This document summarizes a study that analyzed the capacity of priority intersections using a conflict method. The study observed two intersections in Malaysia, one without flared lanes and one with flared lanes, to determine occupation times for different vehicle movements. Occupation time is the time a vehicle spends in the conflict area and is a key parameter of the conflict method. The study found the south right turn had the highest occupation time at both intersections due to conflicts with multiple streams. The conflict method was then used to calculate capacities and compare them to Highway Capacity Manual 2000 values. The results showed the conflict method produced comparable capacities to the HCM 2000.
This document summarizes an article from the International Journal of Mechanical Engineering and Technology that discusses optimizing traffic signal timing at an isolated intersection. The article aims to minimize delays and queue lengths through optimizing the duration of signal cycles and allocation of green times to phases. It first describes the current signal timing plan and traffic conditions at the intersection. It then calculates performance measures like capacity utilization and lost times using classical models. Finally, it formulates the problem as a linear program to optimize signal timing through minimizing queues and delays, with the goal of improving traffic flow at the intersection without physical changes.
Chapter 6 Fundamentals of traffic flowFayaz Rashid
The document discusses fundamental principles of traffic flow, including the primary elements of traffic flow such as flow, density, speed, and headway. It describes flow-density relationships and the fundamental diagram of traffic flow. Mathematical models for describing macroscopic traffic flow relationships are presented, including the Greenshields model relating traffic density to speed. The primary elements, flow-density relationships, and Greenshields traffic flow model are summarized for understanding traffic flow characteristics.
The document discusses modal split and trip distribution models in transportation planning. It describes the factors that influence mode choice such as trip characteristics, transportation facilities, and traveler attributes. Two main types of modal split models are discussed: trip-end models which are sensitive to short-term changes, and trip-interchange models which can incorporate long-term policy decisions. Trip distribution is the second stage of travel demand modeling and involves distributing trips from origins to destinations using methods like the growth factor model and gravity model.
This document summarizes different techniques for assigning routes in transportation network modeling. It describes the all-or-nothing assignment method, direction curve method, capacity restraint assignment techniques, and multi-route assignment technique. For each method, it provides details on the approach, limitations, and examples of models that use the technique. The document is presented by five students as part of their course on urban transportation systems.
This document provides a review and analysis of the optimal speed model. It discusses:
1) The theoretical models that support the optimal speed model including microscopic, mesoscopic, and macroscopic traffic flow models.
2) Problems with the original optimal speed model including unrealistic behavior, instability, and stop-and-go waves.
3) A proposed double boundary optimal velocity function model that allows vehicles to operate within a range of speeds and spacings rather than at a single optimal point. This addresses issues with the original model.
A study on gap acceptance of unsignalized intersection under mixed traffic co...eSAT Publishing House
This document summarizes a study on analyzing the capacity of unsignalized intersections under mixed traffic conditions in Visakhapatnam, India using the conflict technique method. Traffic data was collected through manual counts at three intersections to determine traffic volumes, flows, and capacities. The modified Tanner's formula capacity model was found to be most suitable. Tables and figures show the results of the traffic data collection, including the maximum number of vehicles and capacities for different turning movements at each intersection during morning and evening peak hours. The conclusions indicate the conflict technique is a simple method for this analysis and the modified Tanner's formula provided the best model.
Urban transportation system - methods of route assignmentStudent
The document discusses various methods of route assignment in transportation systems, including:
- All-or-nothing assignment method, which assigns all trips to the minimum path but does not account for capacity.
- Direction curve method, which predicts route usage based on travel time or distance saved on a new facility.
- Capacity restraint assignment techniques, which iteratively assign trips accounting for changing travel times due to congestion.
- Multi-route assignment technique, which recognizes that not all travelers choose the absolute minimum path and distributes trips across multiple routes factoring attributes like travel time and cost.
This document summarizes an article from the International Journal of Mechanical Engineering and Technology that discusses optimizing traffic signal timing at an isolated intersection. The article aims to minimize delays and queue lengths through optimizing the duration of signal cycles and allocation of green times to phases. It first describes the current signal timing plan and traffic conditions at the intersection. It then calculates performance measures like capacity utilization and lost times using classical models. Finally, it formulates the problem as a linear program to optimize signal timing through minimizing queues and delays, with the goal of improving traffic flow at the intersection without physical changes.
Chapter 6 Fundamentals of traffic flowFayaz Rashid
The document discusses fundamental principles of traffic flow, including the primary elements of traffic flow such as flow, density, speed, and headway. It describes flow-density relationships and the fundamental diagram of traffic flow. Mathematical models for describing macroscopic traffic flow relationships are presented, including the Greenshields model relating traffic density to speed. The primary elements, flow-density relationships, and Greenshields traffic flow model are summarized for understanding traffic flow characteristics.
The document discusses modal split and trip distribution models in transportation planning. It describes the factors that influence mode choice such as trip characteristics, transportation facilities, and traveler attributes. Two main types of modal split models are discussed: trip-end models which are sensitive to short-term changes, and trip-interchange models which can incorporate long-term policy decisions. Trip distribution is the second stage of travel demand modeling and involves distributing trips from origins to destinations using methods like the growth factor model and gravity model.
This document summarizes different techniques for assigning routes in transportation network modeling. It describes the all-or-nothing assignment method, direction curve method, capacity restraint assignment techniques, and multi-route assignment technique. For each method, it provides details on the approach, limitations, and examples of models that use the technique. The document is presented by five students as part of their course on urban transportation systems.
This document provides a review and analysis of the optimal speed model. It discusses:
1) The theoretical models that support the optimal speed model including microscopic, mesoscopic, and macroscopic traffic flow models.
2) Problems with the original optimal speed model including unrealistic behavior, instability, and stop-and-go waves.
3) A proposed double boundary optimal velocity function model that allows vehicles to operate within a range of speeds and spacings rather than at a single optimal point. This addresses issues with the original model.
A study on gap acceptance of unsignalized intersection under mixed traffic co...eSAT Publishing House
This document summarizes a study on analyzing the capacity of unsignalized intersections under mixed traffic conditions in Visakhapatnam, India using the conflict technique method. Traffic data was collected through manual counts at three intersections to determine traffic volumes, flows, and capacities. The modified Tanner's formula capacity model was found to be most suitable. Tables and figures show the results of the traffic data collection, including the maximum number of vehicles and capacities for different turning movements at each intersection during morning and evening peak hours. The conclusions indicate the conflict technique is a simple method for this analysis and the modified Tanner's formula provided the best model.
Urban transportation system - methods of route assignmentStudent
The document discusses various methods of route assignment in transportation systems, including:
- All-or-nothing assignment method, which assigns all trips to the minimum path but does not account for capacity.
- Direction curve method, which predicts route usage based on travel time or distance saved on a new facility.
- Capacity restraint assignment techniques, which iteratively assign trips accounting for changing travel times due to congestion.
- Multi-route assignment technique, which recognizes that not all travelers choose the absolute minimum path and distributes trips across multiple routes factoring attributes like travel time and cost.
A Review on Road Traffic Models for Intelligent Transportation System (ITS)IJSRD
Traffic flow models seek to describe the interaction of vehicles with their drivers and the infrastructure. Almost all the models directly or indirectly characterize the relationship among the traffic variables: the position, the speed, the flow, and the density of vehicles. These relationships can be based on either the behavior of individual vehicles in a traffic network in relation to the dynamics of other vehicles, the overall characteristics of the flow of vehicles in a traffic network, or a combination of the behavior of individual vehicles in a traffic network and the overall traffic flow characteristics. This paper describes the different models for automatic Traffic control system.
