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For some time, directional antennas have been considered to solve connectivity and interference issues in wireless networks. Several scenarios have been presented and often the conclusions drawn are positive, showing increase in capacity. However, to date there has been no effort to assess a holistic picture of the benefit/cost tradeoff and previous work mainly concerns either link scheduling or a

Tristan da Cunha is a volcanic island group situated in the central South Atlantic. The oldest of these islands, Nightingale Island, has an age of about 18Ma. In the interior of the island, there are several wetlands situated in topographic depressions. The ages of these basins have been unknown, and their genesis has been debated. Aiming towards the reconstruction of the geomorphological history

Multiple-input multiple-output (MIMO) is a mandatory feature of the Third Generation Partnership Project (3GPP) Long Term Evolution. This work investigates the performance of a low complexity channel estimator for LTE terminals with an emphasis on the 4 × 4 multiple antenna scheme. The presented work extends a promising low-complexity 2 × 2 MIMO channel estimator to the 4 × 4 MIMO case and evaluat

We present the PalCom Object Notation, a textual data representation format for communication between internet of things which support binary and textual data. The format does not require parsing of user data (or the “payload”) and is thus efficient to use also for large binary values such as digital images, audio and video as well as for short textual values. These can be mixed in the same messag

The nature of scientific research and the development of scientific software have similarities with processes that follow the agile manifesto: responsiveness to change and collaboration are of the utmost importance. But how well do current scientific software development processes match the practices found in agile development methods, and what are the effects of using agile practices in such proc

A common method for comparing the result of different global circulation models (GCMs) under different emission scenarios is to study global climate response variables, such as mean temperature. An interesting alternative measure of climate sensitivity is to study the biosphere’s response to the different climate scenarios. The Lund-Postdam-Jena (LPJ) global vegetation model and its extension LPJ-

BEAN is a recent stream cipher proposal that uses Feedback with Carry Shift Registers (FCSRs) and an output function. There is a sound motivation behind the use of FCSRs in BEAN as they provide several cryptographically interesting properties. In this paper, we show that the output function is not optimal. We give an efficient distinguisher and a key recovery attack that is slightly better than brut

This thesis is based on five papers (A-E) treating estimation methods for unbounded densities, random fields generated by Lévy processes, behavior of Lévy processes at level crossings, and a Markov random field mixtures of multivariate Gaussian fields. In Paper A we propose an estimator of the location parameter for a density that is unbounded at the mode. The estimator maximizes a modified lik

In this paper, we study a flexible routing strategy for demand protection and a corresponding optimization problem for networks that permanently experience fluctuations of the capacity available on their links. This is an important and novel topic as limited link availability is a fundamental feature of wireless networks; yet majority of work in survivable network design is restricted to total fai

Although the research on the design of heterogeneous concurrent systems has a long and rich history, a unified design methodology and tool support have not emerged so far. Therefore, the creation of such systems remains a difficult, time-consuming and error-prone process. The absence of principled support for system evaluation and optimization at high level of abstraction makes the quality of the

Quality requirements complement functional requirements with information on the target quality levels of software functions or emergent system quality aspects. In release planning the allocation of development effort in further investments into product enhancements, new or enhanced functions are competing with quality improvements for limited resources. When setting balanced quality targets for de

Using Monte Carlo methods, we explore and compare the effects of two protein crowders, BPTI and GB1, on the folding thermodynamics of two peptides, the compact helical trp-cage and the β-hairpin-forming GB1m3. The thermally highly stable crowder proteins are modeled using a fixed backbone and rotatable side-chains, whereas the peptides are free to fold and unfold. In the simulations, the crowder p

PalCom is a pervasive middleware that enables users to combine the services on devices into useful configurations. Interconnected PalCom devices can discover, and keep track of, the existence of each other by exchanging periodic heartbeats within local networks, and once-sent device appearance/disappearance notifications across interconnected networks. This approach has the advantage of eliminatin

Today’s multimedia and DSP applications impose requirements on performance and power consumption that only custom processor architectures with SIMD capabilities can satisfy. However, the specific features of such architectures, including vector operations and high-bandwidth complex memory organization, make them notoriously complicated and time consuming to program. In this paper we present an aut

This paper describes the extraction of information on lethal events from the Swedish version of Wikipedia. The information searched includes the persons’ cause of death, origin, and profession. We carried out the extraction using a processing pipeline of available tools for Swedish including a part-of-speech tagger, a dependency parser, and manually-written extraction rules. We also extracted stru

In this paper, we propose a soft-output detector for multiple-input multiple-output (MIMO) channels that utilizes achievable information rate (AIR) based partial marginalization (PM). The proposed AIR based PM (AIR-PM) detector has superior performance compared to previously proposed PM designs and other soft-output detectors such as K-best, while at the same time yielding lower computational comp

In the atmosphere nighttime removal of volatile organic compounds is initiated to a large extent by reaction with the nitrate radical (NO3) forming organic nitrates which partition between gas and particulate phase. Here we show based on particle phase measurements performed at a suburban site in the Netherlands that organic nitrates contribute substantially to particulate nitrate and organic mass