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2003

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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 (ETD)

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, …


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 (ETD)

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 …


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. …


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 (ETD)

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 …


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 (ETD)

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 …


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. …


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 …


One-Dimensional Transient Numerical Modeling Of A Micro-Power Generation System, Emre Tatli Dec 2003

One-Dimensional Transient Numerical Modeling Of A Micro-Power Generation System, Emre Tatli

Graduate Theses, Dissertations, and Problem Reports (ETD)

Two core modules of a more comprehensive model for analyzing the flow of fluids in a hybrid system including a fuel cell are developed. First part consists of a new procedure for scaling turbomachinery maps. In the last few decades, the sizes of turbomachinery have been getting smaller and smaller for various purposes. New designs have pushed the limits of power generation to be in more compact sizes, which lead to smaller compressors and turbines. For new designs, it is important to know how the turbomachinery in the system will behave at certain conditions. But it is not practical to …


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]. …


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 (ETD)

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 …


Plant-Wide Energy Assessment Using A Systems Approach, Rajkumar Selvaraj Dec 2003

Plant-Wide Energy Assessment Using A Systems Approach, Rajkumar Selvaraj

Graduate Theses, Dissertations, and Problem Reports (ETD)

Energy plays a central role in the operation of the industrialized U.S. economy. Industry is historically the largest consuming sector of the economy with more than 60 percent of the energy consumed for manufacturing. The U.S. chemical industry is the world's largest producer of chemicals producing over 25 percent of the total production worldwide. In a chemical industry, the energy is used to supply heat and power for manufacturing processes and for energy feedstock. Due to the energy intensive nature of chemical industries, energy assessments performed could yield huge savings in energy and cost.;The aim of this research is to …


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 …


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 …


Influence Of Live -Load Deflections On Superstructure Performance Of Slab On Steel Stringer Bridges, Haiyong Wu Dec 2003

Influence Of Live -Load Deflections On Superstructure Performance Of Slab On Steel Stringer Bridges, Haiyong Wu

Graduate Theses, Dissertations, and Problem Reports (ETD)

High performance steel (HPS), specifically HPS 70W, was introduced to the bridge market in the United States in the late 1990s. With its added strength, greater durability, and improved weldability, HPS allows engineers to design longer and shallower spans, which may increase the live-load deflections. The AASHTO Standard Specification limits live-load deflections to L/800 for ordinary bridges and L/1000 for bridges in urban areas subjected to pedestrian use. Bridges designed by the AASHTO LRFD Specification have an optional deflection limit. Previous research focused on evaluating AASHTO live-load deflection limits showed that the justification for existing deflection limits was not clearly …


Reaction Engineering Study Of Natural Gas Hydrate Formation In Special Packed -Bed Reactors By Controlling The Boundary Layer Surfaces Of The Gas -Liquid -Solid Phases, Budhijanto Budhijanto Dec 2003

Reaction Engineering Study Of Natural Gas Hydrate Formation In Special Packed -Bed Reactors By Controlling The Boundary Layer Surfaces Of The Gas -Liquid -Solid Phases, Budhijanto Budhijanto

Graduate Theses, Dissertations, and Problem Reports (ETD)

Natural gas hydrates (NGH) are crystalline compounds that consist of water and natural gas (NG) molecules. By hydrogen bonds, water molecules form a regular lattice structure containing many cavities. NG molecules occupy the cavities, and therefore stabilize the cavities. NGH are considered to be one of the most potential alternative world energy resources. The applications of NGH in other fields, such as NG purification, storage, and transportation, are also possible. To obtain the full benefits of all the possible applications of NGH, a full understanding of the kinetics of NGH formation is needed.;Strictly speaking, the experimental works of reproducible intrinsic …


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 …


Getting The "Big Picture" In Engineering: Using Narratives And Conceptual Maps, Glenn W. Ellis, Borjana Mikic, Alan N. Rudnitsky Dec 2003

Getting The "Big Picture" In Engineering: Using Narratives And Conceptual Maps, Glenn W. Ellis, Borjana Mikic, Alan N. Rudnitsky

Engineering: Faculty Publications

The features and progress of Picker Engineering Program at Smith College are discussed. This program is the first undergraduate program leading to a degree in engineering at a women's liberal arts college. The program's goal is to educate engineers who are adaptable to the rapidly changing demands of society. The strategies which focus on productive ways of processing information, ways that involve the sort of intentions and conciousness necessary for meaningful learning are also discussed.


