• Resources Recycling
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• v.24 no.4
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• pp.56-60
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• 2015

Fine particle classification was performed using products obtained from primary classification process after flotation for efficient application of tailing. The cut size increased with decreasing input pressure from 0.1 MPa to 0.3 MPa and increasing pulp density from 5% to 15% using 2-inch hydrocyclone. The median sizes of overflow and underflow were $6.56{\mu}m$ and $55.45{\mu}m$, respectively at 0.3 MPa with 5% pulp density. The imperfection became closed to ideal separation with increasing the pulp density and decreasing the input pressure. The water content decreased with increasing the pulp density, but the effect of input pressure could be ignored. The water content of underflow was 27.9% at 0.3 MPa with 15% pulp density.

• KSBB Journal
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• v.19 no.2
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• pp.148-153
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• 2004

Lipase catalyzes the hydrolysis of glycerides into fatty acids and glycerol. The study of microbial lipases has been stimulated in resent years. It is due to the potential uses of lipases in esterification of oils to glycerol, alcohols and carbohydrates. Development of lipase producing yeast has been focused concerning to the utilization of yeast culture for animal feed. In this study, yeast like cells was isolated from a waste oil and sludge. A strain having higher lipase activity was selected by random mutagenesis using UV-radiation. The optimal cultivation conditions in submerged culture were examined in terms of lipase production. 2.0％ of high fructose syrup, 1,0％ of CSL, and 1.0％ of olive oil were selected as the nutritional media for the production of lipase. The maximum lipase activity of 1.12 U/ml and viable cell number of 8.8${\times}$10$\^$7/ cells/mL were obtained at 27$^{\circ}C$ with an initial pH of 5.0.

• KSBB Journal
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• v.19 no.6 s.89
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• pp.478-483
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• 2004

The optimum fermentation conditions of Propionibacterium acidipropionici were determined for the maximum production of organic acids. Three strains of P. acidipropionici, ATCC 25562, 4875, 4965 were selected to test the productivity of organic acids in the batch fermentation. Nutrients and environmental conditions on cell growth were defined by series of experiments, and the optimum amounts of peptone, yeast extract were determined to be $1.5\%$ (w/v), $0.75\%$ (w/v), respectively. The yields and productivity were highest at pH 6 among the ranges of $5.0{\sim}7.5$, and ATCC 4965 was determined to be the best strain compared to the others by getting total productivity of 0.29 g total acids/L/h. Approximately $1.60{\sim}2.34$ moles of propionic acid and $0.74{\sim}1.05$ moles of acetic acid were produced from 1.5 moles of glucose.

• Resources Recycling
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• v.11 no.3
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• pp.10-16
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• 2002

In the leaching of $LiCoO_2$with a strong acid such as sulfuric and nitric acid, an additional step was needed to recover cobalt and lithium separately from spent lithium ion batteries (LIBs). The leaching of $LiCoO_2$in an oxalic acid solution was investigated to recover cobalt selectively using a low solubility of cobalt oxalate at low pH. Leaching efficiency of 95% of lithium and less than 1% of cobalt were obtained when pure $LiCoO_2$powder was leached in 3M oxalic acid at $80^{\circ}C$ and 50 g/L pulpdensity. Under the above leaching conditions, complete dissolution of lithium was accomplished with mere 0.25% of cobalt in the solution when the cathodic active material collected from spent LIBs was employed. The lithium in the leaching solution can be recovered as a form of carbonate or hydroxide depending on the addition of $Na_2$$CO_3$or LiOH.

• Resources Recycling
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• v.28 no.5
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• pp.19-29
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• 2019

Recently, it is increasing a amount of installized solar-cell rapidly, and waste Solar cell module are generated in according to the reduction of efficiency largely. Therefore, it is concerned at the environmental problems and recycling of valuable materials, greatly. The treatment processes of end-of-life photovoltaic modules are composed the disassembly of Aluminum frames, separation of Tempered glass, removal of Ethylene Vinyl Acetate and recovery of valuable Metals. For the efficient recycling, we are considered to the treatment technology seriously. And we are proposed on the general opinions according to the developing technology, EPR (Extended Producer Responsibility) problems and promotion plans for the activation of recycling industry.

• The Korean Journal of Archival Studies
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• no.27
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• pp.89-118
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• 2011

This paper considers the relationship between memory and archives by exploring the concepts and meaning of archivist and archival description. The author considers the metaphor of archives as memory and relates our understanding of creation, arrangement, preservation, description, and use of records and archives. The author argues that archivists demonstrate their knowledge and background when they organizing and preserving records and archives.

