• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.795-797
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• 2001

This paper presents an improved automatic vending machine for ices. Specially, the main topic of this paper is the development of moving parts for carrying ices out of a freezer. In general, carrying ices out of a vending machine causes much cool air losses. The developed vending machine reduces much cool air losses by the improvement of moving parts. Also the machine reduces many mechanical troubles caused by the freezing of mechanically moving parts.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.309-313
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• 2000

An experimental study was conducted to analyze the characteristics of the showcase refrigeration system during frosting and defrosting process. Test showcase was constructed with a cooling capacity of 3RT including 3 evaporators. The dynamic characteristics of the system under frosting and defrosting conditions were investigated. Refrigerant temperature and pressure of the system, dry bulb and wet bulb temperature of air passing through the evaporator, air flow rate and compressor power were measured.

• Journal of Species Research
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• 제8권2호
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• pp.215-224
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• 2019

We describe three feather mites recovered from a wood sandpiper Tringa glareola that was stored in a $-20^{\circ}C$ freezer at the Chungnam Wild Animal Rescue Center. These feather mites are reported for the first time in South Korea: Avenzoaria totani (Canestrini, 1978), Ingrassia veligera Oudemans, 1904 and Montchadskiana glareolae Dabert and Ehrnsberger, 1999. In this study, we provide morphological diagnoses and illustrations. Additionally, we provide partial sequences of the mitochondrial cytochrome c oxidase subunit I(COI) gene as molecular characteristics of three species.

• 대한영양사협회학술지
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• 제19권3호
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• pp.209-222
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• 2013

This study examined the hygiene practices of contract foodservice employees and investigated the influence of education and work environment on these hygienes practices. A questionnaire was distributed to 250 contract foodservice employees and a total of 232 responses were received and analyzed. The overall score for hygiene practices of contract foodservice employees was 3.89 based on a 5-point scale. Cross-contamination was prominent (highest score at 4.46) and the heating temperature was less prominent (lowest score at 3.49). The factors most affecting contract foodservice employees were their work period, the size of the contract foodservice management company, the number of meals served daily, the frequency of meal service per day and the frequency of hygiene education. Compared to small and medium-sized contract foodservice management companies, the major contract foodservice management companies showed higher scores for refrigerator/freezer control (P<0.001), vegetable/fruit disinfection (P<0.001), thawing (P<0.001), heating temperature (P<0.001), cleaning/disinfection (P<0.01), and personal hygiene (P<0.05). The frequency of hygiene education had a significant effect on the performance levels for refrigerator/freezer control (P<0.001), vegetable/fruit disinfection (P<0.001), thawing (P<0.001), heating temperature (P<0.001), cleaning/disinfection control (P<0.001), food supply control (P<0.05), and personal hygiene (P<0.05). From these results, to increase the sanitation quality of contract foodservice operations, hygiene practice levels need to increase and hygiene education systematically should be enforced for foodservice employees.

• 한국가금학회지
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• 제16권4호
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• pp.233-238
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• 1989

난황과 난백을 냉동저장 할 경우 발생하는 이화학적 변화를 조사함으로써 계란의 효율적인 저장기법을 확립하고자 실시 한 본 실험의 결과를 요약하면 다음과 같다. 1. 난황액을 냉동저장할 경우 Gel화가 발생하였으며 난백액의 경우 포립성과 포립안전성이 감소하였다. 2. 난자액의 동결저장중 Gel화 방지를 위한 각종 동결방지제(소금, 포도당, 설탕, 각종 amide류) 종에서 소금이 가장 효과적이었다. 3. 난황액과 난백액을 $-5^{\circ}C$와 $-20^{\circ}C$에서 냉동저장할 경우 점도가 증가하였으며 색택의 변화가 일어났는데 난백액의 색택변화는 미약하였다. 4. 난황액에 5% NaCl(소금)을 첨가하여 $-5^{\circ}C$에서 저장하는 방법이 난황의 Gel화를 방지하고 경제적으로 저장할 수 있는 방법이었다. 5. 소금을 첨가하여 냉동저장할 경우 난황액의 유화특성은 다소 감소하였다.

