Error characteristics associated with satellite-derived precipitation products are important for atmospheric and hydrological model data assimilation, forecasting, and climate diagnostic applications. This information also aids in the refinement of physical assumptions within algorithms by identifying geographical regions and seasons where existing algorithm physics may be incorrect or incomplete. Examination of relative errors between independent estimates derived from satellite microwave data is particularly important over regions with limited surface-based equipments for measuring rain rate such as the global oceans and tropical continents. In this context, analysis of microwave based satellite datasets from the Tropical Rainfall Measuring Mission (TRMM) enables to not only provide information regarding the inherent uncertainty within the current TRMM products, but also serves as an opportunity to prototype error characterization methodologies for the TRMM follow-on program, the Global Precipitation Measurement (GPM) . Most of the TRMM uncertainty evaluation studies focus on the accuracy of rainfall accumulated over time (e.g., season/year). Evaluation of instantaneous rainfall intensities from TRMM orbital data products is relatively rare. These instantaneous products are known to potentially cause large uncertainties during real time flood forecasting studies at the watershed scale. This is more so over land regions, where the highly varying land surface emissivity offers a myriad of complications, hindering accurate rainfall estimation. The error components of orbital data products also tend to interact nonlinearly with hydrologic modeling uncertainty. Keeping these in mind, the present thesis fosters the development of uncertainty analysis using instantaneous satellite orbital data products (latest version 7 of 1B11, 2A25, 2A23, 2B31, 2A12) derived from the passive and active microwave sensors onboard TRMM satellite, namely TRMM Microwave Imager (TMI) and precipitation radar (PR). The study utilizes 11 years of orbital data from 2002 to 2012 over the Indian subcontinent and examines the influence of various error sources on the convective and stratiform precipitation types. Two approaches are taken up to examine uncertainty. While the first approach analyses independent contribution of error from these orbital data products, the second approach examines their combined effect. Based on the first approach, analysis conducted over the land regions of Mahanadi basin, India investigates three sources of uncertainty in detail. These include 1) errors due to improper delineation of rainfall signature within microwave footprint (rain/no rain classification), 2) uncertainty offered by the transfer function linking rainfall with TMI low frequency channels and 3) sampling errors owing to the narrow swath and infrequent visits of TRMM sensors. The second approach is hinged on evaluating the performance of rainfall estimates from each of these orbital data products by accumulating them within a spatial domain and using error decomposition methodologies. Microwave radiometers have taken unprecedented satellite images of earth’s weather, proving to be a valuable tool for quantitative estimation of precipitation from space. However, as mentioned earlier, with the widespread acceptance of microwave based precipitation products, it has also been recognized that they contain large uncertainties. One such source of uncertainty is contributed by improper detection of rainfall signature within radiometer footprints. To date, the most-advanced passive microwave retrieval algorithms make use of databases constructed by cloud or numerical weather model simulations that associate calculated microwave brightness temperature to physically plausible sample rain events. Delineation of rainfall signature from microwave footprints, also known as rain/norain classification (RNC) is an essential step without which the succeeding retrieval technique (using the database) gets corrupted easily. Although tremendous advances have been made to catapult RNC algorithms from simple empirical relations formulated for computational expedience to elaborate computer intensive schemes which effectively discriminate rainfall, a number of challenges remain to be addressed. Most of the algorithms that are globally developed for land, ocean and coastal regions may not perform well for regional catchments of small areal extent. Motivated by this fact, the present work develops a regional rainfall detection algorithm based on scattering index methodology for the land regions of study area. Performance evaluation of this algorithm, developed using low frequency channels (of 19 GHz, 22 GHz), are statistically tested for individual case study events during 2011 and 2012 Indian summer monsoonal months. Contingency table statistics and performance diagram show superior performance of the algorithm for land regions of the study region with accurate rain detection observed in 95% of the case studies. However, an important limitation of this approach is comparatively poor detection of low intensity stratiform rainfall. The second source of uncertainty which is addressed by the present thesis, involves prediction of overland rainfall using TMI low frequency channels. Land, being a radiometrically warm and highly variable background, offers a myriad of complications for overland rain retrieval using microwave radiometer (like TMI). Hence, land rainfall algorithms of TRMM TMI have traditionally incorporated empirical relations of microwave brightness temperature (Tb) with rain rate, rather than relying on physically based radiative transfer modeling of rainfall (as implemented in TMI ocean algorithm). In the present study, sensitivity analysis is conducted using spearman rank correlation coefficient as the indicator, to estimate the best combination