# Szemináriumok

## Harmonikus metrikák és aszimptotikus viselkedésük

Időpont:
2017. 10. 17. 10:30
Hely:
H.306
Szabó Szilárd

## Regular Decomposition: an information and graph theoretic approach to stochastic block models

Időpont:
2017. 10. 12. 16:15
Hely:
H306
Ilkka Norros (VTT Technical Research Centre of Finland)

## Harmonikus metrikák és spinorok aszimptotikus viselkedése

Időpont:
2017. 10. 12. 14:00
Hely:
T604
Szabó Szilárd (BME Matematika Intézet)

## On the zero-stability of multistep methods on smooth nonuniform grids

Időpont:
2017. 10. 12. 10:15
Hely:
H306
Imre Fekete (Eötvös Loránd University & MTA-ELTE NUMNET)

In order to be convergent, linear multistep methods must be zero stable. While constant step size theory was established in the 1950’s, zero stability on nonuniform grids is less well understood. Here we investigate zero stability on compact intervals and smooth nonuniform grids. The grid points are constructed as the image of an equidistant grid under a smooth deformation map. We show that for all strongly stable linear multistep methods, there is an $N^*$ such that a condition of zero stability is always fulfilled for $N > N^*$ under a smoothness condition. Examples are given for Adams and BDF type methods.

## Finding patterns in Brownian motion

Időpont:
2017. 10. 05. 16:15
Hely:
H306
Hermann Thorisson (University of Iceland)

## Egy trace-egyenlőtlenség két bizonyítása

Időpont:
2017. 10. 05. 14:00
Hely:
T604
Vrana Péter (BME Matematika Intézet)

## An explicit analytic solution of a coupled first order partial and ordinary differential equation system for a discontinuous initial-boundary value problem

Időpont:
2017. 10. 05. 10:15
Hely:
H306
Zachár András

Non-polynomial series solution of a coupled first order partial and ordinary differential equation (PDE-ODE) system for a discontinuous initial and boundary condition has been developed. Linear equation systems are constructed to calculate the constant coefficients of the series solution. Explicit expressions have been found to the solution of these linear equation systems. Different forms of the solution have been compared to the numerical solution of the PDE-ODE system and the rate of the convergence is also investigated. The studied first order PDE-ODE system describes an unsteady convection dominated heat transfer process induced by a buoyant plume entrainment.

## Error Exponents for Random Access Models and the Capacity Region of Partly Asynchronous Multiple Access Channel

Időpont:
2017. 10. 03. 12:15
Hely:
H306