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| − | 此词条暂由彩云小译翻译，未经人工整理和审校，带来阅读不便，请见谅。{{More footnotes|date=April 2009}}
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| − | A '''dissipative system''' is a thermodynamically [[open system (systems theory)|open system]] which is operating out of, and often far from, [[thermodynamic equilibrium]] in an environment with which it exchanges [[energy]] and [[matter]]. A tornado may be thought of as a dissipative system.
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| − | A dissipative system is a thermodynamically open system which is operating out of, and often far from, thermodynamic equilibrium in an environment with which it exchanges energy and matter. A tornado may be thought of as a dissipative system.
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| | '''耗散系统 Dissipative system''' 是一种远离热力学平衡的热力学开放系统，运行在与之交换能量和物质的环境中。例如，龙卷风可以被认为是一个耗散系统。 | | '''耗散系统 Dissipative system''' 是一种远离热力学平衡的热力学开放系统，运行在与之交换能量和物质的环境中。例如，龙卷风可以被认为是一个耗散系统。 |
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| − | A '''dissipative structure''' is a dissipative system that has a dynamical régime that is in some sense in a reproducible [[steady state]]. This reproducible steady state may be reached by natural evolution of the system, by artifice, or by a combination of these two.
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| − | A dissipative structure is a dissipative system that has a dynamical régime that is in some sense in a reproducible steady state. This reproducible steady state may be reached by natural evolution of the system, by artifice, or by a combination of these two.
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| | '''耗散结构 Sissipative Structure'''是一种耗散系统，其'''<font color="#ff8000"> 动力学性质dynamical régime</font>'''在某种意义上是一种可重复的稳定状态。可以通过系统的自然进化、使用技巧来进化或两者的结合来达到这种可重复的稳定状态。 | | '''耗散结构 Sissipative Structure'''是一种耗散系统，其'''<font color="#ff8000"> 动力学性质dynamical régime</font>'''在某种意义上是一种可重复的稳定状态。可以通过系统的自然进化、使用技巧来进化或两者的结合来达到这种可重复的稳定状态。 |
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| − | | + | == 概览 == |
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| − | == 概览 Overview == | |
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| − | A [[Dissipation|dissipative]] structure is characterized by the spontaneous appearance of symmetry breaking ([[anisotropy]]) and the formation of complex, sometimes [[Chaos theory|chaotic]], structures where interacting particles exhibit long range correlations. Examples in everyday life include [[convection]], [[turbulence|turbulent flow]], [[cyclone]]s, [[Tropical cyclone|hurricane]]s and [[life|living organisms]]. Less common examples include [[laser]]s, [[Bénard cells]], [[droplet cluster]], and the [[Belousov–Zhabotinsky reaction]].<ref>{{cite journal|last1=Li|first1=HP|title=Dissipative Belousov–Zhabotinsky reaction in unstable micropyretic synthesis|journal=Current Opinion in Chemical Engineering|date=February 2014|volume=3|pages=1–6|doi=10.1016/j.coche.2013.08.007}}</ref>
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| − | A dissipative structure is characterized by the spontaneous appearance of symmetry breaking (anisotropy) and the formation of complex, sometimes chaotic, structures where interacting particles exhibit long range correlations. Examples in everyday life include convection, turbulent flow, cyclones, hurricanes and living organisms. Less common examples include lasers, Bénard cells, droplet cluster, and the Belousov–Zhabotinsky reaction.
