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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
251

The dynamics of soliton interaction

Campbell, Fiona Mary January 2001 (has links)
No description available.
252

Professional counsellors’ personal narratives of "doing life" while "doing work"

Mikolayenko, Rhonda Delia 11 September 2014 (has links)
What does it mean to be a counsellor? What challenges do counsellors face? How do life events influence the personal and professional self of the counsellor? What insights are provided by time and experience that accompany a lifelong career? The purpose of this phenomenological qualitative study was to learn from six counsellors, each veteran in their careers, how critical life events influenced who they became as both a person and professional. Interview conversations presented retrospective narratives and personal stories illuminating whether each came to discover and develop an integrated self. Descriptive field notes, researcher reflections and comments further substantiated the complex world of counsellors. The interview data offered through this study exposed the intersection of the person and the professional as well as the valuable and diverse growth experiences that occurred along their career trajectories. Embedded in the interviews were implications for resiliency and sustainability; these were derived from learning that occurred with extensive time and experience.
253

A rhetorical analysis of the current challenges to the evolutionary paradigm

Yanos, Susan B. January 1990 (has links)
This study explores the establishment of the paradigm of evolution by means of natural selection, asserting that Darwin's theories were not scientifically revolutionary because he established rather than overthrew the existing paradigm in biology. Actually Darwin made three more important contributions than the theory of natural selection. He delivered a blow to essentialism, changing the universe from a product into a process. He established the hypothetico-deductive model of the physical sciences for natural history. And he demonstrated that teleological problems could be studied by scientists. The recent controversies in biology are continuations of the old debate over whether evolution is orderly or irregular, controlled by external or internal forces, continuous or discontinuous. The controversies can be separated into four separate challenges to neo-Darwinism: empirical, epistemological, methodological, and teleological. The study concludes that the empirical and teleological challenges do not pose serious threats to the existing paradigm, but unless the epistemological and methodological challenges can be met satisfactorily, the paradigm may be overthrown.This study also explores the differences between the rhetorical and scientific methods of inquiry. Modern science is considered as predominantly empirical, progressing because of the scientists' system of shared, rational values. Actually both metaphysician and physician ponder the same questions, embrace truth with the same assumptions, and operate with the same epistemology. Science is puzzle solving. Rhetoric deals with ill-defined problems, while science turns ill-defined problems into well-defined ones. The danger in separating the scientific and rhetorical methods is that Western man is split into two irreconcilable points of view: the moral and the scientific. The dichotomy arose because of the two fountainheads of Western culture. Plato "solved" the dichotomy by proposing two worlds of Becoming and Ideas. Darwin's solution depends on a different metaphysical pathos which is only now being realized, due to the rethinking of the paradigm as a result of the challenges. Rather than giving us two worlds, Darwin separated the forces of one, completely naturalistic world into a two-step process: chance and necessity. The problem is that many thinkers focus on only one of the processes, sometimes to the exclusion of the other. / Department of English
254

Application infrastructure evolution: An industrial case study

Csaky, Marcus 25 April 2013 (has links)
Modern computer infrastructure continues to advance at an accelerating pace. This advancement affects all aspects of computing systems such as hardware, device types, operating systems, and software. The constant change creates a problem for software vendors who must support not only the latest systems, but also previous versions. This infrastructure updating requirement limits software vendors when implementing new software features and in turn product innovation. There is a significant and increasing cost associated with adhering to application infrastructure requirement changes. To accommodate infrastructure change requirements, immediate and measurable action must be taken. First, the current industrial software development practices and tooling need to be analyzed. Current industrial release patterns and product update tooling must be understood and their shortcomings investigated. Next, key use cases ought to be identified and new methodologies and extensions to existing frameworks ought to be proposed to circumvent these difficulties. Finally, systems must be architected and developed to test the solution hypotheses and then deployed in commercial applications. This thesis focuses on these critical steps in the call to action to change software infrastructure management. In this thesis, we analyze an industrial problem including a real case study. We illustrate the currently available approaches and then describe how they are not sufficient in solving the problem. Our approach is based on an extension of a previously developed framework (i.e., the SmartContext commerce framework). In particular, we design an architecture and implementation for our industrial problem domain. / Graduate / 0984
255

