This thesis deals with study of dynamics of the swirling flow. The swirling flow occurs frequently in hydraulic machinery (e.g., vortex rope in draft tube of the hydraulic turbine) and often influences operation of these machines. For this reason, sufficient knowledge regarding this characteristic flow is necessary for subsequent improvement of hydraulic machines. The theoretical part of this thesis contains description of flow instabilities and their manifestations, notably Kármán vortex street and vortex rope. In the next part, two methods are applied to these two transient flows in order to identify their specific dynamic properties. The first method, Fourier transform, enables to find frequencies of transient flow. The second method, proper orthogonal decomposition (POD), enables to identify planar or spatial eigenmodes of a specific swirling flow. Proper orthogonal decomposition is used in this thesis to identify planar eigenmodes of Kármán vortex street and spatial eigenmodes of vortex rope.

La machine à réluctance variable peut être utilisée dans les véhicules électriques où pour des considérations d’autonomie, le rendement est crucial. En raison du fort champ de fuite dans la région de l’entrefer de la machine à réluctance variable due à sa géométrie particulière à pôles saillants, les pertes « cuivre » peuvent devenir conséquentes. Il est alors recommandé de ne pas placer les conducteurs au voisinage de l’entrefer. Cependant, des instructions concrètes pour la conception d’un enroulement optimal sont manquantes. Généralement, les pertes « cuivre » dans les machines électriques sont la somme des pertes Ohm DC classiques et des pertes additionnelles dites par courants de Foucault. Les pertes DC étant constantes à un point de fonctionnement donné, l’optimisation est axée alors sur la réduction des pertes par courants de Foucault en jouant sur la configuration géométrique de l’enroulement. Dans le cas de calculs répétitifs fastidieux, rencontrés par exemple lors des processus de conception et d’optimisation du bobinage des machines électriques, il y a un intérêt significatif à réduire le temps de calcul. Dans ce travail, on présente trois techniques de réduction du modèle et leurs applications dans les analyses par la méthode des éléments finis. Outre l’influence de la fréquence d’alimentation et de la section du conducteur, plusieurs facteurs liés à la configuration de l’enroulement influent sur les pertes additionnelles par courants de Foucault :i) la position du conducteur dans l’encoche au voisinage de la dent du stator ou de la zone de l’entrefer .ii) la disposition des conducteurs envers les lignes du champ magnétique bidimensionnelles de l’encoche .iii) l’utilisation d’un conducteur massif ou multi filamentaire; les filaments sont connectés en parallèle et peuvent permuter leurs positions périodiquement au sein du conducteur tout au long du bobinage. Dans cette thèse, on étudie principalement l’influence de la disposition géométrique des spires dans l’encoche et du type du conducteur utilisé s’il s’agit d’un conducteur massif, en fils de Litz ou en fils torsadés. Les pertes par courants de Foucault sont la conséquence d’un couplage fort électrique-magnétique entre la densité du courant et la variation en fonction du temps du champ magnétique. En utilisant le modèle de Maxwell, ce couplage est décrit par une équation différentielle à dérivée partielle qui ne peut être résolue simplement. La résolution de cette équation utilisant l’approche analytique n’est possible que sous certaines hypothèses simplificatrices qui peuvent dégrader la fiabilité de la solution. La modélisation par la méthode des éléments finis permet quant à elle de prendre en compte le mouvement du rotor et la non-linéarité du circuit magnétique garantissant ainsi une meilleure précision. Néanmoins, cela conduit à une large capacité de stockage et à un temps de calcul substantiel qui peut entraver tout processus de conception ou d’optimisation. Pour surmonter ce problème, on propose dans ce manuscrit trois techniques de réduction du modèle. Ces techniques assurent une réduction efficace de la taille du système matriciel associé à la modélisation par la méthode des éléments finis et diminuent par conséquent le temps de calcul : i) une réduction spatiale qui évite une modélisation en 3D des conducteurs complexes en fils torsadés et en fils de Litz et propose une modélisation 2D satisfaisante .ii) la technique de la perturbation. iii) la réduction de l’ordre du modèle utilisant la méthode de la décomposition orthogonale aux valeurs propres combinée à la méthode d’interpolation empirique discrète. La comparaison du modèle réduit à un modèle complet de référence montre l’efficacité de la réduction du modèle à réduire le temps de calcul tout en restant en deçà d’une erreur de précision acceptable. / The switched reluctance machine can be used in hybrid or electric vehicle