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A Comparative Analysis Of Viable Solar Thermal Technologies For Solar Field Development And Commercialization, Sean M. Crawford May 1996

A Comparative Analysis Of Viable Solar Thermal Technologies For Solar Field Development And Commercialization, Sean M. Crawford

UNLV Theses, Dissertations, Professional Papers, and Capstones

Diminishing fossil fuels and concerns about the quality of the environment has lead the recent drive to establish a commercialized solar field in Southern Nevada. The competing solar thermal technologies for the Solar Enterprise Zone (SEZ) are Parabolic Dish-Stirling, Central Receiver Power Towers, and Parabolic Trough Systems. It is important to compare the technologies based on the guidelines set by the Corporation for Solar Technology and Renewable Resources. The variables weighted are solar conversion performances, initial capital investment, operation and maintenance costs, water and land use, and electricity production costs. All technologies have been proven to viable power sources and …

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Residence Time Of Groundwater Issuing From The South Rim Aquifer In The Eastern Grand Canyon, Jim Fitzgerald May 1996

Residence Time Of Groundwater Issuing From The South Rim Aquifer In The Eastern Grand Canyon, Jim Fitzgerald

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the eastern Grand Canyon, secondary porosity created by north trending faults, folds, and breccia pipes, facilitates groundwater flow through the South Rim carbonate aquifer. Springs associated with the South Rim Aquifer have low 3H concentrations, [Ca2+]/[Mg2+] rations close to unity, and variable uranium concentrations. For a geochemical comparison, springs are subcategorized on the basis of geology and discharge. Type I springs are associated with high-angle normal faults and have high discharge rates. These springs discharge Ca2+ - Mg2+, HCO3- waters, have 3H concentrations <2 TR, and 234U/238U activity …

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Report Of Significant Findings--Las Vegas Bay/Boulder Basin Investigations, James F. Labounty, Michael Horn, Bureau Of Reclamation Apr 1996

Report Of Significant Findings--Las Vegas Bay/Boulder Basin Investigations, James F. Labounty, Michael Horn, Bureau Of Reclamation

Publications (WR)

Field sampling was carried out between 0830 and 1500 beginning at the confluence of Las Vegas Wash and the Inner Las Vegas Bay. Ten (10) locations were sampled, each in a similar manner. Locations of sampling stations are in line from the Wash-Bay confluence to a point midway between Saddle and Black Islands. In addition, sampling was done at a location midway between Sentinel Island and the base of Fortification Hill, and at the buoy line in front of Hoover Dam. Sampling stations are labeled from LV01, at Wash-Bay confluence, to LV17 at Hoover Dam. A significant data collection point …

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Innovations In Reuse, Lisa R. Osorio Apr 1996

Innovations In Reuse, Lisa R. Osorio

UNLV Theses, Dissertations, Professional Papers, and Capstones

Material reuse benefits all sectors in the community by decreasing the amount of reusable solid waste that is discarded. It increases the resources available for various programs and builds partnerships with educators, and businesses to support and promote reuse programs that will improve the quality of life in areas in which they operate. Several areas of the country currently have reuse programs that focus on several areas of reuse. Successful projects in several cities have focused on such areas as reuse for education, the arts, or other nonprofit activities. These sustainable programs have benefited other communities and should serve as …

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An Experimental Technique In Lowering Total Dissolved Solids In Wastewater, Aaron Crotts Apr 1996

An Experimental Technique In Lowering Total Dissolved Solids In Wastewater, Aaron Crotts

UNLV Theses, Dissertations, Professional Papers, and Capstones

An experimental method for lowering total dissolved solids in wastewater. This thesis project has been undertaken by Aaron Crotts in partial fulfillment of requirements for the degree of Bachelor of Arts in Environmental Studies. The problem undertaken in this thesis is to apply an experimental technique in wastewater treatment in hopes of reducing the total dissolved solids. Total dissolved solids consist of various dissolved ions in water such as calcium, magnesium, sulfur and sodium. In looking at one industry in particular a local Ice Cream manufacture, the problem with total dissolved solids is evident because of their manufacturing process, an …

