• International Journal of Aeronautical and Space Sciences
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• 제14권1호
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• pp.75-84
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• 2013

In this paper, the guidance law for formation flight and collision avoidance of multiple Unmanned Aerial Vehicle (UAV)s is proposed. To construct the physically comprehensible guidance law for formation flight, the virtual structure approach is used. To develop a guidance law for collision avoidance considering both other UAVs and unknown static obstacles, a geometric approach using information such as a relative position vector is utilized. Through the Lyapunov theorem, the stability of the proposed guidance law is proved. To combine guidance commands, the concept of the elastic weighting factor inspired by the elastic behavior of shape memory polymer, which tends to regain its original shape after deformation, is introduced. By using the concept of elastic weighting factor, multiple UAVs are able to cope actively with the situation of a collision between both UAVs and static obstacles during the formation flight. To verify the performance of the proposed method, numerical simulations are performed.

• 자동차안전학회지
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• 제14권3호
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• pp.60-64
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• 2022

In the automotive industry, the development of automobiles to meet safety requirements is becoming increasingly complex. This is because quality evaluation agencies in each country are continually strengthening new safety standards for vehicles. Among these various requirements, collision safety must be satisfied by controlling airbags, seat belts, etc., and can be defined as post-crash safety. Apart from this safety system, the Advanced Driver Assistance Systems (ADAS) use advanced detection sensors, GPS, communication, and video equipment to detect the hazard and notify driver before the collision. However, research to improve passenger safety in case of an accident by using the sensor of active safety represented by ADAS in the existing passive safety is limited to the level that utilizes the sudden braking level of the FCA (Forward Collision-avoidance Assist) system. Therefore, this study aims to develop logic that can improve passenger protection in case of an accident by using ADAS information and driving information secured before a collision. The proposed logic was constructed based on LSTM deep learning techniques and trained using crash test data.

• 한국자동차공학회논문집
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• 제20권1호
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• pp.106-111
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• 2012

Recently the usage of bicycle has increased steeply in Korea owing to traffic culture of well- being. In a car to bicycle accident investigation, the throw distance of bicycle is very important factor for reconstructing of the accident. The variables that influence on the throw distance of bicycle can be classified into the factors of vehicle and bicycle. Simulations and collision tests in actual car to bicycle accident were executed for obtaining throw distance of bicycle. The simulations were done by PC-$CRASH^{TM}$ and for actual crash tests sand bags were used for the behavior of bicyclist instead of dummy. Factors considered were vehicle velocity and the moving angles of bicycle, also the types of bicycle and vehicle were fairy cycle and automobile, respectively. From the results, the throw distances of a head-on tire collision of $0^{\circ}$ direction was longer than that of tire crash test of $45^{\circ}$ direction, and the throw distances of a head -on frame crash test of $90^{\circ}$ direction was longer than that of frame crash test of $45^{\circ}$ direction. In addition restitution coefficient between vehicle and bicycle was estimated as about 0.1 with based on actual crash tests. Finally the increaser vehicle velocity the longer the throw distances of bicycle, and the results of simulation were relatively good agreement to the experimental results.

• 한국ITS학회 논문지
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• 제17권2호
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• pp.128-141
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• 2018

본 논문에서는 대표적인 6대 협력형 차량 안전 시스템 대한 잠재적인 사회적 안전효과를 분석하는 방법론을 제시하고자 한다. 협력형 차량 안전시스템의 도입 및 확산을 위해서는 사회적으로 어떠한 파급효과를 가져올지에 대하여 안전 시스템 별 정량적 분석이 필요하다. 국내에서 사고유형 기반으로 분석이 이루어진 사례들이 있으나, 사고 시나리오를 기반으로 한 분석방법론을 찾아보기 어렵다. 이러한 방법론을 제시하기 위해서 우선 승용차나 승합차만을 대상으로 한 국내 사망교통사고 데이터를 기반으로 사고 시나리오를 분류한다. 다음으로 사고 시나리오를 분석하여 협력형 차량 안전 시스템에 적용 가능한 시나리오를 선정하고 결과적으로 사망 사고 빈도수를 통해 안전 시스템의 잠재적인 사회적 안전효과를 정량적으로 제시한다. 마지막으로 안전효과의 정량적 분석을 이용하여 협력형 차량 안전 시스템의 인증을 위한 대표 평가 시나리오를 제시한다.

• 대한교통학회지
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• 제29권1호
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• pp.125-134
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• 2011

보행자-차량 충돌사고 재구성을 위하여 본 논문에서는 사고 현장에서 수집이 용이한 정보들을 활용하여 차량의 충돌 속도를 정확하게 추정할 수 있는 퍼지 도구를 제시한다. 200건이 넘는 국내외 사고 및 실험 자료와 700건의 다중물체 시뮬레이션 결과에 근거하여 퍼지규칙과 소속함수들을 설정하였다. 개발한 퍼지도구는 4개의 소속함수와 2개의 논리적 규칙을 사용하여 보행자 선회 궤도 유형과 차량의 충돌 속도를 추론한다. 보행자 전도거리의 소속함수는 이와 같이 추론된 궤도 유형에 따라 달리 구성하였다. 작성된 퍼지 프로그램은 국내외 실제 사고 및 실험 데이터를 활용하여 그 결과를 검증하였으며 차량의 충돌속도에서 좋은 일치를 보여주었다. 이는 본 연구를 통하여 개발한 퍼지도구의 정확성과 유용성을 입증하는 것이다.

