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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.
131

Space frame analysis

Lin, Fu Tien 16 February 2010 (has links)
The principal objective of th1s thesis has been accomplished. The technique for the analysis of a space frame has been developed and described. A computer program has been wr1tten and presented. A test frame was constructed, analyzed and tested and the results for deflections and rotations compared. / Master of Science
132

Analysis and Testing of a Ready-to-Assemble Wood Framing System

Kochkin, Vladimir G. 15 September 2000 (has links)
The concept of a ready-to-assemble kit fabricated in a factory and delivered to the customer is well known and commonly used by the furniture industry. In wood construction, the lack of a simple and reliable method of assembling the frame members creates a barrier to wide acceptance of prefabricated kit structures. This thesis focuses on a novel technology of assembling structural components of a wood frame using a metal nail plate connector (NPC). This technology was referred to as a ready-to-assemble (RTA) wood framing system. The RTA system simplifies the framing process and allows for rapid erection of a wood structural frame by a small nonprofessional crew. A 16 x 24 foot RTA building was constructed to demonstrate the feasibility of the RTA system concept. An effective assembly sequence was proposed and successfully implemented. The design procedure for the RTA buildings was presented. The lateral load path for the RTA building includes diaphragms and shear walls. The contribution of the RTA frame can be ignored from the lateral load analysis. This conclusion was validated for the diaphragms with aspect ratios up to 4:1. The finite element method was used to model the RTA structures. The models incorporated semi-rigid behavior of the NPC. An analytical model was developed to predict the nonlinear moment-rotation relationship of the NPC. The proposed model showed a good agreement (R2=0.98) with the experimental data. Tests were conducted to measure the load-drift response of the RTA shear walls. / Master of Science
133

Comparison of P-Delta Analyses of Plane Frames Using Commercial Structural Analysis Programs and Current AISC Design Specifications

Schimizze, Angela Marie 08 May 2001 (has links)
Several different approaches to determining second-order moments in plane frames were studied during this research. The focus of the research was to compare the moments predicted by four different commercially available computer analysis programs and the current design specification, the AISC LRFD moment magnification method. For this research, the second-order moments for ten commonly designed frames were compared. An overview of various second-order analysis procedures is presented first. The solution procedure utilized by each computer program and the AISC moment magnification method are explained. Also, the frames considered in the research are described. Next the frames are analyzed and the results between each of the computer programs and the current design specifications are compared. Finally, conclusions are drawn concerning the consistency of the second-order moments predicted by each of the solution procedures and recommendations for their use are discussed. In general, each of the four computer analysis programs evaluated and the AISC moment magnification method can consistently and adequately predict the second-order moments in plane frames. / Master of Science
134

An Analogical Garden of Memory

Vermillion, Emma Flower 14 August 2022 (has links)
An architect draws from a deep repository of past memories made durable in the act of architecture. This thesis is a study of the analogous relationship between a childhood memory of a garden and a set of architectural acts giving form to this memory. The ideas of threshold, meander, focus, and framing are the basic conditions of the project. Perspectives and montages are the primary methods of study. The project is a garden placed within the context of an imagined city setting up the interplay of silence amidst the cacophony of the city. It centers around a singular tree, informed by a specific childhood memory. The single tree in concert with the architectural conditions allows one to resist the inexorable rush of urban time. / Master of Architecture / An architect draws from memories of the past to inform the future. This thesis is a study that pulls from memories of a childhood garden and compares them to a set of basic architectural elements. The ideas of threshold, meander, focus, and framing are explored.
135

LRFD evaluation of full-scale metal building rigid frame tests

Davis, Douglas Bradley 22 August 2008 (has links)
Metal building companies commonly use rigid frames to meet the requirement of large, open spaces which are unobstructed by interior columns. These rigid frames are optimally designed and constructed using tapered columns and rafters, connected at the knees and ridge by moment end-plate connections. The purpose of this research was to investigate the accuracy of standard analysis methods when applied to metal building rigid frames. To achieve this goal, the results of two full-scale metal building rigid frame tests were compared to predicted values obtained from typical analysis procedures. Upon completion of the tests, measured dimensions and material properties were used to perform linearly elastic frame analyses and 1993 AISC LRFD Specification strength checks. It was concluded that standard analysis procedures are very accurate when applied to rigid frames such as the ones in this study. The provisions concerning lateral-torsional buckling of singly-tapered segments were found to inappropriately contain AISC ASD factors of safety. New provisions were developed and recommended to correct this problem. The suggested provisions were found to be slightly more conservative than the existing provisions for the frames in this study. / Master of Science
136

