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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.
111

Progression and onset of undercut slope failure observed by surface velocity in physical models subjected to arch action / アーチ作用を受けた法尻掘削破壊進行とその誘因に関する表面速度に着目した物理模型実験

Fang, Kun 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21748号 / 工博第4565号 / 新制||工||1712(附属図書館) / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 大津 宏康, 准教授 PIPATPONGSA Thirapong, 教授 三村 衛 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
112

Vývoj morfologie patra a tvaru zubního oblouku u pacienta s rozštěpem / Development of the palate morphology and dental arch form in cleft patients

Urbanová, Wanda January 2013 (has links)
Development of the palate morphology and shape of the dental arch in patients with cleft Objective: The aim of this study was to compare the differences in development of the palate morphology and in the relationship and shape of the dental arches in two groups of individuals with different types of orofacial cleft defects. Introduction: Orofacial clefts are the cause of the insufficient growth of the face. Range of the resulting deformation depends on the type of cleft, individual growth disposition of the patient and comprehensive interdisciplinary treatment of the cleft. Material and Methods: The sample consisted of 18 patients with unilateral cleft lip and palate and 18 patients with isolated cleft palate. Measurements were performed on study casts of patients aged 9 and 13 years in average. Following measurements were performed: the frontal and distal width of the upper and lower dental arch, the length of both halves of the upper dental arches, the frontal length and depth of the upper dental arch and the overjet. According to the sagittal relationship of the dental arches, patients were classified into one of five categories of the GOSLON yardstick score. The results were compared between groups and between both age periods using one- or two-sample Wilcoxon test and Fisher test for the GOSLON...
113

Surface changes and screw loosening of the titanium abutments for one-piece implant supported fixed complete denture.

Qazali, Ahmad A. 08 November 2016 (has links)
No description available.
114

POSTURAL ADAPTATIONS IN ARCHWIRE EXPANSION WITH SELF-LIGATING BRACKETS

Padilla, Mark Thomas January 2014 (has links)
Objectives: Orthodontic arch development expands and broadens the dentition beyond the confines of the original arch perimeter. This is often accomplished by means of self-ligating fixed appliances. When movements take the teeth outside those confines, without adoption, the muscular forces are unbalanced and may lead to dental relapse. Muscle spindles and associated reflex loops within the tongue provide feedback to arch perimeter changes that may produce postural changes to the new archform. Resting posture has long been accepted as aiding in tooth position. The objective of this study was to assess the oral and pharyngeal postural changes that result from arch development with the Damon system and report the amount of expansion accomplished. Methods: Pre- and post-treatment models and lateral cephalograms were collected on 69 previously treated orthodontic patients from four different private practices. Expansion was measured from the buccal cusp tips of the first and second premolars and first molars. A new cephalometric analysis was implemented to diagnose both variations in malocclusion and variations in posture of the head, neck, pharynx, hyoid bone and tongue. Results: Both tongue height and length increased, 2.9mm (P-value 0.001, SEM=1.06) and 3.76mm (P-value 0.00002, SEM=0.62) respectively, following posterior dental arch expansion using Damon archwires. Hyoid position was not significantly different. Conclusion: As dental arches are expanded the tongue increases in both length and height to fill the space and therefore may aid in stability during the retention phase of treatment. The lack of change in hyoid bone position, as one would expect with a rise in tongue position, might be explained by either slight changes in head position or the need to maintain the airway. / Oral Biology
115

Isotopic Studies of Plutonic and Metamorphic Rocks from the Frontenac Arch, Grenville Province of Ontario and from Islay, in the Southern Inner Hebrides of Scotland / Isotopic Studies of Plutonic and Metamorphic Rocks

