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Mathematical Modeling Of A Nickel-Cadmium Battery: Effects Of Intercalation And Oxygen Reactions, Deyuan Fan, Ralph E. White Jan 1991

Mathematical Modeling Of A Nickel-Cadmium Battery: Effects Of Intercalation And Oxygen Reactions, Deyuan Fan, Ralph E. White

Faculty Publications

Extensions are presented for a previously published (1) mathematical model of a nickel-cadmium (Ni-Cd) cell. These extensions consist of intercalation thermodynamics for the nickel electrode and oxygen generation and reduction reactions during charge and overcharge. The simulated results indicate that intercalation may be important in the nickel electrode and that including the oxygen reactions provides a means of predicting the efficiency of the cell on charge and discharge.

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Effect Of Ohmic, Mass-Transfer, And Kinetic Resistances On Linear-Sweep Voltammetry In A Cylindrical-Pore Electrode, John W. Weidner, Peter S. Fedkiw Jan 1991

Effect Of Ohmic, Mass-Transfer, And Kinetic Resistances On Linear-Sweep Voltammetry In A Cylindrical-Pore Electrode, John W. Weidner, Peter S. Fedkiw

Faculty Publications

Extracting quantitative kinetic information from linear-sweep voltammograms (LSV) on porous electrodes is more difficult than on planar electrodes since the electrode surface is not uniformly accessible to the bulk supply of reactant or the counterelectrode. We present here a means to account for the effect of ohmic, mass-transfer, and kinetic resistances on LSV by modeling a pore in a porous matrix as a cylindrical-pore electrode, and solving the mass and charge conservation equations in the context of this geometry for the simply redox reaction O + ne– <=> R where both O and R are soluble species. Both analytical …

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Reducing The Recovery Of Avoidable Seat-Belt Damages: A Cure For The Defects Of Waterson V. General Motors Corporation, Paul A. Lebel Jan 1991

Reducing The Recovery Of Avoidable Seat-Belt Damages: A Cure For The Defects Of Waterson V. General Motors Corporation, Paul A. Lebel

Faculty Publications

No abstract provided.

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The Rhetoric Of Equality, Neal Devins Jan 1991

The Rhetoric Of Equality, Neal Devins

Faculty Publications

No abstract provided.

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Teacher Education: Student Teacher Views Vs. Those Of Cooperating Teachers, Richard Stahlhut, Lynn Williford, Richard Hawkes, Joseph Fratianni Jan 1991

Teacher Education: Student Teacher Views Vs. Those Of Cooperating Teachers, Richard Stahlhut, Lynn Williford, Richard Hawkes, Joseph Fratianni

Faculty Publications

A survey was conducted on the quality of preparation in teacher education of student teachers at the University of Northern Iowa and their performance level during student teaching. Student teachers were asked to assess teacher education program contributions to 29 competencies relevant to teaching effectiveness; plus their overall teacher effectiveness. Similarly; cooperating teachers were asked to assess the same competencies as exhibited by the student teachers they supervised. Of the 369 (78.5 percent) questionnaires returned; 192 were from student teachers and 177 were from cooperating teachers. Data analysis was based on matched pairs of responses. An overall summary of the …

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Power Law Exponents For A Spreading Front And Growing Interface In An Irreversible Wetting, Evan Willett, Ras B. Pandey Dec 1990

Power Law Exponents For A Spreading Front And Growing Interface In An Irreversible Wetting, Evan Willett, Ras B. Pandey

Faculty Publications

Using computer simulations, the power-law behavior of the interface growth of a spreading fluid is studied in a two-dimensional lattice model. The interface width exponent ν and the dynamical exponent k for the evolution of the front are consistent with their dynamical scaling relation. The magnitude of these exponents seems to depend upon the nature of the substrate and the concentration of the carriers of the wetting fluid.

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In Situ Infrared Evidence For The Electrochemical Incorporation Of Hydrogen Into Si And Ge, K. C. Mandal, F. Ozanam, J.-N. Chazalviel Dec 1990

In Situ Infrared Evidence For The Electrochemical Incorporation Of Hydrogen Into Si And Ge, K. C. Mandal, F. Ozanam, J.-N. Chazalviel

Faculty Publications

No abstract provided.

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Genevan Scholars In Intellectual Europe: From The 17th Century To The Middle Of The 19th Century - French, Theodore S. Feldman Dec 1990

Genevan Scholars In Intellectual Europe: From The 17th Century To The Middle Of The 19th Century - French, Theodore S. Feldman

Faculty Publications

No abstract provided.

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Epicomplete Archimedean L-Groups Via A Localic Yosida Theorem, James Madden, J. Vermeer Nov 1990

Epicomplete Archimedean L-Groups Via A Localic Yosida Theorem, James Madden, J. Vermeer

Faculty Publications

No abstract provided.

