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1995

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Articles 1651 - 1680 of 2193

Full-Text Articles in Physical Sciences and Mathematics

Hart's Critics On Defeasible Concepts And Ascriptivism, Ronald P. Loui Jan 1995

Hart's Critics On Defeasible Concepts And Ascriptivism, Ronald P. Loui

All Computer Science and Engineering Research

Hart's "Ascription of Responsibility and Rights" is where we find perhaps the first clear pronouncement of defeasibility and the technical introduction of the term. The paper has been criticised, disavowed, and never quite fully redeemed. Its lurid history is now being used as an excuse for dismissing the importance of defeasibility. Quite to the contrary, Hart's introduction of defeasibility has uniformly been regarded as the most agreeable part of the paper. The critics' wish that defeasibility could be better expounded along the lines of a Wittgensteinian game-theoretic semantics has largely been fulfilled. Even the most contentious part of the paper, …

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Synchronized Data Objects, Marin Bezic Jan 1995

Synchronized Data Objects, Marin Bezic

All Computer Science and Engineering Research

Synchronized Data Objects (SDOs) are presented as a method of encapsulating, in the datatype definition, synchronization protocols that are used to control information exchange. SDOs are presented in the context of I/O abstraction, a programming model that seeks to separate communication from computation in order to support dynamic end-user configuration of distrivuted applications. SDOs can be used to implement a variety of synchronization paradigms, including remote invalidation, demand-driven data streams, remote procedure call, and promises. An implementation of SDOs is described in the context of The Programmers' Playground, a distributed application development environment that supports the I/O abstraction programming model. …

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Design Of A Tool For Rapid Prototyping Of Communication Protocols, Aniruddha Gokhale, Ron Cytron, George Varghese Jan 1995

Design Of A Tool For Rapid Prototyping Of Communication Protocols, Aniruddha Gokhale, Ron Cytron, George Varghese

All Computer Science and Engineering Research

We present a new tool for automatically generating prototypes of communication protocols on a wide variety of platforms. Our goal is to reduce design time, enhance portability, and accommodate optimizations automatically. Users of the tool are required to provide an abstract implementation of the protocol in C++ without worrying about the underlying operating system specific system calls. Instead, the user employs high-level interface functions provided by the tool to interact with the underlying operating system. Users also need not worry about complex packet formats that involve fields of various bit and byte lengths. Instead, they use simple C/C++ struct declarations …

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Structure Of Woody Riparian Vegetation In Great Basin National Park, S. D. Smith, K. J. Murray, F. H. Landau, A. M. Sala Jan 1995

Structure Of Woody Riparian Vegetation In Great Basin National Park, S. D. Smith, K. J. Murray, F. H. Landau, A. M. Sala

Life Sciences Faculty Research

The community composition and population structure of the woody riparian vegetation in Great Basin National Park are described. Community analyses were accomplished by sampling 229 plots along an elevational gradient of 8 major stream systems in the Park. TWINSPAN analysis identified 4 primary species groups that were characterized by Populus tremuloides (aspen), Abies concolor (white fir), Rosa woodsii (Woods rose), and Populus angustifolia (narrowleaf cottonwood) as dominants, respectively. Detrended Correspondence Analysis (DECORANA) showed that the most important environmental factors associated with the distribution of species were elevation and slope, with flood-related physiographic factors having a secondary effect. Analysis of size-class …

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A Trainable, Single-Pass Algorithm For Column Segmentation, Son Sylwester, Sharad C. Seth Jan 1995

A Trainable, Single-Pass Algorithm For Column Segmentation, Son Sylwester, Sharad C. Seth

CSE Conference and Workshop Papers

Column Segmentation logically precedes OCR in the document analysis process. The trainable algorithm described here, XYCUT, relies on horizontal and vertical binary profiles to produce an XY- tree representing the column structure of a page of a technical document in a single pass through the bit image. Training against ground truth adjusts a single, resolution independent, parameter using only local information and guided by an edit distance function. The algorithm correctly segments the page image for a (fairly) wide range of parameter values, although small, local and repairable errors may be made, an effect measured by a repair cost function.

