Dissertations / Theses on the topic 'THD ANALYSIS'
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1
Zhang, Di. "Analysis and Design of Paralleled Three-Phase Voltage Source Converters with Interleaving." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/27579.
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Three-phase voltage source converters(VSCs) have become the converter of choice in many ac medium and high power applications due to their many advantages, including low harmonics, high power factor, and high efficiency. Modular VSCs have also been a popular choice as building blocks to achieve even higher power, primarily through converter paralleling. In addition to high power ratings, paralleling converters can also provide system redundancy through the so-called (N+1) configuration for improved availability, as well as allow easy implementation of converter power management. Interleaving can further improve the benefit of paralleling VSCs by reducing system harmonic currents, which potentially can increase system power density. There are many challenges to implement interleaving in paralleled VSCs system due to the complicated relationships in a three-phase power converter system. In addition, to maximize the benefit of interleaving, current knowledge of symmetric interleaving is not enough. More insightful understanding of this PWM technology is necessary before implement interleaving in a real paralleled VSCs system.
In this dissertation, a systematic methodology to analyze and design a paralleled three-phase voltage source converters with interleaving is developed. All the analysis and proposed control methods are investigated with the goal of maximizing the benefit of interleaving based on system requirement.
The dissertation is divided into five sections. Firstly, a complete analysis studying the impact of interleaving on harmonic currents in ac and dc side passive components for paralleled VSCs is presented. The analysis performed considers the effects of modulation index, pulse-width-modulation (PWM) schemes, interleaving angle and displacement angle. Based on the analysis the method to optimize interleaving angle is proposed. Secondly, the control methods for the common mode (CM) circulating current of paralleled three-phase VSCs with discontinuous space-vector modulation (DPWM) and interleaving are proposed. With the control methods, DPWM and interleaving, which is a desirable combination, but not considered possible, can be implemented together. In addition, the total flux of integrated inter-phase inductor to limit circulating current can be minimized. Thirdly, a 15 kW three phase ac-dc rectifier is built with SiC devices. With the technologies presented in this dissertation, the specific power density can be pushed more than 2kW/lb. Fourthly, the converter system with low switching frequency is studied. Special issues such as beat phenomenon and system unbalance due to non-triplen carrier ratio is explained and solved by control methods. Other than that, an improved asymmetric space vector modulation is proposed, which can significantly reduce output current total harmonic distortion (THD) for single and interleaved VSCs system. Finally, the method to protect a system with paralleled VSCs under the occurrence of internal faults is studied. After the internal fault is detected and isolated, the paralleled VSCs system can continue work. So system reliability can be increased.Ph. D.
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Mazumdar, Joy. "System and method for determining harmonic contributions from nonlinear loads in power systems." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/23215.
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The objective of this research is to introduce a neural network based solution for the problem of measuring the actual amount of harmonic current injected into a power network by an individual nonlinear load. Harmonic currents from nonlinear loads propagate through the system and cause harmonic pollution. As a result, voltage at the point of common coupling (PCC) is rarely sinusoidal. The IEEE 519 harmonic standard provides customer and utility harmonic limits and many utilities are now requiring their customers to comply with IEEE 519. Measurements of the customer’s current at the PCC are expected to determine the customer’s compliance with IEEE 519. However, results in this research show that the current measurements at the PCC are not always reliable in that determination. In such a case, it may be necessary to determine what the customer’s true current harmonic distortions would be if the PCC voltage could be a pure sinusoidal voltage. However, establishing a pure sinusoidal voltage at the PCC may not be feasible since that would mean performing utility switching to reduce the system impedance. An alternative approach is to use a neural network that is able to learn the customer’s load admittance. Then, it is possible to predict the customer’s true current harmonic distortions based on mathematically applying a pure sinusoidal voltage to the learned load admittance. The proposed method is called load modeling. Load modeling predicts the true harmonic current that can be attributed to a customer regardless of whether a resonant condition exists on the utility power system. If a corrective action is taken by the customer, another important parameter of interest is the change in the voltage distortion level at the PCC due to the corrective action of the customer. This issue is also addressed by using the dual of the load modeling method. Topologies of the neural networks used in this research include multilayer perceptron neural networks and recurrent neural networks. The theory and implementation of a new neural network topology known as an Echo State Networks is also introduced. The proposed methods are verified on a number of different power electronic test circuits as well as field data. The main advantages of the proposed methods are that only waveforms of voltages and currents are required for their operation and they are applicable to both single and three phase systems. The proposed methods can be integrated into any existing power quality instrument or can be fabricated into a commercial standalone instrument that could be installed in substations of large customer loads, or used as a hand-held clip on instrument.
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Miksl, Jan. "Analýza, vlastnosti a aplikace komerčně dostupných proudových násobiček." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219150.
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The diploma thesis deals with analysis, validation, measurement of parameters of the commercially available current multiplies (namely the EL2082 and EL4083) and their applications in practice. Control analysis are carried out in OrCAD PSpice program and compared with values from datasheets. Control analysis are focused on AC and DC characteristics of these active blocks. There are discusses the input impedance, the output impedance, the current gain and the possibility of electronic adjusting. The parameters of the elements were verified by measurements. Proposals for circuit applications (selective circuit, oscillator, frequency filter) with EL2082 and EL4083 are presented and analyzed in the program OrCAD. Three oscillator circuit designs are experimentally tested and the results are compared with the theoretical expectations and simulations in OrCAD. The possibility of electronic control for oscillators is examined. Also the sensitivity and the tolerance analysis are carried out. The constructional details of oscillators are presented at the end of this work.
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Gould, Matthew. "An economic analysis of the Councils of the United Nations." Thesis, University of Westminster, 2014. https://westminsterresearch.westminster.ac.uk/item/8yqqv/an-economic-analysis-of-the-councils-of-the-united-nations.
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This thesis consists of three pieces of research focussed on the Councils of the United Nations, predominantly the United Nations Security Council (UNSC). We consider three broad questions: which countries typically get on to the UNSC in its current form; which countries ought to get on to the UNSC; and how well might proposed changes to the UNSC steer it towards such ideals. In order to address the latter two questions it is sensible to begin by investigating how the current system works and if there are any particular characteristics which influence the chances of a country being elected to the UNSC. In Chapter 2 we develop a model to test the significance of a country’s characteristics on their probability of election to the UNSC. Chapter 3 then starts by developing a set of theoretical tests which can be applied to council voting systems, such as the selection of UNSC members from the UN General Assembly. The tests score a voting system based on how well the distribution of power in the council meets the power one would expect under a system where country representatives cast their vote in the council based on the outcomes of country or regional-level referendums. We then apply this, using the implied probabilities of election which are a consequence of the results of Chapter 2, to the UNSC election process. We then finish by applying the tests of Chapter 3, which consider how equitable a proposal is, together with a further test of procedural efficiency, to each of the proposed reforms to the UNSC election process.
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Neužil, Jan. "Uživatelské rozhraní pro HP89410A." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-217775.
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The aim of this thesis was to develop user interface in LabVIEW to make typical measurements with spectral analyzer HP89410A There is introduced the theory of operation of an analogue heterodyne and a digital FFT spectral analyzer. It is explained the background of the Fast Fourier Transform. There are discussed the key settings in measuring with FTT analyzer, like window function, bandwidth, number of frequency points, or the averaging. Further is described the program, which was developed for measuring frequency characteristic by white noise and by stepped measurement. It was also made a module for measuring Signal to Noise Ratio and module for Total Harmonic Distortion. In the last part of this thesis are shown the results of processed exemplar measurements.
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Alissa, Arwa. "Islamic mortgages : a comparative study to improve the legal and financial system of mortgages in the Royal Kingdom of Saudi Arabia with a regulatory analysis of the US and UK, and case analyses of the UK, Sharjah, Dubai and Saudi Arabia." Thesis, University of Westminster, 2018. https://westminsterresearch.westminster.ac.uk/item/q8q83/islamic-mortgages-a-comparative-study-to-improve-the-legal-and-financial-system-of-mortgages-in-the-royal-kingdom-of-saudi-arabia-with-a-regulatory-analysis-of-the-us-and-uk-and-case-analyses-of-the.
