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Using A Multiobjective Approach To Balance Mission And Network Goals Within A Delay Tolerant Network Topology, Anthony L. Larweck Mar 2009

Using A Multiobjective Approach To Balance Mission And Network Goals Within A Delay Tolerant Network Topology, Anthony L. Larweck

Theses and Dissertations

This thesis investigates how to incorporate aspects of an Air Tasking Order (ATO), a Communications Tasking Order (CTO), and a Network Tasking Order (NTO) within a cognitive network framework. This was done in an effort to aid the commander and or network operator by providing automation for battlespace management to improve response time and potential inconsistent problem resolution. In particular, autonomous weapon systems such as unmanned aerial vehicles (UAVs) were the focus of this research This work implemented a simple cognitive process by incorporating aspects of behavior based robotic control principles to solve the multi-objective optimization problem of balancing both …

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Unified Behavior Framework In An Embedded Robot Controller, Stephen S. Lin Mar 2009

Unified Behavior Framework In An Embedded Robot Controller, Stephen S. Lin

Theses and Dissertations

Robots of varying autonomy have been used to take the place of humans in dangerous tasks. While robots are considered more expendable than human beings, they are complex to develop and expensive to replace if lost. Recent technological advances produce small, inexpensive hardware platforms that are powerful enough to match robots from just a few years ago. There are many types of autonomous control architecture that can be used to control these hardware platforms. One in particular, the Unified Behavior Framework, is a flexible, responsive control architecture that is designed to simplify the control system’s design process through behavior module …

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Modeling Of Aircraft Deicing Fluid Induced Biochemical Oxygen Demand In Subsurface-Flow Constructed Treatment Wetlands, William J. Mclaughlin Mar 2009

Modeling Of Aircraft Deicing Fluid Induced Biochemical Oxygen Demand In Subsurface-Flow Constructed Treatment Wetlands, William J. Mclaughlin

Theses and Dissertations

Aircraft deicing is vital to safe operation in cold weather environments. Unfortunately, release of glycol-based aircraft deicing fluids (ADF) to waterways adjacent to airfields poses a significant environmental threat. The deicing fluids used at DoD airfields impart a high biochemical oxygen demand (BOD) when they enter waterways. The currently accepted conventional treatment is collection and transport of ADF-laden storm water to a publicly owned treatment works. The volume and BOD concentrations in the storm water often make this type of treatment impractical. Subsurface flow constructed treatment wetlands have been demonstrated to be effective in attenuating ADF-induced BOD. The models currently …

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Satellite Reentry Control Via Surface Area Amplification, Salvador Alemán Mar 2009

Satellite Reentry Control Via Surface Area Amplification, Salvador Alemán

Theses and Dissertations

This project endeavors to find whether it is feasible to use an increase in surface area as a way of increasing the drag on an orbiting object, thus decreasing its orbital lifetime. The surface area increase can be achieved by an apparatus that deploys a balloon. The balloon will act as a parachute that will decrease the potential energy of the object through atmospheric drag. This is most effective by objects that reach the Low Earth altitudes of less than 500 kilometers, where an object is encountering a firmer atmospheric density. The project is carried out through propagating three different …

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Phosphorus Fractionation And Distribution Across Delta Of Deer Creek Reservoir, Warren C. Casbeer Mar 2009

Phosphorus Fractionation And Distribution Across Delta Of Deer Creek Reservoir, Warren C. Casbeer

Theses and Dissertations

Eutrophication of reservoir systems, which causes deterioration of water quality through increased algal growth, is detrimental to our sustainable water supply and additionally impairs other beneficial reservoir uses. Limiting the amount of phosphorus (P) entering the system has been the key management tool for this problem, as P is the main limiting nutrient for plant and algal growth. These efforts have focused on controlling input of P from point sources, such as effluents from wastewater treatment plants, dairies, and industrial factories. Even in systems (such as reservoirs) with significantly reduced external P loading, however, there has been continued eutrophication and …

