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On Prime Generation Through Primitive Divisors Of Recurrence Sequences, Richard Russell Jan 2006

On Prime Generation Through Primitive Divisors Of Recurrence Sequences, Richard Russell

Electronic Theses and Dissertations

We examine results concerning the generation of primes in certain types of integer sequences. The sequences discussed all have a connection in that each satisfies a recurrence relation. Mathematicians have speculated over many centuries that these sequences contain an infinite number of prime terms, however no proof has been given as such. We examine a less direct method of showing an infinitude of primes in each sequence by showing that the sequences contain an infinite number of terms with primitive divisors.


Meta-Raps: Parameter Setting And New Applications, Seyhun Hepdogan Jan 2006

Meta-Raps: Parameter Setting And New Applications, Seyhun Hepdogan

Electronic Theses and Dissertations

Recently meta-heuristics have become a popular solution methodology, in terms of both research and application, for solving combinatorial optimization problems. Meta-heuristic methods guide simple heuristics or priority rules designed to solve a particular problem. Meta-heuristics enhance these simple heuristics by using a higher level strategy. The advantage of using meta-heuristics over conventional optimization methods is meta-heuristics are able to find good (near optimal) solutions within a reasonable computation time. Investigating this line of research is justified because in most practical cases with medium to large scale problems, the use of meta-heuristics is necessary to be able to find a solution ...


User-Centered Virtual Environment Assessment And Design For Cognitive Rehabilitation Applications, Cali Fidopiastis Jan 2006

User-Centered Virtual Environment Assessment And Design For Cognitive Rehabilitation Applications, Cali Fidopiastis

Electronic Theses and Dissertations

Virtual environment (VE) design for cognitive rehabilitation necessitates a new methodology to ensure the validity of the resulting rehabilitation assessment. We propose that benchmarking the VE system technology utilizing a user-centered approach should precede the VE construction. Further, user performance baselines should be measured throughout testing as a control for adaptive effects that may confound the metrics chosen to evaluate the rehabilitation treatment. To support these claims we present data obtained from two modules of a user-centered head-mounted display (HMD) assessment battery, specifically resolution visual acuity and stereoacuity. Resolution visual acuity and stereoacuity assessments provide information about the image quality ...


A Non-Isolated Half Bridge Buck-Based Converter For Vrm Application And Small Signal Modeling Of A Non-Conventional Two Phase Bu, Majd Batarseh Jan 2006

A Non-Isolated Half Bridge Buck-Based Converter For Vrm Application And Small Signal Modeling Of A Non-Conventional Two Phase Bu, Majd Batarseh

Electronic Theses and Dissertations

This dissertation is about treatment of the nonbiodegradable organic content of landfill leachate by chemical oxidation combined with biological treatment. It is divided into three parts. In the first part, ferrate was compared to Fenton's reagent for the purpose of removing non-biodegradable organic compounds from mature leachate. Oxidation conditions (time, pH, and dose) were optimized to yield maximum organic removal using two leachate samples from 20 and 12-year old solid waste cells. Results from this research demonstrated that ferrate and Fenton's reagent had similar optimum pH ranges (3-5), but different organic removal capacities, ranging from 54 to 79 ...


Synchronization In Advanced Optical Communications, Inwoong Kim Jan 2006

Synchronization In Advanced Optical Communications, Inwoong Kim

Electronic Theses and Dissertations

The objective of this dissertation is to generate high power ultrashort optical pulses from an all-semiconductor mode-locked laser system. The limitations of semiconductor optical amplifier in high energy, ultrashort pulse amplification are reviewed. A method to overcome the fundamental limit of small stored energy inside semiconductor optical amplifier called "eXtreme Chirped Pulse Amplification (X-CPA)" is proposed and studied theoretically and experimentally. The key benefits of the concept of X-CPA are addressed. Based on theoretical and experimental study, an all-semiconductor mode-locked X-CPA system consisting of a mode-locked master oscillator, an optical pulse pre-stretcher, a semiconductor optical amplifier (SOA) pulse picker, an ...


