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New laser-based techniques for nanometre lithography and microscopy

This thesis describes the development of new laser-based techniques for nanometre lithography and microscopy. The potential of a non-intrusive scanned near-field optical microscope (SNOM) has been investigated. The probe consists of an optically trapped microscopic particle which is scanned in proximity to the object to be studied. Compared with conventional SNOM's, this probe would allow high-res

Antenna currents for optimal Q, superdirectivity, and radiation patterns using convex optimization

The high Q-factor (low bandwidth) and low efficiency make the design of small antennas challenging. Here, convex optimization is used to determine current distributions that give upper bounds on the antenna performance. Optimization formulations for maximal gain Q-factor quotient, minimal Q-factor for superdirectivity, and minimum Q for given far-field are presented. The effects of antennas embedd

Onset of mould growth – the effect of climate variability and different geographic locations

This paper presents a study on how climate conditions at numerous locations in Sweden affect the risk of onset of mould on wood sheltered outdoors. The results indicate that the risk is clearly higher in the south compared to the north of Sweden. These differences are mainly explained by colder and dryer winter periods in the north which is unfavorable for development of mould. The results also sh

A sign-bit auto-correlation architecture for fractional frequency offset estimation in OFDM

This paper presents an architecture of an auto-correlator for Orthogonal Frequency Division Multiplexing systems. The received signal is quantized to only the sign-bit, which dramatically simplifies the frequency offset estimation. Hardware cost is reduced under the assumption that synchronization during acquisition does not have to be very accurate, but sufficient for coarse estimation. The archi

Technology, Institutions and Allocation of Time in Swedish Households 1920-1990

The modernisation of Swedish households during the twentieth century prompted a considerable productivity growth in household production, which reduced the time input for a fixed volume of routine household work by about 35 per cent 1920-1990. Much of that time was gradually transferred to the labour market, but no evidence can be found for an increase in leisure time. What has been termed a “Cowa