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Dimensional Assessment of Empowerment in Organizations

Description: This research project was inspired by a survey that was designed to help an organization determine how well it was doing in its efforts to empower associates and achieve a goal of continuous improvement. Initial review of the survey created suspicion that the survey was not built around the appropriate dimensions to accurately measure the level of empowerment in organizations. As such, the survey was psychometrically analyzed to determine the validity of the instrument as a measure of empowerment. Additionally, an extensive review of the literature was performed to determine new dimensions that would most accurately measure empowerment. Eight dimensions (culture, trust, accountability, leadership, ability, commitment, responsibility, and communication) were put forth as the most appropriate to measure empowerment. Subject matter experts with knowledge and experience in the area of organizational empowerment reviewed the new dimensions for accuracy and fit with the original survey items.
Date: May 2003
Creator: Bodner, Sarah L.

Dimensions in Random Constructions.

Description: We consider random fractals generated by random recursive constructions, prove zero-one laws concerning their dimensions and find their packing and Minkowski dimensions. Also we investigate the packing measure in corresponding dimension. For a class of random distribution functions we prove that their packing and Hausdorff dimensions coincide.
Date: May 2002
Creator: Berlinkov, Artemi

Dimensions of Acculturation and Sexual Health among U.S. Hispanic Youth

Description: Hispanic youth living in the U.S. share a disproportionate burden of risk for HIV, other STIs, and teen pregnancies. They also tend to report lower rates of condom use and higher rates of inconsistent condom use than other racial/ethnic groups. Furthermore, immigrant Hispanic adolescents experience a unique burden of sexual risk compared to their non-immigrant counterparts. These negative sexual health outcomes can severely derail the overall health, social mobility, and life opportunities of these adolescents. Social researchers have tried to explain these sexual risk disparities using the concept of immigrant acculturation, which is broadly defined as the process of adopting the cultural values and beliefs of a host society. Immigrant acculturation has been shown to play a key role in shaping youth attitudes and behaviors, including sexual risk behaviors (see Lee & Hahm, 2010). Yet, studies have largely overlooked the contextual components of acculturation that have been proposed in theoretical literature, specifically characteristics of the immigrant's receiving community. Furthermore, studies have not adequately explored the influence of acculturation on two crucial measures of sexual risk: teen pregnancy norms and condom use. Therefore, the current dissertation consists of two unique studies that examine the influence of acculturation, at both the individual and neighborhood level, on Hispanic adolescent teen pregnancy norms and condom use over time. The aim is to fill these important gaps in the literature and expand on earlier explanations of the relationship between cultural, place, and long-term sexual health. Both studies use nationally-representative data from the National Longitudinal Study of Adolescent to Adult Health. Overall, findings suggest an immigrant advantage for both teen pregnancy norms and condom use, although this advantage functions differently for males and females. Furthermore, the studies demonstrate the importance of including contextual measures of acculturation into studies related to Hispanic adolescent sexual health.
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Date: August 2016
Creator: Driver, Nichola D

Dimensions of Quality : Teachers' Beliefs and Practices in Texas Public Prekindergartens

Description: This study explores beliefs and practices about standards of quality in Texas public prekindergartens as viewed from various perspectives, including prekindergarten teachers, administrators of prekindergarten programs, and families of prekindergarten students. These beliefs and practices are compared with widely-accepted national standards of quality for preschool programs.
Date: May 1998
Creator: Kelly, Katherine Taddie

Dimensions of Social Network Position As Predictors of Employee Performance.

