• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.9
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• pp.1451-1456
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• 2003

In code roll forming processes, the sheet metal strip is gradually and successively bent into a desired profile. Occurrence of buckling is one of the major defects. Buckling may occur due to longitudinal stress and it is difficult to predict buckling behavior. In this study an analytical method for buckling behavior during roll forming is proposed. All numerical simulations are performed by finite element analysis. The behavior of buckling can be predicted with the simulation modeling of the finite element method.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.04a
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• pp.73-73
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• 2003

Bacillus thuringiensis 2385-1, which showed toxicity to lepidopteran but not to dipteran was isolated from Korean soil sample and characterized. The H-serotype of 2385-1 was identical to that of serovar kenyae (H4a4c), and its crystal toxin was bipyramidal-shaped with a molecular weight of 130 kDa. However, the plasmid profile of 2385-1 was different from that of serovar kenyae. (omitted)

• Journal of the Korean Society of Safety
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• v.23 no.6
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• pp.115-121
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• 2008

By bond mechanism between the prestressing strand and the concrete surrounding it, the effective force of prestressing must be transferred to the concrete entirely. The distance required to transfer the effective force of prestressing is called the transfer length, and the development length is the bond length required to anchor the strand as it resists external loads on the member. Transfer length was determined from the concrete strain profile at the level of the strands at transfer and development length was determined from various external loading lengths and compared with current code equation. Through the test results, bond failure is predicted based on the distress caused by cracks when they propagate within the transfer zone of prestressing strand. The current code equation was found to be conservative in comparison with the measured value.

• Applied Microscopy
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• v.51
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• pp.10.1-10.9
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• 2021

We investigate the sensitivity of symmetry quantification algorithms based on the profile R-factor (R_p) and the normalized cross-correlation (NCC) coefficient (γ). A DM (Digital Micrograph^©) script embedded in the Gatan digital microscopy software is used to develop the symmetry quantification program. Using the Bloch method, a variety of CBED patterns are simulated and used to investigate the sensitivity of symmetry quantification algorithms. The quantification results show that two symmetry quantification coefficients are significantly sensitive to structural changes even for small strain values of < 1%.

• The Journal of the Korean Society for Microbiology
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• v.35 no.2
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• pp.171-180
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• 2000

Ninety two strains of Streptococcus pyogenes were isolated from patients with pharyngitis, scarlet fever, skin infection, and invasive streptococcal infections in Seoul, Korea from January to December, 1998. All isolates were epidemiologically characterized by T protein serotype, and serum opacity factor (OF) detection to phenotypes. To analyze the genetic relationship, fifty two isolates including 32 erythromycin-clindamycin (Em-Cm) resistant strains, 20 antimicrobial susceptible strains were attempted to the pulsed-field gel electrophoresis (PFGE). T protein serotype showed 16 kinds in distribution including T12 and T4. Among the total isolates, 40 strains (43.5%) belonged to the T12 serotype and twenty strains (21.7%) to T4 serotype. On the other hand, when infection aspect of S. pyogenes isolates were analysed by T serotype distribution, T12 type was predominant for pharyngitidis which contributed to 21 strains (53%) and for skin infection isolates which contributed to 11 strains (28%), respectively. In case of T4 type, it was the most predominant pharyngitidis isolates which contributed to 8 strains (40%). In T serotype distribution of Em-Cm resistant strains, 27 strains (84%) of the thirty two showed T12 serotype. In minimum inhibitory concentration (MIC) values of Em-Cm resistance isolates, thirty two isolates showed resistant to erythromycin 27 strains (84%), had high MIC of >$128\;{\mu}g/ml$. And also to clindamycin, twenty two strains (69%) had high MIC of >$128\;{\mu}g/ml$. When OF detection of Em-Cm resistance of S. pyogenes isolates were analyzed by T serotype distribution, T12 serotype isolates revealed that all of the isolates except one strain were OF negative. In PFGE profile analysis to Em-Cm resistance isolates, of the twenty seven, Em-Cm resistance of T12 serotype isolates, 26 strains showed identical PFGE profile and all of these isolates revealed that OF negative. Eighty four percent of Em-Cm resistance S. pyogenes isolates had identical phenotype and PFGE profile. These results strongly suggested that the Em-Cm resistant S. pyogenes isolates from Seoul area showed close genetic correlation and PFGE could be available tool for molecular epidemiology.

• Journal of Mushroom
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• v.7 no.3
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• pp.130-134
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• 2009

To develop new white variety of Oyster mushroom, all white varieties which have been collected and kept in the lab were revived and screened their cultural characteristics. 84 intra-specific Oyster mushroom hybrids between the white-colored mutants Suhan and Wonhyeong were developed using hyphal anastomosis technique in 2007. The Po2007-63 ($2842-7{\times}0205-7$) was shown the best cultural characteristics, selected to be a new variety and named as 'Goni'. The new commercial strain, 'Goni' has white pilei and grows well under spring and autumn conditions in Korea. The fruiting bodies of 'Goni' are of an excellent quality in that not only the stipe is thick and long but also the pileus is small and hard. The optimum temperatures for mycelial growth and fruiting body development were $25-30^{\circ}C$ and $10-16^{\circ}C$, respectively. Time period required for the initiation of the first fruiting body is about 3 to 5 days depending on the temperatures. The shape of fruiting body is thin funnel shape. Fruiting body production per bottle was about $91{\pm}13$ g which is almost 97% quantity compared to that of other variety 'Miso'. Relatively low temperature incubation ($11^{\circ}C$) resulted in the development of better quality of 'Goni' mushrooms. When two different media including potato dextrose medium and mushroom complete medium were compared, the growth of mushroom were much faster in mushroom complete medium at $20-25^{\circ}C$, but not at $25^{\circ}C$. Similar results were observed with other variety 'Miso'. Analysis of the genetic characteristics of the new commercial strain 'Goni' showed a major DNA profile as that of the parental Suhan when primer URP 1 was used, but different to 'Miso' that was used as a control. When screens were performed with primer URP 2, DNA patterns were similar both to that of the parents and 'Miso'. This new variety of the white Oyster mushroom has a clean and fresh image that corresponds well to "health food". We therefore expect that this new strain will satisfy the consumers demand for variety and excellent mushrooms.