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The Barriers Present In More Developed Countries And Less Developed Countries Slowing The Implementation Of Substainability, Luke Giovine Apr 1996

The Barriers Present In More Developed Countries And Less Developed Countries Slowing The Implementation Of Substainability, Luke Giovine

UNLV Theses, Dissertations, Professional Papers, and Capstones

In 1996 the natural resource base of the world is being depleted at a rate far below the sustainable level. This is very evident in less developed countries (IDC), where raw limited natural resources are being poorly utilized and/or exported to more developed countries (MDC). The More Developed Countries such as the United States, Japan, and Germany use a high amount of natural resources and energy to maintain their material Standard Of Living (SOL), and this is at rates above what their own country can sustain with its own natural resources within its own borders. Both MDC's and LDC's are …

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An Analysis Of Remediation Alternatives In An Attempt To Establish An Effective Hydrocarbon-Contaminated Soils Remediation Program At The Yucca Mountain Site Characterization Project (Ymp), Marc A. Gonzales Apr 1996

An Analysis Of Remediation Alternatives In An Attempt To Establish An Effective Hydrocarbon-Contaminated Soils Remediation Program At The Yucca Mountain Site Characterization Project (Ymp), Marc A. Gonzales

UNLV Theses, Dissertations, Professional Papers, and Capstones

An analyses, of six (6) soil remediation alternatives was completed in attempt to establish an effective hydrocarbon-contaminated soils remediation program at the Yucca Mountain Site Characterization Program (YMP). The remediation alternatives analyzed included: no remediation, on-site incineration, off-site incineration, in-situ .bioremediation, ex-situ bioremediation, and excavation and disposal. Variables considered in the evaluation process included cost of contaminated soil transportation, treatment costs, future liability, and success of remediating the contaminated soils to below regulatory thresholds. The analysis concluded in the recommendation of an on-site ex-situ bioremediation treatment facility (BTF) to remediate hydrocarbon-contaminated soils at the YMP. The selection was based on …

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Auger Resonant Raman Spectroscopy Used To Study The Angular Distributions Of The Xe 4d5/2 → 6p Decay Spectrum, B. Langer, N. Berrah, A. Farhat, Oliver Hemmers, J. Bozek Apr 1996

Auger Resonant Raman Spectroscopy Used To Study The Angular Distributions Of The Xe 4d5/2 → 6p Decay Spectrum, B. Langer, N. Berrah, A. Farhat, Oliver Hemmers, J. Bozek

Environmental Studies Faculty Publications

The Auger resonant Raman effect can be used as a method to eliminate natural lifetime broadening in resonant Auger spectra. We have coupled this method with high-resolution photons from the Advanced Light Source to study angular distributions and decay rates of the Xe4d5/2→6p resonant Auger lines. The angular distribution parameters β of almost all possible final ionic 5p4(3P, 1D, 1S)6p states have been determined. Our data, which remove the discrepancy between previous lower-resolution experimental results, are compared to different theoretical results.

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Unlv Magazine, Barbara Cloud, Donna Mcaleer Apr 1996

Unlv Magazine, Barbara Cloud, Donna Mcaleer

UNLV Magazine

No abstract provided.

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A Statistical Approach To Assess The Efficiency Of Bioremediation Methods, Cynthia Lynn Glickman Jan 1996

A Statistical Approach To Assess The Efficiency Of Bioremediation Methods, Cynthia Lynn Glickman

UNLV Retrospective Theses & Dissertations

There are a number of Superfund sites in which biotreatability studies are used to assess whether an addition of some surfactants have a positive effect on the rates of biodegradation of PAH concentrations when compared to a control. U.S. EPA, in many situations, will require a minimum of 40% reduction over the control before approving the bioremediation method. Typically, samples of PAH concentrations are collected from an experiment involving the bio-treatment and the control conditions. The percent reduction is calculated by the formula: {dollar}\rm{\=x\sb1-\=x\sb2\over x\sb1}\times100\%.{dollar}; If the above percent reduction exceeds 40%, then the biotreatment is considered to be effective. …

