A new combination of techniques for the numerical computation of incompressible flow is presented. The temporal discretization bases on the discontinuous Galerkin-formulation. Both constant (DG(0)) and linear approximation (DG(1)) in time is discussed. In case of DG(1) an iterative method reduces the problem to a sequence of problems each with the dimension of the DG(0) approach. For the semi-discrete problems a Galerkin/least-squares method is applied. Furthermore a non-overlapping domain decomposition method can be used for a parallelized computation. The main advantage of this approach is the low amount of information which must be exchanged between the subdomains. Due to the slight bandwidth a workstation-cluster is a suitable platform. Otherwise this method is efficient only for a small number of subdomains. The interface condition is of the Robin/Robin-type and for the Navier-Stokes equation a formulation introducing a further pressure interface condition is used. Additionally a suggestion for the implementation of the standard k-epsilon turbulence model with special wall function is done in this context. All the features mentioned above are implemented in a code called ParallelNS. Using this code the verification of this approach was done on a large number of examples ranging from simple advection-diffusion problems to turbulent convection in a closed cavity.

Sverige rör sig mot ett kontantlöst samhälle i en takt som uppmärksammas internationellt. Det svenska betalningsväsendet kan komma att genomgå omfattande strukturella förändringar inom snar framtid. En av dessa förändringar kan antas vara införandet av den digitala centralbanksvalutan (CBDC) e-kronan. Då språnget mot det kontantlösa samhället börjat uttrycka sig i resten av världen är olika länders centralbanker mitt uppe i att reda ut de makroekonomiska effekter som en CBDC medför. Då e-kronan är ett nytt fenomen existerar det inte någon omfattande empirisk forskning, utan förhållandesättet är fortfarande teoretiskt. Vi undersöker därför de makroekonomiska effekter som kan tänkas uppstå vid införandet av en räntebärande e-krona från kort till lång sikt, samt diskuterar möjligheten för att använda e-kronan som ett penningpolitiskt styrmedel. Vi finner utifrån en modifiering av IS-MP-PC-modellen att en räntebärande e-krona som sätts i enlighet med inflationsmålet har liknande makroekonomiska effekter som styrräntan har idag. Vidare utvidgar vi en överlappande generationsmodell och visar på en undanträngning av reala tillgångar på lång sikt vid höga räntenivåer på e-kronan relativt till räntan på reala tillgångar i ett intergenerationellt sammanhang. / Sweden is moving towards a cashless society at an internationally recognized pace. The Swedish payment system may undergo extensive structural changes in the near future. One of these changes is assumed to be the introduction of the digital central bank currency (CBDC) e-krona. As the leap towards a cashless society has begun to manifest itself in the rest of the world, various countries' central banks are in the midst of figuring out the macroeconomic effects that a CBDC brings. As the e-krona is a new phenomenon, there is no extensive empirical research and the approach is still theoretical. We therefore investigate the macroeconomic effects that may arise from the introduction of an interest-bearing e-krona from the short to the long term and discuss the possibility of using the e-krona as a monetary policy instrument. By modifying the IS-MP-PC-model we find that an interest-bearing e-krona set in accordance with the inflation target has similar macroeconomic effects as the policy rate today. Furthermore, we extend an overlapping generations model and show a crowding out effect of real assets in the long run when the interest rate on the e-krona is high relative to the interest rate on real assets in an intergenerational context.

Rozsáhlá třída inženýrských optimalizačních úloh vede na modely s omezeními ve tvaru obyčejných nebo parciálních diferenciálních rovnic (ODR nebo PDR). Protože diferenciálních rovnice je možné řešit analyticky jen v nejjednodušších případech, bylo k řešení použito numerických metod založených na diskretizaci oblasti. Zvolili jsme metodu konečných prvků, která umožňuje převod omezení ve tvaru diferenciálních rovnic na omezení ve tvaru soustavy lineárních rovnic. Reálné problémy jsou často velmi rozsáhlé a přesahují dostupnou výpočetní kapacitu. Výpočetní čas lze snížit pomocí progressive hedging algoritmu (PHA), který umožňuje paralelní implementaci. PHA je efektivní scénářová dekompoziční metoda pro řešení scénářových stochastických úloh. Modifikovaný PHA byl využit pro původní přístup prostorové dekompozice. Aproximace diferenciálních rovnic v modelu problému je dosaženo pomocí diskretizace oblasti. Diskretizace je dále využita pro prostorovou dekompozici modelu. Algoritmus prostorové dekompozice se skládá z několika hlavních kroků: vyřešení problému s hrubou diskretizací, rozdělení oblasti problému do překrývajících se částí a iterační řešení pomocí PHA s jemnější diskretizací s využitím hodnot z hrubé diskretizace jako okrajových podmínek. Prostorová dekompozice byla aplikována na základní testovací problém z oboru stavebního inženýrství, který se zabývá návrhem rozměrů průřezu nosníku. Algoritmus byl implementován v softwaru GAMS. Získané výsledky jsou zhodnoceny vzhledem k výpočetní náročnosti a délce překrytí.

