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The Variations for Piano, Op. 27 of Anton Webern and the Quaderno musicale di Annalibera of Luigi Dallapiccola: A Lecture Recital, Together with Four Recitals of Selected Works of J.S. Bach, W.A. Mozart, F. Schubert, R. Schumann, J. Brahms, F. Chopin, A. Schoenberg, and M. Ravel

Description: The lecture recital was given on November 20, 1972. The discussion of Webern's Variations and Dallapiccola's Quaderno Musicale consisted of a analysis of the two works followed by a comparison of stylistic and performance aspects. The two works were then performed. In addition to the lecture recital four other public recitals were given. Two of these consisted entirely of solo literature for the piano. The third recital was a vocal chamber music recital and the fourth consisted of a piano concerto performed with an orchestra.
Date: May 1973
Creator: Bell, Digby
Partner: UNT Libraries

Thermal Selection at an Enzyme Locus in Populations of the Red Shiner, Notropis lutrensis, Receiving Hypolimnion Effluents from a Reservoir

Description: Genetic variation was examined at 19 loci encoding enzymatic and general proteins Notropis lutrensis from the Brazos River in Texas. The thermal regime of the Brazos River below Possum Kingdom Reservoir is altered due to the release of water from the hypolimnion. Summer water temperatures fluctuate as much as 7^oC. Levels of heterozygosity at the malate dehydrogenase-2 locus were correlated with the degree of water temperature fluctuation at each locality. The isozymes from three homozygous patterns of supernatant malate dehydrogenase (Mdh-l, Mdh-2) exhibited different activities at different experimental temperatures.
Date: May 1978
Creator: Richmond, M. Carol
Partner: UNT Libraries

Field shape of the accumulator LDA dipoles

Description: Large Aperture Dipoles (LDA) are used in the Fermilab Antiproton Accumulator to provide one half of the bending required for that storage ring. The production measurement data for those magnets are analyzed and the integrated field shape on the median plane at the design operating current (1,180 A) is reported. When linear (quadrupole) and parabolic (sextupole) terms are subtracted, the remaining field errors are only {approximately}10{sup {minus}4} over a {+-}4 inch aperture. Polynomial fits to that data can be interpreted in terms of normal harmonics of the magnetic field. However the polynomial fits are not unique. When the polynomial coefficients are expressed as harmonics with a reference radius of 1 inch, the nonlinear portions of this field (harmonics higher than quadrupole) are typically 10{sup {minus}5} to 10{sup {minus}6}. Both individual magnet results and statistical profiles are reported along with studies of the fitting limitations.
Date: May 1, 1996
Creator: Brown, B.C.
Partner: UNT Libraries Government Documents Department

What is the potential predictability of seasonal floods and droughts?

Description: The potential predictability (PP) of seasonal anomalies in continental hydrology may be thought of as the upper bound in forecast accuracy to be expected when the state of the oceans is known perfectly. We assume that the PP of the seasonal anomalies of continental hydrology is related to their degree of reproducibility in the presence of identical ocean boundary conditions across a number of simulations. In this study, the PP of seasonal anomalies in surface hydrological variables is estimated from an ensemble of 6 decadal integration of the ECMWF global atmospheric model coupled to a land-surface scheme which includes interception and transpiration by a simple vegetation canopy. Identical observed (AMIP) monthly sea surface temperatures are specified in each simulation, while the initial condition of the atmosphere and land surface are allowed to vary.
Date: May 1, 1996
Creator: Phillips, T.J.
Partner: UNT Libraries Government Documents Department

A study of the effect of nonrandom sampling on the estimation of exposure variability using exposure-time series from the OSHA IMIS health inspection database

Description: The objective of this study was to determine the effect of nonrandom sampling over time may have on the estimation of variability, namely the geometric standard deviation, using time series of personal exposure data.
Date: May 1, 1997
Creator: Martinez, L.T.
Partner: UNT Libraries Government Documents Department

