• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.94-99
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• 1991

- The further study for the identification of the previously reported pink-pigmented facultative methylotrophic bacterium (PPFM) GL-10 was carried out. The PPFM GL-10 was Gram nagative, rod, and motile by a single polarly inserted flagellum. The colonies were smooth, pink, circular, along with convex with entire margin. The isolate could utilize C1 compounds and a variety of multicarbon substrates as sole carbon and energy source. The isolate was obligately aerobic, and exhibited both catalase and oxidase activities. The deoxyribonucleic acid base composition was 65-67 mol% guanine plus cytosine. The isolate was mostly identical with Methylobacterium extorquens and named Methylobacterium sp. strain GL-10. Methylobacterium GL-10 accumulated a copolyester of 3-hydroxybutyrate and 3-hydroxyvalerate (poly-3HB/3 HV) when grown in nitrogen-free culture media containing sodium propionate as substrate at the second polyester accumulation stage. The composition of copolyester, as determined from $^1h$ NMR spectra, was 23 mol% of 3-hydroxyvalerate (3HV).

• Journal of Computational Design and Engineering
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• v.3 no.1
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• pp.71-90
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• 2016

Steel nitriding is a thermo-chemical process leading to surface hardening and improvement in fatigue properties. The process is strongly influenced by many different variables such as steel composition, nitrogen potential, temperature, time, and quenching media. In the present study, the influence of such parameters affecting physic-chemical and mechanical properties of nitride steels was evaluated. The aim was to streamline the process by numerical-experimental analysis allowing defining the optimal conditions for the success of the process. Input parameters-output results correlations were calculated through the employment of a multi-objective optimization software, modeFRONTIER (Esteco). The mechanical and microstructural results belonging to the nitriding process, performed with different processing conditions for various steels, are presented. The data were employed to obtain the analytical equations describing nitriding behavior as a function of nitriding parameters and steel composition. The obtained model was validated, through control designs, and optimized by taking into account physical and processing conditions.

• Proceedings of the Mineralogical Society of Korea Conference
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• 2005.05a
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• pp.50-57
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• 2005

Although the bulk composition of materials is one of the major considerations in extractive metallurgy and environmental science, surface composition and topography (edges and dislocations are preferred sites for physicochemical reactions) control surface reactivity, and consequently play a major role in determining metallurgical phenomena and pollution by heavy metals and organics. An understanding of interaction mechanisms of different chemical species with the mineral surface in an aqueous media is very important in natural environment and metallurgical processing. X-ray photoelectron spectroscopy (XPS) has been used as an ex-situ analytical technique, but the material to be analyzed can be any size from $100{\mu}m$ up to about 1 cm. It can also measure mixed solids powders, but it is impossible to ascertain the original source of resulting x-ray signals where they were emitted from, since it radiates and scans the macro sample surface area.

• Journal of the Korean Institute of Rural Architecture
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• v.16 no.1
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• pp.71-78
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• 2014

The purpose of this study is to clarify the actual condition of the plan of middle schools in the rural area. Recently, many middle schools are remodeling the buildings and facilities based on the department system. This study, through analyzing on 3 cases of middle school in korea and japan. This article discuses about the basic characteristics of the plan composition and the education programs of 3 middle schools. The results of this study are summarized as follows; Home room and home base should be more faithfully. Various common space is needed to comfortable school life of students. In case of side corridor type plane, moving path is much needed. Most of them take horizontal zoning system in the department system of middle schools. Media space is very important to enhance the characteristics of each subject zone.

• Journal of the Korean Operations Research and Management Science Society
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• v.19 no.1
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• pp.99-112
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• 1994

An important modelling requirement for multimedia systems is the representation of temporal constraints among several different media that ordinarily arise in multimedia application. The multimedia system which integrates various types of data is required to express voice, image, text and graphic data with simultaneousness or an arbitrary time intervals. The purpose of this study is to analyze the temporal reationships and synchronization among several different kinds of medium. Moreover, it proposes a Multimedia Display-Time Composition Model (MDTC Model) which guarantees a representation of any kind of temporal synchronization among more than two kinds of medium. The proposed model is applied to a company advertizing system. Finally, a multimedia authoring tool based on the MDTC Model is implemented.

