• 대한인간공학회지
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• 제20권2호
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• pp.71-82
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• 2001

Twisting posture in lifting tasks has been identified as a risk factor of low back pain. However, it has been usually estimated in terms of compressive stress or muscular activity. Thus, this study was conducted to predict the influence on muscular fatigue during lifting simulation. Fifteen young and healthy subjects were recruited and performed isometric trunk exertions during upright standing, two-level flexions and five-level asymmetric twisting conditions. EMG signals from five primary trunk muscles in right part of body were collected during 20sec for 45 different lifting conditions. RMS(root mean square) and MPF(mean power frequency) parameters were used to analyze the EMG signals. Twisting postures were significant in right erector spinae(ERSR), right latissimus dorsi(LATR), right internal oblique(INOR) for muscular activities. Especially, when trunk was $30^{\circ}$ CCW twisting posture. ERSR and INOR activities increased respectively by 11% and 3%. Regarding the trunk muscle fatigue, we found that MPF shifts in twisting posture increased 2.3 and 2.6 times for ERSR and INOR muscles respectively. Therefore, It is probable for workers to suffer from low back disorders when they were exposed to a extreme twisting posture during prolonged lifting. This study suggests NIOSH(National Institute for Occupational Safety and Health) lifting equation needs the time-duration multiplier in addition to asymmetric multiplier.

• 한국화재소방학회논문지
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• 제26권5호
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• pp.48-53
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• 2012

최소자연발화온도는 가연성액체의 안전한 취급을 위해서 중요한 지표가 된다. 본 연구에서는 ASTM E659 장치를 이용하여 가연성 혼합물인 n-Butanol+sec-Butanol 계의 최소자연발화온도와 발화지연시간을 측정하였다. 2성분계를 구성하는 순수물질인 n-Butanol과 sec-Butanol의 최소자연발화온도는 각 각 $340^{\circ}C$, $447^{\circ}C$로 측정되었다. 그리고 측정된 n-Butanol+sec-Butanol 계의 최소자연발화온도는 제시된 식에 의한 예측값과 적은 평균절대오차에서 일치하였다.

• The Journal of Korean Physical Therapy
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• 제21권3호
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• pp.119-124
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• 2009

Purpose: The National Institute for Occupational Safety and Health (NIOSH) lifting equation (NLE) is a useful tool to ergonomically analyze a workload. The NLE has high reliability and it can assess tasks by analyzing the work process. The purpose of this case study was to try using the NLE to analyze the workload of transferring patients by physical therapists in the hospital setting. Methods: We observed a physical therapist (PT) transferring patients from a wheelchair to a tilt table and a therapeutic table in one day. Two types of patient transferring methods were evaluated; (1) the manual single person method of stand, pivot and transfer, and (2) manual two person lifting under the thigh and grasping the waist for totally dependent patients. Results: The NIOSH lifting indexes of a person grasping the waist during the manual two person lifting were 5.52~4.48 according to the patient's weight. The NIOSH lifting indexes were 3.34 and 4.48 for the tasks performed by the manual single person method. Conclusion: Because transferring patients is not done very frequently, patients transferring tasks by a PT are not included as one of the musculoskeletal disorder related risky work criteria of the Korea Ministry of Labor. But the NIOSH lifting indexes of a person grasping the waist during the manual two person lifting and the manual single person method were over the NIOSH recommended weight limit threshold.

• 한국화재소방학회논문지
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• 제27권3호
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• pp.47-51
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• 2013

폭발한계는 가연성물질의 화재 및 폭발위험성을 결정하는데 주요한 특성치 가운데 하나이다. 많은 유기산류는 연소열과 폭발한계, 화학양론계수와 폭발한계가 상관관계가 있음을 보여주고 있다. 본 연구에서, 유기산류의 폭발하한계와 상한계에 대해 연소열과 화학양론계수를 이용하여 예측하였다. 제시된 예측식에 의한 예측값은 문헌값과 적은 오차범위에서 일치하였다. 제시된 방법론을 사용하여 다른 유기산류의 폭발한계 예측이 가능해졌다.

• 한국화재소방학회논문지
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• 제28권2호
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• pp.64-68
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• 2014

사이클로헥산올의 안전한 취급을 위해, 폭발한계는 문헌을 통해 고찰하였고, 인화점과 발화지연시간에 의한 발화온도를 측정하였다. 그 결과, 밀폐식 장치에 의한 사이클로헥산올의 하부인화점은$60^{\circ}C{\sim}64^{\circ}C$로 측정되었으며, 개방식에서는 $66^{\circ}C{\sim}68^{\circ}C$로 측정되었다. ASTM E659 장치를 사용하여 자연발화온도와 발화지연시간을 측정하였고, 사이클로헥산올의 최소자연발화온도는 $297^{\circ}C$로 측정되었다. 측정된 하부인화점과 상부인화점에 의한 폭발하한계는 0.95 Vol%, 상한계는 10.7 Vol%로 계산되었다.

