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Application of a Dynamic Fuzzy Search Algorithm to Determine Optimal Wind Plant Sizes and Locations in Iowa

Description: This paper illustrates a method for choosing the optimal mix of wind capacity at several geographically dispersed locations. The method is based on a dynamic fuzzy search algorithm that can be applied to different optimization targets. We illustrate the method using two objective functions for the optimization: maximum economic benefit and maximum reliability. We also illustrate the sensitivity of the fuzzy economic benefit solutions to small perturbations of the capacity selections at each wind site. We find that small changes in site capacity and/or location have small effects on the economic benefit provided by wind power plants. We use electric load and generator data from Iowa, along with high-quality wind-speed data collected by the Iowa Wind Energy Institute.
Date: September 21, 2001
Creator: Milligan, M. R., National Renewable Energy Laboratory & Factor, T., Iowa Wind Energy Institute
Partner: UNT Libraries Government Documents Department

Egress Shielding Studies for the SNS Accelerator System

Description: The radiation transport and dose levels at four egresses located in the Spallation Neutron Source (SNS) accelerator system were analyzed based on controlled and uncontrolled beam losses in the accelerator system. A six-step hybrid Monte Carlo/Discrete Ordinates approach was employed to solve these problems using the Monte Carlo code MCNPX and the discrete ordinates code DORT along with the coupling tools MTD and DTD. MCNPX served to characterize the generation and leakage of secondary radiation from the accelerator and beam line structures, whereas DORT performed the analyses of the radiation fields (neutrons and gammas) in the accelerator tunnels and walkways of the egress. The coupling tools facilitated generation of the boundary sources from one transport step to the next step. In this effort, large detailed accelerator models were built for MCNPX to properly describe the different types of linac structures, the beam transport and focusing elements (dipoles, quadrupoles, sextupoles) , and the beam collimators. The studies confirmed that the present egress designs were adequate to attenuate the dose in the linac tunnel of up to 100 rem/hr to a level of about 0.5 mrem/hr at the egress exit during normal operation. The egress in the accumulator ring is located at the entrance of the collimator section, a section with a high beam loss rate. For this reason, a dose level in the tunnel of 400 rem/hr was estimated along with a dose level at the exit of the egress of {approx}3 mrem/hr, which makes it a limited occupancy radiation area.
Date: August 21, 2001
Creator: Bucholz, JA
Partner: UNT Libraries Government Documents Department

Short-Term Output Variations in Wind Farms--Implications for Ancillary Services in the United States: Preprint

Description: With the advent of competition in the electric power marketplace, this paper reviews changes that affect wind and other renewable energy technologies, and discusses the role of federal and state policies in the recent wind installations in the United States. In particular, it reviews the implications of ancillary service requirements on a wind farm and presents initial operating results of monitoring one Midwest wind farm. Under federal energy policy, each generator must purchase, or otherwise provide for, ancillary services, such as dispatch, regulation, operation reserve, voltage regulation, and scheduling required to move power to load. As a renewable technology that depends on the forces of nature, short-term output variations are inherently greater for a wind farm than for a gas-fired combined cycle or a supercritical coal-fired unit.
Date: September 21, 2001
Creator: Cadogan, J.; Milligan, M.; Wan, Y. & Kirby, B.
Partner: UNT Libraries Government Documents Department

Burnup of Cadmium Decoupler Material in the Spallation Neutron Source Moderators

Description: At the Spallation Neutron Source being constructed at Oak Ridge National Laboratory, power levels will be greater than at any other operating pulsed spallation neutron scattering facility. Some of the moderators at the facility will contain cadmium that will be used to tailor neutron time distributions by absorbing low-energy neutrons. Because of the higher operating power levels, indications are that there will be considerable burnup of this cadmium during the lifetime of the moderators. Cadmium burnup rates have been calculated for locations around the moderators. Assumed operating conditions for these calculations were a 2-mA beam of 1-GeV protons on the mercury target for 5,000 operating hours per year and a three-year lifetime for the moderators and inner-plug assembly. With the present proposed cadmium thickness in the moderator region (0.05 cm), Monte Carlo calculations indicate considerable depletion of the active cadmium isotope. In places, the calculations indicate complete depletion. An obvious solution to the problem would be to increase the cadmium thickness with a concomitant increase in heat load. Results from some cadmium heating calculations are also presented for a cadmium thickness of 0.05 cm.
Date: August 21, 2001
Creator: Murphy, BD
Partner: UNT Libraries Government Documents Department

