• Food Science and Preservation
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• v.14 no.1
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• pp.42-46
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• 2007

To investigate the effects of hot water treatment and modified atmosphere packaging (MAP), compared with non-packaging, of 'Fuji' apples during 18 weeks of storage at $0^{\circ}C$, apple weight loss, firmness, titratable acidity, total ascorbic acid and sensory characteristics were measured After 18 week of storage, the weight loss of MAP-treated apples was 1%, while untreated controls lost 22% of weight Weight loss reduction film packaging was more effective than that afforded by hot water treatment. The firmness reductions in control apples, those receiving hot water treatment those receiving packaging only, and those receiving both hot water treatment and packaging, were 37%, 22%, 10% and 6%, respectively. The titratable acidity was 40% in control apples and respectively, 37%, 32% and 27% in the three groups mentioned above. The total ascorbic acid contentuntreated control apples decreased by 70% after 18 weeks of storage. The total ascorbic acid contentof apples receiving both hot water use of both packagingand hot water treatment to preserve 'Fuji' apple quality.

• Korean Journal of Food Science and Technology
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• v.9 no.3
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• pp.220-224
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• 1977

To dry the sweet potato efficiently, the fresh sweet potato was soaked in hot water of $60{\sim}65^{\circ}C$ for $1{\sim}1.5hrs.$ and cut into 0.5cm thick slices, followed by pressing at $40kg/cm^2$. This predehydrated cake contained $43{\sim}55%$ moisture and can be dried further either by sundrying or hot air drying. Using the dried sweet potato, ethanol was produced (ethanol production; 433l/M/T) by the conventional alcohol fermentation. The extracts as a by-product ($340{\sim}450ml$ per Kg of fresh potato) contained 5% total sugar and may be used directly for alcohol fermentation without further concentration.

• Resources Recycling
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• v.18 no.4
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• pp.52-61
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• 2009

Purpose of this research is deducing optimum pretreatment method of electric arc furnace slag from comparing and investigating the properties of electric arc furnace slag and electric arc furnace slag concrete by existing pretreatment method and surface pretreatment method being used by this research. Besides, as the surface pretreatment method, the method of naturally drying for 6 hours after impregnating with an inorganic type silica solution for 1 day was used. From the results, comparing the hot water treatment method, surface treatment method being used by this research is more effective. Therefore, it is judged that surface treatment method is more effective in the decrease of expansibility of electric arc furnace slag and practical use.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.142.2-142
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• 2003

본 연구에서는 풋고추, 대파와 깻잎에 물리적인 장해를 주지 않고 저장성을 향상시킬 수 있는 열처리 조건을 설정하고, 열처리한 채소의 MAP에 적합한 포장재를 검색하기 위한 실험을 수행하였다. 대파를 55$^{\circ}C$ 온수에서 1분 침지하고, 풋고추와 깻잎은 5$0^{\circ}C$ 온수에서 10초와 5초 각각 침지하면 저장 중 관능적 품질이 비열처리한 대조구보다 우수하게 나타났다. 열처리한 채소의 호흡속도는 비열처리 채소에 비하여 30~45%정도 상승하였다. 열처리 채소의 MAP에 적합한 포장재를 검색하기 위하여 기체 투과도가 서로 다른 포장재 LDPE, CPP, PD900, MPD2055, SM60에 열처리한 채소를 포장한 후 1$0^{\circ}C$에서 4주간 저장을 하였다. 포장 표면에 5mm의 구멍을 뚫은 대조구와 핀홀이 있는 SM60은 저장 2주 이후 부터 중량감소가 심하게 일어났다. 깻잎은 포장내부의 $CO_2$ 농도가 높게 유지되는 CPP에 포장할 때, 저장 2주부터 $CO_2$ 장해로 인하여 표면의 갈변과 연화가 심하게 일어났으며, 풋고추는 저장 3주부터 표면의 색상이 약간 붉은 색을 나타내기 시작하였다. 열처리 풋고추와 깻잎을 MDPE 포장에 저장을 하면 각각 저장 4주와 3주까지는 시장품질의 한계선으로 신선도가 유지되었다. 그러나 대파는 포장 내부의 $CO_2$ 농도가 높은 CPP에 포장할 경우 발근이 억제되며 저장 4주까지 시장품질 이상을 유지하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2016.04a
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• pp.928-930
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• 2016

기존에 흔히 볼 수 있는 수도의 원리상 적절한 온도를 맞추는 데 시간과 어려움이 있다. 온수 방향으로 꼭지를 돌리게 되면 내부온수배관의 물의 양이 많아지고, 냉수 방향으로 돌리게 되면 냉수배관의 물의 양이 많아지게 된다. 이 과정에서 자신이 필요한 적절한 온도를 찾기 위해 꼭지를 좌우로 돌리며 온도를 맞춰야 한다. 이 필요성을 덜기 위해 아두이노를 이용한 수온조절 시스템을 제안한다. 제안하는 시스템은 아두이노의 수온센서와 스텝모터를 이용하여 구현하며 제안하는 시스템을 통해 어린아이를 목욕시키거나 하는 상황에 큰 편리성을 가져다 줄 것이다. 기존에 발표된 시스템과 달리 단순한 기능만을 가지며 저렴한 이 시스템은 향후 일반가정에 좀 더 보급되기 적합하여 많은 사람들이 화상의 위험과, 물의 소비를 줄이는데 도움을 줄 것이다.

