Download or read book Modeling Estimation and Control of Freeway Traffic written by Xiaotian Sun and published by . This book was released on 2005 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Traffic Modeling Estimation and Control for Large scale Congested Urban Networks written by Mohsen Ramezani Ghalenoei and published by . This book was released on 2014 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling Estimation and Control of Traffic written by Dongyan Su and published by . This book was released on 2014 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation studies a series of freeway and arterial traffic modeling, estimation and control methodologies. First, it investigates the Link-Node Cell Transmission Model's (LN-CTM's) ability to model arterial traffic. The LN-CTM is a modification of the cell transmission model developed by Daganzo. The investigation utilizes traffic data collected on an arterial segment in Los Angeles, California, and a link-node cell transmission model, with some adaptations to the arterial traffic, is constructed for the studied location. The simulated flow and the simulation travel time were compared with field measurements to evaluate the modeling accuracy. Second, an algorithm for estimating turning proportions is proposed in this dissertation. The knowledge about turning proportions at street intersections is a frequent input for traffic models, but it is often difficult to measure directly. Compared with previous estimation methods used to solve this problem, the proposed method can be used with only half the detectors employed in the conventional complete detector configuration. The proposed method formulates the estimation problem as a constrained least squares problem, and a recursive solving procedure is given. A simulation study was carried out to demonstrate the accuracy and efficiency of the proposed algorithm. In addition to addressing arterial traffic modeling and estimation problems, this dissertation also studies a freeway traffic control strategy and a freeway and arterial coordinated control strategy. It presents a coordinated control strategy of variable speed limits (VSL) and ramp metering to address freeway congestion caused by weaving effects. In this strategy, variable speed limits are designed to maximize the bottleneck flow, and ramp metering is designed to minimize travel time in a model predictive control frame work. A microscopic simulation based on the I-80 at Emeryville, California was built to evaluate the strategy, and the results showed that the traffic performance was significantly improved . Following the freeway control study, this dissertation discusses the coordinated control of freeways and arterials. In current practice, traffic controls on freeways and on arterials are independent. In order to coordinate these two systems for better performance, a control strategy covering the freeway ramp metering and the signal control at the adjacent intersection is developed. This control strategy uses upstream ALINEA, which is a well-known control algorithm, for ramp metering to locally maximize freeway throughput. For the intersection signal control, the proposed control strategy distributes green splits by taking into account both the available on-ramp space and the demands of all intersection movements. A microscopic simulation of traffic in an arterial intersection with flow discharge to a freeway on-ramp, which is calibrated using the data collected at San Jose, California, is created to evaluate the performance of the proposed control strategy. The results showed that the proposed strategy can reduce intersection delay by 8%, compared to the current field-implemented control strategy. Transportation mobility can be improved not only by traffic management strategies, but also through the deployment of advanced vehicle technologies. This dissertation also investigates the impact of Adaptive Cruise Control (ACC) and Cooperative Adaptive Cruise Control (CACC) on highway capacity. A freeway microscopic traffic simulation model is constructed to evaluate how the freeway lane flow capacity change under different penetration rates of vehicles equipped with either ACC or CACC system. This simulation model is based on a calibrated driver behavioral model and the vehicle dynamics of the ACC and CACC systems. The model also utilizes data collected from a real experiment in which drivers' selections of time gaps are recorded. The simulation shows that highway capacity can be significantly increased when the CACC vehicles reach a moderate to high market penetration, as compared to both regular manually driven vehicles and vehicles equipped with only ACC.

Download or read book Road Traffic Modeling and Management written by Fouzi Harrou and published by Elsevier. This book was released on 2021-10-05 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: Road Traffic Modeling and Management: Using Statistical Monitoring and Deep Learning provides a framework for understanding and enhancing road traffic monitoring and management. The book examines commonly used traffic analysis methodologies as well the emerging methods that use deep learning methods. Other sections discuss how to understand statistical models and machine learning algorithms and how to apply them to traffic modeling, estimation, forecasting and traffic congestion monitoring. Providing both a theoretical framework along with practical technical solutions, this book is ideal for researchers and practitioners who want to improve the performance of intelligent transportation systems. Provides integrated, up-to-date and complete coverage of the key components for intelligent transportation systems: traffic modeling, forecasting, estimation and monitoring Uses methods based on video and time series data for traffic modeling and forecasting Includes case studies, key processes guidance and comparisons of different methodologies

