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Evaluation Of Cfd Based Hemolysis Prediction Methods, Oyuna Myagmar Aug 2011

Evaluation Of Cfd Based Hemolysis Prediction Methods, Oyuna Myagmar

Theses

Accurate quantitative evaluation of shear stress-related hemolysis (destruction of red blood cells) could be used to improve blood handling devices, including left ventricular assist devices (LVAD). Computational Fluid Dynamics (CFD) predicts the fluid dynamics of complex pump geometry and has been used to track the shear stress history of red blood cells as they travel through these devices. Several models that predict the relationship between hemolysis, shear stress and exposure time have been used to evaluate the hemolysis in the pumps. However, the prediction accuracy has not reached the satisfactory level. The goal of my thesis is to investigate the …

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Evaluation Of Water Transport In Pemfc Gas Diffusion Layers Using Image Analysis, Michael Daino Aug 2011

Evaluation Of Water Transport In Pemfc Gas Diffusion Layers Using Image Analysis, Michael Daino

Theses

Liquid water transport through the gas diffusion layer (GDL) of a proton exchange membrane fuel cell (PEMFC) was investigated through three interrelated studies utilizing the tools of image processing. First, a new framework and model for the digital generation and characterization of the microstructure of GDL materials with localized binder and polytetrafluoroethylene (PTFE) distributions were developed using 3D morphological imaging processing. The new generation technique closely mimics manufacturing processes and produces realistic 3D phase-differentiated digital microstructures in a cost- and time- effective manner. The generated distributions of hydrophobic (PTFE) and hydrophilic (carbon) regions representative of commercial GDL materials provides water …

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Ereview, Print Industry Center Aug 2011

Ereview, Print Industry Center

RIT Digital Archives

No abstract provided.

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Optical-Pulse Generation And Compression Using A Comb-Driven Gain-Switched Laser Diode And Chromatic-Dispersion Compensator, Sumeeta Arora Jul 2011

Optical-Pulse Generation And Compression Using A Comb-Driven Gain-Switched Laser Diode And Chromatic-Dispersion Compensator, Sumeeta Arora

Theses

Gain-switching is a technique to generate short-width optical pulses. Its main advantage is that it does not require any change in the circuitry of the laser diode used or employ an external optical modulator. The modulating signal generator used by previous studies of gain-switching is an RF sine wave source or a comb generator. Previous work on gain-switching using comb generators as input source have selected only a single value of temporal period. For the first time, we study of the dependence of the optical pulsewidth and peak power of gain-switched pulses as a function of the temporal period using …

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The Dao Of Graphic Design— A Study Of Interrelationship Between The Daodejing In Chinese Daoism And Graphic Design, Rong Chen Jul 2011

The Dao Of Graphic Design— A Study Of Interrelationship Between The Daodejing In Chinese Daoism And Graphic Design, Rong Chen

Theses

Dao has been accumulated for centuries and still remains strong and pertinent to the world today. It is a complex and intriguing philosophy that has many branches and colors. This paper is an analysis of the similarities and differences between the principles held in Daoism and Graphic Design. It is also an interpretation from my personal understanding of both. The concepts derived from my research are presented through several examples, which included the following design principles: Unity, Nature and Wu Wei. The purpose of this thesis is to serve as a bridge, which links concepts of graphic design with Daoism. …

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Visual And Textual Appeals In Banner Advertising: A Content Analysis, Louis Perez Jul 2011

Visual And Textual Appeals In Banner Advertising: A Content Analysis, Louis Perez

Theses

This study investigated textual and visual variables of banner advertisements. A number of research questions were addressed by content analyzing banner advertisements from social media and social networking Websites, including YouTube and Facebook. Implications of linking types of banner advertisements to types of social media sites, including differences between visual and textual content of banner advertisements, are addressed. Results indicate that there were notable differences between banner advertisements found on these sites. Ads are more likely to contain greater visual aspects such as animation on social media sites than they are on social networking sites. Further studies should examine how …

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Scale-Up Of Algae Growth System To Cleanse Wastewater And Produce Oils For Biodiesel Production, Eric Lannan Jul 2011

