• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2010.04a
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• pp.43-43
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• 2010

국내에 천연가스버스가 보급된 이래 5차례의 용기파열 사고가 발생하였는데 그중 2005년 8월 전주 덕진충전소에서 발생한 용기파열사고는 CNG용기의 라이너를 감싸고 있는 복합재료가 손상되어 발생한 사고로 보고되었다. 복합재료용기의 외피손상이 원인이 되어 발생한 사고사례는 해외에서 약 13건이 보고되었다. CNG용기 외피손상은 용기룰 고정하는 스트랩과 밀접한 관련이 있다. 용기고정이 불완전하면 슬립이 발생하고 이는 복합재의 손상으로 이어진다. 본 연구에서는 ISO 19078, CGA C6.4 등 국제코드의 규정을 고려하여 국내에서 제조된 Type 2, 3, 4 용기와 외국에서 생산된 Type 3 용기를 대상으로 결함깊이, 길이, 넓이에 따른 복합재료 결함 내구성시험을 수행하여 CNG용기의 내구성능을 평가하였고, 시험과 동일한 조건으로 복합재료 손상결함 조건을 컴퓨터로 전산모사하여 시험결과의 타당성과 유효성을 비교 검증하였다. 실험결과, Type 2 용기의 경우, 11,250회의 최소반복가압 회수를 충족하였으나 외피손상부와 반복가압에 따른 실제누출부위가 일치하지 않아 실험조건을 달리한 추가실험이 요구되었다. Type 3 용기의 경우에는 복합재 결함부위와 누수부위가 일치된 시험용기의 수는 67%정도로, 복합재료 용기의 수명을 저하시키는 원인으로 라이너와 외피손상이 서로 밀접한 관련이 있음을 확인하였다. Type 4 용기는 국제기준에서 요구하는 반복횟수를 만족하였고, 손상깊이 0.75mm와 1.25mm에서 반복가압회수가 60,000회 이상이 되어도 누설이 발생되지 않았다. 이는 라이너의 재질이 폴리머로서 균일한데다 탄소섬유 복합재료층 위에 유리섬유 복합재료 층이 1.5mm 정도 추가로 적층되어 있어서 3등급의 손상결함(결함깊이 1.25mm)에서도 구조 층이 전혀 손상되지 않은 것으로 판단되며, 이는 Type 2 용기의 강재라이너나 Type 3의 알루미늄 라이너와 비교하여 Type 4 용기의 폴리에틸렌 라이너의 물성이 반복성능이 탁월함을 확인할 수 있었다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.1
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• pp.29-35
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• 2018

Safety accidents are frequently occurring in day care centers in recent years. The number of types of safety accidents is bumping into, falling, burning, school bus accident, insertion... etc., and the number of children who have died due to such accidents is increasing steadily every year. Therefore, it is urgent to prevent accidents at day care centers. IoT (Internet of Things) is managed by connecting various sensors and related products from the living space to the Internet in order to prevent them from being dangerous. In particular, IoT products can be automatically controlled by smart phones and sensors anytime and anywhere, thus saving energy, time, convenience and prompt accuracy. This paper proposes a research model to prevent and respond to disasters by using SK LoRa communication network and Arduino, which are Internet access networks for building disaster management in schools, kindergartens and day care centers. And various sensors needed for building disaster management express various safety states in the building and suggests a system that can control the residential environment by transmitting and receiving data to smart phone.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.549-558
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• 2009

