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Renewable energy systems are likely to become wide spread in the future due to environmental demands. As a consequence of the dispersed nature of renewable energy systems, this implies that there will be a distributed generation of electric power. Since most of the distributed electrical energy sources do not provide their electric power at line frequency and voltage, a DC bus is a useful common c

The paper is in part an evaluation of using virtual focus groups in existing commercial platforms as a research method, in part a pilot study on motives and perceptions of Facebook users concerning political participation in social media. Two focus groups were set up in the commercial social network Facebook, consisting each of six participants, all of them residing in Sweden. One of the groups co

The use of a hydrogen-sensitive palladium-metal oxide semiconductor (Pd-MOS) sensor in combination with a membrane for liquid-to-gas transfer for the detection of dissolved hydrogen was investigated. The system was evaluated with known concentrations of dissolved hydrogen in water. The lowest concentration detected with this set-up was 160 nM. The method was applied to monitoring of a laboratory-s

This paper describes the design, simulation and measurement of a GaN power amplifier suitable for envelope and phase signal combination. The low-frequency envelope signal is used to vary the gate (bias) voltage of the device, resulting in a pulse width modulated drain voltage, while modulation of supply voltage or current is avoided. The test circuit is implemented using a discrete GaN HEMT power

Two alternative Human-Machine-Interface solutions for in-vehicle speed support were evaluated in field trials in Hungary and Spain. Twenty vehicles on both test sites were equipped with two kinds of systems: 1) support via an Active Accelerator Pedal and 2) warning via beep signals and flashing red light when exceeding the speed limit. The test drivers drove one month with each system. Both system

This paper presents a novel memory optimization technique to exploit the analogy between correlation coefficients in MMSE-based channel estimators across multiple standards. The need for coefficient storage for robust MMSE channel estimators is expensive in terms of on-chip memory. Besides, the memory requirements grow linearly by integrating more standards onto one platform. Thus, it becomes inev

Strategy and methodology is presented for the analysis of organic pollutants, with the purpose of evaluating treatment procedures for landfill leachate. Today, many investigations of treatment procedures are focusing on the measurement of water quality parameters such as chemical and biochemical oxygen demand, (COD and BOD), and total organic carbon, (TOC) when assessing the organic compounds in w

Performance demands put on combustion engines are ever increasing, e.g. demands on emissions and fuel consumption. The increased demands together with new combustion concepts increase the need for feedback engine and combustion control. Mathematical models are considered important in order to implement high performance feedback control, as well as to perform diagnostic functions in vehicles. Vario

The purpose of this study was to examine voluntary organizations’ lobbying around hiv and aids in Sweden and to compare how organizational conditions influence this work. To do so I have analyzed two different Swedish organizations, RFSU and Noaks Ark Stockholm. They are both working with lobbying around hiv and aids but have at the same time different organizational conditions for this work. More

The Fire Risk Index Method is a tool for assessing fire safety in multi-storey apartment buildings. This report contains a description of how Version 1.2 of the Fire Risk Index Method was developed. The terminology frequently used in the development process of the method is also explained. The use of the Fire Risk Index Method is described and illustrated by an example. The method is applied to an