• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.816-823
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• 2007

Electric car tract plays the role of supply high electric power to the electric car from the substation by using Pantograph of the electric car. It is always exposed to the external atmosphere, which results in quite substantial fluctuations in current and voltage during operation of electric car. This generates possibility of occurrence of accident at all times. Since range of wiring metallic globe installed on the catenary cannot achieve complete electrical contact, accidents are occurring due to circulating current caused by arc caused by incomplete contact due to occurrence of hairline fracture of Pantograph due to pressure or vibration of wiring. Furthermore, rapid increase in the operational current due to increase in the operational frequency of the electric car is causing erosion and short circuit of the metallic globe at the contact points. This study on arc is generated as current transmitted out of the substation courses through power line or wiring metallic globe other than the main circuit as the current is being collected at the electric car through feeder and feeder divergence device. Accordingly, since heat generated by the arc becomes the cause for generation of circulating current due to melting of metal or softening of metal due to increase in temperature accompanying increase in contact resistance, this research shall describe causes and measures against occurrence of circulation current.

• Journal of Preventive Medicine and Public Health
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• 제27권3호
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• pp.447-463
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• 1994

Despite the public health importance of injury and poisoning in terms of its high mortality and incidence, epidemiologic information to be utilized are scarce in Korea. This study was carried out in 1990 on a representative sample population (about 55,000 persons) along with the 6th National Tuberculosis Prevalence Survey in order to estimate the magnitude of injury and poisoning occurrence and to identify its epidemiologic characteristics which can be aided for establishing preventive strategy. Pre-tested and structured Questionnaire was used by trained interviewer to collect data including general information of the person, various information on the injury and poisoning during the past one year such as time and place of its occurrence, its nature and external causes, type of medical institute attended, duration of treatment and outcome of the accident occured. In analysis of the data collected incidence rates per 1000 persons by sex, age group and its nature as well as external causes, and relative frequencies were calculated. The result obtained are as followings; 1. The incidence rate per 1000 was 30 for both sexes, 39 for male and 22 for female, male being 1.8 times more frequent than female. Age adjusted incidences were not much different from the crude rates. Age group specific rate curve showed bimodal shape in both sexes, small peaks in preschool children and higher peaks in older ages. The incidence rate per 1000 people by area was highest in Jeon-bug province (57/1000) and the lowest in Daegu city(11/1000). 2. The place where the injuries occured were road in 46%, within the boundary of house in 25%, and working place in 12% The injuries and poisoning had occured more frequently during the months from March to August of the year than other months. 3. The relatively frequent injuries by its nature were contusion with intact skin surface (19%), fracture of upper limb (13%), open wound of head, neck and trunk (12%) and fracture of lower limb (11%) among males; contusion with intact skin surface (28%), sprains and strains of joints and adjacent muscle (14%), fracture of upper limb (10%) and fracture of lower limb (9%) among females. Higher incidence rate among males than females were fracture of skull (4.5 times), open wound and fractures of limbs ($2{\sim}3$ times). Age specific rate of injuries and poisoning by its nature showed increasing pattern by age in fractures of upper and lower limbs and sprains & strains of joints whereas the age group of 30's showed highest incidence in open wounds of upper limb. Fractures of radius and ulna in upper limb, fractures of tibia & fibula and ankle in lower limb were most frequent among fractures of upper and lower limbs. The frequent injuries among sprains and strains of joints and adjacent muscles were that of ankle, foot and back, and among open wound were that of head and fingers. 4. Relative frequency of injuries and poisoning by external causes showed following order : other accidents (25%), accidental falls (23%), motor vehicle accident (22%) and other road vehicle accident (14%) among males and accidental falls (37%), motor vehicle accident (24%) and other accident (18%) among females. The external causes revealing higher incidences among males than females, were other road vehicle accident (4.8 times), vehicle accident not elsewhere classifiable (4.4 times), accidental poisoning (4.4 times), accidents due to natural and environmental factors (2.8 times), and sucide & self-inflicted injuries (2.8 times). Age specific incidence by external causes for frequent injuries showed that incidence of other accident steadily increased from 10's till age 50's; motor vehicle traffic accident increased from age 20's and dropped after age 60's; on the other hand accidental fall increased strikingly by age. The most frequent external causes among motor vehicle traffic accidents was motor vehicle traffic accident involving collision with pedstrain (69%), pedal cycle accident (30%) and other road vehicle accident (71%) among other road vehicle accidents; falls on same level from slipping, tripping or standing (44%) and other falls from one level to another among accidental falls; accidents caused by machinary (32%) for male and striking against or struck accidentally by objects or person for female among other accidents. 5. Seventy nine percent of the injuries and poisonings were treated in general hospital or hospital/clinic. The duration of treatment ranged from a few days to 123 weeks; the majority(52%) took under 2 weeks, 36% for $3{\sim}8$ weeks and 4% over 21 weeks. 6. The accident resulted in full recovery of normal healthy state in 62%, residual functional defects in 21% and on process of treatment in 16%.

