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Different emerging threats highlighted the relevance of recovery and adaptation modelling in the functioning of societal systems. However, as modelling of systems becomes more complex, its effort increases challenging the practicality of the engineering analyses required for efficient recovery and adaptation. In the present work, metamodels are researched as a tool to enable these analyses in traffic networks. One of the main advantages of metamodeling is their synergy with the short decision times required in recovery and adaptation. A sequential global metamodeling technique is proposed and applied to three macroscopic day-to-day user-equilibrium models. Two reference contexts of application are researched: optimal recovery to a perturbation (with response times reduced by 98% with loss of accuracy lower than 1%) and adaptation under uncertainty with perturbation-dependent optimality. Results show that metamodeling-based metaheuristics enable fast resource-intensive engineering analyses of traffic recovery and adaptation, which may change the paradigm of decision-making in this field [ABSTRACT FROM AUTHOR]

The Hyperloop concept, pod speed competitions and current project developments have recently attracted much publicity. In this paper the transport technology of the vacuumed tube transport project Hyperloop is assessed through a system analysis of its principal aims, functional design, transport capacity and demand in comparison with existing commercial airlines, high-speed rail, and Maglev lines. First, the potential for high-speed long-distance travel demand for Hyperloop based on existing airline transport volumes between major airports in Germany on the one hand, and the proposed Hyperloop link from Los Angeles to San Francisco in California on the other, is assessed in general terms. Second, the technical feasibility of the proposed Hyperloop concept for vehicle design, capacity, operations, propulsion, guidance, energy supply, traffic control, safety, alignment, and construction is discussed in more detail. Third, possible environmental impacts and uncertain investment, operating and maintenance costs for implementation of a Hyperloop line are described. Finally, the risks for further Hyperloop project development and the need for more transparent research are emphasized. [ABSTRACT FROM AUTHOR]

The development of modern IT techniques and technologies creates appropriate possibilities for automation of navigation and construction of decision support systems in ship control. The solutions proposed by these systems should ensure the safe performance of maneuvers, take into account applicable traffic regulations and should be rational, i.e. apply criteria used and accepted by people. The basis for implementing these types of systems is the analysis of decision-making processes in ship control carried out by navigators. The development of the decision process model is the basis for the design and construction of navigator decision support systems. The article presents a comprehensive analysis of issues related to modelling of decision-making situations and implementation of decision-making processes in ship control in a restricted (inland) area. The paper presents methods and algorithms for decision support in a collision situation, defining a safe trajectory, taking into account elements of the ship's own dynamic properties, road law provisions, navigation restrictions and changes in the strategy of behavior in relation to various objects encountered. The purpose of this article is the concept of a model of decision support system within a specific geospatial situation in three dimensions for complex calculations regarding the movement of inland vessels. [ABSTRACT FROM AUTHOR]

Road safety has become a major public issue in China. This study collected a total of 396 road traffic accident cases that occurred in 28 provinces from 1985 to 2014 in China. The type of vehicles involved in the accidents includes cargo vehicles (126), passenger vehicles (253), dangerous chemicals transport vehicles (128), and cars (9). A new systems approach that integrates the causal categories framework based on the human factor analysis and classification system (HFACS) and the contributory factor interactions model (CFIM) was applied to conduct analysis of road traffic accidents to determine whether systems approaches should be used during road accident analysis efforts. The analysis of results leads to the following conclusions. (i) According to the causal categories framework based on HFACS, the frequency of “unsafe behaviours” is highest at the category level; the frequency of “violations” is the highest at the subcategory level. “Overloading/overcrowding,” “speeding,” “failed to provide supervision,” and “fatigue driving” should receive attention at the special indicator level. (ii) The new systems-based method that integrated the HFACS and the CFIM, which highlights the interactions between all levels of the causal categories, is a suitable method to analyse road traffic accidents. (iii) All latent categories, including “outside factors,” “organizational influences,” “unsafe supervision,” and “preconditions for unsafe behaviours,” can affect “unsafe behaviours”; “outside factors,” “organizational influences,” “unsafe supervision,” and “preconditions for unsafe behaviours” can influence each other. These interactions have not been quantitatively examined in previous studies. The findings of this study also demonstrate that the OR is a suitable technique to quantitatively examine the interactions among contributory factors. [ABSTRACT FROM AUTHOR]

Road traffic control rooms rely on human operators to monitor and interact with information presented on multiple displays. Past studies have found inconsistent use of available visual information sources in such settings across different domains. In this study, we aimed to broaden the understanding of observer behaviour in control rooms by analysing a case study in road traffic control. We conducted a field study in a live road traffic control room where five operators responded to incidents while wearing a mobile eye tracker. Using qualitative and quantitative approaches, we investigated the operators' workflow using ergonomics methods and quantified visual information sampling. We found that individuals showed differing preferences for viewing modalities and weighting of task components, with a strong coupling between eye and head movement. For the quantitative analysis of the eye tracking data, we propose a number of metrics which may prove useful to compare visual sampling behaviour across domains in future. [ABSTRACT FROM AUTHOR]

