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Graduate Theses, Dissertations, and Problem Reports (ETD)

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Opportunities And Occupations In Animal And Veterinary Sciences Based On The Current Careers Of West Virginia University Alumni, Stacey Michelle Hawkins Dec 2002

Opportunities And Occupations In Animal And Veterinary Sciences Based On The Current Careers Of West Virginia University Alumni, Stacey Michelle Hawkins

Graduate Theses, Dissertations, and Problem Reports (ETD)

The primary purpose of this study was to examine the career opportunities for graduates completing a Bachelor of Science degree in Animal and Veterinary Sciences at West Virginia University as measured by the first and current careers of alumni. The target population consisted of all alumni that graduated between the years 1991 and 2001. Over 61.6% of the West Virginia University Animal and Veterinary Science graduates were satisfied with both their first career selection as well as their current career. After graduating with a Bachelor of Science degree two-thirds of the graduates decided to pursue a post-graduate degree. Professional careers, …

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Chemical And Physical Properties Of Acid Mine Drainage Floc, Catherine M. Bohan Dec 2002

Chemical And Physical Properties Of Acid Mine Drainage Floc, Catherine M. Bohan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Acid mine drainage is a serious environmental concern in many regions worldwide, but especially in coal and metal mining regions. These acid drainages are often treated with chemicals to raise the pH of the water and to cause neutralization and precipitation of metals. As neutralization occurs, a looser gelatinous material called "floc" is produced. The effects of neutralizing chemical, pH, sulfate to iron molar ratio, and solids concentration on floc settling properties were determined in synthetic acid mine drainage. Sulfate was the important factor affecting floc physicochemical properties, increasing settling times from 25-125% and decreasing settling rates from 24-63%. Neutralization …

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Development Of Lightweight Frp Bridge Deck Designs And Evaluations, Isaac Lem Howard Dec 2002

Development Of Lightweight Frp Bridge Deck Designs And Evaluations, Isaac Lem Howard

Graduate Theses, Dissertations, and Problem Reports (ETD)

The focus of this study was to develop and analyze lightweight FRP bridge decks and determine their adequacy under AASHTO's HS25 loading case with minimum stringer spacings of five feet. Two different multicellular decks were designed and tested during this study. Both decks had fiber volume fractions of approximately 54% and weighed 14--15 lb/ft2 of deck area. Testing was performed to determine both the elastic and failure response at the component level and the elastic response at the system level. Theoretical correlation of stiffness was made via approximate classical lamination theory, and maximum transverse load distribution factors were predicted. In …

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Assessing The Return On Investment For Various Types Of Break-In Training, Kim L. Trenbath Dec 2002

Assessing The Return On Investment For Various Types Of Break-In Training, Kim L. Trenbath

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis presents a Return on Investment, or ROI, model for various types of break-in training by utilizing employee learning curves as a factor of the cost. The model captures the additional profit earned when a company makes an investment in break-in training, training employees receive at the beginning of their employment. Research involves developing employee learning curves for break-in training vs. traditional training through experimentation. The thesis utilizes the improvement in the learning curve as the driving factor behind the profits. The ROI model is a comparison between the profits, or benefits minus cost, of a traditional and break-in …

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Predictors Of Student Success In Distance Education Courses, Rhonda Suzanne Shepperd Dec 2002

Predictors Of Student Success In Distance Education Courses, Rhonda Suzanne Shepperd

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study investigated the relationship between faculty-student communication, student time management, student expectations, and quality of instruction and the level of student success in distance courses. The population of the study consisted of undergraduate students enrolled in Independent Study courses at Mountain State University (N = 1007) during the summer and fall 2001 terms. The sample consisted of 500 students randomly selected from the population. Participants completed the Distance Education Satisfaction Survey developed by the researcher. Data analyses indicated that statistically significant differences existed within faculty-student communication, student time management, student expectations and quality of instruction based on the level …

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Numerical Modeling Of Air Blast Effects On Hybrid Structures, Matthew J. Fox Dec 2002

Numerical Modeling Of Air Blast Effects On Hybrid Structures, Matthew J. Fox

Graduate Theses, Dissertations, and Problem Reports (ETD)

