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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.
111

Outside The Cage: The Political Campaign To Destroy Mixed Martial Arts

Doeg, Andrew 01 January 2013 (has links)
This is an early history of Mixed Martial Arts in America. It focuses primarily on the political campaign to ban the sport in the 1990s and the repercussions that campaign had on MMA itself. Furthermore, it examines the censorship of music and video games in the 1990s. The central argument of this work is that the political campaign to ban Mixed Martial Arts was part of a larger political movement to censor violent entertainment. Connections are shown in the actions and rhetoric of politicians who attacked music, video games and the Ultimate Fighting Championship on the grounds that it glorified violence. The political pressure exerted on the sport is largely responsible for the eventual success and widespread acceptance of MMA. The pressure forced the sport to regulate itself and transformed it into something more acceptable to mainstream America
112

Consumerism and Christianity: An Analysis and Response from a Christian Perspective

Christman, Amy 09 May 2015 (has links)
No description available.
113

A pre-study of the static behaviour of a single diagonal timber arch bridge

Öhgren, Lovisa, Åström, Malin January 2020 (has links)
The aim of this thesis is to study and gain more insight about the static behaviour of the three hinged single diagonal timber arch bridge in different situations. The bridge was tested for static analyses for both Ultimate Limit State and Serviceability Limit State, to investigate its behaviour and if it is possible to be built at the selected location. Furthermore, the dimensions of the elements are to be determined. Pre-studies on similar bridges have been done and their problems have been taken into account when analysing the behaviour of this bridge. Thereafter, two different designs have been constructed. The finite element software RFEM has been used in this project to be able to analyse the behaviour of the two different models. The in-plane buckling of the arch is the most critical part of the bridge and the bridge should therefore be designed regarding that. Additionally, different alternatives were suggested to reduce the deformation of the deck in the models. Finally, an optimized model is reached which consists of longitudinal beams and has an arch with a wide cross section.
114

Optimum First Failure Loads of Sandwich Plates/Shells and Vibrations of Incompressible Material Plates