Download or read book Traffic Flow Dynamics written by Martin Treiber and published by Springer Science & Business Media. This book was released on 2012-10-11 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook provides a comprehensive and instructive coverage of vehicular traffic flow dynamics and modeling. It makes this fascinating interdisciplinary topic, which to date was only documented in parts by specialized monographs, accessible to a broad readership. Numerous figures and problems with solutions help the reader to quickly understand and practice the presented concepts. This book is targeted at students of physics and traffic engineering and, more generally, also at students and professionals in computer science, mathematics, and interdisciplinary topics. It also offers material for project work in programming and simulation at college and university level. The main part, after presenting different categories of traffic data, is devoted to a mathematical description of the dynamics of traffic flow, covering macroscopic models which describe traffic in terms of density, as well as microscopic many-particle models in which each particle corresponds to a vehicle and its driver. Focus chapters on traffic instabilities and model calibration/validation present these topics in a novel and systematic way. Finally, the theoretical framework is shown at work in selected applications such as traffic-state and travel-time estimation, intelligent transportation systems, traffic operations management, and a detailed physics-based model for fuel consumption and emissions.

Download or read book Advances in Control Communication Networks and Transportation Systems written by Eyad H. Abed and published by Springer Science & Business Media. This book was released on 2006-09-10 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt: This unified volume is a collection of invited articles on topics presented at the Symposium on Systems, Control, and Networks, held in Berkeley June 5–7, 2005, in honor of Pravin Varaiya on his 65th birthday. Varaiya is an eminent faculty member of the University of California at Berkeley, widely known for his seminal contributions in areas as diverse as stochastic systems, nonlinear and hybrid systems, distributed systems, communication networks, transportation systems, power networks, economics, optimization, and systems education. The book will serve as an excellent resource for practicing and research engineers, applied mathematicians, and graduate students working in such areas as communication networks, sensor networks, transportation systems, control theory, hybrid systems, and applications.

Download or read book A Functional Analysis Framework for Modeling Estimation and Control in Science and Engineering written by H.T. Banks and published by CRC Press. This book was released on 2012-06-18 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Modern Framework Based on Time-Tested MaterialA Functional Analysis Framework for Modeling, Estimation and Control in Science and Engineering presents functional analysis as a tool for understanding and treating distributed parameter systems. Drawing on his extensive research and teaching from the past 20 years, the author explains how functional

Download or read book Freeway Traffic Modelling and Control written by Antonella Ferrara and published by Springer. This book was released on 2018-04-12 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph provides an extended overview of modelling and control approaches for freeway traffic systems, moving from the early methods to the most recent scientific results and field implementations. The concepts of green traffic systems and smart mobility are addressed in the book, since a modern freeway traffic management system should be designed to be sustainable. Future perspectives on freeway traffic control are also analysed and discussed with reference to the most recent technological advancements The most widespread modelling and control techniques for freeway traffic systems are treated with mathematical rigour, but also discussed with reference to their performance assessment and to the expected impact of their practical usage in real traffic systems. In order to make the book accessible to readers of different backgrounds, some fundamental aspects of traffic theory as well as some basic control concepts, useful for better understanding the addressed topics, are provided in the book. This monograph can be used as a textbook for courses on transport engineering, traffic management and control. It is also addressed to experts working in traffic monitoring and control areas and to researchers, technicians and practitioners of both transportation and control engineering. The authors’ systematic vision of traffic modelling and control methods developed over decades makes the book a valuable survey resource for freeway traffic managers, freeway stakeholders and transportation public authorities with professional interests in freeway traffic systems. Advances in Industrial Control reports and encourages the transfer of technology in control engineering. The rapid development of control technology has an impact on all areas of the control discipline. The series offers an opportunity for researchers to present an extended exposition of new work in all aspects of industrial control.