Description: Research of social networks has revealed that certain components of network position can have an impact on organizational effectiveness, yet relatively little research has been conducted on network position and individual performance. This study sought to determine if a relationship exists between an employee's social network position and an individual's job performance. The participant organization was a network of individuals within an Information Technology (IT) department at a major defense company. A social network analysis (SNA) was conducted to determine the employee's network position, measured by centrality and constraint. Centrality refers to the extent to which an individual is connected to others. Constraint refers to how constrained or inhibited an individual is within the network. Performance was measured by annual appraisal ratings provided by the employee's supervisor. Hierarchical regression analysis was performed to determine relationships between the dependent variable (performance) and independent variables of centrality and constraint. Secondary variables also studied in relation to the model included education level, service years (tenure), job grade, and age. The overall model revealed 17% of variance explained. The primary predictors of network position, centrality and constraint, were not statistically significant predictors of performance ratings. Three variables, job grade, tenure and age, were found to be statistically significant predictors of employee performance. Further research is suggested to provide additional insight into the predictive value of these variables.
Date: August 2007
Creator: Burton, Paul

Dining at Ethnic-themed Restaurants: an Investigation of Consumers' Ethnic Experiences, Preference Formation, and Patronage

Description: Given unprecedented shifts in the U.S. demography marked by rapid growth in Hispanic, Asian and other ethnic market segments, marketing scholars and practitioners are confronting ways to cultivate ethnic consumers' brand preference formation, retail patronage and their ensuring consumption choices. Food is cited as a common signifier for consumers’ ethnic/cultural identity because food itself is a cultural symbol. However, little research has examined the influences of ethnic identities on consumers’ patronage behaviors of ethnic-themed restaurants. Thus, this dissertation critically explores the impact of ethnic identity and motivational factors to better understand consumers' choices of ethnic-themed restaurants with a mix-method approach. The present research investigates how ethnic identity and consumers’ need for uniqueness interplay with perceived authenticity in consumers’ patronage intention of ethnic-themed restaurants. The findings advocate the interplay among ethnic identity, consumers’ need for uniqueness, and perceived authenticity of general consumers in decision making choices of patronizing ethnic-themed restaurants. The findings have important implications for market segmentation guiding the owners of ethnic-themed restaurant the choice of environmental cues to encourage patronage intentions among general consumers. Furthermore, this study provides additional insights about motivating factors affecting decision making of patronizing ethnic-themed restaurants and contributes to the stream of research by enhancing understanding of marketing ethnic-themed restaurant in a multi-cultural society.
Date: August 2014
Creator: Gai, Lili

Diphenyloxazole Metabolism by Aryl Hydrocarbon Hydroxylase

Description: 2,5-Diphenyloxazole (PPO) was tested as a potential alternate inducer for the aryl hydrocarbon hydroxylase (AHH) system. Its apparent lack. of carcinogenicity and toxicity provide a possible system for investigation of enzyme systems related to chemical carcinogenesis without exposure of the researcher to potent carcinogenic compounds. These studies found PPO to be an inducer of AHH in cultured human lymphocytes. When PPO was utilized as a substrate for the AHH assay system, the major metabolites produced were strongly fluorescent. A simple fluorometric assay was developed which employed PPO as the substrate and which measured constitutive activity more efficiently than similar assays using benzo(a)pyrene as the substrate. Quantitation of both basal and induced lymphocyte AHH metabolism of PPO may be applicable to human population studies and may provide a tool to determine possible genetic variables with respect to carcinogen metabolism related to cancer risk.
Date: December 1976
Creator: Abreu, Mary E.

