• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.9
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• pp.822-829
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• 2015

In this paper, the piezoelectric-hydraulic pump with a piezostack actuator as a driving source has been designed, fabricated, and evaluated for its application to UAV's brake system. The performance requirements of the piezoelectric-hydraulic pump were decided based on the requirements analysis of the target aircraft brake system. The geometric design of the piezoelectric-hydraulic pump to meet the performance requirements of the pump was conducted, and all components of the pump including the spring sheet type check valves were machined with close tolerance. By constructing a test apparatus for the performance check of the piezoelectric-hydraulic pump, the performance characteristics of the pump, such as the outlet flow rate for load-free condition and the outlet oil pressure for closed loop condition, have been evaluated. It has been found by the performance test result that the developed piezoelectric-hydraulic pump satisfies the design requirements effectively.

• Food Science of Animal Resources
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• v.22 no.1
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• pp.13-19
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• 2002

The natural sources extracted from green tea and pine needle were utilized to investigate the effects of extracts on free radical reaction, lipid oxidation and nitrite scavenging ability. The degree of lipid oxidation is very sensitive to kinds of oil emulsion reacted with iron sources and oxygen species. The antioxidants of extracts from green tea and pine needle were different depending on concentration of extracts, which were a lower TBARS value in 0.3% extracts concentration, compared to 0.1% extracts concentration. And also, the binding ability on iron sources was superior in hot water extracts, but oxygen scavenging ability was the lowest TBARS values in ethanol extracts. The hydroxyl radical scavenging ability of green tea and pine needle extracts had a little low TBARS value in 0.1% and 0.3% extracts concentration in deoxyribose. The ethanol extracts of pine needle were higher than those of hot water extracts on the basis of Fe$\_$2+/ ion content. The ascorbic acid content of green tea showed 14.3 mg/100g in hot water extracts and 16.7 mg/100 g in ethanol extracts. Electron donating ability of extracts showed difference depending on extracts concentration, which were higher in ethanol extracts than those of hot water extracts. The nitrite scavenging effects were tended to be different depending on pH value, however they were decreased overall as pH value was increased. Especially, the nitrite scavenging ability of 0.3% extracts from green tea and pine needle were the mosts effective in pH 1.2 and pH 3.0, which were showed 95% nitrite scavenging ability.

• Journal of Life Science
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• v.23 no.10
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• pp.1273-1279
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• 2013

Aromatic hydrocarbons, such as phenol, have been detected frequently in wastewater, soil, and groundwater because of the extensive use of oil products. Bacterial strains (56 isolates) that degraded phenol were isolated from soil and industrial wastewater contaminated with hydrocarbons. GN13, which showed the best cell growth and phenol degradation, was selected for further analysis. The GN13 isolate was identified as Neisseria sp. based on the results of morphological, physiological, and biochemical taxonomic analyses and designated as Neisseria sp. GN13. The optimum temperature and pH for phenol removal of Neisseria sp. GN13 was $32^{\circ}C$ and 7.0, respectively. The highest cell growth occurred after cultivation for 30 hours in a jar fermentor using optimized medium containing 1,000 mg/l of phenol as the sole carbon source. Phenol was not detected after 27 hours of cultivation. Based on the analysis of catechol dioxygenase, it seemed that catechol was degraded through the meta- and ortho-cleavage pathway. Analysis of the biodegradation of phenol by Neisseria sp. GN13 in artificial wastewater containing phenol showed that the removal rate of phenol was 97% during incubation of 30 hours. The removal rate of total organic carbon (TOC) by Neisseria sp. GN13 and activated sludge was 83% and 78%, respectively. The COD removal rate by Neisseria sp. GN13 from petrochemical wastewater was about 1.3 times higher than that of a control containing only activated sludge.

• Korean Chemical Engineering Research
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• v.46 no.5
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• pp.977-982
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• 2008

The production of ethanol by microbial fermentation as an alternative energy source has been of interest because of increasing oil price. Saccharomyces cerevisiae and Zymomonas mobilis are two of the most widely used ethanol producers. In this study, characteristics of ethanol fermentation by Saccharomyces cerevisiae CHY1077 and Zymomonas mobilis CHZ2501 was compared. Brown rice, naked barley, and cassava were selected as representatives of the starch-based raw materials commercially available for ethanol production. The volumetric ethanol productivities by Saccharomyces cerevisiae from brown rice, naked barley and cassava were $0.68g/l{\cdot}h$, $1.03g/l{\cdot}h$ and $1.28g/l{\cdot}h$ respectively. But for the Zymomonas mobilis, $2.19g/l{\cdot}h$(brown rice), $2.60g/l{\cdot}h$(naked barley) and $3.12g/l{\cdot}h$(cassava) were obtained. Zymomonas mobilis was more efficient strain for ethanol production than S. cerevisiae.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.3
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• pp.247-255
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• 2016

