Fault location for series compensated lines cannot be addressed sufficiently by conventional solutions developed for traditional uncompensated lines. Line-parameters vary with loading and weather conditions, and therefore settings used for fault location are often erroneous. Line-parameter free solutions for fault location are therefore more reliable and accurate than conventional solutions that require such settings. Hence, line-parameter free fault location algorithms for single-circuit and double-circuit series compensated transmission lines were developed during the research project. Single-circuit lines and double-circuit lines both present unique challenges for fault location. They also vary in the number of available measurements that can be used to arrive at a solution for distance to fault. A third algorithm is presented that allows the extension of existing short line algorithms to the case of long lines. This is done by providing a method for incorporating the line shunt admittance into these existing algorithms. The aforementioned three bodies of research work, form the focus of this thesis. The algorithms are derived using two-terminal synchronised current and voltage sampled measurements. Of these, the algorithms for series compensated lines are also derived for asynchronous measurements. Phasors are obtained by carrying out a Fast Fourier Transform, and then appropriate calculations are performed for distance to fault. The thesis covers the mathematical derivations of the algorithms, involving the algebraic reduction of non-linear equations in numerous variables into a single expression for distance to fault. The results for a variety of simulation tests are shown subsequently and discussed. Various fault resistances, fault types, degrees of series compensation, line lengths, fault levels are considered in the tests carried out. The algorithms are largely found to be highly accurate under these various conditions, and where the algorithms perform to a lesser degree of accuracy are highlighted and discussed. Lastly, a detailed chapter discussing future work is also included in the thesis.

There is increasing evidence to suggest that fetal events can predetermine reproductive health and general wellbeing in adulthood, a process termed 'fetal programming'. This refers to the association between altered fetal growth/development and health disorders in adulthood e.g. the metabolic syndrome, which is linked to low male testosterone levels. Studies from both Europe and the USA have shown that adult male testosterone levels have been declining, independent of age. As low testosterone levels in aging men are associated with increased morbidity and mortality, this highlights the importance of investigating how testosterone levels are determined or potentially ‘programmed’ during fetal development. Evidence from human and rodent studies have shown that reduced fetal androgen exposure results in lower adult testosterone levels, although the mechanism(s) is unknown, to date. One way to explain how a fetal insult (e.g. androgen deficiency) could affect (testosterone producing) adult Leydig cells in adulthood, is if their progenitor cells were present during fetal life and were thus affected by such an insult. This hypothesis has been unexplored to date, due to the lack of a unifying/defining marker for adult Leydig progenitor cells. An earlier study promoted the hypothesis for the studies in this thesis, namely that chicken ovalbumin upstream promoter transcription factor-II (COUP-TFII) might constitute such a marker, as inducible knockout of COUP-TFII in pre-pubertal male mice results in failure of adult Leydig cells to develop. Therefore, the hypothesis which was explored in this thesis was that 'fetal programming' of COUP-TFII+ adult Leydig progenitor cells prior to their differentiation into adult Leydig cells, would explain how fetal events could predetermine adult testosterone levels. To investigate whether adult Leydig cells (ALC) develop from COUP-TFII+ interstitial cells, firstly an adult Leydig cell ablation/regeneration model was used, which involved a single injection of ethane dimethane sulphonate (EDS). This identified that in rats, ALC derive from COUP-TFII+ interstitial cells which do not express any other phenotypical adult Leydig or interstitial cell markers prior to differentiation. Secondly, COUP-TFII+ adult Leydig progenitor cells are abundant in the fetal testis and conserved across species, including man. Thirdly, fetal interstitial cells which differentiated into ALC, as evident from an ALC lineage tracer model, also expressed COUP-TFII. Overall, these findings suggest that the COUP-TFII+ interstitial cells which differentiate into ALC are 'adult Leydig progenitor cells'. The findings from this thesis also show that the identified adult Leydig progenitor cells express the androgen receptor (AR) in fetal life. Furthermore, experimental reduction of androgen action in fetal life in transgenic mice (AR knockout) or chemical manipulations to reduce fetal testosterone levels (di(n-butyl) phthalate; DBP exposure) resulted in a similar reduction (~40%) in progenitor cell numbers from birth through to adulthood. A parallel reduction of adult Leydig cell numbers across postnatal development was found in mice, but not rats, but as a result of altered fetal androgen action, both models showed evidence for compensated adult Leydig cell failure. This is defined as normal/low testosterone and elevated luteinising hormone (LH) levels. Cell-selective knockout of AR in peritubular myoid (PTM) cells (PTM-ARKO) or Sertoli cells (SC-ARKO) did not affect the numerical development of adult Leydig progenitor cells. To manipulate testicular testosterone action in postnatal life, rats were exposed to a potent AR antagonist, flutamide, which reduced the number of adult Leydig progenitor cells but did not affect ALC number/function. However, the combination of fetal DBP+postnatal flutamide exposure reduced adult Leydig progenitor cells and resulted in compensated ALC failure. Overall, these studies highlight the importance of fetal androgens for the normal development of adult Leydig progenitor cells and for the subsequent development of normally functioning adult Leydig cells. As fetal deficits in androgen exposure resulted in adult Leydig cell dysfunction, this thesis also investigated three separate models to determine whether increased fetal androgen exposure could increase/enhance adult Leydig progenitor cell development, resulting in a 'gain of adult Leydig cell function'. In the first model to increase fetal androgen exposure, pregnant dams injected with testosterone propionate (TP; 20mg/kg/day e14-21.5) were discarded, due to confounding factors including fetal growth restriction and aromatisation of TP. The second model utilised dihydrotestosterone (DHT; 10mg/kg/day), administered to pregnant dams, but there were no effects found in adulthood to male offspring. It was concluded that the administered dose was not sufficient to increase intratesticular testosterone levels in the fetus. The third model utilised an inducible nitric oxide synthase knockout (iNOS-/-) mouse model, for which previous evidence showed increased testis weight, Leydig and Sertoli cell number (~50%), and normal testosterone but low LH levels in adulthood. Stereological quantification showed an increase in the number of adult Leydig progenitor cells in postnatal, but not fetal life, which resulted in the conclusion that the observed changes were a consequence of postnatal effects. Finally, a potential mechanism to explain how DBP-induced androgen deficiency in fetal life, could result in adult Leydig cell dysfunction in adulthood was investigated. Analysis of testicular genes in adulthood, involved in the steroidogenic pathway, showed a reduction in 3b-hsd and StAR. The reduced StAR expression was associated with increased repressive histone methylation (H3K27me3) in its proximal promoter region, as demonstrated by a chromatin immunoprecipitation (ChIP) assay, qPCR, and densitometrical analysis. Accordingly, adult Leydig cells were shown to express increased H3K27me3 by immunohistochemistry, a change also evident in adult Leydig progenitor cells in the fetal testis. This would provide a potential mechanism to explain how fetal events can 'programme' adult Leydig cell testosterone production, namely via an epigenetic change to adult Leydig progenitor cells. In summary, the results in this thesis show how fetal events, including androgen action on progenitor cells, can potentially programme adult Leydig cell function and thus determine testosterone levels. As testosterone is crucial to man, the findings reported in this thesis may have important implications for the general health and longevity of man.

