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Characterization Of Ultra Wideband Multiple Access Performance Using Time Hopped-Biorthogonal Pulse Position Modulation, Donald J. Clabaugh Mar 2004

Characterization Of Ultra Wideband Multiple Access Performance Using Time Hopped-Biorthogonal Pulse Position Modulation, Donald J. Clabaugh

Theses and Dissertations

The FCC's release of its UWB First Report and Order in April 2002 spawned renewed interest in impulse signaling research. This work combines Time Hopped (TH) multiple access coding with 4-ary UWB Biorthogonal Pulse Position Modulation (TH-BPPM). Multiple access performance is evaluated in a multipath environment for both synchronous and asynchronous networks. Fast time hopping is implemented by replicating and hopping each TH-BPPM symbol NH times. Bit error expressions are derived for biorthogonal TH-BPPM signaling and results compared with previous orthogonal TH-PPM work. Without fast time hopping (NH = 1), the biorthogonal TH-BPPM technique provided gains equivalent to Gray-coded QPSK; …

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Feasibility Of Using Classification Analyses To Determine Tropical Cyclone Rapid Intensification, Jonathan W. Leffler Mar 2004

Feasibility Of Using Classification Analyses To Determine Tropical Cyclone Rapid Intensification, Jonathan W. Leffler

Theses and Dissertations

Tropical cyclone intensity techniques developed by Dvorak have thus far been regarded by tropical meteorologists as the best identification and forecast schemes available using satellite imagery. However, in recent years, several ideologies have arisen which discuss alternative means of determining typhoon rapid intensification or weakening in the Pacific. These theories include examining channel outflow patterns, potential vorticity superposition and anomalies, tropical upper tropospheric trough interactions, environmental influences, and upper tropospheric flow transitions. It is now possible to data mine these atmospheric parameters thought partly responsible for typhoon rapid intensification and weakening to validate their usefulness in the forecast process. Using …

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Policy Analysis Of Chapter 101a, Readiness And Range Preservation, Of The National Defense Authorization Act For Fiscal Year 2004, William E. Sitzabee Mar 2004

Policy Analysis Of Chapter 101a, Readiness And Range Preservation, Of The National Defense Authorization Act For Fiscal Year 2004, William E. Sitzabee

Theses and Dissertations

This research analyzed the United States Air Force's ability to meet the two conditions required for exemptions of critical habitat designations that are authorized under the National Defense Authorization Act for Fiscal Year 2004. The research was limited to natural resources management on United States Air Force training ranges. Department of Defense exemptions can only be achieved if two conditions exist: the management activities must meet the intent of the Endangered Species Act and conserve the threatened and endangered species identified on the lands managed under an Integrated Natural Resources Management Plan (INRMP), and the plan must ensure that there …

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Modeling A Field Application Of In Situ Bioremediation Of Perchlorate-Contaminated Groundwater Using Horizontal Flow Treatment Wells (Hftws), Peter G. Chosa Mar 2004

Modeling A Field Application Of In Situ Bioremediation Of Perchlorate-Contaminated Groundwater Using Horizontal Flow Treatment Wells (Hftws), Peter G. Chosa

Theses and Dissertations

Perchlorate contaminated groundwater is rapidly becoming a significant environmental remediation issue for the Department of Defense. In this study, an existing numerical model that simulates the operation of a Horizontal Flow Treatment Well (HFTW) system to effect the in situ biodegradation of perchlorate through the addition of an electron donor is modified to include a submodel that describes bioclogging. Bioclogging restricts flow out of the HFTW due to the accumulation of biomass directly adjacent to the well. The modified model is then applied to an existing perchlorate contaminated site that will be used for an evaluation of the HFTW technology. …

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Decision Analysis Using Value Focused Thinking To Select Renewable Energy Sources, James S. Duke Mar 2004

Decision Analysis Using Value Focused Thinking To Select Renewable Energy Sources, James S. Duke

