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America COMPETES Reauthorization Act of 2010 (H.R. 5116) and the America COMPETES Act (P.L. 110-69): Selected Policy Issues

Description: This report provides background information on P.L. 110-69 and H.R. 5116 and analyzes four policy issues addressed by both measures: (1) STEM Education, (2) Federal Research Programs and Activities, (3) Broadening Participation, and (4) Funding. It also discusses selected policy concerns identified in the debate about U.S. competitiveness and describes how H.R. 5116 responds to those concerns. It contains a description of federal multi-agency research and development initiatives that are included in H.R. 5116.
Date: May 18, 2010
Creator: Gonzalez, Heather B.; Sargent, John F., Jr. & Moloney Figliola, Patricia
Partner: UNT Libraries Government Documents Department

Analyzing Tradeoffs between Privacy Concerns and Active Social Media Presence of 18- to 30-Year-Old College Students

Description: This study applied the impression management theory in the context of social networking to investigate the generalized research question of this dissertation which is "Do active social media presence and various privacy concerns influence online behaviors of students on social media?" The results and conclusions are presented via the conduct of three different studies and the summary provides insights and explain the overall contribution of the research. For each study we developed a research model for which data was collected separately for each of these models. Hypotheses of each model were tested by partial least squares- structural equation modeling techniques using SmartPLS 2.0. Our findings confirm the hypotheses and showed that all the predictors positively influence online social networking behaviors. Active social media presence is operationalized as predictors such as SNS stalking awareness, Selective disclosure, desired differential persona, impression motivation, and information trustworthiness. Privacy concerns have been operationalized as SNS privacy awareness, technology awareness. Online behaviors have been operationalized as responsible image and reckless image.
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: August 2018
Creator: Gadgil, Guruprasad Yashwant
Partner: UNT Libraries

Customers' Attitudes toward Mobile Banking Applications in Saudi Arabia

Description: Mobile banking services have changed the design and delivery of financial services and the whole banking sector. Financial service companies employ mobile banking applications as new alternative channels to increase customers' convenience and to reduce costs and maintain profitability. The primary focus of this study was to explore the Saudi bank customers' perceptions about the adoption of mobile banking applications and to test the relationships between the factors that influence mobile banking adoption as independent variables and the action to adopt them as the dependent variable. Saudi customers' perceptions were tested based on the extended versions of IDT, TAM and other diffusion of innovation theories and frameworks to generate a model of constructs that can be used to study the use and the adoption of mobile technology by users. Koenig-Lewis, Palmer, & Moll's (2010) model was used to test its constructs of (1) perceived usefulness, (2) perceived ease of use, (3) perceived compatibility, (4) perceived credibility, (5) perceived trust, (6) perceived risk, and (7) perceived cost, and these were the independent variables in current study. This study revealed a high level of adoption that 82.7% of Saudis had adopted mobile banking applications. Also, the findings of this study identified a statistically significant relationship between all of demographic differences: gender, education level, monthly income, and profession and mobile banking services among adopters and non-adopters. Seven attributes relating to the adoption of mobile banking applications were evaluated in this study to assess which variables affected Saudi banks customers in their adoption of mobile banking services. The findings indicated that the attributes that significantly affected the adoption of mobile banking applications among Saudis were perceived trust, perceived cost, and perceived risk. These three predictors, as a result, explained more than 60% of variance in intention to adopt mobile banking technology in Saudi Arabia. ...
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: August 2016
Creator: Alshara, Mohammed Ali
Partner: UNT Libraries

The DHS S&T Directorate: Selected Issues for Congress

Description: This report provides a brief overview of the Science and Technology (S&T) Directorate's mission, organization, and budgetary structure; a discussion of selected critiques of the S&T Directorate; and an analysis of selected issues facing congressional policymakers.
Date: September 17, 2013
Creator: Shea, Dana A.
Partner: UNT Libraries Government Documents Department

A Study of Selected Factors Related to Permanency in Science Teaching

Description: The purpose of this study is to gather information related to some factors which are considered to be characteristic of science teaching; to attempt to identify some elements of permanency in science teaching; and to analyze some relationships between the results of the above two criteria with the view of establishing some factors which may be useful as predictors of permanency, or indicative of patterns of permanency, in science teaching.
Date: August 1958
Creator: Lovelace, Allen J.
Partner: UNT Libraries

The President's Office of Science and Technology Policy (OSTP): Issues for Congress

Description: This report provides an overview of the history of science and technology (S&T) advice to the President and discusses selected issues and options for Congress regarding the Office of Science and Technology Policy (OSTP) Director, OSTP management and operations, the President's Council of Advisors on Science and Technology (PCAST), and the National Science and Technology Council (NSTC).
Date: January 13, 2014
Creator: Sargent, John F., Jr. & Shea, Dana A.
Partner: UNT Libraries Government Documents Department