Yuan, Lisha 11 March 2021 (has links)
Due to high specific strength and stiffness as well as outstanding energy-absorption characteristics, sandwich structures are extensively used in aircraft, aerospace, automobile, and marine industries. With the objective of finding lightweight blast-resistant sandwich structures for protecting infrastructure, we have found, for a fixed areal mass density, one- or two-core doubly-curved sandwich shell's (plate's) geometries and materials and fiber angles of unidirectional fiber-reinforced face sheets for it to have the maximum first failure load under quasistatic (blast) loads. The analyses employ a third-order shear and normal deformable plate/shell theory (TSNDT), the finite element method (FEM), a stress recovery scheme (SRS), the Tsai-Wu failure criterion and the Nest-Site selection (NeSS) optimization algorithm, and assume the materials to be linearly elastic. For a sandwich shell under the spatially varying static pressure on the top surface, the optimal non-symmetric one-core (two-core) design improves the first failure load by approximately 33% (27%) and 50% (36%) from the corresponding optimal symmetric design with clamped and simply-supported edges, respectively. For a sandwich plate under blast loads, it is found that the optimal one-core design is symmetric about the mid-surface with thick face sheets, and the optimal two-core design has a thin middle face sheet and thick top and bottom face sheets. Furthermore, the transverse shear stresses (in-plane transverse axial stresses) primarily cause the first failure in a core (face sheet). For the computed optimal design under a blast load, we also determined the collapse load by using the progressive failure analysis that degrades all elasticities of the failed material point to very small values. The collapse load of the clamped (simply-supported) sandwich structure is approximately 15%–30% (0%–17%) higher than its first failure load. Incompressible materials such as rubbers, polymers, and soft tissues that can only undergo volume preserving deformations have numerous applications in engineering and biomedical fields. Their vibration characteristics are important for using them as wave reflectors at interfaces with a fiber-reinforced sheet. In this work we have numerically analyzed free vibrations of plates made of a linearly elastic incompressible rubber-like material (Poison's ratio = 0.5) by using a TSNDT for incompressible materials and the mixed FEM. The displacements at nodes of a 9-noded quadrilateral element and the hydrostatic pressure at four interior nodes are taken as unknowns. Computed results are found to match well with the corresponding either analytical or numerical ones obtained with the commercial FE software Abaqus and the 3-dimensional linear elasticity theory. The analysis discerns plate's in-plane vibration modes. It is found that a simply supported plate admits more in-plane modes than the corresponding clamped and clamped-free plates. / Doctor of Philosophy / A simple example of a sandwich structure is a chocolate ice cream bar with the chocolate layer replaced by a stiff plate. Another example is the packaging material used to protect electronics during shipping and handling. The intent is to find the composition and the thickness of the "chocolate layer" so that the ice cream bar will not shatter when dropped on the floor. The objective is met by enforcing the chocolate layer with carbon fibers and then finding fiber materials, their alignment, ice cream or core material, and its thickness to resist anticipated loads with a prescribed level of certainty. Thus, a sandwich structure is usually composed of a soft thick core (e.g., foam) bonded to two relatively stiff thin skins (e.g., made of steel, fiber-reinforced composite) called face sheets. They are lightweight, stiff, and effective in absorbing mechanical energy. Consequently, they are often used in aircraft, aerospace, automobile, and marine industries. The load that causes a point in a structure to fail is called its first failure load, and the load that causes it to either crush or crumble is called the ultimate load. Here, for a fixed areal mass density (mass per unit surface area), we maximize the first failure load of a sandwich shell (plate) under static (dynamic) loads by determining its geometric dimensions, materials and fiber angles in the face sheets, and the number (one or two) of cores. It is found that, for a non-uniformly distributed static pressure applied on the central region of a sandwich shell's top surface, an optimal design that has different materials for the top and the bottom face sheets improves the first failure load by nearly 30%-50% from that of the optimally designed structure with identical face sheets. For the structure optimally designed for the first failure blast load, the ultimate failure load with all of its edges clamped (simply supported) is about 15%-30% (0%-17%) higher than its first failure load. This work should help engineers reduce weight of sandwich structures without sacrificing their integrity and save on materials and cost. Rubberlike materials, polymers, and soft tissues are incompressible since their volume remains constant when they are deformed. Plates made of incompressible materials have a wide range of applications in everyday life, e.g., we hear because of vibrations of the ear drum. Thus, accurately predicting their dynamic behavior is important. A first step usually is determining natural frequencies, i.e., the number of cycles of oscillations per second (e.g., a human heart beats at about 1 cycle/sec) completed by the structure in the absence of any externally applied force. Here, we numerically find natural frequencies and mode shapes of rubber-like material rectangular plates with different supporting conditions at the edges. We employ a plate theory that reduces a 3-dimensional (3-D) problem to a 2-D one and the finite element method. The problem is challenging because the incompressibility constraint requires finding the hydrostatic pressure as a part of the problem solution. We show that the methodology developed here provides results that match well with the corresponding either analytical or numerical solutions of the 3-D linear elasticity equations. The methodology is applicable to analyzing the dynamic response of composite structures with layers of incompressible materials embedded in it.
115

NUMERICAL INVESTIGATION OF CLOSELY SPACED ANCHOR GROUPS UNDER DIFFERENT GEOMETRIC AND LOADING CONDITIONS

Muhammad Fasih ur Rehman (14222801) 17 May 2024 (has links)
<p>  </p> <p>Post-installed bonded anchors find a wide range of application in construction industry due to their versatility and flexibility in accommodating diverse engineering needs. Engineering practices often encounter situations where space constraints within a building member lead to unusual anchor group geometric configurations. Multiple anchor groups with small inter-group spacing (closely spaced anchor groups) emerge as a result. The stress-field and overall behaviour of individual anchor groups is affected by the presence of other closely spaced anchor groups. Situation become more intricate when these closely-spaced anchor groups are installed in close proximity of edge, subjected to different loading conditions and involve different eccentric loading scenarios.</p> <p>The current design standards provide limited and very conservative guidelines for designing and analysing closely spaced anchor groups where spacing between neighbouring anchor groups is less than the critical anchor spacing. This paper presents a 3-dimensional (3D), Finite Element (FE) study on the tension and shear behaviour of closely spaced anchor groups under various geometric and loading conditions. Different parameters such as inter-group spacing, presence of nearby edge and loading positions (eccentricities and symmetry of loading) for models loaded in tension, are numerically investigated. In case of shear loads, anchor groups with similar / different edge distance in the direction of loading and different loading positions are investigated. In this study, concrete cone break-out failure for tension loaded anchor groups and concrete edge failure for shear loaded anchor groups are considered as critical failure modes. </p> <p>Numerical analysis is carried out using microplane model for concrete with relaxed kinematic constraint as the constitutive law. 3D, finite element, Mascroscopic Space Analysis (MASA) program is used to numerically investigate the behavior of closely spaced anchor groups under different geometric and loading conditions. The numerical modelling approach is first verified and validated against available experimental results on anchor groups and then used to carry out a detailed and systematic study. Parametric study on a wide range of geometric configurations containing multiple anchor groups subjected to different loading positions (centric / eccentric) is carried out.</p> <p>Comparison study is conducted to check the numerical resistance capacities against analytical values calculated using existing concrete capacity design (CCD) method incorporating existing reduced embedment depth / edge distance approach and newly developed virtual edge approach. The virtual edge approach considers a virtual edge to assign individual tributary areas to individual anchor groups in calculating the concrete breakout resistance of anchorages. Evaluation of results indicate that virtual edge approach is appropriate, rational and reasonably conservative to consider the influence of presence of neighbouring anchor group on the capacity of given anchorage. A new set of guidelines is recommended to design closely space anchor groups for arbitrary geometric and loading conditions.</p>
116

