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Multifunctional, Multimaterial Particle Fabrication Via An In-Fiber Fluid Instability, Joshua Kaufman Jan 2014

Multifunctional, Multimaterial Particle Fabrication Via An In-Fiber Fluid Instability, Joshua Kaufman

Electronic Theses and Dissertations

Spherical micro- and nano-particles have found widespread use in many various applications from paint to cosmetics to medicine. Due to the multiplicity of desired particle material(s), structure, size range, and functionality, many approaches exist for generating such particles. Bottom-up methods such as chemical synthesis have a high yield and work with a wide range of materials; however, these processes typically lead to large polydispersity and cannot produce structured particles. Top-down approaches such as microfluidics overcome the polydispersity issue and may produce a few different structures in particles, but at lower rates and only at the micro-scale. A method that can …

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Quantitative Scanning Transmission Electron Microscopy Of Thick Samples And Of Gold And Silver Nanoparticles On Polymeric Surfaces, Aniruddha Dutta Jan 2014

Quantitative Scanning Transmission Electron Microscopy Of Thick Samples And Of Gold And Silver Nanoparticles On Polymeric Surfaces, Aniruddha Dutta

Electronic Theses and Dissertations

Transmission Electron Microscopy (TEM) is a reliable tool for chemical and structural studies of nanostructured systems. The shape, size and volumes of nanoparticles on surfaces play an important role in surface chemistry. As nanostructured surfaces become increasingly important for catalysis, protective coatings, optical properties, detection of specific molecules, and many other applications, different techniques of TEM can be used to characterize the properties of nanoparticles on surfaces to provide a path for predictability and control of these systems. This dissertation aims to provide fundamental understanding of the surface chemistry of Electroless Metallization onto Polymeric Surfaces (EMPS) through characterization with TEM. …

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The Impact Of A Group Counseling Intervention On Lesbian, Gay, Bisexual, Transgender, And Queer Older Adolescents' Levels Of Hope, Coping, And Suicidality, Catherine Lamb Jan 2014

The Impact Of A Group Counseling Intervention On Lesbian, Gay, Bisexual, Transgender, And Queer Older Adolescents' Levels Of Hope, Coping, And Suicidality, Catherine Lamb

Electronic Theses and Dissertations

This investigation examined the impact of an eight-week group counseling intervention on lesbian, gay, bisexual, transgender, and queer (LGBTQ+) older adolescents’ (aged 18-20) levels of hopefulness, coping skills, and suicidality. An experimental, randomized-controlledtrial research design was employed to identify differences between the intervention group and waitlist control group participants’ hopefulness, coping skills, and suicidality scores. In addition, the relationship between the LGBTQ+ participants’ outcome variables (hopefulness, coping skills, and suicidality) scores was examined. Furthermore, the impact of group therapeutic factors experienced by the LGBTQ+ participants in intervention group for the variables of hopefulness, coping skills, and suicidality was examined. Key …

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Synthetic Generators For Simulating Social Networks, Awrad Mohammed Ali Jan 2014

Synthetic Generators For Simulating Social Networks, Awrad Mohammed Ali

Electronic Theses and Dissertations

An application area of increasing importance is creating agent-based simulations to model human societies. One component of developing these simulations is the ability to generate realistic human social networks. Online social networking websites, such as Facebook, Google+, and Twitter, have increased in popularity in the last decade. Despite the increase in online social networking tools and the importance of studying human behavior in these networks, collecting data directly from these networks is not always feasible due to privacy concerns. Previous work in this area has primarily been limited to 1) network generators that aim to duplicate a small subset of …

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Bioarchaeological Assessment Of Diet And Changes In Femoral And Humeral Stable Isotopic Values Among Subadults At Medieval Alytus, Lithuania., Katherine Page Jan 2014

Bioarchaeological Assessment Of Diet And Changes In Femoral And Humeral Stable Isotopic Values Among Subadults At Medieval Alytus, Lithuania., Katherine Page

