• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1605-1609
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• 2007

In the case of Linear induction motor(LIM), numerical analysis method like Finite Element Method(FEM) has been mainly used to analyze the travelling magnetic field problem which includes the velocity-induced electromotive force. If the problem including the velocity-induced electromotive force is analyzed by FEM using Galerkin method, the solution can be oscillated according to Peclet Number, which is determined by conductivity, permeability, moving velocity and size of mesh. Consequently, the accuracy of the solution can be low and the Loops of flux can be occurred at the secondary back-iron. These loops of flux occurred at the secondary back-iron does not exist physically, but it can be occurred in the analysis. In this case, the loops of flux can be generally removed by using Up-Wind method which is impossible to apply a conventional S/W tool(Maxwell 2D). Therefore, in this paper, authors examined the Loops of flux occurred at the secondary back-iron of LIM according to variations of Peclet Number, and analyzed whether these loops of flux affect on the thrust force characteristics of LIM or not.

• International Journal of Advanced Culture Technology
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• v.6 no.3
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• pp.211-215
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• 2018

Ventilator-associated pneumonia (VAP) is a lung infection that develops in patients receiving mechanical ventilation. VAP contributes to about 50% of hospital-acquired pneumonia in ICU settings. One of the recommendation of the Institute of for Healthcare Improvement ventilator bundle is HOB elevation. HOB elevation affects shearing forces and makes higher risk for pressure injury development. Pressure injury (PI) is localized damage to the skin over a bony prominence. PI prevention guidelines recommend that HOB positioning should be lower to reduce risk for PI development which contradicts VAP prevention guidelines for the HOB between 30 and 45 degrees for ICU patients. This presents a care dilemma and tension. The purpose of this study was to perform a secondary data analysis using cumulative electronic health record data in order to determine the association of HOB elevation with VAP and PI in ICU patients. A secondary data analysis was conducted to determine whether HOB elevation is associated with VAP and PI. HOB elevation was not likely to be associated with VAP prevention whereas it was likely to be related to PI development. This is somewhat contrary to popular data and publications. Prospective cohort study is desired to inform us in an evidence-based fashion what actually is optimal HOB elevation for ventilated patients in ICU settings.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.10
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• pp.548-554
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• 2013

A thermodynamic analysis of the R404A refrigeration system with an internal heat exchanger using R744 as a secondary refrigerant is presented in this paper to optimize the design for operating parameters of the system. The main results are summarized as follows: The COP increases with increasing subcooling and superheating degree of R404A, internal heat exchanger and compression efficiency of the R404A cycle and evaporating temperature of the R744 cycle and decreasing temperature difference of the cascade heat exchanger and condensing temperature of the R404A cycle. The mass flow ratio decreases with increasing evaporating temperature of the R744 cycle and internal heat exchanger efficiency of the R404A cycle and decreasing subcooling and superheating degree of the R744 cycle, temperature difference of the cascade heat exchanger and condensing temperature of the R404A cycle.

• Journal of Astronomy and Space Sciences
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• v.35 no.4
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• pp.219-225
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• 2018

Cosmic rays are ions that move at relativistic speeds. They generate secondary cosmic rays by successive collisions with atmospheric particles, and then, the secondary particles reach the ground. The secondary particles are mainly neutrons and muons, and the neutrons are observed by the ground neutron monitor. This study compared the diurnal variation in cosmic ray intensity obtained via harmonic analysis and that obtained through the pile-up method, which was examined in a previous study. In addition, we analyzed the maximum phase of the diurnal variation using four neutron monitors with a cutoff rigidity below approximately 6 GV, located at similar longitudes to the Oulu and Rome neutron monitors. Expanding the data of solar cycles 20-24, we examined the time of the maximum cosmic ray intensity, that is, the maximum phase regarding the solar cyclic modulation. During solar cycles 20-24, the maximum phase derived by harmonic analysis showed no significant difference with that derived by the pile-up method. Thus, the pile-up method, a relatively straightforward process to analyze diurnal variation, could replace the complex harmonic analysis. In addition, the maximum phase at six neutron monitors shows the 22-year cyclic variation very clearly. The maximum phase tends to appear earlier and increase the width of the variation in solar cycles as the cutoff rigidity increases.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.338-344
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• 2023

Curcuma longa is a plant belonging to the genus Curcuma and is distributed across various Asian regions. This plant is widely known for its rhizomes, which possess a variety of pharmacological properties. However, although the leaves and stems of this plant also contain several health-promoting secondary metabolites, very few studies have characterized these compounds. Therefore, our study sought to quantify the secondary metabolites from the leaves and stems of Curcuma longa L. (LSCL) using liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) and high-performance liquid chromatography (HPLC). Our LC-ESI-MS analyses detected twenty-one phenolic compounds in the LSCL, among which fifteen compounds were detected via HPLC analysis. Four compounds, namely vanillic acid (0.129 mg/g), p-coumaric acid (0.431 mg/g), 4-methylcatechol (0.199 mg/g), and afzelin (0.074 mg/g) were then quantified. These findings suggest that LSCL is rich in secondary metabolites and holds potential as a valuable resource for the development of functional and nutritional supplements in the future.

