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2004

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Articles 361 - 390 of 2785

Full-Text Articles in Engineering

An Error Analysis Of The Multirate Method For Power System Transient Stability Simulation, Jingjia Chen, Mariesa Crow, Badrul H. Chowdhury, Levent Acar Oct 2004

An Error Analysis Of The Multirate Method For Power System Transient Stability Simulation, Jingjia Chen, Mariesa Crow, Badrul H. Chowdhury, Levent Acar

Electrical and Computer Engineering Faculty Research & Creative Works

This efficient application of any numerical integration method depends on accurate estimation of the local truncation error to govern step size control. In this paper, the local truncation error of the multirate method using the forward Euler integration is derived leading to the calculation of the optimal step ratio. The techniques of applying multirate method in power systems are discussed. By implementing the multirate method in a practical power system example, the multirate strategies are proved to be efficient compared with traditional simulation methods.


Bulk Power System Low Frequency Oscillation Suppression By Facts/Ess, Li Zhang, Y. Liu, Michael R. Ingram, Dale T. Bradshaw, Steve Eckroad, Mariesa Crow Oct 2004

Bulk Power System Low Frequency Oscillation Suppression By Facts/Ess, Li Zhang, Y. Liu, Michael R. Ingram, Dale T. Bradshaw, Steve Eckroad, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

Low frequency oscillations in the interconnected power systems are observed all around the world. In this paper, the authors studied the inter-area mode low frequency oscillations by analyzing the phenomena in Nashville area of the Tennessee Valley Authority (TVA) system. Our study revealed 4 dynamic groups of generators in this area. Within each group, generators swing together and have the same dynamic trend. Generators from different dynamic groups swing against each other. The authors studied the possibility of using a FACTS/ESS controller to damp the low frequency oscillations in Nashville area. The active power is controlled to damp the low …


Huffman Approach To Opcode Compression, Jason B. Shreve Oct 2004

Huffman Approach To Opcode Compression, Jason B. Shreve

Electrical & Computer Engineering Theses & Dissertations

Instructions are the building blocks of computer programs. They are composed of opcodes, which uniquely identify each instruction, and the operands or data. In most architectures, the instruction length is a set multiple of the word size. The size and number of operands vary by instruction. Due to programmer usage, program need, or compiler design, opcodes do not occur with a constant distribution. Likely, some opcodes occur very frequently, whereas others occur very infrequently or not at all. If the length of an opcode were representative of its frequency, compression in program size might be achieved.

This thesis is an …


Distal Placement Of An End-To-Side Bypass Graft Anastomosis A 3-D Computational Study, John Robert Di Cicco Oct 2004

Distal Placement Of An End-To-Side Bypass Graft Anastomosis A 3-D Computational Study, John Robert Di Cicco

Mechanical & Aerospace Engineering Theses & Dissertations

A three-dimensional computational fluid dynamics study of blood flow through stenotic arteries has been conducted. Flow phenomena, such as separation regions and turbulence, can be found distal to an arterial stenosis. Frequently, a bypass graft using an end-to-side technique is attached to a stenotic artery to restore adequate blood flow. However, a significant percentage of these grafts fail after thirty postoperative days due to intimal hyperplasia development around the distal anastomosis. Moreover, aberrant wall shear rates have been implicated as a factor in the development of intimal hyperplasia. Thus, the present study examines whether placement of the distal end of …


Vector Operations In Superscalar Architectures, Nathan Daniel Flinn Oct 2004

Vector Operations In Superscalar Architectures, Nathan Daniel Flinn

Electrical & Computer Engineering Theses & Dissertations

Vector calculations are very prevalent today. Though the vector-processing computer is quite an old concept, superscalar processors lack hardware support for vector operations. This thesis investigates whether an ordinary superscalar computer architecture can be designed to include hardware support for improved vector operations without drastically changing the existing superscalar design and behavior. A computer architecture design was created and implemented that included the vector multiply (dot product) operation. The design includes a Vector Operations Unit that captures incoming vector operations and generates the necessary set of machine instructions to complete the vector operation internally. It then delivers these instructions to …


Modeling And Simulation Of Photonic Crystal Fibers Using Finite Difference Frequency Domain Method, Md. Khalid Ikram Oct 2004

Modeling And Simulation Of Photonic Crystal Fibers Using Finite Difference Frequency Domain Method, Md. Khalid Ikram

Electrical & Computer Engineering Theses & Dissertations

Photonic crystal fibers (PCFs) allow guiding light in low-index core. These fibers exhibit properties such as single-mode operation in broad wavelength region. The mode shape and group velocity dispersion can be controlled by designing the microstructures of the cladding. In order to study these properties, a fast, efficient, and highly accurate numerical modeling method is required.

