O núcleo desta dissertação é desenvolver um conceito de path dependence mais parcimonioso, coerente e útil, seja teoricamente ou em estudos empíricos. Neste sentido, o insight fundamental é que se partimos de uma conceitualização mais dinâmica, baseada mais em externalidades negativas do que em rendimentos crescentes, o conceito de path dependence pode ser inerentemente mais operacionalizável, robusto e ressoar melhor com a literatura e os estudos Institucionalistas Históricos. O conceito de path dependence pode também ser mais compatível com várias elaborações realizadas dentro do próprio Institucionalismo Histórico sobre questões como mudança institucional, mecanismos explicativos, complementaridade, idéias e agência, e, portanto, enriquecer-se graças aos mesmos. / The objective of this dissertation is to develop a more parsimonious, coherent and useful concept of path dependence, both theoretically and empirically. Its fundamental insight is that with a more dynamic conceptualization, based more in negative externalities than in increasing returns, the concept of path dependence can be inherently more robust and resonate better with the literature and Historical Institutionalist studies. The concept of path dependence can also be more compatible with several theoretical developments which have arisen within Historical Institutionalism regarding questions such as institutional change, social mechanisms, complementarities, ideas, agency and, therefore, to be enriched by them.

It was hypothesized that field dependence and attention measures would differentiate accident-loaded and accident-free employees of a petroleum services company. Analysis of variance revealed main effects and a three-way interaction for the Rod-and-Frame Test. Main effects occurred for the Attention-Diagnostic Method and Embedded- Figures Test. No differences occurred for the Closure Test. Regression analysis produced an R (76) = .41, p < .01, with the Attention-Diagnostic Method contributing more to prediction. Equality-symmetry violations occurred in the data. Cautious interpretation was advised because of the assumption violations. The accident-loaded subjects produced consistently greater performance variances, which suggested general performance characteristics in several respects. Future research should be longitudinal-predictive, oriented from Kerr 's complementary safety theories.

