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 Collection: UNT Theses and Dissertations
Central Office Administrators' Perceptions of the Professional Learning Community Process

Central Office Administrators' Perceptions of the Professional Learning Community Process

Date: August 2013
Creator: Pruitt, Mary E.
Description: This study provides a qualitative interpretation of the work done by central office administrators in a school district in Texas as they supported and built capacity for the professional learning community (PLC) process over a five year time period. Literature by PLC scholars, especially R. DuFour, R.B. DuFour, Eaker, Hord, Hipp, Huffman, and Olivier, informed development of the study. In a school district of 19,000 students and 2,000 staff members, ten central office administrators were interviewed to gain their perceptions of their roles in the PLC process. Interviews were analyzed through the processes of initial, focused, and theoretical coding. Documents were examined and used as supplemental sources of data to corroborate the perspectives provided. Findings revealed the story of central office administrators who worked interdependently to support and build capacity in the implementation and sustainment of the PLC process. A thick description of the work based on their perceptions offers actions and behaviors of administrators specific to their roles and practices and protocols developed to hold the work together. A grounded theory was developed with regard to central office administrators' support and capacity-building for the PLC process. From the administrators' perceptions, six theoretical categories relating to central office support and ...
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Comparative Phyto-uptake Across Distribution Coefficients of Pharmaceutical Compounds and Aquatic Macrophytes: Carbamazepine and Amiodarone Uptake in Lemna Spp

Comparative Phyto-uptake Across Distribution Coefficients of Pharmaceutical Compounds and Aquatic Macrophytes: Carbamazepine and Amiodarone Uptake in Lemna Spp

Date: August 2013
Creator: Woodard, Jennifer Kristin
Description: Few studies have been conducted on the effectiveness of phytoremediation of pharmaceutical compounds, although the persistent and non-acutely toxic nature of many of these compounds in today's water bodies may yield an ideal application for this practice. To quantify the potential effectiveness of plant uptake, kinetic and proportional bioconcentration factors (BCFk, and BCFp, respectively) in nanograms (ng) carbamazepine and amiodarone per gram (g) wet weight plant tissue for Lemna spp. were determined utilizing a 14-day continuous flow-through study. Samples were analyzed using isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) running in positive ion mode. Kinetic BCF was estimated at 0.538, while proportional BCF was estimated at 0.485. Kinetic BCF for the amiodarone study was estimated at 23.033, whereas proportional BCF was estimated at 41.340. Possible contamination of the C18 column and peristaltic pump failure may have impacted uptake results. In light of variability and current lack of research in the field, this work should be considered exploratory rather than conclusive.
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A Comparative Study of Non Linear Conjugate Gradient Methods

A Comparative Study of Non Linear Conjugate Gradient Methods

Date: August 2013
Creator: Pathak, Subrat
Description: We study the development of nonlinear conjugate gradient methods, Fletcher Reeves (FR) and Polak Ribiere (PR). FR extends the linear conjugate gradient method to nonlinear functions by incorporating two changes, for the step length αk a line search is performed and replacing the residual, rk (rk=b-Axk) by the gradient of the nonlinear objective function. The PR method is equivalent to FR method for exact line searches and when the underlying quadratic function is strongly convex. The PR method is basically a variant of FR and primarily differs from it in the choice of the parameter βk. On applying the nonlinear Rosenbrock function to the MATLAB code for the FR and the PR algorithms we observe that the performance of PR method (k=29) is far better than the FR method (k=42). But, we observe that when the MATLAB codes are applied to general nonlinear functions, specifically functions whose minimum is a large negative number not close to zero and the iterates too are large values far off from zero the PR algorithm does not perform well. This problem with the PR method persists even if we run the PR algorithm for more iterations or with an initial guess closer to the ...
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Computational Studies of Inorganic Systems with a Multiscale Modeling Approach: From Atomistic to Continuum Scale

Computational Studies of Inorganic Systems with a Multiscale Modeling Approach: From Atomistic to Continuum Scale

Date: August 2013
Creator: Olatunji-Ojo, Olayinka A.
Description: Multiscale modeling is an effective tool for integrating different computational methods, creating a way of modeling diverse chemical and physical phenomena. Presented are studies on a variety of chemical problems at different computational scales and also the combination of different computational methods to study a single phenomenon. The methods used encompass density functional theory (DFT), molecular dynamics (MD) simulations and finite element analysis (FEA). The DFT studies were conducted both on the molecular level and using plane-wave methods. The particular topics studied using DFT are the rational catalyst design of complexes for C—H bond activation, oxidation of nickel surfaces and the calculation of interaction properties of carbon dioxide containing systems directed towards carbon dioxide sequestration studies. Second and third row (typically precious metals) transition metal complexes are known to possess certain electronic features that define their structure and reactivity, and which are usually not observed in their first-row (base metal) congeners. Can these electronic features be conferred onto first-row transition metals with the aid of non-innocent and/or very high-field ligands? Using DFT, the impact of these electronic features upon methane C—H bond activation was modeled using the dipyridylazaallyl (smif) supporting ligand for late, first-row transition metal (M) imide, oxo and ...
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Confirming the Constructs of the Adlerian Personality Priority Assessment (Appa)

Confirming the Constructs of the Adlerian Personality Priority Assessment (Appa)

