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System - Wikipedia, the free encyclopedia
System - Wikipedia, the free encyclopedia: "System
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For other uses, see System (disambiguation).
A schematic representation of a closed system and its boundary
System (from Latin systēma, in turn from Greek σύστημα systēma) is a set of interacting or interdependent entities, real or abstract, forming an integrated whole.
The concept of an 'integrated whole' can also be stated in terms of a system embodying a set of relationships which are differentiated from relationships of the set to other elements, and from relationships between an element of the set and elements not a part of the relational regime.
The scientific research field which is engaged in the study of the general properties of systems include systems theory, systems science and systemics. They investigate the abstract properties of the matter and organization, searching concepts and principles which are independent of the specific domain, substance, type, or temporal scales of existence.
Most systems share the same common characteristics. These common characteristics include the following
* Systems are abstractions of reality.
* Systems have structure which is defined by its parts and their composition.
* Systems have behavior, which involves inputs, processing and outputs of material, information or energy.
* The various parts of a system have functional as well as structural relationships between each other.
The term system may also refer to a set of rules that governs behavior or structure.
Contents
[hide]
* 1 History
* 2 System concepts
* 3 Types of systems
o 3.1 Cultural system
o 3.2 Economic system
* 4 Application of the system concept
o 4.1 Systems in information and computer science
o 4.2 Systems in engineering
o 4.3 Systems in social and cognitive sciences and management research
* 5 See also
* 6 References
* 7 Further reading
* 8 External links
[edit] History
The term System has a long history which can be traced back to the Greek language.
In the 19th century the first to develop the concept of a 'system' in the natural sciences was the French physicist Nicolas Léonard Sadi Carnot who studied thermodynamics. In 1824 he studied what he called the working substance (system), i.e. typically a body of water vapor, in steam engines, in regards to the system's ability to do work when heat is applied to it. The working substance could be put in contact with either a boiler, a cold reservoir (a stream of cold water), or a piston (to which the working body could do work by pushing on it). In 1850, the German physicist Rudolf Clausius generalized this picture to include the concept of the surroundings and began to use the term 'working body' when referring to the system.
One of the pioneers of the general systems theory was the biologist Ludwig von Bertalanffy. In 1945 he introduced models, principles, and laws that apply to generalized systems or their subclasses, irrespective of their particular kind, the nature of their component elements, and the relation or 'forces' between them.[1]
Significant development to the concept of a system was done by Norbert Wiener and Ross Ashby who pioneered the use of mathematics to study systems [2][3] .
In the 1980s the term complex adaptive system was coined at the interdisciplinary Santa Fe Institute by John H. Holland, Murray Gell-Mann and others.
[edit] System concepts
Environment and boundaries
Systems theory views the world as a complex system of interconnected parts. We scope a system by defining its boundary; this means choosing which entities are inside the system and which are outside - part of the environment. We then make simplified representations (models) of the system in order to understand it and to predict or impact its future behavior. These models may define the structure and/or the behaviour of the system.
Natural and man-made systems
There are natural and man-made (designed) systems. Natural systems may not have an apparent objective but their outputs can be interpreted as purposes. Man-made systems are made with purposes that are achieved by the delivery of outputs. Their parts must be related; they must be “designed to work as a coherent entity” - else they would be two or more distinct systems
Open system
An open system usually interacts with some entities in their environment. A closed system is isolated from its environment.
Process and transformation process
A system can also be viewed as a bounded transformation process, that is, a process or collection of processes that transforms inputs into outputs. Inputs are consumed; outputs are produced. The concept of input and output here is very broad. E.g., an output of a passenger ship is the movement of people from departure to destination.
Subsystem
A subsystem is a set of elements, which is a system itself, and a part of a larger system.
[edit] Types of systems
Evidently, there are many types of systems that can be analyzed both quantitatively and qualitatively. For example, with an analysis of urban systems dynamics, [A.W. Steiss] [4] defines five intersecting systems, including the physical subsystem and behavioral system. For sociological models influenced by systems theory, where Kenneth D. Bailey [5] defines systems in terms of conceptual, concrete and abstract systems; either isolated, closed, or open, Walter F. Buckley [6] defines social systems in sociology in terms of mechanical, organic, and process models. Bela H. Banathy [7] cautions that with any inquiry into a system that understanding the type of system is crucial and defines Natural and Designed systems.
