• Korean Journal of Child Studies
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• v.36 no.2
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• pp.75-94
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• 2015

The main purpose of this study was to examine the various aspects of logico-mathematical thinking and its development by observing a block building activity undertaken by infants and toddlers. The subjects comprised 73 young children from between the ages of 12- to 41-months-old. The interviewee was individually asked to build "something tall", making use of 20 blocks. The results of this study were, first, a regular increase by age is seen in congruence, the vertical use of flat blocks, and innovative ways of using triangular blocks. Second, many types of logico-mathematical thinking processes, such as classification, seriation, spatial relationship and temporal relationship, were shown during the block building activities on the part of the 12- to 41-months-olds who took part in this study.

• Journal of the Korean housing association
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• v.23 no.1
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• pp.89-96
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• 2012

The purpose of this study is to find out the characteristics of activity areas according to the age difference and provide the alternatives for space planning of activity areas in classroom of childcare centers. This study used the content analysis method for field survey data collected from 36 classrooms of 9 childcare centers in the Daejeon area. Floor plans were converted to Autocad drawings to analyze the characteristics of activity areas. The results of this study were as follows; 1) In case of 0 to 2-year-old classrooms, they had 6 activity areas such as gross-motor area, role play, block building, language, creative expression, exploration/manipulation area. The activity area with the most low frequency was gross-motor area. 2) In case of 0 to 2-year-old classrooms, the size of activity area was in order of gross-motor area > role play > block building > language > creative expression > exploration/manipulation area. In case of 3 to 5-year-old classrooms, the size of activity area was in order of language > art > role play > math > block building > science > tone and rhythmic area. 3) The central areas with easy access in 0 to 2-year-old classrooms were Large-motor and Imaginary Play Areas. Also, more isolated areas were Manupulatives and Block Areas. The central areas with easy access in 3 to 5-year-old classrooms were Arts, Numbers and Manupulatives. While more isolated areas were Music, Movement and Science Areas.

• Journal of the Korean housing association
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• v.25 no.4
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• pp.83-91
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• 2014

The purpose of this study is to clarify the characteristics between the type of daily routine and spatial configuration of activity areas in classroom and provide alternatives for space planning of activity areas in classroom of child-care centers. This study used the content analysis on daily activity plan and floor plans through field survey. Analysis on floor plans was conducted for 35 classrooms in 9 child-care centers which allowed field survey. The results of this study were as follows; There was no significant difference for classroom size according to the type of daily routine in 3 to 5-year-old classrooms. The average size of classrooms was $61.6m^2$ for care oriented type, $41.4m^2$ for indoor activity oriented type and $48.8m^2$ for group activity oriented type. There was no significant difference in composition of activity areas in classrooms according to the type of daily routine. In case of 0 to 2-year-old classrooms, they were composed of 6 activity areas including gross-motor, role play, block building, language, creative expression, exploration/manipulation. Activity area of the most low frequency was gross-motor area. In case of 3 to 5-year-old classrooms, most classrooms were composed of all the 7 activity areas including art, tone and rhythmic, block building, role play, language, math and science. Most accessible and central areas in 0 to 2-year-old classrooms were gross-motor and role play. Also, most separate areas were exploration/manipulation and block building. Most accessible and central areas in 3 to 5-year-old classroom were art and math. Also, most separate areas were tone and rhythmic and science.

• Korean Management Science Review
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• v.14 no.1
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• pp.67-76
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• 1997

The most research on facility layout problems ignored the actual shapes of activity spaces and the aisles between activities. In many cases, the research also ignored the actual shape of building where the activities are to be arranged. In this paper, We present a block based layout technique that applies a genetic algorithm to search for a very good facility layout with horizontal aisles. From the extensive experiments for two different cases with respect to the shape of activity space, it was found that the proposed method generated better layouts than the ones obtained by applying Tam's algorithm in all test problems. The proposed algorithm showed about 10% improvement of performance on the average. We determined the best combination of the reproduction rule and the genetic operators with their probabilities for each test problem through the experiment.

• Journal of Radiation Industry
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• v.10 no.4
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• pp.181-187
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• 2016

Selective ${\beta}_1$-agonist and antagonists are used for the treatment of cardiac diseases including congestive heart failure, angina pectoris and arrhythmia. Selective ${\beta}_1$-antagonists including nebivolol have high binding affinity on ${\beta}_1$-adrenergic receptor, not ${\beta}_2$-receptor mainly expressed in smooth muscle. Nebivolol is one of most selective ${\beta}_1$-blockers in clinically used ${\beta}_1$-blockers including atenolol and bisoprolol. We tried to develop clinically useful cardiac PET tracers using a selective ${\beta}_1$-blocker. Nebivolol is $C_2$-symmetric and has two chromane moiety with a secondary amino alcohol and aromatic fluorine. We adopted the general synthetic strategy using epoxide ring opening reaction. Unlike formal synthesis of nebivolol, we prepared two chromane building blocks with fluorine and iodine which was transformed to diaryliodonium salt for labelling of $^{18}F$. Two epoxide building blocks were readily prepared from commercially available chromene carboxylic acids (1, 8). Then, the amino alcohol building block (15) was prepared by ammonolysis of epoxide (14) followed by coupling reaction with the other building block, epoxide (7). Diaryliodonium salt, a precursor for $^{18}F$-aromatic substitution, was synthesized in moderate yield which was readily subjected to $^{18}F$-aromatic substitution to give $^{18}F$-labelled nebivolol.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.57.2-57.2
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• 2021

An asteroid is important for understanding the condition of our solar system in early-stage because an asteroid, considered as a building block of the solar system, preserves the information when our solar system was formed. It has been continuously flowing into the near-Earth space, and then some asteroids have a probability of impacting Earth. Some asteroids have valuable minerals and volatiles for future resources in space activity. Korean government clarified, in the 3rd promotion plan for space activity, an asteroid sample return mission by the mid-2030s. However, it is almost impossible to do so based on only a single experience of an exploration mission to the Moon, Korea Pathfinder Lunar Orbiter, which will be launched in mid-2022. We propose a Rendezvous Mission to Apophis(RMA), beneficial in terms of science, impact hazardous, resource, and technical readiness for the space exploration of Korea.

