This thesis consists of eight studies that cover topics in the increasingly influential field of futures- commodities, macroeconomic volatility and financial development. Chapter 2 considers the case of Argentina and provides a first thorough examination of the timing of the Argentine debacle. By applying a group of econometric tests for structural breaks on a range of GDP growth series over a period from 1886 to 2003 we conclude that there are two key dates in Argentina's economic history (1918 and 1948) that need to be inspected closely in order to further our understanding of the Argentine debacle. Chapters 3 and 4 investigated the time-varying link between financial development and economic growth. By employing the logistic smooth transition framework to annual data for Brazil covering the period 1890-2003 we found that financial development has a mixed (either positive or negative) time- varying effect on growth, which depends on trade openness thresholds. We also find a positive impact of trade openness on growth while a mainly negative one for the various political instability measures. Chapter 5 studied the convergence properties of inflation rates among the countries of the European Monetary Union over the period 1980-2013. By applying recently developed panel unit root/stationarity tests overall we are able to accept the stationarity hypothesis. Similarly, results from the univariate testing procedure indicated a mixed evidence in favour of convergence. Hence next we employ a clustering algorithm in the context of multivariate stationarity tests and we statistically detect three absolute convergence clubs in the pre-euro period, which consist of early accession countries. We also detect two separate clusters of early accession countries in the post-1997 period. For the rest of the countries/cases we find evidence of divergent behaviour. For robustness check we additionally employ a pairwise convergence Bayesian framework, which broadly confirms our findings. Finally, we show that in the presence of volatility spillovers and structural breaks time-varying persistence will be transmitted from the conditional variance to the conditional mean. Chapter 6 focuses on the negative consequences that the five years of austerity (2010-2014) imposed on the Greek economy and the society in general. To achieve that goal we summarize the views of three renowned economists, namely Paul De Grauwe, Paul Krugman and Joseph Stiglitz on the eurozone crisis as well as the Greek case. In support of their claims we provide solid evidence of the dramatic effects that the restrictive policies had on Greece. Chapter 7 analyzes the properties of inflation rates and their volatilities among five European countries over a period 1960-2003. Unlike to previous studies we investigate whether or not the infl ation rate and its volatility of each individual country displayed time-varying characteristics. By applying various power ARCH processes with structural breaks and with or without in-mean effects the results indicated that the conditional means, variances as well as the in-mean effect displayed time-varying behaviour. We also show that for France, Italy and Netherlands the in-mean effect is positive, whereas that of Austria and Denmark is negative. Chapter 8 examines the stochastic properties of different commodity time series during the recent fi nancial and EU sovereign debt crisis (1997-2013). By employing the Bai-Perron method we detect five breaks for each of the commodity returns (both in the mean and in the variance). The majority of the breaks are closely associated with the two aforementioned crises. Having obtained the breaks we estimated the power ARCH models for each commodity allowing the conditional means and variances to switch across the breakpoints. The results indicate overall that there is a time-varying behaviour of the conditional mean and variance parameters in the case of grains, energies and softs. In contrast, metals and soya complex show time-varying characteristics only in the conditional variance. Finally, conducting a forecasting analysis using spectral techniques (in both mapped and unmapped data) we find that the prices of corn remained almost stable while for wheat, heating oil, wti and orange juice the prices decreased further, though slightly. In the case of natural gas, coffee and sugar overall the prices experienced significant defl ationary pressures. As far as the prices of oats, platinum, rbob, cocoa, soybean, soymeal and soyoil is concerned, they showed an upward trend. Chapter 9 examines the effect of health and military expenditures, trade openness and political instability on output growth. By employing a pooled generalised least squares method for 19 NATO countries from 1993 to 2010 we fi nd that there is a negative impact of health and military expenditures, and political instability on economic growth whereas that of trade openness is positive.

