Resonant tunneling through a single layer of self-assembled quantum dots (QDs) as well as tunneling through two layers of vertically aligned (stacked) dots is investigated. The difference between single and double layers of QDs can be viewed as going from a two-dimensional emitter to a zero-dimensional emitter. By fabricating small-area devices we are able to probe single stacks of quantum dots, r

Erkännande och dess motsats, missaktning, präglar i princip all mänsklig samvaro och interaktion. I boken presenteras och diskuteras ett antal socialfilosofiska och sociologiska perspektiv på temat erkännande, till exempel: Vad innebär det att erkänna en annan människa? Vilka olika former av erkännande och missaktning finns det?

The thesis contains three papers that comprise studies of the dynamic behaviour of involute spur and helical gears, and one paper that describes a method to determine the influence of misalignment on the static helical gear tooth stress. In the first study, the influence of the contact ratio on the dynamic response of a spur gear was examined. The spur gear pair was modelled using a single degree

Popular Abstract in Swedish I denna avhandling studeras egenskaper hos tvådimensionella, kvantmekaniska mångpartikelsystem. Studierna utförs med spinndensitetsfunktionalteori (SDFT) med den lokala spinndensitetsapproximationen (LSDA), samt med numerisk exakt diagonalisering. De egenskaper som studeras inkluderar symmetribrytande tillstånd i kvantprickar med få elektroner, gap i inneslutna fåpartikThis dissertation investigates properties of two-dimensional many-body systems. Studies are performed using the Spin-Density Functional Theory with the Local Spin-Density Approximation, and numerical exact diagonalization. The properties studied include symmetry-breaking states in few-electron quantum dots, gaps in confined few-body systems, magnetic properties of cold fermionic atoms in optical l

Astrobiologi kallar vi det vetenskapliga sökandet efter liv i rymden som görs av den jordbundna varelsen Homo sapiens sapiens och som utförs på en vanlig planet kring en vanlig sol bland miljarder andra stjärnor och galaxer. Under hennes i universellt perspektiv korta historia på jorden har hon ofta, när hon blickat upp på den stjärnbeströdda natthimlen, undrat över de grundläggande existentiella

In the studies presented in this thesis, hyperpolarized tracers have been used for the study of macroscopic flow and capillary perfusion with magnetic resonance imaging. The feasibility of performing vascular studies using echo-planar imaging (EPI) and hyperpolarized 129Xe was investigated using xenon dissolved in ethanol prior to injection into a flow phantom. It was concluded that hyperpolarized

Popular Abstract in Swedish Den globala landbaserade kolcykeln reglerar mängden växthusgaser i atmosfären. För närvarande tas varje år 25-30% av våra utsläpp upp av de landbaserade ekosystemen vilket är en viktig ekosystemtjänst som kanske inte kommer att bestå i längden. Upptagskapaciteten av både hav och landbaserade ekosystem tenderar att försvagas av global uppvärmning. Detta leder till att enThe global terrestrial carbon cycle plays a pivotal role in regulating the atmospheric composition of greenhouse gases. Currently it is responsible for removing 25-30% of our emissions every year, an important ecosystem service that may not persist in the long term. Global warming tends to decrease the CO2 sink capacity of the world’s oceans and ecosystems leading to a larger fraction of our emiss

[abstract missing]

In this paper, we develop a computational method for model reduction of polynomial dynamical systems. This is achieved using sum of squares relaxations on certain Lyapunov inequalities, which are the nonlinear counterparts of the Lyapunov controllability and observability linear matrix inequalities for linear systems. In our model reduction procedure, we use notions of balanced realization and bal

The proper handling of alarms is crucial to automated process control. In practice, many alarms are only distractive and do not represent a fault situation. Here a toolbox, that uses an expert system called LARA, is proposed that aims to reduce the occurrence of so-called nuisance alarms. It is based on a signal classification scheme to propose suitable alarm handling algorithms according to the s