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Comparison between a novel claw-pole electrically magnetized synchronous machine without slip-rings and a permanent magnet machine

Electrical machines used in EV/HEV traction applications are usually driven at speeds where field weakening operation is required. In this region, electrically magnetized machines are more easily operated than permanent magnet machines. This paper discusses the performance of an electrically magnetized synchronous machine where the field coils are placed in magnetically conducting end-plates attac

On Tailbiting Codes from Convolutional Codes

Popular Abstract in Swedish Denna avhandling behandlar en speciell typ av felrättande koder som kallas tailbitingkoder. Syftet med en felrättande kod är att korrigera fel som kan uppkomma på grund av brus och störningar då digital information överförs från sändare till mottagare.Tailbiting is a method to terminate convolutional codes into block codes. We call these block codes tailbiting codes. This thesis focuses on the encoding of tailbiting codes. The tailbiting method is carefully investigated. Conditions for when the tailbiting method fails are given, and methods for the proper initialization of the encoder are presented. Furthermore, the minimum distances of the tai

DC-DC Converters - Dynamic Model Design and Experimental Verification

To obtain high performance control of a dc-dc converter, a good model of the converter is needed. The load usually affects the dynamics and one way to take this into consideration is to regard the load as a part of the converter. The load is often the most variable part of this system. If the load current and the output voltage are measured there are good possibilities to obtain a good model of th

Transport, bebyggelse och utvecklingskontroll : En komparativ stadsgeografisk studie

Syftet med avhandlingen är att klarlägga de intraurbana sambanden mellan transportstruktur, bebyggelsestruktur och maktstruktur (utvecklingskontroll). Viktiga faktorer för samspelet som vi urskiljt är verksamhets- och bostadslokalisering, densitet, centrumstruktur, transportsystemets uppbyggnad och färdmedelsval. Faktorerna sammanfattas i en enkel modell. Sambanden har undersökts i fem utländska f

Some exact union bound results for maximum likelihood detection in MIMO systems

In this paper we investigate some properties of the union bound for a basic MIMO system, assuming uncoded QAM transmission, uncorrelated Rayleigh fading, and maximum likelihood detection. The presented union bound results cover several choices of the number of transmitting and receiving antennas (up to 16). It is also illustrated how the pair-wise error probability approaches the Q( )-function as

LES of the flow and acoustics generated by a wing installed aircraft propeller running in the vicinity of the ground

A study on the noise generated by a subsonic four bladed propeller installed on a wing of an aircraft near the ground is presented. The method used is based on an acoustical analogy developed by Ffowcs Williams and Hawkings. Computations of the flow field are performed using LES with the incompressible fluid assumption, while the noise is evaluated using a non-homogeneous wave equation. The aim is

Photochemistry of Eumelanin Precursors Role of Excited State Proton Transfer for UV Photoprotection

Popular Abstract in Swedish Melanin är ett pigment som finns i många olika slags vävnader. I hud och hår finns två slags melanin, pheomelanin som är typiskt för rödhåriga personer och eumelanin som finns i större mängd i mörkt hår och hud. Konstaterad korrelation mellan hudcancer och solexponering motiverar forskarna att förstå mer om melanin och dess växelverkan med UV-ljus. Man vet att rödhårigaMelanin is an epidermal pigment commonly known to give darker skin coloration under sun exposure. It is also present in the hair, eyes, inner ear and brain. The first function of epidermis melanin is believed to be photoprotective against harmful ultraviolet (UV) light, but the recent increase of skin cancer correlated to an increase of sun exposure questions the properties of melanin. Its presenc

Parapsychology: A handbook for the 21st century

This book is the first in almost 40 years to provide a comprehensive scientific overview of research in the field of parapsychology, explaining what we know and don’t know about so-called psi phenomena, such as “telepathy,” “precognition” or “psychokinesis.” Contributors evaluate the evidence for these phenomena, accounting for factors such as selective memory, wish fulfillment and incorrect metho