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An Object-Oriented Modeling Approach To Build Data Communication Model, Wuqing Xu Jan 1996

An Object-Oriented Modeling Approach To Build Data Communication Model, Wuqing Xu

UNLV Retrospective Theses & Dissertations

The problem of data communications between process units within a telecommunication network based on OSI's standard seven layer Reference Model is addressed. In this thesis, we expose the generic aspect of protocol implementation as an object-oriented conceptual model emphasizing on the dynamic aspects of the objects involved while we explore both aspects, namely, static and dynamic aspects. A data communication model is proposed; Through the development of the conceptual model, we can capture the crucial aspects of network system and omit others. In developing the conceptual model for data communication, we apply object-oriented modeling principles to explore the potential elements …

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The Role Of Interference In Metacognitive Monitoring, Katherine M Jacobi Jan 1996

The Role Of Interference In Metacognitive Monitoring, Katherine M Jacobi

UNLV Retrospective Theses & Dissertations

Recent advancements in neuropsychology have initiated theoretical advancements in cognitive psychology, particularly concerning the constructs of interference and metacognition. These constructs share similar cognitive functioning and this study investigated the relationship between them. It was expected that students with higher monitoring ability would demonstrate lower susceptibility to interference. Students from undergraduate Educational Psychology classes were administered three tests: two measures of interference, and one measure of metacognitive monitoring ability. Variables from the Wisconsin Card Sort Test (WCST) and the Stroop Color and Word Test (SCWT) measured susceptibility to interference. A monitoring task applied to a math aptitude test was used …

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Evaluation Of An Alternative Statistical Decision Rule For Site Remediation, Bradley Donald Schultz Jan 1996

Evaluation Of An Alternative Statistical Decision Rule For Site Remediation, Bradley Donald Schultz

UNLV Retrospective Theses & Dissertations

A method proposed by the Environmental Protection Agency to optimize site remediation, called the CRG approach states that soil cleanup levels are typically misapplied on a point by point basis rather than on average. The effectiveness of the CRG approach will be evaluated for lognormal, exponential, uniform, and normally distributed data by first simulating data sets for each distribution. Next the CRG approach will be applied to the simulated data sets. Finally, the results of the CRG approach will be analyzed.

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Colloidal Interactions Of Thorium, Frezewd Haile-Meskel Jan 1996

Colloidal Interactions Of Thorium, Frezewd Haile-Meskel

UNLV Retrospective Theses & Dissertations

Some organic and inorganic colloids have a strong affinity to bind radionuclides, and therefore, enhance their mobility. This study attempted to determine the interactions of thorium with colloidal humic acid and colloidal silica under various aqueous conditions and organic carbon from Blue point, Muddy, and Rogers Springs. A colloidal distribution study was done in spiked Lake Tahoe and Mono Lake samples. Plutonium was studied as an example for other radionuclides. Based on these studies, both thorium and plutonium were associated mostly with particles smaller than 0.45{dollar}\mu{dollar}m. Humic acid and organic carbon were found to have little influence on thorium speciation …

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Describing The Elephant: Multiple Perspectives In New York City's Watershed Protection Conflict, Krystyna Anne Stave Jan 1996

Describing The Elephant: Multiple Perspectives In New York City's Watershed Protection Conflict, Krystyna Anne Stave

Public Policy and Leadership Faculty Research

New York City's efforts to avoid filtration mandated by the 1986 Safe Drinking Water Act Amendments and the 1989 Surface Water Treatment Rule have generated considerable controversy. Since the conflict began in 1990, a spectrum of stakeholder groups has emerged, representing land owners, sport fishermen, businesses, environmental groups, developers, and watershed communities. What was originally defined by New York City water supply managers as a scientific problem--identifying sources of water quality degradation and preventing contaminants from entering the water supply system--now has broadened to include a diverse set of social and economic issues as well.

