The xSAP Safety Analysis Platform

This paper describes the xSAP safety analysis platform. xSAP provides several model-based safety analysis features for finite- and infinite-state synchronous transition systems. In particular, it supports library-based definition of fault modes, an automatic model extension facility, generation of safety analysis artifacts such as Dynamic Fault Trees (DFTs) and Failure Mode and Effects Analysis (FMEA) tables. Moreover, it supports probabilistic evaluation of Fault Trees, failure propagation analysis using Timed Failure Propagation Graphs (TFPGs), and Common Cause Analysis (CCA). xSAP has been used in several industrial projects as verification back-end, and is currently being evaluated in a joint R&D Project involving FBK and The Boeing Company

Towards A Model-Based Asset Deterioration Framework Represented by Probabilistic Relational Models

Most asset deterioration tools are designed for a specific application, as a consequence, a small change of the specification may result in a complete change of the tool. Inspired by the model-based approach of separating problem specification from analysis technique, we propose a model-based asset deterioration assessment framework using probabilistic relational models. The probabilistic relational models express abstract probabilistic dependency covers a range of deterioration modelling assumptions. An expert in the domain of asset deterioration can then use his knowledge of the factors that affect deterioration to customise the abstract models to a specific application, without requiring a detailed understanding the underlying computational framework. We illustrate the use of the framework with multiple variants of deterioration models

Preliminary Hazard Analysis Generation Integrated with Operational Architecture - Application to Automobile

Abstract. We are witnessing evolution of standards (as the functional safety one) and increas-ing of complexity. This implies to perform safety studies efficiently and earlier in the context of Model-Based System Engineering. So, in this article, we will propose an evolution of the Pre-liminary Hazard Analysis (PHA) method in order to comply with the overall safety require-ments in the automotive domain. To demonstrate its usefulness, we apply this method to an industrial case which concerns the hazard analysis of unintended acceleration of a vehicle

Model-based dependability analysis : state-of-the-art, challenges and future outlook

Abstract: Over the past two decades, the study of model-based dependability analysis has gathered significant research interest. Different approaches have been developed to automate and address various limitations of classical dependability techniques to contend with the increasing complexity and challenges of modern safety-critical system. Two leading paradigms have emerged, one which constructs predictive system failure models from component failure models compositionally using the topology of the system. The other utilizes design models - typically state automata - to explore system behaviour through fault injection. This paper reviews a number of prominent techniques under these two paradigms, and provides an insight into their working mechanism, applicability, strengths and challenges, as well as recent developments within these fields. We also discuss the emerging trends on integrated approaches and advanced analysis capabilities. Lastly, we outline the future outlook for model-based dependability analysis

Towards a Sustainability Framework for Hydrogen Refuelling Stations: a Risk-based Multidisciplinary Approach

Sustainable hydrogen technology is becoming increasingly important as the world moves towards cleaner and more sustainable sources of energy. Hydrogen is a clean and versatile energy carrier that has the potential to play a critical role in the transition to a low-carbon economy. However, to realize this potential, significant technological advancements are needed in the production, storage, and distribution of hydrogen. To achieve these advancements, a multidisciplinary approach is required that involves technical, organizational, social, and economic factors. Sustainable hydrogen technology development is a complex and multifaceted process that requires the integration of various perspectives and expertise. A framework is needed to bring together these perspectives and develop a common approach to assessing risks and opportunities associated with hydrogen technology. This contribution proposes a framework addressing system modelling and analysis issues in clean hydrogen production and storage, with a focus on uncertainties that can impact social, economic, and environmental sustainability of hydrogen production and refueling facilities. By using risk-based performance and degradation models, the framework helps prevent and mitigate accidents and builds organizational safety culture and procedures while better communicating with the public. The framework also identifies optimal operational modes for increasing the feasibility of hydrogen refueling stations, ultimately leading to the development of more efficient, reliable, and lower-cost hydrogen-based technologies. The development of a common risk-based framework promotes sustainable hydrogen technology and identifies new opportunities for growth and collaboration. The framework is developed collaboratively through an international research network. By integrating multiple perspectives and disciplines, the framework can provide a roadmap for the development of sustainable hydrogen technology and create opportunities for future growth and development in the field