• 대한교통학회지
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• 제27권3호
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• pp.141-148
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• 2009

용량의 산정이 적합하지 못하다면 고속도로의 분석 및 예측에 잘못된 결론을 도출하게 된다. 도로의 용량을 일시적으로 크게 감소시키는 교통사고는 예측 불가능한 비반복정체를 발생시켜 혼잡관리가 어렵다. 따라서 본 연구는 사고발생시 속도에 따른 도로용량 파악을 목적으로 한다. 본 연구에서는 사고발생구간의 차량의 행태를 파악하여 교통류 속도에 따른 임계차두간격 산출모형과 최대통과교통량 산출모형을 구축하였다. 구축된 모형을 토대로 사고발생시의 고속도로용량감소율을 산정하였다. 그 결과 교통류의 속도가 40km/h일 때, 도로용량이 37%감소할 것으로 예측되었고, 다른 결과값은 본문에 수록하였다. 구축된 모형에 대한 검증은 제대로 수행할 수 없었지만 속도에 따른 도로용량감소율을 파악하고자 했다는데 본 연구의 의의를 두고 싶다.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2008년도 춘계학술대회 논문집
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• pp.309-312
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• 2008

In this paper, we investigated electric safety manager's PL recognition and accident occurrence of electric power facilities(power cable, transformer, circuit breaker) in electric installation for private use. The target of questionnaire survey is 450 electric installations for private use, 154 responded the questionnaire among these and it occupied 35.8%. Most of receiving voltage were 22.900kV. The questionnaire survey says that 58% of electric safety manager knew well about PL contents and 42% of them did not recognize about PL contents, About the PL application of electrical facility accidents, 82.4% of them must applied PL law, 5.8% of them did not need the PL law. Reason of PL application occupied 64% for stability of electrical facility and product, 19% for prevention of same accident. The accident of transformer occupied most and the power cable accident were much next. The questionnaire survey results, electric safety managers are interested in PL content. thev expected necessity of PL application about electrical accident strongly.

• 대한교통학회지
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• 제27권4호
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• pp.41-53
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• 2009

2003년 1월부터 2008년 6월까지 5년 6개월 동안 대전지역에서 발생한 교통사고와 같은 기간 경찰에서 단속한 통계를 근거로 통계적으로 의미가 있다고 판단된 전체분석, 중앙선침범 분석, 신호위반 분석, 음주운전 분석, 무면허운전 분석, 이륜차 분석, 보행자 분석, 교통사망자 분석 및 교통안전시설 분석, 안전홍보 및 교육 분석, 차량등록 수와 교통사고와의 관계를 SPSS12.0 통계프로그램을 이용하여 분석을 시도한 결과, 의미 있는 결과들이 산출되었다. 교통단속과 교통사고가 일정한 상관관계가 있음이 증명되어 모형이 산출되었고, 교통단속의 효과는 일정한 시간적 간격을 가지고 나타났다. 교통단속과 교통사망자와의 관계는 상관계수가 너무 낮아 통계적으로 유의하지 않은 것으로 나타나 경찰의 단속이 교통사망사고 예방에는 거의 효과가 없는 것으로 분석되었다. 이는 지금까지 추진되어온 교통안전대책의 방향전환이 시급함을 나타내는 것이어서 보다 효과적인 대안수립이 필요하다고 할 수 있다.

