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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.
631

A Marxist Reading Of Things Fall Apart In The Esl Classrom : Exploring Colonial Socio-economic Exploitation in the Nigerian Context

Nkalubo, Arthur E. January 2021 (has links)
This thesis aims to explore how a critical reading of the novel Things Fall Apart (1958) can provide valuable perspective for educators and students when examining socio-economic issues in  a colonial context in the ESL classroom. The main issues being analysed are how the novel reveals and explores socio-economic forms of exploitation under colonialism, and how a critical reading of the novel can be used in teaching to inform and persuade learners about social injustices. To show this, the essay examines the novel from a marxist perspective, and more specifically by drawing on the concept of primitive accumulation to understand and explain the changes brought about by the introduction of colonial rule. The changes in this context include the Igbo community's relation to land, its socio-economic and cultural aspects as well as the introduction of trade. The discussion and analysis of the novel centre on social injustices due to land expropriation, breakdown of traditional values and customs, and economic changes brought about by the arrival of Europeans in the context of colonialism. Expanding on this, the essay also reflects on the pedagogical implications of its arguments by showing how a critical reading of Things Fall Apart might provide an opportunity for teachers to underline issues of social injustice, material, and economic forms of exploitation under colonialism and beyond. This literary analysis also discusses and reflects on the practical challenges and possibilities of teaching such issues in the ESL classroom by using the concept of critical literacy.
632

Rozšíření funkcionality lokátoru pro poziční systém reálného času / New features for real-time positioning system locator

Studený, Jakub January 2019 (has links)
The diploma thesis deals with the detection of falls and impacts, based on data obtained from inertial sensors, and by measuring the distance using a laser. The aim of this thesis is to extend the functionality of locators from Sewio. The thesis describes the procedure for designing algorithms for detection of falls and impacts. Then there is a procedure for development of hardware and software solution, for laser distance measurement by locator, together with presentation of achieved measurement results realized by locator after implementation of proposed solution. The work also emphasizes the minimization of energy consumption of individual solutions. In conclusion, there is a discussion of achieved results with evaluation of efficiency and usability of proposed solutions.
633

Instabilités de trajectoires de sphères, ellipsoïdes et bulles / Path instabilities of spheres, spheroids and bubbles

Zhou, Wei 29 September 2016 (has links)
La thèse présente une étude numérique des instabilités de trajectoires de sphères, d'ellipsoïdes aplatis et de bulles en mouvement libre sous l'action de la gravité, de la poussée d'Archimède et des forces hydrodynamiques. Le chapitre sur les sphères reprend, complète et étend l'étude numérique de Jenny et al. (2004) en se concentrant sur la transition au chaos et sur les trajectoires chaotiques. Les résultats montrent la différence entre le scénario de transition au chaos de sphères de faible et de grand rapport de densité. Plusieurs grandeurs statistiques sont proposées afin de fournir une caractérisation quantitative des états chaotiques. Elle permettent de mettre en relation les états ordonnées et chaotiques et offrent une possibilité de comparaison objective de données aléatoires d'origine numérique ou expérimentale. L'étude, très extensive, du comportement d'ellipsoïdes aplatis établit le lien entre les disques et les sphères en faisant varier l'aplatissement des objets depuis infiniment plat jusqu'à presque sphérique. Les huit diagrammes d'état présentés permettent de comprendre l'effet de la forme des ellipsoïdes sur le scénario de transition. Le cas d'ellipsoïdes presque sphériques montre que de faibles imperfections de la forme peuvent avoir in impact significatif sur les trajectoires de sphères de très faible rapport de densité. Pour les bulles considérées dans la limite de rapport de densité et viscosité az/liquide nul, l'étude se concentre sur l'analyse de stabilité linéaire et aboutit à la courbe de stabilité marginale dans le plan des paramètres nombre de Bond – nombre de Galilée en tenant compte de la déformation des bulles au moment de la perte de leur axisymétrie. Plus deux décades de nombres de Bond, entre 0,1 et 20, sont couvertes. Les résultats montrent clairement l'effet de la déformation de la bulle sur le seuil de l'instabilité. / The thesis presents a numerical study of path instabilities for spheres, oblate spheroids and bubbles moving freely under the effect of the gravity, buoyancy and hydrodynamic forces. For spheres, the parametric study of Jenny et al. (2004) is revisited, improved end extended with a special focus on the chaotic states. The results reveal that the effect of density ratio responsible for different oblique oscillating states of low and high frequencies has a significant impact both on the onset of chaos and on the behavior of fully chaotic states. Several quantitative statistical quantities are proposed and shown to be relevant for establishing the relation between chaotic and ordered states and for an objective comparison of random data of numerical or experimental origin. The extensive study on freely moving spheroids establishes the link between disks and spheres by varying the aspect ratio of spheroids from infinitely flat to almost spherical. The state diagrams provided for eight different aspect ratios of spheroid show in detail how the transition scenario varies depending of the body shape. The investigation of almost spherical spheroids reveals the specificities of the dynamics of light imperfect spheres.For the deformable gas bubble in the limit of zero gas/liquid density and viscosity ratio, a marginal stability curve is given in the two-parameter plane of the Galileo and the Bond number indicating the critical Galileo numbers for the loss of stability of vertical trajectories. The numerical investigation covers more than two decades of Bond number going from 0.1 to 20. The results clearly show the crucial role of the surface deformation.
634

