• 한국자동차공학회논문집
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• 제7권9호
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• pp.182-194
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• 1999

Occupant injury in rear end impact is rapidly becoming one of the most aggravating traffic safety problems with high human suffering and societal costs. Although rear end impact occurs at relatively low speed , it may cause permanent disability due to neck injuries resulting from an abrupt moment, shear force , and tension/compression force at the occipital condyles. The analysis is performed for a combined occupant-eat model response, using the SAFE(Safety Analysis for occupant crash Environment) computer program. The computational results are verified by those from sled tests. A parameter study is conducted for many physical and mechanical properties. Seat design has been performed based on the design of experiment process with respect to five parameters; seat-back upholstery stiffness, torsional stiffness of the seat-back. An orthogonal array is selected from the parameter study. A good design has been found from the analysis results based on the orthogonal array. The results show that reductions of stiffness in seat-back upholstery and joint are the most effective for preventing neck injuries.

• 대한의용생체공학회:의공학회지
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• 제27권6호
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• pp.365-369
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• 2006

According to the IIHS (Insurance Institute fur Highway Safety), side impacts are made up 30% of all accidents (reported 1998). In the case of auto accidents, head and neck injuries were most common as 58%, injuries to the body's trunk equaled 32%, and injuries to the abdomen were 21%. Therefore in this study, injury of wheelchair occupant in frontal and side impact of wheelchair loaded vehicle was analyzed using computer simulation method. The occupant was restrained at the rear of wheelchair by the lap belt. The detailed fixation and restrain conditions of the wheelchair occupant are referred to SAR J2249's recommendation. We estimated HIC(Head Injury Criteria) and HNIC (Head and Neck Injury Criteria) based on measured data.

• 한국자동차공학회논문집
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• 제8권3호
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• pp.139-150
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• 2000

Although a number of neck injuries are generated, the data which quantify the kinematic response of the human head and cervical spine in low-speed rear-end automobile collisions is very limited. On this problem, just few in vitro experimental research or some experimental research using dummy on neck injury by rear-end collision was conducted, thus systematic research is requested on full scale injury mechanism. An occupant model for the response of the occupant subject to rear-end collision using commercial dynamics package DADS was developed. Developed model shows more close agreement with the experimental data compared with the MADYMO simulation results for the cases of ${\delta}V=16$ kph in sled test. For the case of ${\delta}V=8$ kph and 33.5 kph with production seat, model also shows its reliable response compared with experimental results using Hybrid III and Hybird III with RID.

• Wind and Structures
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• 제14권6호
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• pp.537-557
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• 2011

While there are a number of guidelines used throughout the world in the assessment of acceptability of tall building accelerations, none are based on systematically conducted surveys of occupant reaction to wind-induced motion. In this study, occupant response data were gathered by both a self-reporting mechanism and by interviewer-conducted surveys in control tower structures over a period of four years. These two approaches were designed in conjunction with experimental psychologists to ensure unbiased reporting. The data allowed analysis of perception thresholds and tolerability at different building frequencies and in different wind climates. The long-term nature of the studies also allowed an investigation of the causes and effects of adaptation to building motion. As the surveys were designed to allow multiple use during single storms, the effects of exposure duration were investigated. A final exit survey was conducted at the primary survey location to investigate views of the acceptability of wind-induced motion and the factors underlying these views. The findings of the field studies indicate that none of the currently used acceleration guidelines address all of the factors that contribute to occupant dissatisfaction. An alternative framework for assessing acceleration acceptability is proposed.

• 한국정밀공학회지
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• 제21권6호
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• pp.179-187
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• 2004

In this study, for a safety assessment of wheelchair occupant in frontal and side impact of wheelchair loaded vehicle, a sled impact test was perfumed. Each test was carried out total 6 times, by using Hybrid III 50th-percentile male dummy in light weight and electric wheelchair. We estimate MC(Motion Criteria), CIC(Combined Injury Criteria), HIC(Head Injury Criteria), HNIC(Head and Neck Injury Criteria) based on measured data. Through this study, we make an assessment of risk analysis of wheelchair occupant and wheelchair. Through this study, safety standard of wheelchair is to be evaluated.

• 자동차안전학회지
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• 제6권1호
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• pp.22-26
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• 2014

Fatality of accidents on curved roads where rollover accidents are likely to take place was higher than that on straight roads. We ought to investigate factors affecting injury severity of occupant in a vehicle rollover accident. From January 2011 to December 2013, we collected data about rollover motor vehicle crash accident. We surveyed occupant's injury, vehicle type, safety devices, type of rollover accident and the number of turn in accident. Of the 132 subjects, 56.1% were males, 50.8% were drivers, 48.5% fastened seat belt, and air bag deployed in 12.1%. Among injuries sustained head, chest and abdomen were major sites of severe injury(Abbreviated injury scale>2). Seat belt use, rollover type, and the number of 1/4 turn were found to have significant positive correlations with Injury Severity Score. The regression analysis herein found significance in safety belt use and the number of 1/4 turn. Seat belt use was a significant factor affecting injury severe of occupant in rollover accident.

