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Integrating environmental data acquisition and low cost Wi-Fi data communication. (open access)

Integrating environmental data acquisition and low cost Wi-Fi data communication.

This thesis describes environmental data collection and transmission from the field to a server using Wi-Fi. Also discussed are components, radio wave propagation, received power calculations, and throughput tests. Measured receive power resulted close to calculated and simulated values. Throughput tests resulted satisfactory. The thesis provides detailed systematic procedures for Wi-Fi radio link setup and techniques to optimize the quality of a radio link.
Date: December 2009
Creator: Gurung, Sanjaya
System: The UNT Digital Library
Interactions of equivalence and other behavioral relations: Simple successive discrimination training. (open access)

Interactions of equivalence and other behavioral relations: Simple successive discrimination training.

The experimenter asked if documented equivalence class membership would influence the development of shared discriminative stimulus function established through simple successive discrimination training. In Experiment 1, equivalence classes were established with two sets of 9 stimuli. Common stimulus functions were then trained within or across the equivalence classes. Greater acquisition rates of the simple discriminations with stimuli drawn from within the equivalence classes were observed. In Experiment 2, a third stimulus set was added with which no equivalence relations were explicitly trained. The findings of Experiment 1 were replicated, but the Set 3 results were inconsistent across subjects. The outcomes of the two experiments demonstrate that equivalence classes have an effect on other behavioral relations which requires further investigation.
Date: December 2009
Creator: Brackney, Ryan
System: The UNT Digital Library
Intertextualization: An historical and contextual study of the battle villancico, El más augusto campeón. (open access)

Intertextualization: An historical and contextual study of the battle villancico, El más augusto campeón.

This document addresses the cultural and significance of the battle villancico, El más augusto campeón, and its historical, social, and musical contexts within the villancico genre of the Latin American Baroque. This study focuses on the villancico, El más augusto campeón, and explores the possible origins of the text and its relevance to the political and social structure of Cuzco's San Antonio Abad Seminary. Other areas of investigation are the musical analysis of the score and performance practice issues that surface when making choices as a conductor. Considering the seminal position villancicos held in the catechization of the Incans, in part due to their popular nature, the study of a representative example of this significant genre lends further insight into how important the villancico was to the ordinary and feast services of Peruvian (and, by association, Latin American) churches. While within the villancico's textual and musical structure one reads the obvious reflection of peninsular Spanish Catholic culture, its application to the criollo subculture carries an even more striking relevance.
Date: December 2009
Creator: Farris, Daniel
System: The UNT Digital Library
Investigating incidental vocabulary acquisition in ESL conversation classes. (open access)

Investigating incidental vocabulary acquisition in ESL conversation classes.

This study examined incidental receptive and productive vocabulary gains within conversation-class interactions. Eleven Mexican learners of English attended four videotaped conversation lessons where 40 target words were incorporated in different types of exposure. Stimulated recall interviews with students highlighted the effect of cognates, learners' access to passive vocabulary, and use of their vocabulary knowledge in learning related words. Posttests revealed a correlation between frequency and receptive/productive gains. Mean scores showed that words mentioned with synonyms were learned most often, followed by task-essential words and last those mentioned without explanation. A two-way ANCOVA revealed main effects for cognates, and a statistical interaction between cognate status and types of exposure. A statistical correlation was found between receptive and productive gains. Aptitude scores correlated with productive gains but not with receptive gains. The results provide implications for ESL teachers who consider incidental learning of vocabulary within their conversation lessons.
Date: December 2009
Creator: Mohamed, Ayman Ahmed Abdelsamie
System: The UNT Digital Library
An investigation into graph isomorphism based zero-knowledge proofs. (open access)

An investigation into graph isomorphism based zero-knowledge proofs.

