Digital Commons Network^™

Comparison Of Curriculum Content On Behavioral Strategies For Managing Anxious Clients In Associate And Baccalaureate Degree Dental Hygiene Programs In The United States, Darnyl Marie King

Dental Hygiene Theses & Dissertations

Dental anxiety, a pervasive problem in the general population, is an important client management concern for dental hygienists. This study sought to determine the type and amount of instruction in United States dental hygiene programs in terms of behavioral strategies for the management of anxious clients, the difference in instruction between associate and baccalaureate degree dental hygiene programs, and the opinions of dental hygiene educators regarding these strategies. A self-designed, 19-item questionnaire entitled the King Behavioral Management Questionnaire was used to obtain data on a sample of 210 accredited dental hygiene programs. Part one of the questionnaire consisted of questions …

Progressive Failure Analysis Methodology For Laminated Composite Structures, David Wayne Sleight

Mechanical & Aerospace Engineering Theses & Dissertations

A progressive failure analysis model has been developed for predicting the nonlinear response and failure of laminated composite structures. The progressive failure analysis uses C¹ plate and shell elements based on classical lamination theory to calculate the in-plane stresses. Several failure criteria, including the maximum strain criterion, Hashin's criterion, and Christensen's criterion, are used to predict the failure mechanisms and several options are available to degrade the material properties after failures. The progressive failure analysis model is implemented in COMET and can predict the damage and response of a laminated composite structures from initial loading to final failure.

Exploring Knowledge Processes For Technology Assimilation, Rochelle K. Young

Engineering Management & Systems Engineering Theses & Dissertations

In the emerging knowledge society, the ability to make the experience and expertise of those involved in and affected by new technology unconditionally available to all members of an organization is becoming increasingly important. One of the problems in developing such knowledge processes for technology assimilation is that current social structures do not easily accommodate unconditional participation. Since the implementation of modern information technology is changing the workplace and the nature of work itself, alternative social structures are needed. This research takes as given that deep questions concerning knowledge processes and social transformation are in principle undecidable; and, only questions …

Lattice Truss Structural Response Using Energy Methods, Winfred Scottson Kenner

Mechanical & Aerospace Engineering Theses & Dissertations

A deterministic methodology is presented for developing closed-form deflection equations for two-dimensional and three-dimensional lattice structures. Four types of lattice structures are studied: beams, plates, shells and soft lattices. Castigliano's second theorem, which entails the total strain energy of a structure, is utilized to generate highly accurate results. Derived deflection equations provide new insight into the bending and shear behavior of the four types of lattices, in contrast to classic solutions of similar structures. Lattice derivations utilizing kinetic energy are also presented, and used to examine the free vibration response of simple lattice structures. Derivations utilizing finite element theory for …

Rectified Synthesis Of Coupler Driven Four Bar Mechanisms For Two And Three Position Motion Generation, Ramanujam Thiruvenkatachari

Mechanical & Aerospace Engineering Theses & Dissertations

Four-bar mechanisms are widely used in the industry to solve a variety of motion problems. Till recently, their design was based on fundamental kinematics and brute force techniques, resulting in impractical designs and spurious linkages that failed to perform their desired functions effectively.

Procedures have been developed and implemented to guide the rigid body of crank driven four-bar linkages, through a set of design positions with techniques to avoid their defects. However, the practical applications of linkages used in the industry are coupler driven, with primitive synthesis procedures based on trial and error. The opening and closing of the hood …

A Study Of The Numerical Implementation Of Multidisciplinary Design Optimization Strategies, Rodney A. Taylor

Mechanical & Aerospace Engineering Theses & Dissertations

Design optimization provides an organized, systematic, and efficient method for obtaining design improvements based upon a specified measure of design performance. In the multidisciplinary design optimization (MDO) environment efficient optimization techniques allow complex designs to be improved by managing conflicting disciplinary design goals so as to improve the global design. This thesis studies the implementation issues surrounding MDO techniques and strategies. To facilitate this investigation two testbed problems have been selected for study. These problems consider two approaches to the conceptual design of an aeroelastic wing. The first approach is based on an idealized, two-dimensional representation of an airfoil under …

Visual Speech Recognition Using Multiple Deformable Lip Models, Devi Chandramohan