of TMI low frequency channels that are highly sensitive to near surface rainfall rate (NSR) from PR. Results indicate that, the TMI channel combinations not only contain information about rainfall wherein liquid water drops are the dominant hydrometeors, but also aids in surface noise reduction over a predominantly vegetative land surface background. Further, the variations of rainfall signature in these channel combinations were seldom assessed properly due to their inherent uncertainties and highly non linear relationship with rainfall. Copula theory is a powerful tool to characterize dependency between complex hydrological variables as well as aid in uncertainty modeling by ensemble generation. Hence, this work proposes a regional model using Archimedean copulas, to study dependency of TMI channel combinations with respect to precipitation, over the land regions of Mahanadi basin, India, using version 7 orbital data from TMI and PR. Studies conducted for different rainfall regimes over the study area show suitability of Clayton and Gumbel copula for modeling convective and stratiform rainfall types for majority of the intraseasonal months. Further, large ensembles of TMI Tb (from the highly sensitive TMI channel combination) were generated conditional on various quantiles (25th, 50th, 75th, 95th) of both convective and stratiform rainfall types. Comparatively greater ambiguity was observed in modeling extreme values of convective rain type. Finally, the efficiency of the proposed model was tested by comparing the results with traditionally employed linear and quadratic models. Results reveal superior performance of the proposed copula based technique. Another persistent source of uncertainty inherent in low earth orbiting satellites like TRMM arise due to sampling errors of non negligible proportions owing to the narrow swath of satellite sensors coupled with a lack of continuous coverage due to infrequent satellite visits. This study investigates sampling uncertainty of seasonal rainfall estimates from PR, based on 11 years of PR 2A25 data product over the Indian subcontinent. A statistical bootstrap technique is employed to estimate the relative sampling errors using the PR data themselves. Results verify power law scaling characteristics of relative sampling errors with respect to space time scale of measurement. Sampling uncertainty estimates for mean seasonal rainfall was found to exhibit seasonal variations. To give a practical demonstration of the implications of bootstrap technique, PR relative sampling errors over the sub tropical river basin of Mahanadi, India were examined. Results revealed that bootstrap technique incurred relative sampling errors of <30% (for 20 grid), <35% (for 10 grid), <40% (for 0.50 grid) and <50% (for 0.250 grid). With respect to rainfall type, overall sampling uncertainty was found to be dominated by sampling uncertainty due to stratiform rainfall over the basin. In order to study the effect of sampling type on relative sampling uncertainty, the study compares the resulting error estimates with those obtained from latin hypercube sampling. Based on this study, it may be concluded that bootstrap approach can be successfully used for ascertaining relative sampling errors offered by TRMM-like satellites over gauged or ungauged basins lacking in in-situ validation data. One of the important goals of TRMM Ground Validation Program has been to estimate the random and systematic uncertainty associated with TRMM rainfall estimates. Disentangling uncertainty in seasonal rainfall offered by independent observations of TMI and PR enables to identify errors and inconsistencies in the measurements by these instruments. Motivated by this thought, the present work examines the spatial error structure of daily precipitation derived from the version 7 TRMM instantaneous orbital data products through comparison with the APHRODITE data over a subtropical region namely Mahanadi river basin of the Indian subcontinent for the seasonal rainfall of 6 years from June 2002 to September 2007. The instantaneous products examined include TMI and PR data products of 2A12, 2A25 and 2B31 (combined data from PR and TMI). The spatial distribution of uncertainty from these data products was quantified based on the performance metrics derived from the contingency table. For the seasonal daily precipitation over 10x10 grids, the data product of 2A12 showed greater skill in detecting and quantifying the volume of rainfall when compared with 2A25 and 2B31 data products. Error characterization using various error models revealed that random errors from multiplicative error models were homoscedastic and that they better represented rainfall estimates from 2A12 algorithm. Error decomposition technique, performed to disentangle systematic and random errors, testified that the multiplicative error model representing rainfall from 2A12 algorithm, successfully estimated a greater percentage of systematic error than 2A25 or 2B31 algorithms. Results indicate that even though the radiometer derived 2A12 is known to suffer from many sources of uncertainties, spatial and temporal analysis over the case study region testifies that the 2A12 rainfall estimates are in a very good agreement with the reference estimates for the data period considered. These findings clearly document that proper characterization of error structure offered by TMI and PR has wider implications in decision making, prior to incorporating the resulting orbital products for basin scale hydrologic modeling. The current missions of GPM envision a constellation of microwave sensors that can provide instantaneous products with a relatively negligible sampling error at daily or higher time scales. This study due to its simplicity and physical approach offers the ideal basis for future improvements in uncertainty modeling in precipitation.