Helping Students Organize And Retrieve Their Understanding Of Dynamics, Glenn W. Ellis, Warren A. Turner Dec 2003

Helping Students Organize And Retrieve Their Understanding Of Dynamics, Glenn W. Ellis, Warren A. Turner

Engineering: Faculty Publications

When confronted with the large amount of information presented in an introductory physics course, students often have difficulty assimilating the concepts and seeing the big picture. Thus they may have difficulty transferring their knowledge to new situations. In this paper we present a conceptual framework that we have developed for teaching and applying dynamics at both the secondary school and college levels. In this framework the causes of motion are graphically related to the description of motion using Newton's laws and impulse/momentum relationships. The framework accommodates translation and rotation, multiple dimensions, and time-varying forces. In addition to presenting the framework, …


Rank-Aware Query Optimization, Ihab F. Ilyas, Rahul Shah, Walid G. Aref, Jeffrey S. Vitter, Ahmed K. Almagarmid Dec 2003

Rank-Aware Query Optimization, Ihab F. Ilyas, Rahul Shah, Walid G. Aref, Jeffrey S. Vitter, Ahmed K. Almagarmid

Department of Computer Science Technical Reports

No abstract provided.


Building Energy-Efficient Web Servers Using Low Power Devices: Opportunities And Challenges, Le Cai Dec 2003

Building Energy-Efficient Web Servers Using Low Power Devices: Opportunities And Challenges, Le Cai

Department of Electrical and Computer Engineering Technical Reports

Power consumption has become one major challenge in designing highperformance servers. Recently, some researchers postulate that better energy e±ciency can be achieved by using low power devices originally designed for mobile embedded systems. In this report, we validate this hypothesis by measuring the power and the performance of web servers on system level. We consider the power and the energy consumption of processors, memory, and hard disk drives. Our data indicate that, compared with a Pentium4-based web server, a XScale-based computer can achieve more than 1.7 times higher energy e±ciency (web pages per Joule) while its throughput (web pages per …


Dynamics And Topology Optimization Of Piezoelectric Fans, P Buermann, Arvind Raman, S V. Garimella Dec 2003

Dynamics And Topology Optimization Of Piezoelectric Fans, P Buermann, Arvind Raman, S V. Garimella

CTRC Research Publications

Piezoelectric fans are very low power, small, very low noise, solid-state devices that have recently emerged as viable thermal management solutions for a variety of portable electronics applications including laptop computers, cellular phones and wearable computers. Piezoelectric fans utilize piezoceramic patches bonded onto thin, low frequency flexible blades to drive the fan at its resonance frequency. The resonating, low frequency blade creates a streaming airflow directed at key electronics components. The optimization of a piezoelectric fan with two symmetrically placed piezoelectric patches is investigated through an analytical Bernoulli-Euler model as well as a finite element (FE) model of the composite …


On Improving Recursive Bipartitioning-Based Placement, Chen Li, Cheng-Kok Koh Dec 2003

On Improving Recursive Bipartitioning-Based Placement, Chen Li, Cheng-Kok Koh

Department of Electrical and Computer Engineering Technical Reports

We present an improved partitioning-based placement tool in terms of the half-perimeter wirelength. In contrast to placement tools that exploit white spaces to reduce the routing congestion, our placement tool exploits white spaces to reduce the total wirelength. In particular, we generate white spaces during the legalization step and treat white spaces as pseudo cells during the detailed placement step. On IBM benchmarks, our results are better than those of Feng Shui [1] and Capo [4] by 1.8% and 11.1%, respectively, on the average. Our results are comparable to those of Dragon [17]. On the synthetic benchmarks PEKO, our placement …


Viewing The Learning Process: Assessment Via Usability Testing, Vicki M. Eller, Steve Eugene Watkins, Richard H. Hall Dec 2003

Viewing The Learning Process: Assessment Via Usability Testing, Vicki M. Eller, Steve Eugene Watkins, Richard H. Hall

Business and Information Technology Faculty Research & Creative Works

Learning through Computer-Based Activities Provides a Multi-Modal Approach in Which the User Can Select the Educational Media and Process. Effective Development of These Activities Requires an Understanding of User Interactivity. Traditional Assessment, Such as Test Scores and Subjective Surveys, Looks at End Results and Attitudes. This Method Does Not Monitor the Learning Process. in Particular Developer Needs to Accommodate Diverse Usage Preferences and Choices. Hence, Assessment Should Involve Usability Measures that Are Quantitative and Qualitative. Usability Testing Records Usage Patterns and User Reactions. a Usability Laboratory Was Created at the University of Missouri-Rolla. It is Supplements the Traditional Assessment for …