Theses and Dissertations

The United States is heavily dependent on fossil fuels to produce electricity. Renewable energy can provide an alternative source of energy for electricity production as well as reduce fossil fuel consumption. The executive agencies in the U.S. must also reduce greenhouse gas emissions by 2010 based on 1990 emission levels as directed by Executive Order. However, there is currently no analysis model to provide guidance toward which renewable energy to select as a course of action. This research effort used value-focused thinking decision analysis to create a model based on inputs from the Air Force Civil Engineer Support Agency. This …

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Aerobic Biodegradation Of Alternative Fuel Oxygenates In Unsaturated Soil Columns, Kevin A. Mares Mar 2004

Aerobic Biodegradation Of Alternative Fuel Oxygenates In Unsaturated Soil Columns, Kevin A. Mares

Theses and Dissertations

Groundwater contamination problems caused by methyl-tertiary butyl ether (MTBE) in subsurface waters have prompted the search for a gasoline oxygenate replacement. In order to avoid the problems encountered with MTBE, it is prudent to evaluate the fate and transport in the subsurface of proposed replacements, such as ethanol. In this study, ethanol transport and degradation in unsaturated soil was investigated using a series of eight soil columns. This preliminary study was to see if the soil column system components functioned properly, how similarly the eight soil columns performed, and if soil oxygen concentration affected degradation of ethanol. Tracer tests, using …

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An Evaluation Of Vegetated Roofing Technology: Application At Air Force Plant Four, Building 15, Benjamin J. Morgan Mar 2004

An Evaluation Of Vegetated Roofing Technology: Application At Air Force Plant Four, Building 15, Benjamin J. Morgan

Theses and Dissertations

The United States Air Force maintains thousands of facilities around the world. Many of these facilities have asphalt built up roofs or some other less than sustainable roofing system. In an effort to find roofing systems suitable for Air Force facilities that are both economically and environmentally friendly, this thesis investigated vegetated roofing as a possible alternative to conventional roofing systems. While vegetated roofs are a relatively new roofing system, they exhibit performance qualities that seem to be in line with Air Force needs. An investigation into the feasibility of vegetated roofing technology revealed that this roofing system has many …

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Application Of Horizontal Flow Treatment Wells For In Situ Treatment Of Mtbe-Contaminated Groundwater, Preston F. Rufe Mar 2004

Application Of Horizontal Flow Treatment Wells For In Situ Treatment Of Mtbe-Contaminated Groundwater, Preston F. Rufe

Theses and Dissertations

This study utilized a three-dimensional numerical model to evaluate the potential application of HFTWs to manage MTBE-contaminated groundwater. HFTWs consist of two dual-screened treatment wells. One well operates in an upflow mode, with MTBE-contaminated water extracted from an aquifer through a screen in the deep portion of an aquifer and injected into the aquifer through a shallow well screen, while the adjacent well operates in a downflow mode, extracting water from the shallow zone of the aquifer and injecting it into the deep zone. As the MTBE-contaminated water flows through the wells, an electron acceptor and/or another electron donor is …

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An Evaluation Of Formic Acid As An Electron Donor For Palladium (Pd) Catalyzed Destruction Of Nitroaromatic Compounds, Mark R. Stevens Mar 2004

An Evaluation Of Formic Acid As An Electron Donor For Palladium (Pd) Catalyzed Destruction Of Nitroaromatic Compounds, Mark R. Stevens

Theses and Dissertations

The Department of Defense is responsible for over 2,000 hazardous waste sites containing nitroaromatic compounds (NACs) such as 2,4,6-TNT, 2,4- and 2,6-DNT that resulted from the production and use of munitions throughout the nation and world, NACs are typically persistent in natural environments, though they can be oxidized or reduced under engineered conditions, NACs and their reduction products are toxic chemicals and suspected human carcinogens, Both TNT and 2,4-DNT are listed as priority pollutants by the U,S EPA, This study investigates the effectiveness of using a palladium (Pd) catalyst in concert with formic acid as an electron donor to reduce …

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Effect Of Equivalence Ratio And G-Loading On In-Situ Measurements Of Chemiluminescence In An Ultra Compact Combustor, Jason M. Armstrong Mar 2004