Download or read book Modeling Estimation and Control of Distributed Parameter Systems written by Sebastien Blandin and published by . This book was released on 2012 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: The research presented in this dissertation is motivated by the need for well-posed mathematical models of traffic flow for data assimilation of measurements from heterogeneous sensors and flow control on the road network. A new 2 X 2 partial differential equation (PDE) model of traffic with phase transitions is proposed. The system of PDEs constitutes an extension to the Lighthill-Whitham-Richards model accounting for variability around the empirical fundamental diagram in the congestion phase. A Riemann solver is constructed and a variation on the classical Godunov scheme, required due to the non-convexity of the state-space, is implemented. The model is validated against experimental vehicle trajectories recorded at high resolution, and shown to capture complex traffic phenomena such as forward-moving discontinuities in the congestion phase, which is not possible with scalar hyperbolic models of traffic flow. A corresponding mesoscopic interpretation of these phenomena in terms of drivers behavior is proposed. The structure of the uncertainty distribution resulting from the propagation of initial uncertainty in weak entropy solutions to first order scalar hyperbolic conservation laws is characterized in the case of a Riemann problem. It is shown that at shock waves, the uncertainty is a mixture of the uncertainty on the left and right initial condition, and the consequences of this specific class of uncertainty on estimation accuracy is assessed in the case of the extended Kalman filter and the ensemble Kalman filter. This sets the basis for filtering-based traffic estimation and traffic forecast with appropriate treatment of the specific type of uncertainty arising due to the mathematical structure of the model used, which is of critical importance for road networks with sparse measurements. As a first step towards controlling general distributed models of traffic, a benchmark problem is investigated, in the form of a first order scalar hyperbolic conservation law. The weak entropy solution to the conservation law is stabilized around a uniform solution using boundary actuation. The control is designed to be compatible with the proper weak boundary conditions, which given specific assumptions guarantees that the corresponding initial-boundary value problem is well-posed. A semi-analytic boundary control is proposed and shown to stabilize the solution to the scalar conservation law. The benefits of introducing discontinuities in the solution are discussed. For traffic applications, this method allows us to pose the problem of ramp metering on freeways for congestion control and reduction of the amplitude of the capacity drop, as well as the problem of vehicular guidance for phantom jam stabilization on road networks, in a proper mathematical framework.

Download or read book Applications of Automatic Control Concepts to Traffic Flow Modeling and Control written by Markos Papageorgiou and published by Springer. This book was released on 1983 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Internet Teletraffic Modeling and Estimation written by Alexandre Barbosa de Lima and published by River Publishers. This book was released on 2013-01-31 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt: Network traffic has fractal properties such as impulsiveness, self-similarity, and long-range dependence over several time scales from milliseconds to minutes. These features have motivated the development of new traffic models and traffic control algorithms. Internet Teletraffic Modeling and Estimation presents a new statespace model for Internet traffic, which is based on a finite-dimensional representation of the Autoregressive Fractionally Integrated Moving Average (ARFIMA) random process. This book also investigates the modeling via Autoregressive (AR) processes.

Download or read book Stochastic Models Estimation and Control written by Peter S. Maybeck and published by Academic Press. This book was released on 1982-08-25 with total page 311 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume builds upon the foundations set in Volumes 1 and 2. Chapter 13 introduces the basic concepts of stochastic control and dynamic programming as the fundamental means of synthesizing optimal stochastic control laws.

