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Blending The Battlefield: An Analysis Of Using Private Military Companies To Support Military Operations In Iraq, Heather L. Gallup Mar 2008

Blending The Battlefield: An Analysis Of Using Private Military Companies To Support Military Operations In Iraq, Heather L. Gallup

Theses and Dissertations

Over the past fifteen years, the Department of Defense has experienced an increasing trend in the outsourcing and privatization of military operations. Key factors contributing to the growth include declines in military budgets, reductions in active duty end-strength, increases in operational deployments, advancements in weapon system technology, and evolutions in the nature of warfare. However, the continued escalation of incorporating Private Military Companies (PMCs) on the battlefield creates unique challenges. The purpose of this exploratory and descriptive research is to identify utilization rates, describe the types of roles being fulfilled, and synthesize the challenges of augmenting military manpower with civilian …

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Nucleoplasmic And Cytoplasmic Degradation Of Telomerase: Implications Toward Telomerase-Based Cancer Therapy, Binh Nguyen Mar 2008

Nucleoplasmic And Cytoplasmic Degradation Of Telomerase: Implications Toward Telomerase-Based Cancer Therapy, Binh Nguyen

Theses and Dissertations

Telomerase is a ribonucleoprotein that is reactivated in cancer cells to allow for continuous cellular division and indefinite growth. With telomerase being expressed in more than 85% of all cancer, it is imperative that we understand how to selectively inactivate and degrade this unique DNA polymerase. In doing so, we can specifically target tumor cells to erode their telomeres so that they will undergo apoptosis or senescence. Through this research, we have learned that telomerase can be degraded in the nucleoplasm by Hsp90 chaperone inhibition and in the cytoplasm by the dominant negative mutant, D712A V713I. These findings should guide …

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The Neglect Of Divorce In Marital Research: An Ontological Analysis Of The Work Of John Gottman, Joseph Andrew Ostenson Mar 2008

The Neglect Of Divorce In Marital Research: An Ontological Analysis Of The Work Of John Gottman, Joseph Andrew Ostenson

Theses and Dissertations

This thesis explores why the divorce rate has remained relatively stable over the past few decades, even in the face of rapidly growing social sciences – particularly the branch associated with the study and treatment of marriage – through an analysis of the work of John Gottman. This thesis chiefly claims that divorce is not addressed in marital research. It is argued, however, that far from being intentional on the part of researchers, the disregard for divorce in the marital research is actually due to underlying, unrecognized assumptions. Specifically, this thesis analyzes the most fundamental assumptions – the ontological assumptions …

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The Scholarship Of Teaching: Contributing Factors To Improved Teaching Performance Among University Faculty Members, Whitney Ransom Mar 2008

The Scholarship Of Teaching: Contributing Factors To Improved Teaching Performance Among University Faculty Members, Whitney Ransom

Theses and Dissertations

This thesis brings a much-needed focus on the quality and scholarship of teaching as it pertains to educational and faculty development. The main purpose of this paper is to outline what more than 200 faculty members across a wide variety of disciplines have focused on over a three-year period to make significant (a 1.5 standard deviation increase or higher in online student ratings) and sustained improvements in their teaching. The top three factors of improvement include active/practical learning, teacher/student interactions, and clear expectations/learning outcomes. The researcher also discusses how institutions and faculty communities of practice, research, and faculty personality contribute …

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The Maya Footprint: Soil Resources Of Chunchucmil, Yucatan, Mexico, Ryan V. Sweetwood Mar 2008

The Maya Footprint: Soil Resources Of Chunchucmil, Yucatan, Mexico, Ryan V. Sweetwood

Theses and Dissertations

Agricultural yields in Northwest Yucatán are constrained by climate, thin soils, and low fertility. Despite this, the ancient Maya city of Chunchucmil Yucatán, Mexico, boasted an immense, dense, and wealthy population during the Middle Classic period (ca A.D. 400-700). Soil physical and chemical properties were explored to determine how the ancient Maya of Chunchucmil fed themselves. Soil profiles were collected from various locations within ancient Chunchucmil's suspected sustaining area. The physical and chemical properties, carbon isotopes, black carbon, and coprostanols of soil profiles sampled were compared to ancient rural settlement and remotely sensed images, such as AIRSAR (airborne synthetic aperture …

