"That's a highly non-equilibrium dissipative structure that's existed for at least 300 years, and it's quite different from the non-equilibrium dissipative structures that are existing on Earth right now that have been evolving for billions of years," she said.
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Additionally, it's dissipative, meaning that it loses the energy you used to stick it to the surface.
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Or can we access it through Hawking radiation, that slow dissipative fizz of energy that gives every black hole a finite (if very, very, very long) lifetime?
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But in the nonliving world where replication doesn't usually happen, the well-adapted dissipative structures tend to be ones that are highly organized, like sand ripples and dunes crystallizing from the random dance of windblown sand.
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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. Dissipative systems stand in contrast to conservative systems. A dissipative structure is a dissipative system that has a dynamical regime that is in some sense in a reproducible steady state.
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Recently, multiwavelength dissipative soliton in an all normal dispersion fiber laser passively mode-locked with a SESAM has been generated. It is found that depending on the cavity birefringence, stable single-, dual- and triple-wavelength dissipative soliton can be formed in the laser. Its generation mechanism can be traced back to the nature of dissipative soliton.H. Zhang et al.
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Dissipative structures can depend on the presence of non-linearity in their dynamical régimes. Autocatalytic reactions provide examples of non-linear dynamics, and may lead to the natural evolution of self-organized dissipative structures.
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An operator satisfying the last two conditions is called maximally dissipative.
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In addition, multiple vector dissipative solitons with identical soliton parameters and harmonic mode-locking to the conventional dissipative vector soliton can also be formed in a passively mode-locked fiber laser with a SESAM.H. Zhang et al., "Dissipative vector solitons in a dispersionmanaged cavity fiber laser with net positive cavity dispersion", Optics Express, Vol. 17, Issue 2, pp. 455-460.
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Moreover, interaction with normal carriers leads to dissipative transport, unlike a superconductor.
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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. The Hopf decomposition states that dynamical systems can be decomposed into a conservative and a dissipative part; more precisely, it states that every measure space with a non-singular transformation can be decomposed into an invariant conservative set and an invariant dissipative set.
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As for the continuation of solutions after wave breaking, two scenarios are possible: the conservative case and the dissipative case (with the first characterized by conservation of the energy, while the dissipative scenario accounts for loss of energy due to breaking).
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For commercial uses, static dissipative rubber mats are traditionally used that are made of 2 layers (2-ply) with a tough solder resistant top static dissipative layer that makes them last longer than the vinyl mats, and a conductive rubber bottom. Conductive mats are made of carbon and used only on floors for the purpose of drawing static electricity to ground as quickly as possible. Normally conductive mats are made with cushioning for standing and are referred to as "anti-fatigue" mats. 3 ply static dissipative vinyl grounding mat shown at macro scale For a static dissipative mat to be reliably grounded it must be attached to a path to ground.
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Ghosal found that for low-order discretization schemes, such as those used in finite volume methods, the truncation error can be the same order as the subfilter scale contributions, unless the filter width \Delta is considerably larger than the grid spacing \Delta x. While even-order schemes have truncation error, they are non-dissipative, and because subfilter scale models are dissipative, even-order schemes will not affect the subfilter scale model contributions as strongly as dissipative schemes.
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In addition, it is important to prevent ESD when an electrostatic discharge sensitive component is connected with other conductive parts of the product itself. An efficient way to prevent ESD is to use materials that are not too conductive but will slowly conduct static charges away. These materials are called static dissipative and have resistivity values below 1012 ohm-meters. Materials in automated manufacturing which will touch on conductive areas of ESD sensitive electronic should be made of dissipative material, and the dissipative material must be grounded.
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Dissipative materials allow the charges to flow to ground more slowly in a more controlled manner than with conductive materials.
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While Berry's formulation was originally defined for linear Hamiltonian systems, it was soon realized by Ning and Haken that similar geometric phase can be defined for entirely different systems such as nonlinear dissipative systems that possess certain cyclic attractors. They showed that such cyclic attractors exist in a class of nonlinear dissipative systems with certain symmetries.
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Types of stretch film include bundling stretch film, hand stretch film, extended core stretch film, machine stretch film and static dissipative film.
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In 1977 Prigogine received the Nobel Prize in Chemistry for his contribution to the theory of equilibrium irreversible dissipative structures.Autobiografische Nobelpreisrede – Ilya Prigogine, 1977, nobelprize.org Schiefer's dissipative economy translates this approach to development cooperation and humanitarian aid. It thus provides an explanatory approach for the emergence and continuation of almost similar organisational landscapes in many, often very different, so-called developing countries.
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Viscount Ilya Romanovich Prigogine (; ; 28 May 2003) was a physical chemist and Nobel laureate noted for his work on dissipative structures, complex systems, and irreversibility.
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Dissipative solitons (DSs) are stable solitary localized structures that arise in nonlinear spatially extended dissipative systems due to mechanisms of self- organization. They can be considered as an extension of the classical soliton concept in conservative systems. An alternative terminology includes autosolitons, spots and pulses. Apart from aspects similar to the behavior of classical particles like the formation of bound states, DSs exhibit interesting behavior - e.g.
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And as for classical Brownian motion, this increase can be stopped by adding dissipative effects. Dissipative versions of the QMUPL, GRW and CSL model exist, where the collapse properties are left unaltered with respect to the original models, while the energy thermalizes to a finite value (therefore it can even decrease, depending on its initial value). Still, also in the dissipative model the energy is not strictly conserved. A resolution to this situation might come by considering also the noise a dynamical variable with its own energy, which is exchanged with the quantum system in such a way that the total system+noise energy is conserved.
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Another generalization of the Lieb–Robinson bounds was made to the irreversible dynamics, in which case the dynamics has a Hamiltonian part and also a dissipative part. The dissipative part is described by terms of Lindblad form, so that the dynamics \tau_t satisfies the Lindblad-Kossakowski master equation. Lieb-Robinson bounds for the irreversible dynamics were considered by in the classical context and by for a class of quantum lattice systems with finite-range interactions. Lieb-Robinson bounds for lattice models with a dynamics generated by both Hamiltonian and dissipative interactions with suitably fast decay in space, and that may depend on time, were proved by,B.
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Dissipative silencers attenuate sound by transferring sound energy to heat. Dissipative silencers are used when broadband attenuation with low pressure drop is desired. In typical ductwork, high frequencies propagate down the duct as a beam, and minimally interact with the outer, lined edges. Sound attenuators with baffles that break the line of sight or elbow attenuators with a bend provide better high frequency attenuation than conventional lined ductwork.
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A vector dissipative soliton could be formed in a laser cavity with net positive dispersion, and its formation mechanism is a natural result of the mutual nonlinear interaction among the normal cavity dispersion, cavity fiber nonlinear Kerr effect, laser gain saturation and gain bandwidth filtering. For a conventional soliton, it is a balance between only the dispersion and nonlinearity. Differing from a conventional soliton, a Vector dissipative soliton is strongly frequency chirped. It is unknown whether or not a phase-locked gain-guided vector soliton could be formed in a fiber laser: either the polarization-rotating or the phase-locked dissipative vector soliton can be formed in a fiber laser with large net normal cavity group velocity dispersion.
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Several important recent results include the realization of a Mott insulator in a driven- dissipative Bose-Hubbard system and studies of phase transitions in lattices of superconducting resonators coupled to qubits.
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He called these systems dissipative systems, because they are formed and maintained by the dissipative processes that exchange energy between the system and its environment, and because they disappear if that exchange ceases. It may be said that they live in symbiosis with their environment. Energy transformations in biology are dependent primarily on photosynthesis. The total energy captured by photosynthesis in green plants from the solar radiation is about 2 x 1023 joules of energy per year.
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Nevertheless, living systems can be stable, but in a homeostatic sense. Such homeostatic (open) systems are far- from-equilibrium and are dissipative: they need energy to maintain themselves. In dissipative controlled systems the continuous supply of energy allows a continuous transition between different supramolecular states, where systems with unexpected properties may be discovered. One of the grand challenges of Systems Chemistry is to unveil complex reactions networks, where molecules continuously consume energy to perform specific functions.
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This theory postulates that the hallmark of the origin and evolution of life is the microscopic dissipative structuring of organic pigments and their proliferation over the entire Earth surface. Present day life augments the entropy production of Earth in its solar environment by dissipating ultraviolet and visible photons into heat through organic pigments in water. This heat then catalyzes a host of secondary dissipative processes such as the water cycle, ocean and wind currents, hurricanes, etc.
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In other areas, most noticeably chaos theory, he is known for accommodating the formalism of chaos theory within general relativity.Motter A. E., Relativistic Chaos is Coordinate Invariant, Physical Review Letters 91, 231101 (2003). Along with colleagues, he also formalized the concept of doubly transient chaos in dissipative dynamical systems Motter A. E., Gruiz M., Károlyi G. and Tel T., Doubly transient chaos: Generic form of chaos in autonomous dissipative systems, Physical Review Letters 111, 194101 (2013).
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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. 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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Fluctuations about stable stationary states are extremely small except near critical points (Kondepudi and Prigogine 1998, page 323).Kondepudi, D., Prigogine, I, (1998). Modern Thermodynamics. From Heat Engines to Dissipative Structures, Wiley, Chichester, 1998, .
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The language of wandering sets can be used to give a precise, mathematical definition to the concept of a dissipative system. The notion of wandering sets in phase space was introduced by Birkhoff in 1927.
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In essence, it has been asserted that Beltrami plasma vortex structures are able to at least simulate the morphology of Type I and Type II superconductors. This occurs because the "organised" dissipative energy of the vortex configuration comprising the ions and electrons far exceeds the "disorganised" dissipative random thermal energy. The transition from disorganised fluctuations to organised helical structures is a phase transition involving a change in the condensate's energy (i.e. the ground state or zero-point energy) but without any associated rise in temperature.
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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. Recent research has seen reconsideration of Prigogine's ideas of dissipative structures in relation to biological systems.
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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 irreversible and constructive role for time.
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The bacterial flagellar motor has been proposed to follow a dissipative allosteric model, where ultrasensitivity comes as a combination of protein binding affinity and energy contributions from the proton motive force (see Flagellar motors and chemotaxis below).
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When biological systems are modeled as physical systems, in its most general abstraction, they are thermodynamic open systems that exhibit self-organised behavior, and the set/subset relations between dissipative structures can be characterized in a hierarchy.
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This systems approach to the coast was first developed by Wright and Thom in 1977 and finalized by Wright and Short in 1984. According to their dynamic and morphological characteristics, exposed sandy beaches can be classified into several morphodynamic types (Wright and Short, 1984; Short, 1996). There is a large scale of morphodynamic states, this scale ranges from the "dissipative state" to the "reflective extremes". Dissipative beaches are flat, have fine sand, incorporating waves that tend to break far from the intertidal zone and dissipate force progressively along wide surf zones.
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A related topic is the probability that life would emerge, which has been discussed in several studies, for example by Russell Doolittle.Russell Doolittle, "The Probability and Origin of Life" in Scientists Confront Creationism (1984) Ed. Laurie R. Godfrey, p. 85 In 2009, physicist Karo Michaelian published a thermodynamic dissipation theory for the origin of life in which the fundamental molecules of life; nucleic acids, amino acids, carbohydrates (sugars), and lipids are considered to have been originally produced as microscopic dissipative structures (through Prigogine's dissipative structuring ) as pigments at the ocean surface to absorb and dissipate into heat the UVC flux of solar light arriving at Earth's surface during the Archean, just as do organic pigments in the visible region today. These UVC pigments were formed through photochemical dissipative structuring from more common and simpler precursor molecules like HCN and H2O under the UVC flux of solar light .
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In an electrical substation a ground (earth) mat is a mesh of conductive material installed at places where a person would stand to operate a switch or other apparatus; it is bonded to the local supporting metal structure and to the handle of the switchgear, so that the operator will not be exposed to a high differential voltage due to a fault in the substation. In the vicinity of electrostatic sensitive devices, a ground (earth) mat or grounding (earthing) mat is used to ground static electricity generated by people and moving equipment. There are two types used in static control: Static Dissipative Mats, and Conductive Mats. A static dissipative mat that rests on a conductive surface (commonly the case in military facilities) are typically made of 3 layers (3-ply) with static dissipative vinyl layers surrounding a conductive substrate which is electrically attached to ground (earth).
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These funds flow into a national economy mostly concentrated in the cities. There, they are then largely used in an unproductive manner. This whole sector of the economy which is dependent on a continuous external input Schiefer defines as dissipative economy.