Diphosphine Ligand Activation Studies with Organotransition-Metal Compounds

Description: Thermolysis of CoRu(CO)7(m -PPh2) (1) in refluxing 1,2-dichloroethane in the presence of the diphosphine ligands 2,3-bis(diphenylphosphino)maleic anhydride (bma) and 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) furnishes the new mixed-metal complexes CoRu(CO)4(μ -P-P)(μ -PPh2) [where P-P = bma (3); bpcd (6)], along with trace amounts of the known complex CoRu(CO)6(PPh3)(μ -PPh2) (4). The requisite pentacarbonyl intermediates CoRu(CO)5(μ -P-P)(μ -PPh2) [where P-P = bma (2); bpcd (5)] have been prepared by separate routes and studied for their conversion to CoRu(CO)4(μ -P-P)(μ -PPh2). The complexes 2/3 and 5/6 have been isolated and fully characterized in solution by IR and NMR spectroscopy. The kinetics for the conversion of 2→3 and of 5→6 were measured by IR spectroscopy in chlorobenzene solvent. On the basis of the first-order rate constants, CO inhibition, and the activation parameters, a mechanism involving dissociative CO loss as the rate-limiting step is proposed. The solid-state structure of CoRu(CO)4(μ -bma)(μ -PPh2) (3) reveals that the two PPh2 groups are bound to the ruthenium center while the maleic anhydride π bond is coordinated to the cobalt atom. Thermolysis of the cluster Ru3(CO)12 with the bis(phosphine)hydrazine ligand (MeO)2PN(Me)N(Me)P(OMe)2 (dmpdmh) in toluene at 75°C furnishes the known clusters Ru4(CO)12[μ -N(Me)N(Me)] (9) and Ru3(CO)11[P(OMe)3] (10), in addition to the new cluster Ru3(CO)10(dmpdmh) (8) and the phosphite-tethered cluster Ru3(CO)9[μ -P(OMe)3] (11). The simple substitution product Ru3(CO)10(dmpdmh), a logical intermediate to clusters 9-11, was synthesized by treating Ru3(CO)12 and dmpdmh with Me3NO in CH2Cl2 at room temperature, and independent thermolysis reactions using cluster 8 were shown to yield clusters 9-11. The tetrahedrane cluster FeCo2(CO)9(μ3-S) reacts with the redox-active ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) to give the disubstituted cluster FeCo2(CO)7(bpcd)(μ3-S) as the sole product. This diphosphine-substituted cluster contains a cobalt-bound, chelating bpcd ligand. The solid-state structure has been unequivocally established by X-ray diffraction analysis. Cyclic voltammetric studies on FeCo2(CO)7(bpcd)(μ3-S) reveal the presence of two quasireversible ...
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Date: December 2000
Creator: Wang, Jiancheng

Diphosphine Ligand Substitution in H4Ru4(CO)12: X-ray Diffraction Structures and Reactivity Studies of the Diphosphine Substituted Cluster Products

Description: The tetraruthenium cluster H4Ru4(CO)12 has been studied for its reactivity with the unsaturated diphosphine ligands (Z)-Ph2PCH=CHPPh2, 4,5-bis (diphenylphosphino)-4-cyclopenten-1,3-dione, bis(diphenyphosphino)benzene and 1,8- bis(diphenyl phosphino)naphthalene under thermal, near-UV photolysis, and Me3NO-assisted activation. All three cluster activation methods promote loss of CO and furnish the anticipated substitution products that possess a chelating diphosphine ligand. Clusters 1, 2, 3 and 4 have been characterized in solution by IR and NMR spectroscopies, and these data are discussed with respect to the crystallographically determined structures for all new cluster compounds. The 31P NMR spectral data and the solid-state structures confirm the presence of a chelating diphosphine ligand in all four new clusters. Sealed NMR tubes containing clusters 1, 2, 3 and 4 were found to be exceeding stable towards near-UV light and temperatures up to ca. 100°C. The surprisingly robust behavior of the new clusters is contrasted with the related cluster Ru3(CO)10(bpcd) that undergoes fragmentation to the donor-acceptor compound Ru2(CO)6(bpcd) and the phosphido-bridged compound Ru2(CO)6 (µ-PPh2)[µ-C=C(PPh2)C(O)CH2C(O)] under mild conditions. The electrochemical properties have been investigated in the case of clusters 1 and 2 by cyclic voltammetry, and the findings are discussed with respect to the reported electrochemical data on the parent cluster H4Ru4(CO)12.
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Date: December 2006
Creator: Kandala, Srikanth

The Diplomacy of an Army: the American Expeditionary Force in France, 1917-1918

Description: The entry of the United States into the Great War was enthusiastically endorsed by Congress on April 3, 1917. Even after the declaration of war, however, the exact nature of American participation was unclear. This thesis examines the role of American involvement in the war, as it responded to requests for support from Great Britain and France.
Date: June 1970
Creator: Owens, E. H.

