• Journal of the Korean GEO-environmental Society
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• v.11 no.12
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• pp.5-11
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• 2010

If the groundwater in rock joint is changed into ice, it induces the stress increment by volume increase. Also, if the ice is changed into groundwater again, the stress in joint decreases by volume decrease. The accumulated displacement and fatigues of joints are increased by the stress-hysterisis, induced from the continuous frost-thawing. Also the shear strength is decreased by them continuously. The stress-hysterisis is affected by the atmospheric temperature changes, whose behavior is visco-elasticity, usually. Therefore, Kelvin model could be used to analyze the frost-thawing behavior in winter. The measured data of total 5 points are examined, which are composed of 3 points of shallow joints and 2 points of deep joints. Because shallow weathered rocks have many joints, a lot of Kelvin model are connected and the behaviors are complicated. In case of deep joints, simple Kelvin model is applied and the behaviors are also simple.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.542-545
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• 2022

Recently, the Act on the Punishment of Severe Disasters has drawn attention to the construction environment. A common way to check the safety management of the construction site is for workers to check the site with their own eyes. However, this method is inevitably affected by the limitations of workers' abilities, resulting in fatigue and reduced work efficiency. For this reason, it cannot be an efficient method. Thus, we intend to help the working environment and construction site safety through this study, by proposing an efficient ICT safety management system that can supplement the above methods. In this paper explain the design of the access management system using RFID and the field information monitoring method through noise sensors and fine dust sensors. In addition, we propose a system that can prevent accidents between heavy equipment and people with a PIR sensor, and prevent safety accidents by grasping the slope of the building being worked through a gyro sensor.

• Journal of dental hygiene science
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• v.9 no.4
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• pp.453-459
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• 2009

The purposes of this research were to evaluate the relationships of between characteristics of noise and annoyance of dental hygienist by noise in dental clinic. To investigate the dental clinic workers' reactions to noise when occurred in dental clinic, the noise level test in dental clinic and questionnaire were taken. As a result of noise evaluation, It shows that the range of noise level was 67.7~78.3dB(A) and frequency was very high (more than 4KHz). It's seem to be begins occurrence of stamina-loss, contraction of peripheral blood vessel, decrease of adrenocortical hormones. Most of respondents were affected by noise: 67% of respondents were nervous about noise and the rest of respondents were bearable. Analysis by NR-curve showed that it was exceed the noise permit level in working space. As a result of correlation - test, the more exposed dental hygienist to noise, the more felt the unpleasantness and fatigue. It's hard to sufficient explanation to patients about the dental treatment. So it's thoughts that insufficient explanation will negative impact on the patients' satisfaction and increase competitiveness in dental clinics. To remedy a unpleasantness and fatigue of noise in dental hygienist, it's considered that making an offer the ear protection and choosing the low noise-vib. equipment and using the masking effect. Therefore, It can be provide a pleasant working environment with dental hygienist and It will have a great advantage to dental clinics to improve their competitiveness.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.51-51
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• 2017

정식기는 주로 노외에서 사용되므로 사용자에 따라 극심한 작업환경 하에 놓일 수 있다. 사용 중 정식기 호퍼에 토양이나 자갈, 돌 등에 의해 반복적인 하중이 가해지거나 순간적인 충격하중이 가해져 취약부가 파손될 가능성이 있으므로, 토양과 직접 맞닿는 삽날부의 경우 내구성을 고려한 설계/제작이 필수적이다. 본 연구에서는 보행형 반자동 정식기 개발에서 고추묘와 같은 초장이 긴 작물의 묘를 효과적으로 이식할 수 있도록 개선된 삽날에 대해 기존 삽날과 강도 및 강성을 비교하고, 그 결과가 삽날의 내구성에 미칠 영향에 대하여 고찰하였다. 실험에는 양날 개폐 방식의 기존 및 개선삽날 2종이 사용되었으며, 각각 3회씩 정적 강도를 평가하였다. 실제 정식기 사용시 하중이 가해지는 방향은 삽날에 수직한 방향의 압축하중으로 이를 모사하여 일정변위 속도로 삽날에 하중을 가하였으며, 시험 진행시 DAQ 시스템을 통해 실시간으로 하중 및 변위 데이터를 저장하여 시험 종료 후 해당 데이터를 이용하여 $P-{\delta}$ 선도를 도출하였다. 시험 결과 기존삽날의 평균 최대하중이 개선삽날에 비해 높은 것으로 나타났으며, 최대 하중이 나타나는 지점의 변위의 경우, 기존삽날이 개선삽날에 비해 짧게 나타났다. 정적 강도측면에서 개선삽날이 기존삽날에 비해 최대 강도가 낮은 것으로 판단할 수 있으나, 실제 호퍼의 내구성에 영향을 줄 수 있는 주요 인자는 반복적으로 가해지는 비교적 낮은 수준의 충격하중으로 볼 수 있다. 이러한 관점에서 볼 때 일정 수준 이상의 강도를 가지면서, 기존삽날에 비해 낮은 강성을 가지는 개선삽날이 변형을 통한 충격에너지 흡수로 오히려 삽날 조립체(호퍼)의 내구성 측면에서 유리할 수 있다. 따라서 향후에는 기존 및 개선삽날을 적용한 호퍼에 대해 피로시험을 수행하여 관련 내용을 실험적으로 검증하고자 한다.

