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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Comparing Math Self-Efficacy In Middle School Girls, Anagloria Rodriguez Dec 2003

Comparing Math Self-Efficacy In Middle School Girls, Anagloria Rodriguez

Graduate Theses, Dissertations, and Problem Reports (ETD)

There have been no previous studies in the self-efficacy or single-sex schools literature that have looked at the possible relationship between self-efficacy expectations and type of school. This study compared mathematics self-efficacy of sixth, seventh, and eighth grade girls in a single-sex and a co-educational school. Four measures, including a personal background questionnaire, were used to collect data. Results showed a correlation for type of school and importance of mathematics. Contrary to assumptions made by the researcher, girls in the co-educational school scored consistently higher on all measures used. The results of this research suggest that it will take more …

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Evaluation Of 4.75 Mm Superpave Mix Criteria For West Virginia, David Diazgranados Diaz Dec 2003

Evaluation Of 4.75 Mm Superpave Mix Criteria For West Virginia, David Diazgranados Diaz

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this research was to evaluate design parameters for 4.75 mm nominal maximum aggregate size mixes, NMAS, in West Virginia. This research was divided in two phases. During Phase I, evaluation of Superpave criteria for 4.75 mm LAMAS mixes, a variety of 4.75 mm NMAS limestone mixes were developed following Superpave methodology for low traffic volume. In Phase II, natural sand evaluation for 4.75 mm mixes; three approved Marshall designs were obtained from the WVDOT. Two of the mixes contained natural sand and the other was a 100 percent limestone mix. The Marshall mix designs were verified and …

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Hybrid Neural Networks Models For A Membrane Reactor, Mohammed Al-Yemni Dec 2003

Hybrid Neural Networks Models For A Membrane Reactor, Mohammed Al-Yemni

Graduate Theses, Dissertations, and Problem Reports (ETD)

Artificial neural networks (ANN) have become an established discipline and have gained extensive interest within chemical engineering. In recent years, research effort has focused on the use of "hybrid artificial neural networks" (HANN) models that combine both the deterministic and the ANN elements. Several methods have been proposed for combining ANN with first principle relations. In this thesis, a new hybrid scheme, which is similar to that developed by Kasprow for a space-independent and time-dependent fed-batch microbial reactor, was developed for a space-dependent steady-state enzymatic reactor. This scheme combines ANN with mass balances and assumed rate expressions. It was shown …

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Years Of Teaching Experience And Descriptions Of Educational Situations, Dana J. Stapleford Dec 2003

Years Of Teaching Experience And Descriptions Of Educational Situations, Dana J. Stapleford

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study examined the relationship between years of teaching experience and the type of descriptions given of educational situations. Participants were certified teachers with 1 to 27 years of teaching experience and preservice teachers with 0 years of teaching experience. A coding system was developed as an objective method for extracting participants' descriptions of actions and consequences pertaining to student and teacher behavior. Results did not support the original hypothesis that a relationship would be found between years of teaching experience and the descriptions made. However, several other relationships among certain characteristics of the descriptions were found.;The typical description made …

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Comparison Of Classification Methods For Perspiration-Based Liveness Algorithm, Sujan T. V. Parthasaradhi Dec 2003

Comparison Of Classification Methods For Perspiration-Based Liveness Algorithm, Sujan T. V. Parthasaradhi

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the modern world there is a need for security. Biometric technologies provide a means for providing this security. Of the many different available biometric technologies, fingerprint recognition is the most popular. As with all security measures, biometric devices may be subject to attacks on the system. Fingerprint scanners may be susceptible to spoofing using artificial materials, or in the worst case, dismembered fingers. Liveness, i.e. to determine whether the introduced biometric is coming from a live source, has been suggested as a means to circumvent attacks that use spoof fingers. It has been shown that water based casting materials …

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Potential Field Theory And Its Applications To Classical Mechanical Problems, Shannon Rae Stillwagon Dec 2003

Potential Field Theory And Its Applications To Classical Mechanical Problems, Shannon Rae Stillwagon

