The CDF TESTCLK module - Providing system level clocking and triggering for Run 2 prototyping crates (open access)

The CDF TESTCLK module - Providing system level clocking and triggering for Run 2 prototyping crates

The TESTCLK module was specifically designed for use in prototyping crates for the Colliding Detector Facility (CDF) Run 2 Experiment at Fermi National Accelerator Laboratory. The TESTCLK Module allows the user to supply system clocks and trigger signals to stand-alone crates. This module has allowed designers of the CDF Run 2 electronics to thoroughly test their modules, despite the lack of a DAQ system supplied clock and trigger interface. This paper will explore the features that were found important to incorporate into the TESTCLK, and describe how they were implemented. The paper will also describe how the TESTCLK module has been used to support the initial implementation of the DAQ system at CDF. This has allowed data taking and testing of CDF Electronic modules before production clock and trigger modules became available.
Date: November 5, 1999
Creator: Stuermer, Theresa Shaw and Walter
Object Type: Article
System: The UNT Digital Library
Procedures for addressing uncertainty and variability in exposure to characterize potential health risk from trichloroethylene contaminated ground water at Beale Air Force Base in California (open access)

Procedures for addressing uncertainty and variability in exposure to characterize potential health risk from trichloroethylene contaminated ground water at Beale Air Force Base in California

Conservative deterministic, screening-level calculations of exposure and risk commonly are used in quantitative assessments of potential human-health consequences from contaminants in environmental media. However, these calculations generally are based on multiple upper-bound point estimates of input parameters, particularly for exposure attributes, and can therefore produce results for decision makers that actually overstate the need for costly remediation. Alternatively, a more informative and quantitative characterization of health risk can be obtained by quantifying uncertainty and variability in exposure. This process is illustrated in this report for a hypothetical population at a specific site at Beale Air Force Base in California, where there is trichloroethylene (TCE) contaminated ground water and a potential for future residential use. When uncertainty and variability in exposure were addressed jointly for this case, the 95th-percentile upper-bound value of individual excess lifetime cancer risk was a factor approaching 10 lower than the most conservative deterministic estimate. Additionally, the probability of more than zero additional cases of cancer can be estimated, and in this case it is less than 0.5 for a hypothetical future residential population of up to 26,900 individuals present for any 7.6-y interval of a 70-y time period. Clearly, the results from application of this probabilistic …
Date: October 5, 1999
Creator: Daniels, J I; Bogen, K T & Hall, L C
Object Type: Report
System: The UNT Digital Library
Establishment of Harrop, High-Temperature Viscometer (open access)

Establishment of Harrop, High-Temperature Viscometer

This report explains how the Harrop, High-Temperature Viscometer was installed, calibrated, and operated. This report includes assembly and alignment of the furnace, viscometer, and spindle, and explains the operation of the Brookfield Viscometer, the Harrop furnace, and the UDC furnace controller. Calibration data and the development of the spindle constant from NIST standard reference glasses is presented. A simple operational procedure is included.
Date: November 5, 1999
Creator: Schumacher, R. F.
Object Type: Report
System: The UNT Digital Library
Flash photolysis-shock tube studies. (open access)

Flash photolysis-shock tube studies.

Following earlier investigations on the dissociation rates of halogen containing molecules, we studied the thermal decompositions of CHCl{sub 3} and CF{sub 3}Br. In addition, we measured the branching ratio and rate constants for the thermal decomposition of H{sub 2}CO. We studied three bimolecular rate processes: H + H{sub 2}CC0, CF{sub 3} + H{sub 2}, and H + CF{sub 3}H. Decomposition studies in reflected shock waves on three reactions were completed using atomic resonance absorption spectroscopic (ARAS) detection and/or the laser schlieren density gradient (LS) method.
Date: March 5, 1998
Creator: Michael, J. V.
Object Type: Article
System: The UNT Digital Library
Dynamics of the Inflationary Era (open access)

Dynamics of the Inflationary Era

There is very strong circumstantial evidence that there was an inflationary epoch very early in the history of the universe. In this lecture the author describes how we might be able to piece together some understanding of the dynamics during and immediately after the inflationary epoch.
Date: November 5, 1999
Creator: Kolb, Edward W.
Object Type: Article
System: The UNT Digital Library
Laser Engineered Net Shaping (LENS(TM)): A Tool for Direct Fabrication of Metal Parts (open access)

