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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.
71

A Comparison of Two Theological Student Groups in Relation to Theological Views, Rigidity and Political-economic Conservatism

Oswald, Robert M. 01 1900 (has links)
The present investigation was designed to explore the relationship between authoritarianism, rigidity, political-economic conservatism and theological beliefs of two groups of students representing two nationally known theological seminaries. One seminary is noted for its conservative theological standing, the other for its liberal position.
72

Návrh úpravy rámu 3D FDM delta tiskárny pro zvýšení kvality tisku / Modification of 3D FDM delta printer frame for improvement of print quality

Butakov, Aleksandr January 2020 (has links)
This work is focused on solving the problems of delta 3d printer frame rigidity and impact of rigidity on final quality of 3d printing. A variant of a 3d printer on a classic Kossel-shaped frame has designed and built. Further, frame strength analysis and improvement design is performed, with subsequent production of a new variant and comparison of the 3d printing results of both variants. The result of this work is to show how the frame construction really affects the print quality.
73

Perceptual rigidity in Parkinson's disease and normal aging

Diaz-Santos, Mirella 18 November 2015 (has links)
Parkinson's disease (PD) is characterized by rigidity symptoms that extend motoric symptoms, including cognitive rigidity (e.g., reduced cognitive set-shifting) and "rigid" personality (e.g., reduced novelty-seeking). These non-motor symptoms have been associated with fronto-striatal dysfunction in this disorder. Disruption of fronto-parietal attentional networks in PD suggests rigidity may extend to perception. To examine perceptual rigidity, non-demented individuals with mild-moderate PD (16-27/experiment), matched normal control (NC; 15-25/experiment) and young control adults (YC; 17-22/experiment) were presented with bistable images. Study 1 examined perceptual flexibility in normal aging. The Necker cube, a bistable image that can be perceived as having the upper-left or lower-right face in front, was presented under passive-viewing and two volitional-control conditions: hold one percept in front, and switch between the two percepts. Under passive viewing, dominance durations (time spent on each percept) were shorter in YC than NC. Relative to YC, NC were less able to increase dominance durations in the hold condition but were comparable in the switch condition. Study 2 applied the Necker-cube experiment to PD and extended it to passive viewing during binocular rivalry. Inconsistently with our hypotheses, PD showed comparable dominance durations to NC in the passive viewing – Necker cube, while demonstrating shorter dominance durations (equivalent to faster perceptual alternation) during binocular rivalry. Relative to passive viewing, PD showed a trend toward less ability than NC to increase dominance durations in the Hold condition, and were significantly less able than NC to reduce dominance durations in the Switch condition, both results indicative of perceptual rigidity. Dominance durations on passive viewing correlated with personality (novelty-seeking) in PD, and not with cognitive rigidity in either group. Study 3 examined whether enhancement of low-level visual cues would reduce perceptual rigidity in PD. Low level cues helped both PD and NC to exert better control over the conditions they did not demonstrate difficulties in Study 1 and Study 2. These results suggest that perceptual rigidity occurs in mild-moderate PD. The provision of cues, however, does not compensate for this rigidity. Finally, these results further suggest an association in PD between novelty-seeking and the ability to explore the perceptually ambiguous world. / 2017-11-18T00:00:00Z
74

Accurate and Robust Mechanical Modeling of Proteins

Fox, Naomi 01 February 2013 (has links)
Through their motion, proteins perform essential functions in the living cell. Although we cannot observe protein motion directly, over 68,000 crystal structures are freely available from the Protein Data Bank. Computational protein rigidity analysis systems leverage this data, building a mechanical model from atoms and pairwise interactions determined from a static 3D structure. The rigid and flexible components of the model are then calculated with a pebble game algorithm, predicting a protein's flexibility with much more computational efficiency than physical simulation. In prior work with rigidity analysis systems, the available modeling options were hard-coded, and evaluation was limited to case studies. The focus of this thesis is improving accuracy and robustness of rigidity analysis systems. The first contribution is in new approaches to mechanical modeling of noncovalent interactions, namely hydrogen bonds and hydrophobic interactions. Unlike covalent bonds, the behavior of these interactions varies with their energies. I systematically investigate energy-refined modeling of these interactions. Included in this is a method to assign a score to a predicted cluster decomposition, adapted from the B-cubed score from information retrieval. Another contribution of this thesis is in new approaches to measuring the robustness of rigidity analysis results. The protein's fold is held in place by weak, noncovalent interactions, known to break and form during natural fluctuations. Rigidity analysis has been conventionally performed on only a single snapshot, rather than on an entire trajectory, and no information was made available on the sensitivity of the clusters to variations in the interaction network. I propose an approach to measure the robustness of rigidity results, by studying how detrimental the loss of a single interaction may be to a cluster's rigidity. The accompanying study shows that, when present, highly critical interactions are concentrated around the active site, indicating that nature has designed a very versatile system for transitioning between unique conformations. Over the course of this thesis, we develop the KINARI library for experimenting with extensions to rigidity analysis. The modular design of the software allows for easy extensions and tool development. A specific feature is the inclusion of several modeling options, allowing more freedom in exploring biological hypotheses and future benchmarking experiments.
75