Dsp Implementation Of Dc Voltage Regulation Using Adaptive Control For 200 Kw 62000 Rpm Induction Generator, Othman Elkhomri Jan 2006

Dsp Implementation Of Dc Voltage Regulation Using Adaptive Control For 200 Kw 62000 Rpm Induction Generator, Othman Elkhomri

Electronic Theses and Dissertations

The thesis discusses the development of closed loop system to control the DC voltage for 200 kW induction generator rated at a speed of 62000 RPM under different load conditions. The voltage regulation has been implemented using PI controller. A gain scheduling control algorithm has been developed to select the appropriate controller gains with respect to the generator load. Further, a relationship between the generator loads and the controller gains has been established. This relationship has been modeled using adaptive control technique to vary the gains automatically at any load condition. The adaptive control technique has been successfully generalized for ...


High Speed Turbo Tcm Ofdm For Uwb And Powerline System, Yanxia Wang Jan 2006

High Speed Turbo Tcm Ofdm For Uwb And Powerline System, Yanxia Wang

Electronic Theses and Dissertations

Turbo Trellis-Coded Modulation (TTCM) is an attractive scheme for higher data rate transmission, since it combines the impressive near Shannon limit error correcting ability of turbo codes with the high spectral efficiency property of TCM codes. We build a punctured parity-concatenated trellis codes in which a TCM code is used as the inner code and a simple parity-check code is used as the outer code. It can be constructed by simple repetition, interleavers, and TCM and functions as standard TTCM but with much lower complexity regarding real world implementation. An iterative bit MAP decoding algorithm is associated with the coding ...


Development Of Thermally Processed Nanocomposites With Controlled Surfaces, Petya Georgieva Jan 2006

Development Of Thermally Processed Nanocomposites With Controlled Surfaces, Petya Georgieva

Electronic Theses and Dissertations

The ever increasing need for technology development requires the integration of inexpensive, light weight and high strength materials which are able to meet the high standards and specifications for various engineering applications. The intention of this work is to show that the suitable material selection and the utilization of plasma spray processing can be of potential interest to a large number of industrial, biomedical and everyday life applications. This research demonstrates also that plasma processing is a promising engineering tool for multifunctional coatings and near-net-shape manufacturing. Further, the theoretical and experimental results are combined in order to explain the mechanisms ...


Modeling And Characterizations Of New Notions In Life Testing With Statistical Applications, Mohammad Sepehrifar Jan 2006

Modeling And Characterizations Of New Notions In Life Testing With Statistical Applications, Mohammad Sepehrifar

Electronic Theses and Dissertations

Knowing the class to which a life distribution belongs gives us an idea about the aging of the device or system the life distribution represents, and enables us to compare the aging properties of different systems. This research intends to establish several new nonparametric classes of life distributions defined by the concept of inactivity time of a unit with a guaranteed minimum life length. These classes play an important role in the study of reliability theory, survival analysis, maintenance policies, economics, actuarial sciences and many other applied areas.


Design And Characterization Of Noveldevices For New Generation Of Electrostaticdischarge (Esd) Protection Structures, Javier Salcedo Jan 2006

Design And Characterization Of Noveldevices For New Generation Of Electrostaticdischarge (Esd) Protection Structures, Javier Salcedo

Electronic Theses and Dissertations

The technology evolution and complexity of new circuit applications involve emerging reliability problems and even more sensitivity of integrated circuits (ICs) to electrostatic discharge (ESD)-induced damage. Regardless of the aggressive evolution in downscaling and subsequent improvement in applications' performance, ICs still should comply with minimum standards of ESD robustness in order to be commercially viable. Although the topic of ESD has received attention industry-wide, the design of robust protection structures and circuits remains challenging because ESD failure mechanisms continue to become more acute and design windows less flexible. The sensitivity of smaller devices, along with a limited understanding of ...


Analysis Of Aircraft Arrival Delay And Airport On-Time Performance, Yuqiong Bai Jan 2006

Analysis Of Aircraft Arrival Delay And Airport On-Time Performance, Yuqiong Bai

Electronic Theses and Dissertations

While existing grid environments cater to specific needs of a particular user community, we need to go beyond them and consider general-purpose large-scale distributed systems consisting of large collections of heterogeneous computers and communication systems shared by a large user population with very diverse requirements. Coordination, matchmaking, and resource allocation are among the essential functions of large-scale distributed systems. Although deterministic approaches for coordination, matchmaking, and resource allocation have been well studied, they are not suitable for large-scale distributed systems due to the large-scale, the autonomy, and the dynamics of the systems. We have to seek for nondeterministic solutions for ...


