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Traffic congestion has been identified as a significant contributor to the environmental degradation and elevated fuel consumption. The causes of traffic delays are multifaceted, with toll booths positioned on highways being a notable factor. This study aims to analyze the impact of toll booths on traffic congestion, with a particular focus on the case study of the highway toll booth in question. The analysis will include a comparison of the delay times before and after the implementation of the FASTag system. The study will also undertake an economic evaluation to assess the cost implications of delay. The findings of this study indicate that congestion is more pronounced in the presence of manual toll booths compared to automated systems. The present study uses the 'Chakiya Toll Plaza on National Highway 27A, located between Motihari and Muzaffarpur, as a case study. This toll booth has been initially operated with a manual toll collection system, but has since transitioned to the FASTag implementation. A comprehensive analysis encompasses both traffic volume and delay studies, with a focus on their environmental and economic ramifications. The analysis reveals that for each Passenger Car Unit (PCU), the environmental cost is 8.3 rupees and the fuel cost is 15.34 rupees. The idle time cost is calculated as 8.34 rupees. The overall cost of the manual toll collection delay, including all the aforementioned factors, is found to be 52.3 rupees. However, the implementation of FASTag significantly reduces this cost to. 8.20 rupees. [ABSTRACT FROM AUTHOR]

This paper offers a comparative study of traffic delay times at intersections using two methodologies: the established Highway Capacity Manual (HCM) methodology and a machine learning vision system (MLVS). Two intersections in Tuscaloosa, Alabama--Hackberry Lane and Peter Bryce Boulevard, known for substantial traffic volume and proximity to the University of Alabama, and the newly established 2nd Avenue and Coliseum Circle--served as the empirical settings of the study. The goal of this paper was to examine the feasibility of automated delay measurement and level of service reporting. For the second intersection, paired f-test was utilized to evaluate the variations in delay times produced by the HCM method and MLVS. The analysis used was able to identify statistically significant similarities and differences at the intersections between the two methodologies. While both methods show general alignment in delay measurements for minor movements, significant differences were observed for major movements. The MLVS, which measures delay in real-time on a per-vehicle basis, tends to report lower delays compared to the HCM method, particularly in high-volume conditions. This discrepancy may be attributed to the HCM's reliance on empirical equations that do not account for real-time fluctuations in traffic flow. These findings suggest that the MLVS offers advantages in capturing dynamic traffic conditions. The findings urge future research to broaden the scope by exploring diverse intersection types over extended periods. The study acknowledges the HCM's reliability in traffic analysis while illustrating the potential benefits of integrating machine learning techniques into future traffic management strategies for smart cities approach. [ABSTRACT FROM AUTHOR]

In urban signalized intersections, because of the mixing of straight-going and right-turn vehicles in the straight-right shared lane, the straight traffic may block the rear right-turn vehicles from crossing the intersection during the red light, resulting in additional waiting time for right-turn vehicles. To address this problem, this study proposed the dynamic straight-right lane (DSRL) design and corresponding signal control schedule, which separates the straight-going and right-turn vehicles in space–time, making vehicles enter the intersection in an orderly manner. Then, the key parameters of the signal timing scheme were identified, and the physical significance of the key parameters of the optimal signal timing and the calculation models were given by discussing the optimal process of traffic flow operation at the signalized intersection. Finally, taking a realistic T-shaped signal intersection inlet lane as an example, the simulation verification platform was built by VISSIM to analyze the effects of variables on the performance of the DSRL proposed in this study. The results showed that the design proposed in this study can significantly reduce the right-turn vehicle delay without changing the overall layout of the signal intersection, and the total delay optimization rate at the intersection can always reach 10%–30%. [ABSTRACT FROM AUTHOR]

The number of shopping malls and vehicles in Baghdad has quickly increased along with the city's population. This has resulted in an increase in daily trips, which affects the roadway network's traffic flow and causes congestion, particularly on Al-Mansour Street and Al-Rowad Street near the city center. To determine the best signal time, the 14th Ramadan signalized intersection was evaluated and analyzed using the SIDRA 8.0 and SYNCHRO 11.0 software. First, the findings revealed that the chosen traffic facility is presently experiencing a substantial reduction in service level that is leading to forced conditions (LOS "F"). It is suggested that the cycle time at the intersection of the 14th Ramadan be changed from 240 seconds to 160 seconds and 125 seconds in SIDRA and SYNCHRO, respectively. Signal timings have reduced the delay for the 14th Ramadan intersection (76.8%), thus improving LOS from (F) to (D) for the intersection. The best delays after optimization in SYNCHRO 11.0, however, were 31% reduction with LOS of (E and D). Cycle times have also been lowered for the intersection to 25% as part of the optimum signal timing optimization. In SYNCHRO 11.0, which is better than SIDRA 8.0, the back of the queue has improved at the 14th Ramadan intersection by 33%. However, SYNCHRO has a better representation than SIDRA for current traffic saturation. [ABSTRACT FROM AUTHOR]

