Sharif Digital Repository

Safe and efficient pedestrian movement is an important issue of concern in traffic engineering. Evaluation and identification of effective parameters in pedestrians' decision-making process when crossing a street can be beneficial in improving their safety. In this report, two streets in Tehran, Iran were selected to study the pedestrians' crossing. The data from the video films at these locations were used to fit the logit and nested logit models. The results indicate that factors such as arrival time of first nearside vehicle to crosswalk, headway between first and second vehicle approaching the crosswalk, vehicles platoon size and their approaching speed in each lane, pedestrians' age,... 

This paper introduces a new procedure to forecast the future O/D demand. It is a hybrid of logit and Fratar model. The hybrid model has the long run, policy sensitive, characteristic of a logit model, calibrated at sector-level with little/no zero O/D cells. This feature, joint with a Fratar-type operation at zonal level within a sector, gives a better performance to this model than either of the two types of the models alone. The performance of the hybrid model is contrasted with a neural network model, and shows encouraging results in a real case  

The use of cell phone is a significant source of driver distraction. Phone use while driving can impair a number of factors critical for safe driving which can cause serious traffic safety problems. The objective of this paper was to investigate the frequency of using cell phones while driving in Iran's roads through an observational survey with a random sample of drivers, to recognize contributing factors to cell phone usage and to understand the magnitude of the problem. A total of 1794 observations were collected from 12 sites at controlled intersections, entrance and exit points of highways. The cell phone use rate among drivers (talking or texting) was estimated at 10% which is... 

Efficacious transportation, as prerequisites of sustainable development of rural areas, should receive pertinent attention. This needs more attention in developing countries as nearly half of population in these countries reside in rural areas. However, still little is known about the activity and travel characteristics of rural residents. This study focuses on activity-location (Ac-Lo) patterns of rural residents in Iran. An interview of place-based questionnaire was designed and data about activity-travel characteristics of rural residents was collected. In total, 663 respondents were used for analyzing out-of-home Ac-Lo patterns. Based on a descriptive analysis of Ac-Lo characteristics of... 

The use of cell phone is a significant source of driver distraction. Phone use while driving can impair a number of factors critical for safe driving which can cause serious traffic safety problems. The objective of this paper was to investigate the frequency of using cell phones while driving in Iran's roads through an observational survey with a random sample of drivers, to recognize contributing factors to cell phone usage and to understand the magnitude of the problem. A total of 1794 observations were collected from 12 sites at controlled intersections, entrance and exit points of highways. The cell phone use rate among drivers (talking or texting) was estimated at 10% which is... 

This study is an effort to quantify potential cost savings of children's walking, as a form of active travel to school. The data were collected in Tehran, from a cross-sectional cohort of more than 4700 high school and middle school students. This study looks at a wide range of policy sensitive variables, such as safety and distance to school in various scenarios. The findings indicate if the safety concerns of parents associated with their children walking to school are alleviated, the direct and indirect annual costs of obesity decreases by US$719 per student. Further, a 1% decrease in the distance from home to school diminishes the annual per capita health costs associated with obesity by... 

This study is an effort to quantify potential cost savings of children's walking, as a form of active travel to school. The data were collected in Tehran, from a cross-sectional cohort of more than 4700 high school and middle school students. This study looks at a wide range of policy sensitive variables, such as safety and distance to school in various scenarios. The findings indicate if the safety concerns of parents associated with their children walking to school are alleviated, the direct and indirect annual costs of obesity decreases by US$719 per student. Further, a 1% decrease in the distance from home to school diminishes the annual per capita health costs associated with obesity by... 

Performing maneuvers such as braking and lane changing can hinder the occurrence of a crash. The driver tends to escape from the crash occurrence or reduce its severity by doing the maneuver, so finding the factors affecting this type of maneuver can help the driver to react better. This work aims to discover the effect of distraction-related factors on the performance of a crash avoidance maneuver. In order to pave the way for a more thorough comprehension of this matter, variables related to the characteristics of the driver, road, crash, vehicle, and environmental properties are also considered in the analysis. The used data is based on General Estimate System 2010 dataset, a dataset... 

This study provides a comprehensive literature review to summarize all contributing factors and the logit-based models that were used to predict the severity of crashes. Using the General Estimates Systems (GES) dataset, as a subset and a branch of the National Automotive Sampling System in the US, a Generalized Ordered Logit (GLM) model is developed to predict the crash severity. The developed severity model detects the most important parameters based on characteristics of the driver, the environment, the vehicle, the road, and the type of crash. This study aims to take a more in-depth look into the distraction-related factors as one of the most important groups of contributing factors to... 

Improving the service quality of public transport is necessary to maintain the loyalty of current users and attract new travelers. Past studies show that users’ preferences for transit service quality are heterogeneous, but recognizing the factors describing this heterogeneity has not been investigated in depth. This paper aims to evaluate the sources of heterogeneity in passengers’ preferences for service attributes of bus transit regarding the regular bus system in the city of Tehran. Four attributes of bus travel, including in-vehicle travel time, fare, vehicle crowding, and headway, were considered. Stated preference (SP) data of 360 commuters with work purpose was collected through... 

This paper examines the role of transportation demand management (TDM) policies on commuters' mode choice in the city of Tehran. The analysis is based on the results of a stated preferences survey developed through the design of experiments approach. Five policies covering increasing parking cost, increasing fuel cost, cordon pricing, transit time reduction, and transit access improvement are assessed in order to study their impact on commuters' consideration of six modes of transportation to travel to work. A multinomial logit model was developed for the 366 commuters who regularly commute to their workplace in the center of the city. In addition to a number of commuting and contextual... 

Truck accidents are an issue of concern due to their severity. Logit modeling and Neural Network modeling are performed to investigate factors such as vehicle, roadway, environment and driver characteristics that can potentially contribute to the severity of truck accidents. The objective of this study is to present models that can predict the severity of truck accidents and to identify the important factors causing these accidents. Comparison between neural networks and logit modeling are made using vehicle crash data on two-lane rural highways in Iran. A variety of variables related to roadways, vehicles, environment and drivers, such as, driver fatigue, head-on collision and lack of... 

Making efficient use of transportation infrastructure has always been a concern. Traveler information provisions (TIPs) assist commuters in making better travel decisions and therefore lead to increased mobility and more efficient travel. The ongoing economic crisis and shrinking public funding have made the public-private partnership (PPP) an attractive instrument for promoting TIP. Such initiatives have been much discussed in developed countries. The use of PPP to fund public projects in developing countries, however, is in its infancy, and the related issues do not receive adequate attention in the literature. In this study, PPP opportunities in TIP were assessed in the case of a city in...