• 자동차안전학회지
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• 제13권3호
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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.

• 자동차안전학회지
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• 제4권1호
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• pp.12-17
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• 2012

ADAS(Advanced Driver Assistance System) which is developed for alleviating driver's load has become improved with extending it's role. Previously, ADAS offered simple function just to make driver's convenience. However, nowadays ADAS also acts as Active Safety system which is made to release and/or prevent accidents. Longitudinal control system, as one of major parts of Active Safety System, is assessed as doing direct effect on avoiding accidents. Therefore, many countries such as Europe and America has pushed longitudinal control system as a government-wide project. In this paper, it covers the result of evaluation system and vehicle evaluation for development study in FCW, ACC and AEB.

• International Journal of Automotive Technology
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• 제7권5호
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• pp.555-564
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• 2006

The aim of this paper is to contribute to the efficient design of traffic light poles involved in vehicle frontal collisions by developing a computer-based, finite-element model capable of capturing the impact characteristics. This is achieved by using the available non-linear dynamic analysis software "LS-DYNA3D", which can accurately predict the dynamic response of both the vehicle and the traffic light pole. The fiber reinforced polymer(FRP) as a new pole's material is proposed in this paper to increase energy absorption capabilities in the case of a traffic pole involved in a vehicle head-on collision. Numerical analyses are conducted to evaluate the effects of key parameters on the response of the pole embedded in soil when impacted by vehicles, including: soil type(clay and sand) and pole material type(FRP and steel). It is demonstrated from the numerical analysis that the FRP pole-soil system has favorable advantages over steel poles, where the FRP pole absorbed vehicle impact energy in a smoother behavior, which leads to smoother acceleration pulse and less deformation of the vehicle than those encountered with steel poles. Also, it was observed that clayey soil brings a slightly more resistance than sandy soil which helps reducing pole movement at ground level. Finally, FRP pole system provides more energy absorbing leading to protection during minor impacts and under service loading, and remain flexible enough to avoid influencing vehicle occupants, thus reducing fatalities and injuries resulting from the crash.

• 대한교통학회지
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• 제26권5호
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• pp.51-62
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• 2008

최근 각종 센서 및 통신기술의 발달은 다양한 교통류의 정보를 실시간으로 수집하고 관리, 제공 할 수 있는 환경을 제공하게 되었다. 본 연구에서는 이러한 실시간 모니터링 환경에서 차량추종 및 차로변경 이벤트 발생 시 안전도를 평가할 수 있는 방법론을 개발하였다. 이를 위해 이미지 트랙킹을 통해 추출된 개별차량 주행 정보와 기존 교통상충분석기법을 응용하였다. 차량 간 안전거리 개념을 반영한 RSI(Real-time Safety Index)와 첨단안전차량의 효과 및 성능평가 등에 주로 사용되는 TTC(Time-to-Collision), 모멘텀 보존의 법칙을 이용한 충돌에너지 개념을 추출된 개별차량의 주행정보에 적용하여 교통사고 위험도를 분석하였다. 본 연구에서 제시된 방법론은 향후 교통사고 분석 및 실시간 안전평가를 위한 자료수집이 가능한 검지시스템의 개발과 평가 등에 효과적으로 활용될 것으로 기대된다.

• 한국정보통신학회논문지
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• 제17권11호
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• pp.2677-2685
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• 2013

차량에서 수집된 차량 운행 데이터는 차량에서 발생한 영상 데이터 및 센싱 데이터가 그대로 기록된 것이기 때문에 외부에서 차량에서 일어나는 일을 분석하여 판단할 수 있는 객관적인 데이터로 이용할 수 있다. 본 논문에서는 차량의 움직임 및 운전자의 조작 상태를 감지하고 분석하여 실제 도로 상황에서 차량 충돌 사고가 발생했을 때, 차량의 움직임, 운전자의 각종 조작상태, 충돌 펄스 및 충돌과 관련된 신호들을 감지하고 저장하여 분석하는 사고 상황감지 시스템을 설계 및 구현하였다. 제안한 시스템에서는 충돌 직전 운전자의 반응, 차량의 조작 상태 및 물리적인 움직임에 대한 정보를 제공한다. 이렇게 수집하여 분석한 차량 운행 데이터는 충돌 사고가 발생했을 때, 사고 원인을 규명하고 공정한 사고처리에 이용할 수 있으며, 운전자의 운전 습관을 파악하여 잘못된 운전 습관의 교정 및 유류비 절감 등의 효과를 얻을 수 있다.