Final report for 105-N Basin sediment disposition task, phase 2 -- samples BOMPC8 and BOMPC9 (open access)

Final report for 105-N Basin sediment disposition task, phase 2 -- samples BOMPC8 and BOMPC9

This document is the final report deliverable for Phase 2 analytical work for the 105-N Basin Sediment Disposition Task. On December 23, 1997, ten samples were received at the 222-S Laboratory as follows: two (2) bottles of potable water, six (6) samples for process control testing and two (2) samples for characterization. Analyses were performed in accordance with the Letter of Instruction for Phase 2 Analytical Work for the 105-N Basin Sediment Disposition Task (Logan and Kessner, 1997) (Attachment 7) and 105-N Basin Sediment Disposition Phase-Two Sampling and Analysis Plan (SAP) (Smith, 1997). The analytical results are included in Table 1. This document provides the values of X/Qs for the onsite and offsite receptors, taking into account the building wake and the atmospheric stability effects. X/Qs values for the potential fire accident were also calculated. In addition, the unit dose were calculated for the mixtures of isotopes.
Date: February 5, 1998
Creator: Esch, R. A.
Object Type: Report
System: The UNT Digital Library
Tank 241-AX-103, cores 212 and 214 analytical results for the final report (open access)

Tank 241-AX-103, cores 212 and 214 analytical results for the final report

This document is the analytical laboratory report for tank 241-AX-103 push mode core segments collected between July 30, 1997 and August 11, 1997. The segments were subsampled and analyzed in accordance with the Tank 241-AX-103 Push Mode Core Sampling and Analysis Plan (TSAP) (Comer, 1997), the Safety Screening Data Quality Objective (DQO) (Dukelow, et al., 1995) and the Data Quality Objective to Support Resolution of the Organic Complexant Safety Issue (Organic DQO) (Turner, et al., 1995). The analytical results are included in the data summary table (Table 1). None of the samples submitted for Differential Scanning Calorimetry (DSC), Total Alpha Activity (AT), plutonium 239 (Pu239), and Total Organic Carbon (TOC) exceeded notification limits as stated in the TSAP (Conner, 1997). The statistical results of the 95% confidence interval on the mean calculations are provided by the Tank Waste Remediation Systems Technical Basis Group in accordance with the Memorandum of Understanding (Schreiber, 1997) and not considered in this report.
Date: February 5, 1998
Creator: Steen, F. H.
Object Type: Report
System: The UNT Digital Library
Hanford Tanks Initiative fiscal year 1997 retrieval technology demonstrations (open access)

Hanford Tanks Initiative fiscal year 1997 retrieval technology demonstrations

The Hanford Tanks Initiative was established in 1996 to address a range of retrieval and closure issues associated with radioactive and hazardous waste stored in Hanford`s single shell tanks (SSTs). One of HTI`s retrieval goals is to ``Successfully demonstrate technology(s) that provide expanded capabilities beyond past practice sluicing and are extensible to retrieve waste from other SSTS.`` Specifically, HTI is to address ``Alternative technologies to past practice sluicing`` ... that can ... ``successfully remove the hard heel from a sluiced tank or to remove waste from a leaking SST`` (HTI Mission Analysis). During fiscal year 1997, the project contracted with seven commercial vendor teams to demonstrate retrieval technologies using waste simulants. These tests were conducted in two series: three integrated tests (IT) were completed in January 1997, and four more comprehensive Alternative Technology Retrieval Demonstrations (ARTD) were completed in July 1997. The goal of this testing was to address issues to minimize the risk, uncertainties, and ultimately the overall cost of removing waste from the SSTS. Retrieval technologies can be separated into three tracks based on how the tools would be deployed in the tank: globally (e.g., sluicing) or using vehicles or robotic manipulators. Accordingly, the HTI tests included an …
Date: February 5, 1998
Creator: Berglin, E. J.
Object Type: Report
System: The UNT Digital Library
327 legacy waste processing plan (open access)