To improve traffic efficiency and reduce pollutant emissions at urban road intersections, VISSIM software was used to simulate traffic states to compare the median U-turn method with the direct left-turn method under various traffic volumes and left-turn ratios. Based on the average delay and CO emissions, suitable conditions were identified for using the median U-turn method at intersections. The results show that there are three critical left-turn ratio boundary curves named R d c r i (1) , R d c r i (2) , and R d c r i (3) based on the relatively smaller average delay and there is a critical left-turn ratio boundary curve R C O c r i based on the lower average CO emissions at the intersection when the through traffic volume is in the range of 0–3000 veh/h and the left-turn ratio is in the range of 0–4. The median U-turn method is considered applicable at the intersection when the through traffic volumes are in the range of 0–87 veh/h, 87–400 veh/h, 400–416 veh/h, 416–934 veh/h, and 934–3000 veh/h, respectively, and, accordingly, the left-turn ratios are in the range of 0– R d c r i (2) , 0– R d c r i (2) or R d c r i (1) –4, 0–4, 0– R d c r i (3) , and R C O c r i – R d c r i (3) . These findings can provide a reference for traffic managers to organize the left-turn traffic at an intersection reasonably. [ABSTRACT FROM AUTHOR]

Considering the differences in traffic delays and accident costs at different stages of the shipping cycle, this study develops a system dynamics model to determine the impacts of the shipping cycle on traffic delays and accident costs at port collector-distributor roads. Taking the collector-distributor roads of Yangshan Deepwater Port in Shanghai as a case study, parameter estimation and a model validity test are conducted. The changes in traffic delays and accident costs before and during maintenance activities at different stages of the shipping cycle are analyzed by increasing the growth rates of gross domestic product (GDP), and secondary and tertiary industries in GDP. The model results show that, as the economic growth rate increases, the growth magnitudes of traffic delays and accident costs during a peak period are significantly larger than those during a trough period. The results of this study provide policies and suggestions for improving traffic efficiency and safety on port collector-distributor roads. It is suggested to increase the maintenance frequency and maintenance funds during a peak period. Additionally, it is necessary to develop an intelligent road maintenance system for port collector-distributor roads that takes the shipping cycle into account in order to enhance the road safety level. [ABSTRACT FROM AUTHOR]

The number of shopping malls and vehicles in Baghdad has quickly increased along with the city's population. This has resulted in an increase in daily trips, which affects the roadway network's traffic flow and causes congestion, particularly on Al-Mansour Street and Al-Rowad Street near the city center. To determine the best signal time, the 14th Ramadan signalized intersection was evaluated and analyzed using the SIDRA 8.0 and SYNCHRO 11.0 software. First, the findings revealed that the chosen traffic facility is presently experiencing a substantial reduction in service level that is leading to forced conditions (LOS "F"). It is suggested that the cycle time at the intersection of the 14th Ramadan be changed from 240 seconds to 160 seconds and 125 seconds in SIDRA and SYNCHRO, respectively. Signal timings have reduced the delay for the 14th Ramadan intersection (76.8%), thus improving LOS from (F) to (D) for the intersection. The best delays after optimization in SYNCHRO 11.0, however, were 31% reduction with LOS of (E and D). Cycle times have also been lowered for the intersection to 25% as part of the optimum signal timing optimization. In SYNCHRO 11.0, which is better than SIDRA 8.0, the back of the queue has improved at the 14th Ramadan intersection by 33%. However, SYNCHRO has a better representation than SIDRA for current traffic saturation

The transportation demands of people are increasing day by day depending on the population, and the number of vehicles in traffic is causing various problems. To meet the energy needs of vehicles, there is a huge burden on countries in terms of fossil fuels. In addition, the use of fossil fuels in vehicles has a serious impact on environmental pollution. Various studies have been carried out to prevent unnecessary fuel consumption and emissions. Behavior of drivers, who are important components of traffic, are carefully examined in the context of this subject. Driver distraction causes various environmental problems as well as traffic safety issues. In this study, the negative situations that arise as a result of drivers waiting at traffic lights dealing with their mobile phones are discussed. Roadside observations are made for drivers at considered intersections in Erzurum Province, Turkey. As a result of these observations, delays at selected intersections due to mobile phone use are calculated. Unnecessary fuel consumption and emissions due to delays are also analyzed. An annual fuel consumption of approximately 177.025 L and emissions of 0.294 (kg) NOX and 251.68 (kg) CO2 occur at only selected intersections. In addition, a second roadside observation is made in order to analyze driver behavior and the most preferred type of mobile phone usage is determined. It is seen that drivers mostly exhibit the "Talking" and "Touchscreen" action classes. Considering the economic conditions and environmental pollution sensitivities of countries, attempts have been made to raise awareness about fuel consumption and emissions at traffic lights. [ABSTRACT FROM AUTHOR]