Exorcismus v Mk 5,1-20 a zlí duchové v židovských tradicích / Exorcism in Mark 5:1-20 and evil spirits in Jewish traditions

Ondra, Michal January 2017 (has links)
ONDRA, Michal. Exorcism in Mark 5:1-20 and evil spirits in Jewish traditions The goal of this master thesis is to introduce the readers to Jewish demonology, how it evolved, what influenced it, and how it was reflected in the works on the evangelists when they wrote down the stories of Jesus' confrontations with the forces of darkness. At first you will be introduced to the term "demon", which is followed by an excursion into the Hellenistic culture, the period of the Old and the New Testament and, of course, into the intertestamental literature. It is specifically the intertestamental literature which is the most relevant, since it is a very rich collection of works many of which contain references to demonology and angelology. In the second half of this thesis you will find an analysis of Mark's fifth chapter (Mk 5:1-20), which is subsequently compared to similar stories found in the gospel of Luke and Matthew. The final chapter of this thesis shortly reflects the influence of the Jewish tradition on the demonology of Mark's gospel.
635

Obnova československého woodcrafterského hnutí po roce 1989 / Restoration of the Czechoslovak woodcraft movement after 1989

Faů, Roman January 2018 (has links)
This master thesis maps out events and processes which are connected with the resurgence of the Woodcraft league of Czechoslovakia after the fall of communism in Czechoslovakia in 1989. It deals with woodcraft community and affiliated groups that intensified their activities during the last years of the period of normalization in Czechoslovakia. After the Velvet revolution, these groups and individuals represented basis for the resurgence of the Woodcraft league. Furthermore, this paper describes concrete steps connected with this resurgence, introduces prominent actors of this process and tries to explain their major steps. It does not omit controversial events, neither ideological cleavages linked to the resurgence of the organisation, which was gagged more than 40 years. Finally, this final thesis puts the focus on the evolution of the organisation during its first modern period when it has succeeded in establishing itself within the Czechoslovakian society marked by a newly gathered freedom, an uncritical euphoria and by the subsequent return to reality. The information for this study was collected using the method of oral history, more specifically through interviews with prominent actors of these events. Collected findings were subsequently compared with information from other written sources...
636

Reliability of life event assessments: test-retest reliability and fall-off effects of the Munich interview for the assessment of life events and conditions

Wittchen, Hans-Ulrich, Essau, Cecilia Ahmoi, Hecht, Heidemarie, Teder, Wolfgang, Pfister, Hildegard January 1989 (has links)
This paper presents the findings of two independent studies which examined the test-retest reliability and the fall-off effects of the Munich Life Event List (MEL). The MEL is a three-step interview procedure for assessing life incidents which focusses on recognition processes rather than free recall. In a reliability study, test–retest coefficients of the MEL, based on a sample of 42 subjects, were quite stable over a 6-week interval. Stability for severe incidents appeared to be higher than for the less severe ones. In the fall-off study, a total rate of 30% fall-off was noted for all incidents reported retrospectively over an 8-year period. A more detailed analysis revealed average monthly fall-off effects of 0.36%. The size of fall-off effects was higher for non-severe and positive incidents than for severe incidents. This was particularly evident for the symptomatic groups. Non-symptomatic males reported a higheroverall number of life incidents than females. This was partly due to more frequent reporting of severe incidents. The findings of the fall-off study do not support the common belief that the reliability oflife incident report is much worse when the assessment period is extended over a period of several years as compared to the traditional 6-month period.
637

Evaluating the Undrained Shear Strength of Sulphide-Bearing Soils in the Sundsvall Area / Utvärdering av den odränerade skjuvhållfastheten i sulfidhaltiga jordar i Sundsvallsområdet

