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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.
151

Structural Analysis along the Grenville Front near Sudbury, Ontario

Hsu, Mao-Yang 07 1900 (has links)
<p> Amphibolites and gneisses of the "Grenville province" and granitic rocks of the Chief Lake batholith near Sudbury show the effects of several phases of deformation. </p> <p> The first phase of deformation affected previously metamorphosed rocks of the "Grenville province" together with enclosed pegmatite sills, and formed congruous parasitic S- and Z-folds. The rocks were then subjected to faulting and local refolding. About 1, 750 m. y. ago, the Chief Lake batholith was intruded and truncated the previous folds. Finally, all the rocks were subjected to a simultaneous regional metamorphism and strong deformation. </p> <p> During this final deformation, all the previous linear structures were rotated to parallel the strongly-developed regional mineral lineations. The high-grade rocks of high amphibolite facies to the S. E. of the cataclastic zone flowed upwards from a greater depth than the rocks of greenschist facies to the N. E. of the cataclastic zone. The sharp increase in metamorphic grade occurs within the cataclastic zone which is about one mile wide. </p> <p> The final progressive deformation of the rocks is compared with the constant-volume deformation ellipsoid as initiated from the uniaxial prolate type through the constriction type to the plane- strain type; wherein the direction of maximum elongation plunges moderately to the S. S. E. and parallels the regional mineral lineations, the passive fold axes, the elongations of conical folds, and the original flow directions (shown by deformed mineral lineations) of slip folds; while the direction of maximum shortening generally plunges to the N. W. and is normal to the penetrative foliations and the active axial planes of slip folds. </p> / Thesis / Master of Science (MSc)
152

Structural Analysis and Microstructural Examination of the Catoctin Formation in the South Mountain Anticline, Maryland

Spitzer, Robert 04 1900 (has links)
<p> Microstructural as well as structural analysis of amygdules and groundmass of the Catoctin F·ormation located in the overturned western limb of the South Mountain anticline permit interpretation pertaining to the nature of cleavage development. Various -metliods haye been employed in the structural analysis of amygdules, in order to ascertain their original shapes and also the nature of the tectonic strain ellipsoid. A deformation path has been constructed in logarithmic co-ordinates. This appears to be an improvement over the arithmatic graph of Wood (1974). Microstructural investigation allows recognition of two distinct domains within the groundmass and amygdules : i)an early schistosity and ii)a crenulation cleavage. Microstructural and structural analysis provide a logical explanation of this history. An initial flattening episode forming the early schistosity was followed by approximately plane strain deformation creating the crenulation cleavage. </p> / Thesis / Bachelor of Science (BSc)
153

Design and structural analysis of sofa frames

Dai, Li 15 December 2007 (has links)
This project’s goals are to evaluate the structure and strength design of Schnadig three-seat sofa frames, summarize current available information on engineering design, derive cyclic schedules for durability evaluation of frame components, and improve the design to meet product performance requirement specified by Schnadig. The target goal of medium or above acceptance level of General Service Administration (GSA) performance test was expected for the improved design. The design procedures and testing results in the study are also applicable to other frames, and can be used as a guideline for product engineering and reengineering. In this study, the mechanical and strength properties of frames, and members and joints, were evaluated. Schnadig three-seat sofa frames were evaluated by the performance tests. Six sets of tests were conducted with three replicates for each test. The critical joints and members were identified. Generally the frames did not reach the anticipated medium acceptance level except for the arm vertical test, where all the tested frames passed heavy duty. The inadequate connection of joints and the weak member were the major cause of failure. Next, the static and fatigue properties of selected plywood, oriented strand board (OSB) and particle board (PB) were investigated. The regression equations of S-N (stress versus number of cycles to failure) through low 5% points (i.e., the 5th percentile) were derived for all selected wood composite materials and proposed as design equations for achieving a conservative design of furniture frame structural members considering fatigue effects. It was found that the fitting constant E in the S-N equation at low 5% data was 0.85, and the constant H values were 0.06, 0.08, and 0.10, for plywood, OSB, and PB, respectively. Analysis results indicted that when cyclic stepped load effects were considered, the allowable design stress for plywood, OSB, and PB should not exceed respectively, 54%, 64%, and 68% of their MOR. Experiments were also designed to investigate the lateral shear and direct withdraw load resistances of face-toace and end-toace joints. Two types of connection, glue and single staple, were studied. Load direction relative to grain direction was considered. Statistical analyses were implemented to study the effect on the load resistance of the joints. Lastly, a solid 3D frame model was developed in I-DEAS to obtain the internal forces on critical components. Suggestions on the constructions of critical components were made based on internal forces obtained from computer modeling, as well as the laboratory results of frames, members, joints. One result of this study is the recommendations for improved construction details.
154

From Page to Page to Stage: Translation and Dramaturgy Issues of Once upon a Rainy Night