Graduate Theses, Dissertations, and Problem Reports (ETD)

Advances in many scientific fields are expected to come from work in nanotechnology. Engineering at nano-scales presents novel problems that classical mechanics cannot solve. Many engineers are uncomfortable designing at this level because classical or continuum mechanics does not apply and quantum mechanics is said to apply in a tangible way. There are unique opportunities to contribute to the design, controls, and analysis of systems that are particularly suited to mechanical engineering. Within the derivations of classical mechanics are assumptions that limit its use to bulk engineering. These assumptions are examined to determine what principles can be extended to smaller …

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Numerical Analysis Of Source-Water Dynamics For Stream-Bounded Alluvial Aquifers, Sarah E. Webb Dec 2003

Numerical Analysis Of Source-Water Dynamics For Stream-Bounded Alluvial Aquifers, Sarah E. Webb

Graduate Theses, Dissertations, and Problem Reports (ETD)

Alluvial aquifers bounded by streams are water supply sources for numerous communities in the Ohio Valley, West Virginia. Groundwater flow models are tools for estimation of source areas, however, existing analytical solutions apply only in settings involving a single stream boundary. A series of numerical experiments was devised for wells near multiple surface sources examining the controlling aspects of well-location and boundary condition interaction on source areas. Local-scale models were constructed representing an alluvial aquifer bounded by a tributary intersecting a large river. Aquifer behavior was examined in response to variations in pumping well location and tributary gradient. Flow within …

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Model Predictive Control Design For Load Frequency Control Problem, Nedzad Atic Dec 2003

Model Predictive Control Design For Load Frequency Control Problem, Nedzad Atic

Graduate Theses, Dissertations, and Problem Reports (ETD)

Load Frequency Control (LFC) is a mechanism by which power generation and power demand are balanced.;Model Predictive Control (MPC) has been widely accepted as a viable control strategy in the process industry. It is a model based control strategy where an optimization procedure is performed in every sampling interval over a prediction horizon, yielding an optimal control action. The optimization criterion, or objective function, is chosen in such a way as to satisfy the controlled system dynamics and constraints, penalize system output deviation from the desired trajectory, and minimize control efforts. Furthermore, a possibility to incorporate economic objectives into the …

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Adding Liveness Detection To The Hand Geometry Scanner, Musat C. Crihalmeanu Dec 2003

Adding Liveness Detection To The Hand Geometry Scanner, Musat C. Crihalmeanu

Graduate Theses, Dissertations, and Problem Reports (ETD)

In today's dynamic society, the efficiency of the Biometric Systems has an increasing tendency to replace the classic but obsolete keys and passwords. Hand Geometry Readers are popular biometrics used for Access and Control applications. One of their weaknesses is vulnerability to spoofing using fake hands (latex, play-doh or dead-hands).;The objective of this thesis is to design a feature to be added to the Hand Geometry Scanner in order to detect vitality in the hand, reducing spoofing possibilities.;This thesis demonstrates how the Hand Reader was successfully spoofed and shows the implementation of the live detection feature through an inexpensive but …

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Gender Stereotypes In Children's Television Commercials And The Effects On Consumer Purchasing Behavior, Joanne G. Asztalos Dec 2003

Gender Stereotypes In Children's Television Commercials And The Effects On Consumer Purchasing Behavior, Joanne G. Asztalos

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research presents an exploratory investigation on the extent of gender stereotypes portrayed in children's television commercials and the effects on consumer purchasing behavior. The author conducted two studies including a content analysis of viewing 75 children's television commercials, 25 boy, 25 girl, 25 neutral, and documenting evidence of roles, traits, activities, products, speaking parts and settings. Qualitative focus groups were then conducted to correlate the documented gender stereotypes with purchasing behaviors among children between the ages of 6--12. Major findings for this research revealed that there are many gender stereotypes in children's television commercials including the issue that male …

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Real-Time Measurement Of Oxides Of Nitrogen From Heavy-Duty Diesel Engines, Aparna Aravelli Dec 2003

