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161
SelfControl of Traffic Lights and Vehicle Flows in Urban Road Networks
, 2008
"... Based on fluiddynamic and manyparticle (carfollowing) simulations of traffic flows in (urban) networks, we study the problem of coordinating incompatible traffic flows at intersections. Inspired by the observation of selforganized oscillations of pedestrian flows at bottlenecks [D. Helbing and P ..."
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Cited by 40 (10 self)
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Based on fluiddynamic and manyparticle (carfollowing) simulations of traffic flows in (urban) networks, we study the problem of coordinating incompatible traffic flows at intersections. Inspired by the observation of selforganized oscillations of pedestrian flows at bottlenecks [D. Helbing and P. Molnár, Phys. Rev. E 51 (1995) 4282–4286], we propose a selforganization approach to traffic light control. The problem can be treated as multiagent problem with interactions between vehicles and traffic lights. Specifically, our approach assumes a prioritybased control of traffic lights by the vehicle flows themselves, taking into account shortsighted anticipation of vehicle flows and platoons. The considered local interactions lead to emergent coordination patterns such as “green waves ” and achieve an efficient, decentralized traffic light control. While the proposed selfcontrol adapts flexibly to local flow conditions and often leads to noncyclical switching patterns with changing service sequences of different traffic flows, an almost periodic service may evolve under certain conditions and suggests the existence of a spontaneous synchronization of traffic lights despite the varying delays due to variable vehicle queues and travel times. The selforganized traffic light control is based on an optimization and a stabilization rule, each of which performs poorly at high utilizations of the road network, while their proper combination reaches a superior performance. The result is a considerable reduction not only in the average travel times, but also of their variation. Similar control approaches could be applied to the coordination of logistic and production processes.
Rethinking information theory for mobile ad hoc networks
 IEEE Communications Magazine, Submitted
, 2007
"... The subject of this paper is the longstanding open problem of developing a general capacity theory for wireless networks, particularly a theory capable of describing the fundamental performance limits of mobile ad hoc networks (MANETs). A MANET is a peertopeer network with no preexisting infrast ..."
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Cited by 37 (6 self)
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The subject of this paper is the longstanding open problem of developing a general capacity theory for wireless networks, particularly a theory capable of describing the fundamental performance limits of mobile ad hoc networks (MANETs). A MANET is a peertopeer network with no preexisting infrastructure. MANETs are the most general wireless networks, with singlehop, relay, interference, mesh, and star networks comprising special cases. The lack of a MANET capacity theory has stunted the development and commercialization of many types of wireless networks, including emergency, military, sensor, and community mesh networks. Information theory, which has been vital for links and centralized networks, has not been successfully applied to decentralized wireless networks. Even if this was accomplished, for such a theory to truly characterize the limits of deployed MANETs it must overcome three key roadblocks. First, most current capacity results rely on the allowance of unbounded delay and reliability. Second, spatial and timescale decompositions have not yet been developed for optimally modeling the spatial and temporal dynamics of wireless networks. Third, a useful network capacity theory must integrate rather than ignore the important role of overhead messaging and feedback. This paper describes some of the shifts in thinking that may be needed to overcome these roadblocks and
A General Methodology for Mathematical Analysis of MultiAgent Systems
 USC Information Sciences
, 2001
"... We propose a general mathematical methodology for studying the dynamics of multiagent systems in which complex collective behavior arises out of local interactions between many simple agents. The mathematical model is composed of a system of coupled differential equations describing the macroscop ..."
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Cited by 34 (4 self)
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We propose a general mathematical methodology for studying the dynamics of multiagent systems in which complex collective behavior arises out of local interactions between many simple agents. The mathematical model is composed of a system of coupled differential equations describing the macroscopic, or collective, dynamics of an agentbased system. We illustrate our approach by applying it to analyze several agentbased systems, including coalition formation in an electronic marketplace, and foraging and collaboration in a group of robots. 1.
Empirical features of congested traffic states and their implications for traffic modeling
 TRANSPORTATION SCIENCE
, 2004
"... We investigate characteristic properties of the congested traffic states on a 30 km long stretch of the German freeway A5 north of Frankfurt/Main. Among the approximately 245 breakdowns of traffic flow in 165 days, we have identified five different kinds of spatiotemporal congestion patterns and th ..."
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Cited by 34 (9 self)
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We investigate characteristic properties of the congested traffic states on a 30 km long stretch of the German freeway A5 north of Frankfurt/Main. Among the approximately 245 breakdowns of traffic flow in 165 days, we have identified five different kinds of spatiotemporal congestion patterns and their combinations. Based on an “adaptive smoothing method” for the visualization of detector data, we also discuss particular features of breakdowns such as the “boomerang effect ” which is a sign of linearly unstable traffic flow. Controversial issues such as “synchronized flow” or stopandgo waves are addressed as well. Finally, our empirical results are compared with different theoretical concepts and interpretations of congestion patterns, in particular first and secondorder macroscopic traffic models.