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| | 耗散结构的特点是自发出现对称性破坏（各向异性）和形成复杂的、有时是混沌的结构，在这些结构中，相互作用的粒子展现出长程关联的性质。日常生活中的例子包括对流、湍流、旋风、飓风和生物体。较少见的例子包括激光、 '''<font color="#ff8000">b 细胞Bénard cells</font>'''、'''<font color="#ff8000">液滴簇droplet cluster</font>'''和'''<font color="#ff8000">BZ反应Belousov–Zhabotinsky reaction</font>'''。 | | 耗散结构的特点是自发出现对称性破坏（各向异性）和形成复杂的、有时是混沌的结构，在这些结构中，相互作用的粒子展现出长程关联的性质。日常生活中的例子包括对流、湍流、旋风、飓风和生物体。较少见的例子包括激光、 '''<font color="#ff8000">b 细胞Bénard cells</font>'''、'''<font color="#ff8000">液滴簇droplet cluster</font>'''和'''<font color="#ff8000">BZ反应Belousov–Zhabotinsky reaction</font>'''。 |
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| − | One way of mathematically modeling a dissipative system is given in the article on ''[[wandering set]]s'': it involves the action of a [[group (mathematics)|group]] on a [[measure (mathematics)|measurable set]].
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| − | One way of mathematically modeling a dissipative system is given in the article on wandering sets: it involves the action of a group on a measurable set.
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| | 在关于'''<font color="#ff8000">游荡集合 Wandering Sets</font>'''的文章中给出了一种对耗散系统进行数学建模的方法：这种方法涉及到一个可测集上的群的作用。 | | 在关于'''<font color="#ff8000">游荡集合 Wandering Sets</font>'''的文章中给出了一种对耗散系统进行数学建模的方法：这种方法涉及到一个可测集上的群的作用。 |
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| | + | 耗散系统也可以作为研究经济系统和复杂系统的工具。<ref>{{Cite book|title = The Unity of Science and Economics: A New Foundation of Economic Theory|last = Chen|first = Jing|publisher = Springer|year = 2015|isbn = |location = https://www.springer.com/us/book/9781493934645|pages = }}</ref>例如，一个包含纳米线自组装的耗散系统被用作理解熵产生和生物系统鲁棒性之间关系的模型。<ref>{{cite journal|last1=Hubler|first1=Alfred|last2=Belkin|first2=Andrey|last3=Bezryadin|first3=Alexey|title=Noise induced phase transition between maximum entropy production structures and minimum entropy production structures?|journal=Complexity|date=2 January 2015|volume=20|issue=3|pages=8–11|doi=10.1002/cplx.21639|bibcode=2015Cmplx..20c...8H}}</ref> |
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| − | Dissipative systems can also be used as a tool to study economic systems and [[complex systems]].<ref>{{Cite book|title = The Unity of Science and Economics: A New Foundation of Economic Theory|last = Chen|first = Jing|publisher = Springer|year = 2015|isbn = |location = https://www.springer.com/us/book/9781493934645|pages = }}</ref> For example, a dissipative system involving [[self-assembly]] of nanowires has been used as a model to understand the relationship between entropy generation and the robustness of biological systems.<ref>{{cite journal|last1=Hubler|first1=Alfred|last2=Belkin|first2=Andrey|last3=Bezryadin|first3=Alexey|title=Noise induced phase transition between maximum entropy production structures and minimum entropy production structures?|journal=Complexity|date=2 January 2015|volume=20|issue=3|pages=8–11|doi=10.1002/cplx.21639|bibcode=2015Cmplx..20c...8H}}</ref>
| + | == 热力学中的耗散结构 == |
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| − | Dissipative systems can also be used as a tool to study economic systems and complex systems. For example, a dissipative system involving self-assembly of nanowires has been used as a model to understand the relationship between entropy generation and the robustness of biological systems.
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| − | 耗散系统也可以作为研究经济系统和复杂系统的工具。例如，一个包含纳米线自组装的耗散系统被用作理解熵产生和生物系统鲁棒性之间关系的模型。
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| − | == 热力学中的耗散结构 Dissipative structures in thermodynamics == | |
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| − | The term ''dissipative structure'' was coined by Russian-Belgian physical chemist [[Ilya Prigogine]], who was awarded the [[Nobel Prize in Chemistry]] in 1977 for his pioneering work on these structures. The dissipative structures considered by Prigogine have dynamical regimes that can be regarded as thermodynamic steady states, and sometimes at least can be described by suitable [[extremal principles in non-equilibrium thermodynamics]].
