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This thesis collects contributions to wireline and wireless communication systems with an emphasis on multiuser and multicarrier physical layer technology. To deliver increased capacity, modern wireline access systems such as G.fast extend the signal bandwidth up from tens to hundreds of MHz. This ambitious development revealed a number of unforeseen hurdles such as the impact of impedance changes

In many data processing tasks, declarative query programming offers substantial benefit over manual data analysis: the query processors found in declarative systems can use powerful algorithms such as query planning to choose high-level execution strategies during compilation. However, the principal downside of such languages is that their primitives must be carefully curated, to allow the query p

Modern software development relies on code reuse, which software engineers typically realise through handwritten abstractions, such as functions, methods, or classes. However, such abstractions can be challenging to develop and maintain. One alternative form of re-use is copy-paste-modify, a methodology in which developers explicitly duplicate source code to adapt the duplicate for a new purpose.

We introduce the concept of residual investigation for program analysis. A residual investigation is a dynamic check installed as a result of running a static analysis that reports a possible program error. The purpose is to observe conditions that indicate whether the statically predicted program fault is likely to be realizable and relevant. The key feature of a residual investigation is that it

BACKGROUND AND OBJECTIVES: ABO remains the clinically most important blood group system, but despite earlier extensive research, significant findings are still being made. The vast majority of catalogued ABO null alleles are based on the c.261delG polymorphism. Apart from c.802G>A, other mechanisms for O alleles are rare. While analysing the data set from the 1000 Genomes (1000G) project, we encou

This paper presents achievable uplink (UL) sum-rate predictions for a measured line-of-sight (LOS) massive multiple-input, multiple-output (MIMO) (MMIMO) scenario and illustrates the trade-off between spatial multiplexing performance and channel de-coherence rate for an increasing number of base station (BS) antennas. In addition, an orthogonal frequency division multiplexing (OFDM) case study is

We have developed a phenomenological effective quantum-field theoretical model describing the "hadron gas" of the lightest pseudoscalar mesons, scalar σ-meson and σ-vacuum, i.e. the expectation value of the σ-field, at finite temperatures. The corresponding thermodynamic approach was formulated in terms of the generating functional derived from the effective Lagrangian providing the basic thermody

Context. There have been conflicting results with respect to the extent that radial migration has played in the evolution of the Galaxy. Additionally, observations of the solar neighborhood have shown evidence of a merger in the past history of the Milky Way that drives enhanced radial migration. Aims. We attempt to determine the relative fraction of stars that have undergone significant radial mi

In this work, we propose a method for finding an optimal, non-uniform, sampling scheme for a general class of signals in which the signal measurements may be non-linear functions of the parameters to be estimated. Formulated as a convex optimization problem reminiscent of the sensor selection problem, the method determines an optimal sampling scheme given a suitable estimation bound on the paramet

The 2014 Swedish National infrastructure plan allocated funds to implement a “Regional Superbus concept”. The concept involves the upgrading a number of existing regional express bus services to make them function as an alternative to investing in regional rail. The Regional superbus concept is an attempt to adapt the BRT planning philosophy to the regional scale and the context of the region it s

This paper examines the short-term effect between take-up of Social Assistance Benefit (SAB) and mental health. Using a panel dataset including rich yearly register data on e.g. income, income sources, unemployment and types of pharmaceutical consumption for over 140,000 Swedes 2006-2012, we quantify the importance of the psychosocial dimensions (e.g. shame and guilt) of the socioeconomic status –

This paper employs Swedish data on households' stock holdings to investigate how consumption responds to changes in stock market returns. We instrument the actual capital gains and dividend payments with past portfolio weights. Unrealized capital gains lead to a marginal propensity to consume (MPC) of 13 percent for the bottom 50% of the wealth distribution, but a flat 5 percent for the rest of th

This paper examines the effect of competition on a firm's choice of opening hours in the motor vehicle inspection market. Competition affects the incentive inspection firms face when choosing opening hours, which influences the probability that consumers find service time that best matches their preferred time. We use 2SLS analyses to resolve the potential endogeneity of market entry decisions. Us

We examine the impact of competition on a firm's incentive to relax the standards of its inspection to its customers in the Swedish motor vehicle inspection market, which is heavily regulated and consciously designed to mitigate incentives to deviate from the regulation. We use a panel dataset representing 22.5 million car roadworthiness tests during the period 2010--2015. Fixed effects and instru

This paper provides sufficient conditions under which convex monotonic evolutionary dynamics (a class of imitative dynamics that includes the replicator dynamic) select against strategies that do not survive iterated elimination of weakly dominated strategies. We apply these conditions to Bertrand duopolies, first-price auctions, finitely repeated Prisoner's Dilemmas, and the p-Beauty Contests. Ou

This study examines the effects of super-fast internet connections on the academic achievement of students in upper secondary school. We link detailed register data on around 250,000 students to local levels of access to optic fiber broadband, in order to estimate a causal effect of broadband on student GPA. We show that reaching full coverage in the student’s parish of residence causes a GPA redu