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This research is the first comprehensive critical evaluation of the ways in which Islamic mortgages can be developed and executed in a Sharia compliant manner in order to boost the development of housing markets primarily in Saudi Arabia, with regulatory analyses of securitisation in the US and EU, and case analyses of the UK, Sharjah, and Dubai. The regulatory analyses of securitization show how the excesses of modern financial legal techniques to greatly expand opportunistic developments of mortgagebacked markets led to market failures, and that such market failure could be avoided by the use of Islamic finance principles. These case analyses have been selected to provide a spectrum of different socio-economic contexts in which to compare the Saudi Arabian system. The study also engages in the examination of the Western and Islamic legal systems and their impact on mortgaging and securitisation theory and practice. Securitisation, namely the activity involving the packaging, dividing and selling of mortgages in the primary market has in recent years become a well-established business process (with banking, financing and legal implications and aspects) for enhancing home financing and home ownership in the USA, the UK and Western Europe, all of which are subject to common law contractual processes. However, it would be natural to suppose that further development of the Saudi Arabian and other Islamic legal systems would include securitisation techniques in the near future. Indeed, certain Islamic finance structures lend themselves to securitisation processes which are investigated in depth in this work. Banking and financial activities in the Islamic countries are however governed by a mix of conventional practice, common law and Islamic law, with variations occurring in the same between different jurisdictions. This study aims to engage in a detailed comparison of the conventional (Western) banking system and the banking procedures and processes followed in Islamic jurisdictions in order to develop and recommend a standardized securitisation system for mortgages, which draws upon the best of western regulations and practices and is yet compliant with Islamic law, i.e. the Sharia. The Western banking system is based upon intermediation between entities that have money and ones that need to use it, the charging of interest and a rational decisionmaking process between banks and their clients. The Islamic system on the other hand is governed by Islamic law, which prohibits interest, speculation and any type of activity that is perceived to be oppressive. It recommends close partnerships between bankers andclients, rather than short-term transactional utility. The establishment of common ground between these two systems is undoubtedly a challenging task, particularly because of the differences in the interpretation of religious law by different clerics. This study however points out that significant common ground can be established if standardisation of legal practices and bank policies can be achieved in Islamic countries. The development of high levels of standardisation will help in the creation of securitisation processes for housing mortgages that are Sharia compliant and thus satisfy two important objectives, namely religious requirements and the expansion of the housing market.
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Sristy, Kiranmayi Venkata. "Analysis of a Turbopiston Pump." ScholarWorks@UNO, 2006. http://scholarworks.uno.edu/td/413.
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An innovative pump, TurboPiston Pump, has been invented to incorporate the merits of centrifugal, axial, and positive displacement pumps. The TurboPiston pump is designed to deliver large flow rates at very high pressure of up to 1000 psia. To improve the original design, an understanding of flow behavior inside the pump is needed. Therefore, this thesis focuses on simulating the flow field inside the pump and studying its performance. This study includes modeling the pump using a commercial CAD package, GAMBIT and a 3-D computational fluid dynamic (CFD) solver, FLUENT. The calculation employs both the simplified steady moving frame and the complicated transient sliding mesh schemes. The flow pattern, static pressure distribution, and total pressure losses are calculated and analyzed. The regions of high total pressure losses and potential creation of cavitation are identified. Design changes are recommended to minimize cavitation and total pressure losses to improve the pump performance.
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Bienvenu, Kirk Jr. "Underwater Acoustic Signal Analysis Toolkit." ScholarWorks@UNO, 2017. https://scholarworks.uno.edu/td/2398.
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This project started early in the summer of 2016 when it became evident there was a need for an effective and efficient signal analysis toolkit for the Littoral Acoustic Demonstration Center Gulf Ecological Monitoring and Modeling (LADC-GEMM) Research Consortium. LADC-GEMM collected underwater acoustic data in the northern Gulf of Mexico during the summer of 2015 using Environmental Acoustic Recording Systems (EARS) buoys. Much of the visualization of data was handled through short scripts and executed through terminal commands, each time requiring the data to be loaded into memory and parameters to be fed through arguments. The vision was to develop a graphical user interface (GUI) that would increase the productivity of manual signal analysis. It has been expanded to make several calculations autonomously for cataloging and meta data storage of whale clicks. Over the last year and a half, a working prototype has been developed with MathWorks matrix laboratory (MATLAB), an integrated development environment (IDE). The prototype is now very modular and can accept new tools relatively quickly when development is completed. The program has been named Banshee, as the mythical creatures are known to “wail”. This paper outlines the functionality of the GUI, explains the benefits of frequency analysis, the physical models that facilitate these analytics, and the mathematics performed to achieve these models.
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Baklanova, Viktoria. "Money market funds in the US and the EU : a legal and comparative analysis." Thesis, University of Westminster, 2012. https://westminsterresearch.westminster.ac.uk/item/8z40w/money-market-funds-in-the-us-and-the-eu-a-legal-and-comparative-analysis.
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The failure of the Reserve Primary Fund, a US money market fund, in September 2008 triggered a widespread withdrawal of assets from other money market funds in the US. The withdrawals led the US Government to adopt emergency measures to maintain market stability. The ability of money market funds to rapidly withdraw funding from the financial system also showed during the European sovereign debt crisis in the summer of 2011. The crisis prompted further regulatory debate on both sides of the Atlantic on how to make money market funds more resilient to investors’ runs and systemic shocks. The solutions that are currently discussed propose to eliminate the essential bank-like feature of money market funds – their ability to transact at a stable share price – and thereby reduce their attractiveness to investors seeking cash management options outside the banking system. This thesis detaches from those discussions originally enquiring on how should money market funds be regulated in the US and in the EU. As a theoretical premise, this research identifies two overarching goals for money market funds regulation, namely, investor protection and systemic stability. The prevalent proposals for regulation are thus seen as misguided because the change in money market funds pricing mechanisms and the accounting convention would demonstrably not satisfy these goals. In order to formulate the new propositions for the regulation of money market funds in the US and the EU, therefore, this thesis first critically evaluates the existing US and EU regulatory frameworks applicable to money market funds from the standpoint of the dual policy goal of investor protection and systemic stability. Secondly, it introduces an alternative path for achieving this dual goal. It is argued that the blueprint of the international money market fund regulation ought to focus on full disclosure of the funds’ assets and liabilities – portfolio holdings and fund investors – as the primary measure of investor protection. Such disclosure also addresses systemic stability concerns by empowering regulators to properly monitor the transmission channels of funding risk. While my study does not purport to do away with risk limiting rules for money market funds, it cautions against copying the US-centric view of the investment standards to the much shallower European markets under the banners of harmonisation. Instead, this thesis advocates a harmonised international approach to the transparency of money market fund activities and the creation of a global database of market 5 exposures that would subject asset managers to public scrutiny and enable regulators to monitor the major risk transmitting channels. By these means the dual regulatory goal in money market fund regulation – investor protection and systemic stability – shall be upheld.
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Vestrelli, Francesco. "Study on membrane contactors performances analysis, system simulations and fields of application /." Online version, 2006. http://dds.crl.edu/CRLdelivery.asp?tid=12327.
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Neupane, Nirdesh. "Comparison of Switched Reluctance Motor and Double Stator Switched Reluctance Motor." ScholarWorks@UNO, 2018. https://scholarworks.uno.edu/td/2564.
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This thesis is concerned with the design and analysis of Switched Reluctance Motor (SRM) and its improved structure Double Stator Switched Reluctance Motor (DSSRM). Three configurations of SRM viz. Inner Stator, Outer stator and Double Stator are designed and simulated in ANSYS Maxwell Suite. Design parameters are chosen by aiming optimum performance of motor after literature review and analytical study of the motor. SRM is not a line start machine, so power converter circuit is required to excite the motor. Without proper switching of current, desired torque is not obtained in SRM. The converter circuit and switching unit is built in Maxwell Circuit Editor Tools. Both magnetostatics and transient analysis is performed to investigate motion torque, torque ripple, normal force and radial force. A good comprehensive comparison of three different types of SRMs based on their torque profile and force densities is presented. Simulation performed verified better performance of DSSRM.
