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The paper summarizes the challenges and experiences from a course in research methods for systems engineering master’s students. This course is a preparatory course for the final master’s project. Each student selects a topic to investigate in the course. Most of these topics fall into the category of systems of systems engineering. This paper investigates the underlying course contents, teaching method, evaluation, and feedback to/from students. We learnt/noticed that students had challenges in writing the research questions and framing the research design. To overcome these challenges, we demonstrate a systematic procedure by offering a “research framework”.

The key to enable systems integration is that systems inter-communications are accurately and unambiguously specified. In line with ongoing Model-based Systems Engineering (MBSE) initiatives aiming to support systems engineering activities by means of formal and graphical models, we have introduced a logical model for the definition of Interface Communication Modelling Language (ICML), to enable a model-based approach for interface specification. ICML is based on UML and can potentially be integrated with other systems models in similar forms, e.g., SySML, and with systems of systems models in UPDM or related frameworks. We have designed ICML basing on a preliminary domain analysis on radio signal specifications, with application to space systems. In the analysis, we have specifically considered simple digital and unidirectional signals, and subsequently we have included a method to use ICML for Time-Division Multiplexed signals. We also present an excerpt of the ICML metamodel and a simple example application.

International audience; Defense domain is a crucial branch of the government of any country since it ensures the national security and supremacy. Hence, it is imperative thatthe technologies adopted that support their operations must be aligned with the cutting-edge scientific research results and technologies. In particular, software systems play a crucial role in defense domain, since they are usually connected among themselves, forming alliances known as System-of-Systems (SoS). In the last decades, SoS conception has evolved and Brazil has also adopted SoS’ development strategies. However, we identified a lack of reports communicating challenges faced and strategies adopted to carry out SoS Engineering (SoSE) in Brazil. In this direction, this paper reports experience, results, and challenges of a real project carried out in Brazilian Department of Defense, particularly in the Navy’s context. We report the conception of an SoS named Blue Amazon Management System (SisGAAz), a SoS for Brazil’s defense and maritime surveillance. We claim that this report contributes to SoSE since it offers a panorama of SoS conception in Brazil, representing, as a matter of fact, the state of the art in SoSE for Defense in our country, a paramount artifact for the advance of SoS research.

Semantic heterogeneity is a significant challenge to integration in Systems of Systems Engineering (SoSE) due the large variety of languages, domains and tools which are used in their construction. In this paper we envision a strategy for managing this heterogeneity by decomposing domain specific languages into their “building block” theories which can be independently analysed, and used as a basis for linking with similar notations. This provides a systematic approach to building a tool-chain which integrates the different theories, methods and tools used in SoSE. Our approach has been piloted on the development of theories enabling machine-supported analysis of SysML models of SoSs. We conclude that the approach has further potential and identify lines of future research, notably in techniques for handling mixed discrete and continuous behaviour, timebands, mobility and model integration in SoSE.

The term “System of Systems” (SoS) has been used since the 1950s to describe systems that are composed of independent constituent systems, which act jointly towards a common goal through the synergism between them. Examples of SoS arise in areas such as power grid technology, transport, production, and military enterprises. SoS engineering is challenged by the independence, heterogeneity, evolution, and emergence properties found in SoS. This article focuses on the role of model-based techniques within the SoS engineering field. A review of existing attempts to define and classify SoS is used to identify several dimensions that characterise SoS applications. The SoS field is exemplified by a series of representative systems selected from the literature on SoS applications. Within the area of model-based techniques the survey specifically reviews the state of the art for SoS modelling, architectural description, simulation, verification, and testing. Finally, the identified dimensions of SoS characteristics are used to identify research challenges and future research areas of model-based SoS engineering.

The developing discipline of systems of systems engineering (SoSE) is gaining attention in an increasingly broad range of domains; however, each domain comes with its own set of terms and concepts so that there may be confusion between different domains ostensibly engaged in similar challenges. SoSE is faced with concept multiplicity (one term, more than one concept) and term multiplicity (one concept, more than one term). It is unrealistic to expect long-established domains to simply change ontology to match with other domains, but a means of recognising related concepts and terms across domains and across industrial sectors will enable more rapid progress to be made in the development of SoSE. The approach taken to generating a thesaurus, through which such relationships can be documented, is presented. The approach is essentially consultative among SoSE experts and the current version of the thesaurus is available online. A combination of problem statement definition and logical decomposition has been used; the method is described and application is illustrated using well-known terms.

Cyber-physical systems (CPSs) comprise networked computing units that monitor and control physical processes in feedback loops. CPSs have potential to change the ways people and computers interact with the physical world by enabling new ways to control and optimize systems through improved connectivity and computing capabilities. Compared to classical control theory, these systems involve greater unpredictability which may affect the stability and dynamics of the physical subsystems. Further uncertainty is introduced by the dynamic and open computing environments with rapidly changing connections and system configurations. However, due to interactions with the physical world, the dependable operation and tolerance of failures in both cyber and physical components are essential requirements for these systems.The problem of achieving dependable operations for open and networked control systems is approached using a systems engineering process to gain an understanding of the problem domain, since fault tolerance cannot be solved only as a software problem due to the nature of CPSs, which includes close coordination among hardware, software and physical objects. The research methodology consists of developing a concept design, implementing prototypes, and empirically testing the prototypes. Even though modularity has been acknowledged as a key element of fault tolerance, the fault tolerance of highly modular service-oriented architectures (SOAs) has been sparsely researched, especially in distributed real-time systems. This thesis proposes and implements an approach based on using loosely coupled real-time SOA to implement fault tolerance for a teleoperation system.Based on empirical experiments, modularity on a service level can be used to support fault tolerance (i.e., the isolation and recovery of faults). Fault recovery can be achieved for certain categories of faults (i.e., non-deterministic and aging-related) based on loose coupling and diverse operation modes. The proposed architecture also supports the straightforward integration of fault tolerance patterns, such as FAIL-SAFE, HEARTBEAT, ESCALATION and SERVICE MANAGER, which are used in the prototype systems to support dependability requirements. For service failures, systems rely on fail-safe behaviours, diverse modes of operation and fault escalation to backup services. Instead of using time-bounded reconfiguration, services operate in best-effort capabilities, providing resilience for the system. This enables, for example, on-the-fly service changes, smooth recoveries from service failures and adaptations to new computing environments, which are essential requirements for CPSs.The results are combined into a systems engineering approach to dependability, which includes an analysis of the role of safety-critical requirements for control system software architecture design, architectural design, a dependability-case development approach for CPSs and domain-specific fault taxonomies, which support dependability case development and system reliability analyses. Other contributions of this work include three new patterns for fault tolerance in CPSs: DATA-CENTRIC ARCHITECTURE, LET IT CRASH and SERVICE MANAGER. These are presented together with a pattern language that shows how they relate to other patterns available for the domain.

Presentation made by Dr. Warren K. Vaneman, Naval Postgraduate School & Richard Budka, Customer Inspired Solutions, LLC. Provided to: NDIA 15th Annual Systems Engineering Conference Net Centric Operations / Interoperability Track & System of Systems Track.

Special issue on Systems Engineering: Best of France; As the lifetime of many products (that is, goods or services) gets shorter, enterprises have to evolve their information system to account for changes in the internal and external business environment. Indeed, enterprises are using more and more software applications, such as APS, ERP, MES, and SCM, to deal with the increasing complexity of information flows. In this context, a product embedding information about itself and being able to communicate with its environment may be qualified as an “active product.” This new system may then be assimilated to a system-of-systems by gathering all enterprise systems, considered themselves as autonomous systems, together with the active product.