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Simplified modeling for infiltration and radon entry (open access)

Simplified modeling for infiltration and radon entry

Air leakage in the envelopes of residential buildings is the primary mechanism for provided ventilation to those buildings. For radon the same mechanisms that drive the ventilation, drive the radon entry This paper attempts to provide a simplified physical model that can be used to understand the interactions between the building leakage distribution, the forces that drive infiltration and ventilation, and indoor radon concentrations, Combining both ventilation and entry modeling together allows an estimation of Radon concentration and exposure to be made and demonstrates how changes in the envelope or ventilation system would affect it. This paper will develop simplified modeling approaches for estimating both ventilation rate and radon entry rate based on the air tightness of the envelope and the driving forces. These approaches will use conventional leakage values (i.e. effective leakage area ) to quantify the air tightness and include natural and mechanical driving forces. This paper will introduce a simplified parameter, the Radon Leakage Area, that quantifies the resistance to radon entry. To be practical for dwellings, modeling of the occupant exposures to indoor pollutants must be simple to use and not require unreasonable input data. This paper presents the derivation of the simplified physical model, and …
Date: August 1, 1992
Creator: Sherman, M. H.
System: The UNT Digital Library
Office of Technology Development integrated program for development of in situ remediation technologies (open access)

Office of Technology Development integrated program for development of in situ remediation technologies

The Department of Energy's Office of Technology Development has instituted an integrated program focused on development of in situ remediation technologies. The development of in situ remediation technologies will focus on five problem groups: buried waste, contaminated soils, contaminated groundwater, containerized wastes and underground detonation sites. The contaminants that will be included in the development program are volatile and non volatile organics, radionuclides, inorganics and highly explosive materials as well as mixtures of these contaminants. The In Situ Remediation Integrated Program (ISR IP) has defined the fiscal year 1993 research and development technology areas for focusing activities, and they are described in this paper. These R D topical areas include: nonbiological in situ treatment, in situ bioremediation, electrokinetics, and in situ containment.
Date: August 1, 1992
Creator: Peterson, M.
System: The UNT Digital Library
Electron correlations in semiconductors: Bulk cohesive properties and magnetic-field-induced Wigner crystal at heterojunctions (open access)

Electron correlations in semiconductors: Bulk cohesive properties and magnetic-field-induced Wigner crystal at heterojunctions

A correlated wavefunction variational quantum Monte Carlo approach to the studies of electron exchange and correlation effects in semiconductors is presented. Applications discussed include the cohesive and structural properties of bulk semiconductors, and the magnetic-field-induced Wigner electron crystal in two dimensions. Landau level mixing is shown to be important in determining the transition between the quantum Hall liquid and the Wigner crystal states in the regime of relevant experimental parameters.
Date: August 1, 1992
Creator: Louie, S.G. & Zhu, X.
System: The UNT Digital Library
Accelerator physics analysis with an integrated toolkit (open access)

Accelerator physics analysis with an integrated toolkit

Work is in progress on an integrated software toolkit for linear and nonlinear accelerator design, analysis, and simulation. As a first application, beamline'' and MXYZPTLK'' (differential algebra) class libraries, were used with an X Windows graphics library to build an user-friendly, interactive phase space tracker which, additionally, finds periodic orbits. This program was used to analyse a theoretical lattice which contains octupoles and decapoles to find the 20th order, stable and unstable periodic orbits and to explore the local phase space structure.
Date: August 1, 1992
Creator: Holt, J.A.; Michelotti, L. & Satogata, T.
System: The UNT Digital Library
Superconducting accelerator magnets: A review of their design and training (open access)

Superconducting accelerator magnets: A review of their design and training

This paper reviews the basic mechanical designs of most of the superconducting magnets developed for high energy hadron accelerators. The training performance of these magnets is compared with an instability factor defined by the square of the current density in the stabilizing copper divided by the surface-to-volume ratio of the strands. A good correlation is observed.
Date: August 1, 1992
Creator: Palmer, R.B. (Stanford Linear Accelerator Center, Menlo Park, CA (United States) Brookhaven National Lab., Upton, NY (United States))
System: The UNT Digital Library
Organic acid modeling and model validation: Workshop summary (open access)