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| − | The term dissipative structure was coined by Russian-Belgian physical chemist Ilya Prigogine, who was awarded the Nobel Prize in Chemistry in 1977 for his pioneering work on these structures. The dissipative structures considered by Prigogine have dynamical regimes that can be regarded as thermodynamic steady states, and sometimes at least can be described by suitable extremal principles in non-equilibrium thermodynamics.
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| − | 耗散结构一词是由俄罗斯-比利时的物理化学家''伊利亚·普里高津 Ilya Prigogine''发明的，他因在耗散结构方面的开创性工作获得了1977年的诺贝尔化学奖。普里高津Prigogine所考虑的耗散结构具有可被视为热力学稳态的'''<font color="#ff8000">动力学性质dynamical regimes</font>'''，有时至少可以用合适的非平衡态热力学中的极值定理来描述。
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| | + | 耗散结构一词是由俄罗斯-比利时的物理化学家[[伊利亚·普里高津 Ilya Prigogine]]发明的，他因在耗散结构方面的开创性工作获得了1977年的诺贝尔化学奖。普里高津Prigogine所考虑的耗散结构具有可被视为热力学稳态的'''<font color="#ff8000">动力学性质dynamical regimes</font>'''，有时至少可以用合适的非平衡态热力学中的极值定理来描述。 |
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| | + | 在他的诺贝尔演讲中，<ref name="PrigogineNobel">{{cite journal|last1=Prigogine|first1=Ilya|title=Time, Structure and Fluctuations|url=https://www.nobelprize.org/nobel_prizes/chemistry/laureates/1977/prigogine-lecture.html|website=Nobelprize.org|pmid=17738519}}</ref>Prigogine解释了远离平衡的热力学系统如何与接近平衡的系统有着截然不同的行为。在平衡点附近，采用局部平衡假设，并可局部定义自由能和熵等典型热力学量。我们可以假定系统的（广义）通量和力之间是线性关系。线性热力学的两个著名成果是'''<font color="#ff8000">昂萨格倒易关系 Onsager reciprocal relations</font>'''和'''<font color="#ff8000">最小熵产生定理 the principle of minimum entropy production</font>'''。<ref>{{cite journal|last1=Prigogine|first1=Ilya|title=Modération et transformations irréversibles des systèmes ouverts|journal=Bulletin de la Classe des Sciences, Académie Royale de Belgique|date=1945|volume=31|pages=600–606}}</ref> 在努力将这些结果推广到远离平衡的系统之后，人们发现它们在这个系统中不成立，并且得到了相反的结果。 |
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| | + | 严格分析此类系统的一种方法是研究远离平衡的系统的稳定性。接近平衡点时，我们可以证明存在[[<font color="#ff8000">李亚普诺夫函数 Lyapunov function</font>]]，它确保熵趋于稳定的最大值。波动在固定点附近被阻尼，宏观描述就已足够。然而，远离平衡的稳定性不再是一个普遍的性质，并且可以被打破。在化学系统中，这是在存在自催化反应的情况下发生的，例如在'''<font color="#ff8000">布鲁塞尔模型 Brusselator</font>'''中。如果系统被驱动超过一定的阈值，振荡不再被阻尼，而是可能被放大。从数学上讲，这相当于一个'''<font color="#ff8000">霍普夫分岔 Hopf bifurcation</font>'''，其中一个参数增加超过一定的值会导致'''<font color="#ff8000">极限环行为 limit cycle behavior</font>'''。如果通过反应扩散方程来考虑空间效应，就会产生长程关联和'''<font color="#ff8000">空间有序模式spatially ordered patterns</font>'''，<ref name="LemarchandNicolis">{{cite journal|last1=Lemarchand|first1=H.|last2=Nicolis|first2=G.|title=Long range correlations and the onset of chemical instabilities|journal=Physica|date=1976|volume=82A|issue=4|pages=521–542|doi=10.1016/0378-4371(76)90079-0|bibcode=1976PhyA...82..521L}}</ref>例如'''<font color="#ff8000">BZ反应 Belousov–Zhabotinsky reaction</font>'''。由于不可逆过程而产生的具有这种物质动态状态的系统是耗散结构。 |