Direct vehicle access at site is usually restricted in situations where the driveway corner clearance (DCC) is designated, as per the District Unit Planning Guidelines. Currently, no clear installation standard for the DCC in Korea exists; thus, vehicles are allowed access regardless of the clearance between the driveway and the intersection. When driveways are located adjacent to the intersection, frequent conflicts between vehicles on minor and major roads occur. This results in problems with traffic communication and safety, necessitating a reasonable design. Therefore, in this study, DCCs were classified into upstream driveway corner clearance (UDCC) and downstream driveway corner clearance (DDCC), and algorithms and scenarios for calculating the appropriate DCC distance were proposed. DDCC was calculated from the traffic volume entering the rightmost lane of the DDCC from among the 12 intersection directions by applying optimized signal phase sequence and car-following theory. The DDCC results demonstrated that at least one vehicle in the driveway can exit to the rightmost lane on the roadway at 9.22 m. Two vehicles can exit at 32.15 m, and three vehicles can exit at 67.54 m. UDCC was calculated by considering its geometry, the traffic volume, queue length, and the 8.45 m additional distance from the driveway. Therefore, as traffic volume increased, the queue length and queue clearance time of the queue increased. The calculated DCC distance proposed in this study can contribute to establishing design standards in the future when establishing guidelines for district unit planning. [ABSTRACT FROM AUTHOR]

Aiming at the problem of low throughput and energy efficiency caused by the mutual restriction of energy efficiency and spectral efficiency in massive MIMO systems and the fact that resource allocation does not consider the factors of user service QoS and the upper and lower speed limits, a resource joint optimization method based on user service QoS guarantee is proposed. The method first performs user scheduling according to service delay and channel state under the condition of equal power distribution and calculates the current system capacity, and then combines transmit antenna power and service QoS constraints to redistribute power, and corrects the system capacity, establishing the objective function for the joint optimization of the spectral efficiency and energy efficiency. An algorithm combining deep learning and Q learning is used to solve the problem, and finally, the purpose of joint optimization is achieved. The simulation shows that the joint optimization method proposed in this paper can control the timeout of user data packets more finely and, at the same time, obtain greater energy efficiency and throughput. [ABSTRACT FROM AUTHOR]

To improve traffic efficiency and reduce pollutant emissions at urban road intersections, VISSIM software was used to simulate traffic states to compare the median U-turn method with the direct left-turn method under various traffic volumes and left-turn ratios. Based on the average delay and CO emissions, suitable conditions were identified for using the median U-turn method at intersections. The results show that there are three critical left-turn ratio boundary curves named Rdcri(1), Rdcri(2), and Rdcri(3) based on the relatively smaller average delay and there is a critical left-turn ratio boundary curve RCOcri based on the lower average CO emissions at the intersection when the through traffic volume is in the range of 0–3000 veh/h and the left-turn ratio is in the range of 0–4. The median U-turn method is considered applicable at the intersection when the through traffic volumes are in the range of 0–87 veh/h, 87–400 veh/h, 400–416 veh/h, 416–934 veh/h, and 934–3000 veh/h, respectively, and, accordingly, the left-turn ratios are in the range of 0–Rdcri(2), 0–Rdcri(2) or Rdcri(1)–4, 0–4, 0–Rdcri(3), and RCOcri–Rdcri(3). These findings can provide a reference for traffic managers to organize the left-turn traffic at an intersection reasonably.

Today, the motorization level and the value of traffic flow on the street-road network have increased. Often this leads to an excessive load on the existing traffic management system, highways, and roads. As a result, the number and duration of traffic delays are increasing, especially within populated areas. The consequence of this is the formation of traffic jams, increase of fuel and lubricants consumption, noise pollution, and emissions of exhaust gases. Another, no less critical consequence is an increase in traffic accidents, particularly at unsignalized intersections. Therefore, a traffic light control system is often implemented at street intersections to increase traffic safety and reduce the number of conflicting flows. In addition, this system should be optimized for signalized objects. The object of the study is a signalized intersection of multi-lane streets located in the city. The main problem that needs to be solved is the reduction of the vehicles` delay duration at the approaches to such intersections, in particular with the use of appropriate organizational measures and planning of the traffic light control system. According to the study's results, regularities were revealed regarding the change in the traffic's delay duration depending on the share of the permissive signal and the duration of the traffic light's cycle at the street intersection. At the same time, the received modulation results in the PTV Vissim software environment indicate an increase in delay values with an increase in the duration of the traffic light cycle. However, an equally important influence factor is the share of the permissive signal, as it reduces to a certain extent the duration of vehicles in standby mode at the approaches to the signalized intersection. The obtained results are recommended to be used in both developing new traffic organization schemes at signalized street intersections and improving existing ones.

