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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.
11

Beyond Built Form: The Colosseum

Cetin, Yunus 01 September 2011 (has links) (PDF)
This thesis investigates the Flavian Amphitheatre, better known as the Colosseum, in its relation to setting, symbolic meaning and its afterlife. Crucial to the discussion is the ancient art of memory, through which the Colosseum&rsquo / s ambivalent role as a means of Imperial power is elucidated. Equally important, the buildings&rsquo / iconographic connotations are studied in terms of the architectural orders employed on the fa&ccedil / ade. The Colosseum&rsquo / s extended use and its later emblematic significance comprise the concluding discussion of the thesis.
12

Ammunition Transfer System Optimization Problem

Gunsel, H. Sinem 01 March 2012 (has links) (PDF)
Ammunition Transfer System (ATS) is the electro-mechanical system of the Ammunition Resupply Vehicle (ARV) which will be used to meet T-155 mm Firtina howitzers&rsquo / ammunition demand for tactical requirements of higher firing rate by off-road mobility and survivability. The transfer of ammunitions from ARV to Firtina is to be optimized for an effective improvement of firing rate. In this thesis the transferring order of carried ammunitions is being optimized to minimize the total ammunition transferring time. This transfer problem is modeled as a modification of Travelling Salesman Problem (TSP). The given locations of the ammunitions are treated as cities to be visited and the gripper of ATS is treated as the traveling salesman. By GAMS / the small-size problems are solved optimally but large-size ones get only local optimum. A heuristic algorithm that contains nearest neighbor heuristics as construction method and 2-opt exchange heuristic as improvement method is developed to obtain same or better solutions obtained by GAMS with less computational time.
13

Development Of Indium Tin Oxide (ito) Nanoparticle Incorporated Transparent Conductive Oxide Thin Films

Yavas, Hakan 01 July 2012 (has links) (PDF)
Indium tin oxide (ITO) thin films have been used as transparent electrodes in many technological applications such as display panels, solar cells, touch screens and electrochromic devices. Commercial grade ITO thin films are usually deposited by sputtering. Solution-based coating methods, such as sol-gel however, can be simple and economic alternative method for obtaining oxide films and also ITO. In this thesis, &ldquo / ITO sols&rdquo / and &ldquo / ITO nanoparticle-incorporated hybrid ITO coating sols&rdquo / were prepared using indium chloride (InCl3
14

Numerical Investigation Of The Viscoelastic Fluids

Yapici, Kerim 01 July 2008 (has links) (PDF)
Most materials used in many industries such as plastic, food, pharmaceuticals, electronics, dye, etc. exhibit viscoelastic properties under their processing or flow conditions. Due to the elasticity of such materials, deformation-stress in addition to their hydrodynamic behavior differ from simple Newtonian fluids in many important respects. Rod climbing, siphoning, secondary flows are all common examples to how a viscoelastic fluid can exhibit quite distinctive flow behavior than a Newtonian fluid would do under similar flow conditions. In industrial processes involving flow of viscoelastic materials, understanding complexities associated with the viscoelasticity can lead to both design and development of hydrodynamically efficient processes and to improved quality of the final products. In the present study, the main objective is to develop two dimensional finite volume based convergent numerical algorithm for the simulation of viscoelastic flows using nonlinear differential constitutive equations. The constitutive models adopted are Oldroyd-B, Phan-Thien Tanner (PTT) and White-Metzner models. The semi-implicit method for the pressure-linked equation (SIMPLE) and SIMPLE consistent (SIMPLEC) are used to solve the coupled continuity, momentum and constitutive equations. Extra stress terms in momentum equations are solved by decoupled strategy. The schemes to approximate the convection terms in the momentum equations adopted are first order upwind, hybrid, power-law second order central differences and finally third order quadratic upstream interpolation for convective kinematics QUICK schemes. Upwind and QUICK schemes are used in the constitutive equations for the stresses. Non-uniform collocated grid system is employed to discretize flow geometries. As test cases, three problems are considered: flow in entrance of planar channel, stick-slip and lid driven cavity flow. Detailed investigation of the flow field is carried out in terms of velocity and stress fields. It is found that range of convergence of numerical solutions is very sensitive to the type of rheological model, Reynolds number and polymer contribution of viscosity as well as mesh refinement. Use of White-Metzner constitutive differential model gives smooth, non oscillatory solutions to much higher Weissenberg number than Oldroyd-B and PTT models. Differences between the behavior of Newtonian and viscoelastic fluids for lid-driven cavity, such as the normal stress effects and secondary eddy formations, are highlighted. In addition to the viscoelastic flow simulations, steady incompressible Newtonian flow of lid-driven cavity flow at high Reynolds numbers is also solved by finite volume approach. Effect of the solution procedure of pressure correction equation cycles, which is called inner loop, on the solution is discussesed in detail and results are compared with the available data in literature.
15