In order to select a strain that forms a Biocellulose (BC), strain producing acetic acid was selected from commercially available kombucha. Through SM broth it was confirmed that the strain is a gram negative bacteria in the form of rods having no motility through a phase contrast microscope. The result of phylogenetic inference analysis based on 16S rDNA sequence analysis for the identification of strains was most closely related to Gluconobacter uchimurae (G. uchimurae) and was named G. uchimurae GYS15 strain. The strain showed the highest degree of growth when cultured for 14 days under the conditions of pH 5 and $25^{\circ}C$. Moreover, it showed the highest degree of growth in a Glucose addition disaccharide as the optimum carbon source sucrose and fructose. Also, 0.5% NaCl, upon the addition of Malto extract, showed the highest degree of growth. Based on investigation by the optimum growth conditions to confirm the physical properties of BC obtained by culturing G. uchimurae GYS15 strains. The surface structure was observed through an scanning electron microscope (SEM) showed a high networks structure. It until $8.6{\pm}0.38$ times when the water holding capacity is re-absorbed and re-absorbed holding oil up to $6.6{\pm}0.51$ times confirmed. In conclusion, using these material properties, it was possible to confirm the possibility of a variety of cosmetic materials and mask pack materials.

• Food Science and Preservation
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• v.9 no.4
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• pp.400-405
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• 2002

Herbs are widely used as a source of tea and otherwise such as botanical medicine, essential oil for perfumes, cosmetics, and food spices. This study was carried out to investigate the characteristics of herb tea prepared with lavender, rosemary, mint, thyme and sage cultivated in korea. Approximate composition were as follows : crude protein 1.4∼17.5%, crude fat 6.1∼15.8%, sugars 43.5∼61s%, crude ash 7.7∼10.7%. Minerals contents of Ca ranged 707∼1763mg%, P 234 ∼513mg%, K 2,391∼3,430mg%, and Mg 361∼573mg%. Vitamins were $\beta$ -Carotene 6.9∼27.7mg%, B$_1$, 0.34∼0.62mg%, B$_2$1.37 ∼2.52mg%, niacin 5.3∼8.8mg%, and C 102∼111mg%. The changes of chromaticity a and b, pH, and sugar content of the herb tea at the different temperatures were decreased 80$\^{C}$ and 100$\^{C}$ in comparison to 60$\^{C}$ but increased chromaticity L. In the result of sensory test of the processed herb tea was more preferred than the market goods.

• Food Science and Preservation
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• v.24 no.6
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• pp.820-826
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• 2017

Soybean is one of the most common food materials for making traditional Korean foods such as soybean paste, soy source and soy snack, and their manufacturing processes include heat treatment of soybean. This study was carried out to investigate the effect of heat treatment on the physicochemical properties of soybean. All samples were heat treated under commercial steamed, puffed or air-fried conditions, and then the protein molecular weight distribution, thermal properties, fluorescence intensity, protein solubility, and water and oil holding ability of the heat treated soybeans were examined. Sodium dodecyl sulfate polyacrylamide gel electrophoresis indicated that heat treatment caused fragmentation of polypeptide chain in soybean, showing the band of low molecular ranging from 17 to 40 kDa. The differential scanning calorimetric analysis showed the decrease of enthalpy values (${\Delta}H$) by heat treatment. Fluorescence spectroscopy indicated that the heat treatment caused lipid oxidation as proved by increasing emission intensity. The protein solubility at pH 3-6, and water holding capacity of heat treated soybeans were the higher than no treatment. These results suggest that the heat treatment resulted in decreased enthalpy values, and increased protein degradation, lipid oxidation and water affinity of soybean. Moreover, the effect of heat treatment on physiochemical properties of soybeans was more significant under air-fried condition.

