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Design, Analysis And Development Of A Morphable Wing Structure For Unmanned Aerial Vehicle Performance Augmentation, Abhijit Hiraman Supekar May 2007

Design, Analysis And Development Of A Morphable Wing Structure For Unmanned Aerial Vehicle Performance Augmentation, Abhijit Hiraman Supekar

Mechanical and Aerospace Engineering Theses - Archive

In this research, we propose mechanisms to continuously morph a wing from a lower aspect ratio to a higher and to further extremities of a gull and an inverted-gull configuration. The mechanism comprises of a linear actuator for the extension of the wing and the servo motors to obtain the gull and inverted gull configurations. The initial design and preliminary finite element representation using 3D-beams and plates in ANSYS Classic were the benchmarks to proceed for the detailed structural analysis of the complete wing in ANSYS Workbench. An elliptical pressure distribution at the quarter cord is assumed for the linear …

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For The Greater Good Or Greed? Redistributing Private Space Through Eminent Domain Power: Relocating The Dallas Cowboys Stadium To Arlington, Texas, Kim Probasco May 2007

For The Greater Good Or Greed? Redistributing Private Space Through Eminent Domain Power: Relocating The Dallas Cowboys Stadium To Arlington, Texas, Kim Probasco

Public Affairs Theses - Archive

The use of eminent domain power to take private land for private use continues to grow in the United States. Many American people lost their homes or businesses to city and council driven economic development in low-income neighborhoods. This paper seeks to explore the social implications that eminent domain power has on residents and examines power that is used by cities and councils to create economic development through the taking of land in low-income communities. I explore these issues through a case study of the Dallas Cowboys Stadium relocation to Arlington, Texas utilizing discourse analysis. I use Henri Lefebvre's conceptual …

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Design And Implementation Of A Feedback Linearizing Controller And Kalman Filter For A Magnetic Levitation System, John Andrew Henley May 2007

Design And Implementation Of A Feedback Linearizing Controller And Kalman Filter For A Magnetic Levitation System, John Andrew Henley

Mechanical and Aerospace Engineering Theses - Archive

The principal investigation undertaken in this research is the development and subsequent implementation of a feedback linearizing nonlinear controller and extended Kalman filter for a laboratory-based Magnetic Levitation (Maglev) device. The Maglev hardware is both highly nonlinear and open-loop unstable in its dynamic response. The control and estimation scheme proposed in this work is first validated using an increasingly sophisticated level of simulations. The control and estimation algorithm had the sensor noise identified using hardware data. Then, the plant noise covariance is tuned using both on-line and off-line hardware data. Additionally, the output of the nonlinear controller is then mapped …

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Experimental Study Of Laminated Composite Tubes Under Bending, Puneet Saggar May 2007

Experimental Study Of Laminated Composite Tubes Under Bending, Puneet Saggar

Material Science and Engineering Theses - Archive

Bending stiffness of laminated composite tubes was determined experimentally using four-point bending test. The experimental results were compared with the results obtained by the laminated plate and smear property approaches. The results indicate that experimental values are closer to prediction of the laminated plate approach compared to smear property approach. Effects of tube radius and stacking sequence and fiber orientation of the walled thickness laminate on bending stiffness and strength of composite tubes were studied. Fracture analysis was conducted to investigate the failure process of the tube. Both techniques of x-ray radiography and optical microscopy were used in this study. …

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A Generic Stability And Control Tool For Flight Vehicle Conceptual Design: Aeromech Software Development, Gary John Coleman May 2007

A Generic Stability And Control Tool For Flight Vehicle Conceptual Design: Aeromech Software Development, Gary John Coleman

Mechanical and Aerospace Engineering Theses - Archive

During the conceptual design (CD) phase, various solution concepts must, and should, be explored to select the best flight vehicle size and configuration in order to meet the mission requirements. As the aerospace industry advances novel aerospace flight vehicle configurations promising larger operational performance and overall efficiency, demanding integrated flight vehicles like the flying wing configuration (FWC) or blending wing body (BWB) are under investigation. Some of these novel configurations rely on novel control effectors (CE) and complex flight control systems in order to obtain the desired performance objectives. Clearly, stability and control plays an important roll in the design …