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Characterization Of A Fluorescent Protein Reporter System, Sandra J. Dias Mar 2008

Characterization Of A Fluorescent Protein Reporter System, Sandra J. Dias

Theses and Dissertations

Chemical and biological threats are ever present and attacks have occurred throughout the world in both war and peace-time. Multiple government agencies, academia, and private industry are developing detection capabilities to address such threats. The research presented in this paper supports development of a modular synthetic biology based system that detects and reports the presence of a threat agent. Synthetic biology builds upon past research in genetic engineering and seeks to combine broad applications within biotechnology in novel ways. This basic research project will help to demonstrate a proof-of-concept design which will guide future studies on the development of a …

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Spirituality And Religious Support As Buffers Against The Negative Effects Of Marital Distress On Ambulatory Blood Pressure, John Dale Livingstone Mar 2008

Spirituality And Religious Support As Buffers Against The Negative Effects Of Marital Distress On Ambulatory Blood Pressure, John Dale Livingstone

Theses and Dissertations

The beneficial effects of religion and spiritual factors on cardiovascular functioning have become an area of increasing research. Similarly, considerable research has also investigated the negative effects of marital distress on cardiovascular functioning. Little is known, however, about potential protective factors against the deleterious effects of marital distress on cardiovascular functioning. Social support has been identified as a potential buffer against the negative effects of marital distress on ambulatory blood pressure, and the current study hypothesized that spirituality, religiosity, and religious support would also buffer the negative effects of marital distress on ambulatory blood pressure. Fifty-eight married couples were recruited …

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Improving Liquid State Machines Through Iterative Refinement Of The Reservoir, R David Norton Mar 2008

Improving Liquid State Machines Through Iterative Refinement Of The Reservoir, R David Norton

Theses and Dissertations

Liquid State Machines (LSMs) exploit the power of recurrent spiking neural networks (SNNs) without training the SNN. Instead, a reservoir, or liquid, is randomly created which acts as a filter for a readout function. We develop three methods for iteratively refining a randomly generated liquid to create a more effective one. First, we apply Hebbian learning to LSMs by building the liquid with spike-time dependant plasticity (STDP) synapses. Second, we create an eligibility based reinforcement learning algorithm for synaptic development. Third, we apply principles of Hebbian learning and reinforcement learning to create a new algorithm called separation driven synaptic modification …

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The Effects Of A Resveratrol Derivative On Regulatory Behaviors And Reproductive Health In Male And Female Long-Evans Rats, Kimberly Michelle Fabick Mar 2008

The Effects Of A Resveratrol Derivative On Regulatory Behaviors And Reproductive Health In Male And Female Long-Evans Rats, Kimberly Michelle Fabick

Theses and Dissertations

Phytoestrogens are chemicals produced by plants that act like estrogens and have the ability to bind to the mammalian estrogen receptor system. The purpose of this study is to evaluate a new phytoestrogen analog called 4-acetoxy Resveratrol. Resveratrol is a phytoestrogen that has been found in the skin of grapes. Resveratrol has been shown to be able to bind to the estrogen receptors and has a similar molecular structure as estradiol. Resveratrol has been shown to have many positive health benefits such as improving cardiovascular health, serving as a neuroprotective agent, acting as an anti-inflammatory agent, working as an anti-cancer …

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Mechanisms By Which Apoptotic Membranes Become Susceptible To Secretory Phospholipase A2, Rachel Williams Bailey Mar 2008

Mechanisms By Which Apoptotic Membranes Become Susceptible To Secretory Phospholipase A2, Rachel Williams Bailey

Theses and Dissertations

During apoptosis, changes occur in T-lymphocyte membranes that render them susceptible to hydrolysis by secretory phospholipase A2 (sPLA2). To study the relevant mechanisms, a simplified model of apoptosis using a calcium ionophore was first applied. Kinetic and flow cytometry experiments provided key observations regarding ionophore treatment: initial hydrolysis rate was elevated, total reaction product was increased four-fold, and adsorption of the enzyme to the membrane surface was unaltered. Analysis of these results suggested that susceptibility during calcium-induced apoptosis is limited by substrate availability rather than enzyme adsorption. Fluorescence experiments identified three membrane alterations that might affect substrate access to the …