Zero-knowledge proofs protocols are effective interactive methods to prove a node's identity without disclosing any additional information other than the veracity of the proof. They are implementable in several ways. In this thesis, I investigate the graph isomorphism based zero-knowledge proofs protocol. My experiments and analyses suggest that graph isomorphism can easily be solved for many types of graphs and hence is not an ideal solution for implementing ZKP.
Date: December 2009
Creator: Ayeh, Eric
System: The UNT Digital Library
An Investigation Into the Factors Leading to the Closure of 40 Private Four-Year Colleges between 1965 and 2005 (open access)

An Investigation Into the Factors Leading to the Closure of 40 Private Four-Year Colleges between 1965 and 2005

This study searches for a set of common indicators that contributed to the ultimate closure of 40 colleges and universities between 1965 and 2005. From research on related literature, a set of 31 contributing factors was identified by published experts and observers in higher education. That set of indicators was then used as a list of 31 questions answered by data found in newspaper articles, professional journals, published research work, published institutional records, data taken from the Department of Education, data taken from IPEDS, data published in historical recounts of the colleges of interest, etc. The data was accumulated in the form of yes/no responses to the 31 questions. Although the study involved only 40 colleges and universities this population represents the majority of institutions that pass the restrictions of limitations and delimitations described in the full document. The complete data set was processed using SPSS which produced ANOVA tables and level of statistical significance for each indicator question. The results indicate that out of the 31 original indicator questions there were two groups of statistically significant indicators. The larger group of indicators having statistical significance at the .05 level encompassed the smaller group having statistical significance at the .001 …
Date: December 2009
Creator: Province, Terry Paul
System: The UNT Digital Library
Investigation of cryopreservation methods for adherent nerve cell networks in vitro. (open access)

Investigation of cryopreservation methods for adherent nerve cell networks in vitro.

Cryopreservation in suspension is commonplace for a variety of cell types. However, cryopreservation of adherent cells has achieved limited success. This research aimed to cryopreserve adherent nerve cell networks in vitro in a manner that preserved network morphology and physiology. Successful implementation would enable long term storage of adherent neuronal networks on microelectrode arrays and on-demand access for use in pharmacological and toxicological testing. Based upon morphological assessments, excellent post-thaw preservation was obtained and post-thaw cultures survived in a transitional medium for up to 3.5 hours. However, transitions to native culture medium post-thaw presented difficulties, ultimately resulting in necrosis. A discussion of methods to supplement the current research and increase post-thaw viability is included in the thesis.
Date: December 2009
Creator: Webb, Veronica Fine
System: The UNT Digital Library
Latent Transition Analysis of Pre-service Teachers' Efficacy in Mathematics and Science (open access)

Latent Transition Analysis of Pre-service Teachers' Efficacy in Mathematics and Science

This study modeled changes in pre-service teacher efficacy in mathematics and science over the course of the final year of teacher preparation using latent transition analysis (LTA), a longitudinal form of analysis that builds on two modeling traditions (latent class analysis (LCA) and auto-regressive modeling). Data were collected using the STEBI-B, MTEBI-r, and the ABNTMS instruments. The findings suggest that LTA is a viable technique for use in teacher efficacy research. Teacher efficacy is modeled as a construct with two dimensions: personal teaching efficacy (PTE) and outcome expectancy (OE). Findings suggest that the mathematics and science teaching efficacy (PTE) of pre-service teachers is a multi-class phenomena. The analyses revealed a four-class model of PTE at the beginning and end of the final year of teacher training. Results indicate that when pre-service teachers transition between classes, they tend to move from a lower efficacy class into a higher efficacy class. In addition, the findings suggest that time-varying variables (attitudes and beliefs) and time-invariant variables (previous coursework, previous experiences, and teacher perceptions) are statistically significant predictors of efficacy class membership. Further, analyses suggest that the measures used to assess outcome expectancy are not suitable for LCA and LTA procedures.
Date: December 2009
Creator: Ward, Elizabeth Kennedy
System: The UNT Digital Library
Laying the foundation for successful non-academic writing: Professional communication principles in the K-5 curricula of the McKinney Independent School District. (open access)

Laying the foundation for successful non-academic writing: Professional communication principles in the K-5 curricula of the McKinney Independent School District.