Effect Of Equivalence Ratio And G-Loading On In-Situ Measurements Of Chemiluminescence In An Ultra Compact Combustor, Jason M. Armstrong

Theses and Dissertations

Using a spectrometer and high temperature fiber optics the relative intensities of the near-infrared, visible, and ultraviolet radiation emitted from the C2*, CH*, and OH* radicals were measured at eight discrete locations within the Ultra Compact Combustor test rig. Blackbody radiation in the near infrared also was observed. The tests were conducted at various g-loadings and overall equivalence ratios and with various air hole configurations. These measurements were compared to determine the effect of these changes on the radiation emitted. Local C2* intensities were used to estimate the flame location within the combustor and the local CH*/OH* ratio was used …

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Swarming Reconnaissance Using Unmanned Aerial Vehicles In A Parallel Discrete Event Simulation, Joshua J. Corner Mar 2004

Swarming Reconnaissance Using Unmanned Aerial Vehicles In A Parallel Discrete Event Simulation, Joshua J. Corner

Theses and Dissertations

Current military affairs indicate that future military warfare requires safer, more accurate, and more fault-tolerant weapons systems. Unmanned Aerial Vehicles (UAV) are one answer to this military requirement. Technology in the UAV arena is moving toward smaller and more capable systems and is becoming available at a fraction of the cost. Exploiting the advances in these miniaturized flying vehicles is the aim of this research. How are the UAVs employed for the future military? The concept of operations for a micro-UAV system is adopted from nature from the appearance of flocking birds, movement of a school of fish, and swarming …

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Visual Debugging Of Object-Oriented Systems With The Unified Modeling Language, Wendell E. Fox Mar 2004

Visual Debugging Of Object-Oriented Systems With The Unified Modeling Language, Wendell E. Fox

Theses and Dissertations

The Department of Defense (DoD) is developing a Joint Battlespace Infosphere, linking a large number of data sources and user applications. Debugging and analysis tools are required to aid in this process. Debugging of large object-oriented systems is a difficult cognitive process that requires understanding of both the overall and detailed behavior of the application. In addition, many such applications linked through a distributed system add to this complexity. Standard debuggers do not utilize visualization techniques, focusing mainly on information extracted directly from the source code. To overcome this deficiency, this research designs and implements a methodology that enables developers …

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Supply Chain Management In Humanitarian Relief Logistics, William K. Rodman Mar 2004

Supply Chain Management In Humanitarian Relief Logistics, William K. Rodman

Theses and Dissertations

Hundreds of millions of people are affected by disasters each year. This thesis explores the use of supply chain management techniques to overcome the barriers encountered by logistics managers during humanitarian relief operations. Using grounded theory methodology, barriers were analyzed based on academic, organizational, and contemporary literature. Possible solutions to these barriers were selected from available supply chain management literature. This work is different from others in that it marries supply chain principles from different disciplines (including private, nonprofit, and military sectors) to benefit humanitarian operations. It also serves to advance the body of knowledge on this subject so that …

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Isolated Ventricular Myocyte Contractile Function Is Depressed In Rats Fed High Fat And/Or Marginally Copper -Deficient Diets., David P. Relling Feb 2004

Isolated Ventricular Myocyte Contractile Function Is Depressed In Rats Fed High Fat And/Or Marginally Copper -Deficient Diets., David P. Relling

Theses and Dissertations

Obesity is influenced by dietary consumption of fat while much of the population consumes a diet deficient of the trace mineral copper. Obesity and copper deficiency can alter cardiovascular function; including cardiac hypertrophy, increased myocyte lipid droplet volume, and cardiac contractile depression. Interestingly, lipotoxic dysfunction is characterized by many of the same mechanistic alterations that are observed in obesity and copper deficiency. Additionally, the sphingolipid ceramide is elevated in lipotoxic dysfunction. However, functional leptin:leptin receptor signaling prevents lipotoxic dysfunction. The purpose of my dissertation was to determine the role of a high fat and marginal copper deficient diet on cardiac …

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Developmental Regulation Of Apoptosis In Zebrafish Oocytes, 64-Cell Stage Blastomeres, And Germ-Ring Stage Embryos, Javier Francisco Negrón Jan 2004

