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Some Information About SMPY (open access)

Some Information About SMPY

Paper describing the beginnings of the Study of Mathematically Precocious Youth at The Johns Hopkins University, including a list of books about the study, and a list of recipients of the bachelor's degree from The Johns Hopkins University at age 18 or younger.
Date: January 1987
Creator: unknown
System: The UNT Digital Library
[Newspaper Article: B'wood Harvey Girl in 'Texas Highways'] (open access)

[Newspaper Article: B'wood Harvey Girl in 'Texas Highways']

Newspaper article about Lillian Preas, a resident of Brownwood, Texas and former Harvey Girl whose story was used in the magazine Texas Highways.
Date: January 26, 1992
Creator: Graves, Harriette
System: The Portal to Texas History
["Wariness and Optimism Vie as Gays View New President" article, January 26, 2001] (open access)

["Wariness and Optimism Vie as Gays View New President" article, January 26, 2001]

An article written by Elizabeth Becker for the New York Times about the acknowledgement of the Republican Unity Coalition and inclusion of gay and lesbian people in ceremonies. The piece also speaks about the opinions of the new president George W. Bush and vice president Dick Cheney.
Date: January 26, 2001
Creator: Becker, Elizabeth
System: The UNT Digital Library
Reconstruction of False Spring Occurrence Over the Southeastern U.S., 1901–2007: Increasing Risk of Spring Freeze Damage? (open access)

Reconstruction of False Spring Occurrence Over the Southeastern U.S., 1901–2007: Increasing Risk of Spring Freeze Damage?

Near-record warmth over much of the United States during March 2007 promoted early growth of crops and vegetation. A widespread arctic air outbreak followed in early April, resulting in extensive agricultural losses over the southeastern U.S. This “false spring” event also resulted in widespread damage to newly grown tissues of native deciduous forest species, shown by previous researchers to have affected the terrestrial carbon cycle. The current study reconstructed the historical occurrence of false springs for the southeastern U.S. (32–39 °N; 75–98 °W) from 1901–2007 using daily maximum and minimum temperature records from 176 stations in the Global Historical Climatology Network database, and Enhanced Vegetation Index (EVI) data derived from Moderate Resolution Imaging Spectroradiometer (MODIS) satellite observations. A false spring index examined the relative timing of the start of the growing season (SGS), or leaf-out, to the timing of a potentially damaging last hard freeze (≤ -2.2 °C). SGS was modeled for the domain by combining EVI data with ground-based temperature “degree-day” calculations refl ecting the rate of springtime warming. No significant area-wide, long-term SGS trend was found (0.2 days later/decade; p = 0.3). However, the timing of the last hard freeze did occur significantly later (>1 day/decade; p < …
Date: January 1, 2009
Creator: Marino, Garrett P. & Kaiser, Dale P.
System: The UNT Digital Library
Controlling Gully Erosion with Earth Dams in North-Central Texas (open access)

Controlling Gully Erosion with Earth Dams in North-Central Texas

This article describes the use of earth dams for controlling gully erosion in part of the Eastern Cross Timbers of North-Central Texas.
Date: January 2001
Creator: Hudak, Paul F. & Chadbourne, John
System: The UNT Digital Library
[News advisory regarding press conference to discuss the official filing of a petition in Baker v. Wade] (open access)

[News advisory regarding press conference to discuss the official filing of a petition in Baker v. Wade]

News advisory regarding press conference to discuss the official filing of a petition for certiorari in Baker v. Wade appeals case.
Date: [1986-01-21..]
Creator: unknown
System: The UNT Digital Library
Habitat Quantity of Red-Cockaded Woodpecker Picoides Borealis (Aves: Piciformes: Picidae) in its Former Historic Landscape Near the Big Thicket Naitonal Preserve, Texas, USA (open access)

Habitat Quantity of Red-Cockaded Woodpecker Picoides Borealis (Aves: Piciformes: Picidae) in its Former Historic Landscape Near the Big Thicket Naitonal Preserve, Texas, USA