Blast resistant structures are gaining increased need in today's society. This research addresses adding composite reinforcement to existing concrete structures to decrease blast damage. An upgraded material model for concrete is presented. This model, used in LS-DYNA3D, incorporates tensile damage, which allows the concrete to degrade as it is loaded. The concrete model is tested using existing unreinforced and reinforced concrete beam tests. Some beams were plain, others were externally reinforced with composites, bonded to the exterior of the beams. There is a very good correlation between the predicted and existing data. The concrete model was then used to predict …

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Evaluation Of Strut-And-Tie Modeling For Bridge Pier Applications, Thomas Nicholas Ii Dec 2002

Evaluation Of Strut-And-Tie Modeling For Bridge Pier Applications, Thomas Nicholas Ii

Graduate Theses, Dissertations, and Problem Reports (ETD)

Strut-and-tie modeling is an analysis and design tool for reinforced concrete elements which assumes that internal stresses are transferred through a truss type mechanism. The tensile ties and compressive struts serve as truss members connected by nodal zones. The internal truss idealized by the strut-and-tie model implicitly accounts for the distribution of both flexure and shear.;In 1998, the AASHTO LRFD Bridge Specifications (1998) incorporated the strut-and-tie modeling procedure for the analysis and design of deep reinforced concrete members where sectional design approaches are not valid. In most instances, hammerhead piers can be defined as deep reinforced concrete members and therefore, …

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Operating Market Based Regulation Service Using Software Agents Compliant With Nerc's Control Performance Standards, Ramanujam Srinivasan Dec 2002

Operating Market Based Regulation Service Using Software Agents Compliant With Nerc's Control Performance Standards, Ramanujam Srinivasan

Graduate Theses, Dissertations, and Problem Reports (ETD)

With the changing scenario for procurement of energy it becomes necessary to understand the process of obtaining energy from a diverse set of suppliers capable of providing substantial amounts of electric power at competitive prices. Sufficient insight has been gained in the energy brokerage system design and planning owing to experiences in the recently established markets especially the California market. It becomes contextual to analyze and understand the procurement of ancillary services, which are generally bundled as part of the wholesale energy supply chain, using a similarly competitive environment having a number of players that provide electric power for such …

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Mode-I Fatigue Fracture Of Interface For Fiber -Reinforced Polymer Composite Bonded To Wood, Junhui Jia Dec 2002

Mode-I Fatigue Fracture Of Interface For Fiber -Reinforced Polymer Composite Bonded To Wood, Junhui Jia

Graduate Theses, Dissertations, and Problem Reports (ETD)

For applications in civil infrastructure rehabilitation and new construction, wood is being reinforced with externally bonded laminates and fabrics of fiber-reinforced polymer (FRP) composites. The potential benefits of external reinforcement with bonded FRP composites have been demonstrated through several studies, and the field implementation of this technology has been successfully proven in numerous projects. However, there is a concern with the long-term performance of the interface bond, since an inadequate bond strength and integrity can render the reinforcement ineffective and lead to premature failure of the structure. The performance of FRP-wood bonded interfaces under static and environmental loads have been …

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Flight Testing Of A Remotely Piloted Vehicle For Aircraft Parameter Estimation Purposes, Brad A. Seanor Dec 2002

Flight Testing Of A Remotely Piloted Vehicle For Aircraft Parameter Estimation Purposes, Brad A. Seanor

Graduate Theses, Dissertations, and Problem Reports (ETD)

The contribution of this research effort was to show that a reliable RPV could be built, tested, and successfully used for flight testing and parameter estimation purposes, in an academic setting. This was a fundamental step towards the creation of an automated Unmanned Aerial Vehicle (UAV). This research project was divided into four phases. Phase one involved the construction, development, and initial flight of a Remotely Piloted Vehicle (RPV), the West Virginia University (WVU) Boeing 777 (B777) aircraft. This phase included the creation of an onboard instrumentation system to provide aircraft flight data. The objective of the second phase was …

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Glass Reinforcement Of Recycled Polycarbonate, Adam Al-Mulla Dec 2002