A many-dimensional approach to simulations in modal logic

Cloete, Walter (Walter Theophilus Woldemar) 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Truth preservation is an important topic in model theory. However a brief examination of the models for a logic often show that isomorphism is needlessly restrictive as a truth preserving construction. In the case of modal logics with Kripke semantics the notions of simulation and bisimulation prove far more practical and interesting than isomorphism. We present and study these various notions, followed by a discussion of Shehtman’s frame product as semantics for certain many-dimensional modal logics. We show how simulations and bisimulations can be interpreted inside models over frame products. This is followed by a discussion on a category-theoretic setting for frame products, where the arrows may run between frames with different types. / AFRIKAANSE OPSOMMING: Die behou van waarheid is ’n prominente onderwerp in modelteorie. ’n Vlugtige ondersoek van die modelle vir ’n besondere logika wys egter dat isomorfisme onnodig beperkend as waarheid-behoudende konstruksie is. In die geval van modale logika met Kripke se semantiek is simulasie en bisimulasie heelwat meer prakties en interessant as isomorfisme. Na die bekendstel en studie van hierdie onderskeie begrippe bespreek ons Shehtman se raamproduk as semantiek vir sekere meer-dimensionele modale logikas. Ons wys ons hoe simulasies en bisimulasies binne modelle oor sulke raamprodukte geïnterpreteer kan word. Daarna bespreek ons ’n kategorie-teoretiese konteks vir raamprodukte, waar die pyle tussen rame met verskillende tipes mag loop.
137

Skewed Cross Frame Connection Stiffness

Battistini, Anthony David 20 September 2010 (has links)
Cross frames and diaphragms are essential to the stability of straight steel girder bridge systems as they help to resist lateral torsional buckling during construction and horizontal loading conditions. In skewed bridge systems, cross frames are often oriented parallel to the supports and hence, at an angle to the girder. To facilitate construction fit-up, plates, bent to match the skew angle, form the cross frame to stiffener connection. While the bent plate connection is a simple solution, it could introduce undesirable flexibility into the system, potentially compromising the effective brace stiffness. A proposed detail utilizing half pipe stiffeners may provide enhanced structural performance, while possibly reducing overall fabrication costs. Field and laboratory tests to determine the stiffness of both connection types are presented in the thesis. / text
138

框架為本之分類詞分析:以台灣華語為例 / A Frame-based Approach to Classifiers:A Case Study of Taiwan Mandarin

謝禎田, Hsieh, Chen tien Unknown Date (has links)
本篇論文從認知語意學的角度來探討分類詞的本質,並且結合了Fillmore (1975) 的框架 (frame) 理論和Langacker (1987) 的顯影(profiling) 概念,作為分析的理論基礎,說明語言如何透過分類詞機制來凸顯名詞在認知上的某些語意特徵。本論文所嘗試提出的理論架構最終目的在於解釋所有的分類詞語言,但為提昇語料的可信度,語料來源以台灣華語中的分類詞為主。 研究分析主要建構於名物框架 (N-frame) 的認知基礎上,進而檢視台灣華語中不同類別之名詞藉由不同之分類詞所彰顯的語意特徵 (feature),同樣重要的是不同的語意特徵在台灣華語分類詞系統中的優先排序。最後我們從其他的分類詞語言中,如閩南語及日語,論證名物框架系及彰顯機制統的普遍性;唯不同的分類詞語言或不同方言中所選擇顯影的語意特徵以及其優先排序都可能有所不同,分類詞系統也因此呈現複雜多樣的面貌。 / On the basis of the theory of Frame, proposed by Fillmore (1975), and the models of profile and base segregation, proposed by Langcker (1987), this thesis aims at a cognitive approach to explain how languages manifest certain cognitive features of a noun by means of classifiers. In addition, the theoretical framework tries to explain all the known classifier languages and to foster a greater accountability and reliability of the data, this study focuses on Taiwan Mandarin. The data analysis is based on the cognitive foundation of an N-frame, whereby it is found that Taiwan Mandarin categorizes nouns by profiling different features of nouns through the use of different classifiers. A hierarchy or ranking of classifier features in Taiwan Mandarin is also provided. Finally, in all known classifier languages, such as Southern Min and Japanese, it is found that the application of the use of an N-frame is consistent and universal in human cognition. The only thing that varies is the profiling system that each language employs and the hierarchy of features it selects. Thus, the use of classifiers manifests varied and complex aspects.
139

Evaluation of force distribution within a dual special moment-resisting and special concentric-brace frame system