Download or read book Data Driven Methods for Improved Estimation and Control of an Urban Arterial Traffic Network written by Leah Adrian Anderson and published by . This book was released on 2015 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transportation is a field which is universal in our society: people from every country, culture or background are familiar with the challenges of getting around in our built environment. Yet what is not always so obvious to the average traveler is how the techniques and tools of designing, observing, and controlling our modern transportation networks are derived. In fact, the theory of traffic engineering has many gaps and unknowns that are the topic of ongoing research efforts in the academic community. This work presents a collection of theoretical and practical methodologies to advance the study of traffic flow modeling, state estimation, and control of signalized roadways in particular. It uses theory from traditional transportation engineering, but also demonstrates the application of new tools from control theory and computer science to the specific application of signalized traffic networks. First, two numerical modeling dynamics representing traffic flows on signalized arterials are presented: the well-known Cell Transmission Model, a discretization of the physical hydrodynamic laws believed to govern vehicle flows, and a new Vertical Cell Model which resembles classical "store-and-forward" models with the addition of transit delays and finite buffer capacities. Each of these models is implemented in a common software framework, which provides an ideal experimental platform for direct comparison of the competing dynamics. A chapter in this dissertation contributes a validation and comparison of the two models against real vehicle trajectory data on an existing signalized road network. Accuracy and confidence in such traffic models requires complimentary methods of observing true traffic conditions to provide initial conditions and real-time state estimates. Yet there are many technological deficiencies in existing urban roadway detection systems that prevent the acquisition of a real-time estimate of arterial link state (or queue length) at signalized intersections. Hence this thesis also contains methodology to improve the estimates obtained from existing hardware by combining data from typical infrastructure sensors with new sources of Lagrangian probe measurements. These are then assimilated into a detailed model of flow dynamics. This technique was previously proposed for continuous-flow (freeway) networks, but required novel adaptions to be applied to an interrupted-flow setting. This dissertation next explores advancements in theoretically optimal control algorithms for statistically-modeled signalized queueing networks. In the context of a large body of previous work on flow-impeding control for vertical queueing networks, the practical challenges of traffic signal control are highlighted. Some of these challenges are tackled in the specific case of the max pressure controller, an algorithm derived from the field of communications networks that has been shown to optimize through-flow in an idealized network model. The lack of adequate measurements or demand-volume data has historically been a major limitation in advancing research on signalized arterial road networks. Yet the current revolution of inexpensive storage and processing of "big data" shows promise for improving daily operations of existing roadways without the need for expensive new hardware systems. One example of this potential appears is the case of traffic signal control. Existing traffic signals are capable of operating more efficiently by changing signal plans based on real-time demand measurements through a traffic responsive plan selection (TRPS) mode of operation (rather than depending on a rigid schedule for plan changes). However, this mode is rarely used in practice because its calibration process is not accessible or intuitive to traffic technicians. This dissertation presents an application of statistical learning techniques to improve the process of calibrating and implementing an existing TRPS mechanism. A proof-of-concept implementation using historical sensor data from a busy urban intersection demonstrates that real operational improvements may be immediately achievable using existing sensing infrastructure.

Download or read book Robust State Estimation and Control of Highway Traffic Systems written by Rashid Rahmati Kohan and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis, a modified second-order continuum model is used to describe the traffic behaviour along highways. The model is identified and verified using several sets of traffic measurements collected from a major highway in metropolitan Toronto, Canada. A robust nonlinear sliding mode observer is developed to generate estimates of average velocity and density for a segment of a highway within a corridor, given loop detector measurements at the end-points of the segment. The sliding mode approach has several advantages over other estimation techniques such as the Kalman Filtering including proof of estimate convergence and simplified computations. However, the primary advantage is the robustness of the observer with respect to unmodelled dynamics and disturbances. Unmodelled dynamics are associated with the traffic factors whose effects cannot be captured (properly) in the traffic flow models, e.g., road geometry and weather conditions. On the other hand, model disturbances such as unavailable (not measured) traffic flow at a ramp or measurements provided by a faulty detector can also create unpredictable traffic states. Based on the presented traffic model, a systematic design procedure is developed to make the observer robust with respect to the modelling uncertainties and unavailable traffic states. Simulation and experimental results show the effectiveness of the proposed observer in estimating the states of a highway traffic system. Moreover, a new decentralized state feedback linearizing controller for ramp metering using variable structure control is presented. The main aim is to develop a robust controller to locally stabilize freeway traffic despite the presence of disturbances and modelling errors. Simulation results show that the proposed controller provides improved performance in achieving the design objectives over other existing ramp control strategies such as neural network and linear feedback controllers.

