Editing Systems theory (section)

==Applications==

===Art===
{{Main|Systems art}}

===Biology===
{{Main|Systems biology}}
Systems biology is a movement that draws on several trends in [[bioscience]] research. Proponents describe systems biology as a biology-based interdisciplinary study field that focuses on complex interactions in [[biological system]]s, claiming that it uses a new perspective ([[holism]] instead of [[reductionist|reduction]]).

Particularly from the year 2000 onwards, the biosciences use the term widely and in a variety of contexts. An often stated ambition of systems biology is the modelling and discovery of [[emergent property|emergent properties]] which represents properties of a system whose theoretical description requires the only possible useful techniques to fall under the remit of systems biology. It is thought that [[Ludwig von Bertalanffy]] may have created the term ''systems biology'' in 1928.<ref name="LVB1928">1928, Kritische Theorie der Formbildung, Borntraeger. In English: Modern Theories of Development: An Introduction to Theoretical Biology, Oxford University Press, New York: Harper, 1933</ref>

Subdisciplines of systems biology include:
* [[Systems neuroscience]]
* [[Systems pharmacology]]

====Ecology====
{{Main|Systems ecology}}
Systems ecology is an [[interdisciplinary]] field of [[ecology]] that takes a [[holism|holistic]] approach to the study of [[ecological systems]], especially [[ecosystem]]s;<ref>Shugart, Herman H., and Robert V. O'Neill. "Systems Ecology". Dowden, Hutchingon & Ross, 1979.</ref><ref>Van Dyne, George M. "Ecosystems, Systems Ecology, and Systems Ecologists". ORNL- 3975. Oak Ridge National Laboratory, Oak Ridge, TN, 1966.</ref><ref>{{cite book|last=Wilkinson|first=David M.|title=Fundamental Processes in Ecology: An Earth Systems Approach|year=2006|publisher=Oxford University Press|isbn=9780198568469|url=https://books.google.com/books?id=PFGWHyRyzBwC&q=Fundamental+Processes+in+Ecology:+An+Earth+Systems+Approach|access-date=2020-11-12|archive-date=2024-04-21|archive-url=https://web.archive.org/web/20240421022110/https://books.google.com/books?id=PFGWHyRyzBwC&q=Fundamental+Processes+in+Ecology:+An+Earth+Systems+Approach|url-status=live}}</ref> it can be seen as an application of general systems theory to ecology.

Central to the systems ecology approach is the idea that an ecosystem is a [[complex system]] exhibiting [[emergent properties]]. Systems ecology focuses on interactions and transactions within and between biological and ecological systems, and is especially concerned with the way the functioning of ecosystems can be influenced by human interventions. It uses and extends concepts from [[thermodynamics]] and develops other macroscopic descriptions of complex systems.

===Chemistry===
{{Main|Systems chemistry}}
Systems chemistry is the science of studying [[Network science|networks]] of interacting molecules, to create new functions from a set (or library) of molecules with different hierarchical levels and emergent properties.<ref>{{cite journal |last1=Ludlow |first1=R. Frederick |last2=Otto |first2=Sijbren |title=Systems chemistry |journal=Chemical Society Reviews |date=2008 |volume=37 |issue=1 |pages=101–108 |doi=10.1039/b611921m |pmid=18197336 }}</ref> Systems chemistry is also related to the origin of life ([[abiogenesis]]).<ref>{{cite journal |last1=von Kiedrowski |first1=Günter |last2=Otto |first2=Sijbren |last3=Herdewijn |first3=Piet |title=Welcome Home, Systems Chemists! |journal=Journal of Systems Chemistry |date=December 2010 |volume=1 |issue=1 |doi=10.1186/1759-2208-1-1 |doi-access=free }}</ref>

===Engineering===
{{Main|Systems engineering}}
Systems engineering is an [[interdisciplinary]] approach and means for enabling the realisation and deployment of successful [[system]]s. It can be viewed as the application of engineering techniques to the engineering of systems, as well as the application of a systems approach to engineering efforts.<ref>{{cite book | last = Thomé | first = Bernhard | date = 1993 | title = Systems Engineering: Principles and Practice of Computer-based Systems Engineering | publisher = John Wiley & Sons | location = Chichester| isbn = 0-471-93552-2}}</ref> Systems engineering integrates other disciplines and specialty groups into a team effort, forming a structured development process that proceeds from concept to production to operation and disposal. Systems engineering considers both the business and the technical needs of all customers, with the goal of providing a quality product that meets the user's needs.<ref>{{cite web|author=INCOSE|author-link=INCOSE|url=http://www.incose.org/practice/whatissystemseng.aspx|title=What is Systems Engineering|access-date=2006-11-26|archive-date=2006-11-28|archive-url=https://web.archive.org/web/20061128033211/http://www.incose.org/practice/whatissystemseng.aspx|url-status=live}}</ref><ref>Blockley, David; Godfrey, Patrick, ''Doing it Differently: Systems for Rethinking Infrastructure (2nd Edition)'' ICE Publishing, London, England, {{ISBN|978-0-7277-6082-1}}.</ref>