Real-Time Measurement Of Oxides Of Nitrogen From Heavy-Duty Diesel Engines, Aparna Aravelli

Graduate Theses, Dissertations, and Problem Reports (ETD)

New emissions regulations and performance requirements imposed on modern diesel engines encourage the development of improved tools for emissions measurements. This study investigated one of the improved tools for NOx emissions measurement. Objectives of this thesis included measurement, comparison and prediction of NOx emissions from heavy-duty diesel engines using two different NOx analyzers. Steady state and transient tests were conducted on six heavy-duty diesel engines in the WVU Engine and Emissions Research Center (EERC). NOx emissions were measured using a conventional Rosemount NOx analyzer and a Cambustion fast response NOx analyzer. The Rosemount analyzer sampled dilute emissions whereas the fast …

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Generalized Nowhere Zero Flow, Jingjing Chen Dec 2003

Generalized Nowhere Zero Flow, Jingjing Chen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Let G be an undirected graph, A be an (additive) abelian group and A* = A - {lcub}0{rcub}. A graph G is A-connected if G has an orientation D(G) such that for every function b : V(G ) A satisfying Sv∈VG b(v) = 0, there is a function f : E(G) A* such that at each vertex v ∈ V(G), ∂f(v), the net flow out from v, equals b( v). An A-nowhere-zero-flow (abbreviated as A-NZF) in G is a function f : E(G) A* such that at each vertex v ∈ V(G), ∂f(v) = 0.;In this paper, we investigate the …

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Relational Project Modeling And Risk Projection Framework, Brian D. Gould Dec 2003

Relational Project Modeling And Risk Projection Framework, Brian D. Gould

Graduate Theses, Dissertations, and Problem Reports (ETD)

The relational project modeling and risk projection framework enables a projection of the consequences of initial project schedules and schedule changes with respect to risk realization in resource constrained project environments, and the identification of unrecognized schedule risks implied by those schedules.

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Dynamic Response Evaluation Of Fiber-Reinforced Composite Bridge Decks And Bridges, Chandra Sekhar Jinka Dec 2003

Dynamic Response Evaluation Of Fiber-Reinforced Composite Bridge Decks And Bridges, Chandra Sekhar Jinka

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fiber Reinforced Polymer (FRP) composite bridge decks are gaining attention of bridge owners because of their light self weight, corrosion resistance and ease of installation. The lighter weight and lower stiffness of the FRP decks combined with the lower level of damping (than concrete) can lead to excessive deck vibrations and may substantially increase the dynamic amplification of induced stress and deflections. Also, a global NDE technique using dynamic characterization is necessary to ensure the long term performance of FRP bridges. Therefore, an extensive study on FRP decks and FRP bridges is carried out both at laboratory and in the …

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Geologic Feature Prediction Using Roof Bolter Drilling Parameters, Benjamin T. Mirabile Dec 2003

Geologic Feature Prediction Using Roof Bolter Drilling Parameters, Benjamin T. Mirabile

Graduate Theses, Dissertations, and Problem Reports (ETD)

The design of a safe and efficient roof support system is essential for any underground coal mining operation. All underground coal mines in the United States install roof bolts with a roof bolter as the primary means of supporting the mine roof. Proper application of roof bolting is dependent upon knowledge of the mine roof geology.;Recently developed control and data acquisition technologies allow the drilling performance of these roof bolters to be monitored on a real-time basis. Drilling data collected from these machines can be used to determine geological features present in the mine roof. A J. H. Fletcher & …

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Architecture-Level Risk Assessment Tool Based On Uml Specification, Tianjian Wang Dec 2003

Architecture-Level Risk Assessment Tool Based On Uml Specification, Tianjian Wang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Most faults in software systems are likely to be found in only a few of components [1]. The early identification of these components allows the project management to focus on remedial actions, such as redesigning the critical components that are likely to cause field failures or optimally allocating resources on implementation and testing [2]. This thesis presents a prototype tool called Architecture-level Risk Assessment Tool (ARAT) to demonstrate the process of risk assessment. The final result of this process is to distinguish those potentially high risk components in the software system. ARAT is built on the risk assessment methodology [3]. …

