• Journal of Microbiology
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• v.44 no.1
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• pp.83-91
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• 2006

The sudden appearance and potential lethality of severe acute respiratory syndrome (SARS)-associated coronavirus (SARS-CoV) in humans has resulted in a focusing of new attention on the determination of both its origins and evolution. The relationship existing between SARS-CoV and other groups of coronaviruses was determined via analyses of phylogenetic trees and comparative genomic analyses of the coronavirus genes: polymerase (Orflab), spike (S), envelope (E), membrane (M) and nucleocapsid (N). Although the coronaviruses are traditionally classed into 3 groups, with SARS-CoV forming a $4^{th}$ group, the phylogenetic position and origins of SARS-CoV remain a matter of some controversy. Thus, we conducted extensive phylogeneitc analyses of the genes common to all coronavirus groups, using the Neighbor-joining, Maximum-likelihood, and Bayesian methods. Our data evidenced largely identical topology for all of the obtained phylogenetic trees, thus supporting the hypothesis that the relationship existing between SARS-CoV and group 2 coronavirus is a monophyletic one. Additional comparative genomic studies, including sequence similarity and protein secondary structure analyses, suggested that SARS-Co V may bear a closer relationship with group 2 than with the other coronavirus groups. Although our data strongly suggest that group 2 coronaviruses are most closely related with SARS-CoV, further and more detailed analyses may provide us with an increased amount of information regarding the origins and evolution of the coronaviruses, most notably SARS-CoV.

• Journal of Microbiology and Biotechnology
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• v.24 no.2
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• pp.236-244
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• 2014

The gene encoding ${\alpha}-\small{L}$-arabinofuranosidase (AFase) from Paenibacillus sp. DG-22 was cloned, sequenced, and expressed in Escherichia coli. The AFase gene (abfA) comprises a 1,509 bp open reading frame encoding 502 amino acids with a molecular mass of 56,520 daltons. The deduced amino acid sequence of the gene shows that AbfA is an enzyme consisting of only a catalytic domain, and that the enzyme has significant similarity to AFases classified into the family 51 of the glycosyl hydrolases. abfA was subcloned into the pQE60 expression vector to fuse it with a six-histidine tag and the recombinant AFase (rAbfA) was purified to homogeneity. The specific activity of the recombinant enzyme was 96.7 U/mg protein. Determination of the apparent molecular mass by gel-filtration chromatography indicated that AbfA has a tetrameric structure. The optimal pH and temperature of the enzyme were 6.0 and $60^{\circ}C$, respectively. The enzyme activity was completely inhibited by 1 mM $HgCl_2$. rAbfA was active only towards p-nitrophephenyl ${\alpha}-\small{L}$-arabinofuranoside and exhibited $K_m$ and $V_{max}$ values of 3.5 mM and 306.1 U/mg, respectively. rAbfA showed a synergistic effect in combination with endoxylanase on the degradation of oat spelt xylan and wheat arabinoxylan.

• The Journal of Korea Robotics Society
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• v.12 no.2
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• pp.206-216
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• 2017

This paper proposes a method to simultaneously estimate two degrees of freedom in wrist forces (extension - flexion, adduction - abduction) and one degree of freedom in grasping forces using Electromyography (EMG) signals of the forearms. To correlate the EMG signals with the forces, we applied a multi - layer perceptron(MLP), which is a machine learning method, and used the characteristics of the muscles constituting the forearm to generate learning data. Through the experiments, the similarity between the MLP target value and the estimated value was investigated by applying the coefficient of determination ($R^2$) and root mean square error (RMSE) to evaluate the performance of the proposed method. As a result, the $R^2$ values with respect to the wrist flexion-extension, adduction - abduction and grasping forces were 0.79, 0.73 and 0.78 and RMSE were 0.12, 0.17, 0.13 respectively.

• Smart Structures and Systems
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• v.21 no.1
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• pp.123-137
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• 2018

Structural monitoring is the most important part of the construction and operation of the embankment dams. Appropriate instruments selection for dams is vital, as inappropriate selection causes irreparable loss in critical condition. Due to the lack of a systematic approach to determine adequate instruments, a framework based on three comparable Multi-Attribute Decision Making (MADM) methods, which are VIKOR, technique of order preference by similarity to ideal solution (TOPSIS) and Preference ranking organization method for enrichment evaluation (PROMETHEE), has been developed. MADM techniques have been widely used for optimizing priorities and determination of the most suitable alternatives. However, the results of the different methods of MADM have indicated inconsistency in ranking alternatives due to closeness of judgements from decision makers. In this study, 9 criteria and 42 geotechnical instruments have been applied. A new method has been developed to determine the decision makers' importance weights and an aggregation method has been introduced to optimally select the most suitable instruments. Consequently, the outcomes of the aggregation ranking correlate about 94% with TOPSIS and VIKOR, and 83% with PROMETHEE methods' results providing remarkably appropriate prioritisation of instruments for embankment dams.

