• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.10a
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• pp.171-173
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• 2018

The poor working conditions of transit drivers not only lead to mental stress and fatigue accumulation of workers, but also to the main causes of mass transit accidents. Stress and fatigue accumulation are closely related to the vital signs because they affect the psychological and physical health. In this paper, we designed a digital garment which can measure driver's health condition by measuring electrocardiogram, pulse rate and body temperature. Also proposed a system that transmits the measured bio-signal to the smartphone app via Bluetooth and transmits the current position of the driver to the server by using the built-in GPS of the smartphone, assuming there is something wrong.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.8
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• pp.1-8
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• 2004

Experimental results are presented for gate oxide degradation, such as SILC and soft breakdown, and its effect on device parameters under negative and positive bias stress conditions using n-MOSFET's with 3 nm gate oxide. The degradation mechanisms are highly dependent on stress conditions. For negative gate voltage, both interface and oxide bulk traps are found to dominate the reliability of gate oxide. However, for positive gate voltage, the degradation becomes dominated mainly by interface trap. It was also found the trap generation in the gate oxide film is related to the breakage of Si-H bonds through the deuterium anneal and additional hydrogen anneal experiments. Statistical parameter variations as well as the “OFF” leakage current depend on both electron- and hole-trapping. Our results therefore show that Si or O bond breakage by tunneling electron and hole can be another origin of the investigated gate oxide degradation. This plausible physical explanation is based on both Anode-Hole Injection and Hydrogen-Released model.

• Research in Community and Public Health Nursing
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• v.30 no.2
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• pp.130-140
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• 2019

Purpose: The aim of this study is to explore levels of suicidal ideation and identify subgroups of high suicidal risk among the depressed elderly in Korea. Methods: A descriptive cross-sectional design was adopted on secondary data from the 6th (1st year) Korean national health and nutrition examination survey (KNHANES). A total of 239 depressed elders aged 60 or over who participated in the KNHANES. The prevalence of suicidal ideation and its related factors, including sociodemographic, physical, psychological characteristics and quality of life (EQ-5D index) were examined. Descriptive statistics and a decision tree analysis were performed using the SPSS/WIN 23.0 and SPSS Modeler 14.2 programs. Results: Of the depressed elderly, 28.9% had suicidal ideation. Three groups with high suicidal ideation were identified. Predictive factors included perceived stress level, household income level, quality of life and restriction of activity. In the highest risk group were those depressed elderly with moderate and low levels of stress, less than .71 of EQ-5D index and restriction of activity, and 80.0% of these participants had suicidal ideation. The accuracy of the model was 80.8%, its sensitivity 85.9%, and its specificity 68.1%. Conclusion: Multi-dimensional intervention should be designed to decrease suicide among the depressed elderly, particularly focusing on subgroups with high risk factors. This research is expected to contribute itself to the policy design and solution building in the future as it suggests policy implications in preventing the suicide of the depressed elderly.

• Journal of the Korean Institute of Educational Facilities
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• v.26 no.3
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• pp.15-23
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• 2019

This study aims to suggest a Biophilic classroom design of high school to obtain attention restoration for students. The learning space for youth in the modern society is composed of dry artificial structures. This space is considered to be a space that can not relieve stress caused by learning. "The Attention Restoration Theory" is divided into "Directed Attention" of humans, which is the cause of fatigue and stress, and "Involuntary Attention" as a solution to it. "Involuntary Attention" takes place in a rest state and helps the brain recover when exposed to nature. And the core of "Biophilic-Design Theory" is that humans can recover physical and mental conditions when exposed to nature. The purpose of this study is to apply "The Biophilic-Design Theory" that emphasizes the importance of exposure to nature to the educational space and plan the space where the 'Attention Restoration' can be achieved. The research method is as follows. First, we review previous studies related to "The Biophilic-Design Theory" and "The Attention Restoration Theory". Second, we analyze the application examples of "The Biophilic-Design Theory" and "The Attention Restoration Theory" in domestic and foreign educational spaces. Third, the concept of educational space is set up based on the elements derived from previous studies. Finally, we propose the planning direction of classroom design based on Biophilic-Design. The following conclusions were drawn. First, The creation of the education space to restore the learner's attention requires a visual space plan that utilizes natural elements such as natural light, artificial light, plants, and natural materials that can directly experience nature. Second, the direction in which students in the classroom can be "The Attention Restoration Theory" should consider the use of indirect natural elements that bring the surrounding natural landscape into the interior. This study will be used as the baseline data for the spatial design and planning of education facilities based on Biophilic-Design.