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The Effects Of Prenatally Administered Phytoestrogens On The Reproductive And Behavioral Development Of Long-Evans Rats, Crystal Blake Mar 2008

The Effects Of Prenatally Administered Phytoestrogens On The Reproductive And Behavioral Development Of Long-Evans Rats, Crystal Blake

Theses and Dissertations

Equol is known to be a selective androgen modulator and has the ability to bind and inhibit 5-alpha dihydrotestosterone (5α-DHT). Equol is also a selective estrogen receptor modulator and is able to bind beta estrogen receptors with high affinity. As estrogen receptors are found in the hypothalamus, pituitary, and gonads, prenatally administered equol could affect the morphological and reproductive development of offspring. To test this hypothesis, during gestational days 14 to 20, forty-two pregnant Long-Evans rats were given one of six treatments: 1) no treatment, 2) injection with dimethyl sulfoxide (DMSO), 3) injection with 10 mg/kg equol, 4) injection with …

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Biomimetic Micro Air Vehicle Testing Development And Small Scale Flapping-Wing Analysis, Craig E. Svanberg Mar 2008

Biomimetic Micro Air Vehicle Testing Development And Small Scale Flapping-Wing Analysis, Craig E. Svanberg

Theses and Dissertations

The purpose of this research was to develop testing methods capable of analyzing the performance of a miniature flapping-wing mechanism that can later be adapted to a biomimetic micro air vehicle (MAV). Three small scale flapping mechanisms capable of single plane flapping, flapping with active pitch control, and flapping/pitch with out-of-plane movement were designed using SolidWorks. The flapping-only model was fabricated on an Objet Eden 500V 3-dimensional printer. The flapping mechanism was mounted on an aluminum plate supported by air bearings, and thrust was measured for a variety of conditions. The testing was conducted using wings composed of carbon fiber …

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Analyzing Carbohydrate-Based Regenerative Fuel Cells As A Power Source For Unmanned Aerial Vehicles, Olek Wojnar Mar 2008

Analyzing Carbohydrate-Based Regenerative Fuel Cells As A Power Source For Unmanned Aerial Vehicles, Olek Wojnar

Theses and Dissertations

Based on current capabilities, we examine the feasibility of creating a carbohydrate-based regenerative fuel cell (CRFC) as the primary power source for unmanned aerial vehicles (UAV) for long endurance missions where station keeping is required. A CRFC power system is based on a closed-loop construct where carbohydrates are generated from zooxanthellae, algae that create excess carbohydrates during photosynthesis. The carbohydrates are then fed to a carbohydrate fuel cell where electric power is generated for the UAV’s propulsion, flight control, payload, and accessory systems. The waste products from the fuel cell are used by the zooxanthellae to create more carbohydrates, therefore …

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Transcendental Exchange: Alchemical Discourse In Romantic Philosophy And Literature, Elizabeth Olsen Brocious Mar 2008

Transcendental Exchange: Alchemical Discourse In Romantic Philosophy And Literature, Elizabeth Olsen Brocious

Theses and Dissertations

Alchemical imagery and ideology is present in many Romantic works of literature, but it has largely been overlooked by literary historians in their contextualization of the time period. The same can be said for mysticism in general, of which alchemy is a subset. This project accounts for alchemy in the works of transcendental philosophers and writers as it contributes to some of the most important conversations of the Romantic time period, particularly the reaction against empirical philosophy and the articulation of creative processes. The transcendental conversation is a transnational one, encompassing Germany, Britain, and America, with its use of alchemy …

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In Vitro Toxicity Of Aluminum Nanoparticles In Human Keratinocytes, Stephanie Mccormack-Brown Mar 2008

In Vitro Toxicity Of Aluminum Nanoparticles In Human Keratinocytes, Stephanie Mccormack-Brown