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Parental Competencies Of Juvenile Probationers And Adherence To Curt Sanctions And Recidivism Rates, Amy Cook Mar 2009

Parental Competencies Of Juvenile Probationers And Adherence To Curt Sanctions And Recidivism Rates, Amy Cook

Theses and Dissertations

The purpose of this exploratory study was to further investigate the notion of parental competencies through the use of the Juvenile Offender Parent Questionnaire as previously developed by Rose and colleagues (2004). The parent questionnaire was administered to 88 parents of juvenile probationers placed on probation in a Virginia county. Exploratory Factor Analysis revealed an eight-factor solution: parental exasperation, parental resignation, mistrust of the juvenile justice system, shame over parenting efficacy, parental monitoring, fear of the child, parent perceptions of child’s exposure to violence, and anger towards child. Regression analyses indicate that parental exasperation and parental resignation were not significant …

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The Social Strategies And Goals Of Children With Language Impairment And Typically Developing Children, Veronica Gardner Mar 2009

The Social Strategies And Goals Of Children With Language Impairment And Typically Developing Children, Veronica Gardner

Theses and Dissertations

Past research has indicated that children with language impairment (LI) struggle more than children with typical language in their social interactions (Fujiki, Brinton, & Todd, 1999). The purpose of this study was to determine if the social strategies and goals of children with LI varied from those of children with typically developing language. A social goals questionnaire was used to determine the strategies the children verbally indicated that they would use. The children were then asked why they would use the selected strategy. The responses were then separated into goal categories. A chi-square analysis indicated that children with LI varied …

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Fremont Site Distribution In The Upper Escalante River Drainage, Deborah C. Harris Mar 2009

Fremont Site Distribution In The Upper Escalante River Drainage, Deborah C. Harris

Theses and Dissertations

A Fremont site distribution model for the Grand Staircase-Escalante National Monument during the period A.D. 500—1050/1100 posits that the Fremont subsistence strategy (seasonal mobility with dependence on both agriculture and hunting/foraging) is reflected by a site pattern of low-investment, seasonal or short-term habitation sites and isolated storage facilities at "lowland" elevations, and high-investment, long-term residence sites at "upland" elevations (McFadden 1998, 2000). This research assesses the model to evaluate its general precision, looking particularly at its success in modeling site locations for long-term residential versus seasonal/short-term habitation sites. A database including more than 400 Fremont sites was created to evaluate …

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Evaluation Of An Innovative Technology For Treatment Of Water Contaminated With Perchlorate And Organic Compunds, Maureen A. Downen Mar 2009

Evaluation Of An Innovative Technology For Treatment Of Water Contaminated With Perchlorate And Organic Compunds, Maureen A. Downen

Theses and Dissertations

Drinking water sources contaminated with both perchlorate and organic compounds have frequently been found in the U.S. Tailored granular activated carbon (T-GAC) is an innovative technology that is being evaluated to determine if it can more cost effectively remove perchlorate than conventional technologies. A question that has been raised is whether T-GAC can economically treat perchlorate-contaminated water that also has organic co-contaminants present. During a field study, trichloroethylene, an organic compound, and perchlorate were successfully removed by adsorption using a T-GAC/GAC system. These results motivated development of a model that could be applied to predict the cost and performance of …

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Compact Trench Based Bend And Splitter Devices For Silicon-On-Insulator Rib Waveguides, Yusheng Qian Mar 2009

Compact Trench Based Bend And Splitter Devices For Silicon-On-Insulator Rib Waveguides, Yusheng Qian

Theses and Dissertations

Bends and splitters are typically the fundamental limiting waveguide components in reducing the size of planar lightwave circuits (PLCs) based on waveguides that have a low core/clad refractive index contrast, such as silicon-on-insulator (SOI) rib waveguides. This dissertation presents a solution to this problem in the form of trench-based bends (TBBs) and trench-based splitters (TBSs). Emphasis is placed on experimental demonstration of these components and their integration into practical devices exhibiting significant size reduction. First, a compact and low loss silicon-on-insulator rib waveguide 90◦ TBB is demonstrated based on an etched vertical interface and total internal reflection (TIR) realized by …

