• 한국안전학회지
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• 제33권5호
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• pp.28-34
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• 2018

Recently, various engineering approaches have been widely used in the accident investigation field to identify the cause of the accident and to predict damage by accident. Computational analysis is the most commonly used method of accident investigation technique. This technique is mainly used to identify the mechanism of the accident generation and to determine the cause when it is difficult to reproduce the situation at the time of the accident or when it is impossible to perform a reproduction experiment. In this study, The computational fluid dynamics analysis for nitrogen asphyxiation accident generated by defect of building structural between diffusion outlet and cooling tower was performed to determine the inflow path of the suffocation gas, death possibility by concentration of suffocation gas and predicted the time of death due to the accident using 3D modeling and FLACS program. We can quantify diffusion concentration of asphyxiation gas and predict mechanism of death occurrence by accident and evaluate the consequence Analysis through this study. In the future, This method can be widely used in the field of gas safety by improving the reliability and validity of the analysis.

• 대한임상독성학회지
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• 제15권1호
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• pp.47-50
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• 2017

Nitrogen is an inert gas that is harmless to humans under normal conditions. While it is not inherently toxic, nitrogen gas becomes dangerous when it displaces oxygen, resulting in suffocation. Herein, we report a case of a 34-year-old man who attempted suicide by nitrogen asphyxiation who presenting with decreased mental function and agitation. Lactic acidosis and hyperammonemia were observed on presentation at the emergency department, but these improved after a few hours. After 2 days, the patient regained full consciousness, and was discharged without any complications. Survival after asphyxiation due to nitrogen gas is very rare, and these patients are more likely to have poorer outcomes. There is a potential for the increasing use of nitrogen gas as a method of committing suicide because of the ease of access to this gas.

• 한국가스학회지
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• 제24권2호
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• pp.36-43
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• 2020

가스계 소화설비는 경제적으로 매우 유용한 설비이지만 설비를 갖춘 후 장기간 미사용될 경우 용기부식으로 인한 파열 현상과 설비 시스템 작동 오류 등이 나타날 가능성이 있어 큰 위험성을 내재하고 있다. 하지만 소화설비 특성 상, 설비의 정상작동 여부를 확인하기 위한 실험이 불가하여 파열 및 오작동으로 인해 밀폐공간 내에 가스가 일시적으로 방출되면 가스질식으로 인한 큰 인명 피해를 가져올 수 있다. 본 연구에서는 최근 발생한 가스계 소화설비작동 오류로 인한 질식 사망 사고를 바탕으로 사고 메커니즘을 분석하기 위해 실제사고가 발생한 현장에 대해 3D 스캐너와 FLACS를 활용하여 설비 오류로 인한 이산화탄소 가스의 유입경로와 이로 인한 사망 가능성 및 사망에 이르는 시간 등을 추정하였으며 이를 통해 질식사고로 인한 정확한 피해 영향을 평가하고자 한다.

• 한국안전학회지
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• 제7권3호
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• pp.35-42
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• 1992

Ignition energy effects of concentration of mixed gas In closed cylindrical vessel(1, 832㎤) are studied. The ignition energy ranged from 25 Joule to 110 Joule, and hidrogen and methane gases were used for flammable gas at stoichiometric condition with oxygen gas and nitrogen gas (N2) was for inert gas, which concentration was maximum 60% . The explosion pressure, temperature, concentration of product gases were calculated. It is found that - The explosion pressure and explosion velocity increase with ignition energy. - The gradience of explosion velocity with ignition energy is steeper than explosion pressure. - The results of calculation are similiar with results of experiment. - NOx is not serious product gas for methane and hydrogen gas, but CO is serious at certain concentration for methane in asphyxiation.

• 한국산업보건학회지
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• 제28권2호
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• pp.222-229
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• 2018

Objectives: The aim of this study was to evaluate gas concentrations such as oxygen in ginger storage tunnels, which are the causes of asphyxiation in confined spaces and suggest directions for safety and health management at ginger farms. Methods: Five farms in the Seosan and Taean areas which use underground ginger storage tunnels were chosen and examined with a walk-through survey and direct reading device for oxygen, hydrogen sulfide, ammonia, and carbon monoxide. Results: The oxygen concentration in the storage tunnels with no ventilation was found to be under 18% in summer, which may cause health effects. The concentration in those with ventilation was about 19%. The difference in temperature by measurement day had little effect on the concentration of oxygen. Conclusions: Even though some of farms had used compulsory ventilation systems, none of the farms visited possessed any direct reading device for oxygen. Warning systems using a direct reading device can be more effective, helpful, and required compared to ventilation, considering the difficulty and expense of periodical maintenance of ventilation systems and the fact that a farmer can be placed in danger when unaware of the malfunction of the ventilation system. In addition, a warning system may make farmers more cognitive of agricultural safety and health actions while a ventilation system can cause them to become passive and ignorant of workplace hazards.