Glass Reinforcement Of Recycled Polycarbonate, Adam Al-Mulla

Graduate Theses, Dissertations, and Problem Reports (ETD)

The main barrier to recycling of post-consumer plastics is the commingled nature of these materials with consequent poor and variable mechanical, thermal and flow properties; separating the polymers by chemical type is prohibitively expensive and does not completely solve the problem of batch-to-batch variability in properties that results from variations in the nature and amount of impurities and variation in polymer molecular weight and molecular weight distribution. In the present work, it is proposed that the addition of up to 20 wt% short glass fibers to the mixed plastic makes the mechanical and flow properties of the composite depend more …

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Rubber Toughening Of Glass-Fiber -Reinforced Nylon 66, Fares D. Alsewailem Dec 2002

Rubber Toughening Of Glass-Fiber -Reinforced Nylon 66, Fares D. Alsewailem

Graduate Theses, Dissertations, and Problem Reports (ETD)

Glass fibers are commonly added to thermoplastics by the process of extrusion compounding for a variety of reasons, mainly to enhance their strength and make them dimensionally stable. Since the extruder has to be flushed out each time product composition is changed, a large amount of incompatible polymeric waste is generated. This waste material is usually landfilled even though the polymers contained in it are valuable and worth being recycled. It is the drastic reduction in mechanical properties resulting from polymer incompatibility which restricts their recycling. A good strategy of recycling thermoplastics calls for separating materials from each other before …

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Mode I Fracture And Durability Of The Cfrp -Concrete Interface Bond, David Moses Boyajian Dec 2002

Mode I Fracture And Durability Of The Cfrp -Concrete Interface Bond, David Moses Boyajian

Graduate Theses, Dissertations, and Problem Reports (ETD)

The continual degradation of civil infrastructures worldwide has prompted the need for effective solutions, posing major challenges to those involved with reinforced concrete structures. Externally bonded fiber reinforced polymer (FRP) composites have proven to be an efficient means of rehabilitation and enhancement to both existing and new structures alike. An important issue regarding this technology that needs further exploration, however, is the strength and integrity of the interface bond---the inadequacy of which can result in premature failure of the reinforced member.;Until now, there were no available methods to rigorously evaluate the interface bond strength and integrity for concrete structures externally …

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Using Waterflood Performance To Characterize Flow-Units In A Heterogeneous Reservoir, Vamsi Krishna Alla Dec 2002

Using Waterflood Performance To Characterize Flow-Units In A Heterogeneous Reservoir, Vamsi Krishna Alla

Graduate Theses, Dissertations, and Problem Reports (ETD)

Simulation of waterflood performance is used to verify the characterization of flow-units in a heterogeneous reservoir. BOAST98 software was used for simulation of waterflood performance. Two adjacent five spot patterns in the Stringtown field in West Virginia were selected to be evaluated in this study.;The predicted permeability along with the porosity from Artificial Neural Network (A.N.N) was used for primary characterization purpose and identification of flow-units in the two five spots patterns.;Two alternate simulation models were developed. The simulation model was developed using the available data and those predicted using A.N.N. to verify that the flow-units model was an accurate …

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Evaluations Of Concrete Overlays For Bridge Deck Applications, Shiwei Luo Dec 2002

Evaluations Of Concrete Overlays For Bridge Deck Applications, Shiwei Luo

Graduate Theses, Dissertations, and Problem Reports (ETD)

Protective concrete deck overlays have been successfully used by WVDOH in a number of old and new concrete bridge decks to extend their service life, but in several cases delamination and failures have been observed. A comprehensive study has been recently defined to investigate overlays performance and delamination, culminating eventually in the development of specifications in collaboration with WVDOH and the Contractors and Building Supplies Associations of WV.;The present study is an exploratory research concerned with evaluations of four types of overlays for bridge deck applications, and include: latex modified concrete (LMC), microsilica modified concrete (MMC), microsilica modified concrete with …

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Characterization Of Infield Duty Cycles And Exhaust Emissions From Diesel Powered Off-Road Heavy-Duty Equipment, Jeremiah Christopher Rohrbaugh Dec 2002