The first topic of this thesis is a novel NTSC video sync separator (NSS) with a high-PSR (power supply rejection) bias generation circuitry (BGC) comprising a temperature compensation circuitry. The proposed BGC is composed of step-down regulators and a bandgap-based bias with cascode current control. The clamping voltages required for sync separation from an NTSC signal are generated. The second topic is a temperature-compensated 6th order transconductance-C (Gm-C) anti-aliasing filter (AAF) with digitally tunable bandwidth which can be applied in the analog front-end circuit of DVB-T receivers. The proposed AAF is controlled by digital signals to provide three different baseband bandwidth (6, 7, 8 MHz) selection. A regulator with a bandgap circuitry supplies a stable voltage to suppress the variations of power and temperature. Moreover, a temperature -compensated circuitry is used to neutralize bandwidth drifting caused by the temperature variation. The bandwidth accuracy of the proposed design verified by HSPICE post-layout simulations is better than 3.28% at every PVT (process, supply voltage, temperature) corner. It is adequate for the DVB-T receivers¡¦ baseband processing.

The objectives of this research are to accomplish Multilayer Ceramic Capacitors, MLCCs used Temperature compensated type Ceramic powder and different design and size to confer its characteristic. The first to speak about Taiwan capacitors property development to point Multilayer Ceramic Capacitors from 1960 to recently.The manufacture procedure from Normal Metal Electronic procedure change to Base Metal Electronic procedure. The second to quote the relation document to explain Temperature compensated type Multilayer Ceramic Capacitors characteristics and main electric characteristics and the related factors such as Frequency, Test Signal Level, DC Bias, Temperature, Time, Insulation resistance and Break down voltage. The last from sample manufacture flow and structure analysis to electric characteristic measure analysis and result to discuss opposite factor characteristics. To bring up develop direction and reference material.

