Young Rok Kim

Revision of Representative Truck`s Weight to Power Ratio in S. Korea

PURPOSES : The purpose of this study is to revise the weight to power ratio of the representative truck in S. Korea. So far, S. Korea has been using the unit lb/hp, and the construction machines were not considered in the evaluation of the performance of trucks. METHODS : This study was performed to recommend the use of ISO system of units, and to analyze the weight to power ratios of the representative trucks in S. Korea, including the dump trucks, concrete mixer trucks, and asphalt and concrete diffusers. RESULTS: From this study, the 85 percentile value of the weight to power ratio of the trucks in S. Korea`s was found to be 103.6 kg/kw. CONCLUSIONS : The performance standard for the representative truck has to be increased upward, considering the travel pattern of the dump trucks, concrete mixers, and asphalt and concrete diffuser trucks, travel distances, narrow area (work zone) of operation, and the saving in construction budget for climbing lane. Based on this study, the weight to power ratio of the representative truck in S. Korea could possibly be revised to 100~110 kg/kW.

The Effectiveness of Traffic Safety Education to Seniors

While the number of crashes and fatalities has decreased for the last few decades, the proportion of elderly-involved crashes has continuously increased from 19.5% in 2001 to 29.6% in 2008. This paper aims to evaluate the effectiveness of traffic safety education to seniors, which has been conducted for the purpose of providing more systematic knowledge such as safety regulations and making the elderly more aware of the risks of crashes, and eventually to reduce elderly-involved crashes. First, we investigated the levels of traffic safety knowledge of the elder people who attend senior community centers and social welfare centers in Seoul and provided traffic safety education. Then, the effectiveness of traffic safety education was evaluated by using the before-and-after analysis. We set up two different groups to improve the reliability of evaluation: one for control group and the other for comparison group. The results showed that the average scores of the control group after education were significantly improved at the 95% significance level compared to the average scores before education, whereas the comparison group did not show a significant differences in the average scores before and after education except for two questions. This indicates that the levels of traffic safety knowledge of the control group have been improved through education and therefore, the safety education seem to be effective to some extent.

A Study for Influence of Sun Glare Effect on Traffic Safety at Tunnel Hood

PURPOSES : In Korea, over 70 percent of the land consists of mountainous and rolling area. Thus, tunnels continue its upward trend as road network are extended. In these circumstances, the importance of tunnel has been increased nowadays and then its safety investigation and research should be performed. This study is focus on confirming and improving the safety of tunnel. On tunnel hood, sunglare effect can irritate driver`s behavior instantly and this can result in incident. METHODS : The study of this phenomenon is rarely conducted in domestic and foreign papers, so there is no proper measure for this. This study analyzes the driving environment of the effect of sunglare effect on tunnel hood. RESULTS : Traffic accidents stem from complex set of factors. This study build the Traffic Accident Prediction Models to find out the effect of sunglare effect on tunnel`s hood. The independent variables are traffic volume, geometric design of road, length of tunnel and road side environment. Using these variables, this model estimates accident frequency on tunnel hood by Poisson regression model and Negative binomial regression model. Although Poisson regression model have more proper goodness of fit than Negative binomial regression model, Poisson regression model has overdipersion problem. So the Negative binomial regression model is used in this analysis. CONCLUSIONS : Consequently, the model shows that sunglare effect can play a role in driving safety on tunnel hood. As a result, the information of sunglare effect should be noticed ahead of tunnel hood so this can prevent drivers from being in hazard situation.