Scale-Up Of Algae Growth System To Cleanse Wastewater And Produce Oils For Biodiesel Production, Eric Lannan

Theses

Biofuels are a currently a very hot topic with significant interest in both ethanol and biodiesel production. These fuels can be used in current internal combustion engines with little or no modification. Biodiesel can be produced from a variety of sources. One of the most promising sources is microalgae. In some species of algae, oil or lipids can account for as much as 70% of their total biomass. Unfortunately, the cost to produce biodiesel from algae is much too high to compete with petroleum-based fuels. To reduce the production cost of algae, wastewater has been discovered to be an excellent …

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Effects Of Group Apology And Reparation After Breach Of Psychological Contract, Anthony Alongi Jul 2011

Effects Of Group Apology And Reparation After Breach Of Psychological Contract, Anthony Alongi

Theses

Psychological contracts are expectations of reciprocal obligations between an employee and an organization which are held by the employee. Research has shown that victims who experience psychological contract breach may seek to retaliate towards the offending organization. Little research has investigated how a breach can be remediated. The present study investigated the effects of a group apology and reparation on victim‟s sense of power and revenge cognition after a breach of psychological contract. Participants were asked to imagine themselves in a vignette in which a student experiences psychological contract breach by their academic department. The outcome of the scenario differed …

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Digital Media In Education: Expanding The Technology Acceptance Model, Heidi Huntington Jul 2011

Digital Media In Education: Expanding The Technology Acceptance Model, Heidi Huntington

Theses

Studies show that use of computer-based information communication technologies (ICTs) can have positive impacts on student motivation and learning. The present study examines the issue of ICT adoption in the classroom by expanding the technology acceptance model (TAM) to identify factors that contribute to teacher acceptance and use of these technologies in the classroom. A survey was conducted of 57 high school teachers from around the United States. Results show that the variables of teacher belief profile and teacher efficacy can determine high school teacher acceptance of these technologies, when added to the TAM. Additionally, the study confirms previous research …

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Invertebrate Effects On Sediment Biogeochemistry And Microphytobenthos Following Estuarine Macroalgal Blooms, Katherine Premo Jul 2011

Invertebrate Effects On Sediment Biogeochemistry And Microphytobenthos Following Estuarine Macroalgal Blooms, Katherine Premo

Theses

Eutrophication has led to the proliferation of devastating macroalgal blooms in shallow coastal estuaries. Processes at the sediment surface in shallow marine environments can ultimately affect nutrient cycling and the progress of eutrophication. Through bioturbation and grazing of microphytobenthos (MPB) infaunal invertebrates significantly alter redox dependent chemical and microbially-mediated transformations of nutrients and their subsequent release to or uptake from the overlying water column. This study used a series of experiments to investigate the effects of invertebrates on sediment biogeochemistry and nutrient cycling at early and late stages of eutrophication. Unique aspects of this study were the inclusions of multiple …

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Characterization Of Silicon Geiger-Mode Avalanche Photodiodes With Novel Device Architecture, Kimberly Kolb Jul 2011

Characterization Of Silicon Geiger-Mode Avalanche Photodiodes With Novel Device Architecture, Kimberly Kolb

Theses

Geiger-mode avalanche photodiode (GM APD) detectors are capable of counting single photons, measuring arrival times with high resolution, and generating zero read noise (when operated with a CMOS digital readout circuit) due to their unique internal gain characteristics. These capabilities make them exceptionally suited to tasks that require precise arrival time measurements or characterization of faint signals (low photon flux). Laser ranging systems use their arrival time measurement capabilities to build three-dimensional images, while adaptive optics applications have recently begun to capitalize on their low noise and high-speed operation for correcting wavefront imperfections due to atmospheric interference. There is now …

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Athletes Who Tweet: Differences In Audience Perceived Credibility Between Journalists And Athlete's Twitter Accounts, Christine Foster Jul 2011

Athletes Who Tweet: Differences In Audience Perceived Credibility Between Journalists And Athlete's Twitter Accounts, Christine Foster