The Diplomacy of Prohibition

Description: The advent of prohibition in America in the early 1920's brought on wide-spread smuggling activity along the Canadian and Mexican borders as well as along the Atlantic coastline. Since many of the smuggling vessels sought protection from American authorities by foreign registry, the State Department initiated efforts to enable American officials to enforce prohibition without interfering with legitimate commerce. Washington concluded compromise agreements with fifteen countries that provided for American enforcement measures and suitable liquor cargo arrangements for the other signatory nations. The liquor conventions were not a final solution to the smuggling problem but they did provide for better enforcement. The agreements reinforced existing principles and represented an attempt to eliminate possible sources of friction on the international level arising out of American prohibition enforcement.
Date: May 1976
Creator: Walker, Judson Steely

Diplomacy Rhetoric and the Human Rights Appeals of Jeane J. Kirkpatrick and Vernon A. Walters

Description: This thesis investigates the extent to which Ambassador Kirkpatrick's and Ambassador Walters' United Nations discourses on human rights reflects the rhetorical themes of "prophetic dualism" and "technocratic realism." A metaphoric analysis of six speeches reveals that both Kirkpatrick's and Walters' arguments were framed through an ideological division between Democracy and Communism. The presence of "prophetic dualism" in Kirkpatrick's and Walters' discourses is explained as an extension of President Reagan's bipolar rhetoric on world affairs. The presence of "technocratic realism" in Walters' discourse is described as resulting from a unique set of political and rhetorical factors. The exacting nature of "prophetic dualism" may make it ill suited as a method of argument in the realm of diplomacy.
Date: May 1991
Creator: Rogina, Sergio A. (Sergio Armando)

Dipole Moments of Diphenyl Compounds with Conjugated Double Bonds

Description: This thesis is a continuation of a study of molecular moments begun by Joseph T. Fielder. In his paper he discussed the theory and the equipment necessary for such a study. It is the purpose of this paper to set forth modifications of his equipment, to present data obtained with this modified equipment, and to interpret this data.
Date: 1950
Creator: Spalding, Dan W.

Direct and Indirect Effects of Parenting Style with Child Temperament, Parent-Child Relationship, and Family Functioning on Child Social Competence in the Chinese Culture: Testing the Latent Models

Description: Interactional and contextual models have been conceptually proposed in understanding parental influences on children. Yet, empirical model testing has been limited. The purpose of this exploratory study was to investigate the direct and indirect effects of parenting style on child social competence using structural equation modeling in a sample of 544 Chinese families with 6-9 years old children, mainly singleton, residing in Nanjing, China. Five latent models were tested: (a) the direct model between parenting style and child social competence, (b) child temperament as a moderator, (c) parent-child relationship as a mediator, (d) the interaction model between parenting style and family functioning, and (e) bidirectional models of parenting style concurrently with parent-child relationship, and family functioning predicting child social competence. Findings showed: (a) The direct relationship between parenting style and child social competence was significant in both parents with authoritative parenting style on the positive direction, whereas authoritarian and permissive parenting styles on the negative direction; (b) child temperament did not moderate parenting style on child social competence; (c) father-child relationship mediated paternal parenting style on child social competence, whereas maternal parenting style did not; (d) family functioning neither moderated nor mediated the relationship between parenting style and child social competence for both parents; and (e) The four-factor prediction models on child social competence turned out to be unidirectional. For the mothers, the best model was from family functioning to mother-child relationship, to maternal parenting style, and finally to child social competence. Maternal parenting style was the significant proximal factor. For the fathers, it was from family functioning to paternal parenting style, to father-child relationship, and then to child social competence. Father-child relationship had the direct impact, whereas the influence of paternal parenting style was distal through father-child relationship. Findings from this study suggest that the Chinese parents should use ...
Date: May 2007
Creator: Xu, Changkuan

Direct Atomic Level Controlled Growth and Characterization of h-BN and Graphene Heterostructures on Magnetic Substrates for Spintronic Applications