Holm, Gustaf January 2022 (has links)
Sulphide soils in Sweden are mainly found along the northeast coastline. These soils area characterized by their fine grain size, low shear strength and black, or grey, color. These soils are also found further south, in the Sundsvall area in Västernorrland, but have slightly lower sulphide content there. They are therefore often classified as sulphide-bearing soils. It is presumed that the undrained shear strength is underestimated in these soils. The undrained shear strength is used in the design of different geotechnical reinforcements. To obtain the undrained shear strength of a soil, several methods can be used. In situ, cone penetration tests or field vane tests can be used for example. In a laboratory environment, the undrained shear strength can be obtained from fall cone test or direct shear tests on undisturbed samples. Depending on how the soil is classified, they can be evaluated as a sulphide soil or as inorganic clay.  The objective of this master's thesis is to investigate if there are any indications showing that the undrained shear strength of sulphide-bearing soils in the Sundsvall area is being underestimated. It has also been investigated whether these soils should be evaluated as inorganic fine-grained soils instead of sulphide soils. Attempts have also been made to find a more suitable and site-specific reduction factor, cone factor, for the cone penetration tests. In order to enable this study, data from the mentioned investigation methods have been collected from Sweco's project Dubbelspår Dingersjö-Sundsvall C. The Project was separated into three subareas, since there were mainly three areas with direct shear tests. The data was evaluated both as sulphide soil and as inorganic clay, and then compared with the reference values from the direct simple shear tests. The site-specific cone factors for the cone penetration tests were also derived by using the undrained shear strength from the direct simple shear tests.  The result from the comparison with the reference values shows that the undrained shear strength of the sulphide-bearing soils in the Sundsvall area is underestimated if it is evaluated as sulphide soil. This applies to all three methods, cone penetration tests, fall cone tests and field vane tests. The fact that the undrained shear strength is currently underestimated means that costs and environmental impact could be reduced in many projects in Västernorrland if a more accurate reduction were to be used. New cone factors were also derived as a part of the result. The new cone factors were 20.55, 18.84 and 17.04 for the three subareas. This can be compared to the current cone factor for sulphide soil, which is 20. At the end of this report it is discussed whether the direct simple shear tests are the most suitable method for obtaining reference values in these soils. It is also discussed which parameters are believed to affect the cone factors. Future research should investigate how the silt and organic content affects the undrained shear strength. This should be done to be able to find a more accurate reduction for sulphide-bearing soils. Whether the direct simple shear tests are best suited to use as a reference values should also be investigated further. / Sulfidjordar i Sverige återfinns främst längst den nordöstra kustlinjen. Dessa jordar är generellt sett finkorniga, har låg skjuvhållfasthet och är ofta svarta eller gråa. Sulphidjordar återfinns även längre söder ut, i Sundsvallsområdet i Västernorrland, men sulfidinnehållet är något lägre i det området. De klassas därför ofta som sulfidhaltiga. Det förmodas att den odränerade skjuvhållfastheten underskattas i dessa jordar. Den odränerade skjuvhållfastheten används när olika geotekniska lösningar ska dimensioneras. Det finns flera olika metoder som kan användas för att erhålla den odränerade skjuvhållfastheten. I fält kan till exempel CPT-sonderingar och vingförsök utföras. I en laboratoriemiljö kan den odränerade skjuvhållfastheten erhållas från fallkonförsök och direkta skjuvförsök på ostörda jordprover. Beroende på hur jordarten klassificeras kan de utvärderas som en sulfidjord eller oorganisk lera. Syftet med detta examensarbete är att undersöka om det finns indikationer som tyder på att den odränerade skjuvhållfastheten i sulfidhaltiga jordar i Sundsvallsområdet underskattas om de utvärderas som sulfidjord. Det har även undersökts om dessa jordar ska utvärderas som en oorganisk finkornig jord istället för en sulfidjord. Det har också gjorts försök att hitta mer passande och platsspecifika, reduktionsfaktorer, konfaktorer, för CPT-sondering. För att möjliggöra undersökningen har data från de nämnda undersökningsmetoderna sammanställts från projektet Dubbelspår Dingersjö-Sundsvall C. Projektet har delats upp i tre delområden, eftersom det främst finns tre områden där direkta skjuvförsök har utförts. Undersökningarna utvärderades både som sulfidjord och oorganisk lera och jämfördes sedan med referensvärden från de direkta skjuvförsöken. Även de platsspecifika konfaktorerna för CPT härleddes med hjälp av den odränerade skjuvhållfastheten från de direkta skjuvförsöken.  Resultaten från jämförelsen med referensvärdena visar att den odränerade skjuvhållfastheten i sulfidhaltiga jordar i Sundsvallsområdet underskattas när den utvärderas som sulfidjord. Detta gäller alla tre metoder, CPT, fallkonförsök och vingförsök. Faktumet att den odränerade skjuvhållfastheten underskattas innebär att kostnad och klimatpåverkan skulle kunna minska i många projekt i Västernorrland om en mer exakt reduktion skulle göras. Nya konfaktorer härleddes också som en del av resultatet. De nya konfaktorerna var 20.55, 18.84 och 17.04 i de tre delområdena. Det kan jämföras med den nuvarande konfaktorn för sulfidjord, som är 20. I slutet av rapporten diskuteras det huruvida direkta skjuvförsök är den bäst lämpade metoden för att ta fram referensvärden i dessa jordar. Det diskuteras även vilka parametrar som tros påverka konfaktorn. Framtida forskning borde undersöka hur siltinnehållet och det organiska innehållet påverkar den odränerade skjuvhållfastheten. Det borde göras för att kunna erhålla en mer lämplig reduktion för sulfidhaltiga jordar. Om direkta skjuvförsök är bäst lämpad att använda som referensvärde borde också undersökas vidare.
638