Laser Engineered Net Shaping (LENS(TM)): A Tool for Direct Fabrication of Metal Parts

For many years, Sandia National Laboratories has been involved in the development and application of rapid prototyping and dmect fabrication technologies to build prototype parts and patterns for investment casting. Sandia is currently developing a process called Laser Engineered Net Shaping (LENS~) to fabricate filly dense metal parts dwectly from computer-aided design (CAD) solid models. The process is similar to traditional laser-initiated rapid prototyping technologies such as stereolithography and selective laser sintering in that layer additive techniques are used to fabricate physical parts directly from CAD data. By using the coordinated delivery of metal particles into a focused laser beam apart is generated. The laser beam creates a molten pool of metal on a substrate into which powder is injected. Concurrently, the substrate on which the deposition is occurring is moved under the beam/powder interaction zone to fabricate the desired cross-sectiwal geometry. Consecutive layers are additively deposited, thereby producing a three-dmensional part. This process exhibits enormous potential to revolutionize the way in which metal parts, such as complex prototypes, tooling, and small-lot production parts, are produced. The result is a comple~ filly dense, near-net-shape part. Parts have been fabricated from 316 stainless steel, nickel-based alloys, H13 tool steel, and titanium. …
Date: November 5, 1998
Creator: Atwood, C.; Ensz, M.; Greene, D.; Griffith, M.; Harwell, L.; Reckaway, D. et al.
Object Type: Article
System: The UNT Digital Library
Single top production and top properties at the Tevatron (open access)

Single top production and top properties at the Tevatron

We summarize recent measurements made at the Tevatron Collider using top event candidates. Cross section and mass measurements are discussed in a separate contribution to these Proceedings. Here we report on studies of the top P<sub>T</sub> distribution in t{anti t} production and studies of single top production. Properties of top decays examined are: BF(t {yields} Wb)/BF(t {yields} Wq), helicity amplitudes of W's from top decays and correlations of t{anti t} decay products. Searches for new physics in rare top decays and a search for a state X {yields} t{anti t} are also reported.
Date: November 5, 1999
Creator: Barbaro-Galtieri, Angela
Object Type: Article
System: The UNT Digital Library
Preliminary modeling of moisture movement in the tuff beneath Mortandad Canyon, Los Alamos National Laboratory (open access)

Preliminary modeling of moisture movement in the tuff beneath Mortandad Canyon, Los Alamos National Laboratory

An area of upper/middle Mortandad Canyon on the Los Alamos National Laboratory is modeled in cross-section. UNSAT2, a finite element model (FEM) is used to predict moisture movement. Hydraulic characteristics of the tuff are described by van Genuchten parameters determined from laboratory tests on cores taken from a borehole within the cross-section. Material properties are distributed horizontal planar in space to cover the solution domain with required initial conditions. An estimate of seepage flux from a thin perched alluvial aquifer into the upper surface of the tuff is taken from a lumped parameter model. Moisture redistribution for a ponded boundary condition and a larger flux is investigated. A composite simulation using material properties from two separate coreholes is also evaluated.
Date: August 5, 1992
Creator: Geddis, A.M.
Object Type: Report
System: The UNT Digital Library
Understanding Thermal Behavior in Lens Processing of Structural Materials (open access)

Understanding Thermal Behavior in Lens Processing of Structural Materials

In direct laser metal deposition technologies, such as the Laser (LENS) process, it is important to understand and control the Engineered Net Shaping thermal behavior during fabrication. With this control, components can be reliably fabricated with desired structural material properties. This talk will describe the use of contact and imaging techniques to monitor the thermal signature during LENS processing. Recent results show a direct correlation between thermal history and material properties, where the residual stress magnitude decreases as the laser power, and therefore thermal signature, increases. Development of an understanding of solidification behavior, residual stress, and microstructural evolution with respect to thermal behavior will be discussed.
Date: November 5, 1998
Creator: Ensz, M. T.; Greene, D. L.; Griffith, M. L.; Harwell, L. D.; Hofmeister, W. H.; Nelson, D. V. et al.
Object Type: Article
System: The UNT Digital Library
Summary of the Exploratory Studies Facility Alternatives Study; Draft (open access)

