• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.4B no.4
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• pp.206-210
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• 2004

This paper deals with a parameter estimation of the DC-DC converter system for its diagnosis. Especially, we present the results of parameter estimation for the DC-DC converter model by the system identification method. The parameter estimation for the DC-DC converter system aims at the diagnosis of its operating status. For the operating status diagnosis of the DC-DC converter system, we assume that the DC-DC converter system is an equivalent model of the Buck converter and estimate the main parameter for on-line diagnosis. In addition, for verification of an estimated parameter, we compare a bode plot of the estimated system transfer function and measurement results of the HP4194 instrument. It is a control system analyzer for system transfer function measurement. Our results confirm that the main parameter for diagnosis of the DC-DC converter system can be estimated by the system identification method and that the aging status of the system can be predicted by these results on operating status.

• International Journal of Contents
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• v.6 no.3
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• pp.10-14
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• 2010

Researchers in Korea and elsewhere have carried out a wide variety of important research activities in their respective fields, producing valuable research results. For such diverse research results to be shared and exchanged among researchers working in the same discipline and research subject there needs to be a community environment based on free utilization of information. Against this backdrop, this study seeks to classify and reprocess the reference/factual content owned by the KISTI (Korea Institute of Science and Technology Information), a state-run distributor of information on science and technology, by the different research subjects. It also seeks to develop and provide a community model based on the concepts of open archiving and open access for the researchers specialized in the related fields of research. This community model is developed focusing on the research results from the field of bioscience, where the most extensive studies are currently being conducted. To develop the community model, this study: (a) surveys the current status of the content owned by KISTI; (b) analyzes the patterns and characteristics of biological scientific content among the KISTI-owned content; and (c) designs a web platform where researchers can freely upload/download research results.

• Structural Engineering and Mechanics
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• v.90 no.5
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• pp.493-504
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• 2024

This paper presents the methodology and results for the investigation of the structural safety of 40 aged underground water tanks to support the weight of photovoltaic (PV) systems that were supposed to be placed on their roof reinforced concrete (RC) slabs. The investigation procedure included (1) review of available documents; (2) visual inspection of the roof RC slabs; (3) carrying out a series of nondestructive (ND) tests; and (4) analysis of results. Out of the 40 tanks, eleven failed the visual inspection phase and were discarded from further investigation. The roof RC slabs of the tanks that passed the visual inspection were subjected to a series of ND tests that included infrared thermography, impact echo, ultrasonic pulse velocity (UPV), Schmidt hammer, concrete core compressive strength, and water-soluble chloride content. The NDT results proved that eight more tanks were not suitable to support the PV systems. Based on the results of the visual inspection and testing, a probabilistic decision-making criterion was established to reach a decision regarding the structural integrity of the roof slabs. The study concluded that the condition of the drainage filter was essential in protecting the tanks and its intact presence can be used as a strong indication of the structural integrity of the roof RC slabs.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.22 no.4
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• pp.442-451
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• 2015

Purpose: The purpose of this study was to analyze reports of qualitative research published in Journal of Korean Academy of Fundamentals of Nursing (JKAFN). Methods: Twenty four qualitative research studies using in-depth interviews and focus group interviews published in JKAFN from 1994 to 2014 were selected for analysis. Chosen reports were analyzed by consolidated criteria for reporting qualitative research (COREQ), which is a reporting guideline for qualitative research. COREQ consists of 32 items and 3 domains. Results: In the 1st domain, the relationship of researchers and research participants, bias and understanding of the researchers on the study phenomenon were analyzed less than other items. In the 2nd domain, methodological research was carried out across various qualitative studies, but the description of the research environment and research questions for the interview guidelines was insufficient. In the 3rd domain, research results and data were consistent, but data showing opposing content and explanations of negative practices were not done at all. Conclusion: These results indicate a need for the development of evaluation tools for qualitative research and items should be added to improve the reliability and validity, research should be related to the ethics in the framework of the COREQ.

• Research in Mathematical Education
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• v.26 no.2
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• pp.63-82
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• 2023

In the context of Korean educational research, the number of qualitative research studies has gradually increased since 2000. It has become one of the most important research methods today. The field of math education is no exception to this trend, and qualitative approaches are now becoming one of the main research methods. This increase in qualitative research has contributed to the provision of detailed information about educational practice, but at the same time, the overall level of credibility in the results of qualitative research seems to be lower than that of quantitative research. This study started with the problem consciousness that the number of qualitative studies is increasing in the field of mathematical education, but there is a lack of discussion on the methodology of applying qualitative research methods. In this study, among the papers published in the journal related to mathematical education, papers using a qualitative approach are analyzed focusing on cross-case analysis. Based on the analysis results, the tendency to use qualitative approaches is diagnosed, ways of improving the validity and trustworthiness of qualitative research results in the field of mathematical education are examined, and implications and suggestions are presented.

