This thesis provides a thorough analysis of the covered- and uncovered interest parity conditions (CIP, UIP) as well as the forward rate unbiasedness hypothesis (FRUH) for Sweden and the European Economic and Monetary Union (EMU). By studying data on interbank rates in Sweden (STIBOR) and the EMU (EURIBOR) as well as the corresponding spot- and forward exchange rates, monetary integration and country-specific risks are determined and analyzed with direct applications to the potential entry of Sweden into the EMU. As interest rate parity in general gives insight into market efficiency and frictions between the chosen regions, such points are discussed in addition to EMU entry. Drawing on past studies that mainly studied one condition in isolation, a nested formulation of interest rate parity is instead derived and tested using cointegration and robust estimation methods. The results point to a strict rejection of the FRUH for all horizons except the shortest and a case where CIP only holds for the 6-month horizon and partially over one year. This implies, based on the nested formulation, that UIP is rejected for all horizons as well. Ultimately, the study concludes that a Swedish entry into the EMU is not motivated given the lackluster results on UIP and due to the lack of monetary integration. / Den här uppsatsen presenterar en djupgående analys av det kurssäkrade- och icke-kurssäkrade ränteparitetsvillkoret samt den effektiva marknadshypotesen på valutaterminer för Sverige och den europeiska ekonomiska och monetära unionen (EMU). Genom att studera data på interbankräntor i Sverige (STIBOR) och EMU (EURIBOR) samt respektive spot- och valutaterminskurser så skattas och analyseras monetär integration samt landsspecifika risker med en direkt tillämpning på Sveriges eventuella inträde i EMU. Eftersom ränteparitet generellt ger insikt i marknadseffektivitet och friktioner regioner emellan, diskuteras även dessa punkter utöver ett eventuellt EMU-inträde. Genom att bygga på föregående studier som i huvudsak studerar ränteparitetsvillkoren var för sig, härleds en sekventiell formulering av villkoren som sedan testas med kointegration och robusta estimeringsmetoder. Resultaten ger att den effektiva marknadshypotesen strikt förkastas på alla tidshorisonter förutom på en dag respektive en vecka, samt att kurssäkrad ränteparitet håller på 6 och delvis 12 månaders sikt. Baserat på den sekventiella formuleringen så innebär detta att icke-kurssäkrad ränteparitet inte håller på någon tidshorisont. Slutligen, baserat på både resultat och diskussion, är ett svenskt inträde i EMU inte motiverbart givet negativa resultat för icke-kurssäkrad ränteparitet och avsaknaden av fullständig monetär integration mellan regionerna.

In the recent years, the exponential Internet traffic growth projections place enormous transmission rate demand on the underlying information infrastructure at every level, from the long haul submarine transmission to optical metro networks. In recent years, optical transmission at 100 Gb/s Ethernet date rate has been standardized by ITU-T and IEEE forums and 400Gb/s and 1Tb/s rates per DWDM channel systems has been under intensive investigation which are expected to be standardized within next couple of years.To facilitate the implementation of 400GbE and 1TbE technologies, the new advanced modulation scheme combined with advanced forward error correction code should be proposed. Instead of using traditional QAM, we prefer to use some other modulation techniques, which are more suitable for current coherent optical transmission systems and can also deal with the channel impairments. In this dissertation, we target at improving the channel capacity by designing the new modulation formats. For the first part of the dissertation, we first describe the optimal signal constellation design algorithm (OSCD), which is designed by placing constellation points onto a two dimensional space. Then, we expand the OSCD onto multidimensional space and design its corresponding mapping rule. At last, we also develop the OSCD algorithm for different channel scenario in order to make the constellation more tolerant to different channel impairments. We propose the LLR-OSCD for linear phase noise dominated channel and NL-OSCD for nonlinear phase noise dominated channel including both self-phase modulation (SPM) and cross-phase modulation (XPM) cases. For the second part of the dissertation, we target at probability shaping of the constellation sets (non-uniform signaling). In the conventional data transmission schemes, the probability of each point in a given constellation is transmitted equally likely and the number of constellation sets is set to 2!. If the points with low energy are transmitted with larger probability then the others with large energy, the non- uniform scheme can achieve higher energy efficiency. Meanwhile, this scheme may be more suitable for optical communication because the transmitted points with large probabilities, which have small energy, suffer less nonlinearity. Both the Monte Carlo simulations and experiment demonstration of both OSCD and non-uniform signaling schemes indicate that our proposed signal constellation significantly outperforms QAM, IPQ, and sphere-packing based signal constellations.