Experimental Comparison of Trajectory Planning Algorithms for Wheeled Mobile ...IJRES Journal
In this paper, we present an experimental approach to compare various trajectory planning methods for practical application of wheeled mobile robots. The first method generates a trajectory according to the acceleration limits of the mobile robot and its relationship with the curvature of the planned path. The second method is an improvement of the conventional convolution-based trajectory generation method, on which the heading angles of a curved path is being considered. Due to the limited scope of the considered constraints of the previous approaches, A third approach that conserves the merits of the convolution operator is proposed to consider the high curvature turning points of a sophisticated curve such as a Lemniscate of Gerono,which causes geometrical limitations during robot navigation. All methods are compared experimentally on a two-wheeled mobile robot. The goal of the experiment is to determine which approach meets the criteria of time optimality and sampling time uniformity while considering the physical limits of the mobile robot and the geometrical constraints of the planned path.
Traffic assignment models are used to estimate traffic flows on a transportation network based on origin-destination flows and the network's topology, link characteristics, and performance functions. Traffic is assigned to paths between origin-destination pairs based on travel time or impedance. Traffic assignment is a key part of travel demand forecasting and is used to predict future network flows and performance under different planning scenarios. Common traffic assignment methods include all-or-nothing assignment, user equilibrium assignment, and system optimum assignment.
8 capacity-analysis ( Transportation and Traffic Engineering Dr. Sheriff El-B...Hossam Shafiq I
This document discusses concepts related to transportation capacity analysis including:
- Definitions of level of service (LOS) categories A through F and their characteristics.
- How capacity is defined as the maximum hourly rate of vehicles that can pass a point under prevailing conditions.
- Procedures from the Highway Capacity Manual (HCM) for calculating capacity for basic freeway sections and the impacts of factors like lane width, lateral clearance, and free flow speed.
- The relationships between capacity, LOS, and transportation design and how capacity analysis can inform design.
Lecture 04 Capacity for TWSC (Traffic Engineering هندسة المرور & Dr. Usama Sh...Hossam Shafiq I
This document discusses gap acceptance theory and its application in determining the capacity of traffic movements at two-way stop controlled (TWSC) intersections. It covers key concepts such as critical gap (tc), follow-up time (tf), and impedance. An example calculation is provided to estimate capacity for different movements based on conflicting traffic volumes and tc/tf values. Adjustments to tc and tf for factors like vehicle type and number of lanes are also outlined. Finally, the document provides the Highway Capacity Manual (HCM) methodology for calculating control delay and level of service at TWSC intersections.
The International Journal of Engineering and Science (The IJES)theijes
This document summarizes a study that developed a Poisson regression model to predict train accidents at railroad crossings in East Java, Indonesia. The study analyzed data from 33 railroad crossings without guardrails, identifying factors like train speed, distance to warning signs, presence of flashing lights, and daily traffic volume as significant predictors of accidents. The final model included these four variables and showed the predicted number of accidents closely matched actual reported accidents at most sites.
The document discusses measures that can be taken to influence a modal shift from private cars to public transport in order to reduce traffic congestion in a city. It recommends conducting a stated preference survey to understand factors that influence travel choices. It also suggests implementing policies to dissuade car use such as prioritizing public transit at traffic signals, improving reliability and travel times of public transport, and providing more real-time transit information for passengers. Safety improvements for pedestrians are also highlighted.
Focused on the lane occupancy phenomenon, this paper analyzes the roads during two different accidents to the evacuation period. Firstly, according to the statistical data, this paper calculated the correction coefficients under the road traffic condition, and then obtained the actual traffic capacity result at each moment of the road when combining the function model of the actual traffic capacity corrected by the running speed and the road traffic condition. Next the actual traffic capacity results are fitted to the Smooth spline interpolation, and then the actual traffic capacity is further verified by the traffic congestion situation. The actual traffic capacity of the road during the accident to evacuation is summarized as follows: the actual traffic capacity shows a nonlinear trend, that is, ascending-attenuating-recovering and gradually stabilizing. Finally, using Mann-Whitney U test to carry out the difference test on the actual traffic capacity, it is found that there is significant difference between the two groups of data, and the actual traffic capacity of the second case is stronger than that of the first one, and the reasons for the difference are analyzed as follows: the ratio of the steering traffic volume at the downstream intersection is different; this road section includes the community intersection and there are vehicles entering and leaving; meanwhile the speed of each lane is different and there are buildings near the lane. The above conclusions will provide theoretical basis for the traffic management department to correctly guide the vehicle driving, approve the road construction, design the road channelization plan, set the roadside parking space and the non-port-type bus stations.
Exploring Queuing Theory to Minimize Traffic Congestion Problem in Calabar-Hi...Premier Publishers
Traffic congestion has been a serious problem that drivers are facing especially in Calabar – highway by IBB road intersection. In this paper, emphasis is placed on model formation and derivation of some parameters that will help to facilitate the flow of vehicles in this intersection to reduce traffic congestion. The channel considered in this research is multiple queue single servers. We derived variance waiting time of vehicles in the queue and in the system, expected number of vehicles in the queue and in the system waiting for service, expected waiting time of vehicles in the queue and in the system. We also determine the time each vehicle spends in the queue waiting for service and the mean queue length for all the channels in each section. The result shows fair traffic congestion in Calabar – highway by IBB road intersection especially in the morning and evening hours for all the locations.
This document discusses using algorithms to optimize tourism routes and logistics. It presents 3 scenarios applying the travelling salesman problem to determine optimal routes for visiting touristic places in Turkey. Scenario 1 finds the shortest routes between 10 places in the Aegean region. Scenario 2 identifies the optimal route that must include a specific place, Pamukkale. Scenario 3 calculates the lowest cost route that visits at least 2 places in each of 3 regions - Marmara, Aegean, and Mediterranean. The approach aims to minimize costs for tour companies while increasing customer satisfaction through personalized, flexible routing options.
Designing of a Traffic Signaling System at T-IntersectionIJERA Editor
The traffic signal design of the intersection has a direct control on its safety and operation from a design and user-ability point of view. We identified Kothavalasa T-Intersection has been arise problems like road accidents, conflicts and congestions. Design elements that are particularly important include the number of lanes provided on each approach and for each movement. These problems can solve by providing an efficient traffic signal control at the intersection for continuous movement of vehicles through the intersection. According to traffic signal, most traffic signal timing plans are designed to minimize vehicle delay based on the volumes seen in the past, not the present. Traffic count studies are to be made to determine the number, movement and classification of vehicles at an intersection. Signal timing is most important which is used to decide green time of the traffic light shall be provided at an intersection and how long the pedestrian walk signal should be provided. By using Highway Capacity Manual (HCM) intersection saturation for identifying periods of time when cycle length could be substantially short. These data is used identify normal flow of the roadway; determine the influence of heavy vehicles or pedestrians on vehicular traffic volume. Webster’s minimum delay cycle length equation overestimates the optimal cycle length compared to the results based on the HCM 2000 method. This is due to the restructuring of the HCM 2000 delay equation as compared to the original Webster’s delay calculation.
Congestion Effects of Parking and Pedestrians on Urban Road -A Case Study of ...ijsrd.com
Traffic congestion is a common phenomenon almost in all the cities of India. The situation has become to a very critical stage and has already assumed unbearable proportion in the cities of India. Cities of India cannot afford the economic and environmental loss resulted from this sever traffic Congestion. In this report, SBI to Bus-Station road in Modasa Town has been considered as study area. In the study area motorized and non-motorized vehicle creating congestion which has many negative effects. Traffic volume survey, Travel time delay study and informal occupancy survey has been conducted. A large number of vehicles occupy the road, reducing road capacity and creating congestion. In this study Average travel time delay measured due to Compared Speed-Density relationship with or Without Parking and Pedestrians and quantifies Congestion effect of Parking and Pedestrians.
The document reviews optimal speed car-following models. It discusses macroscopic and microscopic traffic models, with a focus on microscopic optimal speed models. The optimal speed model defines a desired speed that is a function of headway distance and helps model traffic flow situations. The document also proposes enhancements to the optimal speed model, including a weighting factor dependent on relative speed and spacing to improve braking reactivity. In conclusion, it evaluates optimal speed models and their ability to realistically model traffic dynamics while avoiding collisions.
