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Using measured equipment load profiles to 'right-size' HVACsystems and reduce energy use in laboratory buildings (Pt. 2) (open access)

Using measured equipment load profiles to 'right-size' HVACsystems and reduce energy use in laboratory buildings (Pt. 2)

There is a general paucity of measured equipment load datafor laboratories and other complex buildings and designers often useestimates based on nameplate rated data or design assumptions from priorprojects. Consequently, peak equipment loads are frequentlyoverestimated, and load variation across laboratory spaces within abuilding is typically underestimated. This results in two design flaws.Firstly, the overestimation of peak equipment loads results in over-sizedHVAC systems, increasing initial construction costs as well as energy usedue to inefficiencies at low part-load operation. Secondly, HVAC systemsthat are designed without accurately accounting for equipment loadvariation across zones can significantly increase simultaneous heatingand cooling, particularly for systems that use zone reheat fortemperature control. Thus, when designing a laboratory HVAC system, theuse of measured equipment load data from a comparable laboratory willsupport right-sizing HVAC systems and optimizing their configuration tominimize simultaneous heating and cooling, saving initial constructioncosts as well as life-cycle energy costs.In this paper, we present datafrom recent studies to support the above thesis. We first presentmeasured equipment load data from two sources: time-series measurementsin several laboratory modules in a university research laboratorybuilding; and peak load data for several facilities recorded in anational energy benchmarking database. We then contrast this measureddata with estimated values that are typically used …
Date: June 29, 2005
Creator: Mathew, Paul; Greenberg, Steve; Frenze, David; Morehead, Michael; Sartor, Dale & Starr, William
System: The UNT Digital Library
Surface Specularity as an Indicator of Shock-Induced Solid-Liquid Phase Transitions (open access)

Surface Specularity as an Indicator of Shock-Induced Solid-Liquid Phase Transitions

When highly polished metal surfaces melt upon release after shock loading, they exhibit a number of features that suggest that significant surface changes accompany the phase transition. The reflection of light from such surfaces changes from specular (pre-shock) to diffuse upon melting. A familiar manifestation of this phenomenon is the loss of signal light in velocimetric measurements typically observed above pressures high enough to melt the free-surface. Unlike many other potential material phase-sensitive diagnostics (e.g., reflectometery, conductivity), changes in the specularity of reflection provide a dramatic, sensitive indicator of the solid-liquid phase transition. Data will be presented from multiple diagnostics that support the hypothesis that specularity changes indicate melt. These diagnostics include shadowgraphy, infrared imagery, high-magnification surface images, interferometric velocimetry, and most recently scattering angle measurements.
Date: June 29, 2007
Creator: Gerald Stevens, Stephen Lutz, William Turley, Lynn Veeser
System: The UNT Digital Library
Shape transitions in neutron-rich Ru isotopes: spectroscopy of 109,110,111,112Ru (open access)

Shape transitions in neutron-rich Ru isotopes: spectroscopy of 109,110,111,112Ru

The spectroscopy of neutron-rich {sup 109,110,111,112}Ru nuclei was studied by measuring the prompt {gamma} rays originated from fission fragments, produced by the {sup 238}U({alpha},f) fusion-fission reaction, in coincidence with the detection of both fragments. For {sup 109,111}Ru, both the negative-parity (h{sub 11/2} orbitals) and positive-parity (g{sub 7/2} and/or d{sub 5/2} orbitals) bands were extended to substantially higher spin and excitation energy than known previously. The ground-state and {gamma}-vibrational bands of {sup 110,112}Ru also were extended to higher spin, allowing observation of the second band crossing at the rotational frequency of {approx}450 keV in {sup 112}Ru, which is {approx}50 keV above the first band crossing. At a similar rotational frequency, the first band crossing for the h{sub 11/2} band in {sup 111}Ru was observed, which is absent in {sup 109}Ru. These band crossings most likely are caused by the alignment of the g{sub 9/2} proton pair. This early onset of the band crossing for the aligned {pi}g{sub 9/2} orbitals may be evidence of a triaxial shape transition from prolate to oblate occurring in {sup 111}Ru. The data together with a comparison of cranked shell model predictions are presented.
Date: June 29, 2005
Creator: Hua, H.; Cline, D.; Hayes, A. B.; Teng, R.; Riley, D.; Clark, R. M. et al.
System: The UNT Digital Library
Poroelastic modeling of seismic boundary conditions across afracture (open access)

Poroelastic modeling of seismic boundary conditions across afracture

A fracture within a porous background is modeled as a thin porous layer with increased compliance and finite permeability. For small layer thickness, a set of boundary conditions can be derived that relate particle velocity and stress across a fracture, induced by incident poroelastic waves. These boundary conditions are given via phenomenological parameters that can be used to examine and characterize the seismic response of a fracture. One of these parameters, here it is called membrane permeability, is shown through several examples to control the scattering amplitude of the slow P waves for very low-permeability fractures, which in turn controls the intrinsic attenuation of the waves.
Date: June 29, 2006
Creator: Schoenberg, M.A. & Nakagawa, S.
System: The UNT Digital Library
Residential implementation of critical-peak pricing ofelectricity (open access)

