• 설비공학논문집
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• 제10권3호
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• pp.343-347
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• 1998

The objective of this study is to manufacture the low temperature waterless container that is compact and low cost for a live fish transportation. Using the low temperature water container, it makes observations on the optimal conditions such as the amount of dissolved oxygen, total ammonia and nitrite in seawater for determining the survival rate of live fish in short and long-term transportation. Using a sole as a live fish, the temperatures of $0^{\circ}C$, 3$^{\circ}C$, 5$^{\circ}C$, 7$^{\circ}C$, 15$^{\circ}C$ were controled for there effects. The results of this investigation show that as the seawater temperature increased, the amount of oxygen decreased and there was a low temperature shock below 3$^{\circ}C$. It was observed that the fish was died with 30$m\ell/\ell$of ammonia. The optimal temperature is about 5$^{\circ}C$ for live fish transportation to maintain best survival rate.

• 설비공학논문집
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• 제12권5호
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• pp.519-524
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• 2000

The purpose of this study is to develop a low temperature waterless container for live fish transportation which is economical and efficient The principle of the waterless transportation is that a live fish becomes asphyxial at about $5^{\circ}C$can survive without water for a long time. A low temperature waterless container is developed for this purpose, which utilizes thermoelectric modules for rather smaller and lighter cooling system with precise temperature control devise compared to the existing mechanical system. At first, we succeeded in making flounders alive in the waterless container for 24 hours. Also when flounders were transported in a round trip from Inchon to Pusan in the waterless container, carried in a car, they survived in the waterless container for over 21 hours.

• 한국정보통신학회논문지
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• 제21권12호
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• pp.2380-2386
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• 2017

국내에서 생산되는 신선농산물은 현재 정부의 보조금 지원을 받으며 비싼 항공운송을 이용하여 해외로 수출되고 있다. 하지만 2023년부터 정부의 보조금 지급이 중단됨에 따라 저렴한 비용으로 많은 화물 운송이 가능한 해상운송을 이용할 필요가 있다. 신선농산물의 해상운송에는 냉동컨테이너가 사용되는데 현재 냉동컨테이너는 화물 적재부 내부 온도편차가 크게 발생하여 운송 중 신선화물의 부패 등에 따른 문제가 있다. 이를 해결하기 위해 본 연구에서는 냉동컨테이너 내부 온도를 일정하게 유지하며, 편차를 최소화 할 수 있는 냉동컨테이너 온도 제어 알고리즘을 개발하였다. 개발한 알고리즘을 참외 싱가포르 해상운송 경로에 적용하여 그 기능을 검증하였다. 검증 결과 설정온도 $4.0^{\circ}C$를 기준으로 최대 $0.5^{\circ}C$이내에서 화물 적재함 내부 온도가 유지되는 것을 확인 할 수 있었다.

• 한국기계가공학회지
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• 제21권2호
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• pp.94-100
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• 2022

A study was conducted to significantly increase the heat transfer area by simultaneously burying the excel pipe in the floor and wall of a container house, thereby greatly reducing the initial heating time. In addition, a small hot water boiler suitable for the heating load of a small container house with a maximum area of 6 m² was studied. A wall-mounted hot water boiler was developed as a result of the study. When a hot water boiler is installed outdoors for heating, heat radiation energy is lost in winter from the hot water boiler and hot water pipe due to the low temperature. We propose an approach through which the energy loss was greatly reduced and the temperature of hot water increased in proportion to the operating time. Moreover, as the mass flow rate of the hot water flowing inside the excel pipe increased, the temperature of the hot water decreased. The temperature of the wall and floor surfaces of the container house increased in proportion to the increase in the mass flow rate of hot water flowing inside the excel tube. Natural convection heat transfer was realized from the wall and floor surfaces of the container house, and the heat transfer area was increased by a factor of 3 with respect to heat transfer area limited to the floor by the existing hot water panel. As a result, the initial temperature increase rate was much higher because of the larger heat transfer area.

