The purpose of this study is to develop an accident hazard index model in order to be used for the evaluation of regional traffic safety and to develop a driver violation index model in order to identify the primary causes of traffic accidents. The accident hazard index model was developed considering the accident rates based on population and the vehicle registration. The driver violation index model was developed considering the accident rates of each item of driver violation. Using the models developed in this study, it is identified that in the provincial level analysis the degree of the traffic safety of Chungbuk, Chungnam, and Kyungbuk Province are evaluated to be low. In the county level analysis of Kyungnam Province, the degree of the traffic safety of Yangsan, Euirung, Haman, Sachun and Tongyung County are evaluated to be low. Also, it is found that the major driver violations causing accidents in the nation are driving by unlicensed drives, improper passing, and improper railroad crossing : in Kyungnam Province, improper passing is the most driver violation.

The traffic forecast is one of the most important analysis objects in the urban transportation planning process. The results of traffic forecast are the most widely used informations and give a critical influence on the major decision makings in the transportation planning process. Thus, they should be as much accurate and credible data, and evaluated to determine whether they are enough reliable to directly use in the planning process. However, the evaluation process is usually overlooked or abbreviated with a few exceptions according to the size and character of the project. Even though a planner or engineer tries to evaluate the assignment results, he/she is usually faced with certain difficulties since there are no established criteria and methods for the accuracy evaluation. Accordingly, the main purpose of this research placed on establishing the criteria and methods for the accuracy evaluation of the assignment results. The secondary purpose was to evaluate which assignment technique produces the most accurate assignment results by applying the established evaluation criteria and methods to an actual network. The research found that the proposed evaluation methods well operated in testing the accuracy of assignment results with few limits on application. Also, the incremental assignment was found to provide the best assignment results of existing assignment techniques (Stochastic, Iterative, Incremental, Equilibrium assignment) for the Seoul city network applied.

The major concern of this paper is to investigate the properties of a stochastic equilibrium for each model system in terms of a consumer welfare measure. The primary assumption for this study is that a trip-maker would choose the trip from his origin zone which maximizes his personal welfare. This assumption, finally, leads to a singly constrained gravity model. The consumer welfare measure is derived from the concept of expected welfare of randomly sampled trip-makers. Each of the four different models considered in this paper is differentiated depending on the complexity of its model or the definition of its travel function. In this study, three different regions are chosen for the purpose of taking into account the effects of different zone-systems on the properties of a stochastic equilibrium : (i) Archerville region (5 zone) ; (ii) San Francisco Bay regions (30 zones) ; (iii) Houston, TX region (199 zones). It is concluded that almost identical, "global" consumer welfare values can be obtained in some cases of the gravity-type trip distribution models based on a stochastic equilibrium.

The objective of this research is to evaluate the pedestrian signal time involving green and flashing green times. The minimum pedestrian green indication should give time for pedestrian to start crossing safely, and the flashing green indication should give time to complete the crossing. An average pedestrian crossing speed of 1.1(m/s) was estimated by analyzing the field data which was slower than the 1.2(m/s) currently used. Furthermore, the study proposed that design speed for the flashing green time should be slow speed for considerations pedestrian safety, not the average speed. The 0.78-1.01(m/s) of pedestrian speed was estimated at the elementary school areas that indicated 0.2(m/s) slower than the other areas. The pedestrian starting time (perception/reaction time) and time headway from front to back of herd was estimated to determine minimum pedestrian green time. the pedestrian starting time was estimated to determine minimum pedestrian green time. The pedestrian starting time was ranged 2.52-4.29 seconds. The time interval between the pedestrian rows was found to be 1.25-1.86 seconds, which declines as the pedestrian rows increases, The equation to calculate the pedestrian signal, which declines as the pedestrian rows increases. The equation to calculate the pedestrian signal time is proposed using the pedestrian starting time, the time interval between the pedestrian rows, and pedestrian crossing speed given area types (commercial, business, mixed, and elementary school areas), number of both-directional pedestrians for a cycle, crosswalk length and width.

