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Electronic Theses and Dissertations

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Digital Control Of Half-Bridge Dc-Dc Converters With Current Doubler Rectification, Liangbin Yao Jan 2005

Digital Control Of Half-Bridge Dc-Dc Converters With Current Doubler Rectification, Liangbin Yao

Electronic Theses and Dissertations

DC-DC power converters play an important role in powering telecom and computing systems. Complex systems, including power electronics systems, are increasingly using digital controllers because of the major advancements in digital controllers and DSP as well as there ability to perform sophisticated and enhanced control schemes. In this thesis, the digital controller is investigated for DC-DC converters in high current low voltage applications. For an optimal design of a regulated DC-DC converter, it is necessary to derive a valid model. The current doubler rectified half bridge (CDRHB) DC-DC converter is suitable for high current low voltage applications. In this thesis, …

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Building Information Communication Technology Infrastructures For Economic Development, Domenico Palombo Jan 2005

Building Information Communication Technology Infrastructures For Economic Development, Domenico Palombo

Electronic Theses and Dissertations

This paper analyzes the impact of Information Communication Technology (ICT) Infrastructures on economic development through a statistical analysis of data from Saint Vincent and the Grenadines, and a policy analysis of the Workforce Investment Act and Ben Franklin Technology Partners programs in Pennsylvania. In the analysis of Saint Vincent, significant relationships were found between all aspects of ICT programs and a variety of measures of economic development, with the extent of Internet subscribers showing the greatest impact. The analysis of the Pennsylvania programs found that technology-oriented workforce education programs are only successful when there is a demand for related labor …

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An Optimized Kinetics Model For Oh Chemiluminescence At High Temperatures And Atmospheric Pressures, Joel Hall Jan 2005

An Optimized Kinetics Model For Oh Chemiluminescence At High Temperatures And Atmospheric Pressures, Joel Hall

Electronic Theses and Dissertations

Chemiluminescence from the OH(A-X) transition near 307 nm is a commonly used diagnostic in combustion applications such as flame chemistry, shock-tube experiments, and reacting-flow visualization. Measurements of the chemiluminescent intensity provide a simple, cost-effective, non-intrusive look at the combustion environment. The presence of the ultra-violet emission is often used as an indicator of the flame zone in practical combustion systems, and its intensity may be correlated to the temperature distribution or other parameters of interest. While absolute measurements of the ground-state OH(X) concentrations are well-defined, there is no elementary relation between emission from the electronically excited state (OH*) and its …

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Participation: A Model Of Individual Willingness To Participate In The Transportation Planning Process, Michael Neidhart Jan 2005

Participation: A Model Of Individual Willingness To Participate In The Transportation Planning Process, Michael Neidhart

Electronic Theses and Dissertations

This study sought to identify the key determinants that lead individuals to participate in the transportation planning process. Two models of participation, one for the short-term and another for the long-term, were developed to test whether the key internal and external determinants are responsible for influencing a person's willingness to participate. The data for this study came from a mail-back survey that was administered to a random sample of 570 individuals throughout the State of Florida for a response rate of 37.37 percent. The results indicate that the internal motivational determinants exert more influence on a person's short-term willingness to …

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Transform Based And Search Aware Text Compression Schemes And Compressed Domain Text Retrieval, Nan Zhang Jan 2005

Transform Based And Search Aware Text Compression Schemes And Compressed Domain Text Retrieval, Nan Zhang

Electronic Theses and Dissertations

In recent times, we have witnessed an unprecedented growth of textual information via the Internet, digital libraries and archival text in many applications. While a good fraction of this information is of transient interest, useful information of archival value will continue to accumulate. We need ways to manage, organize and transport this data from one point to the other on data communications links with limited bandwidth. We must also have means to speedily find the information we need from this huge mass of data. Sometimes, a single site may also contain large collections of data such as a library database, …

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The Role Of Domain Expertise And Judgment In Dealing With Unexpected Events, Janeen Kochan Jan 2005

