iTETRIS: An Integrated Wireless and Traffic Platform for Real-Time Road Traffic Management Solutions

Wireless vehicular cooperative systems have been identified as an attractive solution to improve road traffic management, thereby contributing to the European goal of safer, cleaner, and more efficient and sustainable traffic solutions. V2V-V2I communication technologies can improve traffic management through real-time exchange of data among vehicles and with road infrastructure. It is also of great importance to investigate the adequate combination of V2V and V2I technologies to ensure the continuous and costefficient operation of traffic management solutions based on wireless vehicular cooperative solutions. However, to adequately design and optimize these communication protocols and analyze the potential of wireless vehicular cooperative systems to improve road traffic management, adequate testbeds and field operational tests need to be conducted. Despite the potential of Field Operational Tests to get the first insights into the benefits and problems faced in the development of wireless vehicular cooperative systems, there is yet the need to evaluate in the long term and large dimension the true potential benefits of wireless vehicular cooperative systems to improve traffic efficiency. To this aim, iTETRIS is devoted to the development of advanced tools coupling traffic and wireless communication simulators

On green routing and scheduling problem

The vehicle routing and scheduling problem has been studied with much interest within the last four decades. In this paper, some of the existing literature dealing with routing and scheduling problems with environmental issues is reviewed, and a description is provided of the problems that have been investigated and how they are treated using combinatorial optimization tools

Optimal Routing for Safe Construction and Demolition Waste Transportation: A CVaR Criterion and Big Data Analytics Approach

Rapid urbanisation worldwide, especially in developing countries and areas, has led to the generation of large amounts of construction and demolition waste (C&DW). The resultant transportation demands pose severe threats to safe transportation and secure city operation. By considering the low-probability–high-consequence nature of C&DW traffic accidents and the effectiveness of route optimisation in transportation risk control, a risk-averse project was implemented. Furthermore, an optimal routing model based on the conditional value at risk (CVaR) criterion is proposed. The model considered various risk-averse attitudes of decision-makers. For practicality and for strongly supporting policy-making, big data technology, including the construction of multistructure databases and in-depth analysis, was applied to achieve the proposed CVaR routing model. Therefore, the present study extended the CVaR method to optimal routing design in the field of safe urban C&DW transportation and integrated the optimal model with big data technology

Applications of Genetic Algorithm and Its Variants in Rail Vehicle Systems: A Bibliometric Analysis and Comprehensive Review

Railway systems are time-varying and complex systems with nonlinear behaviors that require effective optimization techniques to achieve optimal performance. Evolutionary algorithms methods have emerged as a popular optimization technique in recent years due to their ability to handle complex, multi-objective issues of such systems. In this context, genetic algorithm (GA) as one of the powerful optimization techniques has been extensively used in the railway sector, and applied to various problems such as scheduling, routing, forecasting, design, maintenance, and allocation. This paper presents a review of the applications of GAs and their variants in the railway domain together with bibliometric analysis. The paper covers highly cited and recent studies that have employed GAs in the railway sector and discuss the challenges and opportunities of using GAs in railway optimization problems. Meanwhile, the most popular hybrid GAs as the combination of GA and other evolutionary algorithms methods such as particle swarm optimization (PSO), ant colony optimization (ACO), neural network (NN), fuzzy-logic control, etc with their dedicated application in the railway domain are discussed too. More than 250 publications are listed and classified to provide a comprehensive analysis and road map for experts and researchers in the field helping them to identify research gaps and opportunities

Enhancing the performance of automated guided vehicles through reliability, operation and maintenance assessment

