Space-Time Discontinuous Galerkin Methods for Weak Solutions of Hyperbolic Linear Symmetric Friedrichs Systems

We study weak solutions and its approximation of hyperbolic linear symmetric Friedrichs systems describing acoustic, elastic, or electro-magnetic waves. For the corresponding first-order systems we construct discontinuous Galerkin discretizations in space and time with full upwind, and we show primal and dual consistency. Stability and convergence estimates are provided with respect to a mesh-dependent DG norm which includes the L$_2$ norm at final time. Numerical experiments confirm that the a priori results are of optimal order also for solutions with low regularity, and we show that the error in the DG norm can be closely approximated with a residual-type error indicator

Space-time discontinuous Galerkin discretizations for linear first-order hyperbolic evolution systems. Revised March 2016

We introduce a space-time discretization for linear first-order hyperbolic evolution systems using a discontinuous Galerkin approximation in space and a Petrov-Galerkin scheme in time. We show well-posedness and convergence of the discrete system. Then we introduce an adaptive strategy based on goal-oriented dual-weighted error estimation. The full space-time linear system is solved with a parallel multilevel preconditioner. Numerical experiments for the linear transport equation and the Maxwell equation in 2D underline the effciency of the overall adaptive solution process

Space-time discontinuous Galerkin methods for weak solutions of hyperbolic linear symmetric Friedrichs systems

We study weak solutions and its approximation of hyperbolic linear symmetric Friedrichs systems describing acoustic, elastic, or electro-magnetic waves. For the corresponding first-order systems we construct discontinuous Galerkin discretizations in space and time with full upwind, and we show primal and dual consistency. Stability and convergence estimates are provided with respect to a mesh-dependent DG norm which includes the $L_2$ norm at final time. Numerical experiments confirm that the a piori results are of optimal order also for solutions with low regularity, and we show that the error in the DG norm can be closely approximated with a residual-type error indicator

Parallel space-time solutions for the linear visco-acoustic and visco-elastic wave equation

We present parallel adaptive results for a discontinuous Galerkin space-time discretization for acoustic and elastic waves with attenuation. The method is based on $p$-adaptive polynomial discontinuous ansatz and test spaces and a first-order formulation with full upwind fluxes. Adaptivity is controlled by dual-primal error estimation, and the full linear system is solved by a Krylov method with space-time multilevel preconditioning. The discretization and solution method is introduced in Dörfler-Findeisen-Wieners (Comput. Meth. Appl. Math. 2016) for general linear hyperbolic systems and applied to acoustic and elastic waves in Dörfler-Findeisen-Wieners-Ziegler (Radon Series Comp. Appl. Math. 2019); attenuation effects were included in Ziegler (PhD thesis 2019, Karlsruhe Institute of Technology). Here, we consider the evaluation of this method for a benchmark configuration in geophysics, where the convergence is tested with respect to seismograms. We consider the scaling on parallel machines and we show that the adaptive method based on goal-oriented error estimation is able to reduce the computational effort substantially

Space-time discontinuous Galerkin discretizations for linear first-order hyperbolic evolution systems

We introduce a space-time discretization for linear first-order hyperbolic evolution systems using a discontinuous Galerkin approximation in space and a Petrov-Galerkin scheme in time. We show well-posedness and convergence of the discrete system. Then we introduce an adaptive strategy based on goal-oriented dual-weighted error estimation. The full space-time linear system is solved with a parallel multilevel preconditioner. Numerical experiments for the linear transport equation and the Maxwell equation in 2D underline the effciency of the overall adaptive solution process

BUDUĆNOST AUSTRIJSKOG TURIZMA

Die Tourismuswirtschaft ist für Österreichs Volkswirtschaft von großer Bedeutung. Anders, als in anderen Industrieländern, leben in Österreich große Teile der Bevölkerung vom Tourismus direkt oder sind indirekt von der Entwicklung des Tourismus betroffen. Nach einer Aussendung der Österreichwerbung (ÖW) sind in Österreich 500.000 Menschen in ihrer Erwerbstätigkeit vom Tourismus abhängig. 1996 betrugen die Tourismuseinnahmen It. Österreichischer Nationalbank ÖS 148,3 Mrd. Die kleingewerbliche betriebliche Struktur Österreichs bietet zwar viele Vorteile, ist fü r den Auftritt am globalen Markt jedoch wenig geeignet. Wir können jedoch durch effiziente Kooperationen zwischen Unternehmern oder ganzer Talschaften Abhilfe schaffen. Aufgrund der vielen natürlichen Vorteile der österreichischen Tourismuswirtschaft bestehen auch in Zukunft für innovative Unternehmer sehr gute Chancen am Weltmarkt.Turistička privreda je za austrijsko gospodarstvo od velikog značaja. Za razliku od mnogih drugih industrijskih zemalja, u Austriji živi velik dio stanovništva od turizma, te je direktno ili indirektno zavisno od turizma. Prema nekim podacima u Austriji 500.000 zaposlenih zavisi od turizma. U 1996 godini iznosili su prihodi od turizma 148,3 Mrd. ATS. U strukturi austrijskih turističkih poduzeća prevladavaju uglavnom mala poduzeća, što pruža mnogo prednosti, ali je za pristup na globalno turističko tržište ipak nepovoljno. No, putem efikasnih kooperacija između poduzeća moguće je postići određene rezultate. Temeljem mnogih prirodnih prednosti austrijske turističke privrede postoje za inovativna poduzeća dobre prilike za pristup na svjetsko tržište također u budućnosti