Increasing global mean temperature or global warming has the potential to affect the hydrologic cycle. In the 21st century, according to the UN Intergovernmental Panel on Climate Change (IPCC), alterations in the frequency and magnitude of high intensity rainfall events are very likely. Increasing trend of urbanization across the globe is also noticeable, simultaneously. These changes will have a great impact on water infrastructure as well as environment in urban areas. One of the impacts may be the increase in frequency and extent of flooding. India, in the recent years, has witnessed a number of urban floods that have resulted in huge economic losses, an instance being the flooding of Mumbai in July, 2005. To prevent catastrophic damages due to floods, it has become increasingly important to understand the likely changes in extreme rainfall in future, its effect on the urban drainage system, and the measures that can be taken to prevent or reduce the damage due to floods. Reliable estimation of future design rainfall intensity accounting for uncertainties due to climate change is an important research issue. In this context, rainfall intensity-duration-frequency (IDF) relationships are one of the most extensively used hydrologic tools in planning, design and operation of various drainage related infrastructures in urban areas. There is, thus, a need for a study that investigates the potential effects of climate change on IDF relationships. The main aim of the research reported in this thesis is to investigate the effect of climate change on Intensity-Duration-Frequency relationship in an urban area. The rainfall in Bangalore City is used as a case study to demonstrate the applications of the methodologies developed in the research Ahead of studying the future changes, it is essential to investigate the signature of changes in the observed hydrological and climatological data series. Initially, the yearly mean temperature records are studied to find out the signature of global warming. It is observed that the temperature of Bangalore City shows an evidence of warming trend at a statistical confidence level of 99.9 %, and that warming effect is visible in terms of increase of minimum temperature at a rate higher than that of maximum temperature. Interdependence studies between temperature and extreme rainfall reveal that up to a certain range, increase in temperature intensifies short term rainfall intensities at a rate more than the average rainfall. From these two findings, it is clear that short duration rainfall intensities may intensify in the future due to global warming and urban heat island effect. The possible urbanization signatures in the extreme rainfall in terms of intensification in the evening and weekends are also inferred, although inconclusively. The IDF relationships are developed with historical data and changes in the long term daily rainfall extreme characteristics are studied. Multidecedal oscillations in the daily rainfall extreme series are also examined. Further, non-parametric trend analyses of various indices of extreme rainfall are carried out to confirm that there is a trend of increase in extreme rainfall amount and frequency, and therefore it is essential to the study the effects of climate change on the IDF relationships of the Bangalore City. Estimation of future changes in rainfall at hydrological scale generally relies on simulations of future climate provided by Global Climate Models (GCMs). Due to spatial and temporal resolution mismatch, GCM results need to be downscaled to get the information at station scale and at time resolutions necessary in the context of urban flooding. The downscaling of extreme rainfall characteristics in an urban station scale pose the following challenges: (1) downscaling methodology should be efficient enough to simulate rainfall at the tail of rainfall distribution (e.g., annual maximum rainfall), (2) downscaling at hourly or up to a few minutes temporal resolution is required, and (3) various uncertainties such as GCM uncertainties, future scenario uncertainties and uncertainties due to various statistical methodologies need to be addressed. For overcoming the first challenge, a stochastic rainfall generator is developed for spatial downscaling of GCM precipitation flux information to station scale to get the daily annual maximum rainfall series (AMRS). Although Regional Climate Models (RCMs) are meant to simulate precipitation at regional scales, they fail to simulate extreme events accurately. Transfer function based methods and weather typing techniques are also generally inefficient in simulating the extreme events. Due to its stochastic nature, rainfall generator is better suited for extreme event generation. An algorithm for stochastic simulation of rainfall, which simulates both the mean and extreme rainfall satisfactorily, is developed in the thesis and used for future projection of rainfall by perturbing the parameters of the rainfall generator for the future time periods. In this study, instead of using the customary two states (rain/dry) Markov chain, a three state hybrid Markov chain is developed. The three states used in the Markov chain are: dry day, moderate rain day and heavy rain day. The model first decides whether a day is dry or rainy, like the traditional weather generator (WGEN) using two transition probabilities, probabilities of a rain day following a dry day (P01), and a rain day following a rain day (P11). Then, the state of a rain day is further classified as a moderate rain day or a heavy rain day. For this purpose, rainfall above 90th percentile value of the non-zero precipitation distribution is termed as a heavy rain day. The state of a day is assigned based on transition probabilities (probabilities of a rain day following a dry day (P01), and a rain day following a rain day (P11)) and a uniform random number. The rainfall amount is generated by Monte Carlo method for the moderate and heavy rain days separately. Two different gamma distributions are fitted for the moderate and heavy rain days. Segregating the rain days into two different classes improves the process of generation of extreme rainfall. For overcoming the second challenge, i.e. requirement of temporal scales, the daily scale IDF ordinates are disaggregated into hourly and sub-hourly durations. Disaggregating continuous rainfall time series at sub-hourly scale requires continuous rainfall data at a fine scale (15 minute), which is not available for most of the Indian rain gauge stations. Hence, scale invariance properties of extreme rainfall