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Stråket mellan E4:an och Kolmårdens djurpark är den primära tillfartsvägen till Kolmårdens djurpark och passerar genom tätorten Krokek. De huvudsakliga problemen som identifierats är att en stor andel resor till djurparken sker med bil och att förutsättningarna för säker gång- och cykeltrafik längs Strandvägen och utredningsstråket är bristande. Framkomligheten för boende är begränsad under djurparkens högsäsong och kollektivtrafiken har svårt att hålla tidtabellen. Dessa problem bedöms öka i takt med att Krokek växer och att antalet besökare till Kolmårdens djurpark ökar. Bristbeskrivningen baseras i huvudsak på information som delgivits av föreningar, organisationer, verksamheter som är verksamma i stråket på ett dialogmöte samt brister som uppdagats i tidigare planeringsunderlag och inkomna synpunkter från Trafikverket, Norrköpings kommun, Östgötatrafiken, Kolmårdens djurpark och Region Östergötland. Syftet med åtgärdsvalstudien är att finna åtgärdsförslag som avhjälper de brister som framkommit under processen och som lyfts i länstransportplanen 2018–2029. Åtgärderna ska förbättra trafiksituationen avseende tillgänglighet, trafiksäkerhet och trygghet och ge förutsättningar för kommunens bebyggelseutveckling.

This thesis is based on nine papers, all concerned with parameter estimation. The thesis aims at solving problems related to real-world applications such as spectroscopy, DNA sequencing, and audio processing, using sparse modeling heuristics. For the problems considered in this thesis, one is not only concerned with finding the parameters in the signal model, but also to determine the number of signal components present in the measurements. In recent years, developments in sparse modeling have allowed for methods that jointly estimate the parameters in the model and the model order. Based on these achievements, the approach often taken in this thesis is as follows. First, a parametric model of the considered signal is derived, containing different parameters that capture the important characteristics of the signal. When the signal model has been determined, an optimization problem is formed aimed at finding the parameters in the model as well as the model order. An important aspect when formulating the optimization problem is to include the characteristics and properties inherent in the signal model. For instance, if we know that the true set of parameters are smooth, this should also be a requirement reflected in the optimization problem. In the ideal case, the optimization problem is convex, in which case powerful solvers exist that may be used for finding the solution. In many cases, however, the original optimization problem is rather complex and definitely not convex. In this case, a common approach is to use a convex relaxation that approximates the original problem. In papers A, B, C, E, F, and H, this approach is utilized, however in different variations and for different applications. Paper A deals with estimation of periodic signals in symbolic sequences used in DNA sequences, paper B looks at the estimation of multi-dimensional sinusoids for NMR data, paper C considers the estimation of an unknown number of chirps for audio signals, papers E and F study pitch estimation, where the first paper considers online estimation and where the second paper proposes an off-grid method. Paper D proposes a generalization of a popular estimation method, whereas paper G introduces a new approach to frequency estimation. Paper I investigates how to sample a partially know signal to minimize the number of samples needed given a lower bound on the desired estimation performance. In all papers, the proposed methods are examined using simulated and/or measured data and compared to competing state-of-the-art methods.

In this work, we propose a computationally efficient algorithm for estimating multi-dimensional spectral lines. The method treats the data tensor's dimensions separately, yielding the corresponding frequency estimates for each dimension. Then, in a second step, the estimates are ordered over dimensions, thus forming the resulting multidimensional parameter estimates. For high dimensional data, the proposed method offers statistically efficient estimates for moderate to high signal to noise ratios, at a computational cost substantially lower than typical non-parametric Fourier-transform based periodogram solutions, as well as to state-of-the-art parametric estimators.

South Polar Skua is a seabird feeding on both marine resources and on other seabirds’ egg and chicks. There are few studies investigating South Polar Skua space use during breeding season and how it is affected by sex or phenology. This study was carried out during the breeding season 2012-2013 at Svarthammaren in Dronning Maud Land (71° 53′ S, 05° 10′ E). 56 GPS loggers were used to track 48 individuals during incubation and chick rearing period of skua and petrel. At Svarthammaren, South Polar Skua use petrels as their only available food resource with no competitors. We investigated how sex and phenology (skua and petrel incubation and chick rearing periods) affected South Polar Skuas main activities, such as hunting effort (i.e., area used in the petrel colony), time spent on nest defense, and bathing activity. Indeed, petrels defend themselves by spitting oil on their attackers, which affects feathers and flight ability of skua. Skua time budgets depended on prey phenology and differed between sexes. During petrel incubation time, females spent more time around the nest area than males and both skua partners had higher bathing activity during petrel chick-rearing period. Both sexes invested more in hunting effort during the chick-rearing period compared to incubation. The results were mostly in line with previous studies, that skua chick phenology affects their hunting effort and skua had higher bathing activity when they were more exposed for oily attacks. However, we also found that prey phenology affected on skua nest attendance to higher degree than expected, which we believed were based on prey availability.

Resultatkontrollen for 2002 viser at arealet som forynges naturlig og ved planting holder seg relativt stabilt sammenliknet med årene før. For 2002 er arealet avvirket ved snauhogst 64%. Dette er på samme nivå som de foregående årene.

The paper summarizes the methodical work preceding the introduction of the Sixth National Forest Survey of Sweden. Both theoretical and practical problems are considered. Thus the paper contains a discussion about permanent plots and describes the variables recorded, the data acquisition system, some results from field tests and the statistical considerations behind the new design.