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A Self-Consistent Numerical Method For Simulation Of Quantum Transport In High Electron Mobility Transistor; Part 1: The Boltzmann-Poisson-Schrodinger Solver, Rahim Khoie Jan 1996

A Self-Consistent Numerical Method For Simulation Of Quantum Transport In High Electron Mobility Transistor; Part 1: The Boltzmann-Poisson-Schrodinger Solver, Rahim Khoie

Electrical & Computer Engineering Faculty Research

A self-consistent Boltzmann-Poisson-Schrödinger solver for High Electron Mobility Transistor is presented. The quantization of electrons in the quantum well normal to the heterojunction is taken into account by solving the two higher moments of Boltzmann equation along with the Schrödinger and Poisson equations, self-consistently. The Boltzmann transport equation in the form of a current continuity equation and an energy balance equation are solved to obtain the transient and steady-state transport behavior. The numerical instability problems associated with the simulator are presented, and the criteria for smooth convergence of the solutions are discussed. The current-voltage characteristics, transconductance, gate capacitance, and unity-gain …

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Multicasting In Generalized Class Networks, Carl Michael Lane Jan 1996

Multicasting In Generalized Class Networks, Carl Michael Lane

UNLV Retrospective Theses & Dissertations

A problem that we are experiencing in communication networks is the ability to efficiently multicast information to a group of network sites. Multicasting is defined as point to multipoint communications. Within a network, for example, we may want to send a message from one network site to five other network sites. This is an example of a multicasting operation; We are seeing an increased use of applications which blend not only data, but also voice, and video. Due to this increase in usage, we are experiencing a need to conserve network bandwidth and to avoid loading communication networks excessively. To …

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Topics In Combinatorics: A Statistical Application, Susan Diane Mccuistion Jan 1996

Topics In Combinatorics: A Statistical Application, Susan Diane Mccuistion

UNLV Retrospective Theses & Dissertations

The discrete math area known as combinatorics has specific applications in statistics. In this paper, the relationship between combinatorics and statistics will be explored. Major areas of concentration will include: generating functions, special combinatorial numbers and their use in statistics, and the specific relationship of these functions and numbers to some of the more common discrete distributions found in statistics.

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Ocrspell: An Interactive Spelling Correction System For Ocr Errors In Text, Eric Stofsky Jan 1996

Ocrspell: An Interactive Spelling Correction System For Ocr Errors In Text, Eric Stofsky

UNLV Retrospective Theses & Dissertations

In this thesis we describe a spelling correction system designed specifically for OCR (Optical Character Recognition) generated text that selects candidate words through the use of information gathered from multiple knowledge sources. This system for text correction is based on static and dynamic device mappings, approximate string matching, and n-gram analysis. Our statistically based, Bayesian system incorporates a learning feature that collects confusion information at the collection and document levels. An evaluation of the new system is presented as well.

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Feature Selection For Classification Of Medical Images Of Human Tissue For Cancer Recognition, Valeri V Tsarev Jan 1996

Feature Selection For Classification Of Medical Images Of Human Tissue For Cancer Recognition, Valeri V Tsarev

UNLV Retrospective Theses & Dissertations

A statistical pattern recognition system for ultrasound medical images of prostatic tissue for cancer has been proposed. Using the autocorrelation method, the correct size of a statistical sliding window for feature extraction was defined. Known texture discrimination features have been tested for effectiveness. Another set of discriminating features, based on edge value distribution, Fourier power spectrum and wavelet transform has been derived and investigated. The set can be used as an input to a neural net classifier.