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: Low earth orbit (LEO) satellite communication presents a unique environment which inherently di ers from most other communication channels. Due to the varying orbital patterns of LEO satellites the link exhibits varying link margins. Limited communication time windows need to be optimised to maximise the volumetric data throughput. Large coding gains can be obtained by the implementation of forward error correction codes. This thesis presents a means for optimising the data throughput of LEO satellite communication through the implementation of a mission speci c error control strategy. Low density parity check (LDPC) codes are versatile and present good error performances at many di erent code rates and block lengths. With power limitations on the space segment and remote ground stations, hardware utilisation e ciency must be optimised to reduce power consumption. In response to this requirement, this thesis evaluates various algorithms for LDPC decoders. An iterative LDPC decoder, implementing an approximation algorithm, is presented as a low complexity solution with good error performance. The proposed solution provides a very good balance between required hardware complexity and coding performance. It was found that many parameters of the decoders and codes can be altered to allow the implementation of these codes in systems with varying memory and processing capabilities. / AFRIKAANSE OPSOMMING: Kommunikasiekanale van satelliete met lae wentelbane, bied 'n unieke omgewing wat inherent verskil van meeste ander kommunikasiekanale. As gevolg van veranderende wentelbaanpatrone, vertoon die kanaal 'n wisselende foutgedrag. Kommunikasievensters is beperk en moet geoptimeer word om die totale deurset van die stelsel te maksimeer. Groot koderingswinste kan verkry word deur die implementering van foutkorreksie kodes. Hierdie tesis voorsien 'n metode om die datadeurset van satelliete met lae wentelbaan te optimeer, deur middel van implementering van 'n missie-spesi eke foutbeheer strategie. Lae digtheid pariteit toetskodes (LDPC) is veelsydige kodes, bied goeie foutbeheer en is doeltre end vir verskillende kodekoerse en bloklengtes. Met drywingsbeperkinge op die ruimtesegment en afgesonderde grondstasies, moet hardeware komponente doeltreffend gebruik word om drywingsverbruik te verminder. Ten einde aan hierdie ontwerpsvereiste te voldoen, evalueer hierdie tesis verskeie LDPC dekodeerderalgoritmes. Deur 'n iteratiewe LDPC dekodeerder met 'n benaderingsalgoritme te implementeer, word 'n oplossing van lae kompleksiteit aangebied, maar wat steeds goeie foutkorreksie eienskappe toon. Die voorgestelde oplossing bied 'n baie goeie balans tussen benodigde hardeware kompleksiteit en koderingsprestasie. Daar is gevind dat heelwat parameters van die dekodeerders en kodes aangepas kan word, ten einde implementering in stelsels met 'n wye verskeidenheid van geheuespasie en verwerkingsvermoëns moontlik te maak.

Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: A collaboration between the Katholieke Universiteit van Leuven (KUL) and Stellenbosch University (SU), resulted in the development of a satellite based platform for use in agricultural sensing applications. This will primarily serve as a test platform for a digitally beam-steerable antenna array (SAA) that was developed by KUL. SU developed all flight - and ground station based hardware and software, enabling ground to flight communications and interfacing with the KUL SAA. Although most components had already been completed at the start of this M:Sc:Eng: project, final systems integration was still unfinished. Modules necessary for communication were also outstanding. This project implemented an automatic repeat and request (ARQ) strategy for reliable file transfer across the wireless link. Channel coding has also been implemented on a field programmable gate array (FPGA). This layer includes an advanced forward error correction (FEC) scheme i.e. a low-density parity-check (LDPC), which outperforms traditional FEC techniques. A flexible architecture for channel coding has been designed that allows speed and complexity trade-offs on the FPGA. All components have successfully been implemented, tested and integrated. Simulations of LDPC on the FPGA have been shown to provide excellent error correcting performance. The prototype has been completed and recently successfully demonstrated at KUL. Data has been reliably transferred between the satellite platform and a ground station, during this event. / AFRIKAANSE OPSOMMING: Tydens ’n samewerkingsooreenkoms tussen die Katholieke Universiteit van Leuven (KUL) en die Universiteit van Stellenbosch (US) is ’n satelliet stelsel ontwikkel vir sensor-netwerk toepassings in die landbou bedryf. Hierdie stelsel sal hoofsaaklik dien as ’n toetsmedium vir ’n digitaal stuurbare antenna (SAA) wat deur KUL ontwikkel is. Die US het alle hardeware en sagteware komponente ontwikkel om kommunikasie d.m.v die SAA tussen die satelliet en ’n grondstasie te bewerkstellig. Sedert die begin van hierdie M:Sc:Ing: projek was die meeste komponente alreeds ontwikkel en geïmplementeer, maar finale stelselsintegrasie moes nog voltooi word. Modules wat kommunikasie sou bewerkstellig was ook nog uistaande. Hierdie projek het ’n ARQ protokol geïmplementeer wat data betroubaar tussen die satelliet en ’n grondstasie kon oordra. Kanaalkodering is ook op ’n veld programmeerbare hekskikking (FPGA) geïmplementeer. ’n Gevorderde foutkorrigeringstelsel, naamlik ’n lae digtheids pariteit toetskode (LDPC), wat tradisionele foutkorrigeringstelsels se doeltreffendheid oortref, word op hierdie FPGA geïmplementeer. ’n Kanaalkoderingsargitektuur is ook ontwikkel om die verwerkingspoed van data en die hoeveelheid FPGA logika wat gebruik word, teenoor mekaar op te weeg. Alle komponente is suksesvol geïmplementeer, getoets en geïntegreer met die hele stelsel. Simulasies van LDPC op die FPGA het uistekende foutkorrigeringsresultate gelewer. ’n Werkende prototipe is onlangs voltooi en suksesvol gedemonstreer by KUL. Betroubare data oordrag tussen die satelliet en die grondstasie is tydens hierdie demonstrasie bevestig.