Signal optimisation is essential in traffic engineering. The traffic light control timings should be set as optimum. However, it is challenging because the traffic network is a non-polynomial problem. In this study, the problem is evaluated from a unique perspective. The primary idea is to remove the crossings of the intersections. A Hamiltonian cycle algorithm has been used to design the network. So, vehicles are only able to join or split. Thus, no control mechanism is needed that delays or interrupts the flow. The suggested algorithm and intersection design were tested on Allsop and Charlesworth's widely used sample network. Findings were compared with the literature in the form of delay calculated using the Highway Capacity Manual 2010 formula. The suggested network's delay is calculated to be 98.17% and 95.45% less than the original network and recently published study-based delay, respectively. As a result, Hamiltonian roads seem sustainable in time and fuel consumption and could be used for future designs. [ABSTRACT FROM AUTHOR]

One of the most serious and worsening problems in much of the world is traffic congestion, which represents an undoubted menace to the quality of urban life, including wasting of time, and environmental pollution. Therefore, this study proposes a new dynamic cooperative traffic control algorithm based on Vehicle-to-Infrastructure connections to solve this problem. The proposed model contains three parts. First of all, when each vehicle enters the communication zone, it sends its estimated range of arrival time to the control center in the intersection; then the optimal passing sequence is calculated in the control center by dynamically grouping the compatible trajectories with the respect of the related safety constraints; finally, each vehicle optimizes its appropriate speed profile based on the given optimal time and speed to enter the intersection, which is sent by the control center. Several simulation cases are executed for different traffic volumes, whose results prove that vehicles under the proposed algorithm can pass the intersection with less travel time compared with traditional traffic control methods and other algorithms. Therefore, the proposed method can reduce the time delay and improve traffic efficiency. [ABSTRACT FROM AUTHOR]

In addition to a wide range of socio-economic impacts, traffic congestion during the era of the COVID-19 pandemic has been identified as a critical issue to be addressed. In urban neighborhoods, the timespan of traffic congestion hazard (HTC) after the curfew lift is subjected to the commuters' decisions about home-to-shopping center departures. The decision for departing early or late for shopping depends on both the internal (commuter related) and external (shopping center related) factors. The present study developed a practical methodology to assess the HTC period after the curfew timings. An online questionnaire survey was conducted to appraise the commuters' perception about departure time and to assess the impact of eight internal (family size, involvement in other activities, nature of job, education level, age, number of vehicles, number of children, and availability of personal driver) and three external (availability of shopping center of choice in near vicinity, distance to shopping center, and size of the city) factors on their decision. With an acceptable 20% response rate, Chi-square and Cramer's V tests ascertained family size and involvement in other activities as the most significant internal factors and availability of shopping center of choice as the primary external factor. Age, number of children, and size of the city influenced to some extent the commuters' decisions about early or delayed departure. Large associations were found for most of the factors, except education level and availability of drivers in a household. Fuzzy synthetic evaluation (FSE) first segregated the commuters' responses over a four level-rating system: no delay (0), short delay (1), moderate delay (3), and long delay (5). Subsequently, the hierarchical bottom-up aggregation effectively determined the period of highest traffic congestion. Logical study findings revealed that most (about 65%) of the commuters depart for shopping within 15 min after the curfew lift, so HTC in the early part (the first one hour) of the no curfew period needs attention. The traffic regulatory agencies can use the proposed approach with basic socio-demographic data of an urban neighborhood's residents to identify the HTC period and implement effective traffic management strategies accordingly. [ABSTRACT FROM AUTHOR]

In narrow waterways, navigation restrictions are imposed on vessels based on beam and length to safely accommodate two-way traffic. Each transit in a narrow waterway can potentially generate delay for the rest of the vessels in the opposite direction. In this paper, first an algorithm is developed to model the two-way traffic with beam restrictions and to quantify delay due to such restrictions. Next, procedures are presented to determine parameters such as destination docks and vessel arrival and departure times based on the automatic identification system (AIS) and local pilot data. The models and the solution algorithms are applied on three restricted sections of the Houston Ship Channel, and the number of impacted vessels and total delays is presented for each section. The proposed model and solution algorithm can be used in many studies, such as expansion projects, vessel scheduling, and ordering optimization. To show the applicability of the model, a scheduling model is presented in the paper. [ABSTRACT FROM AUTHOR]

