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1998

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Articles 1381 - 1410 of 2574

Full-Text Articles in Physical Sciences and Mathematics

Reservoir Rock Properties Of Middle Eocene Sandstones In Northern Thrace Basin, Nurettin Sonel, Aynur Geçer Büyükutku Jan 1998

Reservoir Rock Properties Of Middle Eocene Sandstones In Northern Thrace Basin, Nurettin Sonel, Aynur Geçer Büyükutku

Bulletin of the Mineral Research and Exploration

No abstract provided.


Theoretical Treatment Of Quasibound Resonances In Two-Color Resonant Four-Wave Mixing Spectroscopy, F. Di Teodoro, Elizabeth Mccormack Jan 1998

Theoretical Treatment Of Quasibound Resonances In Two-Color Resonant Four-Wave Mixing Spectroscopy, F. Di Teodoro, Elizabeth Mccormack

Physics Faculty Research and Scholarship

A treatment of continuum states in the application of diagrammatic perturbation theory to calculate the signal produced in two-color resonant four-wave mixing (TC-RFWM) spectroscopy is developed. The third-order susceptibility is significantly modified from that obtained when considering only discrete states. To illustrate the contribution of continuum states, the line profile of a quasibound resonance arising from the configuration interaction of bound and continuum states is derived. Analytic expressions for line profiles are presented for two specific experimental implementations of TC-RFWM used in gas-phase spectroscopic studies. While the TC-RFWM line profiles are found to be very distinct from the line profiles …


Phase And Risetime Dependence Using Rf Pulses In Multiphoton Processes, W. M. Griffith, Michael W. Noel, T. F. Gallagher Jan 1998

Phase And Risetime Dependence Using Rf Pulses In Multiphoton Processes, W. M. Griffith, Michael W. Noel, T. F. Gallagher

Physics Faculty Research and Scholarship

With this experiment we demonstrate that excitation of a two-state system with radio-frequency fields differing in phase by 90° produces nonintuitively different results, even for very long pulses. In addition, we show how the phase dependence of the transition probability of long pulses can be easily understood by using the single cycle time propagator. Finally, we have found surprising results for real pulses in the strong-field regime, i.e., pulses having appreciable rise and fall times.


On Subwavelet Sets., Eugen J. Ionascu Jan 1998

On Subwavelet Sets., Eugen J. Ionascu

Faculty Bibliography

Abstract. In this note we give a characterization of subwavelet sets and show that any point x ∈ R\0 has a neighborhood which is contained in a regularized wavelet set.


On The Unitary Systems Affiliated With Orthonormal Wavelet Theory In N-Dimensions, Eugen J. Ionascu Jan 1998

On The Unitary Systems Affiliated With Orthonormal Wavelet Theory In N-Dimensions, Eugen J. Ionascu

Faculty Bibliography

We consider systems of unitary operators on the complex Hilbert space L2 (Rn) of the form U :=UDA , Tv1 , ..., Tvn :=[DmT l1 v1 }}} Tln vn : m, l1 , ..., ln # Z], where DA is the unitary operator corresponding to dilation by an n_n real invertible matrix A and Tv1 , ..., Tvn are the unitary operators corresponding to translations by the vectors in a basis [v1 , ..., vn] for Rn . Orthonormal wavelets are vectors in L2 (Rn ) which are complete wandering vectors for U in the sense that [U: U # …


Optimal Renormalization Scale And Scheme For Exclusive Processes, Stanley J. Brodsky, Chueng-Ryong Ji, Alex Pang, David G. Robertson Jan 1998

Optimal Renormalization Scale And Scheme For Exclusive Processes, Stanley J. Brodsky, Chueng-Ryong Ji, Alex Pang, David G. Robertson

Physics Faculty Scholarship

We use the Brodsky-Lepage-Mackenzie (BLM) method to fix the renormalization scale of the QCD coupling in exclusive hadronic amplitudes such as the pion form factor and the photon-to-pion transition form factor at large momentum transfer. Renormalization-scheme-independent commensurate scale relations are established which connect the hard scattering subprocess amplitudes that control exclusive processes to other QCD observables such as the heavy quark potential and the electron-positron annihilation cross section. The commensurate scale relation connecting the heavy quark potential, as determined from lattice gauge theory, to the photon-to-pion transition form factor is in excellent agreement with γe⃗ π0e data assuming that the …