where, for autonomy considerations, energy efficiency is crucial. Because of the strong stray field in the air-gap region of the switched reluctance machine due to its salient pole geometry, the copper losses can become substantial. It is firmly recommended therefore not to place the coil conductors near the air-gap region. Nevertheless, concrete instructions for optimal winding design are missing. The copper losses in electrical machines are subdivided into classical DC ohmic losses and additional eddy current losses occurring due to the time varying magnetic fields penetrating the copper conductors. Based on the fact that the DC losses are constant at a given operating point, the optimization is focused on reducing the eddy current losses by modifying the winding geometry configuration. In the case of tedious repetitive calculations, met for example during design and optimization processes of electrical machine windings, there is a significant interest in reducing the computation time. This work suggests three model reduction techniques and their applications in the finite element analyses.Besides the frequency of the excitation current and the cross section of the coil conductors, several factors related to the winding configuration can affect the addition al eddy current losses:i) the coil conductor position in the winding slot especially near the stator pole or close to the air gapii) the disposition of the coil conductor against the two-dimensional flux lines in the slot windingiii) the subdivision of the solid conductor into multiple parallel strands swapping their positions periodically in the conductor cross section throughout the length of the machine winding.This thesis mainly studies the influence of the geometric coils disposition in the slot windings and the type of the conductor used whether it is solid or stranded, with Litz or twisted wires.The eddy current losses exit through the strong electro-magnetic coupling between the electric current density and the time dependent magnetic flux lines penetrating the conductors; it is described mathematically by a partial differential equation that cannot be solved easily. The analytical approach, which is used practically for a quick resolution of the strong electro-magnetic coupling equation, is only possible under certain simplifying assumptions that deteriorate brutally the reliability of the copper losses calculation. The finite element modeling as for it, allows taking into account the rotor motion and the non-linear behavior of the magnetic circuit, thus ensuring a higher accuracy. However, it leads under these conditions to a substantial calculation time and requires large storage capacity. These constraints are critical and may hinder therefore any process of conception or optimization. In this thesis, we suggest three different model reduction techniques that can be effective in reducing the size of large scale complete finite element models and enable therefore to shorten the computational time:i) the spatial reduction avoiding the 3D modeling which seems required in the case of twisted and Litz wires and suggesting an alternative satisfactory 2D modeling.ii) the perturbation technique.iii) the model order reduction using the proper orthogonal decomposition combined with the discrete empirical interpolation method.The comparison between the reduced model solutions to that of the complete finite element model has proved the effectiveness of the proposed model reduction techniques; they allow shrinking the required computational time while staying below an acceptable error of accuracy.

Obesity and the number overweight of children are currently major global issues. According to the Regional Office for Europe (2006) obesity has risen three times over the last two decades worldwide. The attention is currently focused on health promotion and disease prevention among the population through comprehensive health education starting in the early age of individuals, aimed to slow down the increasing incidence of obesity and related health issues. This thesis discusses the pedagogical aspects of health, specifically the options on how to shape nutritional habits of elementary and middle school students and how to systematically deepen the required knowledge about healthy nutrition by implementation of nutrition education programs. The purpose of this study was to determine the relationships between dietary habits and healthy nutrition knowledge of grade nine students in elementary schools from the South Bohemian region in Czech Republic. A validated Nutritional survey and Nutritional knowledge quiz were designed to determine the relationship between knowledge and behavior of grade nine students from South Bohemia elementary schools. The validity of the Nutritional survey and the Nutritional knowledge quiz were tested using analytical analysis of all survey and test items and examining...