Summary of the Exploratory Studies Facility Alternatives Study; Draft

This paper presents a summary of the conduct and findings of the Exploratory Studies Facility Alternatives Study (ESF-AS). The Exploratory Studies Facility (ESF) is being planned for use in the characterization of a site for a potential high-level nuclear waste repository at Yucca Mountain, NV. The purpose of the ESF-AS were to identify and rank order ESF-repository options and to improve understanding of the favorable or unfavorable features of the ESF design. The analysis resulted in the ranking of 34 options, in accordance with the extent to which each option could achieve the objectives. Additional findings regarding design features that were identified as key elements in an option`s ability to provide good overall performance are also discussed.
Date: December 5, 1991
Creator: Costin, L.S.; Dennis, A.W. & Stevens, A.L.
Object Type: Article
System: The UNT Digital Library
Application of geometry correction factors for low-level waste package dose measurements. Revision 1 (open access)

Application of geometry correction factors for low-level waste package dose measurements. Revision 1

Plans are to determine the Cs-137 content of low-level waste packages generated in High-Level Waste by measuring the radiation level at a specified distance from the package with a hand-held radiation instrument. The measurement taken at this specified distance, either 3 or 5 feet, is called the far-field measurement. This report documents a method for adjusting the gamma exposure rate (mR/hr) reading used in dose-to-curie determinations when the far-field measurement equals the background reading. This adjustment is necessary to reduce the conservatism resulting from using a minimum detection limit exposure rate for the dose-to-curie determination for the far-field measurement position. To accomplish this adjustment, the near-field (5 cm) measurement is multiplied by a geometry correction factor to obtain an estimate of the far field exposure rate (which is below instrument sensitivity). This estimate of the far field exposure rate is used to estimate the Cs-137 curie content of the package. This report establishes the geometry correction factors for the dose-to-curie determination when the far-field gamma exposure measurement equals the background reading. This report also provides a means of demonstrating compliance to 1S Manual requirements for exposure rate readings at different locations from waste packages while specifying only two measurement positions. …
Date: January 5, 1995
Creator: Chandler, M.C. & Parish, B.
Object Type: Report
System: The UNT Digital Library
Laser ablation of concrete. (open access)

Laser ablation of concrete.

Laser ablation is effective both as an analytical tool and as a means of removing surface coatings. The elemental composition of surfaces can be determined by either mass spectrometry or atomic emission spectroscopy of the atomized effluent. Paint can be removed from aircraft without damage to the underlying aluminum substrate, and environmentally damaged buildings and sculptures can be restored by ablating away deposited grime. A recent application of laser ablation is the removal of radioactive contaminants from the surface and near-surface regions of concrete. We present the results of ablation tests on concrete samples using a high power pulsed Nd:YAG laser with fiber optic beam delivery. The laser-surface interaction was studied on various model systems consisting of Type I Portland cement with varying amounts of either fine silica or sand in an effort to understand the effect of substrate composition on ablation rates and mechanisms. A sample of non-contaminated concrete from a nuclear power plant was also studied. In addition, cement and concrete samples were doped with non-radioactive isotopes of elements representative of cooling waterspills, such as cesium and strontium, and analyzed by laser-resorption mass spectrometry to determine the contamination pathways. These samples were also ablated at high power to …
Date: October 5, 1998
Creator: Savina, M.
Object Type: Article
System: The UNT Digital Library
Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures (open access)

Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures

This project attempts to demonstrate the effectivensss of exploiting thin-layered, low energy deposits at the distal margin of a propagating turbinite complex through u se of hydraulically fractgured horizontal of high-angle wells. TGhe combinaton of a horizontal or high-angle weoo and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore.
Date: February 5, 1998
Creator: Laue, Mike L.
Object Type: Report
System: The UNT Digital Library
Fast Multipole Solvers for Three-Dimensional Radiation and Fluid Flow Problems (open access)

Fast Multipole Solvers for Three-Dimensional Radiation and Fluid Flow Problems

A number of physics problems can be modeled by a set of N elements, which have pair-wise interactions with one another. The use of such elements for the evolution of vorticity in fluid flows and the calculation of the velocity field from the evolving vorticity field is well known. Fast multipole methods for fluid flow problems have been developed in we pmt to reduce computational effort to something less than O(N) . In this paper we develop a fast multipole solver with application to both 3-D radiation problems (calculation of the heat flux from the evolving temperature field in an absorbing medium) and 3-D fluid flow. This is accomplished by using a more general kernel for the associated volume integrals. This kernel also encompasses other applications such as gravitational fields, electrostatics, scattering, etc. The present algorithm has been designed to have a very high "parallel efficiency" when used on massively parallel computers. This feature comes at the expense of computational effort, which is less than O(N) but greater than O(N) or O(MnN).
Date: November 5, 1998
Creator: Baty, R. S.; Burns, S. P.; Gritzo, L. A.; Homicz, G. F. & Strickland, J. H.
Object Type: Article
System: The UNT Digital Library
Predicting tropospheric ozone and hydroxyl radical in a global, three-dimensional, chemistry, transport, and deposition model (open access)