Mathematical Modeling Of Smallpox Withoptimal Intervention Policy, Niwas Lawot Jan 2006

Mathematical Modeling Of Smallpox Withoptimal Intervention Policy, Niwas Lawot

Electronic Theses and Dissertations

In this work, two differential equation models for smallpox are numerically solved to find the optimal intervention policy. In each model we look for the range of values of the parameters that give rise to the worst case scenarios. Since the scale of an epidemic is determined by the number of people infected, and eventually dead, as a result of infection, we attempt to quantify the scale of the epidemic and recommend the optimum intervention policy. In the first case study, we mimic a densely populated city with comparatively big tourist population, and heavily used mass transportation system. A mathematical ...


Heuristic 3d Reconstruction Of Irregular Spaced Lidar, Nicholas Shorter Jan 2006

Heuristic 3d Reconstruction Of Irregular Spaced Lidar, Nicholas Shorter

Electronic Theses and Dissertations

As more data sources have become abundantly available, an increased interest in 3D reconstruction has emerged in the image processing academic community. Applications for 3D reconstruction of urban and residential buildings consist of urban planning, network planning for mobile communication, tourism information systems, spatial analysis of air pollution and noise nuisance, microclimate investigations, and Geographical Information Systems (GISs). Previous, classical, 3D reconstruction algorithms solely utilized aerial photography. With the advent of LIDAR systems, current algorithms explore using captured LIDAR data as an additional feasible source of information for 3D reconstruction. Preprocessing techniques are proposed for the development of an autonomous ...


Middle School Mathematics Teacher Certification, Degree Level, And Experience, And The Effects On Teacher Attrition And Student Mathematics Achievement In A Large Urban District, Bonnie Swan Jan 2006

Middle School Mathematics Teacher Certification, Degree Level, And Experience, And The Effects On Teacher Attrition And Student Mathematics Achievement In A Large Urban District, Bonnie Swan

Electronic Theses and Dissertations

The purpose of this study was to examine the backgrounds and experiences of middle school mathematics teachers that often distinguish "quality" teachers, including certification, experience, degree type, and degree level and how those demographics and others vary for different types of schools. The emphasis was on profiling teachers in a large urban district by describing their basic features and distributions, as well as how middle school mathematics teachers, according to those differences, relate to student mathematics achievement, teacher attrition and teacher mobility. Student achievement was measured by test results from the Norm Reference Test-Normal Curve Equivalent (NRT-NCE) mathematics portion of ...


Design And Implementation Of An Emission Spectroscopy Diagnostic In A High-Pressure Strand Burner For The Study Of Solid Propell, Jason Arvanetes Jan 2006

Design And Implementation Of An Emission Spectroscopy Diagnostic In A High-Pressure Strand Burner For The Study Of Solid Propell, Jason Arvanetes

Electronic Theses and Dissertations

The application of emission spectroscopy to monitor combustion products of solid rocket propellant combustion can potentially yield valuable data about reactions occurring within the volatile environment of a strand burner. This information can be applied in the solid rocket propellant industry. The current study details the implementation of a compact spectrometer and fiber optic cable to investigate the visible emission generated from three variations of solid propellants. The grating was blazed for a wavelength range from 200 to 800 nm, and the spectrometer system provides time resolutions on the order of 1 millisecond. One propellant formula contained a fine aluminum ...


Modeling And Optimization Of Body Diode Reverse Recovery Characteristics Of Ldmos Transistors, Wesley Deschaine Jan 2006

Modeling And Optimization Of Body Diode Reverse Recovery Characteristics Of Ldmos Transistors, Wesley Deschaine

Electronic Theses and Dissertations

As switching speeds for DC-DC converter applications keep becoming faster and faster and voltage requirements become smaller and smaller, the need for new device structures becomes more prevalent. Designers of these new structures will need to make sure they take into consideration the different power losses associated with the different structures and make modifications to reduce or if possible eliminate them. A new 30V LDMOS device has been created and is being implemented into a synchronous buck converter for future DC-DC conversions. This new lateral device has a Figure of Merit of 80mÙ*nC, representing a 50% reduction from the ...


