• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.417-422
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• 2003

The onions are considered to be a favorable functional source of beverage because they contain much sugar and various nutrients, and they are juicy vegetable. Recently, consumers have a new trend to take functional foods with health benefits. To meet this need, this study was the basic research to establish a manufacturing process of functional onion beverage by glucose oxidase. Glucose oxidase catalyzes reaction of glucose oxidation and makes generation of gluconic acid. Kinetics of the reaction was also investigated, and maximum glucose consumption rate $(V_{max})$ of $26.1{\times}10^{-2}\;g/L{\cdot}min$ and $K_m$ of 5.84 g/L were obtained. Optimum conditions were obtained when the glucose oxidase catalyzed reaction was carried out at temperature of $25^{\circ}C$, agitation rate of 450 rpm and aeration rate of 4 vvm in a 2.5 L jar fermentor. Finally, the enzyme reactor was 10-times scaled up and a similar glucose oxidation performance was achieved in the scaled-up reactor.

• Microbiology and Biotechnology Letters
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• v.10 no.2
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• pp.95-100
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• 1982

Torulopsis candida FRI YA-15, a selected yeast, was cultivated in alcohol distiller's waste-filtrate of dried sweet potato for microbial protein production and BOD reduction. The General composition of waste-filterate was BOD$_{5}$ 15700 ppm, COD 36800 ppm, reducing sugar 3300 ppm, total nitrogen 910 ppm, total solids 51800 ppm and ash 390 ppm. The pH of waste was 3.85. The yield to the medium of T. candida cultivated in shake-flask at $25^{\circ}C$ for 48 hrs was 3.38g/$\ell$ and effectiveness in reducing BOD$_{5}$ and COD of waste was 38.9% and 31.8%, respectively. In batch cultivation using 3 $\ell$-jar fermenter, maximum yield to the medium reached 3.2g/$\ell$after 28 hrs cultivation under the condition of temperature 35$^{\circ}C$, initial pH 4.0, aeration rate 2vvm, agitation speed 100rpm. Dry yeast was composed of crude protein 47.98% and ash 5.23%.

• KSBB Journal
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• v.16 no.6
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• pp.632-637
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• 2001

The cells obtained from diesel contaminated site were tested for diesel degradation by culturing them on the culture medium that contained diesel as the only carbon source. Two strains that grew well in the culture media were separated: one formed white colony and another strain formed yellow colony. When they were cultured together, much higher diesel degradation was obtained compares to that of individual cell culture. Mixed culture of white and yellow colony forming strains grew well with 1%(v/v) diesel and the addition of growth nutrients increased the diesel degradation. Additional nitrogen source was efficient for higher diesel degradation (over 90%) when it was compared with that without nitrogen source. When mixed culture of white and yellow colony forming cells were applied to the soil column system contaminated by diesel, 30 mL/min of air flow rate was found to be sufficient to degrade diesel oil. The diesel degradation did not increase noticeably at higher flow rate. The addition of nitrogen source resulted in the increase in diesel degradability.

• KSBB Journal
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• v.10 no.2
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• pp.191-195
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• 1995

Using Pseudomonas sp. CH-414, the optimum culture conditions were investigated for the cell growth and the phospholipid production in batch culture by varying pH and aeration rate. With starting the cultivation under the conditions of pH 7.0 and 1vvm, pH was controlled to 6 or 8 at 30 hours of culture time. In the case of changing into pH 6.0, the phospholipid production was increased by ca. 20% with comparison to the case of pH 7.0. However, the biomass and the phospholipld concentration were rapidly decreased after 30 hours of culture time when pH was controlled to 8.0. As the aeration rate was increased, the biomass was increased while the phospholipid concentration was considerably varied and unstable. Especially, the concentration of phospholipid was rapidly decreased with 3vvm of aeration rate. Finally, under the culture conditions of pH 7.0 and 3vvm until 30 hours for the cell growth, which were controlled to pH 6.0 and 1vvm for the stable production of phospholipid beyond that time, the dry cell weight was $18.5g/\ell$ and the phospholipid concentration was $\0.83g/ell$ (45mg/g cell).

• KSBB Journal
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• v.4 no.2
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• pp.172-176
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• 1989

The alcohol fermentation was carried out to study the effect of aeration and unsaturated fatty acids added on the ethanol tolerance of Saccharomyces cerevisiae STV89 and Kluyveromyces fragilis CBS397. The cell growth rate and ethanol production rate was stimulated by aeration and the cell mass production and ethanol production were also substantially improved. With respect to strains, the maximum specific growth rate and overall ethanol productivity of K. fragilis under aerated condition were 6.4 fold and 4.4 fold higher than those of strictly anaerobic condition, although those of S. cerevisiae were increased 1.7 times and 2.3 times by aeration. The addition of ergosterol, linoleic acid and oleic acid also improved the cell growth and ethanol production of S. cerevisiae and K. fragilis. Thus it was found that oxygen and unsaturated fatty acids added played a decisive role on the increase of ethanol tolerance of yeast strains.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.3
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• pp.299-303
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• 1992

Methods for harvesting and storage of rice were also originally introduced from the ancient China like other practices of agricultural techniques. Thus, optimum time or rice harvesting was adopted by appropriate draining to prevent the losses, and efficient tools were utilized for harvesting and manufacturing. In addition, our unique and original techniques for rice storage were learned and handed down, which prevented winds and rains, and allowed good ventilation. In the 15th and 16th centuries, treatment of smartweed extracts as emphasized to prevent insect damage for stored barley and rice cutting immediately at harvest was encouraged to prevent shattering of rice grains. In the 18th and 19th centuries, means for prevention of damages by water, insects and rats when grains stored in the field were suggested. Also, studies for ecology of various rice cultivars and storage techniques for a long period of time were necessarily emphasized to assume the optimum time of harvest regionally and to cooperatively work timely.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.17 no.1
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• pp.13-17
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• 2011

