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Fuel Loading Prediction Models Developed From Aerial Photographs Of The Sangre De Cristo And Jemez Mountains Of New Mexico, Usa, Kelly Scott, Brian P. Oswald, Kenneth W. Farrish, Daniel Unger Jan 2002

Fuel Loading Prediction Models Developed From Aerial Photographs Of The Sangre De Cristo And Jemez Mountains Of New Mexico, Usa, Kelly Scott, Brian P. Oswald, Kenneth W. Farrish, Daniel Unger

Faculty Publications

Fuel load prediction equations that made use of aerial photographs were developed for Mixed Conifer, Ponderosa Pine (Pinus ponderosa Dougl. ex Laws.) and Pinyon-Juniper (Pinus edulis Engelm.)-(Juniperusmonosperma Engelm.) cover types from one-time measurements made in the Santa Fe watershed (SFWS) located in the Sangre de Cristo Mountains of northern New Mexico, and at Los Alamos National Laboratory (LANL) located in the Jemez Mountains of northern New Mexico. The results of the watershed data set were favorable and exhibited a high degree of relative accuracy. The results from the LANL data set did not share the same degree of accuracy, …

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The Planetary Nebula Spectrograph: The Green Light For Galaxy Kinematics, N. G. Douglas, M. Arnaboldi, K. C. Freeman, K. Kuijken, M. R. Merrifield, Aaron J. Romanowsky, K. Taylor, M. Capaccioli, T. Axelrod, R. Gilmozzi, J. Hart, G. Bloxham, D. Jones Jan 2002

The Planetary Nebula Spectrograph: The Green Light For Galaxy Kinematics, N. G. Douglas, M. Arnaboldi, K. C. Freeman, K. Kuijken, M. R. Merrifield, Aaron J. Romanowsky, K. Taylor, M. Capaccioli, T. Axelrod, R. Gilmozzi, J. Hart, G. Bloxham, D. Jones

Faculty Publications

Planetary nebulae (PNe) are now well established as probes of galaxy dynamics and as standard candles in distance determinations. Motivated by the need to improve the efficiency of planetary nebulae searches and the speed with which their radial velocities are determined, a dedicated instrument—the Planetary Nebula Spectrograph, or PN.S—has been designed and commissioned at the 4.2 m William Herschel Telescope. The high optical efficiency of the spectrograph results in the detection of typically ∼150 PNe in galaxies at the distance of the Virgo Cluster in one night of observations. In the same observation, the radial velocities are obtained with an …

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Sobre Universos Y Teologías: Schleiermacher Y La Cuestión Cosmológica, Guillermo C. Hansen Jan 2002

Sobre Universos Y Teologías: Schleiermacher Y La Cuestión Cosmológica, Guillermo C. Hansen

Faculty Publications

No abstract provided.

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Decomposition Of Pascal’S Kernels Mod PS, Richard P. Kubelka Jan 2002

Decomposition Of Pascal’S Kernels Mod PS, Richard P. Kubelka

Faculty Publications

For a prime p we define Pascal's Kernel K(p,s) = [k(p,s)ij]∞i,j=0 as the infinite matrix satisfying k(p,s)ij = 1/px(i+jj) mod p if (i+jj) is divisible by ps and k(p,s)ij = 0 otherwise. While the individual entries of Pascal's Kernel can be computed using a formula of Kazandzidis that has been known for some time, our purpose here will be to use that formula …

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Comment On ‘‘Stress-Density Ratio Slip-Corrected Reynolds Equation For Ultra-Thin Film Gas Bearing Lubrication’’, Alejandro Garcia Jan 2002

Comment On ‘‘Stress-Density Ratio Slip-Corrected Reynolds Equation For Ultra-Thin Film Gas Bearing Lubrication’’, Alejandro Garcia

Faculty Publications

No abstract provided.

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Divine Foreknowledge And The Arrow Of Time: On The Impossibility Of Retrocausation, Alan G. Padgett Jan 2002

Divine Foreknowledge And The Arrow Of Time: On The Impossibility Of Retrocausation, Alan G. Padgett

Faculty Publications

No abstract provided.

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Theology As Worship: The Place Of Theology In A Postmodern University, Alan G. Padgett Jan 2002

Theology As Worship: The Place Of Theology In A Postmodern University, Alan G. Padgett

Faculty Publications

No abstract provided.