By the statistics of traffic safety public corporation as of Feb. 2009 year, in domestic 16,861,965 cars were registered and in this Gwangju is registered by 476,149 cars. Except Ulsan, compare to other metropolitan city, vehicles numbers are fewer. Then, as of 2009. 4. 9. by the announcement of National land and marine ministry, the operation distance of passenger cars of Gwangju metropolitan city is 40.9 km per 1 day and the most highest in the whole country. On the one hand, by the materials of traffic safety public corporation, from 2007. 1. 1 to 2007. 12. 31 for a year, traffic accidents of Korea were 211,662. By this, 6,166 people were death, 335,906 people were wounded. This mean about 17 people death and 920 people wounded per day. In Gwangju metropolitan city, last year 8,231 traffic accidents took place and 138 people were death and 13,533 people were wounded. This while government did various traffic policy to reduce traffic accidents and some degree were progressive. But still the actual circumstances is that disgrace of traffic undevelopment country can't take off. Moreover, the concern for the traffic safety of feeling of general people is very deficient. In this research, with the help of Gwangju province police station. analysed traffic accidents reality of 2009 year March and this is going to look around spring season traffic accidents prevention activities and spring season means from March to June.

• Journal of Korean Society of Transportation
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• v.29 no.3
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• pp.103-114
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• 2011

In this study, we discuss a fatal accident severity model obtained from the analysis of 112 crash sites collected since 2000, and the resulting relationship between fatal accidents and roadway geometry design. From the 720 times computer simulations for improving driving safety, we then reached the following conclusions:. First, the result of cross and frequency-analyses on the car accident sites showed that 43.7% of the accidents occurred on the curved roads, 60.7% on the vertical curve section, 57.2% on the roadways with radius of curvature of 0 to 24m, 83.9% on the roads with superelevation of 0.1 to 2.0% and 49.1% on the one-way 2-lane roads; vehicle types involved are passenger vehicles (33.0%), trucks (20.5%) and buses (14.3%) in order of frequency. The results also show that the superelevation is the most influencing factor for the fatal accidents. Second, employing the Ordered Probit Model (OPM), we developed a severity model for fatal accidents being a function of on various road conditions so as to the damages can be predicted. The proposed model possibly assists the practitioners to predict dangerous roadway segments, and to take appropriate measures in advance. Third, computer simulation runs show that providing adequate superelevation on the segment where a fatal accident occurred could reduce similar fatal accidents by at least 85%. This result indicates that the regulations specified in the Rule for Road Structure and Facility Standard (description and guidelines) should be enhanced to include more specific requirement for providing the superelevation.

• Journal of the Korean Institute of Gas
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• v.16 no.6
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• pp.73-79
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• 2012

Currently, all domestic CNG vehicles have manual cylinder valves installed. These are inconvenient for drivers in case of a gas leak accident, because drivers have to stop the vehicle operation and manually close the valve. It makes difficult condition for drivers to quickly and properly respond to such accidents. In advanced European countries, they require Automatic cylinder valve installation, which has a structure where the valve is automatically shut off when the driver turns off the ignition in case of a gas leak. If this electric valve system is introduced in Korea, the safety of CNG buses will be improved with better functionalities. In this paper, in order to solve the structural problem of difficulty for a driver to identify the operational status of individual Automatic cylinder valves, an approach was made regarding temperature increase with pressure increase during CNG filling. it was estimated that the temperature increased approximately more than $30^{\circ}C$ due to pressure difference during the filling. Therefore, it was concluded from the experimental data that the valve of the container whose temperature did not increase did not operate, resulting in filling failure.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.4
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• pp.1-14
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• 2019

In order to minimize problems related to the performance and safety of automobiles, the "Age Limit for Vehicles System" which restricts the age of buses, taxis, and trucks, was implemented in 1973. This contributed to the reduction of accidents and increase of user's service satisfaction. However, the restriction system for trucks was abolished in August 1997 as it was deemed restrictive to economic growth. It is found that one of main causes of traffic accidents such as Changwon Tunnel accident occurred in recent years, is the aging of trucks. Thus, There is a growing need for the management of the age of trucks. In this study, the time when cargo vehicles need to be managed is suggested, by analyzing the safety of cargo vehicles using vehicles inspection data.

