Digital Commons Network^™

The Link Between Smoking And Body Weight Among Adolescents, Tracey Barnett

Dissertations

Trends in smoking rates among adolescents indicate that white females generally smoke more than their adolescent counterparts, the only substance in which this occurs. Another trend in which white females far outnumber any other adolescent group is eating disorders. This study was conducted to assess the relationship between cigarette smoking and perception of weight among adolescents. A logistic regression model was constructed to test the relationship using the Adolescent Health Public Dataset. For females, there was a link between cigarette smoking and perception of overweight which was not found among the males. Similarly, white females had a significantly higher rate …

The Impact Of Systematically Varying The Duration Of Breath Samples During Infrared-Based Alcohol Breath Testing, Chris C. Clatterbuck

Dissertations

The present study set out to investigate the reliability and performance of the BAC DataMaster®, an infrared-based alcohol breath testing instrument. The focus of this study was to determine: (a) the impact of varying breath sample duration during testing, (b) if Blood Alcohol Concentration (BAC) levels produced by the DataMaster® (BAC_DM) are significantly different from BAC levels produced by analysis of whole blood (BAC_WB), and (c) if the relationship between BAC_DM estimates and BAC_WB is influenced by the amount of alcohol an examinee has ingested. Each of 27 participants was randomly assigned to one …

What Have They Told Us About Gangs? A Content Analysis Of Twentieth Century Texts On U.S. Gangs, Douglas Lee Gilbertson

Dissertations

Inspired by a scholarly desire to understand and explain things, formal theoretical explanations for the social problem of gangs have been around just about as long as gangs themselves. This is an inductive content analysis of the texts within twentieth century works explaining gangs. This study explores those explanations as social artifacts and analyzes the text within them in order to identify textual similarities. This is accomplished by consolidating codified text or words until typologies of abstract theoretical concepts are revealed. The purpose of this study is to identify probable causal factors for gang formation and gang joining behavior that …

Assessment Of The Discriminative Stimulus Effects Of (±)-3,4-Methylenedioxymethamphetamine (Mdma, "Ecstasy") And (+Lysergic Add Diethylamide (Lsd) In A Three-Lever Drug Discrimination Procedure, Amy K. Goodwin

Dissertations

(±)3,4-Methylenedioxymethamphetamine (MDMA) is a common drug of abuse known as "ecstasy." Currently, MDMA is classified into the traditional drug classes as both a "stimulant" and a "hallucinogen" because it is reported to share both subjective and physiological properties of both classes. MDMA is thought to produce its psychoactive effects by acting as both a serotonin and a dopamine agonist. However, the relative importance of the serotonin and dopamine neurotransmitter systems in mediating the stimulus properties of MDMA remains unclear.

The drug discrimination assay is used to classify drugs as "similar" or "dissimilar," as well as to examine underlying neurochemical changes …

Self-Control Training In Young Children, Laura Kay Murray

Dissertations

The incidence of conduct and behavioral disorders is steadily on the rise. Externalizing problems in the preschool years are considerable predictors of problems in later childhood, and even adulthood. There is a growing need for effective prevention programs for young children that can be implemented in school environments. Prevention efforts with young children often focus on self-control training for the reduction of impulsive behaviors. Impulsivity is an early presenting behavior pattern that can lead to a variety of disorders. The present study had two goals: (1) to measure the effects of a package intervention containing cognitive and behavioral treatment techniques …

Career Planning Needs Of Students, Carol Nowakowski

Dissertations

This study examines the perceived needs of college students in relationship to sex, employment, and academic rank. Specifically, factors that suggest the changing student population in higher education and the impact such changes have on providing career counseling services to meet student needs are presented. In addition, the differences between sex, employment status, and academic rank in relationship to perceived career planning needs is presented based on a review of literature. Results of a survey to students attending Davenport University (formerly known as Davenport College) during the winter 1995 semester are summarized in terms of perceived career planning needs based …

