Traffic signal using at CROSSWALKs directly effects on the safety of pedestrian and vehicles delay. Considering the importance of non- compliance traffic signals by some pedestrians and the effect of this problem on traffic signal setting has been discussed in this paper. First the relationship between duration of pedestrian green phase and pedestrian violation introduced. The problem developed a traffic signal optimization strategy that considers both vehicles and pedestrian. The objective of the method is to minimize the average vehicle delay under constraint of pedestrian green phase. The new algorithm is introduced to solve the problem. Finally, numerical example is solved by this algorithm to show the efficient of algorithm.

Delay at intersections constitutes a major part of travel time in urban networks. Nevertheless, in traffic assignment models, intersection delay is either ignored or assumed constant, due to difficulties in considering the delay for one approach as a function of various conflicting approach traffic volumes, as well as lack of appropriate functions to measure the delay. In this paper, by using the data which has been collected from five intersections in the city of Tehran, two types of delay function are presented which are, not only dependent on the traffic light setting and the approaching traffic volume, but, depend on the traffic volume in conflicting approaches.Moreover, based on the data collected in a SIGNALIZED intersection which was previously unSIGNALIZED, the effect of traffic light installation on an unSIGNALIZED intersection is closely studied. Finally, two actuated SIGNALIZED intersections are examined to see the effect of installed actuated traffic light systems upon intersection delay.

Background: The EuroQol five-dimensional 5 level (EQ-5D-5L) value set is not currently available for the Iranian general public, while the value set for EuroQol five-dimensional 3 level (EQ-5D-3L) is available. The present study aimed to generate an interim EQ5D-5L value set for the context of Iran. Methods: The Iranian interim EQ-5D-5L value set was generated using the CROSSWALK method, which maps EQ-5D-3L and EQ-5D5L responses. The EQ-5D-3L value set has previously been estimated by Time Trade-Off (TTO) method. The interim value set obtained for EQ-5D-5L was compared with the value set of EQ-5D-3L by using measures of mean, median, and skewness. The analysis was done using STATA version 15. Results: The mean and median scores of the Iranian interim value set were 0. 499 and 0. 451 for EQ-5D-5L and 0. 455 and 0. 459 for Iranian EQ-5D-3L, respectively. The range of value for both EQ-5D-3L and interim EQ-5D-5L was-0. 113 to 0. 919. Data skewness of EQ-5D-3L and interim EQ-5D-5L was-0. 099 and-0. 114, respectively. In addition, the figure of distribution of value sets for both data sets had a tail extended towards the left. The states of “ good health” (i. e., states with value>0. 8) for the EQ-5D-3L value set were proportionally more than the Iranian interim EQ-5D-5LCROSSWALK value set (2. 47% vs. 0. 448%). Conclusion: An EQ-5D-5L value set was generated using the CROSSWALK method for the Iranian general public, and now researchers and policy-makers can apply it to their economic and clinical analyses.

Population growth, land-use development, and car ownership increasing in -cities would enhance trip demand and volume of passing vehicles in urban streets dramatically. In case of traffic congestion, travel time in urban transportation network is one of the major problems of mega cities. It is noteworthy that an important portion of travel time is caused by control delay at SIGNALIZED intersections, so study of control strategies and methods is necessary. Furthermore, intelligent control methods would increase variety and ability which are result of -investing on the manner of SIGNALIZED intersection control.Using fuzzy logic as a means of control in engineering problems has a successful history. This approach of control has proved its efficiency in practical problems. Fuzzy logic, similarly, is used in transportation engineering problems. In this study, an appropriate environment for evaluation of different control algorithm of SIGNALIZED intersections is provided. In addition, a new method based on fuzzy control is proposed and evaluated. Also, various tests in this simulation environment are applied for different volumes and geometric conditions. In fact, applying this algorithm can improve performance indices, specially, in comparison with fixed and traditional vehicle actuated methods. On the whole, using two contemporary fuzzy variables and new method for determination of membership function are remarkable differences between this study and formers.

