Getting to Grips with
Complexity
D K Hitchins
We often talk about complexity as though it were well
understood. Ask people what makes something complex, however, and
you could get many different answers. So, what is complexity? Is
it a commodity? Can you add some, take some away? From what is it
constituted? How can it be measured? How does it arise? How does
complexity relate to order? Can order arise spontaneously from
complexityor not? Is complexity "good",
"bad", or immaterial? How does complexity relate to
stability and chaos? This paper seeks answers to these questions.
Developments in Systems
Engineering Standards at the DERA
Peter Brook, DRA
The Defence Evaluation and Research Agency (DERA) is committed
to improving the competence of its staff in the field of systems
engineering. Following the successful reception of a prototype
document, a project has been initiated to develop more fully
systems engineering standards to aid in the conduct of the
business. After the first six months of work, there is a clear
appreciation of the target audience for systems engineering
standards, and a reference model is emerging which describes the
relationships between the systems acquisition, systems
engineering and component development processes. These and other
observations arising from the work so far are described.
The Holistic Approach
Benefits of Visualisation in Systems Engineering
C N Smith, British Aerospace Dynamics
Limited
The systems engineering process is continually developing in
response to business and customer drivers and also to take
advantage of new technological opportunities. Synthetic
Environments (SE) allow systems to be demonstrated and visualised
very early in the life cycle, creating exciting new possibilities
for risk reduction and communication. The integration of SE
capabilities into the systems engineering process will be called
the Holistic Approach. This paper provides a cost/ benefit
comparison of the Holistic Approach to the traditional and modern
development approaches.
The Holistic Approach is shown to reduce life cycle costs
through analysis which contrasts the three different approaches
across key activities in the development life cycle, determining
the cost drivers for each approach. Significant risk reduction is
possible through visualisation and early experimentation in the
Holistic Approach The use of an SE capability is not a universal
panacea but must be applied to appropriate activities and tasks,
complementing and aiding more conventional methods. Its place in
a hierarchy of tools and methods can therefore be identified,
with consequential impacts on the development of other tools and
methods in an integrated environment. New possibilities afforded
by the Holistic Approach are discussed, based on the
visualisation capability provided by SE.
A Manifesto for Systems
Engineering
S Mallon, INCOSE UK Chapter Systems
Engineering Practices and Development Committee
In seeking to establish programmes of work within the UK
Chapter it has become clear that without an understanding of the
Principles of Systems Engineering, any such work would be built
on shaky foundations. A Principles Interest Group was therefore
set up to address this need.
The group is still in the early stages of its work, but has
developed an initial view of what is important and essential
about Systems Engineering. The approach taken has been to
identify fundamental issues which can form either the basis for a
test of existing or proposed processes, techniques or tools, or a
point of reference for the development of new capabilities to
fill perceived gaps.
This paper is presented as a 1st public draft, to allow for
comment from a wider group, and in the hope that UK INCOSE
members will want actively to influence and contribute to future
work in this area.
The Uncertainty of
Complexity
P Moore, BSC Consulting Engineers
Complexity and its
Management in Requirements Engineering
A Vickers, University of York
Requirements Engineering is one of the most crucial facets of
any successful project. Errors introduced at the requirements
phase of the life-cycle become increasingly expensive to repair
as development proceeds because of the increasing amounts of
rework that must be undertaken [1]. It is therefore vital to
correctly elicit requirements and to subsequently validate them
with the customer. Requirement specifications should be
consistent, complete, and correct [2]. The problem of performing
such an activity is hard enough in the development of stand alone
software systems, it is countless times harder in the domain of
Systems Engineering where the Requirements Engineer must work
amongst different disciplines with different concepts, methods,
and techniques. The process of negotiation and agreement is that
much harder, and that much more important to get right.
Requirements Engineering is a topic that is rightly recognised
as crucial by both the industrial and academic communities;
however it is the contention of the authors that the two are not
in complete agreement as to the problems that must be solved. The
theme of this Symposium is Getting to Grips with
Complexity, and nowhere is this maxim more applicable than
in Requirements Engineering. In this paper we argue that whilst
both communities agree that complexity is important, each is
concerned with different aspects. This paper outlines the
differences we perceive between the two communities and
identifies the need for a more integrated, and ultimately more
successful, solution to the problems of Requirements Engineering.
It is in the facilitation of such interaction that organisations
such as INCOSE can provide a crucial role. We do not compare and
contrast any techniques in detail in this paper because we
believe 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 summarises
what we believe to be the principal characteristics of industrial
Requirements Engineering. Using this as a foundation, Section 3
lists some of the major problems that such practices suffer.
Section 4, in comparison, highlights the recent direction of
academic Requirements Engineering and provides the basis for
Section 5s discussion of the disparity. Section 6 concludes
the paper.
Beyond the Scientific
Approach The Ecology of Ideas
R Sharp, Roke Manor Research Ltd
Science and Engineering are often viewed as being similar or
closely related. This paper takes a critical look at the
methodology of science and its applicability to engineering. It
concludes that beyond helping to bound possible solutions by
eliminating the impossible, science cannot help in trying to
identify what are good solutions. It is proposed instead that
once scientific knowledge is applied it has no more status that
any other ideas. There may be no methodology applicable to ideas
but there is certainly a process of selection in operation, and
this process has many similarities to the process of natural
selection. In natural selection the driving force for success is
not the process of creation itself, which is simply random, but
rather the process of selection. If this concept is applied to
engineering then it suggests that we have overemphasised the
process of design and neglected the process of selection. The
paper concludes by establishing a model for the ecology of ideas
that shows the contributors and barriers to success. This model
is applied to the processes of engineering to demonstrate how it
might be used to improve our technical capability. The
implications of this concept are far reaching and potentially
very significant but there is a lot to do if it is to survive.
Giving
"top-down" and "bottom-up" their rightful
place
J Boardman, de Montfort University
The subject of this paper is the Company Intranet, and its
main focus is on the need for this relatively recent innovation
to be system engineered. The papers thesis is that the
Company Intranet is capable of enabling radical cultural change
and of delivering extra-ordinary productivity improvement,
provided that it is systems engineered. If it is not to be system
engineered, then it very likely will be vendor-driven. Those
companies who adopt this approach, rather than one based on a
thorough and thoughtful requirements-driven design (of what could
become an essential item of corporate infrastructure), must be
prepared to live with the consequences of that decision.
Task Analysis in Systems
Engineering
Michael Goom, British Aerospace Dynamics Ltd
It is now recognised that the user is part of almost all
systems, and that integrating the human component effectively can
be crucial to total system performance and through life costs.
The development of the Human Factors Integration programme within
the UK has highlighted the key role played by task analysis data
in this integration process. In 1995 a joint Ministry of Defence
and Industry working group organised a two day workshop to
examine if, and how, task analysis could bridge some of the gulfs
between projects, project phases and between the different
disciplines in order to truly integrate the users into the
systems development process. The conclusions were extremely
positive, showing a remarkable degree of agreement across the
many professions represented, and providing a number of
recommendations as to the steps needed to capitalise on this
approach.
Last Updated: 01 August, 2002