EXPLICIT BOUNDARY SOLUTIONS FOR ELLIPSOIDAL PARTICLE PACKING AND REACTION-DIFFUSION PROBLEMS

Huanyu Liao (12880844) 16 June 2022 (has links)
<p>Moving boundary problems such as solidification, crack propagation, multi-body contact or shape optimal design represent an important class of engineering problems. Common to these problems are one or more moving interfaces or boundaries. One of the main challenges associated with boundary evolution is the difficulty that arises when the topology of the geometry changes. Other geometric issues such as distance to the boundary, projected point on the boundary and intersection between surfaces are also important and need to be efficiently solved. In general, the present thesis is concerned with the geometric arrangement and behavioral analysis of evolving parametric boundaries immersed in a domain. </p> <p>The first problem addressed in this thesis is the packing of ellipsoidal fillers in a regular domain and to estimate their effective physical behavior. Particle packing problem arises when one generates simulated microstructures of particulate composites. Such particulate composites used as thermal interface materials (TIMs) motivates this work. The collision detection and distance calculation between ellipsoids is much more difficult than other regular shapes such as spheres or polyhedra.  While many existing methods address the spherical packing problems, few appear to achieve volume loading exceeding 60%. The packing of ellipsoidal particles is even more difficult than that of spherical particles due to the need to detect contact between the particles. In this thesis, an efficient and robust ultra-packing algorithm termed Modified Drop-Fall-Shake is developed. The algorithm is used to simulate the real mixing process when manufacturing TIMs with hundreds of thousands ellipsoidal particles. The effective thermal conductivity of the particulate system is evaluated using an algorithm based on Random Network Model. </p> <p><br></p> <p>In problems where general free-form parametric surfaces (as opposed to the ellipsoidal fillers) need to be evolved inside a regular domain, the geometric distance from a point in the domain to the boundary is necessary to determine the influence of the moving boundary on the underlying domain approximation. Furthermore, during analysis, since the driving force behind interface evolution depends on locally computed curvatures and normals, it is ideal if the parametric entity is not approximated as piecewise-linear. To address this challenge,  an algebraic procedure is presented here to find the level sets of rational parametric surfaces commonly utilized by commercial CAD systems. The developed technique utilizes the resultant theory to construct implicit forms of parametric Bezier patches, level sets of which are termed algebraic level sets (ALS). Boolean compositions of the algebraic level sets are carried out using the theory of R-functions. The algebraic level sets and their gradients at a given point on the domain can also be used to project the point onto the immersed boundary. Beginning with a first-order algorithm, sequentially refined procedures culminating in a second-order projection algorithm are described for NURBS curves and surfaces. Examples are presented to illustrate the efficiency and robustness of the developed method. More importantly, the method is shown to be robust and able to generate valid solutions even for curves and surfaces with high local curvature or G<sub>0</sub> continuity---problems where the Newton--Raphson method fails due to discontinuity in the projected points or because the numerical iterations fail to converge to a solution, respectively. </p> <p><br></p> <p>Next, ALS is also extended for boundary representation (B-rep) models that are popularly used in CAD systems for modeling solids. B-rep model generally contains multiple NURBS patches due to the trimming feature used to construct such models, and as a result are not ``watertight" or mathematically compatible at patch edges. A time consuming geometry clean-up procedure is needed to preprocess geometry prior to finite element mesh generation using a B-rep model, which can take up to 70% of total analysis time according to literature. To avoid the need to clean up geometry and directly provide link between CAD and CAE integration,  signed algebraic level sets using novel inner/outer bounding box strategy is proposed for point classification of B-rep model. Several geometric examples are demonstrated, showing that this technique naturally models single patch NURBS geometry as well, and can deal with multiple patches involving planar trimming feature and Boolean operation. During the investigation of algebraic level sets, a complex self-intersection problem is also reported, especially for three-dimensional surface. The self-intersection may occur within an interval of interest during implicitization of a curve or surface since the implicitized curve or surface is not trimmed and extends to infinity. Although there is no robust and universal solution the problem, two potential solutions are provided and discussed in this thesis.</p> <p><br></p> <p>In order to improve the computational efficiency of analysis in immersed boundary problems, an efficient local refinement technique for both mesh and quadrature  using the kd-tree data structure is further proposed. The kd-tree sub-division is theoretically proved to be more efficient against traditional quad-/oct-tree subdivision methods. In addition, an efficient local refinement strategy based on signed algebraic level sets is proposed to divide the cells. The efficiency of kd-tree based mesh refinement and adaptive quadrature is later shown through numerical examples comparing with oct-tree subdivision, revealing significant reduction of degrees of freedom and quadrature points.</p> <p><br></p> <p>Towards analysis of moving boundaries problems, an explicit interface tracking method termed enriched isogeometric analysis (EIGA) is adopted in this thesis. EIGA utilizes NURBS shape function for both geometry representation and field approximation. The behavior field is modeled by a weighted blending of the underlying domain approximation and enriching field, allowing high order continuity naturally. Since interface is explicitly represented, EIGA provides direct geometric information such as normals and curvatures. In addition, the blending procedure ensures strong enforced boundary conditions. An important moving boundary problem, namely, reaction-diffusion problem, is investigated using EIGA. In reaction-diffusion problems, the phase interfaces evolve due to chemical reaction and diffusion under multi-physics driven forces, such as mechanical, electrical, thermal, etc. Typical failure phenomenon due to reaction-diffusion problems include void formation and intermetallic compound (IMC) growth. EIGA is applied to study factors and behavior patterns in these failure phenomenon, including void size, current direction, current density, etc. A full joint simulation is also conducted to study the degradation of solder joint under thermal aging and electromigration. </p>
639