Organic acid modeling and model validation: Workshop summary

A workshop was held in Corvallis, Oregon on April 9--10, 1992 at the offices of E S Environmental Chemistry, Inc. The purpose of this workshop was to initiate research efforts on the entitled Incorporation of an organic acid representation into MAGIC (Model of Acidification of Groundwater in Catchments) and testing of the revised model using Independent data sources.'' The workshop was attended by a team of internationally-recognized experts in the fields of surface water acid-bass chemistry, organic acids, and watershed modeling. The rationale for the proposed research is based on the recent comparison between MAGIC model hindcasts and paleolimnological inferences of historical acidification for a set of 33 statistically-selected Adirondack lakes. Agreement between diatom-inferred and MAGIC-hindcast lakewater chemistry in the earlier research had been less than satisfactory. Based on preliminary analyses, it was concluded that incorporation of a reasonable organic acid representation into the version of MAGIC used for hindcasting was the logical next step toward improving model agreement.
Date: August 14, 1992
Creator: Sullivan, T.J. & Eilers, J.M.
System: The UNT Digital Library
Decoherence of multimode thermal squeezed coherent states (open access)

Decoherence of multimode thermal squeezed coherent states

It is well known that any multimode positive definite quadratic Hamiltonian can be transformed into a hamiltonian of uncoupled harmonic oscillators. Based on this theorem, the multimode thermal squeezed coherent states are constructed in terms of density operators. Decoherence of multimode thermal squeezed coherent states in investigated via the characteristic function and it is shown that the decohered (reduced) states are still thermal squeezed coherent states in general.
Date: August 14, 1992
Creator: Yeh, L.
System: The UNT Digital Library
High Heat Load Synchrotron Optics (open access)

High Heat Load Synchrotron Optics

Third generation synchrotron radiation sources currently being constructed worldwide will produce x-ray beams of unparalleled power and power density these high heat fluxes coupled with the stringent dimensional requirements of the x-ray optical components pose a prodigious challenge to designers of x-ray optical elements, specifically x-ray mirrors and crystal monochromators. Although certain established techniques for the cooling of high heat flux components can be directly applied to this problem, the thermal management of high heat load x-ray optical components has several unusual aspects that may ultimately lead to unique solutions. This manuscript attempts to summarize the various approaches currently being applied to this undertaking and to point out the areas of research that require further development.
Date: August 1992
Creator: Mills, Dennis M.
System: The UNT Digital Library
A high resolution, single bunch, beam profile monitor (open access)

A high resolution, single bunch, beam profile monitor

Efficient linear colliders require very small beam spots to produce high luminosities with reasonable input power, which limits the number of electrons which can be accelerated to high energies. The small beams, in turn, require high precision and stability in all accelerator components. Producing, monitoring and maintaining beams of the required quality has been, and will continue to be, difficult. A beam monitoring system which could be used to measure beam profile, size and stability at the final focus of a beamline or collider has been developed and is described here. The system uses nonimaging bremsstrahlung optics. The immediate use for this system would be examining the final focus spot at the SLAC/FFTB. The primary alternatives to this technique are those proposed by P. Chen / J. Buon, which analyses the energy and angular distributions of ion recoils to determine the aspect ratio of the electron bunch, and a method proposed by Shintake, which measures intensity variation of compton backscattered photons as the beam is moved across a pattern of standing waves produced by a laser.
Date: August 26, 1992
Creator: Norem, J.
System: The UNT Digital Library
High energy elastic and diffractive scattering (open access)

High energy elastic and diffractive scattering

The developments in high energy pp and p{bar p} elastic scattering in the last 30 years are summarized. The Regge pole model and the geometrical models are reviewed and their agreement with experimental data discussed. The experimental method for measuring the total cross section and the ratio of the real to the imaginary part of the forward elastic scattering amplitude, p, is described. The asymptotic behavior of the total cross section at high energy is discussed in the light of the new results on p{bar p} elastic scattering at {radical}s=1.8 TeV. Predictions from geometrical models and Regge phenomenology are compared with experimental data. The 2-gluon model of the Pomeron by Low and Nussinov is discussed. Future measurements on elastic pp and p{bar p} elastic scattering are discussed.
Date: August 1, 1992
Creator: Shukla, S.
System: The UNT Digital Library
Commercial building energy standards implementation: Myth vs reality (open access)