Synthesis, Processing And Characterization Of Nanocrystalline Titanium Dioxide, Shipeng Qiu Jan 2006

Synthesis, Processing And Characterization Of Nanocrystalline Titanium Dioxide, Shipeng Qiu

Electronic Theses and Dissertations

Titanium dioxide (TiO2), one of the basic ceramic materials, has found a variety of applications in industry and in our daily life. It has been shown that particle size reduction in this system, especially to nano regime, has the great potential to offer remarkable improvement in physical, mechanical, optical, biological and electrical properties. This thesis reports on the synthesis and characterization of the nanocrystalline TiO2 ceramic in details. The study selected a simple sol-gel synthesis process, which can be easily controlled and reproduced. Titanium tetraisopropoxide, isopropanol and deionized water were used as starting materials. By careful control of relative proportion ...


Decreasing Alcohol Use Among High School Students By Challenging Alcohol Expectancies, Iris Cruz Jan 2006

Decreasing Alcohol Use Among High School Students By Challenging Alcohol Expectancies, Iris Cruz

Electronic Theses and Dissertations

Altering alcohol expectancies has reduced alcohol use among college students and may lead to successful prevention of alcohol use among high school students. We randomly assigned 379 12th-grade students to an expectancy challenge, traditional alcohol information, or control condition, and used Individual Differences Scaling to map expectancies into memory network format with Preference Mapping to model likely paths of association. After expectancy and traditional alcohol interventions, higher drinking male participants exhibited a greater likelihood to associate alcohol use with negative and sedating consequences and a decreased likelihood to associate alcohol with positive and arousing consequences. Drinking decreases paralleled the magnitude ...


An Investigation Of Altruism And Personality Variables Amongbeginning Counseling Students, Laura Schmuldt Jan 2006

An Investigation Of Altruism And Personality Variables Amongbeginning Counseling Students, Laura Schmuldt

Electronic Theses and Dissertations

Altruism is loosely defined as a desire to help others as well as acts and behaviors towards that end, particularly when no expectation of personal gain or reward exists (Batson, Fultz, Schoenrade & Paduano, 1987). It seems likely that individuals who choose to pursue acareer in counseling might be doing so out of some altruistic interest; in other words a desire to come to the aid of others in distress. It has been noted as well that some individuals may enter the counseling profession based more on self-interest; for example, as "wounded healers" hoping to work on personal issues (Wheeler, 2002). Some researchers (Shapiro &Gabbard, 1996) hypothesize that overstated altruism may lead to burn-out and fatigue among some counselors whereas those who have limited altruism may have difficulties empathizing with clients. Despite the apparent relevance of altruism to counseling as a profession, very few studies have investigated the level of altruism among those in the field. The primary purpose of this study was to examine the relationship between altruism and personality variables in beginning counseling students. It is currently unclear to what extent altruism is a state (situational) vs. a trait (inherent). Grasping a greater sense of what constitutes altruistic behavior among beginning counseling students may benefit researchers in understanding the potential difficulties Shapiro & Gabbard (1996) suggest; i.e., burn-out, limited empathy or even self-gratification. The population in this study was 87 students entering a Master's ...


An Improved Microwave Radiative Transfer Model For Ocean Emissivity At Hurricane Force Surface Wind Speed, Salem El-Nimri Jan 2006

An Improved Microwave Radiative Transfer Model For Ocean Emissivity At Hurricane Force Surface Wind Speed, Salem El-Nimri

Electronic Theses and Dissertations

An electromagnetic model for predicting the microwave blackbody emission from the ocean surface under the forcing of strong surface winds in hurricanes is being developed. This ocean emissivity model will be incorporated into a larger radiative transfer model used to infer ocean surface wind speed and rain rate in hurricanes from remotely sensed radiometric brightness temperature. The model development is based on measurements obtained with the Stepped Frequency Microwave Radiometer (SFMR), which routinely flys on the National Oceanic and Atmospheric Administration's hurricane hunter aircraft. This thesis presents the methods used in the wind speed model development and validation results ...