This document provides a review of optimal speed traffic models. It begins with introductions to traffic modeling approaches including microscopic and macroscopic models. Microscopic models describe individual vehicle dynamics while macroscopic models use aggregated quantities like density and flow. The optimal velocity model is then defined as a car-following model where vehicles accelerate/decelerate to match an optimal speed based on headway. Properties, applications, and limitations of the optimal velocity model are discussed. Research on extensions like the full velocity difference model is also summarized. The document concludes with recommendations for further studying simulation problems to improve understanding of jam formation and congestion dynamics.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Adjusting the flow in crucial areas can maximize the overall throughput of traffic along a stretch of road. This is of particular interest in regions of high traffic density, which may be caused by high volume peak time traffic, accidents or closure of one or more lanes of the road.
Transportation modeling and planning ( The Four-Step Model )Ahmad Ali Miftah
This document describes transportation modeling and planning using the four-step model. It discusses data collection and characterization for the study area of North Cyprus. The four steps of the model are then explained: trip generation calculates the number of trips produced and attracted in each zone based on household surveys; trip distribution develops an origin-destination matrix to show trip flows between zones; modal split determines the proportion of trips using each transportation mode; and trip assignment allocates the trips to the transportation network. The document provides examples of applying each step of the four-step model to the study area.
Car-Following Parameters by Means of Cellular Automata in the Case of EvacuationCSCJournals
This study is attention to the car-following model, an important part in the micro traffic flow. Different from Nagel–Schreckenberg’s studies in which car-following model without agent drivers and diligent ones, agent drivers and diligent ones are proposed in the car-following part in this work and lane-changing is also presented in the model. The impact of agent drivers and diligent ones under certain circumstances such as in the case of evacuation is considered. Based on simulation results, the relations between evacuation time and diligent drivers are obtained by using different amounts of agent drivers; comparison between previous (Nagel–Schreckenberg) and proposed model is also found in order to find the evacuation time. Besides, the effectiveness of reduction the evacuation time is presented for various agent drivers and diligent ones.
Vehicle Headway Distribution Models on Two-Lane Two-Way Undivided RoadsAM Publications
The time headway between vehicles is an important flow characteristic that affects the safety, level of service, driver behavior, and capacity of a transportation system. The present study attempted to identify suitable probability distribution models for vehicle headways on 2-lane 2-way undivided (2/2 UD) road sections. Data was collected from three locations in the city of Semarang: Abdulrahman Saleh St. (Loc. 1), Taman Siswa St. (Loc. 2) and Lampersari St. (Loc.3). The vehicle headways were grouped into one-second interval. Three mathematical distributions were proposed: random (negative-exponential), normal, and composite, with vehicle headway as variable. The Kolmogorov-Smirnov test was used for testing the goodness of fit. Traffic flows at the selected locations were considered low, with traffic volume ranged between 400 to 670 vehicles per hour per lane. The traffic volume on Loc.1 was 484 vehicles per hour, that on Loc. 2 was 405 vehicles per hour, and that on Loc. 3 was 666 vehicles per hour. Random distribution showed good fit at all locations under study with 95% confidence level. Normal distribution showed good fit at Loc. 1 and Loc. 2, whereas composite distribution fit only at Loc. 1. It was suggested that random distribution is to be used as an input in generating traffic in traffic analysis at highway sections where traffic volume are under 500 vehicles per hour.
A Review on Road Traffic Models for Intelligent Transportation System (ITS)IJSRD
Traffic flow models seek to describe the interaction of vehicles with their drivers and the infrastructure. Almost all the models directly or indirectly characterize the relationship among the traffic variables: the position, the speed, the flow, and the density of vehicles. These relationships can be based on either the behavior of individual vehicles in a traffic network in relation to the dynamics of other vehicles, the overall characteristics of the flow of vehicles in a traffic network, or a combination of the behavior of individual vehicles in a traffic network and the overall traffic flow characteristics. This paper describes the different models for automatic Traffic control system.
Experimental Comparison of Trajectory Planning Algorithms for Wheeled Mobile ...IJRES Journal
In this paper, we present an experimental approach to compare various trajectory planning methods for practical application of wheeled mobile robots. The first method generates a trajectory according to the acceleration limits of the mobile robot and its relationship with the curvature of the planned path. The second method is an improvement of the conventional convolution-based trajectory generation method, on which the heading angles of a curved path is being considered. Due to the limited scope of the considered constraints of the previous approaches, A third approach that conserves the merits of the convolution operator is proposed to consider the high curvature turning points of a sophisticated curve such as a Lemniscate of Gerono,which causes geometrical limitations during robot navigation. All methods are compared experimentally on a two-wheeled mobile robot. The goal of the experiment is to determine which approach meets the criteria of time optimality and sampling time uniformity while considering the physical limits of the mobile robot and the geometrical constraints of the planned path.
Traffic assignment models are used to estimate traffic flows on a transportation network based on origin-destination flows and the network's topology, link characteristics, and performance functions. Traffic is assigned to paths between origin-destination pairs based on travel time or impedance. Traffic assignment is a key part of travel demand forecasting and is used to predict future network flows and performance under different planning scenarios. Common traffic assignment methods include all-or-nothing assignment, user equilibrium assignment, and system optimum assignment.
8 capacity-analysis ( Transportation and Traffic Engineering Dr. Sheriff El-B...Hossam Shafiq I
This document discusses concepts related to transportation capacity analysis including:
- Definitions of level of service (LOS) categories A through F and their characteristics.
- How capacity is defined as the maximum hourly rate of vehicles that can pass a point under prevailing conditions.
- Procedures from the Highway Capacity Manual (HCM) for calculating capacity for basic freeway sections and the impacts of factors like lane width, lateral clearance, and free flow speed.
- The relationships between capacity, LOS, and transportation design and how capacity analysis can inform design.
Lecture 04 Capacity for TWSC (Traffic Engineering هندسة المرور & Dr. Usama Sh...Hossam Shafiq I
This document discusses gap acceptance theory and its application in determining the capacity of traffic movements at two-way stop controlled (TWSC) intersections. It covers key concepts such as critical gap (tc), follow-up time (tf), and impedance. An example calculation is provided to estimate capacity for different movements based on conflicting traffic volumes and tc/tf values. Adjustments to tc and tf for factors like vehicle type and number of lanes are also outlined. Finally, the document provides the Highway Capacity Manual (HCM) methodology for calculating control delay and level of service at TWSC intersections.
The International Journal of Engineering and Science (The IJES)theijes
This document summarizes a study that developed a Poisson regression model to predict train accidents at railroad crossings in East Java, Indonesia. The study analyzed data from 33 railroad crossings without guardrails, identifying factors like train speed, distance to warning signs, presence of flashing lights, and daily traffic volume as significant predictors of accidents. The final model included these four variables and showed the predicted number of accidents closely matched actual reported accidents at most sites.
The document discusses measures that can be taken to influence a modal shift from private cars to public transport in order to reduce traffic congestion in a city. It recommends conducting a stated preference survey to understand factors that influence travel choices. It also suggests implementing policies to dissuade car use such as prioritizing public transit at traffic signals, improving reliability and travel times of public transport, and providing more real-time transit information for passengers. Safety improvements for pedestrians are also highlighted.
