Digital Commons Network^™

Well Characteristics Influencing Microscopic Particulate Analysis Risk Index, Robert Christopher Sharek

Retrospective Theses and Dissertations

Cryptosporidium parvum is a common surface water contaminant that can cause illness in human beings. The presence of this etiological agent in groundwater identifies the groundwater as under the direct influence (GWUDI) of surface water. Currently the determination of GWUDI water sources requires an expensive, labor-intensive laboratory procedure called the Microscopic Particulate Analysis (MPA). The results of the MPA provide a risk index that rates the degree of surface water contamination. The objective of this study is to identify other methods of identifying GWUDI of surface waters, such as well characteristics and hydrogeologic factors which may contribute to higher MPA …

Numerical, Image, And Signal Processing Algorithms Applied To Radar Rainfall Estimation, John Eugene Lane

Retrospective Theses and Dissertations

Since the advent of radar in the 1940s, it has been well known that water drops composing precipitation scatter microwaves in a predictable manner. This characteristic of early. radar has lead to the present day Weather Surveillance Radar (WSR-88D) or NEXRAD systems, operated by the National Weather Service (NWS). In parallel to the evolution of weather radar for measuring precipitation over large areas, remote networks of rain gauges have been deployed and managed by agencies such as the Florida Water Management Districts. Since the recent deployment of the NWS network of WSR-88D, as well as the recent launch of the …

Nonlinear Modeling Of Concrete-Filled Frp Tubes Using The Finite Element Method, Kenneth T. Zagers

Retrospective Theses and Dissertations

Fiber reinforced plastic (FRP) has in recent years emerged as an alternative reinforcement for structural concrete. The properties that make FRP appealing to the construction industry include its resistance to electro-chemical corrosion, high strength-to-weight ratio, and electrical insulation. An efficient use of FRP is in the form of concrete-filled tubes, where the tube not only protects the concrete against environmental factors, but also provides confinement and external reinforcement. Since use of fiber composites for confining concrete is relatively new, analytical work in this area is limited to the models that were originally developed for transverse steel reinforcement. However, it has …

Nineteenth-Century American Housekeeping Books : Women's Workplace Manuals Historical Research In Technical Writing, Melanie C. Woods

Retrospective Theses and Dissertations

This thesis analyzes three American housekeeping books—Lydia Maria Child's The American Frugal Housewife, Catherine Beecher and Harriet Beecher Stowe's The American Woman's Home, and Helen Campbell Stuart's The Easiest Way in Housekeeping and Cooking—as historical examples of technical writing. The study follows current recommendations for historical research in the field, namely, to analyze technical writing texts in consideration of their historical context. This involves determining what constituted technical writing in the nineteenth century; considering the publishing context of the study; and applying this definition to analyze three housekeeping books as technical manuals. These texts exemplify technical writing …

Parent Childrearing Beliefs And Child Externalizing Behaviors In Families Of Adhd And Odd Children, June E. Hoefling

Retrospective Theses and Dissertations

This study investigated the relationship between the perceived externalizing behaviors of children with attention-deficit/hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) and the maladaptive childrearing beliefs of their parents. The study used archival survey data provided by Intervention Services, Inc., a community mental health center. Data from 338 families with a child diagnosed with ADHD or ODD were analyzed. The study used the Conners' Parent Behavior Rating Scale short version to measure the level of conduct problems, impulsivity, and hyperactivity of the children as perceived by the parents. The Adult-Adolescent Parenting Inventory was used to measure the degree of parental …

Campus Safety Directors: A Leadership Frame Analysis, Ross A. Wolf

Retrospective Theses and Dissertations

This study is based on leadership frame theory as developed by Drs. Lee Bolman and Terrence Deal who merged several different schools of theory into four different frames: structural, human resource, political, and symbolic. In July, 1998 the Leadership Orientation (Self) survey, developed by Bolman and Deal (1990a) was distributed to 343 campus safety directors at American public four-year postsecondary institutions. A return of 190 (55.4%) useable survey instruments was obtained in this study.