Automated guided vehicles (AGVs), a type of unmanned moving robots that move along fixed routes or are directed by laser navigation systems, are increasingly used in modern society to improve efficiency and lower the cost of production. A fleet of AGVs operate together to form a fully automatic transport system, which is known as an AGV system. To date, their added value in efficiency improvement and cost reduction has been sufficiently explored via conducting in-depth research on route optimisation, system layout configuration, and traffic control. However, their safe application has not received sufficient attention although the failure of AGVs may significantly impact the operation and efficiency of the entire system. This issue becomes more markable today particularly in the light of the fact that the size of AGV systems is becoming much larger and their operating environment is becoming more complex than ever before. This motivates the research into AGV reliability, availability and maintenance issues in this thesis, which aims to answer the following four fundamental questions: (1) How could AGVs fail? (2) How is the reliability of individual AGVs in the system assessed? (3) How does a failed AGV affect the operation of the other AGVs and the performance of the whole system? (4) How can an optimal maintenance strategy for AGV systems be achieved? In order to answer these questions, the method for identifying the critical subsystems and actions of AGVs is studied first in this thesis. Then based on the research results, mathematical models are developed in Python to simulate AGV systems and assess their performance in different scenarios. In the research of this thesis, Failure Mode, Effects and Criticality Analysis (FMECA) was adopted first to analyse the failure modes and effects of individual AGV subsystems. The interactions of these subsystems were studied via performing Fault Tree Analysis (FTA). Then, a mathematical model was developed to simulate the operation of a single AGV with the aid of Petri Nets (PNs). Since most existing AGV systems in modern industries and warehouses consist of multiple AGVs that operate synchronously to perform specific tasks, it is necessary to investigate the interactions between different AGVs in the same system. To facilitate the research of multi-AGV systems, the model of a three-AGV system with unidirectional paths was considered. In the model, an advanced concept PN, namely Coloured Petri Net (CPN), was creatively used to describe the movements of the AGVs. Attributing to the application of CPN, not only the movements of the AGVs but also the various operation and maintenance activities of the AGV systems (for example, item delivery, corrective maintenance, periodic maintenance, etc.) can be readily simulated. Such a unique technique provides us with an effective tool to investigate larger-scale AGV systems. To investigate the reliability, efficiency and maintenance of dynamic AGV systems which consist of multiple single-load and multi-load AGVs traveling along different bidirectional routes in different missions, an AGV system consisting of 9 stations was simulated using the CPN methods. Moreover, the automatic recycling of failed AGVs is studied as well in order to further reduce human participation in the operation of AGV systems. Finally, the simulation results were used to optimise the design, operation and maintenance of multi-AGV systems with the consideration of the throughputs and corresponding costs of them.The research reported in this thesis contributes to the design, reliability, operation, and maintenance of large-scale AGV systems in the modern and rapidly changing world.</div

Airships for Logistics Case Study

Since the beginning of times, humanity has needed transportation of goods, people or animals. As technology advanced and changed, the user's demand was modified. Hence new means of transportation started arising and airships, for instance, have been getting an increasing amount of attention, mostly due to the fact that aeronautical entities have been concerned with adopting environmentally friendly technologies. In this century, airships started to have their fair share of distinct uses: advertisement, surveillance, monitoring, investigation and tourism. In this dissertation another use was analysed, this was logistics freight transportation to inquire if it would be a practical alternative to road transportation and if it could counter some of the nowadays’ restraints found in logistics such as poor street conditions, interdiction to the circulation of some vehicles in certain areas, and traffic congestion. In this thesis, it was shown how using airships for freight and consequently its role in terms of logistics’ distribution is feasible. To do so, the vital elements of a business plan and model were analysed, the network route optimisation methodologies were studied and an approach to a case study based on a real company’s operation in the national market was made. The results confirmed the viability of the initial assumptions corroborating the advantages (along with the challenges) of using airships in the logistics chain of freight transportation.Desde os tempos mais primordiais, o Homem teve a necessidade de transportar bens, pessoas ou animais. Com os avanços e mudanças da tecnologia, também a procura de transporte por parte dos utilizadores sofreu alterações. Neste sentido surgiram novos meios de transporte e os dirigíveis, por exemplo, começaram a ser alvo de um crescente nível de atenção, sobretudo devido ao facto de as entidades aeronáuticas terem uma maior preocupação com a adoção de tecnologias amigas do ambiente. Neste século, os dirigíveis começaram a ter a sua quota-parte nos mais diversos usos: publicidade, vigilância, monitorização, investigação e turismo. Nesta dissertação foi analisado um outro uso, o transporte de carga, para perceber se este poderia ser uma alternativa prática relativamente ao transporte rodoviário e se assim se poderia contrariar algumas das restrições encontradas no que toca à logística tais como: vias rodoviárias em mau estado de conservação, interdições à circulação de alguns tipos de veículos em certas áreas, e congestionamento de tráfego. Neste trabalho mostrou-se como a utilização de dirigíveis para o transporte de carga e, consequentemente, o seu papel em termos da logística de distribuição, é exequível. Para tal, foram analisados os elementos essenciais a um modelo e plano de negócios, estudadas as metodologias de otimização em rede de possíveis rotas, e abordado um caso de estudo com base na operação real de uma empresa no mercado nacional. Os resultados confirmaram a viabilidade dos pressupostos iniciais corroborando as vantagens (mas também os desafios) da utilização de dirigíveis na cadeia logística do transporte de carga

