This manuscript includes an investigation of decision making in alternative modes of transportation in order to understand consumers' decision in different contexts. In essay 1 of this study, the motives for participation in situated ridesharing is investigated. The study proposes a theoretical model that includes economic benefits, time benefits, transportation anxiety, trust, and reciprocity either as direct antecedents of ridesharing participation intention, or mediated through attitude towards ridesharing. Essay 2 of this study, focuses on self-driving vehicles as one of the recent innovations in transportation industry. Using a survey approach, the study develops a conceptual model of consumers' anticipated motives. Both essays use partial least square- structural equation modeling for assessing the proposed theoretical models.

A collection of poems that explores notions of disability, family, and belief, with a preface that meditates on questions related to the ethical ramifications of various approaches to the making of poetry and art that takes up the suffering of others as subject matter.

With the advent of information explosion age, larger capacity disk drives are used to store data and powerful devices are used to process big data. As the scale and complexity of computer systems increase, we expect these systems to provide dependable and energy-efficient services and computation. Although hard drives are reliable in general, they are the most commonly replaced hardware components. Disk failures cause data corruption and even data loss, which can significantly affect system performance and financial losses. In this dissertation research, I analyze different manifestations of disk failures in production data centers and explore data mining techniques combined with statistical analysis methods to discover categories of disk failures and their distinctive properties. I use similarity measures to quantify the degradation process of each failure type and derive the degradation signature. The derived degradation signatures are further leveraged to forecast when future disk failures may happen. Meanwhile, this dissertation also studies energy efficiency of high performance computers. Specifically, I characterize the power and energy consumption of Haswell processors which are used in multiple supercomputers, and analyze the power and energy consumption of Legion, a data-centric programming model and runtime system, and Legion applications. We find that power and energy …

Negation is a complex phenomenon present in all human languages, allowing for the uniquely human capacities of denial, contradiction, misrepresentation, lying, and irony. It is in the first place a phenomenon of semantical opposition. Sentences containing negation are generally (a) less informative than affirmative ones, (b) morphosyntactically more marked—all languages have negative markers while only a few have affirmative markers, and (c) psychologically more complex and harder to process. Negation often conveys positive meaning. This meaning ranges from implicatures to entailments. In this dissertation, I develop a system to reveal the underlying positive interpretation of negation. I first identify which words are intended to be negated (i.e, the focus of negation) and second, I rewrite those tokens to generate an actual positive interpretation. I identify the focus of negation by scoring probable foci along a continuous scale. One of the obstacles to exploring foci scoring is that no public datasets exist for this task. Thus, to study this problem I create new corpora. The corpora contain verbal, nominal and adjectival negations and their potential positive interpretations along with their scores ranging from 1 to 5. Then, I use supervised learning models for scoring the focus of negation. In order to …

Brazos is a collection of poetry that comments on and critiques life in a small town in Texas. These poems situate the speaker both in this town and in spaces removed from the town, but the work always grapples with questions of how the speaker identifies himself via the relationship to that space. The creative portion is accompanied by a critical introduction that looks at the intersections of poetry and the lyric essay.

This work involves synthesis and characterization of isotropic and anisotropic noble metal nanoparticles for applications ranging from antimicrobial uses to anticancer applications. These nanomaterials are stabilized in genuinely benign biomaterials ranging from polymers to cross linked proteins for targeted cancer treatments. The nanoparticles are found to have tunable optical properties.

Corrosion is one of the most expensive failures in industries that used metal components and other construction materials. In fact, corrosion is responsible for hundreds of billions-dollar loss in the US alone each year. In general, corrosion occurs when metal surfaces are exposed to water, oxygen, acids, bases, or salts. Therefore, metal substrates must be protected by using materials that act as barriers to avoid destructive corrosion attack. Aluminum is one of the most common metals used in the industry; and it is used in many places such as refining and petroleum production equipment, pipelines, and fossil fuel power plants. Aluminum is known to have corrosion resistance due to the forming of an oxide layer that can be reformed rapidly if the surface gets damaged. However, in the long-term the oxide layer cannot protect the aluminum surface from corrosion because it is stable only in neutral mediums and it is soluble in acidic and basic environments. Barrier protection is one of the most effective methods that prevent aluminum surfaces from being exposed to corrosive environments. These barriers can be organic or inorganic coatings that can limit the electron transport or the cathodic and the anodic reactions between aluminum alloys and …