Electrical & Computer Engineering Theses & Dissertations

Motivated by the fact that human speech perception is a bimodal process (auditory and visual), several researchers have designed and implemented automatic speech recognition (ASR) systems consisting of both audio and visual subsystems, and shown improved performance relative to traditional purely auditory systems. Several visual speech reading approaches have used deformable templates to model the shape of a speaker's lips. Deformable templates are models of image objects, which can be deformed by adjusting a set of parameters to match the object in some optimal way, as defined by a cost function. Using a single deformable lip model has disadvantages such …

Two-Dimensional Drift-Diffusion Simulations Of Silicon Avalanche Shaper (Sas) Devices For High Power Applications, Hamid Jalali

Electrical & Computer Engineering Theses & Dissertations

Silicon Avalanche Shaper devices have been projected as being important components of an inexpensive, semiconductor-based technology for high power switching applications. The primary advantage of this technology is that it is based on Silicon material which is easy to fabricate and has a well established processing technology. Unlike other high power technologies, the SAS devices do not rely on external optical triggering which eliminates the need for lasers and related optical circuitry.

The SAS based high power switching technology has been pioneered and tested by a Russian group. Though preliminary results have been very encouraging, the device reliability and its …

Neural Generalized Predictive Control For Real-Time Control, Donald I. Soloway

Electrical & Computer Engineering Theses & Dissertations

In this thesis a computationally efficient Generalized Predictive Control (GPC) algorithm is presented and implemented. The algorithm is more efficient than others because the number of iterations needed for convergence is significantly lower with Newton-Raphson. The main additional cost with Newton-Raphson algorithm is the calculation of the Hessian. This overhead is not a problem because of the reduced number of iterations, making the algorithm suitable for real-time control. For nonlinear control applications, a neural network is used as a dynamical system predictor leading to a Neural Generalized Predictive Control (NGPC) algorithm which is presented in detail in this thesis. An …

A Test Of An Alternate Calibration Matrix For Niosh Method 7300, Robert T. Vitek

Community & Environmental Health Theses & Dissertations

The purpose of this study was to determine if the analytical results (when determining cadmium, lead, and zinc concentrations) for air sample filters prepared and analyzed according to N:OSH Method 7300, differ significantly, from those obtained when the instrument is calibrated using EPA Method 200.7 acid matrix standards. The null hypothesis was that no statistically significant difference, measured at the 95% confidence level, would exist between results obtained from the two calibration standards. Careful standard and sample preparation, the use of an internal standard, and the application of working standard and working internal standard correction factors served to isolate the …

Seasonal And Mesoscale Variability In The Distribution Of Antarctic Krill, Euphausia Superba, West Of The Antarctic Peninsula, Cathy Meyer Lascara

OES Theses and Dissertations

Observations collected between November 1991 and September 1993 during four multidisciplinary cruises were analyzed to provide a description of seasonal and mesoscale variability in the distribution and abundance of Antarctic krill, Euphausia superba, within continental shelf waters west of the Antarctic Peninsula and to investigate possible relationships between variability in krill distributions and variability in selected environmental parameters. Acoustic measurements of krill were made each season at designated locations to estimate the abundance of krill, in terms of vertically-integrated krill biomass and the number of aggregations, characterize the depth distribution of krill, and provide a quantitative description of the size, …

Factors Affecting Nitrogen Fixation Rates In Termites (Isoptera: Rhinotermitidae: Reticulitermes) And Termite Nitrogen Contributions Of Forest Ecosystems, Anthony Duane Curtis

Biological Sciences Theses & Dissertations

Termites host symbiotic bacteria that fix atmospheric nitrogen, which makes termites important in the biogeochemical cycling of nitrogen in ecosystems. The objective of this study was to estimate annual nitrogen contributions by termites by examining seasonal rates of nitrogen fixation, seasonal abundance of different termite castes and their nitrogenase activity, the effects of dietary nitrogen on nitrogenase activity, and low oxygen and high carbon dioxide atmospheres on termite nitrogenase activity, and the accuracy of mark-recapture studies to estimate termite population size.

