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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.
31

Interaction domain in non-prestressed circular concrete bridge piers using simplified modified compression field theory

Abouelleil, Alaaeldin January 1900 (has links)
Master of Science / Department of Civil Engineering / Hayder Rasheed / The importance of the analysis of circular columns to accurately predict their ultimate confined capacity under shear-flexure-axial force interaction domain is recognized in light of the extreme load event imposed by the current AASHTO LRFD specification. In this study, various procedures for computing the shear strength are reviewed. Then, the current procedure adopted by AASHTO LRFD 2014, based on the simplified modified compression field theory, is evaluated for non-presetressed circular concrete bridge piers. This evaluation is benchmarked against experimental data available in the literature and against Response 2000 freeware program that depicts interaction diagrams based on AASHTO 1999 requirements. Differences in results are discussed and future improvements are proposed. A new approach is presented to improve the accuracy of AASHTO LRFD calculations. The main parameters that control the cross section shear strength are discussed based on the experimental results and comparisons.
32

Postavení a činnost autorizovaného inspektora podle stavebního zákona / The position and activities of an authorized inspector under the Building Act

Fisenková, Tereza January 2012 (has links)
Presented thesis deals with approved inspector as a major entity of simplified procedure. It is focused on the origin of his function, internal organization and impact of his functioning. Author brings comprehensive view of current problems, primarily from point of view of judicature, specialized literature and comparison with foreign legislation. Author considers a possibility of amendment of the act besides an analysis of current legislation. Grammatical or teleological interpretation of the provisions governing the simplified procedure doesn't bring a satisfactory answer to the question of whether the legislation intended for governing bodies applies on the activity of authorized inspector. Whether through negligence or intent the legislature concerning authorized inspector is conceptual hybrid. In an attempt to clarify its functioning and to define it either a subject of public or private law, concept of simplified procedure deforms to disadvantage of different group of subjects and loses partly its original meaning. The only way out of this confusing situation is amendment of Building Act in favor of unambiquous concept of simplified procedure. The author deals with position of the authorized inspector in initial chapters. The procedure of nomination and assumptions that an applicant must meet...
33

Análise numérica de pilares de aço isolados e inseridos em paredes em situação de incêndio / Numerical analysis of isolated and embedded on walls steel columns under fire situation

Simões, Yagho de Souza 10 April 2018 (has links)
Em um incêndio, pilares de aço inseridos em paredes apresentam uma resposta termoestrutural diferente daqueles isolados, de modo que a compartimentação oferece um aumento de sua resistência ao fogo. Poucos estudos foram desenvolvidos até o presente momento para avaliar o desempenho de pilares em contato com paredes, sendo que aqueles já realizados apresentaram respostas que ainda deixam dúvidas sobre esses elementos. Diante disso, este trabalho propõe analisar, em contexto numérico, o comportamento de pilares de aço isolados e inseridos em paredes sujeitos à ação térmica, a partir do uso do código computacional ABAQUS versão 6.14. A modelagem termoestrutural, considerando a parede somente como elemento de compartimentação, promoveu resultados pouco consistentes, o que leva a concluir que a alvenaria influencia na resposta estrutural de pilares em situação de incêndio. Por essa razão, ao inserir molas que controlam o deslocamento axial das paredes na modelagem numérica, os resultados alcançados passaram a ser mais representativos. Análises complementares a respeito da influência do fator de carga e do nível de rigidez axial e rotacional na resistência ao fogo dos pilares também foram realizadas. Para todos os modelos, constatou-se a influência negativa do fator de carga quando aumentado. Quanto à restrição axial, foi verificado que sua presença possui maior influência na resistência ao fogo em comparação com sua intensidade, uma vez que a elevação desse parâmetro não afetou o tempo crítico dos pilares, para a maior parte dos casos analisados. Em relação à rigidez rotacional, ela se mostrou favorável para a resistência ao fogo. Além do mais, a pesquisa contou com uma avaliação do método simplificado da ABNT NBR 14323:2013 para cálculo da evolução da temperatura em perfis de aço. Concluiu-se que ele apresenta melhores resultados para os pilares com aquecimento uniforme na seção transversal. Por essa razão, foi proposta uma nova metodologia de cálculo de temperatura para pilares em contato com paredes, validada por meio de testes numéricos. / In a fire situation, steel columns embedded on walls demonstrate a different thermo- structural response from those isolated, so that the subdivision offers an increase of its fire resistance. Few studies have been developed in order to evaluate the performance of columns in contact with walls, and those already performed showed results that still leave doubts about these elements. Therefore, this work proposes to analyze, in a numerical context, the behavior of isolated and embedded on walls steel columns in fire using the software ABAQUS 6.14 as a modeling tool. The thermo-structural modeling, considering the wall only as a compartmentation element, has presented poor results, which leads to the conclusion that the masonry has influence on the structural response of columns subjected to fire situation. For this reason, when inserting springs in order to control the axial displacement of the walls in numerical modeling, the obtained results were satisfactory. Further analyzes in respect of the load factor influence and the level of axial and rotational stiffness on the fire resistance of columns were also performed. For all the models, it was verified a negative influence of the load factor when increased. However, when it comes to the axial restriction, it was verified that its presence had more influence in the fire resistance of the structural element despite of its intensity, once the increase of this parameter did not affect the critical time of the columns, for most cases analyzed. In respect to rotational stiffness, it was proven favorable to the fire resistance. In addition, this research employed the simplified method presented in the ABNT NBR 14323: 2013 to calculate the temperature evolution in steel profiles. It was concluded that it presents good results only for the columns with uniform heating in the cross section. For this reason, a new methodology to calculate the temperature of columns in contact with wall was proposed, validated by numerical tests.
34