This article quantifies pine-forested habitat suitable for Red-cockaded Woodpecker in the former historic range of the species to assess the potential for possible re-colonization.
Date: January 26, 2016
Creator: Thapa, Vivek & Acevedo, Miguel F.
System: The UNT Digital Library
Sedentary Behaviors and Obesity in a Low-Income, Ethnic-Minority Population (open access)

Sedentary Behaviors and Obesity in a Low-Income, Ethnic-Minority Population

This article examines sedentary pastimes specifically in low-income, minority communities in the United States.
Date: January 2013
Creator: Shuval, Kerem; Leonard, Tammy; Murdoch, James; O'Brien Caughy, Margaret; Kohl, Harold W. & Sugg Skinner, Celette
System: The UNT Digital Library
Colorado State University Solar Heated and Cooled House (open access)

Colorado State University Solar Heated and Cooled House

None
Date: January 1, 1974
Creator: Lof, G.O.G.
System: The UNT Digital Library
Elements of high constructive deltaic sedimentation, lower Frio Formation, Brazoria County, Texas (open access)

Elements of high constructive deltaic sedimentation, lower Frio Formation, Brazoria County, Texas

The lower Frio Formation in eastern Brazoria County, upper Texas Gulf Coast, was deposited in a high constructive deltaic environment in the Houston delta system. Constructive elements of the stacked, elongate to lobate deltas that were intersected in core are storm induced delta front splays, delta front slump deposits, and distributary mouth bar, distributary channel and delta plain assemblages. Reworked and winnowed abandonment facies that are volumetrically insignificant relative to constructive elements are subdivided into a crossbedded shoreface-foreshore subfacies and a fine grained cyclic sequence of storm deposits on the lower shoreface that represent a distal abandonment subfacies. Micropaleontological evidence indicates that deposition of constructive and abandonment facies took place in water depths of less than 120 feet.
Date: January 1, 1982
Creator: Tyler, N. & Han, J. H.
System: The UNT Digital Library
Tritium technology programs in the United States (open access)

Tritium technology programs in the United States

Tritium technology in the United States has advanced considerably since the 1988 Tritium Conferences in Toronto. This advance has come in facilities, processing and safety related technologies and in an ever increasing commitment to compliance related issues. The major laboratories in the US tritium programs continue to be (Westinghouse) Savannah River Site, EG G Mound, Lawrence Livermore National Laboratory, Sandia National Laboratory and the Los Alamos National Laboratory. Each of these Laboratories have made some significant changes in their programs and/or facilities in the past four years. 11 refs, 1 fig.
Date: January 1, 1991
Creator: Anderson, J. L.
System: The UNT Digital Library
New Hot Laboratory Facilities at Los Alamos (open access)

New Hot Laboratory Facilities at Los Alamos

New Hot Laboratory Facilities which support three major research programs directed by the Los Alamos Scientific Laboratory of the University of California are described. For the Nuclear Rocket Propulsion Program, a hot cell addition to the Radio Chemistry Building at Los Alamos will be completed early in 1963, and construction is expected to start soon on the hot cell addition to the Maintenance, Assembly and Disassembly Building at the Nuclear Rocket Development Station in Nevada. Integral hot laboratories are designed in the facilities for the Ultra High Temperature Reactor Experiment and the Fast Reactor Core Test at Los Alamos. (auth)
Date: January 1, 1962
Creator: Wherritt, Charles R.; Franke, Paul R.; Field, R. E. & Lyle, A. R.
System: The UNT Digital Library
Clay mineralogy and depositional history of the Frio Formation in two geopressured wells, Brazoria County, Texas (open access)

Clay mineralogy and depositional history of the Frio Formation in two geopressured wells, Brazoria County, Texas