The methods and results of the investigation of intervals between vehicles during queue dissipation before controlled intersections with the further determination of saturation flow are reviewed in this paper. Having reviewed existing methods of determining the saturation in traffic flows, those are determined which provide the most certain results in conditions of intensivemovement and take into account quite a large number of impact factors. Such methods are based on experimental measurement of intervals between vehicles during their passage through the stop-line in different directions of the controlled intersection. For the completeness of the analysis of such intervals, such factors are considered additionally as traffic composition and use of lanes by directions. Objects of the research are controlled intersections on approaches to which the slope is absent, there is no pedestrian and cyclist movement during the performance of turn, and conflicting traffic flows and also public transport stops in the zone of the intersection. The transitional research result is the determination of the number of vehicles that pass the stop-line during the permissive signal and time intervals between them, and the final result is the oncoming of saturation period on the lanes of straight and turns movement depending on traffic flow composition.

In contemporary urban areas, the construction speed of urban roads lags far behind the growth rate of the number of vehicles. The traffic delay caused by excessive vehicles is a major challenge for modern transportation systems. In this paper, we design an adaptive coordination traffic signal control system based on a three-level framework. In the framework, we propose a hierarchical strategy, which is helpful in avoiding possible offset conflicts and configuring the offsets reasonably. In addition, we establish a multi-intersection traffic signal control model with the goal of minimizing traffic delays. To solve the proposed model, we propose a new algorithm, called the Immune-Fireworks algorithm (IM-FWA), on the basis of the artificial immune and fireworks algorithms. Inspired by the antibody maintenance mechanism, diversity mechanism and communication mechanism of the artificial immune algorithm, IM-FWA can effectively overcome the shortcomings of the fireworks algorithm, such as its limited search range and lack of interaction among fireworks. The experiments show that the proposed model and algorithm have good practicability and that our control system can obtain a better signal timing schedule to effectively reduce traffic delays. [ABSTRACT FROM AUTHOR]

The article is devoted to the methodology and research results of traffic flow parameters on the arterial streets, where different regimes of prioritizing urban public transport operate. The regularities of changes of such parameters make it possible to identify and differentiate the sections of transport network in terms of service efficiency, with the aim to implement various regulatory measures that would help to minimize delays in traffic flow. Quantitative and qualitative criteria for ensuring priority transit of urban public transport on different sections of transport network depending on the intensity, speed and composition of traffic, as well as the roadway parameters are defined and substantiated. According to the research outcomes, scientifically based approaches are recommended for the implementation of different schemes of traffic flows control on the sections of the transport network, which differ in planning parameters and of traffic conditions and provide rational transport service based on the criterion of time loss for movement of residents. These results are adequate for large and very large cities with dense construction area.

As an undesired behavior of the transport system, headway fluctuation or even bus bunching reduce reliability of bus stop service for waiting passengers. This paper proposes a pre-control method to improve the balance of service intervals at downstream stop through an adjustment of green time for bus passing, in which priority and delay of bus passing can be achieved. The proposed pre-control strategies at intersection are triggered based on prediction of service intervals at downstream stop to select priority or delay strategy that includes adjusting starting and ending time of green light. Meanwhile, the influence of adjustment of green time on surrounding traffic delay of vehicle is also considered. The traffic delay is estimated for vehicles arriving during phases within associated two signal cycles induced by the signal adjustment. To derive optimal adjustment of green time, a multi-objective function is established and the objectives include deviation of the bus service intervals and traffic average delay. An exhaustive search algorithm is programmed to solve the objective function. The effects of control strategies are tested by numerical experiments based upon a real bus route in Changchun. Results show that the bus service reliability can be improved through a proper signal pre-control and, compared with the single control strategy with only bus delay, the standard deviations of service intervals with the average running time and the stochastic running time are improved by 8.53% and 7.31%, respectively.

One of the most serious and worsening problems in much of the world is traffic congestion, which represents an undoubted menace to the quality of urban life, including wasting of time, and environmental pollution. Therefore, this study proposes a new dynamic cooperative traffic control algorithm based on Vehicle-to-Infrastructure connections to solve this problem. The proposed model contains three parts. First of all, when each vehicle enters the communication zone, it sends its estimated range of arrival time to the control center in the intersection; then the optimal passing sequence is calculated in the control center by dynamically grouping the compatible trajectories with the respect of the related safety constraints; finally, each vehicle optimizes its appropriate speed profile based on the given optimal time and speed to enter the intersection, which is sent by the control center. Several simulation cases are executed for different traffic volumes, whose results prove that vehicles under the proposed algorithm can pass the intersection with less travel time compared with traditional traffic control methods and other algorithms. Therefore, the proposed method can reduce the time delay and improve traffic efficiency.