The purpose of the study was two-fold. First, the study explored how self-identified Afrocentrist professors in higher education utilized Afrocentric pedagogy and andragogy to address the learning needs of students, specifically Black women students. Second, the study explored the ways in which Black women students experienced that learning in the higher education classroom. The purpose was advanced through an in-depth analysis of Afrocentric teaching and learning in the higher education. A sample of five self-identified Afrocentric faculty members - three females and two males - and five Black women students who studied with those professors was identified. Participants were interviewed individually in-person and by telephone. Data analysis resulted in the themes of the importance of living an Afrocentric life in which the African body is centered and elevated, rejection of European dominance and universalism, re-routing history, and introducing Afrocentricity as a methodology from which to analyze human life. These themes presented core values, approaches, practices and characteristics utilized in Afrocentric teaching. Findings also showed that the Black women student participants received multiple benefits from receiving an Afrocentric education that assisted them in their journeys through higher education. Study findings provided a foundation for the guidebook "Teach Me, Toward Me Kuongoza, …

There is currently an increasing trend among the American working population to voluntarily join the gig economy. New terms like the gig economy, sharing economy, internet freelancing, and eLancing have been created to understand this emerging trend among today's workforce. There is a small, yet highly relevant, body of scholarly literature in human resource management that is focused specifically on the eLancing economy as a subset of the gig economy. The purpose of this research is to acknowledge and contribute to this timely literature, which has adequately recognized the enormous potential of this new trend of working. Grounded in the psychology of working theory, a theoretical typology of eLancers is proposed based on the workers' level of volition to be able to choose eLancing as their employment. Further, various predictors such as demographics and personality characteristics were explored on the basis of which eLancers can be classified into types. The study also proposes that different types of eLancers differ in their attitudinal and behavioral work and life outcomes. Prior research has shown that career decisions made by individuals with high work volition relate to higher levels of overall well-being. Hence, classifying eLancers on the basis of their varying levels of …

The rising rate of the autism spectrum disorders (ASD) has resulted in challenges for teachers in public schools, concerning the delivery of evidence-based practices for superior outcomes. Thus, school districts are in need of professional learning options that can be efficiently and effectively delivered to improve the procedural fidelity of interventions. The purpose of this study is to demonstrate the effectiveness of using telepractice to teach autism teachers how to contrive motivating operations to teach manding to students with ASD. By utilizing multiple baselines across participants design, four autism teachers in public schools received intervention support through an online module along with video models as well as direct performance feedback from autism specialists via video-conferencing. The primary dependent variable was the percentage of correct responses from the instructional procedures of task analysis, and the secondary measure was the subsequent rate of student mands. Data were analyzed both visually (i.e., through the study of behavioral patterns) and statistically (i.e., analysis of effect size). Results indicate that telepractice increased accuracy of both teacher and student target responses.

Repetitive verbal patterns of speech are a trait associated with high-functioning autism (HFA). For some, this higher-order restricted, repetitive behavior impedes learning, social opportunities, and access to work environments. Despite emerging motivation for establishing social relationships, some individuals with HFA lack the behavioral prerequisites to establish meaningful relationships. The purpose of this study is to demonstrate the effectiveness of teaching interaction to decrease higher-order verbal restricted and repetitive behaviors (RRBs) for four adults with HFA. Through a multiple baseline design across participants, individuals were exposed to a function-based intervention (i.e., teaching interaction) that systematically taught and reinforced alternative communicative behaviors while interrupting repetitive speech with specific feedback. Teaching interaction effectively reduced RRBs and increased alternative conversation for all four participants. Three of the four participants elected to participate in post-intervention maintenance sessions that occurred in individualized naturalistic settings. Their conversation behaviors maintained with one participant receiving one booster session.