Articulation And Phonological Systems Of Spanish-English Speaking Florida 4 And 5 Year Olds, Jennifer Dennis Jan 2006

Articulation And Phonological Systems Of Spanish-English Speaking Florida 4 And 5 Year Olds, Jennifer Dennis

Electronic Theses and Dissertations

There are currently five million children three to five years of age (i.e., 59.5% of all children from three to five), who are bilingual, living in the United States. By 2025, Census data show that the population of Florida will increase by some 26 percent adding another 5.5 million people to the state. There are a limited amount of studies yielding data on the development of Spanish phonology in 4 and 5 year old children residing in the United States, particularly in Florida. Consequently, there is limited normative information pertaining to articulation and phonological development in Spanish ...


Near-Infrared Observations Of Comet-Asteroid Transition Objects, Julie Elaine Ziffer Jan 2006

Near-Infrared Observations Of Comet-Asteroid Transition Objects, Julie Elaine Ziffer

Electronic Theses and Dissertations

The primary objective of this research is to characterize the surface composition of five comet-asteroid transition objects via near-infrared spectroscopy. The five targets include two asteroids with Tisserand invariants lower than 3.0 (1373 Cincinnati and 2906 Caltech), one asteroid that is likely an extinct comet (944 Hidalgo), one intermittent activity comet (162P/Siding Spring), and one nearly dormant comet (28P/Neujmin1). Previous research regarding cometary end states and dynamical and physical properties of comets and asteroids provides the foundation for this work. Focusing primarily on the 1-2.5 µm spectral region of the five target objects, this project specifically ...


Computer-Based Instructional Systems Design Tools: Current State And Implications For The Future, Anna A. Andrews Jan 2006

Computer-Based Instructional Systems Design Tools: Current State And Implications For The Future, Anna A. Andrews

Electronic Theses and Dissertations

This study examines the current state of computer-based instructional systems design (ISD) tools and outlines its implications for the future. The study utilizes the grounded theory methodology to capture and document modern instructional designers' perspectives regarding the current state of ISD tools, the issues associated with them, and their interrelationships. The study also presents a framework for classifying modern ISD tools and a conceptual prototype of a designer-oriented system of computer-based ISD tools.


Digital Controller Implementation For Disturbance Rejection In The Optical Coupling Of A Mobile Experimental Laser Tracking Systems, Matthew Rhodes Jan 2006

Digital Controller Implementation For Disturbance Rejection In The Optical Coupling Of A Mobile Experimental Laser Tracking Systems, Matthew Rhodes

Electronic Theses and Dissertations

Laser tracking systems are an important aspect of the NASA space program, in particular for conducting research in relation to satellites and space port launch vehicles. Often, launches are conducted at remote sites which require all of the test equipment, including the laser tracking systems, to be portable. Portable systems are more susceptible to environmental disturbances which affect the overall tracking resolution, and consequently, the resolution of any other experimental data being collected at any given time. This research characterizes the optical coupling between two systems in a Mobile Experimental Laser Tracking system and evaluates several control solutions to minimize ...


Individual Preferences In The Use Of Automation, Jennifer Thropp Jan 2006

Individual Preferences In The Use Of Automation, Jennifer Thropp

Electronic Theses and Dissertations

As system automation increases and evolves, the intervention of the supervising operator becomes ever less frequent but ever more crucial. The adaptive automation approach is one in which control of tasks dynamically shifts between humans and machines, being an alternative to traditional static allocation in which task control is assigned during system design and subsequently remains unchanged during operations. It is proposed that adaptive allocation should adjust to the individual operators' characteristics in order to improve performance, avoid errors, and enhance safety. The roles of three individual difference variables relevant to adaptive automation are described: attentional control, desirability of control ...


Silence, Absence, And Mystery In Linda Hogan's Mean Spirit, Solar Storms, And Power, Kathryn Erickson Jan 2006

Silence, Absence, And Mystery In Linda Hogan's Mean Spirit, Solar Storms, And Power, Kathryn Erickson

Electronic Theses and Dissertations

In Mean Spirit, Solar Storms, and Power, Linda Hogan uses the devices of silence, absence, and mystery to articulate the oppression and marginalization of Native Americans. Specifically, because of the environmental crises that produce conflict in each novel, the project benefits from ecocriticism, ecofeminism, and ecopsychology. Also, because of various interpretations that open up when silence is examined, theories of deconstruction strengthen the thesis. Ultimately, Hogan's characters move from silence as a form of tyranny to silence as a form of reconnection with tribal ways. As the characters discover pathways to native traditions, they also discover spiritual connections with ...


