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Popular Abstract in Swedish Ekonomiska och miljömässiga problem gör det svårt att bygga ut kraftledningsnätet i samma takt som efterfrågan på elenergi ökar. Ett alternativ är att öka belastningen av befintliga kraftledningar på bekostnad av de säkerhetsmarginaler som finns. En av flera dimensionerande faktorer är risken för otillräckligt dämpade effektpendlingar mellan generatorer i kraftsystemet.Environmental and economical aspects make it difficult to build new power lines and to reinforce existing ones. The continued growth in demand for electric power must therefore to a great extent be met by increased loading of available lines. A consequence is that power system damping is reduced, leading to a risk of poorly damped power oscillations between the generators. This thesis proposes the

Anders Nygrens ambition was to develop a criterion by which he could distinguish between science and non-science. This is th K(v) of Nygren. According to Nygreb tgere are three ways of arguing in science which all fullfill the demand of K(v): a) deductive argumentation b) empirical argumentation and c) philosophical argumentation. a) and b) operate at the material level and c) at the formal one. c

The period from 1910 to 1930 was a time when a number of theoretical systems saw the light of the day in Central Europe: psychoanalysis, neopositivism, phenomenology, the Warsaw School of logic, Gestalt-psychology and the structuralism of the Prague School of Linguistics. The Prague School arose in the liberal-minded Prague of the 1920s and came to have an enormous influence on multiple fields wit

Problem statement. Despite their success-story, neural networks have one major disadvantage compared to other techniques: the inability to explain comprehensively how a trained neural network reaches its output; neural networks are not only (incorrectly) seen as a “magic tool” but possibly even more as a mysterious “black box” [1]. This is an important aspect of the functionality of any technology

Within the academic debate attempts have been made at combining the resource based view and the activities based view (C.f. Mathews, 2006). Among the calls for such attempts we find Haanes and Fjeldstad (2000) who point out that there is a need for integrating the activity based view and the resource based view, with a particular focus on competences. The view of activities as associated with comp

Stochastic leaky integrate-and-fire (LIF) neuronal models are common theoretical tools for studying properties of real neuronal systems. Experimental data of frequently sampled membrane potential measurements between spikes show that the assumption of constant parameter values is not realistic and that some (random) fluctuations are occurring. In this article, we extend the stochastic LIF model, a

Kraft black liquor lignin is a biofuel that is separated from the cellulose during kraft pulping. Improved technology and energy integration in paper mills have led to an energy surplus at many mills. It is therefore of great interest to extract the lignin from the pulp mill and sell it as fuel to replace fossil fuel in other furnaces. The fractionation of kraft black liquor with a total dry matte

The creation of 3D scaffolds that mimic the structure of physiological tissue required for normal cell function is a major bioengineering challenge. For corneal stroma reconstruction this necessitates the creation of a stroma-like scaffold consisting of a stack of orthogonally disposed sheets of aligned collagen fibrils. This study demonstrates that such a scaffold can be built up using magnetic a

The most prominent of the two major global delta C-13 excursions in the Ordovician, the Hirnantian delta C-13 excursion (HICE), which is previously recorded from the uppermost Ordovician in a few sections in Nevada, Quebec, Arctic Canada, Baltoscandia, Scotland and China, is documented for the first time from the North American Midcontinent. Samples through the Girardeau Limestone and Leemon Forma

Causality tests in the Granger's sense are increasingly applied in empirical research. Since the unit root revolution in time-series analysis, several modifications of tests for causality have been introduced in the literature. One of the recent developments is the Toda-Yamamoto modified Wald (MWALD) test, which is attractive due to its simple application, its absence of pre-testing distortions, a

Simple and computer attractive models for calculating radiation properties are still needed. This paper gives correlations for the Planck and Rosseland means of the extinction and scattering coefficients for both cylindrically and spherically shaped soot particles. The means are valid for temperatures between 400 and 2400 K and particle radii between 0.001 and 0.5 mum. The errors of these means ar

This article summarizes our most recent contributions to the rapidly growing field of supported lipid assemblies with emphasis on current studies addressing both fundamental and applied aspects of supported lipid bilayer (SLB) and tethered lipid vesicles (TLVs) to be utilized in sensing applications. The new insights obtained from combining the quartz crystal microbalance with dissipation monitori