Description: Epitaxial multilayer h-BN(0001) heterostructures and graphene/h-BN heterostructures have many potential applications in spintronics. The use of h-BN and graphene require atomically precise control and azimuthal alignment of the individual layers in the structure. These in turn require fabrication of devices by direct scalable methods rather than physical transfer of BN and graphene flakes, and such scalable methods are also critical for industrially compatible development of 2D devices. The growth of h-BN(0001) multilayers on Co and Ni, and graphene/h-BN(0001) heterostructures on Co have been studied which meet these criteria. Atomic Layer Epitaxy (ALE) of BN was carried out resulting in the formation of macroscopically continuous h-BN(0001) multilayers using BCl3 and NH3 as precursors. X-ray photoemission spectra (XPS) show that the films are stoichiometric with an average film thickness linearly proportional to the number of BCl3/NH3 cycles. Molecular beam epitaxy (MBE) of C yielded few layer graphene in azimuthal registry with BN/Co(0001) substrate. Low energy electron diffraction (LEED) measurements indicate azimuthally oriented growth of both BN and graphene layers in registry with the substrate lattice. Photoemission data indicate B:N atomic ratios of 1:1. Direct growth temperatures of 600 K for BN and 800 to 900 K for graphene MBE indicate multiple integration schemes for applications in spintronics.
Date: August 2016
Creator: Beatty, John D.

Direct Immersion Cooling Via Nucleate Boiling of HFE-7100 Dielectric Liquid on Hydrophobic and Hydrophilic Surfaces

Description: This study experimentally investigated the effect of hydrophobic and hydrophilic surfaces characteristics on nucleate boiling heat transfer performance for the application of direct immersion cooling of electronics. A dielectric liquid, HFE – 7100 was used as the working fluid in the saturated boiling tests. Twelve types of 1-cm2 copper heater samples, simulating high heat flux components, featured reference smooth copper surface, fully and patterned hydrophobic surface and fully and patterned hydrophilic surfaces. Hydrophobic samples were prepared by applying a thin Teflon coating following photolithography techniques, while the hydrophilic TiO2 thin films were made through a two step approach involving layer by layer self assembly and liquid phase deposition processes. Patterned surfaces had circular dots with sizes between 40 – 250 μm. Based on additional data, both hydrophobic and hydrophilic surfaces improved nucleate boiling performance that is evaluated in terms of boiling incipience, heat transfer coefficient and critical heat flux (CHF) level. The best results, considering the smooth copper surface as the reference, were achieved by the surfaces that have a mixture of hydrophobic/hydrophilic coatings, providing: (a) early transition to boiling regime and with eliminated temperature overshoot phenomena at boiling incipience, (b) up to 58.5% higher heat transfer coefficients, and (c) up to 47.4% higher CHF levels. The studied enhanced surfaces therefore demonstrated a practical surface modification method for heat transfer enhancement in immersion cooling applications.
Date: December 2014
Creator: Joshua, Nihal E.

Direct Inject Mass Spectrometry for Illicit Chemistry Detection and Characterization

Description: The field of direct inject mass spectrometry includes a massive host of ambient ionization techniques that are especially useful for forensic analysts. Whether the sample is trace amounts of drugs or explosives or bulk amounts of synthetic drugs from a clandestine laboratory, the analysis of forensic evidence requires minimal sample preparation, evidence preservation, and high sensitivity. Direct inject mass spectrometry techniques can rarely provide all of these. Direct analyte-probed nanoextraction coupled to nanospray ionization mass spectrometry, however, is certainly capable of achieving these goals. As a multifaceted tool developed in the Verbeck laboratory, many forensic applications have since been investigated (trace drug and explosives analysis). Direct inject mass spectrometry can also be easily coupled to assays to obtain additional information about the analytes in question. By performing a parallel artificial membrane assay or a cell membrane stationary phase extraction prior to direct infusion of the sample, membrane permeability data and receptor activity data can be obtained in addition to the mass spectral data that was already being collected. This is particularly useful for characterizing illicit drugs and their analogues for a biologically relevant way to schedule new psychoactive substances.
Date: May 2016
Creator: Williams, Kristina

Direct Online/Offline Digital Signature Schemes.

