• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.2
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• pp.157-162
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• 2023

Among the failures of photovoltaic power generation facilities, failures caused by surges account for 20% of the total failure rate, and energy emissions of tens to hundreds [A] during power generation and electrical damage to inverters and connection boards lead to electrical safety accidents. In particular, in the case of lightning, an abnormal voltage is induced in an electric circuit to destroy insulation, and the current flowing at this time causes a fire and acts as a factor that accelerates the deterioration of parts. Due to this action, the problem of electrical safety of solar power generation devices spreading from outside the city center to the inside of the city center such as houses, apartments, and government offices is emerging. Since lightning strikes cause both field-based and conducted electrical interference, this effect increases with increasing cable length or conductor loops. In addition, surge damages not only solar modules, inverters and monitoring devices, but also building facilities, which can eventually cause operational shutdown due to fire of the photovoltaic power generation system and consequent financial loss. Therefore, in this paper, a lightning protection system for solar power generation devices is studied for the purpose of reducing property damage and human casualties due to the increase in fire and electrical safety accidents caused by lightning strikes in photovoltaic power generation systems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3263-3274
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• 2013

This study purposed to examine the relationship between personal goals and perceptions of calling. For the purpose, this study conducted a questionnaire survey of 371 workers(finance, educational service, IT service sector) in Metropolitan area. Data were analyzed by t-test, Pearson's correlation, correlation analysis. The results were as follows. The individuality of personal goals and presence-transcendent summons and purpose & meaning, prosocial orientation of perceptions of calling were significantly different according to school career and the social responsibility, resource provision of personal goals and all sub-factors concerning perceptions of calling according to religion existence. Also, the individuality of personal goals and all sub-factors concerning perceptions of calling were significantly different according to organization type and according to their job, the presence-transcendent summons and purpose & meaning, prosocial orientation of perceptions of calling were significantly different. According to groups which have high or low integrative social relationship goals, perceptions of calling were significantly different. There was a correlation between the integrative social relationship goals and the perceptions of calling. Therefore, in order to encourage workers' perceptions of calling, the importance of integrative social relationship goals were verified. And it is necessary to have supporting systems to let workers design their life goals through their job in their organization.

• Korean Journal of Psychosomatic Medicine
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• v.23 no.2
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• pp.114-120
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• 2015

Objectives : This study aimed to investigate the risk factors of depression for patients with tuberculosis(TB). Methods : A total of 57 patients with TB were recruited. All participants completed the Becks Depression Inventory-II for evaluating depressive symptoms. The risk factor for depression was analyzed by binary logistic regression analysis. Nomogram was performed for probability of depression. Results : Low body mass index(BMI, OR 0.801, 95% CI 0.65, 0.98), interruption of treatment for TB(OR 5.908, 95% CI 1.19, 29.41), past history of depression(OR 24.653, 95% CI 1.99, 308.44) were associated with increased risk for depression. The calibration curve for predicting probability of survival showed a good agreement between the nomogram and actual observation(Original C-index=0.789, bias corrected C-index=0.754). Conclusions : The result of the present study indicate that low BMI, interruption of treatment for TB, and past history of depression were risk factors for depression in patients with TB. The psychiatric intervention may be needed to prevent depression if the patients with TB have risk factor during treatment for TB.

• Journal of the Korea Convergence Society
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• v.10 no.3
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• pp.363-371
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• 2019

The purpose of this study is to investigate elementary school students' safety knowledge, safety attitude and safety practice behavior to analyze the relations between them, and to find the factors influencing their safety practice behavior. The study method was conducted by using SPSS/SIN 21.0 program of 468 questionnaire surveyed from March. 1 to March. 15, 2018 in S city. As a result, elementary school students' safety knowledge scored 23.21; attitude 3.58 points; safety practice behavior 2.92 points. Safety knowledge has positive correlation with safety attitude and safety practice behavior. Safety attitude, knowledge to be the factors influencing their safety practice behavior. These influential factors explained their safety practice behavior 23.3%. It is necessary for the educational institutions to develop and utilize the practice-oriented fusion education continuously to improve safety attitude and safety knowledge.

• Sleep Medicine and Psychophysiology
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• v.29 no.1
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• pp.15-20
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• 2022

Objectives: Suicide is the major public mental health concerns all over the world. The comparison of suicide attempters and suicide completers could be the fundamental evidence for the suicide prevention. The aim of this study is to explore the differences between suicide attempters and suicide completers in terms of the stressors, suicide methods, and psychiatric diagnosis. Methods: Two types of secondary data were collected for the analyses. Data of the suicide attempters (n = 680) were gathered by intensive reviewing the medical records of Samsung Medical Center, Seoul, Republic of Korea. Data of suicide completers (n = 11,722) were collected by the psychological autopsy data which were gathered by Korean Foundation for Suicide Prevention. Suicidal methods, psychiatric disorders and stressors before suicidal attempt were compared between suicide attempter and completers. Results: Suicide completers were older and male predominant compared to suicidal attempt. Hanging or gas intoxication were more commonly used in the suicide completion, while wrist cutting or drug intoxication were more common in suicide attempters. All types of stressors were found to be high in suicide completers than suicide attempters. However, the proportion of economic and physical stress were greater in suicide completers, while the proportion of family stress were greater in suicide attempters. According to the recorded diagnoses, the rates of depressive disorders, sleep-wake disorders, substance-related disorders were higher in suicide completers, while the rates of anxiety disorders and trauma- and stressor-related disorders, bipolar and related disorders and somatic symptom disorders were higher in suicide attempters. However, after controlling the gender and age, there were no significant differences in diagnosis between suicide attempters and suicide completers. Conclusion: These findings implicate that suicide attempters and completers differed in suicide methods and type of stress. The results suggests that economic stressors, physical illness might raise the risk of suicide completion.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.2B
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• pp.138-143
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• 2003