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French Laïcité And The Popularity Of The Pacs, Ashley Gaylene Trupp Mattson Mar 2009

French Laïcité And The Popularity Of The Pacs, Ashley Gaylene Trupp Mattson

Theses and Dissertations

Civil unions are currently a divisive issues in the United States. Religion has historically influenced these debates. The French version of civil union, the Pacte Civil de Solidarité (Pacs,) was created in 1999 after seven years of debate. Many have written about the Pacs in the last decade. However, few have explored the direct correlations with France's relationship with Catholicism, her dominant religion that is doctrinally opposed to any sexual relationships outside of marriage. Laïcité has influenced a steady decrease in religiosity among French Catholics. This thesis explores the impact of this religious decline on the creation and surprising popularity …

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A Comparison Of Mathematical Discourse In Online And Face-To-Face Environments, Shawn D. Broderick Mar 2009

A Comparison Of Mathematical Discourse In Online And Face-To-Face Environments, Shawn D. Broderick

Theses and Dissertations

Many studies have been done on the impact of online mathematics courses. Most studies concluded that there is no significant difference in student success between online and face-to-face courses. However, most studies compared "traditional" online and face-to-face courses. Mathematics educators are advocating a shift from traditional courses to student-centered courses where students argue and defend the mathematics under the guidance of the teacher. Now, the differences in online and face-to-face student-centered mathematical courses merit a more in-depth investigation. This study characterized student mathematical discourse in online and face-to-face Calculus lab sections based off of a framework derived from an NCTM …

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Alternating Links And Subdivision Rules, Brian Craig Rushton Mar 2009

Alternating Links And Subdivision Rules, Brian Craig Rushton

Theses and Dissertations

The study of geometric group theory has suggested several theorems related to subdivision tilings that have a natural hyperbolic structure. However, few examples exist. We construct subdivision tilings for the complement of every nonsingular, prime alternating link and all torus links, and explore some of their properties and applications. Several examples are exhibited with color coding of tiles.

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The Role Of Emerging Adult And Parent Financial Behaviors, Criteria And Assistance On The Marital Horizons Of Emerging Adults, Laura Jo Nelson Mar 2009

The Role Of Emerging Adult And Parent Financial Behaviors, Criteria And Assistance On The Marital Horizons Of Emerging Adults, Laura Jo Nelson

Theses and Dissertations

Recent studies indicate that financial independence is important to the transition to adulthood. This study, grounded in a marital horizon theory of emerging adulthood, examines the role of emerging adult and parent financial patterns on emerging adults' marital horizons. Correlations, stepwise-regressions and a MANOVA were conducted using a sample of 403 emerging adults and 326 parents that were recruited from five college sites across the United States. Results demonstrated that significant differences existed between finances and emerging adults' marital horizons. Specifically, emerging adults with higher financial criteria and who received more parental financial assistance were more likely to report not …

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Influence Of Parental Substance Abuse On Substance Use And Psychiatric Severity In Drug-Dependent Pregnant Women, Courtney E. Smith Mar 2009

Influence Of Parental Substance Abuse On Substance Use And Psychiatric Severity In Drug-Dependent Pregnant Women, Courtney E. Smith

Theses and Dissertations

The purpose of this study was to examine the relationship between history of parental substance abuse and substance use and psychiatric severity measures in a sample of treatment-seeking, pregnant women who meet DSM-IIIR criteria for lifetime opioid and cocaine abuse and/or dependence (N=260). The study examined whether a dose-response relationship was observed between number of parents affected by substance use problems (0, 1, and 2) and degree of women’s substance use and psychiatric severity. Results did not support a dose-response relationship between density of parental problems and substance use and psychiatric severity. However, some differences in severity were seen at …

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Value-Driven Enterprise Architecture Score: Evaluation Applied To Joint Force Protection Future State Design, Larry D. Cotton, Gary A. Haase Mar 2009

