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Populärvetenskaplig sammanfattning:Dagens datorer har krympt i storlek i takt med den ständigt ökande kompetensen att tillverka transistorer med en anmärkningsvärd noggrannhet. Storleksskalan av nya transistorer börjar motsvara den av en handfull atomer.På denna skala dominerar kvantfysik, vilket är ett väsentligt hinder för de traditionella datorkomponenterna. Men detta innebär inte bara en begräThe work contained in this thesis deals with two closely related topics. Papers I-III deal with charge transport statistics in nanoscale devices to investigate the presence of entanglement in the constituent electrons. We identify the contributions of entangled electron pairs to the current cross-correlations as a signature of entanglement. Paper IV treats the electric control of a quantum dot bas

We investigate the effects of the orientation of the magnetic field and the orientation of a quantum dot, with respect to crystallographic coordinates, on the quality of an electrically controlled qubit realized in a gated semiconductor quantum dot. We find that, due to the anisotropy of the spin-orbit interactions, by varying the two orientations it is possible to tune the qubit in the sense of o

Barns internetanvändning äger i stor utsträckning rum i en kommersiell miljö där reklam och försäljning av virtuella föremål är ständigt närvarande. Genom att kombinera publikforskning, produktionsforskning samt textanalys (observationer online och dokumentanalys) bidrar denna avhandling till en kritisk förståelse av internet som en plats för barns vardagliga aktiviteter och deltagande, och som enChildren’s daily internet usage takes place to a large extent in a commercial environment, where advertising and the sale of virtual goods are ever-present parts of the online experience. The overall goal of this thesis is to contribute to a critical understanding of children’s commercial online environment as spaces for children’s everyday life activities and participation, and as spaces for comm

Cloud retrievals from the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments aboard the satellites Terra and Aqua and the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard the Suomi-NPP satellite are evaluated using a combination of ground-based instruments providing vertical profiles of clouds. The ground-based measurements are obtained from the Atmospheric Radiat

We have investigated the charge transfer mechanism in single crystals of DTBDT-TCNQ and DTBDT-F4TCNQ (where DTBDT is dithieno[2,3-d;2′,3′-d′] benzo[1,2-b;4,5-b′]dithiophene) using a combination of near-edge X-ray absorption spectroscopy (NEXAFS) and density functional theory calculations (DFT) including final state effects beyond the sudden state approximation. In particular, we find that a descri

This paper investigates the impact of rating agencies in a market with asymmetric information. In particular, the role of credit rating agencies as an intermediary between investors and bond issuers is discussed. We model this setting in a dynamic framework in which both rating agencies and bond issuers are of heterogeneous quality. Rating agencies can apply costly research technology to reveal th

We develop an agent-based model in which heterogeneous and boundedly rational agents interact by trading a risky asset at an endogenously set price. Agents are endowed with balance sheets comprising the risky asset as well as cash on the asset side and equity capital as well as debt on the liabilities side. A number of findings emerge when simulating the model: we find that the empirically observa

This paper presents a Heterogeneous Agent Model of a financial market with chartist and fundamentalist traders that exhibit bounded rationality and short-term thinking to explain the effect of under and overreaction to news. The existence of the Market Maker’s finite price adjustment speed and the presence of risk aversion lead to the fact that prices do not adjust instantaneously to new informati

Even though Sweden stands out in many ways, with for example a well-developed welfare system, there are some indications that Swedish egalitarianism does not include tolerance for people with low income. The present research concerns the content of the Swedish stereotype of poor people, and examines whether the poor are associated with just as negative traits as they are in other countries. Three Even though Sweden stands out in many ways, with for example a well-developed welfare system, there are some indications that Swedish egalitarianism does not include tolerance for people with low income. The present research concerns the content of the Swedish stereotype of poor people, and examines whether the poor are associated with just as negative traits as they are in other countries. Three

Interference effects in quantum dots between different transport channels can lead to a strong suppression of conductance, which cuts like a canyon through the common conductance plot [Phys. Rev. Lett. 104, 186804 (2010)PRLTAO0031-900710.1103/PhysRevLett.104.186804]. In the present work we consider the thermoelectric transport properties of the canyon of conductance suppression using the second-or

Solving process problem needs the support of method and knowledge. To organize relative resources in accordance with requirement, an innovative process design service model based on service-oriented architecture was proposed. Strategy service and knowledge service were built from the dimensions of knowledge, method and computer aided tool. The ontology of services was built, and the system archite

We theoretically investigate nonlinear ballistic thermoelectric transport in a superlattice-structured nanowire. By a special choice of nonuniform widths of the superlattice barriers - analogous to antireflection coating in optical systems - it is possible to achieve a transmission which comes close to a square profile as a function of energy. We calculate the low-temperature output power and powe

In order to achieve significant improvements in road safety at the national level, there is a need for a systematic approach to road safety management with clear responsibilities and accountability. In this paper – after a review of the literature on guidelines, recommendations and research findings – twelve essential elements of such a systematic approach is pointed out, and corresponding relevanIn order to achieve significant improvements in road safety at the national level, there is a need for a systematic approach to road safety management with clear responsibilities and accountability. In this paper – after a review of the literature on guidelines, recommendations and research findings – twelve essential elements of such a systematic approach are pointed out, and corresponding releva

We examine the capacity of artificial biomolecular networks to respond to perturbations with structurally signed steady-state changes. We consider network architectures designed to balance their output production as a function of downstream demand: the species producing the output, called a source, up- or down-regulates its production rate as a function of the demand. Using an exact algorithm we s

We study diffusion of cooperation in a two-population game in continuous time. At each instant, the game involves two random individuals, one from each population. The game has the structure of a Prisoner's dilemma where each player can choose either to cooperate (c) or to defect (d), and is reframed within the field of approachability in two-player repeated game with vector payoffs. We turn the g

Massive MIMO is a promising technology for the coming 5G wireless systems. In this paper, a programmable baseband processor specifically designed for uplink symbol detection targeting massive MIMO is presented with a novel matrix inversion method proposed to obtain more precise and efficient computation. Including a microcode controlled channel preprocessing unit and a pipelined detection unit, th