• The Transactions of the Korean Institute of Power Electronics
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• v.21 no.1
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• pp.42-48
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• 2016

Light-emitting diode (LED) drivers are recently replacing fluorescent lamps; these drivers can operate adaptively with various ballasts without modifying and removing such ballasts. To satisfy these trends, a LED driver that is compatible with both electronic and magnetic ballasts is proposed in this study. Unlike conventional LED drivers, the proposed driver has a ballast recognition circuit and a mode selection circuit to operate ballasts at optimal conditions. Therefore, it features low voltage stress, high efficiency, and good compatibility with both electronic and magnetic ballasts. Moreover, it can be compatible with a wide selection of ballasts from various manufacturers. To confirm the validity of the proposed LED driver, results of the theoretical analysis and experimental verification performed on a 15 W-rated prototype are presented.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2005.05a
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• pp.342-348
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• 2005

This study was carried out fusion-welded butt joints in SWS 490A high strength steel subjected to tensile test that load-deflection curve. The windowed or short-time Fourier transform (WFT or SIFT) makes possible for the analysis of non-stationary or transient signals into a joint time-frequency domain and the wavelet transform (WT) is used to decompose the acoustic emission (AE) signal into various discrete series of sequences over different frequency bands. In this paper, for acoustic emission signal analysis to use a continuous wavelet transform, in which the Gabor wavelet base on a Gaussian window function is applied to the time-frequency domain. A wavelet transform is demonstrated and the plots are very powerful in the recognition of the acoustic emission features. As a result, the technique of acoustic emission is ideally suited to study variables which control time and stress dependent fracture or damage process in metallic materials.

• Korean Journal of Occupational Health Nursing
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• v.24 no.2
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• pp.76-85
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• 2015

Purpose: The purpose of this study was to identify knowledge structure of the Korean Journal of Occupational Health Nursing from 1991 to 2014. Methods: 400 articles between 1991 and 2014 were collected. 1,369 keywords as noun phrases were extracted from articles and standardized for analysis. Co-occurrence matrix was generated via a cosine similarity measure, then the network was analyzed and visualized using PFNet. Also NodeXL was applied to visualize intellectual interchanges among keywords. Results: According to the results of the content analysis and the cluster analysis of author keywords from the Korean Journal of Occupational Health Nursing articles, 7 most important research topics of the journal were 'Workers & Work-related Health Problem', 'Recognition & Preventive Health Behaviors', 'Health Promotion & Quality of Life', 'Occupational Health Nursing & Management', 'Clinical Nursing Environment', 'Caregivers and Social Support', and 'Job Satisfaction, Stress & Performance'. Newly emerging topics for 4-year period units were observed as research trends. Conclusion: Through this study, the knowledge structure of the Korean Journal of Occupational Health Nursing was identified. The network analysis of this study will be useful for identifying the knowledge structure as well as finding general view and current research trends. Furthermore, The results of this study could be utilized to seek the research direction in the Korean Journal of Occupational Health Nursing.

• Journal of Korean Biological Nursing Science
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• v.14 no.3
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• pp.166-173
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• 2012

Purpose: This study was designed to find differences between physical activity and health-related factors of Korean male adults. Methods: Using the 2010 Korean National Health and Nutrition Examination Survey (NHANES V-1), the data of 1,876 Korean males over 30 years old who completed the Health Interview, Health Behavior Surveys and International Physical Activity Questionnaire (IPAQ) were analyzed. Analysis of differences in physical activity according to socio-demographic factors, physical health-related factors and psychological health-related factors was tested using the F-test and chi-square test with SPSS 12.0. Results: The high physical activity group was merely 2.5% and the moderate group was 51.4%. In each group, the study showed significant differences in age (p=.017), education status (p=.019), and economic status (p=.032) of socio-demographic factors, in body mass index (p=.003), vitamin D (p=.020) and hypertension status (p=.007) of physical health-related factors, and in recognition of stress (p=.027) of psychological health-related factors. Conclusion: These results revealed that physical activity can play an important role in nursing intervention of physical and psychological health-related factors in male adults.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.4
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• pp.693-700
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• 2002