Diploma thesis deals with numerical simulations of an air flow in a water cooled charge air cooler (WCAC), specifically with pressure drops in inlet/outlet chamber. The simulations have been performed in a proprietary software Star-CCM+. Physical phenomena have been solved by the Reynolds-averaged Navier-Stokes (RANS) equations and consequently a matrix of pressure drops for miscellaneous variations of chamber's geometry and the initial flow conditions has been created. Based on the CFD results, dependence between calculated pressure drops and changing parameters has been analyzed and finally a 1D solver has been developed and implemented into a software OpenModelica.

No description available.

The use of advanced functional polymer materials has gained an enormous impact during the past decades. Due to the fact that the physical properties of macromolecules are inherently dependent on their structure and connectivity on the nanoscale, precisely control over polymer architecture has been a longstanding goal for polymer chemists. The recent development of copper catalyzed azide-alkyne click chemistry provides a nearly quantitatively tool for macromolecular coupling. Through the combination of living polymerization and click chemistry, novel complex polymer architectures can be readily constructed, including star polymers, brush polymers, cyclic polymer and ladder polymers. While amphiphilic block copolymers have demonstrated their utility for a range of practical applications, the behavior of block copolymers that contain cyclic topologies remains largely unexplored due to limited synthetic access. In order to investigate their micelle formation, biocompatible cyclic amphiphilic poly(ethylene glycol)-block-polycaprolactone, c-(PEG-b-PCL), and tadpole shaped PEG-PCL, were synthesized by a combination of ring opening polymerization (ROP) and click chemistry. In addition, exactly analogous linear block copolymers have been prepared as control samples to elucidate the role of polymer architecture in their self-assembly and acid-catalyzed degradation. High purity homo-arm and mikto-arm poly(ethylene glycol) (PEG) stars were successfully prepared by the combination of epoxide ring openings and azide-alkyne click reactions. First, monohydroxy-PEG was modified via epoxide chemistry to bear one hydroxyl and one azide functionality at the same polymer chain end. An alkyne functionalized PEG chain was then coupled to the azide. Subsequently, the remaining hydroxyl could be reactivated by epoxide chemistry again to an azide and alcohol group. This enabled a step-wise coupling and reactivation of the end group to add a series of well-defined polymer arms onto a star polymer. The use of efficient reactions for this iterative route provided star polymers with an exact number of arms, and a tailorable degree of polymerization for each arm. Detailed characterization confirmed the high purity of multi-arm polyethylene glycol products. Novel cyclic brush-shaped polymers can be successfully prepared by using the CuAAC click coupling reaction. First, cyclic-shaped polymer bearing a single hydroxyl group can be synthesized by CuAAC click cyclization. After a one-step modification of the hydroxyl group by esterification with an azido-carboxylic acid, a “clickable†polymer ring was obtained. A linear polymer backbone with an alkyne functional group on every repeat unit was prepared by ATRP of acetoxystyrene followed by reduction to poly(4-hydroxystyrene) and esterification with pentynoic acid. Finally, by coupling multiple equivalents of the cyclic precursor onto the linear backbone, a cyclic brush-shaped polymer was prepared. This provides a highly efficient approach to prepare novel polymer architectures containing multiple cyclic components. / acase@tulane.edu

Merrill’s 2007 5 Star instrument, hereafter called the M-5 Star, is based on Merrill’s well recognized First Principles of Instruction. However, the instrument has not been tested for reliability and validity. In a pilot study, Cropper’s version of his instrument (C-5 Star) showed some reliability and validity evidence, but the M-5 Star needed similar evidence. To address this gap in the literature, the purpose of this study is to assess the reliability and validity evidence for M-5 Star. Raters were drawn from a graduate course in online course evaluation and asked to rate a sample (N = 6) of exclusively online university classes using M-5 Star and three comparison instruments. The comparison instruments also purport to examine course quality but lack the emphasis on instructional strategies in M-5 Star. Interrater reliability evidence for the M-5 Star and the comparison instruments was moderate to substantial (M5-Star ICC = .56, p = .001); Texas IQ ICC = .43, p = .001; WebCT ICC = .75, p = .001: SREB ICC = .53, p = .001). However, interrater reliability was tentative because rater pair scores were averaged, biasing the scores toward agreement and inflating ICC. Low correlations between M-5 Star (the criterion) and the comparison measures indicate divergent validity support that M-5 Star is measuring a different core concept of quality in online classes. M-5 Star correlation with WebCT was r = .39, p = .44 (r2 = .15), with WebCT was r = .44, p = .38 (r2 = .20), and with SREB was r = .43, p = .39 (r2 = .19). In addition to divergent validity analysis, a content validity index (CVI) analysis was undertaken using experts in the area of First Principles. According to First Principles experts, other than a few items on the rubric, the vast majority of the M-5 Star CVI results support close alignment with Merrill’s First Principles of Instruction. Of the 63 M-5 Star individual items, 56 (89%) of them received high scores on Aiken’s CVI that were significant at the .10 level. Study limitations are discussed at length, alongside calls for future research and practical and scholarly significance for the research.