• IE interfaces
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• v.20 no.3
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• pp.395-406
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• 2007

In the telecommunication industry, estimation of the cost of network facilities is very important since depreciation cost of the facilities accounts for a large portion of the product cost. Moreover, cost estimation in the industry becomes more difficult because of increasing indirect cost upon digital convergence, expanding multi-purpose facilities, complexity of service product, etc. Nevertheless, not much seem to have been done in improving estimation methodology of the cost of network facilities. As a result, the quality of cost information on network facilities has deteriorated, and now even decision-makers in the industry dismiss the information. Recently, two major telecommunication companies adopted a new network cost estimation method to deal with the issue. In this paper, we study the concept of new cost estimation method and the procedure to develop and apply it. We also suggest the method to carry out the cost allocation using Matlab which is more efficient and time-saving than other commercial cost calculation packages.

• Korean Journal of Materials Research
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• v.22 no.10
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• pp.504-507
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• 2012

Synthesis of RGO (reduced graphene oxide)-CdS composite material was performed through CBD (chemical bath deposition) method in which graphene oxide served as the support and Cadmium Sulfate Hydrate as the starting material. Graphene-based semiconductor photocatalysts have attracted extensive attention due to their usefulness for environmental and energy applications. The band gap (2.4 eV) of CdS corresponds well with the spectrum of sunlight because the crystalline phase, size, morphology, specic surface area and defects, etc., of CdS can affect its photocatalytic activity. The specific surface structure (morphology) of the photocatalyst can be effective for the suppression of recombination between photogenerated electrons and holes. Graphene (GN) has unique properties such as a high value of Young's modulus, large theoretical specific surface area, excellent thermal conductivity, high mobility of charge carriers, and good optical transmittance. These excellent properties make GN an ideal building block in nanocomposites. It can act as an excellent electron-acceptor/transport material. Therefore, the morphology, structural characterization and crystal structure were observed using various analytical tools, such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. From this analysis, it is shown that CdS particles were well dispersed uniformly in the RGO sheet. Furthermore, the photocatalytic property of the resulting RGO-CdS composite is also discussed in relation to environmental applications such as the photocatalytic degradation of pollutants. It was found that the prepared RGO-CdS nanocomposites exhibited enhanced photocatalytic activity as compared with that of CdS nanoparticles. Therefore, better efficiency of photodegradation was found for water purification applications using RGO-CdS composite.

• Journal of Microbiology and Biotechnology
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• v.20 no.9
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• pp.1300-1306
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• 2010

Ethyl (R, S)-4-chloro-3-hydroxybutanoate (ECHB) is a useful chiral building block for the synthesis of L-carnitine and hypercholesterolemia drugs. The yeast reductase, YOL151W (GenBank locus tag), exhibits an enantioselective reduction activity, converting ethyl-4-chlorooxobutanoate (ECOB) exclusively into (R)-ECHB. YOL151W was generated in Escherichia coli cells and purified via Ni-NTA and desalting column chromatography. It evidenced an optimum temperature of $45^{\circ}C$ and an optimum pH of 6.5-7.5. Bacillus subtilis glucose dehydrogenase (GDH) was also expressed in Escherichia coli, and was used for the recycling of NADPH, required for the reduction reaction. Thereafter, Escherichia coli cells co-expressing YOL151W and GDH were constructed. After permeablization treatment, the Escherichia coli whole cells were utilized for ECHB synthesis. Through the use of this system, the 30 mM ECOB substrate could be converted to (R)-ECHB.

• BMB Reports
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• v.52 no.3
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• pp.163-164
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• 2019

The ribosomal synthesis of proteins in the eukaryotic cytosol has always been thought to start from the unformylated N-terminal (Nt) methionine (Met). In contrast, in virtually all nascent proteins in bacteria and eukaryotic organelles, such as mitochondria and chloroplasts, Nt-formyl-methionine (fMet) is the first building block of ribosomal synthesis. Through extensive approaches, including mass spectrometric analyses of the N-termini of proteins and molecular genetic techniques with an affinity-purified antibody for Nt-formylation, we investigated whether Nt-formylated proteins could also be produced and have their own metabolic fate in the cytosol of a eukaryote, such as yeast Saccharomyces cerevisiae. We discovered that Nt-formylated proteins could be generated in the cytosol by yeast mitochondrial formyltransferase (Fmt1). These Nt-formylated proteins were massively upregulated in the stationary phase or upon starvation for specific amino acids and were crucial for the adaptation to specific stresses. The stress-activated kinase Gcn2 was strictly required for the upregulation of Nt-formylated proteins by regulating the activity of Fmt1 and its retention in the cytosol. We also found that the Nt-fMet residues of Nt-formylated proteins could be distinct N-terminal degradation signals, termed fMet/N-degrons, and that Psh1 E3 ubiquitin ligase mediated the selective destruction of Nt-formylated proteins as the recognition component of a novel eukaryotic fMet/N-end rule pathway, termed fMet/N-recognin.