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Modeling Of Soil Phosphorus Sorption And Control Of Phosphorus Pollution With Acid Mine Drainage Floc, Bharpoor Singh Sekhon Aug 2002

Modeling Of Soil Phosphorus Sorption And Control Of Phosphorus Pollution With Acid Mine Drainage Floc, Bharpoor Singh Sekhon

Graduate Theses, Dissertations, and Problem Reports (ETD)

The study was conducted to investigate and model phosphorus sorption in soils and to study the effectiveness of acid mine drainage (AMD) floc in controlling phosphorus (P) loss to surface runoff from soils. Phosphorus sorption capacity of surface and subsurface horizons of four benchmark soil series - Berks, Huntington, Lindside, and Monongahela - of West Virginia was measured. The soils of these four series were loaded with increasing amounts of P up to 60% of their P retention capacity. Though amount of P released to the solution increased with increase in degree of P saturation, most of the soils did …

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Electrical Impedance Of Methane Flat Flame, Jeffrey William Rinker May 2002

Electrical Impedance Of Methane Flat Flame, Jeffrey William Rinker

Graduate Theses, Dissertations, and Problem Reports (ETD)

As part of an ongoing effort to improve emissions and increase efficiency of natural gas fired turbines, this work was undertaken to determine if electrical impedance measurements of the flame are a direct indication of fuel/air ratio. Previous worked measured electrical resistance of the combustion of gases in an atmospheric combustor. From this work, it was conjectured that the complex impedance might provide more information about the flame than using pure resistance. This thesis discusses the measurement of the complex electrical impedance of a Methane Flat Flame Burner. The data shows a relationship between the magnitude of the impedance and …

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Otherworldly Goods, Grant Johnson May 2002

Otherworldly Goods, Grant Johnson

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis presents "democratic" art. As defined by the author, democratic art is work that does not bear the idiosyncratic mark of the artist's hand. It is hoped that such work remains more fully open to the viewer's imaginative involvement than work that bears a more overt trace of authorship. As an invitation to such involvement, and in addition to removing the mark of the hand, the artist also creates interactive pieces, such as large-scale slide puzzles, which can be manipulated by the viewer. With these pieces the viewer can re-organize the composition of the work and thereby take as …

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Impact Of Student Teaching Experiences, Personal Demographics, And Selected Factors On The Decisions Of Pre-Service Agricultural Education Teachers To Enter Into Teaching, Gene Allen Hovatter May 2002

Impact Of Student Teaching Experiences, Personal Demographics, And Selected Factors On The Decisions Of Pre-Service Agricultural Education Teachers To Enter Into Teaching, Gene Allen Hovatter

Graduate Theses, Dissertations, and Problem Reports (ETD)

With numerous openings in the agricultural education field and shortages constantly occurring, a common question is asked, "Why are pre-service teachers not teaching?". This study sought to help answer this question by investigating the impact of the student teaching experience upon certified agricultural education graduates. In addition to the student teaching experience, personal demographics and selected factors were investigated to add insight into the problem of pre-service agricultural education teachers not teaching. A two-phase descriptive survey methodology was implemented to collect data from the population, which consisted of 75 pre-service agricultural education students from Delaware Valley College, Pennsylvania State University, …

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How Farmers In West Virginia Are Using Value-Added Processing To Increase Annual Income, Jennifer Leigh Lewis May 2002

How Farmers In West Virginia Are Using Value-Added Processing To Increase Annual Income, Jennifer Leigh Lewis

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to describe methods of value-added processing being employed by farmers in West Virginia, the amount of interest in value-added processing as expressed by agriculture extension agents and farmers, and identified the number of value-added producers in West Virginia. The population targeted with the initial survey consisted of 28 agriculture extension agents in West Virginia representing 55 counties. The second telephone survey was directed to value-added producers within the state. From this data, four farms, Thistledew Farm, Kelly Smith, Headwater Farms and Higson's Farm, were chosen to participate in case studies. Value-added producers were identified …