The expected technical lifetime for a wind turbine is 20-25 years (Wizelius, 2007). In the process of planning a wind farm on a site an estimation of the average wind speed and the energy yield is required from the site. Due to large fluctuations in wind velocity from one year to another it is, from a climatologically point of view, not sufficient to measure the wind for a short period of time, e.g. one year. The year measured may have uncommonly high or uncommonly low winds and thereby generate an average not representative of the wind climate on the site. In the same time it is neither practical nor economically desirable to measure for a longer time period. Instead the measured data collected for a short period of time is scaled into a normal year before it is used to calculate the energy content. This normal year correction can be preformed using different methods. Principally, the methods relate the short time series, measured on the site, to one or more variables of a long time reference series. As a long time reference series the geostrophic wind on the site or a series of measured wind nearby can be used. If the correlation between the two series is sufficiently high a normal year correction may be done using the relation. Normal year correction has foremost been done using the relation between the velocities of the measured wind and a reference wind. The purpose in this study is to evaluate and implement a part of an algorithm for normal year correction considering additional variables besides wind velocity. The relationships studied are between measured wind speed and geostrophic wind speed, geostrophic wind direction and time of the year. For the purpose of evaluating the algorithm two wind data series from Näsudden, on the Swedish island of Gotland, for a period of 15 years has been used. Measured wind on 75 meters and geostrophic wind on 850hPa. Where the geostrophic wind has been used as a long time reference and the measured wind for one year at the time has been related to this reference. The relation has then been used together with the geostrophic wind data to create an estimation of the wind climate on Näsudden in three steps. Step one establishes the estimation due to the relation of geostrophic wind speed. Step two corrects the estimation due to the relation of geostrophic wind direction and step three corrects the estimation due to the relation of time of year. The conclusions from this study showed that with the method used for implementing the algorithm the normal year correction using only the relation between the velocities of the measured wind and the geostrophic wind gives the best estimation of the climatically mean wind speed. The standard deviation gives a 5 % risk for more than 0.436 m/s error for estimation of the mean wind on the site, which is comparable to earlier studies. The introduction of the wind direction dependence overestimates the mean wind on the site and amplifies the error. The introduction of the season dependence amplifies the error further and overestimates the mean wind additionally. / En vindturbin har en planerad livslängd på 20-25 år (Wizelius, 2007). Vid planering av en vindkraftspark behöver en estimering av medelvinden och energiutvinningen utföras för platsen man är intresserad av. På grund av stora fluktuationer av vindhastighet från år till år är det ur klimatologisk synpunkt inte tillräckligt att mäta under en kort period, exempelvis ett år. Det år man mäter kan ha ovanligt starka eller ovanligt svaga vindar och ge en icke representativ bild av vindklimatet på platsen. Samtidigt är det inte praktiskt eller ekonomiskt önskvärt att mäta under en längre tidsperiod. Istället kan den korta mätserie som insamlats korrigeras till ett normalår med hjälp av en långtidsreferens innan den används för att beräkna energiinnehållet. I princip går normalårskorrigering ut på att relatera den korta mätserien till en eller flera variabler i långtidsreferensen. Som långtidsreferensdata kan den geostrofiska vinden på platsen eller en lång mätserie från en närliggande plats användas. Om korrelationen mellan de två serierna är tillräckligt hög kan en normalårskorrigering göras med hjälp av relationen. Tidigare har man vid normalårskorrigering främst sett till relationen mellan vindhastigheterna för den uppmätta vinden och en referensvind. Syftet i detta arbete är att utvärdera en del av en algoritm för normalårskorrigering där hänsyn tas till fler variabler än endast vindhastighet. Samband som studeras är mellan uppmätt vindhastighet och geostrofisk vindhastighet, geostrofisk vindriktning och tid på året. För utvärderingen av algoritmen har två vinddataserier från Näsudden på Gotland använts för en period av 15 år med uppmätt vind på 75m och geostrofisk vind på 850hPa. Där den geostrofiska vinden fått representera långtidsreferensen och den uppmätta vinden för ett år i taget har relaterats till denna. Efter normalårskorrigeringen har den uppmätta vinden för 15 år fått representera vindklimatet på platsen som jämförelse. Enligt algoritmen har uppskattning av vindklimatet på Näsudden skapats i tre steg. Steg 1 är en uppskattning av vinden från sambandet för geostrofisk vindhastighet. Steg 2 är en korrektion av uppskattningen genom sambandet till geostrofisk vindriktning och steg 3 en korrektion av uppskattningen genom sambandet till tid på året. Efter vart steg skickas det aktuella estimatet vidare till nästa steg där det korrigeras med avseende på nästa samband. Slutsatserna från undersökningen visade att med den metod som använts ger normalårskorrigeringen med enbart sambandet till hastighet bäst uppskattning av den klimatologiska medelvinden. Standardavvikelsen för estimatet ger 5 % risk för mer än 0,436 m/s fel vid uppskattning av klimatologisk medelvind vilket är jämförbart med tidigare studier. Vidare överskattar införandet av vindriktningsberoendet den uppskattade medelvindhastigheten samt ökar osäkerheten. Även införandet av säsongsberoendet överskattar medelvindhastigheten ytterligare samt även osäkerheten.

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This dissertation summarizes three research projects related to microwave radiation induced electron transport properties in the GaAs/AlGaAs two dimensional electron systems. In chronological order, the projects are: a microwave reflection and electron magneto-transport correlation study, the combined microwave power and polarization dependence on microwave radiation induced magneto-resistance oscillations study, and a comparative study about the effect of circularly polarized and linearly polarized microwaves radiation on magneto-resistance oscillations induced due to the microwave. These three research projects experimentally address many interesting issues in the non-equilibrium low dimensional electron transport under microwave irradiation and provide potential applications of utilizing microwave radiation induced magneto-resistance oscillations in two dimensional electron systems as a method to detect different qualities of microwaves or terahertz waves.

IN ENGLISH Drug dependency in inflammatory bowel disease (IBD), Crohn's disease (CD) and ulcerative colitis (UC), is a specific disease phenotype which determines disease prognosis and hence may be used as a prognostic marker for treatment management. Drug dependency in IBD has been well described in corticosteroid treatment and recently also in infliximab (IFX) therapy. The aims of this thesis were: 1) to assess the occurrence of IFX dependency in paediatric and adult patients with CD; further to search for clinical and genetic predictors of IFX outcome and to evaluate the impact of IFX dependency on surgical rate; 2) to assess in CD patients the outcome of the first course of 5-ASA monotherapy with emphasis on 5-ASA dependency and to define clinical predictors of 5-ASA treatment outcome. We found that 66% of children and 29% of adults with CD became IFX dependent. The high frequency in paediatrics is in agreement with previously published studies, while the finding in adult patients indicates a lower rate of IFX dependency in the only study to date. Perianal disease and no bowel surgery prior to IFX start were predicative of IFX dependency in paediatric patients. In adult cohort, 2 genetic variants LTA c.207 A>G and CASP9 c.93 C>T were associated with IFX outcome, whereas no relevant clinical...