Theses and Dissertations

Nanotechnology promises to be the defining technology of the 21st century. At an annual investment of $1B, it provides significant contributions to manufacturing, medicine, energy conservation, and the environment. Nanoparticles are structures with at least one dimension in the 1 to 100 nanometer (nm) range. DoD and US Air Force interest in aluminum nanoparticles (AL NPs) stems from its ability to enhance combustion jet fuel, thus increasing fuel efficiency. The addition of AL NPs to JP-8 may pose a unique dermal hazard to aircraft maintenance workers. There is no published data on AL NP toxicity effects on human skin. This …

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An Ontology Centric Architecture For Mediating Interactions In Semantic Web-Based E-Commerce Environments, Manoj Thomas Mar 2008

An Ontology Centric Architecture For Mediating Interactions In Semantic Web-Based E-Commerce Environments, Manoj Thomas

Theses and Dissertations

Information freely generated, widely distributed and openly interpreted is a rich source of creative energy in the digital age that we live in. As we move further into this irrevocable relationship with self-growing and actively proliferating information spaces, we are also finding ourselves overwhelmed, disheartened and powerless in the presence of so much information. We are at a point where, without domain familiarity or expert guidance, sifting through the copious volumes of information to find relevance quickly turns into a mundane task often requiring enormous patience. The realization of accomplishment soon turns into a matter of extensive cognitive load, serendipity …

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In Vitro Toxicity And Inflammation Response Induced By Copper Nanoparticles In Rat Alveolar Macrophages, Brian M. Clarke Mar 2008

In Vitro Toxicity And Inflammation Response Induced By Copper Nanoparticles In Rat Alveolar Macrophages, Brian M. Clarke

Theses and Dissertations

Nanotechnology is a thriving industry and has the potential to benefit society in numerous ways. However, not all environmental and human health concerns of nanomaterials have been addressed. Thus, the purpose of this research was to investigate the toxicity and inflammation potential (using cytokines TNF-alpha and IL-6 as indicators) of various sized copper nanoparticles (40, 60, and 80 nm) in rat alveolar macrophages. Toxicity measurements were accomplished by means of in vitro techniques and toxicity mechanisms were studied by measuring reactive oxygen species (ROS) production. In addition, cytokine measurements used enzyme-linked immunosorbent assay (ELISA) methods. Results show copper nanoparticles as …

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Analysis Of The Psychometric Properties Of Two Different Concept-Map Assessment Tasks, Kenneth James Plummer Mar 2008

Analysis Of The Psychometric Properties Of Two Different Concept-Map Assessment Tasks, Kenneth James Plummer

Theses and Dissertations

The ability to make sense of a wide array of stimuli presupposes the human tendency to organize information in a meaningful way. Efforts to assess the degree to which students organize information meaningfully have been hampered by several factors including the idiosyncratic way in which individuals represent their knowledge either with words or visually. Concept maps have been used as tools by researchers and educators alike to assist students in understanding the conceptual interrelationships within a subject domain. One concept-map assessment in particular known as the construct-a-map task has shown great promise in facilitating reliable and valid inferences from student …

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Dialable Cryptography For Wireless Networks, Marnita T. Eaddie Mar 2008

Dialable Cryptography For Wireless Networks, Marnita T. Eaddie

Theses and Dissertations

The objective of this research is to develop an adaptive cryptographic protocol, which allows users to select an optimal cryptographic strength and algorithm based upon the hardware and bandwidth available and allows users to reason about the level of security versus the system throughput. In this constantly technically-improving society, the ability to communicate via wireless technology provides an avenue for delivering information at anytime nearly anywhere. Sensitive or classified information can be transferred wirelessly across unsecured channels by using cryptographic algorithms. The research presented will focus on dynamically selecting optimal cryptographic algorithms and cryptographic strengths based upon the hardware and …

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Constellation Design Of Geosynchronous Navigation Satellites Which Maximizes Availability And Accuracy Over A Specified Region Of The Earth, Halil Ibrahim Ozdemir Mar 2008

Constellation Design Of Geosynchronous Navigation Satellites Which Maximizes Availability And Accuracy Over A Specified Region Of The Earth, Halil Ibrahim Ozdemir