Differences Among Accredited Athletic Training Education Programs In Preparing Students For The National Certification Examination, Donna M. Ritenour

Dissertations

A retrospective quantitative study that surveyed all of the CAAHEP accredited athletic training education programs was performed. The purpose of this study was twofold: (I) what are the institutional and programmatic characteristics associated with the colleges/universities that sponsor CAAHEP accredited entry level athletic training education programs, and (2) do these differences significantly alter the preparedness of students for the athletic training profession. Athletic Training Education Programs that were developed prior to 1993 were compared to those programs that were developed after 1993 to determine if institutional or programmatic characteristic differences exist among the Colleges/Universities that sponsor CAAHEP accredited entry level …

The Adjustment Problems Of African Students At Western Michigan University, Apollos Bitrus Goyol

Dissertations

There are more international students enrolled in colleges and universities in the U.S. than in any other country as reported by the Institute of International Education. In the 2000/01 school year, the institute estimated that 547,867 international students were studying in the U.S. Most of these students, 302,058 (55%) came from countries in Asia; and 80,584 (14.7%) came from Europe. Latin America had 63,634 (11.6%); followed by the Middle East, with 36,858 (6.7%); Africa, with 34,217 (6.2%); North America, with 25,888 (4.7%), and Oceania, with 4,624 (.8%). Ten students were Stateless. As a response to the high number of international …

Local Symmetries Of Symmetrical Cayley Maps, Paula T. Smith

Dissertations

Graphs, groups, and surfaces are all subjects of study in topological graph theory, using techniques and principles from the disciplines of graph theory, algebra, and topology. A Cayley graph provides a graphical representation of a finite group and a fixed generating set for the group; a Cayley map is a two-cell imbedding into a surface of a Cayley graph such that labeled outward-directed darts occur in the same sequence at each vertex. A dart is a directed edge. In this work, we generalize Cayley maps to allow two-cell imbeddings of graphs with loops and multiple edges.

In this thesis, we …

Bi-Axially Loaded Slender Reinforced Concrete Columns Subjected To Sustained Loads, Song Gu

Dissertations

A generalized analytical approach is presented in this research to predict the behavior both of slender and short reinforced concrete columns under sustained biaxial eccentric load.

The present analysis proposes equations established at a cross section of a reinforced concrete column by combining force equilibrium, constitutive law, and compatibility conditions. The strain and curvature of each section and the deflection of the column can then be obtained and resolved.

The established creep computation models, recommended separately by American Concrete Institute (ACI) 209R-92 and the Comite' Euro-International du Be'ton (CEB)-FIP 1990 Model Code have been used to calculate creep and shrinkage …

Nonlinear Interfacial Stability Of Core-Annular Film Flows In The Presence Of Surfactants, Said A. Kas-Danouche

Dissertations

This work is an analytical and computational study of the nonlinear interfacial instabilities found in core-annular flows in the presence of surfactants. Core-annular flows arise when two immiscible fluids (for example water and oil) are caused to flow in a pipe under the action of ail axial pressure gradient. In one typical type of flow regime, the fluids arrange themselves so that the less viscous (e.g. water) lies in the region of high shear near the pipe wall, with the more viscous fluid occupying the core region. Tech nologically, this arrangement provides an advantage since the highly viscous fluid is …

The Development Of H Homogeneous Nucleation Rate Model For Thermoplastic Foams Based On A Molecular Partition Function And Fickian Diffusion, Ronald G. Gabbard

Dissertations

An improved homogeneous nucleation rate model for thermoplastic foams has been developed. This model does not rely on experimentally determined parameters and only uses pure component physical property data and a binary diffusion coefficient. This model, like those derived from classical nucleation theory, is made up of two parts, one that determines the size of the energy barrier in the nucleation process and one that estimates the forward rate of the process. A statistical-mechanical approach was used to create an energy term that is based on a molecular partition function. In this approach, the bulk phase (polymer and blowing, agent …

Destructive Disassembly Of Bolts And Screws Using Impact, Kyung Geun Pak

Dissertations

Disassembly, the process of separating parts or components at the end of their useful life is complex due to a variety of fastener shapes and variability in their damage during use. As a natural solution, mechanical impact has been suggested as a cost-effective method for destructive disassembly of joining elements.