The Very Large Hadron Collider: The farthest energy frontier

Description: The Very Large Hadron Collider (or Eloisatron) represents what may well be the final step on the energy frontier of accelerator-based high energy physics. While an extremely high luminosity proton collider at 100-200 TeV center of mass energy can probably be built in one step with LHC technology, that machine would cost more than what is presently politically acceptable. This talk summarizes the strategies of collider design including staged deployment, comparison with electron-positron colliders, opportunities for major innovation, and the technical challenges of reducing costs to manageable proportions. It also presents the priorities for relevant R and D for the next few years.
Date: June 21, 2001
Creator: Barletta, William A.
Partner: UNT Libraries Government Documents Department

Performance Assessment of the Waste Dislodging Conveyance System During the Gunite And Associated Tanks Remediation Project

Description: The Waste Dislodging and Conveyance System (WD and CS) and other components of the Tank Waste Retrieval System (TWRS) were developed to address the need for removal of hazardous wastes from underground storage tanks (USTs) in which radiation levels and access limitations make traditional waste retrieval methods impractical. Specifically, these systems were developed for cleanup of the Gunite and Associated Tanks (GAAT) Operable Unit (OU) at the Oak Ridge National Laboratory (ORNL). The WD and CS is comprised of a number of different components. The three primary hardware subsystems are the Hose Management System (HMS), the Confined Sluicing End-Effector (CSEE), and the Flow Control Equipment and Containment Box (FCE/CB). In addition, a Decontamination Spray Ring (DSR) and a control system were developed for the system. The WD and CS is not a stand-alone system; rather, it is designed for deployment with either a long-reach manipulator like the Modified Light Duty Utility Arm (MLDUA) or a remotely operated vehicle system such as the Houdini{trademark}. The HMS was designed to act as a pipeline for the transfer of dislodged waste; as a hose-positioning and tether-management system; and as a housing for process equipment such as the water-powered jet pump that provides the necessary suction to vacuum slurried waste from the UST. The HMS was designed to facilitate positioning of an end-effector at any point within the 25-ft- or 50-ft-diameter USTs in the GAAT OU.
Date: February 21, 2001
Creator: Lloyd, P.D.
Partner: UNT Libraries Government Documents Department

PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP, RHIC SPIN PHYSICS V, VOLUME 32, FEBRUARY 21, 2001.

Description: The RIKEN BNL Research Center (RBRC) was established in April 1997 at Brookhaven National Laboratory. It is funded by the ''Rikagaku Kenkysho'' (RIKEN, The Institute of Physical and Chemical Research) of Japan. The Center is dedicated to the study of strong interactions, including spin physics, lattice QCD and RHIC physics through the nurturing of a new generation of young physicists. During the fast year, the Center had only a Theory Group. In the second year, an Experimental Group was also established at the Center. At present, there are seven Fellows and nine post dots in these two groups. During the third year, we started a new Tenure Track Strong Interaction Theory RHIC Physics Fellow Program, with six positions in the academic year 1999-2000; this program will increase to include eleven theorists in the next academic year, and, in the year after, also be extended to experimental physics. In addition, the Center has an active workshop program on strong interaction physics, about ten workshops a year, with each workshop focused on a specific physics problem. Each workshop speaker is encouraged to select few of the most important transparencies from his or her presentation, accompanied by a page of explanation. This material is collected at the end of the workshop by the organizer to form proceedings, which can therefore be available within a short time. The construction of a 0.6 teraflop parallel processor, which was begun at the Center on February 19, 1998, was completed on August 28, 1998.
Date: February 21, 2001
Creator: Bunce, G.; Saito, N.; Vigdor, S.; Roser, T.; Spinka, H.; Enyo, H. et al.
Partner: UNT Libraries Government Documents Department

