A METHOD FOR CONVERGENCE ACCELERATION IN PSEUDO-TRANSIENT INTEGRATION OF DIFFUSION EQUATION SYSTEMS

The method presented in the paper ensures consistent convergence acceleration for the so- lution of the diffusion problem in electromagnetic field by finite difference and the pseudo- transient methods of integration of the partial differential equation system, providing it is a priori known that the solution is periodical. The effectiveness of the method is illustrated in the numerical results of an actual problem

Tandori Dezső pályakezdése folyóiratokban és antológiákban

Tandori Dezső első két kötete, a Töredék Hamletnek és az Egy talált tárgy megtisztí‐ tása a magyar irodalom egyik legmeghatározóbb életművének kezdőpontjaként híres. Ugyanakkor a két kötetnek természetszerűleg vannak előzményei: a versek újságokban, folyóiratokban, antológiákban jelentek meg már a kötetek előtt. A tíz éves felkészülési periódus az aktuális kultúrpolitika, valamint a könyvkiadók kockázatkerülő magatartása miatt természetesnek tekinthető abban a korban, mégis meglepő, hisz Tandorinak már az első verseit figyelem övezte. Az első kötet előzményeit vizsgálva megállapítható, hogy Tandori ezt az időszakot alapos ter‐ vezéssel töltötte: nemcsak a versszövegeket gondozta, hanem kötetbeli sorrendjü‐ ket is kijelölte. E munka nyomait a folyóirat‐közlések is magukon viselik, de to‐ vábbi kérdésekhez is vezetnek: mennyit változott a koncepció a mitikus, soha meg nem jelent Egyetlen című kötethez képest? Tandori második kötetének előzményei eltérő képet festenek. A szövegeket, úgy tűnik, röpke két év alatt írta, de a kötet csak öt évvel az első után jelent meg. Szemben a Töredékkel, a Talált tárgy nem „darabokban” került a közönség elé, ha‐ nem két nagy részletben a vajdasági Híd című folyóiratban, a versek sorrendje pedig még csak nyomokban sem emlékeztetett a későbbi kötetre. Ez a két eltérő modell nemcsak a kötetek keletkezési körülményeibe enged mélyebb betekintést, hanem az alkotói módszerek különbözőségébe is. Dezső Tandori’s first two books, Töredék Hamletnek [A Fragment for Hamlet] and Egy talált tárgy megtisztítása [Cleansing of an Object Lost and Found] are still widely celebrated as the starting point of one of the most important careers in Hungarian literature. But the two books necessarily go back to antecedents: his poems had been published in journals, periodicals and in an anthology ten years prior to his books. This long delay, while it was normal in the 1960’s mainly because of the cultural politics of Hungary and of the risk‐avoiding nature of book publishers, is still surprising since already the first poems of Tandori were received with uni‐ versal praise. But further examination reveals that Tandori spent those ten years meticulously planning his first book, preparing not only the poems but also their sequence, that is, the main structure of the book. This structure is already laid out in the publications in journals, the order of the poems rarely changed later. This leads to another question: how much did the book diverge from the legendary, never published Egyetlen [Only One]? We know from interviews and recollections that the book was only allowed to be published in a mutilated form, but interest‐ ingly, we cannot find the extra poems supposed to be in this version of the book. The antecedents to his second book, Egy talált tárgy megtisztítása indicate a dif‐ ferent process. Allegedly written in the time‐span of mere two years, it got pub‐ lished five years after his first book. While the samples of Töredék Hamletnek were published in several small dosages, parts of the second book were published in two big collections, both in the same journal ‘Híd’ [Bridge], and the order of the poems does not even resemble their final arrangement in the book. The different publication models allow us to see deeper into the creation and construction of the books, and also into the different creative methods of the author

EDDY CURRENTS IN FERROMAGNETIC SHEETS TAKING MAGNETIC HYSTERESIS NONLINEARITIES INTO ACCOUNT

The paper deals with the numerical solution of the diffusion problem getting for the time varying electromagnetic field in ferromagnetic and conductive media. It presents a method based on the scalar Preisach model describing local magnetic behaviour of material (the static hysteresis characteristic) and on the pseudo-transient method for integration of the partial differential equation system formulated by finite difference. It enables simulation of dynamic operation demanding experimental data obtained by static measurements only. Numerical results are presented for different frequencies and wave forms of the source field applied at the surface of a ferromagnetic sheet

Preisach Type Hysteresis Models with Everett Function in Closed Form

The Preisach function is considered as a product of two special one dimensional functions, which allows the closed form evaluation of the Everett integral. The deduced closed form expression is included in static and rate dependent hysteresis models. The applicability and accuracy of the models are discussed and demonstrated fitting measured data. The developed hysteresis models, which are freely available for research and educational purpose, proved to be fast enough to be incorporated in electromagnetic software

Flow-based Capacity Allocation in the CEE Electricity Market: Sensitivity Analysis, Multiple Optima, Total Revenue

The paper introduces the mechanism of the Flow-based Capacity Allocation (FBA) method on the electricity market of the Central-Eastern Europe (CEE) Region, proposed by the Central Allocation Office (CAO). The method is a coordinated heterogeneous multi-unit uniform price auction where the allocation is determined by the solution of a linear programming problem. On one hand, the properties of the underlying linear programming problem are discussed: the possibilities of multiple solutions are analysed, then a non-standard sensitivity analysis method of the market spread auction is developed. On the other hand, a global optimization problem is presented that yields uniform auction prices corresponding to higher total income than at the original allocation method. Several numerical examples and results of practical test problems are presented