Electronic Theses and Dissertations

Establishing a chronology of variation in isotopic values can reveal frailty associated with biological and social age, as well as highlight individuals who vary from typical patterns. Although general dietary characteristics and infant feeding practices were previously unknown for subadults excavated from the cemetery at Alytus, Lithuania (14th-18th centuries), previous research concludes that Alytus' subadults experienced high rates of physiological, metabolic, non-specific stress, in addition to specific diseases like tuberculosis. To investigate nuanced relationships between diet and mortality, nitrogen and carbon stable isotopes from the femoral and humeral midshaft diaphyses of 70 subadults (32 weeks gestation to16 years) were analyzed. …

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Bio-Inspired Attitude Control Of Micro Air Vehicles Using Rich Information From Airflow Sensors, He Shen Jan 2014

Bio-Inspired Attitude Control Of Micro Air Vehicles Using Rich Information From Airflow Sensors, He Shen

Electronic Theses and Dissertations

Biological phenomena found in nature can be learned and customized to obtain innovative engineering solutions. In recent years, biologists found that birds and bats use their mechanoreceptors to sense the airflow information and use this information directly to achieve their agile flight performance. Inspired by this phenomenon, an attitude control system for micro air vehicles using rich amount of airflow sensor information is proposed, designed and tested. The dissertation discusses our research findings on this topic. First, we quantified the errors between the calculated and measured lift and moment profiles using a limited number of micro pressure sensors over a …

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Effects Of Weaning Age On Body Composition And Growth Of Ex Situ California Sea Lion (Zalophus Californianus) Pups, Brandon Davis Jan 2014

Effects Of Weaning Age On Body Composition And Growth Of Ex Situ California Sea Lion (Zalophus Californianus) Pups, Brandon Davis

Electronic Theses and Dissertations

Pinnipeds exhibit a wide range of lactation strategies that vary from just a few days to nearly three years in duration. Phocids have a relatively short, intense nursing period culminating with weaning after just a few days or weeks, while dependent otariids generally take several months of consuming a combined milk and solid food diet before being completely independent. The transition to nutritional independence can be particularly challenging for newly weaned pups, which must adjust to behavioral, physiological and nutritional changes as a milk diet is replaced with solid food. An interruption in energy resources during this formative stage could …

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Particle Manipulation Via Optical Forces And Engineering Soft-Matter Systems With Tunable Nonlinearities., Shima Fardad Jan 2014

Particle Manipulation Via Optical Forces And Engineering Soft-Matter Systems With Tunable Nonlinearities., Shima Fardad

Electronic Theses and Dissertations

One of the most intriguing properties of light-matter interaction is the ability of an electromagnetic field to exert mechanical forces on polarizable objects. This phenomenon is a direct consequence of the fact that light carries momentum, which in turn can be transferred to matter. Mediated by scattering, this interaction usually manifests itself as a “pushing force” in the direction of beam propagation. However, it is possible to judiciously engineer these optical forces, either by tailoring particle polarizability, and/or by structuring the incident light field. As a simple example, a tightly focused laser beam demonstrates strong gradient forces, which may attract …

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Frequency Selective Detection Of Infrared Radiation In Uncooled Optical Nano-Antenna Array, Sushrut Modak Jan 2014

Frequency Selective Detection Of Infrared Radiation In Uncooled Optical Nano-Antenna Array, Sushrut Modak

Electronic Theses and Dissertations

Mid-infrared (mid-IR) detection and imaging over atmospheric transparent 3-5 μm and 8-12 μm bands are increasingly becoming important for various space, defense and civilian applications. Various kinds of microbolometers offer uncooled detection of IR radiation. However, broadband absorption of microbolometers makes them less sensitive to spectrally resolved detection of infrared radiation and the fabrication is also very tedious involving multiple complex lithography steps. In this study, we designed an optical nano-antenna array based detector with narrow frequency band of operation. The structure consists of a two-element antenna array comprised of a perforated metallic hole array coupled with an underneath disk …

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Fluorescence Off-On Sensors For F-, K+, Fe3+, And Ca2+ Ions, Binglin Sui Jan 2014