Value-Driven Enterprise Architecture Score: Evaluation Applied To Joint Force Protection Future State Design, Larry D. Cotton, Gary A. Haase

Theses and Dissertations

This research presents a methodology to evaluate the quality of a system's architecture using principles drawn from Value-Focused Thinking (VFT) and resulting in a Value-Driven Enterprise Architecture Score (VDEA-Score). This is an overall numerical architecture quality score useful to a system's management team to identify the advantages and disadvantages of a system design and associated architecture documentation or to track its quality across discrete evaluation epochs. This effort determined which aspects of the architecture are most valuable to the stakeholder in the areas of (1) the system effectiveness values (quality of the instantiated system being represented and its ability to …

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Waste Vegetable Oil As An Alternative Fuel For Diesel Vehicles, Harvey S. Gaber Mar 2009

Waste Vegetable Oil As An Alternative Fuel For Diesel Vehicles, Harvey S. Gaber

Theses and Dissertations

Alternative fuels have become a hot topic in the news as the cost of oil remains volatile. Questions of whether acquiring alternative fuels are worth the cost, logistics, and political implications are being asked. A possible solution may be currently thrown away by Wright Patterson Air Force Base’s (WPAFB) dining establishments in the form of Waste Vegetable Oil (WVO). This study researched the benefits and costs of pursuing the installation of a WVO to Straight Vegetable Oil fuel processing center and using the fuel to power some of the base’s diesel vehicles. A pilot program was fielded utilizing the Wright …

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Probabilistic Estimation Of Rare Random Collisions In 3-Space, Timothy Holzmann Mar 2009

Probabilistic Estimation Of Rare Random Collisions In 3-Space, Timothy Holzmann

Theses and Dissertations

A study of risk assessment for artillery fire randomly colliding with fixed wing aircraft is presented. The research lends itself to a general study of collision models. Current models of object collisions fall under one of three categories: the historical model, the gas particle model, and the satellite model. These three vary in data requirements and mathematical representation of the impact event. The gas particle model is selected for its flexibility and robust estimation. However, current mathematical development in the literature does not include certain spatial and dynamic components necessary for a general encounter (collision) model. These are derived in …

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In Vitro Toxicity Of Silver Nanoparticles In Human Lung Epithelial Cells, Christina R. Kearns Mar 2009

In Vitro Toxicity Of Silver Nanoparticles In Human Lung Epithelial Cells, Christina R. Kearns

Theses and Dissertations

Nanotechnology is quickly becoming incorporated into everyday products and uses. Silver nanoparticles, specifically, are being used in commercial products, to include aerosols. The purpose of this research was to determine whether silver nanoparticles are toxic to human lung epithelial cells. Different types (coated vs. uncoated), concentrations (10, 50, 100, and 200 µg/mL) and sizes (coated 5 and 80nm, uncoated 10 and 80nm) of silver nanoparticles were used during this study. Toxicity measurements were completed through in vitro techniques. Another study was also completed on toxicity mechanisms by measuring the reactive oxygen species (ROS) generated. Results showed that silver nanoparticles induce …

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The Use Of Spider Webs As Passive Bioaerosol Collectors, Daniel I. Mattei Mar 2009

The Use Of Spider Webs As Passive Bioaerosol Collectors, Daniel I. Mattei

Theses and Dissertations

In this experiment, spider webs demonstrated their suitability as passive bioaerosol collectors. For spider webs to be considered suitable passive collectors webs had to satisfy three basic conditions; (1) collection of microorganisms without discrimination based on species or size, (2) collection under variable environmental conditions, and (3) saturation avoidance in the presence of strong microbial launching sources. Four field sampling locations were used, a waste water treatment facility, a commercial garden center, a secluded state park area, and a parking garage. Microscopy cover glass slides were used as the collection instrument. The methodology assured sterility during collection and promoted in …

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Modeling Thermal Inactivation Of Bacillus Spores, Emily A. Knight Mar 2009