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Flow Characterization Of The Ul Smoke Box And Spot-Type Smoke Detectors, Christopher P. Menchini Dec 2003

Flow Characterization Of The Ul Smoke Box And Spot-Type Smoke Detectors, Christopher P. Menchini

Graduate Theses, Dissertations, and Problem Reports (ETD)

The scope of this research involves the first known effort at designing a highly detailed computational fluid dynamics (CFD) model to characterize the flow fields with the UL Smoke Box and a spot type smoke detector within the test section of the smoke box. The proposed CFD model, designed to reflect the same measured conditions in the UL Smoke Box, was developed and validated through experimental velocity data using laser Doppler and hot-wire anemometry. With excellent qualitative comparisons between experimental and computational results, flow characterization using the laminar flow model available in the commercial software package FluentRTM was sufficiently achieved. …

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Finite Element Damage Modeling Of Plain Weave Fabrics, Kaarthik K. Sikkil Dec 2003

Finite Element Damage Modeling Of Plain Weave Fabrics, Kaarthik K. Sikkil

Graduate Theses, Dissertations, and Problem Reports (ETD)

Plain weave fabrics are used as reinforcements in composites in order to obtain improved inter-laminar properties. But these advantages are at the cost of reduced stiffness and strength in the in-plane directions. Therefore, it is important to study the mechanical behavior of such composites. In this work, the geometrical model needed for finite element discretization of the plain weave fabrics are developed for three configurations---single lamina, iso-phase, and out-of-phase. Next, a procedure to determine the longitudinal elastic modulus under tensile loading is presented. Then, a meso level damage model is used for predicting the inelastic tensile behavior of the fabrics. …

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Effect Of Rate Of Sumping On Fragmentation Process In Laboratory Rotary Cutting Simulator, Muralidharan Venkataraman Dec 2003

Effect Of Rate Of Sumping On Fragmentation Process In Laboratory Rotary Cutting Simulator, Muralidharan Venkataraman

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study was done to examine the fragmentation process and to improve sumping. Research has demonstrated that specific energy and specific respirable dust must be kept minimum to produce the optimum parameters of the rock/coal breakage process and to attain maximum sumping. There are three major elements affecting the efficiency of the cutting head namely: (1) Geometry and size of the cutting tool, (2) Geometry of the drum and lacing and arrangements of the tools on the drum and (3) Effect of rate of advance/dynamic impacts. The emphasis is made on the rate of advance utilizing a miniature rotary cutting …

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Standardization Of Test Methods For Property Evaluation Of Frp Bars, Vijay Kumar Tripathi Dec 2003

Standardization Of Test Methods For Property Evaluation Of Frp Bars, Vijay Kumar Tripathi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this research is to verify/modify/develop standardized test methods for evaluating mechanical properties of Fiber Reinforced Polymer (FRP) bars by conducting limited complementary tests to determine/verify their mechanical properties. Both short and long-term tests were conducted as a part of this research. Short-term tests included tension, flexure, shear and bond property evaluations. Long-term tests included evaluation of moisture absorption and flexural tests on aged bars. A total of 229 FRP bars with different fibers (carbon, glass and aramid), varying diameters (# 3 to #8) and surface textures (ribbed, sand-coated, and sand-coated with helical wraps) were tested under this …

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Teachers' Views Of The Impact Of The Good Start, Grow Smart Early Childhood Initiative On Head Start Programs In A Western Maryland Community, Fannie L. Boayue Dec 2003

Teachers' Views Of The Impact Of The Good Start, Grow Smart Early Childhood Initiative On Head Start Programs In A Western Maryland Community, Fannie L. Boayue

Graduate Theses, Dissertations, and Problem Reports (ETD)