Traditionally, K-5 students' writing has had a primarily academic aim-to help students master concepts and express themselves. Even if students take a professional writing course later, they typically do not have the opportunity to practice-over the long period of time mastery requires-the non-academic writing skills they will be required to use as part of their jobs and in their civic life. Based on a limited K-5 study, Texas' McKinney Independent School District is doing a good job of preparing students at the elementary-school level in the areas of collaboration and presentation. A fair job of helping elementary-school students understand the communication situation, define audience, clarify purpose, gather and evaluate resources, and test usability. [And] a poor job of helping elementary-school students with analysis and organization. With their teachers' help, K-5 students eventually grasp the communication situation and can broadly identify their audience and purpose, but they do not appear to select words, format, communication style, or design based on that audience and purpose. Their writer-based focus affects their presentations as well, although they do present frequently. If teachers routinely incorporated audience and purpose considerations into every aspect of communication assignments (format, communication style, design), students would be better prepared for …
Date: December 2009
Creator: Treviño, Marlea
System: The UNT Digital Library
Letters, Liberty, and the Democratic Age in the Thought of Alexis de Tocqueville (open access)

Letters, Liberty, and the Democratic Age in the Thought of Alexis de Tocqueville

When Alexis de Tocqueville observed the spread of modern democracy across France, England, and the United States, he saw that democracy would give rise to a new state of letters, and that this new state of letters would influence how democratic citizens and statesmen would understand the new political world. As he reflected on this new intellectual sphere, Tocqueville became concerned that democracy would foster changes in language and thought that would stifle concepts and ideas essential to the preservation of intellectual and political liberty. In an effort to direct, refine, and reshape political thought in democracy, Tocqueville undertook a critique of the democratic state of letters, assessing intellectual life and contributing his own ideas and concepts to help citizens and statesmen think more coherently about democratic politics. Here, I analyze Tocqueville's critique and offer an account of his effort to reshape democratic political thought. I show that through his analyses of the role of intellectuals in democratic regimes, the influence of modern science on democratic public life, the intellectual habits that democracy fosters, and the power of literary works for shaping democratic self-understanding, Tocqueville succeeds in reshaping democratic language and thought in a manner that contributes to the preservation …
Date: December 2009
Creator: Elliot, Natalie J.
System: The UNT Digital Library
Level Curves of the Angle Function of a Positive Definite Symmetric Matrix (open access)

Level Curves of the Angle Function of a Positive Definite Symmetric Matrix

Given a real N by N matrix A, write p(A) for the maximum angle by which A rotates any unit vector. Suppose that A and B are positive definite symmetric (PDS) N by N matrices. Then their Jordan product {A, B} := AB + BA is also symmetric, but not necessarily positive definite. If p(A) + p(B) is obtuse, then there exists a special orthogonal matrix S such that {A, SBS^(-1)} is indefinite. Of course, if A and B commute, then {A, B} is positive definite. Our work grows from the following question: if A and B are commuting positive definite symmetric matrices such that p(A) + p(B) is obtuse, what is the minimal p(S) such that {A, SBS^(-1)} indefinite? In this dissertation we will describe the level curves of the angle function mapping a unit vector x to the angle between x and Ax for a 3 by 3 PDS matrix A, and discuss their interaction with those of a second such matrix.
Date: December 2009
Creator: Bajracharya, Neeraj
System: The UNT Digital Library
The List (open access)

The List

The List is a collection of short stories focusing on the inability to adapt, or learn from self-destructive patterns, and the bizarre ways people reach out for one another when they don't know what else to do.
Date: December 2009
Creator: O'Brien, Tanner Chase
System: The UNT Digital Library
A Longitudinal Examination of Factors Associated with Custodial Grandparenting: A Test of Moderated Mediation (open access)

A Longitudinal Examination of Factors Associated with Custodial Grandparenting: A Test of Moderated Mediation

The purpose of this study was to explore the following relationships: (a) how moderating factors (gender, age, ethnicity, social support, marital status, reason for role assumption and number of grandchildren in the home) can influence the mediating role of resiliency, and (b) how resiliency may mediate the negative effects of raising grandchildren (role demands, life disruptions, and difficulties with grandchildren) on grandparent adjustment over time. Resiliency was hypothesized to have the greatest effect on custodial grandparents who experienced the most stress (i.e., older, single, Caucasian males lacking social support and raising more than one grandchild). Mediation was assessed using structural equation modeling. Results indicated resilience mediated the relationship between role assumptions (i.e., role demands and life disruptions) and grandparent adjustment; however, resilience did not mediate the relationship between grandchild characteristics and grandparent adjustment. Due to the small number of custodial grandfathers (n = 14), non-married grandparents (n = 29), non-Caucasian grandparents (n = 10), the small number of grandparents who assumed the custodial role for less ambiguous reasons (n = 24), and the number of custodial grandparents with more than one grandchild residing in the home (n = 29) participating within the study, hierarchical multiple regressions were only conducted to …
Date: December 2009
Creator: Moske, Amanda Kay
System: The UNT Digital Library
The Map and the Territory in the Poetry of Wallace Stevens (open access)