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Shi, Lifang. "Luminescent Quantum dots for Cellular Analysis." ScholarWorks@UNO, 2007. http://scholarworks.uno.edu/td/597.
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Luminescent quantum dots have attracted great interest in recent years among biological researchers since they provide solutions to problems associated with use of organic fluorophores in cellular studies. Quantum dots show high photostability, high emission quantum yield, narrow and symmetric emission peaks and size-dependent wavelength tunability. The objective of my PhD studies was to develop CdSe/ZnS quantum dot-based probes and utilize them in cellular assays. The first phase of the work was to develop luminescent quantum dot fluorescence resonance energy transfer (FRET) based probes for protease activity. The probes were based on FRET interactions between quantum dots that serve as donors and rhodamine molecular acceptors that were immobilized to the surface of the quantum dots through peptide linkers, which contained selective enzymatic cleavage sites. Upon enzymatic cleavage of the peptide linkers, the rhodamine molecules no longer provided an efficient energy transfer channel to the quantum dots, which brightened the previously quenched quantum dots. The probes were applied to detect enzyme activity, screen enzyme inhibitors, and discriminate between normal and cancerous cells primarily because of the difference in the proteolytic activity in extracellular matrices. The second phase of my work was to take advantage of FRET and quantum dots to develop pH sensor. First quantum dots were modified with metallothionein (MT) to be water-soluble and biocompatible. The MT-coated quantum dots were labeled with Rhodamine through the formation of amide bonds with å-amine group of lysine in MT peptide to form the probes. FRET efficiency between quantum dots (donor) and rhodamine (acceptor) was pH dependent. The final phase of my studies focused on the first preparation of reversible quantum dot-based cellular probes for labile iron. The MT coated quantum dots was modified with EDTA to form probes. When captured by the EDTA molecules, iron ions quenched the emission of quantum dots. Removal of iron from the quantum dot surface by free EDTA or other iron chelators with higher binding affinity resulted in a rise in the luminescence of quantum dots. The analytical properties of the probes including sensitivity, selectivity, and reversibility were characterized. Intracellular assays in iron-enriched astrocytes will be carried out.
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Clay, Robert Henry. "The Making and Analysis of Covered." ScholarWorks@UNO, 2009. http://scholarworks.uno.edu/td/937.
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This paper thoroughly examines the production of the thesis film, Covered. Writing, production design, cinematography, editing, sound, technology, workflow, and direction are discussed with attention to how each uniquely contributed to the story. In an effort to objectively critique the finished film, feedback from test audiences will be examined.
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Stormo, Jeremy M. "Analysis of Windows 8 Registry Artifacts." ScholarWorks@UNO, 2013. http://scholarworks.uno.edu/td/1779.
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Microsoft’s series of Windows operating systems represents some of the most commonly encountered technologies in the field of digital forensics. It is then fair to say that Microsoft’s design decisions greatly affect forensic efforts. Because of this, it is exceptionally important for the forensics community to keep abreast of new developments in the Windows product line. With each new release, the Windows operating system may present investigators with significant new artifacts to explore. Described by some as the heart of the Windows operating system, the Windows registry has been proven to contain many of these forensically interesting artifacts. Given the weight of Microsoft’s influence on digital forensics and the role of the registry within Windows operating systems, this thesis delves into the Windows 8 registry in the hopes of developing new Windows forensics utilities.
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Ratul, Saiful A. "Optimal DG Placement: A Multimethod Analysis." ScholarWorks@UNO, 2016. http://scholarworks.uno.edu/td/2269.
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With Power System being restructured in the vision of Smart Grid, it is important now more than ever to find suitable locations to place Distributed Generators (DG). Distributed generators, which may be renewable, are not limited to specific locations as in the case of conventional generators. Several papers have been published that make suggestions on where the optimal location of DG should be in a system. Objectives ranging from loss minimization to total cost minimization have been the factor for such studies. In this study, a new method is introduced that hopes to improve a current system in three ways by maximizing load, minimizing the locational marginal price and improving line contingency scenarios. The proposed methodology is simulated using MATPOWER’s Optimal Power Flow on the IEEE 14 bus test system.
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Nallagula, Sandeep. "Behavior and Flexure Analysis of Balsa Wood Core Sandwich Composites: Experimental, Analytical and Finite Element Approaches." ScholarWorks@UNO, 2006. http://scholarworks.uno.edu/td/371.
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The load-deflection behavior of a US Army Corps of Engineers available sandwich plates in three-point bending with glass phenolic facings and balsa wood core is being investigated under room and elevated temperatures. Test data on bending rigidity, critical interfacial failure (skin-to-core interface) and shear stress are collected and analyzed. The load-deflection curves plots up to the point of failure initiation are being studied. The effects of the span and the radius of the loading nose on the bending modulus and strength are examined systematically. Theoretical calculations from a modified beam theory of sandwich structure are applied and the effect of the shearing rigidity of the core is studied, and the propensity with respect to the span is also investigated. A finite element model is developed to study the flexural and stress analysis. Based on the results, this thesis proposes a desirable analytical approach that correlates theory with experiment as defined below.
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Huang, Zhongwei. "Three essays on the monitoring role of financial analysts." Thesis, Cergy-Pontoise, Ecole supérieure des sciences économiques et commerciales, 2015. http://www.theses.fr/2015ESEC0002.
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Cette thèse est composée de trois chapitres présentant le rôle et pouvoir de surveillance des analystes financiers sous trois perspectives différentes. Le premier chapitre est consacré au pouvoir de surveillance des analystes financiers sur le reporting financier. Plus précisément, j’étudie le contenu informatif et le pouvoir de surveillance des commentaires écrits par les analystes financiers sur la qualité des résultats comptables. Je mets en évidence que ces commentaires ont un effet marginal prédictif en ce qui concerne les retraitements comptables futurs et a un contenu informatif pour les investisseurs qui va au-delà des prévisions de résultat, de l’estimation du prix des actions, du cours cible, et des autres informations qualitatives contenues dans les rapports des analystes financiers. Les analyses complémentaires suggèrent que les réactions de marché suite à ces commentaires sont principalement induites par les commentaires négatifs et ceux traduisant un caractère certain. Par ailleurs, je trouve que les entreprises réduisent considérablement le niveau de leurs accruals discrétionnaires suite à la publication de commentaires négatifs, cette réduction n’est pas associée à une hausse de la manipulation des résultats financiers résultant d’actions réelles. Le deuxième s’intéresse aux questions suivantes : Est-ce que les analystes financiers ont un pouvoir de surveillance sur le reporting financier permettant de résoudre les problèmes d’agence liés à l’augmentation non justifiée des rémunérations des cadres dirigeants résultant de manipulations comptables. Je mets en avant que le pouvoir de surveillance des analystes financiers réduit les possibilités pour les cadres dirigeants de dissimuler aux administrateurs les manipulations comptables réalisées, permettant ainsi aux administrateurs d’ajuster plus facilement les rémunérations des cadres dirigeants le cas échéant. En accord avec cet argument, je trouve que les résultats comptables publiés sont moins prépondérants dans la détermination de la rémunération du PDG d’entreprises critiquées par les analystes financiers pour la faible qualité de leurs résultats comptables, mais seulement lorsque les administrateurs sont susceptibles d’être au courant de l’existence de rapports critiques. Les principaux résultats sont robustes lorsque les firmes sont appariées par performance et en contrôlant pour les effets fixes entreprises. Ces résultats ne sont pas induits par d’autres éléments textuels contenus dans les rapports d’analystes financiers. Des analyses complémentaires suggèrent que l’importance accordée aux résultats comptables diminue lorsque le montant des accruals s’écarte de la prévision des analystes. Le troisième s’intéresse aux effets des réformes réglementaires visant à accroître l’indépendance des analystes financiers sur le pouvoir de surveillance des analystes sur le reporting financier. La règle NASD 2711 exige des entreprises de courtage une séparation au niveau de leur structure entre leurs activités de banque d’investissement et celles de recherche sur les titres; dans le même temps, le Global Settlement demande aux banques participantes de financer les entreprises de recherche indépendantes à hauteur de 432,5 millions de dollars sur la période 2004 – 2009. Les résultats suggèrent une augmentation de l’efficience du pouvoir de surveillance des analystes financiers suite à l’introduction de ces réformes. Les analyses complémentaires mettent en avant que cette hausse est principalement induite par le Global Settlement. La robustesse des résultats est testée par l’utilisation de la méthode difference-in-difference utilisant des entreprises canadiennes comme groupe de contrôle. De plus, je mets en évidence un revirement de situation en ce qui concerne l’efficience du pouvoir de surveillance des analystes financiers suite à l’achèvement de la période de financement obligatoire de cinq années requise par le Global SettlementThis dissertation consists of three chapters that present three standalone essays on the monitoring role of financial analysts. Chapter 1 investigates the monitoring role of financial analysts in the financial