This thesis is devoted to the study of a compression and transmission framework for video. It exploits the JPEG 2000 standard and the coding with side information principles to enable an efficient interactive browsing of video sequences. During the last decade, we have witnessed an explosion of digital visual information as well as a significant diversification of visualization devices. In terms of viewing experience, many applications now enable users to interact with the content stored on a distant server. Pausing video sequences to observe details by zooming and panning or, at the opposite, browsing low resolutions of high quality HD videos are becoming common tasks. The video distribution framework envisioned in this thesis targets such devices and applications. Based on the conditional replenishment framework, the proposed system combines two complementary coding methods. The first one is JPEG 2000, a scalable and very efficient compression algorithm. The second method is based on the coding with side information paradigm. This technique is relatively novel in a video context, and has been adapted to the particular scalable image representation adopted in this work. Interestingly, it has been improved by integrating an image source model and by exploiting the temporal correlation inherent to the sequence. A particularity of this work is the emphasis on the system scalability as well as on the server complexity. The proposed browsing architecture can scale to handle large volumes of content and serve a possibly very large number of heterogeneous users. This is achieved by defining a scheduler that adapts its decisions to the channel conditions and to user requirements expressed in terms of computational capabilities and spatio-temporal interest. This scheduling is carried out in real-time at low computational cost and in a post-compression way, without re-encoding the sequences.

Östersjön har alltid varit en viktig knutpunkt för de länder som angränsar dit för att göra det möjligt att handla med varandra och på så sätt skapa en internationell marknad sinsemellan varandra. Under 1700-1800-talet tog produktionen fart och tack vare merkantilismen utvecklades den internationella handeln. För att fastställa deras växelkurs har många länder använt sig av olika myntfot såsom till exempel guldmyntfoten där valutans värde bestämdes utifrån värdet på motsvarande mängd guld vilket innebär att växelkurserna var fasta. Utifrån guldmyntfoten utvecklades teorierna lagen om ett pris och köpkraftsparitet med principerna om att en enhet valuta ska ha samma köpkraft även i andra länder vilket innebär att en vara ska kunna köpas för samma mängd av valutan oavsett om det är inrikes eller utrikes. Dessa teorier har studerats flertalet gånger, både för kort och lång sikt, med fåtalet länder till ett större antal. Denna studie använder sig av teoriernas grundidé och testar huruvida PPP i dess absoluta samt relativa form håller för Östersjöns handelsområde. För att kunna testa detta har två ekonometriska tester av de variabler som används gjorts, stationäritetstest och kointegrationstest. Stationäritetstestet visade att alla variabler förutom de tidsserier som användes för att testa relativ PPP led av icke-stationäritet och därmed behövdes differentieras för att kunna användas för att testa PPP. Kointegrationstestet visade att ingen av tidsserierna led av kointegration vilket medförde att vidare korrigeringsmodeller ej behövdes göras. Resultatet från de ekonometriska skattningarna visade på att absolut och relativ PPP ej kunde bekräftas, ej heller förnekas, då inga signifikanta koefficienter kunde konstateras. Vid testandet av real växelkurs för relativ PPP gavs signifikanta tidsserier men ej i enlighet med nollhypotesen och därmed förkastades nollhypotesen om att relativ PPP håller. Utifrån resultatet dras slutsatsen att PPP ej kan bekräftas utan att vidare studier måste göras. / The Baltic sea has always been an important transit hub for neighboring countries and the sea have made ​​it possible for the countries to trade with each other and thus create an international trade among themselves to each other. During 1700-1800's, the production took off and because of the mercantilism international trade developed. To establish their exchange rate, many countries have followed different standards, such as the gold standard where the currency's value was determined from the value of the corresponding quantity of gold which implies that the exchange rates were fixed. Based on the gold standard different theories was developed, such as the law of one price and purchasing power parity with the principles that a single currency will have the same purchasing power in other countries, which implies that a commodity should be bought for the same amount of currency, whether it is domestic or foreign. These theories have been studied several times, both for the short and long term, with the few countries to a greater number. In order to test this, two econometric tests of the variables were made​​, stationarity test and cointegration test. The stationarity test showed that all variables except the time series that was used to test relative PPP suffered from non-stationarity and therefore needed to be differentiated to be used to test the PPP. The cointegration test showed that no one of the time series suffered of cointegration and therefore further correction models was not needed to be done. The results from the econometric estimates showed that absolute and relative PPP could not be confirmed, nor denied, since no significant coefficients were identified. In the testing of real exchange rate for relative PPP significant time series were given but not in accordance with the nullhypothesis and therefore the null hypothesis is rejected that the relative PPP holds. From the results it is concluded that the PPP cannot be confirmed without that further studies must be done.