Xu, Junying 28 August 2008 (has links)
No description available.
155

An Analysis of High-Speed Impact Nailing for Lightweight Automotive Structures

Gotlib, Ilia January 2014 (has links)
No description available.
156

The finite element analysis of two-dimensional overlay pavement systems /

Buranarom, Chinawood January 1976 (has links)
No description available.
157

A Study of Finite Element Grid Optimizations

Ladesic, James G. 01 January 1973 (has links) (PDF)
Any structural analysis which gives stresses and displacements for some predefined structure is governed by some physical domain of loading, geometry and boundary conditions. Let this domain be called the structures "problem space." In applying finite element analysis, the solution to any one problem space may be one of many admissible solutions all of which satisfy some given set of boundary conditions. Admissibility is determined by the stated problem with its boundary conditions along with computer storage capacity considerations. Obtaining the most exact approximate solutions is one of major concern to insure adequate results. This problem has been approached from a number of viewpoints [4-9] all of which employ some version of minimum potential energy [5, 10]. This report is a study of current approaches to this problem and their effect on finite element grid optimizations. Selected optimizations [4-9] are shown to be effective in producing better solutions but it is noted that the implementation of these optimizations may be difficult. To survey the situation two fixed problem spaces of a tapered beam and a cantilever beam are chosen for investigation. Conclusions based on this study display that optimizations methods applied to a finite element model give an optimum space arrangement that is a function of the selected element geometry and displacement function. When changes in the element geometry are introduced a new optimum results. Comparing test problem results leads to some speculation employing uniform strain energy as a better guide to "first guess" grid arrangement and a recommendation for further investigation in this direction.
158

Structural Design Using Cellular Automata

Slotta, Douglas J. 22 June 2001 (has links)
Traditional parallel methods for structural design do not scale well. This thesis discusses the application of massively scalable cellular automata (CA) techniques to structural design. There are two sets of CA rules, one used to propagate stresses and strains, and one to perform design analysis. These rules can be applied serially, periodically, or concurrently, and Jacobi or Gauss-Seidel style updating can be done. These options are compared with respect to convergence, speed, and stability. / Master of Science
159

Um estudo da formulação de modelos constitutivos viscoelásticos e elasto-viscoplásticos e do emprego de algoritmos implícitos e explícitos para a sua integração numérica / A study of viscoelastics and elastoviscoplastics constitutive modelling and the use of implicit numerical integration algorithms

Munaiar Neto, Jorge 03 July 1998 (has links)
O presente trabalho trata da formulação de modelos constitutivos viscoelásticos e elasto-viscoplásticos nos apectos relativos à verificação da consistência termodinâmica, pela aplicação do Método do Estado Local, e de verificação da resposta numérica decorrente da utilização de um procedimento implícito de integração. No contexto da verificação da consistência termodinâmica, são revistos alguns arranjos unidimensionais de elementos reológicos básicos, analisando-se, com maior destaque, um arranjo misto denominado modelo elasto-viscoplástico completo. Nas análises numéricas em campo unidimensional e multiaxial, realiza-se um confronto entre as respostas obtidas com procedimentos de integração Explícito e Implícito, bem como um estudo para a definição do passo de tempo, de modo a garantir precisão nas respostas. / The present work treats of the formulation of viscoelastics and elastoviscoplastics constitutive models, on the aspects related to verification of the thermodynamic consistency, by the Method of Local State, and of numerical responses of a implicit integration scheme. In the context of the thermodynamic consistency, some unidimensional arrangements of basics rheological elements are reviewed, where a named elasto-viscoplastic extended model is enhanced. On what concerns to unidimensional and multiaxial numerical analysis, confront is showed between the results obtained from the explicit and implicit integration algorithms, and a study for time step definition aiming a good precision of the responses is presented as well.
160

Um estudo da formulação de modelos constitutivos viscoelásticos e elasto-viscoplásticos e do emprego de algoritmos implícitos e explícitos para a sua integração numérica / A study of viscoelastics and elastoviscoplastics constitutive modelling and the use of implicit numerical integration algorithms

Jorge Munaiar Neto 03 July 1998 (has links)
O presente trabalho trata da formulação de modelos constitutivos viscoelásticos e elasto-viscoplásticos nos apectos relativos à verificação da consistência termodinâmica, pela aplicação do Método do Estado Local, e de verificação da resposta numérica decorrente da utilização de um procedimento implícito de integração. No contexto da verificação da consistência termodinâmica, são revistos alguns arranjos unidimensionais de elementos reológicos básicos, analisando-se, com maior destaque, um arranjo misto denominado modelo elasto-viscoplástico completo. Nas análises numéricas em campo unidimensional e multiaxial, realiza-se um confronto entre as respostas obtidas com procedimentos de integração Explícito e Implícito, bem como um estudo para a definição do passo de tempo, de modo a garantir precisão nas respostas. / The present work treats of the formulation of viscoelastics and elastoviscoplastics constitutive models, on the aspects related to verification of the thermodynamic consistency, by the Method of Local State, and of numerical responses of a implicit integration scheme. In the context of the thermodynamic consistency, some unidimensional arrangements of basics rheological elements are reviewed, where a named elasto-viscoplastic extended model is enhanced. On what concerns to unidimensional and multiaxial numerical analysis, confront is showed between the results obtained from the explicit and implicit integration algorithms, and a study for time step definition aiming a good precision of the responses is presented as well.

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