APARCH Models Estimated by Support Vector Regression

This thesis presents a comprehensive study of asymmetric power autoregressive conditional heteroschedasticity (APARCH) models for modelling volatility in financial return data. The goal is to estimate and forecast volatility in financial data with excess kurtosis, volatility clustering and asymmetric distribution. Models based on maximum likelihood estimation (MLE) will be compared to the kernel based support vector regression (SVR). The popular Gaussian kernel and a wavelet based kernel will be used for the SVR. The methods will be tested on empirical data, including stock index prices, credit spreads and electric power prices. The results indicate that asymmetric power models are needed to capture the asseymtry in the data. Furthermore, SVR models are able to improve estimation and forecasting accuracy, compared with the APARCH models based on MLE.Masteroppgave i statistikkSTAT399MAMN-STA

Evalueringsrapport : politiets innsats : øvelse Gemini 2012

Gemini er en årlig samvirkeøvelse mellom politiet, Forsvaret og operatørselskap(er) på norsk kontinentalsokkel. Hensikten med øvelsen er å trene sivile og militære enheter i kontra-terror aksjon mot innretning til havs som ledd i den generelle beredskap for sikring av olje- og gassinstallasjonene på norsk kontinentalsokkel. Den taktiske håndteringen av slike hendelser skal håndteres av spesialstyrker fra politiet og Forsvaret. Øvelse Gemini er også en bistandsøvelse, hvor Forsvaret trener bistand til politiet. Terrorisme er kriminalitet som politiet har ansvaret for å forebygge, bekjempe og etterforske, og operasjonen ledes derfor av stedlig politimester (PM). Den primære målgruppen for øvelsen er det taktiske (utøvende) nivået. Politiet og Forsvaret øver jevnlig sammen både nasjonalt og lokalt. Øvelse Gemini 2012 er likevel spesiell i den forstand at den er den første store samvirkeøvelsen etter hendelsene 22. juli 2011

Fast and optimal broad-band Stokes/Mueller polarimeter design by the use of a genetic algorithm

A fast multichannel Stokes/Mueller polarimeter with no mechanically moving parts has been designed to have close to optimal performance from 430-2000 nm by applying a genetic algorithm. Stokes (Mueller) polarimeters are characterized by their ability to analyze the full Stokes (Mueller) vector (matrix) of the incident light. This ability is characterized by the condition number, $\kappa$, which directly influences the measurement noise in polarimetric measurements. Due to the spectral dependence of the retardance in birefringent materials, it is not trivial to design a polarimeter using dispersive components. We present here both a method to do this optimization using a genetic algorithm, as well as simulation results. Our results include fast, broad-band polarimeter designs for spectrographic use, based on 2 and 3 Ferroelectric Liquid Crystals, whose material properties are taken from measured values. The results promise to reduce the measurement noise significantly over previous designs, up to a factor of 4.5 for a Mueller polarimeter, in addition to extending the spectral range.Comment: 10 pages, 6 figures, submitted to Optics Expres

Evaluation of the proliferation markers Ki-67/MIB-1, mitosin, survivin, pHH3, and DNA topoisomerase IIα in human anaplastic astrocytomas - an immunohistochemical study

<p>Abstract</p> <p>Background</p> <p>Histological malignancy grading of astrocytomas can be challenging despite criteria given by the World Health Organisation (WHO). Grading is fundamental for optimal prognostication and treatment, and additional biomarkers are needed to support the histopathological diagnosis. Estimation of proliferative activity has gained much enthusiasm, and the present study was designed to evaluate and compare novel immunohistochemical proliferative markers in human anaplastic astrocytomas.</p> <p>Methods</p> <p>Proliferative activity was determined in twenty-seven cases with antibodies reactive against the Ki-67 antigen, mitosin, survivin, pHH3, and DNA topoisomerase IIα, and they were mutually compared as well as related to mitotic activity.</p> <p>Results</p> <p>The markers correlated well with each other, but poorly with mitoses, probably because of small and squeezed tumour samples, in which identification of mitoses can be difficult. Positive association to overall survival was observed as well.</p> <p>Conclusions</p> <p>Our data show that these markers may assist significantly in the evaluation of proliferative activity in anaplastic astrocytomas and even have prognostic value.</p

Kvalitet i barnehagelærerutdanning i naturvitenskap: En fellesnordisk studiemodul

This article presents a new joint Nordic study module consisting of a theoretical framework, the kindergarten teacher students’ case study and a reflection talk, in natural science for the kinder-garten teacher education. The module is developed through an interdisciplinary collaboration in the Nordplus network: Learning of science concepts by kindergarten children: Nordic study module for the kindergarten teacher education (NATGREP), with science and quality in the kindergarten teacher education in focus. The introduction describes the Nordic kindergartens shortly, and concepts as quality and competence are shortly discussed. It is followed by the module’s theoretical framework. Then the study module’s development process is described accompanied by reflections of the student’s case studies in relation to the theoretical framework. At the end, the work with the study module is summarised, and the main conclusion is that the study module contributes positively to the students’ skills development, both in science and quality

Ki-67 expression is superior to mitotic count and novel proliferation markers PHH3, MCM4 and mitosin as a prognostic factor in thick cutaneous melanoma