This work investigates the Fresnel-lens-based solar concentrator-receiver system in a multi-perspective manner to design, test and fabricate this concentrator with high-efficiency photon and heat outputs and a minimized effect of chromatic aberrations. First, a MATLAB®-incorporated algorithm optimizes both the flat-spot and the curved lens designs via a statistical ray-tracing methodology of the incident light, considering all of its incidence parameters. The target is to maximize the solar ray intensity on the receiver's aperture, and therefore, achieve the highest possible focal flux. The algorithm outputs prismatic and dimensional geometries of the Fresnel-lens concentrator, which are simulated by COMSOL® Multiphysics to validate the design. For the second part, a novel genetically-themed hierarchical algorithm (GTHA) has been investigated to design Fresnel-lens solar concentrators that match with the distinct energy input and spatial geometry of various thermal applications. Basic heat transfer analysis of each application decides its solar energy requirement. The GTHA incorporated in MATLAB® optimizes the concentrator characteristics to secure this energy demand, balancing a minimized geometry and a maximized efficiency. Two experimental applications were selected from literature to validate the optimization process, a solar welding system for H13 steel plates and a solar Stirling engine with an aluminum-cavity receiver attached to the …

Photophysical properties of an array of various polyaromatic hydrocarbons were benchmarked with B3LYP, M06 and B97D methods coupled with Pople and CEP-31G(d) basis sets. Results from the benchmark show the importance of diffuse basis sets when modeling the electronic properties of highly conjugated systems and provide qualitative reliable accuracy with certain levels of theory. B97D and M06 are applied to modeling pyrene adducts governed by non-covalent interactions in both gaseous and condensed states to reproduce experimental spectra. DFT calculations with both B97D and M06 functionals show qualitatively and quantitatively that pyrene dimer is a stronger π–base as compared to its monomer. Binding energies coupled with MEP, PCA and Qzz results show that the difference in π-basicity of the monomer and dimer impacts the supramolecular chemistry involved in adducts formed with super π-acidic silver cyclometallic trimer (CTC). Non-covalent interactions between coinage metal CTCs and ammonia/phosphine substrates is reported. Interactions between these substrates and the facial plane of the π-rich gold CTC reveal a novel interaction, where the typical Lewis acid/base roles are reversed for the substrates. Adducts formed through this type of interaction define typical Lewis bases like ammonia and phosphine as Lewis acids, wherein the partially positive hydrogens coordinate to …

William Gillock, a 20th-century American composer and pedagogue, composed numerous works in the styles of different periods for early intermediate-level piano students. The purpose of this dissertation is to introduce Gillock's pieces to teachers of early intermediate students and illustrate how they can be used as a bridge to the study of similar music from Baroque, Classical, and Romantic periods. Gillock's Little Suite in Baroque Style is compared with Handel's Suite in E Major, HWV 430; his Accent on Analytical Sonatinas (Classical) is compared with Clementi's Piano Sonatinas, Op. 36, No. 3, 5, 6; and his Lyric Preludes in Romantic Style (Romantic) is compared with Chopin's 24 Preludes, Op. 28, No. 3, 6, 9, 16, 18, and 24. Each work is examined to reveal its compositional and technical elements along with pedagogical concepts.

In 1873, a financial crisis plunged the United States into a deep economic depression that exacerbated a number of post-war economic issues. By the late 1870s, political dissent centered primarily on financial issues merged into the Greenback movement, which represented a loose coalition of reformers calling for economic relief based on the expanded use of greenbacks (paper currency issued by the United States Treasury during the Civil War). The Greenback Party emerged as a direct response to federal financial policies, but in Texas, it also provided a broad political platform for those opposed to the policies of "Redeemer/Bourbon" Democrats. The Greenback Party of Texas brought together a wide range of dissenters, including disgruntled Democrats, ousted Republicans, and many different economic and social reformers. From 1876, when the first Greenback clubs appeared in Texas, to the Greenback Party's virtual disappearance after the election of 1884, the Texas Greenbackers reached across boundaries of section, race, class, and sometimes gender; brought together farmers, workers, and professionals; Southerners and Northerners, white and black; former Confederates and former Unionists; native-born Americans and immigrants; and received sizable support from multiple counties in the northern, eastern, and central part of the state. In spite of its short …

