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2009

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Thermomechanical Modeling And Optimization Of Friction Stir Welding, Manthan Malde Jan 2009

Thermomechanical Modeling And Optimization Of Friction Stir Welding, Manthan Malde

LSU Master's Theses

This thesis research implemented an existing thermomechanical model of friction stir welding process, and studied the surrogate model-based optimization approach to obtain optimal process parameters for the modeled friction stir welding process. As an initial step, the thermomechanical model developed by Zhu and Chao for friction stir welding of 304L stainless steel was replicated using ANSYS. The developed model was then used to conduct parametric studies to understand the effect of various input parameters like total rate of heat input, welding speed and clamping location on temperature distribution and residual stress in the workpiece. With the data from the simulated …

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Comparison Of Helical Tomotherapy And Mixed Beam Treatment Plans For Superficial Head And Neck Cancers, Olivier C. Blasi Jan 2009

Comparison Of Helical Tomotherapy And Mixed Beam Treatment Plans For Superficial Head And Neck Cancers, Olivier C. Blasi

LSU Master's Theses

Purpose: To compare helical tomotherapy (HT) with mixed beam therapy (electron and IMRT) plans for superficial parotid gland and nasal cavity tumors. Methods: Mixed beam and HT dose plans were developed for five patients with superficial tumors (planning target volume or PTV < 5.5 cm depth), three with parotid gland tumors and two with nasal cavity tumors. Seven mixed beam plans included a 5 or 7-field photon IMRT plan optimized on top of a single en-face 16 or 20 MeV electron beam dose distribution. The ratio of photon to electron beam weights (at depth R100) were 1:0 (IMRT only), 2:1, 1:1, 1:2, 1:3, 1:4, and 0:1 (electrons only). Planning objectives for HT plans were set as closely as possible to those in the mixed beam plans, and were determined using our clinical planning protocol for head and neck cancers. The resulting dose distribution from each plan was evaluated using dose-volume quantities, tumor control probability (TCP), normal tissue complication probability (NTCP), and a clinical evaluation by a radiation oncologist. Results: In general, the HT plans showed better target coverage and dose homogeneity index (DHI) than the mixed beam plans. For the parotid patients, the DHI improved an average of 0.056 and 0.035 for the nasal cavity patients compared to the mixed beam plan. TCP was comparable in all patients. NTCP for the mixed beam plan was generally lower or comparable to HT with the largest improvements seen in the contralateral parotid, eye, and lens. Also, the mixed beam plans yielded more favorable PTV and normal tissue results for a single shallow uniform PTV using a heavier weighted electron to IMRT ratio (1:3 or 1:4 ratio of electron to IMRT). Conclusions: The study showed that while HT plans had better target coverage and dose homogeneity, the mixed beam plans (electron and IMRT) had comparable tumor control probability and have the potential for improving NTCP for distal normal tissue for superficial uniform PTVs.

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Typewriters Typing Typist: A Performance History, Sarah Kathryn Jackson Jan 2009

Typewriters Typing Typist: A Performance History, Sarah Kathryn Jackson

LSU Master's Theses

This study contributes to the ongoing exploration of the multiple ways visual and material artifacts perform. I take a look at how typewriters or rather how two representations of typewriters perform. I focus on two different images of working women, each rendered in terms of a popular female stereotype of the period. I selected the images because they bookend a period of time in which typewriters emerged to the fore as an efficient tool of reproduction in the business world. In turn, two different perspectives on the relationship between the typist and her typewriter, woman and machine, are provided. The …

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Your Land Is My Land: Exploring Land Policy In Tangerang, Indonesia Using Kingdon's Multiple Streams Model, Milla Budiarto Jan 2009

Your Land Is My Land: Exploring Land Policy In Tangerang, Indonesia Using Kingdon's Multiple Streams Model, Milla Budiarto

LSU Master's Theses

Indonesia is the world’s largest archipelagic country comprised of over 17, 000 islands with more than 300 ethnic groups and more than 250 different ethnic languages spoken. Due to its land mass size and multifaceted culture, land policy in this country has been ineffective and inadequate in addressing some of the land affairs. One of the indicators of effective land policy is land tenure security, where land dispute incidence is a function of it. Given that the government has very minimal guarantee for land tenure security in this nation, land disputes are inevitable and very common. By the end of …

