The purpose of this study is to develop the protection of passengers in the event of a side collision with a school bus for children. Rub-rail is installed in the United States and other countries to protect the side of school buses for children to some extent. However, in the case of Korea, there are no safety devices to protect the side of school buses for children. Therefore, the FE model was analyzed to see if there is a difference depending on whether or not Rub-rail installed on school buses in the United States is applied, and whether it affects the damage to the human body. As a result, the maximum amount of intrusion at the point of collision differs depending on whether Rub-Rail is installed. It is expected that the evaluation results of IIHS for Rub-Rail may vary depending on the degree of intrusion.

Recently, there has been an increasing demand for independent suspension systems in commercial vehicles, and various researches related to this trend are currently underway. In this study, as part of an effort to localize the independent suspension system for commercial vehicles, a preceding study was conducted to convert the existing forging process into a casting process. The structural stability of the developed product was evaluated by performing stress analysis on both forging and casting materials. In order to compensate for the low yield characteristics of the casting material, design improvements were made to lower the maximum stress level based on numerical simulations.Additionally, Lightweight design was performed, capitalizing on the inherent design flexibility offered by casting products. As a result, it was confirmed that the developed product exhibited similar stress characteristics level to the existing product, along with a weight reduction of approximately 5%.

PURPOSES : In the case of a turning maneuver at an at-grade intersection or changing the driving path, the trajectory of a vehicle with a long body, such as a large bus or an articulated bus, should be analyzed from the perspective of road design. In this study, an articulated bus was selected to analyze the off-tracking, swept path width, and lane encroach hment for vehicle turning. METHODS : In this study, four scenarios were developed for right- and U-turn situations. For the right-turn situation, cases were divided into radii of 15 m (Scenario 1) and 40 m (Scenario 2). For the U-turn situation, the cases were analyzed based on a U-turn after stopping at the stop line (Scenario 3) and without stopping at the stop line for the U-turn (Scenario 4). Each scenario was examined at 5° (Right-turn) and 10° (U-turn) angles to analyze the off-tracking, swept path width, and lane encroachment. In addition, four Global Positioning System (GPS) antennas were installed on top of the articulated bus to obtain the driving trajectory of the vehicle. GPS locational reference points were marked on the testing ground to improve positioning accuracy. RESULTS : As a result of the right-turn analysis at an intersection radius of 15 m (Scenario 1), the average off-tracking per angle was 1.04 m, the average swept path width was 3.89 m, and the lane encroachments occurred at an angle of 65° to 70°. For the right-turn analysis at an intersection radius of 40 m (Scenario 2), the average off-tracking per angle was 3.71 m, and the average swept path width was 3.31 m. Unlike the results for the 15-m radius, no lane encroachment was found. Furthermore, the averages of the off-tracking in the at-grade intersection U-turn situation were 2.65 m (Scenario 3) and 2.54 m (Scenario 4), and the average swept path width was 6.15 m. CONCLUSIONS : The required driving width when an articulated bus performs a turning maneuver at an at-grade intersection was analyzed, revealing the implications that must be considered for busway design.

In this study, the condition of the hazardous materials in the bus was monitored according to the ventilation mode of the air conditioning system during bus service. The bus was surveyed using the indoor air quality measurement method of public transportation vehicles within one year of delivery. We evaluate the CO2 and PM10, which are the controlled parameters in buses by the Ministry of Environment, and VOCs and HCHO, the non-controlled parameters. The PM10 concentration increased due to outdoor air intake; however the CO2 concentration was found to decrease. In addition, the concentration of VOCs and HCHO was found to decrease due to the forced ventilation system and the outdoor air intake. These results show that the concentration of the other materials except PM10 can be changed due to the outside air concentration and forced ventilation system. Therefore, through indoor air quality characteristics of the bus according to air condition system are intended to be used as the basis of an operation manual.

