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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

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 …


Characterization Of In-Use Emissions From On-Highway Heavy-Duty Diesel Engines, Mohan Krishnamurthy Dec 2003

Characterization Of In-Use Emissions From On-Highway Heavy-Duty Diesel Engines, Mohan Krishnamurthy

Graduate Theses, Dissertations, and Problem Reports

Class-8 trucks with GVWR of 80,000 lbs were tested on different driving routes and in-use brake-specific emissions of NOx and CO2 data were collected using the West Virginia University's Mobile Emissions Measurement System (MEMS). An uncertainty analysis was performed on the MEMS and it was determined the maximum possible error in the measurement of brake-specific emissions of NOx was 8% and CO2 was 6%.;A modal analysis indicated that the cruise mode comprised 70% of the time that the vehicle spent in the Not-to-Exceed (NTE) zone while the acceleration and deceleration modes about 20% and 10% respectively.;In order to reduce the …


Fatigue Response Of Fabric Reinforced Polymeric Composites, Venkatakrishnan Natarajan Dec 2003

Fatigue Response Of Fabric Reinforced Polymeric Composites, Venkatakrishnan Natarajan

Graduate Theses, Dissertations, and Problem Reports

Fiber Reinforced Polymeric (FRP) Bridge decks have been an active area of research for the past 10 yrs. In order to better understand the long term efficiency and reliability of FRP bridge decks, and to develop design and test specifications, laboratory testing and characterization of the deck systems and the FRP material, is necessary. Majority of the FRP deck systems available to date are made of glass-reinforcing fibers in the form of fabrics, mats, rovings, etc. Currently, the fatigue response of multidirectional composite is not readily available in the literature and much work needs to be done to understand the …


Characterization Of New Particulate Mmc Materials And Bolted Joints Through Applicable Astm Standards, Vinu Zacharia Mathew Dec 2003

Characterization Of New Particulate Mmc Materials And Bolted Joints Through Applicable Astm Standards, Vinu Zacharia Mathew

Graduate Theses, Dissertations, and Problem Reports

Particulate reinforced metal matrix composites (PRMMC) comprise a new class of materials whose properties can be adjusted to suit a particular application. The main purpose of producing PRMMC is to achieve lightweight materials with added properties like high stiffness, high ultimate strength and hardness.;In this study we deal with PRMMC manufactured by a novel technology involving the pressure less infiltration of aluminum into a mass of ceramic reinforcement particles. Basic tests like tension test, three point bending test, hardness tests and coefficient of thermal expansion are conducted according to the ASTM standards in order to characterize the material. All these …


Long-Term Performance Of Pot Hardware In Continuous Galvanizing Lines, Venkatesh Parthasarathy Dec 2003

Long-Term Performance Of Pot Hardware In Continuous Galvanizing Lines, Venkatesh Parthasarathy

Graduate Theses, Dissertations, and Problem Reports

Preliminary comparative wearing tests were conducted on wearguard bearing system against CF3M (casting version of 316L steel), with tungsten carbide laser clad coating, at 30% and 50% production line tension. Tests were also conducted on Stellite 6 against Tribaloy T 400 at 50% production line tension. For each test, periodic measurements of wearing rate, surface microstructure and surface hardness were carried out. An unique dross build-up setup which consists of two sleeves counter rotating against each other was designed to simulate the dross build-up in production line. The chemical composition of the dross material formed and change in sleeve microstructures …


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

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. …


Alkaline Durability Tests For E-Glass/Vinyl Ester-Reinforced Polymer With Nanoclay, Shu-Kai Yeh Dec 2003

Alkaline Durability Tests For E-Glass/Vinyl Ester-Reinforced Polymer With Nanoclay, Shu-Kai Yeh

Graduate Theses, Dissertations, and Problem Reports

Two kinds of GFRP (glass fiber reinforced plastics) composite materials were prepared and used in this study. One was E-glass/vinyl ester glass fiber reinforced polymer (plain GFRP) and the other was nano-GFRP prepared with the addition of 1 wt% of CloisiteRTM 10A nanoclay. These samples were aged in an alkaline solution (pH = 13.2) with 3560N (800-lbs), 2225N (500-lbs) and 885N (200-lbs) of sustained load, which were 50%, 31% and 12.5% of the tensile strength, respectively. Time to failure or tensile strength reduction was measured and used to determine durability of the samples in terms of Aging Index, which was …