Novel Electronic And Magnetic Properties Of Ultrathin Chromium Oxide Films Grown On Pt(111), P S. Robbert, H Geisler, C A. Ventrice Jr, J Van Ek, S Chaturvedi, J A. Rodriguez, M Kuhn, U Diebold Jan 1998

Novel Electronic And Magnetic Properties Of Ultrathin Chromium Oxide Films Grown On Pt(111), P S. Robbert, H Geisler, C A. Ventrice Jr, J Van Ek, S Chaturvedi, J A. Rodriguez, M Kuhn, U Diebold

Physics Faculty Publications

The growth of epitaxial metal–oxide films on lattice-mismatched metal substrates often results in the formation of unique overlayer structures. In particular, epitaxial chromium oxide films grown on Pt(111) exhibit a p(2×2) symmetry through the first two monolayers of growth which is followed by a (√3×√3)R30° phase that is attributed to the growth of a Cr2O3(0001) overlayer. Ultraviolet photoelectron spectroscopy measurements have been performed on the CrOx/Pt(111) system. The electronic structures of CrO2, Cr2O3, and Cr3O4 were calculated using the linear muffin-tin orbital method in …


1998 Hampton Roads Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans Jan 1998

1998 Hampton Roads Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.


1998 Wachapreague Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans Jan 1998

1998 Wachapreague Station Tide Prediction Calendars, Virginia Institute Of Marine Science, David A. Evans

Miscellaneous

These calendars are produced monthly using David Evans' Tidecal.


Oil And Gas Map Of The Hazard 30 X 60 Minute Quadrangle, Kentucky, Brandon C. Nuttall Jan 1998

Oil And Gas Map Of The Hazard 30 X 60 Minute Quadrangle, Kentucky, Brandon C. Nuttall

Map and Chart--KGS

No abstract provided.


Oil And Gas Map Of The Evansville 30 X 60 Minute Quadrangle, Kentucky, Brandon C. Nuttall Jan 1998

Oil And Gas Map Of The Evansville 30 X 60 Minute Quadrangle, Kentucky, Brandon C. Nuttall

Map and Chart--KGS

No abstract provided.


Total Coal Thickness Of The Lower Elkhorn Coal In Eastern Kentucky, Ernest E. Thacker, Gerald A. Weisenfluh, William M. Andrews Jr. Jan 1998

Total Coal Thickness Of The Lower Elkhorn Coal In Eastern Kentucky, Ernest E. Thacker, Gerald A. Weisenfluh, William M. Andrews Jr.

Map and Chart--KGS

This map is one of a series that shows the regional characteristics of the Lower Elkhorn coal. The maps were prepared as part of the U.S. Geological Surveys National Coal Assessment Program, which compiles regional maps and databases that provide a comprehensive assessment of the most important coal beds in the nation. The Lower Elkhorn coal is one of the leading producers in the state of Kentucky and has, in some areas, a reputation as an excellent metallurgical-grade coal. It is known locally as the Pond Creek, Imboden, Path Fork, Blue Gem, Straight Creek, Bruin, or Vires coal bed. This …


Use Of Animal Wastes On Cropland, Monroe Rasnake, M. Scott Smith Jan 1998

Use Of Animal Wastes On Cropland, Monroe Rasnake, M. Scott Smith

Soil Science News and Views

In recent months, environmental issues relating to land application of animal and industrial wastes have been widely debated in Kentucky. On several occasions, members of the University of Kentucky Agronomy Department have been asked to provide scientific information and technical interpretation related to these complex and controversial issues. To be certain that the public and policy makers are provided with consistent and scientifically sound information, the Agronomy Department has decided to release consensus statements on some of the major agronomic issues involved. These statements reflect our best scientifically based interpretations of these important subjects. Several of our faculty with long …


Interactions Of Topological Kinks In Two Coupled Rings Of Nonlinear Oscillators, A E. Duwel, C P. Heij, J C. Weisenfeld, Stephen M.K. Yeung, E Trias, S. J.K. Vardy, H. S.J. Van Der Zant, S H. Strogatz, T P. Orlando Jan 1998

Interactions Of Topological Kinks In Two Coupled Rings Of Nonlinear Oscillators, A E. Duwel, C P. Heij, J C. Weisenfeld, Stephen M.K. Yeung, E Trias, S. J.K. Vardy, H. S.J. Van Der Zant, S H. Strogatz, T P. Orlando

Mathematics

Two discrete rings of nonlinear oscillators with topologically trapped kinks exhibit features due to coupling interactions between the rings. These interaction effects include phase locking between kinks in different rings, precession of the kink/antikink collision region, excitation of kink/antikink pairs, and time-dependent switching. We study these phenomena in simulations of two coupled discrete sine-Gordon equations, and in experiments on two inductively coupled rings of niobium Josephson junctions.