Ground-Coupled Heat and Moisture Transfer from Buildings; Part 2: Application (Preprint)

Description: In this paper the effects of moisture on the heat transfer from two basic types of building foundations, a slab-on-grade and a basement, are examined. A two-dimensional finite element heat and moisture transfer program is used to show the effects of precipitation, soil type, foundation insulation, water table depth, and freezing on the heat transfer from the building foundation. Comparisons are made with a simple heat conduction model to illustrate the dependency of the soil thermal conductivity on moisture content.
Date: February 21, 2001
Creator: Deru, M.P. (National Renewable Energy Laboratory) & Kirkpatrick, A.T. (Colorado State University)
Partner: UNT Libraries Government Documents Department

Theory of Neutrino Flavor Mixing

Description: The depth of the authors theoretical understanding of neutrino flavor mixing should match the importance of this phenomenon as a herald of long-awaited empirical challenges to the standard model of particle physics. After reviewing the familiar, simplified quantum mechanical model and its flaws, the author sketches the deeper understanding of both vacuum and matter-enhanced flavor mixing that is found in the framework of scattering theory. While the model simplified gives the correct answer for atmospheric, solar, and accelerator/reactor neutrino phenomena, he argues that a key insight from the deeper picture will simplify the treatment of neutrino transport in astrophysical environments--supernovae, for example--in which neutrinos play a dynamically important role.
Date: August 21, 2001
Creator: Cardall, C. Y.
Partner: UNT Libraries Government Documents Department

Primary ion sources for EBIS

Description: This paper gives an introduction into the topic of primary ion sources that can be used to feed ions of normally solid elements into EBIS devices. Starting with a set of typical requirements for primary ion sources, some major types of ion generators are discussed first, with emphasis on their working principles rather than trying to give a fully representative listing of used and proposed generators. Beam-transport issues between primary ion source and EBIS are then examined, and generic characteristics of suitable beam-formation and transport systems are explained.
Date: March 21, 2001
Creator: Keller, R.
Partner: UNT Libraries Government Documents Department

NewtonPlus: Approximating Relativistic Effects in Supernova Simulations

Description: We propose an approximation to full relativity that captures the main gravitational effects of dynamical importance in supernovae. The conceptual link between this formalism and the Newtonian limit is such that it could likely be implemented relatively easily in existing multidimensional Newtonian gravitational hydrodynamics codes employing a Poisson solver. As a test of the formalism's utility, we display results for rapidly rotating (and therefore highly deformed) neutron stars.
Date: August 21, 2001
Creator: Cardall, C.Y.
Partner: UNT Libraries Government Documents Department

Ultralow Concentration Mercury Treatment Using Chemical Reduction and Air Stripping

Description: Field, laboratory and engineering data confirmed the efficacy of chemical reduction and air stripping as an ultralow concentration mercury treatment concept for water containing Hg(II). The simple process consists of dosing the water with low levels of stannous chloride (Sn(II)) to cover the mercury to Hg degrees. This mercury species can easily be removed from the water by air stripping or sparging.
Date: May 21, 2001
Creator: Looney, B.B.
Partner: UNT Libraries Government Documents Department

Cermet Transport, Storage, and Disposal Packages Using Depleted Uranium Dioxide and Steel

