Physical Sciences and Mathematics Commons^™

On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Year 1, Peter J. Popp, Sajal S. Pokharel, Gary A. Bishop, Donald H. Stedman

Fuel Efficiency Automobile Test Publications

No abstract provided.

The Window Distribution Of Multiple Tcps With Random Loss Queues, Archan Misra, Teunis Ott, John Baras

Research Collection School Of Computing and Information Systems

Two approximate techniques for analyzing the window size distribution of TCP flows sharing a RED-like bottleneck queue are presented. Both methods presented first use a fixed point algorithm to obtain the mean window sizes of the flows, and the mean queue length in the bottleneck buffer. The simpler of the two methods then uses the ‘square root formula’ for TCP; the other method is more complicated. More often than not, the simpler method is slightly more accurate; this is probably due to the fact that window sizes of the different flows are negatively correlated.

Systemic Environmental Analysis Of The Legal Mechanisms For Controlling Air Pollution In The Las Vegas Valley, Richard Little

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study examines the air pollution control structure for the Las Vegas Valley. A System Dynamics computer model was created that represents the structure of the real world system for controlling air pollution, in order to examine how the current air pollution control system might behave in the future.

Mineral Paragenesis And Ore Fluids At The Turquoise Ridge Gold Deposit, Nevada, Michiko Shigehiro

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this study, mineral assemblages and related fluid inclusions at the Turquoise Ridge Carlin-type gold deposit were examined to answer the following questions: (1) What is the ore-stage mineral paragenesis? (2) At what pressures and temperatures did the deposits form? (3) What are the sources of ore fluids?

Pyrite with gold, jasperoid quartz, stibnite, orpiment, realgar, and calcite were successively deposited at Turquoise Ridge. Microthermometric data and isotopic ratios of inclusion fluids in ore-related minerals indicate entrapment of multiple generations of fluids in pre-ore, ore-, and late-ore stage minerals. Primary fluid inclusions in an ore-stage jasperoid quartz crystal have salinities …

Alteration Associated With Gold Deposition At The Getchell, Carlin-Type Gold Deposit, North-Central Nevada, Tracy Lynn Cail

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alteration at the Getchell deposit was examined to determine the effects of ore-bearing fluids on host lithologies and the relationship between K-bearing alteration minerals and Au deposition. The geochemistry of unaltered to highly altered and mineralized rocks from the Getchell deposit was quantified for 54 samples collected along 14 transects in calcareous siltstone, carbonaceous limestone, and a rhyodacitic dike. Each transect was collected along a single homogeneous bed that could be followed from visibly unaltered waste rock into high-grade ore.

Calculated elemental gains and losses record an increase in the concentrations of Au, Hg, Sb, Se, Si, Te, Tl, and …

Implementation Of Speech Recognition Software For Text Processing: An Exploratory Analysis, Sean P. Abell

Theses and Dissertations

The rationale behind implementing new information technologies is often to gain productivity improvements associated with the substitution of machinery for labor. However, the literature shows little direct evidence of a positive relationship between information technology investment and subsequent productivity benefits. This thesis reports on the examination into the productivity implications of implementing speech recognition software in a text processing environment. More specifically, research was conducted to compare text processing speeds and error rates using speech recognition software versus the keyboard and mouse. Of interest was the time required to input and proofread text processing tasks as well as the number …

A Numerical Simulation Of A Carbon Black Suspension Cell Via A Time-Reversed, Double Layer Compute Algorithm, Gregg T. Anderson

Theses and Dissertations

A numerical simulation of a carbon black suspension cell is explored which models a laser-induced plasma within a liquid ethanol medium of approximately 1 mm thickness. The simulation model assumes a laser pulse with a pulse width of approximately 9 nsecs propagating in the left-to-right direction striking the front surface of the medium and focusing to a spot within the liquid volume. When the energy density within a given irradiated volume is sufficiently high, it ignites the carbon particles and generates a large number of free electrons, i.e., a plasma. The plasma couples with the in-coming laser energy on a …

Towards A Game Theory Model Of Information Warfare, David A. Burke

Theses and Dissertations

The repeated game of incomplete information model, a subclass of game theory models, was modified to include aspects of information warfare. The repeated game of incomplete information model was first developed to analyze nuclear weapons disarmament negotiations. The central role of information in this model suggested its applicability to IW, which focuses on the defense and acquisition of information. A randomized experimental design was utilized to determine how people behave in a laboratory IW setting and to test the IW game model's basic predictions. The impact of experience and learning on IW performance was also assessed during the experiment. IW …

Network Security Versus Network Connectivity: A Framework For Addressing The Issues Facing The Air Force Medical Community, Franklin E. Cunningham Jr.