As the call for accountability increased, President George W. Bush signed into law the No Child Left Behind Act in January 2002 to reform the Elementary and Secondary Education Act that was reauthorized in 1994. The Good Start, Grow Smart Early Childhood Education Initiative, followed in April 2002. Both of these reform measures have significant implications for school success and achievement of all children in both childcare and public school settings as well as accountability for teachers and administrators.;The purpose of this study was to investigate and analyze the views of Head Start teachers on the impact of the Good …

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Basic Theory And Experimental Approach To Characterize Flow And Fracture Properties Of Fine Powder Bulk Body, Wiratni Wiratni Dec 2003

Basic Theory And Experimental Approach To Characterize Flow And Fracture Properties Of Fine Powder Bulk Body, Wiratni Wiratni

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation comprised two parts, which were Part I for the development of a method to characterize the fine powder flow at ambient temperature and Part II for the application of the method in fine powder aeration at elevated temperature.;The analysis conducted on fine powder aeration in Part I was based on the theory of homogeneously-aerated-expanded (HAE) emulsion phase, which viewed a system of aerated fine powders as a quasi-solid single phase.;The original aeration data from an aeration experiment (gas velocity, pressure drop, and bed height) were transformed into the new variables specifically defined for aerated fine powder (powder strain …

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Analysis Of A Curved Buoyant Jet In An Enclosure Using Les, Allen E. Badeau Jr. Dec 2003

Analysis Of A Curved Buoyant Jet In An Enclosure Using Les, Allen E. Badeau Jr.

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this study is to investigate curved buoyant jets in an enclosure using Large Eddy Simulation (LES) methods with an Implicit Turbulent Model (ITM). To accomplish this goal, a numerical solver was written, named DREAMRTM, which is capable of solving three dimensional, transient flows using an accurate monotonic and non-oscillatory upwinding scheme. The three-dimensional Navier-Stokes equations are solved in Cartesian coordinates, with the control volume approach being implemented on a staggered grid. The numerical scheme uses a fractional time step method, with the overall spatial and temporal accuracy being second order.;In ITM simulations, there is no explicit subgrid-scale …

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Designing A Scalable Dynamic Load -Balancing Algorithm For Pipelined Single Program Multiple Data Applications On A Non-Dedicated Heterogeneous Network Of Workstations, Ashraf Osman Dec 2003

Designing A Scalable Dynamic Load -Balancing Algorithm For Pipelined Single Program Multiple Data Applications On A Non-Dedicated Heterogeneous Network Of Workstations, Ashraf Osman

Graduate Theses, Dissertations, and Problem Reports (ETD)

Dynamic load balancing strategies have been shown to be the most critical part of an efficient implementation of various applications on large distributed computing systems. The need for dynamic load balancing strategies increases when the underlying hardware is a non-dedicated heterogeneous network of workstations (HNOW). This research focuses on the single program multiple data (SPMD) programming model as it has been extensively used in parallel programming for its simplicity and scalability in terms of computational power and memory size.;This dissertation formally defines and addresses the problem of designing a scalable dynamic load-balancing algorithm for pipelined SPMD applications on non-dedicated HNOW. …

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Censusing And Modeling The Dynamics Of A Population Of Eastern Hemlock (Tsuga Canadensis L.) Using Remote Sensing, W. Robert Lamar Dec 2003

Censusing And Modeling The Dynamics Of A Population Of Eastern Hemlock (Tsuga Canadensis L.) Using Remote Sensing, W. Robert Lamar

Graduate Theses, Dissertations, and Problem Reports (ETD)

A population of eastern hemlock (Tsuga canadensis L.) was censused from the ground using traditional field methods and from the air using large scale, high-resolution, aerial imagery in the early spring of 1997, 1998 and 1999. A manual crown survey map of the population, prepared from aerial imagery, was compared to a traditional field census. Over 60% of the individuals measured on the ground were not detected in the aerial census. Tree size, crown density and crown position all played roles in determining a crown's visibility from the air. Nearly all large, upper canopy hemlocks were visible in the aerial …

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Investigation Of Initiation Of Reverse Transcription In Retroviruses Using Vectors With Two Primer -Binding Sites, Yegor A. Voronin Dec 2003