Exceptional Objects, John Stillwell Jan 1998

Exceptional Objects, John Stillwell

Mathematics

No abstract provided.


Trees Working In Western Australia, Dave Berry Jan 1998

Trees Working In Western Australia, Dave Berry

Journal of the Department of Agriculture, Western Australia, Series 4

There is an air of inevirability about farm forestry - no-one disputs that planting trees is a sure route to curbing agriculture's serious land degredation problem. Dave Berry talks with some of the key players developing the industry.


Western Australia Soil Acidity Research And Development Update 1998 : Time To Lime, Department Of Agriculture And Food, Western Australia Jan 1998

Western Australia Soil Acidity Research And Development Update 1998 : Time To Lime, Department Of Agriculture And Food, Western Australia

Bulletins 4000 -

Recent yield responses by canola where lime has been applied to acidic soils are very encouraging. Two sites have shown that the yield increase in canola after lime was applied in the previous year would have easily paid for the total cost of purchase, transport and application of the lime.

This work was carried out to demonstrate the increased options that are likely to be available once producers are treating or managing soil acidity. Canola is becoming increasingly important as a cash value crop and a break crop allowing wider rotations.

Growers are pushing the limits of canola’s tolerance to …


Geophysical Characterization, Redox Zonation, And Contaminant Distribution At A Groundwater/Surface Water Interface, John Lendvay, W A. Sauck, M L. Mccormick, M J. Barcelona, D H. Kampbell, J T. Wilson, P Adriaens Jan 1998

Geophysical Characterization, Redox Zonation, And Contaminant Distribution At A Groundwater/Surface Water Interface, John Lendvay, W A. Sauck, M L. Mccormick, M J. Barcelona, D H. Kampbell, J T. Wilson, P Adriaens

Environmental Science

Three transects along a groundwater/surface water interface were characterized for spatial distributions of chlorinated aliphatic hydrocarbons and geochemical conditions to evaluate the natural bioremediation potential of this environmental system. Partly on the basis of ground penetrating radar measurements, a conductive sediment layer was detected from the shore out to at least 300 m offshore which exhibited gradients in redox pairs and contaminant profiles. The cis-Dichloroethene and 1-chloroethene were predominant in the presence of elevated methane and ferrous iron concentrations and depressed sulfate and aquifer solids-bound iron concentrations. The shallow monitoring points were generally hypoxic to aerobic and exhibited values …


Dissociation Energies Of The Ga2, In2, And Gain Molecules, G Balducci, G Gigli, Giovanni Meloni Jan 1998

Dissociation Energies Of The Ga2, In2, And Gain Molecules, G Balducci, G Gigli, Giovanni Meloni

Chemistry Faculty Publications

The group III metal dimers Ga2 and In2 and the newly identified intermetallic molecule GaIn were investigated in a Knudsen cell-mass spectrometric study of the vapors over gallium–indium alloys. From the all-gas equilibria analyzed by the second-law and third-law methods the following dissociation energies were derived; D00 (Ga2)=110.8±4.9 kJ mol−1, D00 (In2)=74.4±5.7 kJ mol−1, D00 (GaIn)=90.7±3.7 kJ mol−1. The value here measured for the dissociation energy of In2 is discussed and compared with a previous experimental determination and with the results of more recent theoretical investigations.


Validating A Health Questionnaire For Predicting Neuropathy In Patients With Insulin-Dependent Diabetes Mellitus, Matthew J. Maurer Jan 1998

Validating A Health Questionnaire For Predicting Neuropathy In Patients With Insulin-Dependent Diabetes Mellitus, Matthew J. Maurer

Honors Theses, 1963-2015

Questionnaires are a cost-effective method for screening large numbers of people for health problems. More expensive clinical follow-up can focus on people whose responses to the questionnaire suggest they are most at risk. To my knowledge, no questionnaire has ever been developed to screen for neuropathy in diabetics. Using the questionnaire developed by Dr. Peter Cavanagh and Dr. Robert Van Deursen at the Center for Locomotion Studies (CELOS) at Penn State University, I was able to create a model from the questionnaire that predicts the presence of neuropathy.