Fungi Associated With Northern Red Oak (Quercus Rubra ) Acorns, Dawn M. Washington Dec 2003

Fungi Associated With Northern Red Oak (Quercus Rubra ) Acorns, Dawn M. Washington

Graduate Theses, Dissertations, and Problem Reports

Poor regeneration of northern red oak is widespread in the central hardwood region. A two-part study was conducted to determine what fungi are associated with and cause cotyledon discoloration of northern red oak acorns. The field study determined that simulated small mammal notching, surface sowing, time, and site all play a significant role in the amount of cotyledon discoloration in acorns as well as the number of acorns with discoloration. However, germination rate was only affected by site and surface sowing, while seedling vigor ratings were actually higher when acorns had discolored cotyledons. The five species of fungi isolated most …


Distributed Dispatchers For Partially Clairvoyant Schedulers, Kiran S. Yellajyosula Dec 2003

Distributed Dispatchers For Partially Clairvoyant Schedulers, Kiran S. Yellajyosula

Graduate Theses, Dissertations, and Problem Reports

This work focuses on the empirical evaluation of distributed dispatching strategies on shared and distributed memory architectures for hard real-time systems. The dispatching model accommodates process parameter variability and analyzes the effect of variable execution times.;Hard real-time systems are modeled in the E-T-C scheduling framework and dispatched if a valid schedule exists. We examine the dispatchability of Partially Clairvoyant schedules of different sizes and varying deadlines under reasonable assumptions. The effect of scaling up the number of processors used by the dispatcher is also studied. The results validate the superiority of the distributed strategies over sequential dispatching and scalability of …


Evaluating Runoff Water Quality And Ammonia Volatilization In Three Turkey Litter Application Methods, Michael Dale Shamblin Dec 2003

Evaluating Runoff Water Quality And Ammonia Volatilization In Three Turkey Litter Application Methods, Michael Dale Shamblin

Graduate Theses, Dissertations, and Problem Reports

Poultry litter is an important nutrient source in crop production. However, the traditional practice of broadcasting poultry litter on the soil surface could result in nutrient losses in runoff as well as substantial ammonia volatilization losses, which could adversely affect both the environment and agricultural productivity. This research compared nutrient runoff (natural and simulated) losses on 1 m x 2 m plots and ammonia volatilization from different turkey litter application methods (broadcast, surface-banded, incorporated band, and control) applied in triplicate. No significant differences were observed between any of the treatments in any of the runoff constituents measured. Over three runoff …


Identity Formation Of Adolescents Involved In Selected Structured Activities, Sara A. Drake Dec 2003

Identity Formation Of Adolescents Involved In Selected Structured Activities, Sara A. Drake

Graduate Theses, Dissertations, and Problem Reports

Identity formation is seen as the primary developmental task during adolescence according to Erikson (1968). Adolescents' involvement in structured activities such as extracurricular activity, 4-H, and volunteerism were examined to determine their associations with identity formation. Researcher James Marcia (1966) developed four statuses of identity formation: diffusion, foreclosure, moratorium, and achieved. Categorization in one of the four statuses depends upon the levels of both crisis and commitment. Adolescents who are in the identity-diffused category have had no crisis or made no commitment. Those who foreclose, have made a commitment, but have had no crisis. Moratorium is a state of exploration, …


Brook Trout (Salvelinus Fontinalis) Movement And Habitat Use In A Headwater Stream Of The Central Appalachian Mountains Of West Virginia, Marisa Nel Logan Dec 2003

Brook Trout (Salvelinus Fontinalis) Movement And Habitat Use In A Headwater Stream Of The Central Appalachian Mountains Of West Virginia, Marisa Nel Logan

Graduate Theses, Dissertations, and Problem Reports

Brook trout (Salvelinus fontinalis) are the only salmonid native to the Appalachians. They are a resilient species, populating small, low productive streams. Although such streams have historically been abundant in the Appalachians, brook trout populations have been threatened due to habitat degradation such as logging and acidification of waters. The objective of this study was to evaluate brook trout habitat use, home range, and movement patterns in an Appalachian headwater stream during spring and more specifically high flow events. I implanted brook trout with radio tags and tracked their movement for approximately 30 days during late spring 2002 and early …