Characterization Of Infield Duty Cycles And Exhaust Emissions From Diesel Powered Off-Road Heavy-Duty Equipment, Jeremiah Christopher Rohrbaugh

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of study was to design, develop, and evaluate techniques to measure exhaust emissions from diesel-powered off road equipment. Emissions data was collected from a Komatsu hydraulic excavator and a Caterpillar track-type tractor.;For the excavator, data was logged during in-field operation, and test cycles were created on a dynamometer test bed using this data. For the tractor, on-board emissions measurement equipment collected mass emissions rate data in field.;Vast differences were found between transient and 8-mode brake-specific test results. Transient cycle HC, CO, CO2, NO, and PM emissions were 50%, 65%, 10%, 35%, and 50% lower than 8-Mode results, respectively. …

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Measurement Of Total Hydrocarbon Emissions With Mems Using A Portable Fid And A Novel Exhaust Flow Meter, Jared Gregory Knight Dec 2002

Measurement Of Total Hydrocarbon Emissions With Mems Using A Portable Fid And A Novel Exhaust Flow Meter, Jared Gregory Knight

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this study was to evaluate tools for in-field, on-board engine emissions measurements, namely, a Signal Model 3030PM hydrocarbon analyzer and McCrometer's V-Cone flow meter. The Signal Model 3030PM analyzer uses a heated flame ionizing detection scheme to measure hydrocarbons. The V-Cone is an obstructive, differential pressure flow meter that reshapes the flow profile, therefore conditioning the flow.;The Signal Model 3030PM analyzer was found to perform as well or better than the HC analyzers currently used in the FTP test cell. Besides the portability feature, the Signal Model 3030PM demonstrated better response, being able to capture the high …

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Zinc Pot Bearing Material Wear Rate As A Function Of Contact Pressure And Velocity, James M. Snider Ii Dec 2002

Zinc Pot Bearing Material Wear Rate As A Function Of Contact Pressure And Velocity, James M. Snider Ii

Graduate Theses, Dissertations, and Problem Reports (ETD)

There are currently over 50 galvanizing lines in operation in the United States producing approximately 50 million tons per year of galvanized sheet. Frequently zinc-pot hardware fails which causes production delay, resulting in an economic loss. It takes approximately 3 hours to change the zinc-pot bearings at a downtime cost of {dollar}400/h.;To predict the performance of the submerged bearings, a large number of variables must be considered. These variables include pot chemistry, temperature, line speed and line tension. With these variables it is possible to develop a design guide for sheet mill operators to determine the most cost-effective selection of …

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Application Evaluation Of A Prototype Backscatter Imaging Ldv System (Bils), Preetanshu Pandey Dec 2002

Application Evaluation Of A Prototype Backscatter Imaging Ldv System (Bils), Preetanshu Pandey

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study focuses on the application evaluation of a prototype backscatter imaging LDV system (BILS). This non-intrusive instrument has the ability to record particle images and two-dimensional velocity data simultaneously. A series of validation tests were conducted to verify the operation of the system. These included comparing the velocity of a wire, attached to a rotating disc, with known angular frequency (measured by digistrobe), with that measured by the instrument. The results were found to be in good agreement. The imaging part of BILS was calibrated using a target with known dimensions.;The terminal velocities and particle sizes of near-spherical, Nu-pareil …

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Off-Line Thai Handwriting Recognition In Legal Amount, Watchara Chatwiriya Dec 2002

Off-Line Thai Handwriting Recognition In Legal Amount, Watchara Chatwiriya

Graduate Theses, Dissertations, and Problem Reports (ETD)

Thai handwriting in legal amounts is a challenging problem and a new field in the area of handwriting recognition research. The focus of this thesis is to implement Thai handwriting recognition system. A preliminary data set of Thai handwriting in legal amounts is designed. The samples in the data set are characters and words of the Thai legal amounts and a set of legal amounts phrases collected from a number of native Thai volunteers. At the preprocessing and recognition process, techniques are introduced to improve the characters recognition rates. The characters are divided into two smaller subgroups by their writing …