In offering these more global definitions, the author maintains that it is important not to confuse one for the other. The theorist explains that natural systems include sub-atomic systems, living systems, the solar system, the galactic system and the Universe. Designed systems are our creations, our physical structures, hybrid systems which include natural and designed systems, and our conceptual knowledge. The human element of organization and activities are emphasized with their relevant abstract systems and representations. A key consideration in making distinctions among various types of systems is to determine how much freedom the system has to select purpose, goals, methods, tools, etc. and how widely is the freedom to select distributed (or concentrated) in the system.
George J. Klir [8] maintains that no 'classification is complete and perfect for all purposes,' and defines systems in terms of abstract, real, and conceptual physical systems, bounded and unbounded systems, discrete to continuous, pulse to hybrid systems, et cetera. The interaction between systems and their environments are categorized in terms of absolutely closed systems, relatively closed, and open systems. The case of an absolutely closed system is a rare, special case. Important distinctions have also been made between hard and soft systems.[9] Hard systems are associated with areas such as systems engineering, operations research and quantitative systems analysis. Soft systems are commonly associated with concepts developed by Peter Checkland through Soft Systems Methodology (SSM) involving methods such as action research and emphasizing participatory designs. Where hard systems might be identified as more 'scientific,' the distinction between them is actually often hard to define.
[edit] Cultural system
Main article: Cultural system
A cultural system may be defined as the interaction of different elements of culture. While a cultural system is quite different from a social system, sometimes both systems together are referred to as the sociocultural system. A major concern in the social sciences is the problem of order. One way that social order has been theorized is according to the degree of integration of cultural and social factors.
[edit] Economic system
Main article: Economic system
An economic system is a mechanism (social institution) which deals with the production, distribution and consumption of goods and services in a particular society. The economic system is composed of people, institutions and their relationships to resources, such as the convention of property. It addresses the problems of economics, like the allocation and scarcity of resources.
[edit] Application of the system concept
Systems modeling is generally a basic principle in engineering and in social sciences. The system is the representation of the entities under concern. Hence inclusion to or exclusion from system context is dependent of the intention of the modeler.
No model of a system will include all features of the real system of concern, and no model of a system must include all entities belonging to a real system of concern.
[edit] Systems in information and computer science
In computer science and information science, system could also be a method or an algorithm. Again, an example will illustrate: There are systems of counting, as with Roman numerals, and various systems for filing papers, or catalogues, and various library systems, of which the Dewey Decimal System is an example. This still fits with the definition of components which are connected together (in this case in order to facilitate the flow of information).
System can also be used referring to a framework, be it software or hardware, designed to allow software programs to run, see platform.
[edit] Systems in engineering
In engineering, the concept of a system is usually well defined. It is used in numerous different concrete contexts, and it is the subject of the basic engineering activities, such as: planning, design, implementation, building, and maintaining. Systems engineering is also a generalized theoretical branch of the different engineering approaches and paradigms.
[edit] Systems in social and cognitive sciences and management research
Social and cognitive sciences recognize systems in human person models and in human societies. They include human brain functions and human mental processes as well as normative ethics systems and social/cultural behavioral patterns.
In management science, operations research and organizational development (OD), human organizations are viewed as systems (conceptual systems) of interacting components such as subsystems or system aggregates, which are carriers of numerous complex processes and organizational structures. Organizational development theorist Peter Senge developed the notion of organizations as systems in his book The Fifth Discipline.
Systems thinking is a style of thinking/reasoning and problem solving. It starts from the recognition of system properties in a given problem. It can be a leadership competency. Some people can think globally while acting locally. Such people consider the potential consequences of their decisions on other parts of larger systems. This is also a basis of systemic coaching in psychology.
Organizational theorists such as Margaret Wheatley have also described the workings of organizational systems in new metaphoric contexts, such as quantum physics, chaos theory, and the self-organization of systems.