Description: It is proposed that the steel components of spent nuclear fuel (SNF) storage casks, transport casks, and repository waste packages (WPs) be replaced with a depleted uranium dioxide (DUO{sub 2})-steel cermet consisting of DUO{sub 2} particulates embedded in a continuous-steel phase. Typical cermets use a sandwich-type construction with clean uncontaminated steel layers on both sides of the cermet. Cermets have several potential advantages over other materials of construction: (1) better gamma and neutron shielding than steel; (2) ability to withstand extreme conditions (fire, accident, sabotage); (3) potential to improve repository performance when used in WPs; and (4) use of excess DUO{sub 2} and recycled steel from nuclear facilities, thereby avoiding disposal costs for these materials. New methods of manufacture and other factors may provide economic incentives for cermet packages when large numbers of casks are manufactured.
Date: August 21, 2001
Creator: Forsberg, C.W.
Partner: UNT Libraries Government Documents Department

PRECISION MEASUREMENT OF MUON G-2 AND ACCELERATOR RELATED ISSUES

Description: A precision measurement of the anomalous g value, a{sub {mu}}=(g-2)/2, for the positive muon has been made using high intensity protons available at the Brookhaven AGS. The result based on the 1999 data a{sub {mu}}=11659202(14)(6) x 10{sup 10} (1.3ppm) is in good agreement with previous measurements and has an error one third that of the combined previous data. The current theoretical value from the standard model is a{sub {mu}} (SM)=11659159.6(6.7) x 10{sup 10} (0.57 ppm) and differ by over 2.5 standard deviation with experiment. Issues with reducing systematic errors and enhancing the injection and storage efficiencies are discussed.
Date: September 21, 2001
Creator: BROWN,H.N.; BUNCE,G.; CAREY,R.M.; CUSHMAN,P.; DANBY,G.T.; DEBEVEC,P.T. et al.
Partner: UNT Libraries Government Documents Department

Neutronics studies for a long-wavelength target station at SNS.

Description: The Spallation Neutron Source (SNS), under construction at Oak Ridge National Laboratory, will be the premier facility for neutron scattering studies in the United States. From the outset the SNS can achieve additional flexibility and accommodate a broader range of scientific investigation than would be possible with only the High Power Target Station by utilizing two target stations, each operating under a separate set of conditions and optimized for a certain class of instruments. A second target station, termed the Long-Wavelength Target Station (LWTS), would operate at a lower pulse rate (e.g., 10 vs. 60 Hz) and utilize very cold moderators to emphasize low-energy (long wavelength) neutrons. The LWTS concept discussed here obtains the highest low-energy fluxes possible for neutron scattering instruments by using a heavy-water-cooled solid tungsten target with two moderators in slab geometry and one in a front wing position. The primary focus has been on solid methane moderators, with liquid methane and hydrogen also considered. We used MCNPX to conduct a series of optimization and sensitivity studies to help determine the optimal neutronic parameters of the LWTS. We compared different options based on the thermal and epithermal fluxes as determined by fitting the spectral intensity of the moderators with a Maxwellian peak and a modified Westcott function. The primary parameters are the moderator positions and composition and the target size. We report results for spectral intensity, pulse shapes, high-energy neutron emission, heating profiles in the target, and target activation.
Date: September 21, 2001
Creator: Micklich, B. J.; Iverson, E. B. & Carpenter, J. M.
Partner: UNT Libraries Government Documents Department

Experimental verification of caustic-side solvent extraction for removal of cesium from tank waste.

Description: The objectives of this report are: to demonstrate complete CSSX process flowsheet (proof of concept)--decontamination factor {ge} 40,000, and concentration factor {approx}15; Scientific and technical issues evaluated--stage efficiency, temperature control, hydraulic performance, long time (multi-day) operation, short-term shutdown, effect of solids, and recovery from Cs moving through strip section.
Date: September 21, 2001
Creator: Leonard, R. A.; Aase, S. B.; Arafat, H. A.; Chamberlain, D. B.; Conner, C.; Regalbuto, M. C. et al.
Partner: UNT Libraries Government Documents Department

