An early-stage design model for estimating ship evacuation patterns using the ship-centric Markov decision process

An early-stage design model is presented that estimates personnel locations on board a vessel during times of evacuation. This model takes into account various levels of uncertainty and pain that individuals may feel while heading toward safety, while simultaneously not requiring highly detailed information regarding the vessel layout. This makes this model suitable for analysis during early stages of design. To do this, principal eigenvector analysis is applied to the ship-centric Markov decision process model. Principal eigenvector analysis provides a leading indicator metric for forecasting and quantifying locations of individuals when coupled with the ship-centric Markov decision process model. For evacuation models suited for later stages of design, full temporal simulations may be required to understand long-term implications of personnel movement. This article proposes an alternative method that is able to identify some of these implications while not requiring full details of the vessel layout nor temporal simulations. To do this, a common theorem in Markov theory is applied that defines how the principal eigenvector represents the long-term steady-state behavior of the system. Metrics are defined that quantify the probability that an individual will congregate at specific locations on the vessels and highlight sensitivities to long-term behavior. A case study of a simplified vessel layout is presented that examines decision-making regarding ship egress analysis and general arrangements design. The results highlight specific areas of interest that cause significant changes to where individuals congregate and the probability they arrive safely at the exit. Sensitivity studies are performed varying the uncertainty in the movement of the individuals, how much pain they are experiencing, and one example where a passageway is blocked.Ship Design, Production and Operation

Integrating detailed layout generation with logistic performance assessment to improve layout insights in early stage warship design

These operational processes are of a logistical nature. Therefore these processes have a significant impact on the arrangement of these ships. Early stage design efforts are aimed to understand the interaction between the layout and the operational processes aboard these ships to gain timely design insights to inform the decision-making process.Therefore, sufficiently detailed concept designs are to be generated by naval architects and analysed to derisk requirements. While various tools have been developed to support naval architects in generating layouts with various level of detail, the detailed evaluation of operational performance is typically postponed to the stage that only little change to the design is possible. While various research developed tools to analyse operational performance, there is still a mismatch between the level of detail of layouts and the level of detail of operational performance analysis. Hence, the naval architect’s expertise is crucial to develop concept designs with acceptable operational performance.To address this mismatch between layout generation and evaluation, this paper proposes an integrated method that allows naval architects to concurrently generate and evaluate sufficiently detailed layouts. A test case is presented in which the proposed method is used to generate a detailed layout for a Landing Platform Dock (LPD) and evaluate this layout based on operational processes.The test case shows that the method can indeed be used to generate and evaluate detailed layouts of internal layout and process driven ships. However, the implementation of tooling for this method proved to be challenging and thus requires further attention. Nonetheless, the test case indicates that the proposed method will improve early stage ship design by helping naval architects to better understand the complex interrelation between layout and operational processes.Ship Design, Production and Operation

The Design Knowledge Management Square - a Framework for Early Stage Complex Ship Design

This paper presents and demonstrates a new design thinking framework for early stage complex ship design, called the Design Knowledge Management Square (DKMS) framework. The DKMS framework provides a structure that explicitly incorporates the collaborative nature of complex ship design, contrary to other models or frameworks that primarily focus on the technical integration of tools and methods to describe early stage complex ship design. The DKMS framework is applied to three case studies: 1) multi-disciplinary early stage design of complex ships, 2) the integration of concept design generation and analysis methods, and 3) the application of design rationale to support collaborative design decision-making. The case studies show that the DKMS framework provides added value by explicitly describing both the collaborative and technical nature of complex ship design. Thereby the framework helps to analyse, support, and understand complex ship design.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Ship Design, Production and Operation