2,233 research outputs found
Volumetric Techniques for Product Routing and Loading Optimisation in Industry 4.0: A Review
Industry 4.0 has become a crucial part in the majority of processes, components, and related modelling, as well as predictive tools that allow a more efficient, automated and sustainable approach to industry. The availability of large quantities of data, and the advances in IoT, AI, and data-driven frameworks, have led to an enhanced data gathering, assessment, and extraction of actionable information, resulting in a better decision-making process. Product picking and its subsequent packing is an important area, and has drawn increasing attention for the research community. However, depending of the context, some of the related approaches tend to be either highly mathematical, or applied to a specific context. This article aims to provide a survey on the main methods, techniques, and frameworks relevant to product packing and to highlight the main properties and features that should be further investigated to ensure a more efficient and optimised approach
An online packing heuristic for the three-dimensional container loading problem in dynamic environments and the Physical Internet
In this paper, we consider the online three-dimensional container loading problem. We develop a novel online packing algorithm to solve the three-dimensional bin packing problem in the online case where items are not know well in advance and they have to be packed in real-time when they ar-rive. This is relevant in many real-world scenarios such as automated cargo loading in warehouses. This is also relevant in the new logistics model of Physical Internet. The effectiveness of the online packing heuristic is evalu-ated on a set of generated data. The experimental results show that the algo-rithm could solve the 3D container loading problems in online fashion and is competitive against other algorithms both in the terms of running time, space utilization and number of bins
Simultaneous Planning of Liner Ship Speed Optimization, Fleet Deployment, Scheduling and Cargo Allocation with Container Transshipment
Due to a substantial growth in the world waterborne trade volumes and drastic
changes in the global climate accounted for CO2 emissions, the shipping
companies need to escalate their operational and energy efficiency. Therefore,
a multi-objective mixed-integer non-linear programming (MINLP) model is
proposed in this study to simultaneously determine the optimal service
schedule, number of vessels in a fleet serving each route, vessel speed between
two ports of call, and flow of cargo considering transshipment operations for
each pair of origin-destination. This MINLP model presents a trade-off between
economic and environmental aspects considering total shipping time and overall
shipping cost as the two conflicting objectives. The shipping cost comprises of
CO2 emission, fuel consumption and several operational costs where fuel
consumption is determined using speed and load. Two efficient evolutionary
algorithms: Nondominated Sorting Genetic Algorithm II (NSGA-II) and Online
Clustering-based Evolutionary Algorithm (OCEA) are applied to attain the
near-optimal solution of the proposed problem. Furthermore, six problem
instances of different sizes are solved using these algorithms to validate the
proposed model.Comment: 28 pages, 10 figure
Discrete-Event Control and Optimization of Container Terminal Operations
This thesis discusses the dynamical modeling of complex container terminal operations. In the current literature, the systems are usually modeled in static way using linear programming techniques. This setting does not completely capture the dynamic aspects in the operations, where information about external factors such as ships and trucks arrivals or departures and also the availability of terminal's equipment can always change. We propose dynamical modeling of container terminal operations using discrete-event systems (DES) modeling framework. The basic framework in this thesis is the DES modeling for berth and quay crane allocation problem (BCAP) where the systems are not only dynamic, but also asynchronous. We propose a novel berth and QC allocation method, namely the model predictive allocation (MPA) which is based on model predictive control principle and rolling horizon implementation. The DES models with asynchronous event transition is mathematically analyzed to show the efficacy of our method. We study an optimal input allocation problem for a class of discrete-event systems with dynamic input sequence (DESDIS). We show that in particular, the control input can be obtained by the minimization/maximization of the present input sequence only. We have shown that the proposed approach performed better than the existing method used in the studied terminal and state-of-the-art methods in the literature
Container Hinterland Drayage - On the Simultaneous Transportation of Containers Having Different Sizes
In an intermodal transportation chain drayage is the term used for the movement by truck of cargo that is filled in a loading unit. The most important intermodal transportation chain is the intermodal container transportation, in which containers represent the loading unit for cargo. Cost effectiveness constitutes a general problem of drayage operations. A major cost driver within container transportation chains is the movement and repositioning of empty containers. The present thesis investigates the potential to reduce drayage costs. Two solution methodologies are developed for operating a fleet of trucks that transports containers of different sizes, which addresses a recent gap in research in seaport hinterland regions
Shipping Configuration Optimization with Topology-Based Guided Local Search for Irregular Shaped Shipments
Manufacturer that uses containers to ship products always works to optimize the space inside the containers. Container loading problems (CLP) are widely encountered in forms of raw material flow and handling, product shipments, warehouse management, facility floor planning, as well as strip-packing nesting problems.Investigations and research conducted two decades ago were logistic orientated, on the basis of the empirical approaches
An Object-oriented Environment for Developing Finite Element Codes for Multi-disciplinary Applications
The objective of this work is to describe the design and implementation of a framework for building multi-disciplinary finite element programs. The main goals are generality, reusability, extendibility, good performance and memory efficiency. Another objective is preparing the code structure for team development to ensure the easy collaboration of experts in different fields in the development of multi-disciplinary applications.
Kratos, the framework described in this work, contains several tools for the easy implementation of finite element applications and also provides a common platform for the natural interaction of different applications. To achieve this, an innovative variable base interface is designed and implemented. This interface is used at different levels of abstraction and showed to be very clear and extendible. A very efficient and flexible data structure and an extensible IO are created to overcome difficulties in dealing with multi-disciplinary problems. Several other concepts in existing works are also collected and adapted to coupled problems. The use of an interpreter, of different data layouts and variable number of dofs per node are examples of such approach.
In order to minimize the possible conflicts arising in the development, a kernel and application approach is used. The code is structured in layers to reflect the working space of developers with different fields of expertise. Details are given on the approach chosen to increase performance and efficiency. Examples of application of Kratos to different multidisciplinary problems are presented in order to demonstrate the applicability and efficiency of the new object oriented environment
Quantum Computing in Logistics and Supply Chain Management an Overview
The work explores the integration of quantum computing into logistics and
supply chain management, emphasising its potential for use in complex
optimisation problems. The discussion introduces quantum computing principles,
focusing on quantum annealing and gate-based quantum computing, with the
Quantum Approximate Optimisation Algorithm and Quantum Annealing as key
algorithmic approaches. The paper provides an overview of quantum approaches to
routing, logistic network design, fleet maintenance, cargo loading, prediction,
and scheduling problems. Notably, most solutions in the literature are hybrid,
combining quantum and classical computing. The conclusion highlights the early
stage of quantum computing, emphasising its potential impact on logistics and
supply chain optimisation. In the final overview, the literature is
categorised, identifying quantum annealing dominance and a need for more
research in prediction and machine learning is highlighted. The consensus is
that quantum computing has great potential but faces current hardware
limitations, necessitating further advancements for practical implementation
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