• 한국건설관리학회논문집
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• 제19권3호
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• pp.11-22
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• 2018

건축물 화재상황에서 피난시간을 감소시키기 위한 기존의 노력들은 피난시간의 구성요소 중 피난행동시간을 감소시키는 데 집중되었다. 그러나 피난행동시간의 비율이 전체 피난시간의 1/3임에도 불구하고 이를 제외한 인지시간과 초기대응행동시간을 감소시키기 위한 고려는 부족한 실정이며, 특히 피난행동시간만을 감소시킴으로써 피난성공률을 향상시킬 수 없는 상황이 발생하게 되었다. 따라서 인지시간과 초기대응행동시간을 감소시킬 수 있는 재난정보라는 개념이 주목 받게 되었다. 본 연구는 재난정보가 재실자특성에 작용하는 과정을 분석하기 위해 피난시간의 감소 측면에서 10가지 주요 재난정보와 3가지 재실자특성 요소의 관계를 설명하는 재난정보-재실자특성 연관성을 도출하였다. 또한 노인, 지적장애인, 청각장애인과 시각장애인을 대상으로 설문조사를 통한 가상의 피난실험을 수행, 재난정보가 재실자특성에 작용하는 과정을 부족한 재실자특성을 보완하여 최저수준의 화재안전성을 확보하는 과정과 일정 수준 보유한 재실자특성을 극대화하여 화재안전성을 확보하는 과정으로 분석하였다. 본 연구를 통해 직관적인 수준에서 설명되는 기존의 재난정보-재실자특성 간의 관계에 피난시간의 감소라는 관점에서의 설명력을 더하였고, 향후 다양한 재실자 유형이 존재하는 상황에서의 재난정보 관계에 대하여 후속연구가 진행된다면 재난정보와 재실자특성을 고려하는 후속 연구에 기초적 자료를 제공할 것으로 기대된다.

• 한국화재소방학회논문지
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• 제13권3호
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• pp.35-42
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• 1999

건물 화재 시 인명안전설계의 목표는 피난에 필요한 최소한의 시간을 확보하는 것이다. 본 논문에서는 적정 피난 설계를 위하여 다음과 같은 내용을 연구하였다.-국내 사무소 건물의 거주밀도 분포를 조사 분석하였다. -고층 사무소 건물에서 대피훈련을 시행하여 예상 피난시간을 관측하였다. -피난전용 프로그램의 하나인 SIMULEX를 적용하여 컴퓨터 피난모델의 특성과 적용상의 한계를 연구하였다. -거주밀도와 파난시간과의 상관성을 분석하였다. 연구 결과 국내 사무소 건물의 거주밀도는 총 바닥면적(Gross Area)기준으로 13.14$m^2$/인 -22.69$m^2$/인이며 평균 19.72$m^2$/인 (193ft\sup 2\인)으로 조사되었다. (95% 신뢰도 기준) 또한 고층 사무소 건물의 대피훈련과 SIMULEX 모델 결과를 비교하여 피난시간에 큰 차이가 나타나 현 모델의 가정과 계산 방법에 한계가 있음을 보여주었다. 한편, 거주밀도와피난시간과의 분석 결과, 동일용도에서도 차이를 보이고 있어 용도별 거주밀도 기준 마련이 시급한 것으로 판단된다.

• 한국자동차공학회논문집
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• 제7권6호
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• pp.144-155
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• 1999

An occupant analysis code SAFE (Safety Analysis For occupant crash Environment) is utilized to simulate and improve the crash performance of an energy absorbing steering system. The safety standard FMVSS 203 is simulated and used for design evaluations . Segments and contact elliposids are utilized to model the bod blocks and the components of the steering system with SAFE. Spring-damper elements and force-deflection characteristics are utilized to model the energy absorbing components such as the plate and the polyacetal molding. The plate absorbs the impact energy through tensile deformation . Whereas, the polyacetal molding absorbs the impact energy through compression. the body block test is carried out to validate tie simulation model, and real component tests are performed to extract the force-deflection curves . After the model is validated , the parameter study is carried out to evaluate the crash performance of the energy absorbing components. A performance measure is defined for the parameter study. Using the results of the parameter study and managing the orthogonal arrays, optimum design values of energy absorbing components are determined to minize the occupant injury.

• 한국자동차공학회논문집
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• 제4권6호
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• pp.85-96
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• 1996

Most protection systems such as seat belts and airbags are not effective means for side structure. There has been significant effort in the automobile industries in seeking other protective methods, such as stiffer structure and padding on the door inner panel. Therefore, a car-to-car side impact model has been developed using ATB occupant simulation program and validated for test data of the vehicle. Compared to the existing side impact models, the developed model has a more detailed vehicle side structure representation for the more realistic impact response of the door. This model include impact bar which effectively increases the side structure stiffness without reduction of space between the occupant and the door and padding for absorbing impact energy. The established model is applied to a 4-door vehicle. The parameter study indicated that a stiffer impact bar would reduce both the acceleration-based criteria, such as thoracic trauma index: TTI(d), and deformation-based criteria, such as viscous criterion(VC). Padding on the door inner panel would reduce TTI(d) while VC gives the opposite indication in a specified thickness range. For a 4-door vehicle, the stiffness enhancement of B-pillar is more beneficial than that of A-pillar for occupant injury severity indices.