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Tutte Polynomials Computable In Polynomial Time, J. G. Oxley, D. J.A. Welsh

Faculty Publications

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Labeling Graphs With A Condition At Distance 2, Jerrold R. Griggs, Roger K. Yeh

Faculty Publications

No abstract provided.

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Linear Theory Of Non-Neutral Plasma Equilibrium In A Tilted Magnetic Field, Ross L. Spencer, Grant W. Hart

Faculty Publications

A linear perturbation expansion has been found that allows the rapid and accurate calculation of the response of a non-neutral plasma to a tilted magnetic field. The results of the calculation have been found to agree with previous three-dimensional equilibrium calculations, and also to agree with Keinigs' [Phys. Fluids 24, 860 (1981)] calculation of zero-frequency resonances caused by magnetic field errors. This expansion also allows the perturbed velocity to be calculated. It is speculated that this perturbed flow may be related to the enhanced radial transport in a non-neutral plasma with a tilted magnetic field.

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Use Of Raman Spectroscopy In Characterizing Soft X-Ray Multilayers: Tools In Understanding Structure And Interfaces, Ming Cai, Qi Wang, David D. Allred, Larry V. Knight, Dorian M. Hatch, A. Reyes-Mena, Guizhong Zhang

Faculty Publications

Our group is studying the structure and interfaces of soft x-ray multilayers by various techniques including x-ray diffraction and Raman spectroscopy. Raman spectroscopy is particularly useful since it is sensitive to the identity of individual bonds and thus can potentially characterize the abruptness of interfaces in multilayers. Blocking interfacial mixing is very important in achieving and maintaining high reflectivity. We report our studies of the as-deposited and postannealed structure of Mo/Si and W/C multilayers. The Mo/Si system is probably the most widely studied multilayer currently because of its potential applications for soft x-ray projection lithography for the range of 13 …

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Adaptive Boundary Detection Using “Live-Wire” Two-Dimensional Dynamic Programming, William A. Barrett, Bryan S. Morse, Eric N. Mortensen, Jayaram Udupa

Faculty Publications

An adaptive boundary detection algorithm that uses two-dimensional dynamic programming is presented. The algorithm is less constrained than previous one-dimensional dynamic programming algorithms and allows the user to interactively determine the mathematically optimal boundary between a user-selected seed point and any other dynamically selected "free” point in the image. Interactive movement of the free point by the cursor causes the boundary to behave like a “live wire” as it adapts to the new minimum cost path between the seed point and the currently selected free point. The algorithm can also be adapted or customized to learn boundary-defining features for a …

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Drying Of Beulah-Zap Lignite, Karl S. Vorres, David L. Wertz, Vivak Malhotra, Yuhong Dang, J.T. Joseph, Ronald Fisher

Faculty Publications

Lignite dried in a stream of dry nitrogen at moderate temperatures (20-80-degrees-C) loses water in two distinguishable modes. The first mode represents about 80-85% of the loss of moisture. The second represents the other 15-20% lost under these conditions. The rate follows a unimolecular mechanism (like radioactive decay) for each mode. The activation energy for the first mode is close to the heat of vaporization of water. The rate is dependent upon the gas flow around the sample and the weight (or thickness) of the sample. Work at Amoco Oil Company indicated that the oil yield was higher for the …

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Examining An Assumption Of Linkage Between Lesson Planning And Implementation, Trena Wilkerson, Anthony J. Scheffler

Faculty Publications

It is often suggested that preservice teachers who are trained to develop a lesson plan will, with equal acumen, be able to implement that plan. The purpose of this study was to test this assumption. Twenty-six preservice teachers in an early childhood practicum developed and implemented a mathematics lesson plan. The lesson plans were evaluated according to specific criteria set forth in the National Council of Teachers of Mathematics' Curriculum and Evaluation Standards for School Mathematics using a weighted checklist. The implementation of each plan was also assessed using a Likert Scale reflective of similar criteria. A correlation between the …

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Approximation By Interval Bezier Curves, Thomas W. Sederberg, Rida T. Farouki

Faculty Publications

The interval Bezier curve, which, unlike other curve and surface approximation schemes, can transfer a complete description of approximation errors between diverse CAD/CAM systems that impose fundamentally incompatible constraints on their canonical representation schemes, is described. Interval arithmetic, which offers an essentially infallible way to monitor error propagation in numerical algorithms that use floating-point arithmetic is reviewed. Affine maps, the computations of which are key operations in the de Casteljau subdivision and degree-elevation algorithms for Bezier curves, the floating-point error propagation in such computations, approximation by interval polynomials, and approximation by interval Bezier curves are discussed.