Predicting tropospheric ozone and hydroxyl radical in a global, three-dimensional, chemistry, transport, and deposition model

Two of the most important chemically reactive tropospheric gases are ozone (O{sub 3}) and the hydroxyl radical (OH). Although ozone in the stratosphere is a necessary protector against the sun`s radiation, tropospheric ozone is actually a pollutant which damages materials and vegetation, acts as a respiratory irritant, and is a greenhouse gas. One of the two main sources of ozone in the troposphere is photochemical production. The photochemistry is initiated when hydrocarbons and carbon monoxide (CO) react with nitrogen oxides (NO{sub x} = NO + NO{sub 2}) in the presence of sunlight. Reaction with the hydroxyl radical, OH, is the main sink for many tropospheric gases. The hydroxyl radical is highly reactive and has a lifetime on the order of seconds. Its formation is initiated by the photolysis of tropospheric ozone. Tropospheric chemistry involves a complex, non-linear set of chemical reactions between atmospheric species that vary substantially in time and space. To model these and other species on a global scale requires the use of a global, three-dimensional chemistry, transport, and deposition (CTD) model. In this work, I developed two such three dimensional CTD models. The first model incorporated the chemistry necessary to model tropospheric ozone production from the reactions …
Date: January 5, 1995
Creator: Atherton, C.S.
Object Type: Report
System: The UNT Digital Library
LiMn{sub 2-x}Cu{sub x}O{sub 4} spinels (0.1 {le} x {le} 0.5) - a new class of 5 V cathode materials for Li batteries : I. electrochemical, structural and spectroscopic studies. (open access)

LiMn{sub 2-x}Cu{sub x}O{sub 4} spinels (0.1 {le} x {le} 0.5) - a new class of 5 V cathode materials for Li batteries : I. electrochemical, structural and spectroscopic studies.

A series of electroactive spinel compounds, LiMn{sub 2{minus}x}Cu{sub x}O{sub 4} (0.1 {le} x {le} 0.5) has been studied by crystallographic, spectroscopic and electrochemical methods and by electron-microscopy. These LiMn{sub 2{minus}x}Cu{sub x}O{sub 4} spinels are nearly identical in structure to cubic LiMn{sub 2}O{sub 4} and successfully undergo reversible Li intercalation. The electrochemical data show a remarkable reversible electrochemical process at 4.9 V which is attributed to the oxidation of Cu{sup 2+} to Cu{sub 3+}. The inclusion of Cu in the spinel structure enhances the electrochemical stability of these materials upon cycling. The initial capacity of LiMn{sub 2{minus}x}Cu{sub x}O{sub 4} spinels decreases with increasing x from 130mAh/g in LiMn{sub 2}O{sub 4} (x=0) to 70 mAh/g in ''LiMn{sub 1.5}Cu{sub 0.5}O{sub 4}'' (x=0.5). The data also show slight shifts to higher voltage for the delithiation reaction that normally occurs at 4.1 V in standard Li{sub 1{minus}x}Mn{sub 2}O{sub 4} electrodes (1 {ge} x {ge} 0) corresponding to the oxidation of Mn{sup 3+} to Mn{sup 4+}. Although the powder X-ray diffraction pattern of ''LiMn{sub 1.5}Cu{sub 0.5}O{sub 4}'' shows a single-phase spinel product, neutron diffraction data show a small, but significant quantity of an impurity phase, the composition and structure of which could not be identified. X-ray …
Date: October 5, 1998
Creator: Ein-Eli, Y.
Object Type: Article
System: The UNT Digital Library
Observations of Non-Close-Packed Arrangements in Multilayers of Passivated Gold Clusters (open access)

Observations of Non-Close-Packed Arrangements in Multilayers of Passivated Gold Clusters