Development of a Simplified Analysis Approach for Predicting Pile Deflections of Piers Subjected to Lateral Spread Displacements and Application to a Pier Damaged During the 2010 Maule, Chile, M8.8 Earthquake

Palmer, Logan Matthew 01 December 2018 (has links)
The 2010, moment magnitude 8.8 earthquake that occurred near Maule, Chile caused major damages to several piers in the Port of Coronel located approximately 160 kilometers (100 miles) to the South of the earthquake epicenter. One of the piers, the North Pier, experienced significant lateral spreading that was caused from liquefaction of the soils at the approach zone of the pier. Damages from lateral spreading and liquefaction effects consisted of sheet pile welding ruptures of the cross-support beams, stiffener buckling, pile displacements, pile rotations, and pier deck displacement. Researchers analyzed the North Pier after the earthquake and documented in detail the damage caused by lateral spread displacements. This study introduces a simplified performance-based procedure called the "Simplified Modeling Procedure" that is used for the analysis of piles supporting a pier that are exposed to lateral spread displacements. The procedure uses the software LPILE, a common program for analyzing a single pile under lateral loading conditions, to evaluate a more complex multi-pile pier design. Instead of analyzing each of the piles in a given pier individually, the procedure utilizes what is known as a "Super Pile" approach to combine several piles into a single representative pile during the analysis. To ensure displacement compatibility between each "Super Pile" in the analysis, the "Super Piles" are assumed to be fully connected at the top of each "Super Pile" to the pier deck. The Simplified Modeling Procedure is developed and tested using the case study history of the North Pier from the Port of Coronel during the 2010 Maule earthquake. The Simplified Modeling Procedure incorporates p-y springs with a lateral push-over analysis. This approach allows the analysis to be performed in a matter of seconds and allows the user to more easily draw the needed correlations between the rows of piles. This procedure helps identify that different rows of piles either contribute to the movement of the pier or contribute to the bracing of the pier. The procedure ultimately predicts the anticipated pier deck deflection by determining when all the pile rows and their respective shear forces are in equilibrium. The Simplified Modeling Procedure predicted that the North Pier experienced deflections between approximately 0.31 meters (1.01 feet) and 0.38 meters (1.26 feet). The predicted deflections and rotations determined using the procedure were determined to be a relatively close representation of the observations made during the post-earthquake reconnaissance observations.
35

A Novel Experimental Scheme to Fully Separate Permethylated Glycans and Allow Online RP-LC-MS with Simplified ESI-MS Analysis

Hines, Jesse, Tao, Shujuan, Orlando, Ron, Brown, Stacy D. 01 March 2012 (has links)
Abstract available for download.
36

Using Habit Reversal to Decrease Filled Pauses and Nervous Habits in Public Speaking

Mancuso, Carolyn Joanne 11 December 2013 (has links)
ABSTRACT Public speaking is a challenge faced by people from all walks of life. Research in the area of public speaking has focused on examining techniques to reduce public speaking anxiety. Very little research, however, has focused on the acquisition of public speaking skills. While presenting speeches, many people engage in nervous habits that have the potential to decrease the effectiveness of the speech and their credibility as a speaker. This study evaluated the effectiveness of simplified habit reversal in reducing three of these nervous habits: filled pauses, tongue clicking, and inappropriate use of the word like. Following baseline, participants received simplified habit reversal training that consisted of awareness training and competing response training. During post-intervention assessments all 6 participants exhibited an immediate decrease in all three target behaviors.
37