327 legacy waste processing plan

The B and W Hanford Company`s (BWHC) 327 Facility [Postirradiation Testing Laboratory (PTL)] houses 10 hot cells in which a variety of postirradiation examinations have been performed since its construction in the mid 1950s. Over the years, the waste that was generated in these cells has been collected in one gallon buckets. These buckets are essentially one gallon cylindrical cans made of thin wall stainless steel with welded bottoms and slip fit lids. They contain assorted compactable waste (i.e., Wipe-Alls, Q-tips, towels, etc.) as well as non-compactable waste (i.e., small tools, pieces of metal tubing, etc.). There is a FY-98 BWHC Performance Agreement (PA) milestone in place to package 200 of these buckets in drums and ship them from the 327 facility to the Central Waste Complex (CWC) by September 30, 1998.
Date: May 5, 1998
Creator: Henderson, J. F.
Object Type: Report
System: The UNT Digital Library
Matrix Description of Intersecting M5 Branes (open access)

Matrix Description of Intersecting M5 Branes

Novel 3+1 dimensional N = 2 superconformal field theories (with tensionless BPS string solitons) are believed to arise when two sets of M5 branes intersect over a 3+1 dimensional hyperplane. We derive a DLCQ description of these theories as supersymmetric quantum mechanics on the Higgs branch of suitable 4d N = 1 supersymmetric gauge theories. Our formulation allows us to determine the scaling dimensions of certain chiral primary operators in the conformal field theories. We also discuss general criteria for quantum mechanical DLCQ descriptions of supersymmetric field theories (and the resulting multiplicities and scaling dimensions of chiral primary operators).
Date: March 5, 1998
Creator: Kachru, Shamit; Oz, Yaron & Yin, Zheng
Object Type: Article
System: The UNT Digital Library
MSET modeling of Crystal River-3 venturi flow meters. (open access)

MSET modeling of Crystal River-3 venturi flow meters.

The analysis of archived Crystal River-3 feedwater flow data reveals a slow and steady degradation of the flow meter measurements during the 1992/1993 operating cycle. MSET can reliably estimate the true flow rate and quantify the degree of departure between the indicated signal and the true flow rate with high accuracy. The MSET computed flow rate could, in principle, be used to provide an improved estimate of the reactor power and hence avoid the revenue loss associated with derating the reactor based on a faulty feedwater flow rate indication.
Date: January 5, 1998
Creator: Bockhorst, F. K.; Gross, K. C.; Herzog, J. P. & Wegerich, S. W.
Object Type: Article
System: The UNT Digital Library
Advances in processing of Ag-sheathed (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} superconductors. (open access)

Advances in processing of Ag-sheathed (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} superconductors.

Advances in the processing and fabrication of Ag-sheathed (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} (Bi-2223) high-T{sub c} superconductors by the powder-in-tube technique continue to bring this material closer to commercial applications. Enhancement of the transport critical current density (J{sub c}) of Ag-sheathed Bi-2223 tapes was achieved by increasing the packing density of the precursor powder, improving mechanical deformation, and adjusting the cooling rate. Long lengths (>150 m) of multifilamentary Bi-2223 tapes have been fabricated and carry critical currents (I{sub c}) of >50 A (J{sub c} {approx} 25 kA/cm{sup 2}) at 77 K in self-field. A 1260-m-long tape carried an I{sub c} of 18 A (J{sub c} {approx} 12 kA/cm{sup 2}) from end-to-end. Several prototype coils have been assembled from these long-length tapes. Recent progress in the fabrication of Bi-2223 tapes is presented in this paper.
Date: March 5, 1998
Creator: Balachandran, U.; Eror, N. G.; Haldar, P. & Lelovic, M.
Object Type: Article
System: The UNT Digital Library
Measurement of low levels of alpha in {sup 99}Mo product solutions. (open access)

Measurement of low levels of alpha in {sup 99}Mo product solutions.

The conclusions of this report are that molybdenum can effectively be separated from uranium and plutonium using TRU-Resin; and that separation of the {sup 99}Mo from the actinides will reduce the analyst's exposure and simplify analysis for the actinide elements.
Date: March 5, 1998
Creator: Conner, C.; Liberatore, M. W.; Sedlet, J. & Vandegrift, G. F.
Object Type: Article
System: The UNT Digital Library
Modeling the effect of irradiation and post-irradiation annealing on grain boundary composition in austenitic Fe-Cr-Ni alloys. (open access)

Modeling the effect of irradiation and post-irradiation annealing on grain boundary composition in austenitic Fe-Cr-Ni alloys.