The objective of this research is to improve the efficiency of impact disassembly process by studying the characteristics of elastic waves caused by impact. This research presents a new method for increasing the shear stress applied on the bolt head without increasing the energy input invested on launching striker. The …

Complete Stress-Strain Characteristics Of High Performance Concrete, Insang Lee

Dissertations

High performance concrete (HPQ has recently become a widely used concrete construction material for modem buildings, bridges, and pavements, etc. To produce such a better quality of concrete, chemical and mineral admixtures such as fly ash, slag cement, and silica fume, ground granulated blast furnace slag, as well as air-entraining agents are commonly used in the field construction. It has been found that high perforinance concrete can improve the workability, ultimate strength and durability of the concrete. However, the enhancement of ductility in concrete, and concrete structures as a whole is still inconclusive and needs more research. The ductility can …

Temporal Synchronization Of Ca1 Pyramidal Cells By High-Frequency, Depressing Inhibition, In The Presence Of Intracellular Noise, Stephen A. Kunec

Dissertations

The Sharp Wave-associated Ripple is a high-frequency, extracellular recording observed in the rat hippocampus during periods of immobility. During the ripple, pyramidal cells synchronize over a short period of time despite the fact that these cells have sparse recurrent connections. Additionally, the timing of synchronized pyramidal cell spiking may be critical for encoding information that is passed on to post-hippocampal targets. Both the synchronization and precision of pyramidal cells is believed to be coordinated by inhibition provided by a vast array of interneurons. This dissertation proposes a minimal model consisting of a single interneuron which synapses onto a network of …

Experimental And Theoretical Study Of An Integrated Silicon Mach-Zehnder Interferometer For Chemical Sensing Applications, Yew Fong Hor

Dissertations

This thesis involves the design, fabrication and characterization of an integrated optical waveguide sensor. Prior to fabrication, design parameters of the waveguide need to be determined and optimized. The waveguide parameters such as waveguide dimension and the refractive index of the core and cladding are obtained from the single-mode cutoff frequency calculated using either analytical or numerical methods. In this thesis, details of analytical calculations to determine the cutoff frequency in terms of the waveguide parameters will be presented. The method discussed here is Marcatili's approximation. The purpose is to solve the scalar wave equation derived from Maxwell's equations because …

Instability Of Electrified Viscous Films, Knograt Savettaseranee

Dissertations

We examine the stability of a thin two-dimensional liquid film with a regular electric field applied in a direction parallel to an initially flat bounding fluid interface. We study the distinct physical effects of surface tension, van der Waals and electrically induced forces for a viscous incompressible fluid. The film is assumed to be sufficiently thin, and the surface tension and electrically induced forces are large enough that gravity can be ignored to the leading order. Our target is to analyse the nonlinear stability of the flow. We attain this by deriving and numerically solving a set of nonlinear evolution …

Development And Characterization Of Methodology And Technology For The Alignment Of Fmri Time Series, Carlo Ciulla

Dissertations

This dissertation has developed, implemented and tested a novel computer based system (AUTOALIGN) that incorporates an algorithm for the alignment of functional Magnetic Resonance Image (fMRI) time series. The algorithm assumes the human brain to be a rigid body and computes a head coordinate system on the basis of three reference points that lie on the directions correspondent to two of the eigenvectors of inertia of the volume, at the intersections with the head boundary. The eigenvectors are found weighting the inertia components with the voxel's intensity values assumed as mass. The three reference points are found in the same …

Theory And Design Of Mixed Lumped-Distributed Cross-Coupled Filters With Applications To Linear Phase Shifter And Tunable Filters, Sanghoon Shin