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Applying The Isotope Pairing Technique To Evaluate How Water Temperature And Habitat Type Influence Denitrification Estimates In Breton Sound, Louisiana, Peter L. Lenaker Jan 2009

Applying The Isotope Pairing Technique To Evaluate How Water Temperature And Habitat Type Influence Denitrification Estimates In Breton Sound, Louisiana, Peter L. Lenaker

LSU Master's Theses

The upper Breton Sound estuary was hydrologically reconnected to the Mississippi River via the Caernarvon freshwater diversion structure in 1991. The Caernarvon structure can provide controlled freshwater pulses to the upper Breton Sound estuarine ecosystem, replicating historic freshwater pulsed events, although the original authorization was to control salinity isohalines at specific locations in the estuary. However, unlike historic freshwater pulsed events prior to the construction of levees, the current freshwater pulse contains an unprecedented amount of inorganic nitrogen, predominately as nitrate (annual average 71.4 µM NO3-). Denitrification is a microbial process, which can potentially remove excess nitrate entering coastal Louisiana …

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Personalized Noninvasive Imaging Of Volumetric Cardiac Electrophysiology, Linwei Wang Jan 2009

Personalized Noninvasive Imaging Of Volumetric Cardiac Electrophysiology, Linwei Wang

Theses

Three-dimensionally distributed electrical functioning is the trigger of mechanical contraction of the heart. Disturbance of this electrical flow is known to predispose to mechanical catastrophe but, due to its amenability to certain intervention techniques, a detailed understanding of subject-specific cardiac electrophysiological conditions is of great medical interest. In current clinical practice, body surface potential recording is the standard tool for diagnosing cardiac electrical dysfunctions. However, successful treatments normally require invasive catheter mapping for a more detailed observation of these dysfunctions. In this dissertation, we take a system approach to pursue personalized noninvasive imaging of volumetric cardiac electrophysiology. Under the guidance …

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Perfection In Paul: Snapshot Of A Stand-Off, Kent Yinger Jan 2009

Perfection In Paul: Snapshot Of A Stand-Off, Kent Yinger

Faculty Publications - Portland Seminary

Following a review of scholarship on ‘perfection’ in Pauline soteriology, this paper will document the current stand-off among Pauline scholars as to whether Paul requires (or thinks Jewish soteriology requires) perfect Law-keeping -- often connected with post-Sanders’ debates over 1st century Jewish soteriology. Along the way it will reflect on the meaning of perfection language in the various corpora. The paper will then suggest that resolving this issue remains crucial for unraveling Pauline soteriology.

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Teaching Level-1 Braille Reading Skills Within A Stimulus Equivalence Paradigm To Children With Progressive Visual Impairments, Karen Ann Toussaint Jan 2009

Teaching Level-1 Braille Reading Skills Within A Stimulus Equivalence Paradigm To Children With Progressive Visual Impairments, Karen Ann Toussaint

LSU Master's Theses

Degenerative visual impairments refer to conditions that result in the progressive loss of vision; several of these conditions have their onset during childhood. Nearly 3% of the school-aged population will experience vision loss that will require specialized support, yet there has been little attempt to systematically evaluate braille-instruction programs. The current study evaluated an instructive procedure for teaching early braille-reading skills with four school-aged children with degenerative visual impairments. Following a series of pretests, braille instruction involved providing a sample braille letter and teaching the selection of the corresponding printed text letter from a comparison array. Concomitant with increases in …

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Toxicological Monitoring And Protocol Development For Abandoned Pipeline Removal In Louisiana, Forest Christopher Wootten Jan 2009

Toxicological Monitoring And Protocol Development For Abandoned Pipeline Removal In Louisiana, Forest Christopher Wootten