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Species Of The Cretaceous Tree Fern Tempskya From Utah, William D. Tidwell, Naomi Hebbert

Faculty Publications

Nine species of the permineralized stems of Tempskya were investigated from the Lower Cretaceous Cedar Mountain and Burro Canyon Formations, and the lower Upper Cretaceous Dakota Formation in central and southeastern Utah. Tempskya jonesii, T. stichkae, and T. readii are new and are differentiated on the basis of the radial orientation of their dorsiventral stems, their internodal lengths, the lack of sclerenchyma in the inner cortex of T. jonesii, the three nearly continuous zones of sclerenchyma in the inner cortex off T. stichkae, and the completely sclerotic inner cortex of T. readii. Specimens of T. jonesii and T. minor were …

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Connectivity Of Submodular Functions, James Oxley, Geoff Whittle

Faculty Publications

The notion of connectivity for submodular functions was introduced by Cunningham. This paper relates the connectivity of such a function f to that of certain submodular functions which are derived from f. In particular, we prove a generalisation of the well-known matroid result that, for every element x of a connected matroid M, either the deletion or contraction of x from M is connected. © 1992.

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Recoil Effects And Cp Violation In Neutron Scattering, Vladimir Gudkov

Faculty Publications

The problem of the imitation of CP violation in neutron scattering is discussed. The thermal motion of nuclei cannot contribute to symmetry-violating effects. The influence of the nuclear depolarization due to neutron scattering is estimated.

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Interface Cavitation Damage In Polycrystalline Copper, Brent L. Adams, David P. Field

Faculty Publications

The authors acknowledge the support of the Office of Basic Energy Sciences of the United States Department of Energy. Determination of an interface damage function (IDF) from a stereological procedure similar to that presented by Hilliard is described. The mathematical and experimental simplicity of the method is utilized in measuring an IDF for polycrystalline copper crept at 0.6T sub m under uniaxial tension. Whereas previous work focused on a five parameter description of the local state of a grain boundary, the domain of the IDF is increased to eight degrees of freedom in the present study to include the complete …

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Viscoelastic Properties Of A Liquid-Crystalline Monomer And Its Dimer, Gregory A. Dilisi, Charles Rosenblatt, Anselm C. Griffin, Uma Hari

Faculty Publications

Quasielastic-light-scattering measurements are reported for a dialkoxyphenylbenzoate monomer and its dimer in their respective nematic phases. The splay and twist elastic moduli of the dimer are found to be nearly independent of molecular length. The dimer's bend modulus, however, shows an anomalous increase with decreasing temperature well below the nematic-isotropic phase transition. Monomer viscosities are consistent with typical literature values, although γ₁/η_splay and η_bend seem to be larger than expected for the dimer, where γ₁ is the twist viscosity. The results are discussed in terms of viscoelastic properties of semiflexible rods. The elastic properties in …

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Pressure Dependence Of The Thermal Conductivity Of Pyrophyllite To 40 Kbar, Wei Chen, Daniel L. Decker

Faculty Publications

A mathematical model for calculating the temperature distribution as a function of power delivered to a line source and the thermal conductivity of the surrounding medium in the pressure cell of a cubic-anvil press was derived. The model will handle anisotropic thermal conductivities. A simple sample assembly consisting of a line source and two or three thermocouple junctions is described. A comparison of measured to calculated temperatures yields the thermal conductivity. Thermal conductivity measurements were made on natural pyrophyllite and baked pyrophyllite to 40 kbar. For the natural pyrophyllite the thermal conductivity parallel to the bedding plane at room temperature …

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Sbi Intervention: An Old Problem- A New Perspective, William T. Jackson, George S. Vozikis, Emin Babakus

Faculty Publications

This research effort attempted to determine if SB/ intervention would change the perception of business problems by not only the business owner but also the student consultants. This focus further to encompassed firms that could be classified in either Stage I or Stage II of development. Even though there were no changes in perception by student consultants, and mixed results of whether stage development affected perceptual differences, strong support was given to the proposition that owners, overall, did change their perception of existing problems after SBI intervention.