Wearing, Christopher January 1900 (has links)
Master of Science / Department of Architectural Engineering and Construction Science / Kimberly W. Kramer / Dual Lateral Force Resisting Systems are currently required by code to include a Moment Resisting Frame capable of resisting at least 25% of the lateral loads. This thesis evaluates the seismic performance of a specific type of dual system: a Special Moment Resisting Frame-Special Concentric Brace Frame System (SMRF-SCBF) under three different force distributions. The three distributions were 80% - 20%, 75% - 25%, and 70% - 30% with the lesser force being allotted to the Special Moment Resisting Frame (SMRF) portion of the system. In order to evaluate the system, a parametric study was performed. The parametric study consisted of three SMRF-SCBF systems designed with different seismic force distributions. The aim of this study was to determine accuracy of the three different seismic force distributions. The accuracy was measured by comparing individual system models’ data and combined system models’ data. The data used for comparison included joint deflections (both horizontal and vertical), induced moments at moment connections, brace axial loads, column shears, and column base reactions. Two-dimensional models using the structural software RISA 3D were used to assist in designing the independent Seismic Force Resisting Systems. The designs of the frames were not finely tuned (smallest member size for strength), but were designed for drift (horizontal deflection) requirements and constructability issues. Connection designs were outside the scope of the study, except for constructability considerations – the SMRF and the SCBF did not have a common column; the frames were a bay apart connected with a link beam. The results indicated that a seismic force distribution of 75% to the SCBF and 25% to the SMRF most accurately predicts that frame’s behavior. A force distribution of 80% to the SCBF and 20% to the SMRF resulted in moderately accurate results as well. A vast opportunity for further research into this area of study exists. Alterations to the design process, consideration of wind loads, or additional force distributions are all recommended changes for further research into this topic.
140

Avaliação de características de desempenho e qualidade de carne em linhagens e touros representativos da raça Nelore, utilizando ultrassonografia, análise de imagens e NIRS / Evaluation of growth and beef quality traits in lineages and representative Nellore sires, using ultrasound, video image analysis and NIRS measurements

Bonin, Marina de Nadai 05 October 2012 (has links)
Esta pesquisa teve como objetivo avaliar as diferenças nos padrões de desenvolvimento ponderal, composição de carcaça e qualidade de carne entre linhagens e touros representativos da raça Nelore, com aplicação de tecnologias modernas para coleta de dados e estimação de parâmetros genéticos e fenotípicos das características em estudo. Foram utilizados dados de desenvolvimento ponderal, características de carcaça e qualidade de carne de machos da raça Nelore, terminados a pasto e confinamento e pertencentes a programas de avaliação genética. Desses animais, foram coletadas informações individuais de características de carcaça avaliadas por ultrassonografia e medidas corporais para estimação do frame de cada animal. Ao abate, foram avaliadas características de carcaça e carne, diretamente na carcaça e também através de imagens digitais do músculo Longissimus para determinação de atributos relacionados à qualidade, como maciez, perdas por cozimento, gordura intramuscular e pH. Avaliações por infravermelho com comprimentos de onda na faixa do visível próximo (VIS-NIRS) foram tomadas para associação com valores de pH, força de cisalhamento e lipídios no músculo Longissimus. Foram estimados parâmetros genéticos para todas as características avaliadas neste trabalho. As características de ganho ponderal, frame, medidas de ultrassonografia e qualidade de carne foram utilizadas para comparação entre genearcas e novos genearcas da raça Nelore. Estas informações em conjunto com a validação ferramentas auxiliares para coleta de fenótipos poderão ajudar na condução de programas de melhoramento genético de características de desempenho e qualidade de nos rebanhos dessa raça, bem como a obtenção de importantes informações sobre a variabilidade e valor genético de genearcas e touros representativos da raça Nelore. / The objective of this study was to evaluate the differences of growth, carcass composition and beef quality traits among lineages and representative Nellore sires, using new technologies to collect data and estimate genetic and phenotypic parameters. Data on growth, carcass and meat quality traits of Nellore bulls, raised in pastures and included in genetic evaluation programs were analyzed. Individual information on live ultrasound carcass measurements and frame were, also, collected. After slaughter, carcass, beef quality traits and video image analysis (VIA) of muscle Longissimus were obtained for estimation of beef quality attributes like tenderness, cooking losses, intramuscular fat and pH. Evaluations with Near Infrared Spectroscopy (VIS-NIRS) were made to quantify tenderness and lipid in Longissimus muscle. Genetic parameters were estimated for all traits analyzed in this study. Traits like performance, frame, ultrasound carcass evaluation and meat quality were used to compare lineages and representative Nellore sires. This research provide precious information to development of auxiliary tools for genetic improvement of growth, carcass and meat quality traits in Nellore herds, and provide important information about variability and genetic value of founders and representative sires of this breed.

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