LSU Master's Theses

Oil/Gas extraction have left Louisiana with a legacy of abandoned infrastructure across the State. Presently, the State has developed guidelines for the removal of abandoned vessels and abandoned on shore facilities. No such guidelines exist, however, for the network of abandoned pipelines present throughout the coastal zone of Louisiana. A pipeline removal was simulated in Lake Calcasieu, LA. The site was chosen because of the presence of many abandoned pipelines and previous work done on sight to remove the on shore infrastructure. In addition, the Calcasieu is an industrial water body, with potentially hazardous pollutants sequestered in the sediments of …

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Pulsed Electric Field Influences On Acid Tolerance, Bile Tolerance, Protease Activity And Growth Characteristics Of Lactobacillus Acidophilus La-K, Olga Antonina Cueva Jan 2009

Pulsed Electric Field Influences On Acid Tolerance, Bile Tolerance, Protease Activity And Growth Characteristics Of Lactobacillus Acidophilus La-K, Olga Antonina Cueva

LSU Master's Theses

Pulsed electric field processing represents a promising non-thermal technology which involves the application of pulses of high voltage (20-80 kV/cm) for less than one second to fluid foods placed between two electrodes. During the application of certain PEF conditions microbial inactivation occurs by causing a pore formation and destruction of the cell membranes. Lactobacillus acidophilus is an important probiotic bacterium used for the production of fermented dairy products. The objective of this study was to study the influence of pulsed electric field (PEF) on the growth characteristics, bile tolerance, acid tolerance, and protease activity of Lactobacillus acidophilus LA-K. Freshly thawed …

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Passenger Car Equivalents Of Trucks Under Lane Restriction And Differential Speed Limit Policies On Four Lane Freeways, John Stanley Jan 2009

Passenger Car Equivalents Of Trucks Under Lane Restriction And Differential Speed Limit Policies On Four Lane Freeways, John Stanley

LSU Master's Theses

Lane restriction for trucks and differential speed limits for trucks and cars are becoming more common and feasible policies to improve the efficiency and safety of a freeway. It is believed that passenger car equivalents for trucks are impacted by these non typical freeway operating conditions, which are not explicitly addressed by the latest edition of the Highway Capacity Manual. Using simulated and real world data an elevated 18- mile four lane freeway was modeled under the restriction policies. The section which was used as a test bed was simulated under various control variables. Some of the control variables used …

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Ternary To Binary Converter Design In Cmos Using Multiple Input Floating Gate Mosfets, Josephine Ratna Sathiaraj Jan 2009

Ternary To Binary Converter Design In Cmos Using Multiple Input Floating Gate Mosfets, Josephine Ratna Sathiaraj

LSU Master's Theses

In this work, a ternary to binary converter circuit is designed in 0.5μm n-well CMOS technology. The circuit takes two inputs corresponding to the ternary bits and gives four outputs, which are the binary equivalent bits of the ternary inputs. The ternary inputs range from (-1,-1)3 to (1,1) 3 which are decimal -4 to 4 and the four binary output bits are the sign bit (SB), most significant bit (MSB), second significant bit (SSB) and the least significant bit (LSB). The ternary inputs (-1, 0 and 1) are represented in terms of voltages of -3V, 0V and 3V. Multiple …

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Modeling Gag Grouper (Mycteroperca Microlepis) In The Gulf Of Mexico: Exploring The Impact Of Marine Reserves On The Population Dynamics Of A Protogynous Grouper, Robert D. Ellis Jan 2009

Modeling Gag Grouper (Mycteroperca Microlepis) In The Gulf Of Mexico: Exploring The Impact Of Marine Reserves On The Population Dynamics Of A Protogynous Grouper, Robert D. Ellis

LSU Master's Theses

The gag grouper (Mycteroperca microlepis) population in the Gulf of Mexico supports both a commercial and recreational fishery but has experienced a decrease in the male to female sex ratio over the past thirty years. Protogynous fish populations naturally have a smaller male to female ratio than gonochoristic fish populations; however the decline in the gag population is such that sperm limitation may be occurring. In an effort to correct the decline in sex ratio, fishery managers have recently implemented two marine reserves designed specifically to protect gag spawning aggregations. Results from two population models (an age-structured model and an …

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Heuristics In Decision Making, Fatima M. Albar, Antonie J. Jetter Jan 2009

Heuristics In Decision Making, Fatima M. Albar, Antonie J. Jetter

Engineering and Technology Management Faculty Publications and Presentations

Heuristics are simple rules of thumbs for problem solving that follow a logic that is quite different from consequential logic. They have long been regarded, as an inferior technique for decision making that is the source of irrational decision behavior. Recently, decision making researchers have demonstrated that some heuristics are highly efficient and can compete with complex decision models in some application domains. This paper explores the different streams of research, summarizes the state of the art decision making model, and discusses its implications for complex decisions in engineering and technology management.