Density equalizing map projections (cartograms) in public health applications

Description: In studying geographic disease distributions, one normally compares rates among arbitrarily defined geographic subareas (e.g. census tracts), thereby sacrificing some of the geographic detail of the original data. The sparser the data, the larger the subareas must be in order to calculate stable rates. This dilemma is avoided with the technique of Density Equalizing Map Projections (DEMP){copyright}. Boundaries of geographic subregions are adjusted to equalize population density over the entire study area. Case locations plotted on the transformed map should have a uniform distribution if the underlying disease risk is constant. On the transformed map, the statistical analysis of the observed distribution is greatly simplified. Even for sparse distributions, the statistical significance of a supposed disease cluster can be calculated with validity. The DEMP algorithm was applied to a data set previously analyzed with conventional techniques; namely, 401 childhood cancer cases in four counties of California. The distribution of cases on the transformed map was analyzed visually and statistically. To check the validity of the method, the identical analysis was performed on 401 artificial cases randomly generated under the assumption of uniform risk. No statistically significant evidence for geographic non-uniformity of rates was found, in agreement with the original analysis performed by the California Department of Health Services.
Date: May 1, 1998
Creator: Merrill, D.W.
Partner: UNT Libraries Government Documents Department

Decadal Arctic ice simulations: 1986-1995. Final report, September 1993--November 1997

Description: The Arctic ice cover has been simulated for the period 1986-1995 with two coupled ice-ocean models, one with low resolution on a small polar stereographic plane (PIPS1/O), and one with high resolution on a rotated spherical grid (PIPS2), covering all northern hemispheric sea ice. The ice model used was the Hibler ice model, and the ocean models were both z-level types with rigid lid. Atmospheric forcing were derived from surface fluxes computed by the Navy`s NOGAPS global atmospheric prediction model.
Date: May 1, 1997
Creator: Piacsek, S.; Preller, R. & Posey, P.
Partner: UNT Libraries Government Documents Department

Enhanced shortwave cloud radiative forcing due to anthropogenic aerosols

Description: It has been suggested that anthropogenic aerosols in the troposphere can influence the microphysical properties of clouds and in turn their reflectivity, thereby exerting a radiative influence on climate. This article presents the theoretical basis for of this so-called indirect forcing and reviews pertinent observational evidence and climate model calculations of its magnitude and geographical distribution. We restrict consideration to liquid-water clouds.
Date: May 1995
Creator: Schwartz, S. E. & Slingo, A.
Partner: UNT Libraries Government Documents Department

Photovoltaic module energy rating methodology development

Description: A consensus-based methodology to calculate the energy output of a PV module will be described in this paper. The methodology develops a simple measure of PV module performance that provides for a realistic estimate of how a module will perform in specific applications. The approach makes use of the weather data profiles that describe conditions throughout the US and emphasizes performance differences between various module types. An industry-representative Technical Review Committee has been assembled to provide feedback and guidance on the strawman and final approach used in developing the methodology.
Date: May 1996
Creator: Kroposki, B.; Myers, D.; Emery, K.; Mrig, L.; Whitaker, C. & Newmiller, J.
Partner: UNT Libraries Government Documents Department

Technical evaluation of two 6-kW mono-Si photovoltaic systems at the National Renewable Energy Laboratory

Description: This paper presents an analysis of performance data on the two 6-kW{sub ac} grid-connected photovoltaic systems at the National Renewable Energy Laboratory (NREL). The performance parameters analyzed include dc and ac power, aperture efficiency, energy, capacity factor and performance index which are compared to plane-of-array irradiance, ambient temperature, and back-of-module temperature as a function of time, either daily or monthly. Power ratings of the systems were also obtained for data corresponding to different test conditions. This study has shown, in addition to expected seasonal trends, that system monitoring is a valuable tool in assessing performance and detecting faulty equipment. In addition, methods applied for this study may be used to evaluate and compare systems employing different cell technologies.
Date: May 1, 1996
Creator: Dyk, E.E. van; Strand, T. & Hansen, R.
Partner: UNT Libraries Government Documents Department

The effect of horizontal resolution on cloud radiative forcing in the ECMWF model. PCMDI report No. 22

Description: With expanding computer capability and capacity there has been considerable interest in increasing the resolution in GCMs. The primary driving force behind this are two fold: (1) increased resolution may reduce the systematic errors inherent in parameterization of sub-grid scale processes, and (2) higher resolution may improve confidence in regional scale studies of climatic features that are orographically influenced -- such as the effect of the Tibetan Plateau on the East Asian Monsoon. This study focuses on the effect of horizontal resolution on the spatial and temporal systematic errors of cloud radiative forcing and its components. In this paper, the top-of-the-atmosphere radiation fields are taken from a series of simulations using the European Centre for Medium Range Forecasts (ECMWF) general circulation model (cycle 33), run at four different horizontal resolutions. Section 2 discusses the concept of cloud radiative forcing and describes the simulations from the ECMWF model. The observed global field of cloud forcing from ERBE is presented in section 3 along with the model-produced fields of the net solar and longwave cloud forcing. The seasonal effect of forcing is described in section 4, and the results are summarized in section 5.
Date: May 1, 1995
Creator: Potter, G.L.
Partner: UNT Libraries Government Documents Department