Twenty-three shale samples ranging in depth from 5194 ft to 13,246 ft from Gulf Oil Corporation No. 2 Texas State Lease 53034 well and 33 shale samples ranging in depth from 2185 ft to 15,592 ft from General Crude Oil Company/Department of Energy No. 1 Pleasant Bayou well were examined by x-ray techniques to determine the mineralogy of the geopressured zone in the Brazoria Fairway. Both wells have similar weight-percent trends with depth for a portion of the mineralogy. Calcite decreases, and plagioclase, quartz and total clay increase slightly. Within the clays, illite in mixed-layer illite/smectite (I/S) increases and smectite in mixed-layer I/S decreases. Four minerals have distinctly different trends with depth for each well. In the No. 2 Texas State Lease 53034 well, potassium feldspar and mixed-layer I/S decrease, kaolinite increases, and discrete illite is constant. In the No. 1 Pleasant Bayou well, potassium feldspar and kaolinite are constant, mixed-layer I/S increases, and discrete illite decreases.
Date: January 1, 1982
Creator: Freed, R.L.
System: The UNT Digital Library
Activated transport in AMTEC electrodes (open access)

Activated transport in AMTEC electrodes

Transport of alkali metal atoms through porous cathodes of alkali metal thermal-to-electric converter (AMTEC) cells is responsible for significant, reducible losses in the electrical performance of these cells. Experimental evidence for activated transport of metal atoms at grain surfaces and boundaries within some AMTEC electrodes has been derived from temperature dependent studies as well as from analysis of the detailed frequency dependence of ac impedance results for other electrodes, including thin, mature molybdenum electrodes which exhibit transport dominated by free molecular flow of sodium gas at low frequencies or dc conditions. Activated surface transport will almost always exist in parallel with free molecular flow transport, and the process of alkali atom adsorption/desorption from the electrode surface will invariably be part of the transport process, and possibly a dominant part in some cases. Little can be learned about the detailed mass transport process from the ac impedance or current voltage curves of an electrode at one set of operating parameters, because the transport process includes a number of important physical parameters that are not all uniquely determined by one experiment. The temperature dependence of diffusion coefficient of the alkali metal through the electrode in several cases provides an activation energy and …
Date: January 1, 1992
Creator: Williams, R.M.; Jeffries-Nakamura, B.; Ryan, M.A.; Underwood, M.L.; O'Connor, D. & Kikkert, S.
System: The UNT Digital Library

Neighborhood Price Externalities of Foreclosure Rehabilitation: An Examination of the Neighborhood Stabilization Program

This article examines the neighborhood price impacts of Neighborhood Stabilization Program (NSP) funded foreclosure rehabilitation undertaken by Habitat for Humanity in Dallas County, Texas using a difference-in-difference framework.
Date: January 12, 2017
Creator: Leonard, Tammy; Jha, Nikhil & Zhang, Lei
System: The UNT Digital Library
Deep crustal sediment study: Widespread Precambrian layered rocks (Sedimentary) beneath the US midcontinent (open access)

Deep crustal sediment study: Widespread Precambrian layered rocks (Sedimentary) beneath the US midcontinent

A thick sequence of layered rocks occurs beneath the Phanerozoic platform strata which blanket the US midcontinent. Observed on COCORP deep reflection data in southern Illinois and Indiana and in SW Oklahoma and adjacent Texas, this sequence is locally 1--3 times as thick as the overlying Paleozoic cover, but the origin of this sequence, its ultimate lateral extent, and resource potential are unknown. The objective of this project is to seek and reprocess seismic reflection data provided by industry from the US midcontinent and together with the COCORP deep reflection data and information from the scattered basement-penetrating drill holes, to begin to constrain the distribution, origin and evolution of this enigmatic layered sequence, particularly to evaluate if sedimentary material may be an important constituent (i.e., deep gas potential).
Date: January 1, 1992
Creator: Hauser, E. C.
System: The UNT Digital Library
Steady-State Thermomechanical Finite Element Analysis of Elastoviscoplastic Metal Forming Processes (open access)

Steady-State Thermomechanical Finite Element Analysis of Elastoviscoplastic Metal Forming Processes

