In answering the question How do you model a system? this paper considers therequirements for modelling of a system in the context of the systems developmentlifecycle. It examines the issues that have to be resolved for a systems modelparticularly those related to integration (both horizontal and vertical). A means ofsatisfying the wide ranging requirements of a systems model is proposed. Neither theproposed requirements nor the means of satisfying them are intended as definitive but areanticipated and intended to stimulate further discussion.
Model-based Object Oriented Systems Engineering (MOOSE) is a full lifecycle approach tothe engineering of computer systems, particularly those that require the concurrentdevelopment of software and hardware.
This paper considers some of the motivations for the development of the MOOSE approach;the way that the MOOSE approach is used to support the development of a computer-basedsystem; the role of models in the approach; and the features of the approach’ssupporting tools.
The model described in this paper originated in mid 1993 when the author decided thatit was not possible to explain systems engineering using current & previous twodimensional models. The model has therefore been designed from the outset tobe three dimensional . It has been designed to be immensely decomposable &expandable in regard of processes & products, & within what could be described asa hard framework, to enable the use of Soft Systems Methodology to explore & definethe many in-built processes. As it also includes programme/PERT, the model is described as "unified" in addition to being a generic metamodel.
In the past few years, several models have been developed to measure systemsengineering process maturity. Two of these models have gained a great deal of attention:the INCOSE SECAM and the EPIC (formerly Industrial Collaboration) SE-CMM. This paperdescribes the conduct of a dual systems engineering process assessment that applied bothof these well known models to the same organization using the EPIC SE-CMM AppraisalMethod, rather than the shorter duration INCOSE SECAM Assessment Method. The assessmentwas conducted at Hughes Aircraft Company (HAC), Electro-Optical Systems (EOS). Theassessment is noteworthy since it is the first time both models have been appliedconcurrently. This paper provides a synopsis of both models along with a description ofthe dual assessment. Issues observed from the assessment regarding the models and theAppraisal Method are described; their resolution is important for the conduct of futureassessments. Impacts upon the two models and application methods are discussed based uponthe experiences gained from the dual assessment.
This paper presents a tutorial on a diagramming convention for capturing designrationale. The convention is called the ‘Essential Logic Models’ (ELM). An ELMis used to document the rationale for an emerging design during the Software Engineeringprocess. An ELM tells the ‘story’ of the system and the decisions that were madeduring its construction. The ELM shows the relationship between broad classes ofrequirements and how these relate to the explanatory concepts developed and used duringsystem development. The diagram also shows the important processes that exist within thesystem and the ‘objects’ that the new system will interface to and on which itis dependent.
The presentation covers: what ILS is, why, how and when it is used; it provides anoverview of the LSA process, the main analytic tool used in a ILS programme, one which isused in Systems Engineering (SE); it also includes the relationship between LSA and LCCand other modelling activities; briefly discusses LSA Records (LSAR), some organisationalaspects and lists the principal standards and software sources for the implementation ofLSA and LSAR.
Within this overall purpose, the paper contains three threads:
Obviously, we cannot cover all aspects in a paper of this length, andsome important aspects have had to be left out. Nevertheless, I hope to cover the maintopics.
Two systems engineering capability models have gained a great deal of attention: theINCOSE SECAM and the EPIC SE-CMM. This paper provides a preliminary description of theresults to date of merging the two models and application methods into a single model andassessment method under the auspices of the Electronic Industries Association (EIA). TheEIA Working Group, which is responsible for accomplishing the merger, has representationfrom the EIA, INCOSE, and EPIC. The INCOSE representation is provided by the INCOSEMeasurement Technical Committee. As such, the "merged" products may be regardedas part of the set of measurement products that the INCOSE Measurement Technical Committeeis developing, both internally within INCOSE and jointly with external organizations, tomeasure and improve systems engineering activities. The paper provides a synopsis of thecurrent versions of both models in order to assist in understanding the merging effort andprovide a background to the resulting merged model, designated the EIA Systems EngineeringCapability Model (SECM).
Current state of system science and systems engineering as branches of learning isdiscussed. The meaning of terms: engineering, system and identity is debated leading to ageneric interpretation of engineering and a clarification of what is meant by system. Theconstituents of a situation are described from which the activities of systems engineersas "designers of situations" emerge. Appropriate empirical and theoreticalknowledge rooted in currently available knowledge and required by systems engineers, isoutlined. This should lead to integration of diverse domains through the common theme of"interacting objects" operating in a purposive scheme to produce specificchanges in properties of objects. Activity within a domain of interest and the appropriateknowledge can identify systems engineering as a learned discipline, a part of systemsscience. In addition, the notions of "product" and "situation"engineer are introduced.
Commercial IT systems are generally developed from the perspective of a softwaredevelopment activity, or as the straightforward integration of pre-existing off-the-shelfcomponents. In reality the rapid pace of technological change and the resulting and oftenunexpected interactions between components means that systems may not operate as requiredor as desired. A more rigorous approach based on systems engineering techniques is needed.
This paper aims to investigate the issues surrounding the introduction of systemsengineering disciplines into IT implementation projects. It suggests mechanisms by whichthe principles of systems engineering can be adopted incrementally within an existingorganisation.
This paper describes a framework and underlying concepts for the capture of complexinstrument design requirements based on the needs of the instrument life cycle. However,it is believed that the framework and concepts proposed could be applied to a wider rangeof complex systems. The paper indicates the background to the research which resulted inthe development of the framework, a model of the problem and a methodology for thesolution. Further work is in hand to generate tools and procedures to support the solutionmethodology. The work described is sponsored by the SIRA-UCL Postgraduate TrainingPartnership and forms part of PhD research in the Defence Engineering Group at UniversityCollege London.
The concept of value has been developed for strategic and marketing thinking. Thispaper shows how this concept can be used to understand the relationship between work doneand value delivered to the customer and how this can be applied to the practice of SystemsEngineering. It uses a simple model of Value Space to explore the "leanfrontier" for any market, and the ways in which this frontier can be reached andmoved. Finally it presents the model of value as providing an important insight into theprocess of selection, and therefore a useful perspective for systems engineers wishing tobetter understand how they can satisfy their customers and develop sustainable marketpositions.