• Transactions of the Korean Society of Automotive Engineers
• /
• v.13 no.6
• /
• pp.135-141
• /
• 2005

Currently many safety assessment tests are conducted by crashing a vehicle against a rigid or deformable barrier. It is quite rational to evaluate crash performance of a vehicle in a barrier test in terms of vehicle stiffness and strength. However, there has been a lot of debate on whether barrier testing is a duplicate of real world crash collisions. One of the issues is car to car compatability. There are two essential subjects in compatability. One is partner-protection when crashing into another vehicle and the other is self-protection when struck by another vehicle. When considering a car to car frontal crash between a mini car and a large heavy car, it is necessary to evaluate human body stiffness of each vehicle. In this study, in order to evaluate the compatability of cars in car-to-car crashes, four tests were conducted. Test speed of each car is 48.3km/h, and the overlap of the mini and large car is $40\%$, and the overlap of the small cars is $100\%$. In all tests, only a drive dummy is used. The test results of the car to car crash test show that vehicle safety standard of mini car is not satisfied compared with large heavy car and HIC value of mini car is higher than large car. In this case observed that the relatively lower stiffness and weight of the mini car resulted in absorbing a large share of the total input energy of the system when crashed into the large heavy car.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.37 no.1
• /
• pp.129-135
• /
• 2013

There is not enough absorption space in the side of a vehicle so injuries to a passenger are higher compared to frontal impact injuries. For the protection of the passenger in the event of a side impact, vehicle regulations and new car assessment program(NCAP) are implemented all over the world. However, passive safety such as absorption technology of vehicle body itself is limited due to the narrow space of the side part. At the present time, it is well known that a side airbag including a curtain airbag is the most effective system to protect the passenger during a side impact. In this study, optimum design of the curtain airbag is carried out to reduce Head Injury Criterion(HIC) of the passenger. Based on crashworthiness simulation, an orthogonal array is selected based on the defined design variables, the response surfaces are generated from the orthogonal array and optimization is conducted with the surfaces.

• Journal of the Korean Institute of Gas
• /
• v.18 no.1
• /
• pp.68-74
• /
• 2014

In this study, to analyze the impulsive response of a helmet, a simple vibration model is presented. Based upon the experimental data and the simulation results, an equivalent one degree of freedom vibrational system is adapted, and transient impulsive responses are analysed to investigate the influence of engineering parameters such as damping, natural frequency, and impact velocity on the impulsive response of the helmet. Maximum gravitational acceleration reduces as the damping factor value increases. When the damping factor value is around 0.6 or larger, the maximum acceleration does not change. With respect to the natural frequency and the impact velocity, it increases linearly. The relationship between head injury criterion(HIC) and maximum gravitational acceleration is also presented. The scheme of this study is expected to be utilized to economize the design process of high quality helmets.

• Journal of Korean Society of Transportation
• /
• v.23 no.3 s.81
• /
• pp.49-57
• /
• 2005

This study developed a methodology for estimating the fatality reduction by introducing technical regulation on pedestrian protection in pedestrian-vehicle collisions. Modeling a probabilistic pedestrian fatality model with logistic regression approach was one of keen interests, which employed in estimating the fatality reduction. Collision speed obtained from the accident reconstruction was used in the model development. The effects of fatality reduction, in case various Head Injury Criterion (HIC) and collision speeds are applied for the regulation. were presented as the major outcome of this study. It is expected that the outcome of this study would be an invaluable tool to assist in developing various technologies and policies for pedestrian protection.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.38 no.4
• /
• pp.385-391
• /
• 2014

A wheeled armored vehicle is a military vehicle that has been developed to enhance combat capabilities and mobility for the army. The wheeled armored vehicle has a high center of gravity, and it operates on unpaved and sloped roads. Therefore, this vehicle has a high risk of rollover crashes. To design the interior of the military vehicle, the crew's safety during rollover crashes is an important factor. However, actual vehicle tests for design are extremely expensive. In this paper, nonlinear dynamic analysis is performed to simulate the rollover crashes and the passenger injury is assessed for a wheeled armored vehicle. The scope of this research is the rollover condition, FE modeling of the wheeled armored vehicle and the dummy, arrangement of dummies, assessment of passenger injuries, and simulation model for rollover crashes.

