• 한국자동차공학회논문집
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• 제23권4호
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• pp.420-427
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• 2015

This paper statistically reviewed for the USNCAP frontal crash test results carried out by NHTSA. Vehicle samples were selected on total 20 vehicles which were included on 15 vehicles for MPV&SUV and 5 Pickup. The results was summarized as followings. The performance for the driver was better than the passenger's in the average sense. There exist distinctions between the driver and the passenger on the USNCAP front test procedure, for example dummy size, seating position and airbag style. Therefore these differences originated in the statistical results. Main effect was Neck injury for crash performance on both dummies on the average value. Root cause of neck injury was different for each dummy, ie, the driver caused from Nte & Ntf, but the passenger did absolutely Nte mode. Reliability evaluated from the standard deviation was highly dependent upon chest injury on the driver and neck injury on the passenger. Restraint system was also summarized.

• 자동차안전학회지
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• 제9권2호
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• pp.20-25
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• 2017

KNCAP is a program to evaluate the automobile safety, providing consumer vehicle safety assessment results. The safety evaluation tests are Frontal Impact, Offset Frontal Crash, Side Crash, Side Pole Crash, Rear Impact. This is the study of the offset frontal impact safety evaluation. Currently, IIHS is performing a small overlap test. NHTSA plans to implement the oblique moving deformable barrier test. Euro-NCAP plans to implement a mobile frontal impact test. Simulation is used to compare occupant behavior and injury. We have investigated whether the introduction of the test at KNCAP is necessary. The dummy model used in the simulation was the 50th percentile male Hybrid III dummy.

• 한국통신학회논문지
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• 제38C권3호
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• pp.227-232
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• 2013

ITS 기술의 발전으로 인해 교통 분야에 관련한 서비스들이 제시되고 있다. 그리고 IEEE WG802.11과 P1609에서 추진하고 있는 WAVE가 차량 간 통신 표준으로 제정되고 있다. WAVE는 빠른 연결과정을 가지며 이동성 측면에서 우수한 특성을 나타낸다. 또한 국제적으로 차량 간 통신을 이용한 국가 프로젝트 및 서비스가 제안되고 있으며, 특히 미국 도로교통안전국에서 진행 중인 VSC-A 프로젝트에 다수의 차량 제조사가 참여하고 있고 차량 간 통신을 이용한 안전 서비스 및 측위 기술들이 제안되고 있다. 이러한 안전 서비스에 대한 모델 및 성능을 위한 차량 간 통신 성능에 대한 규격을 분석하고 제시해야 할 필요성이 있다. 따라서, 본 논문에서는 차량 간 통신을 이용한 추월보조 안전 서비스에 대한 시나리오 및 모델을 제안한다. 이를 이용하여 WAVE 환경 하에서의 네트워크 시뮬레이션을 수행하여 통신 성능을 평가하였다. 향후 차량 간 통신을 이용한 추월보조 서비스의 실차 적용을 위해 고려해야 할 요소인 채널별 전송거리 및 지연시간에 대한 결과를 결론에서 제시하였다.

• 자동차안전학회지
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• 제8권4호
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• pp.12-17
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• 2016

NHTSA (National Highway Traffic Safety Administration) has offered consumers the vehicle safety information on their car since 1978. NHTSA believes that they contribute auto makers to develop safer vehicle for customers, which will result in even lower numbers of deaths and injuries resulting from motor vehicle crashes. NHTSA has been studied why people are still dying in frontal test despite of the use of many restraints system and they understand that current test does not reflect real world crash data such as oblique and corner impact test. As a result, NHTSA announced that a new test method will be introduced to use of enhanced biofidelic dummy and new crash avoidance technology evaluation from 2019. New and refined injury criteria will be applied to Head / Neck / Chest / Lower Leg. BrIC(Brain Injury Criterion)value in NHTSA test results using THOR dummy from 2014 to 2015 was average 0.91 and 1.24 in driver and passenger dummies. IIHS 64kph SOF test is the most likely to new frontal oblique test in an aspect of offset impact which is being studied by NHTSA. In this paper, we focused on head injury, especially brain injury - BrIC and conducted IIHS 64kph SOF (Small Offset Front) test with Hybrid III dummy to evaluate the injury for BrIC. Based on the test results, these data can be predicted BrIC level and US NCAP rating with current vehicle.

• 한국자동차공학회논문집
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• 제20권5호
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• pp.81-87
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• 2012

New car assessment program (NCAP) originated from USNCAP in 1979 has been implemented in several countries or markets, for instance USA, Europe, Korea, Japan, China and Australia. NCAP has contributed greatly to reduce accidental tolls. But recently, NCAP performance has no distinction between cars because manufacturer have been continuously developed to improve NCAP performance. Therefore, NHTSA announced new USNCAP protocol becoming effective from MY2011. NHTSA had carried out many NCAP tests based on the new test protocol and announced these test results. In this paper, USNCAP test results were reviewed by statistical method. This review was focused on passenger cars and frontal crash test results in order to investigate effect of changes in new NCAP protocol. There are two key changes, one is sited female dummy in passenger position, the other is enlarged to 4 scoring body regions in each dummy. Results of this review were summarized as followings. Performance in Passenger (12.5%) is lower than Driver's (50%) for number of 5 star vehicle. Neck injury criterion is dominant to NCAP star rating for both dummies in the mean sense. For standard deviation, chest deflection is showed largest value in driver dummy but neck injury criterion is showed for passenger's. DKAB and PKAB were equipped 28.1% and 6.2%, respectively. Consequently, the countermeasure for new USNCAP frontal crash test is essential to control well dummy kinematics with some safety features including KAB to reduce neck injuries.