time series over various rainfall durations are investigated through scaling behavior of the non-central moments (NCMs) of generalized extreme value (GEV) distribution. The scale invariance properties of extreme rainfall time series are then used to disaggregate the distributional properties of daily rainfall to hourly and sub-hourly scale. Assuming the scaling relationships as stationary, future sub-hourly and hourly IDF relationships are developed. Uncertainties associated with the climate change impacts arise due to existence of several GCMs developed by different institutes across the globe, climate simulations available for different representative concentration pathway (RCP) scenarios, and the diverse statistical techniques available for downscaling. Downscaled output from a single GCM with a single emission scenario represents only a single trajectory of all possible future climate realizations and cannot be representative of the full extent of climate change. Therefore, a comprehensive assessment of future projections should use the collective information from an ensemble of GCM simulations. In this study, 26 different GCMs and 4 RCP scenarios are taken into account to come up with a range of IDF curves at different future time periods. Reliability ensemble averaging (REA) method is used for obtaining weighted average from the ensemble of projections. Scenario uncertainty is not addressed in this study. Two different downscaling techniques (viz., delta change and stochastic rainfall generator) are used to assess the uncertainty due to downscaling techniques. From the results, it can be concluded that the delta change method under-estimated the extreme rainfall compared to the rainfall generator approach. This study also confirms that the delta change method is not suitable for impact studies related to changes in extreme events, similar to some earlier studies. Thus, mean IDF relationships for three different future extreme events, similar to some earlier studies. Thus, mean IDF relationships for three different future periods and four RCP scenarios are simulated using rainfall generator, scaling GEV method, and REA method. The results suggest that the shorter duration rainfall will invigorate more due to climate change. The change is likely to be in the range of 20% to 80%, in the rainfall intensities across all durations. Finally, future projected rainfall intensities are used to investigate the possible impact of climate change in the existing drainage system of the Challaghatta valley in the Bangalore City by running the Storm Water Management Model (SWMM) for historical period, and the best and the worst case scenario for three future time period of 2021–2050, 2051–2080 and 2071–2100. The results indicate that the existing drainage is inadequate for current condition as well as for future scenarios. The number of nodes flooded will increase as the time period increases, and a huge change in runoff volume is projected. The modifications of the drainage system are suggested by providing storage pond for storing the excess high speed runoff in order to restrict the width of the drain The main research contribution of this thesis thus comes from an analysis of trends of extreme rainfall in an urban area followed by projecting changes in the IDF relationships under climate change scenarios and quantifying uncertainties in the projections.

Le clinicien se trouve parfois confronté à des sujets qui présentent une surdité supérieure à 90 dB HL au-delà de 1 kHz avec une audition résiduelle dans les fréquences graves. Pour réhabiliter les hautes fréquences, il existe aujourd’hui différentes technologies : amplification conventionnelle, compression fréquentielle, implant cochléaire et depuis une dizaine d’année la stimulation électro-acoustique EAS qui consiste à stimuler acoustiquement les sons graves et électriquement les sons aigus via un implant cochléaire. La première partie de cette thèse a consisté à identifier les facteurs qui influencent les capacités des patients sourds partiels à traiter l’information basse fréquence de la parole. Nous avons utilisé un test d’audiométrie vocale filtrée passe-bas. Nos résultats indiquent que les scores d’intelligibilité de la parole sont positivement corrélés avec la durée de la surdité. Ceci signifie qu’avec le temps, ces sujets malentendants apprennent à comprendre avec cette audition type filtre passe-bas, à tel point que certains ont des performances supra-normales pour l’utilisation des basses fréquences. Nos résultats montrent également une corrélation négative entre l’âge d’apparition de la surdité et les scores l’intelligibilité. Ce test pourra aider le clinicien à mieux cibler l’appareillage le plus adapté à chaque profil de patient. La seconde partie de cette thèse, consacrée à l’EAS, a consisté à évaluer par des simulations chez le normo-entendant, diverses stratégies de codage du son par l’implant EAS. Actuellement, la stratégie utilisée pour l’EAS est calquée sur celle de l’implant cochléaire et nos résultats suggèrent que cette stratégie peut être optimisée. / Clinicians may face patients who have a deafness superior to 90 dB HL above 1 kHz with good lowfrequency residual hearing. Today, several technologies are available to provide high frequencies: conventional amplification, frequency compression, cochlear implant since about 10 years Electric-Acoustic Stimulation EAS which consists in stimulating acoustically low frequencies while stimulating electrically high frequency sounds via a cochlear implant. The firt part of this dissertation consisted in identifying the factors which may influence abilities of partially deaf subjects to process low-frequency speech information. We used a low-pass filtered speech test. Our results show that speech intelligibility scores are positively correlated to the duration of deafness. This means that these hearing-impaired subjects learn to understand with this lowpass-like hearing, in such a way that some of them exhibit supranormal abilities for the processing of low-frequency sounds. Our results also show a negative correlation between the age at onset of deafness and speech intelligibility scores. This test may help the clinician to better evaluate which device would be best for every patient’s profile. The second part of this dissertation, about EAS, consisted in evaluating through simulations in normal hearing listeners, several coding strategies by the EAS implant. Now the strategy used for EAS duplicates the strategy used by cochlear implants and our results suggest that this strategy could be optimized.

