هومن شاداب مهر

Applying of two systems Light Rail Transit and Bus Rapid Transit as skeleton of public transport has been defined in Mashhad city. There are problems in the line routes of the system including about 50 percent coverage with each other along their routes that this problem reduces the system's coverage. This research is done with the aim of re-designing of the mentioned routes with a view to maximizing system access. Research method is both qualitative and quantitative and it is applied research. To reform the public transport skeleton routes a mathematical modeling approach is applied using ant colony algorithm. Then combined access index using Hansen method has been calculated divided to 253 traffic zones and in two different cases, system status quo and the system proposed by research. The population access, the places of employment and attractive land uses were have noticed on calculating the mentioned index. The research data were obtained from database of comprehensive transportation study of Mashhad which was update at 2013 using documentary study. Improved routes of public transit skeleton have been defined as the results of this research that they have no coverage with each other so the system coverage is increased while their overall length is less than the approved routes. Also the access index significantly increased in case of modified system compare with the primary one. Given that the existing public transit skeleton system has been designed with methods based on movement, the results of this research reveals differences between the methods based on movement and access in case of designing of public transport.

Today, transport planning is one of the important aspects of urban planning. In this regard, enhancement of the public transport systems and guiding the urban travels towards these systems has found a crucial role in traffic improvement, preventing capital waste and reaching to the sustainable cities. In Mashhad, two systems, namely Light Rail Transit (LRT) and Bus Rapid Transit (BRT) are defined as the main public transport systems. This research has down with the aim of effect explain of city detailed design texture streets downtown road widening on the process of public transport route designing. It should be noted that the mean of widening is not the rampant road widening but it is just road widening according to approved urban detailed designs. Theoretical foundations of research is theory of urban sustainability. The research method is descriptive-analytic. Research data is obtained from data bank of Mashhad transportation comprehensive studies by documentary study. The most part of zoning in the city of Mashhad mean divided the city to 253 traffic zones has used in order to increase the accuracy of study. The routes of the main public transport lines have re-designed using ant colony algorithm. The algorithm objective function includes variables of population, employment and the surface of trip attractive land uses and the main limitation have been defined as width of streets in two case, present situation and widening streets. So, two reform options of mass public transport systems have been produced. Then, the access index has been measured based on Hansen relation in case of two mentioned alternatives. The research hypothesis testing showed that the access index in case of alternative which achieved road widening is significantly higher than the other alternative. The research results explain importance of city detailed design road widening in view point of improving main public transport routes and increase their efficiency. According to traffic problems of central business districts of mega cities and the consequences of this include air pollution and etc. it is necessary to adopt policies to deal with these problems. One of these policies is transferring trips from private cars to public transportation which requires efficient, reliable transportation. Based on previous studies, the most important performance indicator for public transportation systems is the level of access to such systems. Increasing the level of access to the main public transportation network which will be achieved in the event of implementation of the expected road widening in the city center's detailed plan can increase the use of public transport and consequently use less than personal vehicles. So, though, on the basics of planning sustainable cities, road widening is not a good way to overcome traffic problems but such modifications appear to be necessary in the minimum amount that would allow the design and implementation of a convenient and efficient public transport network. The result of this study proved the above hypothesis. This results reveal the importance of adherence to the results of urban detailed studies, including the development of urban road networks.

Every year, a part of the national capital of the country is lost due to the disorders of traffic. An important part of the traffic disorders is caused by the improper behavior of some users of urban transport system. Such a situation is contrary to the principles of smart growth and urban sustainability. The study of traffic conflicts as a symbol of the Society culture of traffic can lead city planners to get right decisions. The aim of this study is determining of the geographical distribution of traffic conflicts in Mashhad city and finding logical relationship between district geographical characteristics and the rate of traffic conflicts. The theoretical basis of this research is the theory of urban smart growth. This study in data collection and data assessment part is an evaluation research and it placed at practical research in part of results. The research method is descriptive - analytical study. Traffic conflict data collection was down by filming method and traffic volume data were achieved of Mashhad database system for intelligent control of traffic signals. Statistical sample includes 26 of total 189 signalized intersections of Mashhad city which two important types of traffic conflict rates were determined on them. Also geographical distribution assessment of traffic conflicts was done by GIS and assessing of relationship between district geographical characteristics and the rate of traffic conflicts was done by SPSS software. The research results revealed that geographical distribution of traffic conflicts in different districts are not the same and the rate of traffic conflicts in the Central city areas is more due to traffic cultural diversity and drivers who are unfamiliar to city network streets. Also it is revealed that there is a direct relationship between the rate of traffic conflicts and Population density.

Illegal traffic behavior has a main role in shaping traffic situation of a given city. The aim of this research is to find a logical relationship between characteristics of different regions and illegal traffic behaviors. The theoretical basis of research is on the concept of urban sustainability. The research method is descriptive - analytical study. Data collection has done by library methods and field observation using traffic control center equipment and street filming. The time for filming has specified after a period of exploration inventory and consideration of %95 degree of confidence and %1 error rate. The research hypothesizes were examined using "Compare Means, Paired- Samples T Test" and "Chi-Square" method in the SPSS environment. In total, 11 defined illegal traffic behaviors were surveyed main intersections of Mashhad city. The results revealed that among the factors examined included population, number of building completion certificate, average traffic volume and level of development, and the level of development of regions have a significant effect on illegal traffic behavior.

Construction of large commercial complexes in residential land-use (RLU) or green space land-use (GSLU) areas in the metropolitan centers of the country is growing more every day. Expansion of such complexes has different influences where one of the most important consequences is on the transportation side. In this study، the transport related effects of a specific land-use change will be investigated based on its location. The theoretical basis of this research is urban smart growth theory. The research method is descriptive - analytical study. Setting traffic indicators in normal conditions and their estimation in case of change to commercial land-use (CLU) have been simulated by employing Comprehensive Transport Data Bank (CTDB) of Mashhad city and a computerized simulating method. The results revealed that the effects of changing in land-use are related to its location in the city and also to the presence or lack of Mass Public Transport Systems (MPTS). In general، the transformation of RLU and GSLU to CLU in inner layer of the city causes fall in transport indicators while resulting is rise of them in outer layers. The differences are more noticeable for scenarios defined in presence of MPTS. This transformation is causing some cost-effective influences regarding transport and traffic indicators that have been estimated at the final section of this study.

Traffic conflicts are phenomenon which obviously reveal situation of traffic culture of the society and the behaviors of street network's users. Increasing in traffic conflicts not only decrease traffic safety level but also cause negative effects in all aspects of traffic system. Traffic conflict method is a common way for traffic safety assess. Especially it is more effective in developing countries situation which have road users with different behaviors. In this paper, first, it is discussed the importance of traffic safety and the worthy role of traffic conflict method in this respect. In the second part, the especial traffic conflict types are defined respect to Mashhad road user's behaviors. Finally, Traffic conflict prediction models are developed for Mashhad signalized intersections. For this purpose, weve used three types of data consist of traffic volume and speed, geometric design and observed traffic conflict characteristics. Totally, 60 independent variables related to mentioned types were defined and assessed. The SPSS software, Multiple linear regression analysis and enter method were used to establish the relationship between different types of traffic conflicts and the intersection variables. 16 signalized intersection of Mashhad were assessed and 11 types of traffic conflicts were modeled. Study results reveals that the most effective traffic conflict factors are respectively traffic volume, quality of road marking, geometric design and signal phasing.