Focused on the lane occupancy phenomenon, this paper analyzes the roads during two different accidents to the evacuation period. Firstly, according to the statistical data, this paper calculated the correction coefficients under the road traffic condition, and then obtained the actual traffic capacity result at each moment of the road when combining the function model of the actual traffic capacity corrected by the running speed and the road traffic condition. Next the actual traffic capacity results are fitted to the Smooth spline interpolation, and then the actual traffic capacity is further verified by the traffic congestion situation. The actual traffic capacity of the road during the accident to evacuation is summarized as follows: the actual traffic capacity shows a nonlinear trend, that is, ascending-attenuating-recovering and gradually stabilizing. Finally, using Mann-Whitney U test to carry out the difference test on the actual traffic capacity, it is found that there is significant difference between the two groups of data, and the actual traffic capacity of the second case is stronger than that of the first one, and the reasons for the difference are analyzed as follows: the ratio of the steering traffic volume at the downstream intersection is different; this road section includes the community intersection and there are vehicles entering and leaving; meanwhile the speed of each lane is different and there are buildings near the lane. The above conclusions will provide theoretical basis for the traffic management department to correctly guide the vehicle driving, approve the road construction, design the road channelization plan, set the roadside parking space and the non-port-type bus stations.
Exploring Queuing Theory to Minimize Traffic Congestion Problem in Calabar-Hi...Premier Publishers
Traffic congestion has been a serious problem that drivers are facing especially in Calabar – highway by IBB road intersection. In this paper, emphasis is placed on model formation and derivation of some parameters that will help to facilitate the flow of vehicles in this intersection to reduce traffic congestion. The channel considered in this research is multiple queue single servers. We derived variance waiting time of vehicles in the queue and in the system, expected number of vehicles in the queue and in the system waiting for service, expected waiting time of vehicles in the queue and in the system. We also determine the time each vehicle spends in the queue waiting for service and the mean queue length for all the channels in each section. The result shows fair traffic congestion in Calabar – highway by IBB road intersection especially in the morning and evening hours for all the locations.
This document discusses using algorithms to optimize tourism routes and logistics. It presents 3 scenarios applying the travelling salesman problem to determine optimal routes for visiting touristic places in Turkey. Scenario 1 finds the shortest routes between 10 places in the Aegean region. Scenario 2 identifies the optimal route that must include a specific place, Pamukkale. Scenario 3 calculates the lowest cost route that visits at least 2 places in each of 3 regions - Marmara, Aegean, and Mediterranean. The approach aims to minimize costs for tour companies while increasing customer satisfaction through personalized, flexible routing options.
Designing of a Traffic Signaling System at T-IntersectionIJERA Editor
The traffic signal design of the intersection has a direct control on its safety and operation from a design and user-ability point of view. We identified Kothavalasa T-Intersection has been arise problems like road accidents, conflicts and congestions. Design elements that are particularly important include the number of lanes provided on each approach and for each movement. These problems can solve by providing an efficient traffic signal control at the intersection for continuous movement of vehicles through the intersection. According to traffic signal, most traffic signal timing plans are designed to minimize vehicle delay based on the volumes seen in the past, not the present. Traffic count studies are to be made to determine the number, movement and classification of vehicles at an intersection. Signal timing is most important which is used to decide green time of the traffic light shall be provided at an intersection and how long the pedestrian walk signal should be provided. By using Highway Capacity Manual (HCM) intersection saturation for identifying periods of time when cycle length could be substantially short. These data is used identify normal flow of the roadway; determine the influence of heavy vehicles or pedestrians on vehicular traffic volume. Webster’s minimum delay cycle length equation overestimates the optimal cycle length compared to the results based on the HCM 2000 method. This is due to the restructuring of the HCM 2000 delay equation as compared to the original Webster’s delay calculation.
Congestion Effects of Parking and Pedestrians on Urban Road -A Case Study of ...ijsrd.com
Traffic congestion is a common phenomenon almost in all the cities of India. The situation has become to a very critical stage and has already assumed unbearable proportion in the cities of India. Cities of India cannot afford the economic and environmental loss resulted from this sever traffic Congestion. In this report, SBI to Bus-Station road in Modasa Town has been considered as study area. In the study area motorized and non-motorized vehicle creating congestion which has many negative effects. Traffic volume survey, Travel time delay study and informal occupancy survey has been conducted. A large number of vehicles occupy the road, reducing road capacity and creating congestion. In this study Average travel time delay measured due to Compared Speed-Density relationship with or Without Parking and Pedestrians and quantifies Congestion effect of Parking and Pedestrians.
The document reviews optimal speed car-following models. It discusses macroscopic and microscopic traffic models, with a focus on microscopic optimal speed models. The optimal speed model defines a desired speed that is a function of headway distance and helps model traffic flow situations. The document also proposes enhancements to the optimal speed model, including a weighting factor dependent on relative speed and spacing to improve braking reactivity. In conclusion, it evaluates optimal speed models and their ability to realistically model traffic dynamics while avoiding collisions.
This document provides a review of optimal speed traffic models. It begins with introductions to traffic modeling approaches including microscopic and macroscopic models. Microscopic models describe individual vehicle dynamics while macroscopic models use aggregated quantities like density and flow. The optimal velocity model is then defined as a car-following model where vehicles accelerate/decelerate to match an optimal speed based on headway. Properties, applications, and limitations of the optimal velocity model are discussed. Research on extensions like the full velocity difference model is also summarized. The document concludes with recommendations for further studying simulation problems to improve understanding of jam formation and congestion dynamics.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Adjusting the flow in crucial areas can maximize the overall throughput of traffic along a stretch of road. This is of particular interest in regions of high traffic density, which may be caused by high volume peak time traffic, accidents or closure of one or more lanes of the road.
Transportation modeling and planning ( The Four-Step Model )Ahmad Ali Miftah
This document describes transportation modeling and planning using the four-step model. It discusses data collection and characterization for the study area of North Cyprus. The four steps of the model are then explained: trip generation calculates the number of trips produced and attracted in each zone based on household surveys; trip distribution develops an origin-destination matrix to show trip flows between zones; modal split determines the proportion of trips using each transportation mode; and trip assignment allocates the trips to the transportation network. The document provides examples of applying each step of the four-step model to the study area.
Car-Following Parameters by Means of Cellular Automata in the Case of EvacuationCSCJournals
This study is attention to the car-following model, an important part in the micro traffic flow. Different from Nagel–Schreckenberg’s studies in which car-following model without agent drivers and diligent ones, agent drivers and diligent ones are proposed in the car-following part in this work and lane-changing is also presented in the model. The impact of agent drivers and diligent ones under certain circumstances such as in the case of evacuation is considered. Based on simulation results, the relations between evacuation time and diligent drivers are obtained by using different amounts of agent drivers; comparison between previous (Nagel–Schreckenberg) and proposed model is also found in order to find the evacuation time. Besides, the effectiveness of reduction the evacuation time is presented for various agent drivers and diligent ones.
Vehicle Headway Distribution Models on Two-Lane Two-Way Undivided RoadsAM Publications
The time headway between vehicles is an important flow characteristic that affects the safety, level of service, driver behavior, and capacity of a transportation system. The present study attempted to identify suitable probability distribution models for vehicle headways on 2-lane 2-way undivided (2/2 UD) road sections. Data was collected from three locations in the city of Semarang: Abdulrahman Saleh St. (Loc. 1), Taman Siswa St. (Loc. 2) and Lampersari St. (Loc.3). The vehicle headways were grouped into one-second interval. Three mathematical distributions were proposed: random (negative-exponential), normal, and composite, with vehicle headway as variable. The Kolmogorov-Smirnov test was used for testing the goodness of fit. Traffic flows at the selected locations were considered low, with traffic volume ranged between 400 to 670 vehicles per hour per lane. The traffic volume on Loc.1 was 484 vehicles per hour, that on Loc. 2 was 405 vehicles per hour, and that on Loc. 3 was 666 vehicles per hour. Random distribution showed good fit at all locations under study with 95% confidence level. Normal distribution showed good fit at Loc. 1 and Loc. 2, whereas composite distribution fit only at Loc. 1. It was suggested that random distribution is to be used as an input in generating traffic in traffic analysis at highway sections where traffic volume are under 500 vehicles per hour.