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The non equilibrium thermodynamics has been applied for explaining how ordered structures e.g. the biological systems, can develop from disorder. Even if Onsager's relations are utilized, the classical principles of equilibrium in thermodynamics still show that linear systems close to equilibrium always develop into states of disorder which are stable to perturbations and cannot explain the occurrence of ordered structures. Prigogine called these systems dissipative systems, because they are formed and maintained by the dissipative processes which take place because of the exchange of energy between the system and its environment and because they disappear if that exchange ceases.
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Sometimes also antimetrical networks are of interest. These are networks where the input and output impedances are the duals of each other.Matthaei et al, pp. 70-72. ;Lossless network: A lossless network is one which contains no resistors or other dissipative elements.
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He is an elected Fellow of the American Physical Society, for "pioneering contributions to theories of dissipative quantum dynamics and for innovative Monte Carlo approaches to quantum and classical studies of critical phenomena." He coauthored the book on modern theory of superfluidity.
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In 1973, the use of PCBs in "open" or "dissipative" sources (such as plasticisers in paints and cements, casting agents, fire retardant fabric treatments and heat stabilizing additives for PVC electrical insulation, adhesives, paints and waterproofing, railroad ties) was banned in Sweden.
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Lord Kelvin deduced that a subset of the above-mentioned irreversible dissipative processes will occur unless a process is governed by a "perfect thermodynamic engine". The processes that Lord Kelvin identified were friction, diffusion, conduction of heat and the absorption of light.
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In physics, the dissipation factor (DF) is a measure of loss-rate of energy of a mode of oscillation (mechanical, electrical, or electromechanical) in a dissipative system. It is the reciprocal of quality factor, which represents the "quality" or durability of oscillation.
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Modern Thermodynamics. From Heat Engines to Dissipative Structures, John Wiley, Chichester, , pp. 115–116. The above definition, equation (1), of the absolute temperature is due to Kelvin. It refers to systems closed to transfer of matter, and has special emphasis on directly experimental procedures.
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Mangroves and small dune formations are the most characteristic element of the coastal relief. The beaches are dissipative, fine golden sand on the north and darke volcanic in the south, with annual variations in the coastline that can be labeled due to winter storms.
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Hydrodynamic pilot-wave analogs have been able to duplicate the double slit experiment, tunneling, quantized orbits, and numerous other quantum phenomena and as such pilot-wave theories are experiencing a resurgence in interest. Coulder and Fort note in their 2006 paper that pilot-waves are nonlinear dissipative systems sustained by external forces. A dissipative system is characterized by the spontaneous appearance of symmetry breaking (anisotropy) and the formation of complex, sometimes chaotic or emergent, dynamics where interacting fields can exhibit long range correlations. In SED the zero point field (ZPF) plays the role of the pilot wave that guides real particles on their way.
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In those branches of mathematics called dynamical systems and ergodic theory, the concept of a wandering set formalizes a certain idea of movement and mixing in such systems. When a dynamical system has a wandering set of non- zero measure, then the system is a dissipative system. This is very much the opposite of a conservative system, for which the ideas of the Poincaré recurrence theorem apply. Intuitively, the connection between wandering sets and dissipation is easily understood: if a portion of the phase space "wanders away" during normal time-evolution of the system, and is never visited again, then the system is dissipative.
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In his "Thermodynamic Dissipation Theory of the Origin and Evolution of Life", Karo Michaelian has taken the insight of Boltzmann and the work of Prigogine to its ultimate consequences regarding the origin of life. This theory postulates that the hallmark of the origin and evolution of life is the microscopic dissipative structuring of organic pigments and their proliferation over the entire Earth surface. Present day life augments the entropy production of Earth in its solar environment by dissipating ultraviolet and visible photons into heat through organic pigments in water. This heat then catalyzes a host of secondary dissipative processes such as the water cycle, ocean and wind currents, hurricanes, etc.
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There are however various types of systems which are capable of producing solitary structures and in which dissipation plays an essential role for their formation and stabilization. Although research on certain types of these DSs has been carried out for a long time (for example, see the research on nerve pulses culminating in the work of Hodgkin and Huxley in 1952), since 1990 the amount of research has significantly increased (see e.g. ) Possible reasons are improved experimental devices and analytical techniques, as well as the availability of more powerful computers for numerical computations. Nowadays, it is common to use the term dissipative solitons for solitary structures in strongly dissipative systems.
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See also section "Introduction" of: Rafael Benguria, Haim Brezis, Elliott H. Lieb: The Thomas–Fermi–von Weizsäcker theory of atoms and molecules, Commun. Math. Phys., Volume 79, pp. 167–180 (1981), . The von Weizsäcker correction term isSee also Roumen Tsekov: Dissipative time dependent density functional theory, Int.
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In 3He-4He mixtures, like in dilution refrigerators, quantum turbulence can be created far below 1 K if the velocities exceed certain critical values. For velocities above the critical velocity there is a dissipative interaction between the superfluid component and the 3He which is called mutual friction.
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Prigogine created the term dissipative structure.Ilya Prigogine: Wissenschaft und schöpferische Evolution – PDF 490 kB, Herbert J. Klima, holimen.tvIlya Prigogine Botschafter des Dialogs mit der Natur – PDF 167 kB, Vasileios Basios, smn.germany.de Since then, many scientists have confirmed that this model is applicable to any open system.
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If the system is conservative (i.e., there is no dissipation), a volume element of the phase space will stay the same along a trajectory. Thus the sum of all Lyapunov exponents must be zero. If the system is dissipative, the sum of Lyapunov exponents is negative.
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The photoconversion from the orange to red form has a poor light efficiency (very low quantum yield), which helps to ensure the protein's photoprotective role only functions during high light conditions; otherwise, the dissipative NPQ process could unproductively divert light energy away from photosynthesis under light-limiting conditions.
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Non-Hermitian quantum mechanicsN. Moiseyev, "Non-Hermitian Quantum Mechanics", Cambridge University Press, Cambridge, 2011 is the study of quantum-mechanical Hamiltonians that are not Hermitian. Notably, they appear in the study of dissipative systems. Also, non-Hermitian Hamiltonians with unbroken parity- time (PT) symmetry have all real eigenvalues.
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In thermodynamics, dissipation is the result of an irreversible process that takes place in homogeneous thermodynamic systems. A dissipative process is a process in which energy (internal, bulk flow kinetic, or system potential) is transformed from some initial form to some final form; the capacity of the final form to do mechanical work is less than that of the initial form. For example, heat transfer is dissipative because it is a transfer of internal energy from a hotter body to a colder one. Following the second law of thermodynamics, the entropy varies with temperature (reduces the capacity of the combination of the two bodies to do mechanical work), but never decreases in an isolated system.
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For example, the optical components can be found in a closed volume containing only low dissipative elements, while the cube corners are exterior to this volume. Furthermore, the enclosure which contains the interferometer is almost entirely decoupled from the rest of the instrument by Multi-Layer Insulation (MLI). This determines a very good thermal stability for the optics of the interferometer: the temporal and spatial gradients are less than 1 °C, which is important for the radiometric calibration performance. Furthermore, other equipments are either sealed in specific enclosures, such as dissipative electronics or LASER sources, or thermally controlled through the thermal control section of the main structure, for example the scan mechanisms or the blackbody.
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The full trace of the developments of various important aspects of the DPD methodology since it was first proposed in the early 1990s can be found in "Dissipative Particle Dynamics: Introduction, Methodology and Complex Fluid Applications – A Review". The state-of-the-art in DPD was captured in a CECAM workshop in 2008.Dissipative Particle Dynamics: Addressing deficiencies and establishing new frontiers , CECAM workshop, July 16–18, 2008, Lausanne, Switzerland. Innovations to the technique presented there include DPD with energy conservation; non-central frictional forces that allow the fluid viscosity to be tuned; an algorithm for preventing bond crossing between polymers; and the automated calibration of DPD interaction parameters from atomistic molecular dynamics.
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Thermodynamic Models , Modeling in Ecological Economics (Ch. 18) Thermoeconomics thus adapts the theories in non-equilibrium thermodynamics, in which structure formations called dissipative structures form, and information theory, in which information entropy is a central construct, to the modeling of economic activities in which the natural flows of energy and materials function to create and allocate resources. In thermodynamic terminology, human economic activity (as well as the activity of the human life units which make it up) may be described as a dissipative system, which flourishes by consuming free energy in transformations and exchange of resources, goods, and services. The article on Complexity economics also contains concepts related to this line of thinking.
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Dr Anne Dambricourt-Malassé (born 1959) is a paleoanthropologist at the French National Centre for Scientific Research (CNRS). She has advocated a highly controversial non-Darwinian view of human evolution with theories similar to punctuated equilibrium, auto-organization and dissipative structures, with natural selection not being the exclusive method of evolution.
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This approach is fraught with various difficulties; it works well for only a handful of exactly solvable models.Dean J. Driebe, Fully Chaotic Maps and Broken Time Symmetry, (1999) Kluwer Academic Abstract mathematical tools used in the study of dissipative systems include definitions of mixing, wandering sets, and ergodic theory in general.
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After studying chemistry at the universities of Antwerp and Ghent, Bodifee studied astronomy, focusing on star formation. At the University of Brussels he conducted scientific research on the origin and evolution of galaxies and obtained a PhD in science with a doctoral thesis titled Oscillating Star Formation and Dissipative Structures in Galaxies.
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The swash motion plays the primary role in the formation of morphological features and their changes in the swash zone. The swash action also plays an important role as one of the instantaneous processes in wider coastal morphodynamics. Figure 1. Beach classification by Wright and Short (1983) showing dissipative, intermediate, and reflective beaches.
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He is currently interested in the statistical properties of large scales in turbulenceV. Dallas, S. Fauve and A. Alexakis, « Statistical equilibria of large scales in dissipative hydrodynamic turbulence », Phys. Rev. Lett., 115, (2015), p. 204501V. Shukla, S. Fauve and M. Brachet, « Statistical theory of reversals in two-dimensional confined turbulent flows », Phys. Rev.
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If c_p is constant, then \tilde h=\tilde \theta = T/T_\infty. The temperature inside the boundary layer will increase even though the plate temperature is maintained at the same temperature as ambient, due to dissipative heating and of course, these dissipation effects are only pronounced when the Mach number M is large.
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Reaction–diffusion systems have attracted much interest as a prototype model for pattern formation. Patterns such as fronts, spirals, targets, hexagons, stripes and dissipative solitons are found in various types of reaction- diffusion systems in spite of large discrepancies e.g. in the local reaction terms. Such patterns have been dubbed "Turing patterns".
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This formalism became known as Classical Irreversible Thermodynamics and Prigogine was awarded the Nobel Prize in Chemistry in 1977 "for his contributions to non-equilibrium thermodynamics, particularly the theory of dissipative structures". The analysis by Prigogine showed that if a system were left to evolve under an imposed external potential, material could spontaneously organize (lower its entropy) forming what he called "dissipative structures" which would increase the dissipation of the externally imposed potential (augment the global entropy production). Non-equilibrium thermodynamics has since been successfully applied to the analysis of living systems, from the biochemical production of ATP to optimizing bacterial metabolic pathwaysUnrean, P., Srienc, F. (2011) Metabolic networks evolve towards states of maximum entropy production, Metabolic Engineering 13, 666–673. to complete ecosystems.
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Pribram's holonomic model of brain function did not receive widespread attention at the time, but other quantum models have been developed since, including brain dynamics by Jibu & Yasue and Vitiello's dissipative quantum brain dynamics. Though not directly related to the holonomic model, they continue to move beyond approaches based solely in classic brain theory.
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Dissipative structure theory led to pioneering research in self-organizing systems, as well as philosophical inquiries into the formation of complexity on biological entities and the quest for a creative and irreversible role of time in the natural sciences. See the criticism by Joel Keizer and Ronald Fox. Also on Academia.edu. Retrieved 16 October 2016.
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With Bruno Coppi and others he investigated dissipative instabilities in plasmas. With Ira B. Bernstein and Martin Kruskal he did research on BGK modes (nonlinear wave solutions in plasma physics). In the 1970s he worked on Hamiltonian dynamics in chaos theory. In 1979 he published Greene's criterion for the collapse of tori in KAM theory.
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In Fig. 7 we see that kinematic variables lie in the left column while dynamic variables lie in the right one. The diagram shows three phenomenological equations: those connecting two variables on the same level describe a reversible relation (i.e. a non-dissipative relation), while those linking force with velocity describe an irreversible relation (i.e.
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She is also an affiliate of the Beckman Institute for Science and Technology. Makri works in the area of theoretical chemical physics. She has developed new theoretical approaches to simulating the dynamics of quantum mechanical phenomena. Makri has developed novel methods for calculating numerically exact path integrals for the simulation of system dynamics in harmonic dissipative environments.