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| − | In his Nobel lecture,<ref name="PrigogineNobel">{{cite journal|last1=Prigogine|first1=Ilya|title=Time, Structure and Fluctuations|url=https://www.nobelprize.org/nobel_prizes/chemistry/laureates/1977/prigogine-lecture.html|website=Nobelprize.org|pmid=17738519}}</ref> Prigogine explains how thermodynamic systems far from equilibrium can have drastically different behavior from systems close to equilibrium. Near equilibrium, the ''local equilibrium'' hypothesis applies and typical thermodynamic quantities such as free energy and entropy can be defined locally. One can assume linear relations between the (generalized) flux and forces of the system. Two celebrated results from linear thermodynamics are the [[Onsager reciprocal relations]] and the principle of minimum entropy production.<ref>{{cite journal|last1=Prigogine|first1=Ilya|title=Modération et transformations irréversibles des systèmes ouverts|journal=Bulletin de la Classe des Sciences, Académie Royale de Belgique|date=1945|volume=31|pages=600–606}}</ref> After efforts to extend such results to systems far from equilibrium, it was found that they do not hold in this regime and opposite results were obtained.
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| − | In his Nobel lecture, Prigogine explains how thermodynamic systems far from equilibrium can have drastically different behavior from systems close to equilibrium. Near equilibrium, the local equilibrium hypothesis applies and typical thermodynamic quantities such as free energy and entropy can be defined locally. One can assume linear relations between the (generalized) flux and forces of the system. Two celebrated results from linear thermodynamics are the Onsager reciprocal relations and the principle of minimum entropy production. After efforts to extend such results to systems far from equilibrium, it was found that they do not hold in this regime and opposite results were obtained.
| + | 最近的研究重新考虑了Prigogine的耗散结构观点与生物系统的关系。<ref name="England">{{cite journal|last1=England|first1=Jeremy L.|title=Dissipative adaptation in driven self-assembly|journal=Nature Nanotechnology|date=4 November 2015|volume=10|issue=11|pages=919–923|doi=10.1038/NNANO.2015.250|pmid=26530021|bibcode=2015NatNa..10..919E}}</ref> |
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| − | 在他的诺贝尔演讲中，普里高津Prigogine解释了远离平衡的热力学系统如何与接近平衡的系统有着截然不同的行为。在平衡点附近，采用局部平衡假设，并可局部定义自由能和熵等典型热力学量。我们可以假定系统的（广义）通量和力之间是线性关系。线性热力学的两个著名成果是'''<font color="#ff8000">昂萨格倒易关系Onsager reciprocal relations</font>'''和'''<font color="#ff8000">最小熵产生定理the principle of minimum entropy production</font>'''。在努力将这些结果推广到远离平衡的系统之后，人们发现它们在这个系统中不成立，并且得到了相反的结果。
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| | + | == 控制论中的耗散系统 == |
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| | + | Willems首先在系统理论中引入耗散性的概念，<ref>{{cite journal |last1=Willems |first1=J.C. |title=Dissipative dynamical systems part 1: General theory |journal=Arch. Rational Mech. Anal. |date=1972 |volume=45 |issue=5 |page=321 |doi=10.1007/BF00276493 |bibcode=1972ArRMA..45..321W |hdl=10338.dmlcz/135639 |url=http://dml.cz/bitstream/handle/10338.dmlcz/135639/Kybernetika_41-2005-1_5.pdf }}</ref>用输入输出特性来描述动力系统。考虑一个由其状态<math> x(t) </math>、输入<math>u(t)</math>和输出<math>y(t)</math>所描述的动力系统，输入-输出的相关性被给出了供给率<math> w(u(t),y(t))</math>。如果存在一个连续可微的存储函数<math> V(x(t))</math>，使得 <math>V(0)=0</math>, <math>V(x(t))\ge 0 </math>且<math> \dot{V}(x(t)) \le w(u(t),y(t))</math>.<ref>，则系统对于供给率来说是耗散的。<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> |
