319 research outputs found

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

    Get PDF
    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

    Centrally Coordinated Schedules and Routes of Airport Shuttles with LAX Terminals as Application Area

    Get PDF
    Caltrans 65A0686 Task Order 070 USDOT Grant 69A3551747114Today\u2019s airport terminals face a critical problem of traffic congestion in the terminal area partly caused by uncoordinated shuttle operations. The congestion near pick-up and drop-off points negatively affects passenger traffic leading to unnecessary idling, delays and congestion with negative impact on air quality and mobility. The need for an intelligent shuttle management system becomes more urgent with the development of information technologies, battery electric shuttles and autonomous vehicles. In this project, we developed a centrally coordinated shuttle scheduling and routing management system for mixed fleets of diesel and electric shuttles using a digital twin of LAX to LA downtown traffic road network by optimizing the total combined cost of energy consumption and travel time. A Co-Simulation Optimization method is used to solve the problem. The objective is to reduce congestion at the designated pick up and drop off points due to different shuttles showing up at these points during overlapping time windows which exceed the curb capacity. Another objective is to integrate into the system mixed fleet of shuttles that include diesel and battery operated. The proposed centrally coordinated shuttle scheduling and routing management system takes into account the characteristics of mixed shuttle fleets and is shown to reduce the operational cost such as energy consumption and delays. The results also suggest the deployment of electric shuttles in order to reduce emissions and improve air quality further

    Sustainable supply chain management in the digitalisation era: The impact of Automated Guided Vehicles

    Get PDF
    Internationalization of markets and climate change introduce multifaceted challenges for modern supply chain (SC) management in the today's digitalisation era. On the other hand, Automated Guided Vehicle (AGV) systems have reached an age of maturity that allows for their utilization towards tackling dynamic market conditions and aligning SC management focus with sustainability considerations. However, extant research only myopically tackles the sustainability potential of AGVs, focusing more on addressing network optimization problems and less on developing integrated and systematic methodological approaches for promoting economic, environmental and social sustainability. To that end, the present study provides a critical taxonomy of key decisions for facilitating the adoption of AGV systems into SC design and planning, as these are mapped on the relevant strategic, tactical and operational levels of the natural hierarchy. We then propose the Sustainable Supply Chain Cube (S2C2), a conceptual tool that integrates sustainable SC management with the proposed hierarchical decision-making framework for AGVs. Market opportunities and the potential of integrating AGVs into a SC context with the use of the S2C2 tool are further discussed

    Internal report cluster 1: Urban freight innovations and solutions for sustainable deliveries (1/4)

    Get PDF
    Technical report about sustainable urban freight solutions, part 1 of

    Impact of Interdisciplinary Research on Planning, Running, and Managing Electromobility as a Smart Grid Extension

    Get PDF
    The smart grid is concerned with energy efficiency and with the environment, being a countermeasure against the territory devastations that may originate by the fossil fuel mining industry feeding the conventional power grids. This paper deals with the integration between the electromobility and the urban power distribution network in a smart grid framework, i.e., a multi-stakeholder and multi-Internet ecosystem (Internet of Information, Internet of Energy, and Internet of Things) with edge computing capabilities supported by cloud-level services and with clean mapping between the logical and physical entities involved and their stakeholders. In particular, this paper presents some of the results obtained by us in several European projects that refer to the development of a traffic and power network co-simulation tool for electro mobility planning, platforms for recharging services, and communication and service management architectures supporting interoperability and other qualities required for the implementation of the smart grid framework. For each contribution, this paper describes the inter-disciplinary characteristics of the proposed approaches

    Multi-population-based differential evolution algorithm for optimization problems

    Get PDF
    A differential evolution (DE) algorithm is an evolutionary algorithm for optimization problems over a continuous domain. To solve high dimensional global optimization problems, this work investigates the performance of differential evolution algorithms under a multi-population strategy. The original DE algorithm generates an initial set of suitable solutions. The multi-population strategy divides the set into several subsets. These subsets evolve independently and connect with each other according to the DE algorithm. This helps in preserving the diversity of the initial set. Furthermore, a comparison of combination of different mutation techniques on several optimization algorithms is studied to verify their performance. Finally, the computational results on the arbitrarily generated experiments, reveal some interesting relationship between the number of subpopulations and performance of the DE. Centralized charging of electric vehicles (EVs) based on battery swapping is a promising strategy for their large-scale utilization in power systems. In this problem, the above algorithm is designed to minimize total charging cost, as well as to reduce power loss and voltage deviation of power networks. The resulting algorithm and several others are executed on an IEEE 30-bus test system, and the results suggest that the proposed algorithm is one of effective and promising methods for optimal EV centralized charging
    corecore