The stacking of second and third layers of supercrystals of self-assembled passivated gold nanoparticles has been investigated using transmission electron microscopy. We report for the first time nanoparticles occupying the twofold saddle site in the third layer.
Date: October 5, 1999
Creator: AINDOW, M.; Brown, P.; Kiely, C. J.; Wellner, A. & Wilcoxon, Jess P.
Object Type: Article
System: The UNT Digital Library
Signals from Microwave Unstable Beams in the SLC Damping Rings (open access)

Signals from Microwave Unstable Beams in the SLC Damping Rings

The longitudinal microwave instability is present in the SLC damping rings during routine operations. Experimental studies of the instability at nominal conditions have been reported previously. To complement those studies and better understand the properties of the instability a series of dedicated experiments were performed under a broad range of operating parameters. These experiments included spectral measurements of BPM signals as well as time domain diagnostics using a custom detecting circuit. This paper describes the techniques, the results and discusses possible interpretations of these measurements.
Date: April 5, 1999
Creator: Podobedev, Boris
Object Type: Report
System: The UNT Digital Library
Clean energy from municipal solid waste. Technical progress report number 3 (open access)

Clean energy from municipal solid waste. Technical progress report number 3

Development of the computer models for slurry carbonization have begun and were based upon the collected data (mass balances, yield, temperatures, and pressures) from the previous pilot plant campaigns. All computer models are being developed with Aspen`s SpeedUp{trademark} software. The primary flow sheet with major alternatives has been developed and the majority of equipment descriptions and models, cost algorithms, and baseline parameters have been input to SpeedUp. The remaining modeling parameters will be input in the next reporting period and the initial flow sheet skeleton and model will be completed. The computer models will focus on optimizing capital and operating costs, and evaluating alternative waste water recycling technologies. The weaknesses of the previous pilot plant data and the data required for design of the commercial demonstration facility were identified. The identified weaknesses of the existing data included mass balance precision and accuracy, reactor residence time control (i.e. reactor level control), reactor temperature variations, and air entrainment in the feed RDF slurry. To improve mass balance precision and accuracy, an alternative carbonization gas flow meter will be designed and installed on the pilot plant. EnerTech`s carbonization gas flow meter design has been submitted to the EERC for final approval. In addition, …
Date: January 5, 1996
Creator: Klosky, M.
Object Type: Report
System: The UNT Digital Library
The human DNA-activated protein kinase, DNA-PK: Substrate specificity (open access)

The human DNA-activated protein kinase, DNA-PK: Substrate specificity

Although much has been learned about the structure and function of p53 and the probable sequence of subsequent events that lead to cell cycle arrest, little is known about how DNA damage is detected and the nature of the signal that is generated by DNA damage. Circumstantial evidence suggests that protein kinases may be involved. In vitro, human DNA-PK phosphorylates a variety of nuclear DNA-binding, regulatory proteins including the tumor suppressor protein p53, the single-stranded DNA binding protein RPA, the heat shock protein hsp90, the large tumor antigen (TAg) of simian virus 40, a variety of transcription factors including Fos, Jun, serum response factor (SRF), Myc, Sp1, Oct-1, TFIID, E2F, the estrogen receptor, and the large subunit of RNA polymerase II (reviewed in Anderson, 1993; Jackson et al., 1993). However, for most of these proteins, the sites that are phosphorylated by DNA-PK are not known. To determine if the sites that were phosphorylated in vitro also were phosphorylated in vivo and if DNA-PK recognized a preferred protein sequence, the authors identified the sites phosphorylated by DNA-PK in several substrates by direct protein sequence analysis. Each phosphorylated serine or threonine is followed immediately by glutamine in the polypeptide chain; at no …
Date: November 5, 1994
Creator: Anderson, C.W.; Connelly, M.A.; Zhang, H.; Sipley, J.A.; Lees-Miller, S.P.; Lintott, L.G. et al.
Object Type: Report
System: The UNT Digital Library
Risk assessment of nonhazardous oil-field waste disposal in salt caverns. (open access)

Risk assessment of nonhazardous oil-field waste disposal in salt caverns.