The Role Of Domain Expertise And Judgment In Dealing With Unexpected Events, Janeen Kochan

Electronic Theses and Dissertations

Unexpected events, particularly those creating surprise, interrupt ongoing mental and behavioral processes, creating an increased potential for unwanted outcomes to the situation. Human reactions to unexpected events vary. One can hypothesize a number of reasons for this variation, including level of domain expertise, previous experience with similar events, emotional connotation, and the contextual surround of the event. Whereas interrupting ongoing activities and focusing attention temporarily on a surprising event may be a useful evolutionary response to a threatening situation, the same process may be maladaptive in today's highly dynamic world. The purpose of this study was to investigate how different …

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Recovery Of Hydrogen And Helium From Their Mixtures Using Metal Hydrides, Muzaffer Tonguc Oztek Jan 2005

Recovery Of Hydrogen And Helium From Their Mixtures Using Metal Hydrides, Muzaffer Tonguc Oztek

Electronic Theses and Dissertations

Waste streams of hydrogen and helium mixtures are produced at the Kennedy Space Center during purging of the hydrogen systems and supply lines. This process is done prior to and after hydrogen servicing. The purged waste gases are lost to the atmosphere, resulting in an annual loss of 2 million and 0.1 million standard cubic meters of helium and hydrogen, respectively. Recovery of these gases will have an economic benefit. Metals, alloys, and intermetallics are known to react with hydrogen in favorable conditions; therefore, they have the possibility of serving as separating and recovery agents. In this study, Mg2Ni, VTiNi …

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Seawinds Radiometer Brightness Temperature Calibration And Validation, Mayank Rastogi Jan 2005

Seawinds Radiometer Brightness Temperature Calibration And Validation, Mayank Rastogi

Electronic Theses and Dissertations

The NASA SeaWinds scatterometer is a radar remote sensor which operates on two satellites; NASA's QuikSCAT launched in June 1999 and on Japan's ADEOS-II satellite launched in December 2002. The purpose of SeaWinds is to provide global measurements of the ocean surface wind vector. On QuikSCAT, a ground data processing algorithm was developed, which allowed the instrument to function as a QuikSCAT Radiometer (QRad) and measure the ocean microwave emissions (brightness temperature, Tb) simultaneously with the backscattered power. When SeaWinds on ADEOS was launched, this same algorithm was applied, but the results were anomalous. The initial SRad brightness temperatures exhibited …

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Unified Large And Small Signal Discrete-Space Modeling For Pwm Converters In Ccm, Ehab Hamed Shoubaki Jan 2005

Unified Large And Small Signal Discrete-Space Modeling For Pwm Converters In Ccm, Ehab Hamed Shoubaki

Electronic Theses and Dissertations

In this Thesis a Unified Discrete State-Space Model for power converters in CCM is presented. Two main approaches to arriving at the discrete model are used. The first approach involves an impulse function approximation of the duty cycle modulations of the converter switches , and this approach results in a small signal discrete model. The Second approach is direct and does not involve any approximation of the modulations , this approach yields both a large signal nonlinear discrete model and a linear small signal model. Harmonic analysis of the converter states at steady-state is done for steady-state waveform acquisition , …

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Gender Differences In Characteristics Of Intimate Partner Homicide Offenders, Heather Lynn Wilson Jan 2005

Gender Differences In Characteristics Of Intimate Partner Homicide Offenders, Heather Lynn Wilson

Electronic Theses and Dissertations

This study addresses whether or not male and female intimate partner homicide offenders differ in a variety of characteristics using data from the Chicago Women's Health Risk Study, 1995-1998. Frequencies of male and female intimate partner homicide offender's risk factors were compared to look at how they differ. The areas that were explored were demographics, prior abuse, and the criminal justices response. A number of gender differences were found. Directions for future research pertaining to intimate partner homicide offenders are discussed.

