• Journal of Microbiology and Biotechnology
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• v.13 no.6
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• pp.976-983
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• 2003

Seven Escherichia coli cells defective with aerobic growth were isolated by the insertion of ${\lambda}placMu53$, a hybrid bacteriophage of ${\lambda}$ and Mu, which created a transcriptional fusion to lacZY. These insertion mutant cells were tested on an XG ($5-bromo-4-chloro-3-indolyl-{\beta}-D-galactopyranoside$) medium for anaerobic expression of lacZ by fusion to a promoter. The chromosomal DNA from these strains were digested by EcoRI, and the EcoRI fragments that contained the fused gene and lacZ sequence were identified by Southern hybridization, using lacZ containing plasmid as a probe. The EcoRI fragment from each strain was cloned and sequenced. The sequence data were compared with the GenBank database. The mutated gene of three strains, CYT4, CYT5, and OS11, was found to be identical, and it was nrdAB that encoded ribonucleoside diphosphate reductase. The gene nrdAB was at min 50.5 on the Escherichia coli linkage map and 2,348,084 on the physical map, and is involved in hemAe-related reduction-oxidation reaction. OS6 and OS14 mutant strains had insertion at min 8.3 and the mutated gene was hemB. The hemB encodes 5-aminolevulinate dehydratase or porphobilinogen synthase. The OS3 mutant had insertion in cydB at min 16.6. The cydAB encodes cytochrome d oxidase. In the case of OS1, the fusion was made with sucA, the E1 component of ${\alpha}-ketoglutarate$ dehydrogenase.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.3
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• pp.13-18
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• 2011

Sphere Decoding (SD) is a decoding technique able to achieve the Maximum Likelihood (ML) performance in fading environments; nevertheless, the main disadvantage of this technique is its high complexity, especially in poor channel conditions. In this paper, we present an adaptive hybrid algorithm which reduces the conventional Sphere Decoder's complexity and keeps the ML performance. The system called Adaptive OSIC-SD modifies its operation based on Signal to Noise Ratio (SNR) information and achieves an optimal performance in terms of Bit Error Rate (BER) and complexity. Through simulations, we probe that the proposed system maintains almost the same bit error rate performance of the conventional SD, and exhibits a lower, quasi-constant complexity.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.57.2-57.2
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• 2018

We present the preliminary result from our KVN single-dish observations of the MALATANG sample. The MALATANG (Mapping the dense molecular gas in the strongest star-forming Galaxies) is one of the JCMT legacy surveys on the nearest 23 IR-brightest galaxies beyond the Local Group. The goal of the MALATANG survey is to map the sample in the dense gas tracers (HCN and HCO+J=4-3), and probe the relationships between the dense molecular gas and star formation activities. As a complementary study, we recently launched a KVN/KaVA program on the same sample, in order to measure their flux densities and parsec-scale jet/outflows in the millimeter regime, which will be greatly useful in understanding the initial conditions of the feedback process. In this work, we present the preliminary result from our pilot KVN single-dish program on a sub-sample, which will be used to select the future VLBI imaging study under plan. We investigate the KVN spectral energy distributions (SED) of the sample as a function of the power source of the luminous IR brightness of each target (starburst? AGN? or hybrid?). We also discuss the technical challenges that we experienced during our KVN observations due to the large size of the sample in the sky.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.11a
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• pp.4-4
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• 2012

Proteins enable biology to be viable through molecular interactions (such as in antigen-antibody, ligand-receptor, and drug-target) with

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.174-174
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• 2010