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Numerical Modeling Of Hemodynamics In The Thoracic Aorta And Alterations By Dacron Patch Treatment Of Aortic Coarctation, Ronak Jashwant Dholakia Jan 2009

Numerical Modeling Of Hemodynamics In The Thoracic Aorta And Alterations By Dacron Patch Treatment Of Aortic Coarctation, Ronak Jashwant Dholakia

Master's Theses (2009 -)

Coarctation of the aorta (CoA) is a major congenital heart disease, characterized by a severe stenosis of the proximal descending thoracic aorta. Traditionally, surgery has been the treatment of choice for CoA. Dacron patch aortoplasty gained increased popularity after its introduction in the mid-twentieth century due to its advantages over other surgical treatment methods available at the time. A major complication with Dacron patch aortoplasty has been the formation of late aneurysm with as much as 51% incidence reported in follow up studies. The change in aortic morphology and formation of aneurysms after Dacron patch surgery could lead to local …

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The Impacts Of Expected Structural Changes In Demand For Agricultural Commodities In China And India On World Agriculture, Alyssa Tangen Jan 2009

The Impacts Of Expected Structural Changes In Demand For Agricultural Commodities In China And India On World Agriculture, Alyssa Tangen

Agribusiness and Applied Economics

The objective of this study is to evaluate the changes in import and export demand in China and India on the United States and global agriculture in 2018. A spatial equilibrium model is developed to optimize production and trade in China, India, and other major importing and exporting regions in the world. This research focuses on four primary crops: wheat, com, rice and soybeans. In the model China and India are divided into 31 and 14 producing and consuming regions, respectively. The model also includes five exporting countries and ten importing countries/regions. The results indicate that India will be able …

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Quantitative Imaging Of Scattering Changes Associated With Epithelial Proliferation, Necrosis And Fibrosis In Tumors Using Microsampling Reflectance Spectroscopy, Venkataramanan Krishnaswamy, P Jack Hoopes, Kimberley S. Samkoe, Julia A. O'Hara, Tayyaba Hasan, Brian W. Pogue Jan 2009

Quantitative Imaging Of Scattering Changes Associated With Epithelial Proliferation, Necrosis And Fibrosis In Tumors Using Microsampling Reflectance Spectroscopy, Venkataramanan Krishnaswamy, P Jack Hoopes, Kimberley S. Samkoe, Julia A. O'Hara, Tayyaba Hasan, Brian W. Pogue

Dartmouth Scholarship

Highly localized reflectance measurements can be used to directly quantify scatter changes in tissues. We present a microsampling approach that is used to raster scan tumors to extract parameters believed to be related to the tissue ultrastructure. A confocal reflectance imager was developed to examine scatter changes across pathologically distinct regions within tumor tissues. Tissue sections from two murine tumors, AsPC-1 pancreas tumor and the Mat-LyLu Dunning prostate tumor, were imaged. After imaging, histopathology-guided region-of-interest studies of the images allowed analysis of the variations in scattering resulting from differences in tissue ultra-structure. On average, the median scatter power of tumor …

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Non-Linearity In Ecosystem Services: Temporal And Spatial Variability In Coastal Protection, Evamaria W. Koch, Edward Barbier, Brian R. Silliman, Denise J. Reed, Gerardo M. E. Perillo, Sally D. Hacker, Elise F. Granek, Jurgenne H. Primavera, Nyawira Muthiga, Stephen Polasky, Benjamin S. Halpern, Christopher J. Kennedy, Carrie V. Kappel, Eric Wolanski Jan 2009