Synthesis and Characterization of Ligands and Transition Metal Complexes Containing M-Terphenyl Scaffolds

Ma, Liqing January 2007 (has links)
No description available.
76

INVESTIGATION OF NONLINEAR DYNAMICAL MODELS FOR OPTIMIZATION OF DEEP BRAIN STIMULATION

Rellinger, Benjamin Addison 10 December 2008 (has links)
No description available.
77

Measurement and Design of Flexural Rigidity of Microtubules and Their Application to Control Microtubule Collective Motions / 微小管の曲げ剛性の測定とその設計技術の微小管集団運動制御への応用

Zhou, Hang 23 March 2022 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第23885号 / 工博第4972号 / 新制||工||1776(附属図書館) / 京都大学大学院工学研究科マイクロエンジニアリング専攻 / (主査)教授 横川 隆司, 教授 安達 泰治, 教授 井上 康博 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
78

Recurrence Properties of Measure-Preserving Actions of Abelian Groups and Applications

Ackelsberg, Ethan 01 September 2022 (has links)
No description available.
79

One-Dimensional Dynamics: from Poincaré to Renormalization / Endimensionell dynamik: från Poincaré till omnormalisering

Dong, Yiheng January 2023 (has links)
Renormalization is a powerful tool showing up in different contexts of mathematics and physics. In the context of circle diffeomorphisms, the renormalization operator acts like a microscope and allows to study the dynamics of a circle diffeomorphism on a small scale. The convergence of renormalization leads to a proof of the so-called rigidity theorem, which classifies the dynamics of circle diffeomorphisms geometrically: the conjugacy between $C^3$ circle diffeomorphism with Diophantine rotation number and the corresponding rotation is $C^1$. In this thesis, we define the renormalization of circle diffeomorphisms and study its dynamics. In particular, we prove that the renormalization of orientation preserving $C^3$ circle diffeomorphisms with irrational rotation number of bounded type converges to rotations at exponential speed. We also introduce the necessary relevant concepts such as rotation number, distortion and non-linearity and discuss some of their properties. This thesis is a summary and supplement to the book One-Dimensional Dynamics: from Poincaré to Renormalization. / Omnormalisering är en kraftfull teknik som dyker upp i olika sammanhang inom matematik och fysik. I samband med cirkeldiffeomorfier är omnormaliseringsoperatorn ett dynamiskt system, som fungerar som ett mikroskop och gör att vi kan studera dynamiken hos en cirkeldiffeomorfi på en liten skala. Omnormaliseringens konvergens leder till ett bevis för det så kallade rigiditetssatsen, som klassificerar dynamiken hos cirkeldiffeomorfier geometriskt: konjugatet mellan $C^3$ cirkeldiffeomorfi med diofantiska rotationstal och den motsvarande rotationen är $C^1$. I denna avhandling definierar vi omnormaliseringen av cirkeldiffeomorfier och studerar dess dynamik. I synnerhet bevisar vi att omnormaliseringen av orienteringsbevarande $C^3$ cirkeldiffeomorfier med irrationellt rotationstal av begränsad typ konvergerar till rotationer med exponentiell hastighet. Vi introducerar också nödvändiga och relevanta begrepp så som rotationstal, distorsion och icke-linjäritet och diskuterar några av deras egenskaper. Denna avhandling är en sammanfattning och ett komplement till boken One- Dimensional Dynamics: from Poincaré to Renormalization.
80

Lateral torsional buckling of rectangular reinforced concrete beams

Kalkan, Ilker 10 November 2009 (has links)
The study presents the results of an experimental and analytical investigation aimed at examining the lateral stability of rectangular reinforced concrete slender beams. In the experimental part of the investigation, a total of eleven reinforced concrete beams having a depth to width ratio between 10.20 and 12.45 and a length to width ratio between 96 and 156 were tested. Beam thickness, depth and unbraced length were 1.5 to 3.0 in., 18 to 44 in., and 12 to 39.75 ft, respectively. Each beam was subjected to a single concentrated load applied at midspan by means of a gravity load simulator that allowed the load to always remain vertical when the section displaces out of plane. The loading mechanism minimized the lateral translational and rotational restraints at the load application point to simulate the nature of gravity load. Each beam was simply-supported in and out of plane at the ends. The supports allowed warping deformations, yet prevented twisting rotations at the beam ends. In the analytical part of the study, a formula was developed for determining the critical loads of lateral torsional buckling of rectangular reinforced concrete beams free from initial geometric imperfections. The influences of shrinkage cracking and inelastic stress-strain properties of concrete and the contribution of longitudinal reinforcement to the lateral stability are accounted for in the critical load formula. The experiments showed that the limit load of a concrete beam with initial geometric imperfections can be significantly lower than the critical load corresponding to its geometrically perfect configuration. Accordingly, a second formula was developed for the estimation of limit loads of reinforced concrete beams with initial lateral imperfections, by introducing the destabilizing effect of sweep to the critical load formula. The experimental results were compared to the proposed analytical solution and to various lateral torsional buckling solutions in the literature. The formulation proposed in the present study was found to agree well with the experimental results. The incorporation of the geometric and material nonlinearities into the formula makes the proposed solution superior to the previous lateral torsional buckling solutions for rectangular reinforced concrete beams.

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