• 한국포장학회지
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• 제29권3호
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• pp.195-201
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• 2023

Garlic (Allium sativum)is a major crop in most Asian countries, and its consumption in Asia-Pacific countries exceeds 90% of the global consumption. It contains beneficial ingredients and numerous essential nutrients, such as manganese, vitamin B6, and vitamin B1. Garlic demand is rising not only in Asian countries but also around the world. Particularly, garlic demand has been steadily increasing in European countries, such as Spain, France, Italy, and the American continent. In South Korea, 331,671 tons and 387,671 tons of garlic was produced in 2018 and 2019, respectively, making the country the fifth ranking garlic producer in the world, and the production has been increasing every year. In this study, the study on temperature distribution in cold storage of Korean garlic in folding wire mesh pallet container using CFD (Computational Fluid Dynamics) analysis was performed and Computations were based a commercial simulation software (ANSYS Workbenh Ver. 18.0). Considering the respiration heat of garlic, the decreasing rate of temperature in the area in contact with the cold air was fast due to the inflow of cold air inside, while the decreasing rate of temperature in the center of the pallet was very low. In order to maintain a uniform temperature distribution inside the agricultural product storage pallet in a low-temperature warehouse, it is considered desirable to install an air passageway to allow low-temperature air to flow into the wire mesh pallet.

• International Journal of Internet, Broadcasting and Communication
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• 제14권2호
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• pp.79-88
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• 2022

Recently, securing stable supply of fresh food is deemed as one of the important tasks. Accordingly, now the presence of cold chain along with the needs of a comfortable and healthy life is growing as the online market expands and the contactless industry grows, however, cold chain is being studied only in the aspect of ground and sea transportation. And, due to global warming and strengthening global environmental regulations, we believe that it is necessary to convert the existing road-centered logistics system into a railway-centered logistics system, a low-carbon transportation means. Therefore, in this paper we calculated the maximum energy required by the reefer container as a basic research necessary for constructing the low temperature distribution and cold chain based on the reefer container railway, and conducted a study on methods of supplying the reefer container power utilizing 1. tramline, 2. battery, 3. generator. The results of this paper can be utilized as a foundational study for building a cold chain based on a reefer container dedicated to freight trains in the future.

• Journal of Ginseng Research
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• 제29권2호
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• pp.113-118
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• 2005

본 연구는 수삼의 저장용기로 많이 이용되고 있는 플라스틱 상자의 통기구 비율 즉 개공율이 수삼의 저장성에 미치는 영향을 조사하기 위하여 개공율을 밀폐(0), 1, 3, 5, 및 $10\%$로 설정하여 실온에서$(19\~23^{\circ}C,\;RH\;40\~61\%)$ 10일간, 냉장으로$(4\~9^{\circ}C,\;RH\;72\~92\%)$ 30일간 저장하면서 이 화학적 변화를 조사한 결과는 다음과 같다. 실온에서 외관변화는 밀폐구에서 4일 부터 곰팡이 발생이 관찰되며 10일째는 부패하였고, $1\%$는 8일부터 곰팡이 발생이 관찰되었다. $5\%$와 $10\%$ 개공율은 4일부터 시들기 시작하였다. 중량감모율은 개공율이 높을수록 많이 나타나 $5\%$와 $10\%$개공율에서 4일후 $10\%$이상 나타났다. 유리당은저장기간의 경과에 따라 maltose와 sucrose가 감소하였는데 개공율이 낮을 수록 많이 감소하였다. 냉장에서 곰팡이 발생은 관찰되지 않았으며 중량모율은 $5\%$와 $10\%$ 개공율에서 12일부터 약 $10\%$를 보이면서 시들기 시작하였으며, 밀폐와 $1\%$는 30일간 저장기간에서도 양호한 외관상태를 보였다. 유리당중 maltose는 감소, sucrose는 감소하였다가 증가하는 경향을 보였다. 이상의 결과에서 보관상자의 개공율을 조절하여 수삼의 저장성을 향상시킬 수 있음을 알 수 있었다.

