• 한국도로학회논문집
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• 제18권4호
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• pp.77-82
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• 2016

PURPOSES : This paper proposes a reliability index for the safety evaluation of freeway sections. It establishes a reliability index as a safety surrogate on freeways considering speeds and speed dispersions. METHODS : We collated values of design elements including radii, curve lengths, vertical slopes (absolute values), superelevations, and vertical slopes from seven freeway sections in Korea. We also collected data about driving speeds, traffic accidents, and their deviations. We established a reliability index using these variables. RESULTS : The average radii, curve lengths, and superelevations are highly correlated with the incidence of traffic accidents. Deviations in radius and curve lengths show an especially high correlation. The reliability index, derived from speed and speed dispersions of the seven freeway sections, also correlated highly with accidents with a correlation index of 0.63. CONCLUSIONS : Since the reliability index obtained from speed and speed dispersions are highly correlated with traffic accidents, we conclude that a reliability index can be a safety surrogate on freeways considering speeds and speed dispersions together in terms of design and operational levels.

• 대한교통학회지
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• 제12권1호
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• pp.137-149
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• 1994

The objective of study is to evaluate the effect of speed control hump on traffic operation and accidents. Three sites were investigated for the change of traffic accidents before and after the hump installation. Vehicle speeds approaching the hump were also analyzed. The study revealed that not only the number of traffic accidents but also the accident severity were significantly reduced by the installation of hump. Further, different types of traffic accidents with lower severity were observed after the hump installation. For the effect of speed reduction by hump, it was found that the speeds observed at 15m upstream of hump were in the range of 36~50 percent of approaching speeds which were not affected by (ie, without) the hump. Economic analysis of hump installation showed the benefit-cost ratio of 4.3 and 11.2 at two sites. Further analysis revealed that the benefit by the accident reduction exceeds the cost by speed reduction and installation capital if AADT is below 43,150 vehicles on two lane highways. It is recommended from the study that humps should be considered on two lane highways of high accident locations for excessive speeds to reduce traffic accidents and severity.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2019년도 춘계학술대회
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• pp.18-20
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• 2019

본 논문에서는 고속 자율주행 중 차선을 이탈 하였을 때 사고를 방지하기 위해 주변 상황을 $360^{\circ}$ 카메라로 인식 후 경보를 울리는 경고 시스템을 설계하고자 한다. 자율주행 중 무리하게 차선을 바꾸려고 하거나 고속 주행 시 갑자기 나타나는 사람, 동물, 사물 등을 인지하지 못하여 사고가 발생하는 경우가 많다. 고속 자율 주행 중 차선 이탈시 카메라로 주변상황을 파악하고 차량 하부에 차선이탈 센서를 통해 경고 시스템이 울리는 자동차를 만들어 자율주행 시 일어나는 다양한 사고를 줄이고 보다 안전한 주행 시스템을 갖추고자 한다.

• Wind and Structures
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• 제6권5호
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• pp.325-346
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• 2003

High-sided road vehicles are susceptible to a sharp-edged crosswind gust, which may cause vehicle accidents such as overturning, excessive sideslip, or exaggerated rotation. This paper thus investigates the dynamic behaviour and possible accidents of high-sided road vehicles entering a sharp-edged crosswind gust with road surface roughness and vehicle suspension included. The high-sided road vehicle is modelled as a combination of several rigid bodies connected by a series of springs and dampers in both vertical and lateral directions. The random roughness of road surface is generated from power spectral density functions for various road conditions. The empirical formulae derived from wind tunnel test results are employed to determine aerodynamic forces and moments acting on the vehicle. After the governing equations of motion are established, an extensive computation work is performed to examine the effects of road surface roughness and vehicle suspension on the dynamic behaviour and vehicle accidents. It is demonstrated that for the high-sided road vehicle and wind forces specified in the computation, the accident vehicle speed of the road vehicle running on the road of average condition is relatively smaller than that running on the road of very good condition for a given crosswind gust. The vehicle suspension system should be taken into consideration, and the accident vehicle speed becomes smaller if the vehicle suspension system has softer springs and lighter dampers.