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Neutron Investigations Of Novel Magnetic Phases, William B. Yelon Jan 1995

Neutron Investigations Of Novel Magnetic Phases, William B. Yelon

Physics Faculty Research & Creative Works

Recent years have seen a renewed search for Fe based permanent magnets, spurred by the discovery of Nd2Fe14B and interstitially modified rare-earth iron binaries. The insights derived from those compounds have suggested a number of routes to the development of such systems, including selective site substitution and combinations of site substitution and interstitial modification. Neutron diffraction is an essential component of this work, since it provides systematic information about the location of substitutional and interstitial atoms, and about the effects these changes have on the magnetic interactions in the systems of interest

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Measurements Of Fast Confined Alphas On Tftr, R. K. Fisher, J. M. Mcchesney, P. B. Parks, H. H. Duong, S. S. Medley, A. L. Roquemore, D. K. Mansfield, R. V. Budny, M. P. Petrov, Ronald E. Olson Jan 1995

Measurements Of Fast Confined Alphas On Tftr, R. K. Fisher, J. M. Mcchesney, P. B. Parks, H. H. Duong, S. S. Medley, A. L. Roquemore, D. K. Mansfield, R. V. Budny, M. P. Petrov, Ronald E. Olson

Physics Faculty Research & Creative Works

This Letter reports the first measurements of the fast confined α-particle energy distribution in a fusion plasma. The pellet charge exchange technique shows the fusion generated α's in the core of the Tokamak Fusion Test Reactor plasma slow down classically, and appear to be well confined. Preliminary indications are that stochastic ripple effects are responsible for steepening the energy distribution outside the plasma core (r/a0.35). Sawteeth mixing of fast α's is suggested in data during the post-beam-heating plasma decay. © 1995 The American Physical Society.

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Semiempirical Model For The Electrical Properties Of La1-Xcaxcoo3, S. R. Sehlin, Harlan U. Anderson, Don M. Sparlin Jan 1995

Semiempirical Model For The Electrical Properties Of La1-Xcaxcoo3, S. R. Sehlin, Harlan U. Anderson, Don M. Sparlin

Materials Science and Engineering Faculty Research & Creative Works

A semiempirical model of the Seebeck coefficient for a small polaron hopping conductor is presented. The population of small polarons is allowed to change as a function of temperature via the mechanism of charge disproportionation. The energy required for polaron formation by the disproportionation mechanism is modeled as screened by a Coulomb interaction with nearby small polarons. The charge carrier site occupancies generated by the model are used to successfully predict the electrical conductivity and Seebeck coefficient for compositions in the La1-xCaxCoO3 system. Cobalt ion valence populations predicted by the model are used to calculate effective paramagnetic moments for LaCoO3, …

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Structure And Electrical Properties Of La1-Xsrxco1-Yfeyo3. Part 1. The System La0.8sr0.2co1-Yfeyo3, L. W. Tai, M. M. Nasrallah, Harlan U. Anderson, Don M. Sparlin, S. R. Sehlin Jan 1995

Structure And Electrical Properties Of La1-Xsrxco1-Yfeyo3. Part 1. The System La0.8sr0.2co1-Yfeyo3, L. W. Tai, M. M. Nasrallah, Harlan U. Anderson, Don M. Sparlin, S. R. Sehlin

Materials Science and Engineering Faculty Research & Creative Works

Crystal structure, thermal expansion, thermogravimetry, thermoelectricity, and electrical conductivity of compositions in the system La0.8Sr0.2Co1-yFeyO3 with 0 ≤ y ≤ 1 were studied as function of Co Fe ratio and temperature, in air. The electrical conduction mechanism is attributed to the adiabatic-hopping of p-type small polarons. At high temperatures, oxygen deficiency causes lattice expansion and a reduction in electrical conductivity. The observed temperature dependence of the Seebeck coefficient is attributed to changes in carrier concentration caused by a thermally excited charge disproportionation of Co3+ ions and by the ionic compensation of induced oxygen vacancies. The measured electrical conductivity and Seebeck …