In this paper we address the issue of how an optimal sample size computation relates the level of precision required for travel demand estimations and transportation planning. We approach the problem by 1) deriving a theoretical solution, 2) developing a computational procedure (algorithm) to implement the theoretical solution, and 3) demonstrating a practical application. Ultimately, we construct a formal scheme of optimal sample size computation for use in travel data collection processe.

While bicycles are an exhaust-free and low energy consuming mode of transport, the use of them is getting decreased. The aim of this research is to find out current levels of bicycle ownership and to estimate the ownerships of the bicycles by spatial structure and social factors in the metropolitan area. The parameters which affect on the characteristics of the bicycle ownership are classified into aggregate and disaggregate categories. The ownerships of the bicycles are estimated by the multiple regression analysis using urban characteristics data and the binary logit analysis using household characteristics data. The results of this study to population, car ownership, and number of male in the household, and negatively by the population density.

Today advanced traffic management systems are required because of a high increase in traffic demand. Accordingly, the objective of this study is to take advantage of image processing systems and present image processing methods available for collection of the data on traffic characteristics, and then to investigate the possibility of traffic flow analysis by means of comparison and analysis of measured traffic flow. Data were collected at two places of Daegu city and Kyongbu expressway by using VTR. Rear view (down stream) and frontal view (up stream) methods were employed to compare and analyze traffic characteristics including traffic volume, speed, time-headway, time-occupancy, and vehicle-length, by analysis of measured traffic flow and image processing respectively. Judging from the results obtained by this study, image processing techniques are sufficient for the analysis of traffic volume, but a frame grabber equipped with high speed processor is necessary as well, with low level system judged to be sufficient for traffic volume analysis.

Drivers select approach lane according to various traffic situations as well as their destination. This behavior affects the utilization of lanes and capacity analysis at urban signalized intersections. This paper presents the concept, behavior of lane utilization, and the lane utilization factors which included in the study. Preparation of Korean Highway Capacity Manual (1992). Lane utilization is affected by various traffic and geometric factors which are roadway side friction, median friction, and number of lanes, etc. and it converges to an equal utilization as the degree of saturation (V/C ratio) increase. Lane utilization factor is suggested by the degree of saturation and the number of lanes, and it is presented in this paper.

The objective of study is to evaluate the effect of speed control hump on traffic operation and accidents. Three sites were investigated for the change of traffic accidents before and after the hump installation. Vehicle speeds approaching the hump were also analyzed. The study revealed that not only the number of traffic accidents but also the accident severity were significantly reduced by the installation of hump. Further, different types of traffic accidents with lower severity were observed after the hump installation. For the effect of speed reduction by hump, it was found that the speeds observed at 15m upstream of hump were in the range of 36~50 percent of approaching speeds which were not affected by (ie, without) the hump. Economic analysis of hump installation showed the benefit-cost ratio of 4.3 and 11.2 at two sites. Further analysis revealed that the benefit by the accident reduction exceeds the cost by speed reduction and installation capital if AADT is below 43,150 vehicles on two lane highways. It is recommended from the study that humps should be considered on two lane highways of high accident locations for excessive speeds to reduce traffic accidents and severity.

The objective of study is to evaluate design standards related to the allowable truck speeds, taper length and sign requirements together with the operating practices and economic justification for climbing lanes. Field surveys were carried out on seven climbing lanes, three on two-lane and four on four-lane freeways. Data collected are traffic volume, speed, usage rate and delay. It is found that current design criteria for determining the length of climbing lane, taper lengths, and traffic sign requirements must be upgraded. It is also recommended that regulations on the use of climbing lane be established to make it more effective. Further, economic analysis revealed that the climbing lane is economically justified for two-lane and four-lane freeway if the AADT is over 4,577 and 5,116 vehicles respectively.