Vyhodnocení zatěžovacích zkoušek pilot z tryskové injektáže / Evaluation of loading test of jet-grouted piles

Čechová, Simona January 2021 (has links)
The master thesis consists of a theoretical part and a practical part. In the theoretical part jet-grouting technology is described briefly. Mechanical properties of jet-grouted piles were characterized. Various estimation methods of ultimate pile bearing capacity are described in this thesis – analytical calculation of ultimate bearing capacity for bored piles and estimation of ultimate pile bearing capacity by analysis of load-displacement curve defined by CHIN (1970; 1972). Load transfer method for piles and hyperbolic load-transfer curve are introduced. As a part of the load-trasfer method analysis, a method of estimating ultimate pile shaft friction called beta method is defined. In the practical part were evaluated several static load tests of jet-grouted piles and were constructed their load-displacemnt curves. Then reverse analysis of the results from static load tests was performed using load-transfer method. Then ultimate pile bearing capacity was estimated using analytical calculation of pile bearing capacity for bored piles and using analysis of load-displacement curve with method by CHIN (1970; 1972). By evaluation of load transfer method and beta method ultimate shaft resistence for each pile was estimated. Results and load-displacement curves were compared.
117

Determination of an ultimate pit limit utilising fractal modelling to optimise NPV

Yasrebi, Amir Bijan January 2014 (has links)
The speed and complexity of globalisation and reduction of natural resources on the one hand, and interests of large multinational corporations on the other, necessitates proper management of mineral resources and consumption. The need for scientific research and application of new methodologies and approaches to maximise Net Present Value (NPV) within mining operations is essential. In some cases, drill core logging in the field may result in an inadequate level of information and subsequent poor diagnosis of geological phenomenon which may undermine the delineation or separation of mineralised zones. This is because the interpretation of individual loggers is subjective. However, modelling based on logging data is absolutely essential to determine the architecture of an orebody including ore distribution and geomechanical features. For instance, ore grades, density and RQD values are not included in conventional geological models whilst variations in a mineral deposit are an obvious and salient feature. Given the problems mentioned above, a series of new mathematical methods have been developed, based on fractal modelling, which provide a more objective approach. These have been established and tested in a case study of the Kahang Cu-Mo porphyry deposit, central Iran. Recognition of different types of mineralised zone in an ore deposit is important for mine planning. As a result, it is felt that the most important outcome of this thesis is the development of an innovative approach to the delineation of major mineralised (supergene and hypogene) zones from ‘barren’ host rock. This is based on subsurface data and the utilisation of the Concentration-Volume (C-V) fractal model, proposed by Afzal et al. (2011), to optimise a Cu-Mo block model for better determination of an ultimate pit limit. Drawing on this, new approaches, referred to Density–Volume (D–V) and RQD-Volume (RQD-V) fractal modelling, have been developed and used to delineate rock characteristics in terms of density and RQD within the Kahang deposit (Yasrebi et al., 2013b; Yasrebi et al., 2014). From the results of this modelling, the density and RQD populations of rock types from the studied deposit showed a relationship between density and rock quality based on RQD values, which can be used to predict final pit slope. Finally, the study introduces a Present Value-Volume (PV-V) fractal model in order to identify an accurate excavation orientation with respect to economic principals and ore grades of all determined voxels within the obtained ultimate pit limit in order to achieve an earlier pay-back period.
118