• Microbiology and Biotechnology Letters
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• v.22 no.5
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• pp.453-458
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• 1994

Intestinal microbial flora comprise one third of the large intestinal contents in human. They play a significant effects through beneficial and harmful action on the human health. This is the first study which examined the composition of the microflora of the general population in Korea. Bacteroides, Bifidobacterium, Eubacterium, Peptostreptococcus, Lactobacillus, Streptococcus, Escherichia coli, Staphylococcus, Clostridium perfringens, total aerobic bacteria and total anaerrobic bacteria were counted using various selective and non-selective media. Among the bacteria studied the number of Bifidobacterium were greatest in breast-fed infants(30-90 days old), whereas Streptocuccus and Bifidobacterium in bottle-fed infants. In 20-40 age group Bacteroides were predominant followed by Bifidobacterium and Eubacterium. In early group(over 65 years old) Bacteroides were predominant followed by Eubacterium and bifidobacterium. The frequency and number of Cl. perfringens were highest in dlderly group. These results confirm that the microfloral pattern in large intestine change during the life cycle of humans.

• Journal of the Optical Society of Korea
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• v.15 no.2
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• pp.124-127
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• 2011

Quantum dots were designed within a GRIN-SCH(Graded index - Separate confinement Heterostructure) heterostructure to create a high power InAlAs/AlGaAs laser diode. 808 nm light emission was with a quantum dot composition of In0.665Al0.335As and wetting layer composition of Al0.2Ga0.8As by LASTIP simulation software. Typical characteristics of GRIN structures such as high confinement ratios and Gaussian beam profiles were shown to still apply when quantum dots are used as the active media. With a dot density of 1.0x1011 dots/cm2, two quantum dot layers were found to be good enough for low threshold, high-power laser applications.

• Electrical & Electronic Materials
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• v.1 no.1
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• pp.62-69
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• 1988

Te-thin films were highly proper material for optical recording media, but has the demerit of short archival life time due to the unstability to humidity. In order to restrain the degradation, Te$_{100-x}$Se$_{x}$ alloys adding Se stable for the humidity were fabricated. Primarily, to measure the degradation rate with varing the composition of Se to x=5, 10, 14, 25 at.% at Te$_{100-x}$ Se$_{x}$, the change of light transmittance was used in various temperature-humidity environments. As the results, it was showed that Se$_{86}$Te$_{14}$ thin was the most proper composition for the improvement of degradation restraint.int.int.

• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.240-247
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• 1997

Bacillary is the most common form of H. pylori observed during human infection. However, it is known that the morphology change of H. pylori from bacillary to coccoid can be occurred with a response to the environmental stresses such as the nutrient depletion, accumulation of toxic metabolites, pH alteration, and exposure to antimicrobial agents. The coccoid form of H. pylori, which is viable but non-culturable in vitro, seems to be the major cause of antibiotic resistancy and high reinfectability of H. pylori. In this regard, we studied the environmental factors that can induce the morphological change in vitro of H. pylori, and the change of fatty acid composition of plasma membrane. The morphological change from bacillary to coccoid could be observed with the depletion of nutrients, pH variation and reactive oxygen species added in the culture media. This morphologic conversion was paralleled by a dramatic decrease in unsaturated fatty acids and an increase in saturated fattv acids of plasma membrane. The change in composition of membrane fatty acid seems to be a kind of protection mechanism of H. pylori against these environmental stresses.

• Journal of the Korean Institute of Educational Facilities
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• v.18 no.4
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• pp.25-32
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• 2011

This study was carried out to obtain basic data for architectural plans about factors on the facilities relocation needed in management of variation type. For this, floor plans of thirteen middle schools located in Korea and Japan were compared. The results showed a successful conversion to block system according to each subject after remodeling in the schools of our country, however, a monotonous spacial composition excluded other spaces such as media space, teachers' station and preparation room was also shown. These mentioned spaces were important factors in the investigated schools of Japan. By the results of the spacial composition about each space required to the management of variation type, a space share of supplemental areas for learning activities and movement, had shown comparatively low share before remodeling, was improved to 6% and 11.6%, respectively. However, the spacial share of two areas were 16.8% and 12.9%, respectively, in the schools of Japan and it meant the distribution of area was more even than the cases of our country.