Continuous fibre-reinforced thermoplastics often are offered as impregnated and consolidated semi-finished products which are known as organic sheets. The thermoplastic matrix leads to several advantages including the thermoformability and weldability. Parts made of organic sheets are frequently produced by forming the semi-finished product into half-shells and stiffening those shells in the course of the process e.g. by the injection moulding of ribs. Larger and more complex parts with hollow body structures can be manufactured e.g. by forming the semi-finished products into half-shells and joining the half-shells. However, the currently available manufacturing technologies for parts made of organic sheets have cap profile shaped joints which prevent the use of the reinforcing fibres across the joint plane. Investigations have proven that overlapping weld joints in organic sheets show much higher strengths than cap profile shaped joints which can be explained by the fibre use across the joint plane. Furthermore, the infrared welding technology was verified as an appropriate process for the welding of organic sheets since no need for additional welding material is given, short heating times can be realized and no contact of the infrared emitters to the joining parts is required. Therefore, the present study shall reveal the high potential of the overlapping welding of organic sheets. Influences on the weld strengths of infrared welded organic sheets are described and potential improvements concerning the materials to be welded as well as the welding process are shown.

Endlosfaserverstärkte Thermoplaste werden oftmals als imprägnierte und konsolidierte Halbzeuge angeboten. Solche thermoplastischen Prepregs werden üblicherweise als Organobleche bezeichnet. Die thermoplastische Matrix ermöglicht unter anderem die Warmformbarkeit und Schweißbarkeit von Organoblechen. Organobleche sind, durch die ausschließliche Möglichkeit sie mittels Thermoformen umzuformen, in ihrer Formgebung auf halbschalige Strukturen beschränkt, welche begrenzte Torsions-, Verwindungs- und Beulsteifigkeiten aufweisen. Um die Steifigkeiten dieser schalenförmigen, offenen Bauteile zu erhöhen, können z. B. versteifende Rippen oder Verstärkungssegmente eingebracht werden. Aufgrund des Thermoformprozesses sind mit Organoblechen, verglichen mit duroplastischen Systemen, jedoch nur kleine und einfache Bauteilgeometrien realisierbar. Um neben der Steifigkeitserhöhung auch größere und komplexere Bauteile herzustellen, können die schalenförmigen Organobleche während des Umformvorgangs gefügt werden. Auf diese Weise werden Hohlkörper in Doppelhutprofilform gefertigt. So werden, auch ohne Einbringung von Rippen o. ä., hohe Bauteilsteifigkeiten erreicht. Die Doppelhutprofilform hat jedoch eine nicht optimale Nutzung der Faserverstärkung über die Fügeebene hinweg zur Folge, da die Fasern von der Belastungsrichtung abweichend umgelenkt werden. Im vorliegenden Beitrag wird daher das überlappende Infrarotschweißen von Organoblechen behandelt, was eine Faserverstärkung über die Fügeebene hinweg ermöglicht. Die Prozess- und Werkstoffeinflüsse auf die Verbindungseigenschaften werden beschrieben und Möglichkeiten zur Optimierung der Schweißnahteigenschaften dargestellt. Des Weiteren werden Optimierungskriterien für überlappende Infrarotschweißungen an den untersuchten Organoblechen festgelegt. Die im Verlauf der Forschungsarbeiten umzusetzenden Verfahrensvarianten zur Herstellung von Hohlkörperbauteilen aus Organblechen werden zudem vorgestellt.