台灣上市公司股權結構與資本結構之關聯性研究

高國霖 Unknown Date (has links)
摘 要 本研究以最終控制之觀念與研究方法,分析台灣上市公司股權結構與資本結構間的關係。首先探討台灣上市公司最終控制者的型態,接著以分析研究控制股東的控制權與現金流量請求權之偏離程度對公司舉債的影響。最後,納入集團企業及其組織型態等因素,探討其與偏離程度的關係。 實證結果顯示,不論以10%或20%的投票權作為股權分散的判斷標準,家族皆為最普遍的控制股東型態。當假設控制股東對名目公司(其他機構)的持股比率為0%時,實證結果顯示,若控制權與現金流量請求權偏離程度愈大,則其舉債程度越高。這可能意味著控制股東在其控制權與現金流量請求權的偏離情形下,會透過負債程度的操控來侵佔少數股東的財富,亦可能對債權人甚或納稅義務人的權益產生影響。 在集團企業因素的影響方面,實證結果指出當上市公司屬於集團企業時,其控制權與現金流量請求權之偏離程度較之非集團企業者為大,且集團企業的組織型態越複雜,控制股東之控制權與現金流量請求權的偏離程度將越大,代表控制股東更可能透過金字塔結構及交叉持股的方式來加強對公司的控制,進而產生侵犯少數股東權益的動機。 / Abstract This study investigates if the controlling shareholders of firms in Taiwan expropriate the minority shareholders through raising debt. Two cutoff levels of ultimate control right, 10% and 20%, are applied to find out the fact that the listed companies in Taiwan are not widely held but mostly in the control of families. On top of this fact, the result indicates that the deviation of control rights from cash flow rights of the controlling shareholders has positive effect on the debt ratio. It also reveals that the more the block shareholders’ control rights deviates from cash flow rights, the more the debt corporate would raise. Furthermore, the deviation is larger for conglomerate companies than their counterparties. For conglomerate companies, the deviation is positively related to the complexity of the conglomerate structure.
119

Apport des modèles géo-métallurgiques et de la catégorisation des ressources à la définition de la fosse ultime d'une mine à ciel ouvert : Application à la mine de cuivre de Mantos de la Luna au Chili / Contribution of geo-metallurgical model and resource categorization to the definition of the ultimate open pit mine : Application to Mantos de la Luna copper mine in Chile

Delgado Vega, José Manuel 20 December 2012 (has links)
La nécessité de maximiser la récupération d'une ou plusieurs espèces utiles d'un gisement du cuivre, l´optimisation des consommations d'additifs dans le processus de traitement métallurgique, savoir où laisser les matériaux qui dans le futur pourraient être valorisés par une série de nouvelles opérations etc., conduit à adapter la planification minière aux caractéristiques géologiques et métallurgiques du gisement.Les unités géo-métallurgiques sont déterminées par une combinaison des principaux paramètres géologiques, type de roche, altération, minéralisation, etc. Chaque unité présente un comportement différent au processus de traitement métallurgiques avec des caractéristiques de récupération et de consommation d'acide bien spécifiques.D´une façon générale, on peut définir la planification de la mine comme un outil permettant de faire la liaison entre la géologie et la métallurgie, non seulement selon des paramètres économiques et de teneurs, mais aussi selon des paramètres géologiques et métallurgiques.Pour pouvoir construire le modèle géo-métallurgique ou géo-minier métallurgique (G.M.M) ainsi que mettre en oeuvre la catégorisation des ressources, nous avons utilisé des outils géostatistiquesLe fait de disposer d´un modèle G.M.M est d'une grande aide pour la définition de la fosse finale et la planification à long terme, soit simplement comme une première approche de la réponse du gisement au processus de traitement métallurgique, mais surtout pour optimiser les coûts et définir différentes alternatives pour maximiser la récupération du métal.Cette étude a été appliquée au cas du gisement stratiforme de Cu et Ag de Mantos de la Luna situé dans le Nord du Chili. Il comporte en particulier une comparaison entre l'approche traditionnelle et l'approche qui intègre le concept du modèle G.M.M. qui porte principalement sur les teneurs de coupure. Le concept G.M.M. peut donc influencer les décisions stratégiques comme les décisions opérationnelles. / The present research work concerns the general field of mining project set-up and is aimed at developing a new approach in long term mine planning. The main objective of this work is to incorporate the geo-metallurgical concept to mine planning which is traditionally based only on economic criteria.The need to maximize the recovery of one or more useful elements of a copper deposit, the optimization of reagents consumption in the metallurgical process, to know where to leave the materials which may be valorise in the future by a series of new operations, etc.. lead to fit mine planning and metallurgical geological features of the deposit. The geo-metallurgical units are determined by a combination of the main geological parameters, rock type, weathering, mineralization, etc... Each unit has a different behaviour in metallurgical process with specific values of recovery and acid consumption.The set-up of the geo-metallurgical mining model (GMM) and the resources categorization were made using geostatistical tools.Having a GMM model is a great help for the definition of the ultimate pit and long-term planning, as well as in a first approach of the response of the deposit to metallurgical process, but also to optimize costs and establish alternatives to maximize metal recovery.This work is based on the practical case of the Mantos de la Luna stratabound Cu and Ag deposit located in northern Chile. It proposes a methodology for resources classification of this type of deposit and includes a comparison between the traditional approach and the approach that integrates the concept of the GMM model.
120

