Difference between revisions of "Overview of the Systems Approach"

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===Sub-Theme 5: Transdisciplinarity===
 
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(Martin et al, 2012) “took on the challenge of unifying the languages of “systems praxis” to help practitioners deal with the major cross-discipline, cross-domain problems facing human society in the 21st Century. The [IFSR ‘conversation’ in Linz, April 2012] provided a remarkable opportunity for systems engineers, systems thinkers, and systems scientists to work together to make progress on really difficult issues.”
 
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The group concluded that Systems Praxis (Praxis is a Latin word meaning, roughly, “practice”) is best thought of as “an integrated systems approach putting theories from Systems Science and Systems Thinking into action through technical Systems Engineering and social Systems Intervention”. This requires effective collaboration between different “tribes” with different backgrounds, assumptions, beliefs and value systems. It seems that the best medium for communication across different “tribes” is patterns, and that a common language for “Unified Systems Praxis” could use system patterns and praxis patterns to relate core concepts, principles, and paradigms, allowing stakeholder “silos” to more effectively work together.
 
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This vision was captured in the following figure. A more complex derivative (will) appear(s)  in the final report. The authors say that by using a neutral language and not “boxing in” the domains, they were able to “separate the people from the problem”. The result was a neutral map that each tribe can use to explain its own narrative, worldview, and belief system, as well as to appreciate how the various worldviews and belief systems complement and reinforce each other within systems praxis.
 
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==Synthesis for SEBOK==
 
==Synthesis for SEBOK==
  

Revision as of 19:57, 29 July 2012

This article considers the question, "what is the systems approach and how does it relate to systems engineering (SE)?". This question is discussed in general terms here and expanded upon in the other articles, which detail parts of the approach. The final article in this knowledge area, Applying the Systems Approach, then returns to this question and considers the dynamic aspects of how the approach is used and how this relates in detail to elements of systems engineering.

Definition and Uses of Systems Approach

According to Ryan (2008), the systems approach and SE formed and grew somewhat independently, but are highly related and compatible. Both are based on the concepts of systems thinking that produce a broader understanding of the challenges being faced, the environment, and all of the related parts of the solution. Good SE process and lifecycle descriptions are based upon the systems approach. The best systems engineers must be good systems thinkers and should understand and apply a systems approach to all challenges and problems that they face when conducting SE.

The systems approach is essential when reductionist assumptions (i.e., the whole system has properties derived directly from the properties of their components) no longer apply to the system of interest (SoI). Emergent properties at the system level, which cannot be derived from a summation of the subsystem properties, necessitate a holistic systems approach. The systems approach is often invoked in applications beyond product systems. For example, the systems approach can be used in the educational domain. According to Biggs (1993), the system of interest includes “the student, the classroom, the institution, and the community.” In fact, as the founder of systems thinking and systems science, Ludvig von Bertalanffy (1968), points out, “Systems are everywhere.”

The goal of the systems approach is to understand the organization of ideas and to view problems and solutions holistically. It views the organization of ideas as a compound concept that incorporates structure and behavior of related systems associated with a problem and its possible solutions. It has resulted in a loosely connected set of techniques, where each technique contributes some insight on systemic aspects of problem or solution systems and helps us deal with different aspects of complexity . Because no single technique provides a complete understanding, knowledge of the limits of applicability of individual techniques is central to any systems approach. Most “situation systems” and “respondent systems” (see Figure 1) that systems engineers deal with require a combination of both hard and soft methods. An integration of hard and soft methods is an important aspect of the systems approach.

The following sections address several sub-themes of the “systems approach” in turn.

Sub-theme 1: “Whole system”

Lawson (2010) describes the relationship among the systems approach, systems thinking, and SE as a mindset to “think” and “act” in terms of systems. Developing this mindset is promoted by several paradigms including the system coupling diagram , which includes the elements "situation system", "respondent system", and "system assets" (see Figure 1).