Thermoplastic prepregs that are also known as organo sheets are processed in presses and formed to half shells. Larger components can be produced by joining the half shells, which results in hollow bodies. However, current manufacturing technologies allow only cap profile shaped joints, which cause fiber deflections in the joint plane. This presentation shows that overlapping infrared welds in organo sheets enable weld strengths close to the interlaminar shear strengths of the unwelded materials and thus a fiber utilization across the joint plane. By using high welding pressures, a matrix depletion and a change of the fiber alignment in the weld plane may occur which causes low weld strengths. Therefore possibilbites to optimize the weld strengths are shown and one possible process variants for the manufacturing of hollow bodies by infrared welding is introduced.

Thermoplastic prepregs that are also known as organo sheets are processed in presses and formed to half shells. Larger components can be produced by joining the half shells, which results in hollow bodies. However, current manufacturing technologies allow only cap profile shaped joints, which cause fiber deflections in the joint plane. This paper shows that overlapping infrared welds in organo sheets enable weld strengths close to the interlaminar shear strengths of the unwelded materials and thus a fiber utilization across the joint plane. By using high welding pressures, a matrix depletion and a change of the fiber alignment in the weld plane may occur which causes low weld strengths. Therefore, criteria for the successful welding were defined and various possibilities to optimize the weld strengths were investigated.

No description available.

Bats occupy diverse and unique niches and are regarded as important components in maintaining ecosystem health. They are major consumers of nocturnal insects, serve as pollinators, seed disperser, and provide important economic benefits as consumers of agricultural and forest pest insects. Bats have been proposed as good indicators of the integrity of natural communities because they integrate a number of resource attributes and may show population declines quickly if a resource attribute is missing. Establishing community- and population-level data, and understanding species interactions is especially important in changing landscapes and for species whose populations levels are threatened by outside factors of anthropomorphic disturbance from hibernacular visitation to energy production and fungal pathogens. For these reasons I have set out to establish habitat use patterns, detection probabilities, spatial and temporal occupancy, and investigate species interactions. This thesis is broken down into three distinct chapters each intended to be a stand-alone document. The first establishes the basic ecology from natural history accounts, provides an overview of the various sampling strategies, and gives a comprehensive description of the study area. The seconds sets out to identify the factors influencing detection probabilities and occupancy of six sympatric bats species and provide insight into habitat use patterns. The third examines spatial and temporal activity patterns and investigates species interactions. This study can provide understanding into the secretive and poorly understood patterns of free flying bats across the landscape. It can also deliver useful information to land managers regarding potential changes in landscape practices for the conservation of bat species. / Master of Science

This thesis examines the viability of the concept of political liberalism. Since its emergence, the idea of a purely political liberalism has been the subject of a voluminous amount of discourse and debate. The concept of political liberalism has been presented as both a solution to the problems of justice and political stability troubling liberal democracies and an exemplar of all that is wrong with contemporary political philosophy; it has, quite literally, altered the landscape and the vernacular of contemporary political theory. Herein it is argued that, despite the significant amount of literature that has been devoted to the analysis of the idea of a purely political liberalism, the idea itself has yet to be subjected to the type of critique that is required if one is to assess its viability effectively. Though there have been a number of contemporary political theorists who have developed conceptions of political liberalism which they believe differ in important ways from those of their doctrinal colleagues, detailed analyses of the concept of political liberalism have and remain focussed almost exclusively on a single formulation: namely, Rawlsian political liberalism. This singular focus has precluded the completion of a comprehensive assessment of the viability of the concept (as opposed to a single conception) of political liberalism as represented both by Rawlsian and non-Rawlsian models. This thesis confronts this problem by expanding the scope of investigation to include a fulsome examination of other prominent paradigmatic conceptions of political liberalism namely, those developed by Charles Larmore and Judith Shklar and in so doing provides a more inclusive and, subsequently, thorough critique than has previously been offered. Adopting such an approach reveals that, despite protestations to the contrary, the prominent paradigmatic conceptions of political liberalism are sufficiently similar in all important respects to enable their conflation for the purpose of analysis; and when subjected to a thorough analysis, the idea of a purely political liberalism proves itself to be untenable. / Political Science / D. Litt. et Phil. (Politics)