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The deputy of the State Assembly of Bashkortostan. A member of the political party " United Russia". Research interests: the physics of superconductivity meterially; stochastic diffusion processes in dissipative systems, dynamic exchange interactions in condensed matter. He developed the theory of dynamical exchange interactions in condensed matter systems installed mathematical correlations in a system with broken symmetry.
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Prefabricated sound attenuators rose to prominence in the late 1950s-early 1960s. Several manufacturers were among the first to produce and test prefabricated sound attenuators: Koppers, Industrial Acoustics Company, Industrial Sound Control, and Elof Hansson. Though rectangular dissipative attenuators are the most common variant of attenuators used today in architectural acoustics noise control, other design options exist.
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Most of these recent frequency-dependent models are established via the analysis of the complex wave number and are then extended to transient wave propagation.Thomas L. Szabo, 2004, Diagnostic ultrasound imaging, Elsevier Academic Press. The multiple relaxation model considers the power law viscosity underlying different molecular relaxation processes. Szabo proposed a time convolution integral dissipative acoustic wave equation.
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After earning bachelor's and master's degrees at the University of Auckland, Kirk went to the University of Cambridge for doctoral studies. She completed her Ph.D. in 1990; her dissertation, Destruction of tori in dissipative flows, was supervised by Nigel Weiss. She was a postdoctoral researcher at the University of California, Berkeley and at the California Institute of Technology.
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In the case of linear invariant systems, 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. Dissipative systems are still an active field of research in systems and control, due to their important applications.
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All real-world oscillator systems are thermodynamically irreversible. This means there are dissipative processes such as friction or electrical resistance which continually convert some of the energy stored in the oscillator into heat in the environment. This is called damping. Thus, oscillations tend to decay with time unless there is some net source of energy into the system.
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A series of various branches of non-linear mathematics catastrophe theory, the fractal theory, the theory of "dissipative structures", the chaos theory have led to what Boutot (1993) called "the morphologic revolution", which has deeply modified the conception of forms in space. Theoretical neuromorphology discards morphogenesis (the way forms have been made) to limit its purpose to realised forms.
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In chaos theory, Wada basins arise very frequently. Usually, the Wada property can be seen in the basin of attraction of dissipative dynamical systems. But the exit basins of Hamiltonian system can also show the Wada property. In the context of the chaotic scattering of systems with multiple exit, basin of exit shows the Wada property.
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Jan Camiel Willems (18 September 1939 – 31 August 2013) was a Belgian mathematical system theorist who has done most of his scientific work while residing in the Netherlands and the United States. He is most noted for the introduction of the notion of a dissipative system and for the development of the behavioral approach to systems theory.
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Transitions between beach states are often caused by changes in wave energy, with storms causing reflective beach profiles to flatten (offshore movement of sediment under steeper waves), thus adopting a more dissipative profile. Morphodynamic processes are also associated with other coastal landforms, for example spur and groove formation topography on coral reefs and tidal flats in infilling estuaries.
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In this research, Haddad has brought a longstanding research theme to fruition by his work on vector dissipative systems approaches to large-scale nonlinear dynamical systems. This work has broad application to large-scale aerospace systems, air traffic control systems, power and energy grid systems, manufacturing and processing systems, transportation systems, communication and information networks, integrative biological systems, biological neural networks, biomolecular and biochemical systems, nervous systems, immune systems, environmental and ecological systems, molecular, quantum, and nanoscale systems, particulate and chemical reaction systems, and economic and financial systems, to name but a few examples. His most recent book in this area, Stability and Control of Large-Scale Dynamical Systems: A Vector Dissipative Systems Approach, Princeton, NJ: Princeton University Press, 2011, addresses highly interconnected and mutually interdependent complex aerospace dynamical systems.
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Only in quasi-static process can we define intensive quantities (like Pressure, Temperature, Specific volume, Specific entropy) of the system at every instant during the whole process; Otherwise, since no internal equilibrium is established, different parts of the system would have different values of these quantities. Any reversible process is a quasi-static one. However, quasi-static processes involving entropy production are not reversible. An example of a quasi-static process that is not reversible is a compression against a system with a piston subject to friction-- although the system is always in thermal equilibrium, the friction ensures the generation of dissipative entropy, which directly goes against the definition of reversible; alternatively, one can say that friction would generate heat and dissipative entropy only if the movement of the piston were not infinitely slow.
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The word friction comes from the Latin "frictionem", which means rubbing. This term is used to describe all those dissipative phenomena, capable of producing heat and of opposing the relative motion between two surfaces. There are two main types of friction: ; Static friction: Which occurs between surfaces in a fixed state, or relatively stationary. ; Dynamic friction: Which occurs between surfaces in relative motion.
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In the analysis above, no dissipative elements (resistors) have been considered. That means that the power is transmitted without losses from the input voltage source to the load. However, parasitic resistances exist in all circuits, due to the resistivity of the materials they are made from. Therefore, a fraction of the power managed by the converter is dissipated by these parasitic resistances.
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The development agencies, from the large international and national organisations to the small non-governmental organisations, thus appear as dissipative structures. They function only through the provision of a regular inflow of development aid. The funding of the internal players is guaranteed by an external inflow of money by the external agencies. These ensure their outflow through project funding and the like.
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Various principles have been proposed by diverse authors for over a century. According to Glansdorff and Prigogine (1971, page 15),Glansdorff, P., Prigogine, I. (1971). Thermodynamic Theory of Structure, Stability and Fluctuations, Wiley-Interscience, London. in general, these principles apply only to systems that can be described by thermodynamical variables, in which dissipative processes dominate by excluding large deviations from statistical equilibrium.
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These indicate that the mean free time of quarks and gluons in the QGP may be comparable to the average interparticle spacing: hence the QGP is a liquid as far as its flow properties go. This is very much an active field of research, and these conclusions may evolve rapidly. The incorporation of dissipative phenomena into hydrodynamics is another active research area.
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Concepts governing the dynamics and structure of emergent patterns in open dissipative systems; mixed reality; prediction and control of fractal network dynamics; entrainment of cancer cells; energy conversion, storage, and distribution; dissipate wave-particle systems; solitons; homeopathy; flames and shock waves; turbulence; reverse osmosis and filtration with fractal absorbers; conceptual networks; quantitative measures for knowledge and intelligence; natural language parsing.
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Rayleigh (1873) (and in Sections 81 and 345 of Rayleigh (1896/1926)) introduced the dissipation function for the description of dissipative processes involving viscosity. More general versions of this function have been used by many subsequent investigators of the nature of dissipative processes and dynamical structures. Rayleigh's dissipation function was conceived of from a mechanical viewpoint, and it did not refer in its definition to temperature, and it needed to be 'generalized' to make a dissipation function suitable for use in non- equilibrium thermodynamics. Studying jets of water from a nozzle, Rayleigh (1878, 1896/1926) noted that when a jet is in a state of conditionally stable dynamical structure, the mode of fluctuation most likely to grow to its full extent and lead to another state of conditionally stable dynamical structure is the one with the fastest growth rate.
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This recasting of the problem comes at a price: the N-body Lagrangian depends on all the time derivatives of the curves traced by all particles, i.e. the Lagrangian is infinite-order. However, much progress was made in examining the unresolved issue of quantizing the theory. Also, this formulation recovers the Darwin Lagrangian, from which the Breit equation was originally derived, but without the dissipative terms.
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Equilibrium and Non-equilibrium Statistical Mechanics, Wiley-Interscience, New York, , Section 3.2, pages 64-72. dissipative structure, and non-linear dynamical structure. One problem of interest is the thermodynamic study of non- equilibrium steady states, in which entropy production and some flows are non- zero, but there is no time variation of physical variables. One initial approach to non-equilibrium thermodynamics is sometimes called 'classical irreversible thermodynamics'.
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The artificial products can be considered, as it was explained by Prigogine with collaborators, as the far-from-equilibrium objects (the dissipative structures), and to create and maintain them, the fluxes of matter and energy are necessary to run through the system. In our case, energy comes in the form of human efforts L and work of external sources P that can be used by means of the appropriate equipment. The creation of dissipative structures leads to decrease in entropy, and utility U can be considered as a close relation to entropy S, though does not coincides with it. Considering that changes of internal energy in production of things can be neglected, one can write a thermodynamic relation Reconciliation of the two points of view on the phenomenon of production leads to a unified picture that enables us to relate some aspects of our observations of economic phenomena to physical principles.
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Nancy Makri (born September 5, 1962) is the Edward William and Jane Marr Gutgsell Endowed Professor of Chemistry and Physics at the University of Illinois at Urbana–Champaign, where she is the principal investigator of the Makri Research Group for the theoretical understanding of condensed phase quantum dynamics. She studies theoretical quantum dynamics of polyatomic systems, and has developed methods for long-time numerical path integral simulations of quantum dissipative systems.
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They may be said to live in symbiosis with their environment. The method which Prigogine used to study the stability of the dissipative structures to perturbations is of very great general interest. It makes it possible to study the most varied problems, such as city traffic problems, the stability of insect communities, the development of ordered biological structures and the growth of cancer cells to mention but a few examples.
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The original theory, a reaction–diffusion theory of morphogenesis, has served as an important model in theoretical biology. Reaction–diffusion systems have attracted much interest as a prototype model for pattern formation. Patterns such as fronts, hexagons, spirals, stripes and dissipative solitons are found as solutions of Turing-like reaction–diffusion equations. Turing proposed a model wherein two homogeneously distributed substances (P and S) interact to produce stable patterns during morphogenesis.
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In recent times, reaction–diffusion systems have attracted much interest as a prototype model for pattern formation. The above-mentioned patterns (fronts, spirals, targets, hexagons, stripes and dissipative solitons) can be found in various types of reaction–diffusion systems in spite of large discrepancies e.g. in the local reaction terms. It has also been argued that reaction–diffusion processes are an essential basis for processes connected to morphogenesis in biologyL.
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In this range, the energy input from nonlinear interactions and the energy drain from viscous dissipation are in exact balance. The small scales have high frequency, causing turbulence to be locally isotropic and homogeneous. ; Taylor microscales : The intermediate scales between the largest and the smallest scales which make the inertial subrange. Taylor microscales are not dissipative scales, but pass down the energy from the largest to the smallest without dissipation.
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Since the 1990s, swash hydrodynamics have been more actively investigated by coastal researchers, such as Hughes M.G., Masselink J. and Puleo J.A., contributing to the better understanding of the morphodynamics in the swash zone including turbulence, flow velocities, interaction with the beach groundwater table, and sediment transport. However, the gaps in understanding still remain in swash research including turbulence, sheet flow, bedload sediment transport and hydrodynamics on ultra-dissipative beaches.
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Let A be a linear operator defined on a linear subspace D(A) of the Banach space X. Then A generates a contraction semigroup if and only ifEngel and Nagel Theorem II.3.15, Arent et al. Theorem 3.4.5, Staffans Theorem 3.4.8 # D(A) is dense in X, # A is closed, # A is dissipative, and # A − λ0I is surjective for some λ0> 0, where I denotes the identity operator.
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Let A be a linear operator defined on a linear subspace D(A) of the Banach space X. Then A generates a quasi contraction semigroup if and only if # D(A) is dense in X, # A is closed, # A is quasidissipative, i.e. there exists a ω ≥ 0 such that A − ωI is dissipative, and # A − λ0I is surjective for some λ0 > ω, where I denotes the identity operator.
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This is an example of Pomeau–Manneville dynamics. In dynamical systems, intermittency is the irregular alternation of phases of apparently periodic and chaotic dynamics (Pomeau–Manneville dynamics), or different forms of chaotic dynamics (crisis- induced intermittency). Pomeau and Manneville described three routes to intermittency where a nearly periodic system shows irregularly spaced bursts of chaos. Yves Pomeau and Paul Manneville, Intermittent Transition to Turbulence in Dissipative Dynamical Systems, Commun. Math. Phys. vol.
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Rembert A. Duine (born 1975) is a professor of theoretical physicsInstitute For Theoretical Physics at Utrecht University in the Netherlands and a part- time professor at Eindhoven University of Technology in the Netherlands. He wrote his PhD thesis under the supervision of Henk Stoof, working on ultracold atoms. He has authored and co-authored more than 100arxiv.org papers on spintronics, ultracold atoms, and condensation in dissipative systems like photons, magnons, and excitons.
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Synchronization of chaos is a phenomenon that may occur when two, or more, dissipative chaotic systems are coupled. Because of the exponential divergence of the nearby trajectories of chaotic systems, having two chaotic systems evolving in synchrony might appear surprising. However, synchronization of coupled or driven chaotic oscillators is a phenomenon well established experimentally and reasonably well-understood theoretically. The stability of synchronization for coupled systems can be analyzed using master stability.
