Sigurd Solheim Pettersen

Handling commercial, operational and technical uncertainty in early stage offshore ship design

In this paper, we assess state-of-the-art methods for handling aspects of technical, commercial and operational uncertainty in the early stages of offshore ship design. Uncertainty affects the lifecycle performance of a ship in a complex manner, which is difficult to assess in the early design process. We approach this problem by decomposing uncertainty into technical, commercial and operational aspects, and investigate how it can be identified, modelled and handled. Methods discussed include design structure matrix, tradespace exploration and evaluation methods, real options theory, stochastic optimization, and system dynamics. Strategies for handling uncertainty discussed include margins, and specific system lifecycle properties “-ilities”. We argue that a decomposition of uncertainty facilitates the use of current methods and approaches for decision-making in early stage ship design.

Assessing flexible offshore construction vessel designs combining real options and epoch-era analysis

ABSTRACT Recent events in offshore oil and gas markets show the need for elaborate treatments of uncertainty throughout the design process and lifecycle management of maritime engineering systems. Offshore construction vessels are subject to uncertainty stemming from both economic factors modelled as stochastic processes, and from discrete factors like regulations and contract requirements. We present a simulation framework for valuation of flexible offshore construction vessels incorporating real options analysis and epoch-era analysis. Based on compliance with a set of contracts and the potential revenue to be earned from these contracts, the model maximizes expected net present value for each contract period. Benchmarking a flexible design of an offshore construction vessel against an inflexible design, we estimate the value of flexibility and find strategies for managing the design through the lifecycle. The results show that significant gains in the value of the vessel result when design changes are taken into account.

Designing Resilience into Service Supply Chains: A Conceptual Methodology

This chapter presents a methodology for designing resilient service supply chains. The approach combines system design methods with methods from risk assessment. Service supply chains consist of multiple assets, cooperating to fulfill an operation. Each asset has functionality to perform a set of tasks in the operation, and the combined functionalities of the fleet of assets must cover the activities the service supply chain are to perform. When a module in one asset in the fleet experiences loss of functionality, it constitutes a disruption in the service supply chain, a failure mode. The objective of the proposed methodology is to give decision support reducing the vulnerabilities of the service supply chain through design actions that can increase overall service supply chain resilience. The methodology consists of four steps. The first step includes breakdown of operation and service supply chain, mapping of modules to tasks, and selection of service supply chain configuration based on costs and utility. In the second step, failure modes are identified and their criticality assessed. In the third step, we propose design changes to reduce the impact of disruptions. These are evaluated in Step 4, where decisions regarding redesign are made. The recommendations from this methodology can be used to plan for how to redesign in the case of contingencies, or be used as part of an iterative process where the new information is incorporated in the evaluation of initial service supply chain design.

Study of electrical and thermal conduction mechanisms in novel isotropic conductive adhesive

Electrical and thermal contact mechanisms in isotropic conductive adhesive (ICA) based on silver coated polymer particles has been investigated. The adhesive conductivities similar of that of traditional silver filled adhesives at less than 10 % of the silver consumption. The high conductivity has been explained by the development of fused metal-metal contacts between neighboring particles.