Theses and Dissertations

The Air Force has instituted Barrier Reef to protect its networks. The Air Force medical community operates network connections that are incompatible with Barrier Reef. To overcome this problem, OASD(HA) directed the Tri-Service Management Program Office (TIMPO) to develop an architecture that protects all military health systems and allows them to link with all three services and outside partners. This research studied the underlying networking issues and formed a framework based on data from network experts from the Air Force's medical centers and their base network organizations. The findings were compared TIMPO and a composite framework was developed that more …

Power, Performance, And Perception (P3): Integrating Usability Metrics And Technology Acceptance Determinants To Validate A New Model For Predicting System Usage, Alan P. Fiorello

Theses and Dissertations

Currently, there are two distinct approaches to assist information technology managers in the successful implementation of office automation software. The first approach resides within the field of usability engineering, while the second approach is derived from the discipline of management information systems (MIS). However, neither approach has successfully produced conclusive evidence that explains what characteristics facilitate system use as well as influence user acceptance of the system. This study reports on the validity of a new model, entitled the Power, Performance, Perception (P3) model, that links the constructs of usability engineering to user acceptance. Additionally, speech recognition software (SRS) was …

Evaporation Of Jet Fuels, Charles Eric Hack

Theses and Dissertations

Determining the fate and transport of JP-8 jet fuel is a complex and important problem. As part of the startup procedures for jet engines, fuel is passed through aircraft engines before combustion is initiated. Because of the extremely low temperatures at northern tier Air Force bases, the unburned fuel does not evaporate readily and may come into contact with ground crew. To determine the amount and duration of contaminant contact, the evaporation of the emitted fuel must be modeled. The amount and composition of the fuel upon reaching the ground crew may be determined by droplet evaporation models that have …

Information System Incidents: The Development Of A Damage Assessment Model, Mark D. Horony

Theses and Dissertations

Information system (IS) incidents are on the rise. With low manning and undertrained information security specialists it is difficult for organizations to stop IS incidents from occurring. Once an incident has occurred it is the IS manager's responsibility to ensure that a full and accurate damage assessment has been accomplished. However, most IS managers lack the necessary tools to assess the damage from an incident. This exploratory thesis developed an IS incident damage assessment model (DAM) that can be part of the IS manager's tool kit. During the development of the model, it became apparent that the model was supported …

Application Of The Interaction Picture To Reactive Scattering In One Dimension, Michael J. Maclachlan

Theses and Dissertations

The interaction picture is used together with the channel-packet method in a new time-dependent approach to compute reactive scattering matrix elements. The channelpacket method enables the use of the interaction picture for computing reactive S-matrix elements by splitting the computational effort into two parts. First, asymptotic reactant and product wavepackets are individually propagated into the interaction region of the potential to form Moller states. The interaction picture, in contrast to the usual Schrödinger picture of quantum mechanics, is so constructed that a wavefunction that experiences no change in potential (that is, a free-particle wavefunction) remains always fixed, with no translation …

Molecular-Dynamics Study Of Phase Transitions In Alkali Azides, M. M. Ossowski, John R. Hardy, R. W. Smith

John R. Hardy Papers

An account is presented of our studies of the order-disorder phase transitions in KN₃, RbN₃, and CsN₃. These are based on parameter-free interionic potentials based on the Gordon-Kim modified electron-gas formalism extended to molecular ions. We performed static structural relaxations and supercell molecular dynamics and predicted with reasonable accuracy the temperatures for the onset of the transitions. In particular, we address the question of how the N₃^- ions reorient to yield the transitions. We found the existence of NaCl-type high-temperature phases in disordered KN₃ and RbN₃ and argue that this …

Thermal Degradation Of Blends Of Polystyrene And Poly(Sodium 4-Styrenesulfonate) And The Copolymer, Poly(Styrene-Co-Sodium 4-Styrenesulfonate), Qiang Yao, Charles Wilkie

Chemistry Faculty Research and Publications

The thermal degradation of blends and copolymers of styrene with styrenesulfonic acid has been studied using thermogravimetric analysis, TGA/FTIR, and cone calorimetry. The blends have enhanced thermal stability relative to virgin polystyrene but there is no enhancement in thermal stability for the copolymers. Apparently, it is necessary to have adjacent sulfonic acid groups in order to permit the formation of a graphite-like char which can provide thermal protection to the polymer. It is necessary to have a good match in degradation temperatures of the two components if one is to have significantly enhanced thermal stability.