One of the important design issues for IP routers responsible for packet forwarding in computer networks is the route-lookup mechanism. For each incoming packet, IP routing requires that a router performs a longest-prefix-match address lookup in order to determine the next hop that the incoming packet should be forwarded to. In this paper, we present a new scheme which applies the hashing function for IP address lookup. In the proposed scheme, the forwarding table is composed of multiple SRAMs, and each SRAM represents an address lookup table in each prefix. Hashing function is applied in order to find out the matching entries from the address lookup tables in parallel, and the entry with the longest prefix match among them is selected. Simulation using the MAE-WEST router example shows that a large routing table with 37000 entries can be compacted to a forwarding table of 300 Kbytes in the proposed scheme. It is also shown that the proposed scheme achieves one route lookup every 1.93 memory accesses in average.

• Journal of the Korea Convergence Society
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• v.11 no.10
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• pp.409-416
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• 2020

The purpose of this study is to investigate nursing home caregivers' safety knowledge, safety attitude and safety performance; then to analyze the relations between them, and to find the factors influencing the caregivers' safety performance. The study method was conducted by using SPSS WIN 21.0 program of 134 questionnaires surveyed in S city. A positive correlation was found with caregivers' safety knowledge and safety attitude. Additionally safety attitude has positive correlation with safety performance. No correlation was found between safety knowledge and safety performance. These influential factors explained their safety practice behavior 36.1%. Based on the results of this study, it is necessary to establish a policy that can form a proper safety culture in the nursing home as well as repetitive training centered on practices that can affect the safety performance of caregivers.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.4
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• pp.79-85
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• 2009

This paper describes the degradation properties of ZnO surge arresters impressed by lightning impulse currents. To investigate the deterioration behaviors of ZnO surge arresters due to lightning surges, the 8/20[${\mu}s$], 2.5[kA] standard lightning impulse currents were injected to the ZnO surge arrester under test. The power frequency AC and DC leakage currents flowing through the ZnO surge arresters with and without the injection of lightning impulse currents were measured. As a result, the leakage currents are increased and the asymmetry of the AC leakage current is pronounced as the number of injection of the impulse current increases. The ZnO grain of the surge arrester without the injection of lightning surges are uniform but the ZnO grain of the ZnO surge arrester with the injection of lightning impulse currents are deformed. Also, it was found that the decrease of the $Bi_2O_3$ due to the lightning impulse current leads to the lack of grain boundary layer and the current concentrated by the lack of grain boundary layer play an important role to degrade nonlinear property of ZnO surge arrester blocks.

• Child Health Nursing Research
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• v.8 no.2
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• pp.195-203
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• 2002

This study was done to evaluate the need and satisfaction for nursing care of the families with their hospitalized children. The data were collected through the questionnaire from March 15, 2002 to April 7. Subjects were the 103 families caring for their hospitalized children at pediatric ward in two university hospitals in Daegu. The nursing need instrument was developed by Seo(1999) and modified by the researcher of this study based on the classification of nursing care area(nursing assessment, direct nursing, education and counseling, and facilities and environment). The nursing satisfaction instrument was developed by Wandelt & Ager(1974) and modified by Park(1994) based on classification of nursing care area (psychosocial care, physical care, general care, professional care, and communicative care). The data were analyzed for mean, percent, t-test, ANOVA, and Pearson correlation coefficient using SAS program. The results are summarized as follows: 1. The scores in the nursing need showed in the Direct nursing(3.41±.42), Facilities and Environment(3.38±.46), Education and Counseling (3.35±.40), and Nursing Assessment(3.14±.41) area in order. 2.The scores in the nursing satisfaction showed in the Psychosocial care(3.70±.74), Commu- nicative care(3.60±.72), General care(3.42±.76), Professional care(3.38±.82), and Physical care(3.32±.70) area in order. 3.General characteristics of families which influence on the satisfaction showed a significant difference according to their educational(F=5.63, p=.001) and economical level(F=4.47, p=.006), and hospitalized experience(t=2.30, p=0.02). 4. There was no correlation between the nursing need and the nursing satisfaction.

• Journal of Family Resource Management and Policy Review
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• v.21 no.3
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• pp.77-95
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• 2017

The purpose of this study is to examine the factors related to leisure time to understand middle-aged one-person households. Data are from the recent survey of lifetime use in 2014 by Statistics Korea(N=1,138). Middle-aged one-person households aged 40-59 years were categorized into four groups by marital status (unmarried/married/widowed/divorced). Major results were found as follows: First, the total leisure time per day was 238 min in the middle-aged one-person households. The majority of the total leisure time was spent on 'fellowship & leisure activities'(204 min on weekdays, 283 min on weekends). Especially, time spent on real-time TV watching hours was the longest, as long as 89 min on weekday and 150 min on weekends. Second, gender differences were significant in terms of leisure time use in the middle-aged one-person households. Females spent less time on leisure than their male counterparts on both weekdays and weekends. In addition, gender differences related to marital status were significant. Third, on weekdays, the determinants of leisure time use among the middle-aged one-person households were health and type of employment for 'participation & volunteer activities', and gender, age, marital status, and type of employment variables for 'fellowship & leisure activities.' On weekends, time spent on 'participation & volunteer activities' were influenced by marital status, residential area, and type of employment, while time spent on 'fellowship & leisure activities' were significantly related to gender, type of employment, type of job, holiday system, and income.