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Slip Length In A Dilute Gas, Alejandro Garcia, D. Morris, L. Hannon

Faculty Publications

We study the phenomenon of slip length using molecular dynamics and direct simulation Monte Carlo simulations of a dilute gas. Our work extends the range of Knudsen numbers that have been previously studied. In a recent paper, Bhattacharya and Lie [Phys. Rev. 43, 761 (1991)] suggest a logarithmic dependence of slip length on Knudsen number. By a simple redefinition of the mean free path, we obtain good agreement between simulation results and Maxwell theory for slip length. The anomalies seen by Bhattacharya and Lie appear to be due to their definition of the mean free path.

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Stable Isotope Analysis Using Tunable Diode Laser Spectroscopy, Todd B. Sauke, J. F. Becker, M. Loewenstein

Faculty Publications

Measurements of ratios of stable isotopes are used in such diverse fields as petroleum prospecting, medical diagnostics, and planetary exploration. The narrow emission linewidth available from tunable diode lasers permits high-resolution infrared absorption measurements of closely spaced isotopic rovibrational lines. Our dual beam spectrometer uses the sweep integration technique in a spectral region where adjacent spectral lines are of approximately equal absorbance at the expected isotopic abundances. The experimental results reported here indicate that isotopic ratios of carbon in carbon dioxide can be measured to an accuracy of better than 0.4%. This laser spectroscopic spectrometric technique offers an alternative to …

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Solid-State Nmr Characterization Of Organics In Cement, Michael A. Janusa

Faculty Publications

Solid-state magic angle spinning nuclear magnetic resonance (MAS NMR) has been applied to cement samples containing water-soluble organics, ethylene glycol, phenol, pbromophenol and p-chlorophenol. Cement matrix development has been followed by ²⁹Si and²⁷Al NMR, which shows the organics, particularly ethylene glycol, to be promoters of silicate polymerization despite the fact that they reduce the compressive strength of the pastes. ¹³C NMR shows that phenol is completely ionized in cement pastes, but with substituted phenols in the presence of extra added metal salts, ionization is not always complete. ²H NMR on d_{5 …}

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Site Factors Affecting Growth Of Loblolly Pine In The Post Oak Belt, W. D. Hacker, M. Victor Bilan

Faculty Publications

A study was conducted in the Post Oak Belt of East Texas to determine which site factors affected height growth of loblolly pine (Pinus taeda L.). Height/age pairs were developed from stem analysis. Nonlinear regression was implemented to develop generalized height-age model. After curves were developed, stepwise regression was used to determine if an environmental variable impacted height growth. Environmental factors correlated with height growth included A horizon depth and those related to moisture relations including seasonal precipitation, average daily temperature, and texture of the A horizon. South.J. Appl. For. 16(4):197-200

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Dental And Bite Mark Evidence, Paul C. Giannelli

Faculty Publications

No abstract provided.

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Stress Begins In Kindergarten: A Look At Behavior During Standardized Testing, Pamela O. Fleege, Rosalind Charlesworth, Diane C. Burts, Craig H. Hart

Faculty Publications

Kindergarten children’s behavior before, during, and after standardized achievement testing was explored through a qualitative study in two classrooms (n = 36). Simultaneously quantitative data were collected in one of the classrooms (n = 21) before and during the testing. Data were collected through observations in the classrooms, interviews with children and teachers, and audio and video taping of the children. For the quantitative component of the study, frequencies of stress behaviors were observed using a scan sampling method. Qualitative findings indicated an increase in behaviors reported to be stress related during the testing and a decrease in those behaviors …

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Continuity Of Affine Transformations Of White Noise Test Functionals And Applications, H. H. Kuo, J. Potthoff, J. A. Yan

Faculty Publications

Translations and scalings defined on the Schwartz space of tempered distributions induce continuous transformations on the space of white noise test functionals [25]. Continuity of the induced transformations with respect to their parameters is proved. As a consequence one obtains a direct simple proof of the fact that the space of white noise test functionals is infinitely differentiable in Fréchet sense. Moreover, it is shown that the Wiener semigroup acts as a mollifier on the space of test functionals. © 1992.

