An Introduction To Traffic Flow Theory

The understanding of empirical traf?c congestion occurring on unsignalized mul- lane highways and freeways is a key for effective traf?c management, control, or- nization, and other applications of transportation engineering. However, the traf?c ?ow theories and models that dominate up to now in transportation research journals and teaching programs of most universities cannot explain either traf?c breakdown or most features of the resulting congested patterns. These theories are also the - sis of most dynamic traf?c assignment models and freeway traf?c control methods, which therefore are not consistent with features of real traf?c. For this reason, the author introduced an alternative traf?c ?ow theory called three-phase traf?c theory, which can predict and explain the empirical spatiot- poral features of traf?c breakdown and the resulting traf?c congestion. A previous book “The Physics of Traf?c” (Springer, Berlin, 2004) presented a discussion of the empirical spatiotemporal features of congested traf?c patterns and of three-phase traf?c theory as well as their engineering applications. Rather than a comprehensive analysis of empirical and theoretical results in the ?eld, the present book includes no more empirical and theoretical results than are necessary for the understanding of vehicular traf?c on unsignalized multi-lane roads. The main objectives of the book are to present an “elementary” traf?c ?ow theory and control methods as well as to show links between three-phase traf?c t- ory and earlier traf?c ?ow theories. The need for such a book follows from many commentsofcolleaguesmadeafterpublicationofthebook“ThePhysicsofTraf?c”.

This book describes a coherent approach to the explanation of the movement of individual vehicles or groups of vehicles. To avoid possible misunderstandings, some preliminary remarks are called for. 1. This is intended to be a textbook. It brings together methods and approaches that are widely distributed throughout the literature and that are therefore difficult to assess. Text citations of sources have been avoided; literature references are listed together at the end of the book. 2. The book is intended primarily for students of engineering. It describes the theoretical background necessary for an understanding of the methods by which links in a road network are designed and dimensioned or by which traffic is controlled; the methods themselves are not dealt with. It may also assist those actually working in such sectors to interpret the results of traffic flow measure ments more accurately than has hitherto been the case. 3. The book deals with traffic flow on links between nodes, and not at nodes themselves. Many readers will probably regret this, since nodes are usually the bottlenecks which limit the capacity of the road network. A book dedicated to the node would be the obvious follow-up. A separation of link and node is justified, however, partly because the quantity of material has to be kept within reasonable bounds and partly because the treatment of traffic flow at nodes requires additional mathematical techniques (in particular, those relating to queueing theory).

Recent contributions to traffic flow theory are presented in a related manner and with a consistent set of notations.

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.

The core of ths book presents a theory developed by the author to combine the recent insight into empirical data with mathematical models in freeway traffic research based on dynamical non-linear processes.

Creating Traffic Models is a challenging task because some of their interactions and system components are difficult to adequately express in a mathematical form. Traffic Flow Theory: Characteristics, Experimental Methods, and Numerical Techniques provide traffic engineers with the necessary methods and techniques for mathematically representing traffic flow. The book begins with a rigorous but easy to understand exposition of traffic flow characteristics including Intelligent Transportation Systems (ITS) and traffic sensing technologies. Includes worked out examples and cases to illustrate concepts, models, and theories Provides modeling and analytical procedures for supporting different aspects of traffic analyses for supporting different flow models Carefully explains the dynamics of traffic flow over time and space

Transportation is generally concerned with the efficient, safe, and sustainable movement of people and goods. Transportation engineers work on various aspects of the five stages essential in the life cycle of a transportation facility: planning, designing, building, operating, and maintaining. In the planning stage, we typically forecast traffic demands for a future year/analysis period, perform a preliminary evaluation of alternative solutions, or identify priorities for system improvements. This text provides a comprehensive and concise treatment of the topic of traffic flow theory and includes several topics relevant to today's highway transportation system. It provides the fundamental principles of traffic flow theory as well as applications of those principles for evaluating specific types of facilities (freeways, intersections, etc.). Newer concepts of Intelligent transportation systems (ITS) and their potential impact on traffic flow are discussed. State-of-the-art in traffic flow research and microscopic traffic analysis and traffic simulation have significantly advanced and are also discussed in this text. This textbook is meant for use in advanced undergraduate/graduate level courses in traffic flow theory with prerequisites including two semesters of calculus, statistics, and an introductory course in transportation. The text would also be of interest to transportation professionals as a refresher in traffic flow theory, or as a reference.