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Frequency Estimation Based on Hankel Matrices and the Alternating Direction Method of Multipliers

We develop a parametric high-resolution method for the estimation of the frequency nodes of linear combinations of complex exponentials with exponential damping. We use Kronecker's theorem to formulate the associated nonlinear least squares problem as an optimization problem in the space of vectors generating Hankel matrices of fixed rank. Approximate solutions to this problem are obtained by usin

Direction of Arrival Estimation with Arbitrary Virtual Antenna Arrays using Low Cost Inertial Measurement Units

In this paper, we have investigated the use of virtual antenna arrays at the receiver to do single antenna direction-of-arrival estimation. The array coordinates are obtained by doing simple dead reckoning using acceleration and angular speed measurements from a low cost micro-electro-mechanical system inertial measurement unit (IMU). The proposed solution requires no extra hardware in terms of re

An Encounter with Convolutional Codes over Rings

Convolutional codes is one possibility when there is a need for error-correcting codes in communication systems. Using convolutional codes over rings is a relatively new approach. When coding is used in combination with, for example, phase-shift keying, codes over rings constitue a natural choice as the symbols in the code alphabet have a natural signal point interpretation. This thesis reports on

Can preschoolers profit from a teachable agent based play-and-learn game in mathematics?

A large number of studies carried out on pupils aged 8–14 have shown that teachable agent (TA) based games are beneficial for learning. The present pioneering study aimed to initiate research looking at whether TA based games can be used as far down as preschool age. Around the age of four, theory of mind (ToM) is under development and it is not unlikely that a fully developed ToM is necessary to

Att spåra tecken på lärande : Mediereception som pedagogisk form och multimodalt meningsskapande över tid

Popular Abstract in Swedish Denna studie handlar om mediereception som pedagogisk form och meningsskapande över tid. Jag är intresserad av att förstå komplexitet i meningsskapande processer som utgår från medieproduktioner. Syftet med avhandlingen är att undersöka vad mötet mellan en grupp lärarstudenter och deras texter kan erbjuda för möjligheter och begränsningar för meningsskapande över tid i The present study is about media reception as an educational form, supporting meaning-making over time. The thesis stems from the desire to understand the complexity in a meaning-making process that takes its point of departure in media productions. The aim is to investigate the possibilities and limitations for meaning-making over time, afforded by the meeting of a group of student teachers and t

Saturation spectroscopy for optically thick atomic samples

Doppler-free saturation spectroscopy in the regime of strong pumping intensities and optically thick atomic samples is investigated experimentally and theoretically. It is shown that a very high signal-to-background ratio can be obtained and, at the same time, subnatural linewidths can be reached. Further contrast and linewidth improvements can be attained by supplementing the primary depleted pum

Ungdomars väg från skola till arbetsliv - nordiska erfarenheter

This report highlights the conditions for young people trying to establish themselves in the labour market in the Nordic countries. The aim has been to examine similarities and differences with regard to specific aspects of the welfare systems with a focus on upper secondary school level and political initiatives in the labour market. The passage of students through upper secondary school, transit

Siri Dahlquist som lyriker

Siri Dahlquist (1889-1966) one of the first women achieving a theol.cand. degree in Sweden. Belonging to the Young Church Movement,as a poet, she reflects the themes of this movement: the calling,the imitation of Christ,the national church, and the mission. She shared the preference for domestic motifs, a simple style, and unobtrusiveness, with contemporary idyllist poets.

An improved interpolated array approach to DOA estimation in correlated signal environments

Abstract: Many popular direction-of-arrival (DOA) estimators rely on the fact that the array response vector of the array is Vandermonde, for example, that of a uniform linear array (ULA). Array interpolation is a preprocessing technique to transform the array response vector of a planar array of arbitrary geometry to that of a ULA over an angular sector. While good approximation within the target

Manipulation of Nanoparticles for Quantum and Single-Electron Devices

Popular Abstract in Swedish I ett atomkraftsmikroskop avbildar man ytor och föremål genom att känna av ojämnheter med hjälp av en vass spets. Spetsen har en diameter på ca en tusendel av ett hårstrå. I avhandlingen beskrivs en teknik för hur man med denna extremt vassa spets kan manipulera nanometerstora metall- och halvledar partiklar mellan elektroder på en yta för att bygga elektriska komponentIn this thesis a technique to manipulate nanoparticles with an atomic force microscope (AFM) is presented. Particles in the size range of 5-500 nm could be positioned in arbitrary two-dimensional patterns on different surfaces by mechanically pushing them with the AFM tip. The technique which is material-independent can be applied to any type of nanometer-sized particles or objects that are free t

Optimal side lobes under linear and faster-than-Nyquist modulation

We minimize the frequency and time occupancy of multicarrier binary linear modulation based on two-dimensional faster than Nyquist (FTN) signaling. FTN analysis provides the asymptotic time-frequency consumption per bit and prolate spheroidal wave analysis minimizes the side lobe occupancy. For both problems, an excellent choice is a Gaussian pulse, with some adjustment of the side lobes.

Employing Foreign Workers In Sweden Construction Sector

The enlargement of the European Union provides opportunities for members to be mobile in seeking various forms of permanent and non-permanent employment, particularly temporary work and contract labour. These changing conditions require quick reactions, overcoming soft issues such as language barriers and coping with culture clashes and political issues that could create problems for the worker. W

Collector test method under quasi dynamic conditions according to the European Standard EN 12975-2

In April 2001 the new European Standard EN 12975:2000: ''Thermal solar systems and components--Solar Collectors'' was established. With the publication of this European standard all national standards, related to the same topic, have to be withdrawn by the nations of the European Community. Now only one standard for testing solar collectors is valid throughout Europe.This European Standard specifi