Theses

The research reveals the differences in audience perceived credibility between an athlete's tweets and a sports reporter's story. Because audiences are drawn to Twitter accounts of athletes, the reporters' sources have become their competition. The study also investigates the difference between how often audiences choose Twitter over a reporter's story to obtain their sports news. A survey of n RIT students measured how often participants obtain sports news from sports reporters' print or online stories and athlete's personal Twitter accounts. The audience's perceived credibility of the sources was also measured. Findings suggest audiences choose online articles as their source for …

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Dimensionality Reduction And Sparse Representations In Computer Vision, Grigorios Tsagkatakis Jul 2011

Dimensionality Reduction And Sparse Representations In Computer Vision, Grigorios Tsagkatakis

Theses

The proliferation of camera equipped devices, such as netbooks, smartphones and game stations, has led to a significant increase in the production of visual content. This visual information could be used for understanding the environment and offering a natural interface between the users and their surroundings. However, the massive amounts of data and the high computational cost associated with them, encumbers the transfer of sophisticated vision algorithms to real life systems, especially ones that exhibit resource limitations such as restrictions in available memory, processing power and bandwidth. One approach for tackling these issues is to generate compact and descriptive representations …

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Analysis Of The Use Of Ratios For Process Management And Decision-Making, Donald Holmes, A. Erhan Mergen Jul 2011

Analysis Of The Use Of Ratios For Process Management And Decision-Making, Donald Holmes, A. Erhan Mergen

Articles

Ratios are commonly used in business for various applications, such as quality control, finance, sales, etc. The objective of this paper is to call attention to the possibility of the misuse of ratios used in monitoring processes and offer ways to avoid such misuse.

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A Statistical Data Mining Approach To Determining The Factors That Distinguish Championship Caliber Teams In The National Football League, Ernest Fokoué, Dan Foehrenbach Jul 2011

A Statistical Data Mining Approach To Determining The Factors That Distinguish Championship Caliber Teams In The National Football League, Ernest Fokoué, Dan Foehrenbach

Articles

This paper uses machine learning and data mining techniques to explore most of the performance measurements used in American football. The main goal is to determine/extract those factors that are most responsible for the success of the so-called great NFL teams. We consider a very large number of commonly used performance statistics and variables along with success indicators like winning percentage, playoff appearance, and championship wins. It is held by many football analysts/experts that defense wins championships. In this paper, we seek to establish if indeed there is ample evidence that the so called dominant teams are based on more …

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A Collaborative Study Of Vitamin D3 Uptake By Microcrustaceans (Daphnia Spp.): Studies Towards Linking Vitamin D3 And Nile Blue A, Pamela Meehl Jul 2011

A Collaborative Study Of Vitamin D3 Uptake By Microcrustaceans (Daphnia Spp.): Studies Towards Linking Vitamin D3 And Nile Blue A, Pamela Meehl

Theses

A collaborative study to determine what role, if any, vitamin D3 plays in the survival of a zooplankton genus, Daphnia (spp.), under the stress of UV radiation is currently ongoing. The portion of the study described here is a method towards linking vitamin D3 to a fluorophore (Nile Blue A). Functionalization and linking of Nile Blue A and vitamin D3 is explored utilizing "click" chemistry, carbonyldiimidazole (CDI) coupling and diisopropylcarbodiimide (DIC) coupling.

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Project Tips: A Review Of Rochester's Law Enforcement-Community Collaborative, Gregory Drake Jul 2011

Project Tips: A Review Of Rochester's Law Enforcement-Community Collaborative, Gregory Drake

Theses

This analysis examines a community-police collaborative named Project TIPS that started in Rochester, NY in 2008. As an active member of the collaborative, the researcher uses systematic observation and structured interviews with collaborative leaders stretching three years of program implementation. Theories of community functions and community policing are examined to analyze the effectiveness of Project TIPS at enhancing community functioning and public safety.