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One-Dimensional Nash Groups, James J. Madden, Charles M. Stanton

Faculty Publications

A Lie group equipped with a compatible real algebraic structure is called a locally Nash group. We prove some general facts about locally Nash groups, then we classify the one-dimensional locally Nash groups, using a theorem of Weierstrass that characterizes the analytic functions satisfying an algebraic addition theorem. Besides the standard Nash structure on the additive group of real numbers, there are locally Nash structures on the additive reals induced by the exponential function, the sine function, and by any elliptic function that is real on ℝ. There are no other simply connected one-dimensional locally Nash groups. Any two quotients …

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Extensions Of Tutte's Wheels-And-Whirls Theorem, Collette R. Coullard, James G. Oxley

Faculty Publications

Tutte's wheels-and-whirls theorem states that if M is a 3-connected matroid and, for every element e, both the deletion and the contraction of e destroy 3-connectivity, then M is a wheel or a whirl. We prove some extensions of this theorem, one of which states that if M is 3-connected and has both a wheel and a whirl minor, then either M has only seven elements or there is some element the deletion or contraction of which maintains 3-connectivity and leaves a matroid with both a wheel and a whirl minor. © 1992.

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The Separation Of Zeros For Functions With Compact Spectrum, Ricardo Estrada

Faculty Publications

No abstract provided.

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The Asymptotic Expansion Of Certain Multi-Dimensional Generalized Functions, R. Estrada, R. P. Kanwal

Faculty Publications

We apply regularization of divergent integrals in the derivation of the asymptotic expansion of certain multi-dimensional generalized functions. We further present several illustrations to demonstrate that the asymptotic development of generalized functions provides a lucid formulation of many concepts in asymptotic analysis such as the expansion of oscillatory integrals and the expansion of certain series. © 1992.

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Emergence Of Radiation From Gravitational Potential Wells: The Absence Of Ωm Effects, Richard H. Price, Jorge Pullin

Faculty Publications

We consider a source of gravitational waves of frequency ω, located near the center of a massive galaxy of mass M and radius R with ωR-1. The case of odd-parity gravitational waves propagating through a perfect-fluid galaxy is particularly simple; for this case we find that, in addition to the expected redshift of the radiation emerging from the galaxy, there is a small amount of backscatter, of order Mω2R3. We show that there is no suppression of radiative power by the factor 1+ω2M24 as has been recently predicted by Kundu. The origin of Kundu's suppression lies in the interpretation of …

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Thermal Mathematical Modeling Of A Multicell Common Pressure Vessel Nickel-Hydrogen Battery, Junbom Kim, T. V. Nguyen, Ralph E. White

Faculty Publications

Atwo-dimensional and time-dependent thermal model of a multicell common pressurevessel (CPV) nickel-hydrogen battery was developed. A finite element solver calledPDE/Protran was used to solve this model. The model wasused to investigate the effects of various design parameters on thetemperature profile within the cell. The results were used tohelp find a design that will yield an acceptable temperature gradientinside a multicell CPV nickel-hydrogen battery. Steady-state and unsteady-state cases witha constant heat generation rate and a time-dependent heat generationrate were solved.

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Comparison Of Heat-Fin Materials And Design Of A Common-Pressure-Vessel Nickel-Hydrogen Battery, Junbom Kim, Ralph E. White

Faculty Publications

Atwo-dimensional, axisymmetric, and time-dependent thermal model was developed to studythe temperature behavior of the cylindrically shaped common-pressure-vessel nickel-hydrogen cell. Adifferential-energy-balance equation was used as the governing equation. A finite-element softwarepackage called PDE/Protran was used to solve this model. Different materialssuch as copper, copper beryllium, silver, and sterling silver werecompared as heat-fin materials. The heat-fin geometry (thickness and height) andspacing were tested to find a design that yielded anacceptable temperature gradient inside a nickel-hydrogen cell. Pulse heat-generation rates weretested and correlated with the time-dependent heat-generation cases.

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Mathematical Modeling Of A Primary Zinc/Air Battery, Z. Mao, Ralph E. White

Faculty Publications

Themathematical model developed by Sunu and Bennion has been extendedto include the separator, precipitation of both solid ZnO and K₂Zn(OH)₄,and the air electrode, and has been used to investigatethe behavior of a primary Zn-Air battery with respect to batterydesign features. Predictions obtained from the model indicate that anodematerial utilizationis predominantly limited by depletion of the concentration ofhydroxide ions. The effect of electrode thickness on anode material utilizationis insignificant, whereas material loading per unit volume has agreat effect on anode material utilization; a higher loading lowers boththe …

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Full-Text Articles in Entire DC Network