Fluorescence Off-On Sensors For F-, K+, Fe3+, And Ca2+ Ions, Binglin Sui

Electronic Theses and Dissertations

Fluorescence spectroscopy has been considered to be one of the most important research techniques in modern analytical chemistry, biochemistry, and biophysics. At present, fluorescence is a dominant methodology widely used in a great number of research domains, including biotechnology, medical diagnostics, genetic analysis, DNA sequencing, flow cytometry, and forensic analysis, to name just a few. In the past decade, with the rapid development of fluorescence microscopy, there has been a considerable growth in applying fluorescence technique to cellular imaging. The distinguished merits of fluorescence techniques, such as high sensitivity, non-invasiveness, low cytotoxicity, low cost, and convenience, make it a promising …

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Assessment Of Instructional Presentation For Emergency Evacuation Assistive Technology, Michael Boyce Jan 2014

Assessment Of Instructional Presentation For Emergency Evacuation Assistive Technology, Michael Boyce

Electronic Theses and Dissertations

It is often the case that emergency first responders are well equipped and trained to deal with a situation that involves evacuation of someone with a physical disability. However, emergency responders are not always the first line of defense, or they may be otherwise occupied with assisting others. This research examined the effects of instructions for emergency stair travel devices on untrained or novice users. It was hypothesized that through redesign of the evacuation instructions, untrained individuals would be able to successfully prepare an evacuation chair and secure someone with a disability more effectively and efficiently. A prepost study design …

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Human-Robot Interaction For Multi-Robot Systems, Bennie Lewis Jan 2014

Human-Robot Interaction For Multi-Robot Systems, Bennie Lewis

Electronic Theses and Dissertations

Designing an effective human-robot interaction paradigm is particularly important for complex tasks such as multi-robot manipulation that require the human and robot to work together in a tightly coupled fashion. Although increasing the number of robots can expand the area that the robots can cover within a bounded period of time, a poor human-robot interface will ultimately compromise the performance of the team of robots. However, introducing a human operator to the team of robots, does not automatically improve performance due to the difficulty of teleoperating mobile robots with manipulators. The human operator’s concentration is divided not only among multiple …

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Learning Collective Behavior In Multi-Relational Networks, Xi Wang Jan 2014

Learning Collective Behavior In Multi-Relational Networks, Xi Wang

Electronic Theses and Dissertations

With the rapid expansion of the Internet and WWW, the problem of analyzing social media data has received an increasing amount of attention in the past decade. The boom in social media platforms offers many possibilities to study human collective behavior and interactions on an unprecedented scale. In the past, much work has been done on the problem of learning from networked data with homogeneous topologies, where instances are explicitly or implicitly inter-connected by a single type of relationship. In contrast to traditional content-only classification methods, relational learning succeeds in improving classification performance by leveraging the correlation of the labels …

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Nonlinear Integrated Photonics On Silicon And Gallium Arsenide Substrates, Jichi Ma Jan 2014

Nonlinear Integrated Photonics On Silicon And Gallium Arsenide Substrates, Jichi Ma

Electronic Theses and Dissertations

Silicon photonics is nowadays a mature technology and is on the verge of becoming a blossoming industry. Silicon photonics has also been pursued as a platform for integrated nonlinear optics based on Raman and Kerr effects. In recent years, more futuristic directions have been pursued by various groups. For instance, the realm of silicon photonics has been expanded beyond the well-established near-infrared wavelengths and into the mid-infrared (3 - 5 µm). In this wavelength range, the omnipresent hurdle of nonlinear silicon photonics in the telecommunication band, i.e., nonlinear losses due to two-photon absorption, is inherently nonexistent. With the lack of …

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Using Land Cover Mapping And Landscape Metrics To Evaluate Effects Of Urban Development On Ecological Integrity In Florida, Michael Gilbrook Jan 2014

Using Land Cover Mapping And Landscape Metrics To Evaluate Effects Of Urban Development On Ecological Integrity In Florida, Michael Gilbrook

Electronic Theses and Dissertations

The widespread loss and degradation of habitat constitutes the largest threat to biodiversity in North America. While regulatory programs such as the Endangered Species Act of 1973 and wetland permitting under the Clean Water Act have addressed acute assaults on critical habitat, large areas of unprotected uplands have been lost. Urban development, particularly the advent of lower density suburban and rural sprawl, has greatly diminished the extent of contiguous patches of forest habitat and introduced a host of other undesirable effects on ecosystem function. This study sought to evaluate the extent of urban sprawl and its effects on ecological integrity …