Figure 1. System Coupling Diagram (Lawson 2010) Reprinted with permission of Harold "Bud" Lawson.
  • The situation system is the problem or opportunity situation, either unplanned or planned. The situation may be the work of nature, man-made, a combination of both natural and man-made, or a postulated situation that is to be used as a basis for deeper understanding and training (e.g., business games or military exercises).
  • The respondent system is the system created to respond to the situation. The parallel bars indicate that this system interacts with the situation and transforms the situation into a new situation. Based on the situation that is being treated, a respondent system can have several names, such as project, program, mission, task force, or in a scientific context, experiment. One of the system elements of this system is a control element that directs the operation of the respondent system in its interaction with the situation. This element is based on an instantiation of a control system asset; e.g., a command and control system or a control process of some form.
  • System assets are the sustained assets of one or more enterprises to be used in response to situations. System assets must be adequately managed throughout the life cycle so they will perform their function when instantiated in a respondent system. These assets are the primary objects for systems engineers. Examples of assets include value-added products or services, facilities, instruments and tools, and abstract systems, such as theories, knowledge, processes, and methods.

Lawson's model portrays one aspect of the systems approach and is applicable to understanding a problem; it organizes the resolution of that problem and creates and integrates any relevant assets and capabilities to enable that solution. Since the systems approach is a mindset prerequisite to SE, the premise is that projects and programs executed with this mindset are more likely to solve an identified problem or take advantage of an identified opportunity.

(Martin, 2004) in a classic paper describes seven types of system (“the seven samurai of systems engineering”), and their inter-relationships, all of which system developers need to understand to develop successful systems:

  • the context system (in its original and modified forms),
  • the intervention system,
  • the realization system,
  • the deployed system (the intervention system deployed into the modified context system),
  • collaborating systems,
  • the sustainment system
  • and competing systems.

He contends that all seven systems must be explicitly acknowledged and understood when engineering a solution for a complex adaptive situation.

Sub-theme 2: Whole lifecycle

Ring’s “System Value Cycle” (Ring, 2004) provides a powerful framework for the continuing management and periodic upgrade of long-life and “immortal” systems. It also accurately represents the “continuous” or very rapid product launch and refresh cycle driven by market feedback and constant innovation that we see in most consumer markets (Sillitto, 2005).

Figure 1 . Ellipse Graphic (Ring 1998). © 1998 IEEE. Reprinted, with permission, from Jack Ring, Engineering Value-Seeking Systems, IEEE-SMC Conference Proceedings.

Enterprise and Capability systems engineering can be regarded as running multiple instances of this model concurrently, for different sub-sets of enterprise assets and services, in order to maintain a capability to pursue enterprise goals in a complex and dynamic external environment.

Sub-theme 3: “soft and hard”

“All hard systems exist within soft systems” – that is, all engineered systems are designed to operate with and add value to a containing social and/or ecological system. This diversity of solution elements is captured by frameworks such as STEEPLED (social, technical, economic, environmental, political, legal, ethical and demographic), TEPIDOIL (training, equipment, people, information, doctrine, organization, infrastructure, logistics) and DOTMLPF (Doctrine, Organization, Training, Materiel, Logistics, People, Facilities).

Many authors characterize complex problem situations as “wicked problems” that “cannot be solved but must be managed”. (Sillitto, 2010) describes a complex system lifecycle model in which the decision as to what parts of the problem can be “solved” and what parts must be “managed” is the first key architecting decision, and emphasizes the need for an architectural approach that provides flexibility in the solution to match the level of uncertainty and change in the problem space and stakeholder expectations. It is now normal that “the problem changes over time” and value is determined by the perceptions of key stakeholders, and systems engineering approaches must be congruent with this reality.

Subtheme 4: closed-cycle analysis between nested “layers” of system

(Hitchins, 2007, pp113 ff) describes a nested 5-layer model of systems, each layer characterized by requiring a different approach and skill-set to designing and managing the “system of interest”. Level 1 is “subsystems and technical artefacts”, level 2 is “project systems”, level 3 “business and enterprise systems”, level 4 is “industry systems” and level 5 “societal systems”. Seeking a way of integrating environmental and sustainability considerations into existing system frameworks, (Sillitto and Godfrey) added two additional layers, “ecosystem” and “geosystem”, and showed that with these additional layers the model supports comprehensive closed-cycle analysis of the flow of energy and resources, finished products, services and waste, from natural resources to manufactured products and the consequences of final disposal or recycling.