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Die vorliegende Dissertation befasst sich mit der mathematischen Modellierung semi-klassischer Licht-Materie-Interaktion. Im semiklassischen Bild wird Materie durch eine Dichtematrix "rho" beschrieben. Das Konzept der Dichtematrizen ist quantenmechanischer Natur. Auf der anderen Seite wird Licht durch ein klassisches elektromagnetisches Feld "(E,H)" beschrieben. Wir stellen einen mathematischen Rahmen vor, in dem wir systematisch dissipative Effekte in die Liouville-von-Neumann-Gleichung inkludieren. Bei unserem Ansatz sticht ins Auge, dass Lösungen der resultierenden Gleichung eine intrinsische Liapunov-Funktion besitzen. Anschließend koppeln wir die resultierende Gleichung mit den Maxwell-Gleichungen und erhalten ein neues selbstkonsistentes, dissipatives Modell vom Maxwell-Bloch-Typ. Der Fokus dieser Arbeit liegt auf der intensiven mathematischen Studie des dissipativen Modells vom Maxwell-Bloch-Typ. Da das Modell Lipschitz-Stetigkeit vermissen lassen, kreieren wir eine regularisierte Version des Modells, das Lipschitz-stetig ist. Wir beschränken unsere Analyse im Wesentlichen auf die Lipschitz-stetige Regularisierung. Für regularisierte Versionen des dissipativen Modells zeigen wir die Existenz von Lösungen des zugehörigen Anfangswertproblems. Der Kern des Existenzbeweises besteht aus einem Resultat von ``compensated compactness'''', das von P. Gérard bewiesen wurde, sowie aus einem Lemma vom Rellich-Typ. In Teilen folgt dieser Beweis dem Vorgehen einer älteren Arbeit von J.-L. Joly, G. Métivier und J. Rauch. / This thesis deals with the mathematical modeling of semi-classical matter-light interaction. In the semi-classical picture, matter is described by a density matrix "rho", a quantum mechanical concept. Light on the other hand, is described by a classical electromagnetic field "(E,H)". We give a short overview of the physical background, introduce the usual coupling mechanism and derive the classical Maxwell-Bloch equations which have intensively been studied in the literature. Moreover, We introduce a mathematical framework in which we state a systematic approach to include dissipative effects in the Liouville-von-Neumann equation. The striking advantage of our approach is the intrinsic existence of a Liapunov function for solutions to the resulting evolution equation. Next, we couple the resulting equation to the Maxwell equations and arrive at a new self-consistent dissipative Maxwell-Bloch type model for semi-classical matter-light interaction. The main focus of this work lies on the intensive mathematical study of the dissipative Maxwell-Bloch type model. Since our model lacks Lipschitz continuity, we create a regularized version of the model that is Lipschitz continuous. We mostly restrict our analysis to the Lipschitz continuous regularization. For regularized versions of the dissipative Maxwell-Bloch type model, we prove existence of solutions to the corresponding Cauchy problem. The core of the proof is based on results from compensated compactness due to P. Gérard and a Rellich type lemma. In parts, this proof closely follows the lines of an earlier work due to J.-L. Joly, G. Métivier and J. Rauch.

Video frame rate up-conversion is an important issue for multimedia systems in achieving better video quality and motion portrayal. Motion-compensated methods offer better quality interpolated frames since the interpolation is performed along the motion trajectory. In addition, computational complexity, regularity, and memory bandwidth are important for a real-time implementation. Motion-compensated frame rate up-conversion (MC-FRC) is composed of two main parts: motion estimation (ME) and motion-compensated frame interpolation (MCFI). Since ME is an essential part of MC-FRC, a new fast motion estimation (FME) algorithm capable of producing sub-sample motion vectors at low computational-complexity has been developed. Unlike existing FME algorithms, the developed algorithm considers the low complexity sub-sample accuracy in designing the search pattern for FME. The developed FME algorithm is designed in such a way that the block distortion measure (BDM) is modeled as a parametric surface in the vicinity of the integer-sample motion vector; this modeling enables low computational-complexity sub-sample motion estimation without pixel interpolation. MC-FRC needs more accurate motion trajectories for better video quality; hence, a novel true-motion estimation (TME) algorithm targeting to track the projected object motion has been developed for video processing applications, such as motion-compensated frame interpolation (MCFI), deinterlacing, and denoising. Developed TME algorithm considers not only the computational complexity and regularity but also memory bandwidth. TME is obtained by imposing implicit and explicit smoothness constraints on block matching algorithm (BMA). In addition, it employs a novel adaptive clustering algorithm to keep the low-complexity at reasonable levels yet enable exploiting more spatiotemporal neighbors. To produce better quality interpolated frames, dense motion field at the interpolation instants are obtained for both forward and backward motion vectors (MVs); then, bidirectional motion compensation using forward and backward MVs is applied by mixing both elegantly.