Description: Online/offline signature schemes are useful in many situations, and two such scenarios are considered in this dissertation: bursty server authentication and embedded device authentication. In this dissertation, new techniques for online/offline signing are introduced, those are applied in a variety of ways for creating online/offline signature schemes, and five different online/offline signature schemes that are proved secure under a variety of models and assumptions are proposed. Two of the proposed five schemes have the best offline or best online performance of any currently known technique, and are particularly well-suited for the scenarios that are considered in this dissertation. To determine if the proposed schemes provide the expected practical improvements, a series of experiments were conducted comparing the proposed schemes with each other and with other state-of-the-art schemes in this area, both on a desktop class computer, and under AVR Studio, a simulation platform for an 8-bit processor that is popular for embedded systems. Under AVR Studio, the proposed SGE scheme using a typical key size for the embedded device authentication scenario, can complete the offline phase in about 24 seconds and then produce a signature (the online phase) in 15 milliseconds, which is the best offline performance of any known signature scheme that has been proven secure in the standard model. In the tests on a desktop class computer, the proposed SGS scheme, which has the best online performance and is designed for the bursty server authentication scenario, generated 469,109 signatures per second, and the Schnorr scheme (the next best scheme in terms of online performance) generated only 223,548 signatures. The experimental results demonstrate that the SGE and SGS schemes are the most efficient techniques for embedded device authentication and bursty server authentication, respectively.
Date: December 2008
Creator: Yu, Ping

Direct Strength Method for Web Crippling of Cold-formed Steel C and Z Sections Subjected to Interior One Flange Loading and End One Flange Loading

Description: The main objective of this research is to extend the “Direct strength method” for determining the web crippling strength of cold-formed steel C and Z sections subjected to End one flange loading and Interior one flange loading conditions. Direct strength method is applied for designing the columns and beams earlier. The existing specifications equation for calculating the web crippling strength of cold-formed steels designed by American Institute of Iron and Steel is very old method and it is based on the extensive experimental investigations conducted at different universities. Calculating the web crippling strength of cold-formed steels using direct strength method is a new technique. In the present research the web crippling strength of cold-formed steels were calculated using Direct Strength Method. The experimental data is collected from the tests that were conducted at different universities. The critical buckling strength of the members were calculated using Abaqus. Microsoft excel is used to generate the equations. The safety and resistance factors for the designed equations were calculated using “Load and resistance factor design” and “Allowable strength design” from North American Cold-Formed Steel Specification, 2012 edition book.
Date: December 2015
Creator: Dara, Martin Luther

Direct Strength Method for Web Crippling of Cold-formed Steel C-sections

Description: Web crippling is a form of localized buckling that occurs at points of transverse concentrated loading or supports of thin-walled structural members. The theoretical computation of web crippling strength is quite complex as it involves a large number of factors such as initial imperfections, local yielding at load application and instability of web. The existing design provision in North American specification for cold-formed steel C-sections (AISI S100, 2007) to calculate the web-crippling strength is based on the experimental investigation. The objective of this research is to extend the direct strength method to the web crippling strength of cold-formed steel C-sections. ABAQUS is used as a main tool to apply finite element analysis and is used to do the elastic buckling analysis. The work was carried out on C-sections under interior two flange (ITF) loading, end two flange (ETF) loading cases. Total of 128 (58 ITF, 70 ETF) sections were analyzed. Sections with various heights (3.5 in.to 6 in.) and various lengths (21 in. to 36 in.) were considered. Data is collected from the tests conducted in laboratory and the data from the previous researches is used, to extend the direct strength method to cold formed steel sections. Proposing a new design for both the loading cases and calculation of the resistance factors under (AISI S100, 2007) standards is done.
Date: May 2013
Creator: Seelam, Praveen Kumar Reddy