PURPOSES: The objective of this study is to propose amendments to the Act on Financial Support to introduce and operate intercity buses with wheelchair lift. METHODS : The existing Act concerning required item(Vehicle modification, Terminal modification, Operating Losses) for the introduction and operation of intercity buses with wheelchair lift is reviewed, a revision of the Act is prepared for the insufficient part. RESULTS : In order to introduce intercity buses with wheelchair lifts, vehicle modifications and terminal modifications are required. If a wheelchair user rides an intercity bus equipped with a wheelchair lift, seat losses are also generated. (The space occupied by one wheelchair is equivalent to six regular intercity bus seats or three superior bus seats.) Under the existing Act, financial support for vehicle modification is possible but financial support for terminal modification and operating losses is impossible. When proposing an intercity bus with wheelchair lift, there is evidence of financial support but there is no representation of the central and local government share ratio. Therefore, this study proposes a share ratio for the central and local government with regard to the cost of vehicle modifications. It also proposes a legal basis for financial support for terminal modifications and operating losses.

This study investigates the indoor air quality conditions of the total of 52 buses depend on seasons, time and others. We evaluated the CO₂and PM10, the controlled parameters in express buses by Ministry of Environment and VOCs and HCHO, the non-controlled parameters. The CO₂concentration during peak commute times was 38.5% in summer and 15.4% in autumn, which are higher than the normal. But, PM10 concentration was influenced by the outside air not number of passengers. The concentration of VOCs were not related with other parameters such as number of passengers, seasons, and driving time. And then, the formaldehyde concentration was not related with seasons as it showed little difference between summer and autumn.

According to industrialization and urbanization the number of increasing cars is attributable to an explosive increase of the vehicle emissions. In this study, in consideration of the population and local transportation characteristics of South Chungcheong Province the environmental and economic cost-benefit analyses are performed to evaluate whether the CNG bus conversion gives what kind of effects. Based on the analysis result the expansion and distribution plan of CNG bus is proposed for South Chungcheong Province, and the local supply policy model is also proposed considering the acquisition and management of the economic situation of CNG charging infrastructure and the small transportation companies.

PURPOSES: The purpose of this study is to develop an effectiveness analysis method of exclusive median bus lanes, which is necessary in order to improve operation efficiency of exclusive median bus lanes. METHODS : The operation characteristics of "signalized intersection including exclusive median bus lanes" and "normal signalized intersection" were investigated and the existing capacity analysis method was also reviewed to analyze the effectiveness of exclusive median bus lanes. Delay reduction of passengers using exclusive median bus lanes which can be considered as the benefit of exclusive median bus lanes and the number of people in buses were included in the proposed effectiveness analysis method. RESULTS : It was found that the proposed method expresses properly the effectiveness of exclusive median bus lanes through performing sensitivity analysis and analyzing with the real data of the number of people in buses and passenger cars. It was also found that the proposed method demonstrates the effectiveness that measure of effectiveness of signalized intersections is changed to "sec/person". CONCLUSIONS : It was concluded that the method is a proper effectiveness analysis method because it can reflect the benefit of passengers in buses.

운전자의 인적요인분석을 위한 기초자료를 제공하는 디지털 운행기록계에서는 GPS 속도, 방위각, RPM정보 등 극히 제한된 운행정보만을 기록하여 실제 운전자의 운전행태를 분석하는 데는 많은 한계가 있다. 또한, 현재 상업화가 활발히 이루어지고 있는 차량용 블랙박스는 운전자의 운전행동보다는 차량에 대한 위험사항을 기록하고 있는 방식으로서 운전자의 실제 운전행태를 분석하기에는 많은 문제점을 보이고 있다. 따라서 기존의 교통안전관련 연구들을 살펴보면 인적요인분석에 필요한 운전자의 위험운전분석이 극히 제한적으로 이루어져 있는 현실이다. 이에 본 연구에서는 사업용자동차의 위험운전유형과 각 운전유형을 결정하는 임계치를 이용하여 버스운전자의 운전행태를 분석하였다. 또한, 버스운전자에게 위험운전에 대해 단말기를 통해 실시간으로 경고정보를 자동 제공하여 실시간경고정보에 따른 효과분석을 실시하였다. 운전자들의 행태분석에 대한 해석은 차량의 가속도 센서와 회전 각속도 센서의 종방향 가속도(Ax), 횡방향 가속도(Ay), 회전 각속도(Yaw rate) 등에 대한 분석을 통해 이루어졌다.