Theses and Dissertations

Currently, there are four Global Navigation Satellite Systems (GNSS) either being developed or in existence-GPS, GLONASS, Compass, and Galileo. Additionally, there are several Regional Navigation Satellite Systems (RNSS) planned or in existence, as well as numerous augmentation systems (which require a GNSS for operation). It can be anticipated that there will be interest in developing additional independent regional navigation satellite systems to cover areas of interest to particular countries or regions, who want to have their own system. In this paper, a genetic algorithm is used in an effort to determine near-optimal RNSS constellations. First, a cost function is setup, …

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Microfluidic Power Generation, Aaron J. Sprecher Mar 2008

Microfluidic Power Generation, Aaron J. Sprecher

Theses and Dissertations

This thesis includes the detailed mathematical calculations used to determine the feasibility of harnessing electrical energy from the blood flow through human capillaries. The designs are inspired by human physiology and well established electromagnetic energy harvesting techniques and the fabrication methods have been proposed for the various components of the device. The fabrication and the design of these components have also been extensively analyzed using calculations based on the governing principles of microfluidics, kinetics, and electromagnetics. The analysis has confirmed that this design can produce sufficient energy to power a MEMS device using non-standard materials and fabrication methods. The designs …

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Anti-Tamper Method For Field Programmable Gate Arrays Through Dynamic Reconfiguration And Decoy Circuits, Samuel J. Stone Mar 2008

Anti-Tamper Method For Field Programmable Gate Arrays Through Dynamic Reconfiguration And Decoy Circuits, Samuel J. Stone

Theses and Dissertations

As Field Programmable Gate Arrays (FPGAs) become more widely used, security concerns have been raised regarding FPGA use for cryptographic, sensitive, or proprietary data. Storing or implementing proprietary code and designs on FPGAs could result in the compromise of sensitive information if the FPGA device was physically relinquished or remotely accessible to adversaries seeking to obtain the information. Although multiple defensive measures have been implemented (and overcome), the possibility exists to create a secure design through the implementation of polymorphic Dynamically Reconfigurable FPGA (DRFPGA) circuits. Using polymorphic DRFPGAs removes the static attributes from their design; thus, substantially increasing the difficulty …

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Optimization Of The Metamorphic Development Process Via The Genetic Algorithm, Keith Daniel Joseph Goren Mar 2008

Optimization Of The Metamorphic Development Process Via The Genetic Algorithm, Keith Daniel Joseph Goren

Theses and Dissertations

This main investigation of this thesis was the integration of the metamorphic development process with a genetic algorithm in order to optimize the metamorphic development process. Since the origin of the metamorphic development process, there has been a need for the user to input parameters in order to coax structural development to obtain an optimum structure. By utilizing the genetic algorithm to manipulate this input information, this new marriage of the metamorphic development process and the genetic algorithm can save time and computation for the user of the program. It was found that the genetic algorithm with the metamorphic development …

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Behavior-Based Power Management In Autonomous Mobile Robots, Charles A. Fetzek Mar 2008

Behavior-Based Power Management In Autonomous Mobile Robots, Charles A. Fetzek

Theses and Dissertations

Current attempts to prolong the life of a robot on a single battery charge focus on lowering the operating frequency of the onboard hardware, or allowing devices to go to sleep during idle states. These techniques have much overhead and do not come built in to the underlying robotic architecture. In this thesis, battery life is greatly extended through development of a behavior-based power management system, including a Markov decision process power planner, thereby allowing future robots increased time to operate and loiter in their required domain. Behavior-based power management examines sensors needed by the currently active behavior set and …

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Improvement Of Ecm Techniques Through Implementation Of A Genetic Algorithm, James D. Townsend Mar 2008

Improvement Of Ecm Techniques Through Implementation Of A Genetic Algorithm, James D. Townsend

Theses and Dissertations

This research effective effort develops the necessary interfaces between the radar signal processing components and an optimization routine, such as genetic algorithms, to develop Electronic Countermeasure (ECM) waveforms under a Hardware-in-the-Loop (HILS) architecture. The various ECM waveforms are stored in an ECM library, where an operator selects the desired function to use against a particular system. This optimization works with modular components, compared to previous research that embedded a genetic algorithm into the Range Gate Pull-off (RGPO) waveform optimization loop, which can be interchanged based upon the operator's desired hardware/ software testing setup. The ECM library's first entries contain the …