In light of previous work [Phys. Rev. E60 4000 (1999)], a modified coupled-map car-following model is proposed by considering the headways of two successive vehicles in front of a considered vehicle described by the optimal velocity function. The non-jam conditions are given on the basis of control theory. Through simulation, we find that our model can exhibit a better effect as p = 0.65, which is a parameter in the optimal velocity function. The control scheme, which was proposed by Zhao and Gao, is introduced into the modified model and the feedback gain range is determined. In addition, a modified control method is applied to a mixed traffic system that consists of two types of vehicle. The range of gains is also obtained by theoretical analysis. Comparisons between our method and that of Zhao and Gao are carried out, and the corresponding numerical simulation results demonstrate that the temporal behavior of traffic flow obtained using our method is better than that proposed by Zhao and Gao in mixed traffic systems. [ABSTRACT FROM AUTHOR]

The system of sea waterways, as defined in this article, consists of three subsystems: waterways, navigational, and traffic control. This author has defined a state vector for conditions of safe operation of ships on a waterway and described interrelations between parameters of sea waterway system and the state vector of safe ship operation conditions. [ABSTRACT FROM AUTHOR]

Railway signaling has become more important over the years, with the increase in railway traffic and the use of highspeed trains. Since the most important aspect of a railway signaling system is safety, the decision-making ?interlocking system? is the critical element of a railway-signaling system. To satisfy the safety standards set for railway-signaling systems, the interlocking software design must be taken into account, using formal methods. In this study, an automata-based railway signaling and interlocking system is introduced and implemented, using a fail-safe programmable logic controller (PLC) on a scale railway model. [ABSTRACT FROM AUTHOR]

Speed Optimization in an Unplanned Traffic (SOUT) is a very promising research problem. Searching for an efficient optimization algorithm to increase the degree of speed optimization and thereby increasing the traffic flow in an unplanned zone is a widely concerning issue. However, very few research works have been carried out on the optimization of the lane usage and speed optimization simultaneously. This paper presents a novel SOUT technique to solve the problem optimally using the knowledge derived by analyzing the speed of vehicles, which, in turn will act as a guide in designing lanes optimally to provide better optimized traffic. Also, base model estimates for different features like dimensional factors for the geometric design as well as different traffic control features are being adjusted by the accident factors. Knowledgebased analysis technique is applied to the proposed design and speed optimization plan. The experimental results and observations are quite encouraging. [ABSTRACT FROM AUTHOR]

Abstract: In the present paper, a new CA-based model considering the following car horning is established and is analyzed in great detail. Firstly, how the following car horning can influence the traffic system is discussed. Secondly, by applying the cross-covariance method, proper parameters are indicated to explore the phase transition features of the model. The results show that the model proposed in this paper can simulate complex and realistic traffic phenomena. [Copyright &y& Elsevier]

This paper presents a platform used to acquire, analyse and transmit data from a vehicle to a Control Centre as part of a Pay-As-You-Drive system. The aim is to monitor vehicle usage (how much, when, where and how) and, based on this information, assess the associated risk and set an appropriate insurance premium. To determine vehicle usage, the system analyses the driver's respect for speed limits, driving style (aggressive or non-aggressive), mobile telephone use and the number of vehicle passengers. An electronic system on board the vehicle acquires these data, processes them and transmits them by mobile telephone (GPRS/UMTS) to a Control Centre, at which the insurance company assesses the risk associated with vehicles monitored by the system. The system provides insurance companies and their customers with an enhanced service and could potentially increase responsible driving habits and reduce the number of road accidents. [ABSTRACT FROM AUTHOR]

Bridges in the United Kingdom (UK) are subject to various physical processes that result in their deterioration over time. They can be constructed using different materials such as concrete or steel, or in combination with other materials, with varying number of spans and are used to carry different levels of loads. Inevitably, bridges deteriorate over time at different rates and they are vulnerable to varying forms of deterioration (e.g. rusting, corrosion). Timely maintenance activities that are well-planned and carried out with minimal disruption to road users can present substantial savings in terms of both time and money for both bridge owners and road users. As a result, the likelihood of disruptive emergency maintenance will be reduced and subsequent maintenance costs over the service life of bridges will not build up significantly due to neglect. To tackle the complicated issues regarding bridge management, research activities in the UK as well as other countries in continental Europe concentrate largely on the bridge management process, with attention given to improving the use of limited finances so as to maximize the returns from the maintenance and repair of the bridge stock as well as reduce additional costs due to traffic delays and lane closures for these activities. This project aims to first appreciate current bridge management systems (BMS), understand the practices used for determining bridge conditions and aid the decision-making process by using a systems approach. The study includes a critical review of other BMS's used worldwide, development of models to predict bridge condition over time, analysis of the various road user costs and using different optimizing techniques to best allocate finances and optimize bridge performance. [ABSTRACT FROM AUTHOR]