Efficient analysis and storage of data is an integral but often challenging task when working with computation fluid dynamics mainly due to the amount of data it can output. Methods centered around the proper orthogonal decomposition were used to analyze, compress, and model various simulation cases. Two different high-fidelity, time-accurate turbomachinery simulations were investigated to show various applications of the analysis techniques. The first turbomachinery example was used to illustrate the extraction of turbulent coherent structures such as traversing shocks, vortex shedding, and wake variation from deswirler and rotor blade passages. Using only the most dominant modes, flow fields were reconstructed and analyzed for error. The reconstructions reproduced the general dynamics within the flow well, but failed to fully resolve shock fronts and smaller vortices. By decomposing the domain into smaller, independent pieces, reconstruction error was reduced by up to 63 percent. A new method of data compression that combined an image compression algorithm and the proper orthogonal decomposition was used to store the reconstructions of the flow field, increasing data compression ratios by a factor of 40.The second turbomachinery simulation studied was a three-stage fan with inlet total pressure distortion. Both the snapshot and repeating geometry methods were used to characterize structures of static pressure fluctuation within the blade passages of the third rotor blade row. Modal coefficients filtered by frequencies relating to the inlet distortion pattern were used to produce reconstructions of the pressure field solely dependent on the inlet boundary condition. A hybrid proper orthogonal decomposition method was proposed to limit burdens on computational resources while providing high temporal resolution analysis.Parametric reduced order models were created from large databases of transient and steady conjugate heat transfer and airfoil simulations. Performance of the models were found to depend heavily on the range of the parameters varied as well as the number of simulations used to traverse that range. The heat transfer models gave excellent predictions for temperature profiles in heated solids for ambitious parameter ranges. Model development for the airfoil case showed that accuracy was highly dependent on modal truncation. The flow fields were predicted very well, especially outside the boundary layer region of the flow.

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Bats are some of the most agile flyers in nature. Their wings are highly articulated which affords them very fine control over shape and form. This thesis investigates the flight of Hipposideros Pratti. The flight pattern studied is nominally level and straight. Measured wing kinematics are used to describe the wing motion. It is shown that Proper Orthogonal Decomposition (POD) can be used to effectively to filter the measured kinematics to eliminate outliers which usually manifest as low energy higher POD modes, but which can impact the stability of aerodynamic simulations. Through aerodynamic simulations it is established that the first two modes from the POD analysis recover 62% of the lift, and reflect a drag force instead of thrust, whereas the first three modes recover 77% of the thrust and even more lift than the native kinematics. This demonstrates that mode 2, which features a combination of spanwise twisting (pitching) and chordwise cambering, is critical for the generation of lift, and more so for thrust. Based on these inferences, it is concluded that the first 7 modes are sufficient to represent the full native kinematics. The aerodynamic simulations are conducted using the immersed boundary method on 128 processors. They utilize a grid of 31 million cells and the bat wing is represented by about 50000 surface elements. The movement of the immersed wing surface is defined by piecewise cubic splines that describe the time evolution of each control point on the wing. The major contribution of this work is the decomposition of the native kinematics into canonical flapping wing physical descriptors comprising of the flapping motion, stroke-plane deviation, pitching motion, chordwise, and spanwise cambering. It is shown that the pitching mode harvests a Leading Edge Vortex (LEV) during the upstroke to produce thrust. It also stabilizes the LEV during downstroke, as a result, larger lift and thrust production is observed. Chordwise cambering mode allows the LEV to glide over and cover a large portion of the wing thus contributing to more lift while the spanwise cambering mode mitigates the intensification of LEV during the upstroke by relative rotation of outer part of the wing ( hand wing ) with respect to the inner part of the wing ( arm wing). While this thesis concerns itself with near straight-level flight, the proposed decomposition can be applied to any complex flight maneuver and provide a basis for unified comparison not only over different bat flight regimes but also across other flying insects and birds. / MS / Bats are some of the most agile flyers in nature. Their wings are highly articulated which affords them very fine control over shape and form. This thesis investigates the flight of Hipposideros Pratti. The flight pattern studied is nominally level and straight. Measured wing kinematics are used to describe the wing motion. The central motivation of the thesis is to characterize how the bat uses its wings to generate lift to counter gravity and thrust to move forward against drag forces. A mathematical filter based on Proper Orthogonal Decomposition (POD) is used to filter the measured wing motion to eliminate high frequency noise in the data but at the same time including including the important motions which produce lift and thrust. The filtered native kinematics is decomposed into flapping wing motions comprising of flapping mode, stroke-plane deviation, pitching motion, chordwise, and spanwise cambering. It is shown that the pitching mode harvests the low pressure region created by the Leading Edge Vortex (LEV) during the upstroke to produce thrust. It also stabilizes the LEV during the downstroke, as a result, larger lift and thrust production is observed. Chordwise cambering mode allows the LEV to glide over and cover a large portion of the wing thus contributing to more lift, while the spanwise cambering mode mitigates the intensification of LEV during the upstroke by relative rotation of the outer part of the wing (hand wing) with respect to the inner part of the wing (arm wing). While this thesis concerns itself with near straight-level flight, the proposed decomposition can be applied to any complex flight maneuver and provide a basis for unified comparison not only over different bat flight regimes but also across other flying insects and birds.