This thesis is mainly concerned with the estimation of parameters of a first-order Smooth Threshold Autoregressive (STAR) model with delay parameter one. The estimation procedures include classical and Bayesian methods from a parametric and a semiparametric point of view.As the theoretical importance of stationarity is a primary concern in estimation of time series models, we begin the thesis with a thorough investigation of necessary or sufficient conditions for ergodicity of a first-order STAR process followed by the necessary and sufficient conditions for recurrence and classification for null-recurrence and transience.The estimation procedure is started by using Bayesian analysis which derives posterior distributions of parameters with a noninformative prior for the STAR models of order p. The predictive performance of the STAR models using the exact one-step-ahead predictions along with an approximation to multi-step-ahead predictive density are considered. The theoretical results are then illustrated by simulated data sets and the well- known Canadian lynx data set.The parameter estimation obtained by conditional least squares, maximum likelihood, M-estimator and estimating functions are reviewed together with their asymptotic properties and presented under the classical and parametric approaches. These estimators are then used as preliminary estimators for obtaining adaptive estimates in a semiparametric setting. The adaptive estimates for a first-order STAR model with delay parameter one exist only for the class of symmetric error densities. At the end, the numerical results are presented to compare the parametric and semiparametric estimates of this model.

Doctor of Philosophy / We investigate the linear growth and vertical structure of the magnetorotational instability (MRI) in weakly ionised, stratified accretion discs. The magnetic field is initially vertical and perturbations have vertical wavevectors only. Solutions are obtained at representative radial locations from the central protostar for different choices of the initial magnetic field strength, sources of ionisation, disc structure and configuration of the conductivity tensor. The MRI is active over a wide range of magnetic field strengths and fluid conditions in low conductivity discs. For the minimum-mass solar nebula model, incorporating cosmic ray and x-ray ionisation and assuming that charges are carried by ions and electrons only, perturbations grow at 1 AU for B < 8G. For a significant subset of these strengths (200mG < B < 5 G), the growth rate is of order the ideal MHD rate (0.75 Omega). Hall conductivity modifies the structure and growth rate of global unstable modes at 1 AU for all magnetic field strengths that support MRI. As a result, at this radius, modes obtained with a full conductivity tensor grow faster and are active over a more extended cross-section of the disc, than perturbations in the ambipolar diffusion limit. For relatively strong fields (e.g. B > 200 mG), ambipolar diffusion alters the envelope shapes of the unstable modes, which peak at an intermediate height, instead of being mostly flat as modes in the Hall limit are in this region of parameter space. Similarly, when cosmic rays are assumed to be excluded from the disc by the winds emitted by the magnetically active protostar, unstable modes grow at this radius for B < 2 G. For strong fields, perturbations exhibit a kink at the height where x-ray ionisation becomes active. Finally, for R = 5 AU (10 AU), unstable modes exist for B < 800 mG (B < 250 mG) and the maximum growth rate is close to the ideal-MHD rate for 20 mG < B < 500 mG (2 mG < B < 50 mG). Similarly, perturbations incorporating Hall conductivity have a higher wavenumber and grow faster than solutions in the ambipolar diffusion limit for B < 100 mG (B < 10 mG). Unstable modes grow even at the midplane for B > 100 mG (B ~ 1 mG), but for weaker fields, a small dead region exists. When a population of 0.1 um grains is assumed to be present, perturbations grow at 10 AU for B < 10 mG. We estimate that the figure for R = 1 AU would be of order 400 mG. We conclude that, despite the low magnetic coupling, the magnetic field is dynamically important for a large range of fluid conditions and field strengths in protostellar discs. An example of such magnetic activity is the generation of MRI unstable modes, which are supported at 1 AU for field strengths up to a few gauss. Hall diffusion largely determines the structure and growth rate of these perturbations for all studied radii. At radii of order 1 AU, in particular, it is crucial to incorporate the full conductivity tensor in the analysis of this instability, and more generally, in studies of the dynamics of astrophysical discs.

