• Journal of The Korean Astronomical Society
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• v.50 no.3
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• pp.51-59
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• 2017

The presence of blue stragglers pose challenges to standard stellar evolution theory, in the sense that explaining their presence demands a complex interplay between stellar evolution and cluster dynamics. In the meantime, mass transfer in binary systems and stellar collisions are widely studied as a blue straggler formation channel. We explore properties of the Galactic open clusters where blue stragglers are found, in attempting to estimate the relative importance of these two favored processes, by comparing them with those resulting from open clusters in which blue stragglers are absent as of now. Unlike previous studies which require a sophisticated process in understanding the implication of the results, this approach is straightforward and has resulted in a supplementary supporting evidence for the current view on the blue straggler formation mechanism. Our main findings are as follows: (1) Open clusters in which blue stragglers are present have a broader distribution with respect to the Z-axis pointing towards the North Galactic Pole than those in which blue stragglers are absent. The probability that two distributions with respect to the Z-axis are drawn from the same distribution is 0.2%. (2) Average values of $log_10(t)$ of the clusters with blue stragglers and those without blue stragglers are $8.58{\pm}0.232$ and $7.52{\pm}0.285$, respectively. (3) The clusters with blue stragglers tend to be relatively redder than the others, and are distributed broader in colors. (4) The clusters with blue stragglers are likely brighter than those without blue stragglers. (5) Finally, blue stragglers seem to form in condensed clusters rather than simply dense clusters. Hence, we conclude that mass transfer in binaries seems to be a relatively important physical mechanism of the generation of blue stragglers in open clusters, provided they are sufficiently old.

• Journal of Korean Clinical Nursing Research
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• v.22 no.2
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• pp.205-216
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• 2016

Purpose: This study was performed to develop a valid and reliable Korean Patient Classification System for Neonatal care nurses (KPCSN). Methods: The study was conducted in tertiary and general hospitals with 1~2 grade according to nursing fee differentiation policy for NICU (neonatal intensive care unit) nurse staffing. The reliability was evaluated for the classification of 218 patients by 10 nurse managers and 56 staff nurses working in NICUs from 10 hospitals. To verify construct validity, 208 patients were classified and compared for the type of stay, gestational age, birth weight, and current body weight. Nursing time was measured by nurses, nurse managers, and nurse aids. For the calculation of conversion index (total nursing time divided by the KPCSN score), 426 patients were classified using the KPCSN. Data were collected from September 5 to October 28, 2015, and analyzed using t-test, ANOVA, intraclass correlation coefficient, and non-hierarchial cluster analysis. Results: The final KPCSN consisted of 11 nursing categories, 71 nursing activities and 111 criteria. The reliability of the KPCSN was r=.83 (p<.001). The construct validity was established. The KPCSN score was classified into four groups; group $1:{\leq}57points$, group 2: 58~80 points, group 3: 81~108 points, and group $4:{\geq}109points$ in the KPSCN score. The conversion index was calculated as 7.45 minutes/classification score. Conclusion: The KPCSN can be utilized to measure specific and complex nursing demands for infants receiving care in the NICUs.

• Parasites, Hosts and Diseases
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• v.51 no.4
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• pp.401-412
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• 2013

Because of an increased number of Acanthamoeba keratitis (AK) along with associated disease burdens, medical professionals have become more aware of this pathogen in recent years. In this study, by analyzing both the nuclear 18S small subunit ribosomal RNA (18S rRNA) and mitochondrial 16S rRNA gene loci, 27 clinical Acanthamoeba strains that caused AK in Japan were classified into 3 genotypes, T3 (3 strains), T4 (23 strains), and T5 (one strain). Most haplotypes were identical to the reference haplotypes reported from all over the world, and thus no specificity of the haplotype distribution in Japan was found. The T4 sub-genotype analysis using the 16S rRNA gene locus also revealed a clear subconformation within the T4 cluster, and lead to the recognition of a new sub-genotype T4i, in addition to the previously reported sub-genotypes T4a-T4h. Furthermore, 9 out of 23 strains in the T4 genotype were identified to a specific haplotype (AF479533), which seems to be a causal haplotype of AK. While heterozygous nuclear haplotypes were observed from 2 strains, the mitochondrial haplotypes were homozygous as T4 genotype in the both strains, and suggested a possibility of nuclear hybridization (mating reproduction) between different strains in Acanthamoeba. The nuclear 18S rRNA gene and mitochondrial 16S rRNA gene loci of Acanthamoeba spp. possess different unique characteristics usable for the genotyping analyses, and those specific features could contribute to the establishment of molecular taxonomy for the species complex of Acanthamoeba.