Heraldry And Programming Languages: The Complexity Of Natural Languages Examined Through The Parsing Of The Heraldic Blazon, Hans A. Mersinger Jan 1998

Heraldry And Programming Languages: The Complexity Of Natural Languages Examined Through The Parsing Of The Heraldic Blazon, Hans A. Mersinger

Honors Theses, 1963-2015

The idea of programming computers to understand human speech and written text has been the dream, even the Holy Grail, of computer scientists and many others, since before the first computers where created. Computers in countless movies and television shows have been able to understand, and therefore interact with, the humans around them but until recently this possibility has been pure science fiction. By studying, and then attempting, the methods of parsing the heraldic language, one hopes to show some of the methods that are used to remove the ambiguity in natural languages that hamper their parsing. Given time, I …


Optical Properties Of Canopy Elements In Black Spruce, Jack Pine And Aspen Stands In Saskatchewan, Canada, Elizabeth A. Walter-Shea, Mark A. Mesarch Jan 1998

Optical Properties Of Canopy Elements In Black Spruce, Jack Pine And Aspen Stands In Saskatchewan, Canada, Elizabeth A. Walter-Shea, Mark A. Mesarch

School of Natural Resources: Faculty Publications

No abstract provided.


Unique Frontal Sinuses In Fossil And Living Hyaenidae (Mammalia, Carnivora): Description And Interpretation, R.M. Joeckel Jan 1998

Unique Frontal Sinuses In Fossil And Living Hyaenidae (Mammalia, Carnivora): Description And Interpretation, R.M. Joeckel

School of Natural Resources: Faculty Publications

No abstract provided.


The Moderate Resolution Imaging Spectroradiometer (Modis): Land Remote Sensing For Global Change Research, Christopher O. Justice, Eric Vermote, John R. G. Townshend, Ruth Defries, David P. Roy, Dorothy K. Hall, Vincent V. Salomonson, Jeffrey L. Privette, George Riggs, Alan Strahler, Wolfgang Lucht, Ranga P. Myneni, Yuri Knyazikhin, Steve W. Running, Rama R. Nemani, Zhengming Wan, Alfredo R. Huete, Wim Van Leeuwen, Robert E. Wolfe, Louis Giglio, Jan-Peter Muller, Philip Lewis, Michael J. Barnsley Jan 1998

The Moderate Resolution Imaging Spectroradiometer (Modis): Land Remote Sensing For Global Change Research, Christopher O. Justice, Eric Vermote, John R. G. Townshend, Ruth Defries, David P. Roy, Dorothy K. Hall, Vincent V. Salomonson, Jeffrey L. Privette, George Riggs, Alan Strahler, Wolfgang Lucht, Ranga P. Myneni, Yuri Knyazikhin, Steve W. Running, Rama R. Nemani, Zhengming Wan, Alfredo R. Huete, Wim Van Leeuwen, Robert E. Wolfe, Louis Giglio, Jan-Peter Muller, Philip Lewis, Michael J. Barnsley

United States National Aeronautics and Space Administration: Publications

The first Moderate Resolution Imaging Spectroradiometer (MODIS) instrument is planned for launch by NASA in 1998. This instrument will provide a new and improved capability for terrestrial satellite remote sensing aimed at meeting the needs of global change research. The MODIS standard products will provide new and improved tools for moderate resolution land surface monitoring. These higher order data products have been designed to remove the burden of certain common types of data processing from the user community and meet the more general needs of global-to-regional monitoring, modeling, and assessment. The near-daily coverage of moderate resolution data from MODIS, coupled …


Estimating Vegetation Structural Effects On Carbon Uptake Using Satellite Data Fusion And Inverse Modeling, Gregory P. Asner, C. Ann Bateson, Jeffrey L. Privette, Nazmi El Saleous, Carol A. Wessman Jan 1998

Estimating Vegetation Structural Effects On Carbon Uptake Using Satellite Data Fusion And Inverse Modeling, Gregory P. Asner, C. Ann Bateson, Jeffrey L. Privette, Nazmi El Saleous, Carol A. Wessman

United States National Aeronautics and Space Administration: Publications

Regional analyses of biogeochemical processes can benefit significantly from observational information on land cover, vegetation structure (e.g., leaf area index), and biophysical properties such as fractional PAR absorption. Few remote sensing efforts have provided a suite of plant attributes needed to link vegetation structure to ecosystem function at high spatial resolution. In arid and semiarid ecosystems (e.g., savannas), high spatial heterogeneity of land cover results in significant functional interaction between dominant vegetation types, requiring new approaches to resolve their structural characteristics for regional-scale biogeochemical research. We developed and tested a satellite data fusion and radiative transfer inverse modeling approach to …