Science and Pseudo-Science in Poe's Works

Description: This study attempts to list subjects in the field of Science, in which Poe had an interest. For the purpose of this study, the writer has divided the field of Science into the following heads: medicine, chemistry, biology, navigation, metrology, astronomy, physics, mathematics, and invention. Pseudo-sciences classified as: psychology, metphysics, phrenolgy, astrology, galvanism, mesmerism, logic reasoning, cryptography, and graphology.
Date: August 1938
Creator: Hall, Thomas
Partner: UNT Libraries

America COMPETES Acts: FY2008-FY2013 Funding Tables

Description: This report discusses major provisions of the America COMPETES Reauthorization Act of 2010 that are set to expire in 2013. This report has been updated to reflect FY2013 enacted funding levels--as contained in P.L. 113- 6 (Consolidated and Further Continuing Appropriations Act, 2013)--for specified COMPETES related accounts.
Date: April 15, 2013
Creator: Gonzalez, Heather B.
Partner: UNT Libraries Government Documents Department

The DHS S&T Directorate: Selected Issues for Congress

Description: This report provides a brief overview of the Science and Technology (S&T) Directorate's mission, organization, and budgetary structure; a discussion of selected critiques of the S&T Directorate; and an analysis of selected issues facing congressional policymakers.
Date: April 14, 2014
Creator: Shea, Dana A.
Partner: UNT Libraries Government Documents Department

High Temperature coatings based on {beta}-NiAI

Description: High temperature alloys are reviewed, focusing on current superalloys and their coatings. The synthesis, characerization, and oxidation performance of a NiAl–TiB{sub 2} composite are explained. A novel coating process for Mo–Ni–Al alloys for improved oxidation performance is examined. The cyclic oxidation performance of coated and uncoated Mo–Ni–Al alloys is discussed.
Date: July 10, 2012
Creator: Severs, Kevin
Partner: UNT Libraries Government Documents Department

Hot electron dynamics in graphene

Description: Graphene, a two-dimensional (2D) honeycomb structure allotrope of carbon atoms, has a long history since the invention of the pencil [Petroski (1989)] and the linear dispersion band structure proposed by Wallace [Wal]; however, only after Novoselov et al. successively isolated graphene from graphite [Novoselov et al. (2004)], it has been studied intensively during the recent years. It draws so much attentions not only because of its potential application in future electronic devices but also because of its fundamental properties: its quasiparticles are governed by the two-dimensional Dirac equation, and exhibit a variety of phenomena such as the anomalous integer quantum Hall effect (IQHE) [Novoselov et al. (2005)] measured experimentally, a minimal conductivity at vanishing carrier concentration [Neto et al. (2009)], Kondo effect with magnetic element doping [Hentschel and Guinea (2007)], Klein tunneling in p-n junctions [Cheianov and Fal’ko (2006), Beenakker (2008)], Zitterbewegung [Katsnelson (2006)], and Schwinger pair production [Schwinger (1951); Dora and Moessner (2010)]. Although both electron-phonon coupling and photoconductivity in graphene also draws great attention [Yan et al. (2007); Satou et al. (2008); Hwang and Sarma (2008); Vasko and Ryzhii (2008); Mishchenko (2009)], the nonequilibrium behavior based on the combination of electronphonon coupling and Schwinger pair production is an intrinsic graphene property that has not been investigated. Our motivation for studying clean graphene at low temperature is based on the following effect: for a fixed electric field, below a sufficiently low temperature linear eletric transport breaks down and nonlinear transport dominates. The criteria of the strength of this field [Fritz et al. (2008)] is eE = T2/~vF (1.1) For T >√eE~vF the system is in linear transport regime while for T <√eE~vF the system is in nonlinear transport regime. From the scaling’s point of view, at the nonlinear transport regime the temperature T and electric field E are also ...
Date: October 20, 2011
Creator: Ling, Meng-Cheieh
Partner: UNT Libraries Government Documents Department

Ag on Si(111) from basic science to application

Description: In our work we revisit Ag and Au adsorbates on Si(111)-7x7, as well as experiment with a ternary system of Pentacene, Ag and Si(111). Of particular interest to us is the Si(111)-({radical}3x{radical}3)R30{degree}–Ag (Ag-Si-{radical}3 hereafter). In this thesis I systematically e plore effects of Ag deposition on the Ag-Si-{radical}3 at different temperatures, film thicknesses and deposition fluxes. The generated insight of the Ag system on the Si(111) is then applied to generate novel methods of nanostructuring and nanowire growth. I then extend our expertise to the Au system on the Ag-Si(111) to gain insight into Au-Si eutectic silicide formation. Finally we explore behavior and growth modes of an organic molecule on the Ag-Si interface.
Date: April 4, 2012
Creator: Belianinov, Aleksey
Partner: UNT Libraries Government Documents Department

Al-Ca and Al-Fe metal-metal composite strength, conductivity, and microstructure relationships