[edit] See also
Examples of systems
* List of systems (WPS list)
* Complex system
* Computer system
* Meta-systems
* Solar system
* Systems in human anatomy
Theories about systems
* Chaos theory
* Cybernetics
* Systems ecology
* Systems intelligence
* Systems theory
* Formal system
* World-systems theory
Systems science portal
Related topics
* Complexity and organization
* Network
* Glossary of systems theory
* System of Systems
* System of Systems Engineering
* Systems art
[edit] References
1. ^ 1945, Zu einer allgemeinen Systemlehre, Blätter für deutsche Philosophie, 3/4. (Extract in: Biologia Generalis, 19 (1949), 139-164.
2. ^ 1948, Cybernetics: Or the Control and Communication in the Animal and the Machine. Paris, France: Librairie Hermann & Cie, and Cambridge, MA: MIT Press.Cambridge, MA: MIT Press.
3. ^ 1956. An Introduction to Cybernetics, Chapman & Hall.
4. ^ Steiss 1967, p.8-18.
5. ^ Bailey, 1994.
6. ^ Buckley, 1967.
7. ^ Banathy, 1997.
8. ^ Klir 1969, pp. 69-72
9. ^ Checkland 1997; Flood 1999.
[edit] Further reading
* Alexander Backlund (2000). 'The definition of system'. In: Kybernetes Vol. 29 nr. 4, pp. 444-451.
* Kenneth D. Bailey (1994). Sociology and the New Systems Theory: Toward a Theoretical Synthesis. New York: State of New York Press.
* Bela H. Banathy (1997). 'A Taste of Systemics', ISSS The Primer Project.
* Walter F. Buckley (1967). Sociology and Modern Systems Theory, New Jersey: Englewood Cliffs.
* Peter Checkland (1997). Systems Thinking, Systems Practice. Chichester: John Wiley & Sons, Ltd.
* Robert L. Flood (1999). Rethinking the Fifth Discipline: Learning within the unknowable. London: Routledge.
* George J. Klir (1969). Approach to General Systems Theory, 1969.
[edit] External links
Sister project Look up system in
Wiktionary, the free dictionary.
* Definitions of Systems and Models by Michael Pidwirny, 1999-2007.
* Definitionen von 'System' (1572-2002) by Roland Müller, 2001-2007 (most in German)."
Systems - A Journey Along the Way
Systems - A Journey Along the Way: "Systems
A Journey Along theWay
Welcome to a journey in the realm of systems. The journey is still unfolding as this web site continues to evolve over time. Yet, even with the endless changes, there continues to be a connection, in one fashion or another, with systems. And, I continue to find that the lens which provides a systems perspective is the most revealing of understanding found to date.
The real intent here is not to study systems as a discipline, though more an intent to study lots of things and employ a systems perspective to foster understanding. Agreed, this requires some understanding of systems. As such, information is provided to enable one to develop a level of understanding sufficient to delve into the rest of what resides at this web site.
Every attempt will be made to avoid the major failing of 'system science.' In the words of Ludwig von Bertalanffy, 'The student in 'system science' receives a technical training which makes systems theory -- originally intended to overcome current overspecialization -- into another of the hundreds of academic specialities.'
Enjoy the journey!
System
The word system probably has more varied meanings than any other word in use today. The definition I have become comfortable with I owe to the late Austrian Biologist Ludwig von Bertalanffy.
A system is an entity which maintains its existence
through the mutual interaction of its parts.
The key emphasis here is 'mutual interaction,' in that something is occurring between the parts, over time, which maintains the system. A system is different than a heap or a collection, mostly.
This definition of a system implies something beyond cause and effect. Rather than simply A affects B, there is an implication that B also affects A. Examples of systems are particle, atom, molecule, cell, organ, person, community, state, nation, world, solar system, galaxy, and universe, in increasing levels of complexity. In truth there is only one system, 'the Universe,' and all other systems are really just sub-systems of this larger system. The relevant question has to do with where one chooses to draw boundaries.
Emergence
Associated with the idea of system is a principle called emergence. From the mutual interaction of the parts of a system there arise characteristics which can not be found as characteristic of any of the individual parts.
Stumbling across this as I did was most enlightening. It was probably in high school that I was first acquainted with the idea of synergy; the idea that the whole was greater than the sum of its parts. And, for all the examples ever used, emergence never really hit me until I ran into the right example. The right example just happened to be water! Amazing it took so long since there's so much of it around.