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| | + | 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 <math> w(u(t),y(t)) = u(t)^Ty(t) </math>成立，则称系统为无源系统。 |
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| − | One way to rigorously analyze such systems is by studying the stability of the system far from equilibrium. Close to equilibrium, one can show the existence of a [[Lyapunov function]] which ensures that the entropy tends to a stable maximum. Fluctuations are damped in the neighborhood of the fixed point and a macroscopic description suffices. However, far from equilibrium stability is no longer a universal property and can be broken. In chemical systems, this occurs with the presence of [[autocatalytic]] reactions, such as in the example of the [[Brusselator]]. If the system is driven beyond a certain threshold, oscillations are no longer damped out, but may be amplified. Mathematically, this corresponds to a [[Hopf bifurcation]] where increasing one of the parameters beyond a certain value leads to [[limit cycle]] behavior. If spatial effects are taken into account through a [[reaction-diffusion equation]], long-range correlations and spatially ordered patterns arise,<ref name="LemarchandNicolis">{{cite journal|last1=Lemarchand|first1=H.|last2=Nicolis|first2=G.|title=Long range correlations and the onset of chemical instabilities|journal=Physica|date=1976|volume=82A|issue=4|pages=521–542|doi=10.1016/0378-4371(76)90079-0|bibcode=1976PhyA...82..521L}}</ref> such as in the case of the [[Belousov–Zhabotinsky reaction]]. Systems with such dynamic states of matter that arise as the result of irreversible processes are dissipative structures.
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| − | One way to rigorously analyze such systems is by studying the stability of the system far from equilibrium. Close to equilibrium, one can show the existence of a Lyapunov function which ensures that the entropy tends to a stable maximum. Fluctuations are damped in the neighborhood of the fixed point and a macroscopic description suffices. However, far from equilibrium stability is no longer a universal property and can be broken. In chemical systems, this occurs with the presence of autocatalytic reactions, such as in the example of the Brusselator. If the system is driven beyond a certain threshold, oscillations are no longer damped out, but may be amplified. Mathematically, this corresponds to a Hopf bifurcation where increasing one of the parameters beyond a certain value leads to limit cycle behavior. If spatial effects are taken into account through a reaction-diffusion equation, long-range correlations and spatially ordered patterns arise, such as in the case of the Belousov–Zhabotinsky reaction. Systems with such dynamic states of matter that arise as the result of irreversible processes are dissipative structures.