Design of traffic signal on NH-12 near Barkatullah University, Bhopal Distric...IRJET Journal
This document summarizes a study on designing traffic signals on NH-12 near Barkatullah University in Bhopal, India. It begins with an abstract describing the growth of traffic in major towns due to industrialization and urbanization. The objectives of the study are to minimize delays at intersections, improve traffic flow, and enhance the level of service. Existing traffic volumes were measured using manual counts, and signals were designed using the Webster and two-phase signal methods. Key findings include calculated passenger car units per hour, saturation flow rates for different lane widths, and cycle times determined using the Webster method to minimize total vehicle delay. The study methodology involved manual traffic counts, conversion to passenger car units, and signal design using two-phase
Cooperative Traffic Control based on the Artificial Bee Colony IJERA Editor
This paper studies the traffic control problem in an isolated intersection without traffic lights and phase, because the right-of-way is distributed to each vehicle individually based on connection of the Vehicle-to-Infrastructure (V2I), and the compatible streams are dynamically combined according to the arrival vehicles in each traffic flows. The control objective in the proposed algorithm is to minimize the time delay, which is defined as the difference between the travel time in real state and that in free flow state. In order to realize this target, a cooperative control structure with a two-way communications is proposed. First of all, once the vehicle enters the communication zone, it sends its information to the intersection. Then the passing sequence is optimized in the intersection with the heuristic algorithm of the Artificial Bee Colony, based on the arrival interval of the vehicles. At last, each vehicle plans its speed profile to meet the received passing sequence by V2I. The simulation results show that each vehicle can finish the entire travel trip with a near free flow speed in the proposed method.
Crossroads Vertical Speed Control Devices: Suggestion from Observation drboon
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Strategic Management in Dynamic Environments MGMT 690Beginning D.docxflorriezhamphrey3065
Strategic Management in Dynamic Environments MGMT 690
Beginning Development of Global Strategies
3-4 Pages
Mike, one of the marketing strategists on your team, stops at your office door wanting to talk. “We use fabrics that are made domestically; however, there are issues with using these same fabrics globally. There are laws and regulations that prevent us from shipping these fabrics to other countries. This is a huge concern. One of our primary selling points is the consistency of quality of our product.”
You confirm Mike’s concern, “That’s an excellent point,” you say. “Now you’ve just given yourself and our team more work for the presentation. I’m sure that will come up. One of the board members used to run a textile plant in China.”
Mike nods his head in agreement. “I imagine textiles will not be the only resource concern,” he says.
Consider the following in your response:
· Why should resources be a concern in a global strategy?
· What resources may be a concern in the country you selected?
· How will this impact the decision to move to the country that you selected?
· How will this impact your competitive strategy in your global market?
MUST USE ACADEMIC SOURCES SUCH AS GOOGLE SCHOLAR, GOVERNMENT, SCHOLARLY REVIEWED ETC.
European Journal of Operational Research 241 (2015) 502–512
Contents lists available at ScienceDirect
European Journal of Operational Research
journal homepage: www.elsevier.com/locate/ejor
Innovative Applications of O.R.
Solving air traffic conflict problems via local continuous optimization
Clément Peyronne a,∗, Andrew R. Conn b, Marcel Mongeau c,d, Daniel Delahaye c,d
a Capgemini, 15 av. du Dr Maurice Grynfogel, 31000 Toulouse, France
b IBM, T.J. Watson Research Center, P.O. Box 218, Yorktown Heights, NY 10598, USA
c ENAC, MAIAA, F-31055 Toulouse, France
d Université de Toulouse, IMT, F-31400 Toulouse, France
a r t i c l e i n f o
Article history:
Received 29 August 2012
Accepted 31 August 2014
Available online 28 September 2014
Keywords:
Air traffic conflict problem
B-splines
Continuous optimization
Genetic algorithms
Semi-infinite programming
a b s t r a c t
This paper first introduces an original trajectory model using B-splines and a new semi-infinite program-
ming formulation of the separation constraint involved in air traffic conflict problems. A new continuous
optimization formulation of the tactical conflict-resolution problem is then proposed. It involves very few
optimization variables in that one needs only one optimization variable to determine each aircraft trajec-
tory. Encouraging numerical experiments show that this approach is viable on realistic test problems. Not
only does one not need to rely on the traditional, discretized, combinatorial optimization approaches to this
problem, but, moreover, local continuous optimization methods, which require relatively fewer iterations
and thereby fewer costly function evaluations, are shown to improve the performance of .
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PROPOSED INTELLIGENT TRANSPORT SYSTEM DEPLOYMENTS IN KAJANG CITY664601
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The document discusses traffic stream models. It describes two classes of traffic models: macroscopic models that examine average behaviors like density and speed, and microscopic models that examine individual behaviors like car-following models. The car-following model assumes cars cannot pass and a car's acceleration depends on the headway distance and speed difference of the car in front. Conservation laws state that the number of cars in a highway segment remains constant over time. Greenshield's model relates traffic speed to density, with free flow at low density and zero speed at maximum density. The document outlines concepts like flow rate, spacing, headway, density and speed-flow-density relationships.
This document summarizes a study of traffic flow characteristics for heterogeneous traffic in India. Speed, flow, and time headway data were collected from a six-lane urban road and analyzed. Headways between different vehicle combinations were found to best fit several statistical distributions. Speed-flow curves were plotted to determine the speed at which optimal flow occurs, though the study was limited by only using one hour of data. The results provide insight into modeling headways and understanding traffic flow in heterogeneous, mixed traffic conditions.
This document presents a mathematical model for determining the minimum overtaking sight distance (OSDm) required for an ascending vehicle to safely pass another slower vehicle on a single lane highway with an incline. It defines sight distance, stopping sight distance, perception-reaction time and derives equations to calculate the reaction distance (d1), overtaking distance (d2), vehicle travel distance during overtaking (d3), and total minimum OSDm based on vehicle characteristics, road geometry, and coefficients of friction. The safe overtaking zone is defined as 3 times the minimum OSDm. The model accounts for effects of slope angle and aims to satisfy laws of mechanics for overtaking maneuvers on inclined two-way single lane highways.
INTELLIGENT TRANSPORTATION SYSTEM BASED TRAFFIC CONGESTION MODELLING FOR URBA...civej
This study attempts to make use of traffic behaviour on the aggregate level to estimate congestion on urban arterial and sub-arterial roads of a city exhibiting heterogeneous traffic conditions by breaking the route into independent segments and approximating the origin-destination based traffic flow behaviour of the segments. The expected travel time in making a trip is modelled against sectional traffic characteristics (flow and speed) at origin and destination points of road segments, and roadway and segment traffic characteristics such as diversion routes are also tried in accounting for travel time. Predicted travel time is then used along with free flow time to determine the state of congestion on the segments using a congestion
index (CI). A development of this kind may help in understanding traffic and congestion behaviour practically using easily accessible inputs, limited only to the nodes, and help in improving road network planning and management.
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A Comparative Study On Swarm-Based Algorithms To Solve The Stochastic Optimiz...Monica Waters
This document describes a study that compares swarm-based algorithms (particle swarm optimization and glowworm swarm optimization) for solving a stochastic optimization problem in container terminal design. The goal is to minimize total container passage time by determining the optimal number of equipment (e.g. cranes, trucks) needed considering uncertainties like demand variations. A simulation model using Monte Carlo methods captures the stochastic nature. Results show the proposed glowworm swarm optimization approach performs better than particle swarm optimization algorithms in finding feasible solutions to the complex optimization problem involving numerous combinations of decisions under uncertainty.
This document discusses a study that aimed to determine the optimal number of closed lanes in work zones on divided rural highways in Egypt to minimize user costs. The study used the World Bank's HDM-4 software to evaluate operating speed, travel time costs, vehicle operating costs, and national income loss under various work zone configurations on 8-lane, 6-lane and 4-lane highways. Field data was also collected and analyzed to verify the HDM-4 results. The findings recommended that vehicle operating costs decrease when more lanes are closed if operating speeds are between 50-0 kph, but increase if speeds are between 50-free flow kph. Travel time costs increase and operating speeds decrease with more closed lanes.