A full-vectorial finite-difference frequency-domain (FDFD) method is implemented. The modal properties of conventional step index fiber and index-guiding PCF are analyzed using this modeling technique. Compared to plane wave expansion and biorthogonal basis methods, FDFD is found to be simple, reliable, and efficient. PCFs …


Procedure Manual For Implementation Of Gasb 34 By Indiana Local Public Agencies, Indiana Ltap, Government Fixed Asset Services Oct 2004

Procedure Manual For Implementation Of Gasb 34 By Indiana Local Public Agencies, Indiana Ltap, Government Fixed Asset Services

Indiana Local Technical Assistance Program (LTAP) Publications

This assistance manual is meant to assist participating governments with certain aspects of the general infrastructure retroactive reporting implementation issues in light of the Governmental Accounting Standards Board Statement No. 34. This assistance manual may prove to be of assistance in prospective reporting as well.

General infrastructure assets per the GASB are comprised of roads, bridges, tunnels, drainage systems, water and sewer systems, dams, and lighting systems. If significant, a government should also include sidewalks, traffic signals, and improved alleys in their reporting. Also to be included are a government's rights-of-way.

The capital asset and general infrastructure provisions of GASB …


Perceptions Of Practitioners And Engineering Educators And Students Regarding Requisite Skills For Effective Design Of Complex Systems, Melanie A. Thom Oct 2004

Perceptions Of Practitioners And Engineering Educators And Students Regarding Requisite Skills For Effective Design Of Complex Systems, Melanie A. Thom

Open Access Theses

Both popular press and academic journals have reported increasing trends in design failures attributed to engineering errors, poor planning and inadequate design decisions as demonstrated by mission failures, product failures and increasing manufacturing and support costs ((McMasters & Matsch, 1996; Oberg, 2000; Lowery, 1998; Hayes & Wheelwright, 1984; Schlager, 1994; Scott, 1999, 1999a, 1999b). The authors of the articles agree that graduating engineers are competent at formulaic analysis, but they suggest a perceived lack of fundamental skills necessary for design activities. This lack of skills is described in broad terms but the descriptions lack specific metrics for assessing the possession …


The Use Of Vegetation In The Stabilization, Reclamation, And Remediation Of Impacted Indot Soils, Mark S. Mcclain, M. K. Banks, A. Paul Schwab Oct 2004

The Use Of Vegetation In The Stabilization, Reclamation, And Remediation Of Impacted Indot Soils, Mark S. Mcclain, M. K. Banks, A. Paul Schwab

JTRP Technical Reports

The major goal of this project was to write the manual PhytoRemediate®: Phytoremediation Decision Guide for Transportation Engineers and the attached compact disk PhytoRemediate®: Training Module for Transportation Engineers to assist transportation engineers and other professionals in the applicability of phytoremediation as an effective method of remediation engineering design. This guide is not a design manual, but identifies the decision-making processes necessary for successful remediation of contaminated sites using phytoremediation.

A phytoremediation users' manual PhytoRemediate®: Phytoremediation Decision Guide for Transportation Engineers was developed to assist INDOT personnel in the areas of site assessment, plant species selection, plant …


2004 (Fall) Ensi Informer Magazine, Morehead State University. Engineering Sciences Department Oct 2004

2004 (Fall) Ensi Informer Magazine, Morehead State University. Engineering Sciences Department

ENSI Informer Magazine Archive

The ENSI Informer Magazine published in the fall of 2004.