The utilization of leadership frames by campus safety directors was examined as well as the relationship between frame usage and age, education level, length of time …

Florida Social Studies Leaders' Perceptions Regarding An Afrocentric Curriculum, Vicki Kaplan Banks

Retrospective Theses and Dissertations

The purpose of this research study was to gain insight into the perceptions Florida's leaders have regarding the inclusion of an Afrocentric curriculum. The leaders chosen for this study were the Florida Council for the Social Studies Board and the Association of Social Studies Supervisors. These leaders were sent a questionnaire that contained 57 statements about social studies curriculum content in a Likert scale format. The results of the survey were reported by using mean scores and frequency distributions.

The Likert survey statements examined respondents' viewpoints with regard to diversity, Afrocentrism, and Eurocentrism. The results of the survey were used …

Composition And Change Of Maritime Hammock Flora In East-Central Florida After 20 Years, Donald John Spence

Retrospective Theses and Dissertations

The vegetation of eight east-central Florida maritime hammocks studied in 1997 were compared to similar data collected over 20 years ago. Study sites are located in the northern half of the Indian River Lagoon system mostly within Canaveral National Seashore and Merritt Island National Wildlife Refuge. The upland hammock vegetation throughout the state generally has an oak-palm association, but here these species dominate. Results show that sabal palm, live oak, laurel oak, and pignut hickory, the four dominant tree species in 1976-77, are still dominant in 1997; however, there has been a loss in tree species richness. Most shrub species …

Development And Saw Device Implementation Of A New Weighted Stepped Chirp Code Signal For Direct Sequence Spread Spectrum Communications Systems, Scott Edward Carter

Retrospective Theses and Dissertations

This work introduces the new weighted stepped chirp code signal for direct sequence spread spectrum (DS/SS) communications systems. This code signal uses the truncated cosine series functions as the chip functions. This code signal is the result of discretizing a continuous wave (CW) chirp which results in enhanced performance versus a pseudonoise (PN) code and equivalent performance and easier implementation than a CW chirp. This code signal will be shown to possess improved compression ratio (CR), peak sidelobe level (PSL), integrated sidelobe level (ISL), and bit error rate (BER) when compared to a PN code of identical code length and …

Laser Welding Of Sheet Metals, Jian Xie

Retrospective Theses and Dissertations

Laser welding of sheet metals is an important application of high power lasers, and has many advantages over conventional welding techniques. Laser welding has a great potential to replace other welding technique in the car-body manufacturing because of high laser weld quality and relatively low manufacturing cost associated with the laser technique. However, a few problems related to the laser welding of sheet metals limit its applications in industries. To have a better understanding of the welding process, laser welding experimental studies and theoretical analysis are necessary.

Temperature-dependent absorptivities of various metals are obtained theoretically for CO2, COIL (Chemical Oxygen-Iodine …

Telecourse And Traditional Computer Applications : Exploring The Impact Of Review Sessions, Carol Odette Bourke

Retrospective Theses and Dissertations

The purpose of the study was to explore the effects of review sessions on student achievement and retention in a computer applications course taught by televised distance learning and traditional instruction. Identified within the study were method of instruction, review, and grades in televised and traditional computer applications courses. A quasi-experimental design was used to measure the effects of review sessions on student achievement and retention in computer applications classes. Intact classes were used to form the 4 groups used in this study. Randomization was limited to choices students made in registering for the classes. The control groups for this …

The Effect Of Varying Temperature, Flux And Pretreatment On The Microfiltration Of Lake Michigan Water, Karen Linda Kopp