Non-Linearity In Ecosystem Services: Temporal And Spatial Variability In Coastal Protection, Evamaria W. Koch, Edward Barbier, Brian R. Silliman, Denise J. Reed, Gerardo M. E. Perillo, Sally D. Hacker, Elise F. Granek, Jurgenne H. Primavera, Nyawira Muthiga, Stephen Polasky, Benjamin S. Halpern, Christopher J. Kennedy, Carrie V. Kappel, Eric Wolanski

Institute for Sustainable Solutions Publications and Presentations

Natural processes tend to vary over time and space, as well as between species. The ecosystem services these natural processes provide are therefore also highly variable. It is often assumed that ecosystem services are provided linearly (unvaryingly, at a steady rate), but natural processes are characterized by thresholds and limiting functions. In this paper, we describe the variability observed in wave attenuation provided by marshes, mangroves, seagrasses, and coral reefs and therefore also in coastal protection. We calculate the economic consequences of assuming coastal protection to be linear. We suggest that, in order to refine ecosystem-based management practices, it is …

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Planetary Boundaries: Exploring The Safe Operating Space For Humanity, Johan Rockström, W. L. Steffen, Kevin Noone, Åsa Persson, F. Stuart Chapin Iii, Eric Lambin, Timothy M. Lenton, Marten Scheffer, Carl Folke, Hans Joachim Schellnhuber, Björn Nykvist, Cynthia A. De Wit, Terry Hughes, Sander Van Der Leeuw, Henning Rodhe, Sverker Sörlin, Peter K. Snyder, Robert Costanza, Uno Svedin, Malin Falkenmark, Louise Karlberg, Robert W. Corell, Victoria J. Fabry, James Hansen, Brian Walker, Diana Liverman, Katherine Richardson, Paul Crutzen, Jonathan Foley Jan 2009

Planetary Boundaries: Exploring The Safe Operating Space For Humanity, Johan Rockström, W. L. Steffen, Kevin Noone, Åsa Persson, F. Stuart Chapin Iii, Eric Lambin, Timothy M. Lenton, Marten Scheffer, Carl Folke, Hans Joachim Schellnhuber, Björn Nykvist, Cynthia A. De Wit, Terry Hughes, Sander Van Der Leeuw, Henning Rodhe, Sverker Sörlin, Peter K. Snyder, Robert Costanza, Uno Svedin, Malin Falkenmark, Louise Karlberg, Robert W. Corell, Victoria J. Fabry, James Hansen, Brian Walker, Diana Liverman, Katherine Richardson, Paul Crutzen, Jonathan Foley

Institute for Sustainable Solutions Publications and Presentations

Anthropogenic pressures on the Earth System have reached a scale where abrupt global environmental change can no longer be excluded. We propose a new approach to global sustainability in which we define planetary boundaries within which we expect that humanity can operate safely. Transgressing one or more planetary boundaries may be deleterious or even catastrophic due to the risk of crossing thresholds that will trigger non-linear, abrupt environmental change within continental- to planetary-scale systems. We have identified nine planetary boundaries and, drawing upon current scientific understanding, we propose quantifications for seven of them. These seven are climate change (CO2 concentration …

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A Hypergraph Regularity Method For Linear Hypergraphs, Shoaib Amjad Khan Jan 2009

A Hypergraph Regularity Method For Linear Hypergraphs, Shoaib Amjad Khan

USF Tampa Graduate Theses and Dissertations

Szemerédi's Regularity Lemma is powerful tool in Graph Theory, yielding many applications in areas such as Extremal Graph Theory, Combinatorial Number Theory and Theoretical Computer Science. Strong hypergraph extensions of graph regularity techniques were recently given by Nagle, Rödl, Schacht and Skokan, by W.T. Gowers, and subsequently, by T. Tao. These extensions have yielded quite a few non-trivial applications to Extremal Hypergraph Theory, Combinatorial Number Theory and Theoretical Computer Science. A main drawback to the hypergraph regularity techniques above is that they are highly technical. In this thesis, we consider a less technical version of hypergraph regularity which more directly …

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Finding Confucianism In Scientology: A Comparative Analysis, John Albert Kieffer Jan 2009