OPSOMMING Alhoewel die trustfiguur reeds sedert die 19e Eeu in Suid-Afrika erken word, en as `n suiwer trustfiguur tipeer kan word, is die hantering van die regte van sekere trustbegunstigdes steeds in onsekerheid gehul. Die hoofrede hiervoor is die oorbeklemtoning van die wyse waarop trusts tot stand kom en die onderbeklemtoning van die unieke fidusiêre aard van die trust na oprigting daarvan. In Engeland, Skotland, Sri Lanka, Louisiana en Quebec, waar die suiwer trustfiguur ook aanwending vind, bestaan, in teenstelling met die oënskynlike regsposisie in Suid-Afrika, die moontlikheid van trustbegunstigdes sonder regte glad nie. In hierdie jurisdiksies speel die oprigtingsinstrument `n ondergeskikte rol en ontstaan die regte van trustbegunstigdes ex lege uit hoofde van die trustfiguur as `n vertrouensverhouding sui generis. Alhoewel die Suid-Afrikaanse trustreg die fidusiêre aard van die verhouding tussen trustee en trustbegunstigde erken, word die aard en omvang van die regte wat hieruit voort behoort te vloei nog nie voldoende deur die howe erken nie. Vertrouensverhoudinge waaruit regte en verpligtinge ex lege voortspruit, is bekend aan die gemenereg en word steeds hedendaags aangetref in verskeie ander vakdissiplines binne die Suid-Afrikaanse reg, waaronder die maatskappyereg. Die suiwer trustfiguur stel verder noodwendig `n vertrouensverhouding daar wat juis daarop gemik is om die regte van trustbegunstigdes te beskerm. Die standpunt word dus ingeneem dat alle trustbegunstigdes in Suid-Afrika derhalwe oor ex lege regte beskik. Daar word aan die hand gedoen dat trustbegunstigdes se regte nie uitsluitlik voortvloei uit hoofde van die tersaaklike oprigtingshandeling nie, maar dat unieke regte ontstaan as gevolg van die onderliggende fidusiêre verhouding wat tot stand kom wanneer, maar ongeag hoe, die trust opgerig word. Kortom: Die fidusiêre verhouding behoort erken te word as eie, onafhanklike bron van trustbegunstigdes se moontlike regte teen die trustee in die geval van trustbreuk. Nie net is dit `n logiese stap in die ontwikkeling van die gemenereg nie, maar sal dit ook die beskerming van trustbegunstigdes in die Suid-Afrikaanse trustreg op dieselfde voet plaas as trustbegunstigdes in die ander jurisdiksies wat nagevors is. So 'n stap sal bydra tot regsekerheid en nie tot `n wesentlike omwenteling in die Suid-Afrikaanse trustreg en -administrasie lei nie. SYNOPSIS Although the trust figure has been recognised in South Africa since the 19th century and can be characterised as a proper trust, uncertainty still prevails regarding the scope and acknowledgement of the rights of some trust beneficiaries. The main reason for this is the over-emphasis of the manner in which trusts are created, and the under-emphasis of the unique fiduciary nature of the trust once it has been established. In England, Scotland, Sri Lanka, Louisiana and Quebec where the proper trust figure is also applied, there is no possibility, contrary to the apparent legal position in South Africa, of trust beneficiaries without rights. In these jurisdictions the instrument used to create a trust plays a subordinate role and the rights of trust beneficiaries originate ex lege by virtue of the trust itself as a relationship of trust sui generis. Although South African trust law acknowledges the fiduciary nature of the relationship between trustee and trust beneficiary, the nature and extent of the rights that should emanate from this relationship are not adequately acknowledged by the courts. / Jurisprudence / L.L.D.