A Comparison of the Variation Technique Employed by Beethoven and Copland

Description: Aaron Copland was born of Russian-Jewish parents on November 14, 1900. Harris Kaplan, his father, had acquired the American equivalent of his name when an immigration official at the British port of entry wrote it on his papers, and from then on the family name was "Copland." Sarah Mittenthal and Harris Copland met at a family social gathering in New York and were married in 1885. They lived in the upper stories of his department store in Brooklyn which remained the family home until 1924 and was where Aaron, the youngest of five, was born.
Date: May 1964
Creator: Higginbotham, Mary Kay
Partner: UNT Libraries

Effects of Flaming Gorge Dam hydropower operations on flow and stage in the Green River, Utah and Colorado

Description: This report presents the development of Flaming Gorge Reservoir release patterns and resulting downstream flows and stages for four potential hydropower operational scenarios. The release patterns were developed for three representative hydrologic years: moderate, dry, and wet. Computer models were used to estimate flows and stages in the Green River resulting from these release patterns for the moderate water year. The four hydropower operational scenarios for Flaming Gorge Dam were year-round high fluctuating flows, seasonally adjusted high fluctuating flows, seasonally adjusted moderate fluctuating flows, and seasonally adjusted steady flows. The year-round high fluctuating flow scenario assumes that the monthly total reservoir releases would be the same as historical releases. The remaining seasonally adjusted flow scenarios would comply with the 1992 Biological Opinion of the US Fish and Wildlife Service, which requires high flows in the spring and limited hourly fluctuations, especially in summer and autumn releases, to protect endangered fish. Within one year, the maximum daily river stage fluctuations resulting from hydropower operations under the seasonally adjusted high fluctuating flow scenario would be similar to the maximum daily fluctuations under the year-round high fluctuating flow scenario. However, reduced or no fluctuations would occur in some time periods under the former scenario. The maximum daily river stage fluctuations under the seasonally adjusted moderate fluctuating flow scenario would be about half of those under the seasonally adjusted high fluctuating flow scenario.
Date: May 1, 1995
Creator: Yin, S.C.L.; Cho, H.E.; McCoy, J.J. & Palmer, S.C.
Partner: UNT Libraries Government Documents Department

Continuous, environmental radon monitoring program at the Yucca Mountain Site Characterization Project

Description: A continuous, environmental radon monitoring program has been established in support of the Department of Energy`s (DOE) Yucca Mountain Site Characterization Project (YMP). The monitoring program is to characterize the natural radon emissions at the YMP site, to understand the existing radon concentrations in the environmental background, and to assess and control the potential work exposure. Based upon a study of the monitoring results, this paper presents a preliminary understanding of the magnitudes, characteristics, and exposure levels of radon at the YMP site.
Date: May 1995
Creator: Liu, N.; Sorensen, C. D.; Tung, C. H. & Orchard, C. R.
Partner: UNT Libraries Government Documents Department

Hemicellulases from anaerobic thermophiles. Progress report

Description: The longterm goal of this research effort is to obtain an anaerobic thermophilic bacterium that efficiently converts various hemicellulose-containing biomass to ethanol over a broad pH range. The strategy is to modify the outfit and regulation of the rate-limiting xylanases, glycosidases and xylan esterases in the ethanologenic, anaerobic thermophile Thermoanaerobacter ethanolicus, which grows between pH 4.5 and 9.5. Although it utilizes xylans, the xylanase, acetyl(xylan) esterase and O-methylglucuronidase activities in T. ethanolicus are barely measurable and regarded as the rate limiting steps in its xylan utilization. Thus, and also due to the presently limited knowledge of hemicellulases in anaerobic thermophiles, we characterize the hemicellulolytic enzymes from this and other anaerobic thermophiles as enzyme donors. Beside the active xylosidase/arabinosidase from T. ethanolicus, exhibiting the two different activities, we characterized 2 xylosidases, two acetyl(xylan) esterases, and an O-methylglucuronidase from Thermoanaerobacterium spec. We will continue with the characterization of xylanases from novel isolated slightly acidophilic, neutrophilic and slightly alkalophilic thermophiles. We have cloned, subcloned and partially sequenced the 165,000 Da (2 x 85,000) xylosidase/arabinosidase from T. ethanolicus and started with the cloning of the esterases from Thermoanaerobacterium spec. Consequently, we will develop a shuttle vector and continue to apply electroporation of autoplasts as a method for cloning into T. ethanolicus.
Date: May 1, 1994
Creator: Wiegel, J.
Partner: UNT Libraries Government Documents Department

