourly temperature was temporally interpolated from the daily data using a sine-exponential equation (Patron and Logan, 1981). Hourly chill units were determined from sigmoid, reverse sigmoid, and negatively increasing sigmoid functions based on temperature ranges and summed for 24 h. Cumulative daily chill units obtained from measurements did not increase until 20 October 2002, which was used as a start date for accumulation to estimate the dormancy release date. As a result, a map of dormancy release date in the study area was generated, assuming 800 chill units as a threshold for the chilling requirement. The chill unit accumulation system, implemented using Microsoft Visual Basic and C++ (Microsoft, Redmond, WA, USA), runs in the Windows environment with ArcView (ESRl Inc., Redlands, CA, USA).

• Korean Journal of Materials Research
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• v.16 no.11
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• pp.698-704
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• 2006

In this study, the effect of chill layers occurred in shot sleeve on the molten metal filling was analyzed through computer simulation. The behavior of chill layers with temperature variation of shot sleeve set from 200 to $280^{\circ}C$ was also investigated. The simulation results showed the chill layers set in the in-gates during the injection process change the main filling direction and cause turbulent flow pattern, resulting in porosities inside the castings. The amount of chill layers with the increasing temperature of shot sleeve was considerably reduced. Particularly, at the setting temperature of $280^{\circ}C$ by heat control unit, the biggest reduction in chill layers, excellent trimmed surface and the highest density were achieved, suggesting that as the optimal sleeve condition in aluminum high pressure diecasting, especially for highly complex parts like valve body.

• Journal of Korea Foundry Society
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• v.25 no.4
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• pp.168-172
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• 2005

In this study, the effects of chill layers occurred in shot sleeve on the molten metal filling were analyzed through computer simulation and the behavior of chill layers with temperature variation of shot sleeve set from 200 to $280^{\circ}C$ was also investigated. The simulation results showed the chill layers set in the in-gates during the injection process change the main filling direction and cause turbulent flow pattern, resulting in porosities inside the castings. The amount of chill layers with the increasing temperature of shot sleeve was considerably reduced. And particularly, at the setting temperature of $280^{\circ}C$ by heat control unit, the big reduction in chill layers, excellent trimmed surface and the highest densification were achieved, suggesting that as the optimal sleeve condition in diecasting, especially for the highly complex parts like valve body.

• Korean journal of food and cookery science
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• v.14 no.4
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• pp.358-366
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• 1998

To meet the demand for high quality of foods with the expanded implementation of foodservice into kindergarten, and to make the efficient use of resources, the necessity of introducing central production unit with cook/chill system into kindergarten foodservice is getting increased. The purpose of this study were to develop standardized recipe applicable to cook/chill system for kindergarten foodservice and to evaluate the microbial and sensory quality. For quantitty production of cook/chill system in kindergarten foodservice, Various Bulkogis were selected as menu items. The followings are summary of the results： 1. Standard recipes to produce Various Bulkogis(Broiled Sliced Meat with Sauce) for cook/chill system have been developed. 2. The microbial quality of Various Bulkogis during 10 days chilled storage was very good. And in this experiment, the stability of storage of standard recipes of Various Bulkogis at cook/chill system was proved for 10 days. 3. All of the items of sensory evaluation of Bulkogis has no significance between the first day and the third day of storage, except the color of Pork Bulkogi (P<0.05).

• Korean journal of food and cookery science
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• v.14 no.4
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• pp.348-357
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• 1998

To meet the demand for high quality of foods with the expanded implementation of foodservice into kindergarten, and to make the efficient use of resources, the necessity of introducing central production unit with cook/chill system into kindergarten foodservice is getting increased. The purpose of this study were to develop standardized recipe applicable to cook/chill system for kindergarten foodservice and to evaluate the microbial and sensory quality. For quantitty production of cook/chill system in kindergarten foodservice, Korean traditional starch foods were selected as menu items. The followings are summary of the results： 1. Standard recipes to produce Various Boiled Rice (Boriebap and Yackbap) and Rice Cake (Chapsal-pat-sirutuk) for cook/chill system have been developed. 2. The microbial quality of Boribap, Yackbap and Chapsal-pat-sirutuk during 10 days chilled storage was very excellent. And in this experiment, the stability of storage of standard recipes of Boribap, Yackbap and Chapsal-pat-sirutuk at cook/chill system was proved for 10 days. 3. In the result of sensory evaluation, apperance of Boribap was decreased significantly on the third day of storage (p<0.005). The rest of the item of sensory evaluation of Boribap has no significance between the first day and the third day of storage. The tenderness (p＜0.05) and gelatinousness (p<0.005) of Yackbap had been rated high significantly in the third day of storage than the first day of storage. The rest of the item of sensory evaluation of Boribap has no significance between the first day and the third day of storage. The color and chewiness of Chapsal-pat-sirutuk was decreased significantly on the third day of storage (p＜0.05). The rest of the item of sensory evaluation of Chapsal-pat-sirutuk has no significance between the first day and the third day of storage.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2003.09a
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• pp.77-81
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• 2003