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Feedback Regulated Star Formation In Cool Core Clusters Of Galaxies, Grant Tremblay Jul 2011

Feedback Regulated Star Formation In Cool Core Clusters Of Galaxies, Grant Tremblay

Theses

The classical "cooling flow" model historically associated with "cool core" clusters of galaxies fails in the absence of an external, non-gravitational heating mechanism needed to offset catastrophic radiative losses of the X-ray bright intracluster medium (ICM). Numerous proposed solutions exist, including feedback from active galactic nuclei (AGN), which may elegantly calibrate fundamental relationships such as the coupled co-evolution of black holes and the stellar component of their host galaxies. AGN feedback cannot completely offset cooling at all times, however, as the brightest cluster galaxies (BCGs) in cool core clusters harbor extensive warm (∼104 K) and cold (10 < T < 104 K) gas reservoirs whose physical properties are regulated by ongoing star formation and an unknown, non-stellar heating mechanism. We present a doctoral thesis broadly related to these issues, particularly as they pertain to cooling flows, the triggering of AGN activity, and the associated energetic feedback that may play a critical role in heating the ambient environment on tens to hundreds of kiloparsec scales. We begin with a summary of the relevant background material, and in Chapter 2 we present a multiwavelength study of effervescent AGN heating in the cool core cluster Abell 2597. Previously unpublished Chandra X-ray data show the central regions of the hot intracluster medium (ICM) to be highly anisotropic on the scale of the BCG, permeated by a network of kpc-scale X-ray cavities, the largest of which is cospatial in projection with extended 330 MHz radio emission. We present spectral maps of projected, modeled gas properties fit to the X-ray data. The X-ray temperature map reveals two discrete, ``hard-edged'' structures, including a ∼15 kpc ``cold filament'' and an arc of hot gas which in projection borders the inner edge of the large X-ray cavity. We interpret the latter in the context of the effervescent AGN heating model, in which cavity enthalpy is thermalized as the ambient keV gas rushes to refill the wake of the buoyant bubble. The hot arc revealed in the temperature map may be one of the first instances in which ICM/ISM heating by AGN feedback is directly observed. The ∼15 kpc soft excess filament, part of which is cospatial with extended 1.3 GHz radio emission, may be associated with dredge-up of low entropy gas by the propagating radio source. Results from our study of the hot X-ray gas are framed in the context of inferred young stellar component ages associated with the central emission line nebula in the BCG. We find that inferred ages of the young stellar component are both younger and older than the inferred ages of the X-ray cavities, suggesting that low levels of star formation have managed to persist amid the AGN feedback-driven excavation of the X-ray cavity network. In Chapter 3 we present Hubble Space Telescope far-ultraviolet imaging of seven BCGs in cool core clusters selected on the basis of elevated star formation rates. We find that even at low levels, star formation provides a dominant contribution to the ionizing photon reservoir required to power the observed luminosities of the emission line nebula. Weak, compact radio sources are observed in each of these seven BCGs. The combination of higher SFR and lower radio power is consistent with a scenario wherein a low state of AGN feedback allows for increased residual condensation from the ambient X-ray atmosphere, accounting for the elevated star formation rates. In Chapter 4 we present a comparison study of episodic star formation and AGN activity in the giant radio galaxy 3C 236, which is not associated with a cluster. We find that an episodic AGN/starburst connection can be fostered by a non-steady transport of gas to the nucleus. These results are then compared with Abell 2597, enabling a better understanding of the roles that may be played by cooling flows vs. mergers and hot vs. cold accretion modes in depositing the gaseous reservoirs that fuel both star formation and AGN activity. In Chapter 5 we broaden the context of the thesis with a search for high redshift Fanaroff-Riley class I radio galaxies, which may act as observable "beacons" for assembling protoclusters. Probing the epoch of cluster assembly will be critical to a better understanding of the evolution of the cool core phenomenon and the history of cluster entropy regulation in general. The relative inability of X-ray cluster selection techniques to extend to these redshifts necessitates alternative detection methods, one of which we describe in this thesis. Finally, in Chapter 6 we discuss the main conclusions of this thesis, which can be summarized as follows: (1) AGN feedback is real, and likely plays a dominant role in regulating the pathway of entropy loss from hot ambient medium to cold gas to star formation; (2) AGN feedback does not establish an impassable "entropy floor" below which gas cannot cool; and (3) star formation plays an important role in determining the temperature and ionization of the warm (∼104 K) and cold (10 < T < 104 K) gas phases in brightest cluster galaxies.

