TRAFFIC MANAGEMENT STUDIES
Year:2010 | Volume:5 | Issue:17|Papers Count:8

The present paper aims to determine the role of road police in the management of road accidents’ scenes in order to identify and explain factors which can help decrease property damage and life injuries. After the importance of the management of road accidents and its effect on decreasing property damage and life injuries has been examined, the management of road accidents’ scenes has been discussed. The results indicate that the management of road accidents’ scenes by police road experts, while preventing secondary accidents, facilitates providing help to those affected by the accident; hence decreasing property damage and life injuries.

2Two-lane intermunicipal highways serve two functions in the highway network: mobility and accessibility. To estimate the level of service on two-lane, two-way highways two performance measures are used: Percent Time Spent Following (PTSF) and Average Travel Speed (ATS). Due to the difficulty of measuring PTSF in the field, Highway Capacity Manual (HCM2000) suggests a surrogate measure to estimate the PTSF in the field, that is, the percentage of vehicles traveling with headways of less than three seconds. The present research tries to evaluate validity of this surrogate measure in Iran. For this purpose, traffic flow was analyzed in three intermunicipal two-lane highways with inclusive counter. By using the counter data in these roads, the percentage of vehicles with headways of less than three seconds in various intervals is measured, and then using IHSDM software, traffic flow and geometric qualifications of routes in each road are simulated. The results show that values of PTSF from simulating is very close to surrogate measure, namely percentage of vehicles with headways of less than three seconds. Paying attention to traffic and geometric qualifications in Iran's roads, this research shows that surrogate measure may be used for measuring PTSF.

ITS system architecture includes creating coordination among smart transportation systems and equipment in a framework and in an integrated manner, in such a way that these systems work as a united whole in order to reduce traffic problems. In this paper, a new method to achieve a logical model for ITS architecture in Tehran metropolis is presented for the first time. Based on this method, a model for Tehran’s ITS logical architecture is developed. For this purpose, the architectures of leading countries in this regard such as US, European countries, Japan, and Canada were studied first. Since the United States is the pioneer country in ITS architecture and other countries have developed their ITS architectures based on the experiences of the United States, ITS architecture of US is used as the standard model in this paper. First, the draft of ITS logical architecture for Tehran metropolis was prepared based on the needs and the available sources. Then, this draft was revised using the opinions of twenty ITS experts who filled out two questionnaires. In these questionnaires, the experts were asked to identify the relationships among different processes and the relationships between these processes and external factors. In this way, the ITS logical architecture of Tehran metropolis was shown by plotting DFD diagram.

4This research is about trucks and their role in road accidents in Haraz road, and how to decrease such accidents. The present statistics indicate that HGVs are among the major causes of accidents in this road, but no scientific research is carried out on that. This research is a survey one, and the statistical population consists of police officers, traffic experts, and HGV drivers. The results, while confirming the research hypotheses, show that the driver’s age, his driving ability, and the kind of HGV affect road accidents. The existence of mines along the Haraz road, and the drivers’ driving hours also affect road accidents. To control the traffic and decrease HGV accidents, it is suggested to limit the driver’s age and the kind of trucks using the Haraz road, Widen and expand the road, modify the lightening system and signs, and to give time recording notebooks to drivers.

Besides human, road and environment, vehicle is one of influencing factors on driving offenses. Therefore, the main purpose of this research is to investigate the relationship between driving offenses and the vehicle type and model. The research method is a survey one, and the statistical population is all the individuals above 18 who have a driving licence and a private car. 389 drivers were selected by means of random multi-stage sampling. The measurement instrument is a questionnaire, the validity and the reliability of which was measured by content validity and retest method, respectively. Descriptive research findings point out that the driving offence is high among the drivers, and analytical results show that there is no significant relationship between vehicle type and driving offenses, but there is a significant and direct relationship between the vehicle models to driving offenses.

6As a result of daily increase in traveling, the necessity of planning the current resources and allocating new resources in all sections, especially in the management of road transportation, which, compared to all the other sections, has the greatest share in the passenger transportation, becomes important. In addition, regarding the management of the current supplies and the allocation of the future resources, predicting the number of passengers is of high priority. As a result, the economists and the transportation planners have long been keen to estimate prediction models of passengers' traveling scheme. Specialists in the fields of mathematics, statistics and computer have been trying to get to a simple and effective model for the precise anticipation of the number of passengers in the regional, national, or international scale. Estimating the demand for transportation is one of the most important factors in the design, planning, and management of transportation. The first step to design an effective and dynamic transportation system is to present a comprehensive planning composed of short-term, mid-term, and long-term periods. Therefore, in this paper an effort is made to have an overview and analysis on the observed studies in the field of demand estimation and the present distinct models of transportation distribution.

Providing accurate and up-to-date information on traffic of various vehicles in the road network helps the appropriate optimization and development of road transportation system considerably. Traditionally, different techniques, including field observation and statistical data recording, have been used to gather information on counting traffic in different roads. The aim of this paper is to determine the optimal method and equipment for traffic counting regarding environmental conditions, cost, and type of the road in Iran. To do so, common methods of traffic counting in Iran are first examined, and then automatic revelation equipment used in the national transportation system and their application are evaluated. Next, advantages and disadvantages of traffic counting equipment regarding condition of road network are analyzed, so that optimal application of such equipments is specified. Finally, the most suitable electronic equipment in traffic counting for Iran transportation network are classified and recommended based on various conditions and type of the road.