• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1143-1149
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• 2003

To elucidate a method of preventing dental caries, strains producing lytic enzymes were isolated and their characteristics were investigated. Among 5,00 alkalophilic strains isolated from soil, 22 strains showed lytic activity against Streptococcus mutans. Strain No. 4830, with the highest lytic activity, was selected for further study. Strain 4830 showed 94% sequence homology with the 16S rDNA sequence of Bacillus alcalophilus, but it was concluded to be different from Bacillus alcalophilus because of its biochemical characteristics. The strain was named Bacillus sp. 4830. The lytic enzyme from Bacillus sp. 4830 was purified by ethanol precipitation and CM-agarose column chromatography. The molecular weight of the lytic enzyme was determined to be 28 kDa by SDS-PAGE. The lytic enzyme was stable between pH 5.0 and pH 11 and up to $40^{\circ}C$. The optimal pH and temperature for the lytic activity was 9.0 and $50^{\circ}C$, respectively.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.12
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• pp.2762-2770
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• 2012

In this paper, we propose a novel approach to effectively compress the sub-images transformed from the picked-up elemental images in integral imaging, in which motion vectors of the object in each sub-image are fast and accurately estimated and compensated by combined use of MSE(mean square error)-based TSS(tree-step search) and FS(full search) schemes. This is, the possible object areas in each sub-image are searched by using the fast TSS algorithm in advance, then the these selected object areas are fully searched with the accurate FS algorithm. Furthermore, the sub-images in which all object's motion vectors are compensated, are transformed into the residual images by using the difference image method and finally compressed with the MPEG-4 algorithm. Experimental results reveal that the proposed method shows 214% improvement in the compression time per each image frame compared to that of the conventional method while keeping the same compression ratio with the conventional method. These successful results confirm the feasibility of the proposed method in the practical application.

• Journal of Life Science
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• v.27 no.7
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• pp.746-753
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• 2017

In order to rapidly identify four drums species, Larimichthys polyactis, L. crocea, Atrobucca nibe, and Pseudotolithus elongates, a highly efficient and quick method has been developed using multiplex polymerase chain reaction (PCR) with species-specific primers. Around 1.4 kbp of the mitochondrial COI gene sequences from the four drums species were aligned, and species-specific forward primers were designed, based on the single nucleotide polymorphism (SNP). The optimal conditions for PCR amplification were selected through cross-reactivity, using a gradient PCR method. The PCR results demonstrated species-specific amplification for each species at annealing temperatures between 50 and $62^{\circ}C$. Multiplex species-specific PCR (MSS-PCR) amplification reactions with four pairs of primers were performed for sixteen specimens of each species. MSS-PCR lead to a species-specific amplification of a 1,540 bp fragment in L. polyactis, 1,013 bp in A. nibe, 474 bp in L. crocea, and 182 bp in P. elongates, respectively. The four different sizes of each PCR product can be quickly and easily detected by single gel electrophoresis. The sensitivity of the MSS-PCR of the DNA was up to $0.1ng/{\mu}l$ as a starting concentration for the four different species tested. These results suggest that MSS-PCR, with species-specific primers based on SNP, can be a powerful tool in the rapid identification of the four drums species, L. polyactis, L. crocea, A. nibe, and P. elongates.

• Journal of The Korean Association For Science Education
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• v.36 no.3
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• pp.509-517
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• 2016

Previous studies have investigated the similarity between the development of evolutionary explanations and students' conceptual developments on evolution. However, the validity and reliability of the assessment method reflecting the similarity have not been quantitatively examined yet. In addition, no study has examined the conceptual progressions of evolution concept based on contexts although literature has addressed the contextual difference of evolutionary explanation in the history of science. This study examined the validity and reliability of history-of-science-based evolution concept assessment using ordered multiple choice (OMC) methods and Rasch analysis and explored conceptual progression by three contexts (e.g., human, animal, and plant). The evolution concept assessment developed by Ha (2007) was used to examine 1711 elementary, middle, and high school students, and pre- and in-service science teachers' (biology majors and non-majors) evolution concepts. Internal consistency reliability and item response fitness of the OMC method that provide 0- to 4-point scores to creationism, teleology, intentionality, use/disuse, and natural selection respectively met the benchmark based on the Cronbach alpha and MNSQ indices of Rasch analysis. The level of elementary and middle school students' evolution concepts were located between intentionality and use/disuse while the level of high school and non-biology science teachers' evolution concepts were located between use/disuse and natural selection. The conceptual progressions of evolution concepts were differentiated according to three contexts. This study provided the quantitative evidence for the similarity between the development of evolutionary explanations and students' conceptual developments on evolution and suggest new analysis methods (i.e., OMC) of evolution concept assessment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.304-310
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• 2017

This study is a methodological research study that tests the validity and reliability of the NCRC (Nurse Clinical Reasoning Competence scale), an instrument developed by Liou and his colleagues as the basic data for enhancing the clinical reasoning competence of nurses, by translating it into Korean and checking the similarity of the sentence structure and meaning (between the two versions?). This study verified its validity and reliability by examining 166 nurses working in four tertiary hospitals located in Seoul and Busan. An analysis of the content validity by experts showed that all of the items have a content validity higher than CVI 0.8. From the exploratory and confirmatory factor analysis, it was found that the instrument includes a total of 15 items consisting of one factor. In addition, the correlation with the Korean version of the Nurse Clinical Reasoning Competence scale is confirmed to test the concurrent validity, by using a measurement tool of nurses' critical thinking dispositions and clinical decision-making abilities (correlation coefficient =.55-.64(p<.001) and Cronbach's ${\alpha}=.93$). Thus, the Korean version of the NCRC may be a useful instrument for evaluating the clinical reasoning competence of Korean nurses and providing the basic data for assessing their clinical reasoning competence and developing their promotion strategies.