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However, negative entropy (i.e. increased order, structure or self-organisation) can spontaneously appear in an open nonlinear thermodynamic system that is far from equilibrium, so long as this emergent order accelerates the overall flow of entropy in the total system. The 1977 Nobel Prize in Chemistry was awarded to thermodynamicist Ilya Prigogine for his theory of dissipative systems that described this notion. Prigogine described the principle as "order through fluctuations" or "order out of chaos".
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According to IEEE Standard 145–1993, realized gain differs from the above definitions of gain in that it is "reduced by the losses due to the mismatch of the antenna input impedance to a specified impedance." This mismatch induces losses above the dissipative losses described above; therefore, realized gain will always be less than gain. Gain may be expressed as absolute gain if further clarification is required to differentiate it from realized gain.
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Presently, these advancements are increasing the importance of O-rings. Since O-rings encompass the areas of chemistry and material science, any advancement in nano-rubber will affect the O-ring industry. Already, there are elastomers filled with nano-carbon and nano-PTFE and molded into O-rings used in high- performance applications. For example, carbon nanotubes are used in electrostatic dissipative applications and nano-PTFE is used in ultra pure semiconductor applications.
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The compact finite difference formulation, or Hermitian formulation, is a numerical method to compute finite difference approximations. Such approximations tend to be more accurate for their stencil size (i.e. their compactness) and, for hyperbolic problems, have favorable dispersive error and dissipative error properties when compared to explicit schemes. A disadvantage is that compact schemes are implicit and require to solve a diagonal matrix system for the evaluation of interpolations or derivatives at all grid points.
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Peter Hänggi (born November 29, 1950) is a theoretical physicist from Switzerland, Professor of Theoretical Physics at the University of Augsburg. He is best known for his original works on Brownian motion and the Brownian motor concept, stochastic resonance and dissipative systems (classical and quantum mechanical). Other topics include, driven quantum tunneling, such as the discovery of coherent destruction of tunneling (CDT), phononics, relativistic statistical mechanics and the foundations of classical and quantum thermodynamics.
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If the granular material is driven harder such that contacts between the grains become highly infrequent, the material enters a gaseous state. Correspondingly, one can define a granular temperature equal to the root mean square of grain velocity fluctuations that is analogous to thermodynamic temperature. Unlike conventional gases, granular materials will tend to cluster and clump due to the dissipative nature of the collisions between grains. This clustering has some interesting consequences.
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C. major s.l. occurs in open, dissipative and flat sandy beaches, mostly in deep galleries in the intertidal zone, but also in shallow subtidal depths of 2–3 m. It has a very large geographic distribution across Pan-American coastlines. In the Atlantic coastline, the distribution occurs from North Carolina to Santa Catarina, although with a large hiatus from Southern Texas to Pará, being therein only sporadically found in Colombia and Venezuela.
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In mathematics, a measure-preserving dynamical system is an object of study in the abstract formulation of dynamical systems, and ergodic theory in particular. Measure-preserving systems obey the Poincaré recurrence theorem, and are a special case of conservative systems. They provide the formal, mathematical basis for a broad range of physical systems, and, in particular, many systems from classical mechanics (in particular, most non-dissipative systems) as well as systems in thermodynamic equilibrium.
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See dynamical systems and chaos theory, dissipative structures One could say that time is a parameterization of a dynamical system that allows the geometry of the system to be manifested and operated on. It has been asserted that time is an implicit consequence of chaos (i.e. nonlinearity/irreversibility): the characteristic time, or rate of information entropy production, of a system. Mandelbrot introduces intrinsic time in his book Multifractals and 1/f noise.
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This has important implications for magnetic dynamos. In fact, a very high electrical conductivity translates into high magnetic Reynolds numbers, which indicates that the plasma will be turbulent. In fact, the conventional views on flux freezing in highly conducting plasmas are inconsistent with the phenomenon of spontaneous stochasticity. It has become a standard argument even in textbooks, unfortunately, that magnetic flux freezing should hold better and better as magnetic diffusivity tends to zero (non-dissipative regime).
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His studies have been documented by way of a number of articles and the online article repository of the Indian Academy of Sciences has listed 134 of them. Besides, he has published three books, including Dissipative Phenomena in Condensed Matter: Some Applications, co-authored with Sushanta Kumar Dattagupta and Kinetics of Phase Transitions, an edited work. He has also guided several students in their studies and serves as the associate editor of Phase Transitions journal of Taylor and Francis.
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Air ionisers are often used in places where work is done involving static- electricity-sensitive electronic components (like in microelectronics cleanrooms), to eliminate the build-up of static charges on non-conductors. As those elements are very sensitive to electricity, they cannot be grounded because the discharge will destroy them as well. Usually, the work is done over a special dissipative table mat, which allows a very slow discharge, and under the air gush of an ioniser.
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Being explicitly based on the Hilbert space language, the KvN classical mechanics adopts many techniques from quantum mechanics, for example, perturbation and diagram techniques as well as functional integral methods. The KvN approach is very general, and it has been extended to dissipative systems, relativistic mechanics, and classical field theories. The KvN approach is fruitful in studies on the quantum-classical correspondence as it reveals that the Hilbert space formulation is not exclusively quantum mechanical.Bracken, A. J. (2003).
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Normally, both the mat and the wrist strap are connected to ground by using a common point ground system (CPGS). In computer repair shops and electronics manufacturing workers must be grounded before working on devices sensitive to voltages capable of being generated by humans. For that reason static dissipative mats can be and are also used on production assembly floors as "floor runner" along the assembly line to draw static generated by people walking up and down.
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It is, however, more mathematically sophisticated and systematic. Newton's laws can include non-conservative forces like friction; however, they must include constraint forces explicitly and are best suited to Cartesian coordinates. Lagrangian mechanics is ideal for systems with conservative forces and for bypassing constraint forces in any coordinate system. Dissipative and driven forces can be accounted for by splitting the external forces into a sum of potential and non-potential forces, leading to a set of modified Euler–Lagrange (EL) equations.
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Kenneth Young (楊綱凱 1947) is a Professor of Physics at the Chinese University of Hong Kong (CUHK). He obtained his BSc in Physics in 1969, and his PhD in Physics and Mathematics at the California Institute of Technology, USA. He took a position at CUHK in 1973, and embarked on a highly regarded career as a theoretical physicist.Kenneth YOUNG Professor of Physics He has produced extensive research in elementary particles, field theory, high energy phenomenology and dissipative systems.
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Thermosynthesis is a theoretical mechanism proposed by Anthonie Muller for biological use of the free energy in a temperature gradient to drive energetically uphill anabolic reactions. It makes use of this thermal gradient, or the dissipative structure of convection in this gradient, to drive a microscopic heat engine that performs condensation reactions. Thus negative entropy is generated. The components of the biological thermosynthesis machinery concern progenitors of today's ATP synthase, which functions according to the binding change mechanism, driven by chemiosmosis.
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The generalization is considered to be a good candidate for formulating a theory of non-extensive thermodynamics. The resulting theory is not intended to replace Boltzmann–Gibbs statistics, but rather supplement it, such as in the case of anomalous systems characterised by non-ergodicity or metastable states. One experimental verification of the predictions of Tsallis statistics concerned cold atoms in dissipative optical lattices. Eric Lutz made an analytical prediction in 2003 which was verified in 2006 by a London team.
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The stars in the central region of NGC 3311 and in the halo are very old, with ages of over 10 Gyrs. However the stars in the central galaxy have a higher metallicity than the halo suggesting the stars in the stars in the central galaxy formed in a rapid but short period of star formation that occurred early on though a gas-rich dissipative collapse while the stars in halo formed in smaller accreted satellite galaxies with more extended star formation.
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On the basis of more than fifteen years of research, he analyses this nexus using the example of Guinea- Bissau. He reconstructs the overall socio-political developments, and examines the effects of development aid specifically on agrarian societies. Given the obvious failures of both theory and practice of development cooperation, based on the terminology and inspired by the work of Ilya Prigogines, Schiefer conceived the concept of "dissipative economy". In the seventies the chemist Ilya Prigogine studied the theory of non-equilibrium dynamics.
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" Prigogine in his 1977 Nobel LecturePrigogine, I. (1977). Time, Structure and Fluctuations, Nobel Lecture. said: "... non-equilibrium may be a source of order. Irreversible processes may lead to a new type of dynamic states of matter which I have called “dissipative structures”." Glansdorff and Prigogine (1971) wrote on page xx: "Such 'symmetry breaking instabilities' are of special interest as they lead to a spontaneous 'self-organization' of the system both from the point of view of its space order and its function.
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In fluid dynamics, an isentropic flow is a fluid flow that is both adiabatic and reversible. That is, no heat is added to the flow, and no energy transformations occur due to friction or dissipative effects. For an isentropic flow of a perfect gas, several relations can be derived to define the pressure, density and temperature along a streamline. Note that energy can be exchanged with the flow in an isentropic transformation, as long as it doesn't happen as heat exchange.
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Fogg has a philosophy in life to never worry about things which are beyond his control but to leave no stone unturned if they are. He is a balanced fellow not just in his thought processes but also his physiognomy which is a true manifestation of his psychology. He is a man of regular and precise habits which may border eccentricity. He doesn't like to be drawn into useless confrontations as he believes them to be utterly dissipative akin to friction.
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Such straps are used when workers need to be mobile in a work area and a grounding cable would get in the way. They are used particularly in an operating theatre, where oxygen or explosive anesthetic gases are used. "Wireless" or "dissipative" wrist straps are available, which claim to protect against ESD without needing a ground wire, typically by air ionization or corona discharge. These are widely regarded as ineffective, if not fraudulent, and examples have been tested and shown not to work.
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Although the second law of thermodynamics can determine the equilibrium state that a system will evolve to, and steady states in dissipative systems can sometimes be predicted, there exists no general rule to predict the time evolution of systems distanced from equilibrium, e.g. chaotic systems, if they do not approach an equilibrium state. Their predictability usually deteriorates with time and to quantify predictability, the rate of divergence of system trajectories in phase space can be measured (Kolmogorov–Sinai entropy, Lyapunov exponents).
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Due to their number and variety of architectures, it is difficult to give a precise definition for a CNN processor. From an architecture standpoint, CNN processors are a system of finite, fixed-number, fixed-location, fixed-topology, locally interconnected, multiple-input, single-output, nonlinear processing units. The nonlinear processing units are often referred to as neurons or cells. Mathematically, each cell can be modeled as a dissipative, nonlinear dynamical system where information is encoded via its initial state, inputs and variables used to define its behavior.
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This means that most of the dissipative mechanisms may provide enough energy only at distances further from the solar corona. More probably, the Alfvén waves are responsible for the acceleration of the solar wind in coronal holes. The theory initially developed by Parker of micro-nanoflares is one of those explaining the heating of the corona as the dissipation of electric currents generated by a spontaneous relaxation of the magnetic field towards a configuration of lower energy. The magnetic energy is thus transformed into Joule heating.
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Notice that by virtue of the principle of universality, it is expected that the particular description of the bath will not affect the essential features of the dissipative process, as far as the model contains the minimal ingredients to provide the effect. The simplest way to model the bath was proposed by Feynman and Vernon in a seminal paper from 1963. In this description the bath is a sum of an infinite number of harmonic oscillators, that in quantum mechanics represents a set of free bosonic particles.
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Broer is well-known for having developed the parametrised Kolmogorov-Arnol’d-Moser (KAM) theory. This theory concerns the occurrence of invariant tori in dynamical systems depending on parameters, that carry multi- or quasi-periodic motions. This both goes for the conservative setting — like in celestial mechanics — and for the dissipative setting where families of quasi-periodic tori may form the transitional interface between regular and chaotic dynamics. In the former context he worked on the Laplacian resonance in the motion of the Galilean satellites of Jupiter.
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When moving through air at high speeds, an object's kinetic energy is converted to heat through compression of and friction with the air. At low speeds, the object also loses heat to the air if the air is cooler. The combined temperature effect of heat from the air and from passage through it is called the stagnation temperature; the actual temperature is called the recovery temperature. These viscous dissipative effects to neighboring sub-layers make the boundary layer slow down via a non-isentropic process.
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The total load connected to the power grid can vary significantly over time. Although the total load is the sum of many individual choices of the clients, the overall load is not necessarily stable or slow varying. For example, if a popular television program starts, millions of televisions will start to draw current instantly. Traditionally, to respond to a rapid increase in power consumption, faster than the start-up time of a large generator, some spare generators are put on a dissipative standby mode.
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For a variety of systems, reaction–diffusion equations with more than two components have been proposed, e.g. as models for the regulation of lymphangiogenesis by VEGFC, MMP2, and collagen I; the Belousov–Zhabotinsky reaction, for blood clotting or planar gas discharge systems.H.-G. Purwins et al. in: Dissipative Solitons, Lectures Notes in Physics, Ed. N. Akhmediev and A. Ankiewicz, Springer (2005) It is known that systems with more components allow for a variety of phenomena not possible in systems with one or two components (e.g.