• Korean Institute of Interior Design Journal
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• v.19 no.4
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• pp.3-10
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• 2010

The purpose of this study is to select and analyze words that represent various emotional states towards a spatial environment. Selecting appropriate words for the sensibility evaluation of a spatial environment is a process of constructing sensibility indicators, so that an accurate selection of sensibility words is very important. To collect basic words for this study, words for expressing sensation, emotional states, and sensibility regarding a spatial environment have been collected first via free association and a literature review of previous studies. In the second stage, the selected words are refined. Fifteen evaluators have participated in the first process of refining words, 140 college students participated in the second process, and than the final list of 277 refined words has been selected. During the third stage, 15 specialists were asked to evaluate the appropriateness of sensibility evaluation words, for that 7 point-scale has been applied. Then, 99 words with an average point of 4.55 or more and a standard deviation of 1.55 or lower were selected. After investigating the similarity in the meanings of the selected words, 55 pairs of contrasting words have been selected as a final list of sensibility evaluation words. During this last stage, 307 college students majoring in related fields were asked to evaluate the appropriateness of sensibility evaluation words for a spatial environment, and 7 point-scale was obtained. A factor analysis, cluster analysis, and multidimensional analysis have been conducted on the data obtained from these survey. According to the results of the factor analysis, the eight important factors are obtained from the sensibility evaluation criteria of a spatial environment(form, texture, function, value, comfort, aesthetics, atmosphere, and affinity). The factors obtained from this study can be used in the beginning stage of evaluating the sensibility factors of a spatial environment. In addition, the results of this study can be used as basic data when constructing a list of evaluation indicators to select various complex sensibility words for a space; or as general indicators when evaluating various spatial design factors.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.4
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• pp.767-780
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• 2015

In recent years, as smart phone penetration rate is growing explosively, new forms of cyber crime data is poured out beyond the limits of management system for cyber crime investigation. These new forms of data are collected and stored in police station but, some of data are not systematically managed. As a result, investigators sometimes miss the hidden data which can be critical for a case. Crime data is usually generated by computer which produces complex and huge data and records many logs automatically, so it is necessary to simplify a collected data and cluster by crime pattern. In this paper, we categorize all kinds of cyber crime and simplify crime database and extract critical clues relative to other cases. Through data mining and network-visualization, we found there is correlation between clues of a case. From this result, we conclude cyber crime data mining helps crime prevention, early blocking and increasing the efficiency of the investigation.

• Toxicological Research
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• v.22 no.2
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• pp.95-102
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• 2006

Exposure to soluble nickel compound produces toxic effects on immune system, but the mechanism of action remains to be elucidated. Differential gene expression was studied to understand the potential molecular mechanism responsible for acute toxicity induced by nickel acetate in spleen cells. We exposed mouse spleen cells to nickel acetate with a nontoxic dose ($40{\mu}M$) and then extracted total RNA at 6 h and 12 h after exposure. The RNA was hybridized onto 10K mouse oligonucleotide microarrays, and data were analyzed using GeneSpring 7.1. Nickel had a modest effects on expression of many genes, in the range of 1.3-3 fold. The expression profile showed time-dependent changes in expression levels of differentially expressed genes, including some important genes related to cell cycle, apoptosis and DNA repair. In hierarchical cluster analysis of duplicate experiments, 111 genes were screened out. Out of these, 44 genes showing time- dependent up-regulation (>1.5 fold) and 38 genes showing down-regulation (>1.5 fold) at all time points were chosen for further analysis. The change in the expression of three genes (GPX1, GADD45B and FAIM) after nickel treatment was validated using RT-PCR. As a rule, a number of genes appear to be coordinately regulated between cell survival and cell death from nickel toxicity. In conclusion, changes in the gene profile in the spleen after nickel treatment are complex and genes with diverse functions are modulated. These findings will be contributed to the understanding of the complicated biological effects of nickel.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.2
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• pp.112-120
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• 2001

