• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.112-112
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• 2020

하천에서 유해화학물질 유입 사고 발생 시 수환경 피해를 최소화하기 위해 신속한 초기 대응이 필요하다. 따라서, 본 연구에서는 수환경 화학사고 대응 시스템 구축을 위해 하천 실시간 모니터링 지점에서 관측된 유해화학물질의 농도 자료를 이용하여 발생원의 유입 지점과 유입량을 역추적하는 프레임워크를 개발하였다. 본 연구에서 제시하는 프레임워크는 첫 번째로 하천 저장대 모형(Transient Storage Zone Model; TSM)과 HEC-RAS 모형을 이용하여 다양한 유량의 수리 조건에서 화학사고 시나리오를 생성하는 단계, 두번째로 생성된 시나리오의 유입 지점과 유입량에 대한 시간-농도 곡선 (BreakThrough Curve; BTC)을 21개의 곡선특징 (BTC feature)으로 추출하는 단계, 최종적으로 재귀적 특징 선택법(Recursive Feature Elimination; RFE)을 이용하여 의사결정나무 모형, 랜덤포레스트 모형, Xgboost 모형, 선형 서포트 벡터 머신, 커널 서포트 벡터 머신 그리고 Ridge 모형에 대한 모형별 주요 특징을 학습하고 성능을 비교하여 각각 유입 위치와 유입 질량 예측에 대한 최적 모형 및 특징 조합을 제시하는 단계로 구축하였다. 또한, 현장 적용성 제고를 위해 시간-농도 곡선을 2가지 경우 (Whole BTC와 Fractured BTC)로 가정하여 기계학습 모형을 학습시켜 모의결과를 비교하였다. 제시된 프레임워크의 검증을 위해서 낙동강 지류인 감천에 적용하여 모형을 구축하고 시나리오 자료 기반 검증과 Rhodamine WT를 이용한 추적자 실험자료를 이용한 검증을 수행하였다. 기계학습 모형들의 비교 검증 결과, 각 모형은 가중항 기반과 불순도 감소량 기반 특징 중요도 산출 방식에 따라 주요 특징이 상이하게 산출되었으며, 전체 시간-농도 곡선 (WBTC)과 부분 시간-농도 곡선 (FBTC)별 최적 모형도 다르게 산출되었다. 유입 위치 정확도 및 유입 질량 예측에 대한 R²는 대부분의 모형이 90% 이상의 우수한 결과를 나타냈다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.10a
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• pp.34-36
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• 2013

Despite the fact that navigation technology and educational programs were developed and maritime law has been enforced strictly, the number of maritime accidents has not dropped significantly. In order to reduce traffic accidents at sea, the preventive index for maritime accidents is designed and measured to evaluate and visualize the activities performed. The survey module is composed of preventive domains such as education, engineering, enforcement and information. The index was abstracted from the statistics of maritime accidents causes(2010~2012). It can be evaluated by using the newly developed survey modules. It was found that there is some correlation between the index value and the accident rate of maritime traffic. It is expected that this index will become another useful tool to help prevent maritime accidents.

• Journal of the Korean Institute of Gas
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• v.12 no.3
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• pp.56-63
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• 2008

We have garnered 3,593 data of gas [Natural Gas (NG) and Liquefied Petroleum Gas (LPG)] accidents reported for 16 years from 1991, and then analyzed the accidents according to their types and causes based on the classified database. According to the results the gas leak has been the most common accident followed by the explosion and then fire accidents. The most frequent accident-occurring locations for fire, explosion and leak are recognized around the valve, hose and pipeline, respectively. In addition, we have applied the Poisson analysis to predict the most-likely probabilities of fire, explosion and release in the upcoming 5 years. From this research we have assured the successive database updating will highly improve the anticipating-probability accuracy and thus it will play a key role as a significant safety-securing guideline against the gas disasters.

• Journal of Navigation and Port Research
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• v.33 no.8
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• pp.525-530
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• 2009

VTS(Vessel Traffic Service) has been established in navigational waters to improve the safety and efficiency of navigation and to prevent marine accidents which could cause a large amount of damages to the marine environment and shipping industries. There have been several reports on analyzing the causes of marine accidents happened around Korean waters of jurisdiction, and those reports contributed not only to the enlargement of waters where VTS operation was needed and but also the construction of VTS system which was necessary to provide vessels navigating in the service waters with safety-related information. However, the researches for the role of VTS in marine transportation were not still enough to increase the safety of navigation and to decrease the number of accidents. In this paper, in view of the fact that VTS operation is closely connected with the accidents, we analyzed that what parts of VTS operation are involved deeply with the causes of marine accidents in Busan Port, and then proposed a method to improve its performance most effectively.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.1
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• pp.14-26
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• 2019

For bus drivers' safe driving, a policy that analyzes the causes of the drivers' traffic accidents and then assists their safe driving is required. Therefore, the Ministry of Land, Infrastructure and Transport set up its plan to gradually expand the equipping of commercial vehicles with FCWS (Forward Collision Warning System) and LDWS(Lane Departure Warning System), from the driver-supporting ADAS(Advanced Driver Assistance Systems). However, there is not much basic research on the analysis of bus drivers' traffic accidents in Korea. As such, the time is appropriate to research what is the most necessary ADAS for bus drivers going forward to prevent bus accidents. The purpose of this research is to analyze how serious the accidents were in the different bus routes and whether the accidents were repetitive, and to give recommendations on how to support ADAS for buses, as an improvement. A model of ordered logit was used to analyze how serious the accidents were and as a result, vehicle to pedestrian accidents which directly affected individuals were statistically significant in all of the models, and violations of regulations, such as speeding, traffic signal violation and violation of safeguards for passengers, were indicated in common in several models. Therefore, the pedestrian-sensor system and automatic emergency control device for pedestrian should be installed to reduce bus accidents directly affecting persons in the future, and education for drivers and ADAS are to be offered to reduce the violations of regulations.

