Arc routing problems: A review of the past, present, and future

[EN] Arc routing problems (ARPs) are defined and introduced. Following a brief history of developments in this area of research, different types of ARPs are described that are currently relevant for study. In addition, particular features of ARPs that are important from a theoretical or practical point of view are discussed. A section on applications describes some of the changes that have occurred from early applications of ARP models to the present day and points the way to emerging topics for study. A final section provides information on libraries and instance repositories for ARPs. The review concludes with some perspectives on future research developments and opportunities for emerging applicationsThis research was supported by the Ministerio de Economia y Competitividad and Fondo Europeo de Desarrollo Regional, Grant/Award Number: PGC2018-099428-B-I00. The Research Council of Norway, Grant/Award Numbers: 246825/O70 (DynamITe), 263031/O70 (AXIOM).Corberán, Á.; Eglese, R.; Hasle, G.; Plana, I.; Sanchís Llopis, JM. (2021). Arc routing problems: A review of the past, present, and future. Networks. 77(1):88-115. https://doi.org/10.1002/net.21965S8811577

Optimization-Based Energy Management for Multi-energy Maritime Grids

This open access book discusses the energy management for the multi-energy maritime grid, which is the local energy network installed in harbors, ports, ships, ferries, or vessels. The grid consists of generation, storage, and critical loads. It operates either in grid-connected or in islanding modes, under the constraints of both power system and transportation system. With full electrification, the future maritime grids, such as all-electric ships and seaport microgrids, will become “maritime multi-energy system” with the involvement of multiple energy, i.e., electrical power, fossil fuel, and heating/cooling power. With various practical cases, this book provides a cross-disciplinary view of the green and sustainable shipping via the energy management of maritime grids. In this book, the concepts and definitions of the multi-energy maritime grids are given after a comprehensive literature survey, and then the global and regional energy efficiency policies for the maritime transportation are illustrated. After that, it presents energy management methods under different scenarios for all-electric ships and electrified ports. At last, the future research roadmap are overviewed. The book is intended for graduate students, researchers, and professionals who are interested in the energy management of maritime transportation

Modelling, Monitoring, Control and Optimization for Complex Industrial Processes

This reprint includes 22 research papers and an editorial, collected from the Special Issue "Modelling, Monitoring, Control and Optimization for Complex Industrial Processes", highlighting recent research advances and emerging research directions in complex industrial processes. This reprint aims to promote the research field and benefit the readers from both academic communities and industrial sectors

Time Localization of Abrupt Changes in Cutting Process using Hilbert Huang Transform

Cutting process is extremely dynamical process influenced by different phenomena such as chip formation, dynamical responses and condition of machining system elements. Different phenomena in cutting zone have signatures in different frequency bands in signal acquired during process monitoring. The time localization of signal’s frequency content is very important. An emerging technique for simultaneous analysis of the signal in time and frequency domain that can be used for time localization of frequency is Hilbert Huang Transform (HHT). It is based on empirical mode decomposition (EMD) of the signal into intrinsic mode functions (IMFs) as simple oscillatory modes. IMFs obtained using EMD can be processed using Hilbert Transform and instantaneous frequency of the signal can be computed. This paper gives a methodology for time localization of cutting process stop during intermittent turning. Cutting process stop leads to abrupt changes in acquired signal correlated to certain frequency band. The frequency band related to abrupt changes is localized in time using HHT. The potentials and limitations of HHT application in machining process monitoring are shown

Modeling and optimal control of multiphysics problems using the finite element method

Interdisciplinary research like constrained optimization of partial differential equations (PDE) for trajectory planning or feedback algorithms is an important topic. Recent technologies in high performance computing and progressing research in modeling techniques have enabled the feasibility to investigate multiphysics systems in the context of optimization problems. In this thesis a conductive heat transfer example is developed and techniques from PDE constrained optimization are used to solve trajectory planning problems. In addition, a laboratory experiment is designed to test the algorithms on a real world application. Moreover, an extensive investigation on coupling techniques for equations arising in convective heat transfer is given to provide a basis for optimal control problems regarding heating ventilation and air conditioning systems. Furthermore a novel approach using a flatness-based method for optimal control is derived. This concept allows input and state constraints in trajectory planning problems for partial differential equations combined with an efficient computation. The stated method is also extended to a Model Predictive Control closed-loop formulation. For illustration purposes, all stated problems include numerical examples

A Tabu Search, Augment-Merge Heuristic to Solve the Stochastic Location Arc Routing Problem

The location arc routing problem (LARP) is a network optimization problem combining strategic facility location decisions and tactical or operational vehicle routing decisions for customer demand located on arcs of a network. The LARP seeks to locate facilities, or depots, and create vehicle delivery routes to minimize costs. The total cost is comprised of three components: fixed facility locations costs, fixed route creation (or vehicle acquisition) costs, and variable arc traversal costs. The applications of the LARP are varied and often include public services such as mail delivery, garbage collection, and street sweeping. In all of these applications, the magnitude of customer demand may be unknown at the outset of the problem and realized uncertainty can greatly affect the final solution. To the author’s knowledge, there is currently no discussion of formulating or solving a LARP with uncertainty. This paper presents an iterative tabu search, augment-merge heuristic to solve the LARP with stochastic customer demand. Each realization of customer demand for a particular network, represented by an individual scenario, was generated using the deterministic mval instances (with 24-50 nodes and 44-138 arcs) created by Hashemi Doulabi and Seifi (2013) and a truncated normal probability distribution. The tabu search phase handles the depot location decisions and chooses a set of depots to be used across all scenarios. The augment-merge phase creates a set of vehicle routes for each scenario. One-third of the initial experiments resulted in stochastic solution costs less than their deterministic counterparts indicating the promising value of considering customer demand uncertainty using the proposed stochastic LARP algorithm

Heuristic scheduling algorithms for dedicated and flexible manufacturing systems

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