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Recent Applications Of Flame Atomic Absorption Spectrometry To Environmental Measurements, Michael A. Janusa Jan 2002

Recent Applications Of Flame Atomic Absorption Spectrometry To Environmental Measurements, Michael A. Janusa

Faculty Publications

Atomic absorption spectroscopy is very useful for the determination of a large number of elements, especially at trace levels. It is a widely used technique for analysis of a wide variety of sample matrices including biota, soils, and water. Atomic absorption spectroscopy is a very reputable technique that is inexpensive and delivers accurate results even in a complex matrix. This review focuses on the applications of flame atomic absorption spectroscopy to environmental measurements, and is mainly based on papers published from 1999–2002.

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Soil Leachate Responses During 10 Years Of Induced Whole-Watershed Acidification, Pamela J. Edwards, James N. Kochenderfer, Dean W. Coble, Mary Beth Adams Jan 2002

Soil Leachate Responses During 10 Years Of Induced Whole-Watershed Acidification, Pamela J. Edwards, James N. Kochenderfer, Dean W. Coble, Mary Beth Adams

Faculty Publications

Soil solution was collected from zero-tension lysimeters for 10 yr on two small central Appalachian watersheds in West Virginia, U.S.A. Ammonium sulfate fertilizer was applied to one catchment 3 times per year during each year. The other watershed was used as a reference to account for ambient baseline conditions. Ca and Mg concentrations collected below the A- and B-horizons of the treated watershed increased and then decreased over time as a result of the treatment. By contrast, Ca and Mg concentrations in the C-horizon continued to increase throughout the study period.

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Financial Maturity Concepts With Application To Three Hardwood Timber Stands, Steven H. Bullard, D. L. Grebner, K. L. Belli Jan 2002

Financial Maturity Concepts With Application To Three Hardwood Timber Stands, Steven H. Bullard, D. L. Grebner, K. L. Belli

Faculty Publications

Timber is “financially mature” when its rate of value increase falls below what the landowner can earn in alternative investments that are comparable in duration, risk, liquidity, and other factors. The basic concept of financial maturity is simple, but in application it involves several very important, basic questions and issues.

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Effect Of Ga Content On Defect States In Cuin1-XGaXSe2 Photovoltaic Devices, Jennifer T. Heath, J. David Cohen, William N. Shafarman, Dongxiang Liao, Angus Rockett Jan 2002

Effect Of Ga Content On Defect States In Cuin1-XGaXSe2 Photovoltaic Devices, Jennifer T. Heath, J. David Cohen, William N. Shafarman, Dongxiang Liao, Angus Rockett

Faculty Publications

Defects in the band gap of CuIn1-xGaxSe2 have been characterized using transient photocapacitance spectroscopy. The measured spectra clearly show response from a band of defects centered around 0.8 eV from the valence band edge as well as an exponential distribution of band tail states. Despite Ga contents ranging from Ga/(In+Ga)=0.0 to 0.8, the defect bandwidth and its position relative to the valence band remain constant. This defect band may act as an important recombination center, contributing to the decrease in device efficiency with increasing Ga content.

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The Emerging Role Of Ethics Advisors, General Counsel, And Other Compliance Specialists In Large Law Firms, Elizabeth Chambliss, David B. Wilkins Jan 2002

The Emerging Role Of Ethics Advisors, General Counsel, And Other Compliance Specialists In Large Law Firms, Elizabeth Chambliss, David B. Wilkins

Faculty Publications

No abstract provided.

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The Polar Expression Of Enso And Sea-Ice Variability As Recorded In A South Pole Ice Core, Eric A. Meyerson, Paul A. Mayewski, Karl J. Kreutz, L. David Meeker, Sallie I. Whitlow, Mark S. Twickler Jan 2002

The Polar Expression Of Enso And Sea-Ice Variability As Recorded In A South Pole Ice Core, Eric A. Meyerson, Paul A. Mayewski, Karl J. Kreutz, L. David Meeker, Sallie I. Whitlow, Mark S. Twickler

