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This thesis report presents a new design of a synchronization unit for high power impulse magnetron sputtering (HiPIMS) applications used for depositing thin films. The proposed system is composed of two major hardware parts: a microcontroller unit (MCU) and a field-programmable gate array (FPGA). The control range of the new system is increased by at least ten times compared to existing synchronization unit designed by Ionautics AB.In order to verify the system and benchmark its innovations, several batches of the thin film have been deposited using the new technology. It is shown that HiPIMS with synchronized pulsed substrate bias can effectively improve coating performance. Pulsed substrate bias with user-defined pulse width and delay time is possible to use in the new control mode proposed by this master thesis work; Bias mode. As a result, this master thesis work enables users to flexibly control the HiPIMS processes.

Die vorliegende Arbeit ist der Verbesserung der Carrier-Envelope Phasenstabilisierung von ultrakurzen Laserimpulsen gewidmet. Zur Realisierung von Fortschritten auf diesem Gebiet werden die grundlegenden Rauschquellen identifiziert, die das erzielbare Restphasenrauschen limitieren, und geeignete Maßnahmen zu deren Verringerung vorgeschlagen. Es wird gezeigt, dass sowohl die Messung der Carrier-Envelope Phase (CEP) als auch deren Kontrolle durch verschiedene Rauschbeiträge beeinträchtigt wird. Der Detektionsprozess ist dabei einerseits durch technische Rauschquellen beeinflusst, die vor allem in den verwendeten nichtlinearen Interferometern auftreten. Andererseits repräsentiert das Detektionsrauschen während der elektro-optischen Wandlung eine fundamentale Limitierung, da das optische Schrotrauschen sowie das Rauschen des Lichtdetektors die Messung der CEP unausweichlich beeinträchtigen. Es wird demonstriert, wie solche Beschränkungen durch geeignete Wahl der Interferometertopologie, bzw. durch Optimierung des spektralen Verbreiterungsmechanismus verringert werden können. Experimentell gelingt es dadurch den Signal-Rauschabstand der Phasenmessung um 20 Dezibel zu steigern. Hinsichtlich der CEP Kontrolle von Oszillatoren wird in dieser Arbeit ein neuartiges Doppelstabilisierungskonzept vorgestellt, welches eine feed-forward Stabilisierung, die auf einem akustooptischen Frequenzschieber beruht, mit einer klassischen Feedback Regelung kombinert. Mit diesem Konzept gelingt eine Reduzierung des Phasenrestrauschen auf beispiellose 20 Milliradian. Darüber hinaus werden weitere neue Stabilisierungskonzepte vorgestellt, die ohne Feedback zu dem Laseroszillator auskommen. Bei einem dieser Konzepte, handelt es sich um eine gepulste feed-forward Stabilisierung, die speziell für das Zusammenwirken mit einer Verstärkerstufe konzipiert ist. Erste experimentelle Ergebnisse zeigen, dass Phasenrestrauschen von weniger als 100 Milliradian auch für Verstärkersysteme erreichbar sind. / The present thesis is dedicated to improvements of the carrier-envelope phase stabilization of ultrashort laser pulses. In order to realize such improvements, the fundamental noise sources are identified, and suitable measures for their reduction are proposed. It is shown that both, the measurement of the carrier-envelope phase (CEP) as well as its control are corrupted by different noise contributions. On the one hand, the detection process is influenced by technical noise sources, which arise especially in the used nonlinear interferometers. On the other hand, the detection noise in the electro-optic conversion represents a fundamental limitation, since the optical shot noise as well as the noise induced by the light detector inevitably influence the measurement of the CEP. It is demonstrated how such limitations can be minimized by a suitable choice of the interferometer topology and by an optimization of the spectral broadening process in a micro-structured fiber. This way an enormous improvement of the signal-to-noise ratio by 20 dB is obtained experimentally, which significantly reduces the limitation of detection noise. For controlling the CEP of mode-locked oscillators, a novel double stabilization scheme is introduced in this thesis, which combines a feed-forward stabilization based on an acousto-optic frequency shifter, with a classical feedback loop. This method enables a reduction of the residual phase jitter to an unprecedented value of 20 milliradian. Beyond that, several further concepts are introduced that are capable of stabilizing the CEP without any feedback to the laser oscillator. One of these concepts, represents a pulsed feed-forward stabilization, which is specifically designed for the use in combination with a subsequent amplification stage. First experimental results indicate that residual phase jitters of less than 100 milliradian are within reach also for amplified laser systems.