Tutte Polynomials Computable In Polynomial Time, J. G. Oxley, D. J.A. Welsh

Faculty Publications

Labeling Graphs With A Condition At Distance 2, Jerrold R. Griggs, Roger K. Yeh

Faculty Publications

Linear Theory Of Non-Neutral Plasma Equilibrium In A Tilted Magnetic Field, Ross L. Spencer, Grant W. Hart

Faculty Publications

Use Of Raman Spectroscopy In Characterizing Soft X-Ray Multilayers: Tools In Understanding Structure And Interfaces, Ming Cai, Qi Wang, David D. Allred, Larry V. Knight, Dorian M. Hatch, A. Reyes-Mena, Guizhong Zhang

Faculty Publications

Adaptive Boundary Detection Using “Live-Wire” Two-Dimensional Dynamic Programming, William A. Barrett, Bryan S. Morse, Eric N. Mortensen, Jayaram Udupa

Faculty Publications

Drying Of Beulah-Zap Lignite, Karl S. Vorres, David L. Wertz, Vivak Malhotra, Yuhong Dang, J.T. Joseph, Ronald Fisher

Faculty Publications

Examining An Assumption Of Linkage Between Lesson Planning And Implementation, Trena Wilkerson, Anthony J. Scheffler

Faculty Publications

Approximation By Interval Bezier Curves, Thomas W. Sederberg, Rida T. Farouki

Faculty Publications

Species Of The Cretaceous Tree Fern Tempskya From Utah, William D. Tidwell, Naomi Hebbert

Faculty Publications

Connectivity Of Submodular Functions, James Oxley, Geoff Whittle

Faculty Publications

Recoil Effects And Cp Violation In Neutron Scattering, Vladimir Gudkov

Faculty Publications

Interface Cavitation Damage In Polycrystalline Copper, Brent L. Adams, David P. Field

Faculty Publications

Viscoelastic Properties Of A Liquid-Crystalline Monomer And Its Dimer, Gregory A. Dilisi, Charles Rosenblatt, Anselm C. Griffin, Uma Hari

Faculty Publications

Pressure Dependence Of The Thermal Conductivity Of Pyrophyllite To 40 Kbar, Wei Chen, Daniel L. Decker

Faculty Publications

Sbi Intervention: An Old Problem- A New Perspective, William T. Jackson, George S. Vozikis, Emin Babakus

Faculty Publications

Slip Length In A Dilute Gas, Alejandro Garcia, D. Morris, L. Hannon

Faculty Publications

Stable Isotope Analysis Using Tunable Diode Laser Spectroscopy, Todd B. Sauke, J. F. Becker, M. Loewenstein

Faculty Publications

Solid-State Nmr Characterization Of Organics In Cement, Michael A. Janusa

Faculty Publications

Site Factors Affecting Growth Of Loblolly Pine In The Post Oak Belt, W. D. Hacker, M. Victor Bilan

Faculty Publications

Dental And Bite Mark Evidence, Paul C. Giannelli

Faculty Publications

Stress Begins In Kindergarten: A Look At Behavior During Standardized Testing, Pamela O. Fleege, Rosalind Charlesworth, Diane C. Burts, Craig H. Hart

Faculty Publications

Continuity Of Affine Transformations Of White Noise Test Functionals And Applications, H. H. Kuo, J. Potthoff, J. A. Yan

Faculty Publications

One-Dimensional Nash Groups, James J. Madden, Charles M. Stanton

Faculty Publications

Extensions Of Tutte's Wheels-And-Whirls Theorem, Collette R. Coullard, James G. Oxley

Faculty Publications

The Separation Of Zeros For Functions With Compact Spectrum, Ricardo Estrada

Faculty Publications

The Asymptotic Expansion Of Certain Multi-Dimensional Generalized Functions, R. Estrada, R. P. Kanwal

Faculty Publications

Emergence Of Radiation From Gravitational Potential Wells: The Absence Of Ωm Effects, Richard H. Price, Jorge Pullin

Faculty Publications

Thermal Mathematical Modeling Of A Multicell Common Pressure Vessel Nickel-Hydrogen Battery, Junbom Kim, T. V. Nguyen, Ralph E. White

Faculty Publications

Comparison Of Heat-Fin Materials And Design Of A Common-Pressure-Vessel Nickel-Hydrogen Battery, Junbom Kim, Ralph E. White

Faculty Publications

Mathematical Modeling Of A Primary Zinc/Air Battery, Z. Mao, Ralph E. White

Faculty Publications