• 한국농공학회논문집
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• 제62권1호
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• pp.71-81
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• 2020

Enclosed pig house are creating an environment with high concentrations of gas and dust. Poor conditions in pig farms reduce pig weight and increase disease and accidents for livestock workers. In the pig house, the high concentration of harmful gas may cause asphyxiation accidents to workers and chronic respiratory disease by long-term exposure. As pig farm workers have been aging and feminized, the damage to the health of the harsh environment is getting serious, and real-time monitoring is needed to prevent the damage. However, most of the measuring devices related to humidity, harmful gas, and fine dust except temperature sensors are exposed to high concentrations of gas and dust inside pig house and are difficult to withstand for a long time. The purpose of this study is to develop an wearable based device to monitor the hazardous environment exposed to workers working in pig farms. Based on the field monitoring and previous researches, the measurement range and basic specifications of the equipment were selected, and wearable based device was designed in terms of utilization, economic efficiency, size and communication performance. Selected H₂S and NH₃ sensors showed the average error of 5.3% comparing to standard gas concentrations. The measured data can be used to manage the working environment according to the worker's location and to obtain basic data for work safety warning.

• 대한한방내과학회지
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• 제29권1호
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• pp.25-31
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• 2008

Objectives : The study was intended to investigate whether Iljoong-eum (IJE) significantly affects proliferation and growth of prostate cancer cells. Materials and Methods : In vitro, after the treatment of DU-145 and PC-3 cells with IJE, we performed Sulforhodamine B (SRB) method. In vivo, a total of 8 male nude mice subcutaneously transplanted with the PC-3 cell line were divided in 2 groups. An experimental group was given IJE orally at a dose of 4.29ml/kg per day from the 8th to 31st day following tumor injection. All mice were observed for 31 days, and sacrificed by CO2 gas asphyxiation at the end of the experiment. The mean tumor volume and body weight of both groups were compared using Student's t-tests. Results : In vitro, IJE inhibited significantly proliferation and growth of DU-145 cells and PC-3 cells. In vivo, IJE inhibited significantly proliferation and growth of PC-3 cells xenografted into athymic nude mice. Conclusions : Our data has shown that IJE is effective in suppressing the growth rate of prostate cancer cells.

• 융합신호처리학회논문지
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• 제24권2호
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• pp.82-89
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• 2023

선박 구조 특성상 격실 구조는 복잡하고 협소하여 작업 과정에서 안전사고가 빈번히 발생하고 있다. 사고의 주된 원인은 구조물 충돌, 낙하물, 독성물질 누출, 화재, 폭발, 질식 등이 존재한다. 사고 발생 시 작업자의 현장 상황을 파악하는 것이 피해를 완화하는 요소 중 하나이다. 이에 안전성을 확보하기 위해 선박 내 CCTV로 현장 상황을 모니터링하고 있으나, 기존의 방식으로는 사고를 예방하기엔 어려움이 있다. 이를 해결하기 위해 안전 기술로 위치 식별, 음성/영상 통신 기능이 탑재되는 스마트 안전모가 개발 중에 있다. 또한, 작업 구역 내 환경 정보 수집 및 저장기능을 포함한 온도, 습도, 진동, 소음, 기울기(자이로 센서), 가스 센서를 사용하여 스마트 안전모를 착용한 작업자에게 위험 상황을 알릴 수 있다. 이를 통해 스마트 안전모 및 환경 센서의 사용으로 선박 내 작업자의 안전성을 강화할 수 있을 것이다.

• 한국가금학회지
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• 제46권1호
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• pp.39-46
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• 2019

본 연구는 사료 내 첨가된 봉독이 육계의 혈청 성분, 항산화능 및 간 내 지방산 조성에 미치는 영향을 조사하기 위해 수행하였다. Ross 308 1일령 육용종 수평아리를 공시하여, 5개의 처리에 7 반복으로 반복 당 25수씩, 총 875수를 완전임의배치하여 실험을 진행하였다. 기초사료는 옥수수 및 대두박 위주의 사료를 사용하였으며, 정제 봉독을 기초사료에 $10{\mu}/kg$, $50{\mu}/kg$, $100{\mu}/kg$, $500{\mu}/kg$ 수준으로 첨가하여 5주간 급여하였다. 실험 21일차에 펜당 1수의 육계를 $CO_2$가스로 안락사시킨 뒤 혈액 샘플을 채취하여 혈액지표와 항산화능을 측정하였다. 또한, 간 샘플을 채취하여 간 내 malonaldehyde 함량과 지방산 조성을 분석하였다. 사료 내 봉독 첨가는 triglyceride와 NEFA를 제외한 나머지 혈청 성분에는 영향을 미치지 않았다. 봉독 첨가 수준이 증가할수록 간 내 지방산의 불포화 지방산(palmitoleic acid, oleic acid, 그리고 linoleic acid)은 감소하였으나(quadratic, P<0.05), 간 내 stearic acid 함량은 반대로 증가하였다. 마지막으로 간 내 MDA 함량은 봉독 첨가 수준이 증가할수록 감소하였다. 본 연구에서 육계 사료 내 봉독 첨가는 항산화능을 높이고, 지방산 대사에 영향을 미치는 것으로 조사되었다.