Summaries in English and Afrikaans / Daar is gepoog om 'n omvattende, algemeen geldige maatstaf te vind waarmee enige opvoeding vir outentisiteit geevalueer kan word. Die moontlikheid dat die "essensiestruktuur van behoorlike volwassenewees en van opvoedingsdoel" (ES) hieraan voldoen, is ondersoek. Die genoemde essensiestruktuur (ES) is in 'n modeldiagram CESM) saamgevat. Dit bevat die volgende essensies: 'religiositeit', die 'etiese', 'affektiwiteit', 'liggaamlikheid'. 'nasionaliteit' (insluitende 'kulturaliteit'. 'historisiteit' en die 'politiese'), die 'estetiese'. 'individualiteit'. 'sosialiteit'. die 'ekonomiese'. 'vryheid'. 'gesag'. 'taal' en 'redelikheid'. asook die sewe normbeelde wat 'n substruktuur van die 'etiese' is. 'Religiositeit' is hierargies die mees belangrikste essensie. gevolg deur die 'etiese'. Aldie ander essensies verkeer op 'n derde niveau van belangrikheid. Om outentiek te wees behoort 'n opvoedingseksemplaar aan boge noemde hierargie te voldoen. Elk van die genoemde essensies is verduidelik, asook hulle samehangende verbandhoudendheid binne die ESM. Die harmonie binne hierdie gestruktureerdheid is van deurslaggewende belang vir die begryping van outentisiteit by opvoeding. 'n Evalueringsmetode. bekend as ''essensiestruktuur-analise" (ES-analise). is uit bogenoemde deur die navorser ontwikkel. 'n Uiteensetting van mikro-. meso- en makro ES-analise is oak verstrek. Beskrywings van eksemplare van opvoeding en van aanverwante opvoedingsaangeleenthede word in die lig van die ESM geanaliseer. Hoe meer 'n opvoedingseksemplaar ooreenstem met die ESM hoe nader beweeg dit aan outentisiteit. en omgekeerd. Ter illustrasie van die toepassingsmoontlikhede van ES-analise is die mensbeskouing van C.K. Oberholzer. die kindbeskouing van J.C. Coetzee. die Christelike lewensopvatting, die wereldbeskouing van Albert Schweitzer en die opvoedingsleer van die Klassisisme aan ES-analises onderwerp. Die Christelike lewensopvatting kon as outentiek geevalueer word, terwyl die mensbeskouing van Oberholzer. die kindbeskouing van Coetzee en die wereld beskouing van Schweitzer naby aan outentisiteit beweeg. Die opvoedingsleer van die Klassisisme vertoon heelparty essensie-diskrepansies. Die hipotese, dat ES-analise 'n betroubare evalueringsmaatstaf vir outentieke opvoeding kan wees, is bevestig. Derhalwe kon die aanwending vanESanalise oar 'n wye spektrum aanbeveel word. byvoorbeeld by histories opvoedkundige eksemplare, godsdienslere. skoolstelsels en meegaande kurrikula en by die ontwikkeling van opvoedingsprogramme. Die huidige opvoeding en kon temporere leefwyse kan in die toekoms verbeter word indien ES-analise daadwerklik toegepas sou word. / An effort was made to find a universally valid criterion to evaluate any education for authenticity. The "essence-structure of proper adulthood and of education-aim" (ES) was investigated in this regard. This essence-structure (ES) was condensed in a model diagram (ESM). It includes the fo 11 owing essences: · re 1 i gi ousness · , the · ethi ca 1 ' , · affec tiveness'. 'bodiliness'. 'nationality' ('culturality'. 'historicity' and the 'political'), the 'aesthetical'. 'individuality', 'sociality·. the 'economical'. 'freedom·. 'authority'. 'language' and 'rationality'. as well as the seven norm images - a substructure of the 'ethical'. Hierarchically 'religiousness· is the most important essence. followed by the 'ethical·. All other essences exist on a third 1 eve 1 of importance. To qualify as authentic an exemplar of education ought to comply with the above-mentioned hierarchy. Each of the essences and their interrelatedness within the ESM were discussed. The harmonious co-existence within this structuredness is of paramount importance in understanding educational authenticity. Emanating from the above-mentioned