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Intercomparison Between Commercial Condensation Nucleus Counters And An Alternating Temperature Gradient Cloud Chamber, Darryl J. Alofs, C. K. Lutrus, Donald E. Hagen Jan 1995

Intercomparison Between Commercial Condensation Nucleus Counters And An Alternating Temperature Gradient Cloud Chamber, Darryl J. Alofs, C. K. Lutrus, Donald E. Hagen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Three Commercial CNC Counters (TSI Models 3010, 3022A, and 3025A) Are Compared with an Alternating Temperature Gradient Cloud Chamber (ALGR). Electrically Size Classified Aerosols of Sodium Chloride and Silver Are Used. Diffusional Losses within the ALGR Are Much Larger Than for the TSI Instruments: Therefore the ALGR Concentrations Are Corrected for Internal Diffusional Losses, But the TSI Instruments Are Not. the Particle Size Range Tested is 4–90 Nm. for Sodium Chloride, the TSI Concentrations Agreed Fairly Well with the Corrected ALGR at Larger Sizes, and Were Below the Corrected ALGR at Smaller Sizes. the Electrical Aerosol Classifier (EAC) Setting at …

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Projectile Energy Loss In Multiply Ionizing Ion-Atom Collisions, Harald Schone, Reinhold S. Schuch, Sheldon Datz, Michael Schulz, Peter F. Dittner, J. P. Giese, Quentin C. Kessel, Herbert F. Krause, Philip D. Miller, Charles Randy Vane Jan 1995

Projectile Energy Loss In Multiply Ionizing Ion-Atom Collisions, Harald Schone, Reinhold S. Schuch, Sheldon Datz, Michael Schulz, Peter F. Dittner, J. P. Giese, Quentin C. Kessel, Herbert F. Krause, Philip D. Miller, Charles Randy Vane

Physics Faculty Research & Creative Works

The projectile energy loss for 7.5--25-MeV C6+,5+ and F6+ ions was measured for single collisions with He, Ne, Ar, and Kr as a function of the recoil-ion charge state and the projectile scattering. This energy loss was measured for collisions in which the projectile captured an electron and for those involving just direct ionization. We investigated and found a large average energy transfer (100--250 eV/electron) to the continuum electrons. A strong increase of the scattering angle with recoil-ion charge state was observed for both capture and direct ionization. The results imply that, for smaller impact parameters, higher recoil-ion …

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Lattice- And Molecular-Dynamics Studies Of Rbliso4, V. Katkanant, John R. Hardy Jan 1995

Lattice- And Molecular-Dynamics Studies Of Rbliso4, V. Katkanant, John R. Hardy

John R. Hardy Papers

Using our previously developed method for calculating parameter-free potential-energy surfaces for ionic molecular crystals, specifically sulfates, we study phase transitions in RbLiSO4 by means of lattice and molecular dynamics. We found that the high-temperature phase I (Pnam) is highly unstable and transforms to the observed lower temperature phase VI (P1121/n) at about 475–525 K. Compared with isomorphous CsLiSO4, there are more branches of unstable modes in the Pnam phase for RbLiSO4. The maximum instability of these modes occurs away from the zone center, q=(0.118a*,0,0), which implies that a high-order …

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Behavior Of The Solutions To A Functional Equation Which Equates A Function's Inverse To Its Reciprocal, Robert Rudolph Anschuetz Jan 1995

Behavior Of The Solutions To A Functional Equation Which Equates A Function's Inverse To Its Reciprocal, Robert Rudolph Anschuetz