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Purification And Characterization Of A Novel Selenocysteine Lyase From Enterococcus Faecalis, Samantha Nelson Jan 2014

Purification And Characterization Of A Novel Selenocysteine Lyase From Enterococcus Faecalis, Samantha Nelson

Electronic Theses and Dissertations

A previous study identified Enterococcus faecalis as one of two bacteria known to have the selD gene and other selenium related genes without having the genes necessary to make selenocysteine or selenouridine. EF2570, a gene in the cluster, was later shown to be upregulated during biofilm formation and also responsible for a selenite- and molybdate-dependent increase in biofilm formation in vitro. The protein encoded was identified as a selenium dependent molybdenum hydroxylase (SDMH), enzymes that contain a labile selenium atom required for activity. While the process of inserting selenocysteine into a protein is well known, the process by which a …

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The Anti-Toxin Properties Of Grape Seed Phenolic Compounds, Patrick Cherubin Jan 2014

The Anti-Toxin Properties Of Grape Seed Phenolic Compounds, Patrick Cherubin

Electronic Theses and Dissertations

Corynebacterium diphtheriae, Pseudomonas aeruginosa, Ricinus communis, Shigella dysentariae, and Vibrio cholerae produce AB toxins which share the same basic structural characteristics: a catalytic A subunit attached to a cell-binding B subunit. All AB toxins have cytosolic targets despite an initial extracellular location. AB toxins use different methods to reach the cytosol and have different effects on the target cell. Broad-spectrum inhibitors against these toxins are therefore hard to develop because they use different surface receptors, entry mechanisms, enzyme activities, and cytosolic targets. We have found that grape seed extract provides resistance to five different AB toxins: diphtheria toxin (DT), P. …

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Synthesis And Study Of Chemo-Hydrothermally Derived Water-Soluble Chitosan And Chiosan-Metal Oxide Composites, Srijita Basumallick Jan 2014

Synthesis And Study Of Chemo-Hydrothermally Derived Water-Soluble Chitosan And Chiosan-Metal Oxide Composites, Srijita Basumallick

Electronic Theses and Dissertations

Chitosan (CS) is a man-made sugar based biopolymer derived from chitin, the second most abundant natural polymer after cellulose. Chitin is sourced from crustacean species such as shrimps and crabs. The chemical structure of chitin contains N-Acetyl D-glucosamine monomer units which forms CS upon deacetylation. In CS, ?-(1-4) linked D-glucosamine units are randomly distributed. Approximately 75% - 80% sugar units contains primary amine groups in commercially available low molecular weight CS. Biodegradability, low toxicity, mucoadhesive and transfecting properties of CS polymer are attractive for applications as oral and nasal drug delivery systems. Chitosan polymer is water insoluble at neutral pH. …

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A Short Window Granger Causality Approach To Identify Brain Functional Pattern Associated With Changes Of Performance Induced By Sleep Deprivation, Muyuan Li Jan 2014

A Short Window Granger Causality Approach To Identify Brain Functional Pattern Associated With Changes Of Performance Induced By Sleep Deprivation, Muyuan Li

Electronic Theses and Dissertations

The comprehensive effect of sleep deprivation on biological and behavioral functions largely remains unknown. There is evidence to support that human sleep must be of sufficient duration and physiological continuity to ensure neurocognitive performance while we are waking. Insufficient sleep would lead to high risk of human-error related to accidents, injuries or even fatal outcomes. However, in modern society, more and more people suffer from sleep deprivation because of the increasing social, academic or occupational demand. It is important to study the effect of sleep deprivation, not only on task performance, but also on neurocognitive functions. Recent research that has …

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Analysis Of Commercial Online Training Videos For Teachers Who Instruct Students With Characteristics Of Autism Spectrum Disorder, Kelly Schaffer Jan 2014

Analysis Of Commercial Online Training Videos For Teachers Who Instruct Students With Characteristics Of Autism Spectrum Disorder, Kelly Schaffer

