scholarly journals Designing Vehicle Turning Restrictions Based on the Dual Graph Technique

2017 ◽  
Vol 2017 ◽  
pp. 1-11
Author(s):  
Lihui Zhang ◽  
Hongsheng Qi ◽  
Dianhai Wang ◽  
Zhong Wang ◽  
Jian Yang
Keyword(s):  
Travel Time ◽  
Heuristic Algorithm ◽  
Design Problem ◽  
Transportation Network ◽  
Dual Graph ◽  
User Equilibrium ◽  
Total System ◽  
Nonlinear Constraints ◽  
Dual Transformation

This paper investigates the turning restriction design problem that optimizes the turning restriction locations so as to minimize the total system travel time under the assumption of asymmetric user equilibrium. We first transform a transportation network into a dual graph, where traffic turning movements are explicitly modeled as dual links. The dual transformation allows us to derive a link-based formulation for the turning restriction design problem. Asymmetric user equilibrium is incorporated in the model as a set of nonlinear constraints. A dual-based heuristic algorithm is employed to solve the problem, by sequentially solving a relaxed turning restriction design problem and a design updating problem.

scholarly journals An MPCC Formulation and Its Smooth Solution Algorithm for Continuous Network Design Problem

2017 ◽  
Vol 29 (6) ◽  
pp. 569-580
Author(s):  
Guangmin Wang ◽  
Junwei Yu ◽  
Shubin Li
Keyword(s):  
Network Design ◽  
Design Problem ◽  
Transportation Network ◽  
User Equilibrium ◽  
Network Design Problem ◽  
Total System ◽  
Complementarity Constraints ◽  
Mathematical Programs ◽  
Investment Cost ◽  
Non Linear

Continuous network design problem (CNDP) is searching for a transportation network configuration to minimize the sum of the total system travel time and the investment cost of link capacity expansions by considering that the travellers follow a traditional Wardrop user equilibrium (UE) to choose their routes. In this paper, the CNDP model can be formulated as mathematical programs with complementarity constraints (MPCC) by describing UE as a non-linear complementarity problem (NCP). To address the difficulty resulting from complementarity constraints in MPCC, they are substituted by the Fischer-Burmeister (FB) function, which can be smoothed by the introduction of the smoothing parameter. Therefore, the MPCC can be transformed into a well-behaved non-linear program (NLP) by replacing the complementarity constraints with a smooth equation. Consequently, the solver such as LINDOGLOBAL in GAMS can be used to solve the smooth approximate NLP to obtain the solution to MPCC for modelling CNDP. The numerical experiments on the example from the literature demonstrate that the proposed algorithm is feasible.

scholarly journals Application of Bat Algorithm for Transport Network Design Problem

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Sweta Srivastava ◽  
Sudip Kumar Sahana
Keyword(s):  
Network Design ◽  
Travel Time ◽  
Design Problem ◽  
Wait Time ◽  
Development Planning ◽  
User Equilibrium ◽  
Transport Network ◽  
Network Design Problem ◽  
Soft Computing Techniques ◽  
Transport Network Design

The requirement of the road services and transportation network development planning came into existence with the development of civilization. In the modern urban transport scenario with the forever mounting amount of vehicles, it is very much essential to tackle network congestion and to minimize the travel time. This work is based on determining the optimal wait time at traffic signals for the microscopic discrete model. The problem is formulated as a bilevel model. The upper layer optimizes the travel time by reducing the wait time at traffic signal and the lower layer solves the stochastic user equilibrium. Soft computing techniques like Genetic Algorithms, Ant Colony Optimization, and many other biologically inspired techniques prove to give good results for bilevel problems. Here this work uses Bat Intelligence to solve the transport network design problem. The results are compared with the existing techniques.

scholarly journals Optimal Signal Design for Mixed Equilibrium Networks with Autonomous and Regular Vehicles

2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Nan Jiang
Keyword(s):  
Autonomous Vehicles ◽  
Design Problem ◽  
Control Strategies ◽  
Transportation Network ◽  
Bilevel Optimization ◽  
User Equilibrium ◽  
Signal Design ◽  
Level Model ◽  
Mixed Equilibrium ◽  
Mixed Networks