Retrospective Theses and Dissertations

This thesis explores the behavior of solutions of the functional equation f-1(x)= 1/f(x) for x ε Dom(f), where f is a real-valued function of a real variable. It is quite common to mistake the notation f-1, which means the inverse of f with respect to composition with the inverse of f with respect to multiplication, usually denoted by 1/f. This thesis shows that although f-1 and 1/f are usually different function, they do indeed sometimes represent the same function. This thesis will also provide …

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Constraints On Present-Day Basin And Range Deformation From Space Geodesy, Timothy H. Dixon, Stefano Robaudo, Jeffrey Lee, Marith C. Reheis Jan 1995

Constraints On Present-Day Basin And Range Deformation From Space Geodesy, Timothy H. Dixon, Stefano Robaudo, Jeffrey Lee, Marith C. Reheis

School of Geosciences Faculty and Staff Publications

We use new space geodetic data from very long baseline interferometry and satellite laser ranging combined with other geodetic and geologic data to study contemporary deformation in the Basin and Range province of the western United States. Northwest motion of the central Sierra Nevada block relative to stable North America, a measure of integrated Basin and Range deformation, is 12.1±1.2 mm/yr oriented N38°W±5° (one standard error), in agreement with previous geological estimates within uncertainties. This velocity reflects both east-west extension concentrated in the eastern Basin and Range and north-northwest directed right lateral shear concentrated in the western Basin and Range. …

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Approximation Algorithms: Good Solutions To Hard Problems, Ran Libeskind-Hadas Jan 1995

Approximation Algorithms: Good Solutions To Hard Problems, Ran Libeskind-Hadas

All HMC Faculty Publications and Research

Consider a computer network represented by an undirected graph where the vertices represent computer nodes and the edges represent links between the nodes. Since some of the links in the network may become faulty, link testing devices are placed at some of the nodes. A tester at a particular node can test all links incident to that node. Since the testers are expensive, however, we wish to deploy the minimum number of these devices such that every link is incidient to at least one node containing a tester. In graph theoretic terms, a vertex cover is a subset of the …

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Optical Measurements Of The Core Radius Of High-Δ Fibers With 1-Nm Resolution, Peter N. Saeta Jan 1995

Optical Measurements Of The Core Radius Of High-Δ Fibers With 1-Nm Resolution, Peter N. Saeta

All HMC Faculty Publications and Research

An optical technique for measuring the core radius of high-Δ optical fibers is described. Variations in the core radius of step-index fibers can be measured down to a scale of 1 nm.

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A Simple Technique To Measure Stress In Ultrathin Films During Growth, D. Sander, Axel Enders, J. Kirschner Jan 1995

A Simple Technique To Measure Stress In Ultrathin Films During Growth, D. Sander, Axel Enders, J. Kirschner

Axel Enders Publications

We demonstrate an easy implementation of the cantilever bending beam approach to measure stress during film growth in ultrahigh vacuum. Using a simple and compact optical deflection technique, film stress with sub-monolayer sensitivity can be detected. A stress measurement during FeSi, formation on Si(l11) is presented.

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Arkansas' Wellhead Protection Program, With Discussion Of Delineation Methodology, Robert Cordova, Bobby Makin Jan 1995

Arkansas' Wellhead Protection Program, With Discussion Of Delineation Methodology, Robert Cordova, Bobby Makin

Journal of the Arkansas Academy of Science

The Wellhead Protection (WHP) program was authorized by the 1986 Amendments to the Safe Drinking Water Act. The Arkansas Department of Health in July, 1986, was designated by Governor Clinton to be the lead agency in carrying out the WHP program. The program is designed to protect the ground-water resource tapped by public water-supply wells from contaminants which are injurious to the public health. It is the first formal attempt by the federal government in its environmental protection role to prevent contamination from taking place, in contrast to costly clean-up or remediation programs. Among its several requirements, the program includes: …

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Hammett Correlations Of Carbonyl 13c Chemical Shifts In A Series Of N-(4-Substituted Phenyl)-6-Chloro-5-Fluoronicotinamides, Frank L. Setliff, John W. Hawley, Alan D. Toland Jan 1995

