Current-mode control can be used to control switched DC-DC power converters. This paper compares two continuous-time models for current-mode control that are made to be accurate up to half the switching frequency. The two models are the ones presented by Ridley and Tan. The closed loop frequency responses predicted by these two models are compared with results obtained from simulations of a buck c

Riter och ritual är mångsidiga fenomen vilket gör att studiet av formaliserade handlingar återfinns inom flera ämnesdiscipliner. I Den rituella människan – flervetenskapliga perspektiv visar forskare inom arkeologi, etnologi, psykologi, teatervetenskap, religionshistoria och teologi hur de har funderat över den rituella praktiken. Varför använder människan sig av riter, hur kan rit och ritual stud

Web sites are exposed to high rates of incoming requests. The servers may become overloaded during temporary traffic peaks when more requests arrive than the server is designed for. An admission control mechanism rejects some requests whenever the arriving traffic is too high and thereby maintains an acceptable load in the system. This paper presents how admission control mechanisms can be designe

Governmental organisations are becoming more critically dependant on IT systems such as communication systems or patient data systems, both for their everyday tasks and their role in crisis relief activities. Therefore it is important for the organisation to analyse the reliability of these systems as part of the organisation’s risk and vulnerability analysis process. This paper presents a practic

Lattice Boltzmann method (LBM) is a method that can be used to capture the detailed activities of the transport processes at microscale. Here LBM is used to model the porous anode for an anode-supported Solid Oxide Fuel Cell (SOFC). The purpose of this study is to investigate the effects of electrochemical reactions on the transport processes by a 3D model at microscale. A porous 3D modeling domai

Popular Abstract in Swedish Denna avhandling beskriver tillverkning av partiklar av metaller och halvledare samt dessas användning i nya typer av elektroniska komponenter och nanostrukturer. Partiklarna tillverkas med aerosolteknik, dels med kända metoder och dels med nyutvecklade. Partiklarna är mellan 5 och 80 nanometer (miljarddels meter) i diameter, och deras bildning, struktur och sammansättnAerosol technology was used to develop new methods for fabrication of size-selected, nanometer-sized particles of metals and semiconductors. Such particles were used to realize different types of quantum devices and nanometer-sized structures. The thesis contains an introduction, five papers on particle fabrication, and five papers on particle-based quantum devices. Size-selected gallium and indi

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Popular Abstract in Swedish Blodkärlen har till uppgift att distribuera syre och näring till kroppens alla celler, samt att borttransportera slaggprodukter som sedan bildas efter nyttjandet. Dessutom förmedlas en rad signalsubstanser till kroppens vävnader via blodcirkulationen. Eftersom mängden cirkulerande blod är begränsad är det viktigt att blodkärlen, bestående av artärer som för blodet från This thesis aims at characterizing the endothelin (ET) receptors in different vascular beds of man and rat. The ET-A receptor was shown to be the only contractile ET receptor present in all vascular regions, with the exception of the rat mesenteric vein where a weak ET-B receptor-mediated contraction was seen. Treatment with antisense oligodeoxynucleotides to the ET-A receptor mRNA during organ cu

The objectives of this project were to estimate network-based crash prediction models that will predict the expected crash experience in any given geographic area as a function of the highway link, intersection and land use features observed in the area. The result is a system of GIS programs that permit a polygon to be drawn on a map, or a set of links and intersections to be selected, and then p

Faster than Nyquist (FTN) signaling is extended. We send FTN pulse trains that overlap in both time and frequency; this is called two dimensional Mazo signaling. The minimum time and frequency separation that achieves square minimum distance 2 for root raised cosine pulses is found. Two dimensional signaling is more bandwidth efficient than one dimensional. A simple decoder is tested and it verifi