A signal design problem is studied for efficiently managing autonomous vehicles (AVs) and regular vehicles (RVs) simultaneously in transportation networks. AVs and RVs move on separate lanes and two types of vehicles share the green times at the same intersections. The signal design problem is formulated as a bilevel program. The lower-level model describes a mixed equilibrium where autonomous vehicles follow the Cournot-Nash (CN) principle and RVs follow the user equilibrium (UE) principle. In the upper-level model, signal timings are optimized at signalized intersections to allocate appropriate green times to both autonomous and RVs to minimize system travel cost. The sensitivity analysis based method is used to solve the bilevel optimization model. Various signal control strategies are evaluated through numerical examples and some insightful findings are obtained. It was found that the number of phases at intersections should be reduced for the optimal control of the AVs and RVs in the mixed networks. More importantly, incorporating AVs into the transportation network would improve the system performance due to the value of AV technologies in reducing random delays at intersections. Meanwhile, travelers prefer to choose AVs when the networks turn to be congested.

scholarly journals On the Price of Satisficing in Network User Equilibria

2020 ◽  
Vol 54 (6) ◽  
pp. 1555-1570
Author(s):  
Mahdi Takalloo ◽  
Changhyun Kwon
Keyword(s):  
Travel Time ◽  
Transportation Networks ◽  
User Equilibrium ◽  
Decision Makers ◽  
Total System ◽  
Travel Times ◽  
Traffic Patterns ◽  
Worst Case ◽  
Traffic Pattern

When network users are satisficing decision makers, the resulting traffic pattern attains a satisficing user equilibrium, which may deviate from the (perfectly rational) user equilibrium. In a satisficing user equilibrium traffic pattern, the total system travel time can be worse than in the case of the perfectly rational user equilibrium. We show how bad the worst-case satisficing user equilibrium traffic pattern can be compared with the perfectly rational user equilibrium. We call the ratio between the total system travel times of the two traffic patterns the price of satisficing, for which we provide an analytical bound. We compare the analytical bound with numerical bounds for several transportation networks.

Bilevel Formulation for Optimal Traffic-Information Dissemination

2003 ◽  
Vol 1836 (1) ◽  
pp. 21-28 ◽  
Author(s):  
Fan Yang ◽  
Henry X. Liu ◽  
Rachel R. He ◽  
Xuegang Ban ◽  
Bin Ran
Keyword(s):  
Travel Time ◽  
System Performance ◽  
Information Dissemination ◽  
Transportation Network ◽  
Information Services ◽  
Traffic Information ◽  
Total System ◽  
Dynamic Traffic ◽  
Trade Offs ◽  
Upper Level

With the fast-growing telematics market and maturing traffic-information services, telematics devices provide a feasible means with which to manage traffic more efficiently. The provision of traffic information to travelers usually involves different parties that have distinctive objectives: travelers are concerned with benefits of travel-time savings at an affordable service charge, private information service providers (ISPs) seek to provide marketable information services from which they can derive a profit, and traffic management centers (TMCs) have the responsibility to maintain and improve system performance, especially to minimize the total system travel time. How transportation system managers can analyze the trade-offs among these objectives and adjust this new traffic-information flow diagram to improve system performance remains an open question. The trade-offs needed among the conflicting multiple objectives of different parties are studied, and traffic system performance is analyzed. The complex traffic network is formulated as a bilevel program. The upper level can be formulated by using various objective functions, such as the objectives for ISP and TMC. The lower level is a multiclass dynamic traffic-assignment model, which determines dynamic traffic flows in the network by considering the information dissemination strategies provided by the upper-level model. Numerical results of a small network are provided to illustrate the behavior of this model, and they prove that when there is congestion in the dynamic transportation network, appropriate subscribed rates benefit both all travelers and system performance, while the ISPs’ information influences little without congestion in the transportation network.

scholarly journals A Transportation Network Paradox: Consideration of Travel Time and Health Damage due to Pollution

2020 ◽  
Vol 12 (19) ◽  
pp. 8107
Author(s):  
Zhaolin Cheng ◽  
Laijun Zhao ◽  
Huiyong Li
Keyword(s):  
Air Pollution ◽  
Travel Time ◽  
Travel Demand ◽  
Transportation Network ◽  
Flow Distribution ◽  
System Optimization ◽  
User Equilibrium ◽  
Braess Paradox ◽  
Health Damage ◽  
Route Choices