Modeling Thermal Inactivation Of Bacillus Spores, Emily A. Knight

Theses and Dissertations

This research models and analyzes methods to damage Bacillus anthracis spores through heat treatment. AFIT researchers have developed methods to characterize the effects of heating spores to high temperatures and for short durations similar to the thermal pulse of conventional weapon detonation. This research models the current experiment and evaluates the rate of thermal diffusion throughout the spores. A micro-model of the effects of dry and wet heating on a spore is presented. Heating a spore energizes adsorbed, absorbed, and chemically bound water molecules. These energized molecules have greater mobility within the spore, as well as between the spore and …

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Estimation Of Weapon Yield From Inversion Of Dose Rate Contours, Buckley E. O'Day Iii Mar 2009

Estimation Of Weapon Yield From Inversion Of Dose Rate Contours, Buckley E. O'Day Iii

Theses and Dissertations

This research studies the uncertainty in yield estimation from inversion of dose rate contours. The Hazard Prediction and Assessment Capability (HPAC) and a simple FORTRAN95 based Fallout Deposition Code (FDC) are used to recreate dose rate contours from historic nuclear tests. Fallout footprints from six atomic tests are recreated using balloon wind soundings and high resolution mesoscale weather reanalysis data. Dose rate contour plots are created for different yields for a single set of weather conditions. Dose rate contours are compared to determine uncertainty in yield estimation from inversion of dose rate contour plots. Results of these dose rate recreations …

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Thermal Inactivation Of Bacillus Anthracis Using Laser Irradiation Of Micro-Etched Platforms, Jeffrey B. Bacon Mar 2009

Thermal Inactivation Of Bacillus Anthracis Using Laser Irradiation Of Micro-Etched Platforms, Jeffrey B. Bacon

Theses and Dissertations

The purpose of this research was to determine the probability of kill for a thermal inactivation strategy for use against biological agents; specifically the resilient endospore of Bacillus anthracis (Ba). The effort focused on short durations (milliseconds to several seconds) and temperatures (300 to 1300 K) simulating the periphery effects after an explosion generated by conventional munitions. For an improved statistical counting, applied microlithography techniques were used to produce micro-etched glass platforms consisting of 532 circular sample wells, evenly spaced. Small carbon black radiators, which provide fast heating/cooling rate and confined temperature distribution, were produced by populating the etched wells …

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Controlling Hazardous Noise And Dust Within The Industrial Workforce Using A Simple Barrier, Daniel D. Sweeney Mar 2009

Controlling Hazardous Noise And Dust Within The Industrial Workforce Using A Simple Barrier, Daniel D. Sweeney

Theses and Dissertations

The United States Air Force (USAF) has experienced a dramatic increase in hearing loss claims since 2001. Additionally, many operations within the USAF expose personnel to hazardous dust levels. Likewise, the US mining industry has difficulties controlling hazardous noise and dust exposures in underground mining. Specifically, studies have shown that coal mine longwall shearer operators are routinely exposed to noise levels at 151 percent of the allowable dose and approximately 20 percent exceed regulatory dust levels. An above ground full scale model of the underground shearing operation was developed to test the feasibility of mounting a permanent partial barrier on …

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An Exploratory Social Network Analysis Of Military And Civilian Emergency Operation Centers Focusing On Organization Structure, Joseph D. Legradi Mar 2009

An Exploratory Social Network Analysis Of Military And Civilian Emergency Operation Centers Focusing On Organization Structure, Joseph D. Legradi

Theses and Dissertations

The purpose of this research was to explore how United States Air Force Emergency Operation Centers (EOC) compare to civilian EOCs with respect to their task-based social networks and decision making social networks. Multiple measures were explored to understand the networks, which included analyzing key metrics of the network such as closeness centrality and betweenness centrality, centralization of the network, and comparison of structural holes within the networks. These measures were then used to suggest improvements for the organizations to improve performance and more importantly, interoperability. The results of the study showed that in this data set there were several …

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A Metagenomic Analysis Of Microbial Contamination In Aviation Fuels, Jerrod P. Mccomb Mar 2009