reporting process by examining the informativeness and monitoring effect of their written comments on earnings quality. I find that these comments have incremental predictability with respect to future accounting restatements, and convey information to investors beyond that in the earnings forecasts, stock ratings, price targets, and other qualitative text in analyst reports. Further analyses suggest that the market’s reaction to these comments is primarily driven by negative comments and comments written with certainty. In addition, controlling for accrual reversals, I find that firms significantly reduce the level of accruals-based earnings management after receiving negative comments, and this reduction is not accompanied by an increase in real activities management. Overall, the first chapter provides direct evidence on analysts’ monitoring role in financial reporting. Chapter 2 examines whether and how analysts’ monitoring of the financial reporting process alleviates a well-known agency problem in which a manager inflates her compensation by manipulating earnings. I argue that analysts’ monitoring reduces a manager’s ability to conceal earnings management from directors, thus facilitating directors’ adjustment of executive compensation in the presence of earnings management. Consistent with this argument, I find that earnings carry a lower weight in the determination of CEO compensation in firms that are criticized by analysts regarding earnings quality, but only when directors are likely to be aware of the critical analyst reports. The main findings are robust to matching on performance and controlling for firm-fixed effects and are not driven by other text in the analyst reports. Additional analyses suggest that the weight placed on earnings decreases as the actual accruals deviate from analysts’ accruals forecasts. Overall, the second chapter emphasizes analysts’ monitoring role in alleviating managerial rent extraction in executive compensation. Chapter 3 provides evidence on the impact of recent analyst independence reforms (the National Association of Securities Dealers [NASD] Rule 2711 and the companion New York Stock Exchange [NYSE] Rule 472 Amendment, and the Global Settlement) on analysts’ monitoring role in the financial reporting process. The NASD Rule 2711 requires brokerage firms to structurally separate investment banking from equity research; meanwhile, the Global Settlement mandates the participating banks to fund independent research firms to the amount of $432.5 million from 2004 to 2009. I find evidence consistent with an increase in analysts’ monitoring effectiveness following the reforms. Further analyses suggest that this increase is primarily driven by the Global Settlement, rather than by the adoption of NASD Rule 2711. The evidence is robust to a difference-in-difference specification with Canadian firms as the control group. Moreover, I document a reversal of the increase in monitoring effectiveness following the end of the Global Settlement’s five-year funding. Overall, the third chapter highlights the interaction between the monitoring role of financial analysts and the regulatory environment
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Figueirinhas, Diogo. "On the Properties of Gevreyand Ultra-analytic Spaces." Thesis, Linnéuniversitetet, Institutionen för matematik (MA), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-55596.
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We look at the algebraic properties of Gevrey, analytic and ultraanalytic function spaces, namely their closure under composition, division and inversion. We show that both Gevrey and ultra-analytic spaces, G s with 1 ≤ s < ∞ and 0 < s < 1 respectively, form algebras. Closure under composition, division and inversion is shown to hold for the Gevrey case. For the ultra-analytic case we show it is not closed under composition. We also show that if a function is in G s , with 0 < s < 1 on a compact set, then it is in G s everywhere.
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Schwartz, Adam. "The Making and Analysis of For Justin." ScholarWorks@UNO, 2008. http://scholarworks.uno.edu/td/883.
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This paper thoroughly examines the production of the thesis film, For Justin. Each area of the film's production is discussed and analyzed, including the writing, directing, production design, cinematography, editing, sound, and workflow. My decisions in these areas will be discussed at length and ultimately the final film will be analyzed in order to determine whether I achieved my goal of challenging myself to create a heartfelt, touching film with high production values for my twin brother, Justin.
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Silewicz, Bret. "Comparative Analysis of Marine Structural End Connections." ScholarWorks@UNO, 2009. http://scholarworks.uno.edu/td/1015.
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Numerous structural end connections are utilized everyday in the marine industry for ship design and/or maintenance. End connection design has been developed in earlier vessel designs and adapted as a general standard for all vessels being designed / built at a facility. Usually the supporting calculations developed to analyze the structural end connection are not available for engineers to re-examine. Furthermore, young engineers employ un-proven end connections in their designs, using the justification “It has been done like this in the past, it should work.†In this thesis, the author concentrates on finite element analysis for thirteen typical end connections used in the marine industry and correlated the shear and moment transfer to an AISC developed empirical beam equation for comparison. The author will rely on first principle equations and finite element analysis to prove the efficiency of various end connections, and draw comparative conclusions per each end connection analyzed.
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Thakur, Neha S. "Forensic Analysis of WhatsApp on Android Smartphones." ScholarWorks@UNO, 2013. http://scholarworks.uno.edu/td/1706.
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Android forensics has evolved over time offering significant opportunities and exciting challenges. On one hand, being an open source platform Android is giving developers the freedom to contribute to the rapid growth of the Android market whereas on the other hand Android users may not be aware of the security and privacy implications of installing these applications on their phones. Users may assume that a password-locked device protects their personal information, but applications may retain private information on devices, in ways that users might not anticipate. In this thesis we will be concentrating on one such application called 'WhatsApp', a popular social networking application. We will be forming an outline on how forensic investigators can extract useful information from WhatsApp and from similar applications installed on an Android platform. Our area of focus is extraction and analysis of application user data from non-volatile external storage and the volatile memory (RAM) of an Android device.
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McCulley, Shane. "Forensic Analysis of G Suite Collaborative Protocols." ScholarWorks@UNO, 2017. http://scholarworks.uno.edu/td/2386.
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Widespread adoption of cloud services is fundamentally changing the way IT services are delivered and how data is stored. Current forensic tools and techniques have been slow to adapt to new challenges and demands of collecting and analyzing cloud artifacts. Traditional methods focusing only on client data collection are incomplete, as the client may have only a (partial) snapshot and misses cloud-native artifacts that may contain valuable historical information.
In this work, we demonstrate the importance of recovering and analyzing cloud-native artifacts using G Suite as a case study. We develop a tool that extracts and processes the history of Google Documents and Google Slides by reverse engineering the web applications private protocol. Combined with previous work that has focused on API-based acquisition of cloud drives, this presents a more complete solution to cloud forensics, and is generalizable to any cloud service that maintains a detailed log of revisions.
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Joyce, Anne-Marie. "Analysis of Metallurgically Bonded Electrospark Deposited Coatings." ScholarWorks@UNO, 2019. https://scholarworks.uno.edu/td/2670.
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Holland, Michael. "An Assessment of the U.S. Army Corps of Engineers' Environmental Plan Evaluation Methods." ScholarWorks@UNO, 2011. http://scholarworks.uno.edu/td/124.
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The U.S. Army Corps of Engineers is a federal agency with a mission to develop water resource projects to benefit the nation. Some of its large scale projects have been built to benefit cities, but through unintended consequences have caused economic and environmental damages. For example, its control of Mississippi River flooding has protected the City of New Orleans, but contributed to land loss in coastal Louisiana, and by some accounts, made the population more susceptible to hurricane damage. The agency has now embarked on a mission to restore some of the damaged environmental areas. This dissertation evaluates whether policies and practices used by the agency to evaluate and select plans to implement is logically flawed and could produce suboptimal project selection. The primary issue is the practice of including only implementation costs in the analysis while excluding other positive and negative economic impacts. A case study is performed using the method to evaluate a traditional economic development project for which optimal project selection has already been determined using widely accepted benefit-cost practices. The results show that the Corps' environmental project evaluation method would cause rejection of the most efficient plan. The loss of welfare that would result from using this technique is measured by comparing the welfare gain of the optimal project to the welfare gain of the suboptimal projects which could be selected using the flawed methodology. In addition, the dissertation evaluates whether suboptimal results could be produced using two other current Corps policies: selecting projects based on production efficiency, and the exclusion of environmental benefits from the discounting process. For the first policy, a simple counter example shows how clearly inferior choices may come from including only supply considerations in investment choices. For the second policy, it is demonstrated mathematically that refraining from discounting benefits while discounting costs causes a bias towards selection of plans that take longer to build, are delayed in their implantation, or a combination of the two.