• Journal of Korea Society of Industrial Information Systems
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• v.14 no.4
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• pp.116-127
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• 2009

This research aims to improve the efficiency of production by selecting production configuration with high yield rate and lower error rate based on production history of steel pipe. To achieve this, we identify the properties of various types of MTO(make-to-order) steel pipe products and determine properties affecting yield rate and error rate using decision tree technique. From experimental results, we find out that specification is critical to determine yield rate and error rate of ERW steel pipes with mostly small and medium caliber, and an external diameter range in case of roll benders or spiral steel pipes with mostly large caliber. This research classified and embodied the patterns of yield rate and error rate mathematically by product properties.

• KSBB Journal
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• v.15 no.2
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• pp.125-133
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• 2000

Specific carotenoids and astaxanthin biosynthesis power of Phaffia rhodozyma mutant 876, which was obtained after NTG a and UV treatments, was higher than those of the wild type by 40% and 50%, respectively. The mutant strain did not show t the catabolite repression even at 22% (w/v) glucose concentration. The optimum C{N ratio was 2.0, and the optimum t temperature and initial pH were $22^{\circ}C$ and 6.0, respectively. 80th cell growth and astaxanthin formation decreased drastically a as the fermentation temperature was increased over $22^{\circ}C$, whereas they were comparable in the pH range between 5.0 and 7 7.0. Inoculum size did not affect the final cell density nor the carotenoids biosynthesis, and 3%(v/v) was selected as optimal. H Higher dissolved oxygen concentration facilitated astaxanthin biosynthesis, and aeration rate of 1.0 v/0/m and agitation speed of 400 rpm were selected as optimum. The final cell dens때 of 43.3 g/L and the volumetric astaxanthin and carotenoids concentrations of 110.6 mg/L and 149.4 mg/L, respectively, were obtained. The specific carotenoids concentration was 3.45 m mg{g-yeast(dry). Yx/s and Yp/s values of 0.37 and 1.08 were obtained. The result of this study will provide basic information u useful for mass production of astaxanthin from P. rhodozyma fermentation.

• Food Science and Preservation
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• v.23 no.5
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• pp.746-752
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• 2016

This research was carried out to identify aerodynamic property as a function of moisture content for designing equipment such as for post-harvest management. Terminal velocity of two wheat varieties {Backjjung (B) and Jogyeong (J)} with selected sound, damaged kernel and foreign materials (Wheat stick, Wheat husks) were measured with a designed vertical wind column at different moisture contents from about 9 to 30% wet basis. The results showed that terminal velocity of wheat and foreign materials except of Jogyeong's husks (p<0.05) had a significant difference at p<0.001. With increasing moisture content, the aerodynamic property values of the kernels and foreign materials of the two wheat varieties increased linearly. In detail, terminal velocity of sound and damaged kernel increased from 5.46 to 7.13 m/sec (B) and 7.48 to 8.60 m/sec (J), damaged kernel from 5.91 to 7.00 m/sec (B) and 6.48 to 7.75 m/sec (J). For foreign materials the terminal velocity of wheat stick increased from 2.92 to 4.07 m/sec (B) and 3.74 to 5.22 m/sec (J) whereas that of husks from 1.07 to 1.85 m/sec (B) and 2.02 to 2.33 m/sec (J) each. For air separation of wheat and foreign materials, the air flow should be less than 5.22 m/sec due to the range (1.07~5.22 m/sec) of foreign materials in wheat.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.4
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• pp.592-601
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• 2015

Rubus coreanus is known as Korean black raspberry, native to Korea, Japan, and China. Preliminary studies evaluating their potential for cancer treatment in mammalian test systems are ongoing. In recent years, interest has been renewed due to their high levels of anthocyanins. Anthocyanins in black raspberry are important due to their potential health benefits as dietary antioxidant, anti-inflammatory compound, and as a chemopreventive agent. In the present study, Saccharomyces cerevisiae BA29 was isolated from black raspberry fruit and fruit juice as a biogenic amine non-producing strain for manufacturing of black raspberry wine, after which we investigated its characteristics: biogenic amine-producing ability, cell growth ability, alcohol-fermentation ability, and resistance to alcohol, glucose, and sulfur dioxide. Based on preliminary experiments, we optimized culture medium compositions for improving dried cell weight of S. cerevisiae BA29 by response surface methodology (RSM) as a statistical method. Design for RSM used a central composite design, and molasses with the industrial applicability was used as a carbon source. Through statistical analysis, we obtained optimum values as follows: molasses 200 g/L, peptone 30 g/L, and yeast extract 40 g/L. For the model verification, we confirmed about 3-fold improvement of dried cell weight from 6.39 to 20.9167 g/L compared to basal yeast peptone dextrose medium. Finally, we manufactured black raspberry wine using S. cerevisiae BA29 and produced alcohol of 20.33%. In conclusion, S. cerevisiae isolated from black raspberry fruit and juices has a great potential in the fermentation of black raspberry wine.