Simplified Sewerage Systems and Potential Application to Rural Louisiana Communities

de Toledo Sobrinho, Homero 01 May 2018 (has links)
Today’s rapid growth in population on sub-urban areas has caused an increase in fecal coliforms to be discharged to down-streams and lakes. The unaffordability of conventional sewerage systems makes it inaccessible to big part of the population of rural communities to receive proper sanitation. Since population growth is only projected to increase during the next few years, action is necessary to change the course of the future of rural communities, more specifically described on this report, Louisiana’s communities. One option to offer affordable sewerage systems to the Louisiana region is that we utilize of the Simplified Sewerage technology. Simplified Sewerage has been tested on several municipalities around the globe, especially in Brazil. The results of its application have proven to be conclusive and beneficial to communities.
38

Advantages and disadvantages with Simplified Technical English : to be used in technical documentation by Swedish export companies

Disborg, Karin January 2007 (has links)
<p>Understanding technical documentation is of vital importance, since instructions and descriptions are given about how technical products are used, maintained and repaired. Because of the increased economic globalization, more and more documentation is both written in English by non-native English writers, and delivered to non-native English readers. More and more documentation is also translated by means of computerized aids. In order to improve comprehension and translatability of technical documentation, controlled languages are created. Controlled languages are subsets of ordinary languages, but with restricted vocabularies and writing rules.</p><p>The aim of this report is to discuss the advantages and disadvantages for Swedish export companies to use Simplified Technical English (STE), which is a controlled language, for their technical documentation. In this work technical writers are asked about their opinions of STE. Additionally, technical texts written in traditional English are compared with versions written in STE, in order to find out whether texts written in a controlled language are easier to read or not. Within the comparison, the differences between the versions are discussed and a readability measurement is done. The measurement showed that readability in technical documentation is improved by using STE. The writers’ opinions are illuminated in three areas, which are: higher documentation quality, reduced translation costs and reduced production costs.</p>
39

Simplifying Reproductive Health in Low-Resource Settings : Access to medical abortion and contraceptive choice, the importance of gendered structures in Rajasthan

Paul, Mandira January 2015 (has links)
India introduced family planning in the ‘50s, legalized abortion in the ‘70s, and accomplished a remarkable drop in maternal mortality and fertility since 1990. Nevertheless, abortions account for a large proportion of maternal deaths, and sterilization is the most frequently used contraception. This thesis aims to identify the means to simplify and increase access to reproductive health in low-resource settings, focusing on abortion and contraception in Rajasthan. A randomized controlled trial compared simplified follow-up, where women assess their abortion outcome at home after early medical abortion, with in-clinic follow-up. Additionally, contraceptive use was compared between study groups post-abortion. In order to explore young women’s opportunities to access reproductive health services in the area, we conducted in-depth interviews with recently-married women. Women in the home-assessment group preferred home-assessment in the future to a greater extent than the women in the clinic follow-up group, who preferred in-clinic follow-up. Complete abortions were reported in 95% of women in the ‘home-assessment group’ and 93% in the ‘in-clinic group’, suggesting that efficacy of simplified follow-up is non-inferior to in-clinic follow-up. A majority (81%) of women carried out the pregnancy test and found it easy to use. Women (96%) were satisfied with their abortion. There were no differences in contraceptive use between study groups at three months; however, women in the ‘in-clinic group’ were most likely to initiate contraception at two weeks. A majority of women preferred the three-month injection, while only 4% preferred sterilization. The recently-married women considered reversible contraception to be unfeasible due to misconceptions and taboos, yet women wanted effective contraception because their current use of traditional methods resulted in unintended pregnancies. Abortions were common, and were procured from private or informal providers. Allowing women to take an active role in reproductive health services can enable simplification of, and access to, reproductive services in low-resource settings as well as in other settings. Simplifying medical abortion, providing contraception ‘intra-abortion’, and offering a context-appropriate and effective means of contraception, creates a great potential to increase access to reproductive health services and can result in a more equal society where women, and men, can attain their sexual and reproductive rights.
40

Stabilité des digues sous chargement sismique : vers une nouvelle génération de méthodes simplifiées / Stability of embankments under seismic loading : towards a new generation of simplified methods

