Twin-crane scheduling during seaside workload peaks with a dedicated handshake area

To enable the efficient division of labor in container yards, many large ports apply twin cranes, two identical automated stacking cranes each dedicated to one of the transfer zones on the seaside and landside. The use of a handshake area, a bay of containers that separates the dedicated areas of the two cranes, is a simple means to avoid crane interference. Inbound containers arriving in the transfer zone of one crane and dedicated to a stacking position of the other crane’s area are placed intermediately in the handshake area by the first crane and then taken over by the second crane, and vice versa for outbound containers. Existing research only evaluates simple heuristics and rule-based approaches for the coordination of twin cranes interconnected by a handshake area. For this setting, accounting for precedence constraints due to stacking containers in the handshake area, we derive exact solution procedures under a makespan minimization objective. In this way, a comprehensive computational evaluation is enabled, which benchmarks heuristics with optimal solutions and additionally compares alternative crane settings (i.e., without workload sharing and cooperation with flexible handover). We further provide insights into where to position the handshake area. Our results reveal that when planning is too simple (i.e., with a rule-based approach), optimality gaps become large, but with sophisticated optimization, the price of a simplified crane coordination via a handshake area is low.

A methodological framework to allocate storage space for outbound containers

The staking of containers on ideal locations within the yard is a tactical decision that affects the productivity of container terminals. The goal is to improve posterior loading and retrieval operations, to get better use of terminal resources. In this paper, we study how to allocate storage space for outbound containers in container terminals. A two-phase methodological framework is proposed. The first phase groups outbound containers into clusters of similar operational loading conditions. Then in a second phase, a bi-objective storage space assignment model is solved to determine the set of block-bays where groups of similar containers will be stored during the planning horizon. This study presents a double contribution. On one hand, it proposes a new methodological framework that combines operations research and data mining techniques to solve a storage space assignment problem for outbound containers. On the other hand, it analyzes the impact of three factors on four performance metrics used to evaluate the quality and quantity of alternative solutions to the problem of allocation of storage space for outbound containers. The experimental framework is composed of an experimental design study to assess the impact of three factors on four performance metrics used to assess the quality of the storage space assignment solutions, and a case study to validate the proposed approach. The experimental results reveal that the storage yard's capacity and the number of clusters used to group the containers destined to a vessel are the main factors that affect the number and quality of alternative solutions.

“Sell first, repent later.”

This chapter examines how Chelsea Piers facilities, located directly up the Westside Highway from Lower Manhattan, had served a major role in disaster response from the earliest hours of the 9/11 attacks. The piers offered water stations for people fleeing from downtown and became a key debarkation point for the waterborne evacuation, delivering more than 10,000 people off the island from its docks. Then, the following day, more than 30,000 people arrived to volunteer their help and connect with other New Yorkers. In the days that followed, thousands of uniformed personnel were fed in an events center at Pier 60, hundreds of rescuers slept and showered in Chelsea Piers facilities, and truckloads of donations and supplies were assembled and processed for delivery to the trade center site. By Wednesday, the flood of private citizens' donations had been supplemented with massive corporate contributions arriving in bulk. Meanwhile, the Coast Guard was confronted with two opposing missions: protecting potential targets of a second-wave attack and continuing commerce in a port that regularly handled approximately 6,000 inbound and outbound containers daily, the closure of which created complications worldwide.