• Nuclear Engineering and Technology
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• 제46권6호
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• pp.803-816
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• 2014

Defense-in-depth is a fundamental safety principle for the design and operation of nuclear power plants. Despite its general appeal, defense-in-depth is not without its drawbacks, which include its potential for concealing the occurrence of hazardous states in a system, and more generally rendering the latter more opaque for its operators and managers, thus resulting in safety blind spots. This in turn translates into a shrinking of the time window available for operators to identify an unfolding hazardous condition or situation and intervene to abate it. To prevent this drawback from materializing, we propose in this work a novel safety principle termed "observability-in-depth". We characterize it as the set of provisions technical, operational, and organizational designed to enable the monitoring and identification of emerging hazardous conditions and accident pathogens in real-time and over different time-scales. Observability-in-depth also requires the monitoring of conditions of all safety barriers that implement defense-in-depth; and in so doing it supports sensemaking of identified hazardous conditions, and the understanding of potential accident sequences that might follow (how they can propagate). Observability-in-depth is thus an information-centric principle, and its importance in accident prevention is in the value of the information it provides and actions or safety interventions it spurs. We examine several "event reports" from the U.S. Nuclear Regulatory Commission database, which illustrate specific instances of violation of the observability-in-depth safety principle and the consequences that followed (e.g., unmonitored releases and loss of containments). We also revisit the Three Mile Island accident in light of the proposed principle, and identify causes and consequences of the lack of observability-in-depth related to this accident sequence. We illustrate both the benefits of adopting the observability-in-depth safety principle and the adverse consequences when this principle is violated or not implemented. This work constitutes a first step in the development of the observability-in-depth safety principle, and we hope this effort invites other researchers and safety professionals to further explore and develop this principle and its implementation.

• 조명전기설비학회논문지
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• 제22권9호
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• pp.40-46
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• 2008

본 논문에서는 자가용 전기설비에서 전기안전관리자의 PL인식과 전기설비의 사고발생에 관한 것을 조사하였다. 설문대상은 자가용 수용가 450호를 선정하였으며, 이중 154호가 설문에 응신하여 35.8[%]를 차지하였다 전기안전관리자의 58[%]는 PL에 관해 잘 알고 있었으며, 42[%]는 인식하고 있지 않았다. 이들 중 82.4[%]는 전기설비에 PL법이 적용되어야 된다고 하였으며, 5.8[%]만이 PL법의 적용이 필요 없다고 대답하였다. PL적용의 이유로는 전기설비와 제품의 안정성을 위한 것이 64[%], 동일사고의 방지가 19[%]를 차지하였다. 또한 변압기 사고가 가장 많은 부분을 차지하였으며, 케이블 사고가 그 뒤를 따랐다. 설문조사 결과로부터, 전기안전관리자들은 PL내용에 많은 관심이 있었으며, 그들은 전기사고에 관한 PL적용의 필요성을 기대하고 있었다.

• 한국방재안전학회논문집
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• 제14권3호
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• pp.39-49
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• 2021

고용노동부가 최근 발표한 '2020년 12월 말 산업재해 현황'에 따르면 산업별로 산업재해 대상이 되고 있다. 건설업별 사고사망자 수, 사고유형별 사고사망자 수, 사업장 규모별 사고사망자 수는 5~49명으로 소규모 건설현장에서 추락사고가 대부분 발생한 것으로 나타났다. 따라서 도시형 생활주택은 소규모 건설현장으로 낙상사고 발생 확률이 매우 높다. 재해 발생을 위한 가을 모의훈련은 공공부문의 대형 건설 발주기관 위주로 실시되며 소규모 건설현장에서 주택건설업체가 실시하는 것은 국내 최초다. 본 연구는 도시생활주택의 정의, 시공특성, 안전관리 실태 등을 분석·제시하고 추락사고 발생시 긴급구호절차 매뉴얼을 개발·확산하여 사망을 최소화하였다.