지구온난화에 따른 "춥지 않은 겨울" 현상 속에서도 온대과수의 동해발생 건수는 오히려 증가하는 기현상이 보고되고 있다 (원예연구소, 2003). 휴면중인 과수는 내동성이 매우 크지만 겨울에서 봄으로 이행하면서 점차 약해진다. 내동성이 매우 큰 사과 품종 Haralson의 경우 한 겨울에 -50도에서도 생존이 가능하지만 봄에는 치사온도가 -8도로 급상승하는데 (Faust, 1989), 그 이유는 혹한에 적응해온 추운 지역 토착품종들은 생육기간을 확보하기 위해 기온이 상승하면 바로 휴면을 깨고 생장을 시작하는 습성을 갖고 있기 때문이다.(중략) 때문이다.(중략)

• Food Science of Animal Resources
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• v.18 no.4
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• pp.322-331
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• 1998

Good temperature control in the chill chain is imperative for maintaining safety and quality of the fresh meat. Therefore, the actual state of temperature or relative humidity histories of fresh meat product from carcass chill room to retail shop and the temperatures of chill and freezing rooms at local butcher shops were monitored by means of data loggers. The relative humidity and air temperature in carcass chill room were between 86 and 98%, and -3 and 0$^{\circ}C$, respectively. The surface temperatures of boxed beef measured in winter, when the outside air temperature was measured between -2 and -5$^{\circ}C$, were recorded between 1 and 3$^{\circ}C$, although transport vehicle switched off the chilling unit during transportation, However, the inside temperatures of chill transport vehicle measured in summer, when the transport time was prolonged to maximum 8 hrs, were raised to 10 to 15$^{\circ}C$, in worst case up to 25$^{\circ}C$. In that case, however, the inside temperature of boxed beef was maintained generally lower than 5$^{circ}C$ as the loading and unloading were finished within 30 min. The storage temperatures for meat in the subfreezing room, at which the butcher shops in local market are used to set to facilitate the thin slicing of meat, were measured between -2 and -8$^{\circ}C$. Furthermore, the temperatures of storage room for vacuum packaged meat in the chilled meat retail shops were maintained generally between 0 and +2$^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1095-1101
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• 2001

Spinach was minimally processed into the unseasoned side dish to be used for Korean food service industry, using the techniques of cook-chill and sous vide. Spinach was blanched at 10$0^{\circ}C$ for 6 minutes, vacuum-packaged in the unit of 500 g by plastic film of low gas permeability, pasteurized at 9$0^{\circ}C$ and then cooled rapidly at 3$^{\circ}C$. The chilled products were then stored at 3 and 1$0^{\circ}C$ with measurement in their quality. Six log cycle (6D) inactivation of Listeria monocytogenes and 13 log (13D) thermal destruction of Streptococcus faecalis were compared as two pasteurization conditions, which corresponded to heating for 22.8 and 30.0 minutes at 9$0^{\circ}C$, respectively. Milder heat processing based on 6D process of L monocytogenes gave better quality of color, texture, ascorbic acid and chlorophyll than the conditions of 13D process of S. faecalis. Any microbial growth in total aerobic, psychrophilic and anaerobic bacteria was not observed until 8 days at 1$0^{\circ}C$ and 14 days at 3$^{\circ}C$, which might be regarded as strict guidelines of shelf life. Storage times based on the changes in physical and chemical quality were longer than those based on strict microbial quality in case of the products pasteurized by 6D process of L. monocytogenes. The seasoned vegetables prepared from sous vide processed spinach were found to be inferior in sensory quality to those from freshly blanched one.

• The Korean Journal of Community Living Science
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• v.25 no.4
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• pp.557-566
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• 2014

This study examines he trend in the development of protective clothing for pesticide spraying based on materials with domestic patents and proposes pesticide protection clothing using a cooling blower unit effective for reducing heat stress in pesticide spraying. There was a total of 54 domestic patents on protective clothing related to pesticide spraying, reflecting a sharp increase based on the increasing demand for protective clothing since 2000. Protective clothing with a lower level of heat stress as the core technology accounted for 35.2% of these patents, and recent years have witnessed the increased development of protective clothing supplying cold air to the interior of the clothing through a separate device. However, this may cause some inconvenience in the activity of farmers. Therefore, this study proposes a lightweight cooling blower unit that does not hinder the user's appearance and activity. In the cooling blower unit, contaminated air from outside is purified through a filter and cools down as it passes a cooling device with refrigerant in the copper pipe. This chilled air is supplied to the interior of the clothing through a bidirectional inhaling blower. The proposed protective clothing is an overall with raglan sleeves. Its chill injection site has an area where the most conspicuous change in temperature is selected, and at the back, there is a large pocket for a cooling blower unit.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.213-220
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• 2009

In order to predict the risk of freeze injury for 'Changhowon Hwangdo' peach trees, we used the dormancy depth (i.e., the daily chill unit accumulation during the overwintering period) as a proxy for the short-term, physiological tolerance to freezing temperatures. A Chill-days model was employed and its parameters such as base temperature and chilling requirement were optimized for peach trees based on the 12 observational experiments during the 2008-2009 winter. The model predicted the flowering dates much closer to the observations than other models without considering dormancy depth, showing the strength of employing dormancy depth into consideration. To derive empirical equations for calculating the probabilistic freeze risk, the dormancy depth was then combined with the browning ratio and the budburst ratio of frozen peach fruit branches. Given the exact date and the predicted minimum temperature, the equations calculate the probability of freeze damages such as a failure in budburst or tissue browning. This method of employing dormancy depth in addition to freezing temperature would be useful in locating in advance the risky areas of freezing injury for peach trees production under the projected climate change.