Problem #4 (20 points) a.A bus route having seven scheduled stops h.pdfarihantcomputersddn
Problem #4 (20 points) a.A bus route having seven scheduled stops has the following number of
passengers alighting and boarding the bus Sto Alighting 0 Boarding 20 0 per passenger 1.8
seconds and boarding Passengers board and alight through the front door. Alighting time p time
per passenger 3 seconds. Compute the dwell time at each stop and the total dwell time. Assume
the clearance ime 5 seconds. Briefly describe the four categories of transit system characteristics.
c. Briefly describe the various transit modes of transportation End of Problem #4 Problemi #5
(20 points) Transportation Engineering is a multidisciplinary area of study. It is a profession that
carries distinct societal responsibilities. What would a comprehensive training include? Provide
examples of each training tem a) b) c) d) Explain the difference between direct elasticity and
cross elasticity. Give one example of each What does CBD mean? Give an example of a CBD A
transportation network having the following characteristics Travel time (minutes) between nodes
Nodes From 10 10 10 0 16 12 Each node represents an activity center, and each link represents
travel time in minutes. Draw a link/node diagrams for the travel times and distances, if the
average travel speed on all links is 30 miles per hour End of Problem #5
Solution
4. (a). There are 2 ways in general to model the dwell time at a particular stop which depends on
whether the boarding and alighting processes are sequential or simultaneous. Assuming in the
question given that sequential boarding and alighting takes place since only one front door is
available for flow of passengers:
Dw = a * A + b*B + td ;
where
A and B are the number of boarding and alighting passengers respectively
a and b are time intervals for boarding and alighting per passenger.
td is the average clearance time for opening and closing the doors.
Here a= 3 sec, b=1.8sec
Therefore, at Stop 1:
Dw1 = 3*20 + 1.8*0 + 5 = 65 sec
Stop 2: Dw2 = 3*5 + 1.8*3 + 5 = 25.4 sec
Stop 3: Dw3 = 3*7 + 1.8*5 + 5 = 35 sec
Stop 4: Dw4 = 3*3 + 1.8*6 + 5 = 24.8 sec
Stop 5: Dw5 = 3*4 + 1.8*8 + 5 = 31.4 sec
Stop 6: Dw6 = 3*2 + 1.8*7 + 5 = 23.6 sec
Stop 7: Dw7 = 3*0 + 1.8*12 + 5 = 26.6 sec
Total dwell time= 231.8 seconds
(b). Transit system characteristics can be classified into four main categories:
i. System performance elements: Contains entire set of physical performance related elements
which decides the raw efficiency of the central system employed as the primary functional core
unit of the transit model. This includes Service frequency, operating speed, reliability and safety
measures and line and productive capacities.
ii. Level of Service (LOS) is an important service parameter that affects the users drastically due
to differential change in its delivery. It is a simple basic most powerful characteristic that can
attract the users or provide bad experiences to them if miniscule error occurs in provider’s
implementation. The factors that affect LOS are performance.
IRJET- Detailed Survey & Analysis of a Traffic System on Mid Block Sectio...IRJET Journal
This document summarizes a study on analyzing traffic flow on mid-block sections and intersections in Khargone city, India. The study aims to understand vehicle-pedestrian interactions through field observations of multiple intersections and mid-block crossings. Different locations within the city were selected to see if pedestrian flow fundamentals diagrams varied between places. Manual counts and surveys were conducted using tally sheets. Automatic counts were also collected using pneumatic tubes and inductive loops embedded in the road. The study found the pedestrian fundamental diagrams did vary between different locations in Khargone city.
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2. 661Joewono Prasetijo et al. / Procedia - Social and Behavioral Sciences 138 (2014) 660 – 670
requires traffic control. It is regulated with stop signs, traffic lights, and roundabout. The common type of
intersection is the unsignalized intersection, which is used to regulate low volume of traffic flow between the major
and minor streets. The Two-Way Stop-Controlled (TWSC) and All-Way Stop-Controlled (AWSC) are among the
types of operation for unsignalized intersection. Unsignalized intersection operates without positive indication or
control to the driver (Troutbeck and Brilon, 1992). It depends on the driver’s decision to take the right opportunity
to enter the major street.
The gap-acceptance method assumed the drivers to comply with the priority of right-of-way of each traffic
stream. However, the gap-acceptance method has a few drawbacks (Brilon and Wu, 2002). It does not take driver
behavior into consideration, particularly on the compliance with priority rules. Forced gap caused by aggressive
driver, and polite behavior of drivers that purposely provide gap clearly are not in accordance to the rules of priority.
The situation is worsened by heterogeneous traffic, a mix of motorized and non-motorized modes (Prasetijo, 2007;
Prasetijo et al., 2011). Therefore, the conflict method has been developed to overcome the problems in the gap-
acceptance method. The conflict method simplifies the intersection capacity analysis. It improves the reliability of
the techniques used to assess the condition and design of unsignalized intersection.
The key parameter for the conflict method is the occupation time, tB,q. It is the time spent by a vehicle for
occupying the conflict area. The term tB,q,m and tB,q,i was used (Brilon and Wu, 2002) and implemented for non-
priority intersections (Prasetijo et al., 2012), alternatively to describe the occupancy time of vehicles at the conflict
area. Another parameter to be considered in the conflict method is the blocking time of conflict area due to
approaching vehicle, tB,a. Thus, the objectives of this study are to determine the occupation and approaching time of
vehicle, and to evaluate the performance of different design of unsignalized intersection based on the occupation
time values.
2. Conflict Technique Approach
Two T-intersections in Parit Buntar, Perak has been selected for this study. Parit Buntar Town intersection is
labelled as Intersection A, while Jalan Sekolah intersection shall be Intersection B. Both intersections have a typical
layout with the combination of shared lane and flared approach. Surveillance equipment is used during field
observation. The video captured contains information such as the traffic volume for each stream, the time taken by
the vehicles to occupy the conflict area, and the approaching time of major vehicles. Traffic count is conducted
beforehand to identify the peak hour for suitable observation period.
A conflict group consists of several movements that cross the same area within an intersection (Brilon and Wu,
2002). Generally, the capacity of a minor stream is expressed by Equation (1). On the other hand, the proportion of
time spent by discharging vehicle in the conflict area is calculated using Equation (2). The conflict area can be
blocked by the approaching vehicles of higher priority. The proportion of time the approaching vehicle is blocking
the conflict area is defined by Equation (3).
Cm = Cmax,m ∙ p0 (1)
Where:
Cm = Capacity of movement m [veh/h]
Cmax,m = Maximum possible capacity of movement m [veh/h]
=
mqBt ,,
3600
tB,q,m = Occupation time of movement m [s]
p0 = Pr(no blockage) [-]
Bq,m =
3600
. ,, mqBm tQ
(2)
Where:
Qm = Traffic demand of movement m [veh/h]
tB,q,m = Occupation time of movement m [s]
3. 662 Joewono Prasetijo et al. / Procedia - Social and Behavioral Sciences 138 (2014) 660 – 670
Bq,m = Proportion of occupancy by discharging vehicle m [-]
with the restriction of Qm ∙ tB,q,m ≤ 3600
Ba,m = , ,.
3600
m B a mQ t
(3)
Where:
tB,a,m = Approaching time of movement m [s]
Ba,m = Proportion of period the conflict area is blocked by approaching
vehicle m
[-]
The probability p0 can also be computed as the product of the probability whereby the conflict area is not
occupied by standing or discharging major vehicles, and the probability that the approaching major vehicles are not
occupying the conflict area. It is computed using Equation (4). This study focuses on the T-intersection, shown in
Figure 1. The capacity of each movement is computed using Equation (5) till Equation (10).