This thesis explores the constitutionality of compulsory electoral quotas for women imposed by law. The central question this thesis attempts to answer is what makes these quotas constitutional or unconstitutional in a given jurisdiction. A double methodology was employed to answer this question: theoretical and comparative. From a theoretical perspective, it is proposed that the constitutionality of electoral quotas for women depends on the approach that domestic legal orders adopt to four issues: political representation, equality, affirmative action and political rights. An additional crosscutting factor that influences the constitutionality of these quotas is gender, mainly through its effects on the understanding of political representation and equality. From the comparative law perspective, three jurisdictions were analysed: France, Spain and Mexico. After exploring these systems' approaches to political representation, equality, affirmative action and political rights, the process of adoption of electoral quotas for women is discussed, particularly the constitutional litigation about quota laws. Finally, the relationship between the theory and the practice of assessing the constitutionality of electoral quotas for women is analysed, concluding that although courts use a theoretical framework formed by political representation, equality, affirmative action and political rights, they adopt a somewhat simplistic approach to these issues, using only one of these theoretical factors as the primary determinant, often side-stepping the most controversial issues connected with these factors, and almost completly ignoring the particularities of the target group (women). Additionally, in each jurisdiction the decisions of the courts are also influenced by domestic political and legal factors.

Introdução: O crescimento do número de idosos no Brasil tem aumentado o interesse em identificar os determinantes da sua sobrevida e da incidência de doenças crônicas. A menopausa é definida como a cessação permanente da menstruação e está associada à diminuição da secreção de estrógenos por perda da função folicular, marcando o fim da fase reprodutiva na vida feminina. A idade da menopausa tem sido associada em alguns estudos internacionais com a mortalidade e algumas causas de morbidade, mas faltam estudos sobre o tema no Brasil. Esta tese será apresentada por meio de 3 artigos. O primeiro analisou os fatores associados à idade da menopausa natural em mulheres do estudo SABE (Saúde, Bem-estar e Envelhecimento). O tabagismo e a escolaridade estiveram estatisticamente associados com uma menopausa mais cedo nas três coortes analisadas: 2000, 2006 e 2010. Mulheres fumantes atuais tiveram 35% maior risco de ter menopausa precoce (HR=1.35, 95% CI: 1.12, 1.62) e as ex-fumantes 27% maior risco (HR=1.27, 95% CI: 1.09, 1.50), em comparação com as mulheres que nunca fumaram. Em relação à escolaridade, as mulheres com 8 anos ou mais de estudos tiveram 33% menor risco de menopausa precoce (HR=0.67, 95% CI: 0.50, 0.89) comparadas às mulheres sem escolaridade. Estado civil e número de filhos estiveram associados a uma menopausa mais tardia na coorte 2006. No segundo artigo, foi realizada uma análise de sobrevida segundo a idade da menopausa natural das mulheres pertencentes à coorte 2000. Foram identificados 444 óbitos de mulheres até 2016. Mulheres com menopausa precoce tiveram 48% de maior risco de mortalidade geral (HR=1.48, 95% IC: 1.03, 2.14) comparadas às mulheres com idade de menopausa entre os 50 e 54 anos (referência). Em relação à mortalidade específica, mulheres entre 41 e 49 anos apresentaram o dobro de risco de mortalidade por neoplasias em comparação com o grupo de referência. No terceiro artigo, foi realizada uma revisão sistemática e meta-análise dos fatores reprodutivos associados à menopausa natural. Os três fatores estudados apresentaram uma associação com a menopausa tardia. As mulheres com uso de anticoncepcionais orais em relação àquelas que não relataram uso de anticoncepcionais orais (HR=0.86, CI=0.79, 0.92), as com idade da menarca >=13 anos comparadas àquelas com idade da menarca <13 anos (HR=0.88, CI=0.84, 0.93) e aquelas que relataram ter um filho ou mais comparadas com as que não tiveram filhos (HR=0.80, CI=0.76, 0.85). / Introduction: The increase of the elderly population in Brazil has raised concerns about their care and the determinants of survival and incidence of chronic diseases. Menopause is defined as the permanent end of a woman\'s menstruation and is associated with the decline of the release of estrogens due to loss of follicular function, indicating the end of the reproductive phase of a woman\'s life. Age at menopause has been linked with mortality and morbidity in international studies. The first article of this thesis analyzed the factors associated with age at natural menopause among women of the SABE study cohort (Health, Well-Being, Aging). Smoking and education were associated with earlier menopause for the three waves analyzed: 2000, 2006 and 2010. Current smokers had 35% higher risk of earlier natural menopause (HR=1.35, 95% CI: 1.12, 1.62) and former smokers had 27% higher risk of earlier natural menopause (HR=1.27, 95% CI: 1.09, 1.50), in comparison with never smokers. Regarding education, women with 8 years or more of formal education had 33% lower risk of earlier natural menopause (HR=0.67, 95% CI: 0.50, 0.89) than women with no education. Marital status and parity were associated with later age at natural menopause only in 2006. In the second article, a survival analysis was performed according to age at natural menopause in women from SABE 2000. We found a total of 444 deaths from 2000 to 2016. Women with earlier menopause had 48% increased risk of all-cause mortality (HR=1.48, 95% IC: 1.03, 2.14) compared to women with age at menopause between 50 and 54 years (reference group). Regarding cause-specific mortality, women with ages at natural menopause between 41 and 49 had twice the risk of cancer mortality compared to the reference group. In the third article, we performed a systematic review and meta-analysis of the reproductive factors associated with natural menopause. The three factors analyzed were statistically associated with later menopause: women with use of oral contraceptives before menopause compared to women with no use of oral contraceptive (HR=0.86, CI=0.79, 0.92), women with age at menarche >=13 compared to women with age at menarche <13 years (HR=0.88, CI=0.84, 0.93) and those with one or more live births compared to nulliparous women (HR=0.80, CI=0.76, 0.85).