Development Of A Computer Program For Friction Winding Systems

Unal, Fuat Gokhan 01 October 2011 (has links) (PDF)
ABSTRACT DEVELOPMENT OF A COMPUTER PROGRAM FOR FRICTION WINDING SYSTEM DESIGN &Uuml / nal, Fuat G&ouml / khan M.Sc., Department of Mining Engineering Supervisor: Prof. Dr. Naci B&ouml / l&uuml / kbasi September 2011, 99 pages As the trend to deeper mines continues, mine hoists and associated equipment will become more sophisticated, complex, large and expensive. Correct selection of the right type of hoist is imperative. In this vital link between underground and surface, crude estimates of hoist capacity are not good enough, and the mining engineer must design and select the right hoisting system to meet the design specifications and establish the most suitable operating parameters. This study aims to constitute a software model, which results all required design parameters of friction type winding system on minimum required power. The computer program has been structured on Microsoft Visual Basic programming language. The program requires user inputs (winding depth, hourly hoisting capacity) and selections (type and number of motors, type of friction wheel mounting) to run macros and equations so that the operating parameters such as skip capacity, rope type and diameter, hoisting speed, acceleration, cycle period, friction wheel diameter are determined to give the minimum motor power requirement.
16

Dehydration Of Aqueous Aprotic Solvent Mixtures By Pervaporation

Sarialp, Gokhan 01 February 2012 (has links) (PDF)
Aprotic solvents are organic solvents which do not easily react with a substance dissolved in it and they do not exchange protons despite of their high ion and polar group dissolving power. Therefore, this characteristic property makes aprotic solvents very suitable intermediates in many industries producing pharmaceuticals, textile auxiliaries, plasticizers, stabilizers, adhesives and ink. Dehydration of these mixtures and recirculation of valuable materials are substantial issues in industrial applications. The conventional method for recovery of aprotic solvents has been distillation, which requires excessive amount of energy to achieve desired recovery. Hydrophilic pervaporation, which is a membrane based dehydration method with low energy consumption, may become an alternative. Because of high dissolving power of aprotic solvents only inorganic membranes can be employed for this application. In this study three types of inorganic membranes (NaA zeolite, optimized silica and HybSi) were employed. Main objective of this studys to investigate effect of membrane type and various operationg parameters (feed composition at a range of 50-5% and temperature at a range of 50-100oC) on pervaporative dehydration of aprotic solvents / dimethylacetamide, dimethylformamide and n-methylpyrrolidone. During the experiments, feed samples were analyzed with Karl Fischer Titration Method / permeate samples were analyzed with Gas Chromatography. Experiments showed that proper dehydration of aqueous aprotic solvent mixtures was succeded with all three membranes investigated. In the target feed water content range (50 to 20%wt), permeate water contents were higher than 98%wt which was quite acceptable for all membranes. Moreover, NaA zeolite membrane performed higher fluxes than optimized silica and HybSi in composition range of 50 to 15% water at 50oC. It was also observed that HybSi membrane had higher fluxes and permeate water contents than optimized silica membrane for all solvents. On the other hand, the rates of decrease in permeate fluxes changed depending on the type of solvent for optimized silica and HybSi membranes. With both membranes, permeate flux of dimethylformamide decreased much slower than that of n-methylpyyrolidone. Furthermore, the results showed that permeate fluxes of HybSi membrane increased with increasing operation temperature due to the change of solvent activity in mixture. In addition, an Arrhenious type equation was used to describe changes in fluxes with changing temperature. It was also found that activation energy of water for diffusion through HybSi membrane was calculated as 8980 cal/mol.
17

Representations of sexual practice and identity in men's prisons since the 1950s in the UK and the US

Riley, Michael J. January 2014 (has links)
In this thesis I propose that the representation of the prison is an untapped and valuable resource for non-traditional representations of the queered male, homo-sex and sexualities. I draw together texts on prison and sexuality from the 1800s to the 2000s in order to discuss the representation of prison in light of what it adds to a wider historical understanding of sexuality. The thesis is broadly chronological in form, analysing academic and theoretical texts in context alongside popular cultural representations. I reassess the ways in which sexuality is viewed and understood over time, and place homosexuality within the framework of wider male sexuality as represented in the prison. I theorise a re-imagining of homosexuality within normative male sexuality and I challenge the concept of ‘situational sex' through the complex issues behind understandings of sex in prison. My research methodology includes close textual analysis of representations of prison in literature, film and television alongside academic and theoretical texts on sexuality, gender and queer theory. Each chapter focuses on specific cultural texts, including Against the Law (1957), Birdman of Alcatraz (1962) Short Eyes (1977), Scum (1977, 1979) and Oz (1997-2003). By drawing the representations and the theories together I am able to provide a re-reading of the texts within a recognition of sexual fluidity and the reclassification of heterosexual males and gender hierarchies. In my research I argue that the representation of sex in prison re-writes sexuality and contributes to a reading of the queering potential of the cultural representation of prison. With this method I challenge conventional understandings of sexuality as well as perceptions of how male sexuality is viewed in popular culture. I argue that the cultural representation of the prison is a site of queer potentiality in form, idea and context and is a means to re-imagine male sexuality.
18