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Retention Of Early Pregnancy And Its Relationship To Serum Progesterone In Dairy Cattle, Melanie J. Starbuck May 2002

Retention Of Early Pregnancy And Its Relationship To Serum Progesterone In Dairy Cattle, Melanie J. Starbuck

Graduate Theses, Dissertations, and Problem Reports (ETD)

Factors affecting pregnancy maintenance between 28 and 67 days of gestation were studied in dairy cows (N = 211). Beginning on day 28 to 37 post breeding, cows were examined by ultrasonography for a viable pregnancy. Pregnant cows were re-examined for pregnancy losses during the late embryonic (≤day 45) and early fetal stages up to day 67. Overall pregnancy loss was 11%, mostly occurring before day 45. Cows with two corpora lutea maintained fewer pregnancies than cows with one corpus luteum. Pregnancy retention was less when concentrations of progesterone were low during days 28 to 37. The embryo apparently died …

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Doping And Electron-Stimulated Desorption Of Zinc Selenide Grown By Molecular Beam Epitaxy, Brenda L. Vanmil May 2002

Doping And Electron-Stimulated Desorption Of Zinc Selenide Grown By Molecular Beam Epitaxy, Brenda L. Vanmil

Graduate Theses, Dissertations, and Problem Reports (ETD)

Electron irradiation affects ZnSe and ZnMgSe during growth by molecular beam epitaxy. Se desorption rates under electron irradiation are significantly larger than thermal desorption rates. Electron irradiation decreases ZnSe growth rates under Zn-stable conditions, which can be suppressed by Se-stable conditions or use of (211)B oriented substrates. Electron irradiation does not alter composition during ZnMgSe growth.;Chlorine-doped ZnSe and ZnMgSe layers were grown to investigate solubility, native defects and chlorine-impurity-related defects. Cl was electrically active for levels up to 1 x 1019 cm-3 with compensation occurring beyond this point. Compensation appeared coupled to reduced growth rates for higher chlorine fluxes. Cl …

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Relationship Between Maternal Prenatal Vitamin Use And Infant Iron Status, Jennie Pringle Wilkins May 2002

Relationship Between Maternal Prenatal Vitamin Use And Infant Iron Status, Jennie Pringle Wilkins

Graduate Theses, Dissertations, and Problem Reports (ETD)

Subjects were fifty-six women and their infants who were between the ages of six months and twenty-four months. They were clients of Special Supplemental Nutrition Program for Women Infants and Children (WIC) clinics. The WIC clinics were in the West Virginia counties of Ritchie, Gilmer, Calhoun, Braxton, Mason, Jackson, Pleasants, and Greenbrier where the anemia rates were greater than 10%.;Information concerning WIC participation, prenatal vitamin use, history of breast feeding, infant birth weight, and pre-term delivery were obtained through questionnaires. Infants' serum ferritin level was obtained through venous blood and analyzed.;This ex post facto study found no significant result in …

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Design, Construction And Testing Of An Innovative Mechanism For Manual Wheelchair Propulsion, Thomas S. Burke Jr. May 2002

Design, Construction And Testing Of An Innovative Mechanism For Manual Wheelchair Propulsion, Thomas S. Burke Jr.

Graduate Theses, Dissertations, and Problem Reports (ETD)

The concern for people with disabilities who are users of wheelchairs has become a dynamic research area in the past several years. As part of this research, new and innovative mechanisms that give the manual wheelchair users a mechanical advantage, and allow them to operate a standard wheelchair with less effort and muscle strain are being developed.;An innovative mechanism has been conceived, designed, built, and tested. It allows the user to propel a standard wheelchair in both the push and pull strokes of the handle. This new design will allow for a more symmetric muscle development of the shoulder and …

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Expansion Of The Scope Of The Allenic Pauson-Khand Reaction To Include Carboxylic Acids And Esters, Kimberly D. Fisher May 2002

