• ALGAE
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• v.31 no.1
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• pp.61-72
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• 2016

Arctic microalgae thrive and support primary production in extremely cold environment. Three Arctic green microalgal strains collected from freshwater near Dasan Station in Ny-Alesund, Svalbard, Arctic, were analyzed to evaluate the optimal growth conditions and contents of fatty acids. The optimal growth temperature for KNF0022, KNF0024, and KNF0032 was between 4 and 8℃. Among the three microalgal strains, KNF0032 showed the maximal cell number of 1.6 × 107 cells mL^-1 at 4℃. The contents of fatty acids in microalgae biomass of KNF0022, KNF0024, and KNF0032 cultured for 75 days were 37.34, 73.25, and 144.35 mg g^-1 dry cell weight, respectively. The common fatty acid methyl esters (FAMEs) analyzed from Arctic green microalgae consisted of palmitic acid methyl ester (C16:0), 5,8,11-heptadecatrienoic acid methyl ester (C17:3), oleic acid methyl ester (C18:1), linoleic acid methyl ester (C18:2), and α-linolenic acid methyl ester (C18:3). KNF0022 had high levels of heptadecanoic acid methyl ester (26.58%) and heptadecatrienoic acid methyl ester (22.17% of the total FAMEs). In KNF0024 and KNF0032, more than 72.09% of the total FAMEs consisted of mono- and polyunsaturated fatty acids. Oleic acid methyl ester from KNF0032 was detected at a high level of 20.13% of the FAMEs. Arctic freshwater microalgae are able to increase the levels of polyunsaturated fatty acids under a wide range of growth temperatures and can also be used to produce valuable industrial materials.

• Journal of Digital Convergence
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• v.12 no.2
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• pp.173-182
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• 2014

The government aims at promoting the national growth and heightening efficiency through the creativity economy. This study focus on the effectiveness(difference of the tax bearance) of tax-aid system(tax-reduction and tax-deduction) for the venture firms and small & medium firms. Sampling of this study was collected through what had been recorded to the enterprise information service of Korcham(venture firms), DB of Small & Medium Business Administration Authority from 2010 to 2012, and opened information of the KOSDAQ Association. The results were as follows. Firstly, There exists differences in the tax bearance rate between the tax-aided corporation and the tax-nonaided corporation through venture firms and small & medium firms. Secondly, Venture firms were investigated to bear low tax-bearance rate in contrast to Small & Medium Firms. The results of this study shows that the national tax-aided system is effective, and can be led to another new politics alternatives.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.293-293
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• 2017

The objective of this study was to determine physicochemical changes in brown rice during ageing condition. Five varieties (Haiami, Ilpum, Daecheong, Jungwon, and Dasan1) of brown rice were stored at $35^{\circ}C$ for 8 weeks. Crude protein and lipid content, seed germination rate, fat acidity, tocol content, TOYO glossiness value, pasting properties, and composition of storage proteins were measured to evaluate its quality during storage. The isomers of tocols (tocopherol and tocotrienols) were quantified using HPLC system, and the pattern of variation in rice storage proteins was examined through electrophoresis of protein extracts. Seed germination rate decreased by 2.7 times, whereas the fatty acid value dramatically increased by 4.8 times after 8 weeks of storage. Toyo glossiness value of cooked milled rice considerably affected by storage period, and the pasting properties of milled rice were also influenced by storage. The final viscosity and breakdown value increased, but setback decreased during storage. In terms of storage protein, proportion of prolamin (14.3 kDa) and globulin (26.4 kDa) increased, whereas percentage of glutelin (34-39 kDa and 21-22 kD) decreased. Furthermore, the contents of total tocol and isomers decreased in stored brown rice.

• Food Science of Animal Resources
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• v.37 no.6
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• pp.926-930
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• 2017

High-quality meat is of great economic importance to the pig industry. The 1-acylglycerol-3-phosphate-O-acyltransferase 5 (AGPAT5) enzyme converts lysophosphatidic acid to phosphatidic acid in the mitochondrial membrane. In this study, we found that the porcine AGPAT5 gene was highly expressed in muscle tissue, influencing meat characteristics, and we also identified a non-synonymous single-nucleotide polymorphism (nsSNP) (rs196952262, c.673 A>G) in the gene, associated with a change of isoleucine 225 to valine. The presence of this nsSNP was significantly associated with meat color (lightness), lower cooking loss, and lower carcass temperatures 1, 4, and 12 h after slaughter (items T1, T4, and T12 on the recognized quality scale, respectively), and tended to increase backfat thickness and the water-holding capacity. These results suggest that nsSNP (c.673A>G) of the AGPAT5 gene is a potential genetic marker of high meat quality in pigs.

• Journal of the Korean Geotechnical Society
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• v.27 no.3
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• pp.19-26
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• 2011

Compaction tests have been performed to investigate the compaction characteristics of sands and clays with organic mixture. Weathered granite soil, kaolinite, and granulated carbon were used as the alternatives of sand, clay, and organics, respectively. The soapy water which is a kind of surfactant solutions was also used as water substitute to see the engineering properties changes of each soil. As seen when water was used, the optimum moisture contents increased and the maximum dry unit weight decreased for the soil with surfactants as the percentage of the organic contents increased. Surfactants slightly improved the compaction efficiency at low compactive energy level for the weathered granite soil with organics. As the organic contents increased for clays with surfactants, the optimum moisture contents decreased and the maximum dry unit weight increased. Surfactants slightly improved the compaction efficiency of clays with organics at all levels of compaction energy.