<p>Abstract</p> <p>Background</p> <p>Tumor cell proliferation is a predictor of survival in cutaneous melanoma. The aim of the present study was to evaluate the prognostic impact of mitotic count, Ki-67 expression and novel proliferation markers phosphohistone H3 (PHH3), minichromosome maintenance protein 4 (MCM4) and mitosin, and to compare the results with histopathological variables.</p> <p>Methods</p> <p>202 consecutive cases of nodular cutaneous melanoma were initially included. Mitotic count (mitosis per mm²) was assessed on H&E sections, and Ki-67 expression was estimated by immunohistochemistry on standard sections. PHH3, MCM4 and mitosin were examined by staining of tissue microarrays (TMA) sections.</p> <p>Results</p> <p>Increased mitotic count and elevated Ki-67 expression were strongly associated with increased tumor thickness, presence of ulceration and tumor necrosis. Furthermore, high mitotic count and elevated Ki-67 expression were also associated with Clark's level of invasion and presence of vascular invasion. High expression of PHH3 and MCM4 was correlated with high mitotic count, elevated Ki-67 expression and tumor ulceration, and increased PHH3 frequencies were associated with tumor thickness and presence of tumor necrosis. Univariate analyses showed a worse outcome in cases with elevated Ki-67 expression and high mitotic count, whereas PHH3, MCM4 and mitosin were not significant. Tumor cell proliferation by Ki-67 had significant prognostic impact by multivariate analysis.</p> <p>Conclusions</p> <p>Ki-67 was a stronger and more robust prognostic indicator than mitotic count in this series of nodular melanoma. PHH3, MCM4 and mitosin did not predict patient survival.</p

Tumor necrosis is associated with increased alphavbeta3 integrin expression and poor prognosis in nodular cutaneous melanomas

<p>Abstract</p> <p>Background</p> <p>Tumor necrosis and apoptotic activity are considered important in cancer progression, but these features have not been much studied in melanomas. Our hypothesis was that rapid growth in cutaneous melanomas of the vertical growth phase might lead to tissue hypoxia, alterations in apoptotic activity and tumor necrosis. We proposed that these tumor characteristics might be associated with changes in expression of cell adhesion proteins leading to increased invasive capacity and reduced patient survival.</p> <p>Methods</p> <p>A well characterized series of nodular melanoma (originally 202 cases) and other benign and malignant melanocytic tumors (109 cases) were examined for the presence of necrosis, apoptotic activity (TUNEL assay), immunohistochemical expression of hypoxia markers (HIF-1 α, CAIX, TNF-α, Apaf-1) and cell adhesion proteins (α_vβ₃integrin, CD44/HCAM and osteopontin). We hypothesized that tumor hypoxia and necrosis might be associated with increased invasiveness in melanoma through alterations of tumor cell adhesion proteins.</p> <p>Results</p> <p>Necrosis was present in 29% of nodular melanomas and was associated with increased tumor thickness, tumor ulceration, vascular invasion, higher tumor proliferation and apoptotic index, increased expression of α_vβ₃integrin and poor patient outcome by multivariate analysis. Tumor cell apoptosis did also correlate with reduced patient survival. Expression of TNF-α and Apaf-1 was significantly associated with tumor thickness, and osteopontin expression correlated with increased tumor cell proliferation (Ki-67).</p> <p>Conclusion</p> <p>Tumor necrosis and apoptotic activity are important features of melanoma progression and prognosis, at least partly through alterations in cell adhesion molecules such as increased α_vβ₃integrin expression, revealing potentially important targets for new therapeutic approaches to be further explored.</p

Seismic characterization of lower cretaceous clastic wedges in the Tromsø Basin

Master's thesis in Petroleum engineeringIn this study, seismic reflection, well logs and core data has been used to characterize Lower Cretaceous marine to deep marine syn-rift clastic wedges in the southwestern Barents Sea. The study area is situated on a faulted terrace towards the Tromsø Basin away from the Finnmark Platform. The terrace is confined an intersection between three major fault zones which confines the structure. The structure is heavily segmented, generating sub-terraces and along strike depocenters towards the Tromsø Basin. Three main fault families are controlling the paleodrainage, in which two are controlling the sediment dispersal into the structure and one is controlling the distribution of sediments. Seismic characterization reveals three seismic facies, from chaotic low amplitude to continuous high amplitude reflections. Characterization from the seismic reveals several depositional environments, in which one of the seismic facies penetrated and controlled by well data. Three main lithofacies have been distinguished in core, and consists of heterolithic mudstones, debris flows and high density turbidites

Validation of a wind farm wake model based on the actuator disc concept in complex terrain

A wind turbine operating downwind of another will stand in the wake of the upstream turbine, resulting in decreased power generation and increased load fatigue. In order to keep wake losses at a minimum, wind farm designers rely on wake models to optimize the wind farm layout. Therefore, accurate wind turbine wake aerodynamic modelling is essential for developing cost efficient modern wind farms, that consists of a large number of wind turbines usually congregated in compact formation. Using large sets of SCADA data, which are, on-site measurements data from full scale wind turbines and meteorological data from a wind farm located in complex terrain in the northern part of Norway, the aim of this study was to perform a comparative analysis of the newly developed numerical wake model referred to as the actuator disc method (ACD), against the two most commonly known analytical wake models namely the Jensen- and Larsen model. The simulations were performed in the state of the art Computational Fluid Dynamics (CFD) software, WindSim, which solves the Reynolds Averaged Navier-Stokes (RANS) equations for wind farm development purposes. Results of this study showed that the ACD and Larsen wake model outperformed the Jensen model for most single wake cases. For multiple wake cases, the ACD method was found to provide the most accurate results, by capturing wake-wake and wake-terrain effect. All three wake models overestimated the wake losses for the uncalibrated results in both single and multiple wake cases. However, Due to the poor quality in measurement data discovered during this study, no clear-cut conclusion can be drawn on to which wake model performed best. The main conclusion drawn in this study emphasises the necessity of high quality measurement data for wake model validation purposes.M-FORN