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Purification And Characterization Of A Dna Polymerase From The Cyanobacterium Anacystis Nidulans R2, Hsiu-Jin Lin, Gordon C. Cannon, Sabine Heinhorst Nov 1990

Purification And Characterization Of A Dna Polymerase From The Cyanobacterium Anacystis Nidulans R2, Hsiu-Jin Lin, Gordon C. Cannon, Sabine Heinhorst

Faculty Publications

A DNA polymerase has been highly purified from Anacystis nidulans R2. Electrophoretic analysis in sodium dodecyl sulfate-polyacrylamide gels revealed that the final fraction contains three bands of Mr 107,000, 93,000, and 51,000, respectively. Analysis of purified DNA polymerase activity in situ indicates that of the three polypeptides the Mr 107,000 species has the catalytic activities. The native molecular weight of the enzyme was estimated by glycerol gradient sedimentation to be 100,000. The enzyme has an absolute requirement for a divalent cation. Mg2+ can be replaced with Mn2+, but the DNA polymerase is less active. Potassium …

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Degree Of Adaptive Approximation, Ronald A. Devore, Ming Yu Xiang Oct 1990

Degree Of Adaptive Approximation, Ronald A. Devore, Ming Yu Xiang

Faculty Publications

We obtain various estimates for the error in adaptive approximation and also establish a relationship between adaptive approximation and free-knot spline approximation.

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The Secret Of Success: The Small-Section First-Year Skills Offering And Its Relationship To Independent Thinking, James E. Moliterno Oct 1990

The Secret Of Success: The Small-Section First-Year Skills Offering And Its Relationship To Independent Thinking, James E. Moliterno

Faculty Publications

No abstract provided.

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The Effect Of Externally Applied Oscillating Electric Fields On The L=1 And L=2 Diocotron Modes In Non-Neutral Plasmas, Ross L. Spencer Oct 1990

The Effect Of Externally Applied Oscillating Electric Fields On The L=1 And L=2 Diocotron Modes In Non-Neutral Plasmas, Ross L. Spencer

Faculty Publications

A high-frequency oscillating electric field can change the properties of diocotron modes in non-neutral plasmas. The effect depends crucially on the azimuthal mode number, m, of the applied field. For m=0, plus or minus 1 there is no effect, and for applied standing waves there is also no effect. But if the applied field has the form of a traveling wave with the norm of m greater than or equal to 2, the frequency of stable diocotron modes can be modified and for the norm of m greater than or equal to 3, the l=2 instability of hollow density profiles …

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Computer Simulation Study Of Conductivity In A 2-Dimensional Binary Fluid Mixture, Ras B. Pandey Sep 1990

Computer Simulation Study Of Conductivity In A 2-Dimensional Binary Fluid Mixture, Ras B. Pandey

Faculty Publications

A computer-simulation model is introduced to study the transport properties of a binary fluid mixture in which the constituents of one fluid (the tracer particles) carry charges in a linear charge-density gradient in the background charge of the second fluid. In the steady-state equilibrium, an effective conductivity σc(p,r) is estimated as a function of the carrier concentration p and the range of interactions r. The conductivity is observed to vary nonmonotonically with the concentration p, and it exhibits a maximum at a characteristic value pc. The conductivity decreases when the …

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Techniques For Cubic Algebraic Surfaces Ii, Thomas W. Sederberg Sep 1990

Techniques For Cubic Algebraic Surfaces Ii, Thomas W. Sederberg

Faculty Publications

A survey of some techniques that may have potential for free-form modeling with algebraic surfaces is continued. Classical results as well as several recent innovations are included. Specific attention is paid to cubic algebraic surfaces, although many of the ideas presented have application to algebraic surfaces of any degree. Topics addressed include piecewise constructions, interpolation to points and space curves, and parameterization.

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Theory Of Light Scattering By A Nonequilibrium Binary Mixture, J.C. Nieuwoudt, B.M. Law Aug 1990

Theory Of Light Scattering By A Nonequilibrium Binary Mixture, J.C. Nieuwoudt, B.M. Law

Faculty Publications

A binary mixture subject to a large temperature gradient is studied. Solutions of the evolution equations for the time-dependent fluctuation correlations are obtained using mode-coupling theory subject to the assumption that the mixture is not close to a critical point. From these results predictions for the light-scattering spectrum at the Rayleigh and Brillouin lines are made. The temperature gradient is shown to cause a large enhancement of the scattering amplitude at the Rayleigh line, whereas the effect at the Brillouin line is found to be small.