La condensation :un outil conceptuel pour la théorie de l’art / Résumé.<p><p>Notre étude sur la condensation tente de montrer l’intérêt d’une voie peu explorée dans le débat sur la nature de l’art, à savoir l’économie sensible des représentations symboliques. Nous donnons tout d’abord consistance au concept de condensation en suivant les écrits de Freud. Freud, un des rares auteurs à avoir thématisé cette notion, fournit dans L’interprétation des rêves les linéaments principaux du concept. Dans l’analyse de cet ouvrage, notre effort se porte sur la distinction entre une approche plastique et une approche symbolique de la condensation, c’est-à-dire l’obtention d’une condensation par composition de différentes figures ou par répétition d’une même représentation. En relation marginale avec la condensation, la méthode d’analyse des rêves nous montre l’importance des thèmes de l’idiosyncrasie et de la totalisation, lesquelles se révéleront en affinité étroite avec celui de la condensation. Nous procédons ensuite à l’analyse du second ouvrage d’importance rapporté à la condensation chez Freud, Le mot d’esprit et sa relation à l’inconscient. L’accent est porté, d’une part, sur la relation entre condensation et économie, et, d’autre part, sur la distinction entre deux états ou attitudes d’esprit révélée par le Witz. <p>Sur base de la thématisation freudienne, nous poursuivons la construction du concept de condensation à partir de l’expérience esthétique ordinaire. Cela comprend, tout d’abord, la simple considération du fonctionnement collégial et simultané de nos différents sens. Nous procédons ensuite à l’analyse de deux modes de représentation, tous deux fondés sur un rapport sensible au réel :la photographie et le cinéma. Par ces analyses, nous tentons de mettre en lumière les caractères élémentaires de la représentation sensible. Avec la photographie nous abordons l’économie sensible de la représentation, c’est-à-dire les transformations quantitatives et qualitatives qui sont au fondement du concept de condensation. Avec l’analyse du cinéma comme mode de représentation, l’effort est porté sur l’explicitation de la tension paradoxale entre présence et représentation dans le droit fil des développements sur le jeu des dimensions sensibles et l’hétérogénéité impliqués dans la représentation photographique. Cette deuxième partie assoit la validité objective du concept de condensation.<p>Dans un troisième temps, nous étayons cette validité objective du concept en la rapportant aux différents intervenants impliqués dans la réalité artistique (principalement, œuvre, créateur, récepteur). Enfin nous confrontons le concept de condensation à deux aspects de la théorie de l’art :un versant spéculatif, l’antinomie du jugement de goût avec les questions de la subjectivité et de l’objectivité, mais aussi et surtout celle de la communicabilité ;un versant plastique, les œuvres atypiques de Marcel Duchamp. Préalablement à l’analyse de ces deux aspects, nous consacrons un chapitre important à une définition du signe tenant compte de la responsabilité du sujet dans la constitution sémiotique. C’est sous le paramètre de la liberté dans notre rapport au symbolique que se rejoignent les deux aspects de la théorie de l’art abordés. <p><p><p><p><p><p>Condensation: A Conceptual Tool for the Theory of Art / Summary.<p><p><p>\ / Doctorat en philosophie et lettres, Orientation philosophie / info:eu-repo/semantics/nonPublished

Le niveau d'exigence minimum pour tout système 3D (images stéréoscopiques) est de garantir le confort visuel des utilisateurs. Le confort visuel est un des trois axes perceptuels de la qualité d'expérience (QoE) 3D qui peut être directement lié aux paramètres techniques du système 3D. Par conséquent, le but de cette thèse est de caractériser objectivement l'impact de ces paramètres sur la perception humaine afin de contrôler la qualité stéréoscopique. La première partie de la thèse examine l'intérêt de prendre en compte l'attention visuelle des spectateurs dans la conception d'une mesure objective de qualité 3D. Premièrement, l'attention visuelle en 2D et 3D sont comparées en utilisant des stimuli simples. Les conclusions de cette première expérience sont validées en utilisant des scènes complexes avec des disparités croisées et décroisées. De plus, nous explorons l'impact de l'inconfort visuel causé par des disparités excessives sur l'attention visuelle. La seconde partie de la thèse est dédiée à la conception d'un modèle objectif de QoE pour des vidéos 3D, basé sur les seuils perceptuels humains et le niveau d'acceptabilité. De plus nous explorons la possibilité d'utiliser la modèle proposé comme une nouvelle échelle subjective. Pour la validation de ce modèle, des expériences subjectives sont conduites présentant aux sujets des images stéréoscopiques fixes et animées avec différents niveaux d'asymétrie. La performance est évaluée en comparant des prédictions objectives avec des notes subjectives pour différents niveaux d'asymétrie qui pourraient provoquer un inconfort visuel. / The minimum requirement for any 3D (stereoscopic images) system is to guarantee visual comfort of viewers. Visual comfort is one of the three primary perceptual attributes of 3D QoE, which can be linked directly with technical parameters of a 3D system. Therefore, the goal of this thesis is to characterize objectively the impact of these parameters on human perception for stereoscopic quality monitoring. The first part of the thesis investigates whether visual attention of the viewers should be considered when designing an objective 3D quality metrics. First, the visual attention in 2D and 3D is compared using simple test patterns. The conclusions of this first experiment are validated using complex stimuli with crossed and uncrossed disparities. In addition, we explore the impact of visual discomfort caused by excessive disparities on visual attention. The second part of the thesis is dedicated to the design of an objective model of 3D video QoE, which is based on human perceptual thresholds and acceptability level. Additionally we explore the possibility to use the proposed model as a new subjective scale. For the validation of proposed model, subjective experiments with fully controlled still and moving stereoscopic images with different types of view asymmetries are conducted. The performance is evaluated by comparing objective predictions with subjective scores for various levels of view discrepancies which might provoke visual discomfort.