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Alternative Foam Treatments For The Space Shuttle's External Tank, Kirsten Dreggors Jan 2005

Alternative Foam Treatments For The Space Shuttle's External Tank, Kirsten Dreggors

Electronic Theses and Dissertations

The Space Shuttle Columbia accident and the recent excitement surrounding Discovery's return to space brought excessive media attention to the foam products used on the External Tank (ET). In both cases, videos showed chunks of foam or ablative material falling away from the ET during lift off. This led to several years of investigation and research into the exact cause of the accident and potential solutions to avoid the problem in the future. Several design changes were made prior to the return to flight this year, but the ET still shed foam during lift off. Since the Columbia accident, the …

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Background Stabilization And Motion Detection In Launch Pad Video Monitoring, Kaushik Gopalan Jan 2005

Background Stabilization And Motion Detection In Launch Pad Video Monitoring, Kaushik Gopalan

Electronic Theses and Dissertations

Automatic detection of moving objects in video sequences is a widely researched topic with application in surveillance operations. Methods based on background cancellation by frame differencing are extremely common. However this process becomes much more complicated when the background is not completely stable due to camera motion. This thesis considers a space application where surveillance cameras around a shuttle launch site are used to detect any debris from the shuttle. The ground shake due to the impact of the launch causes the background to be shaky. We stabilize the background by translation of each frame, the optimum translation being determined …

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Slope Stability Of Laterite Soil Embankments, Ikiensinma Gogo-Abite Jan 2005

Slope Stability Of Laterite Soil Embankments, Ikiensinma Gogo-Abite

Electronic Theses and Dissertations

Embankments are key elements in the infrastructural development of structures such as dams, bridges, and roads. Residual soils are generally used as fills in the construction of embankments in areas were residual soils such as laterite is the dominant soil types. Laterite soils have the characteristics of losing its shear strength with time and in fully saturated conditions and its properties varies from region to region. The soil property is influenced by the chemical composition and the environment. The binding agent iron oxide in such soils changes its composition with time and in the presence of moisture. Sudden failures of …

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The Legacy Of Andre Smith, Ginny Seibert Jan 2005

The Legacy Of Andre Smith, Ginny Seibert

Electronic Theses and Dissertations

Jules Andre Smith was an architect and an artist with an aspiration to build a retreat where artists could explore and develop new ideas. In the late 1930s, due to the generosity of a benefactor named Mary Louise Curtis Bok, Smith embarked upon an undertaking that fulfilled his ambition. He created a legacy known first as The Research Studio and later as the Maitland Art Center. The intent of this thesis is to document and journey through Smith's legacy, and answer the following two questions: What is the symbolic meaning behind the imagery? Why design six acres of architecture dominated …

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Investigations On Rf Sputter Deposited Sicn Thin Films For Mems Applications, Ravi Todi Jan 2005

Investigations On Rf Sputter Deposited Sicn Thin Films For Mems Applications, Ravi Todi

Electronic Theses and Dissertations

With the rapid increase in miniaturization of mechanical components, the need for a hard, protective coatings is of great importance. In this study we investigate some of the mechanical, chemical and physical properties of the SiCN thin films. Thin films of amorphous silicon carbide nitride (a-SiCxNy) were deposited in a RF magnetron sputtering system using a powder pressed SiC target. Films with various compositions were deposited on to silicon substrate by changing the N2/Ar gas ratios during sputtering. Nano-indentation studies were performed to investigate the mechanical properties such as hardness and reduced modulus of the SiCN films. Surface morphology of …

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Drama Discovery: The Effect Of Dramatic Arts In Combination With Bibliotherapy On The Self-Efficacy Of Students With Emotional And/Or Behavioral Disabilities Regarding Their Understanding Of Their Own Exceptionalities, Michele Jacobs Jan 2005

Drama Discovery: The Effect Of Dramatic Arts In Combination With Bibliotherapy On The Self-Efficacy Of Students With Emotional And/Or Behavioral Disabilities Regarding Their Understanding Of Their Own Exceptionalities, Michele Jacobs