Palm pollen and the fossil record

Harley, Madeline Margaret January 1996 (has links)
Previously published descriptions of the pollen morphology of the Palmae are reviewed and discussed. The earliest macro fossil records for palms are summarised, while a more detailed review is given of the fossil records of palmlike pollen. Selected literature relating to pollen sharing some similarities to palm pollen in other monocotyledonous families are briefly reviewed, and the fossil pollen records for these families are examined. A brief chronological account of earlier systematic treatments of the palms is provided, as well as an outline of the systematic treatment of the family used in the present account. The pollen morphology of 1150 collections, representing 765 species of palms,f rom all but seveno f the currentlyr ecognisedg enera,h asb eene xamýined, as well as dispersedp alm-likef ossil pollen from the middle Eoceneo f the Isle of Wight, and of Java. Iii silit pollen of fossil palm flowers from the Messel oil shales (Germany)a re describedP. ost meiotic tetrad stageh asb eens tudiedf or representatives peciesin all subfamiliese xceptingt he PhytelephantoideaeP.o llen morphologyo f both recenta nd fossil pollen is describedf rom light, scanning electrona nd, selectivelyf rom transmissione lectronm icroscopy,w hile tetrad resultsa re from light and scanninge lectronm icroscopy.F ull detailso f preparation methods,t erminologya nd databaseus sedf or pollen morphological,f ossil and tetrad studies are given. Seventeena perturet ypes,p lus numerouss ubtypesa, nd twelve exine types with numerous subtypes are identified. The aperture types are shown to be broadly separablein to two groupsw hich are associatedw ith either simultaneous (tetrahedralt etrads)o r successive(t etragonalt etrads)m icros porogenessi. In generalt heset wo groups supportp resents ystematico pinion regardingt he subfamilies.S uccessivem eiosisi s dominanti n subfamiliesC alamoideaea nd Nypoideaew hile, with somer are exceptionss, imultaneousm eiosisp redominates in the remainingf our subfamiliesC: oryphoideaeC, eroxyloideaeA, recoideaea nd PhytelephantoideaeP.o llenu ltrastructurei s treatedi n detail only for simple tectate exines where it is important for further definition. Six types and a number of subtypesa re described.T he systematicd istributionso f aperturea nd exine types are summarisedA. trend towardsl arger pollen is noted, with the smallest pollen occurring in the least specialised subfamily, the Coryphoideae, while very large-sized pollen are characteristic of subfamily Phytelephantoideae. Monosulcate, disulcate and zonosulcate pollen are described from fossil material and closest affinities with recent palms suggested. Pollen morphology of recent palms is summarised and discussed, and compared with pollen of selected monocotyledonous families. The bearing of pollen data on recent palm systematics is considered at various levels from subfamily to species. Angiosperm pollen evolution is re-considered and evolutionary pathways for palm pollen aperture types and exine types are suggested. In the light of recent pollen morphology for the family the fossil record of palm pollen is re-evaluated. Some widely accepted affinities are challenged while previously unconsidered affinities are suggested, particularly for the mid- Cretaceous. The need is emphasized for future fossil pollen studies to look critically for pre Late Cretaceous palm-like monosulcates, which would be more informative of the early history of the family than the apparently highly evolved, easily recognisable Spini. -onocolpiles of the Late Cretaceous. Palaeogeography, environment and distribution of fossil records and depositional environment are discussed. Probable evolutionary pathways of pollen morphology, including pollen tetrad data which suggests imultaneousra thert han successivem eiosisa s the plesiomorphics tate,o ffer further evidencet hat the palmsa re indeeda n ancient group, and support the hypothesis that the palms may have originated in South America and Africa (West Gondwana)in the Late Jurassic or early Cretaceous, prior to the complete separation of these continents.
256