Abstract The central goal of this study was to study how contrastive accent is realised phonetically in three regional varieties of Standard Spoken Finnish. Speakers from the Oulu, Turku and Tampere regions produced unaccented and contrastively accented versions of the target words. Fundamental frequencies and segment durations were measured in all the target words, and in the contrastively accented versions also the temporal distance of the F0 peak from word onset. In the unaccented words, F0 fluctuations were very small, indicating once more that in Finnish, too, mere word stress is not realised tonally. In the words with CV.CV(X) structure, the lengthening of segment durations due to stress was restricted to the initial syllable in Tampere, whereas in Oulu and Turku the lengthening extended to the second syllable. The width of the fall-rise F0 pattern realising contrastive accent was in all word structures widest in the Oulu variety, and the narrowest in the Tampere variety. In the Turku variety CV.CV(X) words, the F0 peak occurred further away from word onset than in any other words investigated. The differences in segment durations among the varieties were similar in the unaccented words and in the contrastively accented ones, with one exception: the duration of V1 in the unaccented CV.CV(X) words was the same across the varieties, but in the contrastively accented CV.CV(X) words the duration of V1 was shorter in the Turku variety than in the other varieties. The durational ratio of V1 and V2 in the Turku variety – as in the Oulu variety – was different from the durational ratio in the Tampere variety: in Turku and Oulu V2 had a longer duration than V1, whereas in Tampere V1 had a longer duration than V2. This confirms earlier observations that Turku and Oulu belong to regions in which the V2 of CV.CV(X) words is half-long (longer than V1), but Tampere does not. However, the present study shows that the relative half-long duration of the V2 of CV.CV(X) words is achieved differently in Turku and Oulu: in Turku through the short duration of V1, but in Oulu through the long duration of V2. / Tiivistelmä Tämän tutkimuksen keskeisin tavoite oli selvittää, miten kontrastiivinen aksentti toteutuu foneettisesti kolmelta eri suomen murrealueelta kotoisin olevien yleiskielisessä puheessa. Oulun, Turun ja Tampereen seuduilta kotoisin olevat koehenkilöt tuottivat tutkimuksen jokaisesta kohdesanasta sekä aksentoimattoman että kontrastiivisesti aksentoidun esiintymän. Tuotetuista kohdesanoista mitattiin perustaajuuksia, äännesegmenttien kestot sekä kontrastiivisesti aksentoituiduista sanoista F0:n huipun etäisyys sanan alusta. Aksentoimattomissa sanoissa F0:n muutokset olivat kaikissa tutkituissa suomen varieteeteissa erittäin vähäisiä, mikä taas kerran todisti, ettei suomessakaan pelkkä sanapaino toteudu tonaalisesti. Sanapainon toteutumisessa kestojen avulla oli varieteettien välisiä eroja CV.CV(X)-rakenteisissa sanoissa: Tampereen varieteetissa sanapainon toteutumisala rajoittui ensimmäiseen tavuun, mutta Turun ja Oulun varieteeteissa se ulottui myös toiseen tavuun. Kontrastiivista aksenttia toteuttavan F0:n nousu–lasku-kuvion laajuus oli kaiken rakenteisissa kohdesanoissa suurin Oulun varieteetissa, pienempi Turun varieteetissa ja kaikkein pienin Tampereen varieteetissa. Muutoin kontrastiivisen aksentin toteutumisessa F0:n avulla oli huomattavia varieteettien välisiä eroja vain CV.CV(X)-rakenteisissa sanoissa: Turun varieteetin CV.CV(X)-sanoissa F0:n huippukohta sijaitsi kauempana sanan alusta kuin kaikissa muissa tutkituissa sanoissa, eli kauempana kuin muun rakenteisissa Turun varieteetin sanoissa ja kaiken rakenteisissa Oulun ja Tampereen varieteettien sanoissa. Varieteettien väliset segmenttien kestoerot olivat samat aksentoimattomissa ja kontrastiivisesti aksentoiduissa sanoissa, lukuun ottamatta sitä, että CV.CV(X)-rakenteisten sanojen V1:n kestossa ei aksentoimattomissa sanoissa ollut varieteettien välisiä eroja, mutta kontrastiivisesti aksentoiduissa sanoissa kyseisen segmentin kesto oli lyhempi Turun varieteetissa kuin muissa varieteeteissa. Tällä tavoin Turun varieteetin kontrastiivisesti aksentoiduissa CV.CV(X)-sanoissa toteutui V1:n ja V2:n kestosuhde, joka – samoin kuin Oulun varieteetin vastaava kestosuhde – poikkeaa Tampereen varieteetin vastaavasta kestosuhteesta: Turussa ja Oulussa V2 on V1:tä pitempikestoinen, Tampereella päinvastoin V1:n kesto on V2:n kestoa suurempi. Tämä vahvistaa ne aiempien tutkimusten tulokset, että Turku ja Oulu ovat ns. puolipidennysmurteiden aluetta, mutta Tampere ei. Kuitenkin tämä tutkimus osoitti, että kontrastiivisesti aksentoitujen sanojen puolipidennys saadaan Turun varieteetissa aikaan pikemminkin lyhytkestoisen V1:n kuin pitkäkestoisen V2:n avulla, kun taas Oulun varieteetissa puolipidennys syntyy nimenomaan pitkäkestoisen V2:n avulla. Kaiken kaikkiaan suurin osa tutkimuksessa todetuista varieteettien välisistä selvistä perustaajuus- ja kestoeroista koski CV.CV(X)-rakenteisia sanoja, jotka ovatkin erikoinen suomen sanatyyppi yksimoraisen ensi tavunsa vuoksi.