• 한국HCI학회:학술대회논문집
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• 2008.02a
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• pp.158-162
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• 2008

Heart rate has many effect by environment factor and body factor and mind factor. Experimental testing decide to make relaxed condition. so It want to get correct data peoples different time and condition in the day so medical mans think relaxed to low Heart rate. but normal heart different from peoples and time. there was noting standard. so Heart rate is really hard to relaxed heart rate. Heart rate pattern must have long time analysis for good result. if you get relaxed heart rate so you don't need long-time analysis. Relaxed heart pattern used for guidance of auditory impulse public got concentration and solve to stress. it chose MC Square and mozart music. Two kind of auditory impulse analysis to make a relaxed Heart rate and relaxed pattern. way of analysis is HRV and minute of heart bit rate. result It have find Guidance to Relaxed Heart rate.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.25 no.4
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• pp.129-146
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• 2014

This study aims to present the effects that a bibliotherapy program based on picture books and paper craft art activities had on middle school students' stress recognition and the changes in their reactions. To this end, we adopted an experimental research design model with pre/post-test measurements of stress recognition and reactions using first grade middle school students with emotional difficulties. The results show that a bibliotherapy program based on picture books and paper craft art activities does have significant effects on the stress recognition and reactions of middle school students. The 5 of 5 sub-domains of the stress recognition had significant difference. The sub-domains are: family environment, friends, study, teacher/school. The 6 of 7 sub-domains of the stress reactions except fatigue had significant difference. The sub-domains are: tention, frustration, anger, depression, somatization, aggression.

• Journal of the Korean Institute of Gas
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• v.25 no.4
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• pp.1-9
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• 2021

The process and facilities of modern chemical plants are becoming increasingly complex, there is possibility of potential risk. Internal chemicals generate stress concentration when operated due to turbulence, laminar flow, pressure, temperature, friction, etc. It causes cumulative fatigue damage, which can damage or rupture chemical facilities and devices. The statistics of chemical accidents found that the highest rate of occurrence was in summer, and in the last five years statistics on chemical accidents, leakage incidents make up a decent percentage of accidents. Chemical leaks can cause serious human damage and economic damage, including explosions and environmental pollution. In this study, based on the leak accident of chemical plant, the risk analysis, and damage effects assessment were estimated using a 3D scanner and FLACS. As a result, if chemicals leak in summer, the risk is higher than in other seasons, the seasonal safety management measures, and countermeasure were estimated.

• Proceedings of the KAIS Fall Conference
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• 2010.11b
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• pp.677-680
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• 2010