Investigation Of Initiation Of Reverse Transcription In Retroviruses Using Vectors With Two Primer -Binding Sites, Yegor A. Voronin

Graduate Theses, Dissertations, and Problem Reports (ETD)

Initiation of reverse transcription in retroviruses occurs on a specific place in viral genome, called primer-binding site (PBS). Cellular tRNA is annealed to the complementary PBS and is used as a primer. We constructed murine leukemia virus (MLV)-based vectors containing two PBSs, one in normal position and another in the middle of the vector. Green fluorescence protein (GFP) gene was inserted between the two PBSs. The internal PBS was derived from a spleen necrosis virus (SNV), which uses the same tRNA-Pro as a primer. We have shown that the internal PBS was functional for initiation of reverse transcription. Replication of …

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Spline Based Controller For Nonlinear Systems, Ali Karimi Dec 2003

Spline Based Controller For Nonlinear Systems, Ali Karimi

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this thesis is to apply spline theory to implement controllers for nonlinear systems. Two different systems, forced Duffing oscillators and power systems, are investigated. The spline method is used to mimic the controller which drives a state of the Duffing system toward a desired path. The spline-based nonlinear controller has piecewise polynomial segments with different order of polynomials on each segment. Controller efforts for different order of polynomial interpolants and power spectral densities of the controller signals are compared with the exact feedback linearizaton method.;The first objective for power systems is to design nonlinear excitation controllers for …

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Eulerian Subgraphs And Hamiltonicity Of Claw -Free Graphs, Mingquan Zhan Aug 2003

Eulerian Subgraphs And Hamiltonicity Of Claw -Free Graphs, Mingquan Zhan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Let C(l, k) denote the class of 2-edge-connected graphs of order n such that a graph G ∈ C(l, k) if and only if for every edge cut S ⊆ E(G) with |S| ≤ 3, each component of G - S has order at least n-kl . We prove that If G ∈ C(6, 0), then G is supereulerian if and only if G cannot be contracted to K2,3, K 2,5 or K2,3(e), where e ∈ E(K2,3) and K2,3(e) stands for a graph obtained from K2,3 by replacing e by a path of length 2. Previous results by Catlin and …

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Dynamic Modeling And Control Of A Proton Exchange Membrane Fuel Cell As A Distributed Generator, Padmanabhan Srinivasan Aug 2003

Dynamic Modeling And Control Of A Proton Exchange Membrane Fuel Cell As A Distributed Generator, Padmanabhan Srinivasan

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research concentrated on the modeling and control of a Proton Exchange Membrane (PEM) fuel cell in a deregulated electric power system. The PEM fuel cell is a Multiple Input Multiple Output (MIMO) system with various dynamic states. In most previous model studies, the stack temperature of a fuel cell was considered to be constant. For long duration short transient and analysis, the stack temperature should be considered a variable. A derived dynamic model for the PEM fuel cell was analyzed using MATLAB/SIMULINK. Power generation characteristics of the PEM fuel cell were presented. Performance of the PEM fuel cell under …

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Effect Of Computer Practice Of Component Gait Training Facts On Choice Of Ambulation Aid And Gait Pattern By Physical Therapist Assistant Students, Beverly R. Born Aug 2003

Effect Of Computer Practice Of Component Gait Training Facts On Choice Of Ambulation Aid And Gait Pattern By Physical Therapist Assistant Students, Beverly R. Born

Graduate Theses, Dissertations, and Problem Reports (ETD)

Health care educational programs are challenged to provide efficient and effective instructional strategies to teach students both the foundation knowledge and problem solving skills that they need to provide quality health care services. In the present study, computer-based text passages and quizzes were used to teach physical therapist assistant (PTA) students the component facts and principles needed for the higher level skill of choosing ambulation aids and gait patterns for patients in described clinical scenarios. The research questions were (a) whether learning component gait training skills would result in better ability to choose ambulation aids and gait patterns for patients …

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