Expansion Of The Scope Of The Allenic Pauson-Khand Reaction To Include Carboxylic Acids And Esters, Kimberly D. Fisher

Graduate Theses, Dissertations, and Problem Reports (ETD)

1,3,3 Trisubstituted allenes were prepared by performing an SN2' reaction of lactones. Opening of the lactone created carboxylic acids that could then be converted to esters. By varing the functionality on the lactone and the Grignard reagents, a variety of allenes could be prepared to test the viability of the Pauson-Khand reaction in the presence of these functional groups. The positioning of the groups also lead to variations in the system. These reactions produced three different types of adducts. They include alpha-methylene cyclopentenones, 4-alkylidene cyclopentenones, and cross conjugated trienes.*.;*Please refer to dissertation for diagrams.

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Modeling Trade And Environmental Interactions, Haixiao Huang May 2002

Modeling Trade And Environmental Interactions, Haixiao Huang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Interactions between trade and the environment have been studied extensively as a reaction to the pressure that the accelerated pace of globalization is placing on environment and trade. Distinguishing itself from previous studies, this research addresses issues, methods and policy implications concerning the interrelationship between trade and environment first in a comprehensive literature survey, and then focuses on a modeling analysis on the interactions between trade and the environment in China.;The literature review provides a perspective on received and future research by employing a dual approach: not only are major issues concerning trade and environment analyzed, but also progress in …

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Depression And Self -Silencing In Lesbian And Heterosexual Women, Samantha Ann Kirk May 2002

Depression And Self -Silencing In Lesbian And Heterosexual Women, Samantha Ann Kirk

Graduate Theses, Dissertations, and Problem Reports (ETD)

Depression among lesbians is an underexplored area in the literature of the psychology of women and in depression research. A few investigators have hypothesized about the factors that place lesbians at risk for depression, and have explored those hypotheses experimentally. However, there is a large gap in the understanding of lesbians and depression. Dana Jack (1991) proposed a model of depression which holds that women who fail to represent their experiences to romantic partners are at increased risk for depression. One hundred and seventy participants were recruited to test this model (85 lesbians and 71 heterosexual women, as well as …

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Slow Wave Ion Heating And Parametric Instabilities In The Helix Helicon Source, John L. Kline May 2002

Slow Wave Ion Heating And Parametric Instabilities In The Helix Helicon Source, John L. Kline

Graduate Theses, Dissertations, and Problem Reports (ETD)

The primary focus of the experiments described here is to determine the mechanism responsible for intrinsic ion heating in helicon sources. Two possible mechanisms have been identified: ion Landau damping of the slow wave and parametrically driven instabilities. Consistent with ion Landau damping of the slow wave, the perpendicular ion temperatures 35 cm downstream of the RF antenna are largest when the RF frequency matches the local lower hybrid frequency; the condition at which the slow wave has a maximum in perpendicular wave number (perpendicular with respect to the applied magnetic field) due to a lower hybrid resonance. The ion …

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Appalachian Diabetes Patients' Preferences For Mental Health Treatment, Sameep Dilip Maniar May 2002

Appalachian Diabetes Patients' Preferences For Mental Health Treatment, Sameep Dilip Maniar

Graduate Theses, Dissertations, and Problem Reports (ETD)

Although psychologists are beginning to be employed in medical settings, little is known about medical patients' preferences when encountering mental health problems. One population that could be better served by this type of research is diabetes mellitus because of the poor adherence rates and high depression associated with the disease. The current study aimed to identify diabetes patients' preferences for treatments and helpers when encountering emotional difficulties. Data were collected on 80 patients from an Appalachian region of the United States who had previously been diagnosed with either type 1 or type 2 diabetes. Results indicated that diabetes patients were …

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Whitney Preserving Maps, Benjamin Espinoza May 2002

Whitney Preserving Maps, Benjamin Espinoza

Graduate Theses, Dissertations, and Problem Reports (ETD)