• The Journal of the Petrological Society of Korea
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• v.25 no.3
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• pp.299-310
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• 2016

The Stele for Buddhist Monk Wonjong at Godalsa Temple Site was destroyed a long time ago. Only the tortoise-shaped pedestal and the ornamental capstone in the form of a hornless dragon remain at the site and the broken stele body is stored at the National Museum of Korea today. The stele is made of two kinds of rocks that are coarse-grained biotite granite for the pedestal and the capstone, and fine-grained biotite granite including hornblende assemblages and feldspar phenocrysts for the stele body. The coarse-grained biotite granite of the pedestal and capstone showed same magnetic susceptibility and lithological characteristics with biotite granite outcrops in Yeoju area, whereas the fine-grained granite of the stele body did not. To find a provenance of the stele body stone, we investigated Korean granites in terms of magnetic susceptibility, lithology and old recordings about construction process of the stele. As a result, Haeju granite is the most likely to be a cognate rock of the stele body stone as it has same texture and lithological characteristics like color, hornblende assemblages, mineral composition and magnetic susceptibility. It is imported from Haeju (North Korea) to South Korea via China commercially, and the most suitable for a replica stone of the stele body.

• Korean Journal of Microbiology
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• v.55 no.3
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• pp.313-315
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• 2019

An anaerobic bacterial strain WCF-2 was isolated from cow dung in finding cellulose-degrading bacteria for use as silage additives. Strain WCF-2 showed a higher cellulolytic activity than Cellulosilyticum lentocellum DSM $5427^T$, the closest relative of strain WCF-2 (98.2% of 16S rRNA gene sequence similarity). We sequenced the complete genome of strain WCF-2 and compared it with that of C. lentocellum DSM $5427^T$. The OrthoANI value between the two strains was 97.9% thus strain WCF-2 was identified as C. lentocellum. The genome size of strain WCF-2 was 4,779,774 bp with a G + C content of 34.4%, 4,154 coding genes (CDS), 54 pseudo genes, and 142 RNA genes. Strain WCF-2 harbored seven cellulase genes, five of which showed low similarities with those of C. lentocellum DSM $5427^T$.

• Economic and Environmental Geology
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• v.56 no.2
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• pp.201-215
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• 2023

In the stone-lined tombs from Cheongyang Rokpyeong-ri site, several stone-lined tombs corresponding to the Three Kingdoms Period, Unified Silla Period and Goryeo Dynasty were excavated. In this study, the stone properties of petrological, mineralogical and geochemical characteristics from 15 stone-lined tombs were analyzed, the rock species and occupation rate were reviewed, also the provenance area was interpreted. There are five types of rocks used as members of the tombs, including black sandstone, greywacke, slate, conglomerate and gneiss. As a result of magnetic susceptibilities, the rocks of the tombs and presumed provenance are all shown in the same range, and the similarity between the tombs and the source area is high in geochemical behavior characteristics. The stone properties of the tombs are the same as the presumed provenance rocks and is distributed within a 500m around the bedrock of the tombs in the excavation site, so it seems that self-sufficiency was possible on the site without a special procurement system. These stones are interpreted to have been constructed through some trimming without any special technique, but some stone tombs have been confirmed to used homogeneous black sandstone at the bottom of the tombs, so it is believed that there were artificial selection of stones.

• Korean Journal of Culture and Social Issue
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• v.29 no.4
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• pp.595-616
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• 2023

The Critical Consciousness Scale (CCS) is a scale developed by Diemer and colleagues (2017) that can measure the capacity of the oppressed or marginalized people to critically analyze their social and political conditions, support societal equality, and take action to change the perceived inequities. In this study, we validated the CCS for Korea by adapting and localizing the scale and validating it among university students. Content validity was verified by having five individuals with master's and doctoral degrees in psychology evaluate the suitability of the translated items. Afterwards, reliability and validity were verified through a survey of 314 university students nationwide using the CCS, along with the opportunity inequality recognition scale, recognition of the need for environmental change scale, social participation scale, and belief in a just world scale. To verify the scale's validity, exploratory factor analysis was conducted, confirming three subfactors. Then, a confirmatory factor analysis was carried out, where 14 items out of the original 22 were retained. The construct validity and reliability of these 14 items were found to be satisfactory. Additionally, in the correlation analysis between the CCS and similar scales, a significant clear relationship was found. The CCS showed a positive correlation with scales such as opportunity inequality recognition, need for environmental change recognition, and social participation, and a negative correlation with the belief in a just world scale. Based on these results, the CCS can be considered valid and reliable. Finally, the limitations and significance of this study were discussed.

• Journal of Korean Society for Geospatial Information Science
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• v.24 no.4
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• pp.75-81
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• 2016

This study focused on exploring real transaction price of apartment and spatial and temporal heterogeneity of the variables that influence real transaction price of apartment from the spatial and temporal perspective. As independent variables that are considered to influence real transaction price of apartment, transport, local characteristics, educational conditions, population, and economic characteristics were taken into account. Accordingly, the influence of independent variables and spatial distribution pattern were analyzed from the global and local aspects. The spatial and temporal changing patterns of real transaction price of apartment which is a dependent variable were analyzed. First, to establish an analysis model, OLS analysis and GWR analysis were conducted, and thereby more efficient and proper model was selected. Secondly, to find spatial and temporal heterogeneity of independent variables with the use of the selected GWR model, Local $R^2$ was used for local analysis. Thirdly, to look into spatial distribution of independent variables, kriging analysis was carried out. Therefore, based on the results, it is considered that it is possible to carry out more microscopic housing submarket analysis and lay the foundation for establishing a policy on real property.