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Togiti, Santosh. "Comparative Analysis of Load Flow Techniques for Steady State Loading Margin and Voltage Stability Improvement of Power Systems." ScholarWorks@UNO, 2015. http://scholarworks.uno.edu/td/2042.
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Installation of reactive compensators is widely used for improving power system voltage stability. Reactive compensation also improves the system loading margin resulting in more stable and reliable operation. The improvements in system performance are highly dependent on the location where the reactive compensation is placed in the system. This paper compares three load flow analysis methods - PV curve analysis, QV sensitivity analysis, and Continuation Load Flow - in identifying system weak buses for placing reactive compensation. The methods are applied to three IEEE test systems, including modified IEEE 14-bus system, IEEE 30-bus system, and IEEE 57-bus system. Locations of reactive compensation and corresponding improvements in loading margin and voltages in each test system obtained by the three methods are compared. The author also analyzes the test systems to locate the optimal placement of reactive compensation that yields the maximum loading margin. The results when compared with brute force placement of reactive compensation show the relationship between effectiveness of the three methods and topology of the test systems.
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Ali-Gombe, Aisha Ibrahim. "Malware Analysis and Privacy Policy Enforcement Techniques for Android Applications." ScholarWorks@UNO, 2017. http://scholarworks.uno.edu/td/2290.
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The rapid increase in mobile malware and deployment of over-privileged applications over the years has been of great concern to the security community. Encroaching on user’s privacy, mobile applications (apps) increasingly exploit various sensitive data on mobile devices. The information gathered by these applications is sufficient to uniquely and accurately profile users and can cause tremendous personal and financial damage.
On Android specifically, the security and privacy holes in the operating system and framework code has created a whole new dynamic for malware and privacy exploitation. This research work seeks to develop novel analysis techniques that monitor Android applications for possible unwanted behaviors and then suggest various ways to deal with the privacy leaks associated with them.
Current state-of-the-art static malware analysis techniques on Android-focused mainly on detecting known variants without factoring any kind of software obfuscation. The dynamic analysis systems, on the other hand, are heavily dependent on extending the Android OS and/or runtime virtual machine. These methodologies often tied the system to a single Android version and/or kernel making it very difficult to port to a new device. In privacy, accesses to the database system’s objects are not controlled by any security check beyond overly-broad read/write permissions. This flawed model exposes the database contents to abuse by privacy-agnostic apps and malware. This research addresses the problems above in three ways.
First, we developed a novel static analysis technique that fingerprints known malware based on three-level similarity matching. It scores similarity as a function of normalized opcode sequences found in sensitive functional modules and application permission requests. Our system has an improved detection ratio over current research tools and top COTS anti-virus products while maintaining a high level of resiliency to both simple and complex obfuscation.
Next, we augment the signature-related weaknesses of our static classifier with a hybrid analysis system which incorporates bytecode instrumentation and dynamic runtime monitoring to examine unknown malware samples. Using the concept of Aspect-oriented programming, this technique involves recompiling security checking code into an unknown binary for data flow analysis, resource abuse tracing, and analytics of other suspicious behaviors. Our system logs all the intercepted activities dynamically at runtime without the need for building custom kernels.
Finally, we designed a user-level privacy policy enforcement system that gives users more control over their personal data saved in the SQLite database. Using bytecode weaving for query re-writing and enforcing access control, our system forces new policies at the schema, column, and entity levels of databases without rooting or voiding device warranty.
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Cannon, Melinda. "Comorbid Anxiety and Depression: Do they Cluster as Distinct Groups in Youth?" ScholarWorks@UNO, 2005. http://scholarworks.uno.edu/td/287.
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One of the most common pairs of co-occurring psychological disorders in children and adolescents is anxiety and depression. This high frequency of co-occurrence has led to research examining the structure of anxiety and depression, specifically the shared and unique aspects of these syndromes. The tripartite model accounts for the overlap between the disorders by suggesting that they are related because they share the feature of negative affect or general psychological distress. The model further proposes that they can be differentiated by their unique features of physiological hyperarousal (anxiety) and low positive affect (depression). Factor analytic research has shown that anxious symptoms and depressive symptoms can be structurally distinguished and research on the tripartite model has suggested their conceptual distinction. However, research has not shown that anxiety and depression cluster as distinct symptoms in samples of youth. The current study used cluster analysis to examine the grouping of individuals based on their levels of anxiety and depression. It was hypothesized that four groups would emerge-- anxiety only, depression only, comorbid anxiety and depression, and low/no symptoms. Further analyses using the tripartite model variables provided support of the accurate classification of individuals and this model was shown to be a useful tool in differentiating anxious symptoms from depressive symptoms. Exploratory analyses regarding developmental differences in the structure of anxiety and depression provided mixed support.
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Brown, Michael Ewart. "Reactions in the solid state." Link to this resource, 2005. http://eprints.ru.ac.za/252/.
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Thesis (D.Sc. (Chemistry)) - Rhodes University, 2006.[Appendix]. Dedication - Acknowledgements - Curriculum vitae - Biographical notes - Publication list - Introduction to my research - Commentary-books - Commentary-research papers - Conclusions.
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Brown, Michael Ewart. "Reactions in the solid state." Thesis, Rhodes University, 2006. http://hdl.handle.net/10962/d1015762.
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I have chosen the title for this thesis, "Reactions in the Solid State", for two reasons: Firstly, it is broad enough to cover all of my areas of research, which have been: • Effects of irradiation on solids (PhD topic) • Silver refining (while at the Chamber of Mines) • Kinetics of decomposition of solids (with Dr A.K. Galwey and various others) • Techniques of thermal analysis • Pyrotechnic delay systems (with support from AECI Explosives) • Thermal and photostability of drugs (with Prof B.D. Glass) and, secondly, it was the title of the very successful book co-authored by Drs Andrew Galwey, David Dollimore and me. A large part of my research has been involved in the writing and editing of books, so these are covered in a separate commentary, while commentary on the more than 100 papers to which I have contributed forms the main part of this compilation. It is hoped that the electronic format will enable ready access of to all aspects of my research, including electronic versions of the original papers. The reader will need a copy of Adobe Acrobat Reader to access these.
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Zhao, Zhiyu. "Robust and Efficient Algorithms for Protein 3-D Structure Alignment and Genome Sequence Comparison." ScholarWorks@UNO, 2008. http://scholarworks.uno.edu/td/851.
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Sequence analysis and structure analysis are two of the fundamental areas of bioinformatics research. This dissertation discusses, specifically, protein structure related problems including protein structure alignment and query, and genome sequence related problems including haplotype reconstruction and genome rearrangement. It first presents an algorithm for pairwise protein structure alignment that is tested with structures from the Protein Data Bank (PDB). In many cases it outperforms two other well-known algorithms, DaliLite and CE. The preliminary algorithm is a graph-theory based approach, which uses the concept of \stars" to reduce the complexity of clique-finding algorithms. The algorithm is then improved by introducing \double-center stars" in the graph and applying a self-learning strategy. The updated algorithm is tested with a much larger set of protein structures and shown to be an improvement in accuracy, especially in cases of weak similarity. A protein structure query algorithm is designed to search for similar structures in the PDB, using the improved alignment algorithm. It is compared with SSM and shows better performance with lower maximum and average Q-score for missing proteins. An interesting problem dealing with the calculation of the diameter of a 3-D sequence of points arose and its connection to the sublinear time computation is discussed. The diameter calculation of a 3-D sequence is approximated by a series of sublinear time deterministic, zero-error and bounded-error randomized algorithms and we have obtained a series of separations about the power of sublinear time computations. This dissertation also discusses two genome sequence related problems. A probabilistic model is proposed for reconstructing haplotypes from SNP matrices with incomplete and inconsistent errors. The experiments with simulated data show both high accuracy and speed, conforming to the theoretically provable e ciency and accuracy of the algorithm. Finally, a genome rearrangement problem is studied. The concept of non-breaking similarity is introduced. Approximating the exemplar non-breaking similarity to factor n1..f is proven to be NP-hard. Interestingly, for several practical cases, several polynomial time algorithms are presented.