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Techniques For Cubic Algebraic Surfaces I, Thomas W. Sederberg Jul 1990

Techniques For Cubic Algebraic Surfaces I, Thomas W. Sederberg

Faculty Publications

The tutorial presents some tools for free-form modeling with algebraic surfaces, that is, surfaces that can be defined using an implicit polynomial equation f(x, y, z )=0. Cubic algebraic surfaces (defined by an implicit equation of degree 3) are emphasized. While much of this material applies only to cubic surfaces, some applies to algebraic surfaces of any degree. This area of the tutorial introduces terminology, presents different methods for defining and modeling with cubic surfaces, and examines the power basis representation of algebraic surfaces. Methods of forcing an algebraic surface to interpolate a set of points or a space curve …

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Universal Scaling Of Nonlocal And Local Resistance Fluctuations In Small Wires, H. Haucke, S. Washburn, A. D. Benoit, C. P. Umbach, Richard A. Webb Jun 1990

Universal Scaling Of Nonlocal And Local Resistance Fluctuations In Small Wires, H. Haucke, S. Washburn, A. D. Benoit, C. P. Umbach, Richard A. Webb

Faculty Publications

Resistance fluctuations in small metal samples result from coherent transport of the carriers. The wave functions of the carriers extend into regions which are not accessible classically. We have directly measured the length dependence of the nonlocal magnetoresistance fluctuations in Sb and Au wires by studying regions of our samples separated from the classical current path by a distance L which varied from 3Lcphi down to 0.2Lcphi (where Lcphi is the phase coherence length for the carriers in the metal). These fluctuations decay exponentially with L/Lcphi. Measurements along the classical current paths scale more slowly …

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Tomlinsonia Stichkania Sp. Nov., A Permineralized Grass From The Pliocene To (?)Pleistocene China Ranch Beds In Sperry Wash, California, William D. Tidwell, E. M. V. Nambudiri Jun 1990

Tomlinsonia Stichkania Sp. Nov., A Permineralized Grass From The Pliocene To (?)Pleistocene China Ranch Beds In Sperry Wash, California, William D. Tidwell, E. M. V. Nambudiri

Faculty Publications

Permineralized specimens of grasses assignable to Tomlinsonia as a new species Tomlinsonia stichkania occur in the China Ranch beds of Pliocene to possible Pleistocene age in Sperry Wash in the Alexander Hills of southeastern California. The round culm of these grasses is generally solid or occasionally hollow with collateral vascular bundles in the distinct outer and indistinct inner rings. Two-ranked leaf sheaths alternately encircle and overlap the culm. Ridges and furrows occur in the abaxial surfaces of the sheaths. The epidermis of the leaf sheaths is similar to that of the culm. The leaf lamina consists of a three-layered mesophyll. …

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Eigenvalue Problems Of Ginzburg–Landau Operator In Bounded Domains, Kening Lu, Xing-Bin Pan Jun 1990

Eigenvalue Problems Of Ginzburg–Landau Operator In Bounded Domains, Kening Lu, Xing-Bin Pan

Faculty Publications

In this paper we study the eigenvalue problems for the Ginzburg–Landau operator with a large parameter in bounded domains in [openface R]2 under gauge invariant boundary conditions. The estimates for the eigenvalues are obtained and the asymptotic behavior of the associated eigenfunctions is discussed. These results play a key role in estimating the critical magnetic field in the mathematical theory of superconductivity.

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On An Excluded-Minor Class Of Matroids, James G. Oxley May 1990

On An Excluded-Minor Class Of Matroids, James G. Oxley

Faculty Publications

A result of Walton and the author establishes that every 3-connected matroid of rank and corank at least three has one of five 6-element rank-3 self-dual matroids as a minor. One of these matroids is the rank-3 whirl W3. Another is the rank-3 matroid P6 that consists of a single 3-point line together with three points off the line. This paper determines the structure of the class of matroids that is obtained by excluding as minors both W3 and P6. As a consequence of this result, we deduce a characterization of the class of GF(4)-representable matroids with no W3-minor. © …

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Consistency And Generalization In Incrementally Trained Connectionist Networks, Tony R. Martinez May 1990

Consistency And Generalization In Incrementally Trained Connectionist Networks, Tony R. Martinez

Faculty Publications

This paper discusses aspects of consistency and generalization in connectionist networks which learn through incremental training by examples or rules. Differences between training set learning and incremental rule or example learning are presented. Generalization, the ability to output reasonable mappings when presented with novel input patterns, is discussed in light of the above learning methods. In particular, the contrast between humming distance generalization and generalizing by high order combinations of critical variables is overviewed. Examples of detailed rules for an incremental learning model are presented for both consistency and generalization constraints.