Retrospective Theses and Dissertations

This study investigated microfiltration of Lake Michigan Water for the production of drinking water. A 60 gpm Memcor microfiltration pilot plant was operated for nine months at Manitowoc, Wisconsin to determine and model the performance characteristics of a microfiltration pilot plant for varying surface water conditions. Statistical regression and modeling was used to determine and develop quantitative relationships between time of operation and several operational variables for water quality and productivity. Modifications of Darcy's Law and flux decline data were used to develop a model relating temperature and flux to cleaning frequency. Statistical hypothesis testing and associated modeling were used …

Fatigue : Investigation Of A Human Factor For Aviation Curricula, Thomas R. Weitzel

Retrospective Theses and Dissertations

This descriptive study investigated the perceived problem of human fatigue as an operational consideration within the U.S. air carrier industry and the status of fatigue as content within U.S. aviation education/training curricula. An instrument was developed and expert-validated for self-completion by the following three groups (each with its sample size): (a) aviation higher education, represented by a mailing to 50 individuals; (b) air carrier training/management, represented by a mailing to 50 individuals; and (c) a professional training group of 58 general aviation flight instructors, with administration by the researcher during scheduled company meetings. The resultant SPSS data set consisted of …

The Incident At The Colonel's, Jason G. Clark

Retrospective Theses and Dissertations

No abstract provided.

Bat House Use In Central Florida, With Emphasis On Nycticeius Humeralis And Tadarida Brasiliensis Cynocephala, Laura Seckbach Finn

Retrospective Theses and Dissertations

Bat houses and roost sites utilized by Tadarida brasiliensis and Nycticeius humeralis were studied in four central Florida counties. Temperatures were monitored in occupied roosts and in bat houses. It was determined that the presence of bats affects roost temperature. The mean temperature in the bat house that was preferred at the Seminole Community College (SCC) site was above ambient temperature a significantly greater amount of time than mean temperature in the other style houses located at that site. A colony of bats roosting in buildings on the property of SCC was successfully relocated into bat houses located .4 kilometers …

The Effect Of Water Immersion On Lactic Acid Kinetics During Swimming Interval Training Recovery Periods, Richard P. Morris

Retrospective Theses and Dissertations

The purpose of the study was to determine the difference in the circulation of lactic acid following high intensity swimming, between resting immersed in water or resting sitting on the pool deck, completely out of the water. Six (four male and two female) collegiate swimmers volunteered for the study. The swimmers were randomly assigned to two groups and a counterbalance design was employed, where each group experienced both treatments (one resting out of the water, one resting in the water), in different orders. Each swimmer completed an identical warm-up and then swam five 100 yard swims at 85-95% intensity, with …

Spectral And Temporal Response Of Optical Nonlinearities, Arthur Dogariu

Retrospective Theses and Dissertations

This dissertation reports a series of experiments directed towards nonlinear material characterization. A series of organic molecules, semiconductors, liquid crystals and inorganic clusters are investigated with Z-Scan and excite-probe measurements in order to determine the magnitude and dynamics of their nonlinear absorption and refraction. Much of this work is motivated by our search for a better optical limiter. The nonlinear absorption mechanism leading to optical limiting is investigated and its physical parameters are determined. The reverse saturable absorption (RSA) spectrum of several organic dyes is obtained in the visible in a single measurement by using an ultrafast nonlinear spectrometer. This …

The Effects Of Humor On Secretory Immunoglobulin A In Aids Patients And Non-Immunodeficients, Howard Scott Mcgregor

Retrospective Theses and Dissertations

The primary purpose of this study was to evaluate 'sense of humor' and a humorous external event as possible factors effecting functioning levels of the immune system for immunodeficient and non-immunodeficient populations. Specifically, it was to investigate the degree in which a humorous video effected levels of secretory immunoglobulin A (SIgA) in AIDS patients and non-immunodeficient students. It was hypothesized that all subjects would show an increased level of SIgA after exposure to the humorous video. A greater immune response was expected from the non-immunodeficient group. However, a significant increased level of SIgA was still expected in the AIDS patients …