As they involve many interacting agents behaving in numerous ways that are extremely difficult to predict, urban transportation systems are complex in nature. The development of intermodal passenger transportation solutions to address the mobility issues constitutes a major thrust area of urban transport policies. But, to offer citizens comprehensive seamless mobility, intermodal transportation system management (ITSM) requires the integration of two major components. The traffic regulation support system, to help the operator responsible for the regulation tasks: coordination of timetables, synchronising arrival and departure times between the different transportation modes, and the traveller information system, giving customers access to information and using a comprehensive set of information tools. In this paper, a generic model of a transport management system, integrating these two components is proposed. This generic model is then used to elaborate a traffic regulation system in the case of a bimodal transportation system (tram-bus). The traffic regulation support system, based on the decision model of an operator, and the traveler information system are described. [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]

As transportation agencies seek to better manage and operate the transportation system, there is an increasing need for traffic condition data across the roadway network. Wireless location technology (WLT)-based traffic monitoring offers the opportunity to directly measure link travel times on a significantly larger portion of the roadway system than is currently monitored. In WLT-based monitoring, the locations of wireless devices (such as cellular phones) in vehicles are monitored. A series of these positions are then used to derive vehicle speeds on links, effectively making the wireless devices probes in the traffic stream. While this idea is conceptually appealing, previous field deployments have not been able to successfully implement this concept. This paper describes the results of a study that used simulation to examine the efficacy of WLT-based monitoring systems under various configurations. Two case studies were used to investigate how WLT system design and roadway network configuration impact the overall effectiveness of WLT-based monitoring systems. Conclusions on how these systems should be designed and where they are likely to function best are also included. The results of this paper show that while first-generation WLT-based monitoring systems can be used to monitor relatively simple networks, additional design refinements are needed before they can be used across a broad spectrum of roadway conditions. [ABSTRACT FROM AUTHOR]

Managing infrastructure data is a very complex task due to the heterogeneous nature of the several processes involved. In this article, a web information model based on extensible markup language (XML) is introduced to demonstrate the benefits that such a framework can bring to the road infrastructure data management scene. To build this model, a two-step strategy is identified and described in this article. This includes using novel computer modeling techniques based on the unified modeling language to build conceptual models of XML vocabulary for improved data description. A case study is provided to illustrate the concepts and strategies. This study delves into the application derived from current practices employed by transportation agencies to deal with their road infrastructure data at early stages of the life cycle management processes. The advantages, limitations, and future expectations of the new methodology are discussed. Based on this research, the proposed model can be adapted to different types of civil infrastructure assets, with great potential to improve data integration, accessibility, reusability, and interoperability of several infrastructure management processes. [ABSTRACT FROM AUTHOR]

This work deals with the analysis and design of reliable traffic control systems for urban transportation networks. The dynamics of queue length in front of the Intersections are captured by a nonlinear state space model where a limit-reset function is introduced to maintain the non-negativity of the queues for traffic conditions ranging from undersaturation to oversaturation. A reliable control system is then synthesized to maintain system integrity (stability and vehicle flow regulation) under partial system failure brought about by local faults such as sensor and actuator failure, vehicle accidents and severing of communication links. It is shown that the reliable conditions are rather mild and can readily be satisfied by a properly designed decentralized propotional integral-type controller. A detailed case study is also included in this work to demonstrate the properties of a reliable traffic network. [ABSTRACT FROM AUTHOR]

This paper presents an operation partitioning problem (OPP) that arises from the design of an automated assembly system. To reduce the traffic flow of the system, the OPP assigns operations to machines so that the total number of movements of jobs between machines is minimized. This problem has applications in flexible manufacturing and VLSI design. In flexible manufacturing, OPP relates to a part grouping problem in which different parts are grouped into families. In VLSI design, this problem is related to a VLSI design problem in which a large circuit is partitioned into layers of small circuits, in this paper, we develop a simulated annealing heuristic that finds a near-optimal solution. Random problems are generated for examining the effectiveness of this heuristic. [ABSTRACT FROM AUTHOR]

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Self-adaptation and self-organization (SASO) have been introduced to the management of technical systems as an attempt to improve robustness and administrability. In particular, both mechanisms adapt the system's structure and behavior in response to dynamics of the environment and internal or external disturbances. By now, adaptivity has been considered to be fully desirable. This position paper argues that too much adaptation conflicts with goals such as stability and user acceptance. Consequently, a kind of situation-dependent degree of adaptation is desired, which defines the amount and severity of tolerated adaptations in certain situations. As a first step into this direction, this position paper presents a quantification approach for measuring the current adaptation behavior based on generative, probabilistic models. The behavior of this method is analyzed in terms of three application scenarios: urban traffic control, the swidden farming model, and data communication protocols. Furthermore, we define a research roadmap in terms of six challenges for an overall measurement framework for SASO systems. [ABSTRACT FROM AUTHOR]