Extrusion and rolling processes exhibiting large amounts of plastic flow are analyzed using a finite element technique that is based on a modified creeping viscous flow approximation. The technique, called the initial stress-rate method, iteratively corrects creeping viscous flow solutions to generate results that include elastic response. The momentum equations have been coupled with the energy equation to provide the capability to predict thermomechanical response during forming operations.
Date: January 1, 1977
Creator: Dawson, P.R. & Thompson, E.G.
System: The UNT Digital Library
Influence of Geometry on Natural Convection in Buildings (open access)

Influence of Geometry on Natural Convection in Buildings

Strong free convection airflows occur within passive solar buildings resulting from elevated temperatures of surfaces irradiated by solar energy compared with the cooler surfaces not receiving radiation. The geometry of a building has a large influence on the directions and magnitudes of natural airflows, and thus heat transfer between zones. This investigation has utilized a variety of reduced-scale building configurations to study the effects of geometry on natural convection heat transfer. Similarity between the reduced-scale model and a full-scale passive solar building is achieved by having similar geometries and by replacing air with Freon-12 gas as the model's working fluid. Filling the model with Freon-12 gas results in similarity in Prandtl numbers and Rayleigh numbers based on temperature differences in the range from 10/sup 9/ to 10/sup 11/. Results from four geometries are described with an emphasis placed on the effects of heat loss on zone temperature stratification shifts.
Date: January 1, 1985
Creator: White, M. D.; Winn, C. B.; Jones, G. F. & Balcomb, J. D.
System: The UNT Digital Library
Dual arm master controller development (open access)

Dual arm master controller development

The advanced servomanipulator (ASM) slave was designed with an anthropomorphic stance, gear/torque tube power drives, and modular construction. These features resulted in increased inertia, friction, and backlash relative to tape-driven manipulators. Studies were performed which addressed the human factors design and performance trade-offs associated with the corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm master controller, are presented. This work was performed as part of the Consolidated Fuel Reprocessing Program at the Oak Ridge National Laboratory. 5 refs., 7 figs., 1 tab.
Date: January 1, 1985
Creator: Kuban, D. P. & Perkins, G. S.
System: The UNT Digital Library
Low Energy X-Ray Spectra Measured With a Mercuric Iodide Energy Dispersive Spectrometer in a Scanning Electron Microscope (open access)

Low Energy X-Ray Spectra Measured With a Mercuric Iodide Energy Dispersive Spectrometer in a Scanning Electron Microscope

A mercuric iodide energy dispersive x-ray spectrometer, with Peltier cooling provided for the detector and input field effect transistor, has been developed and tested in a scanning electron microscope. X-ray spectra were obtained with the 15 keV electron beam. An energy resolution of 225 eV (FWHM) for Mn-K/sub ..cap alpha../ at 5.9 keV and 195 eV (FWHM) for Mg-K line at 1.25 keV has been measured. Overall system noise level was 175 eV (FWHM). The detector system characterization with a carbon target demonstrated good energy sensitivity at low energies and lack of significant spectral artifacts at higher energies. 16 refs., 5 figs.
Date: January 1, 1985
Creator: Iwanczyk, J. S.; Dabrowski, A. J.; Huth, G. C.; Bradley, J. G.; Conley, J. M. & Albee, A. L.
System: The UNT Digital Library
Refractory materials for high-temperature thermoelectric energy conversion (open access)

Refractory materials for high-temperature thermoelectric energy conversion

Theoretical work of two decades ago adequately explained the transport behavior and effectively guided the development of thermoelectric materials of high conversion efficiencies of conventional semiconductors (e.g., SiGe alloys). The more significant contributions involved the estimation of optimum doping concentrations, the reduction of thermal conductivity by solid solution doping and the development of a variety of materials with ZT approx. 1 in the temperature range 300 K to 1200 K. It was also shown that ZT approx. 1 is not a theoretical limitation although, experimentally, values in excess of one were not achieved. Work has continued with emphasis on higher temperature energy conversion. A number of promising materials have been discovered in which it appears that ZT > 1 is realizable. These materials can be divided into two classes: (i) the rare-earth chalcogenides, which behave as itinerant highly-degenerate n-type semiconductors at room-temperature, and (ii) the boron-rich borides, which exhibit p-type small-polaronic hopping conductivity.
Date: January 1, 1983
Creator: Wood, C. & Emin, D.
System: The UNT Digital Library
Comparative Performance of Two Types of Evacuated Tube Solar Collectors in a Residential Heating and Cooling System - The Progress Report (open access)