Hammett Correlations Of Carbonyl 13c Chemical Shifts In A Series Of N-(4-Substituted Phenyl)-6-Chloro-5-Fluoronicotinamides, Frank L. Setliff, John W. Hawley, Alan D. Toland

Journal of the Arkansas Academy of Science

A series of nine N-(4-substituted phenyl)-6-chloro-5- fluoronicotinamides exhibited excellent correlations of their carbonyl 13C shifts (5CO,ppm as measured in DMSO) with the standard Hammett substituent constants (c?R) of the substituent inthe 4-position. The linear relationship was defined by the equation 8CO ¦ 1.22

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Spectroscopic Temperature Measurements For A Direct Current Arcjet Diamond Chemical Vapor Deposition Reactor, Scott W. Reeve, Wayne A. Weimer Jan 1995

Spectroscopic Temperature Measurements For A Direct Current Arcjet Diamond Chemical Vapor Deposition Reactor, Scott W. Reeve, Wayne A. Weimer

Journal of the Arkansas Academy of Science

The diamond thin filmcommercial market isprojected to exceed one billion dollars by the year 2000. Potential applications of diamond thin films range from cutting tools to electronics tomedical devices. The explosion ofinterest in this fieldresults from the extreme properties diamond possesses: itis the hardest material known toman and yet, has a coefficient of friction similar to Teflon;its ability to conduct heat is five times that of copper; and diamond is completely inert. However, despite the tremendous economic incentive, there are still several technological barriers preventing diamond filmscale-up to commercial production. Included among these are a fundamental understanding of the gas …

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Alkaline Phosphatase Activity And Phosphorus Limitation In Marine Macroalgae From The Florida Keys And The Bahamas, Christine M. Urnezis Jan 1995

Alkaline Phosphatase Activity And Phosphorus Limitation In Marine Macroalgae From The Florida Keys And The Bahamas, Christine M. Urnezis

HCNSO Student Theses and Dissertations

Anthropogenic nutrient enrichment and coastal eutrophication are a primary threat to the biological integrity of coral reef ecosystems. Macroalgal blooms are one symptom of eutrophication and provide useful 'bioindicators' of the nutrient dynamics associated with the eutrophication process. This study used marine macroalgae to monitor physiological processes associated with eutrophication by comparing the degree of phosphorus (P) limitation in reef and nearshore environments of the highly developed Florida Keys with the relatively pristine Bahamas by measuring enzymatic alkaline phosphatase activity (APA), tissue composition, and water column nutrient concentrations [total nitrogen (TN) and total phosphorus (TP)]. Experimental nutrient enrichment studies were …

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Carbonate Deposition, Pyramid Lake Subbasin, Nevada: 2. Lake Levels And Polar Jet Stream Positions Reconstructed From Radiocarbon Ages And Elevations Of Carbonates (Tufas) Deposited In The Lahontan Basin, Larry Benson, Michaele Kashgarian, Meyer Rubin Jan 1995

Carbonate Deposition, Pyramid Lake Subbasin, Nevada: 2. Lake Levels And Polar Jet Stream Positions Reconstructed From Radiocarbon Ages And Elevations Of Carbonates (Tufas) Deposited In The Lahontan Basin, Larry Benson, Michaele Kashgarian, Meyer Rubin

United States Geological Survey: Staff Publications

Most of the tufas in the Pyramid Lake subbasin were deposited within the last 35,000 yr, including most of the mound tufas that border the existing lake. Many of the older tufas (> 21,000 yr B.P.) contained in the mounds were formed in association with ground-water discharge. The radiocarbon (14C) ages of the older tufas represent maximum estimates of the time of their formation. Lake Lahontan experienced large and abrupt rises in level at ~ 22,000, 15,000, and 11,000 yr B.P. and three abrupt recessions in level at ~ 16,000, 13,600, and 10,000 yr B.P. The lake-level rises …

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Kinetics Of Pressure Solution At Halite-Silica Interfaces And Intergranular Clay Films, Stephen H. Hickman, Brian Evans Jan 1995

