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2006

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Image-Based Nanocrystallography With Online Database Support, Peter Moeck, Ján Zahornadsky, Boris Dusek Jan 2006

Image-Based Nanocrystallography With Online Database Support, Peter Moeck, Ján Zahornadsky, Boris Dusek

Physics Faculty Publications and Presentations

The crystallographic phase and morphology of many materials change with the crystal size so that new needs arise to determine the crystallography of nanocrystals. Direct space high-resolution phase-contrast transmission electron microscopy (HRTEM) and atomic resolution scanning TEM (STEM) when combined with tools for image-based nanocrystallography in two (2D) and three (3D) dimensions possess the capacity to meet these needs. After a concise discussion of lattice-fringe visibility spheres and maps, this paper discusses lattice-fringe fingerprinting in 2D and tilt protocol applications. On-line database developments at Portland State University (PSU) that support image-based nanocrystallography are also mentioned.


Lattice Fringe Fingerprinting In Two Dimensions With Database Support, Peter Moeck, B. Seipel, R. Bjorge, P. Fraundorf Jan 2006

Lattice Fringe Fingerprinting In Two Dimensions With Database Support, Peter Moeck, B. Seipel, R. Bjorge, P. Fraundorf

Physics Faculty Publications and Presentations

A brief introduction to lattice fringe fingerprinting in two dimensions (2D) with database support is given. The method is employed for the identification of the crystal phase of a small ensemble of nanocrystals. The enhanced viability of this method in aberration-corrected transmission electron microscopes (TEMs) and scanning TEMs (STEMs) is also illustrated.


A New Color-Magnitude Diagram For Palomar 11, Matthew S. Lewis, W. M. Liu, N. E. Q. Paust, Brian Chaboyer Jan 2006

A New Color-Magnitude Diagram For Palomar 11, Matthew S. Lewis, W. M. Liu, N. E. Q. Paust, Brian Chaboyer

Dartmouth Scholarship

We present new photometry for the Galactic thick-disk globular cluster Palomar 11 extending well past the main-sequence turnoff in the V and I bands. This photometry shows noticeable, but depleted, red giant and subgiant branches. The difference in magnitude between the red horizontal branch (red clump) and the subgiant branch is used to determine that Palomar 11 has an age of 10.4 ± 0.5 Gyr. The red clump is used to derive a distance d⊙ = 14.3 ± 0.4 kpc and a mean cluster reddening of E(V - I) = 0.40 ± 0.03. There is differential …


Ubvi Ccd Photometry Of The Old Open Cluster Berkeley 17, Zosia A. C. Krusberg, Brian Chaboyer Jan 2006

Ubvi Ccd Photometry Of The Old Open Cluster Berkeley 17, Zosia A. C. Krusberg, Brian Chaboyer

Dartmouth Scholarship

Photometric UBVI CCD photometry is presented for NGC 188 and Berkeley 17. Color-magnitude diagrams (CMDs) are constructed and reach well past the main-sequence turnoff for both clusters. Cluster ages are determined by means of isochrone fitting to the cluster CMDs. These fits are constrained to agree with spectroscopic metallicity and reddening estimates. Cluster ages are determined to be 7.0 ± 0.5 Gyr for NGC 188 and 10.0 ± 1.0 Gyr for Berkeley 17, where the errors refer to uncertainties in the relative age determinations. These ages are compared to the ages of relatively metal-rich inner halo/thick-disk globular clusters and other …


Periodic Atlas Of The Metroscape: The Geography Of Water, Vivek Shandas, Alton Straub, Yongxia Kou Jan 2006

Periodic Atlas Of The Metroscape: The Geography Of Water, Vivek Shandas, Alton Straub, Yongxia Kou

Institute for Sustainable Solutions Publications and Presentations

Describes the geography of water in the Portland, Oregon metropolitan area: groundwater, rivers, irrigation, water supply, and sewer lines.