| + | 物理解释是，<math>V(x)</math>是储存在系统中的能量，而<math>w(u(t),y(t))</math>是供给系统的能量。 |
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| − | 严格分析此类系统的一种方法是研究远离平衡的系统的稳定性。接近平衡点时，我们可以证明存在'''<font color="#ff8000">李亚普诺夫函数 Lyapunov function</font>'''，它确保熵趋于稳定的最大值。波动在固定点附近被阻尼，宏观描述就已足够。然而，远离平衡的稳定性不再是一个普遍的性质，并且可以被打破。在化学系统中，这是在存在自催化反应的情况下发生的，例如在'''<font color="#ff8000">布鲁塞尔模型Brusselator</font>'''中。如果系统被驱动超过一定的阈值，振荡不再被阻尼，而是可能被放大。从数学上讲，这相当于一个'''<font color="#ff8000">霍普夫分岔Hopf bifurcation</font>'''，其中一个参数增加超过一定的值会导致'''<font color="#ff8000">极限环行为limit cycle behavior</font>'''。如果通过反应扩散方程来考虑空间效应，就会产生长程关联和'''<font color="#ff8000">空间有序模式spatially ordered patterns</font>'''，例如'''<font color="#ff8000">BZ反应Belousov–Zhabotinsky reaction</font>'''。由于不可逆过程而产生的具有这种物质动态状态的系统是耗散结构。
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| | + | 这个概念与'''<font color="#ff8000"> 李亚普诺夫稳定性 Lyapunov stability</font>'''有很强的联系，其中，在动力系统能控性和可观测性一定的条件下，存储函数可以起到'''<font color="#ff8000"> 李亚普诺夫函数Lyapunov functions</font>'''的作用。 |
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| | + | 粗略地说，耗散理论对于设计线性和非线性系统的反馈控制律是有用的。V.M.Popov、J.C.Willems、D.J.Hill和P.Moylan讨论过耗散系统理论。在线性不变系统中，这被称为'''<font color="#ff8000"> 正实传递函数positive real transfer functions</font>'''，一个基本的工具就是所谓的'''<font color="#ff8000">Kalman-Yakubovich-Popov引理 Kalman–Yakubovich–Popov lemma</font>'''，它关系到正实系统的状态空间和频域特性。<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>由于其重要的应用，耗散系统一直是系统与控制领域的研究热点。 |
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| − | Recent research has seen reconsideration of Prigogine's ideas of dissipative structures in relation to biological systems.<ref name="England">{{cite journal|last1=England|first1=Jeremy L.|title=Dissipative adaptation in driven self-assembly|journal=Nature Nanotechnology|date=4 November 2015|volume=10|issue=11|pages=919–923|doi=10.1038/NNANO.2015.250|pmid=26530021|bibcode=2015NatNa..10..919E}}</ref>
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| − | Recent research has seen reconsideration of Prigogine's ideas of dissipative structures in relation to biological systems.
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| − | 最近的研究重新考虑了普里高津Prigogine的耗散结构观点与生物系统的关系。
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| − | == 控制论中的耗散系统 Dissipative systems in control theory ==
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| − | [[Jan Camiel Willems|Willems]] first introduced the concept of dissipativity in systems theory<ref>{{cite journal |last1=Willems |first1=J.C. |title=Dissipative dynamical systems part 1: General theory |journal=Arch. Rational Mech. Anal. |date=1972 |volume=45 |issue=5 |page=321 |doi=10.1007/BF00276493 |bibcode=1972ArRMA..45..321W |hdl=10338.dmlcz/135639 |url=http://dml.cz/bitstream/handle/10338.dmlcz/135639/Kybernetika_41-2005-1_5.pdf }}</ref> to describe dynamical systems by input-output properties. Considering a dynamical system described by its state <math> x(t) </math>, its input <math>u(t)</math> and its output <math>y(t)</math>, the input-output correlation is given a supply rate <math> w(u(t),y(t))</math>. A system is said to be dissipative with respect to a supply rate if there exists a continuously differentiable storage function <math> V(x(t))</math> such that <math>V(0)=0</math>, <math>V(x(t))\ge 0 </math> and
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| − | :<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>
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| − | Willems first introduced the concept of dissipativity in systems theory to describe dynamical systems by input-output properties. Considering a dynamical system described by its state 𝑥(𝑡), its input 𝑢(𝑡) and its output 𝑦(𝑡), the input-output correlation is given a supply rate 𝑤(𝑢(𝑡),𝑦(𝑡)). A system is said to be dissipative with respect to a supply rate if there exists a continuously differentiable storage function 𝑉(𝑥(𝑡)) such that 𝑉(0)=0, 𝑉(𝑥(𝑡))≥0 and𝑉˙(𝑥(𝑡))≤𝑤(𝑢(𝑡),𝑦(𝑡)).