Fig. 1. Conflict groups at a T-intersection
p0 = p0,q ∙ p0,a (4)
Where:
p0 = Pr(no blockage) [-]
p0,q = Pr(no discharging of major stream vehicles [-]
p0,a = Pr(no approaching major vehicles) [-]
and
C2 = Cmax,2 (5)
C3 = Cmax,3∙ (1-Bq,5)∙(1-Bq,4)∙exp[-(Ba,5+Ba,4)] (6)
C4 = Cmax,4 (7)
C5 = Cmax,5 (8)
C7 = Cmax,7∙ (1-Bq,5)∙exp[-(Ba,5)] (9)
4. 663Joewono Prasetijo et al. / Procedia - Social and Behavioral Sciences 138 (2014) 660 – 670
C9 = Cmax,9∙ [1-(Bq,5+Bq,3)]∙(1-Bq,2)∙exp[-(Ba,5+Ba,3+Bq,2)] (10)
After the actual capacity is determined, the effective occupation time is calculated using Equation (11). A
comparison can be made between the capacity values measured using the conflict method and the HCM 2000 for
result validation. In HCM 2000, the performance of unsignalized intersection is indicated by the control delay,
which is also applicable for the conflict method (Brilon and Miltner, 2005)
tB,q,m* =
mC
3600
(11)
Where:
tB,q,m* = Effective occupation time of movement m [s]
Cm = Capacity of movement m [veh/h]
3. Occupation Time of Vehicular Movements
The orientation of vehicular movements at Intersection A is shown in Figure 2. Figure 3 depicts vehicular
movements at Intersection B.
Fig. 2. Vehicular movements of intersection A
5. 664 Joewono Prasetijo et al. / Procedia - Social and Behavioral Sciences 138 (2014) 660 – 670
Fig. 3. Vehicular movements of intersection B with flare
Intersection A – no flare
Table 1 shows the occupation time for each movement at Intersection A. South left-turning vehicles have the
lowest tB,q for turning movement. The travel distance between the south and west approaches is the shortest. The
vehicles are able to cross the intersection faster. As a result, the occupation times of these turning streams are
reduced.
Table 1. Occupation time of vehicular movement at intersection A
Vehicle movement Occupation time (s)
South Left Turn 2.02
South Right Turn 4.85
West Right Turn 2.44
West Through (Bottom) 1.96
West Through (Top) 1.83
East Through 1.94
East Left Turn 1.64
The west right-turning movement has conflict with two movements of higher priority. Being the high-priority
movement itself, the west right-turning vehicles have a small tB,q. However, the occupation time of this vehicular
stream is higher than the south left-turning movement due to the longer travel distance between approaches. It
indicates the high travel speed of the west right-turning vehicles when entering the south approach. The highest tB,q
is achieved by the south right-turning movement. This movement has the lowest priority among other vehicular
movements. The conflict areas contain three major streams of different directions. The south right-turning
movement also has the farthest travel distance to be covered in the conflict area.
The bottom lane of the west through movement is shared with the west right-turning movement. The observation
of Intersection A showed the tendency of the south drivers to commit forced gap when entering the intersection.
Drivers using the west through lane are cautious of the incoming vehicles from the south approach. The tB,q of the
bottom lane indicates lower vehicular speed, contrary to the top lane of the west through movement. The top lane of
the west through movement is less affected by conflicting vehicles. This lane is located away from the conflict area.
Apparently, the vehicles can travel at higher speed. However, the tB,q of both lanes of the west through movement is
almost equal. The east through movement is located next to the west through bottom lane. Both vehicular streams
6. 665Joewono Prasetijo et al. / Procedia - Social and Behavioral Sciences 138 (2014) 660 – 670
are in the same conflict group. Thus, their occupation times are comparable. On the other hand, the east left-turning
movement has the lowest tB,q of all movements. This movement has the highest priority and the shortest crossing
distance.
Intersection B – with flare
Intersection B introduce flare lane/channelized to improve its performance, especially on turning movements.
Therefore, the west right turning vehicles have a shorter distance to cross the conflict area. On the other hand, the
south left turning vehicles have a separate lane for left turn manoeuvre. However, the occupation times of both
vehicular streams are nearly equivalent, as shown in Table 2. Apparently, they are blocked by the same movement
from the east approach.
Table 2. Occupation time of vehicular movement at intersection B
Vehicular movement Occupation time (s)
South Left Turn 2.52
South Right Turn 4.42
West Right Turn 2.58
West Through (Bottom) 1.35
West Through (Top) 1.29
East Through 1 1.12
East Through 2 1.20
East Left Turn 2.00
The tB,q of the south left turn movement is more than the occupation time of the same movement at Intersection A.
The larger conflict area at the west approach of Intersection B is the cause of increased tB,q for the south left-turning
movement. The channelization of traffic streams at Intersection B has no influence on the occupation time of the
west right-turning vehicles. The value of its tB,q is almost similar to the west right-turning movement of Intersection
A.
It is evident that the south right turn movement has the highest tB,q. Compared to Intersection A, the
channelization of Intersection B has reduced the occupation time of its movements by a small margin. Nonetheless,
the south right-turning movements of both intersections are comparable due to similar traffic conflicts. The west
approach has two lanes. The bottom through lane is shared with the right turn lane. However, the difference of tB,q
values between the top and bottom lanes of the west through movement is insignificant. The shared lane does not
impede the movement of the west through bottom vehicles. Similar result is achieved for Intersection A. It is due to
the unsaturated condition of both intersections.
Intersection B has a divided south approach. The left turn and right turn of the south approach is separated to
increase the capacity of both movements. This condition has created a space in between the turning lanes.
Consequently, two streams of east through vehicles are produced. In the east approach, the second through
movement has higher tB,q than its first through stream due to larger conflict area. It is also caused by the continuous
deceleration of vehicles after leaving the intersection. The occupation times of both through streams are low due to
the short travel distance between approaches. The east left-turning movement is supposed to produce small
occupation time. In the case of Intersection B, large conflict area has caused this traffic stream to produce a higher
tB,q, although it has a separate lane. Besides this, drivers are cautious of the incoming vehicles from the west
approach, which eventually reduces their vehicular speed.
4. Capacity of Vehicular Movements
Intersection A – no flare
Figure 4 shows the volume and capacity of the turning movements at Intersection A. The capacity values of these
movements are expected to be lower than the major stream capacities. It is due to the impeding effect by major
vehicular movements. The subject vehicles have to cross the conflict areas when entering the intersection. The
7. 666 Joewono Prasetijo et al. / Procedia - Social and Behavioral Sciences 138 (2014) 660 – 670
volume and capacity of major movements at Intersection A are given in Figure 4. The south left turn stream has the
highest capacity among other turning movements, which is the outcome of having a separate lane. The recorded
occupation time of this movement is also the lowest. As a result, the south left-turning lane is able to cater more
vehicles.
There are three impeding vehicular streams that are blocking the south right turn movement; as a result its
occupation time is the highest among other turning movements. Due to the blocking major movements and high tB,q,
the south right-turning movement has the lowest capacity. The west right turn movement has similar priority with
the south left turn stream. However, there is a vast difference between its volume and capacity values.
The major movements have absolute priority over the turning streams. Conflict areas do not obstruct the major
street vehicles. In addition, the major streams have low occupation time. Therefore, they are expected to have
higher capacity. It is evident from Figure 5. The east left-turning stream has the highest capacity due to the exclusive
lane. It provided more space for the vehicles, with reduced traffic conflict. The shared lane condition of the west
through bottom movement has minimal impact on its capacity.
Fig. 4. Volume and capacity of turning movements at intersection A
Fig. 5. Volume and capacity of major movements at intersection A
161 183
324
171
1833
1965
1857
2190
0
500
1000
1500
2000
2500
West
Through
(Bottom)
West
Through
(Top)
East Through East Left
Turn
Vehicular Movement
TrafficFlow(veh/h)
Volume
Capacity
391
208
131
1785
742
1478
0
200
400
600
800
1000
1200
1400
1600
1800
2000
South Left Turn South Right Turn West Right Turn
Vehicular Movement
TrafficFlow(veh/h)
Volume
Capacity
8. 667Joewono Prasetijo et al. / Procedia - Social and Behavioral Sciences 138 (2014) 660 – 670
Intersection B – with flare/channelized
In Intersection A, the capacity difference between the south left turn and the west right turn streams is noticeable.