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Peer Effects In Sports: Evidence From Ncaa Relay Teams, Lisa Elin Haglund May 2007

Peer Effects In Sports: Evidence From Ncaa Relay Teams, Lisa Elin Haglund

Economics Theses - Archive

This paper investigates whether disparity in team member quality impacts team production using NCAA 4x400m relay teams. As a measure of quality I use the team member's individual rankings. The net peer effects are estimated on a team level rather than on an individual level, and are found to have both an absolute and relative negative effect on the team performance. This paper is differentiated from the existing literature by using a direct measure of quality compared to other indirect measures of worker quality such as wages. The evidence provided herein shows that a greater disparity in team member quality …

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Experimental Studies To Address Strengths Of Limestone Cores, Sulfate Heave Problems In Limestone Cores And Tunnel Lining, Vivekananda Chikyala May 2007

Experimental Studies To Address Strengths Of Limestone Cores, Sulfate Heave Problems In Limestone Cores And Tunnel Lining, Vivekananda Chikyala

Civil Engineering Theses - Archive

Sulfate induced heave is a common scenario in tunnels located on sedimentary rocks containing Pyrites. Pyrite oxidation produces Gypsum which is a major source of natural sulfates. DART NC -1B tunnel is located in Dallas, north Texas. Dallas is located on sedimentary rocks with high Pyrite content and has a history of sulfate induced heave problems in several projects. In spring 2005 & 2006, the shotcrete liner in DART NC-1B tunnel showed cracking associated with water leaks. Considering the local geology and the history of the tunnel, researchers at The University of Texas at Arlington (UTA) suspected probable occurrence of …

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Performance Studies On Rigid Pavement Sections Built On Stabilized Sulfate Soils, Deepti Vasudev May 2007

Performance Studies On Rigid Pavement Sections Built On Stabilized Sulfate Soils, Deepti Vasudev

Civil Engineering Theses - Archive

Soils of Southeast Arlington are highly expansive and rich in sulfates. They undergo sulfate induced heaving when traditional calcium based stabilizers are used for soil stabilization (Puppala et al. 1998). Traditional stabilizers do not provide effective solution since they are known to induce heaving, termed in the literature as sulfate induced heaving (Hunter, 1988). Both swelling and softening of these soils rich in sulfates induce considerable damage to overlying pavement infrastructure. Typically, high sulfate soils treated with calcium based stabilizers form ettringite mineral. Ettringite undergoes heaving when hydrated (Hunter, 1988; Puppala et al. 2001). Since this sulfate-induced heave is caused …

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Tissue And Vascular Oxygenation Dynamics Determined By Optical Approaches And Mri, Mengna Xia May 2007

Tissue And Vascular Oxygenation Dynamics Determined By Optical Approaches And Mri, Mengna Xia

Bioengineering Dissertations - Archive

Tumor oxygenation is a crucial factor to determine the efficiency of non-surgery therapy, such as radiotherapy and chemotherapy. Therefore, various approaches have been applied to tumor in order to improve the tumor oxygen level. Breathing oxygenrich gas with normobaric or hyperbaric pressure has been demonstrated to overcome hypoxia, but with marginal success. Therefore, the outcome would be improved greatly, if the responsive tumors were identified a priori. Two non-invasive techniques were applied to monitor tumor oxygenation dynamics simultaneously when rats were exposed to hyperoxic gas intervention. 19F MRI provides tumor tissue oxygen tension (pO2) images, while Near Infrared Spectroscopy (NIRS) …

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Effects Of A Debonding Flaw Size And Location On The Flexural Performance Of Cfrp Retrofitted Steel Sections, Sharad C. Choudhary May 2007

Effects Of A Debonding Flaw Size And Location On The Flexural Performance Of Cfrp Retrofitted Steel Sections, Sharad C. Choudhary