We connect Whitney levels and continuous functions between continua to obtain the new notion of Whitney preserving maps. We introduce the basic properties of Whitney preserving maps. We give conditions on a continuum X in order that a Whitney preserving map f from X to the unit interval is a homeomorphism, and we give examples to show the conditions are necessary and that the result is false when the range of the map is the unit circle. Concerning the structure of any continuum X, we show that if A is a continuous decomposition of X into nondegenerate terminal continua, then …

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Instructional Alternative For Underprepared Students, Deborah A. Thomas May 2002

Instructional Alternative For Underprepared Students, Deborah A. Thomas

Graduate Theses, Dissertations, and Problem Reports (ETD)

This quasi-experimental study examined the use of daily drills as a supplemental instructional alternative for underprepared students enrolled in General Psychology courses at a midwestern open-admission community college. Underprepared students were defined as those students whose Nelson-Denny Reading Test score fell below community college entrance level criteria. Daily one-minute drills of course content were provided to all participants in the experimental group. Lectures, discussion, and class activities were provided to both groups. The experimental and control group were compared using retention data, reading scores, and exam scores. Although more students in the experimental group withdrew from the course, most withdrew …

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Small Cycle Cover, Group Coloring With Related Problems, Xiangwen Li May 2002

Small Cycle Cover, Group Coloring With Related Problems, Xiangwen Li

Graduate Theses, Dissertations, and Problem Reports (ETD)

Bondy conjectured that if G is a simple 2-connected graph with n ≥ 3 vertices, then the edges of G can be covered by at most 2n-33 cycles. In Chapter 2, a result on small cycle cover is obtained and we also show that the result is as best as possible.;Thomassen conjectured that every 4-connected line graph is hamiltonian. In Chapters 3 and 4, we apply Catlin's reduction method to study cycles in line graphs. Results about hamiltonian connectivity of line graphs and 3-edge-connected graphs are obtained. Several former results are extended.;Jaeger, Linial, Payan and Tarsi introduced group coloring in …

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Analysis And Robust Decentralized Control Of Power Systems Using Facts Devices, Karl E. Schoder May 2002

Analysis And Robust Decentralized Control Of Power Systems Using Facts Devices, Karl E. Schoder

Graduate Theses, Dissertations, and Problem Reports (ETD)

Today's changing electric power systems create a growing need for flexible, reliable, fast responding, and accurate answers to questions of analysis, simulation, and design in the fields of electric power generation, transmission, distribution, and consumption. The Flexible Alternating Current Transmission Systems (FACTS) technology program utilizes power electronics components to replace conventional mechanical elements yielding increased flexibility in controlling the electric power system. Benefits include decreased response times and improved overall dynamic system behavior. FACTS devices allow the design of new control strategies, e.g., independent control of active and reactive power flows, which were not realizable a decade ago. However, FACTS …

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Design And Implementation Of Web-Based Gis For Forest Fragmentation Analysis, Fei Wang May 2002

Design And Implementation Of Web-Based Gis For Forest Fragmentation Analysis, Fei Wang

Graduate Theses, Dissertations, and Problem Reports (ETD)

The advantages and limitations of current web GIS software for forest fragmentation information and analysis functionality were investigated using Landsat Thematic Mapper data of 1987 to 1999 for a test site in northern West Virginia. ESRI's ArcIMS technology was used to build a Web-based forest fragmentation analysis system to query, represent, and analyze the status of forest fragmentation using landscape metrics. Both ArcIMS HTML and Java fragmentation analysis tools were constructed. The web GIS was evaluated with respect to accessibility, navigation, interactive cartographic functionality, and spatial analysis functionality. The current ArcIMS approach was found to offer only limited support for …

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Combustion Analysis And Particulate Mutagenicity Characterization For A Single-Cylinder Diesel Engine Fueled By Fischer -Tropsch Derived Liquids, Michael Hayden Mcmillian May 2002

Combustion Analysis And Particulate Mutagenicity Characterization For A Single-Cylinder Diesel Engine Fueled By Fischer -Tropsch Derived Liquids, Michael Hayden Mcmillian

