• Journal of The Korean Astronomical Society
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• v.31 no.2
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• pp.95-99
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• 1998

We report preliminary results of an on-going survey of optically selected barred galaxies with $^{12}CO$(J=1-0) line. The entire sample is composed of about 100 bright barred galaxies ($B_T{\le}13$) with small inclination angle. Most of the galaxies are relatively nearby with receding speed less than 10,000 km/sec. In the first observing run, we have observed central parts of 18 galaxies and detected CO emissions from 5 galaxies (NGC521, 2525, 4262, 4900, and 7479). Most of these galaxies are not observed with CO previously, except for NGC7479 which has been studied at various wavelengths. The peak antenna temperature of detected galaxies ranges from about 30 to 300 mK.

• Perspectives in Nursing Science
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• v.10 no.1
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• pp.77-86
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• 2013

Purpose: The purpose of this study was to describe hospital nurses' lived experience of being a preceptor in Korea. Methods: The data were collected in three focus group interviews with 15 nurses in one general hospital. The phenomenological analytic method suggested by Colaizzi was used to analyze the data. Results: Five theme clusters and 11 themes emerged from the analysis. The five themes include "inevitable rite of passage for an authentic nurse", "facing new role and situations that were difficult to handle", "preceptee-centered preceptorship", "healing connection with colleague nurses", and "enhanced status with competence". Conclusion: The findings of the study provide deep understanding on hospital nurses' positive as well as negative experiences of being a preceptor and should inform the development of a more integrative preceptorship program to empower both preceptees and preceptors.

• Speech Sciences
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• v.10 no.1
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• pp.59-67
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• 2003

The purpose of this study was to investigate Korean native speakers' perception of English sounds according to groupings of phonetic contrasts. The four groupings looked at were vowels, voicing (voiced-unvoiced), fricatives with difference in place of articulation, and other clusters of specific sound contrasts, such as stop-fricatives and liquids. The position of a sound in syllable was also examined. According to the results of ANOVA and a post-hoc analysis, the perception of vowels, in the medial position was different from that of consonants in the initial and final position. Vowels proved to be the most difficult group to perceive correctly. With the consonants, there was not a big difference whether the contrasts came initially or finally. The order of difficulty was liquids, fricatives, stop-fricatives, and finally voicing.

• Advances in nano research
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• v.1 no.3
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• pp.125-131
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• 2013

This study is aimed to calculate the radiative lifetime of Wannier-Mott excitons in nanoclusters of a narrow-bandgap semiconductor embedded in a wide-bandgap one. The nanocluster linear dimensions are assumed to be much larger than the radius of the exciton so that the latter is not destructed by the confinement potential as it takes place in small quantum dots. The calculations were carried out for an example of InAs nanoclusters put into the GaAs matrix. It is shown that the radiative lifetime of Wannier-Mott excitons in such clusters increases with the decrease of the cluster dimensions, this tendency being more pronounced at low temperatures. So, the creation of excitons in nanoclusters of a narrow-bandgap material embedded in a wide-bandgap one can be used to significantly prolong their radiative lifetime in comparison with that of excitons in a bulk semiconductor.

• Journal of KIISE:Information Networking
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• v.36 no.3
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• pp.212-221
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• 2009

This paper proposes a novel centralized clustering algorithm, "RLCA : Relative Location based Clustering Algorithm for Wireless Sensor Networks," for constructing geographically well-distributed clusters in general WSNs. RLCA does not use GPS and controls selection-rate of cluster-head based on distances between sensors and BS. We empirically show that RLCA's energy efficiency is higher than LEACH's.