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Data Integration With Data Warehousing And Data Mining In Database Environments, Gary Leon White Jan 1996

Data Integration With Data Warehousing And Data Mining In Database Environments, Gary Leon White

UNLV Retrospective Theses & Dissertations

The topics of data warehousing and data mining encompasses architectures, algorithms and tools for bringing together selected data from multiple databases or other information sources into a single repository called a data warehouse which is suitable for direct querying or analysis. The querying and analysis can be implemented with any of the data mining tools being developed. Data mining is the non-trivial extraction of implicit, previously unknown and potentially useful information from information sources; In this thesis, we will define a specific data warehousing architecture, its components and give an explanation of the responsibilities of the components in the data …

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Crisis Management And Its Impact On Destination Marketing, Whitney Blair Young Jan 1996

Crisis Management And Its Impact On Destination Marketing, Whitney Blair Young

UNLV Retrospective Theses & Dissertations

Crisis Management and Its Impact on Destination Marketing analyzes the crisis management procedures utilized by four specific Convention and Visitors Bureaus in a variety of disaster situations and locations across the United States. The crises studied are representative of both man-made and natural disasters, and occurred in destinations in which tourism plays a significant role. From these case studies, a comprehensive set of crisis management procedures was compiled for the benefit of Convention and Visitors Bureaus nationwide. Such standardized crisis management procedures will presumably contribute to a faster and more efficient recovery for any destination after a crisis, because they …

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Effect Of Unsaturated Zone Soil Moisture Content On Vapor Phase Pollutant Propagation In Controlled Laboratory Experiments, Joseph J Squire Jan 1996

Effect Of Unsaturated Zone Soil Moisture Content On Vapor Phase Pollutant Propagation In Controlled Laboratory Experiments, Joseph J Squire

UNLV Retrospective Theses & Dissertations

Experiments were conducted to assess and model the effects of unsaturated zone soil moisture content on vapor-phase pollutant propagation in a controlled setting. A two-dimensional sandtank was utilized for controlled vapor-phase experiments, with pollutant vapors of octane and diesel fuel introduced through a finely slotted source tube. Soil moisture content was varied from 0% to 10% by weight for octane experiments, and from 0% to 5% by weight for diesel fuel. The effects of introduced soil moisture on the transport of each pollutant vapor were observed via soil-gas sampling from access ports. Soil-gas samples were analyzed with FID gas chromatography …

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Acoustic Breakout From Fiberglass Ducts, Keith M Degner Jan 1996

Acoustic Breakout From Fiberglass Ducts, Keith M Degner

UNLV Retrospective Theses & Dissertations

Acoustical breakout is the transmission of sound through the walls of heating, ventilation, and air conditioning ducts. Equations for predicting the breakout from rectangular, circular, and oval sheet metal ducts have been published by the American Society of Heating, Ventilation, and Air Conditioning Engineers (ASHRAE); Recent advances in manufacturing techniques have led to the development of fiberglass lined sheet metal ducts, and ducts made from fiberglass ductboard. The equations presented by ASHRAE do not accurately predict the transmission loss from fiberglass ducts; This project involved testing of rectangular and circular sheet metal, lined fiberglass, and fiberboard ducts. The breakout transmission …

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Investigation Of Regional Flow Patterns In The Ash Meadows Groundwater Basin Of Southern Nevada Using Uranium Isotope Ratios, Dennis Edward Farmer Jan 1996

Investigation Of Regional Flow Patterns In The Ash Meadows Groundwater Basin Of Southern Nevada Using Uranium Isotope Ratios, Dennis Edward Farmer

UNLV Retrospective Theses & Dissertations

Uranium concentrations and {dollar}\rm\sp{234}U/\sp{238}U{dollar} isotope ratios were determined for over 100 springs, wells and surface waters in areas on and surrounding the historical nuclear weapons testing range in southern Nevada, the Nevada Test Site (NTS). Uranium concentrations were less than 2 {dollar}\mu{dollar}g/liter in the Spring Mountains, where ground water enters the system, and between 2.5 and 5 {dollar}\mu{dollar}g/liter in waters discharging from the major springs at Ash Meadows, Nevada and the Death Valley-Furnace Creek area of southeastern California. Slightly higher levels of dissolved uranium (6-15 {dollar}\mu{dollar}g/liter) were associated with the weathering of susceptible rocks and the concentration of ground water …