• Ecology and Resilient Infrastructure
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• v.5 no.3
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• pp.156-162
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• 2018

This research aimed at analyzing comparison results between in gravel and sand bed with respect to the detailed Acoustic Doppler Current Profiler (ADCP) measurement in a velocity, depth, and flow rate data based on Acoustic Doppler Velocimeter (ADV) measurement result. Conclusionally, similar results were shown for gravel and sand bed in velocity, depth and flow rate data using ADV and ADCP measurement. The results of the flow rate show a relative error mean of 3.5 - 4.8% in the gravel bed and 0.02 - 3.2% in the sand bed, which is better performance than the mean error of 5% suggested by United States Geological Survey (USGS). The results can be used as a basis data for the measurement of ADCP and potentially able to be utilized for the more detailed uncertainty analysis of ADCP flow rate measurement.

• Korean Journal of Adult Nursing
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• v.15 no.2
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• pp.226-235
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• 2003

Purpose: This study is to analyze the research trends centering on the theses related to CAT released in nursing of Korea. Method: The researcher collected the academic degrees and theses published on the book of the academic society from 1980 to 2001, and examined 88 domestic dissertations on nursing science of the CAT. Result: 1) By department, the results were: the nursing thesis 88(43.3%), medical field 45(22.1%), psychology counseling education 28(14%). 2) In the type of the CAT in nursing, the results were: acupressure 28(31.5%), Dan-Jeon Breathing 14(15.7%), aroma therapy 5(5.6%) in order. 3) The number of theses increased every year after 1997. 4) As for the type of study design, the results were: the experimental research had the most(47), and the survey research(30). 5) As for the subject, the results were: patients with disease(44), healthy adults(29), literature(9) and medical staff were only 6 theses. 6) In the theme of the theses, the results were: the effect of therapy(76), the experience of therapy(26), adaptation of nursing of therapy(11) and literature review were 7. Conclusion: More research needs to be encouraged in the unsatisfactory fields. Researches should be conducted to extend into the practical fields as Korean nursing mediation, project for the establishment of health policies should be conducted.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.9
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• pp.621-629
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• 2020

This research focuses on determining the impact of human resource management activities on the compatibility and work results of employees of Ho Chi Minh Stock Exchange (HOSE) listed companies. The paper includes five parts: introduction, literature review, research methodology, research results, and conclusion and policy implications. The data are collected from the survey of 350 listed companies in HOSE, in which 315 survey notes filled with sufficient information are used for analysis. The paper employs both qualitative method and quantitative method. Group discussion of 10 experts is for qualitative research. Quantitative method performs analysis of Statistics, Cronbach's Alpha, EFA analysis, CFA analysis and SEM model. The results of the research clearly indicate that human resource management (HRM) activities are measured through improving the ability, improving the motivation and improving the opportunity. While compatibility is measured through suitability, connection and sacrifice; whereby HRM activities of ability improvement have a positive effect on the job suitability and connection; HRM activities of motivation improvement have a positive effect on the job suitability, connection and sacrifice; and HRM activities of opportunity improvement have a positive effect on the job suitability, sacrifice and connection; Finally, the job suitability, sacrifice and connection positively affect the work results of employees.

• Journal of Distribution Science
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• v.20 no.2
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• pp.55-64
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• 2022

Purpose: This research is aimed to study the level of the intellectual potential distribution, as well as the correlation between economic growth and key indicators of intellectual potential in each region of Kazakhstan. A review of the conceptual framework shows that there is a large body of research evaluating the level of intellectual potential in different ways based on different factors. Research design, data, and methodology: The research methodology is divided into two groups the integral index method using the normalization of indicators, weighting, and ranking; the method of correlation analysis. By the proposed methodological approaches, were calculated a set of factors affect the distribution of the intellectual potential. Statistics are taken for indicators of development of the intellectual potential for 2011-2020 from the Bureau of National Statistics. Results: Ranking results showed gaps between regions in Kazakhstan by the level of intellectual potential. Correlation analysis results revealed a statistically significant relationship on expenditures on R&D, computer literacy, innovative products, number of PhD students, and cultural and leisure indicators. Conclusions: Based on the obtained results of the intellectual potential level development there were given recommendations for the reproduction and regulation of the intellectual potential in the future.

• International Journal of High-Rise Buildings
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• v.1 no.3
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• pp.221-228
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• 2012

Shanghai Tower is a super high-rise building of 632 m height with 'mega frame-core- outrigger truss' structure system. Due to the complexity and irregularity of structure, shaking table test was carried out to investigate its seismic performance. A 1/40 scaled test model was designed, built and tested on shaking table under earthquake of small, moderate and large levels. The experimental results showed that the structure can meet the requirements of Chinese codes and reach scheduled performance objectives. Elastic and plastic time-history analysis on the structure were carried out and the results were compared to experimental results. Based on the research results some suggestions were proposed to contribute favorable effect on the seismic capacity of the structure.