Olivier Messiaen is regarded as one of the most significant composers of the 20th century. His compositions are performed regularly and his teachings have influenced many well-known composers like Boulez and Stockhausen. This study focussed on his use of rhythm in his piano compositions. I supplied a short biography of the composer along with a brief discussion of his compositional techniques. Thereafter his rhythmic techniques were examined through relevant music examples from his piano repertoire. Particular attention was given to works from the Vingt Regards sur L’Enfant-Jésus along with Cantéyodjayâ, Mode de valeurs et d’intensités and Neumes rythmiques from his experimental period (1949-1951). In Mode de valeurs et d’intensités he revolutionized the serial treatment of duration, pitch, intensity and attack. His other rhythmic techniques include Indian rhythms, Greek meter, added values, augmentation, diminution, non-retrogradable rhythms, polyrhythm, chromatic scales of duration, personnages rythmiques, symmetrical permutations, rhythmic neumes, rhythmic canon and prime numbers. / Dissertation (MMus (Performing Arts))--University of Pretoria, 2008. / Music / unrestricted

The work deals with the theoretical basis and the practical approach for determining the risk-free rate of return. The aim of the work is to form recommendations which should analysts follow in determining the risk-free rate of return in the Czech Republic. The first part focuses on theoretical basis of risk-free rate of return and market interest rates. Further, the criteria of risk-free investments are defined in this chapter. The second and third part focuses on determination of the risk-free rate of return using yield to maturity of government bond and yield curve which was derived with using the Nelson-Siegel model. The table of forward rates at the end of each month from January 1999 to April 2010 is attached.

Cette thèse s’intéresse d’une part aux effets macroéconomiques des régimes de change, et d’autre part, aux récentes évolutions sur la politique budgétaire et la décentralisation. La partie I met essentiellement l’accent sur l’interaction entre les régimes de change (RC) et la politique budgétaire, monétaire et fiscale. Tout d’abord, nous mettons en évidence que les RC peuvent avoir un effet stabilisateur sur la politique budgétaire (chapitre 1). Cependant, cet effet stabilisateur des RC n’est pas automatique mais dépendrait plutôt des conséquences d’une politique budgétaire laxiste. Le chapitre 2 s’intéresse quant à lui à la causalité entre RC et crises (bancaire/financière, de change et de dette) et remet en cause la vision bipolaire qui prétendait que les RC intermédiaires sont plus vulnérables aux crises que les solutions en coin (RC fixes/flexibles). Il ressort de notre analyse que les fondamentaux macroéconomiques (la volatilité du crédit au secteur privé, le financement du déficit, et le ratio dette sur PIB) jouent un rôle considérable. Le chapitre 3 met en évidence un lien entre les RC et la politique fiscale. Les pays à RC fixes montrent une plus grande dépendance aux recettes domestiques –telles que la TVA-, comparativement aux pays en change intermédiaires/flexibles pour compenser les pertes de recettes de seigneuriage (effet de substitution). De plus, ces pays avec RC fixes collectent plus de recettes domestiques en compensation de la perte de recettes douanières, suite à la libéralisation commerciale (effet de compétitivité). Dans les trois derniers chapitres (partie II), nous mettons le focus sur la politique budgétaire et les effets de la décentralisation. Le chapitre 4 révèle une relation non-linéaire entre la politique budgétaire et le cycle économique, qui dépend du niveau de la dette publique. Lorsque celle-ci dépasse un certain seuil (87%), la politique budgétaire perd toute propriété contra-cyclique. Nous montrons par ailleurs que l’effet disciplinaire ex-ante des règles budgétaires aide à restaurer la contra-cyclicité de la politique budgétaire. A travers le chapitre 5, nous montrons que la décentralisation budgétaire, dans un cadre politico-institutionnel sein et dépourvu de corruption, améliore l’offre de biens et services publics. Le chapitre 6 conclut que la décentralisation impacte positivement le solde structurel. Cependant une asymétrie entre la décentralisation des dépenses et celle des recettes accroit la dépendance des gouvernements locaux vis-à-vis du gouvernement central en termes de transferts, et amoindrirait considérablement à l’effet positif de la décentralisation. / This thesis explored, in two parts, the macroeconomic impacts of exchange rate regimes (ERR), as well as the recent developments in fiscal policy and fiscal decentralization. Part I has reconsidered the role of ERR and its interplay with fiscal, monetary and tax policy. The first result that emerges (Chapter 1) is that fixed ERR can serve as a credible policy tool for stabilizing fiscal policy. However, this stabilizing effect is conditional upon the inter-temporal distribution of the costs of loose fiscal policy. In assessing the linkage between ERR and crises (banking/financial, currency and debt), Chapter 2 evidenced that the bipolar view is no longer valid, and that, crisis proneness rather depends on the macroeconomic fundamentals (the volatility of private sector credit, the