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There is a need for mathematical modelling for the evaluation of important parameters for photon imaging systems. A Monte Carlo program which simulates medical imaging nuclear detectors has been developed. Different materials can be chosen for the detector, a cover and a phantom. Cylindrical, spherical, rectangular and more complex phantom and source shapes can be simulated. Photoelectric, incoher

This work concentrates on automatic procedures for simplifying chemical models for realistic fuels using skeletal mechanism construction and Quasi Steady-State Approximation (QSSA) applied to detailed reaction mechanisms. To automate the selection of species for removal or approximation, different indices for species ranking have thus been proposed. Reaction flow rates are combined with sensitivit

We present two new methods for finding a lowest common ancestor (LCA) for each pair of vertices of a directed acyclic graph (dag) on n vertices and m edges. The first method is surprisingly natural and solves the all-pairs LCA problem for the input dag on n vertices and m edges in time 0 (n m). The second method relies on a novel reduction of the all-pairs LCA problem to the problem of finding max

This paper investigates the performance of reduced-state trellis-based intersymbol interference equalizers, which are based on the so-called Ungerboeck and Forney observation models. Although the two models are equivalent when an optimum equalizer is employed, their performances differ significantly when using reduced-complexity methods. It is demonstrated that practical equalizers operating on th

This report describes technical improvements to the manufacture of a carbon fibre electrode for the stable and sensitive detection of H2O2 (detection limit at 0.5 mu M). This electrode was also modified through the co-immobilisation of acetylcholinesterase (AChE) and/or choline oxidase (ChOx) in a bovine serum albumin (BSA) membrane for the development of a sensor for in vivo measurements of acety

Popular Abstract in Swedish Uppsatsskrivningen i läroverket har ofta beskrivits på ett negativt sätt: ensidig ämnesgivning, onaturliga skrivsituationer och bristfällig förberedande undervisning. Syftet med denna avhandling är att ta reda på om denna bild av praktiken haft en motsvarighet i teorin eller om det i stället funnits mer ambitiösa och varierade mål för skrivträningen. De material som redThis dissertation is about the goals that existed for Swedish essay writing in grammar schools from the start of the nineteenth century to the 1960s. The point of departure is the contrast between the negative image often painted of this essay writing and the positive picture painted of writing tuition before this period (classical rhetoric) and after it (process-oriented writing with the emphasis

For a random walk with negative mean and heavy-tailed increment distribution F, it is well known that under suitable subexponential assumptions, the distribution pi of the maximum has a tail pi(x, infinity) which is asymptotically proportional to integral(x)(infinity)F(y,infinity) dy. We supplement here this by a local result showing that pi(x, x + z] is asymptotically proportional to zF(x,infinit

National goals regarding sustainable development from the Swedish government were decisive in the planning process when the newly built city district Western Harbour was established in the city of Malmo, Sweden. A systems analysis was used as a tool for evaluating different collection and treatment systems. This type of analysis does not include more subjective factors such as acceptance of organi

Impaired appetite and weight changes are commonly seen in patients with depression, but the pathophysiology behind this imbalance between energy intake and energy expenditure remains largely unknown. The aim of this paper is to review the literature regarding a possible role for cytokines in the regulation of appetite and body weight, with special emphasis on depression. There now exists a substan

A model-independent search for deviations from the Standard Model prediction is performed in e(+) p and e(-) p collisions at HERA using H1 data corresponding to an integrated luminosity of 117 pb(-1). For the first time all event topologies involving isolated electrons, photons, muons, neutrinos and jets with high transverse momenta are investigated in a single analysis. Events are assigned to exc

This paper suggests sufficient conditions for asymptotically stable dynamical output feedback controller design based on the circle criterion. It is shown that a dynamic output feedback stabilization problem with impending problems of finite escape time, previously attacked by observer-based design, can be successfully solved using circle criterion design. Stability of the closed-loop system is gl

Various occupational exposures have been monitored by chromosomal aberrations, sister chromatid exchanges and micronuclei in peripheral blood lymphocytes. During the last decade, epidemiological studies have evaluated whether any of these markers foreshadows cancer risk. Results from Nordic, Italian and Czech cohorts support an approximately twofold cancer risk among subjects with high frequencies

Results from the application of a modified dual photopeak window scatter correction method to Monte Carlo simulated Tl-201 emission images are presented. In the Monte Carlo investigation, individual simulations are performed for six radiation emissions of Tl-201. For each emission, point sources of Tl-201 are imaged at various locations in a water-filled elliptical tub phantom using three energy w