There is a need in food industry to store minimally processed garlic for long time to have it be used just at the time of demand for final product processing. Optimal modified atmosphere packaging is expected to slow down the quality change extending its storage life. In order to find optimal packaging conditions, plastic films of different gas permeability properties (low density polyethylene (LDPE) $30{\mu}m$, polyolefin $50{\mu}m$ (PD 900), polyolefin $20{\mu}m$ (PD 941)) were used for packaging 400 g of minimally processed garlic. Perforated LDPE packages were prepared as control. The packaged products were stored at $1{\pm}1^{\circ}C$ for 52 days. Package treatments were compared in weight loss, decay, surface color, hardness and soluble solid content. While control package had normal atmosphere of air, LDPE, PD 900 and PD 941 packages attained internal concentration of $O_2$ 4.6% / $CO_2$ 12%, $O_2$ 0.9% / $CO_2$ 21% and $O_2$ 0.5% / $CO_2$ 13% after 45 days, respectively. Control packaging had rapid weight loss with high mold decay and great surface color change in 45 days. In PD 900 film packages of lowest gas permeability, the fresh-cut garlic could be stored without mold decay for 52 days. Except control packaging, there were no significant differences in surface color, hardness and soluble solid content among package treatments.

• Science of Emotion and Sensibility
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• v.21 no.2
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• pp.137-144
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• 2018

The study figured out the operational conditions of a two-way movement actuator made of one-way shape memory alloy (OWSMA) for versatile ventilation intelligent garments. To develop a low-power actuator that consumes energy only when a garment changes its form such as opening and closing, multiple channels of OWSMA were used, and optimum diameter of the wires was examined. For the switch device, optimum voltage application unit time was determined. Optimum diameter of OWSMA wire was determined by applying 3.7V to the pre-determined candidate diameters, which demonstrated two-way operation in previous studies. In order to evaluate the optimum voltage application time, the internal diameter of the actuator was measured while increasing and decreasing by 50 ms from the unit time of voltage application. Delay time under two-way operation of the actuator was measured to minimize interference caused by heat between channels. Power of 3.7V was applied to OWSMA for assessment of optimal time, and the whole process from heating to cooling was video-recorded with a thermal image camera to determine the point of time at which the temperature of OWSMA wire dropped below the phase transformation temperature. The results showed that $0.4{\Phi}$ was the most suitable diameter, and the optimum unit time of voltage applied to open and close the actuator was 4100ms. It was also shown that the delay time should be more than 1.8 seconds between two-way operations of the actuator.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.300-300
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• 2009

화학비료를 이용할 수 없는 유기농업에서의 양분관리를 위해서 녹비, 퇴비, 유박 등을 주 원료로 하는 유기질비료 등 다양한 유기물이 농경지에 투입되고 있다. 그러나 다양한 성분 및 탄소/질소비로 이루어진 유기물은 토양 중에서 분해되는 속도가 다르고, 토양수분함량, 통기성, 온도 등과 같은 토양조건에 따라서도 분해속도가 크게 차이가 난다. 본 실험에서는 유기농업에서 시비원으로 자주 이용하는 퇴비, 유박비료, 녹비조건의 알팔파 등을 이용하여 무기화율 및 양분이용률을 화학비료와 비교하였다. 농경지 투입시 유기물은 질소양분양(21kg N/10a)을 동일하게 투입하였으며 화학비료는 기비(전체량의 1/3)만을 투입하였는데 알팔파, 유박비료의 경우 노지조건에서 토양처리 후 1달 내에 가장 높은 무기화율을 보였으며 수분조건이 제한된 무기화통내에서의 무기화도 2개월 내에 대부분 이루어지는 것으로 나타났다. 수딘그라스를 2개월 재배한 결과 화학비료 질소 양분이용율은 70%, 탄질비가 낮은 유박 및 알팔파는 40%내외, 탄질비가 높고 분해가 어려운 가축분 왕겨퇴비는 10%에 불과했다. 즉 화학비료 대비 유기물 양분(질소)의 비효화 율은 알팔파는 60%, 유박비료는 54%, 퇴비는 14% 였다. 또한 화학비료(100%) 대비 인산 이용률(유박: 296%, 알팔파: 660%, 퇴비: 36%로, 인산의 이용율이 높은 것은 유기물로 투입된 인산의 량이 화학비료보다 낮아 상대적으로 유기물질에 의한 작물의 인산이용율이 높고, 화학비료는 토양중 고정화가 작물생육 초기에 일어나는데 비하여 유기물질은 서서히 분해되면서 작물에 흡수되어 인산이용율이 높은 것으로 추정된다. 수단그라스 1차수확 후 포장침수로 인한 생육불량으로 전 생육 과정을 통한 양분흡수율은 측정할 수 없었다.

• Journal of the Korean Solar Energy Society
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• v.26 no.1
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• pp.81-89
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• 2006

Building integrated photovoltaic (BIPV) system operates as a multi-functional building construction material. They not only produce electricity, but also are building integral components such as facade, roof, window and shading device. On the other hands lots of architectural considerations should be reflected such as Installation position, shading, temperature effect and so on. As PV modules function like building envelope in BIPV, combined thermal and PV performance should be simultaneously evaluated This study is on the combined thermal and PV performance evaluation of BIPV modules. The purpose of this study is to investigate a temperature effect of PV module depending on the ventilation type of PV module backside. Test cell experiment was performed to identify the thermal and power effect of PV modules. Measurement results on the correlation of temperature and power generation were obtained. Those results can be utilized for the development of optimal BIPV installation details in the very early design stage.