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Transparent conductive coatings are used in applications where it is important that the coating conduct electricity or dissipate static charge. Conductive coatings are used to protect the aperture from electromagnetic Interference, while dissipative coatings are used to prevent the build-up of static electricity. Transparent conductive coatings are also used extensively to provide electrodes in situations where light is required to pass, for example in flat panel display technologies and in many photoelectrochemical experiments. A common substance used in transparent conductive coatings is indium tin oxide (ITO).
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Special products that require additives include: ultra-violet protection, anti-static, flame retardant, custom colors, corrosive inhibitors, static-dissipative, among others. This material is commonly used to erect commercial, political or other types of signs and for constructing plastic containers and reusable packaging. It is widely used in the signwriting industry for making signs for real estate sales, construction sites and promotions. The last decade has found its increasing use among guinea pig, rabbit, domesticated hedgehog and other small pet enthusiasts as components of DIY cages.
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As computers and electronics become ever more pervasive in consumer products an increasing number of manufacturers will need to apply anti-static control measures. One such measure is antistatic apparel because people are the greatest source of static charge in the workplace. Transportation of electrostatic sensitive devices also requires packaging that provides protection from electrostatic hazards in the transportation or storage system. In the case of an ESD protected area designed with continuous grounding of all conductors and dissipative items (including personnel), packaging may not be necessary.
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In mathematics, a conservative system is a dynamical system which stands in contrast to a dissipative system. Roughly speaking, such systems have no friction or other mechanism to dissipate the dynamics, and thus, their phase space does not shrink over time. Precisely speaking, they are those dynamical systems that have a null wandering set: under time evolution, no portion of the phase space ever "wanders away", never to be returned to or revisited. Alternately, conservative systems are those to which the Poincaré recurrence theorem applies.
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This coupling results in an electric body force in the bulk liquid, outside the electric double layer, that can generate temporal, convective, and absolute flow instabilities. Electrokinetic flows with conductivity gradients become unstable when the electroviscous stretching and folding of conductivity interfaces grows faster than the dissipative effect of molecular diffusion. Since these flows are characterized by low velocities and small length scales, the Reynolds number is below 0.01 and the flow is laminar. The onset of instability in these flows is best described as an electric "Rayleigh number".
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There are two conspicuous dissipative effects: rolling friction when the coin slips along the surface, and air drag from the resistance of air. Experiments show that rolling friction is mainly responsible for the dissipation and behavior—experiments in a vacuum show that the absence of air affects behavior only slightly, while the behavior (precession rate) depends systematically on coefficient of friction. In the limit of small angle (i.e. immediately before the disk stops spinning), air drag (specifically, viscous dissipation) is the dominant factor, but prior to this end stage, rolling friction is the dominant effect.
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Impedance matching structures invariably take on the form of a filter, that is, a network of non-dissipative elements. For instance, in a passive electronics implementation, it would likely take the form of a ladder topology of inductors and capacitors. The design of matching networks shares much in common with filters and the design invariably will have a filtering action as an incidental consequence. Although the prime purpose of a matching network is not to filter, it is often the case that both functions are combined in the same circuit.
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The rotational direction of E. coli is controlled by the flagellar motor switch. A ring of 34 FliM proteins around the rotor bind CheY, whose phosphorylation state determines whether the motor rotates in a clockwise or counterclockwise manner. The rapid switching mechanism is attributed to an ultrasensitive response, which has a Hill coefficient of ~10. This system has been proposed to follow a dissipative allosteric model, in which rotational switching is a result of both CheY binding and energy consumption from the proton motive force, which also powers the flagellar rotation.
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Traditionally, a fixed stock paradigm has been applied, but Tilton and Lagos (2007)Tilton, J. & Lagos, G. (2007) "Assessing the long-run availability of copper." Resources Policy, 32, 19–23 suggest using an opportunity cost paradigm is better because the usable resource quantity is represented by price and the opportunity cost of using the resource. Unlike energy minerals such as coal or oil – or minerals used in a dissipative or metabolic fashion like phosphorusCordell, D., Drangert, J.-O. & White, S. (2009) "The story of phosphorus: Global food security and food for thought".
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An infalling observer will see the point of entry of the information as being localized on the event horizon, while an external observer will notice the information being spread out uniformly over the entire stretched horizon before being re- radiated. To an infalling observer, information and entropy pass through the horizon with nothing strange happening. To an external observer, the information and entropy is absorbed into the stretched horizon which acts like a dissipative fluid with entropy, viscosity and electrical conductivity. See the membrane paradigm for more details.
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In physics, an oscillon is a soliton-like phenomenon that occurs in granular and other dissipative media. Oscillons in granular media result from vertically vibrating a plate with a layer of uniform particles placed freely on top. When the sinusoidal vibrations are of the correct amplitude and frequency and the layer of sufficient thickness, a localized wave, referred to as an oscillon, can be formed by locally disturbing the particles. This meta- stable state will remain for a long time (many hundreds of thousands of oscillations) in the absence of further perturbation.
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In the context of quantum computation, it represents a qubit coupled to an environment, which can produce decoherence. In the study of amorphous solids, it provides the basis of the standard theory to describe their thermodynamic properties. The dissipative two-level system represents also a paradigm in the study of quantum phase transitions. For a critical value of the coupling to the bath it shows a phase transition from a regime in which the particle is delocalized among the two positions to another in which it is localized in only one of them.
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Motivated by one of authors systematic study of dissipative Landau-Zener transition, the key idea was demonstrated earlier by a group of scientists from China, Greece and USA in 2000, as steering an eigenstate to destination. Counterdiabatic driving has been demonstrated in the laboratory using a time- dependent quantum oscillator. The use of counterdiabatic driving requires to diagonalize the system Hamiltonian, limiting its use in many-particle systems. In the control of trapped quantum fluids, the use of symmetries such as scale invariance and the associated conserved quantities has allowed to circumvent this requirement.
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In manufacturing, prevention of ESD is based on an Electrostatic Discharge Protected Area (EPA). The EPA can be a small workstation or a large manufacturing area. The main principle of an EPA is that there are no highly-charging materials in the vicinity of ESD sensitive electronics, all conductive and dissipative materials are grounded, workers are grounded, and charge build-up on ESD sensitive electronics is prevented. International standards are used to define a typical EPA and can be found for example from International Electrotechnical Commission (IEC) or American National Standards Institute (ANSI).
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It omits the analysis of subjective phenomena, and it overemphasizes concrete Q-analysis (correlation of objects) to the virtual exclusion of R-analysis (correlation of variables). By asserting that societies (ranging from totipotential communities to nation- states and non-supranational systems) have greater control over their subsystem components than supranational systems have, it dodges the issue of transnational power over the contemporary social systems. Miller's supranational system bears no resemblance to the modern world-system that Immanuel Wallerstein (1974) described, although both of them were looking at the same living (dissipative) structure.
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Generally, longer attenuators with thicker baffles will have a greater insertion loss over a wider frequency range. These types of attenuators are commonly used on air handling units, ducted fan coil units, and at the air intake of compressors, gas turbines, and other ventilated equipment enclosures.. On certain air handling unit or fan applications, it is common to use a co-planar silencer -- a dissipative silencer that is sized for the fan and mounted directly to the fan outlet. This is a common feature in fan array design.
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The use of nano-PTFE in fluoroelastomers and perfluoroelastomers improves abrasion resistance, lowers friction, lowers permeation, and can act as clean filler. Using conductive carbon black or other fillers can exhibit the useful properties of conductive rubber, namely preventing electrical arcing, static sparks, and the overall build-up of charge within rubber that may cause it to behave like a capacitor (electrostatic dissipative). By dissipating these charges, these materials, which include doped carbon-black and rubber with metal filling additives, reduce the risk of ignition, which can be useful for fuel lines.
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Living organisms must obey the laws of thermodynamics, which describe the transfer of heat and work. The second law of thermodynamics states that in any closed system, the amount of entropy (disorder) cannot decrease. Although living organisms' amazing complexity appears to contradict this law, life is possible as all organisms are open systems that exchange matter and energy with their surroundings. Thus living systems are not in equilibrium, but instead are dissipative systems that maintain their state of high complexity by causing a larger increase in the entropy of their environments.
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Sir Anthony James Leggett (born 26 March 1938) is a theoretical physicist and professor emeritus at the University of Illinois at Urbana-Champaign. Leggett is widely recognised as a world leader in the theory of low-temperature physics, and his pioneering work on superfluidity was recognised by the 2003 Nobel Prize in Physics. He has shaped the theoretical understanding of normal and superfluid helium liquids and strongly coupled superfluids. He set directions for research in the quantum physics of macroscopic dissipative systems and use of condensed systems to test the foundations of quantum mechanics.
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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. 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. 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.
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Dissipative particle dynamics (DPD) is a stochastic simulation technique for simulating the dynamic and rheological properties of simple and complex fluids. It was initially devised by Hoogerbrugge and Koelman to avoid the lattice artifacts of the so-called lattice gas automata and to tackle hydrodynamic time and space scales beyond those available with molecular dynamics (MD). It was subsequently reformulated and slightly modified by P. Español to ensure the proper thermal equilibrium state. A series of new DPD algorithms with reduced computational complexity and better control of transport properties are presented.
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The algorithms presented in this article choose randomly a pair particle for applying DPD thermostating thus reducing the computational complexity. DPD is an off-lattice mesoscopic simulation technique which involves a set of particles moving in continuous space and discrete time. Particles represent whole molecules or fluid regions, rather than single atoms, and atomistic details are not considered relevant to the processes addressed. The particles' internal degrees of freedom are integrated out and replaced by simplified pairwise dissipative and random forces, so as to conserve momentum locally and ensure correct hydrodynamic behaviour.
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In amplifying faint signals, it is often necessary to minimize electronic noise, particularly in the first stage of amplification. As a dissipative element, even an ideal resistor naturally produces a randomly fluctuating voltage, or noise, across its terminals. This Johnson–Nyquist noise is a fundamental noise source which depends only upon the temperature and resistance of the resistor, and is predicted by the fluctuation–dissipation theorem. Using a larger value of resistance produces a larger voltage noise, whereas a smaller value of resistance generates more current noise, at a given temperature.
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In mathematics, inertial manifolds are concerned with the long term behavior of the solutions of dissipative dynamical systems. Inertial manifolds are finite-dimensional, smooth, invariant manifolds that contain the global attractor and attract all solutions exponentially quickly. Since an inertial manifold is finite-dimensional even if the original system is infinite- dimensional, and because most of the dynamics for the system takes place on the inertial manifold, studying the dynamics on an inertial manifold produces a considerable simplification in the study of the dynamics of the original system.R. Temam.
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5 He was one of the founders of the physics laboratory of ENS-Lyon, initiating there the study of various research fields, such as dissipative structures generated by instability,O. Thual and S. Fauve, « Localized structures generated by subcritical instabilities », J. Physique, 49, (1988), p. 1829 granular media,S. Douady, S. Fauve and C. Laroche, « Subharmonic instabilities and defects in a granular layer under vertical vibrations », Europhysics Letters, 8, (1989), p. 621C. Coste, E. Falcon and S. Fauve, « Solitary waves in a chain of beads in Hertzian contact », Phys. Rev.
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During this time, Boris Kerner together with V.V. Osipov developed a theory of Autosolitons - solitary intrinsic states, which form in a broad class of physical, chemical and biological dissipative systems. After emigration from Russia to Germany in 1992, Boris Kerner worked for the Daimler company in Stuttgart. His major interest since then was the understanding of vehicular traffic. The empirical nucleation nature of traffic breakdown at highway bottlenecks understood by Boris Kerner is the basis for Kerner's three phase traffic theory, which he introduced and developed in 1996–2002.
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On reflective beaches, incident waves and subharmonic edge waves are dominant. In highly dissipative surf zones, shoreward decay of incident waves is accompanied by shoreward growth of infragravity energy; in the inner surf zone, currents associated with infragravity standing waves dominate. On intermediate states with pronounced bar-trough (straight or crescentic) topographies, incident wave orbital velocities are generally dominant but significant roles are also played by subharmonic and infragravity standing waves, longshore currents, and rips. The strongest rips and associated feeder currents occur in association with intermediate transverse bar and rip topographies.
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Fang was born on 28 February 1935 in Shanghai, Republic of China, with his ancestral home in Dinghai, Zhejiang. He graduated from the Department of Physics of Beijing Normal University in 1956, and researched and taught nuclear physics afterwards. In the 1970s, he studied at the Université Libre de Bruxelles in Belgium under the Nobel Prize laureate Ilya Prigogine, and earned his Ph.D. in 1980. After returning to China, he introduced Prigogine's dissipative system theory to China, and established the study of systems theory at Beijing Normal University.