Termite nitrogen fixation rates were monitored monthly for 10 Reticulitermes Holmgren colonies from June, 1993, to December, 1995. Rates …

The Effects Of Environmental Variability On The Population Structure Of The Eastern Oyster (Crassostrea Virginica): A Modeling Study, Margaret Mcmanus Dekshenieks

OES Theses and Dissertations

Three models were coupled to investigate the effects of changes in environmental conditions on the population structure of the Eastern oyster, Crassostrea virginica. The first model, a time-dependent model of the oyster population as described in Powell et al. (1992) and Hofmann et al. (1992, 1995), tracks the distribution, development, spawning, and mortality of sessile oyster populations. The post-settlement model incorporates mortality through parasitism, predation, food depletion and extremes in environmental conditions. The post-settlement model supplies the initial abundance of larvae spawned into the water column, and in turn is the recipient of cohorts of spawn which survive through metamorphosis. …

Pion Absorption On Polarized Lithium-7 At 165 Mev, Thomas A. Greco

Physics Theses & Dissertations

Pion absorption is not well understood. Cross section data alone does not provide a complete description since the cross section tends to be sensitive only to the spin-independent terms in the transition amplitude. Polarization observables are thus necessary to complete the picture. In this experiment, analyzing powers for the reaction ^7→Li(π⁺,pp)⁵He at T_π = 165 MeV were measured at the Paul Scherrer Institut, Switzerland. The emitted protons were detected with the SUSI spectrometer at 38° in coincidence with an array of five scintillator telescopes centered around the quasi-free angle for absorption on a nucleon …

A Receiving Water Quality Model For Dissolved Metal Runoff From A Floating Drydock, Thomas O. Fenn

Civil & Environmental Engineering Theses & Dissertations

A methodology for modeling the water quality mixing zone of dissolved metal bearing storm water runoff is presented with specific application to floating drydocks in a tidal estuary. The method relies upon a solution of the mass balance equation as contained in the computer program, Water Quality Analysis Simulation Program (WASPS), an Environmental Protection Agency (EPA) model. Separate applications are presented for dissolved metal and solid settling to optimize the WASPS program capabilities.

WASPS provides the capability to evaluate the mass balance equation in a finite difference scheme applied over a large number of small volume segments. The program may …

Petrochemical Analysis By Remote Fiber-Optic Raman Spectroscopy And Partial Least Squares Regression Analysis, Philip Edmund Flecher Jr.

Chemistry & Biochemistry Theses & Dissertations

A dispersive Raman system with charge coupled device (CCD) detection, distributed Bragg reflector (DBR) diode laser excitation, and a fiber optic probe has been developed for the rapid analysis of petrochemicals and fuels. Initially, mock petroleum fuels with analyte concentrations from 1.S - 16% were prepared and analyzed with the system. The inability of the original index guided diode laser to maintain a constant frequency during the mock petroleum analysis was a recurrent problem. The DBR laser was subsequently shown to have stability superior to index guided lasers, and was used in the remainder of the research.

Real gasoline samples …

Recruitment Of Blue Crab, Callinectes Sapidus, Postlarvae To The Back-Barrier Lagoons Of Virginia's Eastern Shore, Robert D. Brumbaugh

OES Theses and Dissertations

Most research on the early life history of the blue crab, Callinectes sapidus, has been conducted in large partially stratified estuaries such as the Chesapeake Bay. In contrast, little is known about the recruitment dynamics or habitat requirements of blue crab postlarvae (megalopae) in shallow well-mixed lagoonal systems that make up a considerable part of the species' range. In Virginia's coastal lagoons, planktonic blue crab megalopae are most abundant at night on flooding tides, and are not abundant during the daytime or on ebbing tides. This appears to enhance retention within the lagoons, despite the short residence time of water …

Dynamic Lot Sizing And Scheduling In A Multi-Item Production System, Padmanabhan Soundar

Engineering Management & Systems Engineering Theses & Dissertations

In this research, algorithms are developed to address the problem of dynamic lot sizing and scheduling in a single level (or single operation) production system. This research deviates from previous research in this area in that it does not have the kind of assumptions regarding the real world production system that normally were made to reduce the complexity of the problem. Specifically, this research explicitly considers finite capacity, multiple items, known deterministic dynamic demand, sequence dependent setup times and setup costs, setup carryover and variable backlogging. The objective is to simultaneously determine the lot size and the sequence of production …