Diese Dissertation beschäftigt sich mit der Suche nach dem skalaren Top Quark (stop) und dem skalaren Bottom Quark (sbottom) innerhalb des Minimal Supersymmetric Standard Model (MSSM) unter der Annahme der R-Paritätserhaltung. Suchen nach den folgenden Zerfallsmoden des Stop-Quark wurden durchgeführt: stop -> c neutralino_1, stop -> b l sneutrino (wobei l mit gleichen Wahrscheinlichkeiten entweder electron, muon oder tau-lepton ist) und stop -> b tau sneutrino (nur das Tau-Lepton wird berücksichtigt). Zusätzlich wurde der Dreikörperzerfall stop -> b W neutralino_1 im erlaubten Massenbereich M_stop > M_b + M_W + M_neutralino1 >= 86 GeV gesucht. Für das Sbottom-Quark wurde der Zerfall sbottom -> b neutralino_1 studiert. Jede dieser Zerfallsmoden wurde voneinander unabhängig unter der Annahme eines 100 %-igen Verzweigungsverhältnisses untersucht. Für diese Suche wurden Daten aus electron-positron-Kollisionen bei Schwerpunktsenergien im Bereich von 202-208 GeV benutzt. Die Daten wurden im Jahr 2000 von dem L3 Detektor am Large Electron Positron Collider (LEP) am CERN aufgenommen. Ferner wurden die Resultate der Datenanalyse aus dem Jahr 2000 mit Resultaten der Squark-Suche kombiniert, die die L3 Kollaboration in vorhergehenden Jahren bei Schwerpunktsenergien von 161 bis 202 GeV durchgeführt hat. Die untersuchten Squark Zerfallskanäle bestimmen die Topologie der für uns interessanten Ereignisse: 2 Jets (oder b-Jets) + fehlende Energie (+ 2 Leptonen für die Stop-Dreikörperzerfälle). Die stop -> b W neutralino_1 Zerfallstopologie hängt signifikant von den weiteren Zerfällen des W-Bosons ab und kann bis zu 6 Jets im Endzustand haben. Die Annahme der R-Paritätserhaltung impliziert die Stabilität des leichtesten supersymmetrischen Teilchens (des LSP), das das leichteste Neutralino ist. Das LSP wechselwirkt nur schwach und entweicht deswegen unentdeckt. Ein besonderes Merkmal der Signal-Ereignisse ist somit eine erhebliche Menge fehlender Energie. Die sichtbare Energie ist in etwa proportional zu der Massendifferenz zwischen dem Squark und dem LSP. Weil die Standardmodell-Untergrundzusammensetzung vom Anteil der sichtbaren Energie abhängt, hängt die Analyse auch vom Wert von der Massendifferenz ab. Abhängig von der Menge fehlender Energie kann der Standardmodell-Untergrund in drei Kategorien eingeteilt werden: - die zwei-Fermion-Prozesse sind e e -> e e, e e -> mu mu, e e -> tau tau und e e -> e e q q; - die vier-Fermion-Kategorie besteht aus e e -> W W, e e -> W e nu, e e -> Z Z und e e -> Z e e Prozessen; - die zwei-Photon-Untergrundprozesse sind e e -> e e e e, e e -> e e mu mu, e e -> e e tau tau und e e -> e e q q. Der letzte Prozess, e e -> e e q q, trägt den grössten Anteil zu den SM-Untergrundprozessen bei (wegen sehr hohem und stark schwankendem E_miss und dem grössten Wirkungsquerschnitt). Im ersten Schritt der Analyse wurden Events mit der gewünschten Topologie (2 Jets und hohes E_miss) vorselektiert. Die Selektion von Stop- und Sbottom-Ereignissen wurde durch die Minimierung der mit 95 % Confidence Level (C.L.) erwarteten oberen Grenze des Squark-Wirkungsquerschnitts - berechnet aus MC-Vorhersagen - optimiert, wobei der kleine theoretisch vorhergesagte Produktionswirkungsquerschnitt des Squarks berücksichtigt wurde. In allen für den jeweiligen Squark Zerfallskanal optimierten Selektionen stimmt die Anzahl von Daten Events mit der erwarteten Anzahl von Standardmodellprozessen überein: - für den stop -> c neutralino_1 Zerfall wurden 29 Daten-Events beobachtet, wobei 26.5 +- 2.7 Events von den SM-Prozessen erwartet wurden; - für den Dreikörperzerfall stop -> b l sneutrino, wurden 4 Daten-Events selektiert bei einer Standardmodell-Erwartung von 4.0 +- 1.0 Events; - für den Zerfall stop -> b tau sneutrino sind die Daten- und SM-Eventzahlen 5 bzw. 3.9 +- 1.0; - in der Selektion für stop -> b W neutralino_1, wurden 184 Daten Events beobachtet und 181.6 +- 3.0 Events wurden vom Standardmodell vorhergesagt; - für den Bottom Squark Zerfall sbottom -> b neutralino_1 entsprachen die beobachteten 6 Events der SM-Erwartung von 7.7 +- 1.3 Events. Es wurden keine MSSM-Skalar-Quarks in den Daten des Experiments beobachtet und das Resultat der Suche ist negativ. Die modellunabhängige 95 % C.L. obere Grenze für den Squark-Produktionswirkungsquerschnitt wurde aus der gemessenen Anzahl von Daten-Events und der aus dem Standardmodell erwarteten Eventanzahl berechnet. Für die Berechnung der oberen Grenzen der Produktionswirkungsquerschnitte wurden die Resultate der Squark-Suchen aus den L3-Daten bei Schwerpunktsenergien von c.m.s. Energie 202 - 208 GeV mit den Resultaten aus vorherigen Suchen der L3-Kollaboration bei 161 GeV - 202 GeV kombiniert. Eine neue Methode wurde entwickelt, um die kombinierten Grenzen zu berechnen. Die Methode berücksichtigt die statistische Unabhängigkeit jeder Messung und die Abhängigkeit des Squark-Produktionswirkungsquerschnittes von der Schwerpunktsenergie. In der Berechnung wurde den systematischen Unsicherheiten