• The Journal of the Acoustical Society of Korea
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• v.37 no.3
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• pp.147-155
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• 2018

In this paper, we tried to find out sound quality metrics to express discomfort of overload excavator noise and to develop sound quality indexes through multiple regression analysis by using them. For this purpose, the interior noise of cabin under overload condition was recorded for six excavator models with different noise properties and Jury test was carried out by PCM (Paired Comparison Method) and MEM (Magnitude Estimation Method). Jury test result with low consistency was classified into two groups with different preference tendencies by cluster analysis and multiple regression analysis was conducted in order to find out which sound quality metrics have significant effects on discomfort(low preference). As a result, we figured out that the sound quality metrics to express the discomfort were the partial loudness (= $PN_{10Bark}$) between 0 and 10 Bark in case of group1 and the difference between engine noise(= $dB_{EG}$) and hydraulic system noise ($dB_1$) in case of group2. Using the results of preference ranking and tendency analysis of PCM followed by the correlation analysis between PCM and MEM, the more reliable results were adopted by excluding the data with low consistency obtained from Jury test via MEM.

• Journal of Convergence for Information Technology
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• v.11 no.8
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• pp.92-99
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• 2021

Light-scattering fine particulate matter monitors can measure particulate matter (PM) concentrations in every second and can be designed in a portable size. They can measure the concentrations of various PM sizes (PM_1.0, PM_2.5, PM_4.0 and PM₁₀) with a single sensor. They measure the number and size of particulate matters and convert them to weight per volume (concentration). These devices show a large error for asian dust. This paper proposes a scheme that compensates the PM_2.5 concenstration error for asian dust by multiple linear regression machine learning in light-scattering PM monitors. This scheme can be effective with only two or three types of PM sizes. The experimental results compare a beta-ray PM monitor of national institute of environmental research and a light-scattering PM monitor during a month. The correlation coefficient (R²) of theses two devices was 0.927 without asian dust, but it was 0.763 due to asian dust during the entire experimental period and improved to 0.944 by the proposed machine learning.

• 한국노년학
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• v.28 no.4
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• pp.969-989
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• 2008

This study attempts to explain how depression among community elderly relate to suicidal ideation and whether or not the psycho-social characteristics of elderly persons moderate the relationship between these two variables. This study was conducted in Seoul, Busan, and Daegu and included 273 persons 65 years and above who were using senior welfare centers in the communities. For the questionnaire and analysis, this research uses the Health Care, Life Event, Self-esteem, Family Assessment scales. This research utilizes a wide range of statistical analyses, such as descriptive analysis, Pearson's correlation, reliability analysis, multiple regression, and general linear modeling. The calculations employed the use of SPSS/PC+ 12.0. This research indicates, among other things, that elderly persons with a high level of depression and psycho-social characteristics show a tendency toward higher suicidal ideation and that the level of self-esteem, life event, and family communication plays a moderating role in the relationship between depression and suicidal ideation among community elderly. In conclusion, elderly persons who experienced with a high level of psycho-social characteristics shows a relatively greater tendency toward suicidal ideation when compared to elderly persons having a low level of psycho-social characteristics. The intervention's effectiveness in reducing suicidal ideation can reinforce self-esteem, and cope with stressful life events and family discord as prevention strategy to reduce risk factors for suicide in late life.

• Journal of the Korea Convergence Society
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• v.9 no.8
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• pp.343-353
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• 2018

The purpose of this study was to identify the effects of clinical nurses' emotional labor and professionalism, and verify the moderating effects of social support on nursing performance. A survey was conducted with 230 nurses working in general hospitals using self-reporting questionnaires in Seoul. It was found that the number of years in current department, professionalism, social support, and deep acting of emotional labor were affecting nursing performance. Social support perceived by clinical nurses moderates the deep acting of emotional labor and it positively influenced nursing performance. Results of this study indicate that nurse managers should focus on increasing nurses' professionalism and social support, and create working environments where nurses do more deep acting of emotional labor in order to increase nursing performance. This study contribute nurse managers to recognizing the impact of emotional labor, professionalism, and social support on nursing performance. Practical programs for increasing clinical nurses' professionalism, social support and decrease emotional labor is required to be developed in further research.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.2
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• pp.108-116
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• 2014

With the increasing the importance of emotional quality of vehicle, the sound quality of systems with electric motor components has become increasingly important. Electric motors are used for windows, seats, sun roof, mirrors, steering columns, windshield wiper and climate control blowers, etc. In this paper, a study was conducted to identify sound quality factors that contribute to customer's satisfaction and preference of the window lift system. Jury test for subjective evaluation was carried out and sound quality index was developed. Averaged sound pressure level and sharpness were significant factors when glass moves down. Also, maximum loudness at stop section and averaged loudness were significant factor when glass moves up. Next, noise source identification was carried out using beam forming method during glass transferred section and impulsive noise at stop section. Several improvement methods were applied using the source identification result. And finally, the degree of sound quality improvement was judged using sound quality index.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.2
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• pp.111-122
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• 2010