Genetic diversity of 47 East-Asian vegetable soybean was characterized by means of agro-morphological traits and RAPD markers. A field trial was conducted to evaluate 14 agro-morphological traits. To study RAPD-based DNA analysis, a total of sixty 10-mer random primers were screened. Of these, 23 polymorphic markers in 16 varieties used for screening. Among 207 markers amplified, 48 were polymorphic for at least one pairwise comparison within the 47 varieties. A higher differentiation level between varieties was observed by using RAPD markers compared to morphological markers. Correspondence analysis using both types of marker showed that RAPD data could fully discriminate between all varieties, whereas morphological markers could not achieve a complete discrimination. Genetic distances between the varieties were estimated from simple matching coefficients, ranged from 0.0 to 0.640 with an average of 0.295$\pm$0.131 for morphological traits and 0.042 to 0.625 with an average of 0.336$\pm$0.099 for RAPD data, respectively. Cluster analysis based on genetic dissimilarity of these varieties gave rise to 4 distinct groups. The clustering results based on RAPDs did not match with those based on morphological traits. Geographical distribution of most varieties in each of the groups were not well defined. The results suggested that the level of genetic diversity within this group of East-Asian vegetable soybean varieties was sufficient for a breeding program and can be used to establish genetic relationships among them with unknown or unrelated pedigrees.

• Journal of Microbiology and Biotechnology
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• v.21 no.4
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• pp.438-447
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• 2011

Deinococcus radiodurans is extremely resistant to various genotoxic conditions and chemicals. In this study, we characterized the effect of a sublethal concentration (100 ${\mu}M$) of cadmium (Cd) on D. radiodurans using a whole-genome DNA microarray. Time-course global gene expression profiling showed that 1,505 genes out of 3,116 total ORFs were differentially expressed more than 2-fold in response to Cd treatment for at least one timepoint. The majority of the upregulated genes are related to iron uptake, cysteine biosynthesis, protein disulfide stress, and various types of DNA repair systems. The enhanced upregulation of genes involved in cysteine biosynthesis and disulfide stress indicate that Cd has a high affinity for sulfur compounds. Provocation of iron deficiency and growth resumption of Cd-treated cells by iron supplementation also indicates that CdS forms in iron-sulfur-containing proteins such as the [Fe-S] cluster. Induction of base excision, mismatch, and recombinational repair systems indicates that various types of DNA damage, especially base excision, were enhanced by Cd. Exposure to sublethal Cd stress reduces the growth rate, and many of the downregulated genes are related to cell growth, including biosynthesis of cell membrane, translation, and transcription. The differential expression of 52 regulatory genes suggests a dynamic operation of complex regulatory networks by Cd-induced stress. These results demonstrate the effect of Cd exposure on D. radiodurans and how the related genes are expressed by this stress.

• Archives of design research
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• v.18 no.1 s.59
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• pp.205-214
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• 2005

A development proposal that maximizes the trend of travel souvenir and articles toward tourism and natural resources through utilization of the Limited Production method was the focus of the present research. First, the flaws of travel souvenir and articles, currently produced in Inje, Kangwon-Do, were identified, as were the regional uniqueness of the area. The comparative advantages of developmental conditions of the above-specified region to various other Si/Kun regions were demonstrated to ascertain the optimal production method of travel souvenir and articles. The results are as follows. Superior supply of,7aw materials necessary for production of wood-worked travel souvenir and articles are abundantly available and the dose proximity of 17 existing workshops self-contain the production capacity to sustain the Limited Production method. Furthermore, the regional governing council conveyed positive attitudes towards the prospect of creating a regional production complex of wood-worked travel souvenir and articles. The results demonstrate that the optimal method of maximizing the trend of travel souvenir and articles toward tourism and natural resources is achieved through systematic collaboration of industry, education, and tourism that promote development, production, and merchandising of Inje's regional travel souvenir and articles.

• Journal of Electrical Engineering and Technology
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• v.10 no.5
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• pp.2179-2188
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• 2015

Recently, many researches have been done to solve the challenging problem of Blind Source Separation (BSS) problems in the underdetermined cases, and the “Two-step” method is widely used, which estimates the mixing matrix first and then extracts the sources. To estimate the mixing matrix, conventional algorithms such as Single-Source-Points (SSPs) detection only exploits the sparsity of original signals. This paper proposes a new underdetermined mixing matrix estimation method for time-delayed mixtures based on the receiver prior exploitation. The prior information is extracted from the specific structure of the complex-valued mixing matrix, which is used to derive a special criterion to determine the SSPs. Moreover, after selecting the SSPs, Agglomerative Hierarchical Clustering (AHC) is used to automaticly cluster, suppress, and estimate all the elements of mixing matrix. Finally, a convex-model based subspace method is applied for signal separation. Simulation results show that the proposed algorithm can estimate the mixing matrix and extract the original source signals with higher accuracy especially in low SNR environments, and does not need the number of sources before hand, which is more reliable in the real non-cooperative environment.