Online Optimisation of Casualty Processing in Major Incident Response

Recent emergency response operations to Mass Casualty Incidents (MCIs) have been criticised for a lack of coordination, implying that there is clear potential for response operations to be improved and for corresponding benefits in terms of the health and well-being of those affected by such incidents. In this thesis, the use of mathematical modelling, and in particular optimisation, is considered as a means with which to help improve the coordination of MCI response. Upon reviewing the nature of decision making in MCIs and other disaster response operations in practice, this work demonstrates through an in-depth review of the available academic literature that an important problem has yet to be modelled and solved using an optimisation methodology. This thesis involves the development of such a model, identifying an appropriate task scheduling formulation of the decision problem and a number of objective functions corresponding to the goals of the MCI response decision makers. Efficient solution methodologies are developed to allow for solutions to the model, and therefore to the MCI response operation, to be found in a timely manner. Following on from the development of the optimisation model, the dynamic and uncertain nature of the MCI response environment is considered in detail. Highlighting the lack of relevant research considering this important aspect of the problem, the optimisation model is extended to allow for its use in real-time. In order to allow for the utility of the model to be thoroughly examined, a complementary simulation is developed and an interface allowing for its communication with the optimisation model specified. Extensive computational experiments are reported, demonstrating both the danger of developing and applying optimisation models under a set of unrealistic assumptions, and the potential for the model developed in this work to deliver improvements in MCI response operations

Comprehensive review on risk assessment methodologies for HAZMAT transportation between 1995-2015

Issue related to safety, health and environmental has become major priority to be concerned of in the transportation of hazardous materials (HAZMAT) worldwide. Due to the high risk that entailed in the operation of HAZMAT transportation, many accidents in this industry have been reported which include chemicals spillage, fire and explosion. In order to quantify the degree of hazards and risks of these accidents, various assessment methods have been introduced either by the academia, the industry as well as the authority. The methods present various approaches for the assessment, ranging from a simple to highly complicated ones depending on the purpose of the assessment and the available resources and constraints. To date there is yet any study conducted to review those available methods. This paper intends to present a comprehensive review of the existing methods for hazards and risks assessment of HAZMAT transportation between years 1995-2015 which considers road, marine, railway, air and pipeline system. Based on careful screening of the abundance of methods available, 151 of them were selected – that is those specifically meant for hazards and risks assessment of HAZMAT transportation only. The methods are reviewed in terms of the types of assessment; either qualitative, quantitative or hybrid techniques, as well as their specific application in different mode of transportation. Also, statistical analysis was performed to determine the trend of past publications regarding on the type of journal, year of publication and also financial support received in the context of hazard and risk assessment of HAZMAT transportation

SYSTEM MODEL FOR AUTONOMOUS ROAD FREIGHT TRANSPORTATION

Emerging info-communication and vehicle technologies (especially vehicle automation) facilitate evolvement of autonomous road freight transportation. The entire transport system and its operation undergo a major change. New service concepts are growing and the existing ones are being transformed. The changing is particularly significant in city logistics. However, there are debates about the ways of automation of processes targeting improvement of capacity utilisation and decrease of expenditures. The main research questions of the paper are therefore: what properties of the future autonomous freight transportation are presumed; what system structure is to be constructed and how the system is to be operated? After introducing the basic notions and reviews of the current systems and developments, the shifting from traditional freight transportation to autonomous system is investigated by several aspects. A system- and process-oriented analytical modelling method has been applied. The main system constituents and their connections are modelled. Finally, we elaborate the operational model of road freight transportation, which is applicable principally in metropolitan areas. In conclusion, the presented results appoint the research and innovation trends towards the automation of freight transportation