The human vestibulo-ocular reflex (VOR) stabilizes gaze during head movement. The reflex is typically tested in a clinic or laboratory using passive rotations or artificial stimuli which measure the amount of damage the vestibular apparatus has suffered. However, during everyday activities the vestibular system is stimulated by active, self generated head movements. Head movements are often rapid and associated with the goal of achieving either gaze-fixation or re-fixation. Patients who complain of on-going symptoms will typically identify a particular position or movement that aggravates their symptoms in their everyday life. There is a need to identify objective parameters which correlate with the subjective complaints of patients whose symptoms persist after vestibular damage. In the first study, a gaze-refixation task, patients who complain of ongoing symptoms (poorly-compensated), during rapid head turns, after unilateral vestibular de-afferentation (uVD) were compared with those who did not have the same complaints (well-compensated) and normal subjects. Well- and poorly-compensated groups were sorted according to responses on a standardized questionnaire. All subjects were then located in a real-world, non-laboratory environment in which poorly-compensated subjects reported experiencing symptoms. Each subject’s head, eye and gaze displacement and velocity, head rotation frequency and blink or eye-lid closure were measured and analysed and compared between ipsi- and contra-lesional head rotations within and between subject groups. When subjects are able to generate their own active head rotations it has been suggested that a number of vestibular and extra-vestibular strategies might be employed to compensate for an impaired VOR. In subsequent studies, high resolution scleral search coils were used to identify the compensatory mechanisms used during active head rotations during a gaze-fixation task. A corrective saccade is typically observed during passive ipsilesional head rotations or “impulses” and might be potentiated during rapid, active or self-generated head rotations. The conditions which predict or contribute to the generation of the rapid, corrective eye movement were investigated. The results were compared with responses to passive head impulses of matched velocity and acceleration to determine if active head impulses could be used to identify a lesioned vestibular apparatus as is routinely clinically achieved with passive head impulses.

實務界多將監視制度之實施效果定義為防止操縱市場。的確，國內股市一向投機氣氛濃厚、短線交易盛行，惟異常交易未必全導因於投機炒作，事實上，股市交易者交易目的有四種：一是風險分攤(risk sharing)，二是變現性交易(liquidity tradings)，三是具有訊息基礎的交易(information-based tradings)，四是炒作(manipulation)。異常交易宣告訊息在實證上，可以同時作為最可能發生市場訊息不對稱的樣本組，異常交易之肇致，究竟是否純係炒作造成，抑或具有訊息基礎的交易亦佔若干比重，應是一有趣之研究課題。 　　以下研究主題為本研究之重心： 　　1.在公告警示股票的漲跌方向，分為合併與漲幅、跌幅三類宣告來計算其累積異常報酬。 　　2.檢視股價之超額報酬與警示之宣告有無干預之效果。 　　3.檢視警示股票在警示前後其對訊息之衝擊反應有無差異，並探討警示宣告對股票之價格資訊性之影響。 　　4.檢視警示股票與非警示股票在對訊息之衝擊有無反應上的差異。 　　5.檢視警示股票對不同的交易量造成股票買賣價差的衝擊。 　　6.檢視前後期價格變動與前後期交易量之因果關係。 　　本研究有以下結論： 　　結論1.畢竟警示門檻為公開資訊，一異常交易投在警示宣告前，市場應可預期，而不應在警示後存在任何方向之顯著異常報酬；國內股票市場仍不能稱具有半強式效率。 　　結論2.股票受警示後具負異常報酬，顯示警示制度對飆漲股票確有干預作用。 　　結論3.警示前後一張一千股買單，所呈現之訊息大小好壞沒有差異。 　　結論4.在警示股與非警示股間一張一千股買單，對警示般的衝擊較大，顯示警示股對訊息反應較敏感。 　　結論5.警示股的報價修正與價差之影響都和買單大小成正比，股票普遍存在當期價量有回饋關係，前一期是當期價量關係之前因。顯示Information-based確為肇致異常交易之主因。 　　結論6.警示宣告後，訊息不對稱仍然存在，且不見有效降低。 　　結論7.警示後交易者對股價認知變異增加，由投資者對價差之調整過程可看出警示後投資者之過度反應的行為。有此現象可能因為有投資者認為是明牌股而購買，也有投資者怕因高風險而導致損失，故及早出脫，因此對股價有兩極化的看法。 　　結論8.警示宣告後，買單追隨買單情形降低，可能是風險增加導致原追買追賣交易者轉趨保守。

<p>A wave digital filter is derived from an analog filter, which is realized as classical doubly resistively terminated reactancefilters. Perfectly designed wave digital filters express good dynamic signal range, low roundoff noise and excellent stabilitycharacteristics with respect to nonlinearity which are produced due to finite wordlength effects. Wave digital filters inheritthe sensitivity properties from analog filters, therefore, coefficients values can be selected to favorable values.Wave digital filters, derived from ladder filters, have low coefficient sensitivity in the passband and stopband. These WDFsare very complicated and are non-modular. The lattice wave digital filters are modular and are not complex. However, theyhave very high sensitivity in the stopband and thus require large coefficient wordlengths. The number of coefficients equalsthe filter order which have to be odd.This thesis discusses the wave digital filter structures