Hallo, Welt! Adolescent angst und das Erwachsenwerden in Marisha Pessls Special Topics in Calamity Physics und Zoe Jennys Das Blütenstaubzimmer

Ludemann, Franziska 01 August 2010 (has links)
Special Topics in Calamity Physics (2006) by Marisha Pessl and Das Blütenstaubzimmer (1997) by Zoё Jenny both feature strong female characters who go through difficult times because they experience genuine disillusionment with regard to their friends, the opposite sex, and, especially, their family. The focus of this thesis was to analyze if the authors depict their characters in such a way that one can see correlations between the emotional behavior of these characters and a phenomenon that is often referred to as adolescent angst. The theoretical foundation for defining adolescent angst and for understanding mechanisms that trigger adolescent angst was provided by Rapoport and Ismond’s internationally appraised DSM-IV Training Guide for Diagnosis of Childhood Disorders (1996) and Reinherz et al.’s ground-breaking study on „Depressive Disorders“ (2006). In my thesis, I was able to show that the depictions of difficult relationships between the protagonists and their parents and friends show characteristics of adolescent angst. Contrary to that, positive influences like reliable friends who are understanding and lend support, function as motivational forces which decrease the protagonists’ anxieties and frustration in both texts. The analysis of the final scenes showed that after all hardships, the protagonists do not give up hope and open themselves up to a once unimaginable future. Although Pessl and Jenny dismiss the concept of a clear didaxis in their texts, they nevertheless imply a motivational message; namely that adolescent angst can be conquered and overcome. I was able to demonstrate that the concept of adolescent angst serves as a catalyst for the development of the protagonists in both Special Topics in Calamity Physics and Das Blütenstaubzimmer . The bestseller status of both novels underlines that the authors’ decision to conclude these novels which are centered around adolescent angst with an open ending seems to cater to a modern young adult readership, especially within the context of pop culture.
19

A Comparative Formal Investigation Of The Bath-gymnasium Complex Plan Type In Roman Asia Minor As A Reflection Of Romanization And Urban Renewal

Dinler, Oya 01 August 2007 (has links) (PDF)
This thesis investigates the formal aspects of the bath-gymnasium complex plan type which was developed in Asia Minor during the Roman era in relation to the development of the the imperial thermae in Rome, the capital city of the Roman Empire. Close resemblances in the architectural configuration of bath-gymnasium complexes and imperial thermae are analyzed in order to provide complementary insight concernin the evolution of Roman bath architecture and bathing tradition. The comparative investigation of the formal aspects of the plan types reveals the contribution of Asia Minor and its role in influencing the architectural developments in the capital. The thesis concentrates on the development of the bath-gymnasium complex plan type in Asia Minor and the imperial thermae in Rome in order to elucidate the outcomes of mutual influence in criss-crossing Greek and Italic features. Crucial to this investigation ,s the understanding of the multiple effects of historical processes such as Hellenization, Romanization and urbanization that were synthesized in the bath architecture of the capital and the provinces. Also, the symbolic, cosmological, and political aspects of Roman bath architecture are highlighted ,n this thesis.
20

Neural Network Prediction Of Tsunami Parameters In The Aegean And Marmara Seas

Erdurmaz, Muammer Sercan 01 July 2004 (has links) (PDF)
Tsunamis are characterized as shallow water waves, with long periods and wavelengths. They occur by a sudden water volume displacement. Earthquake is one of the main reasons of a tsunami development. Historical data for an observation period of 3500 years starting from 1500 B.C. indicates that approximately 100 tsunamis occurred in the seas neighboring Turkey. Historical earthquake and tsunami data were collected and used to develop two artificial neural network models to forecast tsunami characteristics for future occurrences and to estimate the tsunami return period. Artificial Neural Network (ANN) is a system simulating the human brain learning and thinking behavior by experiencing measured or observed data. A set of artificial neural network is used to estimate the future earthquakes that may create a tsunami and their magnitudes. A second set is designed for the estimation of tsunami inundation with relation with the tsunami intensity, the earthquake depth and the earthquake magnitude that are predicted by the first set of neural networks. In the case study, Marmara and Aegean regions are taken into consideration for the estimation process. Return periods including the last occurred earthquake in the Turkish seas, which was the izmit (Kocaeli) Earthquake in 1999, were utilized together with the average earthquake depths calculated for Marmara and Aegean regions for the prediction of the earthquake magnitude that may create a tsunami in the stated regions for various return periods of 1-100 years starting from the year of 2004. The obtained earthquake magnitudes were used together with tsunami intensities and earthquake depth to forecast tsunami wave height at the coast. It is concluded that, Neural Networks predictions were a satisfactory first step to implement earthquake parameters such as depth and magnitude, for the average tsunami height on the shore calculations.

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