Commercial building energy standards implementation: Myth vs reality

Since the advent of building energy standards almost 20 years ago there have been numerous codes, standards, and regulations (herein after referred to as standards) developed, adopted, and applied to new commercial building design and construction. The development of these standards occurs primarily at the national level, while adoption and implementation occurs at the state and local levels of government. Many assume that the mere adoption of a standard ensures that compliance is achieved and energy conserving buildings automatically result from the process. This assumption accounts for the myth that all buildings are constructed in compliance with the adopted standard and in reality many are not. There are many different processes by which standards are adopted and actually implemented, and they directly affect how close reality is to the myth. The paper presents the different processes used throughout the US to adopt and implement building energy standards for new commercial buildings, reviews available studies on compliance, discusses the reasons for reduced compliance, and suggests programs to improve today's realities.
Date: August 1, 1992
Creator: Conover, D.R.; Jarnagin, R.E. & Shankle, D.
System: The UNT Digital Library
Reduced mass persistent switches for large superconducting magnets in space (open access)

Reduced mass persistent switches for large superconducting magnets in space

Superconducting magnets in space must operate in the persistent mode. This paper describes the characteristics of low mass niobium titanium persistent switches for low mass superconducting magnets which are designed to quench protect themselves through the quench back process. (The whole coil is driven normal shortly after the quench has started and the magnet stored energy is taken up by the coil and the persistent switch.) The concept Of using a resistor and diode in parallel with the persistent switch to reduce the overall mass of the persistent switch system and the helium consumption during magnet charging is discussed in the report. A 1.4 meter diameter free-flyer version of the 11.6 Mi stored energy ASTROMAG magnet and its persistent switch is presented as an example.
Date: August 1, 1992
Creator: Green, Michael A.
System: The UNT Digital Library
Modeling the uncertain impacts of climate change (open access)

Modeling the uncertain impacts of climate change

Human and earth systems are extremely complex processes. The modeling of these systems to assess the effects of climate change is an activity fraught with uncertainty. System models typically involve the linking of a series of computer codes, each of which is a detailed model of some physical or social process in its own right. In such system models, the output from one process model is the input to another. Traditional methods for dealing with uncertainty are inadequate because of the sheer complexity of the modeling effort: Monte Carlo methods and the exhaustive evaluation of what if '' scenarios estimate sensitivities fail because of the heavy computational burden. More efficient methods are required for learning about system models that are constructed from a collection of computer codes. A two-tiered modeling approach is being developed to estimate the distribution of outcomes from a series of nested models. The basic strategy is to develop a simplified executive, or simplified system code (SSC), that is analogous to the more complex underlying code. An essential feature of the SSC is that it uses information abstracted from the detailed underlying process codes in a manner that preserves their essential features and interactions among them. Of …
Date: August 1, 1992
Creator: Liebetrau, A.M.
System: The UNT Digital Library
Design of a superconducting linear accelerator for an Infrared Free Electron Laser of the proposed Chemical Dynamics Research Laboratory at LBL (open access)

Design of a superconducting linear accelerator for an Infrared Free Electron Laser of the proposed Chemical Dynamics Research Laboratory at LBL

An accelerator complex has recently been designed at LBL as part of an Infrared Free Electron Laser facility in support of a proposed Chemical Dynamics Research Laboratory. We will outline the choice of parameters and design philosophy, which are strongly driven by the demand of reliable and spectrally stable operation of the FEL for very special scientific experiments. The design is based on a 500 MHz recirculating superconducting electron linac with highest energy reach of about 60 MeV. The accelerator is injected with beams prepared by a specially designed gun-buncher system and incorporates a near-isochronous and achromatic recirculation line tunable over a wide range of beam energies. The stability issues considered to arrive at the specific design will be outlined.
Date: August 1, 1992
Creator: Chattopadhyay, S.; Byrns, R.; Donahue, R.; Edighoffer, J.; Gough, R.; Hoyer, E. et al.
System: The UNT Digital Library
Innovative technology demonstrations (open access)

