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Weak alignment of requirements engineering (RE) with verification and validation (VV) may lead to problems in delivering the required products in time with the right quality. For example, weak communication of requirements changes to testers may result in lack of verification of new requirements and incorrect verification of old invalid requirements, leading to software quality problems, wasted ef

The thesis focuses on the numerical simulation of the flow field in gas turbine burners. Due to tougher and tougher requirements on low levels of emission of pollutants there is a need for new combustion technologies. In gas turbines one method to attain low pollutant levels is the use of lean premixed combustion. However, in lean combustion, problems related to the flame stability can arise. Swi

The aim of this study was to demonstrate electronic speckle pattern interferometry (ESPI) as a powerful tool in determining diffusion coefficients and partition coefficients for proteins in gels. ESPI employs a CCD camera instead of a holographic plate as in conventional holographic interferometry. This gives the advantage of being able to choose the reference state freely. If a hologram at the,re

The Major Intrinsic Proteins, MIPs, constitute a large, ancient superfamily of membrane proteins that are found in all kingdoms of life. Most MIPs facilitate passive diffusion of water across biological membranes (aquaporins), although many channels are also permeable for glycerol and other small uncharged solutes, (aquaglyceroporins). Other substrates reported for specific MIPs are anions, carbon

Landscape genetics offers a powerful approach to understanding species’ dispersal patterns. However, a central obstacle is to account for ecological processes operating at multiple spatial scales, while keeping research outcomes applicable to conservation management. We address this challenge by applying a novel multilevel regression approach to model landscape drivers of genetic structure at both

Over the past few decades, numerous wide (> 103 au) binaries in the Galactic field and halo have been discovered. Their existence cannot be explained by the process of star formation or by dynamical interactions in the field, and their origin has long been a mystery. We explain the origin of these wide binaries by formation during the dissolution phase of young star clusters: an initially unbound

Aim: The Driving to Learn project focused on people with profound cognitive disabilities and their possible achievements from practicing joystick-use in a powered wheelchair. The aim of this study within the project was to statistically analyse the participants' outcomes, and to explore factors, in terms of participant and training characteristics, associated with a favourable outcome of training

As the identification process is based on the unique patterns of the users, biometrics technologies are expected to provide highly secure authentication systems. The existing systems using fingerprints or retina patterns are, however, very vulnerable. One’s fingerprints are accessible as soon as the person touches a surface, while a high resolution camera easily captures the retina pattern. Thus,

Background Carrying the cyclin-dependent kinase inhibitor 2A (CDKN2A) germline mutations is associated with a high risk for melanoma. Penetrance of CDKN2A mutations is modified by pigmentation characteristics, nevus phenotypes, and some variants of the melanocortin-1 receptor gene (MC1R), which is known to have a role in the pigmentation process. However, investigation of the associations of both

Popular Abstract in Swedish Avhandlingen utreder några av konsekvenserna av de institutionella reformer som genomfördes i Sydafrika under 1990-talet, med särskilt fokus på det nya kommunsystemet, enligt vilket varje kommun är skyldig att stimulera lokal ekonomisk utveckling i samarbete med det lokal näringslivet och andra civilsamhälleliga aktörer. Den syftar även till att utveckla den samhällsvetThis thesis focuses on the consequences of the institutional transformations in South Africa during the 1990s with specific reference to the introduction of a mode of local governance based on the direct participation of private and civic actors in policymaking and implementation. The study also aims to contribute to theory. The approach is that public, private and civic associations are best unde

Energy balances are analysed from a life-cycle perspective for biogas systems based on 8 different raw materials. The analysis is based on published data and relates to Swedish conditions. The results show that the energy input into biogas systems (i.e. large-scale biogas plants) overall corresponds to 20-40% (on average approximately 30%) of the energy content in the biogas produced. The net ener

As the identification process is based on the unique patterns of the users, biometrics technologies are expected to provide highly secure authentication systems. The existing systems using fingerprints or retina patterns are, however, very vulnerable. One's fingerprints are accessible as soon as the person touches a surface, while a high resolution camera easily captures the retina pattern. Thus,

Shedding of epithelium, increased venular permeability, and traffic of activated eosinophils and neutrophils may characterize asthmatic airways. This in vivo study involving briefly anesthetized guinea pigs examines whether epithelial denudation itself affects airway venules and granulocytes. Using an oral probe, a de-epithelialized tracheal zone (0.8 x 30 mm) was produced without bleeding or dama

Today's handheld computing devices equipped with novel wireless network technologies can provide their users with features such as mobility, multimedia support and group communication. On the other hand, the administrative effort required to enable all these features increases beyond the level that an ordinary user can manage. Ad hoc networks, being able to quickly organise themselves without user

Variations in molybdenum isotopic composition, spanning the range of similar to 2.3 parts per thousand in the terms of Mo-97/Mo-95 ratio, have been measured in sediment cores from three lakes in northern Sweden and north-western Russia. These variations have been produced by both isotopically variable input of Mo into the lakes due to Mo isotopic heterogeneity of bedrock in the drainage basins and

Wheat straw is an abundant agricultural residue which can be used as a raw material for bioethanol production. Due to the high xylan content in wheat straw, fermentation of both xylose and glucose is crucial to meet desired overall yields of ethanol. In the present work a recombinant xylose fermenting strain of Saccharomyces cerevisiae, TMB3400, cultivated aerobically on wheat straw hydrolysate, w

Power supply systems play a very important role in applications of everyday life. Mainly, for low power generation, there are two ways of producing energy: electrochemical batteries and small engines. In the last few years many improvements have been carried out in order to obtain lighter batteries with longer duration but unfortunately the energy density of 1 MJ/kg seems to be an asymptotic value

Popular Abstract in Swedish Avhandlingen består av fyra kapitel som behandlar olika aspekter av internationell handel och dess effekter på konkurrens och produktivitet. Särskilt behandlas effekterna av EU:s expansion och fördjupade integration. Första kapitlet använder den så kallade gravitationsmodellen för att analysera hur integrationsprocessen av de Central- och Östeuropeiska länderna i EU haThis thesis consists of four papers on trade, competition and productivity with particular emphasis on the effects of various aspects of the deepening and widening of the European Union. The first paper Trade Creation, Diversion and Displacement of the EU Enlargement Process provides an assessment of the effects of the EU enlargement process on trade. A new method of estimating the gravity model

The effect of the anionic surfactant SDS (sodium dodecyl sulfate) on the adsorption behaviors of cationic hydroxyethyl celluloses (Polymer JR-125, JR-400, and JR-30M) and hydrophobically modified cationic cellulose (Quatrisoft LM-200) at silica surfaces in the presence of a 10 mM NaCl solution has been investigated by null ellipsometry. The adsorbed amount of LM-200 is found to be considerably lar