Mathematical Model Of Arsenic Adsorption In A Modified Zeolite / Microfiltration System, Miles B. Beamguard Jan 2006

Mathematical Model Of Arsenic Adsorption In A Modified Zeolite / Microfiltration System, Miles B. Beamguard

USF Tampa Graduate Theses and Dissertations

Carcinogenic health concerns over arsenic in drinking water caused the USEPA to reduce the maximum contaminant level (MCL) from 50 to 10 ppb, effective on January 23, 2006. This has forced many smaller utilities into expensive treatment or discontinuation of water distribution. Researchers throughout the world are working to develop an inexpensive method for arsenic removal to meet this MCL. Aluminum silicates, or zeolites, are naturally occurring ionic sorbents. Modification of a zeolite may enhance adsorption capacities and ion selectivity. This research investigates the arsenic adsorption capacities of a modified Chabazite. This adsorption, coupled with a hollow fiber, microfiltration membrane …


Arts In New Directions The Development And Application Of A Construct That Uses The Arts To Promote Transformation And Self-Actualization In Health Care And Education/Therapy, Alexxis Avalon Jan 2006

Arts In New Directions The Development And Application Of A Construct That Uses The Arts To Promote Transformation And Self-Actualization In Health Care And Education/Therapy, Alexxis Avalon

USF Tampa Graduate Theses and Dissertations

Artistic methods to evoke relaxation, spark creativity, and change self-perceptions are already being used by therapists, educators, and scientists. Interdisciplinary collaborations among researchers are developing to create new paradigms that incorporate the use of arts to empower individuals. By describing various connections between the arts and participants, researchers are looking at the expressive arts (including dance, music, drama, poetry, and visual arts) for transformation and self-actualization.The problem is that no construct is available to describe the transformation, "the conscious move from one deep structure of knowledge to another" (Wilber, 2004), that occurs when using the arts in health care and …


Implications Of Sleep Disorders Symptoms On School Behavior, Academics, And Quality Of Life, Erin Elizabeth Ax Jan 2006

Implications Of Sleep Disorders Symptoms On School Behavior, Academics, And Quality Of Life, Erin Elizabeth Ax

USF Tampa Graduate Theses and Dissertations

Pediatric sleep problems are among the most common yet significant pediatric health issues faced by families. Sleep problems can impact social-emotional and academic functioning of schoolchildren. Once identified, pediatric sleep problems and disorders are treatable with effective and rapid behavioral and medical interventions. The purpose of the current study was to determine the prevalence rates of symptoms of sleep disorders in a diverse school-based sample as well as the relationship between symptoms of sleep disorders and school behavior, academic achievement, and quality of life. The present study examined the relationship between the independent variables of No Sleep Disorders symptoms and …


Study Of Laplace And Related Probability Distributions And Their Applications, Gokarna Raj Aryal Jan 2006

Study Of Laplace And Related Probability Distributions And Their Applications, Gokarna Raj Aryal

USF Tampa Graduate Theses and Dissertations

The aim of the present study is to investigate a probability distribution that can be derived from the laplace probability distribution and can be used to model various real world problems. In the last few decades, there has been a growing interest in the construction of flexible parametric classes of probability distributions. Various forms of the skewed and kurtotic distributions have appeared in the literature for data analysis and modeling. In particular, various forms of the skew laplace distribution have been introduced and applied in several areas including medical science, environmental science, communications, economics, engineering and finance, among others. In …


A Case Study Of A School Implementing A Constructivist Philosophy, Joseph C. Brown Jan 2006

A Case Study Of A School Implementing A Constructivist Philosophy, Joseph C. Brown

USF Tampa Graduate Theses and Dissertations

Isaacson's (2004) dissertation chronicles the implementation of a constructivist instructional approach at Southwood Elementary School. Southwood's faculty experienced a change of principals, which the Tri-Partite Theory of Organizational Change and Succession, a theory of organizational entropy, predicts could lead to organizational entropy. This study examines the dynamics of the change in principal, as well as Isaacson's recommendation to study teachers' perceptions regarding the maintenance of the constructivist approach. This study answers three questions: 1) Are faculty still using constructivist strategies? 2) What are teacher perceptions regarding the maintenance and support of constructivist philosophy? 3) Is there congruence between what literature …


Statistical Modeling And Assessment Of Software Reliability, Louis Richard Camara Jan 2006

Statistical Modeling And Assessment Of Software Reliability, Louis Richard Camara