However, the volume and capacity of both movements of Intersection B are almost similar. The site investigation
has revealed that the south approach is leading towards schools. During peak hour, the traffic movements between
the south and west approaches have produced such result, as shown in Figure 6.
The south right turn stream is predicted to have the lowest capacity. In the case of Intersection B, there is
improvement over the same movement as compared to Intersection A. The intersection area is smaller, thus reducing
the travel distance from the south approach to the east approach.
For west approach, although the bottom lane is shared, the capacity difference between west through and right
turn movements is small. The traffic volume of the west through bottom lane is the lowest. This lane is mostly
occupied by the west right-turning vehicles. Consequently, the drivers prefer the top lane of the west approach for
through movement. Thus, the traffic volume at the top lane is more than the bottom lane, as shown in Figure 7.
The east through stream is analyzed separately due to the geometric condition of Intersection B. In this case, the
minimum capacity value is selected for the east through movement. The second through movement has less capacity
than the first through stream because of its larger tB,q. Therefore, the second capacity value of 2997 veh/h is chosen
to determine the control delay of the east through movement.
The least capacity of major movement is achieved by the east left-turning stream. It is due to the larger conflict
area. Similar to the west right-turning movement, the drivers of the east left turn stream are being cautious of the
incoming vehicles from the west approach.
Fig. 6. Volume and capacity of turning movements at intersection B
9. 668 Joewono Prasetijo et al. / Procedia - Social and Behavioral Sciences 138 (2014) 660 – 670
Fig. 7. Volume and capacity of major movements at intersection B
5. Results on Capacity Comparison of Turning Movements
Intersection A – no flare
The capacity comparison between the conflict method and the HCM 2000 procedures for turning movements is
shown in Figure 8. The field data is obtained from data collection on site. The given data is based on the parameter
values stated in the HCM 2000 (TRB, 2000).
Apart from the HCM 2000 using given data, the capacity values of the vehicular movements at the south
approach are almost similar. However, the west right turn stream capacity has noticeable difference between each
method.
Fig. 8. Capacity comparison of turning movements at intersection A
Intersection B – with flare/channelized
28
477 490 490
93
2664 2800
3223
2997
1799
0
500
1000
1500
2000
2500
3000
3500
West
Through
(Bottom)
East
Through
1
East Left
Turn
Vehicular Movement
TrafficFlow(veh/h)
Volume
Capacity
1785
742
1478
1799
739
986
556
205
802
0
200
400
600
800
1000
1200
1400
1600
1800
2000
South Left
Turn
South Right
Turn
West Right
Turn
Vehicular Movement
Capacity(veh/h)
Conflict
Method
HCM 2000
(Field Data)
HCM 2000
(Given Data)
10. 669Joewono Prasetijo et al. / Procedia - Social and Behavioral Sciences 138 (2014) 660 – 670
As in Intersection A, the HCM 2000 method using given data has underestimated the turning stream capacity
values, according to Figure 9. The south right-turning movement has the worst capacity of 86 veh/h, which is
illogical. This anomaly is likely due to software issue during data analysis. The tB,q and tc,field values obtained with
both methods are compared in Table 6. The occupation time and the critical gap are shown to be inversely
proportional to the capacity, except for the south right turn movement. Small value of tB,q indicates that more
vehicles can cross the conflict area, thus increasing the capacity. Similarly, the capacity values also increase when
vehicles have small critical gap.
1429
815
13961380
636
1187
440
86
879
0
200
400
600
800
1000
1200
1400
1600
South Left
Turn
South Right
Turn
West Right
Turn
Vehicular Movement
Capacity(veh/h)
Conflict
Method
HCM 2000
(Field Data)
HCM 2000
(Given Data)
Fig. 9. Capacity comparison of turning movements at intersection B
6. Conclusions
Several methods have been developed to analyze the unsignalized intersection. Among them, the gap-acceptance
method is the dominant approach. It is adopted by many countries in their capacity manuals. The gap-acceptance
method has a simple concept. It depends on the driver’s decision to accept or reject a gap before making any
vehicular manoeuvre.
However, there are drawbacks to this approach, such as non-compliance to the priority rules. Efforts have been
made to improve the reliability of the unsignalized intersection analysis. Conflict method was proposed to assist the
current methods available. It is based on the interaction between vehicular movements and geometric design that
created conflict areas in the intersection. According to the results from the data analysis, the following conclusions
have been made:
(a) The occupation time is inversely proportional with the capacity of the vehicular movement. Small
occupation time indicates that more vehicles are able to cross the conflict area in a given time period, and vice-
versa. It can also provide an estimation of the vehicular speed when they are crossing the intersection.
(b) Long duration of occupation time is achieved due to slow-moving vehicles, large intersection area, and
multiple blocking major streams. It will increase the delay of the vehicular movement, thus degrading its LOS.
(c) The exclusive lane for turning movement is capable to reduce the delay of vehicular stream. However, it still
depends on the vehicular speed, and the traffic volume. On the other hand, the shared lane does not always
impede the movement of turning streams, provided that the traffic volume is low.
11. 670 Joewono Prasetijo et al. / Procedia - Social and Behavioral Sciences 138 (2014) 660 – 670
Acknowledgement
The authors would like to express their sincere appreciation to the Faculty of Civil and Environmental Engineering
(FKAAS), University Tun Hussein Onn Malaysia (UTHM) for facilitating and supporting this research to be
conducted and published. Appreciation also goes to the Office of Research and Innovation UTHM for the technical
support.
References
Brilon, W., & Wu, N. (2002). Unsignalized Intersections-A Third Method for Analysis. In Transportation and
Traffic Theory in the 21st Century. Proceedings of the 15th International Symposium on Transportation and Traffic
Theory.
Brilon, W., & Miltner, T. (2005). Capacity at intersections without traffic signals. Transportation Research Record:
Journal of the Transportation Research Board, 1920(1), 32-40.
Gattis, J. L., & Low, S. T. (1998). Gap acceptance at non-standard stop-controlled intersections (No. MBTC FR
1059,). University of Arkansas, Mack-Blackwell National Rural Transportation Study Center.
Highway Capacity Manual. (2000). Transportation Research Board. National Research Council, Washington, D.C.
Highway Capacity Manual. (2010). Transportation Research Board. National Research Council, Washington, D.C.
Li, H., Tian, Z., & Deng, W. (2011). Capacity of TWSC Intersection with Multilane Approaches. Procedia-Social
and Behavioral Sciences, 16, 664-675.
Prasetijo, J., Pour, M. H., & Ghadiri, S. M. R. (2011). Capacity of Unsignalized Intersections under Mixed Traffic
Conditions. Procedia-Social and Behavioral Sciences, 16, 676-685.
Prasetijo, J., & Halimshah, A. (2012). Effectiveness of Capacity Estimation under Mixed Traffic Conditions.
Compendium of 91st Transportation Research Board Annual Meeting (TRB), Washington, D.C., U.S.A.
Prasetijo, J., (2007). Capacity and Traffic Performance of Unsignalized Intersection under Mixed Traffic Conditions.
Ph.D Thesis, Ruhr-University Bochum.
Troutbeck, R. J., and Brilon, W., (1992). Unsignalized Intersection Theory. Turner-Fairbank Highway Research
Center, Virginia.
Wu, N. (2000, June). Capacity at All-Way Stop-Controlled and First-In-First-Out Intersections. In Proceedings of
the 4th International Symposium on Highway Capacity, Hawaii, Transportation Research Circular E-C018.