• Journal of Music and Human Behavior
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• v.15 no.1
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• pp.1-23
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• 2018

Recently, there has been a growing focus on the concerns pre-service teachers have as they move through different stages of their teacher preparation programs. Accordingly, the purpose of this study was to investigate pre-service secondary music teachers' concerns about music teaching and learning. The specific research questions were as follows: (a) What concerns are most common among participants? (b) What are differences in the concerns of pre-service secondary music teachers based on their stage of teacher preparation? (c) What are differences in the concerns of pre-service secondary music teachers based on their previous teaching experiences? A survey was distributed to pre-service secondary music teachers in a university in Seoul, and responses from a total of 93 participants were included in the final analysis. Data analysis indicated that pre-service music teachers experienced more concerns related to teaching tasks and student impact than themselves. Also, as participants progressed through their teacher preparation programs, self concerns decreased while task concerns and student impact concerns increased. Pre-service secondary music teachers who had previously taught in a school had fewer concerns than participants with no teaching experience. Suggestions for how teacher preparation programs can address the concerns of pre-service secondary music teachers are offered.

• Applied Chemistry for Engineering
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• v.26 no.3
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• pp.287-293
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• 2015

This paper discusses quantitative analyses of patents published for cathode active materials for lithium secondary batteries based on layer structure. Numbers of the patents analyzed were 356, 1628, 2915, 439, and 611 for Korea, USA, Japan, Europe, and PCT (WO), respectively. Trends of improved technologies and alternative technologies concerning lithium cobalt, from 1991 to 2012 were examined and the patent shares distribution of each principal countries about lithium secondary battery technologies were also scrutinized. The number of patents for the mixed structure technology and next-generation lithium secondary battery technology increased numerously in 2000. Particularly in 2005, lots of patents were also published and SANYO (34.5%), SONY (17.5%), LG (7%), and SAMSUNG (5.5%) possessed leading patent applicants. Finally, the research focus on cathode active materials for lithium secondary batteries was confirmed by bubble chart distributions for component-by-step process.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2005.09a
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• pp.215-220
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• 2005

Generally, enzymes in the starch biosynthesis pathway exist in many isoforms, contributing to the difficulties in the dissection of their specific roles in controlling starch properties. In this study, we present an algorithm as an alternative method to classify isoforms of starch biosynthesis enzymes based on their conserved secondary structures. Analysis of the predicted secondary structure of plant soluble starch synthase I (SSI) and soluble starch synthase II (SSII) demonstrates that these two classes of isoform can be reclassified into three subsets, SS-A, SS-B and SS-C, according to the differences in the secondary structure of the protein at C-terminus. SS-A reveals unique structural features that are conserved only in cereal plants, while those of SS-B are found in all plants and SS-C is restricted to barley. These findings enable us to increase the accuracy in the estimation of evolutionary distance between isoforms of starch synthases. Moreover, it facilitates the elucidation of correlations between the functions of each enzyme isoforms and the properties of starches. Our secondary structure analysis tool can be applicable to study the functions of other plant enzyme isoforms of economical importance.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.5
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• pp.1096-1107
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• 2014

The purpose of this study was to investigate teachers' recognition on field practice and effectiveness of creativity and character education. This study used post tests to examine the effects of teacher training for creativity and character education on 451 teachers. The results were as follows. Firstly, the average in satisfaction of teacher training for creativity and character education was 4.65 for elementary teachers and 4.35 for secondary teachers in summer, and 4.55 for elementary teachers and 4.42 for secondary teachers in winter. Secondly, effectiveness of teacher training on creativity and character education was showed highly as more than 4.0 and was higher in winter than in summer. Thirdly, in the case of field practice and effectiveness of teacher training for creativity and character education, the average of elementary teachers(3,66) was higher in respect of educational environment than that of secondary teachers(3.20) and the averages of elementary teachers and secondary teachers were 3.85 and 3.42 in respect of subject activity, respectively. In practising creativity and character education, it was analyzed that both elementary(ave. 3.89) and secondary(ave. 3.84) teachers went through some difficulties for curriculum reconstruction, development of instructional model, program development, and human and physical supports.

• Journal of The Korean Association of Information Education
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• v.11 no.2
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• pp.157-165
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• 2007

This study aims to compare and analyse computer curriculum and textbooks of South Korea and North Korea in order to provide the basis for unifying the Informatics Education. Result of this study follows : First, there isn't any course for Informatics Education in the elementary school but it was requisitely carried 2 hours per week in secondary school in North Korea. But contents of curriculum is much different according to the level of school : genius secondary school, first secondary school, general secondary schol. In especially, Informatics Education had centered in genius secondary school. Second, in comparison of computer textbooks used in South and North Korea, we found that most contents of South Korea textbook was selected equally from all scope whereas those in North Korea were not contained the newest contents(e.g. Internet, Multimedia). But in contrast to South Korea textbook, there was BASIC programing course for improving problem-solving skills in North Korea textbook.