Achromatic Angle-Insensitive Infrared Quarter-Wave Retarder Based On Total Internal Reflection At The Si–Sio2 Interface, R. M.A. Azzam, Cristina L. Spinu Oct 2004

Achromatic Angle-Insensitive Infrared Quarter-Wave Retarder Based On Total Internal Reflection At The Si–Sio2 Interface, R. M.A. Azzam, Cristina L. Spinu

Electrical Engineering Faculty Publications

An achromatic infrared (λ = 1.2–4 μm), Si-prism quarter-wave retarder (QWR) is described that uses total internal reflection at a buried Si–SiO2 interface at an angle of incidence φ near 33°, where ∂Δ/∂φ = 0. The retardance Δ deviates from 90° by <±2° within a field of view of ±10° (in air) over the entire bandwidth. Because the SiO2 layer at the base of the prism is optically thick, this QWR is unaffected by environmental contamination.


A Template-Based Conceptual Modeling Infrastructure For Simulation Of Physical Security Systems, Paul Savory Oct 2004

A Template-Based Conceptual Modeling Infrastructure For Simulation Of Physical Security Systems, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

Although simulation is one of the most innovative and cost-effective tools for modeling and analyzing a system, simulation studies often fail to provide any useful results. One reason is attributed to the fact that model formulation depends on the skills of the analyst. This paper describes a research to develop a conceptual modeling infrastructure to assist a simulation analyst in specifying components for studying physical security systems. The modeling framework has been programmed as an internet-based web application. Using the application, the successful development and implementation of a physical security simulation model will be aided by a defined scientific methodology …


Science For Stewardship: Multidisciplinary Research On Uss Arizona, Matthew A. Russell, Larry E. Murphy, Donald L. Johnson, Timothy J. Foecke, Pamela J. Morris, Raphy Mitchell Oct 2004

Science For Stewardship: Multidisciplinary Research On Uss Arizona, Matthew A. Russell, Larry E. Murphy, Donald L. Johnson, Timothy J. Foecke, Pamela J. Morris, Raphy Mitchell

Department of Mechanical and Materials Engineering: Faculty Publications

The National Park Service’s Submerged Resources Center and USS Arizona Memorial are conducting and coordinating research directed at understanding the nature and rate of natural processes affecting the deterioration of the USS Arizona in Pearl Harbor, Hawaii. The USS Arizona Preservation Project is designed to be multi-year, interdisciplinary and cumulative, with each element contributing to developing an overall management strategy designed to minimize environmental hazard from fuel oil release and provide the basic research required to make informed management decisions for long-term preservation. The primary project focus is toward acquiring requisite data for understanding the complex corrosion and deterioration processes …


In-Drift Natural Convection And Condensation, Stephen W. Webb, Phillip Rogers, John Del Mar, Darrell Svalstad, Cliff Howard, Ernest Hardin, Bechtel Saic Company, Llc Oct 2004

In-Drift Natural Convection And Condensation, Stephen W. Webb, Phillip Rogers, John Del Mar, Darrell Svalstad, Cliff Howard, Ernest Hardin, Bechtel Saic Company, Llc

Publications (YM)

The Yucca Mountain repository configuration consists of waste packages stored inside of underground tunnels, or drifts. The waste packages generate heat due to radioactive decay, and moisture flows into and out of the drifts in liquid and vapor form. Heat and mass transfer within the drifts, including interaction with the surrounding rock, are potentially important processes for the performance of the repository. The present report documents models for in-drift heat and mass transfer during the post-closure period. Pre-closure, or ventilated, conditions are documented in a separate report (BSC 2004 [DIRS 169862]).


Dissolution, Reactor, And Environmental Behavior Of Zro2-Mgo Inert Fuel Matrix: Neutronic Evaluation Of Zro2-Mgo Inert Fuels, E. Fridman, A. Galperin, E. Shwageraus Oct 2004

Dissolution, Reactor, And Environmental Behavior Of Zro2-Mgo Inert Fuel Matrix: Neutronic Evaluation Of Zro2-Mgo Inert Fuels, E. Fridman, A. Galperin, E. Shwageraus

Fuels Campaign (TRP)