One could study hydrogen and oxygen in isolation from each other forever and never discover the characteristic of wetness. Wetness is an emergent characteristic of the mutual interaction of hydrogen and oxygen when combined to produce the molecular form called water. One has to study the system to get a true understanding of wetness. Studying the parts will not provide an appropriate understanding.
A systems view is somewhat in contradiction to the concept of analysis, which is breaking things down into smaller pieces to simplify the study. Analysis brings with it the risk of potentially loosing the most relevant characteristics of the system, and possibly developing a less than complete understanding. Yes, analysis is an important technique, and at the same time another method of study is also warranted, something I have seen called anasynthis. Anasynthis being the study of the whole, and the parts, in the hopes of developing an appropriate level of understanding.
Classes of Systems
There are multiple ways of characterizing systems. Of those I have come to understand to date, several of the most useful are as follows.
Isolated, Open and Closed Systems
Systems may be characterized as either closed or open. A closed system is one that does not need to interact with its environment to maintain its existence. Examples are atoms and molecules. Mechanical systems are closed systems. Open systems are organic and must interact with their environment in order to maintain their existence. People are open systems in that they must interact with their environment in order to take in food, water, and obtain shelter. People provide waste products to the environment in return.
The examples of the furnace, filling the water glass, adjusting the shower tap are all open systems as there are elements outside the system which are considered to have an effect yet are not elaborated.
An open system may interact with its environment in a growth or balancing fashion. Often the time of influence of the open system on the environment or the environment on the system may be of such lengthy duration or of such minimal nature as to limit its need to be considered. In 1927 Ludwig von Bertalanffy first proposed that the human organism should be treated as an open system.
Any system taken in a large enough context can be considered a closed system. It is often more appropriate to consider a system as a subsystem of some larger system with which it must interact in some way. Taking the larger system into account is unnecessary for understanding the operation of the subsystem. All systems are both subsystems of larger systems and composed of subsystems at the same time.
Boulding's Classification
Economist Kenneth Boulding, one of the founders of The Society for General Systems Theory, in his book, 'The World as a Total System,' defined 5 generalized classes of systems which encompasses all other systems. These provide a means of understanding some general characteristics of systems. These systems are arranged in what is considered an evolutionary hierarchy.
Parasitic System
This is a system in which a positive influence from one element to another provides a negative influence in return to the first element.
I get positive things from you and provide you a negative return in response. Essentially I subsist on you.
Prey/Predator System
In this type of system the elements are essentially dependent on each other from the perspective that the quantity of one element determines the quantity of the other element. The Foxes/Rabbits example is a prey/predator system. Even though the fox may be detrimental to the continuation of an individual rabbit, the fox is instrumental in maintaining the health of the overall rabbit population.
I will feed upon you even though my existence is dependent upon your existence.
Threat System
A threat system is one in which one element doesn't do something if the other element doesn't do something else. The U.S./Soviet Arms Race was a specific example. This particular example lead to escalation since each side said to the other, 'If you start a war I will destroy you.' Yet to continue to validate the threat each side had to continue building arms. It has been said this is a fine example of two countries racing headlong to where neither of them wanted to be.
If you don't do something I don't want you to do then I won't do something you don't want me to do. This may also be formed as, if you do something I want you to do, then I won't do something you don't want me to.
Exchange System
The capitalist economy is a very good example of an exchange system. Elements of the system provide goods and services to other elements in exchange for money or other goods and services.
If you do something I want you to do, then I will do something you want me to do. This may also be stated as, if I do something you want me to do then I expect you will do something I want you to do.
Our buy now pay later economy has a tendency to change an exchange system into a threat system. Initially we purchase something and in exchange we provide a promise, a promise to pay more later. Once we have received what we wanted the system changes and the bank says if you pay your bills then I won't take the stuff away from you, which is essentially a threat systems.
Employer/Employee systems are often transformed from and exchange systems to a threat system. The employee is hired under an exchange premise. I will pay you (what you want) if you do this work (what I want). Once the employee is hired the situation changes and becomes, if you do what I want I won't fire you.
Integrative System
Examples of an integrative system are charitable organizations or business endeavors where individuals ban together to accomplish some common desired objective or goal.
Where you and I do something together because of what we both want to accomplish.
