Kramers Equation
Mostrando 1-5 de 5 artigos, teses e dissertações.
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1. Solução exata da equação de Kramers para uma partícula Browniana carregada sob ação de campos elétrico e magnético externos e aplicações à hidrotermodinâmica / Exact solution of Kramers equation for a charged Brownian particle under the action of external electric and magnetic fields and applications to the hydrothermodynamics
Após apresentarmos uma revisão dos principais modelos teóricos para o movimento Browniano, consideramos em particular o caso de uma partícula Browniana carregada sob ação de campos elétrico e magnético. A obtenção de uma solução analítica para este caso, resolvendo a equação de Kramers para a distribuição de probabilidades de uma partícula
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 10/12/2010
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2. Simulations of plasmas with electrostatic PIC models using the finite element method
Particle-in-cell (PIC) methods allow the study of plasma behavior by computing the trajectories of finite-size particles under the action of external and self-consistent electric and magnetic fields defined in a grid of points. In this work, the Finite Element Method (FEM) is used in order to obtain the self-consistent fields. An electrostatic PIC-FEM comput
Brazilian Journal of Physics. Publicado em: 2003-06
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3. Fractal ladder models and power law wave equations
The ultrasonic attenuation coefficient in mammalian tissue is approximated by a frequency-dependent power law for frequencies less than 100 MHz. To describe this power law behavior in soft tissue, a hierarchical fractal network model is proposed. The viscoelastic and self-similar properties of tissue are captured by a constitutive equation based on a lumped
Acoustical Society of America.
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4. Measuring Solution Viscosity and its Effect on Enzyme Activity
In proteins, some processes require conformational changes involving structural domain diffusion. Among these processes are protein folding, unfolding and enzyme catalysis. During catalysis some enzymes undergo large conformational changes as they progress through the catalytic cycle. According to Kramers theory, solvent viscosity results in friction against
Biological Procedures Online.
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5. Spontaneous action potentials due to channel fluctuations.
A theoretical and numerical analysis of the Hodgkin-Huxley equations with the inclusion of stochastic channel dynamics is presented. It is shown that the system can be approximated by a one-dimensional bistable Langevin equation. Spontaneous action potentials can arise from the channel fluctuations and are analogous to escape by a particle over a potential b