• Journal of the Korea Institute of Construction Safety
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• v.1 no.1
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• pp.47-56
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• 2018

In this paper, we analyze various cases of accidents caused by vehicle-mounted MEWPs(mobile elevated work platforms) which are most widely used for the high position level works, review the safety improvement measures for each of them, and propose basic data for the revision of related laws. The accidents by MEWPs were caused by the high level of works, which lead to fatal personnel accidents, so the measures for safety must be thoroughly carried out and the obligatory regulations by the related laws must be strictly observed. In this paper, we classify the cases of accidents at the workshop as 4 representative types and propose measures and remedies for them. According to the current regulations, it is possible to prepare for the accidents such as the wire rope breakage by switching to the all-chain drive method which does not have a daily use time limit instead of the wire rope drive method which is widely used at present. Also, it is suggested to add the daily use timetable to the nameplate attachment duty item according to the driving class.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.2
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• pp.160-166
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• 2016

Crew fatigue has been recognized as a major cause of maritime accidents. Systematic study on crew fatigue has a direct impact on the human factor, but the various measures being taken to prevent human error account for most of the causes of marine accidents situation are still insufficient. In this study, 128 people who have a variety of career and job types boarded the T/S Hanbada were analyzed the changes of fatigue during the 87-days a Maritime Silk Road Sailing Expedition. Crew fatigue was measured by period of time onboard classified as mental, physiological and physical changes through survey responses and individual interviews of nurses. Also, it was identified the fatigue factor through quantitative statistical analysis. As a result of repeated measures analysis of variance for the changes of fatigue in position and gender criteria in accordance with boarded period, the position-specific analysis was that Professor Rating group has appeared to feel more mental and physical fatigue than the student population. Also, the results of fatigability about the sex-specific analysis have been found that women feel more physical fatigue than men.

• Proceedings of the Safety Management and Science Conference
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• 2006.11a
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• pp.61-64
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• 2006

현대 산업사회에서 작업자들의 안전사고에 가장 많은 영향을 미치는 요인 중 하나가 피로이다. 본 연구에서는 작업자들의 산업피로를 조사 분석하여 문제점을 도출하고 이에 대한 개선방안을 제시할 수 있는 방안을 연구하고자 한다. 또한 본 연구는 모든 작업자를 대상으로 하는 것이 아니라 병원의 간호사를 작업 영역별로 소아과, 소화계내과, 일반외과, 응급실, 수술실, 중환자실로 분류하여 작업을 분석하고, 이에 따른 작업 피로 원인을 조사하여, 작업영역 업무별, 직책별, 신체부위별로 피로 영향도를 조사하고 이를 분석하고자 한다.

• Convergence Security Journal
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• v.15 no.7
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• pp.39-45
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• 2015

Industrial secrets that companies own recently protected by various act related industrial security such as Trade Secret Act, Act on Prevention of Divulgence and Protection of Industrial Technology, etc. However, despite such protection infringement and leakage accidents of industrial secrets is increasing every year. According to a survey conducted by KAITS(Korean Association for Industrial Technology Security) annual average of estimated damage by industrial secrets leakage is estimated to be "50 trillion won." This is equivalent to the amount of annual revenue of small businesses more than 4,700 units. Following this, industrial secrets leakage causes serious damages to competitiveness of nation and companies and economic. However investment and effort to the industrial secrets leakage crime is lack of level compared to the scale of damage. Actually, most companies except some major companies are lack of response action about industrial secrets leakage because of shortage of separate organization, workforce, budget for industrial secrets leakage security. This paper aims to understand the overall flow of the industrial secrets leakage crime through various taxonomy such as cause of occurrence and leakage pathway and grasp the condition of damage from industrial secrets leakage through analyzation of internal and external industrial secrets leakage crime. This is expected to be the basis for related research.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.9
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• pp.1482-1491
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• 2013

The purpose of this study was to investigate the safety accidents and physical fatigues of school foodservice employees. Out of 300 questionnaires distributed from December 1~20, 2011, 276 responded. After excluding 54 incomplete questionnaires, 222 (usage rate: 74%) were examined in the final analysis. First, our results showed that in terms of safety accidents, most received bruises (92.8%), followed by burns (73.0%), cuts and lacerated wounds (69.4%), sprains (47.7%), falls (42.8%), fractures/dislocations (31.5%) and electric shock (2.7%). Second, we found that the average degree of physical fatigue of school foodservice employees was 3.65 based on the 5-point Likert scale. Specifically, pain in the arms and wrist was rated the highest, at 4.18. Third, results showed that the factors affecting physical fatigue were 'class of school' (P<0.05), 'frequency of meal serving per day' (P<0.05), 'no. of meals served per day' (P<0.001), 'no. of meals per employee' (P<0.05) and 'warm-up exercise before starting work' (P<0.05). This means that foodservice employees serving middle schools, serving meals three times per day, serving more than 1,000 meals per day, and serving more than 111 meals per employee perceive higher levels of physical fatigue. In addition, the physical fatigue of those who perform warm-up exercises before starting work was significantly lower than those who do not perform warm-up exercises before work (P<0.05). In conclusion, the frequently occurring major safety accidents of school foodservice employees were bruises and burns. An increase in workload also leads to the increasing physical fatigue of school foodservice employees. Thus, to lower the physical fatigue of school foodservice employees, school foodservice employees should be encouraged to perform warm-up exercises before staring work and new staffing guidelines for school foodservice employees should be developed.