Results 271 to 280 of about 11,801 (293)

Optimal filtering for degenerate nonlinear diffusions

Proceedings of the 38th IEEE Conference on Decision and Control (Cat. No.99CH36304), 2003
The optimal filtering problem for a nonlinear stochastic system with a non-elliptic diffusion term is studied. Under a more general geometric assumption involving the system reachability, (which includes the strong elliptic case), a Zakai-like equation is derived, and the existence and unicity of the solution is proved.
CARRAVETTA F. ., GERMANI, Alfredo, MANES, COSTANZO   +2 more
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Diffusion-weighted imaging in Wallerian degeneration

Journal of the Neurological Sciences, 2000
We report two patients displaying hyperintensities on diffusion-weighted imaging (DWI) in the area of Wallerian degeneration (WD) at 12 days after stroke. High signal intensities were more conspicuous on DWI than on T2-weighted images. Both patients showed decreased diffusion anisotropy resulting in elevated apparent diffusion coefficient in the area ...
D W, Kang, K, Chu, B W, Yoon, I C, Song, K H, Chang, J K, Roh   +5 more
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Degenerate Diffusion Processes

2020
In this chapter, we show that the degenerate points may separate the state space into different regions for multiple classes, and we discuss the optimization of multi-class degenerate diffusion processes. We also show that under some conditions, the performance function of finite-horizon optimization problems, or the potential function of the long-run ...
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Degenerate Nonlinear Diffusion Equations

2012
The aim of this notes is to include in a unitary presentation some topics related to the theory of degenerate nonlinear diffusion equations, treated in the mathematical framework of evolution equations with multivalued maximal monotone operators in Hilbert spaces.
FAVINI, ANGELO, G. Marinoschi
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Infantile Diffuse Cerebral Degeneration With Hepatic Cirrhosis

Archives of Neurology, 1976
Four children had progressive degeneration of the cerebral cortex, with hepatic cirrhosis. They and four previously described ones, are representative of a distinct form of hepatocerebral degeneration. Onset of the neurological disorder is between ages 1 and 3 years, at times with mild developmental delay.
P R, Huttenlocher, G B, Solitare, G, Adams   +2 more
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Existence for Diffusion Degenerate Problems

2012
In this chapter we present another method for studying the well-posedness of a multivalued degenerate fast diffusion equation by proposing an appropriate time discretization scheme. We consider that the degeneration of the equation is due to the vanishing of the diffusion coefficient and choose for this problem Robin boundary conditions which contain ...
Angelo Favini, Gabriela Marinoschi
openaire   +1 more source

Degenerate Diffusions with regular Hamiltonians

AIP Conference Proceedings, 2005
We consider the asymptotic behaviour for small time and small parameter of the heat kernel on the cotangent bundle of a Riemannian manifold defined by a stochastically perturbed geodesic flow generalizing WKB‐type methods to a diffusion corresponding to a particular regular degenerate Hamiltonian.
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Numerical simulation for degenerate diffusions

Applied Numerical Mathematics, 1990
The author considers special finite difference schemes for singular degenerate parabolic equations describing stochastic diffusion processes. The main attention is given to the following problem connected with the statistical description of the wave propagation in random media: (1) \(y_ t=(1-\rho^ 2)^ 2y_{\rho \rho}-[(1-\rho^ 2)(1+7\rho^ 2)\rho^{-1 ...
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Delayed Diffusion Restriction of Wallerian Degeneration

Neurocritical Care, 2023
Daniel J. Zhou, Daryl R. Gress, Maximiliano A. Hawkes   +2 more
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Diffuse Muscular Degeneration in Captive Harbor Seals

Journal of the American Veterinary Medical Association, 1972
SUMMARY Three juvenile harbor seals in captivity for 2 months developed an illness manifested as anorexia, reluctance to move, and an arched posture. Necropsy revealed diffuse muscular degeneration characterized by swollen, hyalinized, fragmented fibers. The cause of the muscle degeneration was not determined.
openaire   +2 more sources