Second task of the BGU part of “Dissolution, Reactor, and Environmental Behavior of ZrO2-MgO Inert Fuel Matrix” project aims at evaluation of the fertile free fuel matrix composition effect on the fuel reactivity and corresponding reactivity limited burnup. Fertile free fuel with different MgO to ZrO2 ratio in the matrix will require different PuO2 loading in order to assure certain fuel cycle length. This is due to the fact that absorption cross section of Zr is slightly higher than that of Mg, although absorption in both of these elements is small compared to Pu. Therefore, the …


Lorentz-Violating Electrostatics And Magnetostatics, Quentin G. Bailey, V. Alan Kostelecký Oct 2004

Lorentz-Violating Electrostatics And Magnetostatics, Quentin G. Bailey, V. Alan Kostelecký

Publications

Electromagnetostatics experiments show promise for improving existing sensitivities to parity-odd coefficients for Lorentz violation in the photon sector.


Wind Speed Effect On L-Band Brightness Temperature Inferred From Eurostarrs And Wise 2001 Field Experiments, David G. Long, Jacqueline Etcheto, Emmanuel P. Dinnat, Jacqueline Boutin, Adriano Camps, Stephanie Contardo, J. Wesson, Jordi Font, J. Miller Oct 2004

Wind Speed Effect On L-Band Brightness Temperature Inferred From Eurostarrs And Wise 2001 Field Experiments, David G. Long, Jacqueline Etcheto, Emmanuel P. Dinnat, Jacqueline Boutin, Adriano Camps, Stephanie Contardo, J. Wesson, Jordi Font, J. Miller

Faculty Publications

The results from two field experiments in the Mediterranean Sea are used to study the wind speed dependence of brightness temperature at L-band. During the EuroSTARRS airborne experiment, an L-band radiometer made measurements across a large wind speed gradient, enabling us to study this dependence at high wind speed. We compare our results with a two-scale emissivity model using several representations of the sea state spectrum. While the results are encouraging, unfortunately the accuracy of the measurements does not permit us to distinguish between the so-called twice Durden and Vesecky spectrum and the Elfouhaily spectrum above 7 m X s-1. …


Semi-Autonomous Human-Uav Interfaces For Fixed-Wing Mini-Uavs, Randal Beard, Michael A. Goodrich, Morgan Quigley Oct 2004

Semi-Autonomous Human-Uav Interfaces For Fixed-Wing Mini-Uavs, Randal Beard, Michael A. Goodrich, Morgan Quigley

Faculty Publications

Sponsorship: DARPA, AFOSR. We present several human-robot interfaces that support real-time control of a small semi-autonomous UAV. These interfaces are designed for searching tasks and other missions that typically do not have a precise predetermined flight plan. We present a detailed analysis of a PDA interface and describe how our other interfaces relate to this analysis. We then offer quantative and qualitative performance comparisons of the interfaces, as well as an analysis of their possible real-world applications.


Effects Of Track Irregularities On Dynamic Responses Of A Moving Maglev Train, Aravind M. Hanasoge Oct 2004

Effects Of Track Irregularities On Dynamic Responses Of A Moving Maglev Train, Aravind M. Hanasoge

Mechanical & Aerospace Engineering Theses & Dissertations

The Maglev project at Old Dominion University is a collaboration between Old Dominion, American Maglev Technology (AMT), Lockheed Martin, other industry participants and the federal and state governments. This project began at the Norfolk campus in 2002. Under this project, researchers are aiming for a demonstrable engineering prototype that will operate smoothly at speeds of 40 - 45 miles per hour along the 3400 feet long track.

During testing, the vehicle is found to vibrate violently when operated on the ground. Furthermore, the vehicle failed to levitate when operated on the elevated track. As part of the investigation to determine …


Effects Of Initial Seated Position On Whiplash In Low Speed Rear-End Impacts Comparison And Study Using The Tno Rear Impact Dummy (Trid) Model, Manjunath P. Venkataramana Oct 2004

Effects Of Initial Seated Position On Whiplash In Low Speed Rear-End Impacts Comparison And Study Using The Tno Rear Impact Dummy (Trid) Model, Manjunath P. Venkataramana

Mechanical & Aerospace Engineering Theses & Dissertations

Despite numerous investigations devoted to its scrutiny, injury causing mechanism associated with rear-end impact collision producing injury such as Whiplash Associated Disorder (WAD) has remained a mystery. Several criteria have been proposed to predict the injury causing mechanism, but none have been universally accepted. The challenge lies in determining a set of testing procedures representative of real-world collisions, wherein the results obtained are not only the same as human testing, but remain consistent with various subjects and impact conditions. It is hypothesized that one of the most important considerations is the effect of initial seated position (ISP).