In addition to a wide range of socio-economic impacts, traffic congestion during the era of the COVID-19 pandemic has been identified as a critical issue to be addressed. In urban neighborhoods, the timespan of traffic congestion hazard (HTC) after the curfew lift is subjected to the commuters’ decisions about home-to-shopping center departures. The decision for departing early or late for shopping depends on both the internal (commuter related) and external (shopping center related) factors. The present study developed a practical methodology to assess the HTC period after the curfew timings. An online questionnaire survey was conducted to appraise the commuters’ perception about departure time and to assess the impact of eight internal (family size, involvement in other activities, nature of job, education level, age, number of vehicles, number of children, and availability of personal driver) and three external (availability of shopping center of choice in near vicinity, distance to shopping center, and size of the city) factors on their decision. With an acceptable 20% response rate, Chi-square and Cramer’s V tests ascertained family size and involvement in other activities as the most significant internal factors and availability of shopping center of choice as the primary external factor. Age, number of children, and size of the city influenced to some extent the commuters’ decisions about early or delayed departure. Large associations were found for most of the factors, except education level and availability of drivers in a household. Fuzzy synthetic evaluation (FSE) first segregated the commuters’ responses over a four level-rating system: no delay (0), short delay (1), moderate delay (3), and long delay (5). Subsequently, the hierarchical bottom-up aggregation effectively determined the period of highest traffic congestion. Logical study findings revealed that most (about 65%) of the commuters depart for shopping within 15 min after the curfew lift, so HTC in the early part (the first one hour) of the no curfew period needs attention. The traffic regulatory agencies can use the proposed approach with basic socio-demographic data of an urban neighborhood’s residents to identify the HTC period and implement effective traffic management strategies accordingly.

The research on the organization of intersections has always been the key and difficult point of road optimization, especially for multi-leg intersections. Since the traffic flow direction and the number of conflict points of multi-leg intersection are more than that of ordinary intersection, the difficulty of organization and optimization increases accordingly. At present, the research on multi-leg intersections is not much or deep enough at home and abroad. In general, it is transformed into a roundabout when the traffic volume is small, and the signal lamp is set with the increase of traffic volume. However, the signalized roundabout is not applicable when the traffic flow at the signal roundabout increases to a certain extent. Therefore, this paper introduces Huangsha six import signal free roundabout in Dianjiang County of Chongqing as the research case, takes the traffic delay and queue length as the evaluation index, and two new optimization methods are proposed on the basis of the original methods, namely improved the signalized roundabout and the signalized intersection. To assess the feasibility of these methods, VISSIM is used for simulation comparison. The simulation results show that compared with the current traffic situation, the average delay time of vehicles in the signalized intersection optimization method is reduced by 9.3 s, the average queue length decreased by 3.7 m, and its indicators are better than the signalized roundabout. Therefore, the method of signalized intersection not only provides a good mirror for the reconstruction of multi-leg intersections, but also offers relevant theoretical and practical exploration. [ABSTRACT FROM AUTHOR]

Optical networks are future networks that will support the vast bandwidth demand for communication in diverse domain and service applications scale to worldwide through underwater fiber optical for the demand of broadband Internet-traffic. The distribution of this network has grown to its extent, which can be utilized to get benefited through efficient multipath routing dynamically across multiple fiber-optic links to meet the bandwidth requirements, network load balancing and resource optimization. The increase in invariable traffic rate in communication make it very challenging to manage and provide the QoS. In this paper, we aim to present a solution on the efficiency of multipath routing based on the comprehensive bandwidth remaining and the variable traffic delay computation in an accepted optical paths known as Traffic Delay and Bandwidth based Multipath (TDB-MP) scheduling approach. The proposed TDB-MP approach will provide the most efficient routes for data routing is in situation of congestion with an optimal overhead and delay to accomplish high throughput. An experimental evaluation over a network simulator is performed to demonstrate the improvisation of the proposed approach at different network traffic load conditions. [ABSTRACT FROM AUTHOR]

Vehicular traffic at Obafemi Awolowo University has increased over the years, resulting in delay at The Main Gate -- Ede Road Intersection. This paper evaluated its present level of service with a view to addressing this situation. Geometric survey of the intersection was carried out. Peak hour traffic studies were conducted for a week and the traffic characteristics and volume were determined using standard procedure. The level of service (LOS) of the intersection was thereafter obtained. The geometrics of the intersection showed that, two lanes exist on the East Bound (EB) and West Bound (WB) approaches, as well as a dual lane on the North Bound (NB) and South Bound (SB) approaches. The traffic volume count was 1378, 931, 1168 and 1123 veh/h for the NB, SB, EB and WB respectively. The level of service at the intersection is B, thus implying that it exhibits a slight delay. [ABSTRACT FROM AUTHOR]