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Formation And Dissociation Reaction Rates And Relevant Kinetic Behavior Of Propane Gas Hydrate (Pgh), Feng Song Dec 2002

Formation And Dissociation Reaction Rates And Relevant Kinetic Behavior Of Propane Gas Hydrate (Pgh), Feng Song

Graduate Theses, Dissertations, and Problem Reports (ETD)

The formation and dissociation reaction rates and their kinetic behavior of propane gas hydrate (PGH) within the well-defined sediment particle's packing structures were experimentally investigated in this work by using a multi-phase heterogeneous reaction system, consisting of propane gas (g), water (l), PGH (s) and sediment particles (glass beads) (s). This work was carried out under the formation conditions of P = 0.427 MPa and T = 273.5 K, and under the dissociation conditions of P ≤ 0.168 MPa and T = 273.5 K.;A new designed, isothermal, and packed bed batch reactor was used for the kinetic analysis of the …

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Automation Of The Superpave Mix Design Process For The West Virginia Division Of Highways, Martin Felix Padula Dec 2002

Automation Of The Superpave Mix Design Process For The West Virginia Division Of Highways, Martin Felix Padula

Graduate Theses, Dissertations, and Problem Reports (ETD)

During the fifty years between 1940 and 1990, the nation's bituminous roadways were predominantly designed using either the Marshall or Hveem method. The Superior Performing Asphalt Pavements (Superpave)(TM) method was later developed to address the issues of increased traffic volumes and heavier loads on the nation's roadways. This new mix design process relies on volumetric calculations and graphs, which are cumbersome to perform by hand. There is no current public domain Superpave software package available which is independent of any commercial laboratory product and available to an asphalt mix designer. A component of this research project consisted of creating a …

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Early Component-Based Reliability Assessment Using Uml Based Software Models, William Black Smith V Dec 2002

Early Component-Based Reliability Assessment Using Uml Based Software Models, William Black Smith V

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the last decade, software has grown in complexity and size, while development timelines have diminished. As a result, component-based software engineering is becoming routine. Component-based software reliability assessment combines the architecture of the system with the reliability of the components to obtain the system reliability. This allows developers to produce a reliable system and testers to focus on the vulnerable areas.;This thesis discusses a tool developed to implement the methodology previously created for early reliability assessment of component-based systems. The tool, Early Component-based Reliability Assessment (ECRA), uses Rational Rose Unified Modeling Language (UML) diagrams to predict the reliability of …

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Aerodynamic Drag Reduction Of A Racing Motorcycle Through Vortex Generation, Gerald M. Angle Ii Dec 2002

Aerodynamic Drag Reduction Of A Racing Motorcycle Through Vortex Generation, Gerald M. Angle Ii

Graduate Theses, Dissertations, and Problem Reports (ETD)

The aerodynamic drag of a racing-class motorcycle can be accomplished through either an overall redesign of the surfaces or through some type of flow control mechanism. Due to limitations on the size of the exterior shape the flow control techniques are more practical. Small metal vanes, known as vortex generators were used in this research to mix higher energy freestream air with the lower energy boundary layer, delaying boundary layer growth and separation. In testing performed in the West Virginia University Closed Loop Wind Tunnel a maximum reduction of 118 drag counts (10.1%) was measured. Due to an abnormally high …

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Mechanical Characterization Of Aged Recycled Polymers And Applications, Jose Ricardo Basto Dec 2002

Mechanical Characterization Of Aged Recycled Polymers And Applications, Jose Ricardo Basto

Graduate Theses, Dissertations, and Problem Reports (ETD)

The research focuses on the evaluation of mechanical properties (tension, bending, compression, impact, hardness and creep) of recycled acrylonitrile butadiene styrene (ABS) and polycarbonate (PC) thermoplastics obtained as electronic shredder residue (ESR) from computer housings. Three forms of polymers, i.e., virgin, blend of virgin and recycled, and 100% recycled were investigated to establish their long term mechanical properties. Chopped and continuous glass fiber/fabric addition to the resins was evaluated to study the thermo-mechanical properties.;Mechanical characterization was carried out at freeze-thaw cycling aging. It was found that recycled polymers retain at least 70% of their tensile, bending and compressive strength after …