deficit-financing mechanism, and the debt-to-GDP ratio). In Chapter 3, we unveiled a strong relationship between ERR and tax policy. Countries with pegged regimes have greater reliance on domestic taxation -such as the VAT- to make up for the loss of seigniorage revenue (substitution effect). Moreover, peggers tend to collect more VAT revenue to offset the shortfall in cross border taxes following the trade liberalization reform (competitiveness effect). Part II discussed the cyclical response of fiscal policy in high debt periods, and focused on fiscal decentralization issues. In Chapter 4, we showed that the reaction of fiscal policy to the business cycle is non-linear and conditional to the level of public debt. When the debt-to-GDP ratio goes beyond a certain threshold (87%), fiscal policy loses its counter-cyclical properties. Further, we highlighted that carefully-designed fiscal rules help maintaining counter-cyclicality through an ex ante disciplinary effect. Chapters 5 and 6 analyzed the impact of fiscal decentralization on the efficiency of public service delivery and fiscal policy performance, respectively. Chapter 5 revealed that a sufficient level of expenditure decentralization, coupled with revenue decentralization, improves the efficiency of public service delivery. However, the political and institutional environment is critical for reaping decentralization-led benefits. Lastly, Chapter 6 concluded that fiscal decentralization has destabilizing effect by reducing the counter-cyclicality of fiscal policy. In addition, we found that decentralization strengthens the structural fiscal balance; however, vertical fiscal imbalances reduce the benefits of decentralization. It is therefore critical to limit asymmetries between expenditure and revenue decentralization, so as to reduce the transfer-dependency of local governments to the central level, and thus prevent decentralization from weakening the fiscal stance at the general government level.

No contexto de Smart Grids, determinar a correta localização das fontes causadoras de Variação de Tensão de Curta Duração (VTCD) não é uma tarefa simples, devido à curta duração destes eventos e também, por sua rápida propagação nas redes de distribuição de energia elétrica. Neste sentido, esse trabalho apresentou um método híbrido recursivo baseado em ferramentas da área de aprendizado de máquinas (algoritmo de agrupamento e base de regras), o qual é capaz de localizar as fontes de VTCD, a partir da análise dos das características dos distúrbios disponibilizadas pelos smart meters instalados no sistema. Assim, o trabalho destinouse ao desenvolvimento de uma plataforma em hardware para aquisição, detecção e classificação dos distúrbios, através de um Sistema Operacional de Tempo Real. Em seguida o algoritmo de agrupamento (k-means) agrupou os dados dos medidores de forma a definir dois clusters, onde um deles correspondeu aos medidores que estão longe da região que ocorreu o distúrbio e o outro, correspondeu aos medidores que estavam localizados próximos da região de ocorrência do distúrbio. Na segunda etapa, um sistema baseado em regras determinou qual dos clusters abrangeu o nó de origem. No entanto, quando o algoritmo determinou uma região muito grande, essa região é introduzida recursivamente, como entrada da metodologia desenvolvida, para refinar a região de localização. O sistema resultante foi capaz de estimar a região de localização com uma taxa de acerto acima de 90%. Assim, o método teve sua concepção adequada ao empregado nos centros de controle e operações de concessionárias de energia elétrica, visando apoiar a decisão do corpo técnico para que ações corretivas fossem estabelecidas de forma assertiva. / In the Smart Grids context, the correct location of short-duration voltage variations sources is not a trivial task, because of the short duration of these events and for rapid propagation in the distribution feeder. In this sense, aiming to develop a recursive hybrid method based on machine learning area tools (clustering algorithm and rule base) that is able to locate the sources of short-duration voltage variations, it was used data from smart meters installed along the distribution feeder. The recursive hybrid method, as input, received the disturbance characteristics provided by the meters installed in the system. Thus, this thesis aimed to development of a measurement hardware for signal acquisition, detection, classification through a realtime operating system. Then, k-means clustering algorithm grouped the meters data in order to define two clusters, where one of them corresponded to the meters that were distant from the region that occurred the disturbance and the other one corresponded to the meters, which were located near to the disturbance occurrence region. In a second step, a rule-based system determined which of the clusters corresponded to the source node. When the algorithm determined a very large region, that region was recursively introduced as input of the developed methodology to decrease its size. The resulting system was able to estimate the location region with a accuracy above 90%. Therefore, this method showed a suitable design for employment by operation control centers of power sector concessionaires, aiming to support technical staff decision to stablish assertive corrective actions.