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Blends Of Uv-Cross-Linkable Model Compound And Polyimide; Effect Of Uv Exposure On Viscosity And Mechanical Properties, Indraneel Zope Jul 2011

Blends Of Uv-Cross-Linkable Model Compound And Polyimide; Effect Of Uv Exposure On Viscosity And Mechanical Properties, Indraneel Zope

Theses

The ultimate goal of this project is to synthesize a novel UV-cross-linkable non-linear optical (NLO) pendant polyimide. The following work is dedicated to the synthesis and exposure optimization of the UV cross-linkable component. Knowing that highly stable NLO properties can be achieved through cross-linked polymer matrices, where polymer chain immobilization leads to unidirectional orientation of NLO-phores in poled polymer resulting in maximized operational lifetime and the complete cross-linking cannot be achieved even after a long irradiation time for a photo-cross-linkable polymer, a chalcone-based UV curable Model Compound was synthesized and exposed to UV light. Optimization was carried out with respect …

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Flapping Wing Design For A Dragonfly-Like Micro Air Vehicle, Daniel Prosser Jul 2011

Flapping Wing Design For A Dragonfly-Like Micro Air Vehicle, Daniel Prosser

Theses

In this thesis, the aerodynamics of the Quad-Wing Vehicle, a Micro Air Vehicle designed to hover with four flapping wings in a dragonfly-like configuration, is investigated using Computational Fluid Dynamics (CFD), potential flows analysis, and experimental testing. The CFD analysis investigates the kinematics-parameters design space and identifies values of kinematics parameters that maximize the vertical force production in hovering mode while minimizing the aerodynamic power requirement. It also investigates other important considerations, such as the effect of scaling, multi-wing interactions, and comparison with other flapping configurations. In the potential flows analysis, an unsteady 2D panel code is developed and compared …

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Switching-Based State-Of-Charge Estimation Of Lithium-Ion Batteries, Yingchen Su Jul 2011

Switching-Based State-Of-Charge Estimation Of Lithium-Ion Batteries, Yingchen Su

Theses

The objective of this thesis is to explore a switching-based approach to estimate the state of charge (SOC) of Li-ion batteries. The knowledge of SOC can be utilized to significantly enhance battery performance and longevity. The thesis first presents a brief discussion on various SOC estimation methods, such as coulomb counting, use of electrochemical model combined with Kalman Filtering and open-circuit voltage (OCV). Subsequently, emphasis is placed on the OCV-based method. The advantage of the OCV method lies in its simplicity. It obviates the need for modeling and lowers computational burden compared to model-based approaches. The method yields accurate SOC …

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Investigating Low-Bitrate, Low-Complexity H.264 Region Of Interest Techniques In Error-Prone Environments, Timothy Sperr Jul 2011

Investigating Low-Bitrate, Low-Complexity H.264 Region Of Interest Techniques In Error-Prone Environments, Timothy Sperr

Theses

The H.264/AVC video coding standard leverages advanced compression methods to provide a significant increase in performance over previous CODECs in terms of picture quality, bitrate, and flexibility. The specification itself provides several profiles and levels that allow customization through the use of various advanced features. In addition to these features, several new video coding techniques have been developed since the standard's inception. One such technique known as Region of Interest (RoI) coding has been in existence since before H.264's formalization, and several means of implementing RoI coding in H.264 have been proposed. Region of Interest coding operates under the assumption …

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A Thermally Actuated Microelectromechanical (Mems) Device For Measuring Viscosity, Ivan Puchades Jul 2011

A Thermally Actuated Microelectromechanical (Mems) Device For Measuring Viscosity, Ivan Puchades

Theses

A thermally actuated non-cantilever-beam micro-electro-mechanical viscosity sensor is presented. The proposed device is based on thermally induced vibrations of a silicon-based membrane and its damping due to the surrounding fluid. This vibration viscometer device utilizes thermal actuation through an in-situ resistive heater and piezoresistive sensing, both of which utilize CMOS compatible materials leading to an inexpensive and reliable system. Due to the nature of the actuation, thermal analysis was performed utilizing PN diodes embedded in the silicon membrane to monitor its temperature. This analysis determined the minimum heater voltage pulse amplitude and time in order to prevent heat loss to …

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Ereview, Print Industry Center Jul 2011

Ereview, Print Industry Center

RIT Digital Archives

No abstract provided.