M.I.C.E. - SUCCESS FACTORS AND OPPORTUNITIES

Die MICEwirtschaft (Meeting, Incentive, Convention, Event) nimmt in Europa einen bedeutenden Stellenwert in der Ertragslage der Hotelindustrie ein. Mit den vielfachen Tagesausgaben im Vergleich zu Feriengästen sind die Tagungsgäste aber auch die Liebkinder von Regionalmanagern. Eine immer größer werdende Anzahl von Unternehmen versucht auf diesem Markt Fuß zu fassen, vom Seminarhotel bis hin zur Eventagentur. In diesem Beitrag wird der Versuch einer einheitlichen Begriffsdefinition der unterschiedlichen Veranstaltungstypen unternommen. Weiters wird punktuell auf die Marktsituation am europäischen und österreichischen Markt mit Aspekten für die kroatische Tourismusindustrie eingegangen.MICE ekonomija (Meeting /sastanak/, Incentive /podstrek/, Convention /kongres/, Event /zbivanje/) zauzima u Europi značajno i vrijedno mjesto u prihodima hotelske industrije. S mnogobrojnim dnevnim izdacima u usporedbi s gostima koji su na odmoru sudionoici kongresa također su miljenici i regionalnih menadžera. Sve veći broj poduzeća od hotela za seminare do agencija za organiziranje raznih zbivanja pokušava na tom tržištu učvrstiti poziciju. U ovom se radu pokušava iznaći sveobuhvatna pojmovna definicija za sve različite vrste zbivanja i događanja. Također se detaljno obrađuje tržišna situacija na europskom i austrijskom tržištu sa aspektima povezanim za hrvatsku turističku industriju.M.I.C.E economy (Meeting, Incentive, Convention, Event) in Europe plays an important role in the earnings of the hotel industries. Convention guests are favorites of regional managers, as their daily spending greatly exceeds that of holiday guests. A growing number of enterprises, ranging from convention hotels to various event agencies, are striving to gain a footing in this market. This paper seeks to provide a comprehensive conceptual definition for the various types of events. It also provides a detailed analysis of the situation of the European and Austrian markets with regard to the Croatian tourist industry

Qualitätsmanagement u turizmu

"Gäste beschweren sich nicht, sie kommen einfach nicht mehr". Dienstleistungsqualität und Qualitätsmanagement sind daher die wichtigsten Aspekte für die zukünftige europäische Tourismusentwicklung, sei es für eine Region oder den einzelnen Betrieb. Voraussetzung um Qualitätsmanagement zu implementieren, ist die genaue Kenntnis der unternehmensspezifischen Prozesse und das Messen der Kundenzufriedenheit z.B. durch Gästebefragungen. Die Erlebniswelt des Gastes muß in ihrer Gesamtheit - vom telefonischem Erstkontakt bis hin zum Aus-Checken - Beachtung finden. Daraus resultieren auch neue Aufgaben für Führungskräfte. Gefordert sind - neben Sachkompetenz - auch soziale Kompetenz, persönliche Kompetenz und Kompetenz für Methoden. Die ISO 9000-Normenreihe ist ein Versuch Qualitätsmanagement in Betrieben anhand von Checklisten zu implementieren. Seriöse Beratung ist aber bei der Installierung von Qualitätsmanagementsystemen in jedem Fall zu empfehlen."Gosti se ne žale, oni jednostavno više ne dođu." Kvaliteta usluga i kvaliteta managementa najvažniji su aspekti budućeg europskog razvoja turizma, kako za regiju tako i za pojedino poduzeće. Pretpostavka za implementiranje kvalitetnog managementa je dobro poznavanje specifičnih procesa u poduzeću kao i mjerenje zadovoljstva gostiju, primjerice putem anketa. Treba voditi računa o cjelokupnom dojmu koji na gosta ostavlja hotel: od prvog telefonskog kontakta do odlaska iz hotela, što za rukovodeći kadar predstavlja novi izazov. Traži se, osim stručne kompetencije, i socijalna kompetentnost, osobna kompetentnost, kao i kompetentnost metoda. ISO 9000 pokušaj je uvođenja kvalitetnog managementa u poduzeće na osnovi "Checkslita". Međutim, u svakom slučaju se preporuča savjet stručnjaka kod uvođenja sustava Qualitatsmanagementa

Parallel adaptive discontinuous Galerkin discretizations in space and time for linear elastic and acousticwaves

We introduce a space-time discretization for elastic and acoustic waves using a discontinuous Galerkin approximation in space and a Petrov–Galerkin scheme in time. For the dG method, the upwind flux is evaluated by explicitly solving a Riemann problem. Then we show well-posedness and convergence of the discrete system. Based on goal-oriented dualweighted error estimation an adaptive strategy is introduced. The full space-time linear system is solved with a parallel multilevel preconditioner. Numerical experiments for acoustic and elastic waves underline the efficiency of the overall adaptive solution process

Perspectives for unfolding well-being in the context of teacher education. Emerging well-being insights from theoretical Austrian traditions

This article focuses on teacher education and aims to gain new and different insights into teacher education with reference to wellbeing. The Austrian contribution initially introduces the project team and the understanding of well-being from a specific tradition, which has particularly evolved through the project over time. It highlights the importance of well-being and the diversity of its interpretations, aiming to link this approach with several Austrian traditions of thought. It also seems theoretically not insignificant how the word ‘wellbeing’ or ‘wellbeing’ is spelt. To emphasize the connection to teacher education, the concept of well-being is associated with the Didactic Triangle of Johann Friedrich Herbart (1776–1841) and interwoven across and through Austrian traditions of thinking. Some exemplary excerpts from focus groups illustrate the theoretical considerations presented in this paper. The article suggests that future research should particularly contemplate the directedness of one’s exegesis – because when considering Austrian traditions of thought, a careful unpacking of the meaning is required. Particularly in the application of the idea and concept in relation to teacher education. (DIPF/Orig.