Graduate Theses, Dissertations, and Problem Reports (ETD)

Further growth of diesel engines in the light-duty and heavy-duty vehicular markets is closely linked to the potential health risks of diesel exhaust. Cleaner burning fuels, such as those derived from natural gas via the Fischer-Tropsch (FT) process, offer a potentially economically viable alternative to standard diesel fuel. As part of this study, a two-liter, single-cylinder, four-stroke direct-injected engine was instrumented for in-cylinder pressure measurements. The emissions and performance data from engine operation with Federal low sulfur No. 2 diesel fuel (DF) and natural gas derived FT fuel were compared. Also as part of the study, an investigation was carried …

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Parameter Identification Of Induction Motor Using A Genetic Algorithm, Edina Bajrektarevic May 2002

Parameter Identification Of Induction Motor Using A Genetic Algorithm, Edina Bajrektarevic

Graduate Theses, Dissertations, and Problem Reports (ETD)

High performance variable-speed machines incorporate a model for the system in either the controller or state estimation stages. The accuracy and general robustness of the machine is dependant on this model. Therefore, it must accurately represent both the electrical and electromagnetic interactions within the machine and associated mechanical systems. Recently, some new technologies have been tested in the field of electromechanics like neural networks, fuzzy logic, simulated annealing and genetic algorithms. These methods are increasingly being utilized in solving electric machine problems.;In this thesis, a genetic algorithm (GA)---a form of artificial intelligence---is employed to identify the electric parameters of induction …

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Nondestructive Evaluation Of Frp Composite Members Using Infrared Thermography, Gurudutt Sundara Ram Bangalore May 2002

Nondestructive Evaluation Of Frp Composite Members Using Infrared Thermography, Gurudutt Sundara Ram Bangalore

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this research is to establish infrared thermography as an effective tool for nondestructive evaluation of structural members made of fiber reinforced polymer (FRP) composite materials. The applicability of this method for the detection of subsurface anomalies such as voids, cracks, debonding, and delaminations in concrete bridge decks and pavements and in some configurations of FRP decks has been studied earlier by other researchers. These earlier studies have yielded reasonably satisfactory results though further refinement of the methodology and improvements in the image processing techniques were recommended.;To enhance the effectiveness of the infrared thermography technique, it is important …

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Manufacture And Rehabilitation Of Guardrail Posts Using Composite Fabrics, Ram Chamarthy May 2002

Manufacture And Rehabilitation Of Guardrail Posts Using Composite Fabrics, Ram Chamarthy

Graduate Theses, Dissertations, and Problem Reports (ETD)

The West Virginia Department of Transportation (WVDOT) uses approximately 50,000 wood and 200,000 steel guardrail posts on an annual basis. The need to develop guardrail posts made of a different material is motivated by the high cost of steel, along with the greater difficulty associated with driving large diameter wood posts.;The primary objective of this study was to develop a Glass Fiber Reinforced Polymer (GFRP) wood post that is more cost effective than a steel post and has smaller diameter than a conventional wood post. Another objective was to develop a portable fabric-wrapping machine for field applications.;Unwrapped and GFRP wrapped …

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Establishing Design Vehicles For The Hang-Up Problem, Amy Lorraine Clawson May 2002

Establishing Design Vehicles For The Hang-Up Problem, Amy Lorraine Clawson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Current design vehicles do not address the hang-up problem. Two factors affect hang-ups: vehicle geometry and roadway geometry. There is a need to establish design vehicle characteristics for hang-up prone vehicles to reduce hang-ups potential.;Roadway geometry and vehicle characteristics relative to the hang-up problem were reviewed. Consideration of these properties by key organizations and associations, and government regulations were studied, and research performed by individuals establishing other design vehicles were analyzed. A general methodology was established.;When choosing design vehicles for the vehicle population, variation in vehicle population, the ramifications of using a limited number of vehicles, and local conditions were …