Marcantonio, Franco 01 1900 (has links)
This thesis is missing either page 57 or 58. The other copies of this thesis do not have this page either. -Digitization Centre / This study is an investigation of two regions which were once part of the same Proterozoic margin: the Frontenac Axis in the Southeastern Grenville Province of Ontario, and the island of Islay in Scotland. Shieh (1985) performed an oxygen isotopic study on the granitic plutons and surrounding metasediments in the Frontenac terrane. For the granites south of the Rideau Lake Fault, he observed extremely high 18O/16O ratios of +14.0%o (relative to SHOW), whereas north of the fault, the plutons gave ratios of around 10%o. Five of the plutons in Shieh's study have been dated using U-Pb zircon geochronology, with the following results: Battersea -1165 ± 3 Ma, Lyndhurst -1166 ± 3 Ma, Perth Road -1166 ± 3 Ma, Crow Lake -1176 ± 2 Ma, and Westport -1076 ± 2 Ma. The zircon ages are younger than the depleted mantle Nd model ages obtained (1211 to 1480 Ma) and signify that the plutons may be derived from a mantle source with contamination by the older surrounding metasediments which have an average Nd model age of 1790 Ma. Correlation between initial Nd (ENd(t) from +1 to +3) and initial Sr (Esr(t) from +9 to +21) also shows a mixed origin for the plutons. However, oxygen isotopes show that contamination by marble may also have occurred. Two features distinguish the Frontenac terrane southeast of the Rideau Lake Fault (RLF) from the Central Metasedimentary Belt (CMB) to the northwest: 1) the anorogenic (i.e. within plate) chemical signatures of the plutons, which are similar to the Hid-Proterozoic anorogenic granites that occur throughout North America (Anderson, 1983); and 2) the unique zircon ages for the plutons south of the RLF (1166 to 1176 Ha) that occur nowhere else in the CMB. This implies that the two areas define different crustal terranes. However, since Penokean (ca. 1800 Ha) crustal extraction ages are found in both terranes they may represent displaced segments of a single Penokean continental margin. In Scotland, a gneiss terrane on Islay was always inferred to be part of the Archean Lewisian complex. However, isotopic evidence shows that the Islay terrane is early Proterozoic in age (1782 Ha by U-Pb zircon geochronology) and that it is juvenile mantle-derived material, not a reworking of Archean crust during the Proterozoic. As a result, two major implications for the crustal evolution of Northern Britain are: 1) the Grampian terrane, an area directly adjacent to the newly defined Proterozoic Islay block, is probably underlain by Proterozoic basement; and 2) Northern Britain can be included in the Lower Proterozoic reconstruction of the Laurentian Shield. The similar crustal extraction ages observed in the Grenville of Ontario and on Islay give proof that these areas were part of a major 1.8 to 1.9 Ga crustal formation event, stretching from the southwestern U.S. to Finland. / Thesis / Master of Science (MS)
116