• Proceedings of the Korea Information Processing Society Conference
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• 2020.11a
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• pp.269-271
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• 2020

실시간 온도 및 수질 정보를 분석하여 디스플레이에 보여주는 스마트한 수도꼭지로, 수질에 문제가 발생하였거나, 수온이 온수가 안되거나 냉수가 안될 경우 알림이 가는 서비스도 제공하여 문제 해결이 빠르게 가능하다.

• Weed & Turfgrass Science
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• v.7 no.1
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• pp.35-45
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• 2018

The seaweed Ulva spp., which is frequently bloomed in coastal areas, have negatively affected on marine ecosystem and industrial activities. Therefore, many researches have been conducted to solve this problem in the worldwide. In this study, we carried out several experiments to develop the methods for effectively controlling Ulva growth through an alone or mixture application of chemical and temperature. Three chemical mixtures ($H_2O_2$+N-vanillylnonanamide; $H_2O_2$+nonanoic acid; $H_2O_2$+sodium citrate), those had a synergistic effect to the death of Ulva australis (ULAUS), were found out. On the other hand, the death of ULAUS was significantly enhanced and accelerated as some chemicals were briefly treated with warm water of $40^{\circ}C$ rather than $25^{\circ}C$, showing that peracetic acid 100 ppm, sodium percarbonate 100 ppm, and hydrogen peroxide 30 ppm has a better activity than that of sodium chlorite 200 ppm and menadione sodium bisulfite 4 ppm. In addition, a strong synergistic effect to the death of ULAUS thallus was also observed when the sodium citrate 1,000 ppm (pH 3.0) or acetic acid 200 ppm (pH 3.5) solution prepared in f/2 medium were treated in a short time at $40^{\circ}C$. However, an additive effect was only appeared as pH values of their solutions were increased to 8.0. Taken together, It seemed that our results could be developed as one of an eco-friendly practical measures useful for alleviating Ulva bloom in the future.

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.420-428
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• 2019

This study is the heating energy saving test of the high-bed strawberry crown heating system. The system consists of electric hot water boiler, thermal storage tank, circulation pump, crown heating pipe(white low density polyethylene, diameter 16mm) and a temperature control panel. For crown heating, the hot water pipe was installed as close as possible to the crown part after planting the seedlings and the pipe position was fixed with a horticultural fixing pin. In the local heating type, hot water at $20{\sim}23^{\circ}C$ is stored in the themal tank by using an electric hot water boiler, and crown spot is partially heated at the setting temperature of $13{\sim}15^{\circ}C$ by turning on/off the circulation pump using a temperature sensor for controlling the hot water circulation pump which was installed at the very close to crown of strawberry. The treatment of test zone consisted of space heating $4^{\circ}C$ + crown heating(treatment 1), space heating $8^{\circ}C$(control), space heating $6^{\circ}C$ + crown heating(treatment 2). And strawberries were planted in the number of 980 for each treatment. The heating energy consumption was compared between November 8, 2017 and March 30, 2018. Accumulated power consumption is converted to integrated kerosene consumption. The converted kerosene consumption is 1,320L(100%) for space $8^{\circ}C$ heating, 928L(70.3%) for space $4^{\circ}C$ + crown heating, 1,161L($88^{\circ}C$) for space $6^{\circ}C$ + crown heating). It was analyzed that space $4^{\circ}C$ + pipe heating and space $6^{\circ}C$ + crown heating save heating energy of 29.7% and 12% respectively compared to $8^{\circ}C$ space heating(control).

• Journal of the Korean Wood Science and Technology
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• v.35 no.6
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• pp.126-134
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• 2007

This study reviewed the application of an extract from Kalopanax pictus stem bark and root bark as natural antioxidants. To investigate the effect on cell toxic level against transformed mouse fibroblast L929 in formula added with various extracts from Kalopanax pictus stem bark and root bark, this experiment was carried out by in vitro cytotoxicity method. Using DCFA-DA method, oxidative stress in cell was measured with other antioxidant activity methods including DPPH assay and NBT assay. Active oxygen inhibition rate for root bark insoluble hot water extracts showed the highest with 57.9% for 15 min treatment. In DPPH and NBT test, antioxidant activities of methanol extract from stem bark and insoluble hot water extract from stem bark were 96% (at 0.1%) and 95% (at 0.5%), respectively.

• Solar Energy
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• v.15 no.2
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• pp.3-11
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• 1995

This paper reports the performance of solar domestic hot water systems manufactured with heat pipes. A series of tests were conducted on a number of systems to elicit the most suitable configuration of the system for possible commercialization in Korea. The heat pipe is made with a copper tube and the respective length of the evaporator, adiabatic, and condenser sections are 1700mm, 100mm and 200mm. The evaportor section is finned with a copper plate to increase solar input for its proper operation as a heat pipe. Results show quite an interesting performance data stemming from the difference in working fluids, presence of wick, and other various design parameters associated with the collection and utilization of solar energy.