that are modular because they are designed by cascading the first-orderand second-order sections. These WDFs can be pipelined. They also exhibit all the above mentioned favorable properties.Similar to lattice WDFs, these structures are restricted to symmetrical and antisymmetrical transfer functions. The synthesisof these structures is based on the factorization of the scattering matrix of lossless two-ports.In this thesis work, lowpass wave digital filters based on circulator-tree structure are designed with different orders startingfrom 3 and going upto 13. In parallel to these circulator-tree wave digital filters, the simple digital filters are also designedwith the same specification. The results of the two filters are compared with each other. It is observed that impulse responseand attenuation response of the two kind of filters perfectly match. Therefore, it is can be concluded that circulator-tree WDFupto Nth order can be synthesized. The implementation examples of two filter with order 3 and order 7 is presented in thisdocumentation for ready reference. It has also been shown that the order of sections does not affect the transfer function ofthe filter. Noise has been introduced and adaptor sections are penetrated. From the results it is concluded that the order of theadaptor sections does not matter and also that the noise does not affect the other adaptors sections, it only propagates throughother adaptors sections.</p>

Poor athletic performance of racehorses is a major and significant problem in the racing industry. Determining the definitive reason for poor-performance is however a real diagnostic challenge since many of the causative conditions are multifactorial and may only be manifested during exercise. A retrospective study, including various breeds of horses, confirmed musculoskeletal, cardiovascular and upper respiratory tract clinical problems to be the most frequently implicated in reducing athletic performance. Evaluation of the lower respiratory tract was though not performed in this study. The aim of the first part of this work were thus to determine the prevalence of different sub-clinical diseases in a population of poorly-performing Standardbred trotters, and to evaluate the sportive repercussions by comparing their physiological response to exercise with control horses. Fifty horses underwent thorough clinical and ancillary examinations, including haematological et biochemical evaluation, Doppler echocardiography, standardised exercise tests on treadmill et racetrack, treadmill video-endoscopy et collection of respiratory fluids. Most of the poorly-performing horses exhibited many concomitant diseases. The most frequently diagnosed sub-clinical problems involved the lower and upper respiratory tract. Poor-performers also exhibited higher values of blood lactate and heart rate, as well as lower values of haematological parameters and anti-oxidants, compared to control horses. Inflammatory airway disease being mostly present in poorly-performing horses, the second part of this work will mainly focus on this syndrome. The negative impact of inflammatory airway disease, as diagnosed by cytological evaluation of bronchoalveolar lavage fluid, has previously been described on respiratory function using either forced expiration or forced oscillations techniques. Sedation or bronchoprovocation were however usually required. On the other hand, the clinical significance of tracheal inflammation remains currently controversial. The aim was therefore to exhibit and define the respiratory dysfunctions present in horses subclinically suffering from inflammatory airway disease. Respiratory function was evaluated at rest by IOS in 34 Standardbred trotters, whereas tracheal mucus score, and both tracheal and bronchoalveolar lavages were performed 60 min post-exercise. According to the cytology of bronchoalveolar lavage fluid, the inflammatory group included 19 horses and 15 horses were used as control. A significant correlation was found between both cytological evaluations concerning neutrophil counts, whereas no association was found between tracheal mucus and any cytology. A significant increase of respiratory resistance at the lower frequencies (1 10 Hz) as well as a significant decrease of respiratory reactance beyond 5 Hz was observed in inflammatory compared to control horses. Both parameters were also significantly different between inspiration and