Electronic Theses and Dissertations

The objective of the study was to evaluate the effect of dramatic arts in combination with bibliotherapy, which is the use of literary sources to help people solve complex problems and find understanding about a topic (Sullivan and Strang, 2003). The Drama Discovery curriculum was piloted in a middle school classroom for eleven students with emotional/ behavioral disabilities and one student with delinquent behaviors at a small private alternative education school in Western Pennsylvania. Students with emotional/ behavioral disabilities often have low self-efficacy when it comes to explaining their own disabilities, coping with the label of having a disability, and …

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Rhetorical Implications Of 'Professionalism' For Organizational Culture: Praxis Of Mindfulness, Lynda Brown Jan 2005

Rhetorical Implications Of 'Professionalism' For Organizational Culture: Praxis Of Mindfulness, Lynda Brown

Electronic Theses and Dissertations

This study arose from listening to the historical moment and the multi-disciplinary concerns for higher levels of 'professionalism' and ethics in organizations. This study adds to the conversation with a vision of 'professionalism' as a guiding narrative embodied by dialogic communication ethics for constructively affecting organizational communication. 'Professionalism' is a constructive hermeneutic marked by organizational plurality and diversity offering a more inclusive interpretation and meaning in the twenty-first century. There are rhetorical implications in 'professionalism' when approaching it from social constructivism which views communication as a function that constitutively creates a reality for the organization. Following in the footsteps of …

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Soil Microbial Community Dynamics In Florida Scrub Ecosystem, Maria Albarracin Jan 2005

Soil Microbial Community Dynamics In Florida Scrub Ecosystem, Maria Albarracin

Electronic Theses and Dissertations

Pyrogenic ecosystems are maintained by fires which vary in frequency, seasonality, and intensity. Florida oak-saw palmetto scrub ecosystem is characterized by fires occurring at intervals of 10-20 years. Diverse factors as private land acquisition and development has created a patchy distribution of scrub ecosystems and also interrupted the natural fire cycle. The effects of fire over plant regeneration and fauna habitat utilization of the scrub have been well characterized in previous research. In the present paper the objective is to characterize the short- and long-term fire effects on the soil microbial community. Fire effects were studied in a chronosequence, comprising …

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Effects Of A Shore Protection Project On Loggerhead And Green Turtle Nesting Activity And Reproduction In Brevard County, Florida, Kelly Brock Jan 2005

Effects Of A Shore Protection Project On Loggerhead And Green Turtle Nesting Activity And Reproduction In Brevard County, Florida, Kelly Brock

Electronic Theses and Dissertations

Marine turtle reproductive success is strongly correlated with the stability and quality of the nesting environment. Because females show fidelity to key nesting beaches, the management and physical characteristics of these beaches directly affect future generations of marine turtles and may be essential for the recovery of these threatened and endangered species. The impacts of beach restoration on loggerhead turtles (Caretta caretta) and on green turtles (Chelonia mydas) were investigated. Previous studies concerning beach nourishment projects have focused on loggerhead turtles. I compared data between nourished and non-nourished areas and between loggerhead and green turtles. I found, at one season …

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Expression Of Gal/Galnac Lectin Of Entamoeba Histolytica In Transgenic Chloroplasts To Develop A Vaccine For Amebiasis, Seethamahalakshmi Chebolu Jan 2005

Expression Of Gal/Galnac Lectin Of Entamoeba Histolytica In Transgenic Chloroplasts To Develop A Vaccine For Amebiasis, Seethamahalakshmi Chebolu

Electronic Theses and Dissertations

Amebiasis, also defined as invasive intestinal and extra intestinal amebiasis, is caused by Entameoba histolytica, an invasive protozoan parasite. World Health Organization (WHO) has reported that approximately 50 million people are infected each year causing an estimated 40 to 100 thousand deaths annually. Entameoba histolytica ranks only second to malaria as a protozoan cause of death. Amebiasis occurs world wide but people living in Central and South America, Africa and Asia are the majority to suffer from morbidity and mortality. The enteric parasite has no zoonotic reservoirs and insect vectors for its transmission and infects humans and non-human primates. Therefore, …