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Exploitation Of Self Organization In Uav Swarms For Optimization In Combat Environments, Dustin J. Nowak Mar 2008

Exploitation Of Self Organization In Uav Swarms For Optimization In Combat Environments, Dustin J. Nowak

Theses and Dissertations

This investigation focuses primarily on the development of effective target engagement for unmanned aerial vehicle (UAV) swarms using autonomous self-organized cooperative control. This development required the design of a new abstract UAV swarm control model which flows from an abstract Markov structure, a Partially Observable Markov Decision Process. Self-organization features, bio-inspired attack concepts, evolutionary computation (multi-objective genetic algorithms, differential evolution), and feedback from environmental awareness are instantiated within this model. The associated decomposition technique focuses on the iterative deconstruction of the problem domain state and dynamically building-up of self organizational rules as related to the problem domain environment. Resulting emergent …

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Conceptual Study Of Rotary-Wing Microrobotics, Kelson D. Chabak Mar 2008

Conceptual Study Of Rotary-Wing Microrobotics, Kelson D. Chabak

Theses and Dissertations

This thesis presents a novel rotary-wing micro-electro-mechanical systems (MEMS) robot design. Two MEMS wing designs were designed, fabricated and tested including one that possesses features conducive to insect level aerodynamics. Two methods for fabricating an angled wing were also attempted with photoresist and CrystalBond™ to create an angle of attack. One particular design consisted of the wing designs mounted on a gear which are driven by MEMS actuators. MEMS comb drive actuators were analyzed, simulated and tested as a feasible drive system. The comb drive resonators were also designed orthogonally which successfully rotated a gear without wings. With wings attached …

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Collision Avoidance For Uavs Using Optic Flow Measurement With Line Of Sight Rate Equalization And Looming, Paul J. Shelnutt Mar 2008

Collision Avoidance For Uavs Using Optic Flow Measurement With Line Of Sight Rate Equalization And Looming, Paul J. Shelnutt

Theses and Dissertations

A series of simplified scenarios is investigated whereby an optical flow balancing guidance law is used to avoid obstacles by steering an air vehicle between fixed objects/obstacles. These obstacles are registered as specific points that can be representative of features in a scene. The obstacles appear in the field of view of a single forward looking camera. First a 2-D analysis is presented where the rate of the line of sight from the vehicle to each of the obstacles to be avoided is measured. The analysis proceeds by initially using no field of view (FOV) limitations, then applying FOV restrictions, …

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Electrically Steerable Diffraction Gratings For Hyperspectral Imaging: A Microelectromechanical System Design And Fabrication, Saban Atinc Delican Mar 2008

Electrically Steerable Diffraction Gratings For Hyperspectral Imaging: A Microelectromechanical System Design And Fabrication, Saban Atinc Delican

Theses and Dissertations

The current research is focused on the design and fabrication of an electrically programmable diffraction grating using standard micro electro mechanical systems (MEMS) technology. The goal is to design a beam steering element required to build very small hyperspectral imaging (HSI) sensors. The diffraction grating will be used to perform beam-dispersion - a critical step in the imaging process. The proposed transmissive diffraction grating based approach will minimize the overall size and the number of components in the physical design of the hyperspectral imagers, thereby enabling us to exploit the traditional advantages of MEMS such as increased reliability, smaller size, …

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Molecular Characterization Of Wetland Soil Bacterial Communities In Constructed Mesocosms, Elisabeth M. Leon Mar 2008

Molecular Characterization Of Wetland Soil Bacterial Communities In Constructed Mesocosms, Elisabeth M. Leon

Theses and Dissertations

16S rRNA gene analysis was performed on soil samples from a subsurface flow mesocosm experiment, mimicking a constructed wetland. Three typical wetland species of plant were used in nine of the columns and three columns were unplanted controls. Analyses showed that plant presence, plant species, and depth did not have a significant effect on microbial community composition. However, richness analyses illustrated that plant presence had a positive effect on richness, plant species analyses indicated that there was evidence that plant species affected richness in a significant manner, and lastly richness was negatively affected in the bottom depth for the control …

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