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| − | Willems首先在系统理论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)、输入𝑢(𝑡)和输出𝑦(𝑡)所描述的动力系统，输入-输出的相关性被给出了供给率𝑤(𝑢(𝑡),𝑦(𝑡))。如果存在一个连续可微的存储函数𝑉(𝑥(𝑡))，使得𝑉(0)=0，𝑉(𝑥(𝑡))≥0且𝑉˙(𝑥(𝑡))≤𝑤(𝑢(𝑡),𝑦(𝑡))，则系统对于供给率来说是耗散的。
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| − | 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>.
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| − | 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 𝑤(𝑢(𝑡),𝑦(𝑡))=𝑢(𝑡)𝑇𝑦(𝑡).
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| − | 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。
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| − | 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.
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| − | The physical interpretation is that 𝑉(𝑥) is the energy stored in the system, whereas 𝑤(𝑢(𝑡),𝑦(𝑡)) is the energy that is supplied to the system.
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| − | 物理解释是，𝑉(𝑥)是储存在系统中的能量，而𝑤(𝑢(𝑡),𝑦(𝑡))是供给系统的能量。
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| − | 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.
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| − | 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.
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| − | 这个概念与'''<font color="#ff8000"> 李亚普诺夫稳定性Lyapunov stability</font>'''有很强的联系，其中，在动力系统能控性和可观测性一定的条件下，存储函数可以起到'''<font color="#ff8000"> 李亚普诺夫函数Lyapunov functions</font>'''的作用。
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| − | 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.
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| − | 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 V.M. Popov, J.C. Willems, D.J. Hill, and P. Moylan. In the case of linear invariant systems模板:Clarify, 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模板:Clarify.[10] Dissipative systems are still an active field of research in systems and control, due to their important applications.
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| − | 粗略地说，耗散理论对于设计线性和非线性系统的反馈控制律是有用的。V.M.Popov、J.C.Willems、D.J.Hill和P.Moylan讨论过耗散系统理论。在线性不变系统中，这被称为'''<font color="#ff8000"> 正实传递函数positive real transfer functions</font>'''，一个基本的工具就是所谓的'''<font color="#ff8000">Kalman-Yakubovich-Popov引理Kalman–Yakubovich–Popov lemma</font>'''，它关系到正实系统的状态空间和频域特性。由于其重要的应用，耗散系统一直是系统与控制领域的研究热点。
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| | == 量子耗散系统 Quantum dissipative systems == | | == 量子耗散系统 Quantum dissipative systems == |
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| − | {{main|Quantum dissipation}} | + | {{主条目|量子耗散}} |
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| | As [[quantum mechanics]], and any classical [[dynamical system]], relies heavily on [[Hamiltonian mechanics]] for which [[Time reversibility|time is reversible]], these approximations are not intrinsically able to describe dissipative systems. It has been proposed that in principle, one can couple weakly the system – say, an oscillator – to a bath, i.e., an assembly of many oscillators in thermal equilibrium with a broad band spectrum, and trace (average) over the bath. This yields a [[master equation]] which is a special case of a more general setting called the [[Lindblad equation]] that is the quantum equivalent of the classical [[Liouville's theorem (Hamiltonian)|Liouville equation]]. The well-known form of this equation and its quantum counterpart takes time as a reversible variable over which to integrate, but the very foundations of dissipative structures imposes an [[H-theorem|irreversible]] and constructive role for time. | | As [[quantum mechanics]], and any classical [[dynamical system]], relies heavily on [[Hamiltonian mechanics]] for which [[Time reversibility|time is reversible]], these approximations are not intrinsically able to describe dissipative systems. It has been proposed that in principle, one can couple weakly the system – say, an oscillator – to a bath, i.e., an assembly of many oscillators in thermal equilibrium with a broad band spectrum, and trace (average) over the bath. This yields a [[master equation]] which is a special case of a more general setting called the [[Lindblad equation]] that is the quantum equivalent of the classical [[Liouville's theorem (Hamiltonian)|Liouville equation]]. The well-known form of this equation and its quantum counterpart takes time as a reversible variable over which to integrate, but the very foundations of dissipative structures imposes an [[H-theorem|irreversible]] and constructive role for time. |