Characterization And Evaluation Of The Immunogenizity Of Chloroplast-Derived 19-Kilodalton C-Terminal Merozoite Surface Antigen 1 (Msp1) Of Plasmodium Yoelii Yoelii, Sushamadevi Kamarajugadda Jan 2006

Characterization And Evaluation Of The Immunogenizity Of Chloroplast-Derived 19-Kilodalton C-Terminal Merozoite Surface Antigen 1 (Msp1) Of Plasmodium Yoelii Yoelii, Sushamadevi Kamarajugadda

Electronic Theses and Dissertations

Malaria is a protozoan disease caused in humans by four different species of the genus Plasmodium (P. falciparum, P. vivax, P. ovale, P. malarie) and in rodents by Plasmodium yoelii yoelii. It has been reported that 1.5 to 3 million deaths occur worldwide due to malaria and the DALY (Daily affected life years) reports about 0.76% of world population affected by the disease in some of the major countries like Africa, Asia, Latin America etc., Due to the development of resistance to drugs by the parasite, there is an urgent need and prime importance for the development of ...


Expression Of Heterologous Proteins In Transgenic Tobacco Chloroplasts To Produce A Biopharmaceutical And Biopolymer, Andrew Leon Devine Jan 2006

Expression Of Heterologous Proteins In Transgenic Tobacco Chloroplasts To Produce A Biopharmaceutical And Biopolymer, Andrew Leon Devine

Electronic Theses and Dissertations

The chloroplast has been demonstrated to be an ideal compartment to accumulate certain proteins or their biosynthetic products that would be harmful if they were accumulated in the cytoplasm. Hyper-expression of foreign proteins in chloroplast transgenics has accumulated up to 46% total soluble protein, this is possible due to the ~100 chloroplast genomes per chloroplast and ~100 chloroplasts per cell which can therefore, contain up to 10,000 copies of the transgene. Maternal gene inheritance of plastids in most crop plants results in natural gene containment. Chloroplast transformation also eliminates positional effects that are frequently observed with nuclear transformation and ...


Bioinformatic Analysis Of Solanaceae Chloroplast Genomes And Characterization Of An Arabidopsis Protein Disulfide Isomerase In Transgenic Tobacco Chloroplasts, Justin James Grevich Jan 2006

Bioinformatic Analysis Of Solanaceae Chloroplast Genomes And Characterization Of An Arabidopsis Protein Disulfide Isomerase In Transgenic Tobacco Chloroplasts, Justin James Grevich

Electronic Theses and Dissertations

Throughout history, traditional plant breeding has been used to provide resistance to pests, disease and other forms of environmental stress, as well as to increase yield and improve upon quality and processing attributes. Over the last decade, the advancement in sequencing technology and bioinformatic analysis has unleashed a wealth of knowledge about chloroplast genetic organization and evolution. The lack of complete plastid genome sequences is one of the major limitations in advancing plastid genetic engineering to other useful crops. This is due to the fact that plastid genome sequences are essential for the identification of endogenous regulatory sequences and optimal ...


Studies On The Novel Function Of Amyloid Precursor Protein In Glial Differentiation Of Neural Stem Cells, Young-Don Kwak Jan 2006

Studies On The Novel Function Of Amyloid Precursor Protein In Glial Differentiation Of Neural Stem Cells, Young-Don Kwak

Electronic Theses and Dissertations

Although amyloid β (Aβ) deposition has been a hallmark of Alzheimer’s disease (AD), the physiological function of amyloid precursor protein (APP) is not clear. Our results suggested that high concentration of APP induces glial differentiation while physiological level of APP promotes migration and differentiation of neural stem cell (HNSC). HNSCs were mainly differentiated into astrocytes when they are transplanted into APP transgenic mouse brain or treated with a high concentration of secreted-type APP (sAPP) in culture. Staurosporine (STS) induced a distinctive astrocytic morphology in NT-2/D1 neural progenitor cells with expressions of APP and astrocyte-specific markers, glial fibrillary acidic ...