RESONANT X-RAY SCATTERING AS A PROBE OF ORBITAL AND CHARGE ORDERING.

Description: Resonant x-ray scattering is a powerful experimental technique for probing orbital and charge ordering. It involves tuning the incident photon energy to an absorption edge of the relevant ion and observing scattering at previously ''forbidden'' Bragg peaks, and it allows high-resolution, quantitative studies of orbital and charge order--even from small samples. Further, resonant x-ray scattering from orbitally ordered systems exhibits polarization- and azimuthal-dependent properties that provide additional information about the details of the orbital order that is difficult, or impossible, to obtain with any other technique. In the manganites, the sensitivity to charge and orbital ordering is enhanced when the incident photon energy is tuned near the Mn K absorption edge (6.539 keV), which is the lowest energy at which a 1s electron can be excited into an unoccupied state. In this process, the core electron is promoted to an intermediate excited state, which decays with the emission of a photon. The sensitivity to charge ordering is believed to be due to the small difference in K absorption edges of the Mn{sup 3+} and Mn{sup 4+} sites. For orbital ordering, the sensitivity arises from a splitting--or difference in the weight of the density of states [239]--of the orbitals occupied by the excited electron in the intermediate state. In the absence of such a splitting, there is no resonant enhancement of the scattering intensity. In principle, other absorption edges in which the intermediate state is anisotropic could be utilized, but the strong dipole transition to the Mn 4p levels--and their convenient energies for x-ray diffraction--make the K edge well-suited to studies of manganites. The Mn 4p levels are affected by the symmetry of the orbital ordering, which makes the technique sensitive to the orbital degree of freedom. Therefore resonant x-ray scattering can be used to obtain important quantitative information concerning the ...
Date: May 13, 2002
Creator: Nelson, C. S.; Hill, J. P. & Gibbs, D.
Partner: UNT Libraries Government Documents Department

Theme and Variations for Wind Ensemble

Description: A set of variations can be any length and contain any number of variations. The same set of variations also can be fashioned to resemble any musical form. On this basic premise, Theme and Variations for Wind Ensemble was written. It is a continuous one movement composition. There is a statement of a theme with five subsequent variations.
Date: May 1972
Creator: Hawkins, William A. (William Augustus)
Partner: UNT Libraries

OTEC thermal resource report for Jakarta, Indonesia

Description: The thermal resource south of Jakarta, Indonesia was studied for the area between 6--9/sup 0/ South latitude and 104--109/sup 0/ East longitude. The available thermal resource is an excellent one for OTEC exploitation. The mean surface temperature is very high, above 28/sup 0/C. An average monthly ..delta..T of 22.8/sup 0/C is available at a depth of 1000 meters. An annual average ..delta..T greater than 20.0/sup 0/C is available at 650 meters. Mean monthly temperatures at depths greater than 400 meters do not vary by more than 1/sup 0/C. The distance from the south coast of Java to the 1000- and 1500-meter depths is not prohibitive, with depths of 1000 meters available in less than 20 kilometers. The necessary depths to provide an adequate cold water supply are not available north of the island. The distance from Jakarta, on the north west coast of the island to water 1000 meters deep is quite large. A mixed layer exists throughout the year with small seasonal variation. High winds and storms are not major problems for OTEC development or operation. Surface circulation is fairly complex with variations throughout the year. Seismic activity is a problem for this site.
Date: May 1, 1979
Creator: Wolff, W. A.
Partner: UNT Libraries Government Documents Department