The Map and the Territory in the Poetry of Wallace Stevens

In this dissertation, Wallace Stevens' imagination-reality problem as depicted in his poetry is discussed in terms of an eco-critical map-territory divide. Stevens's metaphor of "the necessary angel" acts to mediate human necessity, the map, with natural necessity, the territory, in order to retain contact with changing cultural and environmental conditions. At stake in this mediation are individual freedom and the pertinence of the imagination to the experience of reality. In Chapter 2, the attempt at reconciliation of these two necessities will be described in terms of surrealism. Stevens's particular approach to surrealism emphasizes separating and delineating natural necessity from human necessity so that through the poem the reader can experience the miracle of their reconciliation. In Chapter 3, this delineation of the two necessities, map and territory, will be examined against Modernist "decreation," which is the stripping bare of human perception for the purpose of regaining glimpses of the first idea of the external world. And in Chapter 4, Stevens's approach to the problem of the map-territory divide will be considered against his alienation or internal exile: balancing nature and identity through mediating fictions results in a compromised approach to the marriage of mind and culture in a historically situated …
Date: December 2009
Creator: Thompson, Erik Robb
System: The UNT Digital Library
Metabolic, cardiac and ventilatory regulation in early larvae of the South African clawed frog, Xenopus laevis. (open access)

Metabolic, cardiac and ventilatory regulation in early larvae of the South African clawed frog, Xenopus laevis.

Early development of O2 chemoreception and hypoxic responses under normoxic (150 mmHg) and chronically hypoxic (110 mmHg) conditions were investigated in Xenopus laevis from hatching to 3 weeks post fertilization. Development, growth, O2 consumption, ventilatory and cardiac performance, and branchial neuroepithelial cells (NEC) density and size were determined. At 3 days post fertilization (dpf), larvae started gill ventilation at a rate of 28 ± 4 beats/min and showed increased frequency to 60 ± 2 beats/min at a PO2 of 30 mmHg. Also at 3 dpf, NECs were identified in the gill filament buds using immunohistochemical methods. Lung ventilation began at 5 dpf and exhibited a 3-fold increase in frequency from normoxia to a PO2 of 30 mmHg. Hypoxic tachycardia developed at 5 dpf, causing an increase of 20 beats/min in heart rate, which led to a 2-fold increase in mass-specific cardiac output at a PO2 of 70 mmHg. At 10 dpf, gill ventilatory sensitivity to hypoxia increased, which was associated with the increase in NEC density, from 15 ± 1 to 29 ± 2 cells/mm of filament at 5 and 10 dpf, respectively. Unlike the elevated rate, cardiac and ventilatory volumes were independent of acute hypoxia. Despite increased cardioventilatory frequency, …
Date: December 2009
Creator: Pan, Tien-Chien
System: The UNT Digital Library
Moderators of the sociocultural internalization-body dissatisfaction relationship among female undergraduates. (open access)

Moderators of the sociocultural internalization-body dissatisfaction relationship among female undergraduates.

The sociocultural model of eating pathology is an empirically-supported model explaining eating disorder etiology. The model poses that body dissatisfaction and subsequent eating pathology stems from the unrealistic standards formulated by Westernized society. Although the model has strong empirical support, variables within the model do not account for 100% of the variance in disordered eating. Thus, the current researcher attempted to explore potential moderating factors in the sociocultural model of eating disorders that may help to explain variance currently unaccounted for. In particular, the researcher focused on the relationship between sociocultural internalization and body dissatisfaction, given that this relationship has not been previously explored within the literature. Based on theoretical support, the researcher chose several potential variables to test, including perfectionism, neuroticism, body surveillance, and shame. Primary analyses tested each variable for moderating effects using hierarchical moderated regression, but no significant findings were shown. Results of post hoc analyses showed all variables had significant mediating effects, with the exception of self-oriented perfectionism. The discussion section addresses consistency with previous research, limitations of the present study, treatment implications and guidelines for future research.
Date: December 2009
Creator: Latimer-Kern, Kelsey M.
System: The UNT Digital Library
Monitoring or moral hazard? Evidence from real activities manipulation by venture-backed companies. (open access)

Monitoring or moral hazard? Evidence from real activities manipulation by venture-backed companies.

