• Journal of Electrical Engineering and Technology
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• v.10 no.1
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• pp.308-313
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• 2015

This paper describes a technique for complete identification of a two-dimensional scattering object and multiple objects immersed in air using microwaves where the scatterers are assumed to be a homogenous dielectric medium. The employed technique consists of initially retrieving the shape and position of the scattering object using a linear sampling method and then determining the electric permittivity and conductivity of the scatterer using adjoint sensitivity analysis. Incident waves are assumed to be TM (Transverse Magnetic) plane waves. This inversion algorithm results in high computational speed and efficiency, and it can be generalized for any scatterer structure. Also, this method is robust with respect to noise. The numerical results clearly show that this hybrid approach provides accurate reconstructions of various objects.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.54 no.1
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• pp.73-80
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• 2018

Intermittent duty of emergency generator has problems emitting large quantities of PM and NOx in exhaust gas. The aim of this study is to propose DPF system which can be applied to medium-large emergency generators. The system is composed of soot dust collector, silencer and filter trap, which is designed to reduce PM emissions at the emergency generator start-up. The pneumatic system controls a flow direction of exhaust gas to pass through the soot collector and filter trap until the engine reaches complete combustion condition. An experiment is performed to measure PM content and concentration to analyze the performance and characteristics of the proposed system.

• Bulletin of the Korean Chemical Society
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• v.23 no.9
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• pp.1309-1338
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• 2002

The fluorescence and photoisomerization quantum yields of trans-1-(9-anthryl)-2-(4-pyridyl)ethene (t-4-APyE), 1-(10-methyl-9-anthryl)-2-(4-pyridyl)ethene (t-4-MeAPyE), and 1-(10-chloro-9-anthryl)-2-(4- pyridyl)ethene (t-4-ClAPyE) were measured in cyclohexane, acetonitrile, and methanol at room temperature.Polar solvents result in the drastic reduction of fluorescence quantum yield and increase of photoisomerization quantum yield for all three compounds. These results are probably due to the stabilization of intramolecular charge transfer (ICT) excited state in polar solvent. The higher contribution of ICT in the presence of more electron-donating methyl substituent, manifested by largest positive fluorescence solvatochromism, indicates that the pyridine ring acts as an electron acceptor. Protonation or methylation makes pyridine ring stronger electron acceptor and causes long-wavelength ground state charge transfer absorption band and complete quenching of fluorescence. The fluorescence from t-4-APyE derivatives can be switched off responding external stimuli viz. medium polarity, protonation, or methylation.

• Journal of Technology Innovation
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• v.12 no.1
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• pp.189-218
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• 2004

In this paper, we estimate consumers' preferences for the key attributes of the future mobile telecommunication terminal using conjoint analysis. For statistical model, we estimate the mixed legit model which can reflect the heterogeneity of consumers' preferences, using the Bayesian approach with Gibbs sampling. The results show that there are large variations in consumers' preferences for the attributes of the future mobile telecommunication terminal, which justifies our using of mixed logit model. Also, the results show that most consumers prefer the medium size display and keyboard as input equipment. Additionally, far from general prediction, the results show that many consumers are indifferent to whether the future mobile telecommunication terminal is able to provide high quality internet service or not, and to operate many application programs and programs originally designed for PC. From those results, we can obtain some important implications for the R＆D strategies. Additionally, the results on the heterogeneity of consumers' preferences reveal that it is possible that the complete device convergence may not happen.

• Journal of Microbiology and Biotechnology
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• v.21 no.8
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• pp.796-801
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• 2011

Corynebacterium tuberculostearicum B146, a strain derived from healthy human skin, contains a medium copy plasmid, p1B146. This plasmid was cloned and its complete nucleotide sequence determined. As a result, p1B146 was found to be 4,2 kb in size with a 53% G+C content, plus six open reading frames (ORFs) were distinguished. According to a computer-assisted alignment, two of the ORFs exhibited significant similarities to already-known common plasmid proteins, the first being the RepA gene, responsible for plasmid replication via a rolling-circle mechanism, and the second being an FtsK-like protein, the function of which remains unclear. The presence and quantity of RNA fragments in the putative ORFs were also evaluated.