• Journal of Advanced Marine Engineering and Technology
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• 제38권7호
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• pp.828-833
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• 2014

본 연구는 이젝터 팽창기를 적용한 냉동기에서 팽창한 냉매가 액기분리기에 포집된 후, 이 중 포화기체의 일부는 이젝터로 재흡입되고, 포화액체는 증발기에 유입되어 증발된 후 액기분리기의 잔여 기체와 혼합되어 압축되는 공정을 고안하여 특성을 해석하였다. 본 공정의 특성은 이젝터에서 등엔트로피 팽창 후 액체량의 증가로 냉동능력이 증가하고, 압축기에 유입되는 기체의 압력이 상승하게 되어 압축일이 감소함으로써 효율이 증가하게 된다. 냉매 R134a를 적용하는 냉장고 시스템과 본 고안 시스템을 비교한 결과, 이젝터에서 압력이 65% 저하될 때 COP는 27.8%가 증가된 최대값이 되었다. 다른 냉매의 경우 R401A가 75% 압력강하에서 40.1%의 COP 증가를 보였다. 이젝터의 디퓨져에서의 압력 상승율이 20%~60%까지 변화될 때, COP 증가율은 2.6%~3%로 영향이 매우 적었다.

• 한국축산식품학회지
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• 제40권3호
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• pp.444-460
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• 2020

This study was conducted to investigate the effects of freezing and storage temperature (-18℃, -50℃, and -60℃) on the physicochemical properties of pork neck and chicken leg meat in home-scale deep freezers. Pork neck was cut into a thickness of 3 cm (9×9×3 cm, 150 g), individually packed in air-containing packages, and stored at different temperature (-18℃, -50℃, and -60℃) for 6 months. Chicken leg meats were prepared (10 cm long, weighing 70 g) and packed in the same manner. Frozen samples were thawed at 2℃. Physicochemical properties such as thawing loss, cooking loss, water-holding capacity, color, volatile basic nitrogen (VBN), and thiobarbituric acid reactive substances (TBARS) were evaluated. The samples frozen by deep freezing (-60℃) was favorable with respect to thawing loss, color, and VBN. Samples frozen at -60℃ had lower values of thawing loss and VBN than those frozen at -18℃ for all storage periods (p<0.05). Color parameters were more similar to those of fresh meat than to those of samples frozen at -18℃ for 6 months. The TBARS of all samples were below 0.3 mg malondialdehyde/kg, thereby indicating oxidative stability of lipids. Consequently, deep freezing at -60℃ may be acceptable for maintaining the quality of fresh pork neck and chicken leg meat for 6 months without deterioration.

• 한국기계가공학회지
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• 제19권1호
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• pp.1-10
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• 2020

This study deals with the fabrication and thermal characterization of planar heating elements attached to the backside of the reflector used in the electrodeless lamp of a freezer. We tried to solve the problem of the local heat generation of the linear heating element that occurs about 50℃. The homogeneous dispersion and manufacturing excellence of the planar heating element produced were confirmed through SEM and EDS. In addition, the test specimens was prepared according to the change in the ratio of carbon fiber to the basis weight of the planar heating element, and a sample having a basis weight of 50g/㎡ having a content ratio of carbon fiber of 70% was selected. That sample showed low surface resistance of 4.3Ω/sq and high temperature of about 81℃ at 6V. Durability was confirmed by performing repeated bending evaluation of 3000 cycles for the sample. Large area test specimens were prepared to be applied to the actual reflector, insulated by EVA film and analyzed for their thermal characteristics. From 13V application, the temperature of the linear heating element was higher than 50℃ and the average temperature of 68℃ was maximum at 18V.