Many irradiation effects in Fe-Cr-Ni alloys such as radiation-induced segregation, radiation-enhanced diffusion, and void swelling are known to vary with bulk alloy composition. The development of microstructural and microchemical changes during irradiation and during post-irradiation annealing is determined by the rate of diffusion of point defects and alloying elements. To accurately predict the changes in grain boundary chemistry due to radiation-induced segregation and post-irradiation annealing, the composition dependence of diffusion parameters, such as the migration energy, must be known. A model has been developed which calculates migration diffusivity. The advantages of this calculational method are that a single set of input parameters can be used for a wide range of bulk alloy compositions, and the effects of local order can easily be incorporated into the calculations. A description of the model is presented, and model calculations are compared to segregation measurements from seven different iron-chromium-nickel alloys, irradiated with protons to doses from 0.1 to 3.0 dpa at temperatures between 200 C and 600 C. Results show that segregation trends can be modeled using a single set of input parameters with the difference between model calculation and measurement being less than 5 at%, but usually less than 2 at%. Additionally, model …
Date: March 5, 1998
Creator: Allen, T.; Busby, J. T.; Kenik, E. A. & Was, G. S.
Object Type: Article
System: The UNT Digital Library
Spectroscopic determination of C{sub 2} in Ar/H{sub 2}/CH{sub 4} and Ar/H{sub 2}/C{sub 60} microwave plasmas for nanocrystalline diamond synthesis. (open access)

Spectroscopic determination of C{sub 2} in Ar/H{sub 2}/CH{sub 4} and Ar/H{sub 2}/C{sub 60} microwave plasmas for nanocrystalline diamond synthesis.

We have measured the steady state concentration of gas phase C{sub 2} in Ar/H{sub 2}/CH{sub 4} and Ar/H{sub 2}/C{sub 60} microwave plasmas used for the deposition of nanocrystalline diamond films. High sensitivity white light absorption spectroscopy is used to monitor the C{sub 2} density using the d{sup 3}II {l_arrow} A{sup 3}II (0,0) vibrational band of C{sub 2} as chamber pressure, microwave power, substrate temperature and feed gas mixtures are varied in both chemistries. Understanding how these parameters influence the C{sub 2} density in the plasma volume provides insight into discharge mechanisms relevant to the deposition of nanocrystalline diamond.
Date: February 5, 1998
Creator: Goyette, A. N.; Lawler, J. E.; Anderson, L. W.; Gruen, D. M.; McCauley, T. G.; Zhou, D. et al.
Object Type: Article
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
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
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
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
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
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
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
Survey of high voltage electron microscopy worldwide in 1998. (open access)

Survey of high voltage electron microscopy worldwide in 1998.

High voltage TEMs were introduced commercially thirty years ago, with the installations of 500 kV Hitachi instruments at the Universities of Nagoya and Tokyo. Since that time 53 commercial instruments, having maximum accelerating potentials of 0.5-3.5 MV, will have been delivered by the end of 1998. Table 1 summarizes the sites and some information regarding those HVEMS which are available in 1998. This corrects, updates and expands an earlier report of this sort [2]. There have been three commercial HVEM manufacturers: AEI (UK), Hitachi and JEOL (Japan). The proportion of the total number of HVEMS produced by each manufacturer is similar to that reflected in Table 1: AEI and Kratos/AEI (12), Hitachi (20) and JEOL (21). The term Kratos/AEI refers to instruments delivered after the takeover of AEI by Grates in the late 1970's. In Table 1 only maximum accelerating potentials are listed, which is generally also the design value for which the resolution for imaging was optimized. It is important to realize that in many applications, especially those studying irradiation effects, much lower voltages may be employed somewhat routinely to minimize atom displacements by the incident electron beam during analysis. These minimum values range from 100 kV for the …
Date: March 5, 1998
Creator: Allen, C. W.
Object Type: Article
System: The UNT Digital Library
Regional emissions of air pollutants in China. (open access)

Regional emissions of air pollutants in China.