The greatest leverage is found in integrative systems, where all the individuals are motivated by what they are endeavoring to create. This will be addressed in more detail when we get into building shared vision and team learning.
Generative System
During discussions on the Learning Organization list sometime in late 1995 Michael McMaster proposed another category beyond the Integrative System. Michael proposed what he called the Generative System, which might be represented by a situation where two people come together to create something neither of them had any idea of when they began.
Another Classification
At one time I happened across another definition of a systems hierarchy which seemed to make a lot of sense, yet at present I can't recall the reference from whence it came.
Protection System - act when events occur (reactive)
Regulating System - single loop - continuously measure or sample control variables and compare with pre-set desired values and adjust accordingly to regulate control variables (responsive)
Optimizing System - double loop - regulates selected variables in accordance with desired values and also ascertains what the desired values should be to satisfy pre-determined goals (systemic)
Adaptive System - multi-loop/structural - system changes its internal structure in order to optimize its behavior in spite of continuous changes in the environment... (evolutionary)
Introduction to Systems Thinking
theWay of Systems * Feedback * Musings
Copyright © 2004-2005 Gene Bellinger"
A Journey Along theWay
Welcome to a journey in the realm of systems. The journey is still unfolding as this web site continues to evolve over time. Yet, even with the endless changes, there continues to be a connection, in one fashion or another, with systems. And, I continue to find that the lens which provides a systems perspective is the most revealing of understanding found to date.
The real intent here is not to study systems as a discipline, though more an intent to study lots of things and employ a systems perspective to foster understanding. Agreed, this requires some understanding of systems. As such, information is provided to enable one to develop a level of understanding sufficient to delve into the rest of what resides at this web site.
Every attempt will be made to avoid the major failing of 'system science.' In the words of Ludwig von Bertalanffy, 'The student in 'system science' receives a technical training which makes systems theory -- originally intended to overcome current overspecialization -- into another of the hundreds of academic specialities.'
Enjoy the journey!
System
The word system probably has more varied meanings than any other word in use today. The definition I have become comfortable with I owe to the late Austrian Biologist Ludwig von Bertalanffy.
A system is an entity which maintains its existence
through the mutual interaction of its parts.
The key emphasis here is 'mutual interaction,' in that something is occurring between the parts, over time, which maintains the system. A system is different than a heap or a collection, mostly.
This definition of a system implies something beyond cause and effect. Rather than simply A affects B, there is an implication that B also affects A. Examples of systems are particle, atom, molecule, cell, organ, person, community, state, nation, world, solar system, galaxy, and universe, in increasing levels of complexity. In truth there is only one system, 'the Universe,' and all other systems are really just sub-systems of this larger system. The relevant question has to do with where one chooses to draw boundaries.
Emergence
Associated with the idea of system is a principle called emergence. From the mutual interaction of the parts of a system there arise characteristics which can not be found as characteristic of any of the individual parts.
Stumbling across this as I did was most enlightening. It was probably in high school that I was first acquainted with the idea of synergy; the idea that the whole was greater than the sum of its parts. And, for all the examples ever used, emergence never really hit me until I ran into the right example. The right example just happened to be water! Amazing it took so long since there's so much of it around.
One could study hydrogen and oxygen in isolation from each other forever and never discover the characteristic of wetness. Wetness is an emergent characteristic of the mutual interaction of hydrogen and oxygen when combined to produce the molecular form called water. One has to study the system to get a true understanding of wetness. Studying the parts will not provide an appropriate understanding.
A systems view is somewhat in contradiction to the concept of analysis, which is breaking things down into smaller pieces to simplify the study. Analysis brings with it the risk of potentially loosing the most relevant characteristics of the system, and possibly developing a less than complete understanding. Yes, analysis is an important technique, and at the same time another method of study is also warranted, something I have seen called anasynthis. Anasynthis being the study of the whole, and the parts, in the hopes of developing an appropriate level of understanding.
Classes of Systems
There are multiple ways of characterizing systems. Of those I have come to understand to date, several of the most useful are as follows.
Isolated, Open and Closed Systems
Systems may be characterized as either closed or open. A closed system is one that does not need to interact with its environment to maintain its existence. Examples are atoms and molecules. Mechanical systems are closed systems. Open systems are organic and must interact with their environment in order to maintain their existence. People are open systems in that they must interact with their environment in order to take in food, water, and obtain shelter. People provide waste products to the environment in return.