Kinetics Of Pressure Solution At Halite-Silica Interfaces And Intergranular Clay Films, Stephen H. Hickman, Brian Evans

United States Geological Survey: Staff Publications

Pressure solution is widely regarded as a potentially important deformation
mechanism along crustal faults and during a diagenesis, yet the mechanisms and kinetics of this process remain highly controversial. To better understand the fundamental factors controlling the rates of pressure solution at the grain-to-grain scale, we conducted experiments in which convex halite lenses were pressed against fiats of fused silica in brine. Fluid pressures were maintained at 0.1 MPa; temperatures and mean contact normal stresses ranged from 8.3 ° to 90.2 °C and 0.5 to 13.5 MPa, respectively. The geometry and growth rate of the contact spot between the two …

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Evidence Of Active Dune Sand On The Great Plains In The 19th Century From Accounts Of Early Explorers, Daniel R. Muhs, Vance T. Holliday Jan 1995

Evidence Of Active Dune Sand On The Great Plains In The 19th Century From Accounts Of Early Explorers, Daniel R. Muhs, Vance T. Holliday

United States Geological Survey: Staff Publications

Eolian sand is extensive over the Great Plains of North America, but is at present mostly stabilized by vegetation. Accounts published by early explorers, however, indicate that at least parts of dune fields in Nebraska, Colorado, Kansas, New Mexico, and Texas were active in the 19th century. Based on an index of dune mobility and a regional tree-ring record, the probable causes for these periods of greater eolian activity are droughts, accompanied by higher temperatures, which greatly lowered the precipitationto- evapotranspiration ratio and diminished the cover of stabilizing vegetation. In addition, observations by several explorers, and previous historical studies, indicate …

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Geomorphic And Geochemical Evidence For The Source Of Sand In The Algodones Dunes, Colorado Desert, Southeastern California, Daniel R. Muhs, Charles A. Bush, Scott D. Cowherd, Shannon Mahan Jan 1995

Geomorphic And Geochemical Evidence For The Source Of Sand In The Algodones Dunes, Colorado Desert, Southeastern California, Daniel R. Muhs, Charles A. Bush, Scott D. Cowherd, Shannon Mahan

United States Geological Survey: Staff Publications

The Algodones dunes of southeastern California comprise one of the largest active dune fields in the United States. The source of sand of the Algodones dunes is controversial, and the source of stabilized aeolian sand in the adjacent East Mesa area has not been investigated at all. We used mineralogical compositions and trace element concentrations to ascertain the most likely source of sand for these active and stabilized dunes. Results indicate that alluvium derived from the San Bernardino Mountains, which enters the Salton trough to the northwest of the dune fields, and alluvium derived from the Chocolate Mountains, which is …

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Risk Assessment Plan For Petroleum Underground Storage Tanks In Kentucky, Part Ll: Diesel, Heating Oil, Other Middle Distillates And Waste Oil, Wesley J. Birge, A. J. Grant, J. R. Shaw, M. D. Kercher, D. P. Keogh Jan 1995

Risk Assessment Plan For Petroleum Underground Storage Tanks In Kentucky, Part Ll: Diesel, Heating Oil, Other Middle Distillates And Waste Oil, Wesley J. Birge, A. J. Grant, J. R. Shaw, M. D. Kercher, D. P. Keogh

KWRRI Research Reports

This report consists of an appendix :Risk Assessment Plan for Petroleum Underground Storage Tanks in Kentucky and a second appendix: Environmental Half-Life and Ecological Effects of PAHs

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Cso Impact Assessment For Banklick Creek, Lindell E. Ormsbee, A. Reddy, S. Gruzesky, A. Jain Jan 1995

Cso Impact Assessment For Banklick Creek, Lindell E. Ormsbee, A. Reddy, S. Gruzesky, A. Jain

KWRRI Research Reports

This report contains the results of a combined sewer overflow (CSO) impact assessment study for Banklick Creek, which flows into the Licking River just south of Covington, Kentucky in Kenton County, Kentucky. This study is a component of a larger study that was conducted to determine the general impact of CSOs in the Northern Kentucky Region. The study was conducted through the Kentucky Water Resource Research Institute of the University of Kentucky and was funded by the Kentucky Natural Resources and Environmental Protection Cabinet through a grant from the United States Environmental Protection Agency.