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Gasmak2 Model For Longwall Gob Gas Emission, Qinghua Jin Dec 2002

Gasmak2 Model For Longwall Gob Gas Emission, Qinghua Jin

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis discusses the development and improvement of an empirical model---GASMAK2, that describes methane control requirements for the longwalling coal in gassy areas. This is not a theoretical model; it uses an empirically determined gas emission rate as an input. The computer program divides Longwall panels into segments, keeps track of the face advance and generates emission rates and volumes for both the entire panel and for individual zones within the panel. This model is Windows-based, uses the full capabilities of the Windows environment to provide a user-friendly program, and can aid in the determination of the number, size and …

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Enhanced Controls For Oxy-Fuel-Fired Batch Tank During Glass Working Period, Ranjit Menon Unnikrishnan Dec 2002

Enhanced Controls For Oxy-Fuel-Fired Batch Tank During Glass Working Period, Ranjit Menon Unnikrishnan

Graduate Theses, Dissertations, and Problem Reports (ETD)

One of the most dynamic developments in the glass industry has been the use of oxy-fuel combustion for melting glass. This new technology has not only increased the energy efficiency of the glass industry, but also has reduced its environmental impacts.;A model has been developed to take into account the effect of pulling the glass for nine hours during the working period on the reduced amount of fuel required for the batch tank, as well as the resulting transients.;The two primary goals of this thesis were to develop a transient transfer function for the batch tank and to develop an …

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Quantifying The Impact Of The Wto On Kuwait, Reyadh Y. Faras Dec 2002

Quantifying The Impact Of The Wto On Kuwait, Reyadh Y. Faras

Graduate Theses, Dissertations, and Problem Reports (ETD)

The major contribution of this study is to quantify the economic impact of Kuwait's membership in the World Trade Organization (WTO) on supply, demand, welfare and terms of trade. A general equilibrium international trade model is used to obtain quantitative results. The model is theoretically static and based on the assumptions of perfect competition and constant returns to scale. However, it was estimated and simulated dynamically.;After specifying the model theoretically it is estimated empirically by linearizing the supply and demand equations that were obtained from solving the model analytically. The estimated model is used in a number of simulation exercises …

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Telecommunications For A Deregulated Power Industry, Biju Naduvathuparambil Aug 2002

Telecommunications For A Deregulated Power Industry, Biju Naduvathuparambil

Graduate Theses, Dissertations, and Problem Reports (ETD)

Telecommunication plays a very important role in the effective monitoring and control of the power grid. Deregulation of the US power industry has enabled utilities to explore various communication options and advanced technologies. Utilities are increasingly investing in distributed resources, dynamic real-time monitoring, automated meter reading, and value added services like home energy management systems and broadband access for its customers. Telecommunication options like power line communications (PLC) and satellites are fast replacing legacy telephone and microwave systems in the US.;The objective of this thesis is to study the communication options that are available for utilities today. Phasor measurement units …

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Intercropping With Resistant Cultivars Reduces Early Blight And Root Knot Disease On Susceptible Cultivars Of Tomato (Lycopersicon Esculentum), Linley Joy Smith Aug 2002

Intercropping With Resistant Cultivars Reduces Early Blight And Root Knot Disease On Susceptible Cultivars Of Tomato (Lycopersicon Esculentum), Linley Joy Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this research was to determine if disease on susceptible tomato cultivars is reduced by intercropping with resistant cultivars. A second objective was to investigate the mechanism of the disease reduction observed. Early blight (caused by Alternaria solani) rate of disease increase and lesion expansion were lower on susceptible tomato cv. 'Brandywine' when intercropped with resistant cv. 'Juliet' than with 'Brandywine' monoculture in both the field and greenhouse. Yield from 'Brandywine' plants was 17.3% greater when intercropped with 'Juliet' than when grown in monoculture. Reduction in lesion expansion on 'Brandywine' when intercropped with 'Juliet' suggests an interaction initiating …

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