The examples of the furnace, filling the water glass, adjusting the shower tap are all open systems as there are elements outside the system which are considered to have an effect yet are not elaborated.
An open system may interact with its environment in a growth or balancing fashion. Often the time of influence of the open system on the environment or the environment on the system may be of such lengthy duration or of such minimal nature as to limit its need to be considered. In 1927 Ludwig von Bertalanffy first proposed that the human organism should be treated as an open system.
Any system taken in a large enough context can be considered a closed system. It is often more appropriate to consider a system as a subsystem of some larger system with which it must interact in some way. Taking the larger system into account is unnecessary for understanding the operation of the subsystem. All systems are both subsystems of larger systems and composed of subsystems at the same time.
Boulding's Classification
Economist Kenneth Boulding, one of the founders of The Society for General Systems Theory, in his book, 'The World as a Total System,' defined 5 generalized classes of systems which encompasses all other systems. These provide a means of understanding some general characteristics of systems. These systems are arranged in what is considered an evolutionary hierarchy.
Parasitic System
This is a system in which a positive influence from one element to another provides a negative influence in return to the first element.
I get positive things from you and provide you a negative return in response. Essentially I subsist on you.
Prey/Predator System
In this type of system the elements are essentially dependent on each other from the perspective that the quantity of one element determines the quantity of the other element. The Foxes/Rabbits example is a prey/predator system. Even though the fox may be detrimental to the continuation of an individual rabbit, the fox is instrumental in maintaining the health of the overall rabbit population.
I will feed upon you even though my existence is dependent upon your existence.
Threat System
A threat system is one in which one element doesn't do something if the other element doesn't do something else. The U.S./Soviet Arms Race was a specific example. This particular example lead to escalation since each side said to the other, 'If you start a war I will destroy you.' Yet to continue to validate the threat each side had to continue building arms. It has been said this is a fine example of two countries racing headlong to where neither of them wanted to be.
If you don't do something I don't want you to do then I won't do something you don't want me to do. This may also be formed as, if you do something I want you to do, then I won't do something you don't want me to.
Exchange System
The capitalist economy is a very good example of an exchange system. Elements of the system provide goods and services to other elements in exchange for money or other goods and services.
If you do something I want you to do, then I will do something you want me to do. This may also be stated as, if I do something you want me to do then I expect you will do something I want you to do.
Our buy now pay later economy has a tendency to change an exchange system into a threat system. Initially we purchase something and in exchange we provide a promise, a promise to pay more later. Once we have received what we wanted the system changes and the bank says if you pay your bills then I won't take the stuff away from you, which is essentially a threat systems.
Employer/Employee systems are often transformed from and exchange systems to a threat system. The employee is hired under an exchange premise. I will pay you (what you want) if you do this work (what I want). Once the employee is hired the situation changes and becomes, if you do what I want I won't fire you.
Integrative System
Examples of an integrative system are charitable organizations or business endeavors where individuals ban together to accomplish some common desired objective or goal.
Where you and I do something together because of what we both want to accomplish.
The greatest leverage is found in integrative systems, where all the individuals are motivated by what they are endeavoring to create. This will be addressed in more detail when we get into building shared vision and team learning.
Generative System
During discussions on the Learning Organization list sometime in late 1995 Michael McMaster proposed another category beyond the Integrative System. Michael proposed what he called the Generative System, which might be represented by a situation where two people come together to create something neither of them had any idea of when they began.
Another Classification
At one time I happened across another definition of a systems hierarchy which seemed to make a lot of sense, yet at present I can't recall the reference from whence it came.
Protection System - act when events occur (reactive)
Regulating System - single loop - continuously measure or sample control variables and compare with pre-set desired values and adjust accordingly to regulate control variables (responsive)
Optimizing System - double loop - regulates selected variables in accordance with desired values and also ascertains what the desired values should be to satisfy pre-determined goals (systemic)
Adaptive System - multi-loop/structural - system changes its internal structure in order to optimize its behavior in spite of continuous changes in the environment... (evolutionary)
Introduction to Systems Thinking
theWay of Systems * Feedback * Musings
Copyright © 2004-2005 Gene Bellinger"
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