Finding Confucianism In Scientology: A Comparative Analysis, John Albert Kieffer

USF Tampa Graduate Theses and Dissertations

Scientology holds considerable interest for scholars of new religious movements. As such, this study aims to contribute new data and insight to ongoing theoretical work within this area of religious studies scholarship. Engaged in this inquiry are the similarities between Scientology, the new religious movement founded in 1951 by L. Ron Hubbard (1911-1986), and the Chinese religion, Confucianism, which originates with the teachings of Confucius (551-479 BCE). Though Hubbard admits being influenced by eastern thinking such as Buddhism and Daoism in shaping his worldview, he specifically discounts Confucius as relevant in this regard. However, through comparisons between Scientology and Confucianism, …

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Numerical Heat Transfer During Partially–Confined, Confined, And Free Liquid Jet Impingement With Rotation And Chemical Mechanical Planarization Process Modeling, Jorge C. Lallave-Cortes Jan 2009

Numerical Heat Transfer During Partially–Confined, Confined, And Free Liquid Jet Impingement With Rotation And Chemical Mechanical Planarization Process Modeling, Jorge C. Lallave-Cortes

USF Tampa Graduate Theses and Dissertations

No abstract provided.

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Multiple Approaches To The Validation Of The Scores From The Study Anxiety Inventory, George Douglas Lunsford Jan 2009

Multiple Approaches To The Validation Of The Scores From The Study Anxiety Inventory, George Douglas Lunsford

USF Tampa Graduate Theses and Dissertations

The Study Anxiety Inventory (SAI), consisting of the factors of worry and emotionality, was developed to measure college students' self-reported levels of anxiety while studying for an exam. Data from 2002 undergraduate students from four colleges (Arts and Sciences, Engineering, Business, and Education) at a southeastern state university were used to evaluate the validity of the scores from the 16-item Study Anxiety Inventory. Results of confirmatory factor analyses for the two factor model, conducted separately for each college, indicated marginally acceptable fit for the data (median fit measures across the four colleges: CFI =.915, SRMR=.049, RMSEA=.098), a pattern that was …

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Mixture Distributions With Application To Microarray Data Analysis, O'Neil Lynch Jan 2009

Mixture Distributions With Application To Microarray Data Analysis, O'Neil Lynch

USF Tampa Graduate Theses and Dissertations

The main goal in analyzing microarray data is to determine the genes that are differentially expressed across two types of tissue samples or samples obtained under two experimental conditions. In this dissertation we proposed two methods to determine differentially expressed genes. For the penalized normal mixture model (PMMM) to determine genes that are differentially expressed, we penalized both the variance and the mixing proportion parameters simultaneously. The variance parameter was penalized so that the log-likelihood will be bounded, while the mixing proportion parameter was penalized so that its estimates are not on the boundary of its parametric space. The null …

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Photography’S Creative Influence On Lewis Carroll’S Alice’S Adventures In Wonderland And Through The Looking Glass And What Alice Found There, Bridget Mahoney Jan 2009

Photography’S Creative Influence On Lewis Carroll’S Alice’S Adventures In Wonderland And Through The Looking Glass And What Alice Found There, Bridget Mahoney

USF Tampa Graduate Theses and Dissertations

Lewis Carroll's novels Alice's Adventures in Wonderland and Through the Looking Glass and What Alice Found There share many characteristics with the author's photographs. Both Carroll's portraits and literature utilize dreamlike imagery to move beyond the present time and space into a dream world. The similar imagery demonstrates an important creative link between Carroll's novels and photographs. The creation of Carroll's masterpiece, Alice's Adventures in Wonderland and its sequel, Through the Looking Glass and What Alice Found There, creatively depended on the photographic images Carroll produced. Utilizing the four step process of creativity generally accepted by psychologists, Carroll's photographs are …

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Teaching Social Studies In An Age Of Globalization: A Case Study Of Secondary Social Studies Teachers’ Participation In The Una-Usa’S Global Classrooms Curriculum Program, Kelly R. Miliziano Jan 2009

Teaching Social Studies In An Age Of Globalization: A Case Study Of Secondary Social Studies Teachers’ Participation In The Una-Usa’S Global Classrooms Curriculum Program, Kelly R. Miliziano