Poruchy stability a chůze u extrapyramidových onemocnění / Balance and gait disorders in movement disorders

Hoskovcová, Martina January 2016 (has links)
Gait and balance disorders and the resulting falls are a substantial part of Parkinson's disease (PD) and other movement disorders. Especially in the late stage of PD more than 80 % of the patients fall. History of falls remains the best predictor of falls nonetheless, but it can not be used in falls prevention. Dopaminergic pharmacotherapy improves postural stability and gait in PD only in the early stage and the dopaminergic responsiveness of these symptoms decreases significantly during the disease progression. The impact of this medication on future falls risk remains still unclear. The connection between balance and gait disorders and cognitive impairment in PD is also not fully understood. The current state of knowledge about gait and balance disorders and cognitive impairment in PD is not satisfactory. Therefore the aims of the experimental part of this thesis were prospective monitoring of risk factors and predictors of falls, observation of the impact of dopaminergic medication on future falls risk and verifying the relationship between gait and balance disorders and cognitive impairment in PD. The fourth aim of the thesis was to specify the type and severity of gait and balance disorders in patients with essential tremor (ET). Although ET is one of the most common neurological disorders,...
640

Hodnocení efektu různých typů chůze na posturální stabilitu u zdravých seniorů - literární rešerše / Evaluation of the effects of different walking types on the postural stability in healthy seniors - a systematic review.

Novotová, Klára January 2021 (has links)
Title: Evaluation of the effects of different walking types on the postural stability in healthy seniors - a systematic review. Objective: The main objective of this diploma thesis is the evaluation of the impact of different types of walking on the postural stability in healthy elderly, based on the available resources corresponding to the established inclusion criteria. Force platforms were used as the tool to evaluate and to objectify postural stability in all studies included. These platforms are capable of measurement the level of postural stability by recording stance excursions in multiple directions. This thesis makes efforts to review the level of the possible future inclusion of different walking types in the process of physical therapy among older patients, regarding to improve the postural stability as well as the fall prevention in these patients. The next goals of this diploma thesis are to determine which type of walking appears to be the most efficient comprising the fall prevention as well as to assess the optimal frequency of the ordinary walking performance to achieve the same objective. Methods: This diploma thesis is processed in the form of a systematic review based on the available literary resources. First part of the thesis comprises the theoretical basis and the...

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