• Applied Chemistry for Engineering
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• v.24 no.6
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• pp.628-632
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• 2013

Arthrospira platensis (A. platensis) is an economically important microalgae because it has carbohydrates, lipids, proteins and a number of phytochemicals. It is also a valuable source used in the production of biodiesel and functional foods. In this study, A. platensis was exposed to electron beam irradation (240 kGy) and induced random mutagenesis for strain improvement. Several mutants were obtained, and the resulting mutant was designated as EB29. The growth rate and chlorophyll content of EB29 was similar to those of wild type. However, the lipid content of EB29 was increased seven-fold compared to that of wild type when comparing the nile red fluorescent intensity. Semi-quantitative analysis of EB29 using the calibration plot of standard lipid, triolein, represented $78.6{\mu}g/mL$, which increased 2 times compared to wild type ($41.4{\mu}g/mL$). When analyzing the fatty acid profile of EB29, polyunsaturated fatty acids (PUFAs), such as gamma-linolenic acid (GLA) in EB29 increased about six-fold. Moreover, fatty acids affecting the quality of biodiesel increased compared to that of wild type. Thus, electron beam could be used for the strain improvement of microalgae in order to accumulate PUFAs and alteration of fatty acid profile for biodiesel.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.5
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• pp.677-679
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• 2001

Effect of Growell a herbomineral premix was evaluated on performance, organ weight, humoral immune response, tissue and serum trace element profile of boilers. Day old 50 Babcock broiler chicks were randomly divided in two groups (C and T) and reared on deep litter system for 6 weeks of age. Chicks from group C were given basal diet while chicks from T group were fed basal diet supplemented with Growell at the rate 0.35 g/Kg. The chicks were vaccinated with Lasota strain of NCDV at $4^{th}$ and $28^{th}$ day of age. The birds receiving Growell treatment had higher body weight with better feed conversion ratio as compare to that of control chicks. Growell treatment had significantly reduced per cent weight of spleen and kidney, whereas that of bursa was increased. There was no effect of treatment on relative weight of thymus. HI antibody titer against NCDV in Growell treated chicks were higher as compare to untreated chicks indicating better humoral immune status. Growell treatment had no effect on serum Fe and Zn concentration. Dietary supplementation of Growell had significantly increased iron content of liver, kidney and muscle; zinc content of kidney and muscle; copper content of kidney and muscle and Mn content of kidney. Growell treatment improved the body weight, FCR and humoral immune status of broilers. Similarly, deposition of trace minerals in various organs was also increased in comparison to control.

• Transactions of Materials Processing
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• v.15 no.6 s.87
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• pp.445-452
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• 2006

In most of automobile body panel manufacturing, trimming process is generally performed before flanging. To find feasible trimming line is crucial in obtaining accurate edge profile after flanging. Section-based method develops blank along manually chosen section planes and find trimming line by generating loop of end points. This method suffers from inaccurate results of edge profile. On the other hand, simulation-based method can produce more accurate trimming line by iterative strategy. In this study, new fast simulation-based method to find feasible trimming line is proposed. Finite element inverse method is used to analyze the flanging process because final shape after flanging can be explicitly defined and most of strain paths are simple in flanging. In utilizing finite element inverse method, the main obstacle is the initial guess generation for general mesh. Robust initial guess generation method is developed to handle genera] mesh with very different size and undercut. The new method develops final triangular mesh incrementally onto the drawing tool surface. Also in order to remedy mesh distortion during development, energy minimization technique is utilized. Trimming line is extracted from the outer boundary after finite element inverse method simulation. This method has many advantages since trimming line can be obtained in the early design stage. The developed method is verified by shrink/stretch flange forming and successfully applied to the complex industrial applications such as door outer flanging process.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.283-283
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• 2017

The objective of the present study is to analyze the lactic acid bacteria (LAB) effects on rye silage fermentation at different stages. Different stages (Booting, Heading, Flowering, and Late flowering stage) of rye were collected from the National livestock farm, National Institute of Animal Science, South Korea. Rye sample was inculcated with lactic acid bacteria and incubated at the anaerobic condition for three months. The nutrient profile such as crude protein (CP), Acid detergent fibre, Neutral detergent fibre and total digestibility nutrients were increased in both control and LAB inculcated samples at all the stages of rye forage. The pH of rye silage was reduced at both stages by LAB inoculation as compared with control. The lactate content was increased in all stages of rye sample by LAB. The acetate concentration and butyrate was reduced in LAB inoculated rye sample. However, acetate concentration was slightly high in LAB inculcated rye at heading and late flowering stage. The LAB population was greater in LAB inoculated rye sample as compared with control sample. However, the massive population was noted in booting stage of rye than the other stages. It indicates the inoculated LAB is the main reason for increasing fermentation quality in the sample through pH reduction by lactate production. Overall results suggest that the isolated lactic acid bacterium is the potent strain that could be suitable for rye forage fermentation at different stages.