Innovative technology demonstrations

Environmental Management Operations (EMO) is conducting an Innovative Technology Demonstration Program for Tinker Air Force Base (TAFB). Several innovative technologies are being demonstrated to address specific problems associated with remediating two contaminated test sites at the base. Cone penetrometer testing (CPT) is a form of testing that can rapidly characterize a site. This technology was selected to evaluate its applicability in the tight clay soils and consolidated sandstone sediments found at TAFB. Directionally drilled horizontal wells was selected as a method that may be effective in accessing contamination beneath Building 3001 without disrupting the mission of the building, and in enhancing the extraction of contamination both in ground water and in soil. A soil gas extraction (SGE) demonstration, also known as soil vapor extraction, will evaluate the effectiveness of SGE in remediating fuels and TCE contamination contained in the tight clay soil formations surrounding the abandoned underground fuel storage vault located at the SW Tanks Site. In situ sensors have recently received much acclaim as a technology that can be effective in remediating hazardous waste sites. Sensors can be useful for determining real-time, in situ contaminant concentrations during the remediation process for performance monitoring and in providing feedback for controlling …
Date: August 1, 1992
Creator: Anderson, D.B.; Luttrell, S.P. (Pacific Northwest Lab., Richland, WA (United States)); Hartley, J.N. (Pacific Northwest Lab., Richland, WA (United States). Environmental Management Operations) & Hinchee, R. (Battelle, Columbus, OH (United States))
System: The UNT Digital Library
Lipids: Part of the tangled web (open access)

Lipids: Part of the tangled web

Analysis of LDL subclasses by non-denaturing gradient gel electrophoresis has led to the identification of a subclass pattern characterized by predominance of small LDL, designated LDL subclass pattern B. The prevalence of pattern B in the general population is approximately 25%, but varies as a function of age and gender, being relatively uncommon in children and in premenopausal women. The remainder of the population has a predominance of larger LDL (pattern A) or an intermediate pattern. Our findings indicate that LDL subclass pattern B is an integral part of the tangled web'' of interrelated coronary disease risk factors associated with insulin resistance. It may be that the pathologic features of this lipoprotein profile, including the relative atherogenicity of small, dense LDL and IDL, contribute importantly to the increased risk of cardiovascular disease in subjects with insulin resistance and hypertension. Furthermore, pattern B serves as a marker for a common genetic trait which may underlie a substantial portion of the familial predisposition to coronary artery disease in the general population. Studies of hormonal, dietary, and pharmacologic influences on expression of this atherogenic phenotype should lead to more effective identification and management of high-risk individuals, and improved approaches to disease prevention in …
Date: August 1, 1992
Creator: Krauss, R. M.
System: The UNT Digital Library
The analysis of transverse beam tail distributions of bunches with non-Gaussian shapes (open access)

The analysis of transverse beam tail distributions of bunches with non-Gaussian shapes

The characterization of transverse particle distributions of bunches with non-Gaussian shapes is difficult due to a wide variety of possibilities. Without knowing additional information one can fit a distribution using first-, second-, third-, and higher order moments. These moments can then be used to describe beam shape changes along the accelerator, but with limited knowledge of the physics which caused the Perturbed shape. However, when the cause of the non-Gaussian distribution is known, a more detailed description of the particle distribution can be constructed. In the Stanford Linear Collider (SLC) non-Gaussian distributions are produced by transverse wakefields in the 3000 m linac.
Date: August 1, 1992
Creator: Avilov, M. S. & Seeman, J. T.
System: The UNT Digital Library
Local critical current measurements on (Bi,Pb) sub 2 Sr sub 2 Ca sub 2 Cu sub 3 O sub x tape with an electromagnetic probe (open access)

Local critical current measurements on (Bi,Pb) sub 2 Sr sub 2 Ca sub 2 Cu sub 3 O sub x tape with an electromagnetic probe

The ability to measure critical currents in high {Tc} superconducting tapes on a local scale is valuable for optimizing the fabrication process. This paper describes the use of induced currents from a small noncontacting electromagnetic probe to determine the critical current density in a (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x}/Ag tape on a local scale. The technique forces full field penetration into the tape locally and infers the critical current density from the Bean critical state model, accounting for the Ag overlayers. Critical current images of the till can be obtained by scanning the probe over the tape surface with spatial resolution on the order of 1.0 mm. Results for tapes with different microstructures we discussed.
Date: August 24, 1992
Creator: Telschow, K.L.; O'Brien, T.K. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Lanagan, M.T. & Kaufman, D.Y. (Argonne National Lab., IL (United States))
System: The UNT Digital Library
Suppression of mode-beating in a saturated hole-coupled FEL oscillator (open access)