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Let A be a linear operator defined on a linear subspace D(A) of the reflexive Banach space X. Then A generates a contraction semigroup if and only ifEngel and Nagel Corollary II.3.20 # A is dissipative, and # A − λ0I is surjective for some λ0> 0, where I denotes the identity operator. Note that the conditions that D(A) is dense and that A is closed are dropped in comparison to the non-reflexive case. This is because in the reflexive case they follow from the other two conditions.
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Her simulation algorithms address the limitations of the Schrödinger equation, which can only describe physical changes exactly in the quantum state of small molecules. By identifying aspects of simulations which can be effectively simplified, Dr. Makri's group have developed "the first fully quantum mechanical methodology for calculating the evolution of a quantum system in a dissipative environment by performing an iterative decomposition of Feynman’s path integral expression". Such simplifications make it possible to calculate outcomes that otherwise would not be mathematically feasible. Her careful examinations of the system- harmonic bath model have resulted in techniques for avoiding the Monte Carlo sign problem.
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A spinning/rolling disk ultimately comes to rest quite abruptly, the final stage of motion being accompanied by a whirring sound of rapidly increasing frequency. As the disk rolls, the point of rolling contact describes a circle that oscillates with a constant angular velocity \omega. If the motion is non-dissipative (frictionless), \omega is constant, and the motion persists forever; this is contrary to observation, since \omega is not constant in real life situations. In fact, the precession rate of the axis of symmetry approaches a finite-time singularity modeled by a power law with exponent approximately −1/3 (depending on specific conditions).
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Valerii Vinokur (also spelled as Vinokour, or Valery Vinokour, born 26 April 1949) is a condensed matter physicist who works on superconductivity, the physics of vortices, disordered media and glasses, nonequilibrium physics of dissipative systems, quantum phase transitions, quantum thermodynamics, and topological quantum matter. He is a Senior Scientist and Argonne Distinguished Fellow at Argonne National Laboratory and a Senior Scientist at the Consortium for Advanced Science and Engineering, Office of Research and National Laboratories, The University of Chicago. He is a Foreign Member of the National Norwegian Academy of Science and Letters and a Fellow of the American Physical Society.
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Surveys indicate that 90% of open clusters dissolve less than 1 billion years after formation, while only a tiny fraction survive for the present age of the Solar System (about 4.6 billion years). Over the next few hundred million years, the Hyades will continue to lose both mass and membership as its brightest stars evolve off the main sequence and its dimmest stars evaporate out of the cluster halo. It may eventually be reduced to a remnant containing about a dozen star systems, most of them binary or multiple, which will remain vulnerable to ongoing dissipative forces.
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At various points, the intermediate product is exported to the cytosol for additional transformations and then re-imported. Three specific pyruvate cycles are generally considered, each named for the principal molecule exported from the mitochondrion: malate, citrate, and isocitrate. Other variants may exist, such as dissipative or "futile" pyruvate cycles. This cycle is usually studied in relation to Glucose Stimulated Insulin Secretion ( or GSIS ) and there is thought to be a relationship between the insulin response and NADPH produced from this cycle but the specifics are not clear and particular confusion exists about the role of malic enzymes.
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In the standard model of AGN, cold material close to a black hole forms an accretion disc. Dissipative processes in the accretion disc transport matter inwards and angular momentum outwards, while causing the accretion disc to heat up. The expected spectrum of an accretion disc peaks in the optical- ultraviolet waveband; in addition, a corona of hot material forms above the accretion disc and can inverse-Compton scatter photons up to X-ray energies. The radiation from the accretion disc excites cold atomic material close to the black hole and this in turn radiates at particular emission lines.
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Kopnin's primary research area was superconductivity, in particular non-equilibrium and non- stationary phenomena. One of the forces acting on quantum vortices in superfluids and superconductors is known as the "Kopnin force" after him. In 1991, by extending his theory concerning this force to chiral superfluids, he predicted the existence of fermionic bound states, quasiparticles now known as Majorana fermions and that it may be possible to observe in topological superfluids and superconductors. He contributed to the studies of anisotropic and layered superconductors and developed the microscopic theories for dissipative and non-stationary flow in Fermi superfluids.
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The cross-flow fan uses an impeller with forward-curved blades, placed in a housing consisting of a rear wall and a vortex wall. Unlike radial machines, the main flow moves transversely across the impeller, passing the blading twice. The flow within a cross-flow fan may be broken up into three distinct regions: a vortex region near the fan discharge, called an eccentric vortex, the through-flow region, and a paddling region directly opposite. Both the vortex and paddling regions are dissipative, and as a result, only a portion of the impeller imparts usable work on the flow.
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The dissipative two- level system is a particular realization of the Caldeira–Leggett model that deserves special attention due to its interest in the field of quantum computation. The aim of the model is to study the effects of dissipation in the dynamics of a particle that can hop between two different positions rather a continuous degree of freedom. This reduced Hilbert space allows the problem to be described in terms of ½-spin operators. This is sometimes referred in the literature as the spin-boson model, and it is closely related to the Jaynes–Cummings model.
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The trousers have nine pockets: two thigh pockets; two calf pockets with external tool pockets; one knife pocket with lanyard (on the left thigh); and two side hanging pockets. Pockets (except for the side hanging pockets and the lower leg external tool pockets) have flaps and zippers. The A2CU upgrades the current Improved Aviation Battle Dress Uniform protective clothing system and provides operational effectiveness, fit, suitability, and durability, addressing near-term Air Warrior requirements in the universal camouflage pattern. The A2CU is made of a blend of 92 percent Nomex, 5 percent Kevlar, and 3 percent anti-static dissipative fiber.
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As with any hysteretic process, the area inside the magnetization curve during one cycle represents the work that is performed on the material by the external field in reversing the magnetization, and is dissipated as heat. Common dissipative processes in magnetic materials include magnetostriction and domain wall motion. The coercivity is a measure of the degree of magnetic hysteresis and therefore characterizes the lossiness of soft magnetic materials for their common applications. The squareness (saturation remanence divided by saturation magnetization) and coercivity are figures of merit for hard magnets although energy product (saturation magnetization times coercivity) is most commonly quoted.
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As quantum mechanics, and any classical dynamical system, relies heavily on Hamiltonian mechanics for which 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 equation.
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There seems to be agreement that life is a manifestation of non-equilibrium thermodynamics, both as to individual living creatures and as to aggregates of such creatures, or ecosystems. See e.g. Brooks and WylieEvolution as Entropy, Brooks and Wylie, University of Chicago press, p 103 et seq Smolin,Smolin, Ch. 11 What is Life Chaisson, Stuart KauffmanInvestigations, Stuart Kauffman, Oxford University Press 2000 and "Origins of Order", Oxford, 1993 and Ulanowicz.Ecology, the Ascendent Perspective, Robert Ulanowicz, Columbia Univ. Press 1997 This realization has proceeded from, among other sources, a seminal concept of ‘dissipative systems’ offered by Ilya Prigogine.
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The uniqueness of work in this scheme is considered to guarantee rigor and purity of conception. The conceptual purity of this definition, based on the concept of energy transferred as work as an ideal notion, relies on the idea that some frictionless and otherwise non-dissipative processes of energy transfer can be realized in physical actuality. The second law of thermodynamics, on the other hand, assures us that such processes are not found in nature. Before the rigorous mathematical definition of heat based on Carathéodory's 1909 paper, historically, heat, temperature, and thermal equilibrium were presented in thermodynamics textbooks as jointly primitive notions.
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Shortly after François Jacob and Jacques Monod developed their first model of gene regulation, Goodwin proposed the first model of a genetic oscillator, showing that regulatory interactions among genes allowed periodic fluctuations to occur. Shortly after this model became published, he also formulated a general theory of complex gene regulatory networks using statistical mechanics. In its simplest form, Goodwin's oscillator involves a single gene that represses itself. Goodwin equations were originally formulated in terms of conservative (Hamiltonian) systems, thus not taking into account dissipative effects that are required in a realistic approach to regulatory phenomena in biology.
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The Chaplygin sleigh is a simple pedagogical example of a nonholonomic system in mechanics, described by Sergey Chaplygin. It consists of a body that slides frictionlessly on a horizontal plane, with a knife edge that constrains its motion so that the knife slides only longitudinally. Because this constraint is nonholonomic, Liouville's theorem does not apply, and although energy is conserved, the motion is dissipative in the sense that phase-space volume is not conserved. The motion is attracted to an equilibrium, in which the sleigh moves without rotation, with the knife edge trailing the center of mass.
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His post-doctoral work resulted in the development of the Josephson Bifurcation Amplifier, which makes use of the non-dissipative, non-linear nature of the Josephson junction to realize high gain and minimal back action measurements of quantum systems. He joined the University of California, Berkeley as a faculty member in the summer of 2005, and is currently a full professor in the Physics Department. In 2015, his laboratory was awarded the UC Berkeley Award for Excellence in Laboratory Safety, awarded by the Berkeley Office of Environment, Health and Safety. Siddiqi's research is mainly focused on the fields of quantum electrodynamics and cQED.
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Doppler cooling was simultaneously proposed by two groups in 1975, the first being David J. Wineland and Hans Georg Dehmelt and the second being Theodor W. Hänsch and Arthur Leonard Schawlow. It was first demonstrated by Wineland, Drullinger, and Walls in 1978 and shortly afterwards by Neuhauser, Hohenstatt, Toschek and Dehmelt. One conceptually simple form of Doppler cooling is referred to as optical molasses, since the dissipative optical force resembles the viscous drag on a body moving through molasses. Steven Chu, Claude Cohen-Tannoudji and William D. Phillips were awarded the 1997 Nobel Prize in Physics for their work in laser cooling and atom trapping.
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In fracture mechanics, the energy release rate, G, is the rate at which energy is transformed as a material undergoes fracture. Mathematically, the energy release rate is expressed as the decrease in total potential energy per increase in fracture surface area, and is thus expressed in terms of energy per unit area. Various energy balances can be constructed relating the energy released during fracture to the energy of the resulting new surface, as well as other dissipative processes such as plasticity and heat generation. The energy release rate is central to the field of fracture mechanics when solving problems and estimating material properties related to fracture and fatigue.
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Moffatt's theoretical work inspired several other workers to experimentally investigate the dissipative mechanism of a spinning/rolling disk, with results that partially contradicted his explanation. These experiments used spinning objects and surfaces of various geometries (disks and rings), with varying coefficients of friction, both in air and in a vacuum, and used instrumentation such as high speed photography to quantify the phenomenon. In the 30 November 2000 issue of Nature, physicists Van den Engh, Nelson and Roach discuss experiments in which disks were spun in a vacuum. Van den Engh used a rijksdaalder, a Dutch coin, whose magnetic properties allowed it to be spun at a precisely determined rate.
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Table I in The effects of nuclear spin bath and heat bath coupling on the Landau–Zener process were explored by Sinitsyn and Prokof'ev and Pokrovsky and Sun, respectively. Exact results in multistate Landau–Zener theory (no-go theorem and BE-formula) can be applied to Landau-Zener systems which are coupled to baths composed of infinite many oscillators and/or spin baths (dissipative Landau-Zener transitions). They provide exact expressions for transition probabilities averaged over final bath states if the evolution begins from the ground state at zero temperature, see in Ref. for oscillator baths and for universal results including spin baths in Ref.
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Kraus is best known for her work in quantum information and especially in entanglement theory. Together with her coworkers she developed criteria to decide whether a quantum state is separable or entangled and showed how to construct optimal entanglement witnesses and studied the creation of entanglement by unitary quantum gates and dissipative processes. In 2010 she showed how to decide whether two pure quantum states of a many- particle system are equivalent to each other in terms of entanglement. More recently she introduced the notion of "maximally entangled sets" as a new concept generalizing maximally entangled states to the case of considering entanglement between more than two systems (multipartite entanglement).
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In 1951 Callen and Welton proved the quantum fluctuation-dissipation theorem (FDT) which was originally formulated in classical form by Nyquist (1928) as an explanation for observed Johnson noise in electric circuits. Fluctuation-dissipation theorem showed that when something dissipates energy, in an effectively irreversible way, a connected heat bath must also fluctuate. The fluctuations and the dissipation go hand in hand; it is impossible to have one without the other. The implication of FDT being that the vacuum could be treated as a heat bath coupled to a dissipative force and as such energy could, in part, be extracted from the vacuum for potentially useful work.