• Biomolecules & Therapeutics
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• v.27 no.2
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• pp.127-133
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• 2019

The study of the genus Streptomyces is of particular interest because it produces a wide array of clinically important bioactive molecules. The genomic sequencing of many Streptomyces species has revealed unusually large numbers of cytochrome P450 genes, which are involved in the biosynthesis of secondary metabolites. Many macrolide biosynthetic pathways are catalyzed by a series of enzymes in gene clusters including polyketide and non-ribosomal peptide synthesis. In general, Streptomyces P450 enzymes accelerate the final, post-polyketide synthesis steps to enhance the structural architecture of macrolide chemistry. In this review, we discuss the major Streptomyces P450 enzymes research focused on the biosynthetic processing of macrolide therapeutic agents, with an emphasis on their biochemical mechanisms and structural insights.

• Development and Reproduction
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• v.23 no.1
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• pp.1-9
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• 2019

The ability of oocytes to undergo normal fertilization and embryo development is acquired during oocyte maturation which is transition from the germinal vesicle stage (GV), germinal vesicle breakdown (GVBD) to metaphase of meiosis II (MII). Part of this process includes redistribution of inositol 1, 4, 5-triphosphate receptor (IP3R), a predominant $Ca^{2+}$ channel on the endoplasmic reticulum membrane. Type 1 IP3R (IP3R1) is expressed in mouse oocytes dominantly. At GV stage, IP3R1 are arranged as a network throughout the cytoplasm with minute accumulation around the nucleus. At MII stage, IP3R1 diffuses to the entire cytoplasm in a more reticular manner, and obvious clusters of IP3R1 are observed at the cortex of the egg. This structural reorganization provides acquisition of $[Ca^{2+}]_i$ oscillatory activity during fertilization. In this review, general properties of IP3R1 in somatic cells and mammalian oocyte are introduced.

• The Pure and Applied Mathematics
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• v.29 no.1
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• pp.59-68
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• 2022

For a finite group G ⊂ GL(n, ℂ), the G-Hilbert scheme is a fine moduli space of G-clusters, which are 0-dimensional G-invariant subschemes Z with H⁰(𝒪_Z ) isomorphic to ℂ[G]. In many cases, the G-Hilbert scheme provides a good resolution of the quotient singularity ℂⁿ/G, but in general it can be very singular. In this note, we prove that for a cyclic group A ⊂ GL(n, ℂ) of type ${\frac{1}{r}}$(1, …, 1, a) with r coprime to a, A-Hilbert Scheme is smooth and irreducible.

• Communications for Statistical Applications and Methods
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• v.31 no.1
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• pp.55-64
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• 2024

In this study, we consider the sample size determination problem for clustered count data with many zeros. In general, zero-inflated Poisson and binomial models are commonly used for zero-inflated data; however, in real data the assumptions that should be satisfied when using each model might be violated. We calculate the required sample size based on a discrete Weibull regression model that can handle both underdispersed and overdispersed data types. We use the Monte Carlo simulation to compute the required sample size. With our proposed method, a unified model with a low failure risk can be used to cope with the dispersed data type and handle data with many zeros, which appear in groups or clusters sharing a common variation source. A simulation study shows that our proposed method provides accurate results, revealing that the sample size is affected by the distribution skewness, covariance structure of covariates, and amount of zeros. We apply our method to the pancreas disorder length of the stay data collected from Western Australia.

• Journal of Practical Engineering Education
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• v.11 no.2
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• pp.259-268
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• 2019

The purpose of the study was to examine the vocational educational system of Egypt, focusing on the effectiveness of the three consecutive cycle-based curriculum and integrated technical education clusters (ITECs) in order to suggest some implications for innovating the current vocational education system of Korea. The vocational education system of Egypt is similar to that of Korea, in terms of general education to go to university and vocational education to go to labor market. However, the Egyptian system is different from the system of Korea in light of the three consecutive cycle-based curriculum that links secondary vocational education, vocational education of college level, and advanced technical and vocational education. In addition, the Egyptian system has adopted the "cluster" approach which integrates technical secondary school, intermediate technical college, and advanced technical college around one physical area so as to promote vocational education in collaboration with regional industries and to guarantee education quality. In the last part, some potential implications were suggested for upgrading the quality of vocational education of Korea based upon the benchmark results of the Egyptian vocational education system and career development of students.