This thesis can …


Final Report: Review Of The Fits Program: Program Tasks, Goals And Pilot Training Initiatives, Alex Chaparro, Bonnie Lida Rogers, Christopher J. Hamblin Oct 2004

Final Report: Review Of The Fits Program: Program Tasks, Goals And Pilot Training Initiatives, Alex Chaparro, Bonnie Lida Rogers, Christopher J. Hamblin

Publications

In 2002 the FAA, academic and industry partners established the FAA/Industry Training Standards (FITS) program whose purpose is to modernize General Aviation (GA) pilot training. The FAA recognized the need to modernize training standards for pilots who would use new avionics technology that integrate the GPS (Global Positioning Systems) with the autopilot along with multifunction displays capable of depicting flight path, weather, terrain and traffic information. These avionics and displays are touted as improving safety by enhancing pilot Situational Awareness and reducing pilot workload. The new technology has highlighted the need for programs to train and certify pilots to use …


An Algorithm For Locating Fundamental Frequency (F0) Markers In Speech, Princy Dikshit Oct 2004

An Algorithm For Locating Fundamental Frequency (F0) Markers In Speech, Princy Dikshit

Electrical & Computer Engineering Theses & Dissertations

Speech has been the principal form of human communication since it began to evolve at least one hundred thousand years ago. Speech is produced by vibrations of the vocal cords. The rate of vibration of the cords is called fundamental frequency (F0) or pitch. The objective of this thesis is to locate pitch period cycles on a cycle-by-cycle basis. The complexity in identifying pitch cycles stems from the highly irregular nature of human speech. Dynamic programming is used to combine two sources of information for pitch period marking. One source of information is the "local" information corresponding to the location …


Developing A Sensing System For The Measurement Of Oxygen Concentration In Liquid Pb-Bi Eutectic: Quarterly Progress Report (July 1 – Sept. 30, 2004), Yingtao Jiang, Bingmei Fu Sep 2004

Developing A Sensing System For The Measurement Of Oxygen Concentration In Liquid Pb-Bi Eutectic: Quarterly Progress Report (July 1 – Sept. 30, 2004), Yingtao Jiang, Bingmei Fu

Transmutation Sciences Materials (TRP)

Dr. Jiang Ma and Mr. Xiaolong Wu worked in LANL between July 1 and Sept. 15 to conduct the experiment. Test of the corrosion of different materials in LBE was performed. The influence of the process of gas introduction to the LBE was studied. Data analysis work was performed based on accumulated data. In the same time, progress has been made in the simulation for transport in oxygen mixing, and one paper was presented in a conference. Another paper was composed and submitted to IEEE International Symposium of Circuits and Systems for the track Chemical Sensors. Preparation of a paper …


Development Of A Systems Engineering Model Of The Chemical Separations Process: Final Report, Yitung Chen, Sean Hsieh Sep 2004

Development Of A Systems Engineering Model Of The Chemical Separations Process: Final Report, Yitung Chen, Sean Hsieh

Separations Campaign (TRP)

The whole chemical separation process is complex to the point that definitely requires certain level of systematic coordination. To perform smoothly and meet the target extraction rates among those processes, this research proposed a general-purpose systems engineering model.

A general purposed systems engineering model, Transmutation Research Program System Engineering Model Project (TRPSEMPro), was developed based on the above design concept. The system model includes four main parts: System Manager, Model Integration, Study Plan, and Solution Viewer. TRPSEMPro can apply not only to chemical separation process, but also a general system model.

Software engineering and Object Oriented Analysis and Design (OOA&D) …


Development Of A Systems Engineering Model Of The Chemical Separations Process, Yitung Chen, Sean Hsieh Sep 2004

Development Of A Systems Engineering Model Of The Chemical Separations Process, Yitung Chen, Sean Hsieh

Separations Campaign (TRP)

The whole chemical separation process is complex to the point that definitely requires certain level of systematic coordination. To perform smoothly and meet the target extraction rates among those processes, this research proposed a general-purpose systems engineering model.