• Korean Journal of Culture and Social Issue
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• v.29 no.1
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• pp.75-99
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• 2023

The current study aimed to explore the suicidal behaviors and risk factors of completed suicides using psychological autopsy and use them as index variables to classify suicidal types. In addition, this study looked into the influential factors that affect each suicidal type. related to suicidal behaviors and suicidal risk factors by psychological autopsy. In addiction, the distinctions among the classes were analyzed. For this, psychological autopsies were conducted on the families and the close ones of 128 completed suicides. Then, the index variables were finally chosen for classifying suicidal types. The selected index variables for suicidal risk factors were mental disorders, suicide/self-harm, significant changes in physical appearance, marital conflict, adjustment and relationship issues at work/school, unemployment/layoff, jobless status and serious financial problems. The selected index variables for suicidal behaviors were expressing their suicidal attempts, writing suicidal notes, asking for help, the time/place/method of suicidal behavior, past suicidal/self-harm experience and the first person who witnessed the suicide. The Latent Class Analysis(LCA) and the 3-step method were used for classifying suicidal types. Then external variables(financial changes, cohabitation, existence of stressors, changes in stress level or relationships and family members with mental disorder/alchohol problems/ physical disorders, and work/school stisfaction) were applied for distinguishing classes. As a result, 5 classes(financial problems, adjustment problems, complex problems, psychiatric problems, and response to event[s]) were revealed on suicidal behaviors and 3 classes(residence- suicidal attempt- found by family, nonresidence- nonsuicidal attempt- found by acquaintances, residence- nonsuicidal attempt- found by family) were presented on suicidal risk factors. External variables such as gender, marital status, cohabitation, changes in relationships significantly differentiated among the 3 classes. Especially, class 3(residence- nonsuicidal attempt- found by family) tended to cohabit with others, were married, and had a significantly high level of interpersonal conflicts. When comparing the 5 classes of suicidal risk factors, auxiliary variables such as economic changes, cohabitation, stress, relationship changes, and family-related problems, and school/work satisfaction significantly differentiated the 5 classes. Especially class 3 (complex problems) experienced comparatively less family-related problems, but showed an aggravating level of personal stress. Suicial prevention strategies should be provided considering the characteristics of each class and the influential factors.

• 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.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.3046-3051
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• 2011

The third-rail system is an important device supplying power directly to the Maglev train through physical contact with the collecting shoe. It is directly related to safety and reliability for the running of Maglev. However, most the third-rail system used in Korea depend on foreign product or technologies, Korea Urban Maglev in the development of appropriate power feeding is urgent. In particular, the turnout section is the weakness point in the system because bending force by turnout section movement and fatigue caused by repetitive motion as well as the expansion by temperature, the forces by Maglev collecting shoe is added th the third-rail. Therefore, this paper proposes the third-rail system appropriate for Korean Urban Maglev of turnout section. To verify the structural stability of POSCO ICT third-rail system, the finite element analysis and physical testing was performed. The third-rail is fixed on each side of the turn-out section steel structure by epoxy insulation supporter and the integral behaviors are occurred. Therefore, the maximum horizontal displacements of each support are investigated and then, it is applied to finite element model of the third-rail to investigate the moments and stress. Also, the bending test about one million times and Expansion Joint for the third-rail was performed. The third-rail system safety and reliability was identified by test line on Korea Institute of Machinery & Materials in Deajeon for under the actual usage environment such as the Maglev and turn-out operation.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5849-5855
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• 2012

