IEEE TRANSACTIONS ON SYSTEMS, MAN, AND …

1 IEEE TRANSACTIONS ON SYSTEMS, MAN, AND CYBERNETICS PART C: APPLICATIONS AND REVIEWS, VOL. 42, NO. 1, JANUARY 2012101 model - based Systems engineering : An EmergingApproach for Modern SystemsAna Lu sa Ramos, Member, IEEE,Jos e Vasconcelos Ferreira, and Jaume Barcel oAbstract To engineer the modern large, complex, interdisci-plinary systems-of-systems (SoS), the collaborative world teamsmust speak the same language and must work on the same matter. The matter is the system model and the communi-cation mechanisms must be supported by standard, flexible, andfriendly modeling languages. The evolving model - based systemsengineering (MBSE) approach is leading the way and is expectedto become a standard practice in the field of systems engineering (SE) in the next decade.

2 As an emerging paradigm for the systemsof the 21st century, it seems useful to overview its current stateof the art concerning the developing standards, the embryonic for-malisms, the available modeling languages, the methodologies, andthe major Terms model - based systems engineering (MBSE), mod-eling, SYSTEMSENGINEERING AT AGLANCETHE contemporary world is crowded of large, interdisci-plinary, complex systems made of personnel, hardware,software, information, processes, and facilities. An integratedholistic approach is crucial to develop these systems and takeproper account of their multifaceted nature and numerous in-terrelationships. As the system s complexity and extent grow,the number of parties involved ( , stakeholders and sharehold-ers) usually also raises, thereby bringing a considerable amountof points of view, skills, responsibilities, and interests to field of systems engineering (SE) aims to tackle thecomplex and interdisciplinary whole of those sociotechnicalsystems, thereby providing the means to enable their successfulrealization.

3 Its exploitation in our modern world is assumingan increasing relevance noticeable by emergent standards, sci-entific journals and papers, international conferences, and aca-demic programmes in the field. This significance is probably dueto the escalating complex and hasty nature of our present-daysystems and the interest in achieving their overall maximum Manuscript received June 30, 2010; revised September 13, 2010 andNovember 11, 2010; accepted January 8, 2011. Date of publication March 3,2011; date of current version December 16, 2011. This work was supported inpart by the Portuguese Foundation for Science and Technology under Grant Sis-tema de Formac ao de Recursos Humanos/Bolsas de Doutoramento/43892 paper was recommended by Associate Editor S.

4 H. L. Ramos and J. V. Ferreira are with the Unidade de Investigac aoem Governanc a, Competitividade e Pol ticas P ublicas, Department of Eco-nomics, Management, and Industrial engineering , University of Aveiro, 3810-193 Aveiro, Portugal (e-mail: Barcel o is with the Department of Statistics and Operations Re-search, Technical University of Catalonia, 08034 Barcelona, Spain versions of one or more of the figures in this paper are available onlineat Object Identifier through cooperative, integrative, adaptable, andinteroperable challenge is getting higher as the classical systems areevolving to complex systems-of-systems (SoS))

5 [1], [2], includ-ing both technological and social contexts [3], [4], thereby in-volving a considerable component of customized services withcomplex human-centered aspects [5] and incorporating an ex-tensive set of challenging requirements, like flexibility, sustain-ability, real-time capability, adaptability, expandability, reliabil-ity, usability, and delivery of value to society [6].A. Systems for Systems EngineeringThe SE field can be either classified as an application of thesystems science, and consequently, its perspective is the one ofthe systems thinking One could imagine a science of relation-ships underlying SE [7] and, as a branch of engineering , withrelatively new tradition and characterized by the professionalcreative application of scientific principles to the design and de-velopment of systems.

6 According to Wymore [8], engineering is the creative exploitation of energy, materials and information inorganized systems of men, machine and environment, systemswhich are useful in terms of contemporary human values. The definitions of SE, which began to be formalized in the1970s with the first military standard, are numerous anddiverse; however, they all share the underlying concepts of thesystems approach, like holism, synthesis, interrelationships, aswell as the engineering -project- based ideas of system life cy-cle and requirements. The classical definitions, from the 1970s,are still used, but their focus was mainly on the translation ofrequirements to design.

7 The following ones, from the 1990sand 2000s, are more expanded embracing a more holistic per-spective, the emergent properties, and the sociotechnical definition from the International Council on SE (INCOSE)can be understood as a consensus of the mentioned differentperspectives: An interdisciplinary approach and means to en-able the realization of successful systems. It focuses on definingcustomers needs and required functionality early in the devel-opment cycle, documenting requirements, and then proceedingwith design synthesis and system validation while consideringthe complete problem [9].Surprisingly, in a recent and evolving field, there are alreadyreferences to the old SE (or the traditional, the classical, theordered) and the new SE [6], [7].

8 This evolution has beenreflecting predominantly the nature of the systems to engineer,which, in turn, reflect the tremendous and continuous advancesin the technological and societal classical systems ( , the system -as-machine paradigm)were small to large-scale, multidisciplinary, relatively stable1094-6977/$ 2011 IEEE102 IEEE TRANSACTIONS ON SYSTEMS, MAN, AND CYBERNETICS PART C: APPLICATIONS AND REVIEWS, VOL. 42, NO. 1, JANUARY 2012and predictable, without people as a component, and were typ-ically from the aerospace and defense industries. The new ones( , the system -as-organism paradigm), which must cope withthe global challenges of sustainable development, are largescale, complex, adaptive, interoperable, scalable, technology-intensive, human integrative, and comprise; for example, theso-called super systems, like transportation and sustainableenergy [10].

9 The perspectives of the different shareholders andstakeholders, which may be conflicting and competing, must besynthesized and resolved to serve the highest order system ofinterest needs [6].This emerging metafield of study, in a synergistically coevo-lution with SE and aiming to add a broader context to the field,is called engineering systems, which is a field of study takingan integrative holistic view of large-scale, complex, technolog-ically enabled systems with significant enterprise-level interac-tions and sociotechnical interfaces [6]. There are some otherreferences that label this new field as complex SE [7], engi-neering of complexity [11], or SoS engineering [1], [2].

10 Thetrend is to evolve to a unified SE of the future. According toRouse [12], SE should be an integrative discipline, exploring,understanding, and designing how everything fits Systems- engineering BenchmarksA technical standard is an established norm that allows theunified utilization of criteria, terminology, methods, processes,measures, frameworks, tools, etc. The standards are unifyingreferences necessary to institutionalize the practice of a givendiscipline, helping to translate the technical perspective to amore business one, helping to clarify its relevance to society, andto meet future challenges [13]. Furthermore, and in emergingcollaborative world environments, they facilitate the interoper-ability between people and organizations.