An Algorithm For Clearing Combinatorial Markets, Josiane Domgang Nzouonta Dec 2003

An Algorithm For Clearing Combinatorial Markets, Josiane Domgang Nzouonta

Theses and Dissertations

It was recently shown possible to solve single item auctions without revealing any secret except for the solution. Namely, with vMB-share [4], the seller and the buyer only learn each other's identity and the selling price for a chosen M+1 pricing scheme. No trusted party was necessary. In this thesis, we show how vMB-share can be extended for the clearing of combinatorial negotiations with several items, buyers and sellers. We first show how the more general problem can be reduced to a virtual form, relatively similar to the single-item auctions. Then, some modifications in the cryptographic techniques of vMB-share are …


Richmond Music Journal (2003-12) Dec 2003

Richmond Music Journal (2003-12)

Richmond Music Journal

No abstract provided.


Effect Of Partial Borate Autocausticizing On Causticizing Rate And Equilibrium, Murugavel Anbalagan Dec 2003

Effect Of Partial Borate Autocausticizing On Causticizing Rate And Equilibrium, Murugavel Anbalagan

Masters Theses

Borate autocausticizing can replace - total autocausticizing, or supplement the kraft lime cycle- partial autocausticizing. Partial autocausticizing is undergoing trials in several mills and has been recently commercialized in one mill. One common observation in the on-going trials is that the causticizing efficiency increases. The primary objectives of this research are to study the effect of metaborate on the causticizing rate, equilibrium and rate controlling parameters such as the temperature, concentration and sulfidity. The aim is to define the conditions that resulted in the increase of the causticizing efficiency.

The major findings of the research are that when the causticizing …


Contracts - Collective Bargaining - Federal District Court Improperly Dismissed All Claims By Professional Athlete When State Claims May Not Have Been Pre-Empted By The Labor Management Relations Act Due To Their Lack Of Dependence On The Collective Bargaining Agreement - Sprewell V. Golden State Warriors: National Basketball Association, 266 F.3d 979 (9th Cir. 2001), Reh'g En Banc Denied, 275 F.3d 1187 (9th Cir. 2001), John Kaplan Dec 2003

Contracts - Collective Bargaining - Federal District Court Improperly Dismissed All Claims By Professional Athlete When State Claims May Not Have Been Pre-Empted By The Labor Management Relations Act Due To Their Lack Of Dependence On The Collective Bargaining Agreement - Sprewell V. Golden State Warriors: National Basketball Association, 266 F.3d 979 (9th Cir. 2001), Reh'g En Banc Denied, 275 F.3d 1187 (9th Cir. 2001), John Kaplan

Seton Hall Journal of Sports and Entertainment Law

No abstract provided.


Fireworks, Fan Cams, And Lawsuits: A Guide To Stadium Scoreboards, Robert M. Jarvis, Phyllis Coleman Dec 2003

Fireworks, Fan Cams, And Lawsuits: A Guide To Stadium Scoreboards, Robert M. Jarvis, Phyllis Coleman

Seton Hall Journal of Sports and Entertainment Law

No abstract provided.


Evaluation Of 2,2'-Bipyridylpyridinetricarbonylrhenium (I) Triflate Complex As A Luminescent Probe For The Study Of Macromolecular Solution Dynamics, Richard Allen Allston Dec 2003

Evaluation Of 2,2'-Bipyridylpyridinetricarbonylrhenium (I) Triflate Complex As A Luminescent Probe For The Study Of Macromolecular Solution Dynamics, Richard Allen Allston

Seton Hall University Dissertations and Theses (ETDs)

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A Longitudinal Metric Study Of Postgresql Software Archeology In Open Source, Terry Franklin Byrum Dec 2003

A Longitudinal Metric Study Of Postgresql Software Archeology In Open Source, Terry Franklin Byrum

Computer Science Theses & Dissertations

Open source software development is credited as the basic fuel powering much of the Internet, especially the Web. While many organizations rely heavily on open source, few studies have focused on the dynamics of development methodology. This document contains the results of a longitudinal metric study of the open source database PostgreSQL representing an 8 year period of community development. This study is software archeology, excavating bits of an Internet community, a cultural group, for understanding. Longitudinally, McCabe's cyclomatic complexity and Halstead's software science change tempo in accordance with PostgreSQL's maturity, though meritocracy practices of open source might suggest greater …