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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.
51

Estudo comparativo da capacidade de ativação das molas espirais fechadas, determinada por carregamento axial de tração

Brito, Vladimir Nunes de 14 July 2018 (has links)
Orientador : Simonides Consani / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-07-14T14:35:03Z (GMT). No. of bitstreams: 1 Brito_VladimirNunesde_M.pdf: 770357 bytes, checksum: 3b28e968c036b66f5afdd4053dfa0acd (MD5) Previous issue date: 1981 / Resumo: O propõsito deste trabalho foi determinar a força de tração produzida pelas molas espirais fechadass ativadas por meio de carregamento axial de traçãos até gir o limite de deformação permanente. quando atinPara issos foram utilizados seis tipos de molas espirais fechadas fabricadas por Roc k Mount a i n (E 1g i 1oy ) s Uni te k (Hi -T) e Denta urum (Remani t ) . Os corpos de prova foram confeccionados com molas constru;das com fios de Os008 pol. (Os203 mm) e Os009 pol. (Os229 mm) de espessurass e cujos diâmetros correspondiam 'a 0,022 pol.(0,559 mm) ,0,030 pol. (Os762 mm) e 0,036 pol. (0,914 mm) / Abstract: Not informed. / Mestrado / Ortodontia / Mestre em Odontologia
52

Spanwise mixing in multi-stage axial compressors

Gallimore, Simon John January 1986 (has links)
No description available.
53

Diagnostic and Therapeutic Difficulties in Retroperitoneal Abscess

Tunuguntla, Anuradha, Raza, Rafi, Hudgins, Larry 01 November 2004 (has links)
Abscesses developing within the retroperitoneal spaces are complicated and serious infections. These abscesses present insidiously, leading to considerable mortality and morbidity. A high clinical suspicion can help diagnose and treat this potentially fatal illness. Computed axial tomography is the best diagnostic modality for retroperitoneal abscess. Computed tomographic scan is useful, not only for diagnosing the retroperitoneal abscess, but can be used for therapeutic drainage of abscesses in high-surgical-risk patients. We present an illustrative case of retroperitoneal abscess and discuss the pathogenesis of retroperitoneal abscess, diagnosis, and treatment.
54

Virtual Moving Air Gap for the Speed Range Improvement of a Dual Stator Axial Flux Motor

Mularcik, Bradley S. 02 July 2012 (has links)
No description available.
55

Identification and Evaluation of Loss and Deviation Models for use in Transonic Compressor Stage Performance Prediction

Cahill, Joseph E. 30 October 1997 (has links)
The correlation of cascade experimental data is one method for obtaining compressor stage characteristics. These correlations specify pressure loss and flow turning caused by the blades. Current open literature correlations used in streamline curvature codes are inadequate for general application to high-speed transonic axial-flow compressors. The objective of this research was to investigate and evaluate the available correlations and ultimately discover sets of correlations which best fit the empirical data to be used in streamline curvature codes. Correlations were evaluated against experimental data from NASA Rotor 1-B and NASA Stage 35. It was found that no universal set of correlations was valid for minimum-loss point predictions. The Bloch shock loss model showed promising results in the stall regime for supersonic relative inlet Mach numbers. The Hearsey and Creveling off-minimum-loss deviation angle prediction performed consistently better than all other correlations tested. / Master of Science
56

Dependence of Nuclear Energy on Axial Asymmetry and its Consequences

Das Gupta, Subal 08 1900 (has links)
An investigation is carried out to determine whether or not on the basis of theory one expects axial asymmetry in heavy nuclei. The average one-body potential well is taken as an anisotropic harmonic oscillator, modified by the usual ℓ ∙ s and ℓ² forces. The method of matrix diagonalisation is used to find the eigenvalues. Residual interaction between nucleons is also treated in the pairing approximation. The calculations show that prolate axial symmetry is favoured in each of the nuclei considered. It is possible to indicate the underlying physical reasons for this result. Assuming equilibrium prolate axial symmetry an attempt is made to understand the collective excited levels in the transition region, i.e. the region between spherical nuclei and permanently deformed nuclei. A model calculation is done to show how the levels can be obtained. / Thesis / Doctor of Philosophy (PhD)
57

Seismic Response of Deep Circular Tunnels Subjected to P- and S-waves

Chatuphat Savigamin (12451497) 25 April 2022 (has links)
<p>Most of the attention to the seismic performance of tunnels has been devoted to shear waves propagating in a direction perpendicular to the tunnel axis, with motion perpendicular to the tunnel axis, causing the so-called “ovaling or racking response”. Body waves, however, can travel through the ground and intersect the tunnel at different angles, thus inducing a complex seismic response that requires a comprehensive understanding of all modes of deformation. This study provides analytical solutions to capture the behavior of the liner and the surrounding ground, for a deep circular tunnel subjected to body waves, for all five possible modes of deformation: (i) axial compression-extension; (ii) transverse compression-extension; (iii) ovaling; (iv) axial shear; and (v) axial bending or snaking. The main assumptions used to derive the analytical solutions include: (i) the tunnel is deep and very long and has a circular cross section; (ii) the ground and the support are homogeneous and isotropic, and their response remains elastic; (iii) the interface between the ground and the liner is either no-slip or full-slip; (iv) the pseudo-static approach, i.e. inertia forces can be neglected, is acceptable to estimate seismic deformations; (v) for the transverse compression-extension and ovaling deformation modes, plane strain conditions in the direction of the tunnel axis apply at any cross section; and (vi) for the axial compression-extension and axial bending deformation modes, the wavelength of the seismic motions is much larger than the tunnel radius. Two and three-dimensional numerical simulations with the finite element codes ABAQUS, for static drained/undrained loading and dynamic drained loading conditions, and MIDAS GTS NX, for dynamic undrained loading conditions, are carried out to validate the analytical solutions and further investigate the seismic response of the tunnel. All the comparison results show good agreement between the analytical and numerical solutions.</p> <p>Dynamic amplification effects on the tunnel cross section are studied for the axial compression-extension, transverse compression-extension, and axial bending deformation modes, through a set of dynamic time-history models where the input frequency of the far-field seismic motion is changed. The results reveal the limits of the analytical solutions, in the form of minimum wavelength-to-tunnel diameter (/D) ratios such that the errors are less than twenty percent, including: (i) 25 (drained) and 20 (undrained) for axial compression-extension; (ii) 25 (drained) and 12.5 (undrained) for transverse compression- extension; and (iii) 7.5 (unsupported tunnel), 7.5 (supported tunnel with no-slip interface), and 12.5 (supported tunnel with full-slip interface) for axial bending or snaking. These ratios are also the limits of applicability of quasi-static (instead of dynamic) numerical simulations to estimate the seismic behavior of the liner and the surrounding ground.</p>
58

Reinforced concrete column behavior under cyclic loading

熊朝暉, Xiong, Zhaohui. January 2001 (has links)
published_or_final_version / Civil Engineering / Doctoral / Doctor of Philosophy
59

Micromechanical modelling of unidirectional composites subjected to external and internal loadings

Nedele, Martin Rolf January 1996 (has links)
No description available.
60

The dynamic and static plastic collapse of structural members incorporating axial stiffening

Birch, R. S. January 1987 (has links)
No description available.

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