Marine Autonomous Surface Ships (MASS) are tested in public waters. A requirement for MASS to be operated is that they should be at least as safe as conventional ships. Hence, this paper investigates how far the current ship risk models for ship-ship collision, ship-structure collision, and groundings are applicable for risk assessment of MASS. Nine criteria derived from a systems engineering approach are used to assess relevant ship risk models. These criteria aim at assessing relevant considerations for the operation of MASS, such as technical reliability, software performance, human-machine interfaces, operating, and several aspects of communication. From 64 assessed models, published since 2005, ten fulfilled six or more of these criteria. These models were investigated more closely. None of them are suitable to be directly used for risk assessment of MASS. However, they can be used as basis for developing relevant risk models for MASS, which especially need to consider the aspects of software and control algorithms and human-machine interaction.
No abstract is provided for this article.
Path planning is an essential part of autonomous surface vessel (ASV) operations. Risk models can be used to give estimates of risk related to the operation of technical systems, such as ASVs. Combining risk models directly with control systems can be a way to make autonomous systems more capable of assessing and evaluating risk, and in this way allow them to make better decisions. Focusing on path planning, this study aims at investigating how an online risk model used to inform an ASV of risk compares to a static safety domain. The results show that the paths selected when using the risk model can consider different environmental conditions, and the choice of path can be adapted based on how conservative the ASV should be with respect to risk. In this way the risk model provides a more detailed basis for making decisions than the static safety domain.
No abstract is provided for this article.
Autonomous systems may lead to smarter and more efficient operations, but emerging risks are involved, because of lack of knowledge and operational experience with such systems, and challenges related to verification of safe performance. The objective of this paper is to clarify, categorize, and classify risk related to autonomous marine systems, and establish a foundation for risk management of such systems. Autonomous systems are usually associated with unmanned systems, but several manned systems, e.g., offshore oil and gas rigs and ships with complex automation and dynamic positioning (DP) systems, have certain control functionality that may be characterized as autonomous. Therefore, this paper addresses both manned and unmanned systems with different levels of autonomy. This means that the concept of autonomy in this paper includes a range of systems and operations with increasing complexity and major hazard potential, even though autonomous ships are used to exemplify. Hence, the paper addresses a broader approach in contrast to the traditional focus on robotics.
This book offers decision support tools to help operators to make better decisions and methodologies to improve the safety of automated maritime system
The Norwegian Atlantic salmon farming industry is exploring the possibility to run fish farms in more exposed locations. The severe wave and current conditions, irregular wind, sheer remoteness, and limited weather window challenge the operational planning to avoid accidents. The objective of this paper is to present results from applying a generic list of safety-critical parameters to a net cleaning operation to assess their usefulness and relevance in aquaculture. The list was proposed based on implications from major accident causation theories in safety research. The case study demonstrated that the list is a useful operational planning tool to identify activity failure mechanisms that have potential to cause accidents. The results also have implications to how to use barrier principles in aquaculture in general.
This article addresses the present status of seafood-oriented environmental methods and analyses, and pinpoints areas for further development. A recent study of the CO2 emissions associated with the production of farmed salmon in Norway, following the life cycle from hatching to consumption, is presented. The study was initiated due to the increased focus on environmental impacts from food production among consumer organizations, retailers, and authorities. In general, several methods are being currently applied to measure environmental performance. Unfortunately, different methods provide quite different results. An additional challenge is that most of these methods were originally developed for land-based production. If assumptions about the performance of the seafood industry are established on the basis of incorrect information, consequences for both the management and the market level may not be desirable.
No abstract is provided for this article.
No abstract is provided for this article.
This chapter presents methods for analysing interdependencies in critical infrastructures. In general, there are three groups of methods for analysing interdependencies; (1) conceptual, (2) model and simulation and (3) empirical and knowledge-based approaches. Examples of methods belonging to these groups are presented. The latter part of the chapter discusses challenges related to modelling, focusing on how to deal with complexity, trade-offs between abstraction and fidelity, choice of consequence measures and obtaining information.
No abstract is provided for this article.
Reducing the operation and maintenance (O&M) cost is a necessity in current offshore wind farms so that the produced power can achieve a competitive price in the market. An offshore wind farm normally comprises a large number of turbines which demand frequent maintenance visits. In addition to making maintenance plans that avoid downtime and production losses, it is important to utilize the expensive resources, such as service vessels, in an efficient way. This article introduces the routing and scheduling problem of a maintenance fleet for offshore wind farms (RSPMFOWF), which is to determine the optimal assignments of turbines and routes to the vessels in terms of cost. Simultaneously considering the characteristics and limitations in this problem, we present the mathematical formulations for the RSPMFOWF. A computational case study is also carried out. The results provide both the optimized cost and detailed arrangements, which can be directly used in maintenance planning.
his is an Accepted Manuscript of an article published by Taylor & Francis Group in Safety and Reliability of Complex Engineered Systems – Podofi llini et al. (Eds) September 3, 2015 by CRC Press, available online:http://www.crcnetbase.com/doi/pdf/10.1201/b19094-480
This chapter presents the challengesChallenges that complex systemsComplex systems face related to riskRisk modeling and human and organizational factorsOrganizational factors, hardware, and software interactionsInteractions. In Sect. 4.2, risk assessmentRisk assessment of software in automated systems is discussed. A conceptual modelModel to evaluate software failuresFailure is proposed, and challengesChallenges regarding quantification and cybersecurity are presented. In Sect. 4.3, risk assessmentRisk assessment of human factorsHuman factor in automated and autonomousAutonomous systems is discussed. Finally, in Sect. 4.4, a general framework is proposed that considers software and human factorsHuman factor along with hardware elements to perform risk assessmentRisk assessment of complex systemsComplex systems. The framework clarifies how the interactionsInteractions between software, human, and hardware could be considered in risk analysisRisk analysis of complex systemsComplex systems.