Description: Deformation processed metal-metal composites (DMMC’s) are composites formed by mechanical working (i.e., rolling, swaging, or wire drawing) of two-phase, ductile metal mixtures. Since both the matrix and reinforcing phase are ductile metals, the composites can be heavily deformed to reduce the thickness and spacing of the two phases. Recent studies have shown that heavily drawn DMMCs can achieve anomalously high strength and outstanding combinations of strength and conductivity. In this study, Al-Fe wire composite with 0.07, 0.1, and 0.2 volume fractions of Fe filaments and Al-Ca wire composite with 0.03, 0.06, and 0.09 volume fractions of Ca filaments were produced in situ, and their mechanical properties were measured as a function of deformation true strain. The Al-Fe composites displayed limited deformation of the Fe phase even at high true strains, resulting in little strengthening effect in those composites. Al-9vol%Ca wire was deformed to a deformation true strain of 13.76. The resulting Ca second-phase filaments were deformed to thicknesses on the order of one micrometer. The ultimate tensile strength increased exponentially with increasing deformation true strain, reaching a value of 197 MPa at a true strain of 13.76. This value is 2.5 times higher than the value predicted by the rule of mixtures. A quantitative relationship between UTS and deformation true strain was determined. X-ray diffraction data on transformation of Al + Ca microstructures to Al + various Al-Ca intermetallic compounds were obtained at the Advanced Photon Source at Argonne National Laboratory. Electrical conductivity was measured over a range of true strains and post-deformation heat treatment schedules.
Date: December 1, 2011
Creator: Kim, Hyong June
Partner: UNT Libraries Government Documents Department

Microstructure study of the rare-earth intermetallic compounds R5(SixGe1-x)4 and R5(SixGe1-x)3

Description: The unique combination of magnetic properties and structural transitions exhibited by many members of the R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} family (R = rare earths, 0 ≤ x ≤ 1) presents numerous opportunities for these materials in advanced energy transformation applications. Past research has proven that the crystal structure and magnetic ordering of the R{sub 5(Si{sub x}Ge{sub 1-x}){sub 4} compounds can be altered by temperature, magnetic field, pressure and the Si/Ge ratio. Results of this thesis study on the crystal structure of the Er{sub 5}Si{sub 4} compound have for the first time shown that the application of mechanical forces (i.e. shear stress introduced during the mechanical grinding) can also result in a structural transition from Gd{sub 5}Si{sub 4}-type orthorhombic to Gd{sub 5}Si{sub 2}Ge{sub 2}-type monoclinic. This structural transition is reversible, moving in the opposite direction when the material is subjected to low-temperature annealing at 500 ˚C. Successful future utilization of the R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} family in novel devices depends on a fundamental understanding of the structure-property interplay on the nanoscale level, which makes a complete understanding of the microstructure of this family especially important. Past scanning electron microscopy (SEM) observation has shown that nanometer-thin plates exist in every R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} (“5:4”) phase studied, independent of initial parent crystal structure and composition. A comprehensive electron microscopy study including SEM, energy dispersive spectroscopy (EDS), selected area diffraction (SAD), and high resolution transmission electron microscopy (HRTEM) of a selected complex 5:4 compound based on Er rather than Gd, (Er{sub 0.9Lu{sub 0.1}){sub 5}Si{sub 4}, has produced data supporting the assumption that all the platelet-like features present in the R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} family are hexagonal R{sub 5}(Si{sub x}Ge{sub 1-x}){sub 3} (“5:3”) phase and possess the same reported orientation relationship that exists for the Gd{sub 5}Ge{sub 4} and Gd{sub ...
Date: July 26, 2012
Creator: Cao, Qing
Partner: UNT Libraries Government Documents Department

Laser Processing of Metals and Polymers

Description: A laser offers a unique set of opportunities for precise delivery of high quality coherent energy. This energy can be tailored to alter the properties of material allowing a very flexible adjustment of the interaction that can lead to melting, vaporization, or just surface modification. Nowadays laser systems can be found in nearly all branches of research and industry for numerous applications. Sufficient evidence exists in the literature to suggest that further advancements in the field of laser material processing will rely significantly on the development of new process schemes. As a result they can be applied in various applications starting from fundamental research on systems, materials and processes performed on a scientific and technical basis for the industrial needs. The interaction of intense laser radiation with solid surfaces has extensively been studied for many years, in part, for development of possible applications. In this thesis, I present several applications of laser processing of metals and polymers including polishing niobium surface, producing a superconducting phase niobium nitride and depositing thin films of niobium nitride and organic material (cyclic olefin copolymer). The treated materials were examined by scanning electron microscopy (SEM), electron probe microanalysis (EPMA), atomic force microscopy (AFM), high resolution optical microscopy, surface profilometry, Fourier transform infrared spectroscopy (FTIR) and x-ray diffraction (XRD). Power spectral density (PSD) spectra computed from AFM data gives further insight into the effect of laser melting on the topography of the treated niobium.
Date: May 31, 2012
Creator: Singaravelu, Senthilraja
Partner: UNT Libraries Government Documents Department