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Sylve, Joseph T. "Towards Real-Time Volatile Memory Forensics: Frameworks, Methods, and Analysis." ScholarWorks@UNO, 2017. http://scholarworks.uno.edu/td/2359.
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Memory forensics (or memory analysis) is a relatively new approach to digital forensics that deals exclusively with the acquisition and analysis of volatile system memory. Because each function performed by an operating system must utilize system memory, analysis of this memory can often lead to a treasure trove of useful information for forensic analysts and incident responders. Today’s forensic investigators are often subject to large case backlogs, and incident responders must be able to quickly identify the source and cause of security breaches. In both these cases time is a critical factor. Unfortunately, today’s memory analysis tools can take many minutes or even hours to perform even simple analysis tasks. This problem will only become more prevalent as RAM prices continue to drop and systems with very large amounts of RAM become more common. Due to the volatile nature of data resident in system RAM it is also desirable for investigators to be able to access non-volatile copies of system RAM that may exist on a device’s hard drive. Such copies are often created by operating systems when a system is being suspended and placed into a power safe mode.
This dissertation presents work on improving the speed of memory analysis and the access to non-volatile copies of system RAM. Specifically, we propose a novel memory analysis framework that can provide access to valuable artifacts orders of magnitude faster than existing tools. We also propose two new analysis techniques that can provide faster and more resilient access to important forensic artifacts. Further, we present the first analysis of the hibernation file format used in modern versions of Windows. This work allows access to evidence in non-volatile copies of system RAM that were not previously able to be analyzed. Finally, we propose future enhancements to our memory analysis framework that should address limitations with the current design. Taken together, this dissertation represents substantial work towards advancing the field of memory forensics.
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Baumgartner, Richard. "Multipitch Analysis and Tracking for Automatic Music Transcription." ScholarWorks@UNO, 2004. http://scholarworks.uno.edu/td/84.
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Music has always played a large role in human life. The technology behind the art has progressed and grown over time in many areas, for instance the instruments themselves, the recording equipment used in studios, and the reproduction through digital signal processing. One facet of music that has seen very little attention over time is the ability to transcribe audio files into musical notation. In this thesis, a method of multipitch analysis is used to track multiple simultaneous notes through time in an audio music file. The analysis method is based on autocorrelation and a specialized peak pruning method to identify only the fundamental frequencies present at any single moment in the sequence. A sliding Hamming window is used to step through the input sound file and track through time. Results show the tracking of nontrivial musical patterns over two octaves in range and varying tempos.
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Gomez, John-Paul. "Critical Discourse Analysis of Sexual Enhancement Medication Ads." ScholarWorks@UNO, 2004. http://scholarworks.uno.edu/td/179.
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This study contributes to the expanding critical range of discourse analysis by analyzing texts used to market Viagra and other "sexual enhancement medication," pharmaceuticals that treat "erectile dysfunction". Applying elements of Norman Fairclough's critical discourse analysis framework, this study examines as cultural artifacts Viagra, Levitra, and Cialis print advertisements and television commercials and it offers insight into the institutional discourse of "sexual enhancement medication" and how this discourse constructs male identity and subjectivity.
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Viloria, Ysabel. "Sensitivity Analysis of the UNO Activated Sludge Model." ScholarWorks@UNO, 2007. http://scholarworks.uno.edu/td/540.
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Different types of mathematical models have been proposed to predict the activated sludge process final effluent quality. La Motta (2004b) developed a mathematical model linking the operating parameters of an activated sludge system and the classical limiting flux sludge settling theory. This project studies the estimation of the unknown parameters of La Motta's model and also the model's sensibility. To obtain unknown parameters true values Full Information Maximum Likelihood (FIML) estimator is used, it will converge on a set of values that satisfy all the estimating equation simultaneously. Favorable results were obtained when correlations are applied between predicted values using estimated kinetics parameters and the observed values obtained from activated sludge pilot plant located within installations of the Marrero Wastewater Treatment Plant, New Orleans, Louisiana. Constructive results about the sensibility of the model are also obtained demonstrated that the model is affected significantly to the variation of some kinetics parameters.
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Kent, Jason A. "Numerical and Experimental Analysis of a TurboPiston Pump." ScholarWorks@UNO, 2010. http://scholarworks.uno.edu/td/1189.
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The TurboPiston Pump was invented to make use of merits such as, high flow rates often seen in centrifugal pumps and high pressures associated with positive displacement pumps. The objective of this study is to manufacture a plastic model 12†TurboPiston Pump to demonstrate the working principle and a metal prototype for performance testing. In addition, this research includes the study of the discharge valve to estimate the valve closing time and fluid mass being recycled back into the cylinder through hand calculations. Furthermore, a transient simulation was performed in CFD using Fluent to provide a better estimate of what will happen in the actual pump while running. Additionally, an experimental rig was designed to investigate the performance of the first generation valve on the TurboPiston Pump known as the flapper valve. Means to improve the hydrodynamic performance of both valves have been identified for future study.
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Ghimire, Sushma. "Analysis of Fault location methods on transmission lines." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1800.
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Analysis of different types of fault is an important and complex task in a power system. Accurate fault analysis requires models that determine fault distances in a transmission line. The mathematical models accurately capture behavior of different types of faults and location in a timely manner, and prevents damaging power system from fault energy. The purpose of this thesis is to use two methods for determining fault locations and their distance to the reference end buses connected by the faulted transmission line. The two methods used in this investigation are referred to as impedance-based and traveling wave methods. To analyze both methods, various types of faults were modeled and simulated at various locations on a two-bus transmission system using EMTP program. Application and usefulness of each method is identified and presented in the thesis. It is found that Impedance-based methods are easier and more widely used than traveling-wave methods.
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Zanco, Philip. "Analysis of Optimization Methods in Multisteerable Filter Design." ScholarWorks@UNO, 2016. http://scholarworks.uno.edu/td/2227.
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The purpose of this thesis is to study and investigate a practical and efficient implementation of corner orientation detection using multisteerable filters. First, practical theory involved in applying multisteerable filters for corner orientation estimation is presented. Methods to improve the efficiency with which multisteerable corner filters are applied to images are investigated and presented. Prior research in this area presented an optimization equation for determining the best match of corner orientations in images; however, little research has been done on optimization techniques to solve this equation. Optimization techniques to find the maximum response of a similarity function to determine how similar a corner feature is to a multioriented corner template are also explored and compared in this research.
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Senthivel, Saranyan. "Automatic Forensic Analysis of PCCC Network Traffic Log." ScholarWorks@UNO, 2017. http://scholarworks.uno.edu/td/2394.
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Most SCADA devices have a few built-in self-defence mechanisms and tend to implicitly trust communications received over the network. Therefore, monitoring and forensic analysis of network traffic is a critical prerequisite for building an effective defense around SCADA units. In this thesis work, We provide a comprehensive forensic analysis of network traffic generated by the PCCC(Programmable Controller Communication Commands) protocol and present a prototype tool capable of extracting both updates to programmable logic and crucial configuration information. The results of our analysis shows that more than 30 files are transferred to/from the PLC when downloading/uplloading a ladder logic program using RSLogix programming software including configuration and data files. Interestingly, when RSLogix compiles a ladder-logic program, it does not create any lo-level representation of a ladder-logic file. However the low-level ladder logic is present and can be extracted from the network traffic log using our prototype tool. the tool extracts SMTP configuration from the network log and parses it to obtain email addresses, username and password. The network log contains password in plain text.