Developmental Regulation Of Apoptosis In Zebrafish Oocytes, 64-Cell Stage Blastomeres, And Germ-Ring Stage Embryos, Javier Francisco Negrón

Theses and Dissertations

The zebrafish early embryo acquires a general capability for apoptosis as a consequence of passage through the maternal-zygotic transition, the time that marks the beginning of zygotic transcription and the degradation of inherited maternal factors. We describe in detail the origin and regulation of the programmed cell death machinery found in the zebrafish early embryo. To elicit an apoptotic response from zebrafish early embryos, gastrulating germ-ring stage embryos were chronically exposed to the protein synthesis inhibitor cycloheximide. Chronic exposure of germ-ring stage embryos to cycloheximide resulted in the rapid activation of an apoptotic response by the embryos, which was evident …

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Determination Of Four Production Indicators In Llama (Lama Glama) Herds In Ayllu Pumasara, Saucari, Oruro, Magin Herrera Lopez Jan 2004

Determination Of Four Production Indicators In Llama (Lama Glama) Herds In Ayllu Pumasara, Saucari, Oruro, Magin Herrera Lopez

Theses and Dissertations

Camelid exploitation, despite its economic antiquity in our nation, recently has awakened greater interest in investigators. Currently, there are more than 2,500,000 llamas in the Altiplano, which is the highest number of camelids on the world. Production is organic, with the llama capital of Bolivia being the department of Oruro. This work's objective is to determine four production parameters: composition and structure of llama herds, percentage of births, cria [calf] mortality, and crias that reach 5 months old, in 3 communities of Ayllu Pumasa of Saucar’ province, department of Oruro. The llama-raising system is traditional and herds contain more than …

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Effect Of Canihua (Chenopodium Pallidicaule Aellen), Wheat (Triticum Aestivum L.), And Soybean (Glycine Max M) Sprouts On The Feeding Of Guinea Pigs For Growth, Eddy Wilfredo Calle Ayma Jan 2004

Effect Of Canihua (Chenopodium Pallidicaule Aellen), Wheat (Triticum Aestivum L.), And Soybean (Glycine Max M) Sprouts On The Feeding Of Guinea Pigs For Growth, Eddy Wilfredo Calle Ayma

Theses and Dissertations

This study occurred during July, August, and September in the Small Animals Investigation and Production Center (CIPAM), dependent of the Faculty of Agricultural, Livestock, and Veterinary Sciences of the Technical University of Oruro, of the Central Highland of Bolivia. In order to satisfy guinea pig nutrition requirements, which are 2800.00 kcal/kg of energy, 18.00% protein, 10.00% fiber, 1.00% calcium, and 0.60% phosphorus, the following ingredients were used in feed: 11.30% yellow corn, 30.00% milled wheat [Bromus catharticus], 14.00% soy cake, 32.00% wheat bran, 9.00% alfalfa flour, 1.80% bone flour, 1.00% conchilla, 0.50% common salt, and 0.40% methionine. The effect that …

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Determination Of The Nutritional Level Of Calcium And Phosphorus In Llamas (Lama Glama) In Two Seasons In The Condoriri Agricultural Experiment Center, Gustavo Adolfo León Titichoca Jan 2004

Determination Of The Nutritional Level Of Calcium And Phosphorus In Llamas (Lama Glama) In Two Seasons In The Condoriri Agricultural Experiment Center, Gustavo Adolfo León Titichoca

Theses and Dissertations

The concentrations of calcium and phosphorus were determined in 12 llamas from the Condoriri Agricultural Experiment Center (Oruro Technical University) of Oruro, Bolivia during two seasons (wet and dry) and at three ages (newborn, juvenile, and adult). Samples of flesh were taken from the arm, leg, back, rib, and neck. Pasture samples (grassland and prairie) were used to determine the rate of biting of each animal studied. The blood samples were taken by extracting blood from a jugular vein. The minerals (Ca and P) in the flesh are highest in the wet season, 113.78 mg/100 g. The newborns were found …