Electronic Theses and Dissertations

A deficit currently exists in teacher preparation programs for teaching students with Autism Spectrum Disorder (ASD) using evidence-based practices, specifically in the area of Applied Behavior Analysis. As communication deficits are a primary characteristic associated with the diagnosis of ASD teaching communication skills is a common educational goal for students with ASD, and this skill needs to be addressed in teacher education. Mand training is one evidence-based practice applied to teach independent requesting skills to students with ASD. In this study, four teachers serving students with characteristics of ASD in the classroom participated in a multiple-probe across-participants study evaluating the …

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Hispanic Immigrant Parental Messages Of Resiliency And Emotional Regulation To Their Children: An Examination Of Important Variables And An Intervention, Rodrigo Velezmoro Jan 2014

Hispanic Immigrant Parental Messages Of Resiliency And Emotional Regulation To Their Children: An Examination Of Important Variables And An Intervention, Rodrigo Velezmoro

Electronic Theses and Dissertations

This two-part study examined the adjustment of Hispanic immigrants. Part one examined the communication that occurs between Hispanic immigrant parents and their adolescents/young adults about life in the United States (U.S.). It also examined how attitudes toward the U.S. and various protective factors influence psychological adjustment. Hispanic immigrants (n = 123) with an average of 11 years living in the United States and their adolescents/young adults between the ages of 14-22 served as participants. For both parents and their adolescents/young adults, favorable attitudes toward the U.S. were associated with improved psychological adjustment. Contrary to prediction, attitudes toward the U.S. did …

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Functional Data Analysis And Its Application To Cancer Data, Evgeny Martinenko Jan 2014

Functional Data Analysis And Its Application To Cancer Data, Evgeny Martinenko

Electronic Theses and Dissertations

The objective of the current work is to develop novel procedures for the analysis of functional data and apply them for investigation of gender disparity in survival of lung cancer patients. In particular, we use the time-dependent Cox proportional hazards model where the clinical information is incorporated via time-independent covariates, and the current age is modeled using its expansion over wavelet basis functions. We developed computer algorithms and applied them to the data set which is derived from Florida Cancer Data depository data set (all personal information which allows to identify patients was eliminated). We also studied the problem of …

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An Investigation Of The Use Of Disciplinary Texts And Achievement On End-Of-Course Examinations In High School U.S. History Courses, Jocelyn Baldridge Jan 2014

An Investigation Of The Use Of Disciplinary Texts And Achievement On End-Of-Course Examinations In High School U.S. History Courses, Jocelyn Baldridge

Electronic Theses and Dissertations

This study was conducted to examine whether a disparity exists between teacher expectations of honors and non-honors U. S. History students and if students who read more for U. S. History perform better on the U. S. History End-of-Course (EOC) examination. To generate answers to the research questions, both teachers and students in U. S. History courses were surveyed as to how much time was spent reading for U. S. History content both during class and for homework. The student surveys were matched to the U. S. History EOC Developmental Scale Scores to determine if students who responded as reading …

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Dynamical Spin Injection In Graphene, Simranjeet Singh Jan 2014

Dynamical Spin Injection In Graphene, Simranjeet Singh

Electronic Theses and Dissertations

Within the exciting current trend to explore novel low-dimensional systems, the possibility to inject pure spin currents in graphene and other two-dimensional crystals has attracted considerable attention in the past few years. The theoretical prediction of large spin relaxation times and experimentally observed mesoscopic-scale spin diffusion lengths places graphene as a promising base system for future spintronics devices. This is due to the unique characteristics intrinsic to the two-dimensional lattice of carbon atoms forming graphene, such as the lack of nuclear spins and weak spin-orbit coupling of the charge carriers. Interestingly for some spintronic applications, the latter can be chemically …

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Inversion Of The Broken Ray Transform, Roman Krylov Jan 2014

Inversion Of The Broken Ray Transform, Roman Krylov

Electronic Theses and Dissertations

The broken ray transform (BRT) is an integral of a function along a union of two rays with a common vertex. Consider an X-ray beam scanning an object of interest. The ray undergoes attenuation and scatters in all directions inside the object. This phenomena may happen repeatedly until the photons either exit the object or are completely absorbed. In our work we assume the single scattering approximation when the intensity of the rays scattered more than once is negligibly small. Among all paths that the scattered rays travel inside the object we pick the one that is a union of …