Civil Engineering Theses - Archive

In US there are several thousand steel bridges at present. Out of them many bridges are at various level of advance deteriorations due to many years of service life and environmental factors. These bridges cannot be fully replaced so retrofitting is the best choice .Earlier steel plates were used. With introduction of FRP in 1960.It is replacing the steel plates as they are lighter in weight and can be made stronger than steel. While installation of these FRP some kinds of Flaws are encountered. The variation of strength of carbon fiber reinforced laminate used for structural repair or strengthening containing …

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A Communication-Centered Approach To Leadership: The Relationship Of Interpersonal Communication Competence To Transformational Leadership And Emotional Intelligence, Marilyn Macik-Frey May 2007

A Communication-Centered Approach To Leadership: The Relationship Of Interpersonal Communication Competence To Transformational Leadership And Emotional Intelligence, Marilyn Macik-Frey

Management Dissertations - Archive

Communication is frequently cited as a critical component of leadership. This study takes a significant theoretical departure from that view and embraces the realm of communication as a lens through which we understand leadership. It proposes that leadership is inherently communicative. Communication is viewed as more than a technique or component of leadership, but rather the essence of leadership (Barge, 1994; Hackman & Johnson, 1991; Vickrey, 1995). Communication is almost universally included in the study of leadership (Capowski, 1994; McLean & Weitzel, 1992; Vickrey, 1995), but is not typically viewed as a foundational element or as the central process from …

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Sociolinguistic Cues, Perceived Race, And Employment Selection Outcomes: An Exploration Of The Aversive Racism Framework, Faye K. Cocchiara May 2007

Sociolinguistic Cues, Perceived Race, And Employment Selection Outcomes: An Exploration Of The Aversive Racism Framework, Faye K. Cocchiara

Management Dissertations - Archive

The limited number of available positions to job candidates has led to increased competitiveness among job seekers and the development of new and more efficient employment screening methods by human resources personnel. As a result, job candidates are likely to participate in a telephone interview at some point during the selection process. It is during these interviews that important perceptions about employment potential are made. A number of factors influence perceptions about the future potential of job candidates. In the absence of face-to-face interaction, decision makers may rely on how candidates sound over the telephone to make judgments about the …

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Shades Of Scarlett: Cultural Images Of Historical Southern Women, Gail Nash Tunnell May 2007

Shades Of Scarlett: Cultural Images Of Historical Southern Women, Gail Nash Tunnell

English Theses - Archive

The white antebellum/Civil War-era woman occupies an evolving archetypal status in American cultural consciousness throughout the twentieth century. In 1936, extending a one-hundred year tradition of featuring Southern belles in novels, Margaret Mitchell published Gone with the Wind; in 1996, Charles Frazier published Cold Mountain. Both of these novels offer striking images of the Southern belle as well as the "poor white" Southern woman. My paper will compare the images and interactions of upper and lower class female characters, considering the earlier stereotypical characteristics given to each group, the homosocial relationships between the two groups, and the revision of both, …

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Wireless Sensor Network Testbed: Measurement And Analysis, Rahul Pramod Sawant May 2007

Wireless Sensor Network Testbed: Measurement And Analysis, Rahul Pramod Sawant

Electrical Engineering Theses - Archive

Energy conservation is critical in Wireless Sensor Networks. Replacing or recharging batteries is not an option for sensors deployed in hostile environments. Generally communication electronics in the sensor utilizes most energy. This thesis studies the effect of changing the transmission power and baud rate on transmission distance. Using Shannon channel capacity formula and Log - Distance Path Loss Model, transmission distance is shown to be related to transmit power and baud rate. Extensive empirical readings are taken to confirm the above relation. The path loss exponent got as a result of data fitting is within the acceptable range for wireless …

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Sex Differences In Object Location Memory: Fixed Versus Moving Through Space, Jose Antonio Velarde May 2007

Sex Differences In Object Location Memory: Fixed Versus Moving Through Space, Jose Antonio Velarde

Psychology Theses - Archive

Previous studies suggest that females possess superior object location memory than males. The present study investigated object location memory using both static and dynamic tasks. Additionally, the correlation between object location memory and other variables such as spatial self-rating items, MRT, and 2D:4D was examined. Participants were 136 (70 female and 66 male) undergraduates. Results indicated no significant sex differences in the dynamic task, and only one significant main effect for sex in the static task. As predicted, males rated their sense of direction (SofD), and one-trial directional memory (OTDM) significantly superior to females. Navigation preference also showed significant sex …