USF Tampa Graduate Theses and Dissertations

The present study is concerned with developing some statistical models to evaluate and analyze software reliability. We have developed the analytical structure of the logistic model to be used for testing and evaluating the reliability of a software package. The proposed model has been shown to be useful in the testing and debugging stages of the developmental process of a software package. It is important that prior to releasing a software package to marketing that we have achieved a target reliability with an acceptable degree of confidence. The proposed model has been evaluated and compared with several existing statistical models …


The Influence Of Performance Background On Instrumentalists’ Ability To Discriminate And Label Cornet And Trumpet Timbre, Gary Compton Jan 2006

The Influence Of Performance Background On Instrumentalists’ Ability To Discriminate And Label Cornet And Trumpet Timbre, Gary Compton

USF Tampa Graduate Theses and Dissertations

This study was an examination of timbre discrimination and labeling, with specific consideration of the soprano-brass timbres of cornets and trumpets. This study sought to determine whether instrumentalists differed in their ability to label and discriminate cornet and trumpet timbres, and whether these abilities were influenced by the instrumentalists' performing instrument and years of playing experience. Wind, brass and percussion players (n=100) from existing instrumental groups in the Tampa Bay area participated in the study. These groups were collegiate trumpet majors from a large public university school of music, a collegiate wind ensemble from a private university, and a brass …


A Descriptive Analysis Of The Relationship Between Specific Teacher Characteristics And Teacher Efficacy In Florida’S Low-Performing Public High Schools, Pamela S. Craig Jan 2006

A Descriptive Analysis Of The Relationship Between Specific Teacher Characteristics And Teacher Efficacy In Florida’S Low-Performing Public High Schools, Pamela S. Craig

USF Tampa Graduate Theses and Dissertations

This study was designed to collect data to determine the specific characteristics (gender, level and area of degree status, certification status, pedagogical training, gender, number of years of teaching experience, number of years teaching at the current school, and courses currently taught) of language arts teachers at Florida's low-performing pubic high schools and compare these characteristics to teachers' sense of efficacy (the extent to which teachers' believe they have the ability to bring about changes in student achievement independent of the student's background, behaviors, or motivation level). A total of 615 teachers representing 84 schools in 36 districts participated in …


Some Problems On Products Of Random Matrices, Edgardo S. Cureg Jan 2006

Some Problems On Products Of Random Matrices, Edgardo S. Cureg

USF Tampa Graduate Theses and Dissertations

We consider three problems in this dissertation, all under the unifying theme of random matrix products. The first and second problems are concerned with weak convergence in stochastic matrices and circulant matrices, respectively, and the third is concerned with the numerical calculation of the Lyapunov exponent associated with some random Fibonacci sequences. Stochastic matrices are nonnegative matrices whose row sums are all equal to 1. They are most commonly encountered as transition matrices of Markov chains. Circulant matrices, on the other hand, are matrices where each row after the first is just the previous row cyclically shifted to the right …


Parent Involvement: Differences Between African Americans And European Americans In One Florida School District, Michelle Darter-Lagos Jan 2006

Parent Involvement: Differences Between African Americans And European Americans In One Florida School District, Michelle Darter-Lagos

USF Tampa Graduate Theses and Dissertations

The purpose of this research study was to (a) analyze perceptions of parent involvement across raters (i.e., seventh grade students versus their parents) and across ethnicity (i.e., African American versus European American), and (b) examine how perceptions of parent involvement are related to academic achievement. A subsample of archival survey data collected in one central Florida school district was analyzed for the current study. Findings revealed a positive but weak relationship between students' and parents' perceptions of parent involvement regardless of ethnicity. Significant differences were found in the perceived levels of involvement by ethnicity, even when controlling for SES. In …


The Impacts Of The Handoffs On Software Development: A Cost Estimation Model, Michael Jay Douglas Jan 2006

The Impacts Of The Handoffs On Software Development: A Cost Estimation Model, Michael Jay Douglas

USF Tampa Graduate Theses and Dissertations

Effective software cost estimation is one of the most challenging and important activities in software development. The software industry does not estimate projects well. Poor estimation leads to poor project planning with resulting schedule overruns, inadequate staffing, low system quality, and many aborted projects. Research on software estimation is needed to build more accurate models of the key aspects of software development. The goals of research in this dissertation are to investigate and improve the modeling of team size and project structures in current software estimation methods.Mathematical models for estimating the impacts of project team size and three variations of …