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Marrero, Robert L. Jr. "Analysis of Variable Insensitive Friction Stir Welding Parameters." ScholarWorks@UNO, 2017. http://scholarworks.uno.edu/td/2385.
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Friction Stir Welding (FSW) was used to perform a Design of Experiment (DOE) to determine the welding parameters effects on yielding consistent mechanical properties across the length of the weld. The travel speed was varied across set forge force and RPM conditions, to find a dataset that will yield consistent mechanical properties independent of the travel speed. Six different welds were completed on two different aluminum panels, the advancing side being Aluminum alloy 2195-T8 at a thickness of .350”, with the retreating side being Aluminum alloy 2219-T851 with a gauge thickness of .360”. A Left-hand Right-hand self-reacting pin tool was used for each weld. The mechanical properties of interest are the Ultimate Tensile Strength, Yield Strength, Elasticity and Hardness. The strengths were evaluated by tensile testing, with the Elasticity being measure post break. Specimens were then polished where macrograph and micrograph analysis was completed. Micro-hardness testing was then completed on the weld nuggets.
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Bovey, D. "The artist biopic : a historical analysis of narrative cinema, 1934-2010." Thesis, University of Westminster, 2015. https://westminsterresearch.westminster.ac.uk/item/9w77z/the-artist-biopic-a-historical-analysis-of-narrative-cinema-1934-2010.
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The thesis provides an historical overview of the artist biopic that has emerged as a distinct sub-genre of the biopic as a whole, totalling some ninety films from Europe and America alone since the first talking artist biopic in 1934. Their making usually reflects a determination on the part of the director or star to see the artist as an alter-ego. Many of them were adaptations of successful literary works, which tempted financial backers by having a ready-made audience based on a pre-established reputation. The sub-genre’s development is explored via the grouping of films with associated themes and the use of case studies. These examples can then be used as models for exploring similar sets of data from other countries and time periods. The specific topics chosen for discussion include the representation of a single painter, for example, Vincent Van Gogh, to see how the treatment of an artist varies across several countries and over seventy years. British artist biopics are analysed as a case study in relation to the idea of them posing as a national stereotype. Topics within sex and gender studies are highlighted in analysis of the representation of the female artist and the queer artist as well as artists who have lived together as couples. A number of well-known gallery artists have become directors of artist biopics and their films are considered to see what particular insights a professional working artist can bring to the portrayal of artistic genius and creation. In the concluding part of the thesis it is argued that the artist biopic overall has survived the bad press which some individual productions have received and can even be said to have matured under the influence of directors producing a quality product for the art house, festival and avant-garde distribution circuits. As a genre it has proved extremely adaptable and has reflected the changing attitudes towards art and artists within the wider community. It has both encouraged renewed interest in the work of established national artists and also raised the profile of those relatively obscure such as Séraphine de Senlis and Pirosmani.
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Orme, Wesley John. "Cross sections used to elucidate differences in wavelet transforms of ground force reactions." [Boise, Idaho] : Boise State University, 2009. http://scholarworks.boisestate.edu/td/70/.
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Smith, Jason. "Solvability characterizations of Pell like equations." [Boise, Idaho] : Boise State University, 2009. http://scholarworks.boisestate.edu/td/55/.
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Yilmaz, S. "The EU & players' agents : a theoretical analysis of the EU's intervention into the regulation of players' agents in Europe." Thesis, University of Westminster, 2015. https://westminsterresearch.westminster.ac.uk/item/9yxq7/the-eu-players-agents-a-theoretical-analysis-of-the-eu-s-intervention-into-the-regulation-of-players-agents-in-europe.
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This research investigates the EU's intervention into the regulation of players' agents, as a policy issue, in the context of EU sports policy. A socio-cultural perspective is developed through analyzing the EU policy actors of the socio-cultural advocacy coalition (the Education and Culture DG within the Commission, the Committee on Culture and Education in the European Parliament and the Member States) operating within the EU sports policy subsystem. The research conceptualizes the socio-cultural regulation of sport as the EU policy actors’ strongly held policy core beliefs. In order to deduce policy core beliefs, there are three research dimensions examined in relation to the regulation of players' agents: coordinated activity between the actors, selective perception by policy core beliefs, and the actors' preference with regards to policy instruments to regulate players agents at European level. This research utilizes the advocacy coalition framework (ACF) as the theoretical framework. Primary documentary sources of the EU are analyzed through the method of content analysis. The EU policy actors have gradually coordinated their activities with regards to the regulation of players’ agents. During the preparatory phase of the White Paper on Sport, there was a weak level of coordination involving interactions and information exchange. During the aftermath of the White Paper on Sport, the actors fostered a stronger coordination through developing and implementing a common plan of action. At the same time, the actors learned about the problems within the activities of players’ agents which they perceived as a threat to their policy core beliefs. As a result, the EU policy actors developed their policy position in relation to players’ agents. In this context, their policy core beliefs performed selective perception by selecting, interpreting and ignoring certain stimuli in order to support that policy position. Consequently, the EU actors agreed on the necessity of a more effective regulatory framework governing players’ agents, yet the EU’s constitutional limitations have constrained potential available options at European level, in particular the emergence of European legal initiative. The research evidences that the EU policy actors’ policy core beliefs have been the main driver for their activities, perceptions and preferences related to players agents.
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Bredemeier, Kristin. "An analysis of the correlation among fashion newspaper coverage and public relations in the United Kingdom." Thesis, University of Westminster, 2010. https://westminsterresearch.westminster.ac.uk/item/904x2/an-analysis-of-the-correlation-among-fashion-newspaper-coverage-and-public-relations-in-the-united-kingdom.
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This study examines the relationship between fashion PR and fashion coverage in UK newspapers and suggests that such coverage is overwhelmingly generated by PR, to the extent that little if any independent fashion journalism actually exists. Despite the fact that existing research on news sources has pointed to the rising influence of PR on media content, the connection between fashion PR and journalism remains unstudied and overlooked. However, the amount of fashion content within UK newspapers has grown significantly over the past two decades, and now occupies a significant amount of space, extending well beyond fashion pages and supplements. This thesis uses empirical evidence to shed light upon the largely closed world of fashion PR and its relationship with fashion journalism. Quantitative and qualitative research methods have been used in order to explore the original hypothesis. They include content analysis of a cross section of UK newspapers during 2004; semi-structured interviews in 2005/06 with fashion PR professionals, fashion journalists and fashion industry insiders; as well as participant observation within a fashion PR agency in 2005. The author’s personal experience within fashion PR and fashion journalism has played a key role in developing insights into a trading relationship which both parties have traditionally had difficulty discussing. The research has found that fashion journalism recycles large amounts of PR material, usually with few checks or criticisms. Newspapers in general do not fund original, i.e. non-PR based, fashion research. Thus, supplying ready-made copy to the fashion press, PR acts as the main provider of access to the latest collections, sample clothes, interviews with designers, celebrities and ‘approved gossip’, hence exerting massive leverage over journalists. Fashion journalists on the other hand remain the gate-keepers as they decide which fashion company ultimately gets coverage. Therefore arguably their main responsibility lies within choosing amongst PR sources as well as when and how to use those. However it has to be noted that even then their power is circumscribed as they cannot ignore some fashion PR. As a result this thesis claims that, despite a limited role in selecting material, fashion journalism is journalism in name only and that it exhibits few if any of the other characteristics that are traditionally ascribed to the profession. This research has found that despite increased amounts of coverage fashion does not rank highly within the hierarchies of UK newspapers and is of limited importance in terms of traditional news values. Arguably this is why it is often overlooked in studies of journalism and print media. However it does attract large advertising budgets and is thus given pre-booked editorial space. This makes it an important area within UK newspapers, which with its lifestyle rather than news focus operates independently of the news desk. The fact that the largely female fashion department is not as closely overseen by the largely male editorial staff as other areas of newspapers allows room for maximum PR activity. One of this thesis's contributions to knowledge derives from its critical examination of this under-examined area within the news media. Fashion PR is also overlooked in the more limited scholarly research into the PR industry, which tends to privilege political or corporate communication. Consequently another contribution to knowledge arises from the way in which this thesis critically examines this important PR sector and explores the nature of its work. One aspect of this is the use of celebrities within fashion PR, demonstrating that this is ubiquitous and more prominent than in any other comparative sector. This study further claims that PR plays an important part in the manufacturing and maintenance of celebrities for the purpose of fashion promotion. However the principal contribution to knowledge derives from the examination of how these two disciplines - fashion journalism and PR - relate to each other. This often furtive relationship has hitherto eluded academic study, arguably due to an underlying conspiracy of silence as well as the informal nature of their relationship. The research has identified contemporary fashion PR as a multifaceted cultural phenomenon with vast economical power that forms the crucial connecting link between the fashion industry and fashion journalism – and hence the wider public, extending its authority into various directions. The overall aim of this study is to contribute to the restricted literature on the topic by providing a sound base towards the creation of a symbiotic relationship between the disciplines of fashion PR and fashion journalism.