Faculty Publications

An annually dated ice core recovered from South Pole (2850 m a.s.l.) in 1995, that covers the period 1487–1992, was analyzed for the marine biogenic sulfur species methanesulfonate (MS). Empirical orthogonal function analysis is used to calibrate the high-resolution MS series with associated environmental series for the period of overlap (1973–92). Utilizing this calibration we present a ~500 year long proxy record of the polar expression of the El Niño–Southern Oscillation (ENSO) and southeastern Pacific sea-ice extent variations. These records reveal short-term periods of increased (1800–50, 1900–40) and decreased sea-ice extent (1550–1610, 1660–1710, 1760–1800). In general, increased (decreased) sea-ice extent …

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Single-Photon Quantum-Nondemolition Detectors Constructed With Linear Optics And Projective Measurements, Pieter Kok, Hwang Lee, Jonathan P. Dowling Jan 2002

Single-Photon Quantum-Nondemolition Detectors Constructed With Linear Optics And Projective Measurements, Pieter Kok, Hwang Lee, Jonathan P. Dowling

Faculty Publications

Optical quantum-nondemolition devices can provide essential tools for quantum information processing. Here, we describe several optical interferometers that signal the presence of a single photon in a particular input state without destroying it. We discuss both entanglement-assisted and nonentanglement-assisted interferometers, with ideal and realistic detectors. We found that the existing detectors with 88% quantum efficiency and single-photon resolution can yield output fidelities of up to 89%, depending on the input state. Furthermore, we construct expanded protocols to perform quantum-nondemolition detections of single photons that leave the polarization invariant. For detectors with 88% efficiency, we found polarization-preserving output fidelities of up …

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The Effect Of Reactor Geometry On Frontal Polymerization Spin Modes, John A. Pojman, Jonathan Masere, Enrico Petretto, Mauro Rustici, Do Sung Huh, Min Suk Kim, Vladimir Volpert Jan 2002

The Effect Of Reactor Geometry On Frontal Polymerization Spin Modes, John A. Pojman, Jonathan Masere, Enrico Petretto, Mauro Rustici, Do Sung Huh, Min Suk Kim, Vladimir Volpert

Faculty Publications

Using reactors of different sizes and geometries the dynamics of the frontal polymerization of 1,6-hexanediol diacrylate (HDDA) and pentaerythritol tetraacrylate (PETAC), with ammonium persulfate as the initiator were studied. For this system, the frontal polymerization exhibits complex behavior that depends on the ratio of the monomers. For a particular range of monomers concentration, the polymerization front becomes nonplanar, and spin modes appear. By varying the reactor diameter, we experimentally confirmed the expected shift of the system to a greater number of "hot spots" for larger diameters. For square test tubes a "zig-zag" mode was observed for the first time in …

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Packing Cycles In Graphs, Guoli Ding, Wenan Zang Jan 2002

Packing Cycles In Graphs, Guoli Ding, Wenan Zang

Faculty Publications

A graph G is called cycle Mengerian (CM) if for all nonnegative integral function w defined on V(G), the maximum number of cycles (repetition is allowed) in G such that each vertex v is used at most w(v) times is equal to the minimum of ∑ {w(x) : x ∈ X}, where the minimum is taken over all X ⊆ V(G) such that deleting X from G results in a forest. The purpose of this paper is to characterize all CM graphs in terms of forbidden structures. As a corollary, we prove that if the fractional version of the above …

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Compactification Of Classical Groups, Hongyu He Jan 2002

Compactification Of Classical Groups, Hongyu He

Faculty Publications

No abstract provided.

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Chapter 23 Optimal Design Of Gradient Fields With Applications To Electrostatics, Robert Lipton, Ani P. Velo Jan 2002

Chapter 23 Optimal Design Of Gradient Fields With Applications To Electrostatics, Robert Lipton, Ani P. Velo

Faculty Publications

No abstract provided.

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On Matroids Of Branch-Width Three, Rhiannon Hall, James Oxley, Charles Semple, Geoff Whittle Jan 2002

On Matroids Of Branch-Width Three, Rhiannon Hall, James Oxley, Charles Semple, Geoff Whittle

Faculty Publications

For all positive integers k, the class Bk of matroids of branch-width at most k is minor-closed. When k is 1 or 2, the class Bk is, respectively, the class of direct sums of loops and coloops, and the class of direct sums of series-parallel networks. B3 is a much richer class as it contains infinite antichains of matroids and is thus not well-quasi-ordered under the minor order. In this paper, it is shown that, like B1 and B2, the class B3 can be characterized by a finite list of excluded minors. © 2002 Elsevier Science (USA).

