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Tramp shipping companies are committed to transport a set of contracted cargoes and try to derive additional revenue from carrying optional spot cargoes. Here, we present a real life ship routing and scheduling problem for a shipping company operating in project shipping, a special segment of tramp shipping. This segment differs from more traditional tramp segments, as the cargoes are usually transported on a one-time basis. Because of the special nature of the cargoes, complicating requirements regarding stowage onboard the ships and cargo coupling must be considered while determining routes and schedules for the ships in the fleet. A mathematical model is presented and a tabu search heuristic is proposed to solve the problem. Computational results show that the tabu search heuristic provides optimal or near-optimal solutions in a reasonable amount of time, and that it can give significant improvements to manual planning for the shipping company.

In this work we demonstrate the use of co-simulation technology in the maritime industry through four relevant examples of applications based on the outcome of the knowledge-building project Virtual Prototyping of Maritime Systems and Operations (ViProMa). Increasing computational capabilities opens for extended use of simulators in the design processes. Even complex systems can now be analyzed at an early stage of the design process and even in real time using distributed simulation technology. We conduct an assessment of the need for co-simulation technology in the industry, present a short background in co-simulation technology, and provide a short summary of the major findings and deliverables in the ViProMa project (http://viproma.no). The four case studies presented in this work pinpoint different advantages of using co-simulations in the industry, such as combining different modeling and simulation tools, improving collaboration without revealing sensitive information by using black-box models, testing conceptual designs in a fast and consistent manner before initiating building processes, and verifying the interplay between hardware and software in the simulation environment in hardware in the loop (HIL) tests. All the case studies are simulated using the open source co-simulation software Coral developed in the project, using the Functional Mock-up Interface (FMI) standard, and the co-simulation software can be downloaded from the project's web site.