Sökresultat

Heat transfer losses are one of the largest loss contributions in a modern internal combustion engine. The aim of this study is to evaluate the contribution of the piston bowl type and swirl ratio to heat losses and performance. A commercial CFD tool is used to carry out simulations of four different piston bowl geometries, at three engine loads with two different swirl ratios at each load point.

The excavations of one of the plots in the Black Earth at Birka revealed an unusually large number of objects associated with long-distance eastern contacts. Among the objects was a Volga Bulgarian pot and a hoard containing Volga Bulgarian imitations of dirhams. The surprisingly high proportion of Volga Bulgarian coins in the hoard indicates that the person(s) who lived on the plot in the mid ten

The generalized Pareto distribution (GPD) is a two-parameter family of distributions which can be used to model exceedances over a threshold. We compare the empirical coverage of some standard bootstrap and likelihood-based confidence intervals for the parameters and upper p-quantiles of the GPD. Simulation results indicate that none of the bootstrap methods give satisfactory intervals for small s

This chapter is intended as a background on natural photosynthesis for those interested in artificial photosynthesis. It describes how light is used for creating positive and negative charges, and how these charges are transferred through the molecular assemblies in the membranes. Next, the chapter also describes how the charge transport leads to creation of a pH difference across the photosynthet

Bone and soft tissue tumors (BSTT) belong to a diverse group of solid tumors of mesenchymal origin, with a large number of histological types affecting individuals of all ages. The general aim of the present thesis (Articles I-V) was to investigate in detail the genetic aberrations in selected subtypes of benign and malignant BSTT. Aberrations identified by chromosome banding analysis were studied

The sensitivity of biosensors can be increased substantially by incorporation in a substrate recycling scheme. Based on the amplification of NAD+/NADH by the recycling reaction catalyzed by glycerol dehydrogenase (GDH) and diaphorase, NAD+/NADH can be determined amperometrically with around 1000 times higher sensitivity than for the substrate sensing mode. The sensitivity of enzyme electrodes were

The general aim of this thesis was to study how memorial places and objects serve as links and meeting points between the bereaved and their conceptions and memories of the departed. This has been examined in several different ways, from various viewpoints, and placed in different contexts and periods in time. The general result is that there are several and complementary ways through which materi

riskhantering, krishantering och lärande, tekniska infrasystems sårbarhet, risk- och sårbarhetsanalys, krishanteringssystem

The numbers of Somali immigrants in Sweden has increased during the last years and there is a need of more competence for teaching Swedish as a second language to this group.Star This paper investigates aspects of difficulties in the pronunciation of Swedish for Somali speakers. Recordings of two Somali speakers living in Sweden have been analyzed and it is obvious that there are pronunciation dif

Popular Abstract in Swedish Det stora flertalet bakterier som människan kommer i kontakt med är helt ofarliga och i vissa fall även nyttiga, eller till och med nödvändiga för oss. De bakterier som orsakar sjukdom utgör således en liten minoritet, men åsamkar trots det stort lidande och höga kostnader i alla världens länder. En av de vanligaste sjukdomsframkallande bakterierna heter Streptococcus pThe bacterial surface can be thought of as the interface where pathogenic bacteria encounter the human host. Interactions between bacterial surface proteins and human proteins are important determinants of the eventual outcome of infection. A bacterial protein, Protein F1, that binds the human plasma and connective tissue protein fibronectin, was found to reduce the virulence of Streptococcus pyog

Radionuclide imaging of cardiac function represents a number of well-validated techniques for accurate determination of right (RV) and left ventricular (LV) ejection fraction (EF) and LV volumes. These first European guidelines give recommendations for how and when to use first-pass and equilibrium radionuclide ventriculography, gated myocardial perfusion scintigraphy, gated PET, and studies with

“Energy Futures Øresund” is the final report on the energy system of the Øresund Region. It comprises a regional overview of the current state and trends of selected energy systems, discussions on potential technological solutions to overcome barriers and an analysis of the energy strategy of the island Bornholm. The report forms the basis for further strategic energy planning of Energi Öresund, a

The UWB circular disc monopole (CDM) antenna has been previously used for positioning applications. But at higher frequencies, its pattern does not remain omnidirectional in azimuth and it tends to shift upward. We propose new structures for both monopole radiator and ground plane to yield an antenna with a stabilized radiation pattern. Comparing the main lobe characteristics of the proposed and C