USF Tampa Graduate Theses and Dissertations

The researcher found few studies that explore decisions of social studies teachers as they plan what and how to teach their classes. Over a century, social studies educators have adapted and responded to political, social, and economic changes. From educating immigrants a century earlier to addressing contemporary cross-border issues, social studies educators inherit unique challenges in today's increasingly globalized world. In addition to these external forces, constraints are placed on teachers which prescribe what content must be included in an already crowded curriculum. This qualitative approach using a case study provides a better understanding of the influence a globally oriented …

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Characterization Of Electrowetting Systems For Microfluidic Applications, Pradeep K. Mishra Jan 2009

Characterization Of Electrowetting Systems For Microfluidic Applications, Pradeep K. Mishra

USF Tampa Graduate Theses and Dissertations

Electrowetting is the change in apparent surface energy in the presence of an electric field. Recently, this phenomenon has been used to control the shape and location of individual droplets on a surface. However, many microfluidics researchers have acknowledged unexplained behaviors and performance degradation. In this work, electrowetting systems are characterized with different methods. The electrowetting response is measured by measuring contact angle for different applied voltages. A novel technique for direct measurement of Electrowetting Force (EWF) using nano indenter is proposed in this work. The EWF measurements show that, for aqueous solution the EWF is more as compared to …

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Gallium Nitride Sensors For Hydrogen/Nitrogen And Hydrogen/Carbon Monoxide Gas Mixtures, Christopher Nicholas Monteparo Jan 2009

Gallium Nitride Sensors For Hydrogen/Nitrogen And Hydrogen/Carbon Monoxide Gas Mixtures, Christopher Nicholas Monteparo

USF Tampa Graduate Theses and Dissertations

As hydrogen is increasingly used as an energy carrier, gas sensors that can operate at high temperatures and in harsh environments are needed for fuel cell, aerospace, and automotive applications. The high temperature Fischer-Tropsch process also uses mixtures of hydrogen and carbon monoxide to generate synthetic fuels from non-fossil precursors. As the Fischer-Tropsch process depends upon particular gas mixtures to generate various fuels, a sensor which can determine the proper ratio of reactants is needed. To this end, gallium nitride (GaN) has been used to fabricate a resistive gas sensor. GaN is a suitable semiconductor to be used in hydrogen …

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Ecis Assessment Of Cytotoxicity And Trans-Endothelial Migration Of Metastatic Cancer Cells, Daniel Opp Jan 2009

Ecis Assessment Of Cytotoxicity And Trans-Endothelial Migration Of Metastatic Cancer Cells, Daniel Opp

USF Tampa Graduate Theses and Dissertations

The investigations conducted within this dissertation centers around the use of electric cell-substrate impedance sensing (ECIS). This system is able to characterize in real-time analysis, the adhesion of cells to their substrate and neighboring cells. With this, valuable information can be gathered with in-vitro experiments regarding a tissue culture's response to physiological stimulation. This dissertation has taken advantage of ECIS' ability to analyze toxicology, barrier function, and cancer invasion on a tissue culture. With proper analysis modifications, trans-epethelial resistance (TER) can be used as a cytotoxicity assay with higher sensitivity than previously thought. In vitro assessment of cytotoxicity based on …

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Exploring Efficient Design Approaches For Display Of Multidimensional Data To Facilitate Interpretation Of Information, Chitra S. Pathiavadi Jan 2009

Exploring Efficient Design Approaches For Display Of Multidimensional Data To Facilitate Interpretation Of Information, Chitra S. Pathiavadi

USF Tampa Graduate Theses and Dissertations

Prescriptions for effective display of quantitative information involving more than two variables are not available. To explore the effectiveness of retinal variables in facilitating the interpretation of information and decision making when used in conjunction, a study with 135 participants was conducted. The study involved the use of color shape, color value, and value shape as retinal variables in interactive displays that required participants to answer nine questions in three levels of complexity (identification of data points, analyses of local comparisons and global trends). Time-on-task scores and performance scores were measured. In addition, a View Clamp eye tracker system was …

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