• Journal of Auto-vehicle Safety Association
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• v.13 no.3
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• pp.78-85
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• 2021

Recently a traffic accident of heavy duty vehicles under the mandatory installation of ADAS (Advanced Driver Assistance System) is often reported in the media. Heavy duty vehicle accidents are normally occurring a high number of passenger's injury. According to report of Insurance Institute for Highway Safety, FCW (Forward Collision Warning) and AEB (Automatic Emergency Braking) were associated with a statistically significant 12% reduction in the rate of police-reportable crashes per vehicle miles traveled, and a significant 41% reduction in the rear-end crash rate of large trucks. Also many countries around the world, including Korea, are studying the effects of ADAS installation on accident reduction. Traffic accident statistics of passenger vehicle for business purpose in TMACS (Traffic safety information Management Complex System in Korea) tends to remarkably reduce the number of deaths due to the accident (2017(211), 2018(170), 2019(139)), but the number of traffic accidents (2017(8,939), 2018(9,181), 2019(10,095)) increases. In this paper, it is introduced a traffic accident case that could lead to high injury traffic accidents by being equipped with AEB in a bus. AEB reduces accidents and damage in general but malfunction of AEB could occur severe accident. Therefore, proper education is required to use AEB system, simply instead of focusing on developing and installing AEB to prevent traffic accidents. Traffic accident of AEB equipped vehicle may arise a new dispute between a driver's fault and vehicle defect. It is highly recommended to regulate an advanced event data recorder system.

• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.336-339
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• 2001

본 논문에서는 $\alpha-\beta-0$ 변환 방식을 이용한 제어방식을 모델화 하여 DSTATCOM에 적용하였다. 이러한 변환 방식을 통해서 배전 선로상에 존재하는 역상성분, 영상성분 고조파 성분 등을 나타낼 수 있으며 이에 대한 적절한 보상신호를 연산과정을 통해 생성해 낼 수 있다. 제안된 제어기의 검증을 위해 EMTDC/PSCAD를 이용한 IEEE 13 버스 배전 계통 모델링 및 유도기 부하 모델링 및 사고 모의 및 보상 시뮬레이션을 실시하였다.

• 한국IT서비스학회:학술대회논문집
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• 2009.05a
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• pp.509-512
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• 2009

최근 차량용 IT 기술이 발달함에 따라 네비게이션, 위치추적, 인터넷 접수, 원격 차량 진단, 사고감지, 긴급구난, 교통정보 등을 제공하는 서비스들이 등장하고 있다. 또한 차량의 편의성과 안정성을 추구함과 동시에 친환경 등에 대한 요구도 증가하고 있다. 그리고 최근 차량 상호간 정보의 교환이 더욱 필요해짐에 따라 차량간의 무선 통신 기능이 중요해지고 있으며 차량 내의 네트워크 기술에 대한 연구도 필요하다. 현재 차량 내 네트워크로는 CAN, LIN, MOST등의 유선으로 된 버스 시스템을 중심으로 한 차량 제어 시스템과 멀티미디어 시스템으로 크게 구분할 수 있다. 그러나 자동차 내에 장치 배선이 복잡해짐에 따라 차량의 무게 증가, 고장율의 증가, 연비 저하 등으로 이어지고 있다. 이러한 문제를 보완하기 위해 차량 내에 무선 센서 네트워크 시스템과의 통합 개발이 요구되고 있다. 본 논문에서는 빠르게 발전하고 있는 차량 내 네트워크에 대한 기술개발 동향을 분석하고, 유무선 통합형 차량 내 네트워크 응용 서비스들을 제시하고자 한다.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.237-240
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• 2003

유도전동기는 기동시 전류가 정격전류의 6배$\sim$8배에 이르기 때문에 경부하로 운전하는 경우에는 역률을 떨어뜨릴뿐만 아니라 과다한 기동전류로 인해 계통전원에 순간전압 강하를 유발시켜 선로의 전력품질(Power Quality) 저하가 심각하게 대두되고 있다. 본 논문에서는 PSCAD/EMTDC 패키지를 이용하여 IEEE에서 제시한 배전 계통 13버스 모형 모델 및 유도기 부하를 모델링하여 사고모의 및 DSTATCOM의 보상 효과를 시뮬레이션을 통하여 보였다.