A general purposed systems engineering model, Transmutation Research Program System Engineering Model Project (TRPSEMPro), was developed based on the above design concept. The system model includes four main parts: System Manager, Model Integration, Study Plan, and Solution Viewer. System Manager supervises all the case (problem) creation, and functionality definition. Model Integration identifies chemical extraction processes and their execution sequence. Study Plan is …


High Temperature Heat Exchanger Project: Quarterly Progress Report July 1, 2004 Through September 30, 2004, Anthony Hechanova Sep 2004

High Temperature Heat Exchanger Project: Quarterly Progress Report July 1, 2004 Through September 30, 2004, Anthony Hechanova

Publications (NSTD)

UNLV hosted a meeting on NHI Materials and Heat Exchanger Design on Monday, May 17. Paul Pickard (Sandia National Lab) and Bill Corwin (Oak Ridge National Lab) facilitated the meeting. The purpose of the meeting was to summarize the hydrogen materials and heat exchanger requirements and priorities for UNLV staff and their collaborators to support the research proposal solicitation for the UNLV Research Foundation HTHX program. Attendance was heavier than anticipated and required a change of venue to accommodate the crowd of over 30.


Standard For Cold-Formed Steel Framing – Prescriptive Method For One And Two Family Dwellings, 2001 Edition (With 2004 Errata), American Iron And Steel Institute Sep 2004

Standard For Cold-Formed Steel Framing – Prescriptive Method For One And Two Family Dwellings, 2001 Edition (With 2004 Errata), American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.


Optical Filter Elements And Methods Of Making And Using Same, Michael A. Scobey, Lucien P. Ghislain, Dennis J. Derickson, Loren F. Stokes Sep 2004

Optical Filter Elements And Methods Of Making And Using Same, Michael A. Scobey, Lucien P. Ghislain, Dennis J. Derickson, Loren F. Stokes

Electrical Engineering

Optical filter elements and optical systems comprise optically mismatched etalons and optically mismatched stacked, optically coupled etalons that are directly optically coupled, at least one of the etalons or stacked, optically coupled etalons comprising first and second selectively transparent thin film mirror coatings on opposite surfaces of a bulk optic. The optically mismatched etalons can be configured to selectively pass single passbands. The disclosed optical systems optionally comprise other devices optically coupled to the optically mismatched etalons and optionally mismatched stacked, optically coupled etalons.


Preliminary Report On September 28, 2004 Parkfield Earthquake, Rakesh K. Goel, Charles Chadwell Sep 2004

Preliminary Report On September 28, 2004 Parkfield Earthquake, Rakesh K. Goel, Charles Chadwell

Civil and Environmental Engineering

A strong earthquake of magnitude 6.0 (Mw) struck the Central Coast of California at 10:15:24 AM PST (17:15:24 UTC) on Tuesday, September 28, 2004. The epicenter (Figure 1) was 11 km (7 mile) SSE of Parkfield, at a depth of approximately 8 km (5 mile). The main shock was followed by a strong aftershock of magnitude 5.0 roughly four minutes later. As expected, numerous smaller aftershocks continue to strike to epicentral region. At the time of this report, no injuries have been reported and the damage is light, mostly limited to nonstructural damage. This preliminary report presents …


Integrated Vlsi Potentiostat For Cyclic Voltammetry In Electrolytic Reactions, Harpreet S. Narula, John G. Harris Sep 2004

Integrated Vlsi Potentiostat For Cyclic Voltammetry In Electrolytic Reactions, Harpreet S. Narula, John G. Harris

Electrical and Computer Engineering Faculty Research & Creative Works

This paper describes a CMOS integrated potentiostatic control circuit. The design maintains a constant bias potential between the reference and working electrodes for an amperometric chemical sensor. A technique of converting input currents into time for amperometric measurements is proposed. Redox currents ranging from IpA to 200nA can be measured with a maximum non-linearity of ±0.1% over this range. The design can be used to generate a cyclic voltammogram for an electrochemical reaction by sweeping the voltages across the range specified by the user. Analog inputs are processed, and digital outputs are generated without requiring a power-hungry A/D converter. A …