Synthesis for SEBOK

The systems approach described in the SEBoK uses the following general problem understanding and resolution activities:

  1. identify and understand the relationships between the potential problems and opportunities in a real world situation;
  2. fully understand and describe a selected problem or opportunity in the context of its wider system and its environment;
  3. synthesize viable system solutions to a selected problem or opportunity situation;
  4. analyze and choose between alternative solutions for a given time/cost/quality version of the problem;
  5. provide evidence that a solution has been correctly implemented and integrated; and
  6. deploy, sustain, and use a solution to help solve the problem (or exploit the opportunity).

All of the above are considered within a life cycle framework which may need concurrent, recursive and iterative applications of some or all of the systems approach. Activities 1 and 6 are part of the business cycles of providing stakeholder value (Ring 2004) within an enterprise, whereas activities 2-5 can be mapped directly to product, service, and enterprise engineering life cycles. A distinction is made here between the normal business of an enterprise and the longer-term strategic activities of Enterprise Systems Engineering.


When the systems approach is executed in the real world of an engineered system , a number of engineering and management disciplines emerge, including SE. SEBoK Parts 3 and 4 contain a detailed guide to SE with references to the principles of the systems approach as relevant.

SEBoK Part 5 provides a guide to the relationships between SE and the organizations, and Part 6 provides a guide to the relationship between SE and other disciplines. More detailed discussion of how the systems approach relates to these engineering and management disciplines is included in the Applying the Systems Approach topic in this knowledge area.

References

Works Cited

Biggs, J.B. 1993. "From Theory to Practice: A Cognitive Systems Approach". Journal of Higher Education & Development. Available from http://www.informaworld.com/smpp/content~db=all~content=a758503083.

Boardman, J. and B. Sauser 2008. Systems Thinking - Coping with 21st Century Problems. Boca Raton, FL, USA: CRC Press.

Checkland, P. 1999. Systems Thinking, Systems Practice. New York, NY, USA: John Wiley & Sons.

Edson, R. 2008. Systems Thinking. Applied. A Primer. Arlington, VA, USA: Applied Systems Thinking (ASysT) Institute, Analytic Services Inc.

Lawson, H. 2010. A Journey Through the Systems Landscape. London, UK: College Publications, Kings College.

Senge, P.M. 1990. The Fifth Discipline: The Art and Practice of the Learning Organization. New York, NY, USA: Doubleday/Currency.

Ryan, A. 2008. “What is a Systems Approach?” Journal of Non-linear Science.

Ring J. 2004. "Seeing an Enterprise as a System". INCOSE Insight. 6(2) (January 2004): 7-8.

vonBertalanffy, L. 1968. General Systems Theory. New York, Ny, USA: George Braziller, Inc.

Primary References

Boardman, J. and B. Sauser 2008. Systems Thinking: Coping with 21st Century Problems. Boca Raton, FL, USA: CRC Press.

Checkland, P. 1999. Systems Thinking, Systems Practice. New York, NY, USA: John Wiley & Sons.

Senge, Peter. M. 1990. The Fifth Discipline: The Art and Practice of the Learning Organization. New York: Doubleday/Currency.

Additional References

Biggs, J.B. 1993. "From Theory to Practice: A Cognitive Systems Approach". Journal of Higher Education & Development.. Available from http://www.informaworld.com/smpp/content~db=all~content=a758503083.

Edson, R. 2008. Systems Thinking. Applied. A Primer. Arlington, VA, USA: Applied Systems Thinking (ASysT) Institute, Analytic Services Inc.

Lawson, H. 2010. A Journey Through the Systems Landscape. London, UK: College Publications, Kings College.

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