• Korean Journal of Plant Resources
• /
• v.12 no.3
• /
• pp.192-197
• /
• 1999

The contents of total lipids and their components of brown rice grain were studied for 5 colored rice cultivars, 1 aromatic rice cultivar and 1 normal rice cultivar grown in Korea. The total lipid contents ranged 2.04 to 4.69% based on total dry weight. The Tohoku #149 showed the highest content which was followed by Hansanheukmi and Sanghaehyang-hyeolna. The lowest content were observed in three cultivars, Heuknambyeo, Hyangnambyo and Dongjinbyeo which showed no difference among cultivars. The main classes of the total lipid were triglyceride, diglyceride, free sterol, free fatty acid and sterol esters in all cultivars examined. The ratio of triglyceride in total lipid was high in colored rice and aromatic rice compared to Dongjinbyeo which is normal rice cultivars, but the ratio of diglyceride was high in Dongjinbyeo. The major fatty acid compositions in the cultivars examined were linoleic acid, oleic acid and palmitic acid. There was a varietal difference in fatty acid composition, for example, erucic acid was detected in aromatic and colored rices cultivars, while none of this compound was found in Dongjinbyeo.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.15 no.5
• /
• pp.125-132
• /
• 2007

In order to provide consumers with safety informations of vehicles according to the Korean New Car Assessment Program(KNCAP), the evaluation results and the star ratings of 21 vehicles for the side impact tests have been reported since 2003. Now, the KNCAP considers changing the side impact dummy from EuroSID-1 to EuroSID-2 near future. The rib deflection of EuroSID-2 is 20-30% higher than that of EuroSID-1 because of the removal of "Flat Tops" effect. In this study, the effect of changing the side impact dummy from EuroSID-1 to EuroSID-2 in the KNCAP side impact evaluation is estimated through the previous KNCAP evaluation results. The results show that the decrease of the star ratings would be one star($\bigstar$) approximately.

• The Journal of the Korea Contents Association
• /
• v.12 no.4
• /
• pp.401-406
• /
• 2012

Shanghai Stock Exchange is the largest stock exchange of emerging markets that there were listed firms 905, listed securities 1,537, listed stocks 949, total number of listed stocks 2 trillion 2000 billion shares. There is more development that is expected to occur in the future. The purpose of this study is to find determinants of capital structure to listed manufacturing firms in Shanghai Stock Exchange using multiple regression. Conclusions of this study are summarized as follows. First, firm size is positively related to debt ratio significantly at 1% significance level.. Second, the profitability is negatively related to debt ratio significantly at 1% significance level. Third, the growth ability is positively related to debt ratio significantly at 1% significance level. fourth, cash flow, the largest shares ownership, negotiable shares ratio are negatively related to debt ratio but they are not significant statistically. The result of this study provides information for investors and can be utilized to improvement of financial structure.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.16 no.2
• /
• pp.49-57
• /
• 2008

The performance of crash cushion systems is certified through the full scale crash tests by the standard for installation and maintenance guidelines for roadside safety appurtenance. The impact severities of impacting vehicles in collision with crash cushion systems are rated by indices THIV and PHD. Crash test results are considered to study the performance of three crash cushion systems. In case of the frontal impact or the offset frontal impact, the results show that THIV values of three systems are very close to the threshold limit for the occupant protection. Also, the results show that PHD would be improper for the occupant protection performance index. In order to improve the occupant protection performance of crash cushions, ASI needs to be included in the impact severity index.

• Proceedings of the ESK Conference
• /
• 1997.10a
• /
• pp.244-245
• /
• 1997

후각장애를 가져오는 질환에는 비, 부비동 질환, 두부외상, 상기도 감염, 간질 및 노인성치매 등의 신 경게 질환, 칼만증후군과 같은 대사성 질환 등이 있으나, 현실적으로 후각장애의 정도를 측정하기가 쉽 지않고, 후각역치가 개인간에 차이가 많아 아직 연구가 미진한 상태이다. 특히 교통사고나 산업현장에서 쉽게 접할 수 있는 두부외상이나 독성화학물질 등에 의해 후각장애가 많이 나타나고 있으나 아직 보상의 기준이 없어 환자들이 어려움을 겪고 있다. 두부손상 후에 발생하는 후각장애는 병원에서도 놓치기 쉬우며, 알아내더라도 두렷한 치료방법이 없기 때문에 간과되어온 것이사실이다. 그러나, 이런 후각장애 환자들은 집안에서 가스가 새는 것을 느끼지 못하며, 화재로연기가 나더라도 알아차리지 못하고, 음식이 상해도 잘 모르므로 위험에 빠지기가 쉽고, 후각에 이상이 있으면 자연적으로미각도 감소하므로 식욕도 떨어지고, 때로는 우울증에 빠지기도하며, 주부의 경우에는 음식을 만들기가 어렵게 된다. 두부외상을 받은 전체 환자 의 약5 -10%에서 후각장애가 나타나는 것으로 알려져 있으나, 냄새가 나지만 정확히 무슨 냄새인지 이름을 대지 못하거나 어떤 냄새를 다른 냄새와 감별하지 못하는 경우까지 합하면 대개 20-30%로 생각된다. 두부 손상 후의 후각장애의 정도는 얼마나 크게다쳤는 가에 달려있지만, 조금 다치더라도 후각장애가 심한 경우도 있다.