A new methodology for automated Petri Net generation: Method application

A new methodology for automated Petri Net generation: Method applicatio

Performing Safety Analyses with AADL and AltaRica

AADL and AltaRica languages can be used to support the safety assessments of system architectures. These languages were defined with different concerns and this paper aims at presenting their principles and how they can be related. A translator from AADL to AltaRica is proposed and its prototype is applied to a simplified flight control system of a UAV. The resulting AltaRica model has been analyzed with the AltaRica safety tools and the experimental results are discussed

Early validation of satellite COTS-on-board computing systems

International audienceThe competitive market of nano and micro satellites opens perspectives for use of COTS (Com-mercial Off-The-Shelf) electronic components. Current modular electronics design for embedded On-Board Computing systems (OBC) is being challenged by the integration of flexible Systems on Chip (SoC). The deployment of generic avionics and user/payload functionalities on these components is becoming increasingly complex, while Quality of Service must remain compliant with demanding requirements. It is therefore most important to estimate/evaluate those properties as early as possible, regarding a given ap-plication's deployment on a given COTS-based architecture. Model Based System Engineering (MBSE), while a leading practice in architecture description, may still require further study on its use for early evaluation , especially regarding analysis of emerging behaviors and qualitative model-based mapping of ap-plicative functions onto architectural platform. In this paper, we present methods to enhance MBSE design, helping the designer in evaluating candidate mappings and design choices by providing concrete quality measures. We focus on two aspects that were identified as critical in the ATIPPIC IRT project: first, the cost and conflicts in data communications in on-board and peripheral interconnects, which has a bottleneck impact on mapping choices; second, the availability of functions in case of resource failures (from solar radiations), to validate fault-mitigation techniques and estimate the (un)availability of the OBC system. We illustrate the approach on a simplified satellite model, abstracted from a design conceived in the ATIPPIC IRT project

Model-based assessment of energy-efficiency, dependability, and cost-effectiveness of waste heat recovery systems onboard ship

YesTechnological systems are not merely designed with a narrow function in mind. Good designs typically aim at reducing operational costs, e.g. through achieving high energy efficiency and improved dependability (i.e. reliability, availability and maintainability). When there is a choice of alternative design options that perform the same function, it makes sense to compare alternatives so that the variant that minimises operational costs can be selected. In this paper, we examine this issue in the context of the design of Waste Heat Recovery Systems (WHRS) for main engines of large commercial freight vessels. We propose a method that can predict the operational cost of a WHRS via thermodynamic analysis which shows costs related to energy utilisation, and dependability analysis which shows costs related to system unavailability and repair. Our approach builds on recent advances in thermodynamic simulation and compositional dependability analysis techniques. It is a model-based approach, and allows reuse of component libraries, and a high degree of automation which simplify application of the method. Our case study shows that alternative designs can be explored in fast iterations of this method, and that this facilitates the evidence-based selection of a design that minimises operational costs

An overview of fault tree analysis and its application in model based dependability analysis

YesFault Tree Analysis (FTA) is a well-established and well-understood technique, widely used for dependability evaluation of a wide range of systems. Although many extensions of fault trees have been proposed, they suffer from a variety of shortcomings. In particular, even where software tool support exists, these analyses require a lot of manual effort. Over the past two decades, research has focused on simplifying dependability analysis by looking at how we can synthesise dependability information from system models automatically. This has led to the field of model-based dependability analysis (MBDA). Different tools and techniques have been developed as part of MBDA to automate the generation of dependability analysis artefacts such as fault trees. Firstly, this paper reviews the standard fault tree with its limitations. Secondly, different extensions of standard fault trees are reviewed. Thirdly, this paper reviews a number of prominent MBDA techniques where fault trees are used as a means for system dependability analysis and provides an insight into their working mechanism, applicability, strengths and challenges. Finally, the future outlook for MBDA is outlined, which includes the prospect of developing expert and intelligent systems for dependability analysis of complex open systems under the conditions of uncertainty