Measurement Of The B0B̅0 Oscillation Frequency Using L-D*+ Pairs And Lepton Flavor Tags, T. Affolder, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration

Kenneth Bloom Publications

The oscillation frequency Δm_d of B⁰B̅⁰ mixing is measured using the partially reconstructed semileptonic decay B̅⁰→l^- ν̅ D^*+X. The data sample was collected with the CDF detector at the Fermilab Tevatron collider during 1992–1995 by triggering on the existence of two lepton candidates in an event, and corresponds to about 110 pb^-1 of p̅p collisions at √s =1.8 TeV. We estimate the proper decay time of the B̅⁰ meson from the measured decay length and reconstructed momentum of the l^-D^*+ system. The charge of …

Optimal Power Allocation In Cdma Forward Link Using Dependency Between Pilot And Traffic Channels, Seung Jong Park, Dongwoo Kim, Chang Yeon Kim

Computer Science Faculty Research & Creative Works

This paper shows a new method for minimizing the transmit power on CDMA forward link channels. Different from previous works, the proposed method uses the dependency that exists between the respective signal qualities of the pilot channel and traffic channels. Since present CDMA forward link exploits coherent demodulation with continuously transmitting pilot signals, the stronger the pilot channel is, the less traffic power may be required while the same transmission quality is maintained. With laboratory tests, the dependency is graphed. And then an optimal pilot signal quality is found, which minimizes the total transmit power. Considering various mobile environments, -10 …

Mining Multiple-Level Association Rules In Large Databases, Jiawei Han, Yongjian Fu

Computer Science Faculty Research & Creative Works

A top-down progressive deepening method is developed for efficient mining of multiple-level association rules from large transaction databases based on the Apriori principle. A group of variant algorithms is proposed based on the ways of sharing intermediate results, with the relative performance tested and analyzed. The enforcement of different interestingness measurements to find more interesting rules, and the relaxation of rule conditions for finding `level-crossing' association rules, are also investigated in the paper. Our study shows that efficient algorithms can be developed from large databases for the discovery of interesting and strong multiple-level association rules.

Computational Geometry Column 36, Joseph O'Rourke

Computer Science: Faculty Publications

Two results in "computational origami" are illustrated.

Implementing Sap R/3 At The University Of Nebraska, T. Sieber, Keng Siau, Fiona Fui-Hoon Nah, M. Sieber

Research Collection School Of Computing and Information Systems

In April 1995, I asked four Nebraskans from the private sector and four senior people of the University to review the administrative processes of the University of Nebraska. In the appointment letter for this Task Force, I noted that many current administrative processes need to be examined to improve quality and productivity.

A Perturbation Of A Periodic Hamiltonian System, Gregory S. Spradlin

Publications

No abstract provided.

Effects Of Watershed Land Use On The Benthic Macroinvertebrate Assemblages In Ridge And Valley Streams In Chattanooga, Tennessee, Paul Leiper Freeman

Masters Theses and Doctoral Dissertations

A total of 20 sites in five Ridge and Valley streams located in Chattanooga, Tennessee were sampled May 8, 1998 to June 18, 1998 using quantitative and qualitative macroinvertebrate sampling techniques. All streams sampled were part of the Tennessee River drainage system and eventually contribute to Nickajack Reservoir. The 20 sites were second to fourth order streams with drainage areas of 3.8 to 46.9 (km2) and elevations of 195 to 232 (m). Sites with different percentages of agricultural, urbanized and forested land-use were selected to best evaluate the resulting impacts of urbanization and other anthropogenic activities on the invertebrate community …

Wildlife-Caused Losses For Producers Of Channel Catfish Ictalurus Punctatus In 1996, Alice P. Wywialowski

United States Department of Agriculture Wildlife Services: Staff Publications

The National Agricultural Statistics Service surveyed by telephone and mail in January and February 1997 all known producers of channel catfish Ictalurus punctatus to acquire current information about wildlife-caused losses in calendar year 1996. Many producers tried to prevent wildlife-caused losses of their catfish by shooting (57%), vehicle patrol (55%), or frightening (36%), at an estimated cost of >$5 million. Yet, 69% of catfish produces cited some wildlife-caused losses. Birds were most frequently cited as a cause of losses, and double-crested cormorants Phalacrocorax auritus was the species cited most frequently (53%). The next most frequently cited bids were herons Ardea …

Evaluation Of Sampling Methodologies For Assessing Fish Species Richness In Ridge And Valley Streams In Chattanooga, Tennessee, Evan Robertson Crews

Masters Theses and Doctoral Dissertations

I evaluated the adequacy of different electrofishing approaches for estimating species richness in small Ridge and Valley streams. My study objectives were to determine the effects of the sampling season, reach length, habitat sequences surveyed, and sampling intensity on estimates of fish species richness. Fish assemblages were sampled at 18 sites across five streams in the Chattanooga, Tennessee area, May-June (spring) and July-August (summer) 1998. Reach lengths ranged from 103 to 278 m (30 to 61 times the mean stream width [MSW]). At each site, fish were collected using one or two backpack electrofishers within habitat-specific enclosures (riflle-run or pool). …

What Else Do We Forget To Tell Our Teachers?: A Response To Dancis, Stephen Sproule

Humanistic Mathematics Network Journal

No abstract provided.

