• Journal of Auto-vehicle Safety Association
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• v.13 no.4
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• pp.53-59
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• 2021

According to the Korean Traffic Accident Analysis System (TAAS), more than 200,000 traffic accidents occur every year. Also, the statistics including auto insurance companies data show 1.3 million traffic accidents. In the case of TAAS, the types of traffic accidents are simply divided into four; frontal collision, side collision, rear collision, and rollover. However, more detailed information is needed to assess for advanced driver assist systems at intersections. For example, directional information is needed, such as whether the vehicle in the car accident way in a straight or a left turn, etc. This study intends to redefine the type of accident with the more clear driving direction and path by referring to the Negligence standards used in automobile insurance accidents. The standards largely divide five categories of car-to-car/motorcycle /pedestrian/cyclist, and highway, and the each category is classified into dozens of types by status of the traffic signal, conflict situations. In order to present more various accident types for auto insurance accidents, the standards are reclassified driving direction and path of vehicles from crash situations. In results, the car-to-car accidents are classified into 33 accident types, car-to-pedestrian accidents have 19 accident types, car-to-motorcycle accidents have 38 accident types, and car-to-cyclist accidents are derived into 26 types.

• Tribology and Lubricants
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• v.11 no.3
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• pp.40-47
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• 1995

The engine oil life was examined experimentally for small size single cylinder engines. This study was conducted in the laboratory. An Eddy Current type engine dynamometer was used with a motorcycle and a cultivator engine. Physical and chemical properties of used oil was analyzed to examine the oil life. Flushed oil was used for the reference instead of the new oil. It were found that deterioration of dynamic viscosity and anti-wear property of engine oil was due to dilution by fuel not depletion of ZDTP.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.167-168
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• 2003

우리나라는 1987년 7월부터 휘발유 및 LPG 연료 사용 자동차에 배출가스 저감장치인 삼원촉매(3way catalytic converter)를 부착하였고 배출가스 측정방법도 중량규제(ｇ/km)로 하였다. 그러나 이륜자동차는 2001년부터 2행정기관에 대해서 산화촉매를 부착토록 하였으며, 오염물질 측정방법도 2000년에 이르러 정지가동시 측정하는 농도규제(%)에서 트랜지언트(transient)방법에 의한 중량규제(ｇ/km)로 강화하였다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.49-50
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• 2002

이동오염원 중 자동차 대기오염 현황을 정확히 파악하고 이에 대한 대책을 강구하기 위해서는 차종별 대기오염물질의 배출량을 정확하게 파악할 필요가 있다. 현재 자동차에 의한 배출계수, 활동도, 산정방법 등은 다양하게 진행되고 있으나, 이륜차에 의한 배출량은 연구가 미미한 상태이다. 따라서 본 연구에서는 도로이동오염원에 의한 배출량과 그중 이륜차에 의한 대기오염물질 배출량과 기여율을 추정하고자 한다. (중략)

• Proceedings of the Korea Contents Association Conference
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• 2013.05a
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• pp.209-210
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• 2013

본 연구에서는 보건복지부에서 중증 응급환자를 위한 '중증질환별 특성화 센터'로 지정된 안양의 H병원에서 오토바이 사고로 인해 응급실을 내원하여 중증외상 환자로 분류된 환자를 대상으로 보건복지부 중앙응급의료센터에서 정한 중증외상 등록체계를 바탕으로 중증도를 분석하여 손상기전과 생존의 영향을 미치는 인자에 대하여 알아보고자 한다.

• Journal of Chest Surgery
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• v.36 no.8
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• pp.627-629
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• 2003

The pneumopericardium following blunt chest trauma is exceedingly unusual. A patient was admitted to the emergency room after a motorcycle accident. Pneumopericardium and left pneumothorax were not detected on initial chest AP, but they were detected on chest computed tomograpy and resolved completely after chest tube insertion into the left pleural space.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.18 no.1
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• pp.58-63
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• 2010