The WiggleZ Dark Energy survey is currently being carried out using the AAOmega instrument on the AAT. It is measuring redshifts for 240,000 emission line galaxies with high star-formation rates over 1,000 sq. degrees of sky. These galaxies are selected for spectroscopic observation from a combination of optical and ultraviolet imaging. The target selection criterion applied to these datasets is highly optimised to select high redshift emission line galaxies. The redshift distribution of these galaxies peaks at z

<p>Flygbranschen är en bransch som är mycket känslig för omvärldsfaktorer. De senaste årens konjunkturnedgång, terrorattentat, epidemier, höga oljepriser samt rådande konkurrenstryck har resulterat i stora lönsamhetsproblem för många flygbolag.</p><p>Ett sätt att bli mer konkurrenskraftig och förbättra sin position på marknaden är att samarbeta i form av en strategisk allians. Idag finns det tre allianser i flygbranschen: Star Alliance, Oneworld och Skyteam. Den första globala alliansen var Star Alliance som bildades 1997. Företag har under många år samarbetat i olika former. Vissa forskare anser att ett företag inte längre kan välja mellan konkurrens eller samarbete, utan att det handlar om att kombinera de båda strategierna. Denna undersökning avser att ta reda på hur en strategisk flygallians påverkar ett flygbolag.</p><p>För att avgränsa studien valdes SAS och dess samarbete inom Star Alliance som undersökningsobjekt. Studiens syfte är således att genom en fallstudie undersöka hur ett nätverksbolag har påverkats av att ingå i en strategisk flygallians. Två intervjuer har genomförts, en med en person anställd på SAS med tidigare förflutet i Star Alliance och en med en konsult med mångårig erfarenhet av resebranschen.</p><p>Resultatet visar att alliansamarbetet inneburit en rad fördelar för SAS. Konkurrensen har mildrats, kostnader reducerats, intäkter och utvecklingsmöjligheter ökat. En av nackdelarna med att ingå i en strategisk allians är att beslutsprocesserna förlängs. Något som SAS dock inte upplever som ett problem då medlemskapet i alliansen varit av stor betydelse för dem.</p><p>De slutsatser vi har dragit av denna undersökning är att de nämnda fördelarna med allianssamarbete kan ha ett högt pris då det kostar att vara medlem. Vi tror dock att det kan vara värt att betala en summa då samarbetet kan vara av betydelse för flygbolagets överlevnad. Då flygbolagen även samarbetar med flygbolag utanför alliansen ifrågasätter vi strategisk allians som den enda samarbetsformen för att uppnå minskad konkurrens, kostnadsreduceringar, ökade intäkter och utvecklingsmöjligheter.</p>

Industry clusters can be important components of regional development. The effects of industry clusters on growth typically vary across geography, which has implications for targeted development strategies. Employment and business establishment growth in the Appalachian region (2000 – 2008) was regressed on industry cluster concentration indexes controlling for local determinants. The hypothesis that local response to growth determinants is geographically heterogeneous was tested using Smooth Transition spatial process models. This class of models exhibiting regime switching behavior is useful for identifying regional clusters, providing another tool for exploring relationships between geographical determinants and economic growth.