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Laser-driven particle acceleration - Experimental investigations

This thesis describes experimental studies of laser-driven particle acceleration. With the focused intensity of today’s high-power lasers exceeding 10^18 W/cm2,extremely high-gradient accelerators are possible. A number of experiments have been performed using two different laser systems, the Lund multi-TW laser and the Vulcan laser at CLF/RAL, UK, to study aspects ranging from laser system optimi

MIMO systems with antenna selection - an overview

We consider multiple-input - multiple-output (MIMO) systems with reduced complexity. Either one, or both, link ends chose the "best" L out of N available antennas. This implies that only L instead of N transceiver chains have to be built, and also the signal processing can be simplified. We show that in ideal channels, full diversity can be achieved, and also the number of independent data streams

Flexible Learning in a Digital World

Abstract Concepts as flexible learning, lifelong learning, life wide learning, individualization, globalization are discussed. What does it mean and what are the consequences on HEI perspectives. The critical issue is who are the learners and the learning providers and what are their frames of references.

Transmission Electron Microscopy of Semiconductor Nanowires

Semiconductor nanowires are studied by using transmission electron microscopy (TEM) based methods in this work. In the first section, the growth mechanism of gallium arsenide nanowires grown by chemical beam epitaxy is investigated. The nanowires are epitaxially grown from a gallium arsenide substrate by using gold seed particles as catalysts. The growth of gold particle catalysed nanowires is oft

Structure and Motion from Points, Lines and Conics with Affine Cameras

We present an integrated approach that solves the structure and motion problem for affine cameras. Given images of corresponding points, lines and conics in any number of views, a reconstruction of the scene structure and the camera motion is calculated, up to an affine transformation. Starting with three views, two novel concepts are introduced. The first one is a quasi-tensor consisting of 20 co

Döden som katharsis. Nordiska perspektiv på dödens kultur och mentalitetshistoria

Döden är ett evigt tema. Men diskursen runt döden i dess mångskiftande former är underkastad ständig förändring. Döden kan ses som ett hot och ett gissel men också som en befrielse, ett straff eller som ett redskap för att befria samhället från oönskade individer. I samtliga fall kan man tala om döden som en reningsprocess – som katharsis. Det är denna föränderliga diskurs som kommer att behandlas

Environmental Monitoring by Multi-Spectral Lidar Techniques

Popular Abstract in Swedish I vår omgivning finns många gasformiga ämnen, vars egenskaper är sådana att de kan mätas med optiska metoder. Härvid kan man utnyttja det unika spektroskopiska fingeravtryck ämnena har. Det vill säga, att varje ämne absorberar ljus av olika färg (våglängd) på ett unikt sätt. Likaså har vissa ämnen sådana egenskaper, att då de belyses med en viss våglängd sänder de ut enMulti-spectral lidar (light detection and ranging) techniques have been developed and employed in various environmental studies, ranging from concentration mapping of volcanic emissions to fluorescence imaging of historical monuments. In both absorption measurements of gaseous species and fluorescence imaging of stones, multiple wavelength excitation and multiple wavelength detection have been app