Introduction : Head trauma is the main cause of death in aircraft crash. In a Michigan study of structurally survivable, fatal accidents, 80% of the fatally injured had received head trauma. We tried to develop a new helmet for passengers, and perform its efficiency test. Methods : An aircraft helmet requires an excellent protection against head trauma, lightness, and small volumes. In addition, it must be wearable, fire resistant, and non toxic when it is burning. We developed two new helmets made from silicone foam which met all theses requirements. One was thin (2.5cm), and the other was thick (6.3cm). These looked like a motorcycle helmet and had only a soft silicone as liner material without an outer hard shell. Therefore we can carry them easily inside aircrafts. The standard test for helmet is Snell's drop test. It measures the impact acceleration of head shaped metal wearing helmet during we drop it at certain heights. Impact sites were total 5 sites (front, back, right, left and top) for each helmet. All these sites were impacted twice. Results : The thickness of impact sites varied from 2.5cm to 6.3cm. The impact acceleration of 2.5cm thickness site when it was dropped from 1.0 meter was 379g. But, that of 6.3cm thickness site when it was dropped from 1.5 meter was only 163g. Unfortunately, both helmets didn't meet the Snell Standard for motorcycle helmets. Discussion : If we add suitable outer hard shell, and change its thickness and design, the efficiency will be increased. A study indicated that helmet could reduce the risk of head trauma up to 85%. We made helmet for passengers in aircraft crash for the first time. If we improve its weak points, it will decrease the frequency of head trauma in aircraft craft.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.9
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• pp.41-47
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• 1999

The scale of dendritic structure of a cast preform plays a key role in determining the mechanical properties of cast/forged products. In this study, casting experiments are carried out to reduce dendrite arm spacing (DAS) to smaller than 20 ${\mu}$m by increasing cooling rate of the mold and then to spheriodize dendritic structures by addition of alloying elements such as Zr and Ti-B. From the casting experiments, appropriate casting conditions for producing the cast preform of a motorcycle connecting rod are obtained. To obtain fine microstructures of the cast preform, mold temperature must set to be low whilst cooling rate being high. When cooling rate is 10 $^{\circ}C$/s, the size of DAS is 17.4 ${\mu}$m. And the degree of spheriodization of a grain in the cast preform is described by aspect ratio, which is defined as the ratio of major and minor radii of an elliptical grain. When 0.5% Zr and 0.24 % Ti+B are added to the molten aluminum alloy, the best aspect-ratio 0.75 is obtained. After forging the cast preform of a motorcycle connecting rod, the microstructure and mechanical properties of the cast preform are compared with those of the cast/forged product. Cast/forged products are superior in microstructure and in mechanical properties such as ultimate strength, elongation, and hardness.

• Proceedings of the Korea Information Processing Society Conference
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• 2021.11a
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• pp.1290-1293
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• 2021

Currently, blind people are experiencing a lot of inconvenience in their daily lives. In order to provide helpful service for the visually impaired, this study was carried out to make a new smart glasses that transmit information monitoring walking environment in real-time object recognition. In terms of object recognition, YOLOv4 was used as the artificial intelligence model. The objects, that should be identified during walking of the visually impaired, were selected, and the learning data was populated from them and re-learning of YOLOv4 was performed. As a result, the accuracy was average of 68% for all objects, but for essential objects (Person, Bus, Car, Traffic_light, Bicycle, Motorcycle) was measured to be 84%. In the future, it is necessary to secure the learning data in more various ways and conduct CNN learning with various parameters using darkflow rather than YOLOv4 to perform comparisons in the various ways.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.12
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• pp.1293-1303
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• 2006

This paper represents a comparison the difference between existence and nonexistence of soundproof trees for road traffic noise. Also we suggested that the simple equation has been derived using a single regression analysis for predicting levels of $Leq_{th}$ at a given distance from a road in terms of the flow rate, the mean speed of the traffic, and the percentage of the type vehicles in the existence and nonexistence of soundproof trees. We classified a vehicle into four and analyzed contribution rate to traffic volume. As a result, the order showed as followed: light vehicle>medium vehicle>heavy vehicle>motorcycle. However, the results of analyzing contribution rate with between traffic volume and traffic noise by the each type showed as followed; Motorcycle>Light vehicle>Medium vehicle>Heavy vehicle. This study showed that the most a lof of traffic volumes of the three vehicles(light vehicle, medium vehicle and motorcycle) and heavy vehicle were existed in 67 km/h and 61 km/h of car speed, respectively. The total traffic noise to the mean car speed decreased because of the inflow a lot of traffic volumes between 2016 and 2388 in the range of 67 km/h of light vehicle speed, in traffic composition of 4.75% heavy vehicles, and 1.11% motorcycle. the final result for this study showed that statistical paired t-test for between existence and nonexistence of soundproof trees was significant(p<0.05) and the difference between daytime and night in the location of the nonexistence of plant communities with the independent sample T-test was significant(p<0.05). However, the independent sample T-test for analyzing the variance of traffic noise between daytime and night was not significant(p>0.05).