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Antimicrobial Peptide Resistance And Immunomodulation By Hiv-1 Gp41, Matthew Wood Jan 2014

Antimicrobial Peptide Resistance And Immunomodulation By Hiv-1 Gp41, Matthew Wood

Electronic Theses and Dissertations

Fusion inhibitors are a class of antiretroviral drugs used to prevent entry of HIV into host cells. Many of the fusion inhibitors being developed, including the drug enfuvirtide (ENF), are peptides designed to mimic, and thereby competitively inhibit, the viral fusion protein gp41. An exception to this is a class of cyclic, cationic, antimicrobial peptides known as θ-defensins, which are produced by many non-human primates and exhibit broad-spectrum antiviral and antibacterial activity. Currently, the θ-defensin analog RC-101 is being developed as a microbicide to prevent sexual transmission of HIV-1. Understanding potential RC-101 resistance, and how resistance to other fusion inhibitors …

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The Contribution Of College Students' Attachment Styles And Social Media Practices On Their Relationship Development, Renee Sherrell Jan 2014

The Contribution Of College Students' Attachment Styles And Social Media Practices On Their Relationship Development, Renee Sherrell

Electronic Theses and Dissertations

The purpose of this research study was to investigate the directional relationship between college students' attachment styles and social media practices with their relationship development. This investigation tested the theoretical model that undergraduate students' (N = 717) attachment styles (as measured by the Experiences in Close Relationships-Short form [ECR-S; Wei et al., 2007]) and social media practices (as measured by the Facebook Intensity Scale [FBI; Ellison et al., 2007] and Motives for Going Facebook Official Scale [MGFBO; Fox & Warber, 2013]) contributed to their quality of relationship development (as measured by the Parks Relational Development Scale [PRDS; Parks & Roberts, …

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Performing On The Screen: An Exploration Of Gender Representation In Technology Video Advertisements, Subriena Persaud Jan 2014

Performing On The Screen: An Exploration Of Gender Representation In Technology Video Advertisements, Subriena Persaud

Electronic Theses and Dissertations

This study investigates the representation of gender in technology-related video advertisements. This thesis quantitatively and qualitatively examined 54 of the most recent commercials by the top nine Fortune 500 technology companies. A total of 407 characters were coded and quantitatively analyzed while the videos themselves were qualitatively assessed with particular attention given to the videos' themes and the interactions between the characters and the technology products and services. Results of the analyses showed that there were more male, Caucasian characters than any other character type based on gender and race/ethnicity. Females were mainly characterized according to traditional stereotypes, such as …

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Practical Issues In Gpram Development, Yin Li Jan 2014

Practical Issues In Gpram Development, Yin Li

Electronic Theses and Dissertations

In this thesis, two parts of practical issues in the GPRAM system design are included. The first part is the coding part. The sum-product decoding algorithm of LDPC codes has been refined to fit for the GPRAM hardware implementation. As we all know, communication channel has noise. The noise in telecom system is different from that in GPRAM systems. So the noise should be handled well in the GPRAM design. A noise look-up table was created for FPGA and those noises in the table are quantized. The second part of the thesis is to convert perfect images in video stream …

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Learning To Grasp Unknown Objects Using Weighted Random Forest Algorithm From Selective Image And Point Cloud Feature, Md Shahriar Iqbal Jan 2014

Learning To Grasp Unknown Objects Using Weighted Random Forest Algorithm From Selective Image And Point Cloud Feature, Md Shahriar Iqbal

Electronic Theses and Dissertations

This method demonstrates an approach to determine the best grasping location on an unknown object using Weighted Random Forest Algorithm. It used RGB-D value of an object as input to find a suitable rectangular grasping region as the output. To accomplish this task, it uses a subspace of most important features from a very high dimensional extensive feature space that contains both image and point cloud features. Usage of most important features in the grasping algorithm has enabled the system to be computationally very fast while preserving maximum information gain. In this approach, the Random Forest operates using optimum parameters …

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