Comparative Performance of Two Types of Evacuated Tube Solar Collectors in a Residential Heating and Cooling System - The Progress Report

Two types of evacuated tube solar collectors have been operated in space heating, cooling and domestic hot water heating systems in Colorado State University Solar House I. An experimental collector from Corning Glass Works supplied heat to the system from January 1977 through February 1978, and an experimental collector from Philips Research Laboratory, Aachen, which is currently in use, has been operating since August 1978. A flat absorber plate inside a single-walled glass tube is used in the Corning design, whereas heat is conducted through a single glass wall to an external heat exchanger plate in the Philips collector. In comparison with conventional flat-plate collectors, both types show reduced heat losses and improved efficiency. For space heating and hot water supply in winter, the solar delivery efficiency of the Corning collector ranged from 49% to 60% of the incident solar energy. The portion of the space heating and domestic hot water load carried by solar energy through fall and winter ranged from 50% to 74%, with a four-month contribution of 61% of the total requirements. Data on the Philips collector are currently being analyzed.
Date: January 1, 1979
Creator: Conway, T. M.; Duff, W. S.; Loef, G. O. G. & Pratt, R. G.
System: The UNT Digital Library
Semiconductor processing with excimer lasers (open access)

Semiconductor processing with excimer lasers

The advantages of pulsed excimer lasers for semiconductor processing are reviewed. Extensive comparisons of the quality of annealing of ion-implanted Si obtained with XeCl and ruby lasers have been made. The results indicate that irrespective of the large differences in the optical properties of Si at uv and visible wavelengths, the efficiency of usage of the incident energy for annealing is comparable for the two lasers. However, because of the excellent optical beam quality, the XeCl laser can provide superior control of the surface melting and the resulting junction depth. Furthermore, the concentrations of electrically active point defects in the XeCl laser annealed region are 2 to 3 orders of magnitude lower than that obtained from ruby or Nd:YAG lasers. All these results seem to suggest that XeCl lasers should be suitable for fabricating not only solar cells but also the more advanced device structures required for VLSI or VHSIC applications.
Date: January 1, 1983
Creator: Young, R.T.; Narayan, J.; Christie, W.H.; van der Leeden, G.A.; Rothe, D.E. & Cheng, L.J.
System: The UNT Digital Library
Neutral sheet crossings in the distant magnetotail (open access)

Neutral sheet crossings in the distant magnetotail

We have analyzed the magnetic field data from ISEE-3 in the distant magnetotail for 18 crossings of the cross-tail current sheet (or so-called natural sheet) to determine the direction of the normal component B/sub z/. The crossings occurred near the middle of the aberrated magnetotail (0 < y < 30 R/sub e, -10 < z < 5) in GSM coordinates, at a distance of about 220 R/sub e/, January 28 to February 12, 1983; in each case the plasma flow velocity was tailward. In 2 cases we found B/sub z/ negative (southward), as would be required with a magnetic neutral line (reconnection line) earthward of the spacecraft. In 12 cases B/sub z/ was clearly northward (B/sub z/ > 0.4 nT), consistent with closed field lines connected to the earth. In 3 cases B/sub z/ was very close to zero; in several instances there was structure in B/sub y/, suggesting localized currents with x or z directions. One may have been a magnetopause crossing. The strong preponderance of northward B/sub z/ favors a model of the magnetotail which is dominated by boundary layer plasma, flowing tailward on closed magnetic field lines, which requires the existence of an electric field in the …
Date: January 1, 1985
Creator: Heikkila, W. J.; Slavin, J. A.; Smith, E. J.; Baker, D. N. & Zwickl, R. D.
System: The UNT Digital Library