• The Plant Pathology Journal
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• v.24 no.3
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• pp.361-364
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• 2008

The complete nucleotide sequences of a Korean isolate of Potato virus X(PVX-Kr) has been determined. Full-length cDNA of PVX-Kr has been directly amplified by long template reverse transcription and polymerase chain reaction(RT-PCR) using virus specific 5'-end primer and 3'-end primer, and then constructed in a plasmid vector. Consecutive subclones of a full-length cDNA clone were constructed to identify whole genome sequence of the virus. Total nucleotide sequences of genome of PVX-Kr were 6,435 excluding one adenine at poly A tail, and genome organization was identical with that of typical PVX species. Comparison of whole genome sequence of PVX-Kr with those of European and South American isolates showed 95.4-96.8% and 77.4-77.9%, in nucleotide similarity, respectively. Sequenced PVX-Kr in this study and twelve isolates already reported could be divided into two subgroups in phylogeny based on their complete nucleotide sequences. Phylogenetic tree analysis demonstrated that PVX-Kr was clustered with European and Asian isolates(Taiwan, os, bs, Kr, S, X3, UK3, ROTH1, Tula) in the same subgroup and South American isolates(CP, CP2, CP4, HB) were clustered in the other subgroup.

• Tribology and Lubricants
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• v.10 no.1
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• pp.14-26
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• 1994

The minimum oil film thickness(MOFT) in the connecting-rod bearing of a 1.5 liter, L-4, gasoline engine is measured up to 5500 rpm and calculated to study the dynamically loaded engine bearing. Short bearing approximation and Mobility method are used for theoretical analysis of oil film characteristics. And cylinder pressure, crank-pin surface temperature and bearing temperature are measured as the input data of theoretical analysis. The MOFT are measured by the total capacitance method(TCM). To improve the reliability of the test results, a reasonable determination method of bearing clearance is introduced and used, and the effects of cavitation and aeration on the test results are neglected. The crankshaft is grounded by means of a slip ring. A scissor type linkage system was developed to measure the MOFT and bearing temperature. The effects of engine speed, load and oil viscosity on the measured and calculated minimum oil film thicknesses are investigated at 1500 to 5500 rpm. From the comparison between the measured and calculated MOFT, it is found that a qualitative similarity exists between them, but in all cases, the measured MOFT are smaller than those calculated.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.5
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• pp.1079-1086
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• 1990

Recently, demand for the experimental analysis of crack, such as arbitrary or distributed ones which has been considered quite difficult to investigate by the theoretical and numerical method, is increasing. Among existent experimental methods applied to the analysis of stress intensity factors, the slab analogy method have the following merits; cracks can be replaced by similarity-shaped rigid body, and the distribution of stress is represented by slab curvature of duly bent specimen. For the accuracy improvement of this method, multi-point selection method was introduced and its accuracy proved by applying this method to the analysis of centrally linear and inclined cracks in a finite plate which are theoretically known. In this paper, moreover, the stress intensity factors of eccentric and skew-symmetric bent cracks were determined by multi-point selection method and newly developed moire tilted master grating method. The results obtained by this method showed good agreement with the reliably theoretical solutions.

• Korean Journal of Microbiology
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• v.30 no.5
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• pp.397-402
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• 1992

The cDNA of RNA segment coding for VP7 of human rotavirus isolated from patient's stool at Seoul area was synthesized, amplified by polymerase chain reaction, field in with Klenow fragment of DNA polymerase I and cloned into pUC19. The cDNA sequence was determined and compared with that of VP7 coding RNA segments of group A rotaviruses isolates in foreign country. Over 90% sequence homology was found with serotyppe I sepcific WA1 and RE9 strains. Comparative analysis of the deduced amino acid sequences within the two variable regions (amino acid residue 87 through 101 and 208 through 221) with WA1 and RE9 strains also showed high degree of sequence similarity with each other.

• Journal of Korean Society of Forest Science
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• v.85 no.2
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• pp.149-157
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• 1996

The applications of multiple criteria decision making(MCDM) methods were investigated to determine the priority order in forest road construction for timber harvesting and silvicultrual activities in 22 regions. In this paper, MCDM methods have five methods from two kinds of models. The one is non-compensatory preference model including maximin and maximax method; the other is compensatory preference model including simple additive weighting method(SAW), hierarchical additive weighting method(HAW) and technique for order preference by similarity to ideal solution(TOPSIS), SAW and TOPSIS methods turned out to be the most adequate for forest road construction priority order among the five methods tested in this study.

• Journal of the Korean Chemical Society
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• v.41 no.2
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• pp.105-112
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• 1997

The smelly nitro compounds were extracted from dried fishes by simultanous distillation and extraction, then were analyzed by GC-MS. Carbon number and order of an amine could be predicted by using retention time and equivalent chain length. Anchovy, codfish, imitation crab meat, cuttle fish, file fish, pollack, shrimp, octopus, harvest fish, and hard-shelled mussel were used for this investigation. Various smelly nitro compounds such as methylamine, acetamide, thiazole, 2-hydroxy isopropylamine, N-methyl pyrroline, piperidine, cyclohexylamine were identified, however, dimethylamine, trimethylamine, diethylamine were not detected. Principal components analysis was applied to GC-MS profiles for pattern recognition of smelly nitro compounds in dried fishes. Multivariate aspects using principal components analysis were very useful for pattern recognition of smelly components, category similarity.