The oversaturated state of the intersection is mainly manifested as the queuing vehicles are not completely dissipated at the end of a green light phase.In order to cope with the traffic congestion,the mathematical model of an intersection is built.The relative regularity of arrival rate and departure rate of vehicles are analyzed.Through the analysis of the mechanism,the modeling of single-phase intersection,two-phase single intersection and four-phase single intersection are studied.The established oversaturated intersection delay model can be used to assign the green time of each intersection by calculating the minimum delay to alleviate the oversaturation condition of the city road.Numerical simulation results verify the validity and availability of the modeling method.

This paper demonstrates the relevance of accounting of traffic flows variability over time allows reducing intersection traffic delays in urban areas. The method of determining the optimal parameters of multiprogram control, allows considering the daily and hourly traffic flows variability was developed. Application of the optimized parameters of multiprogram control allows reducing intersection traffic delays up to 10-40% during a day compared to single-program control.

The average is usually applied to describe the traffic delay, and the environmental factors are considered to influence it. However, the distribution and the influencing individual behavior on traffic delay is seldom investigated. An observational study shows that pedestrian and vehicle delay follow exponential and power-law distributions. Since they are left-skewed and fat-tailed, the average delay fails to describe the Level Of Service (LOS) in some traffic conditions. To confirm that traffic delay follows these distributions in other situations, a simulation study is conducted. The results coincide with the empirical ones. A new indicator—the average of the longest 20% delay, is developed. It provides a better estimate of LOS than the average of the whole in describing traffic conditions, especially the congested ones. Moreover, pedestrian assertive behavior is a critical influencing factor on traffic delay. The results indicate that the characteristics of the delay distribution is worthy of note. Highlights Distribution of pedestrian and vehicle delay is left-skewed and fat-tailed. Traffic delay distributions explored through an observational and a simulation study. Pedestrian assertiveness is considered in the simulation model. A new indicator of LOS estimation is developed based on the 80/20 rule. [ABSTRACT FROM AUTHOR]

Intersection traffic delay research has traditionally placed greater emphasis on the study of through and left-turning vehicles than right-turning ones, which often renders existing methods or models inapplicable to intersections with heavy pedestrian and non-motorized traffic. In the meantime, there is also a need for understanding the relations between different types of delay and how they each contribute to the total delay of the entire intersection. In order to address these issues, this paper first examines models that focus on through and left-turn traffic delays, taking into account the presence of heavy mixed traffic flows that are prevalent in developing countries, then establishes a model for calculating right-turn traffic delay and, last, proposes an approach to analyzing how much each of the three types of traffic delay contributes to the total delay of the intersection, based on the application of shift-share analysis (SSA), which has been applied extensively in the field of economics.

Confined by the real-time and accuracy of traditional traffic collecting parameters, the existing traffic delay estimation models are generally with poor performance in guiding practical applications. In the Cooperative Vehicle-Infrastructure System, the real-time entire space-time driving state information of a single intelligent vehicle provides new data supporting for road traffic status evaluation. Fully extracting the value of this kind of new data, this paper proposes a new real-time traffic delay estimation method based on the Webster signalized intersection delay model. Taking each intelligent vehicle as a benchmark point, the vehicle arriving/leaving characteristics of the signalized intersection are spatially interpolated by the stopping state of a small amount of benchmark vehicles. In order to obtain the critical queuing dissipation point, the linear fitting method is used to forecast the critical stopping time and further the Markov model is used to estimate the number of queuing vehicles at the critical stopping time. Based on the real-time vehicle queuing characteristics, a new traffic delay estimation model is built according to the Webster estimation mechanism. The case study shows that, compared with the traditional Webster model, the proposed method can effectively improve the traffic delay estimating accuracy. [ABSTRACT FROM AUTHOR]