As the Jamsu-bridge and the floodplains of the Han River can be flooded during the rainy season, the exact prediction of the peak flood time is very important for mitigation of flood hazard. This study analyzes the effect of outflow of Paldang Dam and tide of Yellow Sea on the Han River. A target area is from the Paldang dam to Jeonryu gauging station. Water level of Jeonryu as a downstream boundary condition was estimated through multi linear regression analysis with outflow of Paldang dam and tide level of Incheon, because it was influenced by both a tide of Yellow Sea and outflow of Paldang dam. In this study, Water Level Rising Travel Time of the Jamsu-bridge and some floodplains in the Han River are estimated. Also, The second order polynomial expressions for relationships of outflow of Paldang Dam and Water Level Rising Travel Time were developed considering the outflow of Paldang dam and tide of Yellow Sea.

• Journal of Internet of Things and Convergence
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• v.5 no.2
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• pp.55-66
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• 2019

Objectives: The purpose of the study was to identify the factors influencing the nursing students' Clinical Competency. Methods: A sample of convenience was 185 nursing students, and a questionnaire was used to measure their self-leadership, critical thinking disposition, self-directed learning ability, problem solving ability and clinical competency. Results: A significant positive correlation was found among clinical competency, self-leadership, critical thinking disposition, self-directed learning ability and problem solving ability. Grade of which the participant was in, interpersonal relationship, critical thinking disposition, problem solving ability, and self-directed learning ability were significant predictive variables of which accounted for 53% of the variance in clinical competency. Conclusions: The results from this study can be used to develop the programs for improving clinical competency.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.6_1
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• pp.529-538
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• 2012

By using an algorithm derived by a multiple linear regression analysis, a technique for filtering was developed; and by using the developed technique, the results of conducting filtering of the raw data collected via scanning with a terrestrial LiDAR the actual sloped terrain was analyzed. As such, when filtering was applied by dividing the observation areas into two areas with the topographical line as a reference in order to improve the filtering accuracy, it was seen that the filtering accuracy improved by about 8.73% as compared to when filtering was applied without dividing the observation area. In addition, considering the fact that the accuracy improved by 5~7% when the sloped sides of a multicurvature topography were divided and a complex filtering applied as compared to when filtering was applied for the entire area or by regions, it can be asserted that the accuracy was higher when a complex filtering was conducted by dividing the sloped areas where the slope is not constant due to the multi-curvature of topography.

• Proceedings of the KAIS Fall Conference
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• 2010.05b
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• pp.863-866
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• 2010

병원 근로자의 VDT 자각 증상에 대한 선행연구를 보면 대부분이 간호사 관련 직종으로 한정되어 있고, 방사선사에 대한 연구는 수행되지 않았다. 본 연구는 2009년 10월 15일부터 11월 2일까지 대전광역시에 소재하고 있는 종합병원에 VDT 작업을 시행하는 보험심사, 원무, 의무기록, 전산, 행정부서 근무자와 방사선사를 대상으로 구조화된 설문지를 활용하여 분석하였다. VDT 증후군 자각 증상 점수를 종속변수로 한 다중선형회귀 분석 결과 관련요인으로 안관련 증상에 영향을 미치는 요인을 보면 성별, 건강염려, 일상생활 방해이며, 전신증상은 운동, 스트레스, 건강상태 인지 관련, 근골격 증상에서는 임상경력 6-10년, 대인관계, 건강상태 인지 관련 건강염려와 일상생활 방해로 나타났으며, 통계적으로 유의한 차이를 보였다. 피부 증상으로는 연령 20-29세, 결혼여부, 식습관, 건강상태 인지 관련 소화 정도와 일상생활 방해로 나타났으며, 심리 증상으로는 성별, 결혼 여부, 스트레스, 소화 정도, 일상생활 방해로 나타났으며, 통계적으로 유의한 차이를 보였다. 타부서 근로자와 방사선사의 VDT 증후군 자각점수 차이가 크게 나타나지 않았으며, 이는 방사선사의 업무가 VDT 환경으로 변함으로써 VDT 증후군 자각 증상이 일어날 수 있다는 것을 나타내는 것이다. 이는 정기적인 순환근무를 시행함으로써 VDT 환경에 지속적인 노출을 피하는 것이 예방 대책이라 할 수 있다.

• Journal of Convergence for Information Technology
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• v.7 no.4
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• pp.171-183
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• 2017

The purpose of the study was to identify the factors influencing the nursing students' job-seeking stress. A cross-sectional descriptive survey, using a structured questionnaire, was used to collect data from Sep. to Oct. 2016. A sample of convenience was 246 nursing students and a questionnaire was used to measure their major satisfaction, CDMSE, self-esteem, ego-resiliency, and job-seeking stress. A significant negative correlation was found among job-seeking stress, major satisfaction, CDMSE, self-esteem, and ego-resiliency. Grade of which the participant was in, self-esteem, academic achievement, experience of clinical practice, and family economic status were significant predictive variables of which accounted for 46.1% of the variance in job-seeking stress. The results from this study can be used to develop programs for job-seeking stress management.