Evaluation Of Certain Exponential Sums Of Quadratic Functions Over A Finite Field Of Odd Characteristic, Sandra D. Draper Jan 2006

Evaluation Of Certain Exponential Sums Of Quadratic Functions Over A Finite Field Of Odd Characteristic, Sandra D. Draper

USF Tampa Graduate Theses and Dissertations

Let p be an odd prime, and define f(x) as follows: f(x) as the sum from 1 to k of a_i times x raised to the power of (p to the power of (alpha_i+1)) in F_(p to the power of n)[x] where 0 is less than or equal to alpha_1 < alpha_2 < ... < alpha_k where alpha_k is equal to alpha. We consider the exponential sum S(f, n) equal to the sum_(x as x runs over the finite field with (p to the n elements) of zeta_(p to the power of Tr_n (f(x))), where zeta_p equals e to the power of (2i times pi divided by p) and Tr_n is the trace from the finite field with p to the n elements to the finite field with p elements.We provide necessary background from number theory and review the basic facts about quadratic forms over a finite field with p elements through both the multivariable and single variable approach. Our main objective is to compute S(f, n) explicitly. The sum S(f, n) is determined by two quantities: the nullity and the type of the quadratic form Tr_n (f(x)).

We give an effective algorithm for the computation of the nullity. Tables of numerical values of the nullity are included. However, the type is more subtle and more difficult to determine. Most of our investigation concerns the type. We obtain "relative formulas" for S(f, mn) in terms of S(f, n) …


Optical Imaging Of Radiolabeled Drugs In Tissue Sections Using The Microimager, Paul Dungel Jan 2006

Optical Imaging Of Radiolabeled Drugs In Tissue Sections Using The Microimager, Paul Dungel

USF Tampa Graduate Theses and Dissertations

The MicroImager is a fast, high resolution, real time, digital autoradiographic imaging tool with broad applications. This study utilizes the MicroImager to evaluate radiolabeled drug behavior in subcutaneous tissue. Experiments were conducted in conjunction with mathematical models to determine the diffusion coefficient (D) and elimination constant (k) for radiolabeled dexamethasone. Osmotic pumps containing [3H]dexamethasone were implanted into rat subcutaneous tissue over 6h, 24 h, and 60 h. Local tissue was explanted and slides were prepared for imaging. The MicroImager was then used to quantify the local concentration of 3H-dexamethasone in the tissue surrounding the tip of the osmotic pump. Betavision+ …


Vibration Level Characterization From A Needle Gun Used On U.S. Naval Vessels, Scott E. Dunn Jan 2006

Vibration Level Characterization From A Needle Gun Used On U.S. Naval Vessels, Scott E. Dunn

USF Tampa Graduate Theses and Dissertations

United States (U.S.) Navy sailors are exposed to a very large number of hazards, both chemical and physical. Occupational vibration from pneumatic air tools is one of the potential exposure hazards. There are very limited data as to the exposures to one type of tool, a needle gun or needle scaler, used by the sailors.The purpose of this study was to characterize the vibration levels generated by a needle gun used in the U.S. Navy. The design of the study evaluated the difference pressure had on the acceleration levels generated from the needle scaler. Five subjects were used in the …


Assessing The Role Of Filler Atoms In Skutterudites And Synthesis And Characterization Of New Filled Skutterudites, Grant E. Fowler Jan 2006

Assessing The Role Of Filler Atoms In Skutterudites And Synthesis And Characterization Of New Filled Skutterudites, Grant E. Fowler

USF Tampa Graduate Theses and Dissertations

For the past decade interest in skutterudites has been significant as a potentially viable material for thermoelectrics. One way to improve the effectiveness of these materials is to lower their thermal conductivity. Lattice thermal conductivity of a series of La- and Yb-filled skutterudite antimonides (with varying filling fraction) has been modeled with different phonon scattering parameters using the debye approximation. It was found that filler atoms both increase point defect scattering and resonance scattering. Subsequently, the thermal conductivity of partially-filled skutterudites AxCo4Sb12, where A = La, Eu and Yb, is analyzed using the Debye model in order to correlate the …