in der Standardmodell-Untergrundabschätzung und der Signal-Selektionseffizienz Rechnung getragen. Für die hier betrachteten Squark-Zerfälle werden typisch folgende oberen Grenzen mit 95 % C.L. für den Squark Produktionswirkungsquerschnitt erhalten: ~ 0.05-0.2 pb (für stop) und ~ 0.05-0.1 pb (für sbottom). Bei den Suchen nach dem Stop-Dreikörperzerfall stop -> b W neutralino_1 wurden die Produktionswirkungsquerschnitte über 0.7-1.0 pb mit 95 % C.L. ausgeschlossen. Innerhalb des Minimal Supersymmetrischen Standard Modells mit R-Paritätserhaltung wurden die unabhängigen Wirkungsquerschnittsgrenzen für den Ausschluss von MSSM Parametern benutzt, insbesondere für die Stop- und Sbottom-Massen. Die Squark-Massen wurden für jeden betrachteten Zerfallskanal in zwei möglichen Szenarien ausgeschlossen: für den maximalen und den (näherungsweise) minimalen theoretischen Wirkungsquerschnitt. Der erste Fall korrespondiert zur maximalen Mischung zwischen den links- und rechtshändigen Squark-Eigenzuständen, $\cos\theta_{LR}$ = 1; der zweite Fall ist definiert durch den Wert von $\cos\theta_{LR}$, bei dem die Squarks vom $Z^0$ Boson entkoppeln. Abhängig vom Wert $\Delta M$ wurden die Squark Massen mit 95 % C.L. bis zu den folgenden Werten ausgeschlossen: - für stop -> c neutralino_1: M_stop < 90-93 GeV (min. Wirkungsquerschnitt), M_stop < 95-96 GeV (max. Wirkungsquerschnitt), - für stop -> b l sneutrino: M_stop < 87-89 GeV (min. Wirkungsquerschnitt), M_stop < 90-91 GeV (max. Wirkungsquerschnitt), - für stop -> b tau sneutrino: M_stop < 83-88 GeV (min. Wirkungsquerschnitt), M_stop < 88-91 GeV (max. Wirkungsquerschnitt), - für sbottom -> b neutralino_1: M_stop < 76-83 GeV (min. Wirkungsquerschnitt), M_stop < 94-97 GeV (max. Wirkungsquerschnitt), In beiden Fällen werden die experimentell beobachteten 95 % C.L. Massen Ausschlussgrenzen mit den aus Monte Carlo Simulationen ohne SUSY Teilchen erwarteten verglichen. Die experimentallen Ausschlussgrenzen Sind verträglich mit den erwarteten. Die mit 95 % C.L. erhaltene obere Grenze für den Stop-Produktionquerschnitt ist im Zerfall stop -> b W neutralino_1 grösser als die zugehörige theoretische Vorhersage. Der Ausschluss mit 95 % C.L. auf Massen war mit dem zur Verfügung stehenden Datensatz aus diesen Grund nicht möglich. Unter der Annahme, dass die Zerfallstopologie der skalaren Quarks der ersten zwei Generationen ähnlich dem Zweikörperzerfall des Stop ist, wurden die Resultate der Suche nach dem Zerfall stop -> c neutralino_1 auch für die Berechnung der Massenausschlussgrenzen für die Squarks der ersten beiden Familien benutzt. Zwei Möglichkeiten wurden hier in Erwägung gezogen: die Massenentartung zwischen vier (scalar u, d, c, s) und fünf (sbottom zusätzlich) Squarks. Die Ausschlussgrenzen mit 95 % C.L. auf die massenentarteten skalaren Quarks in den Fällen der "nur-rechts" oder "links-und-rechts" Eigenzustände sind die folgenden: - für die Massenentartung zwischen vier Squarks: M_squark < 95-96 GeV ("nur-rechts"), M_squark < 99-100 GeV ("links-und-rechts"); - für die Massenentartung zwischen fünf Squarks: M_squark < 96-97 GeV ("nur-rechts"), M_squark < 99-101 GeV ("links-und-rechts"); Mit der Annahme der Gaugino-Vereinigung an der GUT-Skala im MSSM wurden die Grenzen für die vierfach massenentarteten Squarks erneut in der Squark-Gluino Ebene interpretiert. Ferner wurde das absolute Limit auf den MSSM-Parameter M_2, der für tan(beta) = 4 aus anderen L3-SUSY-Suchen (für Chargino, Neutralino und skalare Leptonen) ermittelt worden ist, in ein Gluino-Massenlimit übersetzt. Die mit 95 % C.L. erhaltenen Ausschlussgrenzen in der Squark-Gluino Massenebene sind - M_gluino > 267-314 GeV, - M_squark > 99-100 GeV. / This thesis is devoted to searches for the scalar top and the scalar bottom quarks within the framework of the Minimal Supersymmetric Standard Model (MSSM) with the assumption of R-parity conservation. Searches for the following decay modes of the stop quark have been performed: stop -> c neutralino_1, stop -> b l sneutrino, (where l is either electron, muon or tau-lepton with equal probabilities) and stop -> b tau sneutrino (where only the tau-lepton is considered). In addition, a three body decay stop -> b W neutralino_1 has been searched for in the allowed mass region of M_stop > M_b + M_W + M_neutralino1 >= 86 GeV. For the sbottom quark the decay sbottom -> b neutralino_1 was considered. Each of these decay modes was considered independently assuming a branching ratio of 100 %. For this search, the experimental data of electron-positron collisions at center-of-mass energies (c.m.s.) in the range of 202-208 GeV have been used. These data were collected in the year 2000 by the L3 detector at the Large Electron Positron Collider (LEP) at CERN. The results of the year 2000 data analysis were also combined with results of the squark searches performed by the L3 Collaboration in previous years at center-of-mass energies from 161 up to 202 GeV. The analyzed squark decay channels determine the topology