====User-centered design process====
Systems thinking is a crucial part of [[user-centered design]] processes and is necessary to understand the whole impact of a new [[human computer interaction]] (HCI) [[Information System|information system]].<ref>{{cite web |last1=Söderström |first1=Jonas |title=Algoritmiska larm belastar sjukvården |url=http://javlaskitsystem.se/2020/02/algoritmiska-larm-belastar-sjukvarden/ |website=Jävla skitsystem |access-date=12 September 2020 |archive-date=6 August 2020 |archive-url=https://web.archive.org/web/20200806011103/http://javlaskitsystem.se/2020/02/algoritmiska-larm-belastar-sjukvarden/ |url-status=live }}</ref> Overlooking this and developing software without insights input from the future users (mediated by user experience designers) is a serious design flaw that can lead to complete failure of information systems, increased stress and mental illness for users of information systems leading to increased costs and a huge waste of resources.<ref>{{cite book |last1=Söderström |first1=Jonas |title=Jävla skitsystem! |date=2010 |publisher=Karnaval Förlag |location=Stockholm |page=16,17}}</ref> It is currently surprisingly uncommon for organizations and governments to investigate the project management decisions leading to serious design flaws and lack of usability.{{citation needed|date=September 2020}}

The [[Institute of Electrical and Electronics Engineers]] estimates that roughly 15% of the estimated $1 trillion used to develop information systems every year is completely wasted and the produced systems are discarded before implementation by entirely preventable mistakes.<ref>{{cite web |last1=Charette |first1=Robert N. |title=Why Software Fails |url=https://spectrum.ieee.org/why-software-fails |website=IEEE Spectrum |date=2 September 2005 |access-date=12 September 2020 |archive-date=9 September 2020 |archive-url=https://web.archive.org/web/20200909063905/https://spectrum.ieee.org/computing/software/why-software-fails |url-status=live }}</ref> According to the CHAOS report published in 2018 by the Standish Group, a vast majority of information systems fail or partly fail according to their survey:
{{Blockquote|Pure success is the combination of high customer satisfaction with high return on value to the organization. Related figures for the year 2017 are: successful: 14%, challenged: 67%, failed 19%.<ref>{{cite web |last1=Portman |first1=Henny |title=Review CHAOS Report 2018 |url=https://hennyportman.wordpress.com/2020/01/03/review-chaos-report-2018/ |website=Henny Portman's Blog |date=3 January 2020 |access-date=11 September 2020 |archive-date=29 September 2020 |archive-url=https://web.archive.org/web/20200929194449/https://hennyportman.wordpress.com/2020/01/03/review-chaos-report-2018/ |url-status=live }}</ref>}}

===Mathematics===
{{Main|System dynamics}}
System dynamics is an approach to understanding the [[nonlinearity|nonlinear]] behaviour of [[complex system]]s over time using [[Stock and flow|stocks, flows]], internal [[feedback loop]]s, and time delays.<ref name="sysdyn">{{Cite web |url=http://web.mit.edu/sysdyn/sd-intro/ |title=MIT System Dynamics in Education Project (SDEP)<!-- Bot generated title --> |access-date=2016-10-28 |archive-date=2019-02-13 |archive-url=https://web.archive.org/web/20190213102210/http://web.mit.edu/sysdyn/sd-intro/ |url-status=live }}</ref>

===Social sciences and humanities===
* [[Systems theory in anthropology]]
* [[Systems theory in archaeology]]
* [[Systems theory in political science]]

====Psychology====
{{Main|Systems psychology}}
Systems psychology is a branch of [[psychology]] that studies [[human behaviour]] and [[experience]] in [[complex system]]s.

It received inspiration from systems theory and systems thinking, as well as the basics of theoretical work from [[Roger Barker]], [[Gregory Bateson]], [[Humberto Maturana]] and others. It makes an approach in [[psychology]] in which groups and individuals receive consideration as [[systems]] in [[homeostasis]]. Systems psychology "includes the domain of [[engineering psychology]], but in addition seems more concerned with societal systems<ref>{{Cite book|title=Dynamical social psychology: Finding order in the flow of human experience|last=Vallacher, R. R., & Nowak, A.|publisher=Guilford Publications|year=2007|location=New York}}</ref> and with the study of motivational, affective, cognitive and group behavior that holds the name engineering psychology."<ref>Lester R. Bittel and Muriel Albers Bittel (1978), ''Encyclopedia of Professional Management'', McGraw-Hill, {{ISBN|0-07-005478-9}}, p. 498.</ref>

In systems psychology, characteristics of [[organizational behaviour]] (such as individual needs, rewards, [[expectation (epistemic)|expectation]]s, and attributes of the people interacting with the [[systems]]) "considers this process in order to create an effective system."<ref>Michael M. Behrmann (1984), ''Handbook of Microcomputers in Special Education''. College Hill Press. {{ISBN|0-933014-35-X}}. p. 212.</ref>

===Informatics===
System theory has been applied in the field of neuroinformatics and connectionist cognitive science. Attempts are being made in neurocognition to merge connectionist cognitive neuroarchitectures with the approach of system theory and [[dynamical systems theory]].<ref>{{cite book |doi=10.1201/9781351043526 |title=Cognitive Science |date=2021 |last1=Maurer |first1=Harald |isbn=978-1-351-04352-6 }} chap. 1.4, 2., 3.26</ref>