• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.1418-1423
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• 2009

This study describes experimental study on the performance characteristics with load condition in hybrid solar heating system during spring season. The room temperatures, the hot water conditions and the lower part temperatures of heat storage tank were changed to analyze the system performances. As a results, the hot water was significantly affected by the ambient temperature. The indoor setting temperature affected the solar fraction. When the low part temperature of the storage tank increased, the temperature of the hot water rose and the temperature of the hot water in morning was affected by the ambient temperature.

• 한국식품영양과학회지
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• 제25권3호
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• pp.484-490
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• 1996

Physicochemical changes were determined for the boiled-dried anchovies packaged in a laminated film(nylon 15${\mu}{\textrm}{m}$/polyethylene 100${\mu}{\textrm}{m}$) and stored for one year at ambient and cooling(5~1$0^{\circ}C$) temperatures after gamma irradiation. Lipophilic and hydrophilic browning pigments increased with storage time particularly at ambient temperature, even though initial 5 kGy irradiation did not affect the formation of pigments significantly. This results were confirmed by the instrumental color determinations, Hunter color L, a, b and ΔE. With respect to changes in relative fatty acid compositions, storage period and temperature were more influential factors than gamma irradiation. Irradiation at 5 kGy induced insignificant changes in the total flavor profiles of stored anchovies, which were mainly composed of n-dodecanal(26.7%), n-pentadecane(22.2%), n-octanal(4.9%) and 2-pentylfuran(3.4%).

• 태양에너지
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• 제20권4호
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• pp.17-24
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• 2000

Thermal performance of a SAAHPS (Solar and Ambient-air-assisted Heat Pump System) located in KIER is simulated with TRNSYS 14.2. The SAAHPS is composed of dual evaorators, each of which is used as a solar fluid heat source and an air fluid heat source. Polynomial coefficients data for the SAAHPS is supplied with Frigosoft, a program widely used for heat pump modeling. In general, collector area and storage volume are 2 key parameters in SAAHPS thermal performance. A parametric study is performed in this study to assess sensitivity of collector area and storage volume in SAAHPS. We concluded that firstly collector area and storage volume are the primary variables in SAAHPS thermal performance, secondly COP of SAAHPS is higher than that of conventional heat pumps. Therefore. collector efficiency can be enhanced swith SAAHPS during a heating season.

• 대한설비공학회지:설비저널
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• 제16권4호
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• pp.392-405
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• 1987

A study of appling solar assisted heat pump heating system to Korean climatic charac-teritics has been undertaken through computer simulation using TRNSYS (A Transient System Simulation Program). It is insufficient for heating system composed of each of solar and heat pump system to supply heat met with heating load. So SAHP (Solar Assisted Heat Pump) heating systems which combined solar system with heat pump system are analized using the standard weather data of Korea. And SAHP heating systems are categorized into the series system in which the solar storage is used as the source for the heat pump, the parallel system in which ambient air is used as the source for the heat pump, and the dual source system in which the storage or ambient is used as the source depending on which source yields the lowest work input. These combined system are better than each of solar and heat pump heating system in view of thermal performance, and parallel system is most effective among these combined systems.

• 태양에너지
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• 제20권3호
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• pp.1-9
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• 2000

In these days the hot water circulating Ondol using the fossil fuel boiler is the heating system for the most of the Korean residents. Then it is installed without the heat storage medium in the Ondol heating layer, but the Korean traditional Ondol had been composed with the heat storage medium. The Ondol room without heat storage medium could not be comfortable because the room air temperature is not only changed unstably but also it has a defect too much fuel consumption. Therefore in this study the heat pump-latent heat storage Ondol as the new type of Ondol system was developed to solve these problems mentioned above, and the COP of the heat pump (Coefficient Of Performance), the latent heat storage characteristics in the new type of Ondol system and the temperature variation in the Ondol room with the ambient temperature were analyzed.

• Journal of Biosystems Engineering
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• 제32권2호
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• pp.102-108
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• 2007

Heat pump systems are recognized to be heating and cooing systems. In this study, to check the practical application possibility of heat pump systems as low temperature storage systems and get basic data, apples of a long term storage items were stored and performance of low temperature storage and quality changes of apples were evaluated. Cooling coefficient of performance of the system was from 1.1 to 1.3. Although ambient air temperature varied widely from $-13^{\circ}C$ to $29.6^{\circ}C$ during low temperature storage period from January to June, the average temperature of low temperature storage chamber was $1.1^{\circ}C$ at setting temperature of $1.5^{\circ}C$. Sucrose of apples stored by the heat pump decreased from initial sucrose of 15.4% (Brix number) to final sucrose of 14.3%. Weight loss ratio of apples was 9.7% and internal and external view of apples after low temperature storage were very satisfactory with the naked eye.