IN ENGLISH Drug dependency in inflammatory bowel disease (IBD), Crohn's disease (CD) and ulcerative colitis (UC), is a specific disease phenotype which determines disease prognosis and hence may be used as a prognostic marker for treatment management. Drug dependency in IBD has been well described in corticosteroid treatment and recently also in infliximab (IFX) therapy. The aims of this thesis were: 1) to assess the occurrence of IFX dependency in paediatric and adult patients with CD; further to search for clinical and genetic predictors of IFX outcome and to evaluate the impact of IFX dependency on surgical rate; 2) to assess in CD patients the outcome of the first course of 5-ASA monotherapy with emphasis on 5-ASA dependency and to define clinical predictors of 5-ASA treatment outcome. We found that 66% of children and 29% of adults with CD became IFX dependent. The high frequency in paediatrics is in agreement with previously published studies, while the finding in adult patients indicates a lower rate of IFX dependency in the only study to date. Perianal disease and no bowel surgery prior to IFX start were predicative of IFX dependency in paediatric patients. In adult cohort, 2 genetic variants LTA c.207 A>G and CASP9 c.93 C>T were associated with IFX outcome, whereas no relevant clinical...

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Title: Modelling dependence between hydrological and meteorological variables measured on several stations Author: Bc. Marie Turčičová Department: Department of Probability and Mathematical Statistics Supervisor: Prof. RNDr. Daniela Jarušková CSc., Czech Technical University in Prague, Faculty of Civil Engineering, Department of Mathematics Abstract: The aim of the thesis is to explore the dependence of daily discharge averages of the Opava river on high daily precipitation values in its basin. Three methods are presented that can be used for analyzing the dependence between high values of random variables. Their application on the studied data is also given. First it is the tail-dependence coefficient that measures the dependence between high values of two continuous random variables. The model for the high quantiles of the discharge at a given precipitation value was first determined non-parametrically by quantile regression and then parametrically through the peaks-over-threshold (POT) method. Keywords: extremal dependence, tail-dependence coefficient, quantile regression, peaks over threshold method

Estudos mostraram que o tráfego nas redes de dados tanto locais quanto de grande área, possui propriedades fractais como dependência de longa duração - Long-Range Dependence (LRD) e auto-similaridade. Devido à heterogeneidade de aplicações nessas redes, os traces de tráfego podem apresentar dependência de longa duração - Long Range Dependence (LRD), dependência de curta duração - Short Range Dependence (SRD) ou uma mistura de LRD com SRD. Sendo assim, este trabalho tem como objetivo sintetizar séries temporais gaussianas com flexibilidade de processamento no plano tempo-frequência a serem inseridas num gerador de tráfego com as características estatísticas específicas do tráfego encontrado em redes por comutação de pacotes reais, como autossimilaridade, LRD e SRD. Para isto foram desenvolvidos dois métodos para síntese de séries temporais gaussianas com LRD e simultânea introdução de SRD em diferentes faixas de frequência: Discrete Wavelet Tansform (DWT) com mapa de variâncias e Discrete Wavelet Packet Tansform (DWPT). Estes métodos utilizaram o mapa de variâncias cujo conceito foi desenvolvido neste trabalho. A validação dos métodos foi feita através de análise estatística e comparação com resultados de séries geradas pelo método Discrete Wavelet Transfom (DWT) de Backar utilizado em [1]. Além disso, também foi validada a ideia de que a DWPT é mais interessante que a DWT por ser mais flexível e prover uma maior flexibilidade de processamento no plano tempo-frequência. / Studies demonstrated that the data network traffic of Local Area Network (LAN) and Wide Area Network has fractal properties as long range dependence (LRD) and self-similarity. The traffic traces can show long range dependence, short range dependence or the both behaviors because of applications heterogeneity in these networks. This work objective is to synthetisize gaussian time series with processor flexibility in the time-frequency plan to be inserted in a traffic generator with the specific statistical traffic characteristics of real packet networks such as selfsimilarity, long range dependence (LRD) and short range dependence (SRD). Two methods were developed for the gaussian time series with LRD and SRD synthesis: Discrete Wavelet Tansform (DWT) with variance map and Discrete Wavelet Packet Tansform (DWPT). These methods used the variance map which concept was developed in this work. The methods validation was done by statistic analysis and comparison with the time series generated by the B¨ackar Discrete Wavelet Transfom (DWT) used by [1]. Besides of this, the idea that the DWPT is more because of its processing flexibility in the time-frequency plan was validated.