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Juvenile Green Turtle (Chelonia Mydas) Foraging Ecology:Feeding Selectivity And Forage Nutrient Analysis, Eliza Gilbert Jan 2005

Juvenile Green Turtle (Chelonia Mydas) Foraging Ecology:Feeding Selectivity And Forage Nutrient Analysis, Eliza Gilbert

Electronic Theses and Dissertations

For the endangered green turtle, Chelonia mydas, a fundamental component of recovery and conservation is an understanding of its foraging ecology. Foraging optimality models suggest animals will select resources of high quality over those of low quality. For green turtles, this behavior is important, as sufficient quantities of nutritionally adequate forage items are necessary for growth and reproduction. One intrinsic element in the understanding of green turtle foraging ecology is to identify and document the availability and quality of forage resources preferred by green turtles. The objectives of this study were: 1) determine whether juvenile green turtles showed a feeding …

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Implementing Lexical And Creative Intentionality In Synthetic Personality, Erik Vick Jan 2005

Implementing Lexical And Creative Intentionality In Synthetic Personality, Erik Vick

Electronic Theses and Dissertations

Creating engaging, interactive, and immersive synthetic characters is a difficult task and evaluating the success of a synthetic character is often even more difficult. The later problem is solved by extending Turing's Imitation Game thusly: computational construct should be evaluated based on the criteria of how well the character can mimic a human. In order to accomplish a successful evaluation of the proposed metric, synthetic characters must be consistently believable and capable of role-appropriate emotional expression. The author believes traditional synthetic characters must be improved to meet this goal. For a synthetic character to be believable, human users must be …

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Predictive Control For Dynamic Systems To Track Unknown Input In The Presence Of Time Delay, Yulan Li Jan 2005

Predictive Control For Dynamic Systems To Track Unknown Input In The Presence Of Time Delay, Yulan Li

Electronic Theses and Dissertations

This study investigated a tracking system to trace unknown signal in the presence oftime delay. A predictive control method is proposed in order to compensate the time delay. Root locus method is applied when designing the controller, parameter setting is carried out through error and trail technique in w-plane. State space equation is derived for the system, with special state chose of tracking error. To analyze the asymptotic stability of the proposed predictive control system, the Lyapunov function is constructed. It is shown that the designed system is asymptotically stable when input signal is rather low frequency signal. In order …

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An Investigation Of The Autoignition Of Power Generation Gas Turbine Fuel Blends Using A Design Of Experiments Approach, Jaap De Vries Jan 2005

An Investigation Of The Autoignition Of Power Generation Gas Turbine Fuel Blends Using A Design Of Experiments Approach, Jaap De Vries

Electronic Theses and Dissertations

Natural gas has grown in popularity as a fuel for power generation gas turbines. However, changes in fuel composition are a topic of concern since fuel variability can have a great impact on the reliability and performance of the burner design. In particular, autoignition of the premixed fuel and air prior to entering the main burner is a potential concern when using exotic fuel blends. To obtain much-needed data in this area, autoignition experiments for a wide range of likely fuel blends containing CH4 mixed with combinations of C2H6, C3H8, C4H10, C5H12, and H2 were performed in a high-pressure shock …

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Monte Carlo Simulation Of Hole Transport And Terahertz Amplification In Multilayer Delta Doped Semiconductor Structures, Maxim Dolguikh Jan 2005

Monte Carlo Simulation Of Hole Transport And Terahertz Amplification In Multilayer Delta Doped Semiconductor Structures, Maxim Dolguikh