Analysis Of Conjugate Heat Transfer In Tube-In-Block Heat Exchangers For Some Engineering Applications, Abdullatif Abdulhadi Gari Jan 2006

Analysis Of Conjugate Heat Transfer In Tube-In-Block Heat Exchangers For Some Engineering Applications, Abdullatif Abdulhadi Gari

USF Tampa Graduate Theses and Dissertations

This project studied the effect of different parameters on the conjugate heat transfer in tube-in-block heat exchangers for various engineering applications. These included magnetic coolers (or heaters) associated with a magnetic refrigeration system, high heat flux coolers for electronic equipment, and hydronic snow melting system embedded in concrete slabs. The results of this research will help in designing the cooling/heating systems and select their appropriate geometrical dimensions and material for specific applications. Types of problems studied in this project are: steady state circular microchannels with heat source in the gadolinium substrate, transient heat transfer in circular microchannels with time varying …


Alcohol Expectancy Cognitions: Psychophysiological Perspective, Inna Fishman Jan 2006

Alcohol Expectancy Cognitions: Psychophysiological Perspective, Inna Fishman

USF Tampa Graduate Theses and Dissertations

Considerable evidence indicates that the expectations individuals hold about the effects of alcohol determine, to a degree, the amount of alcohol they drink. However, the bulk of this evidence was acquired using verbally-based measures of expectancy. The present study sought to extend the validation network by utilizing an electrophysiological measure -- the P300 component of the Event Related Potentials (ERPs) --

which is thought to index fundamental neurophysiological processes sensitive to expectancy.Previous research has demonstrated that, when presented with various outcomes of alcohol consumption, heavier drinkers endorse statements that assert positive and arousing effects of alcohol, while lighter drinkers endorse …


An Instrumental Case Study Of The Phenomenon Of Collaboration In The Process Of Improving Community College Developmental Reading And Writing Instruction, Patricia C. Gordin Jan 2006

An Instrumental Case Study Of The Phenomenon Of Collaboration In The Process Of Improving Community College Developmental Reading And Writing Instruction, Patricia C. Gordin

USF Tampa Graduate Theses and Dissertations

Focusing upon the intersections between community college faculty and assessment professionals (e.g., institutional researchers) in improving student learning outcomes, the purpose of this study was to describe, analyze, and interpret the experiences of these professionals as they planned for and conducted student learning outcomes assessment in developmental reading, writing, and study skills courses. This instrumental case study at one particular community college in Florida investigated the roles played by these individuals within the larger college effort to develop a Quality Enhancement Plan (QEP), an essential component of a regional accreditation review. The methodology included individual interviews, a focus group interview, …


An Investigation Of The Effects Of Perceived Feedback Accuracy On Performance, Ashley A. Gray Jan 2006

An Investigation Of The Effects Of Perceived Feedback Accuracy On Performance, Ashley A. Gray

USF Tampa Graduate Theses and Dissertations

This study built upon the theoretical feedback process of Ilgen, Fisher and Taylor (1979), as refined by Kinicki, Prussia, Wu, & Mckee-Ryan (2004), to contribute to a more comprehensive understanding of the mechanism underlying an individual's response to performance feedback. The feedback model implicates source credibility and the feedback-rich environment as critical elements in the process explaining recipient accuracy perceptions and responses. Thus the sign and perceived accuracy of performance feedback were investigated in a 3 x 3 (plus control) experimental design. One hundred fifty-six undergraduate students were randomly assigned to feedback conditions, in which they performed on a three-trial …


Realism, Sovereignty, And International Relations: An Examination Of Power Politics In The Age Of Globalization, Tyler Harrison Jan 2006

Realism, Sovereignty, And International Relations: An Examination Of Power Politics In The Age Of Globalization, Tyler Harrison

USF Tampa Graduate Theses and Dissertations

Many globalization theorists make the claim that the state, in its current Westphalian context, is no longer a viable unit of analysis in comparative politics or international relations. Globalists claim that in the wake of unprecedented, global integration, the state is either in retreat or on the verge of full scale extinction. In a general sense, this paper explores whether there is a sufficient amount of evidence to supports the claims of globalists that the state is dying. Moreover, the paper looks at the specific issue areas of international trade, multilateralism and the environment to determine what effects globalization has …