• Journal of Microbiology and Biotechnology
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• v.8 no.1
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• pp.67-73
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• 1998

A bacterial strain that excretes hemolysins and proteases into the growth medium was isolated from sea water and designated as KYJ 961. A nearly complete nucleotide sequence of a 16S ribosomal RNA gene from the isolate was determined following the isolation and cloning of amplified genes. On the basis of the 16S ribosomal DNA sequence data, and morphological, chemotaxonomic, and physiological characteristics, strain KYJ 961 was classified as a strain of Bacillus cereus.

• Korean Journal of Microbiology
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• v.19 no.3
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• pp.108-114
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• 1981

In order to isolate microorganisms which produce antibiotics aganist wheat black rust, some bacteria, molds, and actinomycetes were isolated from soils and screened for the production of antibiptics against wheat black rust. Beacuse wheat black rust-puccinia graminis--is a complete parsitic mold which can't grow in artifical medium, new method for the screening of antibiotic producing microorgsnisms against wheat black rust developed by using live leaves of wheat. With new method, a strain No. $480HS_{20}$ which produces a substnace having strong and Puccinia graminis activity and very narrow antimicrobial spectrum was isolated. the substance produced by the strain No.$480HS_{20}$ had better anti Puccinia graminis activity than any other known antifungal antibotics such as kasurgamycin, balasticidins, actidione, antimycin, ologomycin. And the substance was observed to be very stable at heat and ultraviolet light. The strain was indentified as Bacillus subtilis.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2008.10a
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• pp.251-253
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• 2008

Erosion and landslide cause serious damage to forest areas. As a consequence, partial or complete destruction of vegetation occurs, which leads to many cascading problems. In this study, an attempt has been made to identify the forest areas, which are under different risk categories of erosion and landslide, in part of Eastern Ghats of Tamil Nadu. Relevantthematic maps were generated from satellite data, topographical maps, primary and secondary data and weights to each map were assigned appropriately. Weighted overlay analysis was carried out to identify the erosionprone forest areas. The result of erosion and landslide prone model reveals that 4712 ha(17%) of forest area is under high risk category and 15879 ha(58.65%) isunder medium risk category. The results of spatial modeling would be very much useful to the forest officials and conservationist to plan for effective conservation.

• Publications of The Korean Astronomical Society
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• v.9 no.1
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• pp.111-166
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• 1994

I have developed a UV and visible spectroscopic database (UVSD) for atoms and molecules, which are found in interstellar medium, stars, galaxies, and in the atmospheres of the earth, planets, satellites, and comets. This UV and visible database, which is machine-readable, consists of three different sub-databases depending upon the characteristics of the sub-databases: (A) atomic and molecular line listings from laboratory observations or theoretical studies; (B) absorption spectra measured in laboratories; and (C) solar UV, visible, and infrared spectral atlases. The UVSD is in a very initial stage of development compared with other well organized and established infrared and microwave databases. In order to make a good quality and complete database, substantial efforts should be made for the acquisition of scattered important data from laboratories or institutions, and then the acquired heterogeneous data should be peer-reviewed and standardized.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1266-1269
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• 2003

Many studies have indicated that most of a product's cost is fixed early in its lift cycle, before the original design cycle is complete. This implies that we should consider various aspects of product lift cycle at the design stage. This means the need of collaboration in design stage. Because the Internet provides instant access to a wealth of design information, the Internet is used by the collaborative design team members as a medium to share data, information and knowledge, and in some cases for product data management and project management by integrating the Web with appropriate technologies. This paper presents a real-time collaborative design system for powerful interaction performance, based on the Internet and Web technologies. Using The system use the client/server architecture and the purpose of the system is to provide a method that enables real-time view, review and modification of the 3D model through the Internet.