As part of the China-MAP program, sponsored by the US National Aeronautics and Space Administration, regional inventories of air pollutants emitted in China are being characterized, in order that the atmospheric chemistry over China can be more fully understood and the resulting ambient concentrations in Chinese cities and the deposition levels to Chinese ecosystems be determined with better confidence. In addition, the contributions of greenhouse gases from China and of acidic aerosols that counteract global warming are being quantified. This paper presents preliminary estimates of the emissions of some of the major air pollutants in China: sulfur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}), carbon monoxide (CO), and black carbon (C). Emissions are estimated for each of the 27 regions of China included in the RAINS-Asia simulation model and are subsequently distributed to a 1{degree} x 1{degree} grid using appropriate disaggregation factors. Emissions from all sectors of the Chinese economy are considered, including the combustion of biofuels in rural homes. Emissions from larger power plants are calculated individually and allocated to the grid accordingly. Data for the period 1990-1995 are being developed, as well as projections for the future under alternative assumptions about economic growth and environmental control.
Date: October 5, 1998
Creator: Streets, D. G.
Object Type: Article
System: The UNT Digital Library
Characterizing and modeling subarea-level energy transactions. (open access)

Characterizing and modeling subarea-level energy transactions.

This paper describes the application of an electrical network characterization method to an optimization model that is designed to simulate subarea-level energy transactions. The network characterization method determines subarea clusters of system buses that electrically respond to perturbations in a very similar manner. The method produces a reduced number of transmission constraints and preserves parallel path representations. The least-cost, linear programming (LP) formulation takes advantage of data reduction techniques to simplify model transmission constraints, while supporting parallel path system characteristics and energy tagging of subarea transactions. An overview of the proposed method describes the problem domain and key model features. The paper then presents two model applications that illustrate generator siting and line overload screening analyses.
Date: March 5, 1998
Creator: Kavicky, J. A.
Object Type: Article
System: The UNT Digital Library
D0 HVAC System Controls Evaluation of Upgrade Options (open access)

D0 HVAC System Controls Evaluation of Upgrade Options

This engineering note documents three different options for upgrading the Dzero HVAC control system. All three options leave the current field hardware and field devices intact and upgrade the computer control hardware and software. Dzero will be heading into a physics run starting in 2000. This physics run could last several years. The Dzero HVAC system is an integral part of climate control and electronics cooling. The current HVAC control system is based upon a 1985 Johnson Controls System. In order to enter the next long-term physics run with a solid HVAC control system, the current control system needs to be upgraded. This proposal investigates three options: (1) Replacement to the next generation of Johnson Controls Hardware and Software with the Johnson Controls operator interface - FESS; (2) Replacement to the next generation of Johnson Controls Hardware and Software with the FIX32 Operator Interface - FESS/Dzero; and (3) Replacement with a commercially available Programmable Logic Controller (PLC) WITH THE FIX 32 Operator Interface - Dzero.
Date: May 5, 1998
Creator: Markley, D. & Simon, P.
Object Type: Report
System: The UNT Digital Library
Carbon transport in the bottom boundary layer. Final report (open access)

Carbon transport in the bottom boundary layer. Final report

This report summarizes the activities and findings from a field experiment devised to estimate the rates and mechanisms of transport of carbon across the continental shelves. The specific site chosen for the experiment was the mid-Atlantic Bight, a region off the North Carolina coast. The experiment involved a large contingent of scientists from many institutions. The specific component of the program was the transport of carbon in the bottom boundary layer. The postulate mechanisms of transport of carbon in the bottom boundary layer are: resuspension and advection, downward deposition, and accumulation. The high turbulence levels in the bottom boundary layer require the understanding of the coupling between turbulence and bottom sediments. The specific issues addressed in the work reported here were: (a) What is the sediment response to forcing by currents and waves? (b) What is the turbulence climate in the bottom boundary layer at this site? and (c) What is the rate at which settling leads to carbon sequestering in bottom sediments at offshore sites?
Date: October 5, 1998
Creator: Agrawal, Yogesh C.
Object Type: Report
System: The UNT Digital Library