Aquaculture-Related Stress On Rainbow Trout (Oncorhynchus Mykiss) And Arctic Char (Salvelinus Alpinus), Christopher D. Nelson Dec 2003

Aquaculture-Related Stress On Rainbow Trout (Oncorhynchus Mykiss) And Arctic Char (Salvelinus Alpinus), Christopher D. Nelson

Graduate Theses, Dissertations, and Problem Reports

Recent expansions in aquaculture characterize it as one of the fastest growing segments of the U.S. agricultural sector. Expansion has been facilitated by increased production of many important aquatic species including catfish, salmon, trout, tilapia, shrimp, oysters, and crawfish. West Virginia aquaculture, also an expanding industry, is currently characterized by small-scale, widely dispersed farms. To facilitate future expansion of aquaculture in West Virginia, focuses on product quality as well as production efficiency, identification of limiting factors and investigation into new or alternative management techniques are needed. Objectives of this project were to determine the effects of nitrite and carbon dioxide …


Pharmaceutical Quality Performance Of Folic Acid Supplements, Islam Rasem Younis Dec 2003

Pharmaceutical Quality Performance Of Folic Acid Supplements, Islam Rasem Younis

Graduate Theses, Dissertations, and Problem Reports

The vitamin folic acid has received considerable attention in the 1990s because of its preventative role against diseases such as neural tube defects, cardiovascular diseases, and psychiatric illness.;A primary concern is the pharmaceutical quality, potency, and efficacy of commercially available folic acid products and label claims. The results showed that there has been significant progress since the 1990's in the improved quality of commercially available folic acid products in meeting USP standards.;Products were also tested in physiologically relevant solutions. Most notably, all the tested products failed to release more than 75% of the active ingredient in 60 minutes in simulated …


Synthesis And Characterization Of Molecularly Imprinted Polymers And Their Application In Preconcentrators For Gas Phase Sensors, Yi Fu Dec 2003

Synthesis And Characterization Of Molecularly Imprinted Polymers And Their Application In Preconcentrators For Gas Phase Sensors, Yi Fu

Graduate Theses, Dissertations, and Problem Reports

Various of molecularly imprinted polymers were synthesized by different protocols. Piezoelectric quartz crystals coated with molecularly imprinted polymers were prepared to detect small organic vapors. Hydroquinone (HQ) and Phenol (P) have been used as non-covalent bound templates in order to generate shape-selectivity cavities in the polymer matrix. The recognition film was immobilized on the crystal surface via a pre-coated Poly(isobutylene) layer. The selective behaviors of the imprinted polymer films were studied by their steady-state response to various kinds of small organic vapors. The partition coefficients of polymers toward vapors were evaluated. The imprinted polymers exhibit high sensitivity and selectivity toward …


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

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 …


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

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. …


Sport Psychology Strategies, Types Of Social Support, And Adherence To Injury Rehabilitation Among University Student -Athletes, Kenneth Tubilleja Dec 2003

Sport Psychology Strategies, Types Of Social Support, And Adherence To Injury Rehabilitation Among University Student -Athletes, Kenneth Tubilleja

Graduate Theses, Dissertations, and Problem Reports

The present study examined differences between levels of adherence to athletic injury rehabilitation (SIRAS; Brewer, Van Raalte, Petitpas, Sklar, & Ditmar, 1995) among injured student-athletes on their use of sport psychology strategies (TOPS; Thomas, Murphy, & Hardy, 1999) and their perceived social support (SSS-C; Richman, Rosenfeld, & Hardy, 1993). Relationships between adherence to athletic injury rehabilitation and sport psychology strategies and perceived social support were also investigated. In addition, participants' use and training in sport psychology strategies was explored. The sample consisted of 35 student-athletes from 1 NCAA Division I and 3 Division II institutions who sustained athletic injuries that …


Novel Syntheses Of Indoles, Quinoxalines, 2-Quinoxalinones, 2-Alkylbenzimidazoles And Other Heterocycles, Jeffery M. Wallace Dec 2003