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Interactive Morphometrics From Three-Dimensional Surface Images, William A. Barrett, Shawn C. Becker May 1990

Interactive Morphometrics From Three-Dimensional Surface Images, William A. Barrett, Shawn C. Becker

Faculty Publications

Techniques have been developed for extracting three-dimensional (3D) measurements directly and interactively from 3D representations of surface anatomy. In order to obtain 3D measurements the anatomical surface is interrogated directly through the use of morphometric tools. Morphometric tools include points, 3D graphical "probes", and logical sectioning functions which interact with the surface through depth buffer compositing operations. Tools are interactively positioned on or through the surface to measure surface dimensions and partial volumes, or to define intersecting functions which allow surface anatomy to be visualized in the context of surrounding anatomy. Visualization is also enhanced because tools reveal much pertaining …

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Norms Of Positive Operators On Lp-Spaces, Ralph Howard, Anton R. Schep May 1990

Norms Of Positive Operators On Lp-Spaces, Ralph Howard, Anton R. Schep

Faculty Publications

No abstract provided.

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Chloroplast And Mitochondrial: Dna Polymerases From Cultured Soybean Cells, Sabine Heinhorst, Gordon C. Cannon, Arthur Weissbach Apr 1990

Chloroplast And Mitochondrial: Dna Polymerases From Cultured Soybean Cells, Sabine Heinhorst, Gordon C. Cannon, Arthur Weissbach

Faculty Publications

DNA polymerases were purified from chloroplasts and mitochondria of cultured Glycine max cells. The chloroplast enzyme exists in two forms which are indistinguishable from each other biochemically. All three organellar enzymes have an estimated molecular weight of 85,000 to 90,000 and prefer poly(rA)dT12-18 over activated DNA as a template in vitro. Maximum activity of the chloroplast and mitochondrial DNA polymerases requires KCI and a reducing agent, and the enzymes are completely resistant to inhibitors of DNA polymerase a. Taken together, these properties classify the soybean organellar enzymes as DNA polymerases y. A unique feature that distinguishes the plant enzymes from …

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A Scale Of Linear Spaces Related To The Lp Scale, S J. Dilworth Apr 1990

A Scale Of Linear Spaces Related To The Lp Scale, S J. Dilworth

Faculty Publications

No abstract provided.

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Project Clear's Paper Choice: A Hypertext System For Giving Advice About Legal Research, I. Trotter Hardy Apr 1990

Project Clear's Paper Choice: A Hypertext System For Giving Advice About Legal Research, I. Trotter Hardy

Faculty Publications

Project CLEAR-Computers in Legal Education: Assistance with Research-applies computer techniques to teaching and advising students about legal research. "Hypertext" is a software technique appropriate both for creating information structures that users can browse through, and for creating question-and-answer decision trees that provide specific advice to users. These two hypertext techniques have been put together in Project CLEAR's Paper Choice, a computer program that provides knowledge and gives advice to law students about legal research.

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Leadership In The Library/Lnformation Profession, Robert V. Williams Apr 1990

Leadership In The Library/Lnformation Profession, Robert V. Williams

Faculty Publications

https://www.sla.org/content/shop/speclibs.cfm ©1990 Special Libraries Association

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Central And South America Gps Geodesy- Casa Uno, James N. Kellogg, Timothy H. Dixon Mar 1990

Central And South America Gps Geodesy- Casa Uno, James N. Kellogg, Timothy H. Dixon

Faculty Publications

In January 1988, scientists from over 25 organizations in 13 countries and territories cooperated in the largest Global Positioning System (GPS) campaign in the world to date (Table 1). 43 GPS receivers collected approximately 590 station-days of data in America, Samoa, Australia, Canada, Colombia, Costa Rica, Ecuador, New Zealand, Norway, Panama, Sweden, United States, West Germany, and Venezuela. The experiment was entitled CASA UNO, an acronym for Central and South America -- and uno is the Spanish word for one, designating first epoch measurements. The CASA UNO experiment was the first civilian effort implementing a global GPS satellite tracking network. …

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The Extended Tracking Network And Indications Of Baseline Precision And Accuracy In The North Andes, Jeffrey T. Freymueller, James N. Kellogg Mar 1990

The Extended Tracking Network And Indications Of Baseline Precision And Accuracy In The North Andes, Jeffrey T. Freymueller, James N. Kellogg

Faculty Publications

The CASA UNO Global Positioning System (GPS) experiment (January-February 1988) included an extended tracking network which covered three continents in addition to the network of scientific interest in Central and South America. The repeatability of long baselines (400-1000 km) in South America is improved by up to a factor of two in the horizontal vector baseline components by using tracking stations in the Pacific and Europe to supplement stations in North America. In every case but one, the differences between the mean solutions obtained using different tracking networks was equal to or smaller than day-to-day rms repeatabilities for the same …

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