Cognitive Radio (CR) technology creates the opportunity for unlicensed users to make use of the spectral band provided it does not interfere with any licensed user. It is a prominent tool with spectrum sensing functionality to identify idle channels and let the unlicensed users avail them. Thus, the CR technology provides the consumers access to a very large spectrum, quality spectral utilization, and energy efficiency due to spectral load balancing. However, the full potential of the CR technology can be realized only with CRs equipped with accurate mechanisms to predict/sense the spectral holes and vacant spectral bands without any prior knowledge about the characteristics of traffic in a real-time environment. Multi-layered perception (MLP), the popular neural network trained with the back-propagation (BP) learning algorithm, is a keen tool for classification of the spectral bands into "busy" or "idle" states without any a priori knowledge about the user system features. In this dissertation, we proposed the use of an evolutionary algorithm, Bacterial Foraging Optimization Algorithm (BFOA), for the training of the MLP NN. We have compared the performance of the proposed system with the traditional algorithm and with the Hybrid GA-PSO method. With the results of a simulation experiment that this …

This dissertation emphasizes the security aspects of real-time media. The problems of existing real-time media protections are identified in this research, and viable solutions are proposed. First, the security of real-time media depends on the Secure Real-time Transport Protocol (SRTP) mechanism. We identified drawbacks of the existing SRTP Systems, which use symmetric key encryption schemes, which can be exploited by attackers. Elliptic Curve Cryptography (ECC), an asymmetric key cryptography scheme, is proposed to resolve these problems. Second, the ECC encryption scheme is based on elliptic curves. This dissertation explores the weaknesses of a widely used elliptic curve in terms of security and describes a more secure elliptic curve suitable for real-time media protection. Eighteen elliptic curves had been tested in a real-time video transmission system, and fifteen elliptic curves had been tested in a real-time audio transmission system. Based on the performance, X9.62 standard 256-bit prime curve, NIST-recommended 256-bit prime curves, and Brainpool 256-bit prime curves were found to be suitable for real-time audio encryption. Again, X9.62 standard 256-bit prime and 272-bit binary curves, and NIST-recommended 256-bit prime curves were found to be suitable for real-time video encryption.The weaknesses of NIST-recommended elliptic curves are discussed and a more secure new …

The performance of electrical and optical devices based on two-dimensional semiconductors (2D) such as molybdenum disulfide is critically influenced due to very poor light absorption in the atomically thin layers. In this study, the phonon mediated optical absorption and emission properties in single atomic layers of MoS2 have been investigated. The electronic transitions in MoS2 due to near-field optical interaction and the influence of interface phonons due to the dielectric substrate GaN on the relaxation of optically generated carriers will be described. The near-field interaction can be induced in the presence of metal plasmons deposited on the surface of MoS2 monolayers. A hybrid metal-semiconductor system was realized by the deposition of silver (Ag) NPs on MoS2 layer and the localized plasmon modes were selectively chosen to interact with quasiparticles such as excitons and phonons. These quasiparticles are confined within the single atomic layer of MoS2 and are stable at room temperatures due to high binding energy. The lattice vibrational modes in MoS2 can be optically excited with the pulses from a femtosecond laser. These phonon modes can be optically dressed due to near-field interaction in the hybrid Ag-MoS2 system under an optical excitation resonant to localized plasmon modes. The coherent …

In this dissertation, I apply Gadamerian philosophical hermeneutics to examine interpretations of the food-drug relationship within the contexts of health and medicine. Assumptions regarding the relationship between these categories undergird a substantial academic discourse and function as key components in worldviews beyond the academy. Despite this, little work has been done in foregrounding them to allow for critique and consideration of alternative perspectives. Unearthing philosophical assumptions within various fields, epistemic systems, and regulatory bodies, I classify food-drug interpretations into two main categories: dichotomous interpretations of the categories of "food" and "drugs" as ontologically distinct, and continuum-based interpretations where these categories overlap. Rather than arguing for a single appropriate way of understanding the food-drug relationship, my project aims to disclose the complexities of both sets of interpretations, illustrating their virtues and vices, and underscoring the need for people to call their own interpretations into question while taking seriously those of others. The dialogical structure of philosophical hermeneutics provides a useful foundation for dialogue within and between dichotomous and continuum-based interpretations. We do not have unmediated access to a mind-independent reality, the terms "food" and "drugs" do not necessarily refer to natural kinds, and all interpretations likely have different degrees of strengths …