Two-Photon Quantum Interference Polarization Spectroscopy: Measurements Of Transition Matrix Elements In Atomic Rubidium, Alexander I. Beger

Physics Theses & Dissertations

The estimation of the adequacy of theoretical calculations on the atomic structure requires availability of the precise experimental data on radiative properties of the atoms. Such data is also required in astronomy and some important areas of technology. The lack of precision of traditional spectroscopic studies of atom presents a fundamental obstacle for progress in these areas. For example, in atomic rubidium, the best precision of the traditional spectroscopic results is on the order of about 1 - 5%, which does not allow for clear assessment of the latest sophisticated theoretical calculations on atomic rubidium structure, with emphasis on different, …

Correlates Of The Mmpi-A Immaturity (Imm) Scale In An Adolescent Psychiatric Population, Eric Albert Imhof

Psychology Theses & Dissertations

Despite numerous theories of adolescent ego development, there is no objective measure of ego development or maturation targeted for the assessment of adolescents. The Immaturity (IMM) Scale developed for the Minnesota Multiphasic Personality Inventory - Adolescent (MMPI-A) was designed to fill this void in adolescent assessment. The present study examined the concurrent validity of the IMM Scale based on sixty-six adolescents (13-18 years old) in an inpatient setting using four prominent measures of maturity, i.e., The Defining Issues Test (DIT), the Washington University Sentence Completion Test (WUSCT), the Extended Objective Measure of Ego Identity Status - Second Revision (EOM-EIS-2), and …

An Approach For Multidisciplinary Design Optimization, Robert V. Krueger

Mechanical & Aerospace Engineering Theses & Dissertations

Multidisciplinary Design Optimization (MDO) is an optimization technique that allows complex designs to be improved by managing conflicting goals in such a fashion so as to improve the overall design. This thesis presents a nonhierarchic MDO formulation and gives a general explanation of how it is to be applied to various appropriate problems. In addition, this thesis evaluates the viability of this MDO technique by applying it to two distinct, multidisciplinary problems that have been used as examples in other literature. The first example problem is a combined aerodynamic/structural problem and the second example is an alkylation process problem. First, …

Visibility-Related Problems On Parallel Computational Models, Himabindu Gurla

Computer Science Theses & Dissertations

Visibility-related problems find applications in seemingly unrelated and diverse fields such as computer graphics, scene analysis, robotics and VLSI design. While there are common threads running through these problems, most existing solutions do not exploit these commonalities. With this in mind, this thesis identifies these common threads and provides a unified approach to solve these problems and develops solutions that can be viewed as template algorithms for an abstract computational model. A template algorithm provides an architecture independent solution for a problem, from which solutions can be generated for diverse computational models. In particular, the template algorithms presented in this …

Linear Models For Multivariate Repeated Measures Data, Shantha S. Rao

Mathematics & Statistics Theses & Dissertations

In this dissertation we focus mainly on the analysis of continuous multivariate repeated measurements data based on the assumption of multivariate normality. However certain aspects of the analysis of univariate repeated measures data are also considered. Typically, we have measurements on p variables (possibly correlated) in the form of px1 vectors y_ijk observed at k = 1,2, ...,t_ij occasions on j = 1,2, ..., n_i individuals from i = 1,2, ..., g groups. We assume a naturally occurring covariance structure V_ij ⊗ ∑ among the p variables on the j^th individual from i^th group …

The Relationship Of Foot Types To Pressure Distribution Patterns Of The Forefoot During Gait, Hui-Ji Fan

Rehabilitation Sciences Theses & Dissertations

Pressure distribution under the foot has been considered a useful indicator in the treatment of foot problems. The purpose of this study was to determine the relationship between foot types and pressure patterns under the forefoot. Fifty-four healthy subjects (19 males, 35 females, mean age=27 years, S0=4, range=21-39) participated in this study. A BTE pedobarograph was used to record pressure distribution under the foot during barefoot walking. Foot types were classified as neutral, pronated, and supinated. Pressure distribution under the forefoot was classified as medial, central, and lateral patterns. The medial pattern had the highest peak pressure under the first …