of the events of our interest: 2 jets (or b-jets) + missing energy (+ 2 leptons for stop three body decays). The stop -> b W neutralino_1 decay topology depends significantly on the further decay of the W boson and can have up to 6 jets in the final state. The assumed conservation of R-parity implies stability of the lightest supersymmetric particle (the LSP), which is the lightest neutralino. The LSP interacts only weakly and thus escapes undetected. This leads to a large missing energy as a feature of the signal events. The visible energy is roughly proportional to the difference between the masses of the squark and the LSP, and since the Standard Model background composition depends on the visible energy fraction, the whole analysis depends also on the value of this mass difference. Depending on the magnitude of visible energy, the Standard Model background can be grouped into three categories: - the two-fermion processes are e e -> e e, e e -> mu mu, e e -> tau tau and e e -> q q; - the four-fermion category is composed of e e -> W W, e e -> W e nu, e e -> Z Z and e e -> Z e e processes; - the two-photon background processes are e e -> e e e e, e e -> e e mu mu, e e -> e e tau tau and e e -> e e q q. The last process, e e -> e e q q, constitutes the largest fraction of all SM background processes (due to very high and highly fluctuating missing energy and the highest cross section). At the very first step of the analysis, only the events of interesting topology (with 2 jets and high missing energy) were preselected. Then, taking into account the small value of the theoretically predicted production cross section of the scalar quarks, the selection of stop and sbottom events was optimized by minimization of the 95 % confidence level expected upper limit on the squark cross section using calculated Monte Carlo events. In all selections optimized for each particular squark decay channel, the number of selected data events statistically agrees with the number of events expected from the Standard Model processes: - for stop -> c neutralino_1 decay, 29 data evens were observed, while 26.5 +- 2.7 were expected from the SM processes; - for the three body decay stop -> b l sneutrino, 4 data events were selected and the expectation from the Standard Model is 4.0 +- 1.0 events; - for the decay stop -> b tau sneutrino, the data and SM event numbers are 5 and 3.9 +- 1.0, respectively; - in the selection for stop -> b W neutralino_1, 184 data events were observed and 181.6 +- 3.0 were expected from the Standard Model; - for the bottom squark decay sbottom -> b neutralino_1 the observed 6 events correspond to the SM expectation of 7.7 +- 1.3. Thus, the MSSM scalar quarks were not observed in the experimental data and the search results are negative. The model independent 95 % C.L. upper limits on the squark production cross section have been derived from the numbers of the observed data events and numbers of events expected from the Standard Model. For calculation of the upper cross section limits, the results of the squark searches performed in the L3 data of c.m.s. energy 202 - 208 GeV were combined with results of searches performed by the L3 Collaboration previously in the data of c.m.s. energy from 161 up to 202 GeV. A new method has been developed for calculating such combined limits. This method takes into account the statistical independence of each measurement and the dependency of the squark production cross section on the center-of-mass energy. In this calculation, the systematic uncertainties in the Standard Model background estimation and in the signal selection efficiency have been also accounted for. For the considered squark decays, the typical obtained 95 % C.L. upper limits on the squark production cross section are: ~ 0.05-0.2 pb (for stop) and ~ 0.05-0.1 pb (for sbottom). In the searches for the stop three body decay stop -> b W neutralino_1, the cross sections above 0.7-1.0 pb have been excluded at 95 % C.L. Within the framework of MSSM with conserved R-parity, the experimental model independent cross section limits have been used for exclusion of the MSSM model parameters, in particular, exclusion of the stop and the sbottom masses. For each considered decay channel, the squark masses have been excluded in two possible scenarios: for the maximal and for the (approximately) minimal theoretical cross section. The first case corresponds to the maximal mixing between the left and right squark eigenstates, cos(theta) = 1; the second case is defined by the cos(theta) value, where squarks decouple from the Z boson. Depending on the mass difference between squark and the LSP, the squark masses have been excluded at 95 % C.L. up to the following values: - for stop -> c neutralino_1: M_stop < 90-93 GeV for minimal cross section, M_stop < 95-96 GeV for maximal cross section; - for stop -> b l sneutrino: M_stop < 87-89 GeV for minimal cross section, M_stop < 90-91 GeV for maximal cross section; - for stop -> b tau sneutrino: M_stop < 83-88 GeV for minimal cross section, M_stop < 88-91 GeV for maximal cross section; - for sbottom -> b neutralino_1: M_stop < 76-83 GeV for minimal cross section, M_stop < 94-97 GeV for maximal cross section. For both cases, the experimentally observed 95 \% C.L. mass exclusions are compared to the expected ones, which have been obtained from the Monte-Carlo assuming no SUSY particles. The observed exclusions of the squark masses are at the same level as the expected ones. The obtained 95 % C.L. upper limits on the stop production cross section in the decay stop -> b W neutralino_1 are bigger than the corresponding theoretical predictions, so, the exclusion of masses at 95 % C.L. was not possible with the available data sample. Assuming the topology of decays of the scalar quarks of the first two generations to be similar to the two body decay of the stop, the results of the searches for the decay stop -> c neutralino_1 have been also used for calculation of the mass exclusion limits for the squarks of the first two families. Two possibilities were considered here: the mass degeneracy between four (scalar u, d, c, s) and five (scalar b in addition) squarks. The 95 % C.L. exclusion limits on the mass degenerate scalar quarks for the cases of the "right-only" or "left-and-right" eigenstates are the following: - for the mass degeneration between 4 squarks: M_squark < 95-96 GeV ("right-only"), M_squark < 99-100 GeV ("left-and-right"); - for the mass degeneration between 5 squarks: M_squark < 96-97 GeV ("right-only"), M_squark < 99-101 GeV ("left-and-right"). Using the MSSM assumption about gaugino unification at the GUT scale, the limits on the four mass degenerate squarks have been reinterpreted on the squark-gluino mass plane. Moreover, the absolute limit on the MSSM parameter M_2, obtained for tan(beta) = 4 from other L3 SUSY searches (for chargino, neutralino and scalar leptons), has been translated into a gluino mass limit. The obtained 95 % C.L. exclusions in the squark-gluino mass plane are - M_gluino > 267-314 GeV, - M_squark > 99-100 GeV.

Dans cette thèse, deux problèmes liés aux approches basées sur des modèles pour le diagnostic de défauts et l'estimation du niveau de dégradation des équipements dans un bâtiment sont étudiés: la conception d'observateurs adaptatifs pour l'estimation de l'état et des paramètres, et l'analyse de l'identifiabilité des paramètres. La classe des modèles considérés est celle des modèles quasi-linéaires à paramètres variants dans le temps (quasi-LPV) avec paramétrisation affine des matrices d'état. Utilisant l'approche polytopique de Takagi-Sugeno (T-S), deux types d'observateurs sont proposés, un pour des systèmes en temps continu et l'autre pour des systèmes en temps discret. La structure de Luenberger (correction de la dynamique à l'aide de l'erreur d'estimation de la sortie) est choisie pour la partie d'estimation d'état de l'observateur pour les deux et leur conception s'appuie sur l'approche de Lyapunov. Pour la partie d'estimation des paramètres, une structure originale est proposée en temps continu et une structure proportionnelle-intégrale (PI) est utilisée en temps discret. La troisième contribution présente succinctement une méthode d'estimation d'état et des paramètres de façon découplée. Elle utilise conjointement l'approche de l'espace de parité et un observateur à mémoire finie. Pour la quatrième contribution relative à l'identifiabilité des paramètres, les états du système sont tout d'abord éliminés en utilisant une approche de type espace de parité. Cela permet d'extraire le `résumé exhaustif' du modèle qui aide à établir l'identifiabilité du modèle. Tous les résultats sont illustrés à l'aide d'exemples / Two problems relevant to the model-based approaches to fault diagnosis and degradation estimation in commissioned buildings are investigated in this thesis: adaptive observers for state and parameter estimation, and parameter identifiability. The system models considered are the quasi-LPV models with affine parameterization. Using the Takagi-Sugeno (T-S) polytopic approach, two observer designs, one for continuous-time models and another for discrete-time models are provided. Both models use a Luenberger structure for the state estimation part and deploy the Lyapunov design approach. An innovative non-linear estimation model is obtained through the design process for the continuous-time parameter estimation whereas a proportional-integral (PI) structure is used for discrete-time. A brief third contribution is a decoupled state and parameter estimation that makes use of the parity-space approach and realized using a finite memory observer strategy. For the fourth contribution of parameter identifiability, a parity-space formulation using null-space computation is used for the elimination of states of the model from which the exhaustive summary of the model is extracted and the identifiability of the model verified. All the results are illustrated using examples