Gallium Nitride(GaN) attracts great attention due to their wide band gap energy (3.4eV), high thermal stability to the solid state lighting devices like LED, Laser diode, UV photo detector, spintronic devices, solar cells, sensors etc. Recently, researchers are interested in synthesis of polycrystalline and amorphous GaN which has also attracted towards optoelectronic device applications significantly. One of the alternatives to deposit GaN at low temperature is to use Single Source Molecular Percursor (SSP) which provides preformed Ga-N bonding. Moreover, our group succeeds in hybridization of SSP synthesized GaN with Single wall carbon nanotube which could be applicable in field emitting devices, hybrid LEDs and sensors. In this work, the GaN thin films were deposited on c-axis oriented sapphire substrate by MBE (Molecular Beam Epitaxy) using novel single source precursor of dimethyl gallium azido-tert-butylamine($Me_2Ga(N_3)NH_2C(CH_3)_3$) with additional source of ammonia. The surface morphology, structural and optical properties of GaN thin films were analyzed for the deposition in the temperature range of $600^{\circ}C$ to $750^{\circ}C$. Electrical properties of deposited thin films were carried out by four point probe technique and home made Hall effect measurement. The effect of ammonia on the crystallinity, microstructure and optical properties of as-deposited thin films are discussed briefly. The crystalline quality of GaN thin film was improved with substrate temperature as indicated by XRD rocking curve measurement. Photoluminescence measurement shows broad emission around 350nm-650nm which could be related to impurities or defects.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.5
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• pp.581-587
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• 2005

This paper presents a hybrid face recognition method of both the first moment of image and the independent component analysis(ICA) of fixed point(FP) algorithm based on Newton method. First moment is a method for finding centroid of image, which is applied to exclude the needless backgrounds in the face recognitions by shifting to the centroid of face image. FP-ICA is also applied to find a set of independent basis images for the faces, which is a set of statistically independent facial features. The proposed method has been applied to the problem for recognizing the 48 face images(12 persons o 4 scenes) of 64*64 pixels. The 3 distances such as city-block, Euclidean, negative angle are used as measures when match the probe images to the nearest gallery images. The experimental results show that the proposed method has a superior recognition performances(speed, rate) than conventional FP-ICA without preprocessing. The city-block has been relatively achieved more an accurate similarity than Euclidean or negative angle.

• Earthquakes and Structures
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• v.17 no.2
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• pp.143-162
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• 2019

Motivated by a simpler and more compact hybrid active tuned mass damper (ATMD) system with wide frequency spacing (i.e., high robustness) but not reducing the effectiveness using the least number of ATMD units, the active tuned tandem mass dampers (ATTMD) have been proposed to attenuate undesirable oscillations of structures under the ground acceleration. Likewise, it is expected that the frequency spacing of the ATTMD is comparable to that of the active multiple tuned mass dampers (AMTMD) or the multiple tuned mass dampers (MTMD). In accordance with the mode generalised system in the specific vibration mode being controlled (simply referred herein to as the structure), the closed-form expression of the dimensionless displacement variances has been derived for the structure with the attached ATTMD. The criterion for the optimum searching may then be determined as minimization of the dimensionless displacement variances. Employing the gradient-based optimization technique, the effects of varying key parameters on the performance of the ATTMD have been scrutinized in order to probe into its superiority. Meanwhile, for the purpose of a systematic comparison, the optimum results of two active tuned mass dampers (two ATMDs), two tuned mass dampers (two TMDs) without the linking damper, and the TTMD are included into consideration. Subsequent to work in the frequency domain, a real-time Simulink implementation of dynamic analysis of the structure with the ATTMD under earthquakes is carried out to verify the findings of effectiveness and stroke in the frequency domain. Results clearly show that the findings in the time domain support the ones in the frequency domain. The whole work demonstrates that ATTMD outperforms two ATMDs, two TMDs, and TTMD. Thereinto, a wide frequency spacing feature of the ATTMD is its highlight, thus deeming it a high robustness control device. Furthermore, the ATTMD system only needs the linking dashpot, thus embodying its simplicity.