Observation Of Shelfwater Overrunning The Southern Slope Sea, Ajoy Kumar

OES Theses and Dissertations

Analyses of two years (1992 and 1993) of high resolution (1.47 km²) sea surface temperature satellite images of the southern Mid-Atlantic Bight (MAB), showed that unusually extensive overhang of shelf water occurs episodically, and coherently over along shelf distances of several hundred kilometers. These episodes are dubbed overrunning of the Slope Sea by shelf water. The overrunning volume has a "face" and a "back" (southern and northern limit). It transports substantial quantities of shelf water southward, and does not retreat onto the shelf, but eventually joins the western edge of the Gulf Stream in the vicinity of Chesapeake …

Animal-Word And Sound Test: An Auditory Cognitive Interference Effect, Jason L. Parker

Psychology Theses & Dissertations

This study presented a method in which the Stroop Color Word Test can be adapted to an auditory form. This auditory test used a series of animal words, animal sounds and word-sound combinations. This "Animal-Word-and-Sound test" contained three subtests. The test tasks were to repeat a list of words, identify a list of animal sounds, and to identify the sound in a combined animal word-sound pairings (Both the animal's name and sound are presented simultaneously). An alternate form of this audio test was examined. The alternate form followed the same construction except in the final condition, the task was to …

Frequency Response Enhancement Of A Flow Sensor Using Diamond Thin Films Synthesized By Plasma Cvd, John Curren Hagwood

Electrical & Computer Engineering Theses & Dissertations

Theoretical modeling conducted previously in our Microelectronics Laboratory has shown that a layer of diamond film inserted between a metal film and a substrate will enhance the frequency response of a conventional thin film flow sensor. This thesis involved fabricating and testing a conventional thin film sensor of nickel on quartz (Ni/Q) and a diamond enhanced sensor (Ni/D/Q) for comparative frequency response analysis to validate the theory. Diamond films were grown onto quartz substrates using a microwave plasma enhanced chemical vapor deposition process. Conditions were established to synthesize continuous diamond films on quartz substrates. These films were characterized by scanning …

Wavelength Modulation Spectroscopy With Diode Lasers, Ying Lu

Electrical & Computer Engineering Theses & Dissertations

Wavelength Modulation Spectroscopy is a non-intrusive technique which enables several parameters such as concentration, velocity, and temperature of a target specie to be measured. The method involves a modulation of a probe laser beam and detection at the fundamental, or any harmonic frequency, by a phase-sensitive apparatus. The theory of wavelength modulation is discussed. Effects of the finite value of the wavelength modulation index, together with the effects of any residual amplitude modulation that often occurs simultaneously in a diode laser, are included. It is shown that there are several advantages in using detection harmonics orders greater than the second. …

Finding Godot: Postmodernism And Truth, Robert T. Gregory Jr.

Institute for the Humanities Theses

Postmodernism has enjoyed a wide range of influence as a critical enterprise, often being accused as nothing more than a method of critique. In addition, it is often objected that postmodernism advocates a radical relativism which is ultimately self-contradictory and lacks an overall sense of agency that can apply to concrete action. These issues are particularly significant when considering theories of truth. Given postmodernism criticizes traditional notions of truth and objectivity, it is appropriate to ask if postmodernism possesses a positive position on truth as an alternative. I argue in this work that while postmodernism has a significant critical enterprise, …

An Enzyme-Linked Immunosorbent Assay For The Detection Of Cardiac Myoglobin Using Monoclonal Antibodies, Deborah F. Kelly

Chemistry & Biochemistry Theses & Dissertations

The most prevalent life-threatening disease worldwide, secondary to coronary artery thrombosis is Acute Myocardial Infarction (AMI). Increases in three clinical markers have been explored as an early means of AMI detection: Cardiac myoglobin, and the two specific cardiac isoforms of Creatine Kinase, CK-MM and CK-MB. However, myoglobin levels have shown to give a more accurate correlation (R = 0.89) than does Creatine Kinase evaluation. Therefore, we have developed a two-site Enzyme-Linked Immunosorbent Assay (ELISA) using monoclonal antibodies against myoglobin isolated from human heart tissue. This assay is based on specific anti-genantibody interactions and is sensitive at the nanogram level. We …