A New Method Of Retrieving Surface Bidirectional Reflectance From Ground Measurements: Atmospheric Sensitivity Study, A. I. Lyapustin, J. L. Privette Jan 1998

A New Method Of Retrieving Surface Bidirectional Reflectance From Ground Measurements: Atmospheric Sensitivity Study, A. I. Lyapustin, J. L. Privette

United States National Aeronautics and Space Administration: Publications

Commonly, experimental data on surface directional reflectance are not properly corrected for atmospheric effects. In this paper, we describe a new method for rigorous retrieval of the bidirectional reflectance distribution function (BRDF) from ground-based measurements.


Assessment Of Urban Heat Islands: A Multi-Sensor Perspective For The Dallas-Ft. Worth, Usa Region, Kevin P. Gallo, Timothy W. Owen Jan 1998

Assessment Of Urban Heat Islands: A Multi-Sensor Perspective For The Dallas-Ft. Worth, Usa Region, Kevin P. Gallo, Timothy W. Owen

School of Natural Resources: Faculty Publications

Data acquired during the early to mid-1990s by several satellite-sensor systems were combined in an assessment of the urban heat-island effect for the Dallas-Fort Worth, TX region of the United States. Normalized difference vegetation index and radiant surface temperature were computed from NOAA-AVHRR data. Two measures of the anthropogenic light emitted by urban-related surface features were available from the DMSP-OLS. Landsat MSS data were used to provide estimates of the predominant land cover within the grid cells associated with the NOA-AVHRR and DMSP-OLS data. The multi-sensor analysis of the environment associated with seven climate observation stations in the Dallas-Ft. Worth …


Using Avhrr Data For Quantitative Estimation Of Vegetation Conditions: Calibration And Validation, Anatoly A. Gitelson, Felix Kogan, E. Zakarin, L. Spivak, L. Lebed Jan 1998

Using Avhrr Data For Quantitative Estimation Of Vegetation Conditions: Calibration And Validation, Anatoly A. Gitelson, Felix Kogan, E. Zakarin, L. Spivak, L. Lebed

School of Natural Resources: Faculty Publications

NDVI-derived Vegetation Condition Index (VCI) was compared with vegetation density, biomass and reflectance measured in the fields. The VCI numerically estimates fluctuation of NDVI related to intra-annual weather change only and is a measure of weather impact on vegetation. Test fields were located in different climatic (annual precipitation 150-700 mm) and ecological zones (semi-desert to steppe-forest) with elevation from 200 to 700 m in Kazakhstan. A range of NDVI variation was from 0.05 to 0.47. The determination coefficient between AVHRR-derived vegetation state and actually measured vegetation density of more than 0.76 was achieved. For the first time it was shown …


Windbreak Renovation, Craig Stange, Jon Wilson, James R. Brandle, Mike Kuhns Jan 1998

Windbreak Renovation, Craig Stange, Jon Wilson, James R. Brandle, Mike Kuhns

School of Natural Resources: Faculty Publications

Windbreaks are an integral part of many farms and ranches and provide critical protection for farmsteads, livestock and crops. Unfortunately, many windbreaks planted in the 1930s and 1940s are losing their effectiveness due to age, poor health or neglect. In some cases, the windbreak no longer has the necessary density to provide winter protection. In other cases, overcrowding may have reduced the health and vigor of the windbreak, or the windbreak may have been invaded by aggressive sod-forming grasses such as smooth brome, reducing tree growth. Whatever the reason, many older windbreaks need renovation.

All windbreaks, even well-designed ones, need …


Petrographic And Chemical Properties Of Carboniferous Resinite From The Herrin No. 6 Coal Seam, John C. Crelling, Michael A. Kruge Jan 1998

Petrographic And Chemical Properties Of Carboniferous Resinite From The Herrin No. 6 Coal Seam, John C. Crelling, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Resinite is a naturally occurring substance found in coal and derived from original plant resins. It is ubiquitous in North American coals and comprises 1 to 4% by volume of most Illinois coals. It has been commercially exploited in the western USA for use in adhesives, varnishes and thermal-setting inks. The major objectives of this study were: (1) to separate resinite macerals from the Herrin No. 6 coal seam and to carefully verify, by petrographic and fluorescence microspectrophotometric methods, that the separated material was indeed resinite; (2) to characterize the chemical composition of the separated resinite by Py–GC–MS techniques; and …