In 1996, Argonne National Laboratory (ANL) conducted a preliminary technical and legal evaluation of disposing of nonhazardous oil-field wastes (NOW) into salt caverns. Argonne determined that if caverns are sited and designed well, operated carefully, closed properly, and monitored routinely, they could be suitable for disposing of oil-field wastes. On the basis of these findings, Argonne subsequently conducted a preliminary evaluation of the possibility that adverse human health effects (carcinogenic and noncarcinogenic) could result from exposure to contaminants released from the NOW disposed of in domal salt caverns. Steps used in this evaluation included the following: identifying potential contaminants of concern, determining how humans could be exposed to these contaminants, assessing contaminant toxicities, estimating contaminant intakes, and calculating human cancer and noncancer risk estimates. Five postclosure cavern release scenarios were assessed. These were inadvertent cavern intrusion, failure of the cavern seal, failure of the cavern through cracks, failure of the cavern through leaky interbeds, and a partial collapse of the cavern roof. Assuming a single, generic, salt cavern and generic oil-field wastes, potential human health effects associated with constituent hazardous substances (arsenic, benzene, cadmium, and chromium) were assessed under each of these scenarios. Preliminary results provided excess cancer risk and …
Date: March 5, 1998
Creator: Elcock, D.
Object Type: Article
System: The UNT Digital Library
The quandry of benchmarking broadcasts (open access)

The quandry of benchmarking broadcasts

A message passing library's implementation of broadcast communication can significantly affect the performance of applications built with that library. In order to choose between similar implementations or to evaluate available libraries, accurate measurements of broadcast performance are required. As we demonstrate, existing methods for measuring broadcast performance are either inaccurate or inadequate. Fortunately, we have designed an accurate method for measuring broadcast performance. Measuring broadcast performance is not simple. Simply sending one broadcast after another allows them to proceed through the network concurrently, thus resulting in accurate per broadcast timings. Existing methods either fail to eliminate this pipelining effect or eliminate it by introducing overheads that are as difficult to measure as the performance of the broadcast itself. Our method introduces a measurable overhead to eliminate the pipelining effect.
Date: February 5, 1999
Creator: Karonis, N T & Supinski, B R
Object Type: Article
System: The UNT Digital Library
Diffusion in phase space (open access)

Diffusion in phase space

In order to study diffusion in any region of phase space containing nested closed curves we choose action-angle variables, {gamma}, J. the action J labels each closed phase curve and is equal to its area divided by 2{pi}. We can introduce rectangular variables Q,P by the equations Q=(2J){sup 1/2}sin{gamma}, P=(2J){sup 1/2}cos{gamma}, where the angle variable {gamma} is measured clockwise from the P-axis. The phase curves are circles in the Q,P plane with radius (2J){sup 1/2}. We assume that the motion consists of a Hamiltonian motion along a curve of fixed J (in the original coordinate system and in the system Q,P) plus a diffusion and a damping which can change the value of J. Now consider a system of particles described by a density {rho}(J,t), so that the number of particles between the curves J and J+dJ is dN={rho}(J,t)dJ. These cN particles are distributed uniformly in the phase space between the curves J and J+dJ.
Date: April 5, 1993
Creator: Symon, K.
Object Type: Report
System: The UNT Digital Library
Diurnal evapotranspiration estimates in the Walnut River Watershed. (open access)

Diurnal evapotranspiration estimates in the Walnut River Watershed.

Evapotranspiration is an essential component of the surface hydrological balance, but obtaining accurate estimates of the water vapor flux over large terrestrial areas can be difficult because of the substantial temporal and spatial variability in surface moisture conditions that can occur. This variability is often very large in the Great Plains and other portions of the Mississippi River Basin. Nevertheless, variations in soil moisture content, groundwater levels, and runoff in streams and rivers cannot be fully assessed without some knowledge of evapotranspiration rates. Here, observations made at the Walnut River Watershed (WRW), which is near Wichita, Kansas, and has an area of approximately 5000 km{sup 2}, are used to improve and test a modeling system that estimates long-term evapotranspiration with use of satellite remote sensing data with limited surface measurements. The techniques may be applied to much larger areas. As is shown in Fig. 1, the WRW is located in the Red River Basin and is enclosed by the southern Great Plains Clouds and Radiation Testbed (CART) of the US Department of Energy's Atmospheric Radiation Measurement (ARM) program. The functional relationships involving the satellite data, surface parameters, and associated subgrid-scale fluxes are modeled in this study by the parameterization of …
Date: October 5, 1998
Creator: Song, J.
Object Type: Article
System: The UNT Digital Library