• 원예과학기술지
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• 제32권6호
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• pp.864-871
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• 2014

종자 저장 시 보관조건은 종자의 활력유지에 중요한 영향을 미치며, 급격한 종자활력의 저하는 발아율저하의 중요 요인이 된다. 본 연구의 목적은 주요 채소작물 중 고추(Capsicum annuum L.) 및 배추(Brassica rapa L. ssp. pekinensis) 종자의 저장조건(저장온도 및 보관용기)에 따른 10년 동안의 발아율추이를 조사 분석함으로써 저장기간에 따른 두 종자의 활력유지를 위한 효율적 저장조건을 규명하고자 하였다. 고추 및 배추종자를 각각 진공 알루미늄 호일 봉투, 폴리에틸렌(PET)병 및 종이봉투에 실리카겔과 함께 밀봉하여 상온, $15^{\circ}C$ 및 $5^{\circ}C$ 등 세 가지 온도조건 하에서 10년간 보관하면서 6개월마다 발아율검정을 수행하였다. 고추 및 배추종자는 $15^{\circ}C$ 및 $5^{\circ}C$에서는 보관용기에 상관없이 6.5년까지 저장하기 전의 활력을 그대로 유지하였으나 상온/종이봉투 조건하에서는 각각 4년째 및 5년째에 활력을 잃었다. 상온조건일지라도 진공 알루미늄 봉투에 보관 시 저장 6년까지 보관전의 활력을 유지하였고 특히 고추종자의 경우 저장기간 10년이 경과하여도 90% 이상의 발아율을 나타냈다. 본 연구결과에 의하면 종자저장시설(장기 및 중기)이 없더라도 고추종자의 경우 상온/진공 알루미늄 봉투, 배추종자의 경우 $5^{\circ}C$/진공 알루미늄 호일 봉투에 보관한다면 10년 이상 90% 이상의 발아율을 유지할 수 있을 것으로 사료되며 특히 활력유지 점검을 위한 모니터링 기간을 늦춰 발아검정을 위한 시료낭비를 줄일 수 있을 것으로 판단된다.

• Nuclear Engineering and Technology
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• 제39권2호
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• pp.143-148
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• 2007

Spent nuclear fuel generated at nuclear power plants must be safely stored during interim storage periods. A dry storage cask to safely store the spent nuclear fuel should be able to adequately emit the decay heat from the spent nuclear fuel. Therefore, heat removal tests using a half scale dry storage cask have been performed to estimate the heat transfer characteristics of a dry storage cask under normal, off-normal, and accident conditions. In the normal condition, the heat transfer rate to an ambient atmosphere by convective air through a passive heat removal system reached 83%. Accordingly, the passive heat removal system is designed well and works adequately. In the off-normal condition, the influence of a half blockage in the inlet on the temperature appears minimal. In the accident condition, the temperature rose for 12 hours after the accident, but the temperature rise steadied after 36 hours.

• 한국식품저장유통학회지
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• 제2권2호
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• pp.243-249
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• 1995

Potatoes, Irish cobbler, were subject to quality evaluation from the physiological and physicochemical points of view during storage under different temperatures and relative humidities for 11 months. Quality criteria were sprouting, rotting, weight changes, moisture, total sugar, reducing sugar and vitamin C. Low temperature condition(LT, 2∼4$^{\circ}C$, 80% RH) was enough to preserve Potatoes for 11 months, but it was indicated to be limitations that the increase in reducig sugar as well as sprouting by about 3.3 to 6.7% occurred from the 3rd month of storage. Meanwhile, pit temperature(PT, 3∼15$^{\circ}C$, 75∼85% RH), room temperature(RT, 7∼17$^{\circ}C$, 80∼95% RH) and ambient temperature(AT, 2∼25$^{\circ}C$, 62∼72 RH) were shown infeasible conditions for the storage of potatoes mainly due to the increase In sprouting-rate and subsequent quality-loss after 3 months of storage. Based on the results, it proposed that more economical conditions, ranging 10 to 15$^{\circ}C$ and about 80% RH following sprout inhibition treatment should be used for the long-term storage of potatoes.

• 한국식품저장유통학회지
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• 제6권2호
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• pp.137-142
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• 1999

마늘의 저장조건을 저온(3$\pm$1$^{\circ}C$, 80$\pm$5% RH, LT), 움(9$\pm$6$^{\circ}C$, 80$\pm$5% RH, PT) 및 상온(14$\pm$11$^{\circ}C$, 67$\pm$5% RH, AT)으로 구분하여 9개월간 물리화학적 품질 변화를 조사하였다. 저장 중 마늘의 발아율은 저온조건에서는 상대적으로 낮게 나타났으나 움식 및 상온저장에서는 높게 나타나 이상의 조건에서는 발아억제 방안이 요구되었다. 마늘의 부패율은 저장 7개월 째인 이듬해 3월까지는 낮았으나 그 이후에는 저장조건에 상관없이 급격히 부패되었다. 마늘의 중량은 저장기간이 경과됨에 따라 저장 온ㆍ습도의 변화에 따라 감소하였으며, 특히 외부발아와 더불어 줄어드는 경향이 심하였다. 저온저장에서 수분함량은 이듬해 5월까지 큰 변화가 없었으나 움식 및 상온저장에서는 이듬해 1월부터 상당히 감소되었다. 전당의 함량은 완만하게 감소되는 편이었으나 환원당 함량은 이듬해 3월부터 외부발아 현상과 비례하여 급격히 증가되었다. 마늘의 vitamin C 함량은 저장 중 큰 변화가 없었으나 이듬해 봄부터 발아현상과 더불어 증가되었다. 이상의 결과에서 볼 때 마늘의 저장은 이듬 3월경이 물리화학적 변화가 가장 왕성한 한계 시점이라고 생각되며, 이 한계점을 극복하기 위한 저장조건의 적용이 요구되고 있다.