Suppression of mode-beating in a saturated hole-coupled FEL oscillator

In a hole-coupled resonator, either empty or loaded with a linear FEL gain medium, the phenomenon of mode-degeneracy and mode-beating have been studied. When the magnitudes of the eigenvalues, derived from a linear analysis, are equal for two or more dominant eigenmodes, the system cannot achieve a stable beam-profile. We investigate this phenomenon when a saturated FEL is present within the cavity, thus introducing non-linearity. We use a three-dimensional FEL oscillator code, based on the amplifier code TDA, and show that mode-beating is completely suppressed in the nonlinear saturated regime. We suggest a simple, qualitative model for the mechanism responsible for this suppression.
Date: August 1, 1992
Creator: Krishnagopal, S.; Xie, M. & Kim, K. J.
System: The UNT Digital Library
Computer codes for RF cavity design (open access)

Computer codes for RF cavity design

In RF cavity design, numerical modeling is assuming an increasingly important role with the help of sophisticated computer codes and powerful yet affordable computers. A description of the cavity codes in use in the accelerator community has been given previously. The present paper will address the latest developments and discuss their applications to cavity toning and matching problems.
Date: August 1, 1992
Creator: Ko, K.
System: The UNT Digital Library
Infinite-mode squeezed coherent states and non-equilibrium statistical mechanics (phase-space-picture approach) (open access)

Infinite-mode squeezed coherent states and non-equilibrium statistical mechanics (phase-space-picture approach)

The phase-space-picture approach to quantum non-equilibrium statistical mechanics via the characteristic function of infinite- mode squeezed coherent states is introduced. We use quantum Brownian motion as an example to show how this approach provides an interesting geometrical interpretation of quantum non-equilibrium phenomena.
Date: August 14, 1992
Creator: Yeh, L.
System: The UNT Digital Library
Third harmonic rf cavity for transition crossing in the Main Ring (open access)

Third harmonic rf cavity for transition crossing in the Main Ring

This paper reports the present status and future plans of the implementation of the transition crossing RF harmonic system at Fermilab. The test is being carried out in the Main Ring (MR) which is used as a 150 GeV injector to the Tevatron.
Date: August 1, 1992
Creator: Bhat, C.M.
System: The UNT Digital Library
Engineering scaleup of electrical soil heating for soil decontamination (open access)

Engineering scaleup of electrical soil heating for soil decontamination

The objective of PNL's efforts in electrically based methods for environmental restoration is to provide new and cost-effective means for removing hazardous organic contaminants from soils, and to detoxify those contaminants after they are removed. Recent work has concentrated on two areas: electrical soil heating to remove volatile and semivolatile compounds from soils, and in situ oxidation via a form of low-temperature plasma to decompose nonvolatile and bound contaminants. This paper covers only the electrical soil heating component, and describes recent efforts to model the heating process to enable equipment and energy requirements to be specified. An initial field test of the heating process suggests that the model presented in this paper is correct, within the range of uncertainty in the spatial variations of soil properties. Because of page limitations, a description of this test and discussion of the test results will be relegated to a subsequent publication.
Date: August 1, 1992
Creator: Heath, W.O.; Roberts, J.S.; Lessor, D.E. & Bergsman, T.M.
System: The UNT Digital Library
Assessing the public regulatory acceptability of deploying new cleanup technologies: A case study of the integrated demonstration for Remediation of Volatile Organic Compounds at Arid Sites (open access)

Assessing the public regulatory acceptability of deploying new cleanup technologies: A case study of the integrated demonstration for Remediation of Volatile Organic Compounds at Arid Sites

The US Department of Energy (DOE) is funding several integrated demonstrations (IDs) around the United States in an effort to improve the pace and effectiveness of cleaning up its sites. The objective of these IDs is to demonstrate an array of innovative cleanup technologies that address the specific needs at a site and to provide deployable technologies to all DOE sites with similar environmental problems. This approach eliminates the need to redemonstrate these technologies at multiple sites, thereby minimizing technology development cost and schedule requirements. However, for an ID to be truly successful, the technologies must be technically sound, acceptable to the various interested or concerned individuals and groups who feel they have a stake in the case (often referred to as stakeholders), and acceptable to the regulators responsible for approving the technologies' deployment. As a result, the ID for Remediation of Volatile Organic Compounds at Arid Sites (VOC-Arid ID) has instituted a process for assessing public and regulatory acceptability of the technologies that it is developing. As part of this process, an information system has been developed that describes the innovative technologies being supported under the VOC-Arid ID. It also compares innovative technologies with the baseline technologies currently in …
Date: August 1, 1992
Creator: McCabe, G.H. (Battelle Seattle Research Center, WA (United States)) & Stein, S.L. (Battelle Pacific Northwest Div., Seattle, WA (United States))
System: The UNT Digital Library