• Korean Journal of Microbiology
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• v.32 no.1
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• pp.47-52
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• 1994

The cells of Campylobacter jejuni heat-shocked at 48${\circ}C$ for 30 min synthesized the heat shock proteins of HSP90, HSP66 and HSP60. Those heat shock proteins were found to correspond to the heat shock proteins of HSP87, HSP66 (DnaK), and HSP58 (GroEL) of E. coli, respectively. By Southern blot analysis of the chromosomal DNAs of C. jejuni with groESL and dnaK genes of E. coli as DNA probes, the heat shock genes of C. jejuni which are homologous to the E. coli groESL and dnaK genes were found to exist in the chromosomal DNA. The genomic libraries of C. jejuni were constructed with the cosmid vector pWE15 and the groEL gene of C. jejuni were cloned in E. coli B178 groEL44 temperature senstive mutant. The hybrid plasmid (pLC1) was inserted with the DNA fragment (about 5.7kb in size) containing the groEL gene. E. coli groEL44 mutant cell transformed with the pLC1 could grow at 42${\circ}C$ by synthesizing the HSP60 of C. jejuni and regained the susceptibility to the ${\lambda}$ vir phage by expression of the groEL gene in the cloned cells. These indicated that the groEL products of C. jejuni had chaperon effects by synthesizing the heat shock proteins in the cloned cells of E. coli.

• Korean Journal of Plant Tissue Culture
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• v.26 no.3
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• pp.163-169
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• 1999

This study was conducted to produce herbicide resistant plants by transferring phosphinothricin acetyltransferase (PAT) gene into Populus alba $\times$ Populus glandulosa No .3 using Agrobacterium tumefaciens MP 90/PAT. Leaf segments from in vitro grown shoots of hybrid poplar No. 3 were soaked in a AB medium containing Agrobacterium tumefaciens MP 90/PAT for 10 min and cocultivated for 2 days on MS medium containing 1.0 mg/L 2,4-D and 0.2mg/L kinetin (CIM). Putative transformed calli could be selected after cocultivation of leaf segments on CIM supplemented with 50mg/L kanamycin and 500mg/L cefotaxime for 3 weeks. The selected calli were cultured on CIM supplemented with 50 mg/L kanamycin and 500 mg/L cefotaxime for 5~8 weeks before transfer to WPM containing 1.0mg/L zeatin, 0.1mg/L BAP, 50 mg/L kanamycin and 500mg/L cefotaxime for shoot regeneration. Shoots were regenerated from the callus after 4 week cultivation, and the regenerants were grown on the same medium for 7~l0 weeks. The plants rooted on 1/2 WPM containing 0.2 mg/L IBA and 50 mg/L kanamycin. To confirm the gene insertion into plants, GUS activity was detected by histochemical assay in the transformed plants. Finally, the presence of both NPT II and PAT genes from the transgenic plants were confirmed by PCR amplification with the gene specific primers and subsequent PCR-Southern blot with DIG-labeled PAT gene probe. After acclimatization in pots for 4 weeks, the plants were sprayed by 3 mL/L of Basta to test resistance to the herbicide. The transgenic plants remained green, whereas all the control plants died after one week.

• Journal of Apiculture
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• v.32 no.3
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• pp.147-154
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• 2017

Honeybees (Apis mellifera) are common pollinators and important insects studied in agriculture, ecology and basic research. Recently, RDA (Rural Development Administration) and YIRI (Yecheon-gun Industrial Insect Research Institute) have been breeding a triple crossbred honey bee named Jangwon, which have the ability to produce superior quality honey. In this study, we identified a single nucleotide polymorphism (SNP) marker in the genome of Jangwon honeybee, particularly, in the paternal line (D line). Initially, we performed Sequence-Based Genotyping (SBG) using the Illumina Hiseq 2500 in 5 honeybee inbred lines; A, C, D, E, and F; and obtained 1,029 SNPs. Seventeen SNPs for each inbred line were generated and selected after further filtering of the SNP dataset. The 17 SNP markers validated by performing TaqMan probe-based real-time PCR and genotyping analysis was conducted. Genotyping analysis of the 5 honeybee inbred lines and one hybrid line, $D{\times}F$, revealed that one set of SNP marker, AmD9, precisely discriminated the inbred line D from the others. Our results suggest that the identified SNP marker, AmD9, is successful in distinguishing the inbred honeybee lines D, and can be directly used for genotyping and breeding applications.