본 연구는 경기도 구리시의 2개 초등학교 5, 6학년 학생을 대상으로 시력 저하 실태 및 그와 관련된 요인들을 알아보고 시력 저하 예방교육의 기초자료로 활용하고자 시도 된 연구이다. 자료의 수집은 2009년 11월 1일부터 12월 10일까지 초등학교 5학년, 6학년 학생 793명(남 417명, 여 376명)이었고 2009학년도의 시력검사자료 분석과 문헌 및 기존의 조사도구를 토대로 개발한 자가 보고식 설문지를 이용하여 조사하였다. 자료 분석은 SPSS WIN 12.0(한글판)프로그램을 이용하여 빈도, 백분율, $x^2$-test 및 로지스틱 회귀분석의 통계적 방법으로 분석하였다. 시력저하에 유의한 영향요인으로 좌측시력을 종속변수로 한 경우 중 일반특성에 따른 변수인 부모 및 형제와 자매가 안경 및 렌즈 착용하는 경우, 경제적으로 어려울수록 시력 저하 자가 많았고, 환경특성에 따른 변수인 거실 및 방안밝기가 어두울수록, 컴퓨터 사용 시 실내밝기가 어두울수록, TV의 눈높이 및 컴퓨터 모니터의 눈높이가 높을수록 시력 저하 자가 많았다. 우측시력을 종속변수로 한 경우 중 일반특성에 따른 변수인 부모가 안경 및 렌즈를 착용할수록, 형제 와 자매가 안경 및 렌즈를 착용할수록, 경제적으로 어려울수록 시력 저하 자가 많았고, 환경특성에 따른 변수인 거실 및 방안밝기가 어두울수록, 컴퓨터 사용 시 실내밝기가 어두울수록, TV의 눈높이 및 컴퓨터 모니터의 눈높이가 높을수록 시력 저하 자가 많았다. 안경 및 렌즈를 종속변수로 한 경우 중 일반특성에 따른 변수인 부모 및 형제와 자매가 안경 및 렌즈를 착용할수록, 경제적으로 어려울수록 시력 저하 자가 많았으며, 환경특성에 따른 변수인 거실 및 방안밝기의 실내밝기가 어두울수록, TV의 눈높이 및 컴퓨터 모니터의 눈높이가 높을수록 시력 저하 자가 많았다. 눈 건강상태를 종속변수로 한 경우 중 일반특성에 따른 변수인 경제적으로 어려울수록 시력 저하 자가 많았고, 건강행동특성에 따른 변수인 주관적인 건강상태가 나쁠수록, 눈 피로감이 있을수록 시력 저하 자가 많았으며 환경특성에 따른 변수인 거실 및 방안밝기의 실내 밝기가 어두울수록 시력 저하 자가 많았다. 시력저하관련 요인을 연구한 결과 학생들의 시력 저하 자가 매년 증가하고 있다는 것을 알 수 있었고, 유전적 요인에 의한 시력저하는 개인의 노력에 의하여 사전예방이 어렵지만 환경적 요인에 의한 시력저하는 노력과 관심으로 사전예방이 가능하므로 학생들의 시력건강증진을 위하여 학부모와 학교 및 전문 의료기관이 서로 연계적인 협조 하에 학생들 개개인에 맞는 효율적인 시력증진관리프로그램 개발하는 것이 필요하고, 현행학교시력검사의 정확성을 기하기 위하여 표준화된 시력검사 지침을 개발하여 사용할 필요가 있으며, 지역 및 환경적 배경이 다르다 보니 연구결과가 다르게 나타나는 경우가 있는데 객관적인 결과를 도출하기 위하여 여러 지역의 학생을 대상으로 다양하고 체계적인 연구를 해야 할 필요성이 있다고 생각한다.

• Science of Emotion and Sensibility
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• v.14 no.3
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• pp.459-466
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• 2011

Sleep diseases such as snoring and sleep apnea are physically, mentally harmful and results serious health problems. Snoring, known as breathing noise, is caused by coupled oscillation of the airway when the air passes through the trachea, and sleep apnea is caused by upper airway blockage. In order to solve these problems, many attempts have been made to detect the snoring during sleep and alleviate it. In this study, a new sensing system and analysis algorithm were developed in order to detect snoring sounds correctly under various sleep environments. Two polyvinylidene fluoride (PVDF) vibration sensors were used inside the pillow. The first PVDF sensor detects vibration transmitted through skull caused by snoring. And the second PVDF sensor detects both snoring sounds and ambient noises. The signals of two sensors were acquired through the designed analog circuits, and analyzed for snoring detection. Ten volunteers were participated for the experiment under five different conditions. Data from two PVDF sensors were processed by the established analysis algorithm, and snoring sounds were compared to noises. The results indicated that the energy of snoring is 70% bigger than that of ambient noise, which proves effectiveness of sensing system and analysis algorithm. Further study would be continued for more wide clinical studies with various environment noises. Based on this study, development of anti-snore pillow and sleep monitoring system for comfort sleep could be developed.

• Korean Journal of Environment and Ecology
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• v.30 no.3
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• pp.423-433
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• 2016

This study compared the effect of different types of sounds(no sounds, sounds of nature, music, and sounds of children playing) on profile of mood states(POMS) in a healing forest. Data were collected from 231 respondents selected from among visitors to the 'Healing Field' in 'Jangseong Chukryongsan Pyeonbaek Healing Forest' in October, 2012. Each respondent was exposed to one type of sound. The results showed that there were differences in POMS among the different sound treatment groups. Sounds of children playing showed negative effects on POMS. Unexpectedly, however, sounds of nature and musical sounds had no effects on POMS. These tendencies were consistently found not only for total mood disturbance score (TMDS) but also for POMS by factors (i. e. tension, anger, vigor, fatigue, confusion, depression). Perceived crowding level was positively correlated with TMDS(r=0.568) and POMS by factors (range: r=0.331 - 0.571). This paper discusses the research results and suggests several managerial implications.