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Grealish, Annmarie. "The development of the Youth Empowerment Scale." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/the-development-of-the-youth-empowerment-scale(89eacd8b-691f-4f28-aca8-068c5882595f).html.
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This study developed and validated the Youth Empowerment Scale (YES) for young people with psychosis. This PhD thesis consisted of four phases. Phase 1 conceptualised empowerment from the perspective of young people with psychosis. Phase 1 qualitative findings informed the development of the measurement of empowerment; the Youth empowerment Scale (YES). Phase 2 developed and validated the YES in a non-clinical population. Phase 3 explored the relationship between psychological processes (self-efficacy, control, coping, thinking style, and social support), empowerment, mental health wellbeing and recovery. The YES was then validated again in phase 4 on a clinical population, young people within Child and Adolescents Mental Health Services (CAMHS). This study confirmed that the YES is a valid and reliable measure of empowerment which can be used in future work identifying and supporting empowerment for young people with psychosis.
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Chavez, Arreola Arturo. "Mechanical analysis of a virtual Ganz periacetabular osteotomy in patients suffering hip malformations by using finite element analysis." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/mechanical-analysis-of-a-virtual-ganz-periacetabular-osteotomy-in-patients-suffering-hip-malformations-by-using-finite-element-analysis(7abe47ac-4a7f-48c7-b338-d44ff328e1f7).html.
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Developmental dysplasia of the hip (DDH) refers to some hip disorders, from mildly dysplastic to hip joint dislocation. The main feature of DDH is the deficient acetabular coverage, which is related to a small contact area in the hip joint, and causes an increase in contact pressure. Ganz periacetabular osteotomy (PAO) is a surgical procedure to correct acetabular orientation in DDH. It changes the position of the acetabulum to increase the femoral head coverage and distribute the contact pressure over the cartilage surface. The procedure of Ganz PAO is technically demanding and its success depends significantly on the surgeon’s experience. The aim of this research is to investigate whether it is possible to optimize the position of the acetabular fragment in patients suffering DDH before a Ganz PAO by using finite element (FE) analysis. Using computed tomography (CT) data from patients with DDH, five three-dimensional (3D) hip models were developed. A virtual Ganz PAO was then performed on the hip models. FE analyses were carried out on the hip models before and after virtual Ganz PAO. Contact area, contact pressure and Von Mises stress in the hip cartilage were checked and analysed in order to find an optimal acetabular position. The first virtual surgery performed was only to rotate the acetabular fragment in the lateral direction to improve the acetabular coverage. Analyses were conducted under loading conditions associated with four commonly daily activities: one leg stance, normal walking, descending stairs and knee bend. Second virtual surgery performed was to rotate the fragment in both the lateral and anterior directions and FE analysis conducted for one leg stance loading condition. Contact area, contact pressure and Von Mises stress in the cartilage all varied according to the change of the acetabular fragment position through virtual Ganz PAO. The optimal lateral position of the acetabular fragment occurs close to the inferior border of its normal range. Large anterior position of the acetabular fragment results in large contact area, low contact pressure and Von Mises stress. However, an overcorrection of the acetabular fragment, especially in the anterior correction, leads to problems in performing normal hip movements. The optimal anterior position of the acetabular fragment is therefore close to the superior limit of the normal range. In conclusion, the present analysis shows that an optimal position of the acetabular fragment for patients suffering DDH which improves the acetabular femoral head coverage in the normal range, maximizes the contact area and minimizes the contact pressure and Von Mises stress can be established using 3D models and FE analysis. This information will be useful to the surgeons for the planning of PAO.
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Russell, Justin. "The Structure of Child and Adolescent Aggression: Confirmatory Factor Analysis of a Brief Peer Conflict Scale." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1892.
Full textAbstract:
The importance of simultaneous consideration of forms and functions in youth measures of aggressive behavior is well established. Competing models have presented these highly interrelated constructs as either independent (e.g., reactive or overt) or paired factors (e.g., reactive and overt). The current study examines these models in the context of assessing the viability of a new self-report measure, the Peer Conflict Scale – 20 Item Version. Confirmatory factor analyses were conducted on PCS 20 responses from 1,048 school-age youth living in the Gulf Coast region. Both models significantly improved upon one or two-factor alternatives, and demonstrated partial invariance across gender and grade. The models showed comparable levels of fit to the data, though some loadings for the independent factors model were non-significant. Results encourage use of the PCS 20 across research settings and developmental contexts, while also demonstrating the viability of a paired factors model of aggression.
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Zhao, Zhiyu. "Clustering of Leukemia Patients via Gene Expression Data Analysis." ScholarWorks@UNO, 2006. http://scholarworks.uno.edu/td/1054.
Full textAbstract:
This thesis attempts to cluster some leukemia patients described by gene expression data, and discover the most discriminating a few genes that are responsible for the clustering. A combined approach of Principal Direction Divisive Partitioning and bisect K-means algorithms is applied to the clustering of the selected leukemia dataset, and both unsupervised and supervised methods are considered in order to get the optimal results. As shown by the experimental results and the predefined reference, the combination of PDDP and bisect K-means successfully clusters the leukemia patients, and efficiently discovers some significant genes that can serve as the discriminator of the clustering. The combined approach works well on the automatic clustering of leukemia patients depending merely on the gene expression information, and it has great potential on solving similar problems. The discovered a few genes may provide very important information for the diagnosis of the disease of leukemia.
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Shoemake, Danielle. "Dynamic Behavioral Analysis of Malicious Software with Norman Sandbox." ScholarWorks@UNO, 2010. http://scholarworks.uno.edu/td/1233.
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Current signature-based Anti-Virus (AV) detection approaches take, on average, two weeks from discovery to definition update release to AV users. In addition, these signatures get stale quickly: AV products miss between 25%-80% of new malicious software within a week of not updating. This thesis researches and develops a detection/classification mechanism for malicious software through statistical analysis of dynamic malware behavior. Several characteristics for each behavior type were stored and analyzed such as function DLL names, function parameters, exception thread ids, exception opcodes, pages accessed during faults, port numbers, connection types, and IP addresses. Behavioral data was collected via Norman Sandbox for storage and analysis. We proposed to find which statistical measures and metrics can be collected for use in the detection and classification of malware. We conclude that our logging and cataloging procedure is a potentially viable method in creating behavior-based malicious software detection and classification mechanisms.
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Munukuntla, Sowmya. "Sensitivity Analysis of Synchronous Generators for Real-Time Simulation." ScholarWorks@UNO, 2016. http://scholarworks.uno.edu/td/2172.
Full textAbstract:
The purpose of this thesis is to validate generator models for dynamic studies of power systems using PSS/E (Power System Simulator for Engineering), EMTP (ElectroMagnetic Transient Program), and Hypersim. To thoroughly evaluate the behavior of a power system in the three specified software packages, it is necessary to have an accurate model for the power system, especially the generator which is of interest. The effect of generator modeling on system response under normal conditions and under faulted conditions is investigated in this work. A methodology based on sensitivity analysis of generator model parameters is proposed aiming to homogenize the behavior of the same power system that is modeled in three software packages. Standard IEEE 14-Bus system is used as a test case for this investigation. Necessary changes in the exciter parameters are made using the proposed methodology so that the system behaves identical across all three software platforms.