This dissertation focuses on the computational investigation of gold(I) acyclic diaminocarbene (ADC) complexes and their application in homogeneous gold(I) catalysis. Chapter 2 is an in-depth computational investigation of the σ- and π-bonding interactions that make up the gold-carbene bond. Due to the inherent conformation flexibility of ADC ligands, distortions of the carbene plane can arise that disrupt orbital overlap between the lone pairs on the adjacent nitrogen atoms and the empty p-orbital of the carbene. This study investigated the affect these distortions have on the strength of the σ- and π-bonding interactions. This investigation demonstrated that while these distortions can affect the σ- and π-bonding interactions, the ADC ligand have to become highly distorted before any significant change in energy of either the σ- or π-bonding interactions occurs. Chapter 3 is a collaborative investigation between experimental and computational methods, DFT calculations were employed to support the experimental catalytic results and determine the role that steric effects have in controlling the regioselectivity of a long-standing electronically controlled gold(I)-catalyzed tandem 1,6-enyne cyclization/hydroarylation reaction with indole. This study demonstrated that by sterically hindering nucleophilic attack of indole at the favored position, nucleophilic attack would occur at a secondary position leading to the selective …

This work provides an alternative theory of gendered consumption that explains chronic and situational shifts in consumers' preferences for masculine, feminine, and androgynous choices, beyond the effects of gender identities.

Current unsupervised approaches for keyphrase extraction compute a single importance score for each candidate word by considering the number and quality of its associated words in the graph and they are not flexible enough to incorporate multiple types of information. For instance, nodes in a network may exhibit diverse connectivity patterns which are not captured by the graph-based ranking methods. To address this, we present a new approach to keyphrase extraction that represents the document as a word graph and exploits its structure in order to reveal underlying explanatory factors hidden in the data that may distinguish keyphrases from non-keyphrases. Experimental results show that our model, which uses phrase graph representations in a supervised probabilistic framework, obtains remarkable improvements in performance over previous supervised and unsupervised keyphrase extraction systems.

As a form of tax and expenditure limitations, property tax exemptions result in an utility gap between two groups of population residing in the same community: free-riders who are paying less than they receive and contributors who are paying more than they receive. This utility gap is problematic to municipalities because contributors may exit the city as this gap becomes wider. How do municipalities respond to the increasing amount of property tax exemptions? Using 41 Texas cities data from 2000 to 2016, this dissertation examines how property tax exemptions affect municipalities' fiscal behavior. The analysis indicates that property tax exemptions lead to higher property tax burden, change municipalities' revenue structure, and lead to less capital spending.

Artificial intelligence (AI) is quickly transforming business operations and society, as AI capabilities are incorporated into applications ranging from mobile personal assistants to self-driving cars. The potentially disruptive nature of AI calls for an extensive investigation into all aspects of AI-human interactions at individual, group, organizational and market levels. However, there is paucity of academic information systems (IS) research in this area that goes beyond the development and testing of specific narrow AI capabilities. AI represents an important opportunity for organizational and behavioral IS researchers, but also presents challenges associated with the underlying complexity of AI technologies and the diversity of AI applications. Understanding how existing AI research and business practice relate to traditional areas of IS research is an important step towards creating a comprehensive behavioral and organizational AI research agenda. This dissertation seeks to achieve a dual purpose in a series of three essays. Essay 1 seeks to understand the current state of business AI research and practice in business through a quantitative literature review, relate the findings to traditional IS research areas, and identify potentially fruitful research areas for AI-focused IS research. Essays 2 and 3 seek to address specific research questions related to one of such …