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The Quaestor Quarterly Summer 2011, Institute Audit, Compliance & Advisement Jul 2011

The Quaestor Quarterly Summer 2011, Institute Audit, Compliance & Advisement

RIT Digital Archives

No abstract provided.

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Decide Vaccine Prices And Subsidies For Developing Countries, Wenbo Zhang Jun 2011

Decide Vaccine Prices And Subsidies For Developing Countries, Wenbo Zhang

Theses

Vaccination has been deemed the most cost-effective way to fight against preventable diseases and improve global health. In recent years, expensive combination vaccines which provide multiple antigens in a single shot have been developed to replace traditional monovalent vaccines and have become the preferred choice of healthcare systems in industrialized countries. High prices have not only barricaded low-income countries from accessing combination vaccines but also lure vaccine manufacturers to shift their production capacity from making traditional vaccines to combination vaccines. Such a shift could eventually lead to shortages on the vaccine supply for low-income countries. This work extends the ABP …

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A Hemodynamic Investigation Of A Complete Arteriovenous Model Of The Arm, Arteriovenous Fistula, And Distal Revascularization And Interval Ligation, Nicole Varble Jun 2011

A Hemodynamic Investigation Of A Complete Arteriovenous Model Of The Arm, Arteriovenous Fistula, And Distal Revascularization And Interval Ligation, Nicole Varble

Theses

One of the largest problems facing vascular surgeons today is malfunctioning arteriovenous fistulas (AVF) in patients on hemodialysis. A radial- cephalic AVF is a vessel in the arm that directs blood flow from the high pressure arteries to the low pressure veins and is put in place so blood can be withdrawn from a patient at a point where high volume blood flow occurs. After a period of maturation, the fistula often expands to adapt for the increase flow and can therefore be accessed repeatedly for hemodialysis. However, in a small percentage of cases, access related steal can lead to …

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Exemplar Versus Base Rate Information Messages: Effect On African-Americans’ Intentions Toward Signing A Donor Card, Aisha O’Mally Jun 2011

Exemplar Versus Base Rate Information Messages: Effect On African-Americans’ Intentions Toward Signing A Donor Card, Aisha O’Mally

Theses

This study examines factors that may play a role in moderating the influence of a message on African-Americans to become organ donors. The message and sender were both manipulated to examine the impact of exemplars versus base rates within the message as well as the race of the sender. An anthropomorphic agent was used to present information about organ donation. Respondents completed a pre-test survey, viewed a short video, and then completed a post-test. There was no significant evidence found that either base rate or exemplar information influenced African-Americans to become organ donors. The expectation that participants would identify more …

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The Hyper-Log-Chromaticity Space For Illuminant Invariance, Samuel Brisebois Jun 2011

The Hyper-Log-Chromaticity Space For Illuminant Invariance, Samuel Brisebois

Theses

Variation in illumination conditions through a scene is a common issue for classification, segmentation and recognition applications. Traffic monitoring and driver assistance systems have difficulty with the changing illumination conditions at night, throughout the day, with multiple sources (especially at night) and in the presence of shadows. The majority of existing algorithms for color constancy or shadow detection rely on multiple frames for comparison or to build a background model. The proposed approach uses a novel color space inspired by the Log-Chromaticity space and modifies the bilateral filter to equalize illumination across objects using a single frame. Neighboring pixels of …

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Polar Dependence, Aspasia Tsoutsoura Jun 2011

Polar Dependence, Aspasia Tsoutsoura

Theses

This thesis is an exploration of the relation between contrasting pairs and materials. For my thesis body of work I chose metal and soft materials to be my opposites. Through sculptures and prints I explore the feelings and thoughts their juxtaposition causes, bringing out both their strong and weak characteristics and showing their interdependence. Polar Dependence is what characterizes these two "opposites", showing the need for these differences in our personal life and relationships. It asks the viewer to think beyond the ordinary use of these materials, to contemplate their qualities, the relationship between soft and strong, cold and warm, …

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