Prior literature suggests two competing theories regarding the role of venture capitalists (VCs) in their portfolio companies. The VC monitoring hypothesis argues that VCs effectively resolve the managerial agency problem through close monitoring and restraining managers' earnings management behavior. The VC moral hazard hypothesis argues that VCs aggravate the private benefits agency problem by exerting influence over managers to artificially inflate exit stock price through earnings management. Using a sample of IPO firms between 1987 and 2002, after controlling for the magnitude of accruals manipulation (AM), I compare the magnitude of real activities manipulation (RM) between venture-backed and non-venture-backed companies. I find that relative to non-venture-backed companies, venture-backed companies show significantly less RM in the first post-IPO fiscal year. The results are robust after controlling for the VC selection endogeneity. The finding supports the VC monitoring hypothesis that VCs restrain managers' RM behavior. Furthermore, I document that venture-backed companies exhibit a significant difference from non-venture-backed companies only in the first post-IPO fiscal year. The difference between the two groups in either the IPO year or the second post-IPO fiscal year is not significant, or at best, is weak. This finding is consistent with the argument that VCs tighten their control …
Date: December 2009
Creator: Liu, Xiang
System: The UNT Digital Library
Natural concepts in the domestic dog. (open access)

Natural concepts in the domestic dog.

The current study investigated concept formation in domestic dogs, specifically that of a toy concept. The dog's differential responding (retrieval vs. non-retrieval) to two sets of stimuli suggested a toy concept. Differential responding occurred from the very first trial, indicating that the concept had been formed in the natural environment, not during the experiment. It was hypothesized that a common response may be responsible for the emergence of the class in the natural environment. The results demonstrated that it was possible to expand the class by adding previously non-retrieved objects to the toy class through a common response. It was also shown that the toy concept passed the more stringent criterion (transfer of function test) required validating it as a concept.
Date: December 2009
Creator: Feuerbacher, Erica Nan
System: The UNT Digital Library
Needs and Membership in Terrorist Organizations (open access)

Needs and Membership in Terrorist Organizations

One key to reducing terrorism may be to understand why individuals join terror groups, and to find ways to meet their needs through alternatives to discourage membership in terrorist organizations. The study introduces the hierarchy of needs framework to capture all previous pieces of explanations on why individuals join terror groups under one big umbrella, in order to see the big picture. It does not do a meta-analysis, but rather tests the framework. This study is designed to find out what perceived needs commonly motivate individuals to join terror groups in general and specific terror groups in particular. The research uses Turkey's terrorism experience as a case study which is supported with data from real terrorist in Turkey. Findings of the descriptive analyses show that majority joined a terror group due to social and affiliative needs. The remaining analyses (bivariate, cross-tabulation and binary logistic regression) show that confitents who perceived esteem and recognition were more likely to become members of other/leftist terror groups, and that rightist terror group members in Turkey tend to have higher education. Education mainly affects a confitent's perception of two needs: social and affiliation and self-actualization. Other demographic variables (age group, region of birth, marital status) …
Date: December 2009
Creator: Ekici, Siddik
System: The UNT Digital Library
Negative affect and positive symptoms of psychosis. (open access)

Negative affect and positive symptoms of psychosis.

The current study utilized structural equation modeling (SEM) to examine the factor-to-factor relations and temporal associations between disturbances in negative affect (NA) and positive symptoms of psychosis (PP). Data were drawn from a large, public-domain data set (MacArthur Violence Risk Assessment Study). A dimensional approach was used to conceptualize and identify latent variables of NA (depression, anxiety, and guilt) and PP (hallucinations, delusions, and thought disorder) among individuals with a diagnosis of primary psychotic disorder. Results showed that anxiety, guilt, and depressed mood modeled an NA latent variable, and that hallucinations and unusual thought content modeled a PP latent variable. As predicted, results revealed strong, significant cross-sectional (synchronous) associations between NA and PP at each measured time-frame, suggesting that NA and PP occurred concurrently within the sample. Contrary to predictions, no significant cross-lagged effect between NA and PP was identified (10 weeks and 20 weeks respectively).
Date: December 2009
Creator: Crutchfield, Audra
System: The UNT Digital Library
Negotiating Interests: Elizabeth Montagu's Political Collaborations with Edward Montagu; George, Lord Lyttelton; and William Pulteney, Lord Bath (open access)

