An algorithm for the capacitated vehicle routing problem for picking application in manual warehouses

Given that warehouses play a central role in modern supply chains, this study proposes the application of an algorithm for the capacitated vehicle routing problem (CVRP) based on the two-index vehicle flow formulation developed by Baldacci, Hadjiconstantinou, and Mingozzi (2004) for picking purposes in manual warehouses. The study of Theys et al. (2010) is first used to represent the warehouse using a Steiner traveling salesman problem (TSP). Then, a calculation of the picking tour’s length is obtained applying the Manhattan distance. Finally, the algorithm for the CVRP is solved through a cutting plane with the addition of termination criteria related to the capacity of picker. The study analyzes four different warehouse configurations, processing five picking list each. The analysis is carried out exploiting the commercial software MATLAB®, to determine the solution that minimize distance of the order picking tour. The results obtained in MATLAB® show the effectiveness of the chosen algorithm applied to the context of manual order picking.

Towards a simulation-based decision support tool for container terminal layout design

Recently, seaports have paid much attention to container transportation by rail to evacuate huge container flow received by sea. In this line, Le Havre seaport, as the first French port in terms of containers’ traffic, plans to put into service a rail-road terminal near the Paris region. The main purpose of this new inland terminal is to restrict the intensive use of roads on the Le Havre-Paris corridor and achieve a better massification share of hinterland transportation. Containers are routed by train between Le Havre and this terminal and the last/first mile remains done by trucks. This paper aims to propose a decision support tool based on simulation for the layout design problem of this new terminal. This tool is tested using a set of scenarios and the obtained results are then discussed.

A conceptual model for assessing the impact of Internet-of-Things technologies for people with reduced mobility in airports

The European Union has regulated by law the elimination of barriers to guarantee the right to free movement, freedom of choice and non-discrimination of people with reduced mobility (PRM). This regulation also affects air transport. More specifically, airports of the member states must offer a quality assistance service to PRM, with the adequate human and technical resources to guarantee their rights. The changing characteristics of the operation of an airport (delays, cancellations, breakdowns, etc.) add great complexity to the design and management of a PRM service. Internet of Things (IoT) technologies pose a unique opportunity to integrate new services and solutions to deal with these problems. This work focuses on the use of modeling and simulation techniques for the evaluation of the impact of the incorporation of new IoT-based elements (such as autonomous vehicles, smart devices and 5G-enabled systems), for the improvement of the PRM service.

Simulation based evaluation of the capacity of Liuheng LNG Terminal

Liuheng LNG (Liquified Natural Gas) terminal is proposed to serve LNG carriers and LNG tank container ships. However, the capacity of this terminal may be limited by the long entrance channel and traffic rules for LNG transportation. Therefore, to evaluate the capacity of Liuheng LNG terminal, we establish an agent-based microscopic simulation model for ship operation (AMic-SMSO) to simulate the whole process of ship operation in and out of a port. We undertake a series of experiment scenarios to identify the bottlenecks and assess the throughput capability by analyzing waiting times, berth occupancies, and explore the effect of modifying the traffic rules on these indicators. The results show that this simulation model is a useful tool in determining whether traffic rules works well actually, especially for LNG terminal berth configuration plan.

A generic terminal macro simulation model for measuring operational performance

Strategic decision making linked to the development of intermodal transport terminals is marked by high complexity. Terminal operators need to cope with uncertainties and potential cascading impacts of decisions which were taken a long time ago. The aim of this paper is to present a generic System Dynamics (SD) model of a terminal’s operational performance. SD is used to capture a holistic view on a dynamic system, which is characterized by complex feedback structures, nonlinear processes, uncertainties and time delays. After introducing the qualitative Causal Loop Diagram (CLD), the underlying hypotheses are transposed into a quantitative Stock-and-Flow (S&F) model. The main components and its input data are explained. The generic model can be used as a decision support tool to bridge the gap from a detailed view to an understanding of longterm consequences. It offers multiple areas of application, which are briefly discussed.

Extended Reality, Intelligent Agents and Simulation to improve Efficiency, Safety and Security in Harbors and Port Plants

The paper introduces a new project devoted to develop a simulation-based solution for improving emergency planning and crisis management in critical infrastructures such as seaports and related terminal. The research aims to investigate the use of Artificial Intelligence and Simulation jointly with Extended Reality in this framework.

A multi-agent system with blockchain for container stacking and dispatching

Port Logistical Supply chains play a very important role in society. Their complex and adaptive behaviours promote the suggested applications of combining a multiagent system with blockchain for solving complex problems. Several technologies have been proven positively to work in logistics, however the concept of combining converging technologies such as blockchain with deep reinforcement multi agent is viewed as a novel approach to solving the complexity that is associated with many facets of logistics. A simulator was developed and tested for the problem of container stacking. The simulation results indicate a more robust approach to currently used tools and methods.

Stochastic floating quay crane scheduling on offshore platforms: a simheuristic approach

The scheduling of quay cranes is a core logistics challenge that affects significantly the loading and unloading time of a vessel berthed at a container terminal. In this paper, we study the Stochastic Floating Quay Crane Scheduling Problem involving cranes situated on the quay of an offshore modular platform. Specifically, we consider the case in which each crane is situated on a different module of the platform, thereby confining its operation range. Additionally, we assume stochastic crane productivity rates due to the effect of the offshore wind. To tackle the problem, we propose a simheuristic framework, which combines Iterated Local Search with Monte Carlo Sampling into a joint collaborative scheme. The main objective is to minimize the expected completion time of the loading and unloading process taking into account precedence, nonsimultaneity, non-crossing, and spatial constraints of the problem at hand. The performance of the proposed simheuristic is investigated on a set of established problem instances across different configuration parameters and under various real-world environmental scenarios offering insightful conclusions.

Realization of food defense and food security standards in Polish maritime transport

This article touches on the issue of Food Defense and Food Security in Polish maritime transport. It seems indispensable to refer to the food defense as any action that the company must take to prevent the intentional contamination of food products by biological, chemical, physical or radiological factors which cannot be expected based on hazard analysis and which may arise in connection with human activities as a source of contamination (FDA). Temperature-controlled food transport is one of the most critical elements in today's supply chain, which is reflected in an increase in the demand for fresh and frozen products. In the case of sea transport, this will require temperature control in refrigerated containers. The effect of research on the impact of the stream of descending air and its free passage on the duration of storage of natural food products, which are presented in the article, are guidelines contained in military procedures.

Conceptual model of supply chain in risky environment: case study

The supply chain faces uncertainties, especially with the flow of products and information that may affect the productivity, revenue and competitive advantages of many organizations. It is therefore necessary for these organizations to be agile and resilient enough to meet with these uncertainties so that they may be managed appropriately or even avoided. In a publication by Mensah et.al (2014), the authors introduce a theoretical approach where the „conceptualization of risks for subsequent simulation-based analysis‟ is evaluated. This includes the description of „a generic conceptual model of a retail node‟ followed by the introduction of performance indicators relevant for simulation base analysis. Hence, a concept for further studies from a practical point of view has now arisen. This article therefore introduces a new case study where the flow of products in a real company is conceptualized for simulation base analysis to raise the awareness of the organization in case of uncertainties.