Contribution à l’étude du comportement des pieux sous chargements cycliques axiaux / Contribution to the study of the behavior of piles under cyclic axial loading

Benzaria, Omar 14 December 2012 (has links)
Dans le cadre du Projet National SOLCYP, le présent travail avait pour but d'étudier la réponse des pieux sous chargements axiaux pour les phases avant, pendant et après cycles. Pour atteindre cet objectif, une étude expérimentale étendue a donc été réalisée par le moyen de deux compagnes d'essais de chargements cycliques sur différents types de pieux instrumentées (battus, forés, vissés) dans deux sites expérimentaux : le site de Merville dans l'argile surconsolidée des Flandres et le site de Loon-Plage près de Dunkerque dans les sables denses des Flandres. Les essais cycliques comportaient des essais en compression, en traction et alternés avec des séries de cycles à forte amplitude conduisant à la rupture cyclique et des séries d'amplitude modérée à très grands nombres de cycles (N>5 000 cycles).L'interprétation de ces essais a englobé, d'une part, une analyse globale du comportement des pieux sous chargements cycliques notamment (i) la réduction de la capacité du pieu; (ii) le nombre de cycles que le pieu peut support avant la rupture (iii) l'évolution du déplacement en tête des pieux (rigidité cyclique). D'autre part, elle a intégré une étude locale en particulier sur la dégradation du frottement latéral et l'évolution de la résistance de pointe du pieu. Cette thèse, basée sur l'étude expérimentale, a permis la formulation des conclusions pratiques sur le comportement des pieux sous chargements cycliques axiaux et a proposé des perspectives pour bien cerner cette problématique / As part of the French National research project SOLCYP, the purpose of this work was study the behavior of the piles under axial loadings for the phases before, during and after cycles.To achieve this objective, an extensive series of static and cyclic axial pile load tests have been carried out in two experimental sites of the North of France: the overconsolidated Flandrian clays (Merville experimental site) and in dense Flandrian sands (Loon-Plage experimental site). Tests were performed on driven closed-ended pipe piles, bored piles and screwed. All piles were instrumented with retrievable extensometers for measuring the load distribution along the pile wall.Cyclic load tests were composed of series of cycles of constant load amplitude. A large range of load histories were applied including series of small amplitude cycles and great number of cycles (N > 5000) and series of large amplitude cycles leading to cyclic failure after a small number of cycles..A large volume of data has been interpreted to describe the effects of axial cyclic loads on the behavior of the piles. The interpretation of these tests included, on the one hand, a global analysis focusing on (i) the potential reduction on the ultimate axial capacity; (ii) the number of load cycles of a given load that the pile can sustain before cyclic failure and (iii) the evolution of displacements of the pile head during cyclic loading (pile stiffness). In addition, it integrated a local study in particular on shaft friction degradation along the pile wall and evolution of the resistance of point of the pile.This thesis, based on the experimental study, allowed the formulation of the practical conclusions on the behavior of the piles under axial cyclic loadings and proposed prospects for determining these problems well

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