Exploring the Effect of Ankle Braces on Foot Posture

Dickerson, Laura Carroll 28 April 2020 (has links)
Foot posture is an important characteristic that can affect kinematics, plantar loading, and injury risk. Arch height is one common aspect of foot posture, and it is estimated that about 60% of the population has normal arches while 40% of the population is either pes planus or pes cavus. It is important to be able to accurately and reliably assess foot posture characteristics in order to propose interventions that could prevent injuries due to abnormal foot alignment. However, despite multiple classification metrics, many of the devices that are commonly used for foot posture measurements are not economically feasible for smaller clinics or research labs. Therefore, the first purpose of this study was to develop an affordable device to measure different foot posture characteristics. The Foot Posture Measurement System was developed and can measure total foot length, truncated foot length, foot width, dorsum height, and navicular height. This system was shown to have good to excellent validity (ICC = 0.908-0.994) and repeatability (ICC = 0.867-0.996) when compared to a 3D scanner. This device was then used in the second portion of this study, which evaluated the effects of ankle braces on plantar loading patterns in individuals with different foot postures. Contact area, peak force, force-time integral, and center of pressure were evaluated during a walk, run, and cut while the participant was unbraced, wearing a lace-up stabilizer brace, and wearing a semi-rigid brace. It was demonstrated that arch height did affect the maximum plantar forces during all tasks (p=0.001-0.047), as hypothesized based on previous studies. Additionally, this study found that ankle braces affected contact area (p=0.001-0.0014), maximum force (p<0.001 – p=0.043), and force-time integral (p<0.001 – p=0.015) during the walk, run, and cut. This is a novel finding and points to the potential for an impact of ankle braces on plantar loading during athletic activities, independent of foot type. / Master of Science / Foot posture is an important characteristic that can affect daily life and contribute to the risk of injury. Arch height is one common aspect of foot posture, and it is estimated that about 60% of the population has normal arches while 40% of the population is either high arched or low arched/flat footed. It is important to be able to accurately and reliably assess foot posture characteristics in order to propose interventions that could prevent injuries due to abnormal foot alignment. However, despite multiple classification metrics, many of the devices that are commonly used for foot posture measurements are not economically feasible for smaller clinics or research labs. Therefore, the first purpose of this study was to develop an affordable device to measure different foot posture characteristics. The Foot Posture Measurement System was developed and can measure five different length, width, and height characteristics of the foot. This system was shown to be valid when compared to a 3D scanner and repeatable between days. This device was then used in the second portion of this study, which evaluated the effects of ankle braces on individuals with different foot postures. Four different force and pressure variables were examined within the foot during a walk, run, and cut while the participant was unbraced, wearing a lace-up stabilizer brace, and wearing a semi-rigid brace. It was shown that arch height did alter plantar loading measures during all tasks, as hypothesized based on previous studies. Additionally, this study found that ankle braces affected all variables during the walk, run, and cut. This is a novel finding and points to the potential for an impact of ankle braces on plantar loading during athletic activities, independent of foot type.
117

The Stone and the Children's House

Rollins, Michael Johannes 06 June 2014 (has links)
The architect operates in both physical and spatial media. When in the presence of architectural form, an observer exists within the volume defined by surface and within the context of constructive material. At once the presence of architecture is imbued through spatial awareness, texture, sound, weight, light, shadow; material and volume modulate the senses to create the architectural experience. Montessori education is a pedagogy based on the development of a child's natural curiosity and intuition. The Guides lead rather than teach, encouraging the student to explore through activity. The student's intuitive exploration cannot be dictated or controlled by environment; the architect's role in education, therefore, is to work within his or her craft to create an "experiential architecture", one that utilizes the context of pedagogy, site, and material to develop a series of spaces to inspire within the individual a feeling unique to each. The architect must understand the nature of material, the way in which it wants to be used, to create an experience in which the architecture speaks of its making. The craft of building, then, becomes an architectural experience operating alongside the art of spatial composition. This school is the vehicle for exploring the dialogue between the spatiality and materiality of architecture. / Master of Architecture
118

Analysis of the deflections, vibrations, and stability of leaning arches

Hou, Aili 07 October 2005 (has links)
In recent years, leaning arches have been used in frameworks for some tent structures. Various people have studied the behavior of a single vertical arch; however, only a few researchers have considered the three-dimensional behavior of arches and leaning arches. The objective of this thesis is to analyze the three-dimensional nonlinear behavior of leaning arches, particularly the load-deflection and load-frequency relationships, and to provide a basis for future design guidelines. In this study, vertical arches of different shapes and load combinations are analyzed in order to compare with previous results given by other researchers. Then, the behavior of single tilted arches with different tilt angles is considered. Finally, a leaning arch structure, with two arches inclined to each other and joined at the top, is considered. The load displacement and load-frequency relationships, as well as some buckling modes, are discussed and presented in both tabular and graphical formats. / Master of Science
119