Prediction Of Simulator Sickness In A Virtual Environment, Eugenia M. Kolasinski

Retrospective Theses and Dissertations

Sickness induced by Virtual Reality (VR) devices poses a genuine threat to the viability of this new technology and its potential products. If the occurrence or severity of sickness could be successfully predicted based on characteristics of an individual, at-risk users could be identified, properly warned, and, perhaps, trained in some way to reduce their risk. A Personal Computer-based VR system was used to address the prediction of simulator sickness. Phase I investigated four characteristics of an individual - age, gender, mental rotation ability, and pre-exposure postural stability - which were hypothesized to be predictive of sickness. Sickness measured as …

A Study To Determine Which Factors Contribute To The Implementation Of A Successful Primary Multiage/Nongraded Program, Vicki Hils Osborne

Retrospective Theses and Dissertations

Child growth and development pedagogy suggests that not all children are ready to learn the same thing, at the same time, in the same way. Multiage/nongraded programs allow pupils to advance from one concept or skill level to the next as they are ready, regardless of age or grade, which results in continuous progress. Multiage/nongraded education has a solid foundation or research and experience to support its use. However, many questions still exist regarding the factors that contribute to the implementation of a successful primary multiage/nongraded program.

The purpose of this ethnographic study was to identify the (a) critical attributes …

The Effects Of Glucose And Fatty Acids On Enhanced Biological Phosphorus Removal Using A Sequencing Batch Reactor, Tarek Zaki Khouri

Retrospective Theses and Dissertations

Two anaerobic/aerobic sequencing batch reactors (SBRs) were used to evaluate enhanced biological phosphorus removal (EBPR). The first SBR, designated the Glucose SBR, was run for a period of four months. It received a synthetic wastewater plus glucose as a supplemental carbon source. The second SBR, the Isovaleric SBR, was run for three months. During the first month, isovaleric acid was its supplemental carbon source while for the remaining time period, no supplemental carbon source was added to the feed. Steady-state data from the SBR receiving isovalerate yielded the highest phosphorus (P) removals observed during the study, with a mixed liquor …

Analysis Of Threaded Joint Behavior In An Airbag Module Assembly, Rustam Chemat

Retrospective Theses and Dissertations

While some of think of our cars as simply "buckets of bolts", the proper design choices, applications, and assemblies of threaded fasteners/bolted joints play critical roles in automobile safety.

Supplemental Restraint Systems (SRS), more commonly known as airbags, help prevent vehicle occupants from being thrown forward into the dashboard or windshield in the event of a collision. The components comprising the airbag, the inflator, the backing plate, and the cover are connected to each other, and to the vehicle, through a series of threaded fasteners. Proper and timely deployment of the airbag depends largely on the selection of suitable threaded …

Approximate Trigonometric Expansions With Applications To Signal Decomposition And Coding, Qurban A. Memon

Retrospective Theses and Dissertations

Signal representation and data coding for multi-dimensional signals have recently received considerable attention due to their importance to several modern technologies. Many useful contributions have been reported that employ wavelets and transform methods. For signal representation, it is always desired that a signal be represented using minimum number of parameters. The transform efficiency and ease of its implementation are to a large extent mutually incompatible. If a stationary process is not periodic, then the coefficients of its Fourier expansion are not uncorrelated. With the exception of periodic signals the expansion of such a process as a superposition of exponentials, particularly …

Cavity Model Analysis Of Microstrip Ring Antennas Using Green's Functions, Javier Gomez Tagle Rangel

Retrospective Theses and Dissertations

Microstrip ring antennas have been experimentally tested by several researchers due to their specific radiation characteristics that make them very suitable for many applications, from medical uses to mobile communications. Ring antennas have been found to have a larger bandwidth compared to other conventional types of microstrip patch antennas. Further more, their size is smaller when compared to circular and rectangular resonant structures. The TM1m modes (m = 2,4,6 .. , where m represents radial variations) radiate conical beams in the broadside direction, while TM nl modes (n = 2,4,6 .. , where n represents azimuthal variations) have a radiation …