• Journal of Biosystems Engineering
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• v.41 no.4
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• pp.328-336
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• 2016

Purpose: The heat culture areas of greenhouses have been continuously increasing. In the face of international oil price fluctuations, development of energy saving technologies is becoming essential. To save energy, auxiliary heat source and thermal insulation technologies are being developed, but they lack cost-efficiency. The present study was conducted to save energy by developing a conceptually new semi-basement type greenhouse. Methods: A semi-basement type greenhouse, was designed and constructed in the form of a three quarter greenhouse as a basic structure, which is an advantageous structure to inflow sunlight. To evaluate the performance of the developed greenhouse, a similar structured general greenhouse was installed as a control plot, and heating tests were conducted under the same crop growth conditions. Results: Although shadows appeared during the winter in the semi-basement type greenhouse due to the underground drop, the results of crop growth tests indicated that there were no differences in crop growth and development between the semi-basement type greenhouse and the control greenhouse, indicating that the shadows did not affect the crop up to the height of the crop growing point. The amount of fuel used for heating from January to March was almost the same between the two greenhouses for tests. The heating load coefficients of the experimental greenhouses were calculated as $3.1kcal/m^2{\cdot}^{\circ}C{\cdot}h$ for the semi-basement type greenhouse and $2.9kcal/m^2{\cdot}^{\circ}C{\cdot}h$ for the control greenhouse. Since the value is lower than the double layer PE (polyethylene) film greenhouse value of $3.5kcal/m^2{\cdot}^{\circ}C{\cdot}h$ from a previous study, Tthe semi-basement type greenhouse seemed to have energy saving effects. Conclusions: The semi-basement type greenhouse could be operated with the same fuel consumption as general greenhouses, even though its underground portion resulted in a larger volume, indicating positive effects on energy saving and space utilization. It was identified that the heat losses could be reduced by installing a thermal curtain of multi-layered materials for heat insulation inside the greenhouse for the cultivation of horticultural products by installing thermal curtain of multi-layered materials for heat insulation inside the greenhouse, it was identified that the heat losses could be reduced.

• Journal of Plant Biotechnology
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• v.41 no.1
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• pp.10-18
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• 2014

Seed oils (triacylglycerols) of plants are used as a source of essential fatty acids and nutrition for human. In addition, triacylglycerols have been used as industrial raw materials and biofuels. Triacylglycerols are mainly accumulated in seeds by complicated biochemical pathways. Fatty acids are synthesized in the plastids and transported into the endoplasmic reticulum for synthesizing triacylglycerols. It is known for a long time that biosynthesis of triacylglycerols is performed by a de novo synthesis, the Kennedy pathway. However recent studies have revealed that phosphatidylcholine, a major component of cell membrane, plays a central role for triacylglycerols biosynthesis. Phosphatidylcholine is a key regulator determining the relative proportions of unsaturated fatty acids in seeds. It may be a major carrier for the fluxes of fatty acids from the plastid to the endoplasmic reticulum. This finding further suggests that studies of the functions of enzymes involved in the fluxes of fatty acids from phosphatidylcholine to triacylglycerols elucidate the specialized subdomains in the endoplasmic reticulum for triacylglycerols biosynthesis.

• Korean journal of food and cookery science
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• v.21 no.2 s.86
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• pp.163-170
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• 2005

Soybean is an important plant as the source of protein and oil, as well as phytochemicals such as genistien, daidzein, phenolic acids, phytic acid, tocopherol, and saponin. Chungkukjang, a fermented soybean paste, is common in Korean meals and bacillus is usually used in the fermentation of steamed soybean. For its processing, whole soybeans are boiled in water until the beans are soft, and then the drained beans are wrapped with rice straw or starter and set in a warm place at $65^{\circ}C\;for\;3\;\~\;4\;days$. Normally, the remaining cooked water which was drained from the steamed beans is discarded. We supposed that this water possesses hish amounts of useful components, and we therefore developed a modified method using the cooked water. After fermentation, we added the remaining cooked water which had been drained from the beans to the fermented soy beans and boiled them together. To investigate the bio-functionality of the modified Chungkukjang, the total antioxidative activity, isoflavones contents, phenolic acids, and 3-deoxyglucosone (3-DG) were measured at each stage of the preparation of chungkukjang. The original and modified chungkukjang possessed a high antioxidative activity compared with the other samples, as did the drained water after steaming of the soybean. The contents of genistein, daidzein, and phenolic acids, which contained antioxidative activity, were also increased in the original chungkukjang and their contents were similar in the modified chungkukjang. The content of 3-DG was increased in the modified chungkukjang compare with the original. It is suggested that the active soybean components delivered to the drained water during the steaming process were useful for increasing the bio-functionality of the modified chungkukjang.