Equilibrium of a shallow arch subjected to PZT actuators and a deadweight load

Singh, Nitish 17 December 2008 (has links)
The geometrically nonlinear response of a shallow, circular, cylindrical panel under a midspan line load and induced strain actuation is presented. The panel is a laminate of piezoelectric material perfectly bonded to the convex and concave surfaces of a core of passive material. Since the curved edges are free and the straight edges are pinned a fixed distance apart, the response of the panel is independent of the axial coordinate. Hence, the governing ordinary differential equations are of the same form as for a shallow circular arch. Without induced strain actuation, the panel exhibits snap-through behavior under the midspan load. Induced strain distributions are determined at a constant midspan load to displace the panel to an inverted configuration in a stable manner. This adaptive structure may find application as an electromechanical, nonlinear spring with a digital-like, load-displacement response characteristic. / Master of Science
120

Análise da volatilidade dos mercados de renda fixa e renda variável de países emergentes e desenvolvidos no período de 2000 a 2011 / Analysis of volatility of fixed income market and stock market of emerging and developed countries in the period 2000-2011

Rossetti, Nara 15 August 2013 (has links)
O presente trabalho analisou as volatilidades dos mercados de renda fixa e variável de onze países, sendo eles: Brasil, Rússia, Índia, China, África do Sul (neste país apenas renda fixa), Argentina, Chile, México, Estados Unidos, Alemanha e Japão no período de janeiro de 2000 a dezembro de 2011. Os indicadores utilizados para representar cada mercado foram os índices dos mercados de ações e as taxas de juros interbancárias. Para tanto, o estudo se utilizou de modelos de heterocedasticidade condicional auto-regressiva: ARCH, GARCH, EGARCH, TGARCH e PGARCH, verificando quais destes processos eram mais eficientes para modelagem da volatilidade dos mercados dos países da amostra. Esta pesquisa também verificou qual dos modelos (ARIMA ou modelos GARCH e suas extensões) conseguiria prever melhor as séries de tempo analisadas. Além disso, por meio dos índices de correlação, covariância e causalidade Granger, foram comparados os retornos e a volatilidade do mercado de ações entre os países BRIC, entre os países latinos americanos e entre os países desenvolvidos e o Brasil. Os resultados sugerem que a volatilidade, tanto do mercado de renda fixa quanto do mercado de renda variável, é mais bem modelada por processos GARCH assimétricos (EGARCH e TGARCH), demonstrando efeitos de alavancagem nas séries estudadas. Quanto aos modelos de previsão, os modelos ARIMA, também para os dois mercados, mostrou-se mais eficiente que os modelos GARCH e suas extensões. Além disso, as volatilidades dos mercados de ações entre os países analisados parecem ser mais correlacionadas e possuir maior causalidade Granger do que os retornos destes países. Entre os dois mercados, renda fixa e variável dentro de cada país, as correlações dos retornos e da volatilidade são muito baixas, em algumas vezes negativa, e há pouca relação de causalidade Granger. / This study analyzed the volatility of fixed income and stocks markets for eleven countries, namely: Brazil, Russia, India, China, South Africa (just fixed income), Argentina, Chile, Mexico, United States, Germany and Japan from January 2000 to December 2011, using interbank interest rate as a fixed income market indicator and stock index to each country, as a stock market indicator. Therefore, the study used models of autoregressive conditional heteroscedasticity: ARCH, GARCH, EGARCH, TGARCH e PGARCH to verify which of these processes were more effective for in volatility modeling in each country. This research also found that the models (ARIMA or GARCH models and their extensions) could be used as the best forecast models. Moreover, by means of correlation coefficients, covariance and Granger causality, were used to compare the returns and volatility of the stock market among the BRIC countries, among the Latin American countries and between developed countries and Brazil. The results suggest that the volatility of both the fixed income market as the stock market is best modeled by processes asymmetric GARCH (EGARCH and TGARCH) demonstrating leverage effects in the time series. Regarding prediction ARIMA models was more efficient for both markets than GARCH models and extensions. In addition, the volatility of stock markets across countries analyzed seem to be more correlated and have higher Granger causality than returns these countries. Between the two markets, for each country, the correlations of returns and volatility are very low, if not positive, and there is low Granger causality.

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