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→控制论中的耗散系统 Dissipative systems in control theory
:<math> \dot{V}(x(t)) \le w(u(t),y(t))</math>.<ref>{{cite book |last1=Arcak |first1=Murat |last2=Meissen |first2=Chris |last3=Packard |first3=Andrew |title=Networks of Dissipative Systems |date=2016 |publisher=Springer International Publishing |isbn=978-3-319-29928-0 }}</ref>
:<math> \dot{V}(x(t)) \le w(u(t),y(t))</math>.<ref>{{cite book |last1=Arcak |first1=Murat |last2=Meissen |first2=Chris |last3=Packard |first3=Andrew |title=Networks of Dissipative Systems |date=2016 |publisher=Springer International Publishing |isbn=978-3-319-29928-0 }}</ref>
Willems首先在系统理论[8]中引入耗散性的概念，用输入输出特性来描述动力系统。考虑一个由其状态𝑥（𝑡）、其输入𝑢（𝑡）和其输出𝑡（𝑡）所描述的动力系统，给出了输入输出关系式。如果存在一个连续可微的存储函数𝑉（𝑥（𝑡）），使得𝑉（𝑥（𝑡））≥0且𝑉（𝑥（𝑡））≤𝑢（𝑡），𝑦（𝑡））。
As a special case of dissipativity, a system is said to be passive if the above dissipativity inequality holds with respect to the passivity supply rate <math> w(u(t),y(t)) = u(t)^Ty(t) </math>.
As a special case of dissipativity, a system is said to be passive if the above dissipativity inequality holds with respect to the passivity supply rate <math> w(u(t),y(t)) = u(t)^Ty(t) </math>.
作为耗散性的一个特例，如果上述耗散性不等式对于被动供给率𝑤（𝑢（𝑡），𝑦（𝑡））=𝑢（𝑡）𝑇𝑦（𝑡）成立，则称系统为无源系统。
The physical interpretation is that <math>V(x)</math> is the energy stored in the system, whereas <math>w(u(t),y(t))</math> is the energy that is supplied to the system.
The physical interpretation is that <math>V(x)</math> is the energy stored in the system, whereas <math>w(u(t),y(t))</math> is the energy that is supplied to the system.
物理解释是，𝑉（𝑥）是储存在系统中的能量，而𝑤（𝑢（𝑡））是供给系统的能量。
This notion has a strong connection with [[Lyapunov stability]], where the storage functions may play, under certain conditions of controllability and observability of the dynamical system, the role of Lyapunov functions.
This notion has a strong connection with [[Lyapunov stability]], where the storage functions may play, under certain conditions of controllability and observability of the dynamical system, the role of Lyapunov functions.
这个概念与Lyapunov稳定性有很强的联系，其中存储函数可以在一定的能控性和可观测性条件下发挥Lyapunov函数的作用。
Roughly speaking, dissipativity theory is useful for the design of feedback control laws for linear and nonlinear systems. Dissipative systems theory has been discussed by [[Vasile M. Popov|V.M. Popov]], [[Jan Camiel Willems|J.C. Willems]], D.J. Hill, and P. Moylan. In the case of linear invariant systems{{clarify|reason=Is this the same as a "linear time-invariant system" as in the Wikipedia articles "LTI system theory"?|date=April 2015}}, this is known as positive real transfer functions, and a fundamental tool is the so-called [[Kalman–Yakubovich–Popov lemma]] which relates the state space and the frequency domain properties of positive real systems{{clarify|reason=What is a positive real system?|date=April 2015}}.<ref>{{cite book|url=https://www.springer.com/978-1-84628-892-0|title=Process Control - The Passive Systems Approach| last1=Bao| first1=Jie| last2=Lee| first2=Peter L.| authorlink2=Peter Lee (engineer)| publisher=[[Springer Business+Science Media|Springer-Verlag London]]|year=2007|doi=10.1007/978-1-84628-893-7|isbn=978-1-84628-892-0}}</ref> Dissipative systems are still an active field of research in systems and control, due to their important applications.
Roughly speaking, dissipativity theory is useful for the design of feedback control laws for linear and nonlinear systems. Dissipative systems theory has been discussed by [[Vasile M. Popov|V.M. Popov]], [[Jan Camiel Willems|J.C. Willems]], D.J. Hill, and P. Moylan. In the case of linear invariant systems{{clarify|reason=Is this the same as a "linear time-invariant system" as in the Wikipedia articles "LTI system theory"?|date=April 2015}}, this is known as positive real transfer functions, and a fundamental tool is the so-called [[Kalman–Yakubovich–Popov lemma]] which relates the state space and the frequency domain properties of positive real systems{{clarify|reason=What is a positive real system?|date=April 2015}}.<ref>{{cite book|url=https://www.springer.com/978-1-84628-892-0|title=Process Control - The Passive Systems Approach| last1=Bao| first1=Jie| last2=Lee| first2=Peter L.| authorlink2=Peter Lee (engineer)| publisher=[[Springer Business+Science Media|Springer-Verlag London]]|year=2007|doi=10.1007/978-1-84628-893-7|isbn=978-1-84628-892-0}}</ref> Dissipative systems are still an active field of research in systems and control, due to their important applications.
粗略地说，耗散性理论对于线性系统的设计是有用的。耗散系统理论已经由V.M.Popov、J.C.Willems、D.J.Hill和P.Moylan讨论过。在线性不变系统的情况下，这被称为正实传递函数，一个基本的工具就是所谓的Kalman-Yakubovich-Popov引理，它联系了正实系统的状态空间和频域特性。