Novel Syntheses Of Indoles, Quinoxalines, 2-Quinoxalinones, 2-Alkylbenzimidazoles And Other Heterocycles, Jeffery M. Wallace

Graduate Theses, Dissertations, and Problem Reports

Using a palladium-catalyzed reductive N-heteroannulation method previously discovered in our labs, a 20 mmol synthetic route to methyl indole-4-carboxylate has been developed. Methyl indole-4-carboxylate is synthesized in four steps, with the key step being the reductive cyclization of methyl 2-ethenyl-3-nitrobenzoate in good overall yield. This cyclization method has been modified and applied to the preparation of quinoxalines, 2-quinoxalinones and other heterocyclic compounds. We also propose a possible mechanism for these transformations.;In addition, a novel method to 2-alkylbenzimidazoles has been developed. The thermal reaction of 2-azidonitrobenzenes and various aldehydes give 2-alkylbenzimidazoles generally in moderate yield.


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

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 …


Development And Validation Of A Measure To Assess Physician Readiness To Prescribe Drug Therapies For Post-Myocardial Infarction Patients, Siddhesh Ajit Kamat Dec 2003

Development And Validation Of A Measure To Assess Physician Readiness To Prescribe Drug Therapies For Post-Myocardial Infarction Patients, Siddhesh Ajit Kamat

Graduate Theses, Dissertations, and Problem Reports

National guidelines recommend the use of beta-blockers, aspirin, and ACE-inhibitors in the management of post MI patients. These target drug classes continue to be under-prescribed; information on physicians' decision-making process requires attention and behavior change interventions have been proposed. This pilot study uses the Transtheoretical Model of Change; physicians' salience for the pros and cons of prescribing target drug classes constitutes the decisional balance measure, which can be used to predict their stage of readiness. A survey instrument was mailed to a sample of West Virginia physicians and 55 usable responses (34%) were received. Majority of the physicians self-reported in …


Enhancing Quality And Extending Shelf Life Of Rainbow Trout (Oncorhynchus Mykiss) By Vitamin E Supplementation And Post-Harvest Antimicrobial Intervention, Nalini Kamireddy Dec 2003

Enhancing Quality And Extending Shelf Life Of Rainbow Trout (Oncorhynchus Mykiss) By Vitamin E Supplementation And Post-Harvest Antimicrobial Intervention, Nalini Kamireddy

Graduate Theses, Dissertations, and Problem Reports

Rainbow trout were fed a control (191 mg/kg) or the control diet supplemented with 5000 mg alpha-tocopherol/kg. Fish were sampled at 2, 3, 4, 5, 7, and 9 weeks of feeding; at each week fillets were evaluated at 0, 7, and 14 d. Supplementation increased fillet alpha-tocopherol content, and TBARS value were not affected. A feeding by storage time interaction was observed for fat content, psychrotrophic counts, cook yield, and shear force. For antimicrobial intervention, fillets were not treated or were dipped in water, 50 ppm ASC, and 1000 ppm ASC for 30 s. Fillets were stored at 1--2°C for …


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

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 …


Cerulean Warbler Relative Abundance And Frequency Of Occurrence Relative To Large-Scale Edge, Scott B. Bosworth Dec 2003

Cerulean Warbler Relative Abundance And Frequency Of Occurrence Relative To Large-Scale Edge, Scott B. Bosworth