The Particle Cleanliness Validation System

Description: The Particle Cleanliness Validation System (PCVS) is a combination of a surface particle collection tool and a microscope based data, reduction system for determining the particle cleanliness of mechanical and optical surfaces at LLNL. Livermore is currently constructing the National Ignition Facility (NIF), a large 192 beam laser system for studying fusion physics. The laser is entirely enclosed. in aluminum and stainless steel vessels containing several environments; air, argon, and vacuum. It contains uncoated optics as well as hard dielectric coated and softer solgel coated optics which are, to varying degrees, sensitive to opaque particles, translucent particles, and molecular contamination. To quantify the particulate matter on structural surfaces during vendor cleaning and installation, a novel instrument has been developed to-both collect surface particles and to quantify the number and size distribution of these particles. The particles are collected on membrane filter paper which is ''swiped'' on a test surface for a proscribed distance to collect sufficient particles to significantly exceed the cleanliness of the filter paper. The swipe paper is then placed into a cassette for protection from further. contamination and transported to a microscope with x-y motorized stage and image analysis software, The surface of the swipe paper is scanned to determine both the background particle level of the paper, the cassette cover, and the portion of the paper which made contact with the test surface. The cumulative size distribution of the collected particles are displayed in size bins from 5 to 200 {micro}m. The quantity of particles exceeding 5 {micro}m is used to compute the IEST-STD-1246D cleanliness Level. Eight image analysis microscopes have been constructed for use with several dozen particle collection tools. About 30,000 cleanliness measurements have been taken to assure the clean construction and operation of the NIF laser system.
Date: December 21, 2001
Creator: Stowers, I.F. & Ravizza, D.L.
Partner: UNT Libraries Government Documents Department

Adapting MARSSIM for FUSRAP site closure.

Description: The Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM) provides a coherent, technically defensible process for establishing that exposed surfaces satisfy site cleanup requirements. Unfortunately, many sites have complications that challenge a direct application of MARSSIM. Example complications include Record of Decision (ROD) requirements that are not MARSSIM-friendly, the potential for subsurface contamination, and incomplete characterization information. These types of complications are typically the rule, rather than the exception, for sites undergoing radiologically-driven remediation and closure. One such site is the Formerly Utilized Sites Remedial Action Program (FUSRAP) Linde site in Tonawanda, New York. Cleanup of the site is currently underway. The Linde site presented a number of challenges to designing and implementing a closure strategy consistent with MARSSIM. This paper discusses some of the closure issues confronted by the U.S. Army Corps of Engineers Buffalo District at the Linde site, and describes how MARSSIM protocols were adapted to address these issues.
Date: December 21, 2001
Creator: Johnson, R.; Durham, L.; Rieman, C. & Hoover, R.
Partner: UNT Libraries Government Documents Department

Isotopically controlled semiconductors

Description: Semiconductor bulk crystals and multilayer structures with controlled isotopic composition have attracted much scientific and technical interest in the past few years. Isotopic composition affects a large number of physical properties, including phonon energies and lifetimes, bandgaps, the thermal conductivity and expansion coefficient and spin-related effects. Isotope superlattices are ideal media for self-diffusion studies. In combination with neutron transmutation doping, isotope control offers a novel approach to metal-insulator transition studies. Spintronics, quantum computing and nanoparticle science are emerging fields using isotope control.
Date: December 21, 2001
Creator: Haller, Eugene E.
Partner: UNT Libraries Government Documents Department

Aspects of Coulomb dissociation and interference in peripheral nucleus-nucleus collisions

Description: Coherent vector meson production in peripheral nucleus-nucleus collisions is discussed. These interactions may occur for impact parameters much larger than the sum of the nuclear radii. Since the vector meson production is always localized to one of the nuclei, the system acts as a two-source interferometer in the transverse plane. By tagging the outgoing nuclei for Coulomb dissociation it is possible to obtain a measure of the impact parameter and thus the source separation in the interferometer. This is of particular interest since the life-time of the vector mesons are generally much shorter than the impact parameters of the collisions.
Date: October 21, 2001
Creator: Nystrand, Joakim; Baltz, Anthony & Klein, Spencer R.
Partner: UNT Libraries Government Documents Department