Transport by weak electrostatic density drift fluctuations

1983 ◽  
Vol 30 (1) ◽  
pp. 153-168
Author(s):  
J. J. Sanderson ◽  
S. Peter Gary
Keyword(s):  
Magnetic Field ◽  
Free Energy ◽  
Steady State ◽  
Uniform Magnetic Field ◽  
Distribution Functions ◽  
Lower Hybrid ◽  
Steady State Distribution ◽  
State Distribution ◽  
Particle Exchange ◽  
Vlasov Plasma

Expressions are derived for transport by weak electrostatic microfluctuations driven unstable by a density gradient perpendicular to a uniform magnetic field in a Vlasov plasma. These expressions, which are evaluated for the universal and lower-hybrid density drift instabilities, provide improved physical interpretations for various wave-particle exchange frequencies previously reported. It is demonstrated that wave-particle effects generally reduce the free energy driving these instabilities, and that some forms of steady-state distribution functions are inappropriate for nonlinear theory.

The Diffusion and Thermalization of an Electron Cloud Injected into an Afterglow Plasma

1971 ◽  
Vol 49 (9) ◽  
pp. 1124-1136
Author(s):  
H. W. H. Van Andel
Keyword(s):  
Magnetic Field ◽  
Distribution Function ◽  
Steady State ◽  
Boltzmann Equation ◽  
Axial Magnetic Field ◽  
Electron Cloud ◽  
Steady State Distribution ◽  
State Distribution ◽  
Account Electron ◽  
Afterglow Plasma

The steady state distribution function for a suprathermal electron cloud injected into a cylindrical plasma is found as a function of position and velocity by solving the Boltzmann equation numerically in the Fokker–Planck approximation with an added term taking into account electron-neutral collisions. The injection is assumed to take place at one end of the cylinder, and an axial magnetic field is assumed present. A number of representative solutions are given for various choices of the parameters of the problem.

Kinetic analysis of mechanism of intestinal Na+-dependent sugar transport

1985 ◽  
Vol 248 (5) ◽  
pp. C498-C509 ◽  
Author(s):  
D. Restrepo ◽  
G. A. Kimmich
Keyword(s):  
Experimental Data ◽  
Steady State ◽  
Sugar Transport ◽  
Enzyme Kinetic ◽  
Steady State Distribution ◽  
State Distribution ◽  
Least Squares Fit ◽  
Coupling Stoichiometry ◽  
Rate Limiting ◽  
Kinetics Of

Zero-trans kinetics of Na+-sugar cotransport were investigated. Sugar influx was measured at various sodium and sugar concentrations in K+-loaded cells treated with rotenone and valinomycin. Sugar influx follows Michaelis-Menten kinetics as a function of sugar concentration but not as a function of Na+ concentration. Nine models with 1:1 or 2:1 sodium:sugar stoichiometry were considered. The flux equations for these models were solved assuming steady-state distribution of carrier forms and that translocation across the membrane is rate limiting. Classical enzyme kinetic methods and a least-squares fit of flux equations to the experimental data were used to assess the fit of the different models. Four models can be discarded on this basis. Of the remaining models, we discard two on the basis of the trans sodium dependence and the coupling stoichiometry [G. A. Kimmich and J. Randles, Am. J. Physiol. 247 (Cell Physiol. 16): C74-C82, 1984]. The remaining models are terter ordered mechanisms with sodium debinding first at the trans side. If transfer across the membrane is rate limiting, the binding order can be determined to be sodium:sugar:sodium.

PROCESSOR SHARING G-QUEUES WITH INERT CUSTOMERS AND CATASTROPHES: A MODEL FOR SERVER AGING AND REJUVENATION

2017 ◽  
Vol 31 (4) ◽  
pp. 420-435 ◽  
Author(s):  
J.-M. Fourneau ◽  
Y. Ait El Majhoub
Keyword(s):  
Steady State ◽  
Product Form ◽  
Processor Sharing ◽  
Service Capacity ◽  
Steady State Distribution ◽  
State Distribution ◽  
Signal Arrival ◽  
Open Networks ◽  
Networks Of Queues

We consider open networks of queues with Processor-Sharing discipline and signals. The signals deletes all the customers present in the queues and vanish instantaneously. The customers may be usual customers or inert customers. Inert customers do not receive service but the servers still try to share the service capacity between all the customers (inert or usual). Thus a part of the service capacity is wasted. We prove that such a model has a product-form steady-state distribution when the signal arrival rates are positive.

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