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Optical Measurements On The Bp Iii To Isotropic Phase Transition In Highly Chiral Liquid Crystals, Jonathan Brent Becker , '92, Peter J. Collings Jan 1995

Optical Measurements On The Bp Iii To Isotropic Phase Transition In Highly Chiral Liquid Crystals, Jonathan Brent Becker , '92, Peter J. Collings

Physics & Astronomy Faculty Works

Optical activity and light scattering measurements in the chiral-racemic system of 4-(2-methylbutyl) phenyl-4-hexyloxybenzoate (CE4) reveal a much larger decrease in the discontinuity at the third blue phase (BP III) to isotropic phase transition than reported previously using adiabatic scanning calorimetry on another compound. Whereas these new data show that the transition is still slightly discontinuous for the pure optical isomer of CE4, similar light scattering measurements on the pure optical isomer of 4″-(2- methylbutylphenyl)-4′-(2-methylbutyl)-4-biphenyl-carboxylate (CE2), which is more chiral than CE4, show no discontinuity at all.

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Trace And Eigenvalue Inequalities Of Ordinary And Hadamard Products For Positive Semidefinite Hermitian Matrices, Bo-Ying Wang, Fuzhen Zhang Jan 1995

Trace And Eigenvalue Inequalities Of Ordinary And Hadamard Products For Positive Semidefinite Hermitian Matrices, Bo-Ying Wang, Fuzhen Zhang

Mathematics Faculty Articles

Let Aand Bbe $n \times n$ positive semidefinite Hermitian matrices, let $\alpha $ and $\beta $ be real numbers, let $ \circ $ denote the Hadamard product of matrices, and let $A_k $ denote any $k \times k$ principal submatrix of A. The following trace and eigenvalue inequalities are shown: \[ \operatorname{tr}(A \circ B)^\alpha \leq \operatorname{tr}(A^\alpha \circ B^\alpha ),\quad\alpha \leq 0\,{\text{ or }}\,\alpha \geq 1, \]\[ \operatorname{tr}(A \circ B)^\alpha \geq \operatorname{tr}(A^\alpha \circ B^\alpha ),\quad 0 \leq \alpha \leq 1, \]\[ \lambda^{1/ \alpha } (A^\alpha \circ B^\alpha ) \leq \lambda ^{1/\beta } (A^\beta \circ B^\beta ),\quad\alpha \leq \beta ,\alpha \beta \ne …

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Electronic Structures And Curie Temperatures Of Iron-Based Rare-Earth Permanent-Magnet Compounds , J.P. Woods , B.M. Patterson, A.S. Fernando, Sitaram Jaswal, D. Welipitiya, David J. Sellmyer Jan 1995

Electronic Structures And Curie Temperatures Of Iron-Based Rare-Earth Permanent-Magnet Compounds , J.P. Woods , B.M. Patterson, A.S. Fernando, Sitaram Jaswal, D. Welipitiya, David J. Sellmyer

David Sellmyer Publications

The modification of the electronic structures of Sm2Fe17-xAlxNy, NdFe11TiNy, and YFe12-xMox upon alloying and nitriding are examined with self-consistent spin-polarized calculations and soft-x-ray photoemission measurements between 18 and 135 eV. The changes in the Curie temperature Tc with substitutional modifications and nitrogen addition are modeled with self-consistent spin-polarized electronic structure calculations and the spin-fluctuation theory of Mohn and Wohlfarth which relates the electronic structure to Tc. The calculations show that the spin-summed density of states at the Fermi energy is related to …

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