Highlights • The safety and operational impacts of extending the length of left-turn lanes at signalized intersections are evaluated. • Before/ after video data at three treated and matched control left-turn lanes is analyzed using computer vision techniques. • A marked reduction in traffic conflict counts in all treated sites was observed. • There was also a marked reduction in frequency of traffic conflicts at different severity levels. • The count of traffic signal cycles with blocked left-turn entrance was considerably reduced after the treatment. Abstract Left-turn lanes are commonly introduced to provide space to accommodate comfortable deceleration and adequate storage of turning vehicles. Operational shortcomings may arise due to inadequate length, including overflow and blockage of left-turn entrance by queues on an adjacent through lane. This study investigates the potential safety and operational benefits of treating left-turn lanes by extending the length further upstream a signalized intersection. Video data was collected at three treated left-turn lanes as well as three matched control lanes; all in both before and after treatment conditions. Safety parameters consisted of the counts and severities of traffic conflicts occurring on the left-turn lanes and inside the intersection. There was a marked reduction in traffic conflict counts in all treated sites. The overall treatment effect, which accounts for the simultaneous change in control sites, was 63.2% (p < 0.05). There was a marked reduction in frequency of traffic conflicts at different severity levels. The mobility benefit of the treatment was demonstrated in terms of the reduction in average travel time for left-turn as well as through vehicles. The count of traffic signal cycles with blocked left-turn entrance was considerably reduced after the treatment. The use of collision data gathered from more sites is suggested as potential future work to further evaluate this treatment. [ABSTRACT FROM AUTHOR]

Probabilistic yielding behavior is often observed at unsignalized crosswalks, but its impacts on the traffic flow in terms of traffic capacity and associated vehicular delay have not been examined before. The uniqueness of this problem is that neither traffic nor pedestrian flow holds the absolute priority as normally assumed in existing literature. Based on queuing theory, this paper developed traffic capacity and delay formulas considering the probabilistic priority. The proposed capacity equation reduces to the classic formula when the yielding rate equals one. The service time distributions for both queuers and non-queuers were derived, and M/G2/1 queuing model was applied to determine queue length and vehicular delay. Stochastic simulations showed that the proposed capacity and delay formulas precisely match the simulation results. For ease of practical applications, simpler queuing formulas including M/G/1, M/M/1 and M/D/1 were also examined. Noting that the differences between M/G2/1 and M/G/1 model are only marginal, especially for low yielding rates, we recommend theM/G/1 model for practical applications. In addition, when the pedestrian volume is relatively low, the M/M/1 model is also applicable due to its sufficient accuracy and simplicity. [ABSTRACT FROM AUTHOR]

Highway work zones create potential risks for both traffic and workers in addition to traffic congestion and delays that result in increased road user delay, traffic crashes, and vehicle emissions. The Federal Highway Administration (FHWA) and state departments of transportation (DOTs) are continuously seeking to improve work-zone safety and mobility. To accomplish this, the layout of highway work zones needs to be carefully planned and optimized to accomplish the multiple and often conflicting objectives of maximizing safety and mobility. This article presents the development of an innovative multiobjective optimization model to search for and identify a set of Pareto-optimal work-zone layouts that provide a wide range of optimal trade-offs between minimizing traffic delays and minimizing the probability of crashes. The model has four phases: (1) identify all relevant decision variables for work-zone layout, (2) formulate the optimization objective functions in the model, (3) define all relevant and practical constraints that affect the optimization problem, and (4) perform the model-optimization computations using multiobjective genetic algorithms. The performance of the developed optimization model was analyzed and verified using an application example of work-zone layout. The results of the analysis of this example illustrate the novel and unique capabilities of the developed model in searching for and identifying optimal work-zone layouts. These new and unique capabilities are expected to support state DOTs and construction planners in their ongoing efforts to maximize work-zone safety and reduce traffic delays in the work-zone area. [ABSTRACT FROM AUTHOR]

This paper proposes a methodology to categorize drivers’ behaviors at a congested signalized intersection. As a discrete event system model, timed Petri nets (TPNs) are used in this paper to formally define two kinds of behaviors: non-jam-induced driving behavior and jam-induced one. In order to systematically assess the performances of both behaviors, a new urban traffic network model is built: a cell transmission model is used to depict the road link traffic that is consistent with the kinematic property of traffic flow, and TPNs are used to model the behaviors and the conflicting traffic flow at the intersection. Some simulation results are given to evaluate the impact of driving behavior on the traffic delay. [ABSTRACT FROM PUBLISHER]

A comprehensive course design was carried out for strengthening the practical ability of student to learn knowledge and train ability. Traffic delay was a sub-task in the course design of traffic management and control. It can be got in many ways. The most common methods are the point sample method, HCM model, VISSIM simulation. Firstly, the basic principles of the three methods were fully understood for students. The relevant data should be surveyed on the basic principles of the three methods. Then the traffic delay was calculated by using the three methods. Finally, the advantages and disadvantages of the three methods were compared and analyzed. It was found that the course design was a good exercise for students to discover problems, analyze and solve the problems. The effect of the course design was good, and the course design has certain promotion significance. [ABSTRACT FROM AUTHOR]