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Totally Free Expansions Of Matroids, James Geelen, James Oxley, Dirk Vertigan, Geoff Whittle Jan 2002

Totally Free Expansions Of Matroids, James Geelen, James Oxley, Dirk Vertigan, Geoff Whittle

Faculty Publications

The aim of this paper is to give insight into the behaviour of inequivalent representations of 3-connected matroids. An element x of a matroid M is fixed if there is no extension M′ of M by an element x′ such that {x, x′} is independent and M′ is unaltered by swapping the labels on x and x′. When x is fixed, a representation of M.\x extends in at most one way to a representation of M. A 3-connected matroid N is totally free if neither N nor its dual has a fixed element whose deletion is a series extension of …

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Mixed-Mode Shell-Model Theory For Nuclear Structure Studies, V. G. Gueorguiev, W. E. Ormand, C. W. Johnson, J. P. Draayer Jan 2002

Mixed-Mode Shell-Model Theory For Nuclear Structure Studies, V. G. Gueorguiev, W. E. Ormand, C. W. Johnson, J. P. Draayer

Faculty Publications

We introduce a shell-model theory that combines traditional spherical states, which yield a diagonal representation of the usual single-particle interaction, with collective configurations that track deformations, and test the validity of this mixed-mode, oblique-basis shell-model scheme on [Formula Presented] The correct binding energy (within 2% of the full-space result) as well as low-energy configurations that have greater than 90% overlap with full-space results are obtained in a space that spans less than 10% of the full space. The results suggest that a mixed-mode shell-model theory may be useful in situations where competing degrees of freedom dominate the dynamics and full-space …

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Hyperbolicity Of The Baumgarte-Shapiro-Shibata-Nakamura System Of Einstein Evolution Equations, Olivier Sarbach, Gioel Calabrese, Jorge Pullin, Manuel Tiglio Jan 2002

Hyperbolicity Of The Baumgarte-Shapiro-Shibata-Nakamura System Of Einstein Evolution Equations, Olivier Sarbach, Gioel Calabrese, Jorge Pullin, Manuel Tiglio

Faculty Publications

We discuss an equivalence between the Baumgarte-Shapiro-Shibata-Nakamura (BSSN) formulation of the Einstein evolution equations, a subfamily of the Kidder-Scheel-Teukolsky formulation, and other strongly or symmetric hyperbolic first order systems with fixed shift and densitized lapse. This allows us to show under which conditions the BSSN system is, in a sense to be discussed, hyperbolic. This desirable property may account in part for the empirically observed better behavior of the BSSN formulation in numerical evolutions involving black holes. © 2002 The American Physical Society.

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Finite Spin-Foam-Based Theory Of Three- And Four-Dimensional Quantum Gravity, Rodolfo Gambini, Jorge Pullin Jan 2002

Finite Spin-Foam-Based Theory Of Three- And Four-Dimensional Quantum Gravity, Rodolfo Gambini, Jorge Pullin

Faculty Publications

Starting from Ooguri's construction for BF theory in three (and four) dimensions, we show how to construct a well defined theory with an infinite number of degrees of freedom. The spin network states that are kept invariant by the evolution operators of the theory are exact solutions of the Hamiltonian constraint of quantum gravity proposed by Thiemann. The resulting theory is the first example of a well defined, finite, consistent, spin-foam-based theory in a situation with an infinite number of degrees of freedom. Since it solves the quantum constraints of general relativity it is also a candidate for a theory …

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Close Limit Evolution Of Kerr-Schild Type Initial Data For Binary Black Holes, Olivier Sarbach, Manuel Tiglio, Jorge Pullin Jan 2002

Close Limit Evolution Of Kerr-Schild Type Initial Data For Binary Black Holes, Olivier Sarbach, Manuel Tiglio, Jorge Pullin

Faculty Publications

We eyolve the binary black hole initial data family proposed by Bishop et al. in the limit in which the black holes are close to each other. We present an exact solution of the linearized initial value problem based on their proposal and make use of a recently introduced generalized formalism for studying perturbations of Schwarzschild black holes in arbitrary coordinates to perform the evolution. We clarify the meaning of the free parameters of the initial data family through the results for the radiated energy and waveforms from the black hole collision. © 2002 The American Physical Society.