• 대한영양사협회학술지
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• 제30권1호
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• pp.61-73
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• 2024

This report was prepared to introduce the developed Internet of Things (IoT)-based Smart Food Safety Management System (iMEAL) for children's foodservices registered in the Center for Children's Foodservice Management and report the results of hygiene monitoring through microbial analysis of two foods simulated and distributed based on this system. The program consisted of three menu screens: a foodservice management and meal inspection function, a refrigerator/freezer monitoring function, and a sanitary/safety inspection log function. Data such as cooking temperature, refrigerator and freezer temperature, salinity, and chlorine concentration were collected using IoT sensors or terminals, and hygiene safety inspection diary results (recorded by cooks) were transmitted to the Internet and stored. The APCs (3.78±0.07 log CFU/g) and E. coli (not detected) in stir-fried pork teriyaki sauce and the heating process met cooking standards. Similarly, the APCs (4.05±0.05 log CFU/g) and E. coli (not detected) in cucumber/chomuchim, which was not heated, also met cooking standards. APCs increased over time when cooked food was left for 1 hour, 1.5 hours, or 2 hours but remained acceptedable. Based on hygiene monitoring results of these two foods, using the i-MEAL system resulted in the safe production and distribution of children's food.

• 핵의학기술
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• 제15권1호
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• pp.117-120
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• 2011

Glucagon은 췌장 Langerhans섬 ${\alpha}$-세포에서 합성 분비되며, 기능으로는 간 당원분해, 지방분해, 인슐린분비 촉진 작용 등이 있다. Glucagon의 측정은 Glucagon 과잉증에 의한 당뇨병, 특발성 Glucagon 결손증, 불안정 당뇨병에서 저혈당의 진단을 하기위해 실시된다. Glucagon 측정시 세 가지 주의를 요하는데, 첫째, Aprotinin이 첨가된 EDTA tube에 채혈해야 하고 둘째, Plasma를 분리하여 Glass tube에 냉동 보관하여야 하고, 마지막으로 검사시에도 Glass tube에서 측정을 해야 한다. 이에 우리는 EDTA tube에 Aprotinin의 유무에 따른 결과 비교, 검체 보관 용기의 차이에 따른 비교(Plastic tube/ Glass tube), 측정용기에 따른 비교(Plastic tube/Glass tube)를 하여, 세 가지가 결과에 미치는 영향을 알아보고자 한다. 성별 구분 없이 건강검진에서 정상 소견을 보인 성인 40명을 대상으로 실험하여 대조군과 세가지 다른 실험군의 Glucagon 결과를 비교하였다. Aprotinin첨가한 EDTA 용기에 채혈 후, 검체를 Glass tube에 3일 냉동 보관하여 Glass tube에서 실험(대조군)한 결과와 Aprotinin첨가하지 않은 EDTA 용기에 채혈한 결과(실험군1), Plastic tube에 3일 냉동 보관한 후의 결과(실험군2), Plastic tube에서 실험(실험군3)한 결과를 비교하였다. 통계적인 분석은 SPSS를 이용한 paired t-test와 단순선형회귀분석을 실시하였고 시약은 상품화된 Siemens사의 Glucagon RIA kit를 사용하였다. Aprotinin이 첨가된 EDTA 용기에 채혈하여 실험한 결과와 Aprotinin이 첨가되지 않은 EDTA용기에 채혈하여 실험한 상관계수는 r=0.783(p=0.064)를 보였다. 검체 분리 후 Plastic tube에서 3일 냉동 보관하여 실험한 결과는 Glass tube의 결과에 비해서 유의하게 낮게 나타났다(r=0.979, p=0.005). 또 측정 시 Plastic tube를 사용한 결과도 Glass tube에서 실험한 결과보다 유의하게 낮게 나타났다(r=0.754, p<0.001). Glucagon 검사 시에는 단백 분해효소 억제제인 Aprotinin이 첨가된 EDTA tube 사용이 권장되며, Plastic tube 사용 시 환자의 결과가 유의하게 낮게 나타나므로 검체는 분리 후 Glass tube에 냉동 보관하고 Glass tube에서 실험하여야 한다.