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Botanical And Chemical Composition Of Diets Selected By Alpacas (Lama Pacos) Pastured In The Ulla Ulla Wetlands, Lino Constancio López López Jan 2004

Botanical And Chemical Composition Of Diets Selected By Alpacas (Lama Pacos) Pastured In The Ulla Ulla Wetlands, Lino Constancio López López

Theses and Dissertations

This study was done in the subtropical high Andes of Ulla Ulla. Its objectives were to determine the botanical composition, nutritional value, and preferred forages in the wetlands (hydromorphic and mesico) diet, by season (dry and wet), and by botanical family (12 families). Three-hundred sixty samples were collected from 6 alpacas with esophageal fistulations, and from them nutritional value and botanical composition were determined; the latter was compared with the botanical composition of the wetlands to determine preference. The results are highly significant (p<0.01) for botanical families, interaction between season and family, interaction of wetland type and family, and interaction of the season with wetland type and family. Species from the family Juncaceae were the most consumed with 27.78%, followed by moderate consumption of Cyperaceae (21.03%), Gramineae (15.02%), and Rosaceae (12.39%). Lower consumption occurred with Umbeliferaceae and Asteraceae with 6.61% and 5.64%, respectively, and the lowest consumption was of Plantaginaceae, Scrophulariaceae, minor plants, Gentianiaceae, unidentified plants, and Ranunculaceae with 2.86%, 2.50%, 2.17%, 2.08%, 1.03%, and 0.89%, respectively. The botanical families with the greatest preference value (PV) were Gramineae (PV=6.48), Scrophulariaceae (PV=8.75), Gentianiaceae (PV=7.55), and Ranunculaceae (PV=8.16). Proportional preference was observed in Juncaceae (PV=1.49), Cyperaceae (PV= -1.72), Rosaceae (PV=1.82), and Umbeliferaceae (PV= -0.82). The Asteraceae family was classified as a forced preference (PV= -6.29). The average nutritional value of the diet shows high values: 14.69% of raw protein, 14.58% ash, 85.42% organic matter, 21.43% raw fiber, and 31.00% neutral detergent fiber. It was concluded that alpacas efficiently select their diet for nutritional value, however, consumption is not appropriate, which results in negative live weight gain, especially in the dry season. On the other hand, the plants' preference values correspond to the lowest and one of the highest is a forced preference, according to the botanical composition of the wetland, which suggests that the preferred plants are repeatedly consumed in current continual pastures, and that alpacas are forced to consume unpalatable plants. This reflects on bad CANAPAS wetlands management in Ulla Ulla. Consequently, reversing this situation implies changes in pasture management and a reduction of the animal load.

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Emission Analysis Of Biodiesel In A Commercial Aircraft Engine, Venus Rivera Larson Jan 2004

Emission Analysis Of Biodiesel In A Commercial Aircraft Engine, Venus Rivera Larson

Theses and Dissertations

No abstract provided.

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Monthly And Seasonal Estimates Of Carbon Dioxide Emissions From Fossil Fuel Consumption In Canada, Mexico, Brazil, The United Kingdom, France, Spain, Italy And Poland, London M. Losey Jan 2004

Monthly And Seasonal Estimates Of Carbon Dioxide Emissions From Fossil Fuel Consumption In Canada, Mexico, Brazil, The United Kingdom, France, Spain, Italy And Poland, London M. Losey

Theses and Dissertations

No abstract provided.

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Effect Of Bulbourethrectomy And Collection Frequency On Macro- And Microscopic Characteristics Of Llama (Lama Glama) Ejaculate, Víctor Efrain Gonzáles Vargas Jan 2004

Effect Of Bulbourethrectomy And Collection Frequency On Macro- And Microscopic Characteristics Of Llama (Lama Glama) Ejaculate, Víctor Efrain Gonzáles Vargas