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Music Piracy Or A Permanent Passive Revolution, Kevin D. Neely May 2007

Music Piracy Or A Permanent Passive Revolution, Kevin D. Neely

Sociology & Anthropology Theses - Archive

The goal of this thesis is to examine a classic interpretation of Antonio Gramsci's notion of hegemony in the modern era and the emergence of counter-hegemonic forces through technology. The individualization of modern computers and related products, combined with the extreme popularity of file-swapping and social-networking websites (i.e. Napster, KaZaA, MySpace and the brand new YouTube) has completely altered the way the music industry conducts its business and has erased its hegemony over the creation, distribution and profit made from the sale of music. What makes this relationship between an industry and technology specifically different and worthy of our interest …

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Investigations Of The Mechanism Of Dna Cleavage Using Ruthenium Polypyridyl Complexes, Fiona Ongeri May 2007

Investigations Of The Mechanism Of Dna Cleavage Using Ruthenium Polypyridyl Complexes, Fiona Ongeri

Chemistry & Biochemistry Theses - Archive

We have synthesized a ruthenium complex, [(phen)2Ru(tatpp)Ru(phen)2]4+ (P4+), which has been shown to undergo various redox and protonation steps to form different species that can be monitored by UV-Vis spectroscopy. In Chapter 2, the photochemistry of P4+ in the presence and absence of DNA was studied. It was hypothesized that the lifetime (t1/2) of the excited state of P4+, P*, would be extended in the presence of DNA. However, studies conducted showed that the lifetime of P* was diminished in the presence of DNA as compared to P4+ alone. Experiments have also shown that P4+ is capable of damaging DNA …

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Electromagnetically Actuated Devices For Optical Coherence Tomography Applications, Hans P. Hu May 2007

Electromagnetically Actuated Devices For Optical Coherence Tomography Applications, Hans P. Hu

Electrical Engineering Dissertations - Archive

A fast optical scanning device has always been desired for numerous applications such as biomedical imaging, optical communications, and variety of sensing and actuating applications. This dissertation presents a new scanning device operated using external magnetic field with low cost, high function versatility, low field strength, and low power consumption. The design architecture of this device shows its potential for in vivo application with an advantage that addresses the concern of safety. Materials properties are examined using alternating gradient magnetometer(AGM) to verify its performance. Pressure and temperature invariant fabrication processes are implemented to make this device without complicated equipments. The …

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Discrete-Time Control Algorithms And Adaptive Intelligent Systems Designs, Asma Azmi Al-Tamimi May 2007

Discrete-Time Control Algorithms And Adaptive Intelligent Systems Designs, Asma Azmi Al-Tamimi

Electrical Engineering Dissertations - Archive

In this work, approximate dynamic programming (ADP) designs based on adaptive critic structures are developed to solve the discrete-time optimal control problems in which the state and action spaces are continuous. This work considers linear discrete-time systems as well as nonlinear discrete-time systems that are affine in the input. This research resulted in forward-in-time reinforcement learning algorithms that converge to the solution of the Generalized Algebraic Riccati Equation (GARE) for linear systems. For the nonlinear case, a forward-in-time reinforcement learning algorithm is presented that converges to the solution of the associated Hamilton-Jacobi Bellman equation (HJB). The results in the linear …

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Performance Analysis Of Dpsk Systems With Mimo Employing Egc Over Wireless Fading Channels, Iyad Al Falujah May 2007

Performance Analysis Of Dpsk Systems With Mimo Employing Egc Over Wireless Fading Channels, Iyad Al Falujah

Electrical Engineering Dissertations - Archive

The proliferation of digital wireless communication services has increased the congestion of the available radio spectrum. In addition to that, wireless communications are encountered by multipath channel fading. To alleviate the scarcity of the radio spectrum and multipath channel fading, attention in this dissertation is placed on differentially coherent phase shift keying (DPSK) systems with equal gain combining (EGC) diversity reception. DPSK systems are capable of achieving high spectral efficiency with adequate performance over wireless fading channels. Several wireless communication systems have adopted DPSK such as the time division multiple access (TDMA) version of the North American Digital Cellular (NADC) …