an evaluation method. known as "essence structure-analysis" (ES analysis). was developed. Micro. meso and macro-ESanalysis were also explained. Descriptions of exemplars of education and of educationally related matters are analysed using the ESM as the criterion. The more an exemplar corresponds with the ESM. the more it re sembles authenticity, and vice versa. To demonstrate the application potential of ES analysis C.K. Oberholzer's view of man. J.C. Coetzee's view on childhood. the Christian life-view. Albert Schweitzer's world-view and the educational doctrine of the Classicism were subjected toES analyses. The Christian life-view could be evaluated as authentic. while Oberholzer's view of man. Coetzee's view on childhood and Schweitzer's world-view are resembling authenticity closely. The educational doctrine of the Classicism revealed several essence discre pancies. (viii) The hypothesis. that ES analysis can be a reliable evaluation criterion for authentic education. was confirmed. It could thus be recommended that ESanalysis be implemented over a broad spectrum. for example when studying historico-educational exemplars. doctrines of religion. school systems and curricula and assisting in developing educational programs. The contemporary education and way of life can be ameliorated in the future if ES analysis is applied actively. / Educational Studies / D.Ed. (Philosophy of Education)

Text in Afrikaans / In hierdie verhandeling word skoolname as onderafdeling van die Onomastiek behandel. Die gee van skoolname is 'n amptelike aangeleentheid en daarom is die beleid onderliggend aan die handeling onder die loep geneem. Beleid bepaal die ortografiese aard van skoolname en die manifestasie daarvan is sosiolinguisties van belang. Skoolname, wat onder eiename ressorteer, is hoofsaaklik oor 'n semantiese en sosiolinguistiese boeg gegooi, daarom word terme soos verwysing, konvensie en agtergrondbeskrywing aan die hand van veral die teoriee van Devitt, Strawson en Kripke beskryf. Van Langendonck le veral klem op die pragmatiese aard van die eienaam en daarom vorm sy teorie, die hetekenisparadoks van die eienaam, 'n belangrike uitgangspunt by die konsepsuele en pragmatiese aard van skoolname. Die gee van name is In suiwer menslike handeling wat selde ooit ongemotiveer geskied. Die ontstaansmotiewe wat skoolnaamgewing ten grondslag le, word bespreek aan die hand van die verskillende kategoriee. Botsende sosiale faktore soos veral teweeggebring deur kulturele diversiteit beinvloed naamgewing en daarom verander name. Die faktore onderliggend aan naamsverandering word uitgelig en bespreek. Die moontlikheid om ten spyte van 'n multikulturele en multilinguistiese samelewing tog 'n nasionale identiteit te vertoon, word ten slotte ondersoek en bespreek. / In this dissertation, names of schools as a subdivision of Onomastics are dealt with. School names are researched mainly under the cloak of Semantics and Socio-linguistics. Therefore, terms like reference, convention and a backing of descriptions are referred to according to the theories of Devitt, Strawson and Kripke. Van Langendonck specifically emphasises the pragmatic nature of proper nouns in his theory the paradox of the meaning of proper nouns which is an important point of departure in the conceptual and pragmatic nature of the names of schools. The underlying motives in respect of school naming are categorized and discussed according to the motives of origin. Conflicting social factors play an important role in the naming of schools and therefore names also change. These changes are accentuated and discussed. The possibility for a country to reflect a national identity in spite of a multicultural and multilingual society, is explored and discussed. / Afrikaans & Theory of Literature / M.A. (Afrikaans)