Thesis (PhD)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: The triple layer pillbox antenna is an antenna topology well suited for use as a stackable "plank" element in radar applications. Its suitability arises from the folding which makes it compact, and from the layered nature which can be exploited for low cost manufacture. Existing designs of these "cheese" antennas, whether two or three layers, suff er from two drawbacks: a) The bend or fold between layers introduces undesirable reflections and b) Due to their parabolic sector geometry virtually no pattern control is available to the designer. This work addresses both of these shortcomings. A low reflection transition is realized by introducing simple compensating elements into the design which, with minimal manufacturing complexity, off er high performance over a broad frequency and incidence angle range. To cater for pattern control the concept of "dual shaped reflectors" is borrowed from the high performance dish antenna literature and implemented in the pillbox geometry. This shaping off ers limited but useful control of the aperture distribution and thus indirectly over the radiation pattern. To test these innovations three X-band antennas have been designed, built and measured. An initial unshaped geometry is used for the fi rst design to show the fold or bend performance. This antenna has a simulated and measured 2GHz usable bandwidth, with a reflection coeffi cient below -10dB and side-lobes below -27dB over a bandwidth in excess of 20%. Shaping is then added to show how either side-lobe levels can be lowered to below -32dB, or the gain enhanced by 2dB. The enhanced designs have been built and experimentally veri fied. / AFRIKAANSE OPSOMMING: Die drie-dubbel gevoude pildoos antenna is `n antenna topologie wat goed gepas is vir die gebruik as `n stapelbare "plank" element vir radar aanwending. Sy geskiktheid kom vanwee die vou van die struktuur wat dit meer kompak maak sowel as die konstruksie moontlik goedkoper maak. Huidige ontwerpe van die antenna strukture, hetsy twee of drie lae, ly aan twee tekortkominge: a) Die buiging of vou tussen die lae veroorsaak ongewensde weerkaatsings en b) Weens hul paraboliese meetkunde is feitlik geen beheer oor die stralings patroon beskikbaar nie. Hierdie werk spreek beide hierdie tekortkominge aan. `n Lae weerkaatsing by die oorgang is verkry deur eenvoudige kompenserende elemente by die ontwerp in te voeg wat, met minimale vervaardigings kompleksiteit, hoë werkverrigting lewer oor `n breë frekwensie en invals hoek spektrum. Om patroon beheer te voorsien is die konsep van "dubbele gevormende weerkaatsers" geleen vanaf die hoë verkverrigting skottel antenna literatuur en in die pildoos meetkunde ingestel. Hierdie vorming lewer beperkte dog nuttige beheer oor die openings verspreiding en dus indirek oor die stralings patroon. Om hierdie nuwighede te toets is drie X-band antennas ontwerp wat gebou en gemeet is. 'n Aanvanklike ongevormende meetkunde is gebruik vir die eerste ontwerp om die vou of buiging se werksverrigting te bewys. Hierdie antenna het `n gesimuleerde en gemete 2GHz bruikbare bandwydte met `n weerkaatsings kwosiënt onder -10dB en sylobbe van minder as -27dB oor `n bandwydte van meer as 20%. Vorming is dan bygevoeg om te bewys dat of verlaagde sylobbe van onder -32dB of verhoogde aanwins met 2dB verkrygbaar is. Die verbeterde ontwerpe is gebou en eksperimenteel bewys.

<p>Recent algorithms for video coding achieve a high-quality transmission at moderate bit rates. On the other hand, those coders are very sensitive to transmission errors. Many research projects focus on methods to conceal such errors in the decoded video sequence. </p><p>Motion compensated prediction is commonly used in video coding to achieve a high compression ratio. This thesis proposes an algorithm which uses the motion compensated prediction of a given video coder to predict a sequence of several complete frames, based on the last correctly decoded images, during a transmission interruption. The proposed algorithm is evaluated on a video coder which uses a dense motion field for motion compensation. </p><p>A drawback of predicting lost fields is the perceived discontinuity when the decoder switches back from the prediction to a normal mode of operation. Various approaches to reduce this discontinuity are investigated.</p>

Recent algorithms for video coding achieve a high-quality transmission at moderate bit rates. On the other hand, those coders are very sensitive to transmission errors. Many research projects focus on methods to conceal such errors in the decoded video sequence. Motion compensated prediction is commonly used in video coding to achieve a high compression ratio. This thesis proposes an algorithm which uses the motion compensated prediction of a given video coder to predict a sequence of several complete frames, based on the last correctly decoded images, during a transmission interruption. The proposed algorithm is evaluated on a video coder which uses a dense motion field for motion compensation. A drawback of predicting lost fields is the perceived discontinuity when the decoder switches back from the prediction to a normal mode of operation. Various approaches to reduce this discontinuity are investigated.