Objective: The purpose of this study was to determine pretreatment effects of moderate-term endurance training before the various dosages (10 and $20{_{mg.kg}}^{-1}$) of DOX on a heat shock protein ($HSP_{70kda}$) and cardiotoxicity in heart tissue. Methods: Forty-eight male rats were randomly assigned to nontraining (NT) and training (T) groups and three subgroups; $DOX{_{10mg.kg}}^{-1}$ and $DOX{_{20mg.kg}}^{-1}$ and saline treatment. The training program included treadmill running between 25-39 min/day and 15-17 m/min, 5 days/wk for 3 wk. Result: DOX administration, in particularly with $20{_{mg.kg}}^{-1}$, caused up-regulation of oxidants and cardiac damage (MDA, CK, CPK-MB and CK/CPK-MB) and down-regulation of cardioprotection ($HSP_{70}$, SOD) markers, as compared to NT+saline group. Pretreatment effect of treadmill running endurance exercise in the presence of DOX with $10{_{mg.kg}}^{-1}$ caused a significant increase in $HSP_{70}$, SOD and a significant decrease in MDA and insignificant decrease in CK, CPK-MB and CK/CPK-MB, in comparison $T+DOX_{10}$ with $NT+DOX_{10}$ group. However, there was no significant difference between $T+DOX{_{10mg.kg}}^{-1}$ and $T+DOX{_{20mg.kg}}^{-1}$ in the aforesaid markers. Conclusion: Dox-induced cardiotoxicity is related to oxidative stress. Our study suggests that pretreatment with endurance exercise may be considered as a potentially useful strategy to improve myocardial tolerance against single dose DOX-induced oxidative damage.

• Journal of Oriental Neuropsychiatry
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• v.12 no.2
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• pp.27-35
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• 2001

Objective : Doctors who treat women in childbed have to pay attention to postpartum blues and depression which women in childbed can suffer from, as well as recovery of physical function. Methods : Subjects were 107 females who admitted in Woosuk Hospital of Oriental Medicine from September, 2000 to October, 2001 and made out the question paper within 10 days after delivery. The paper included EPDS(Edinburgh Postnatal Depression Scale) and many items known to be the factors related to postpartum blues and depression. Results : The rate of postpartum depression assessed by EPDS was 16.8%. As the result of analysis, there were significant statistic corelations between each group assessed by EPDS and age parity relation with husband yes or no living with parents-in-law. But there were no significant corelations between each group assessed by EPDS and education religion yes or no occupation delivery method sex of infant marriage type yes or no rearing the infant. Conclusions : We recognized that insufficiency- of delivery experience and stress due to bad adaptation after delivery are possible to be risk factors of postpartum blues and depression. More research should be taken on the corelation between postpartum depression and yes or no living with parents-in-law, because this result is opposite to the trouble between mother-in-law and daughter-in-law. In addition, more research is needed on corelation between physical condition, oriental-diagnosis of women in childbed and postpartum depression.

• Journal of the Korean Society of School Health
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• v.33 no.2
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• pp.125-138
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• 2020

Purpose: The study investigated the effect of adolescent health behavior on the prevalence of current allergic diseases. Methods: The subjects were 57,303 middle and high school youth. Data were analyzed using Rao-Scott χ² test and complex sample logistic regression analysis. Results: While controlling the affect of the general characteristics of the subjects, health behaviors affecting the current prevalence of allergic diseases were smoking, drinking, physical activity, eating habits, drug abuse, and mental health. Smoking behaviors affecting the current prevalence of allergic diseases were lifetime smoking experience, smoking days, liquid e-cigarette lifetime smoking experience, number of liquid electronic cigarette smoking days, e-cigarette lifetime smoking experience, e-cigarette smoking days, amount of smoking, second-hand smoking and drinking behaviors were lifetime drinking, drinking days, the amount of drinking, and severe drinking. Variables such as physical activity exceeding 60 minutes days, intake of energy and sweet drinks, water intake, habitual drug use and mental health behavior such as stress perception, weekday sleep time, subjective sleep satisfaction, depression, suicidal thoughts/ plan/ attempts affect current allergic diseases (p<.001). Conclusion: The results showed that current allergic disease related health behaviors in Korean adolescents. Therefore, considering these factors, it may be helpful to facilitate a health promotion plan for prevention and management of such diseases and to promote evidence-based health practices at school.