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In this paper, we present a decentralized control framework for the coordination of connected vehicles and traffic lights in urban intersections. The framework uses gradient-based methods to dynamically coordinate, at every time-step, the planned intersection arrival times of vehicles and the planned switching times of traffic lights. Assuming no constraints, vehicles then use analytical optimal control methods to determine a nominal acceleration profile intended to place them at the intersection at the desired arrival time. Finally, using control barrier functions, the agents' accelerations and arrival times are modified to ensure safety and feasibility. The work in this paper builds on existing research on safe-set nonlinear control methods, multi-agent gradient-based methods, and optimal control methods used to tackle the intelligent intersection management problem. Here, we integrate the use of these different approaches to present a comprehensive control architecture that can flexibly coordinate the timing of both vehicles and traffic lights, while maintaining safety and feasibility. Simulations show that the method can save between 4% and 15% in fuel consumption and between 55% and 70% in delay for different traffic conditions. [ABSTRACT FROM AUTHOR]

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Background: Most countries have detailed lists of traffic rules and elaborate legal regimes for penalizing drivers who break them. Previous research has suggested that drivers tend to drive more safely after receiving penalties for traffic infringements.Methods: We linked driver-level data on infringements and crashes in Queensland, Australia (1995-2010) with information on the licence histories of all drivers in the state. We used a case-crossover design to examine drivers' risk of crashing in the month following an infringement penalty. We also examined whether changes in crash risk following infringement penalties varied according to driver age and gender, type of infringement and whether the offender was at fault in a subsequent crash.Results: Drivers had higher risks of crashes following infringement penalties [odds ratio (OR) 1.32; 95% confidence interval (CI) 1.29-1.36], especially crashes in which the offender was at fault (1.41; 1.36-1.46). Crash risk relative to a comparable period was particularly high for teenage drivers (1.55; 1.34-1.78) and among drivers penalized for dangerous driving (3.19; 2.52-4.03) or driving under the influence of alcohol (1.99; 1.67-2.37). The risk remained relatively high for more than 6 months after the penalty, but declined steadily over this period.Conclusions: Crash risk among drivers in Queensland was higher, not lower, following receipt of penalties for traffic infringements. Penalties themselves are unlikely to increase crash risk. A more likely explanation is that penalties (or the corresponding infringements) mark episodes of risky driving. Our findings suggest that such episodes trounce any deterrent effect penalties may produce. [ABSTRACT FROM AUTHOR]

In this paper, an iterative learning approach for the freeway density control under ramp metering and speed regulation is developed in a macroscopic level traffic environment. Rigorous analyses show that the proposed learning control schemes guarantee the asymptotic convergence of the traffic density to the desired one. The two major features of the learning-based density control are 1) less prior modeling knowledge required in the control system design and 2) the ability to reject exogenous traffic perturbations. The control schemes are applied to a freeway model, and simulation results confirm the efficacy of the proposed approach. [ABSTRACT FROM AUTHOR]

Man-made disasters usually lead to the tightening of safety regulations, because rule breaking is seen as a major cause of them. This reaction is based on the assumptions that the safety rules are good and that the rule-breakers are wrong. The reasons the personnel of a coke factory gave for breaking rules raise doubt about the tenability of these assumptions. It is unlikely that this result would have been achieved on the basis of a disaster evaluation, or high-reliability theory. In both approaches, knowledge of the consequences of human conduct hinders an unprejudiced judgement about where the blame for rule breaking lies. [ABSTRACT FROM AUTHOR]

In this paper the authors find the optimal allocation of servicing periods to a facility servicing N incoming traffic streams. In our model it is assumed that stream flows are deterministic, that there is a fixed amount of lime lost, τi , when the server switches attention from the ith to the i + 1st stream and that the objective is to minimize time average delay. [ABSTRACT FROM AUTHOR]

Reality proved that the persons who commit manslaughters, usually are not deprived of their freedom, this hindering the post-delictum general prevention as regards the other car drivers who breach the traffic rules, and this situation requires a legal involvement to limit to courts the possibilities of legal individualization in ways of letting out the persons who, being culpable and disregarding the compulsory traffic rules on public roads, provoke the death of their fellows. [ABSTRACT FROM AUTHOR]

Robust road-boundary extraction/tracking is one of the main problems in autonomous roadway navigation. Although the road boundary can be defined by various means including lane markings, curbs, and borders of vegetation, this paper focuses on road-boundary tracking using curbs. A vehicle-mounted (downward tilted) 2-D laser-measurement system is utilized to detect the curbs. The tracking problem is difficult because both the vehicle is moving and the target is disappearing, reappearing, and maneuvering in clutter. The interacting-multiple-model probabilistic-data-association filter (IMMPDAF) is proposed to solve the problems after detailed analysis. Track initiation, confirmation, and deletion are performed using the sequential-probability-ratio test. Extensive simulations followed by experiments in a campus environment show that the road-boundary tracking utilizing curbs is possible and robust through IMMPDAF. [ABSTRACT FROM AUTHOR]

The focuses of this paper are optimal traffic regulation after a major disaster and evaluation of capacity reliability of a network. The paper firstly discusses the context of traffic regulation and its importance after a major disaster. Then, this problem is formulated as an optimisation program in which the traffic regulator attempts to regulate the amount of traffic movements or access to some areas so as to maximise the traffic volumes in the network while (a) link flows must be less than link capacities and (b) re-routing effect due to changes of traffic condition in the network is allowed. The re-routing behaviour is assumed to follow Probit Stochastic User's Equilibrium (SUE). The paper explains an optimisation algorithm based on an implicit programming approach for solving this problem with the SUE condition. With this optimisation problem, the randomness of the link capacities (to represent random effects of the disaster) is introduced and the paper describes an approach to approximate the capacity reliability of the network using Monte-Carlo simulation. The paper then adopts this approach to evaluate the performances of different traffic regulation policies with a small network and a test network of Kobe city in Japan. [ABSTRACT FROM AUTHOR]

Road traffic is a typical example of an occupation with bilateral care and activity choices. In such a setting, common liability rules which simply divide damages cannot induce efficient outcomes. It is shown that fines for the violation of traffic regulations which depend on the occurrence of an accident can induce optimal behaviour. The properties of such efficient fines are derived. In particular, efficient fines tend to increase more than proportionally with the severity of an offence, while fines for repeat offenders can rise at a decreasing rate with the number of violations. To evaluate the scope for efficiency-enhancing reforms of fine systems, it is investigated whether actual regulations particularly for speeding conform to the non-proportionality requirement in selected European countries. [ABSTRACT FROM AUTHOR]