Development And Evaluation Of An Inertial Based Pavement Roughness Measuring System, Fengxuan Hu Jan 2006

Development And Evaluation Of An Inertial Based Pavement Roughness Measuring System, Fengxuan Hu

USF Tampa Graduate Theses and Dissertations

Roughness is an important indicator of pavement riding comfort and safety. It is a condition indicator that should be carefully considered when evaluating primary pavements. At the same time, the use of roughness measurements plays a critical role in the pavement management system.There are many devices used for roughness evaluation. The major tools used for road roughness quantify are the road profilers. In the thesis research, in order to obtain useful pavement surface condition data for pavement evaluation, an inertial based pavement roughness measuring system was developed with the combination of modern sensor technology and computer technology. The research will …


Salinity- And Temperature-Dependent Groundwater Flow In The Floridan Aquifer System Of South Florida, Joseph D. Hughes Jan 2006

Salinity- And Temperature-Dependent Groundwater Flow In The Floridan Aquifer System Of South Florida, Joseph D. Hughes

USF Tampa Graduate Theses and Dissertations

Density-dependent groundwater flow in the Floridan aquifer system (FAS) depends on chloride concentrations and fluid temperature. Previous studies addressing the role of chloride concentration and temperatures on groundwater flow in the FAS have relied on observation data or simplified two-dimensional numerical models. A three-dimensional hydrologic analysis of FAS in peninsular Florida was performed using a modified version of SUTRA (SUTRA-MS) capable of simulating multi-species solute and heat transport. SUTRA-MS was developed during this investigation and is capable of reproducing results for several problems with known solutions.The model was developed using available geometric and hydraulic parameter data and calibrated using hydraulic …


Kinematics Of Curved Flexible Beam, Saurabh Jagirdar Jan 2006

Kinematics Of Curved Flexible Beam, Saurabh Jagirdar

USF Tampa Graduate Theses and Dissertations

Compliant mechanism theory permits a procedure called rigidbody replacement, in which two or more rigid links of the mechanism are replaced by a compliant flexure with equivalent motion. Methods for designing flexure with equivalent motion to replace rigid links are detailed in Pseudo-Rigid-Body Models (PRBMs). Such models have previously been developed for planar mechanisms. This thesis develops the first PRBM for spherical mechanisms. In formulating this PRBM for a spherical mechanism, we begin by applying displacements are applied to a curved beam that cause it todeflect in a manner consistent with spherical kinematics. The motion of the beam is calculated …


A Comparability Analysis Of The National Nurse Aide Assessment Program, Peggy K. Jones Jan 2006

A Comparability Analysis Of The National Nurse Aide Assessment Program, Peggy K. Jones

USF Tampa Graduate Theses and Dissertations

When an exam is administered across dual platforms, such as paper-and-pencil and computer-based testing simultaneously, individual items may become more or less difficult in the computer version (CBT) as compared to the paper-and-pencil (P&P) version, possibly resulting in a shift in the overall difficulty of the test (Mazzeo & Harvey, 1988). Using 38,955 examinees' response data across five forms of the National Nurse Aide Assessment Program (NNAAP) administered in both the CBT and P&P mode, three methods of differential item functioning (DIF) detection were used to detect item DIF across platforms. The three methods were Mantel-Haenszel (MH), Logistic Regression (LR), …


Structured Light For Three-Dimensional Microscopy, Leo G. Krzewina Jan 2006

Structured Light For Three-Dimensional Microscopy, Leo G. Krzewina

USF Tampa Graduate Theses and Dissertations

The conventional light microscope is an indispensable tool for many physical and life science applications, but is of limited usefulness for three-dimensional imaging due to its increasingly narrow depth of field at high magnifications. Focused regions may be obscured by defocused neighbors or noise from extraneous light sources and subsurface scattering. By rejecting light originating from outside the depth of focus it is possible to minimize these problems. When a contiguous series of such focused slices, or optical sections, are obtained along an axis of an extended object they may be combined to form a complete, focused three-dimensional surface image. …