Kicked Burgers turbulence
 J. Fluid Mech
"... J. Fluid Mech.; in press Burgers turbulence subject to a force f(x,t) = ∑ j fj(x)δ(t − tj), where the tj’s are “kicking times ” and the “impulses ” fj(x) have arbitrary space dependence, combines features of the purely decaying and the continuously forced cases. With largescale forcing this “kicke ..."
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Cited by 26 (6 self)
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J. Fluid Mech.; in press Burgers turbulence subject to a force f(x,t) = ∑ j fj(x)δ(t − tj), where the tj’s are “kicking times ” and the “impulses ” fj(x) have arbitrary space dependence, combines features of the purely decaying and the continuously forced cases. With largescale forcing this “kicked ” Burgers turbulence presents many of the regimes proposed by E, Khanin, Mazel and Sinai (1997) for the case of random whiteintime forcing. It is also amenable to efficient numerical simulations in the inviscid limit, using a modification of the Fast Legendre Transform method developed for decaying Burgers turbulence by Noullez and Vergassola (1994). For the kicked case, concepts such as “minimizers ” and “main shock”, which play crucial roles in recent developments for forced Burgers turbulence, become elementary since everything can be constructed from simple twodimensional areapreserving Euler– Lagrange maps.
Toward benchmarking of microscopic traffic flow models. Transportation Research Record
 Journal of the Transportation Research Board
"... Abstract: For the simulation of traffic flows various macroscopic and microscopic models exist. Developing these models it is important to check the models against reality, whereas there are wellestablished means how to do this for macroscopic fluiddynamical models. For microscopic models this wor ..."
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Cited by 26 (4 self)
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Abstract: For the simulation of traffic flows various macroscopic and microscopic models exist. Developing these models it is important to check the models against reality, whereas there are wellestablished means how to do this for macroscopic fluiddynamical models. For microscopic models this work has yet to be done. This article is intended as a first step towards a common benchmarking of those models. A method is suggested to test microscopic models against singlecar data sets and applied to two public available singlecar data sets recorded by C. Daganzo on a one lane road in the USA in 1997. The calibration of the used models is done by analysing the deviations of the travel times on the observed street segments. As a result one gets a single number for each model giving the mean percentage error it produces in comparison to reality. This way the models can be compared directly to each other quantitatively. Furthermore, the obtained results point towards some deficiencies of the models and give ideas how to correct them. Key Words: modeling, simulation, traffic flow, benchmark.
A pedestrian’s view on interacting particle systems, KPZ universality, and random matrices
, 2010
"... ..."
The ergodic theory of traffic jams
 Journal of Statistical Physics
, 2001
"... We introduce and analyze a simple probabilistic cellular automaton which emulates the flow of cars along a highway. Our Traffic CA captures the essential features of several more complicated algorithms, studied numerically by ..."
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Cited by 20 (0 self)
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We introduce and analyze a simple probabilistic cellular automaton which emulates the flow of cars along a highway. Our Traffic CA captures the essential features of several more complicated algorithms, studied numerically by
Selforganized patterns and traffic flow in colonies of organisms: from bacteria and social insects to vertebrates
, 2008
"... ..."
Ergodic Properties of a Simple Deterministic Traffic Flow Model Re(al)visited
 J. Stat. Phys
, 2002
"... We study statistical properties of a family of maps acting in the space of integer valued sequences, which model dynamics of simple deterministic traffic flows. We obtain asymptotic (as time goes to infinity) properties of trajectories of those maps corresponding to arbitrary initial configurations ..."
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Cited by 17 (6 self)
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We study statistical properties of a family of maps acting in the space of integer valued sequences, which model dynamics of simple deterministic traffic flows. We obtain asymptotic (as time goes to infinity) properties of trajectories of those maps corresponding to arbitrary initial configurations in terms of statistics of densities of various patterns and describe weak attractors of these systems and the rate of convergence to them. Previously only the so called regular initial configurations (having a density with only finite fluctuations of partial sums around it) in the case of a slow particles model (with the maximal velocity 1) have been studied rigorously. Applying ideas borrowed from substitution dynamics we are able to reduce the analysis of the traffic flow models corresponding to the multilane traffic and to the flow with fast particles (with velocities greater than 1) to the simplest case of the flow with the onelane traffic and slow particles, where the crucial technical step is the derivation of the exact lifetime for a given cluster of particles. Applications to the optimal redirection of the multilane traffic flow are discussed as well.