expiration in the inflammatory group only. Both eosinophil and mast cell counts of the bronchoalveolar lavage fluid were significantly correlated with respectively respiratory resistance and reactance. The present work involved intensive clinical and functional evaluation of control and asymptomatic poorly-performing horses. The different studies allowed establishing the prevalence of medical subclinical diseases in these latter and evaluating its sportive impact considering the associated physiological responses to exercise. The presence of respiratory dysfunctions in horses with lower airway inflammation, the major trouble associated with disappointing performance, were also exhibited by impulse oscillometry./ La contre-performance est un problème majeur dans lindustrie des courses. En déterminer la cause exacte reste néanmoins un défi diagnostic puisque la plupart des affections présentes sont souvent subcliniques, multifactorielles et peuvent ne se manifester que pendant lexercice. Une étude rétrospective, incluant des chevaux de différentes races et disciplines, a ainsi confirmé les affections cliniques des voies respiratoires supérieures, musculo-squelettiques et cardiovasculaires comme étant les plus fréquemment impliquées dans la réduction des performances athlétiques. Cependant, lévaluation des voies respiratoires profondes navait pas été effectuée chez ces différents chevaux. Lobjectif de la première partie de ce travail était donc de déterminer la prévalence des différentes affections sub-cliniques induisant une contre-performance chez des Trotteurs Français, et den évaluer les répercussions sportives par la comparaison des réponses physiologiques à lexercice avec celle de chevaux contrôles. Cinquante chevaux ont respectivement été soumis à un examen clinique complet, une prise de sang pour analyse hémato-biochimique au repos et 60 minutes après chaque test deffort, une échocardiographie Doppler, des tests deffort standardisés sur piste et tapis roulant, une endoscopie à leffort, une évaluation locomotrice à grande vitesse, ainsi quun lavage trachéal et broncho-alvéolaire réalisés 60 minutes post-effort. La plupart des chevaux contre-performants ou intolérants à leffort présentaient plusieurs affections concomitantes. Les troubles sub-cliniques les plus fréquemment diagnostiqués concernaient respectivement les voies respiratoires profondes et supérieures. Ces chevaux présentaient par ailleurs des paramètres hématologiques (taux dhémoglobine et volume globulaire moyen) et anti-oxydants significativement inférieurs, et des paramètres pro-oxydants significativement supérieurs aux chevaux contrôles. De plus, les valeurs de fréquence cardiaque et lactatémie étaient, lors des différents tests deffort, significativement supérieures à celles des chevaux contrôles, Linflammation des voies respiratoires profondes étant majoritairement présente chez ces chevaux présentant des performances décevantes, la deuxième partie de ce travail se concentre plus spécifiquement sur ce syndrome. Limpact négatif sur la fonction respiratoire de cette affection, telle que diagnostiquée par lévaluation cytologique du liquide de lavage broncho-alvéolaire, a précédemment été décrite à laide de techniques dexpiration forcée ou doscillations forcées. Une sédation ou une bronchoprovocation étaient cependant généralement requises pour la réalisation de ces tests. Parallèlement, la signification clinique de linflammation trachéale reste actuellement controversée. Lobjectif était ainsi de mettre en évidence et définir les dysfonctions respiratoires présentes chez des chevaux souffrant sub-cliniquement de maladie inflammatoire des voies respiratoires. La fonction respiratoire a été évaluée au repos par oscillométrie à impulsions chez 34 Trotteurs Français asymptomatiques, alors que le score de mucus trachéal et les différents lavages ont été évalués 60 minutes post-effort. Sur base de la cytologie broncho-alvéolaire, le groupe inflammatoire comprenait 19 chevaux et 15 ont été utilisés comme contrôles. Une corrélation significative était observée entre les cytologies concernant le taux de neutrophiles, alors quaucune association nétait présente entre score de mucus trachéal et cytologies des différents lavages. Une augmentation significative de la résistance respiratoire aux faibles fréquences (1 à 10 Hz) et une diminution de la réactance respiratoire au-delà de 5Hz a été observée chez les chevaux