Dissertations

Using cross-coupled networks of a new concept, transmission zeros were efficiently located in the complex frequency-domain. With this approach, the group delay and attenuation slope of the circuit network can be controlled to get both sharp rejection characteristics and linear phase slopes. In order to achieve this performance, various types of combline filters are suggested. Various simulation tools (commercial linear circuit and E-M simulators), as well as the developed pole-zero locator program, were used to design a new class of cross-coupled networks. In particular, the polezero locator program can be used to extract an equivalent circuit of the topology that …

Two-Dimensional Reflectivity Polarization Elastometry Imaging Techniques (Piet) Of Soft Tissue, Hee Chuan Lim

Dissertations

A non-invasive polarized light reflection measurement method to measure the stretch of soft tissue, such as skin, is described. The technique utilizes changes in the reflectivity of polarized light intensity as a monitor of skin stretch. Measurements on in-vitro pigskin and invivo human skin show that the reflectivity of polarized light intensity increases linearly with stretch over a range. The changes in diffusive reflectivity properties of skin result from the alterations that take place in the roughness across the thickness of the skin layers due to stretch. Conceptually, as the roughness of a layer decreases with stretch, a smoother reflecting …

Process Control Of A Laboratory Combustor Using Neural Networks, Thana Slanvetpan

Dissertations

Active feedback and feedforward-feedback control systems based on static-trained feedforward multi-layer-perceptron (FMLP) neural networks were designed and demonstrated, by experiment and simulation, for selected species from a laboratory two stage combustor. These virtual controllers functioned through a Visual Basic platform. A proportional neural network controller (PNNC) was developed for a monotonic control problem - the variation of outlet oxygen level with overall equivalence ratio (Φ₀). The FMLP neural network maps the control variable to the manipulated variable. This information is in turn transferred to a proportional controller, through the variable control bias value. The proposed feedback control methodology …

Analysis Of Costs And Delivery Intervals For Multiple-Release Software, High-Way Sun

Dissertations

Project managers of large software projects, and particularly those associated with Internet Business-to-Business (B2B) or Business-to-Customer (B2C) applications, are under pressure to capture market share by delivering reliable software with cost and timing constraints. An earlier delivery time may help the E-commerce software capture a larger market share. However, early delivery sometimes means lower quality. In addition, most of the time the scale of the software is so large that incremental multiple releases are warranted.

A Multiple-Release methodology has been developed to optimize the most efficient and effective delivery intervals of the various releases of software products, taking into consideration …

Experimental Studies Of Wave Propagation In Three-Dimensional Photonic Crystals, John M. Tobias

Dissertations

Photonic crystals were proposed fifteen years ago. Propagation is selectively prevented through these crystals resulting in a photonic band gap, that is, a frequency region where light cannot propagate. These frequency bands are analogous to electronic band gaps in solid-state crystals.

The optical properties of the photonic crystal in regions near the band gap remain relatively unexplored. Yet, there is significant evidence to suggest that this avenue of investigation can provide useful optical and microwave applications. Numerical studies have predicted that the effective permittivity near the photonic band gap approaches zero and becomes negative. Selfcollimation of the propagating beam and …

A Bi-Level Programming Approach For The Shipper-Carrier Network Problem, Ya Wang

Dissertations

The Stackelberg game betweenshippers and carriers in an intermodal network is formulated as a bi-levelprogram. In this network, shippers make production, consumption, androuting decisions while carriers make pricing and routing decisions.The oligopolistic carrier pricing and routing problem, which comprisesthe upper level of the bi-level program, is formulated either as a nonlinearconstrained optimization problem or as a variational inequality problem,depending on whether the oligopolistic carriers choose to collude orcompete with each other in their pricing decision. The shippers' decisionbehavior is defined by the spatial price equilibrium principle. Forthe spatial price equilibrium problem, which is the lower level of thebi-level program, a …