Download or read book Fundamentals of Traffic Simulation written by Jaume Barceló and published by Springer Science & Business Media. This book was released on 2011-01-06 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt: The increasing power of computer technologies, the evolution of software en- neering and the advent of the intelligent transport systems has prompted traf c simulation to become one of the most used approaches for traf c analysis in s- port of the design and evaluation of traf c systems. The ability of traf c simulation to emulate the time variability of traf c phenomena makes it a unique tool for capturing the complexity of traf c systems. In recent years, traf c simulation – and namely microscopic traf c simulation – has moved from the academic to the professional world. A wide variety of traf- c simulation software is currently available on the market and it is utilized by thousands of users, consultants, researchers and public agencies. Microscopic traf c simulation based on the emulation of traf c ows from the dynamics of individual vehicles is becoming one the most attractive approaches. However, traf c simulation still lacks a uni ed treatment. Dozens of papers on theory and applications are published in scienti c journals every year. A search of simulation-related papers and workshops through the proceedings of the last annual TRB meetings would support this assertion, as would a review of the minutes from speci cally dedicated meetings such as the International Symposiums on Traf c Simulation (Yokohama, 2002; Lausanne, 2006; Brisbane, 2008) or the International Workshops on Traf c Modeling and Simulation (Tucson, 2001; Barcelona, 2003; Sedona, 2005; Graz 2008). Yet, the only comprehensive treatment of the subject to be found so far is in the user’s manuals of various software products.

Download or read book Nonlinear Control Under Nonconstant Delays written by Nikolaos Bekiaris-Liberis and published by SIAM. This book was released on 2013-09-25 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors have developed a methodology for control of nonlinear systems in the presence of long delays, with large and rapid variation in the actuation or sensing path, or in the presence of long delays affecting the internal state of a system. In addition to control synthesis, they introduce tools to quantify the performance and the robustness properties of the designs provided in the book. The book is based on the concept of predictor feedback and infinite-dimensional backstepping transformation for linear systems and the authors guide the reader from the basic ideas of the concept?with constant delays only on the input?all the way through to nonlinear systems with state-dependent delays on the input as well as on system states. Readers will find the book useful because the authors provide elegant and systematic treatments of long-standing problems in delay systems, such as systems with state-dependent delays that arise in many applications. In addition, the authors give all control designs by explicit formulae, making the book especially useful for engineers who have faced delay-related challenges and are concerned with actual implementations and they accompany all control designs with Lyapunov-based analysis for establishing stability and performance guarantees.

Download or read book Modeling Computation and Control of Vehicular Traffic Flow Using Variational Theory written by Jia Li and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Congestion has been a longstanding problem in urban transportation systems. It is the root of system deterioration in mobility, safety and sustainability, manifested as travel delay and travel uncertainty, crashes, air pollution, etc. A strong science into the understanding, modeling, computation and control of congestion dynamics in complex, uncertain and intelligent traffic systems is thus at the core of incorporating emerging technologies and devising sound and effective traffic management strategies.This dissertation aims at addressing the shortcomings of classical macroscopic traffic flow models in dealing with the boundary measurements and control. Due to construction, the traditional hydrodynamics based traffic modeling approaches are usually incapable or extremely tedious in incorporating trajectory-level details in either modeling or control. This constitutes the main hurdle for integrating sound physics with empirical observations in traffic systems estimation and control, especially when mobile or other non-regular sensing techniques are involved.In this dissertation, I develop a novel variational theory based traffic flow modeling framework and provide detailed discussions on its implications for traffic systems estimation, computation and control problems. The new modeling approach explores and consolidates the linkage between hyperbolic conservation equations associated with the kinematic wave theory and Hamilton-Jacobi equations associated with the optimal control theory. In a broader context, this linkage represents the translation between PDE (partial differential equation) and ODE (ordinary differential equation) problems. Though mathematically equivalent, the latter perspective allows us to tackle the moving observations more easily because of relaxed assumptions on boundary geometry. In addition, the analytical and numerical difficulties associated with solving traffic flow models are suppressed, thanks to the variational principle pertaining to the latter formulation. Major results presented in this dissertation include the following. First, I derive the variational formulations for multi-class and non-equilibrium traffic flow models respectively, through exploiting the isomorphic relation between a conservation law problem with its auxiliary optimal control problem. In the derivations, the relation of kinematic wave and solution to the optimal control problem are analyzed in detail. Based on the new formulations, simplified solution schemes are proposed. These solution schemes are flexible with the setting of computational grids and boundary conditions. Analysis of their error bounds are given. Then I look into the calibration of Hamiltonian, i.e. fundamental diagram, in multi-lane freeway setting. An automated adaptive calibrator is constructed using the mixed integer programming (MIP) technique and tested using I-80 freeway data. At last, I presented a decentralized urban signalized traffic network control scheme, motivated by the queuing properties implied in the variational principle.