• 기술사
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• 제30권5호
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• pp.96-104
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• 1997

This study analyze industrial safety and health planning report for manufacture. The purpose of accident analysis is to obtain accurate and objective information about the causes of accidents in order to prevent accidents from reoccurring. This study investigated the causes and conditions of occupational accidents in Korean industry. As the most accidents are occurred in lifting material, the questionnaire analyses about injuries are operated for occur to deal with the Manual Materials Handing. The results show that there are some characteristics in the accidents of Korean industry since 1986: (1) accidents rates tend to have lower since 1983(1994-1.18%, 1995-0.99%, 1996-0.88%), (2) larger companies tend to have lower accident rates than the smaller ones, (3) inexperience is related to high accident rates(1995-51.26%, 1996-48.82%1, because of the careless education for freshman such as OJT which in order to prevent accident, and (4) the body sites most vulnerable to injury are the hands and fingers and increased the back(caused of Back pain). The results of questionnaire analysis show that operator(n= 104) interested in reinforce the back & belly(42.86%). These finding identified in this study can be used to prevent the industrial accidents, and used to improving directions based on analyzed result.

• 한국식품위생안전성학회지
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• 제27권1호
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• pp.18-23
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• 2012

본 연구에서는 4급 암모늄에 속하는 quaternary ammonium chloride와 구연산의 합제인 Citra-$Kill^{(R)}$의 조류인플루엔자에 대한 살바이러스 효과를 확인하기 위해 국립수의과학검역원의 소독제 효력시험 중 바이러스 소독제 효력시험에 따라 수행하였다. 소독제와 조류인플루엔자바이러스를 증류수, 경수, 그리고 유기물 조건에서 반응시킨 후, 중화액을 이용하여 중화시킨 다음, 중화된 용액 0.2 ml를 10일령의 계태아 요막에 주입하여 5일 동안 배양시킨 다음, 요막액을 채취하여 바이러스의 생존여부를 혈구응집반응을 통해 확인하여 소독제의 효력배수를 결정하였다. 본 연구의 결과, Citra-$Kill^{(R)}$은 증류수, 경수, 그리고 유기물 조건에서 각각 2,000, 1,500, 그리고 500배에서 조류인플루엔자바이러스를 불활성화시켜, 조류인플루엔자에 대해 뛰어난 소독효과를 갖고 있는 것이 확인되었다. 따라서 향후, 야외적용시험을 통해 실제적용에 따른 효과를 확인할 필요가 있을 것으로 사료된다.

• 한국가스학회지
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• 제14권5호
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• pp.19-25
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• 2010

본 연구에서는 o-xylene+n-pentanol 및 m-xylene+n-hexanol 계의 인화점을 Tag 개방식 장치(ASTM D1310-86)를 이용하여 측정하였다. 실험값은 Raoult의 법칙, van Laar 및 Wilson 식을 이용한 계산된 값들과 비교하였다. 그 결과, 최적화법에 의한 예측값이 Rauolt의 법칙에 의한 계산 보다 실험값에 더욱 근접하였다. 또한, van Laar 식을 사용한 최적화법이 Wilson 식에 의한 최적화법 보다 실험값에 대한 모사성이 우수하였다.

• 한국화재소방학회논문지
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• 제27권5호
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• pp.70-74
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• 2013

인화점은 액체 용액의 폭발과 화재의 위험성을 특징짓는 가장 중요한 물성치 중 하나이다. 액체 혼합물의 최대인화점은 용액을 구성하는 개별 성분들의 인화점보다 높은 것을 의미한다. 본 연구에서는 2-pentanol+acetic acid 계의 인화점을 Seta flash 밀폐식 장치를 통해 측정하였다. 이 계는 최대인화점 현상을 나타내었다. 또한 인화점은 Raoult의 법칙을 이용하여 예측하였고, van Laar 식과 Wilson 식을 활용한 최적화 기법에 의해서도 예측하였다. 최적화 기법에 의한 예측 방법이 Rauolt의 법칙에 의한 예측 방법 보다 측정치를 잘 모사하였다.

• 한국식생활문화학회지
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• 제20권6호
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• pp.652-660
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• 2005

This study is performed for the investigation of management of personnel, wages, welfare, communication, labor, safety, treatment improvement according to assigned working places(primary, middle and high school). This study is based on the final analysis summarized on the 285 questionnaire answered by employee for school foodservice in Buchon city after distributing total 500 questionnaire. The conclusion of this analysis of study is as following. This report says the reason of this mind is caused by hard work. This investigation says they feel to be compensated with low wages on the contrary their hard working and this caused them to demoralize and increase to give up their jobs. The long tenn vacation like childcare vacation is newly established by present improvement of working condition but this improvement action is ineffective. Many of them are feeling to a fatigue and ill health and the condition of occupational disease as hard work. The present improvement of irregular employee treatment like above cases is not effective. So the rewards and payment shall be considered according to their hard work and the working condition must be improved practically for the settlement of their job without leaving.