In cities with serious air pollution, travel time and health damage significantly affect route choice by travelers (e.g., motorcycle and scooter drivers). Consequently, the classical Braess paradox is no longer realistic because it only considers the traveler’s value of time (VOT). In the current study, we describe a new transportation network paradox that considers both the VOT and the traveler’s perception of pollution damage. To examine the conditions that create the new paradox, we developed a novel method to compute a total comprehensive cost that combines the VOT with health damage. We analyzed the conditions for the new paradox and the system’s performance using a user equilibrium model and system optimization. Furthermore, an improved model is used to analyze how different transport modes influence the Braess paradox. We found that whether the new paradox occurs and the potential improvement of the system’s performance depend on whether the total travel demand falls within critical ranges. The bounds of these ranges depend on the values of the parameters in the function that describes the health damage and the link travel time function. In addition, high health damage significantly affects route choices and traffic flow distribution. This paper presents a new perspective for decision-making by transportation planners and for route choices in cities with serious air pollution.

scholarly journals Stochastic Congestion Pricing among Multiple Regions: Competition and Cooperation

2013 ◽  
Vol 2013 ◽  
pp. 1-11
Author(s):  
Hua Wang ◽  
Wei Mao ◽  
Hu Shao
Keyword(s):  
Social Welfare ◽  
Travel Time ◽  
Demand Uncertainty ◽  
Transportation Network ◽  
Congestion Pricing ◽  
User Equilibrium ◽  
Travel Time Reliability ◽  
Stochastic User Equilibrium ◽  
Multiple Regions ◽  
The Impact

Previous studies of road congestion pricing problem assume that transportation networks are managed by a central administrative authority with an objective of improving the performance of the whole network. In practice, a transportation network may be comprised of multiple independent local regions with relative independent objectives. In this paper, we investigate the cooperative and competitive behaviors among multiple regions in congestion pricing considering stochastic conditions; especially demand uncertainty is taken into account in transportation modelling. The corresponding congestion pricing models are formulated as a bilevel programming problem. In the upper level, congestion pricing model either aims to maximize the regional social welfare in competitive schemes or attempts to maximize the total social welfare of multiple regions in cooperative schemes. In the lower level, travellers are assumed to follow a reliability-based stochastic user equilibrium principle considering risks of late arrival under uncertain conditions. Numerical examples are carried out to compare the effects of different pricing schemes and to analyze the impact of travel time reliability. It is found that cooperative pricing strategy performs better than competitive strategy in improving network performance, and the pricing effects of both schemes are quite sensitive to travel time reliability.

scholarly journals Analysis of Macroscopic Traffic Network Impacted by Structural Damage to Bridges from Earthquakes

2021 ◽  
Vol 11 (7) ◽  
pp. 3226
Author(s):  
Joongmin Cho ◽  
Young-Joo Lee ◽  
Seongkwan Mark Lee ◽  
Ki Han Song ◽  
Wonho Suh
Keyword(s):  
Travel Time ◽  
Structural Damage ◽  
Transportation Network ◽  
Travel Speed ◽  
Urban Traffic ◽  
Total System ◽  
Emergency Situations ◽  
Capacity Loss ◽  
Traffic Capacity ◽  
The Impact

Highway systems play a key role in providing mobility to society, especially during emergency situations, including earthquakes. Bridges in highway systems are susceptible to damage from earthquakes, causing traffic capacity loss leading to a serious impact on surrounding areas. To better prepare for such scenarios, it is important to estimate capacity loss and traffic disruptions from earthquakes. For this purpose, a traffic-capacity-analysisbased methodology was developed to model the performance of a transportation network immediately following an earthquake using a macroscopic multi-level urban traffic planning simulation model EMME4. This method employs the second order linear approximation (SOLA) traffic assignment and calculates total system travel time for various capacity loss scenarios due to bridge damage from earthquakes. It has been applied to Pohang City in Korea to evaluate the performance of traffic networks in various situations. The results indicate a significant increase in travel time and a decrease in travel speed as the intensity of an earthquake increases. However, the impact on traffic volume varies depending on the bridges. It is assumed that the location of the bridges and traffic routing patterns might be the main reason. The results are expected to help estimate the impact on transportation networks when earthquakes cause traffic capacity loss on bridges.

A Heuristic Algorithm for Solving a Large-scale Real-world Territory Design Problem

Omega ◽  
2021 ◽  
pp. 102442
Author(s):  
Lin Zhou ◽  
Lu Zhen ◽  
Roberto Baldacci ◽  
Marco Boschetti ◽  
Ying Dai ◽  
...  
Keyword(s):  
Heuristic Algorithm ◽  
Real World ◽  
Design Problem ◽  
Large Scale ◽  
Territory Design
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