Durand, Capucine 12 July 2018 (has links)
Permettant de protéger les populations des inondations, de canaliser l'eau à des fins d'irrigation ou de production d'électricité, les digues en terre sont des ouvrages stratégiques dont la rupture peut avoir des conséquences dramatiques. La stabilité de ces ouvrages doit ainsi pouvoir être assurée, notamment en cas de séisme. Cependant, étant donné le très grand linéaire qu'ils représentent, la mise en œuvre de vastes campagnes de reconnaissances et de modèles numériques complexes n'est pas toujours envisageable dans les zones de sismicité modérée. L'utilisation d'outils simplifiés, faisant appel à des données facilement mesurables, se révèle indispensable pour fournir une indication sur la stabilité de tronçons de digue soumis à un chargement sismique. Les méthodes simplifiées existantes permettant d'estimer la réponse dynamique des remblais sont inadaptées au contexte des digues. En effet, alors que les digues sont pour la plupart construites dans des vallées sédimentaires, la majorité de ces méthodes, développées pour l’étude des barrages, supposent que l’ouvrage est fondé directement au rocher. Seules deux approches permettent de prendre en compte l’interaction entre l’ouvrage et son sol d’assise (effets de site) : la méthode de Sarma(1979) et celle de Papadimitriou(2014). Cependant, la première est basée sur des hypothèses très fortes (elle considère notamment un rocher rigide et un amortissement uniforme, qui plus est très fort) et la seconde se limite à des ouvrages ayant une hauteur supérieure à 20 si{m}. L'approche développée au cours de cette thèse repose sur des hypothèses plus réalistes, en considérant notamment des géométries adaptées à celles des digues, en prenant en compte les effets de site et en adaptant la dissipation d'énergie au niveau de sollicitation. Une étude paramétrique numérique (calcul de la réponse visco-élastique par éléments spectraux en deux dimensions) est utilisée pour couvrir un ensemble de configurations géométriques et mécaniques de digues. Pour prendre en compte la non-linéarité, les valeurs d'amortissement et de dégradation du module de cisaillement sont adaptées en chaque point des modèles à partir des résultats fournis par une série de calculs en linéaire équivalent 1D. Les réseaux de neurones artificiels, dont l'apprentissage est basé sur les résultats des simulations numériques, sont utilisés pour le développement d'une nouvelle méthode simplifiée. Des abaques sont réalisés, à partir des réseaux de neurones établis, pour offrir une alternative visuelle à leur utilisation "mathématiques". Les outils simplifiés auxquels aboutit cette thèse font appel à des paramètres facilement mesurables sur le terrain. Des méthodes géophysiques sont mises en œuvre au niveau de quatre sites de digues afin d'identifier le meilleur compromis de mesures permettant d'estimer les paramètres nécessaires à l'évaluation de la réponse dynamique de l'ouvrage. / Embankments are strategic facilities that, among other things, protect population from flooding and canalize rivers for energy production or for irrigation concerns. Since their rupture can lead to terrible consequences, they must remain stable, especially in case of earthquake. However, given the very large length of embankments, it is rarely possible to conduct complete investigations and complex numerical models in regions of moderate seismicity. Therefore, simplified tools to estimate the dynamic response of embankments using accessible embankments’ features are necessary to estimate their capacity to resist seismic loadings. Existing simplified methods, generally developed to assess the dynamic response of embankment-dams, turn out to be inappropriate to study the particular case of embankments along rivers – or other types of embankment, with small height and large length. The majority of these simplified methods do not take into account site effects: they assume the presence of rock directly at the base of the embankment, whereas most of large length embankments are located in alluvial valleys. Two methods only - Sarma(1979) and Papadimitriou(2014) - take into account the interaction between the embankment and its soil foundation. However, the first one relies on strong assumptions (among others, that the bedrock is considered rigid and that the viscous damping is supposed to be both spatially uniform and very large) and the second one is limited to tall embankments (higher than 20 si{m}).The method developed in this thesis relies on assumptions that are more realistic: it considers geometries adapted to large length embankments, it accounts for the presence of a soil foundation and includes an energy dissipation process consistent with expected levels of strain. A numerical parametric study is performed based on the computation with the spectral element method of the viscoelastic response of a large set of embankments spanning a wide range of geometrical and mechanical properties. In order to take into account nonlinearity, damping and shear modulus reduction are adapted in each point of the numerical models according to the results of a set of 1D linear equivalent computations. A new simplified method is derived from the obtained numerical results using artificial neural networks. Abacuses are produced from the neural networks so that engineers can have at their disposal a visual tool. This thesis leads to a simplified method that uses some accessible features of embankments as input parameters. The ability of classical geophysical methods to provide those input parameters is further estimated on four sites corresponding to different realistic configurations.

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