• 전기학회논문지
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• 제62권2호
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• pp.278-283
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• 2013

With the increasing power demands, size of the fault current in electrical grids is steadily increasing, and it exceeds the breaking capacity of circuit breakers. To effectively cope with these problems, a high-speed interrupter was suggested. The high-speed interrupter provides fault current with a bypass to a fault current limiter in case of accidents and consequently, fault current can be restricted. In this study, behavioral characteristics of high-speed interrupter were analyzed by accident types occurred in a distribution system. When accidents occurred, a and b contact of the high-speed interrupter were turned-off and then, turned-on. Accordingly, fault current flowed to the circuit connected to a current limiting element, and the fault current limiter restricted fault current to within a half-cycle. Nevertheless, the behavior of the high-speed interrupter was slowed down by a switching surge. As a result, fault current was confirmed to be restricted not to within the anticipated half-cycle, but to after a half-cycle. Moreover, the behavioral characteristics of the high-speed interrupter changed not only by accident types, but by behaviors of R, S, and T phases. This was due to the errors in stroke lengths of the high-speed interrupters, which resulted in a slight time discrepancy among three interrupters. In addition, the switching behaviors of the b and a contact were confirmed not to have coincided due to the switching surge; b contact behaved first and a contact followed. because of this, accuracy of stroke length and switching surges through the solenoid suction increases may be necessary to resolve.

• International Journal of Automotive Technology
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• 제5권3호
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• pp.173-180
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• 2004

An intensive study was conducted for the crash worthy structural design of the recently developed Korean High Speed Train (KHST). Two main design concepts were set up to protect both crews and passengers from serious injury in heavy collision accidents, and to reduce damage to the train itself in light collision accidents. A collision against a movable 15-ton rigid obstacle at 110 kph was selected from train accident investigations as the accident scenario for the heavy collisions. A train-to-train collision at the relative velocity of 16 kph was used for the light collision. The crashworthiness behaviors of KHST were numerically evaluated using FEM. Analysis results using 1-D collision dynamics model of the full rake consist and 3-D shell element model of the front end structure showed good crashworthy responses in a viewpoint of structural design. Occupant analyses and sled tests demonstrated that KHST performed well enough to protect occupants under the considered accident scenarios. Finally our numerical approaches were evaluated by a real scale collision test.

• 한국인터넷방송통신학회논문지
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• 제19권4호
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• pp.47-54
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• 2019

전세계적으로 기후 변화의 영향에 따른 차량 추돌 사고에 대한 위험성이 중요한 이슈로 등장하고 있다. 고속주행차량의 속도제한을 위해 다양한 형태의 속도제한 표시장치가 고려되고 있으나 현재는 대부분 고정식 속도제한 표시기를 사용하고 있다. 4계절이 뚜렷한 우리나라의 경우에는 비가 많이 오는 우기나 눈이 많이 오는 계절이나 안개가 많이 발생되는 경우에는 차량 추돌 사고를 방지하기 위한 차량 속도 감속 제한이 필요하지만 기존에 설치되어 있는 고정식 표지판으로는 사고를 미연에 방지하는 것이 어려운 실정이다. 본 연구에서는 레인 센서와 차량 와이퍼 시스템 등을 결합 시킨 기후 변화에 따른 차량 속도 제한이 가변적으로 표시되는 LED 전광판의 프로토타입 모델을 제작하였다. 내리는 비나 눈의 양에 따라 기준속도의 100%, 80%, 50%로 3단계로 가변 표시되는 속도제한 표시기는 설치되는 장소에 따라 적절한 속도를 선택 지정하여 표시할 수 있다. LED 표시장치를 이용한 시각적인 효과로 인해 운전자들이 사전에 속도를 감속하게 하여 차량 추돌 사고를 미연에 방지하는데 효과적으로 이용될 것으로 기대 된다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 춘계학술대회 논문집
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• pp.17-23
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• 2000

In Korea, the number of railroad accidents is decreasing, but the scale of railroad accidents tend to be growing large. On considering the opening of the high speed railway in 2004, the problem of railroad safety is very important. The purpose of this study is to make plans for improving railroad safety of Korea. To make this plan, we generally analyzed the future railway traffic, and reviewed annual statistics of railroad accidents trend and case studies of foreign railway accidents.

• 화약ㆍ발파
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• 제12권3호
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• pp.32-41
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• 1994

The specific characters in recent Chemical processing and industrial plants are the handling of severe limit conditions such as high pressure, high and low temperature, high speed production and transportation plant automation and appearance of many new hazardous materials in numbers and quantity. The possibilities of these characters causing the accident and environmental pollution in industrial activities become very high. This paper describes the concrete policy In prevent the explosion accident out of the many accidents which are the safety of the safety engineering.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(I)
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• pp.357-366
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• 2002

In this paper the cases on accidents/incidents and the reporting/responding procedures of high-speed rail operating countries will be reviewed and what these suggest us will be identified, and those countries' efforts to secure the prompt rescue system will be reviewed and the plan to secure the more customized rescue and rehabilitation system taking account into circumstances of our high-speed railway accident/incident will be presented.