• 한국포장학회지
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• 제28권3호
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• pp.217-221
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• 2022

저온에서 신선육을 보관 저장하는 용기의 기체조성을 고CO₂/저O₂ 농도로 자동적으로 제어하는 용기 시스템을 제작하고, 0℃에서 21일간 돼지고기 삼겹살을 담아 저장하면서 품질보전의 측면에서 진공 포장과 함기 대조구 조건과 비교하였다. CO₂ 주입 시간 프로그램에 의하여 CO₂ 농도는 47~60%, O₂ 농도는 7~10%로 유지될 수 있었고, 이는 호기적 세균 증식과 pH 증가의 억제의 효과와 함께 관능적 품질유지에 기여하였다. 진공포장은 함기 대조구에 비하여 낮은 미생물 성장과 pH 증가를 보여주었으나 높은 drip 손실의 단점을 보였다. 전체적 품질보존의 측면에서 고안된 고CO₂ 치환 용기는 육류의 품질유지에 효과적이며, 육류의 종류와 특성에 맞게 기체 농도 조건을 변경하여 활용범위를 확장할 수 있을 것이다.

• 한국가시화정보학회지
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• 제22권1호
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• pp.6-17
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• 2024

This study examined the natural convection heat flow characteristics of the melting process of PCM (palm oil) inside a liquid flexitank(bag) for a cargo container. A film heating element was installed on the bottom of the container, and numerical analysis was performed under heat flux conditions of 1,000 to 4,000 W/m². As a result, the melt interface of the PCM rises to a nearly horizontal state over time. In the initial stage, conduction heat transfer dominates, but gradually waves at the cell flow and melt interfaces are formed due to natural convection heat transfer. As melting progresses, the Ra number increases parabolically, and the Nu number increases linearly and has a constant value. The Nu number rises slowly under low heat flux conditions, whereas under high heat flux conditions, the Nu number rises rapidly. As the heat flux increases, the internal temperature oscillation of the liquid phase after melting increases. However, under high heat flux conditions, excess heat exceeding the latent heat is generated, and the temperature of the molten liquid is raised, so the increase in melting rate decreases. Therefore, the appropriate heating element specification applied to a 20-ton palm oil container is 2,000 W/m².

• 한국조경학회지
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• 제29권1호
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• pp.152-160
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• 2001

This study is conducted to evaluate the effects of containerized landscape tree production methods on post-transplant stress. Two types of container such as plastic pot(pot), fabric growing bag(bag) were adopted to restrict tree roots. Each types of containers was divided into seven sub-types. One traditional production method was included as comparison. Two landscape woody plants species (Magnolia denudata, Albizzia julibrissin) were implanted in the 7 sub-types of container. After one or two growing season in the container, each types of container trees was transplanted. Half of the trees were transplanted in the mild spring season, and another half of trees were transplanted in the improper summer season. The data were collected on the crown wilting ratio and trunk die-back ratio. The result of the analysis based on these data were as follows; 1) The container production methods were lower than the traditional production methods by 3 times in the average wilting ratio of summer season's transplanting point. 2) Post-transplant stress was more successfully mitigated, in case the "pot" type as was the "bag" types of container. 3) The effective and economic way of mitigating post-transplant stress by container production methods was selecting container plants of vigorous and deep root systems. 4) The "pot" type of container was to restrict tree roots more successfully, But, winter chilling and low temperature attacked the "pot" type tree's twigs and suckers. These results indicated that "pot" grown container plants should managed carefully during the winter after transplanting. Based upon the results of this study, a subsequent research on the development of container material, growth type of the container trees, and other maintaining method will be required.es, and other maintaining method will be required.