inflammatoires comparativement aux contrôles. Ces deux paramètres étaient également significativement différents entre inspiration et expiration dans le groupe inflammatoire uniquement. La résistance et la réactance respiratoire étaient par ailleurs respectivement corrélées aux taux déosinophiles et de mastocytes du lavage broncho-alvéolaire. Ce travail comprenait une évaluation clinique et fonctionnelle intensive chez des chevaux contrôles et des chevaux contre-performants. Les études menées ont permis détablir la prévalence des affections médicales sub-cliniques chez ces derniers et den évaluer limpact sportif par lintermédiaire des réponses physiologiques à lexercice. La présence de dysfonctions respiratoires chez les chevaux avec inflammation des voies respiratoires profondes, premier trouble associé à des performances décevantes, a également pu être mise en évidence à laide de loscillométrie à impulsion.

A wave digital filter is derived from an analog filter, which is realized as classical doubly resistively terminated reactancefilters. Perfectly designed wave digital filters express good dynamic signal range, low roundoff noise and excellent stabilitycharacteristics with respect to nonlinearity which are produced due to finite wordlength effects. Wave digital filters inheritthe sensitivity properties from analog filters, therefore, coefficients values can be selected to favorable values.Wave digital filters, derived from ladder filters, have low coefficient sensitivity in the passband and stopband. These WDFsare very complicated and are non-modular. The lattice wave digital filters are modular and are not complex. However, theyhave very high sensitivity in the stopband and thus require large coefficient wordlengths. The number of coefficients equalsthe filter order which have to be odd.This thesis discusses the wave digital filter structures that are modular because they are designed by cascading the first-orderand second-order sections. These WDFs can be pipelined. They also exhibit all the above mentioned favorable properties.Similar to lattice WDFs, these structures are restricted to symmetrical and antisymmetrical transfer functions. The synthesisof these structures is based on the factorization of the scattering matrix of lossless two-ports.In this thesis work, lowpass wave digital filters based on circulator-tree structure are designed with different orders startingfrom 3 and going upto 13. In parallel to these circulator-tree wave digital filters, the simple digital filters are also designedwith the same specification. The results of the two filters are compared with each other. It is observed that impulse responseand attenuation response of the two kind of filters perfectly match. Therefore, it is can be concluded that circulator-tree WDFupto Nth order can be synthesized. The implementation examples of two filter with order 3 and order 7 is presented in thisdocumentation for ready reference. It has also been shown that the order of sections does not affect the transfer function ofthe filter. Noise has been introduced and adaptor sections are penetrated. From the results it is concluded that the order of theadaptor sections does not matter and also that the noise does not affect the other adaptors sections, it only propagates throughother adaptors sections.

Timing offsets result from the use of real clocks that are non-ideal in sampling intervals. These offsets also known as timing jitter were shown to degrade the performance of the two forms of UWB systems impulse radio and orthogonal frequency division multiplexing (OFDM)-based UWB. It was shown that for impulse radio, timing jitter distorts the correlation property of the transmitted signal and the resulting performance loss is proportional to the root-mean-square (RMS) value of the timing jitter. For the OFDM-based UWB, timing jitter introduced inter-channel interference (ICI) and the performance loss was dependent on the product of the bandwidth and the RMS of the timing jitter. A number of techniques were proposed for mitigating the performance degradation in each form of UWB. Specifically, for impulse radio, the methods of pulse shaping and sample averaging were provided, whereas for OFDM-based UWB, oversampling and adaptive modulation were given. Through analysis and simulation, it was shown that substantial gain in signal power-to-noise ratio can be achieved using these jitter-reduction methods.