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A fleet of drones is considered in the routing problems with an offshore drone base station, considering the simultaneous movements of drones and ships. A model, entitled meeting model, between a drone and a moving ship is devised, and an extended model is developed based on the vehicle routing problem model. A genetic algorithm based on a sequential insert heuristic (SIH) is designed to solve the model as a holistic framework with two strategies to determine the sequential assignments of ships to drones, namely, the D r o n e B y D r o n e , and S h i p B y S h i p strategies. The proposed models and solution algorithms are demonstrated and verified by experiments. Numerical studies show that the D r o n e B y D r o n e strategy can overperform the S h i p B y S h i p strategy regarding traveling distances. In addition, when considering the simultaneous movement of the ship and drone, improving the drone flying speeds can reduce the flying time of drones rather than optimizing the ship's moving speed. The managerial implications and possible extensions are discussed based on modeling and experimental studies. [ABSTRACT FROM AUTHOR]

At automated container terminals (ACTs), twin automated stacking cranes (ASCs) can carry out the tasks--store and retrieve containers simultaneously in a yard block using a handshake bay, where a primary ASC stacks the container at the handshake bay and the other crane carries it to the destination bay. Although the handshake bay increases the degree of crane utilization, the ASCs will interfere with each other at the bay, decreasing the stacking efficiency. This study formulates a mixed-integer linear program (MILP) to position the handshake bay and simultaneously schedule the twin ASCs to minimize the tasks' makespan. The proposed formulation considers the safe time interval to avoid crane collisions during adjacent crane movements. To solve the model, we developed a random-key genetic algorithm with a priority-based decoding scheme to optimize the task sequences and tasks assigned to the cranes. The priority-based GA can always generate feasible solutions by ranking the container-handling tasks. Numerical experiments prove that the safe temporal interval affects the makespan and the handshake bay's position. An optimal handshake bay reduces 35% of the makespan compared with a nonoptimal bay, and the proposed algorithm is competitive compared with the on-the-shelf MILP solver and can solve medium- and large-scale instances in short computing time with gaps lower than 5% compared with ideal solutions., Author(s): Zhi-Hua Hu (corresponding author) [1,2]; Xi-Dan Tian [1,2]; Yu-Qi Yin [2]; Chen Wei [2] 1. Introduction Globalization promotes container transportation through seaborne shipping that undertakes 90% of the world [...]

Cold chain brokenness is a source of safety problems related to cool cargos. The cold chain logistics companies (CCLCs) can share their logistics information with governments to provide cold chain transparency, traceability, and brokenness proofs. The governments administrate the information sharing of the companies to prevent social loss and recovery costs when disastrous events happen. In this research, we apply the evolutionary game theory to examine the mutual interactions between the CCLCs (whose behavioral space consists of two strategies, information sharing and not) and the governments (whose behavioral space consists of two strategies, administration and not). First, we formulate the interactions as an evolutionary game model considering the governments and CCLCs as two interacted populations, whose dynamics are impacted by some parameters (including administration cost, penalty, subsidy, revenues, and logistics costs). Second, we devise eight propositions to examine the parameter impacts, the equilibrium points, and the evolutionary stable strategies (ESSs). Third, eight propositions, the effects of critical parameters on the ESSs, their dynamics and sensitivities are then simulated and investigated numerically. As results in theoretical and numerical analysis, high administration cost is harmful to advocate long-term information sharing strategy; subsidization is useful to encourage the companies for adopting information sharing strategy but is absent for long-term impacts; penalty cost is critical to administrate the CCLCs; high revenue of the CCLCs without information sharing strategy will challenge the governments' administration mechanism. We finally discuss the contributions of information sharing to avoiding cold chain brokenness, as well as the future research directions considering the three pillars of sustainability for cold chains. [ABSTRACT FROM AUTHOR]