A study of early-type close binaries

Bell, Steven A. January 1987 (has links)
It has become increasingly clear that many binary systems will pass through a common envelope stage at some point during their evolution. For short period systems composed of main-sequence 0 and early B stars this stage will probably occur for the first time towards the end of hydrogen-core burning in the primary component (case A evolution) rather than during the transition to the giant stage (case B evolution). If masses, radii, luminosities, temperatures and orbital parameters were well determined for a good sample of those systems, it could be established whether the individual components were so close that case A evolution was inevitable or whether the primary component had enough room to complete its main-sequence phase before reaching its Roche. limit and hence case B evolution. The latter mode has been studied extensively (both conservatively and non-conservatively) whereas the reception of matter by the secondary component in the rapid mass-transfer phase of case A evolution has only very recently been investigated. It is still one of the principal problems impeding further progress on this scenario. To resolve this situation and provide observational material with which to compare these theoretical models, an observing program was established to study systems of spectral type earlier than B5 and of orbital period of less than 1.8 in both the Northern and Southern Hemispheres. Light curves were obtained at St Andrews using the newly-refurbished Twin Photometric Telescope and analysed using software developed specifically for this instrument. Further spectroscopic and photometric data were obtained at La Palma SAAO, Sierra Nevada and Boyden. Analyses of these spectroscopic and photometric observations have provided the necessary physical parameters to determine the evolutionary status of these systems. The systems observed were AH Cephei and V1182 Aquilae which are shown to be detached systems, TT Aurigae, SX Aurigae and AI Crucis which are all semi-detached systems and V701 Scorpii and HZ Pyxidis which are contact systems. Accurately-determined parameters of 14 stars have been found, including four 0 stars in detached systems. Therefore-the number of stars with well-determined masses of greater than 30M has been increased by 25%. It is clear from this study that case A mass transfer will play and has played an important role in the evolution of five out of the seven systems. It is debatable whether or not the contact systems have passed through a mass transfer phase, particularly RZ Pyx. The evolutionary history of this system is of particular interest, especially if this binary was in a marginal contact configuration when it arrived on the main sequence. Attempts have been made to look for intrinsic variability in these systems but no periodic variation has been found in any of them. If such a phenomenon exists in one of the components of the binaries in the sample then it must have an amplitude of less than 0.01. The comparison of the physical parameters of 67 stars compiled by the author from this work and from published data with theoretical zero-age and terminal-age main sequences shows that traditional modelling of semi-convection without mass loss is not adequate. Convective overshooting and mass loss play a very important role in the evolution of massive close binary systems of short period.
257

The formation and evolution of elliptical galaxies

Brown, Richard Joseph Norman January 2003 (has links)
No description available.
258

Evolutionary ecology of bird-parasite associations

Tompkins, Daniel Michael January 1996 (has links)
This thesis investigates the ecological determinants of chewing louse (Insecta: Phthiraptera) host-specificity on four species of Malaysian swiftlets (Aves: Apodidae). Influences of host coloniality on louse ecology were also demonstrated, illustrating the dependence which these permanent ectoparasites have on their hosts. Louse collections were made to look for incidences of host-specific lice occurring on the "wrong" host ("straggling"). Straggling was observed, implying that lice disperse among host species. Thus, opportunity for louse dispersal (or lack thereof) does not govern the host-specificity of chewing lice on swiftlets. Experimental transfers of lice between hosts were conducted. Louse survival was reduced on foreign host species. This implies adaptation to specific host characters, suggesting that specialisation governs chewing louse host-specificity on swiftlets. There was no evidence for reciprocal adaptation of swiftlets to their normal louse species. Lice had no impact on the fitness of either swiftlets or the related common swift. Furthermore, neither swiftlet nor swift lice were transmitting pathogenic endoparasites. This implies that chewing lice and Malaysian swiftlets have not "coevolved". Survival of transferred lice was determined by the relatedness of donor and recipient hosts. Closer related swiftlet species are more similar in body size and feather dimensions. When the feather dimensions of the microhabitat distributions of the same louse species on different hosts were compared the results suggested that lice keep the dimensions of barb and barbule diameter, at which they occur, "constant" through microhabitat shifts. This suggests that feather dimensions are the host characters which determine the survival (and host-specificity) of chewing lice on birds. The ability of chewing lice to survive on hosts with similar feather morphology implies that "host-switching", between distantly related hosts with similar morphological characters (due to parallel or convergent host evolution), may have been an important factor in the evolution of bird-louse associations.
259

The evolution of traditional theatre and the development of modern theatre in Iran

Emami, I. January 1987 (has links)
No description available.
260

Optical polarimetry of star forming regions

Gledhill, Timothy Michael January 1987 (has links)
No description available.

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