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Use Of West Virginia Permanent Traffic Recorder Data To Develop Factors For Traffic And Truck Variation, Jacob Scott D'Angelo May 2002

Use Of West Virginia Permanent Traffic Recorder Data To Develop Factors For Traffic And Truck Variation, Jacob Scott D'Angelo

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to use data collected from the 52 permanent count stations located throughout the state to develop four sets of factors that would assist the West Virginia Department of Transportation (WVDOT) in the management and engineering of the roadways in West Virginia.;The objectives of this study were to: (1) Establish correction factors that can be applied to the short-term single pneumatic tube traffic count stations to adjust for the effect of three or more axle trucks on the volume counts. (2) Establish factors that use the peak hour volume (PHV) to estimate the design hour …

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Pulse Charging Lead-Acid Batteries To Improve Performance And Reverse The Effects Of Sulfation, Robert B. Cooper May 2002

Pulse Charging Lead-Acid Batteries To Improve Performance And Reverse The Effects Of Sulfation, Robert B. Cooper

Graduate Theses, Dissertations, and Problem Reports (ETD)

When lead-acid batteries are improperly charged or discharged, useful power delivered to loads diminishes. One cause for this is a phenomenon generally referred to as sulfation. One possible method that has been proposed by many to reverse the effects of sulfation is to recharge the lead-acid battery using a pulse charger. To gain a better understanding of the possible benefits of this type of charging, a pulse charger/discharger was constructed. Cycle testing was then done on six pairs of batteries to compare the pulse charged batteries to conventional full-wave rectifier charged batteries. The results of the tests showed that pulse …

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West Virginia University Ceramic Arts Production Studio Program, Jeffrey Stewart Greenham May 2002

West Virginia University Ceramic Arts Production Studio Program, Jeffrey Stewart Greenham

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis is an analysis of West Virginia University's ceramic arts production techniques program, its educational impact, and historical importance.

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Comparison Of 19mm Superpave And Marshall Base Ii Mixes In West Virginia, Vasavi Kanneganti May 2002

Comparison Of 19mm Superpave And Marshall Base Ii Mixes In West Virginia, Vasavi Kanneganti

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Superior Performing Asphalt Pavements (Superpave(TM)) asphalt concrete mix design method was developed through Strategic Highway Program (SHRP) in 1993. With the introduction of Superpave mix design, the Marshall method of mix design is becoming obsolete for highway pavements. Superpave implementation varies by state. The WVDOH has implemented Superpave on all National Highway System projects since 1997. The decision regarding implementation of Superpave for low volume roads in WV is still under review.;The primary objective of this research work was to compare the 19mm Superpave and Base II Marshall design mixes in WV to supplement information required for WVDOH to …

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Degree Sequences, Rong Luo May 2002

Degree Sequences, Rong Luo

Graduate Theses, Dissertations, and Problem Reports (ETD)

A nonincreasing sequence pi = (d1, d2,···,dn) of nonnegative integers is said to be graphic if it is the degree sequence of a simple graph of order n and such graph is referred to as a realization of pi.;Let H be a simple graph. A graphic sequence pi is said to be potentially H-graphic if it has a realization G containing H as its subgraph.;In this paper, we characterize the potentially Ck graphic sequence for k = 3, 4, 5. These characterizations imply theorems due to P. Erdos, M. S. Jacobson and J. Lehel, R. J. Gould, M. S. Jacobson …

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Random Search Of And-Or Graphs Representing Finite-State Models, David Robert Owen May 2002

Random Search Of And-Or Graphs Representing Finite-State Models, David Robert Owen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Model checking tools have been effective in testing concurrent software represented by communicating finite-state machines. But these tools may require a very large amount of memory. A finite-state model can be translated automatically into a compact AND-OR graph. We use an abductive random search scheme to extract, from the AND-OR graph, information about the execution of the program represented by the original finite-state model.;We use the search to measure testability. For AND-OR graphs representing highly testable programs, we find quickly everything it is possible to find; that is, if the number of unique goals found is plotted, we see a …

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