Due to the fact that one of the most significant reasons for pedestrian accidents in SIGNALIZED intersections is the crossing violation of pedestrian, therefore, the evaluation and investigation of factors affecting pedestrian violations have always been a concern for traffic safety activists. The aim of this study was to evaluate the external factors affecting pedestrian violations, especially factors related to geometric design and traffic condition. The behavior of 1590 pedestrians was captured in 10 CROSSWALKs of 6 intersections in Mashhad, and the effect of 15 unique variables on each pedestrian was evaluated. Binary Logistic Regression used for data analysis by using SPSS software. Finally, the variables of the number of pedestrians on the side, the number of violating pedestrians on the side, the waiting time, the gap of the vehicle, the length of the CROSSWALK, the width of the median and the time of the pedestrian light was found to be effective on the pedestrian decision to cross. The analysis shows that increasing number of pedestrians would reduce the probability of violation 20. 7%. Moreover, if the number of violating escorting pedestrians increases, the probability of violation would increase 81. 4%. The increase of one unit in “ pedestrian’ s waiting time” , “ length of the CROSSWALK” , “ width of median” would result in violation reduction of 13. 2%, 18. 5%, and 14. 6%, respectively. On the other hand, an increase of one unit in “ vehicles’ headway” and “ duration of red light” would increase the violations 17. 8% and 2. 8%, respectively.

In this paper, it has been tried to utilize a simple traffic element like U-Turn to solve the worst traffic problem which is the conflict between through traffic movements. This is currently being achieved by using intersections and traffic signals. This method - which was initiated in Tehran , by allocating relatively little budget would remove signalizations and continue the refuge to replace disrupted traffic with continuous traffic flow. The presented models in this paper are based upon traffic theories and actual field measurements. Currently, many of these U-Turns have been constructed in expressways and arterials of Tehran and have caused smooth traffic flow.

Development of disaggregate models for estimating different property damage collision type frequencies in urban intersections has rarely been studied, particularly in Iran. It seems that very little research work has been implemented for studying the factors affecting the collision type frequency at intersections. The main objective of this paper is to develop suitable statistical models to predict types of property damage accident frequencies at SIGNALIZED intersections approaches in the City of Mashhad, Iran, based on geometric, traffic and regulatory control characteristics. Three negative binomial models are estimated for collisions occurred in four-leg SIGNALIZED intersections in the city of Mashhad and their results were compared. These models are total, rear-end and right angel collision models. The goodness of fit was assessed by statistic tests. The Incidence Rate Ratio is used to assess the effectiveness of independent variables on frequency of property damage collision. Validation of models was controlled using paired samples T-test Method.Modeling collision types showed a strong relationship between frequency of property damage collision types and independent variables such as road geometry, the type of control system and traffic characteristics. Results revealed that seven of independent variables considerably affect the safety of SIGNALIZED intersections.

Accurate estimation of delay is difficult because of the randomness of traffic flow and large number of factors affecting intersection capacity. Existing delay models provide only approximated point of estimates of SIGNALIZED intersections. Identification and evaluation of probability distribution of delay can be beneficial in understanding the nature of its variability at SIGNALIZED intersections. In this study travel time delay data at three per-timed SIGNALIZED intersections in Tehran, Iran were evaluated. The main purpose of this research is to present a delay distribution prediction model based on the data collected at some SIGNALIZED intersections in Tehran. For this purpose the following steps have been taken:1. Literature reviews on queuing theory and existing delay models, well as well as theoretical support for the study.2. Sampling and data collection regarding delay of vehicles in some fixed time SIGNALIZED intersections in Tehran.3. Determination of delay distribution functions by existing vehicles delays values obtained from the data. For this purpose the frequency of delays (data) in various intervals was calculated and then, based on the obtained histogram of the data, a few distribution functions (i.e. Weibull, Gamma, Beta, Normal, Erlong, Triangular, Exponential and Uniform) were fitted to this data and consequently the best delay distribution function was obtained.4. Presentation of a model for predicting the delay time in some SIGNALIZED intersections in Tehran.Hence, delay probability distribution functions were developed for each SIGNALIZED intersection using Arena simulation software. Results of simulation show that Weibull distribution function provided better fits for delay data at all three intersections. The two parameters of this distribution were estimated by "average delay" and "g/c" ratio.