Theses and Dissertations

This study occurred in the Rural Academic Unit-Tiahuanaco installations, of the Bolivian Catholic University-La Paz, Bolviia, with the objective of evaluating macro- and microscopic characteristics of sperm ejaculation from bulbourethrectomized llamas. Six q'ara-variety male llamas of 3, 4, and 5 years of age were used over 8 weeks during which they were fed with natural and cultivated pastures. Ejaculate was collected with an artificial vagina with stimulation (libido) of male llamas by female llamas, for macro- and microscopic evaluation (volume, pH, color, appearance, motility, concentration, and sperm vitality). The results obtained were: average volume of 0.55[+or-]0.36 ml, with a CV …

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Student Perceptions Of Concomitant Learnings Of East Lab In A Small, Rural Arkansas School District, Judith Lane Bynum Jan 2004

Student Perceptions Of Concomitant Learnings Of East Lab In A Small, Rural Arkansas School District, Judith Lane Bynum

Theses and Dissertations

The purpose of this research was to study the evidence of concomitant learnings that are a result of a technology-rich, project-based learning environment; the empowerment of the student by these learnings; and their worth in better preparing high school students for college success. This qualitative, phenomenological study used interviews of present and past EAST Lab students from a small, rural Arkansas school district as its data. The interview questions focused on comparison and contrast of the learning environments of the students' classes, affective and cognitive knowledge gained from these environments; and student opinions concerning the influence of the EAST experience …

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The Effects Of A One-Tesla Magnet On Human Fibroblast Cell Growth, Ashley Chaplin Jan 2004

The Effects Of A One-Tesla Magnet On Human Fibroblast Cell Growth, Ashley Chaplin

Theses and Dissertations

The controversy regarding the ill effects of electromagnetic fields began in 1979 when Nancy Wertheimer and Ed Leeper claimed to have found a connection between childhood leukemia and power lines. In 1997, a group of researchers led by Martha Linet, M. D., attempted to provide evidence that there was no link between cancer and electromagnetic fields. The study showed that the risk of acute lymphoblastic leukemia did not escalate with increasing electromagnetic field levels in the children's homes. When compared to the Earth's static magnetic field of 0.5 Gauss, these fields were extremely small. Within the past decade, magnets have …

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Analysis And Prediction Of West Nile Virus Distribution In North America Using General Unary Hypothesis Automation, Bharath Panyadahundi Jan 2004

Analysis And Prediction Of West Nile Virus Distribution In North America Using General Unary Hypothesis Automation, Bharath Panyadahundi

Theses and Dissertations

No abstract provided.

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Hate Crime Depicted In Film, Waylon C. Baker Jan 2004

Hate Crime Depicted In Film, Waylon C. Baker

Theses and Dissertations

No abstract provided.

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Remote Sensing And Predictive Modeling Of Saltcedar (Tamarix) In The Northern Great Plains, David A. Brookman Jan 2004

Remote Sensing And Predictive Modeling Of Saltcedar (Tamarix) In The Northern Great Plains, David A. Brookman

Theses and Dissertations

No abstract provided.

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Representing And Negotiating Dakotaness In Susan Power, Aneliya Dimitrova Jan 2004

Representing And Negotiating Dakotaness In Susan Power, Aneliya Dimitrova

Theses and Dissertations

No abstract provided.

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Reflections, Laura Love Higbee Jan 2004

Reflections, Laura Love Higbee

Theses and Dissertations

Much of my artistic inspiration comes from my walks in nature. I explore the many different textures of stones, wood chips, tree bark, water ripples, lily pads, birds' feathers, and webbed feet. I find that the reflections on the surface of a pond, and the shadows and highlights on my subjects, are most beautifully captured as they are veiled by the dusk sunset. Sometimes I prefer to capture an image more inclusive of the environment. Other times I am more intrigued by the up close view of a subject, sometimes abstracting it. Through photography I can capture the quiet moments …

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Fauxtopia, Raymond William Kampf Jan 2004

Fauxtopia, Raymond William Kampf

Theses and Dissertations

To all who come to this fictitious place:Welcome.Fauxtopia is your land. Here, age relives distorted memories of the past, and here, youth may savor the challenge of trying to understand the present. Fauxtopia is made up of the ideals, the dreams and the fuzzy facts which have re-created reality... with the hope that it will be a source of edutainment for all the world.Ray KampfFauxtopia DedicationApril 1st, 2004

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