A Metagenomic Analysis Of Microbial Contamination In Aviation Fuels, Jerrod P. Mccomb

Theses and Dissertations

Microbial contamination in aviation fuel arises due to the impracticality of keeping fuel tanks sterile and the inevitable presence of water from condensation. Microbial contaminants in aviation fuels are a concern because of their potential to degrade the fuel, accelerate corrosion within the fuel tank, and threaten flight safety. This research aids in mitigating those problems by comprehensively characterizing the microbial communities affecting aviation fuels. Advances in molecular biological techniques have allowed for the identification of microorganisms which were not identified by the traditional culture-based methodologies used in previous studies. This study employed a molecular method known as 16S rDNA …

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Heterogeneity Effects In Plutonium Contaminated Soil, Orlando M. Chaparro Mar 2009

Heterogeneity Effects In Plutonium Contaminated Soil, Orlando M. Chaparro

Theses and Dissertations

In 1960 at the McGuire Air Force Base, New Egypt, New Jersey a helium tank ruptured causing a fire to ignite a nearby nuclear tipped Boeing Michigan Aeronautical Research Center (BOMARC) missile. During the fire the weapons grade plutonium (Pu- 239, Pu-240, and Pu-241) ignited and was released into the surrounding area, due to both firefighting efforts, where high pressure water was used to put out the fire, as well as smoke that deposited plutonium as oxidized particles in the surrounding area (Cicotte, 2007). This study investigates the heterogeneity of the distributed plutonium contamination in the McGuire Air Force Base …

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Production And Characterization Of High Repetition Rate Terahertz Radiation In Femtosecond-Laser-Induced Air Plasma, Michael L. Dexter Mar 2009

Production And Characterization Of High Repetition Rate Terahertz Radiation In Femtosecond-Laser-Induced Air Plasma, Michael L. Dexter

Theses and Dissertations

The purpose of this research was to produce and characterize high repetition rate terahertz radiation in ionized air plasma. An 800 nanometer, 50 femtosecond, 0.35 Watt, 40 KHz, pulsed Ti:Sapphire laser system was used as the source infrared beam. This beam was focused onto a second harmonic generation crystal to produce a collinear, perpendicularly polarized secondary beam at 400 nm. After realigning the polarization of the fundamental to the second harmonic and compensating for group velocity dispersion introduced by the optics, both beams were recombined and focused by a 3.75 cm focal length mirror to form an air plasma. An …

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An Evaluation Of Growth Models As Predictive Tools For Estimates At Completion (Eac), Elizabeth N. Trahan Mar 2009

An Evaluation Of Growth Models As Predictive Tools For Estimates At Completion (Eac), Elizabeth N. Trahan

Theses and Dissertations

Efficient decision making mandates the accuracy of forecasted estimations of a contract's final value known within Earned Value Management (EVM) as the Estimates at Completion (EAC). Our research evaluates the prospect of nonlinear growth modeling as an alternative to the current predictive tools used for calculating EAC, such as the Cost Performance Index (CPI), the Schedule Cost Index (SCI), and the Composite Index methods. Our study uses the Gompertz growth curve to produce three EAC Models based on contract phase: A Production Model, a Development Model, and a Combined Model. Contract Performance Report (CPR) data are used to develop the …

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Micro-Scale Flapping Wings For The Advancement Of Flying Mems, Nicholas R. Coleman Mar 2009

Micro-Scale Flapping Wings For The Advancement Of Flying Mems, Nicholas R. Coleman

Theses and Dissertations

This research effort presents conceptual micro scale air vehicles whose total dimensions are less than one millimeter. The initial effort was to advance the understanding of micro aerial vehicles at sub-millimeter dimensions by fabricating and testing micro scale flapping wings. Fabrication was accomplished using a surface micromachining process called PolyMUMPs™. Both rigid mechanical structures and biomimetic devices were designed and fabricated as part of this effort. The rigid mechanical structures focused on out of plane deflections with solid connections and assembling a multiple hinge wing structure through the aid of residual stress. These devices were actuated by double hot arm …

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