• Safety and Health at Work
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• 제10권2호
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• pp.205-212
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• 2019

Background: Workforce health is one of the primary and most challenging issues, particularly in industrialized countries. This article aims at modeling the major factors affecting accidents in the workplace, including general health, work-family conflict, effort-reward imbalance, and internal and external locus of control. Methods: A cross-sectional study was conducted in Esfahan Steel Company in Iran. A total of 450 participants were divided into two groups-control and case-and the questionnaires were distributed among them. Data were collected through a 7-part questionnaire. Finally, the results were analyzed using SPSS 22.0 and Amos software. Results: All the studied variables had a significant relationship with the accident proneness. In the case group, general health with a coefficient of -0.37, worke-family conflict with 0.10, effort-reward imbalance with 0.10, internal locus of control with -0.07, and external locus of control with 0.40 had a direct effect on occupational stress. Occupational stress also had a positive direct effect on accident proneness with a coefficient of 0.47. In addition, fitness indices of control group showed general health (-0.35), worke-family conflict (0.36), effort-reward imbalance (0.13), internal locus of control (-0.15), and external locus of control (0.12) have a direct effect on occupational stress. Besides, occupational stress with a coefficient of 0.09 had a direct effect on accident proneness. Conclusion: It can be concluded that although previous studies and the present study showed the effect of stress on accident and accident proneness, some hidden and external factors such as work-family conflict, effort-reward imbalance, and external locus of control that affect stress should also be considered. It helps industries face less occupational stress and, consequently, less occurrence rates of accidents.

• 항공우주정책ㆍ법학회지
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• 제19권2호
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• pp.137-162
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• 2004

항공기사고는 그 사고의 특성상 전손성, 순간성, 손해의 거액성, 지상 종속성, 국제성 등을 특정으로 하고 있다. 이러한 항공기사고는 발생하지 않아야 하겠지만 일단발생하였다 하면 대량의 인명피해와 엄청난 재산상의 손실을 가져오게 되므로 정확한 사고원인 규명을 통한 사고의 재발을 방지하기 위한 철저한 대책이 요구된다. 또한 이러한 사고조사를 통한 항공사고의 원인 규명은 항공운송인의 책임을 결정지우는 결정적 요소가 될 수 있는 점에서 독립적이고 전문적인 기관에 의해서 객관적으로 수행될 것이 요구된다. 이와 관련 우선 법적으로 문제가 되는 것은 항공기사고의 정의와 그 범위, 국제민간항공조약과 그 부속서의 효력문제, 조사과정에서의 용의자에 대한 인권침해의 가능성과 용의자의 자기부죄거부의 특권, 조사권의 관할문제와 경합문제, 재판관할, 사고조사보고서의 내용과 그 공개범위의 문제, 사고조사보고서의 소송에서의 증거로서의 채택여부와 효력문제 등으로 많은 법적문제점이 있다. 항공사고조사는 사고원인을 정확히 규명하여 사고의 재발을 방지하는 데 그 목적이 있으므로 이러한 사고조사결과의 소송에서의 이용문제는 고의 또는 과실로 인한 항공운송인의 책임유무와 그 소재파악 등 실체관계를 파악하는 최소한에 그쳐야 할 것이며 형사사법적으로 이용되어서는 아니 될 것이다. 현재 우리나라의 경우 이러한 항공사고조사를 위한 기구로 사고조사위원회가 설치되어 있지만 그 전문성과 독립성에 있어 문제가 있다고 보여진다. 이리하여 정부에서는 독립적이고 객관적으로 항공사고조사 업무를 수행할 수 있도록 현행 "항공법" 에서 항공사고조사 분야를 "항공사고조사에 관한 법률(안)" 로 분법하여 이를 보강하는 작업을 추진중에 있으나 여전히 동 위원회가 건교부 산하에 있고 그의 운영도 건설교통부령에 의하도록 함으로서 그 독립적인 지위에 문제가 있다고 본다. 따라서 새로운 법률에 의하여 탄생되게 되는 사고조사위원회는 인적 물적으로 철저하게 독립성과 전문성이 보장되는 방향으로 입법되어져야 할 것이다.