Getting to Grips withComplexity
D K Hitchins
We often talk about complexity as though it were wellunderstood. Ask people what makes something complex, however, andyou could get many different answers. So, what is complexity? Isit a commodity? Can you add some, take some away? From what is itconstituted? How can it be measured? How does it arise? How doescomplexity relate to order? Can order arise spontaneously fromcomplexity—or not? Is complexity "good","bad", or immaterial? How does complexity relate tostability and chaos? This paper seeks answers to these questions.
Developments in SystemsEngineering Standards at the DERA
Peter Brook, DRA
The Defence Evaluation and Research Agency (DERA) is committedto improving the competence of its staff in the field of systemsengineering. Following the successful reception of a prototypedocument, a project has been initiated to develop more fullysystems engineering standards to aid in the conduct of thebusiness. After the first six months of work, there is a clearappreciation of the target audience for systems engineeringstandards, and a reference model is emerging which describes therelationships between the systems acquisition, systemsengineering and component development processes. These and otherobservations arising from the work so far are described.
The Holistic Approach —Benefits of Visualisation in Systems Engineering
C N Smith, British Aerospace DynamicsLimited
The systems engineering process is continually developing inresponse to business and customer drivers and also to takeadvantage of new technological opportunities. SyntheticEnvironments (SE) allow systems to be demonstrated and visualisedvery early in the life cycle, creating exciting new possibilitiesfor risk reduction and communication. The integration of SEcapabilities into the systems engineering process will be calledthe Holistic Approach. This paper provides a cost/ benefitcomparison of the Holistic Approach to the traditional and moderndevelopment approaches.
The Holistic Approach is shown to reduce life cycle coststhrough analysis which contrasts the three different approachesacross key activities in the development life cycle, determiningthe cost drivers for each approach. Significant risk reduction ispossible through visualisation and early experimentation in theHolistic Approach The use of an SE capability is not a universalpanacea but must be applied to appropriate activities and tasks,complementing and aiding more conventional methods. Its place ina hierarchy of tools and methods can therefore be identified,with consequential impacts on the development of other tools andmethods in an integrated environment. New possibilities affordedby the Holistic Approach are discussed, based on thevisualisation capability provided by SE.
A Manifesto for SystemsEngineering
S Mallon, INCOSE UK Chapter SystemsEngineering Practices and Development Committee
In seeking to establish programmes of work within the UKChapter it has become clear that without an understanding of thePrinciples of Systems Engineering, any such work would be builton shaky foundations. A Principles Interest Group was thereforeset up to address this need.
The group is still in the early stages of its work, but hasdeveloped an initial view of what is important and essentialabout Systems Engineering. The approach taken has been toidentify fundamental issues which can form either the basis for atest of existing or proposed processes, techniques or tools, or apoint of reference for the development of new capabilities tofill perceived gaps.
This paper is presented as a 1st public draft, to allow forcomment from a wider group, and in the hope that UK INCOSEmembers will want actively to influence and contribute to futurework in this area.
P Moore, BSC Consulting Engineers
Complexity and itsManagement in Requirements Engineering
A Vickers, University of York
Requirements Engineering is one of the most crucial facets ofany successful project. Errors introduced at the requirementsphase of the life-cycle become increasingly expensive to repairas development proceeds because of the increasing amounts ofrework that must be undertaken [1]. It is therefore vital tocorrectly elicit requirements and to subsequently validate themwith the customer. Requirement specifications should beconsistent, complete, and correct [2]. The problem of performingsuch an activity is hard enough in the development of stand alonesoftware systems, it is countless times harder in the domain ofSystems Engineering where the Requirements Engineer must workamongst different disciplines with different concepts, methods,and techniques. The process of negotiation and agreement is thatmuch harder, and that much more important to get right.
Requirements Engineering is a topic that is rightly recognisedas crucial by both the industrial and academic communities;however it is the contention of the authors that the two are notin complete agreement as to the problems that must be solved. Thetheme of this Symposium is ‘Getting to Grips withComplexity’, and nowhere is this maxim more applicable thanin Requirements Engineering. In this paper we argue that whilstboth communities agree that complexity is important, each isconcerned with different aspects. This paper outlines thedifferences we perceive between the two communities andidentifies the need for a more integrated, and ultimately moresuccessful, solution to the problems of Requirements Engineering.It is in the facilitation of such interaction that organisationssuch as INCOSE can provide a crucial role. We do not compare andcontrast any techniques in detail in this paper because webelieve the central issue, and main contribution of this paper,is the identification of the nature of the complexity,rather than techniques to deal with specific aspects.
As a starting point to our discussion Section 2 summariseswhat we believe to be the principal characteristics of industrialRequirements Engineering. Using this as a foundation, Section 3lists some of the major problems that such practices suffer.Section 4, in comparison, highlights the recent direction ofacademic Requirements Engineering and provides the basis forSection 5’s discussion of the disparity. Section 6 concludesthe paper.
Beyond the ScientificApproach — The Ecology of Ideas
R Sharp, Roke Manor Research Ltd
Science and Engineering are often viewed as being similar orclosely related. This paper takes a critical look at themethodology of science and its applicability to engineering. Itconcludes that beyond helping to bound possible solutions byeliminating the impossible, science cannot help in trying toidentify what are good solutions. It is proposed instead thatonce scientific knowledge is applied it has no more status thatany other ideas. There may be no methodology applicable to ideasbut there is certainly a process of selection in operation, andthis process has many similarities to the process of naturalselection. In natural selection the driving force for success isnot the process of creation itself, which is simply random, butrather the process of selection. If this concept is applied toengineering then it suggests that we have overemphasised theprocess of design and neglected the process of selection. Thepaper concludes by establishing a model for the ecology of ideasthat shows the contributors and barriers to success. This modelis applied to the processes of engineering to demonstrate how itmight be used to improve our technical capability. Theimplications of this concept are far reaching and potentiallyvery significant but there is a lot to do if it is to survive.
Giving"top-down" and "bottom-up" their rightfulplace
J Boardman, de Montfort University
The subject of this paper is the Company Intranet, and itsmain focus is on the need for this relatively recent innovationto be system engineered. The paper’s thesis is that theCompany Intranet is capable of enabling radical cultural changeand of delivering extra-ordinary productivity improvement,provided that it is systems engineered. If it is not to be systemengineered, then it very likely will be vendor-driven. Thosecompanies who adopt this approach, rather than one based on athorough and thoughtful requirements-driven design (of what couldbecome an essential item of corporate infrastructure), must beprepared to live with the consequences of that decision.
Task Analysis in SystemsEngineering
Michael Goom, British Aerospace Dynamics Ltd
It is now recognised that the user is part of almost allsystems, and that integrating the human component effectively canbe crucial to total system performance and through life costs.The development of the Human Factors Integration programme withinthe UK has highlighted the key role played by task analysis datain this integration process. In 1995 a joint Ministry of Defenceand Industry working group organised a two day workshop toexamine if, and how, task analysis could bridge some of the gulfsbetween projects, project phases and between the differentdisciplines in order to truly integrate the users into thesystems development process. The conclusions were extremelypositive, showing a remarkable degree of agreement across themany professions represented, and providing a number ofrecommendations as to the steps needed to capitalise on thisapproach.
Last Updated: 04 April, 1998