Systems Integration

Systems integration is still an unresolved issue!

Using Models to Assure Emergent Behaviors in Railway Transportation Networks

Abstract

Railway transportation networks are complex systems of systems which exhibit emerging behaviors. Emergence is the property that distinguishes a collection of things from a system which provides a behavior not attainable by any subset of system constituents. At the railway network level, the necessity of proving the desired emerging behaviors, revealing undesired patterns of behavior, and providing evidence that the rate of occurrence of a particular undesired one is below a specific threshold is stated in the RAMS standard. This short paper briefly discusses different aspects of this approach and elaborates on a successful example.

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Review: Rasmussen’s 1997 paper – Risk management in a dynamic society: A modeling problem

The article by Rasmussen (1997) begins with an introduction that risk management is treated differently across all relevant hierarchical levels of a socio-technical system. However, due to the dynamics of the system, treating risk-related decision-making in isolation does not enable us to recognize when we cross the boundary of safe operation. Thus, when assessing risks in a complex socio-technical system, we have to include the layers of legislation, management, work planners and system operators. As a result, we need to touch upon risk models of the disciplines varying from economics, organizational theories and cognitive psychology to engineering.

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A review of ISO/IEC/IEEE/DIS 21840 Systems and software engineering – Guidelines for the utilization of ISO/IEC/IEEE 15288 in the context of System of Systems (SoS) engineering

This post reviews ISO/IEC/IEEE/DIS 21840 Systems and software engineering – Guidelines for the utilization of ISO/IEC/IEEE 15288 (NEN-ISO/IEC/IEEE 15288, 2015) in the context of System of Systems (SoS) engineering. A draft of this document is circulated for comments and approval. The document is therefore yet subject to change and might not yet be referred to as an international standard until published as such[1]. While (NEN-ISO/IEC/IEEE 15288, 2015) applies to systems (including constituent systems), this document provides guidance on the application of these processes to SoS. The scope of the (draft) standard is the same as (NEN-ISO/IEC/IEEE 15288, 2015), which establishes a common framework of process descriptions for describing the life cycle of systems created by humans.  It defines a set of processes and associated terminology from an engineering viewpoint.  These processes can be applied at any level in the hierarchy of a system’s structure.  Selected sets of these processes can be applied throughout the life cycle for managing and performing the stages of a system’s life cycle.  This is accomplished through the involvement of all stakeholders, with the ultimate goal of achieving customer satisfaction, hence addresses more than system engineering activities. In addition it explores the similarities and differences between systems and SoS and, by extension, the similarities and differences between engineering of systems and SoS.

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