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Giovanni Battista Ramusio And The History Of Discoveries: An Analysis Of Ramusio's Commentary, Cartography, And Imagery In Delle Navigationi Et Viaggi, Jerome R. Barnes May 2007

Giovanni Battista Ramusio And The History Of Discoveries: An Analysis Of Ramusio's Commentary, Cartography, And Imagery In Delle Navigationi Et Viaggi, Jerome R. Barnes

History Dissertations - Archive

Giovanni Battista Ramusio was a sixteenth-century Venetian scholar who was very interested in the studies of geography and cartography. Ramusio's keen interest was in the findings of travelers and explorers to all parts of the world during the Age of Discoveries. He is remembered for his compilation of travel narratives entitled Delle Navigationi et Viaggi. Navigationi et Viaggi is a massive work in three volumes that includes a comprehensive collection of travel narratives translated into Italian and published by Giunti in Venice. While this was a major accomplishment, Ramusio's original commentaries on these travels and on the history of exploration …

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Mapping The "Red Menace": British And American News Maps In The Early Cold War Period, 1945-1955, Jeffrey Paul Stone May 2007

Mapping The "Red Menace": British And American News Maps In The Early Cold War Period, 1945-1955, Jeffrey Paul Stone

History Dissertations - Archive

This study examines maps published by the national news press in Britain and the United States from 1945 to 1955. The author analyzes these maps to discern similarities and differences in how British and American news journals put foreign affairs into geographic perspective. Such maps were a valuable medium for educating news readers of developing Cold War geopolitical events, while simultaneously shaping public opinion of foreign places. And they reveal much about a country's world view.

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Investigation Of Information Processing And Cognitive Performance Capacities With Different Instrumentation Configurations, Saju John Mathew May 2007

Investigation Of Information Processing And Cognitive Performance Capacities With Different Instrumentation Configurations, Saju John Mathew

Bioengineering Theses - Archive

The focus of this thesis is the investigation of two new performance capacity tests related to a concept known as "situational awareness": 1) Visual Motor Multitask Performance Capacity (VMMPC) and 2) Visual Auditory Information Processing Dexterity (VAIPD). These represent major components of human information processing and are therefore important in situations ranging from driving and other activities of daily living to occupational and sport tasks. These tests have been recently designed and implemented on a laboratory-based instrument called the BEP I. In the present project, they are implemented on a different, more portable platform that is under development and known …

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Efficacy Of Selected Natural And Synthetic Novel Organic Compounds In Prevention Of Zebra Mussel (Dreissena Polymorpha) Macrofouling By Byssal Attachment Inhibition, Maj-Britt Angarano May 2007

Efficacy Of Selected Natural And Synthetic Novel Organic Compounds In Prevention Of Zebra Mussel (Dreissena Polymorpha) Macrofouling By Byssal Attachment Inhibition, Maj-Britt Angarano

Biology Dissertations - Archive

The invasive, freshwater, bivalve, Dreissena polymorpha (zebra mussel) was introduced to North America in the Great lakes in 1986 and has since spread throughout the waterway of the eastern and central United States and southeastern Canada. This species has imposed escalating economic burdens through its macrofouling of submerged structures and raw water using systems. Increasing restrictions on the chemical mitigation and control methodologies used to prevent their macrofouling, particularly organometallic or oxidizing chemicals, continue to stimulate research efforts to develop effective yet environmentally benign antifouling agents against this species and other macrofouling organisms. The efficacy in inhibiting zebra mussel byssal …

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An Evaluation Of Using Component Mode Synthesis For Structural Models, Richard Lynn Scott May 2007

An Evaluation Of Using Component Mode Synthesis For Structural Models, Richard Lynn Scott

Mechanical and Aerospace Engineering Theses - Archive

Structural analysts have used component mode synthesis (CMS), also known as substructuring, for decades to divide large structural models into smaller, more manageable models, and to reduce the size of the associated mathematical problem. Applying CMS can also reduce the front-end effort to build models, even models that are smaller than those for which CMS has typically been applied. This paper presents an evaluation of the accuracy of two smaller substructured models so that analysts might feel confident in applying CMS to gain the benefits. The evaluation starts with an introduction to CMS. Then, CMS is applied to a small, …