Electronic Theses and Dissertations

Monte Carlo method for the simulation of hole dynamics in degenerate valence subbands of cubic semiconductors is developed. All possible intra- and inter-subband scattering rates are theoretically calculated for Ge, Si, and GaAs. A far-infrared laser concept based on intersubband transitions of holes in p-type periodically delta-doped semiconductor films is studied using numerical Monte-Carlo simulation of hot hole dynamics. The considered device consists of monocrystalline pure Ge layers periodically interleaved with delta-doped layers and operates with vertical or in-plane hole transport in the presence of a perpendicular in-plane magnetic field. Inversion population on intersubband transitions arises due to light hole …

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Analysis And Simulation Tools For Solar Array Power Systems, Nattorn Pongratananukul Jan 2005

Analysis And Simulation Tools For Solar Array Power Systems, Nattorn Pongratananukul

Electronic Theses and Dissertations

This dissertation presents simulation tools developed specifically for the design of solar array power systems. Contributions are made in several aspects of the system design phases, including solar source modeling, system simulation, and controller verification. A tool to automate the study of solar array configurations using general purpose circuit simulators has been developed based on the modeling of individual solar cells. Hierarchical structure of solar cell elements, including semiconductor properties, allows simulation of electrical properties as well as the evaluation of the impact of environmental conditions. A second developed tool provides a co-simulation platform with the capability to verify the …

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The Intellectual History Of Inter-War British Fascists, John Tucci Jan 2005

The Intellectual History Of Inter-War British Fascists, John Tucci

Electronic Theses and Dissertations

Between World Wars I and II, allied forces girded themselves to quash yet another enemy bent on world conquest: fascism. In England, however, the British fascists set about to save what they saw as a dying empire. In an effort to restore Britain's greatness, British fascism held to fascist principles and doctrine to stem the flow of immigration, which fascists saw as darkening the pure British culture. While many of the British fascists strongly admired Nazi Germany's version of fascism, they were unique in that they forged their solutions from social ills that were distinctly British. British fascists were unabashedly …

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International Space Station Remote Sensing Pointing Analysis, Craig Jacobson Jan 2005

International Space Station Remote Sensing Pointing Analysis, Craig Jacobson

Electronic Theses and Dissertations

This paper analyzes the geometric and disturbance aspects of utilizing the International Space Station for remote sensing of earth targets. The proposed instrument is SHORE (Station High-Sensitivity Ocean Research Experiment), a multi-band optical spectrometer with 15 m pixel resolution. The analysis investigates the contribution of the error effects to the quality of data collected by the instrument. The analysis begins with the discussion of the coordinate systems involved and then conversion from the target coordinate system to the instrument coordinate system. Next the geometry of remote observations from the Space Station is investigated including the effects of the instrument location …

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The Great Divide: Citizenship And Statelessness, Kristy Belton Jan 2005

The Great Divide: Citizenship And Statelessness, Kristy Belton

Electronic Theses and Dissertations

This thesis investigates the implications of State control of citizenship upon the individual's ability to choose membership in a given State polity. It briefly examines how States gained absolute control over the granting, denying and revoking of citizenship and demonstrates how the acquisition of citizenship and statelessness are both State-determined statuses. The repercussions of statelessness at the individual, regional and global levels are presented to demonstrate the severity of being unable to choose a citizenship. Efforts made by States and the international community to prevent and reduce statelessness are examined in order to illustrate the lack of prioritization given to …

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Assessing Male Body Image: Development And Validation Of The Appearance Inventory For Men (Aim), Daniel Agliata Jan 2005

Assessing Male Body Image: Development And Validation Of The Appearance Inventory For Men (Aim), Daniel Agliata

Electronic Theses and Dissertations

Despite evidence suggesting that appearance dissatisfaction among men is on the rise, a void in appropriate forms of body image assessment for males remains. The current study reviews the literature on male body image, identifying the shortcomings and limitations of prior research, and introduces a psychometrically sound, male-specific body image assessment. An initial item-generation study was used to poll 253 males to inquire about their concerns, emotions, behaviors, and related body image topics to be sorted and synthesized into items for scale inclusion. The newly developed Appearance Inventory for Men (AIM) was then administered to 330 males and submitted to …

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