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Gregory Lawrence Eyink is an American mathematical physicist at Johns Hopkins University. He received his bachelor’s degree in mathematics and philosophy (1981) and Doctor of Philosophy (1987) from Ohio State University. He now holds joint appointments in the departments of Physics and Astronomy, Mathematics, and Mechanical Engineering at Johns Hopkins. He was awarded the status of Fellow of the American Physical Society , after being nominated by their Topical Group on Statistical and Nonlinear Physics in 2003, for his work in nonequilibrium statistical mechanics, in particular on the foundation of transport laws in chaotic dynamical systems, on field-theoretic methods in statistical hydrodynamics and on singularities and dissipative anomalies in fluid turbulence.
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Russian-Belgian physical chemist Ilya Prigogine, who coined the term dissipative structure, received the Nobel Prize in Chemistry in 1977 for his pioneering work on these structures, which 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. 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.
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In non-equilibrium physics, the Keldysh formalism is a general framework for describing the quantum mechanical evolution of a system in a non-equilibrium state or systems subject to time varying external fields (electrical field, magnetic field etc.). Historically, it was foreshadowed by the work of Schwinger and proposed almost simultaneously by Keldysh and, separately, Kadanoff and Baym. It was further developed by later contributors such as O. V. Konstantinov and V. I. Perel. Extension to driven-dissipative open quantum systems is given in The Keldysh formalism provides a systematic way to study non-equilibrium systems, usually based on the two-point functions corresponding to excitations in the system.
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For example, a chemical reaction at constant temperature and pressure will reach equilibrium at a minimum of its components' Gibbs free energy and a maximum of their entropy. Equilibrium thermodynamics differs from non-equilibrium thermodynamics, in that, with the latter, the state of the system under investigation will typically not be uniform but will vary locally in those as energy, entropy, and temperature distributions as gradients are imposed by dissipative thermodynamic fluxes. In equilibrium thermodynamics, by contrast, the state of the system will be considered uniform throughout, defined macroscopically by such quantities as temperature, pressure, or volume. Systems are studied in terms of change from one equilibrium state to another; such a change is called a thermodynamic process.
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1–2, the transition by temporal Intermittency, which was confirmed by numerous experimental observations and CFD simulations. This is the so-called Pomeau–Manneville scenario, associated with the Pomeau- Manneville maps Pomeau, Y.; Manneville, P. (1980). "Intermittent Transition to Turbulence in Dissipative Dynamical Systems". Commun. Math. Phys. 74 (2): 189–197 In papers published in 1973 and 1976, Hardy, Pomeau and de Pazzis Hardy, J., Pomeau, Y., and De Pazzis, O. «Time evolution of a two-dimensional classical lattice system.» Physical Review Letters 31.5 (1973): 276.. Hardy, J., De Pazzis, O. , and Pomeau, Y. « Molecular dynamics of a classical lattice gas: Transport properties and time correlation functions.» Physical review A 13.5 (1976): 1949.
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A holon is a system (or phenomenon) that is an evolving self-organizing dissipative structure, composed of other holons, whose structures exist at a balance point between chaos and order. It is sometimes discussed in the context of self- organizing holarchic open systems (or, SOHO systems). For full details, see: A holon is maintained by the throughput of matter–energy and information–entropy connected to other holons and is simultaneously a whole in itself and at the same time is nested within another holon and so is a part of something much larger than itself. Holons range in size from the smallest subatomic particles and strings, all the way up to the multiverse, comprising many universes.
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The formalism is well suited to arbitrary choices of coordinates, known in the context as generalized coordinates. The kinetic and potential energies of the system are expressed using these generalized coordinates or momenta, and the equations of motion can be readily set up, thus analytical mechanics allows numerous mechanical problems to be solved with greater efficiency than fully vectorial methods. It does not always work for non-conservative forces or dissipative forces like friction, in which case one may revert to Newtonian mechanics. Two dominant branches of analytical mechanics are Lagrangian mechanics (using generalized coordinates and corresponding generalized velocities in configuration space) and Hamiltonian mechanics (using coordinates and corresponding momenta in phase space).
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In 1919, he discovered the Barkhausen effect (named after him), which provided evidence for the magnetic domain theory of ferromagnetism. When the magnetic field through a piece of ferromagnetic material like iron is changing, the magnetization of the material changes in a series of tiny discontinuous jumps, which can be heard as a series of clicks in a loudspeaker attached to a coil of wire around the iron. It was later determined that these jumps were caused by the movement of the magnetic domains in the iron, as the domain walls snap past defects in the crystal lattice. The energy lost in these dissipative events is responsible for the shape of the hysteresis curve of iron and other ferromagnets.
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Pinning force is a force acting on a pinned object from a pinning center. In solid state physics, this most often refers to the vortex pinning, the pinning of the magnetic vortices (magnetic flux quanta, Abrikosov vortices) by different kinds of the defects in a type II superconductor. Important quantities are the individual maximal pinning force, which defines the depinning of a single vortex, and an average pinning force, which defines the depinning of the correlated vortex structures and can be associated with the critical current density (the maximal density of non-dissipative current). The interaction of the correlated vortex lattice with system of pinning centers forms the magnetic phase diagram of the vortex matter in superconductors.
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In quantum physics an anomaly or quantum anomaly is the failure of a symmetry of a theory's classical action to be a symmetry of any regularization of the full quantum theory. In classical physics, a classical anomaly is the failure of a symmetry to be restored in the limit in which the symmetry-breaking parameter goes to zero. Perhaps the first known anomaly was the dissipative anomaly in turbulence: time-reversibility remains broken (and energy dissipation rate finite) at the limit of vanishing viscosity. Technically, an anomalous symmetry in a quantum theory is a symmetry of the action, but not of the measure, and so not of the partition function as a whole.
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The neo-Hookean model does not account for the dissipative release of energy as heat while straining the material and perfect elasticity is assumed at all stages of deformation. The neo-Hookean model is based on the statistical thermodynamics of cross-linked polymer chains and is usable for plastics and rubber-like substances. Cross-linked polymers will act in a neo-Hookean manner because initially the polymer chains can move relative to each other when a stress is applied. However, at a certain point the polymer chains will be stretched to the maximum point that the covalent cross links will allow, and this will cause a dramatic increase in the elastic modulus of the material.
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Chiral magnetic effect (CME) is the generation of electric current along an external magnetic field induced by chirality imbalance. The CME is a macroscopic quantum phenomenon present in systems with charged chiral fermions, such as the quark-gluon plasma, or Dirac and Weyl semimetals; for review, see. The CME is a consequence of chiral anomaly in quantum field theory; unlike conventional superconductivity or superfluidity, it does not require a spontaneous symmetry breaking. The chiral magnetic current is non- dissipative, because it is topologically protected: the imbalance between the densities of left- and right-handed chiral fermions is linked to the topology of fields in gauge theory by the Atiyah-Singer index theorem.
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Since 2011, Hess developed the theory of optical activity in chiral nanoplasmonic metamaterials that provided explanation of experiments on tunability in self-organised gold metamaterials. Recently Hess has started to develop "meta-lasers" and proposed "stopped-light nanolasing". This exploits and unites his competence in nanoplasmonic metamaterials, quantum photonics and semiconductor lasers. Initially the motivation for the work was to compensate dissipative losses in metamaterials by introducing gain. But now, one aims at realising a new class of ultrafast ‘stopped-light nanolasers’, with unprecedented design features such as being smaller than a fifth of the wavelength and ultrafast and providing a platform to integrate both light and amplified plasmons, to enable integration at the nanoscale with semiconductor chips for telecommunications.
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Gomatam’s primary area of research is in non-relativistic quantum mechanics (QM), which emerged in 1925 with Erwin Schrödinger's derivation of the "wave equation". Gomatam is developing his own approach to macroscopic quantum mechanics (MQM, applying the wave equation to the macroscopic regime), which is distinct from the ideas of ‘macroscopic dissipative systems’ and ‘macroscopic quantum coherence’, developed in the early 80s by Anthony James Leggett. In general, Leggett's attempt is to indirectly observe superposition at the macroscopic level by extending current microscopic quantum physics to the macroscopic level. In contrast, Gomatam is attempting to develop MQM independent of the application of the Schrödinger equation to the micro regime, in such a manner that quantum superposition can be directly observed at the macroscopic level.
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It has been argued by some that all emergent order in the universe from galaxies, solar systems, planets, weather, complex chemistry, evolutionary biology to even consciousness, technology and civilizations are themselves examples of thermodynamic dissipative systems; nature having naturally selected these structures to accelerate entropy flow within the universe to an ever-increasing degree. For example, it has been estimated that human body is 10,000 times more effective at dissipating energy per unit of mass than the sun. One may query what this has to do with zero-point energy. Given the complex and adaptive behaviour that arises from nonlinear systems considerable attention in recent years has gone into studying a new class of phase transitions which occur at absolute zero temperature.
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Pugh An Improved Closing Lemma and a General Density Theorem, American Journal of Mathematics, Band 89, 1967, S.1010–1021, "Closing Lemma" by Christian Bonatti in Scholarpedia The lemma states: Let f be a diffeomorphism of a compact manifold with a nonwandering point x.Wandering points were introduced by George Birkhoff to describe dissipative systems (with chaotic behavior). In the case of a dynamical system given by a map f, a point wanders if it has a neighborhood U which is disjoint to all of the iterations of the map on it: f^n(U) \cap U = \varnothing.\, Then there is (in the space of diffeomorphisms, equipped with the C^1 topology) in a neighborhood of f a diffeomorphism g for which x is a periodic point.
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Anti-fatigue mats come in various types and materials for industrial or commercial applications for a variety of workplace conditions that exist as well as the variety of workplace designs from individual work benches, to large assembly lines or complex manufacturing work stations. Work place environments can vary from dry areas to wet or extremely oily areas. Plus specialized industries may need additional properties such as fire retardant matting for welding, static dissipative matting for electrostatic discharge (ESD) protection, anti- microbial for food industry applications. Today, this type of ergonomic mat is commonly used during trade shows for floor covering, in hospitals and clinics during surgeries to cover the floor near surgical tables to minimize surgeons fatigue resulted from continuous standing.
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Jantsch's Gauthier Lectures in System Science given in May 1979 at the University of California in Berkeley became the basis for his book The Self- Organizing Universe: Scientific and Human Implications of the Emerging Paradigm of Evolution, published by Pergamon Press in 1980 as part of the System Science and World Order Library edited by Ervin László. The book deals with self-organization as a unifying evolutionary paradigm that incorporates cosmology, biology, sociology, psychology, and consciousness. Jantsch is inspired by and draws on the work of Ilya Prigogine concerning dissipative structures and nonequilibrium states. Now out of print for many years, The Self-organizing Universe has been influential in the interdisciplinary fields of biomimicry, holism, co-evolution, and self-organization.
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At these frequencies a ferromagnetic material such as mild steel is much more effective, due to different and complementary electromagnetic permeability properties, and common practical shielding implementations utilise both an inner high- frequency reflective material such as aluminium, preferably bonded (via annealing or electroplating, done to avoid capacitance between separated layers), to a more substantial structural ferromagnetic shell, usually mild steel (in specialized applications, more expensive, less structurally useful and less workable materials may be preferred.) Despite the relative low mass density of aluminium, this design is usually both lighter and more effective than an equivalently absorptive design utilizing aluminium alone (although with poorer heat dissipative properties, typically accommodated by improved ventilation, which itself needs careful consideration in order to preserve the desired shielding effectiveness).
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The physics of western intensification can be understood through a mechanism that helps maintain the vortex balance along an ocean gyre. Harald Sverdrup was the first one, preceding Henry Stommel, to attempt to explain the mid-ocean vorticity balance by looking at the relationship between surface wind forcings and the mass transport within the upper ocean layer. He assumed a geostrophic interior flow, while neglecting any frictional or viscosity effects and presuming that the circulation vanishes at some depth in the ocean. This prohibited the application of his theory to the western boundary currents, since some form of dissipative effect (bottom Ekman layer) would be later shown to be necessary to predict a closed circulation for an entire ocean basin and to counteract the wind-driven flow.
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"This starting vortex formation occurs not only when a wing is first set into motion, but also when the circulation around the wing is subsequently changed for any reason whatever." Millikan, Clark B., Aerodynamics of the Airplane, page 65 (The strength of a vortex cannot change within the fluid except by the dissipative action of viscosity. Vortices either form continuous loops of constant strength, or they terminate at the boundary of the fluid - usually a solid surface such as the ground.) The starting vortex is significant to an understanding of the Kutta condition and its role in the circulation around any airfoil generating lift. The starting vortex has certain similarities with the "starting plume" which forms at the leading edge of a slug of fluid, when one fluid is injected into another at rest.