Graduate Theses, Dissertations, and Problem Reports

Cerulean Warblers (Dendroica cerulea) were studied in southwestern West Virginia where the coal mining technique of mountaintop mining/valley fill (MTMVF) continues to perforate large contiguous tracts of deciduous forest. My study objectives were to (1) quantify abundance and probability of occurrence of Cerulean Warblers relative to distance from large-scale edge (defined as reclaimed MTMVF sites) and (2) relate habitat structure and landscape characteristics to the species' probability of occurrence. Cerulean Warbler abundance increased significantly (P < 0.10) with distance from reclaimed mine edge. However, percent occurrence relative to distance from mine edge was not significant, suggesting a degree of tolerance to the large-scale edge created by MTMVF. Abundance was significantly greater on ridges than bottomlands. Percent occurrence did not differ among the three slope positions but followed a trend similar to abundance. Consequently, disturbances such as MTMVF in which ridges are removed may have a greater impact on populations compared to other sources of fragmentation where ridges are not disturbed. Other habitat structure analyses suggest good indicators of Cerulean Warbler presence are the more productive sites on northwest to east facing slopes and low sapling density. Similarly, Cerulean Warbler abundance was positively associated with more productive sites and snag density. Important landscape characteristics positively associated with abundance were large blocks of mature deciduous forest and low edge density. Mountaintop mining/valley fill alters the spatial configuration of forested habitats in southwestern West Virginia, thus creating less suitable habitat and edge effects that negatively affect Cerulean Warbler abundance, occurrence, and distribution in the reclaimed mine landscape.


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

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 …


Implementing Software Engineering Practices In Small Industry With A Focus On Requirements Elicitation, James Clifford Fleming Dec 2003

Implementing Software Engineering Practices In Small Industry With A Focus On Requirements Elicitation, James Clifford Fleming

Graduate Theses, Dissertations, and Problem Reports

I have been involved in small industry for 33 years and I have seen how the evolution of computers and software has affected small companies striving to grow in their market place by trying to take advantage of an evolving technology. Many times an individual is assigned the task of developing software to fit the company's needs and begins the process without any formal training in the practices of Software Engineering. My Thesis will discuss my evolving skills, gained through my Masters in Software Engineering degree work, as a Software Engineer and how I have been able to implement proper …


Parametric Modeling Of Bolted Joints Between Components Made Of Particulate Composite Materials, Vasudha Goteti Dec 2003

Parametric Modeling Of Bolted Joints Between Components Made Of Particulate Composite Materials, Vasudha Goteti

Graduate Theses, Dissertations, and Problem Reports

Particulate metal matrix composites (MMC) exhibit higher stiffness, strength and wear resistance compared to metal alloys. They exhibit superior compressive and buckling strength because of their higher plastic modulus. MMC's can operate at very higher temperatures than fiber-reinforced polymer composites. Their isotropic behavior and forming ability by conventional methods makes them a better choice for low-cost applications. They have good thermal conductivity, high electrical conductivity and low thermal expansion.;The main objective of this study is to predict numerically the stress distributions around the hole in a bolted joint made of particulate metal matrix composite and to investigate the associated load …


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

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.


Corrosion Of High-Chromium And Conventional Steels Embedded In Concrete, Vijayakumar Nachiappan Dec 2003

Corrosion Of High-Chromium And Conventional Steels Embedded In Concrete, Vijayakumar Nachiappan

Graduate Theses, Dissertations, and Problem Reports

Corrosion of steel in concrete structures sometimes led to the unexpected failure of the concrete bridges in United States before their intended service life. High-chromium steel has been developed as a replacement for conventional steel in concrete because it may have a capability to retard the corrosion rate. In the present study, high-chromium and conventional steels were subjected to accelerated corrosion, and compared for their corrosion performance under chloride environment.;Corrosion rates of high-chromium and conventional steel rebars were compared by conducting two studies. One was with concrete blocks and the other was with bare steel rebars. In the former study, …


Characterization Of Exhaust Emissions From Catalyzed Trap-Equipped Non-Road Heavy-Duty Diesel Engines, Vinay Nagendran Dec 2003

Characterization Of Exhaust Emissions From Catalyzed Trap-Equipped Non-Road Heavy-Duty Diesel Engines, Vinay Nagendran

Graduate Theses, Dissertations, and Problem Reports

An emissions and engine performance study was conducted to explore the effects of ultra low sulfur fuels on an off-road, heavy-duty engine retrofitted with catalyzed traps. The study was conducted, on an 8 cylinder, mechanically controlled Caterpillar 3408, rear engine of a Scraper. An in-field transient duty cycle was determined by logging the engine speed and torque using an Electronic Control Unit (ECU) communication adapter on the Scraper. The test fuels included California Air Resources Board (CARB) off-road diesel fuel, Fischer-Tropsch and Emission Control Diesel-1 (ECD1) diesel fuels. The engine was retrofit with two different types of diesel particulate filters …