Date: August 2013
Creator: Dillman Taylor, Dalena
Description: The primary purpose of this study was to confirm the four-factor structure of the 30-item Adlerian Personality Priority Assessment (APPA) using a split-sample cross-validation confirmatory factor analysis (CFA). The APPA is an assessment, grounded in Adlerian theory, used to conceptualize clients based on the four personality priorities most commonly used in the Adlerian literature: superiority, pleasing, control, and comfort. The secondary purpose of this study was to provide evidence for discriminant validity, examine predictive qualities of demographics, and explore the prevalence of the four priorities across demographics. For the cross validation CFA, I randomly divided the sample, 1210 undergraduates, at a large public research university (53% Caucasian, 13.1% Hispanic/Latino(a), 21.4% African American, 5.4% American Indian, and 5.8% biracial; mean age =19.8; 58.9% females), into two equal subsamples. I used Subsample 1 (n = 605) to conduct the initial CFA. I held out Subsample 2 (n = 605) to test any possible model changes resulting from Subsample 1 results and to provide further confirmation of the APPA's construct validity. Findings from the split-sample cross-validation CFA confirmed the four-factor structure of the APPA and provided support for the factorial/structure validity of the APPA's scores. Results also present initial evidence of discriminant validity ...
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Cooperation-induced Criticality in Neural Networks

Cooperation-induced Criticality in Neural Networks

Date: August 2013
Creator: Zare, Marzieh
Description: The human brain is considered to be the most complex and powerful information-processing device in the known universe. The fundamental concepts behind the physics of complex systems motivate scientists to investigate the human brain as a collective property emerging from the interaction of thousand agents. In this dissertation, I investigate the emergence of cooperation-induced properties in a system of interacting units. I demonstrate that the neural network of my research generates a series of properties such as avalanche distribution in size and duration coinciding with the experimental results on neural networks both in vivo and in vitro. Focusing attention on temporal complexity and fractal index of the system, I discuss how to define an order parameter and phase transition. Criticality is assumed to correspond to the emergence of temporal complexity, interpreted as a manifestation of non-Poisson renewal dynamics. In addition, I study the transmission of information between two networks to confirm the criticality and discuss how the network topology changes over time in the light of Hebbian learning.
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Correlates Between Adult Romantic Attachment Patterns and Dimensional Personality Pathology

Correlates Between Adult Romantic Attachment Patterns and Dimensional Personality Pathology

Date: August 2013
Creator: Ernest, Kimberly Dawn
Description: Previous research has suggested that adult attachment disturbance is related to maladaptic interaction patterns and personality disorder constructs. Specifically, research indicates that those with attachment disturbance are significantly more likely to meet criteria for a number of personality disorders, including borderline personality disorder, narcissistic personality disorder, and antisocial personality disorder. The purpose of this study was to investigate the associations between adult attachment and the new dimensional model of personality disorders scheduled to be released in the Diagnostic and Statistical Manual for Mental Health Diosrders (5th ed.) in spring 2013. Participants completed the Schedule for Adaptive and Nonadaptive Personality (SNAP) to measure dimensional personality functioning and the Experiences in Close Relationships (ECR-R) and the Attachment Prototypes to measure adult attachment patterns. Additionally, select scales from the Personality Assessment Inventory (PAI) and the Five Factor Model (FFM) will be utilized as secondary measures of personality patterns. The results suggest strong associations between adult attachment orientations and specific maladaptive personality characteristics.
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Corrosion Protection of Aerospace Grade Magnesium Alloy Elektron 43™ for Use in Aircraft Cabin Interiors

Corrosion Protection of Aerospace Grade Magnesium Alloy Elektron 43™ for Use in Aircraft Cabin Interiors

Date: August 2013
Creator: Baillio, Sarah S.
Description: Magnesium alloys exhibit desirable properties for use in transportation technology. In particular, the low density and high specific strength of these alloys is of interest to the aerospace community. However, the concerns of flammability and susceptibility to corrosion have limited the use of magnesium alloys within the aircraft cabin. This work studies a magnesium alloy containing rare earth elements designed to increase resistance to ignition while lowering rate of corrosion. The microstructure of the alloy was documented using scanning electron microscopy. Specimens underwent salt spray testing and the corrosion products were examined using energy dispersive spectroscopy.
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Deconstructing Webern's Op 25, Drei Lieder: a Multidimensional Assessment

Deconstructing Webern's Op 25, Drei Lieder: a Multidimensional Assessment

Date: August 2013
Creator: Morgeson, Paul Taylor
Description: Webern scholarship has not comprehensively examined op. 25, drei lieder. If the selection of text for op. 25 is viewed as one work in three movements they create a ternary form (A-B-A1). To show how this form is developed in the music the author creates a new analytical system based on Schoenberg's Grundgestalt which is defined by three basic ideas: symmetry, liquidation, and variation. The relationship between the voice and accompaniment and Webern's deliberate manipulation of the text is used to reveal the use of a program which is then tied to the numerical symbolism of 2 and 3.
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Design and Application of Phased Array System

Design and Application of Phased Array System

Date: August 2013
Creator: Ren, Han
Description: Since its invention, phased array has been extensively applied in both military and civil areas. The applications include target detecting and tracking, space probe communication, broadcasting, human-machine interfaces, and remote sensing. Although the phased array applications show a broad range of potential market, there are some limitations of phased array's development: high cost, complex structure, narrow bandwidth, and high power consumption. Therefore, novel ideas are needed to reduce these constraints. In this thesis, several new approaches about the design and application of phased array are presents. First, the principle of phased array and fundamental design equations are introduced. Second, a new application of phased array antenna for radar respiration measurement is presented. By integrating a 4×4 Butler matrix with four-element antenna array, there will be four distinct main beams in radiation pattern. This new approach can improve the measurement accuracy and realize a high detecting rate. Third, a compact phased array antenna system based on dual-band operations is introduced. Dual-band function can make N-antenna system obtain 2N unique radiation beams (N is an integer) and achieve a significant size reduction compared to the conventional single-band system. To verify the design concept, a four-element phased array antenna working at 5GHz and ...
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