Semantic Correlation Of Behavior For The Interoperability Of Heterogeneous Simulations, Christopher James Dean

Retrospective Theses and Dissertations

A desirable goal of military simulation training is to provide large scale or joint exercises to train personnel at higher echelons. To help meet this goal, many of the lower echelon combatants must consist of computer generated forces with some of these echelons composed of units from different simulations. The object of the research described is to correlate the behaviors of entities in different simulations so that they can interoperate with one another to support simulation training. Specific source behaviors can be translated to a form in terms of general behaviors which can then be correlated to any desired specific …

Computing Optimal Cocomo Effort Multiplier Values And Optimal Casebase Subsets Using Monte Carlo Methods, Robert Joseph Maidhof

Retrospective Theses and Dissertations

There have been many studies performed and techniques applied to solve the problem of estimating man-month effort for software projects. Despite all the effort expended to solving this problem the results achieved from the various techniques have not been embraced by the software community as very reliable or accurate. This thesis uses Monte Carlo methods to obtain optimal values for COCOMO effort multipliers which minimize the average of the absolute values of the relative errors (AARE) of man-month estimate for two industry supplied casebases. For example, when using three COCOMO cost drivers (complexity, language experience, application experience) and the COCOMO …

We Can't Be The Women We Were Before: Mary Livermore And Chicago Women In The American Civil War, Nancy Arlene Driscol Engle

Retrospective Theses and Dissertations

This study examines the impact of the American Civil War on Union women by focusing on Mary Ashton Rice Livermore and her associates in wartime aid societies in Chicago, Illinois. It argues that Livermore's postwar lecture career epitomizes the new confidence that many benevolent women possessed after the Civil War. From contemporary newspaper accounts and letters it demonstrates that the conflagration broadened the scope of their activity, allowing many to hone their skills and expand their influence while remaining safely inside society's accepted gender standards. concluding that the war changed moderate white middle-class women's lives, it then illustrates that some …

Use Of Noncognitive Variables To Predict Academic Success And Retention Among A Group Of White Academically Disadvantaged College Students, Pamela Krake Fletcher

Retrospective Theses and Dissertations

At many American colleges and universities, efforts to enhance the retention of a diverse group of students have become a priority. This study represents part of this effort at the University of Central Florida, a large public suburban state university in the South. Specifically, this investigation evaluated Pegasus '95 and the Academic Mentoring Program offered in the Summer and Fall Semesters of 1995 to specially-admitted students who fell short of regular admissions requirements. During the summer, Pegasus '95 provided testing, orientation, guided course work, study skills workshops, and mentoring, both individually and in the context of cohesive socialization groups of …

Analysis Of Frequency Selective Surfaces With Ferrite Substrates, Youcheng Liu

Retrospective Theses and Dissertations

Frequency selective surfaces (FSS) have numerous applications in several microwave and optical systems. Most frequency selective surface structures have one or more dielectric substrates. In this work, instead of traditional dielectric substrates, ferrite substrates are used under different dc bias conditions. By using ferrite materials, one can change the spectral properties of these structures without physically altering them. An applied magnetic field (dc bias) on the ferrite substrate changes its properties and hence the electrical dimensions of the elements comprising the periodic structure. Thus by simply applying a dc bias, the transmission and reflection properties of the periodic structure can …

Finding Paths In The Rotation Graph Of Binary Trees, Rodney O. Rogers

Retrospective Theses and Dissertations

A binary tree coding scheme is a bijection mapping a set of binary trees to a set of integer tuples called codewords. One problem considered in the literature is that of listing the codewords for n-node binary trees, such that successive codewords represent trees differing by a single rotation, a standard operation for rebalancing binary search trees. Then, the codeword sequence corresponds to an Hamiltonian path in the rotation graph R_n of binary trees, where each node is labelled with an n-node binary tree, and an edge connects two nodes when their trees differ by a …