• Journal of the Korean Geotechnical Society
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• v.28 no.10
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• pp.17-25
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• 2012

Shotcrete, rockbolt, and steel rib are installed to support ground after tunnel was excavated. These are important supports for NATM applied tunnels. Recently, lattice girder is increasingly used because it is easily installed. In this study, we developed a new lattice girder by increasing contacting area between spider and rod. To verify the effect of the new lattice girder, the 3-point and 4-point flexural strength tests were carried out for LG-$50{\times}20{\times}30$, LG-$70{\times}20{\times}30$, LG-$95{\times}22{\times}32$. As a result, in case of contacting area, strength of new SGS lattice girder is 17.95% higher than that of original lattice girder. In case of weakness point, strength of new SGS lattice girder is 19.37% higher than that of original lattice girder.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.5
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• pp.869-886
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• 2018

Rockbolt is one of the most common supports used to reinforce discontinuous rock during underground excavation. Extra drain pipes are installed to improve excavation workability and the anchorage of rockbolts in water bearing ground. The drain pipe is effective in improving the workability by providing drainage path, but it is difficult to expect the reinforcement effect, increasing disturbance of the discontinuous rock mass and the construction cost. To solve this problem, dual purpose rockbolt (DPR) has been developed for the reinforcement of rock and the drainage of ground water. DPR was able to improve the mechanical and hydraulic stability of the rocks quickly and economically. Two kinds of DPRs using FRP (Fiber Reinforced Plastic) and steel were investigated for the mechanical and hydraulic performance. Also, the workability and stability of DPR were analyzed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.1
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• pp.59-63
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• 1999

Yield and growth characteristics were compared for five rice cultivars; a new Tongil-type, so called "super-rice", Dasanbyeo, an old Tongil-type Milyang 23, two japonicas Dongjinbyeo and Ilpumbyeo, and a new plant type (NPT)line IR65600-27-1-2. The objective of this stusy was to clarify the high yielding capacity of Dasanbyeo in terms of growth characteristics. The average grain yield (9 t/ha) of Dasanbyeo was higher than that of Milyang 23 by ca. 9% that of japonicas by 20 to 30%, and that of NPT line by ca. 100%. The higher grain yield of Dasanbyeo was attributable not only to the greater dry matter production but also to the higher harvest index (HI). Dasanbyeo showed the greatest dry matter at harvest owing not only to the rapid leaf expan-sion at early growth stage and the resulting high LAI through the entire growth stage but also to the high NAR despite the high LAI. The rapid leaf expansion of Dasanbyeo at early growth stage seemed to be related in part to the profuse tillering capacity. HI was 0.53 in Dasanbyeo, 0,51 in Milyang 23, 0.41 in japonicas, and 0.35 in NPT line. Dasanbyeo was indebted for its higher HI to the relatively high grain filling ratio in spite of a much greater sink size than the other cultivars. Dasan had a greater source to sink ratio during grain ripening as measured by LAD/spikelet and dry matter production/spikelet which showed positove correlations with the grain ripening ratio. New plant type (NPT) line showed the lowest grain yield owing to the small sink size and the low grain filling ratio which seemed to have resulted from the abundant occurrence of weak-strength spikelets. The weak sink strength, in turn, seemed to have suppressed photosynthesis during the grain ripening stage.

• Journal of the Korean Geotechnical Society
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• v.28 no.8
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• pp.79-88
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• 2012

In this study, the tunnel loads acting on the concrete lining are analyzed by comparing three methods - Terzaghi table, Terzaghi formula and Ground-Lining Interaction (G.L.I) model. The tunnel loads are analyzed by FLAC 2D. And the G.L.I model is analyzed under various rock mass ratings, tunnel depths (20~80m) and in-situ stress ratios ($K_0$=0.5~2.0). Terzaghi's method can be applied only to weathered rocks and soils, and cannot reflect the effect of various tunnel depths and in-situ stress ratio. The proposed G.L.I model can not only be applied to various ground conditions, but also relieves the tunnel loads by up to 30%.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.3
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• pp.119-126
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• 2001

A process for the production of bioplastics from wastewater with an open microbial culture was developed and evaluated. The process consists of a selection reactor to select bacteria in feast/famine regime and an accumulation reactor to produce PHA using selected bacteria. Polyhydroxyalkanoate(PHAs) accumulating bacteria could be efficiently grown in a sequencing batch reactor(SBR) without any growth limitation. For the high production of PHA limitation such as oxygen and nutrients seemed to be needed. Accumulation experiments were performed to evaluate the level of accumulation of PHA. Limited aeration had no effect, but nutrients limitation showed high accumulation. Bacteria which were selected in the SBR could accumulate PHA till 60% of cellular dry weight in accumulation experiments under nitrogen limitation. PHA accumulation rate decreased with increasing PHA content in the cells. Clearly, PHA accumulation rate has a strong correlation with the PHA content of the cells.