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Early sonar transducers had been developed from simplistic design assumptions followed by a trial and error design modification if the transducer failed to meet performance goals. That design approach became impractical for the large number of variables involved in optimized electrical coupling of array elements coupled acoustically by the physics of fluid water. NEL explored transducer theory with tensor analysis and continuum mechanics to determine viscous and hysteretic dissipative effects of transducer materials and radiation impedance of transducers in the water medium. NEL's mathematical models for mutual radiation impedance of transducer elements overwhelmed mechanical calculators and taxed capabilities of contemporary electronic computers. In 1961, the United States and United Kingdom undertook a joint effort to develop digital computer software for analysis and design using the ALGOL-based Navy Electronics Laboratory International Algorithmic Compiler (NELIAC).
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The regular behavior of the Cepheids has been successfully modeled with numerical hydrodynamics since the 1960s, and from a theoretical point of view it is easily understood as due to the presence of center manifold which arises because of the weakly dissipative nature of the dynamical system. This, and the fact that the pulsations are weakly nonlinear, allows a description of the system in terms of amplitude equations and a construction of the bifurcation diagram (see also bifurcation theory) of the possible types of pulsation (or limit cycles), such fundamental mode pulsation, first or second overtone pulsation, or more complicated, double- mode pulsations in which several modes are excited with constant amplitudes. The boundaries of the instability strip where pulsation sets in during the star's evolution correspond to a Hopf bifurcation.
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There is increasing interest in simulating micelles for industrial applications.William C, Jordan, Kirk E, Warren, Patrick B, Noro, Massimo G, Bray, David J, Anderson, Richard L, Toward a standard protocol for micelle simulation, The Journal of Physical Chemistry B, 2016, Vishnyakov, Aleksey, Lee, Ming-Tsung, Neimark, Alexander V, Prediction of the critical micelle concentration of nonionic surfactants by dissipative particle dynamics simulations, The journal of physical chemistry letters 2013, The reliability of some experimental data has been questioned by some authors who have proposed standard data sets.Swope, William C, Johnston, Michael, Andrew, Duff, Andrew Ian, McDonagh, James L, Anderson, Richard L, Alva, Gabriela, Tek, Andy T, Maschino, Alexander P The Challenge to Reconcile Experimental Micellar Properties of the CnEm Nonionic Surfactant Family. The Journal of Physical Chemistry B 2019.
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George Em Karniadakis is a Greek-American researcher, known for his wide- spectrum work on high-dimensional stochastic modeling and multiscale simulations of physical and biological systems. He is one of the pioneers of spectral/hp-element methods for fluids in complex geometries, general Polynomial Chaos for uncertainty quantification, and the theory of Sturm- Liouville theory for fractional partial differential equations. He is currently the Charles Pitts Robinson and John Palmer Barstow Professor of Applied Mathematics at Brown University. He has advised more than forty PhD students in diverse areas of research including numerical methods for computational fluid dynamics, stochastic PDEs, numerical methods for fractional PDEs, modeling uncertainty with polynomial chaos, multiscale modeling of biological systems, dissipative particle dynamics, flow-structure interactions, parallel computing, and interactive/virtual reality computer graphics.
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Dissipative beaches are wide and flat in profile, with a wide shoaling and surf zone, composed of finer sediment, and characterised by spilling breakers. Reflective beaches are steep, and are known for their coarse sand; they have no surf zone, and the waves break brusquely on the intertidal zone. Reflective beaches are typically steep in profile with a narrow shoaling and surf zone, composed of coarse sediment, and characterised by surging breakers. Coarser sediment allows percolation during the swash part of the wave cycle, thus reducing the strength of backwash and allowing material to be deposited in the swash zone Depending on beach state, near bottom currents show variations in the relative dominance of motions due to: incident waves, subharmonic oscillations, infragravity oscillations, and mean longshore and rip currents.
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The behavior of the horizon in this situation is a dissipative system that is closely analogous to that of a conductive stretchy membrane with friction and electrical resistance—the membrane paradigm. This is different from other field theories such as electromagnetism, which do not have any friction or resistivity at the microscopic level, because they are time-reversible. Because a black hole eventually achieves a stable state with only three parameters, there is no way to avoid losing information about the initial conditions: the gravitational and electric fields of a black hole give very little information about what went in. The information that is lost includes every quantity that cannot be measured far away from the black hole horizon, including approximately conserved quantum numbers such as the total baryon number and lepton number.
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Local thermodynamic equilibrium of matter (see also Keizer (1987) means that conceptually, for study and analysis, the system can be spatially and temporally divided into 'cells' or 'micro-phases' of small (infinitesimal) size, in which classical thermodynamical equilibrium conditions for matter are fulfilled to good approximation. These conditions are unfulfilled, for example, in very rarefied gases, in which molecular collisions are infrequent; and in the boundary layers of a star, where radiation is passing energy to space; and for interacting fermions at very low temperature, where dissipative processes become ineffective. When these 'cells' are defined, one admits that matter and energy may pass freely between contiguous 'cells', slowly enough to leave the 'cells' in their respective individual local thermodynamic equilibria with respect to intensive variables. One can think here of two 'relaxation times' separated by order of magnitude.
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In a generalization and thermal variation of the binding change mechanism of today's ATP synthase, the "first protein" would have bound substrates (peptides, phosphate, nucleosides, RNA 'monomers') and condensed them to a reaction product that remained bound until it was released after a temperature change by a thermal unfolding. The primordial first protein would therefore have strongly resembled the beta subunits of the ATP synthase alpha/beta subunits of today's F1 moiety in the FoF1 ATP synthase. Note however that today's enzymes function during isothermal conditions, whereas the hypothetical first protein worked on and during thermal cycling. The energy source under the thermosynthesis hypothesis was thermal cycling, the result of suspension of protocells in a convection current, as is plausible in a volcanic hot spring; the convection accounts for the self-organization and dissipative structure required in any origin of life model.
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A good example of nonlinear electromagnetics is in high energy dense plasmas, where vortical phenomena occur which seemingly violate the second law of thermodynamics by increasing the energy gradient within the electromagnetic field and violate Maxwell's laws by creating ion currents which capture and concentrate their own and surrounding magnetic fields. In particular Lorentz force law, which elaborates Maxwell's equations is violated by these force free vortices. These apparent violations are due to the fact that the traditional conservation laws in classical and quantum electrodynamics (QED) only display linear U(1) symmetry (in particular, by the extended Noether theorem, conservation laws such as the laws of thermodynamics need not always apply to dissipative systems, which are expressed in gauges of higher symmetry). The second law of thermodynamics states that in a closed linear system entropy flow can only be positive (or exactly zero at the end of a cycle).
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It has been suggested, however, that such changes in the surface flux of ultraviolet radiation due to geophysical events affecting the atmosphere could have been what promoted the development of complexity in life based on existing metabolic pathways, for example during the Cambrian explosion Some of the most difficult problems concerning the origin of life, such as enzyme-less replication of RNA and DNA, homochirality of the fundamental molecules, and the origin of information encoding in RNA and DNA, also find an explanation within the same dissipative thermodynamic framework by considering the probable existence of a relation between primordial replication and UV-C photon dissipation. Michaelian suggests that it is erroneous to expect to describe the emergence, proliferation, or even evolution, of life without overwhelming reference to entropy production through the dissipation of a generalized thermodynamic potential, in particular, the prevailing solar photon flux.
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The notion of self-organizing systems is tied with work in nonequilibrium thermodynamics, including that pioneered by chemist and Nobel laureate Ilya Prigogine in his study of dissipative structures. Even older is the work by Hartree-Fock on the quantum chemistry equations and later calculations of the structure of molecules which can be regarded as one of the earliest examples of emergence and emergent wholes in science. One complex system containing humans is the classical political economy of the Scottish Enlightenment, later developed by the Austrian school of economics, which argues that order in market systems is spontaneous (or emergent) in that it is the result of human action, but not the execution of any human design.Friedrich Hayek, "The Results of Human Action but Not of Human Design" in New Studies in Philosophy, Politics, Economics, Chicago: University of Chicago Press, 1978, pp. 96–105.
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A resurgence of interest in classical integrable systems came with the discovery, in the late 1960s, that solitons, which are strongly stable, localized solutions of partial differential equations like the Korteweg–de Vries equation (which describes 1-dimensional non-dissipative fluid dynamics in shallow basins), could be understood by viewing these equations as infinite-dimensional integrable Hamiltonian systems. Their study leads to a very fruitful approach for "integrating" such systems, the inverse scattering transform and more general inverse spectral methods (often reducible to Riemann–Hilbert problems), which generalize local linear methods like Fourier analysis to nonlocal linearization, through the solution of associated integral equations. The basic idea of this method is to introduce a linear operator that is determined by the position in phase space and which evolves under the dynamics of the system in question in such a way that its "spectrum" (in a suitably generalized sense) is invariant under the evolution, cf. Lax pair.
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" With a temperature gradient greater than the minimum, viscosity can dissipate kinetic energy as fast as it is released by convection due to buoyancy, and a steady state with convection is stable. The steady state with convection is often a pattern of macroscopically visible hexagonal cells with convection up or down in the middle or at the 'walls' of each cell, depending on the temperature dependence of the quantities; in the atmosphere under various conditions it seems that either is possible. (Some details are discussed by Lebon, Jou, and Casas-Vásquez (2008) on pages 143–158.) With a temperature gradient less than the minimum, viscosity and heat conduction are so effective that convection cannot keep going. Glansdorff and Prigogine (1971) on page xv wrote "Dissipative structures have a quite different [from equilibrium structures] status: they are formed and maintained through the effect of exchange of energy and matter in non-equilibrium conditions.
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A notable example of a process that is not even quasi-static is the slow heat exchange between two bodies on two finitely different temperatures, where the heat exchange rate is controlled by an approximately adiabatic partition between the two bodies-- in this case, no matter how slowly the process takes place, the states of the composite system consisting of the two bodies is far from equilibrium, since thermal equilibrium for this composite system requires that the two bodies be at the same temperature. Some ambiguity exists in the literature concerning the distinction between quasi-static and reversible processes, as these are sometimes taken as synonyms. The reason is the theorem that any reversible process is also a quasi-static one, even though (as we have illustrated above) the converse is not true. In practical situations, it is essential to differentiate between the two: any engineer would remember to include friction when calculating the dissipative entropy generation, so there are no reversible processes in practice.
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Schumann resonances are the principal background in the part of the electromagnetic spectrum from 3 Hz through 60 Hz, and appear as distinct peaks at extremely low frequencies (ELF) around 7.83 Hz (fundamental), Department of Theoretical and Experimental Nuclear Physics, Odessa National Polytechnic University, Ukraine 14.3, 20.8, 27.3 and 33.8 Hz. In the normal mode descriptions of Schumann resonances, the fundamental mode is a standing wave in the Earth–ionosphere cavity with a wavelength equal to the circumference of the Earth. This lowest-frequency (and highest-intensity) mode of the Schumann resonance occurs at a frequency of approximately 4.11 Hz, but this frequency can vary slightly from a variety of factors, such as solar-induced perturbations to the ionosphere, which compresses the upper wall of the closed cavity. The higher resonance modes are spaced at approximately 6.5 Hz intervals, a characteristic attributed to the atmosphere's spherical geometry. The peaks exhibit a spectral width of approximately 20% on account of the damping of the respective modes in the dissipative cavity.
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Anchored to this nucleus are a group of trunks wired in steel which keep the external strips in traction where the latticed structures of the attics are located, which compress themselves towards the nucleus and collaborates with the overall static system. The wind pressure is minimized by the helix shape made by the trunks in the skyscraper, described by the three sails made by the overlapping of the habitable floors which revolve around the central trunk creating in planimetry a growing movement based on the golden spiral. The form reacts to the action of the wind, whatever direction it comes from, in a uniform and dissipative way. The result is the elimination of two of the main negative phenomena vis-à-vis the typology of skyscrapers: the excess static caused by the asymmetry of traditional structures of rectangular design, where the pressure of the wind is highest on the long side and lowest on the short one and the Von Karman effect typical of cylindrical structures which provokes a sinusoidal whirlwind and consequently lateral pulsating forces.
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They do not loosen the knot related to the intricate relationships between invariance and morphogenesis and do not arise in relation to the actual realization of a specific embodiment. Hence the importance of making reference to theoretical tools more complex and variegated as, for instance, non-standard mathematics and complexity theory, in order to provide an adequate basis for the afore mentioned exploration. As Carsetti shows in 2012 in his volume Epistemic Complexity and Knowledge Construction, by referring to this particular and very simple theoretical “landscape”, it is possible to realize that the constraints imposed by specific selective pressures (operating in ambient meaning and articulating in accordance with suitable non-standard procedures) at the level of the dynamics of an original cellular (dissipative) automaton can, actually, permit a more complex canalization of the informational fluxes at stake. In particular, they can allow the unfolding of silent potentialities, the full expression of generative principles never before revealed and, consequently, the effective expression of new autonomous processes of production of varied complexity.
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