Negotiating Interests: Elizabeth Montagu's Political Collaborations with Edward Montagu; George, Lord Lyttelton; and William Pulteney, Lord Bath

This dissertation examines Elizabeth Robinson Montagu's relationships with three men: her husband, Edward Montagu; George Lyttelton, first baron Lyttelton; and William Pulteney, earl of Bath to show how these relationships were structured and how Elizabeth Montagu negotiated them in order to forward her own intellectual interests. Montagu's relationship with her husband Edward and her friendships with Lord Lyttelton and Lord Bath supplied her with important outlets for intellectual and political expression. Scholarly work on Montagu's friendships with other intellectual women has demonstrated how Montagu drew on the support of female friends in her literary ambitions, but at the same time, it has obscured her equally important male relationships. Without discounting the importance of female friendship to Montagu's intellectual life, this study demonstrates that Montagu's relationships with Bath, Lyttleton, and her husband were at least as important to her as those with women, and that her male friendships and relationships offered her entry into the political sphere. Elizabeth Montagu was greatly interested in the political debates of her day and she contributed to the political process in the various ways open to her as an elite woman and female intellectual. Within the context of these male friendships, Montagu had an opportunity …
Date: December 2009
Creator: Bennett, Elizabeth Stearns
System: The UNT Digital Library
A New N-way Reconfigurable Data Cache Architecture for Embedded Systems (open access)

A New N-way Reconfigurable Data Cache Architecture for Embedded Systems

Performance and power consumption are most important issues while designing embedded systems. Several studies have shown that cache memory consumes about 50% of the total power in these systems. Thus, the architecture of the cache governs both performance and power usage of embedded systems. A new N-way reconfigurable data cache is proposed especially for embedded systems. This thesis explores the issues and design considerations involved in designing a reconfigurable cache. The proposed reconfigurable data cache architecture can be configured as direct-mapped, two-way, or four-way set associative using a mode selector. The module has been designed and simulated in Xilinx ISE 9.1i and ModelSim SE 6.3e using the Verilog hardware description language.
Date: December 2009
Creator: Bani, Ruchi Rastogi
System: The UNT Digital Library
A New Wireless Sensor Node Design for Program Isolation and Power Flexibility (open access)

A New Wireless Sensor Node Design for Program Isolation and Power Flexibility

Over-the-air programming systems for wireless sensor networks have drawbacks that stem from fundamental limitations in the hardware used in current sensor nodes. Also, advances in technology make it feasible to use capacitors as the sole energy storage mechanism for sensor nodes using energy harvesting, but most current designs require additional electronics. These two considerations led to the design of a new sensor node. A microcontroller was chosen that meets the Popek and Goldberg virtualization requirements. The hardware design for this new sensor node is presented, as well as a preliminary operating system. The prototypes are tested, and demonstrated to be sustainable with a capacitor and solar panel. The issue of capacitor leakage is considered and measured.
Date: December 2009
Creator: Skelton, Adam W.
System: The UNT Digital Library
No Title IX in Journalism: An Analysis of Subject Gender in Newspaper Sports Columns (open access)

No Title IX in Journalism: An Analysis of Subject Gender in Newspaper Sports Columns

The purpose of this study is to examine gender bias in sports media from the perspective of the sports columnist. The research analyzed 1,082 sports columns written by ten columnists (five male, five female) at newspapers across the United States. The columns were scrutinized to determine if the column subject was male or female. Results found that 84.4% of the sports columns were written about male athletes or men's sports compared to only 9% devoted to female athletes and women's sports. The research also found that female sports columnists write about female sports 12.7% of the time, while male sports columns only dedicate 6% of their columns to female athletes or women's sports. Newspapers with a larger circulation were more likely to have sports columns about female sports than were newspapers with smaller readerships. Six of the columnists were then interviewed to get their opinions on gender issues in sports journalism.
Date: December 2009
Creator: Bostic, Jordan
System: The UNT Digital Library