An Analysis Of Field Data For Evidence Of Anaerobic Degradation Of Pah And Btex Plumes At Manufactured Gas Plant Sites, Georgene Mortimer

Dissertations

Field data (including geology, hydrogeology, soil chemistry, groundwater chemistry, and aquifer characteristics) were analyzed at eight MGP sites located in the New Jersey Coastal Plain. These data were used to calculate biodegradation rate constants, which were then compared with laboratory microcosm data and published values. Isopleths were drawn from the field data to indicate the dominant biodegradation mechanisms at each of the sites, and stoichiometric calculations were used to determine the total capacity of the electron acceptors present to degrade the plume contaminants. In examining these data, the protocol described by the Air Force Center for Environmental Excellence (AFCEE) was …

Development Of Icejet-Based Surface Processing Technology, Dimitri V. Shishkin

Dissertations

The objective of the proposed work is to acquire knowledge needed for the development and deployment of manufacturing processes utilizing the enormous technological potential of water ice. Material removal by blasting with ice media such as particles, pellets and slugs was investigated. The ice media was accelerated by entrainment in a fluid stream (air, steam, liquid water, supercritical C0₂), impact of rotating blades, fluid expansion, etc. The ice-airjet has to replace sand blasting and the ice-waterjet has to replace the abrasive waterjet. Based on these results, technical approaches for surface processing and machining will be improved. A primary …

Collaborative Problem Solving And Program Development Model, Joanna Defranco-Tommarello

Dissertations

A model to enhance collaborative problem solving and program development is presented. The collaborative model is a detailed cognitive model that takes into consideration the cognitive and social activities that occur during collaborative problem solving and program development. The cognitive activities required for collaborative problem solving and program development are identified and integrated into a six-stage model. An extensive literature review in the associated fields is presented to show the need for the model described in this dissertation. In addition, a comprehensive study of tools to support collaboration during problem solving and program development was also performed as well as …

Concurrent Evaporating Spray Jets In Dilute Gas-Solid Pipe Flows, Xiaohua Wang

Dissertations

Evaporating spray jets into gas-solids suspensions are encountered in many industrial applications. The rapid evaporation of spray jets has significant effects on the gas-solids mixing near the jet nozzle regions, including non-uniform solids concentration dilution, gas/solids temperature reduction, and gas/solids velocity acceleration. Furthermore, the jet structure is altered by the change of solids loading, jet mass flow rate and initial droplet size distribution. These interactions of gas, solids and evaporating droplets dominate the process efficiency and product quality. There is an urgent need for exploring fundamental mechanisms of the multi-phase interactions with heat and mass transfer as there are few …

Prenatal Maternal Attachment: The Lived Experience, Regina Ann Leva-Giroux Dnsc

Dissertations

Prenatal maternal attachment and the practice of health promoting behaviors during pregnancy are considered universal phenomena to women. Yet, the understanding of these phenomena from the lived experiences of pregnant women has not been well researched. The purpose of this phenomenological study was to describe the experience of maternal attachment to the unborn child and how that attachment might relate to the practice of these behaviors during pregnancy. The participants in this study were ten English speaking women, college educated, professionally employed, who were pregnant for the first time. Unstructured interviews were conducted with the participants at 14–16 weeks and …

Role Perceptions Of School Nurses Who Work With Medically Fragile Students, Cay Chapman Casey Phd

Dissertations

In 1999, the Supreme Court ruled that school districts were financially responsible to provide related services including nursing services, to medically fragile students. This decision applied to children attending public schools who have complex health problems and are tracheostomy dependent. The purpose of this grounded theory study was to explore role perceptions of eighteen school nurses caring for these children in classrooms. Six dimensions emerged from the data: Promoting Family/Nurse Connections, Adapting the Environment, Claiming Authority, “Standing Out There”, Striking a Balance and Experiencing Success. Promoting Family/Nurse Connections emerged as the central perspective, essential to implementing a plan of care. …