• 한국자동차공학회논문집
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• 제21권2호
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• pp.104-113
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• 2013

New USNCAP has been carried out by NHTSA including front and side crash from MY2011. In this paper, test results for USNCAP Side crash were reviewed by statistical analysis. This review focused on side crash test results to investigate the effect of changes from new USNCAP side crash test protocol among 30 passenger cars. These results were summarized as followings. Total number of 5 star vehicles on the front seat dummy (16 vehicles, 53.3%) was slightly smaller than the rear seat's (17 vehicles, 56.7%) in MDB test. For the ES-2re dummy, chest injury, ie maximum rib deflection contributed to 66% in the mean value of $P_{joint}$. Pelvis injury was highly dependent upon performance up to 87% in the SID-IIs dummy cited on the rear seat in average $P_{joint}$. For Pole test, pelvis injury made contribution to the average performance to 83%. For standard deviation, it showed the largest value in the same body region as the mean value for each dummy. Overall front seat performance showed 14 vehicles, 44.6% with 5 star vehicles less than each MDB or Pole test result. This result showed that performances in MDB test were different pattern to Pole test on driver position. Number of 5star vehicles for overall side NCAP performance are 18 passenger cars (60%). Curtain airbag and driver thorax airbag were equipped in all test vehicles. One vehicle is equipped with thorax airbag in the rear seat. Results from two side tests considered as reliability problem, ie the cause for large standard deviation in side crash test. Consequently, the countermeasure for new USNCAP side crash test is essential to design the effective side structures for side collision and to control well dummy kinematics with curtain and thorax airbag in order to reduce chest and pelvis injuries.

• 한국자동차공학회논문집
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• 제19권6호
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• pp.30-36
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• 2011

The current test methods are insufficient to evaluate and ensure the safety and reliability of vehicle system for all possible dynamic situation including the worst case such as rollover, spin-out and so on. Although the known NHTSA Sine with dwell steering maneuvers are applied for the vehicle performance assessment, they aren't enough to estimate other possible worst case scenarios. Therefore, it is crucial for us to verify the various worst cases including the existing severe steering maneuvers. This paper includes useful worst case based upon the existing worst case scenarios mentioned above and worst case evaluation for vehicle dynamic controller in simulation basis and UCC HILS. The only human steering angle is selected as a design parameter here and optimized to maximize the index function to be expressed in terms of both yaw rate and side slip angle. The obtained scenarios were enough to generate the worst case to meet NHTSA worst case definition. It has been concluded that the new procedure in this paper is adequate to create other feasible worst case scenarios for a vehicle dynamic control system.

• 한국자동차공학회논문집
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• 제16권6호
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• pp.1-9
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• 2008

The current test methods are insufficient to evaluate and ensure the safety and reliability of vehicle system for all possible dynamic situation including the worst case such as rollover, spin-out and so on. Although the known NHTSA J-turn and Fish-hook steering maneuvers are applied for the vehicle performance assessment, they aren't enough to estimate other possible worst case scenarios. Therefore, it is crucial for us to verify the various worst cases including the existing severe steering maneuvers. This paper includes the procedure to search for other useful worst case based upon the existing worst case scenarios mentioned above and its application in simulation basis. The only human steering angle is selected as a design parameter here and optimized to maximize the index function to be expressed in terms of either roll angle or yaw rate. The obtained scenarios were enough to generate the worst case to meet NHTSA worst case definition (ex.2-inch wheel lift). Additionally, as an application, the worst case steering maneuver is acquired for the vehicle to operate with a simple ESP system. It has been concluded that the new procedure in this paper is adequate to create other feasible worst case scenarios for a vehicle system both with an intelligent safety control system and without it.

• 한국산업정보학회논문지
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• 제26권5호
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• pp.79-94
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• 2021

소셜 미디어상의 부정적 구전에 대한 기업의 공급사슬 리스크의 중요성과 심각성에도 불구하고 관련된 연구는 미흡한 실정이다. 이에 본 연구는 제품의 부정적 구전이 소셜 미디어를 통해 어떻게 유통되는지, 부정적 구전의 유통과 확산에 영향을 주는 주체의 특징은 무엇인지를 사회적 교환이론에 기초하여 분석하였다. 이를 위해 트위터를 이용해 미국도로교통안전국(NHTSA)에서 4개 자동차 기업의 자동차 리콜 정보를 수집하였다. 최초 트위터(Seed tweet)를 바탕으로 부정적 구전의 유통과 확산을 살펴보기 위한 RT(Re-tweet) 네트워크를 구조를 분석하여 부정적 구전 네트워크의 특징을 파악하고, 초기 유포자의 특성이 부정적 구전 확산에 미치는 영향을 분석하였다. 그 결과 부정적 구전은 다수 이용자와 연결된 허브 이용자를 중심으로 확산하는 스몰월드 네트워크 구조임을 확인하였으며, 초기 유포자의 영향력이 크고 상호호혜성이 높을수록 부정적 구전 확산의 속도와 규모가 유의미하게 증가함을 발견하였다.