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Optimal Var Compensation On A Utility Transmission System, Douglas Earl Harshbarger Jan 1996

Optimal Var Compensation On A Utility Transmission System, Douglas Earl Harshbarger

UNLV Retrospective Theses & Dissertations

This paper presents a method for realizing power loss and reactive power flow reductions on an electrical power transmission system. The method determines the size and location of reactive power compensating capacitors. In the first phase, candidate busses (nodes) are identified by determining which substations are physically able to accommodate new capacitor and associated switching apparatus. Phase two employs an iterative search technique, the Western System Coordinating Council (WSCC) power flow program and heuristic inputs to choose the single buss most sensitive to real power loss reduction. Reactive power loss reduction and reactive power intertie flow are secondary factors also …

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Motor Starting With Shunt Capacitors: An Alternate Approach To Voltage Dip Control, Ravi Anantarao Managuli Jan 1996

Motor Starting With Shunt Capacitors: An Alternate Approach To Voltage Dip Control, Ravi Anantarao Managuli

UNLV Retrospective Theses & Dissertations

Induction motors are known to cause undesirable voltage dip because of high inrush current during starting, especially when fed from weak AC systems. For this reason, large motors are often started with reduced voltage. This thesis proposes full-voltage motor starting with shunt capacitors. Two types of capacitors are used: power factor correction capacitor and start capacitor. The start capacitor is determined to maximize the input impedance during starting in order to reduce the initial inrush current. The analysis shows that shunt capacitors improve the voltage dip and the motor acceleration significantly but introduce some level of waveform distortion during each …

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A Three-Dimensional Finite Element Model For Diagnostic Windfield Assessment, Zijiang Shi Jan 1996

A Three-Dimensional Finite Element Model For Diagnostic Windfield Assessment, Zijiang Shi

UNLV Retrospective Theses & Dissertations

A 3-dimensional model that calculates windfields over irregular terrain based on meteorological tower data has been developed. The governing equations of atmospheric motion, the finite element method and atmospheric boundary layer concept have been introduced. A surface model of the Nevada Test Site (NTS) has been generated from DEM files which contain elevation data, and a 3-D mesh has been generated. Initial estimates of the velocity field are developed by interpolating surface and upper level wind measurements. A diagnostic objective analysis technique is used to generate 3-D winds above the surface layer. This algorithm incorporates NTS tower field measurements to …

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Watchman Routes In The Presence Of Convex Obstacles, Rocky Joseph Lombardo Jan 1996

Watchman Routes In The Presence Of Convex Obstacles, Rocky Joseph Lombardo

UNLV Retrospective Theses & Dissertations

This thesis deals with the problem of computing shortest watchman routes in the presence of polygonal obstacles. Important recent results on watchman route problems are surveyed. An {dollar}O(n\sp3){dollar} algorithm for computing a shortest watchman route in the presence of a pair of convex obstacles is presented. Important open problems related to watchman route problems are discussed.

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A Critical Evaluation Of The Dolby Digital Compression Algorithm, David Andrew Ingbretsen Jan 1996

A Critical Evaluation Of The Dolby Digital Compression Algorithm, David Andrew Ingbretsen

UNLV Retrospective Theses & Dissertations

Dolby Digital, or AC-3, provides for the compression of high-quality audio signals at a bit rate of 384 kbps. for 5.1 audio channels. The purpose of this thesis is to conduct an analysis and evaluation of the AC-3 compression algorithm. The main conclusion is that AC-3 allocates too few bits to the upper frequency ranges. This conclusion is supported by two lines of argument. First, a comparison of the AC-3 perceptual coding model with known facts concerning the masking properties of sound reveals omissions in the AC-3 perceptual model that lead to loss of high frequency resolution. Second, a test …

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