Recently, the mechanical structures applied to many industrial products, especially in electronic products, appear to be miniaturized and complicated. This trend makes it difficult to analyze the stress distribution of those mechanical structures and generates new challenges for precise measurement of strain. In order to solve this measurement problem many optical measurement techniques have been suggested. Among those, the ESPI(Electronic Speckle Pattern Interferometry) has been considered as one of the most useful tools. But the shortage of recognition and difficulties of measurement have limited its industrial applications in spite of its excellent capabilities. Therefore in this study, not only the verification of the FEA result but the enhancement of industrial application of ESPI was tried by measuring the in-plane displacement of mechanical structure with ESPI, which is difficult to be measured with strain gauge.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.25 no.3
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• pp.185-196
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• 2018

Purpose: The purpose of this study was to investigate the alopecia experience in adults and to explain the process of their experiences. Methods: Using a grounded theory methodology, 18 interviews were performed with fourteen men and four women, 34~57 years of age, suffering from alopecia. Data were analyzed using the constant comparative analysis method. Results: The core category emerged as "inescapable fetters". adults with alopecia engaged in three stages: embarrassment, seeking solution, and acceptance phase. Causal conditions were a vicious cycle of stress, biological factors and poor life style. Contextual conditions were recognition of irreversibleness, negative social awareness, and marriage. The central phenomenon of the adaptation process among the adults with alopecia was withdrawn life due to negative body image. Action/Interaction strategies included rely on medical treatment, efforts to take good care of hair, research for information treatment, efforts to cover up hair loss, and mind control. Intervening conditions were time cost, economic cost, support of surrounding people. Consequences was burden of unfinished lifetime homework. Conclusion: When caring for these adults, it is important to identify needs, allow patients to express what they want at that moment and support them in maintaining a daily life.

• Journal of fish pathology
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• v.34 no.2
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• pp.243-248
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• 2021

Offshore wind power generation is an energy generation field that is rapidly developing owing to the increasing demand for clean energy. However, the physiological response of fish to the underwater noise generated during construction or operation of wind turbines is unclear. We confirmed the effects of sound pressures of 125, 135, 145, and 155 dB/µPa, including 140 dB/µPa (the standard sound pressure for noise damage recognition in South Korea), through serum analysis in rock bream (Oplegnathus fasciatus). High mortality induced by reduced immunity through artificial infection after stimulation was confirmed. These results suggest that rock bream is negatively affected by the noise generated during the construction of offshore wind power plants.

• Journal of The Korean Society of Integrative Medicine
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• v.7 no.1
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• pp.57-64
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• 2019

Purpose : This study was implemented to identify the risk conditions influencing suicidal ideation in a nationally representative sample of elderly South Koreans. Methods : Data from 1,152 men and 1,581 women aged 65 years or older were gathered from the 2013 and 2014 Korea National Health and Nutrition Examination Survey VI. All analyses were performed using SPSS. To determine significant correlations between risk condition and suicidal ideation, a t-test was used. Results : There were differences in suicidal ideation according to the following individual factors: age, educational background, marital status, economic activity, recognition of stress, experience of depression, and economic status. There were differences in suicidal ideation according to the following health-related factors: subjective health status, EQ-5D (EuroQoL-5 Dimensions), hours of sleep, and BMI. There were also differences in suicidal ideation according to the following disease-related factors: HTN, COPD, asthma, stroke, depression and osteoarthritis. Conclusion : The findings indicate that broad intervention programs should be distributed to prevent suicidal ideation. It is also recommended that programs be developed in a way that can help manage the variables identified in this study. Furthermore, follow-up studies should be conducted to verify the program.

• The Journal of Korean Society for School & Community Health Education
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• v.20 no.2
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• pp.25-36
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• 2019

Purpose: The purpose of this study was to examine the factors affecting of health screening among persons with disabilities. Method: The study examines the factors affecting of health screening using over 20 years of age who participated in the 2017 National survey of the disabled data. Subjects were 6,332 person with disabilities over 20 years of age. Data were analyzed using descriptive statistics, X2-test, multiple logistic regression with the SPSS win 21.0 program. Results: Health screening among persons with disabilities is differentiated with education level, marital status, Subjective House economic status, Health insurance, Economic activity, Type of disability, Grade of disability, Stress recognition, Depressive symptom, Suicidal thinking, Suicidal attempt, and grade of disability. The significant predictors of the health screening were age, Subjective House economic status, Economic activity, and Grade of disability. Conclusion: We should consider age, disability level, and economic level when developing a screening program for people with disabilities. Especially, the development and promotion of the health screening program for persons with disabilities and related education are required.

• 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.