Interior-Point Methods And Modern Optimization Codes, Goran Lesaja

Mathematical Sciences: Faculty Publications

During the last fifteen years we have witnessed an explosive development in the area of optimization theory due to the introduction and development of interior-point methods. This development has quickly led to the development of new and more efficient optimization codes. In this paper, the basic elements of interior-point methods for linear programming will be discussed as well as extensions to convex programming, complementary problems, and semidefinite programming. Interior-point methods are polynomial and effective algorithms based on Newton 's method. Since they have been introduced, the classical distinction between linear programming methods, based on the simplex algorithm, and those methods …

Lattice-Stiffening Transition In Copolymer Films Of Vinylidene Fluoride (70%) With Trifluoroethylene (30%), C.N. Borca, Shireen Adenwalla, Jaewu Choi, P.T. Sprungerr, Stephen Ducharme, Lee Robertson, S.P. Palto, Jianglai Liu, Matt Poulsen, V.M. Fridkin, H. You, Peter A. Dowben

Peter Dowben Publications

We report the discovery of a compressibility phase transition at 160 K in crystalline copolymer films of vinylidene fluoride ( 70%) with trifluoroethylene ( 30%). This phase transition is distinct from the known bulk ferroelectric-paraelectric phase transition at 353 K and surface ferroelectric phase transition at 295 K. The new phase transition is characterized by an increase in the effective Debye temperature from 48 to 245 K along the 〈010〉 direction as the temperature falls below 160 K. This phase transition is evident in neutron scattering, x-ray diffraction, angle-resolved photoemission, and in the dipole active phonon modes in electron energy-loss …

Surface Enhanced Raman Spectroscopic Study Of Scn- Adsorbed At The Copper And Gold Nanowire Arrays, Jian-Lin Yao, Guo-Ping Pan, Kuan-Hong Xue, Yong Xie, Jing Tang, Bin Ren, Dong-Mei Sun, Bing-Wei Mao, Zhong-Qun Tian

Journal of Electrochemistry

Two-dimensional arrays of Cu and Au nanowires have been fabricated by template synthesis method, using the anodic aluminum oxidation films as the template. The morphology of the nanowire array was monitored by atomic force microscope (AFM) in the dissolution processes of the alumina film. Based on the probe molecule strategy, the spectral feature of SCN^- adsorbed at the Cu and Au nanowires with different diameters has been investigated by surface enhanced Raman spectroscopy (SERS). The results reveal that the intensity of the SERS bands depends on the length of the exposed nanowires. The C≡N stretching vibration frequency (ν_{CN …}

The Electrochemical Behaviors Of Superoxide Dismutase At Promoter Modified Gold Electrode, Xia-Qin Wu, Xiao-Yun Meng, Zhe-Su Wang, Zong-Rang Zhang

Journal of Electrochemistry

The electron-transfer process of superoxide dismutase was investigated by cyclic voltammetry at the 4,4'-dithiodipyridine, L-cysteine, histidine and arginine modified gold wire electrodes repectively. The quasi-reversible behavior was observed at L-cysteine modified gold electrode. An irreversible electrochemical behavior has been observed at hisdinine modified gold wire electrode.

Aes Multi-Layer Structural Analysis Of Si Based Anodic Porous Alumina Films And Studies On Its Formation Mechanism, Jun-Hui Wu, Jian-Ping Zou, Qing Zhu, Xi-Mao Bao

Journal of Electrochemistry

400 nm aluminum films were deposited onto a p-type, 0.5 Ω·cm,〈100〉oriented silicon wafers using electron beam evaporation technique. Then, the wafers was immersed in 15 wt% H₂SO₄ for porous-type over-anodization under a constant voltage of DC 60V. During the anodization,the temperature of the electrolyte was maintained at 0 ℃. The obtained samples were investigated by means of transmission electron microscopy, scanning electron microscopy, and AES depth profile for multi-layer structural information. In addition, the basic anodic formation mechanism of the Si-based aluminum films was brielfly discussed.