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Semiparametric Maximum Likelihood Estimates Of Spatial Dependence, R. Kelley Pace, James P. Lesage Jan 2002

Semiparametric Maximum Likelihood Estimates Of Spatial Dependence, R. Kelley Pace, James P. Lesage

Faculty Publications

We semiparametrically model spatial dependence via a combination of simpler weight matrices (termed spatial basis matrices) and fit this model via maximum likelihood. Estimation of the model relies on the intuition that bounds to the log-determinant term in the log-likelihood can provide penalties to overfitting both the level and pattern of spatial dependence. By relying on symmetric and doubly stochastic spatial basis matrices that reflect different weight specifications assigned to neighboring observations, we are able to derive a mathematical expression for bounds on the log-determinant term that appears in the likelihood function. These bounds can be conveniently calculated allowing us …

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Crustal Fissuring On The Crest Of The Southern East Pacific Rise At 17˚15'-40'S, Dawn J. Wright, Rachel M. Haymon, Scott M. White, Ken C. Macdonald Jan 2002

Crustal Fissuring On The Crest Of The Southern East Pacific Rise At 17˚15'-40'S, Dawn J. Wright, Rachel M. Haymon, Scott M. White, Ken C. Macdonald

Faculty Publications

Fissure densities and widths have been mapped along the axial zone of the superfast spreading southern East Pacific Rise (EPR) at 17_150–400S with the near-bottom DSL-120 and Argo II imaging systems. We observe that the youngest lava flows (on a relative age scale) are sparsely fissured and that there is a cumulative increase in fissure abundance with time that produces a strong positive correlation between fissure density and relative age of lava flows. Average fissure widths were used to estimate fissure depths. In the 17_150–400S area, calculated fissure depths are estimated to extend below the seismic layer 2A/2B boundary, and …

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The Form And Substance Of Environmental Justice: The Challenge Of Title Vi Of The Civil Rights Act Of 1964 For Environmental Regulation, Tseming Yang Jan 2002

The Form And Substance Of Environmental Justice: The Challenge Of Title Vi Of The Civil Rights Act Of 1964 For Environmental Regulation, Tseming Yang

Faculty Publications

No abstract provided.

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Melding Civil Rights And Environmentalism: Finding Environmental Justice's Place In Environmental Regulation, Tseming Yang Jan 2002

Melding Civil Rights And Environmentalism: Finding Environmental Justice's Place In Environmental Regulation, Tseming Yang

Faculty Publications

No abstract provided.

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Water Transport In Polymer Electrolyte Membrane Electrolyzers Used To Recycle Anhydrous Hcl: I. Characterization Of Diffusion And Electro-Osmotic Drag, Sathya Motupally, Aaron J. Becker, John W. Weidner Jan 2002

Water Transport In Polymer Electrolyte Membrane Electrolyzers Used To Recycle Anhydrous Hcl: I. Characterization Of Diffusion And Electro-Osmotic Drag, Sathya Motupally, Aaron J. Becker, John W. Weidner

Faculty Publications

In this paper, diffusion and electro-osmotic drag of water across Nafion® membranes in the presence of HCl are characterized. For all the measurements, one side of the Nafion membrane was in contact with liquid water and the other side with gaseous anhydrous HCl. To characterize diffusion of water, the open-circuit flux of water across a catalyst-coated Nafion 115 membrane was measured as a function of HCl flow rate and temperature at a constant cell pressure of 1 atm. Due to the nature of varying driving force for diffusion as a function of HCl flow rate, the experimental data was analyzed …

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Modeling The Effects Of Ion Association On Alternating Current Impedance Of Solid Polymer Electrolytes, Changqing Lin, Ralph E. White, Harry J. Ploehn Jan 2002

Modeling The Effects Of Ion Association On Alternating Current Impedance Of Solid Polymer Electrolytes, Changqing Lin, Ralph E. White, Harry J. Ploehn

Faculty Publications

This work presents a rigorous continuum model describing the transport of ions and associated ion pairs in solid polymer electrolytes subjected to small amplitude alternating current (ac) excitation. The model treats ion association as a reversible reaction among ions and ion pairs. Dimensionless governing equations are developed from component mass balances, flux equations based on dilute solution theory, and the Poisson equation. Assuming reversible electrode reactions and electroneutrality, the model equations have an analytical solution. Further simplifications are possible in limiting cases (weak and strong association, zero and infinite frequency excitation), giving expressions consistent with previously published models. We use …

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