The structure of perturbative quantum gravity on a de Sitter background

Description: Classical gravitation on de Sitter space suffers from a linearization instability. One consequence is that the response to a spatially localized distribution of positive energy cannot be globally regular. We use this fact to show that no causal Green's function can give the correct linearized response to certain bilocalized distributions, even though these distributions obey the constraints of linearization stability. We avoid the problem by working on the open submanifold spanned by conformal coordinates. The retarded Green's function is first computed in a simple gauge, then the rest of the propagator is inferred by analyticity -- up to the usual ambiguity about real, analytic and homogeneous terms. We show that the latter can be chosen so as to give a propagator which does not grow in any direction. The ghost propagator is also given and the interaction vertices are worked out.
Date: May 1, 1992
Creator: Tsamis, N.C. (Crete Univ., Iraklion (Greece). Dept. of Physics) & Woodward, R.P. (Florida Univ., Gainesville, FL (United States). Dept. of Physics)
Partner: UNT Libraries Government Documents Department

Dworshak Dam Impact (Impacts) Assessment and Fishery Investigation.

Description: Kokanee abundance, estimated from July trawl data, was 1.2 million fish in 1988, including 553,000 fry, 501,000 yearlings and 156,000 subadults. Spawning trend data indicated escapement was up threefold compared to 1987, despite a sport harvest of 207,000 kokanee averaging 258 mm caught at a rate of 1.5 fish per hour. An estimated 40,000 kokanee were counted during the September peak of spawning in five tributaries of the reservoir. Size of adult fish was below average at 293 mm. Zooplankton densities averaged 10.3 organisms/L in 1988 and ranged from 0.3 organisms/L during April at the Little North Fork station to 26.2 organisms/L in November at the Elk Creek station. Densities were similar to values obtained prior to the development of the primary kokanee fishery; however, cladocerans made up only 34.9% of the zooplankton sampled. Daphnia and Cyclops were the most important food items; Daphnia became the prime food organism as its seasonal abundance increased. Concentrations of ortho-phosphate and nitrate, lower than in the 1970s, indicated Dworshak may have become more oligotrophic. 13 refs., 24 figs., 4 tabs.
Date: May 1, 1989
Creator: Mauser, Gregg
Partner: UNT Libraries Government Documents Department

Electrostatic turbulence and transport in the RFP edge

Description: This thesis details measurements of electrostatic turbulence and transport in the Madison Symmetric Torus reversed field pinch. The electrostatic fluctuation levels are found to be large, with {tilde n}{sub e}/n{sub e} {approximately} 30%--55% and {tilde T}{sub e}/T{sub e} {approximately} 15%--40%. The frequency and wavenumber spectra are broad, with {Delta}n {approximately} 70--150 and {Delta}m {approximately} 3--6, and differ from measured magnetic fluctuation spectra. The transport inferred from coherence measurements indicates that electrostatic fluctuations can account for most of the observed particle losses, but contribute only {approximately}20% to the observed electron energy loss.
Date: May 1, 1992
Creator: Spragins, C.W.
Partner: UNT Libraries Government Documents Department

Edge gradient and safety factor effects on electrostatic turbulent transport in tokamaks

Description: Electrostatic turbulence and transport measurements are performed on the Tokapole-II tokamak at the University of Wisconsin-Madison, as the safety-factor and the edge equilibrium gradients and varied substantially. Tokapole-II is a poloidal divertor tokamak capable of operating at a wide range of safety factors due to its unique magnetic limiter configuration. It also has retractable material limiters in a large scrape-off region, which permits the study of edge boundary conditions like density and temperature gradients. The turbulence is independent of safety factor, but strongly sensitive to the local density gradient, which itself depends upon the limiter configuration. When a material limiter is inserted in a high <qa> discharge, the density gradient is increased locally together with a local increase of the turbulence. On the other hand, limiter insertion in low <qa> discharges did not increase the density gradient as much and the turbulence properties are unchanged with respect to the magnetic limiter case. It is conducted then, that electrostatic turbulence is caused by the density gradient. Although the electrostatic fluctuation driven transport is enhanced in the large density gradient case, it is in all cases to small to explain the observed energy confinement times. To explore instabilities with small wavelengths, a 0.5 mm diameter shperical Langmuir probe was constructed, and its power compared with the power measured by larger cylindrical probes.
Date: May 1, 1992
Creator: Tan, Ing Hwie.
Partner: UNT Libraries Government Documents Department