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Control And Simulation Of Relative Motion For Aerial Refueling In Racetrack Maneuver, Eunyoung Kim May 2007

Control And Simulation Of Relative Motion For Aerial Refueling In Racetrack Maneuver, Eunyoung Kim

Mechanical and Aerospace Engineering Theses - Archive

This thesis addresses the problem of controlling the receiver aircraft to achieve a successful aerial refueling. For the performance verification of the controller, a new set of nonlinear, 6-DOF, rigid body equations of motion for the receiver aircraft has been used. The equations are written in terms of state variables that are relative to the reference frame that is attached to, translates and rotates with the tanker aircraft. Furthermore, the nonlinear equations contain the wind effect terms and their time derivatives to represent the aerodynamic coupling involved between the two aircraft. These wind terms are obtained using an averaging technique …

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The Pricing And Determinants Of The Discretionary Component Of Employee Stock Option Value, Chii Shyan Kuo May 2007

The Pricing And Determinants Of The Discretionary Component Of Employee Stock Option Value, Chii Shyan Kuo

Accounting Dissertations - Archive

In this study, I first re-examine the pricing effect of employee stock option (ESO) value. I find a negative association between ESO value and share price, supporting the view that investors view ESO value as an expense of the firm. Further, I find a negative relation between the nondiscretionary component of ESO value (i.e., the expected ESO value) and stock price; this finding indicates that markets view the full ESO value as well as the nondiscretionary component of ESO value as an expense of the firm. Additionally, I find the discretionary component of ESO value (i.e., the unexpected ESO value) …

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Creative Destruction In The Pharmaceutical Industry, Darshak Patel May 2007

Creative Destruction In The Pharmaceutical Industry, Darshak Patel

Economics Theses - Archive

Pharmaceutical firms usually patent any new innovation in terms of the chemicals they use. These innovations are then developed in to drugs which are marketed once approved by FDA. These patents have made and receive citations. Citations made by patents granted today are backward citations and citations a patent will receive in the future are forward citations. This research shows that these patent citations on have a positive effect on market value of Pharmaceutical firms related to the patent. Backward citations do not destroy company rents. In fact, backward citations, illustrate the importance of the cited patent. Multiple citations imply …

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Death Of The American Dream: The Revolutionary Meaning Of Infant Mortality And Mourning In Hannah Webster Foster's The Coquette, Tracey-Lynn Clough May 2007

Death Of The American Dream: The Revolutionary Meaning Of Infant Mortality And Mourning In Hannah Webster Foster's The Coquette, Tracey-Lynn Clough

English Theses - Archive

This thesis explores the broader implications of Hannah Webster Foster's The Coquette through an acknowledgment and assessment of a male audience. The Coquette is a seduction narrative that is linked through form and tradition to Susanna Rowson's Charlotte Temple and William Hill Brown's The Power of Sympathy. However, this project examines the unique strategies Foster employs to make literary meaning outside the space of domesticity. The Coquette's social and political aims can be located in the textual divergences from similar texts of the period. Foster refuses to make narrative apologies, shifts the point of view, and appears determined to more …

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Beyond Good And Evil: Sister Leopolda's Traumatic Will To Power, Alisha Stafford Feitosa May 2007

Beyond Good And Evil: Sister Leopolda's Traumatic Will To Power, Alisha Stafford Feitosa

English Theses - Archive

This is an in-depth analysis of one of Louise Erdrich's most extraordinary characters, Sister Leopolda. I examine Leopolda first as a trauma victim who has suffered the loss of family, witnessed the death and assault of various friends, struggled with her mixed heritage, and fought to establish herself in a world where Indians were rapidly losing their power, their land, and their lives. Second, I use Friedrich Nietzsche's views of power to illustrate how Leopolda's seemingly random and fanatical exploits are actually examples of her will to power. Because of her disturbing past, Leopolda must struggle to survive; her astonishing …

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