Residential implementation of critical-peak pricing ofelectricity

This paper investigates how critical-peak pricing (CPP)affects households with different usage and income levels, with the goalof informing policy makers who are considering the implementation of CPPtariffs in the residential sector. Using a subset of data from theCalifornia Statewide Pricing Pilot of 2003-2004, average load changeduring summer events, annual percent bill change, and post-experimentsatisfaction ratings are calculated across six customer segments,categorized by historical usage and income levels. Findings show thathigh-use customers respond significantly more in kW reduction than dolow-use customers, while low-use customers save significantly more inpercentage reduction of annual electricity bills than do high-usecustomers results that challenge the strategy of targeting only high-usecustomers for CPP tariffs. Across income levels, average load and billchanges were statistically indistinguishable, as were satisfaction ratesresults that are compatible with a strategy of full-scale implementationof CPP rates in the residential sector. Finally, the high-use customersearning less than $50,000 annually were the most likely of the groups tosee bill increases about 5 percent saw bill increases of 10 percent ormore suggesting that any residential CPP implementation might considertargeting this customer group for increased energy efficiencyefforts.
Date: June 29, 2006
Creator: Herter, Karen
System: The UNT Digital Library
Modelling of e-cloud build-up in grooved vacuum chambers usingPOSINST (open access)

Modelling of e-cloud build-up in grooved vacuum chambers usingPOSINST

Use of grooved vacuum chambers have been suggested as a wayto limitelectron cloud accumulation in the ILC-DR. We report onsimulations carried out using an augmented version of POSINST, accountingfor e-cloud dynamics in the presence of grooves, and make contact withprevious estimates of an effective secondary electron yield for groovedsurfaces.
Date: June 29, 2007
Creator: Venturini, Marco; Celata, C.; Furman, Miguel; Vay, Jean-Luc & Pivi, Mauro
System: The UNT Digital Library
In situ laser heating and radial synchrotron X-ray diffraction ina diamond anvil cell (open access)

In situ laser heating and radial synchrotron X-ray diffraction ina diamond anvil cell

We report a first combination of diamond anvil cell radialx-ray diffraction with in situ laser heating. The laser-heating setup ofALS beamline 12.2.2 was modified to allow one-sided heating of a samplein a diamond anvil cell with an 80 W yttrium lithium fluoride laser whileprobing the sample with radial x-ray diffraction. The diamond anvil cellis placed with its compressional axis vertical, and perpendicular to thebeam. The laser beam is focused onto the sample from the top while thesample is probed with hard x-rays through an x-ray transparentboron-epoxy gasket. The temperature response of preferred orientation of(Fe,Mg)O is probed as a test experiment. Recrystallization was observedabove 1500 K, accompanied by a decrease in stress.
Date: June 29, 2007
Creator: Kunz, Martin; Caldwell, Wendel A.; Miyagi, Lowell & Wenk,Hans-Rudolf
System: The UNT Digital Library
Calibration of symmetric and non-symmetric errors for interferometry of ultra-precise imaging systems (open access)

Calibration of symmetric and non-symmetric errors for interferometry of ultra-precise imaging systems

The azimuthal Zernike coefficients for shells of Zernike functions with shell numbers n<N may be determined by making measurements at N equally spaced rotational positions. However, these measurements do not determine the coefficients of any of the purely radial Zernike functions. Label the circle that the azimuthal Zernikes are measured in as circle A. Suppose that the azimuthal Zernike coefficients for n<N are also measured in a smaller circle B which is inside circle A but offset so that it is tangent to circle A and so that it has the center of circle A just inside its circular boundary. The diameter of circle B is thus only slightly larger than half the diameter of circle A. From these two sets of measurements, all the Zernike coefficients may be determined for n<N. However, there are usually unknown small rigid body motions of the optic between measurements. Then all the Zernike coefficients for n<N except for piston, tilts, and focus may be determined. We describe the exact mathematical algorithm that does this and describe an interferometer which measures the complete wavefront from pinholes in pinhole aligners. These pinhole aligners are self-contained units which include a fiber optic, focusing optics, and a …
Date: June 29, 2005
Creator: Phillion, D. W.; Sommargren, G. E.; Johnson, M. A.; Decker, T. A.; Taylor, J. S.; Gomie, Y et al.
System: The UNT Digital Library
Impedance and Single Bunch Instability Calculations for the ILCDamping Ring (open access)

Impedance and Single Bunch Instability Calculations for the ILCDamping Ring

An important action item for the damping rings of theInternational Linear Collider (ILC) is to compute the broad-bandimpedance and, from it, the threshold to the microwave instability. Wereport on the status of our study and provide a preliminary estimate ofthe instability threshold based on impedance models developed sofar.
Date: June 29, 2007
Creator: Venturini, Marco; Bane, Karl; Heifets, Sam; Li, Zhenhai; Ng, Cho; Novokhatski, Alexander et al.
System: The UNT Digital Library
[Newspaper article: AIDS, The State of the Science] (open access)

[Newspaper article: AIDS, The State of the Science]

A special report from the Dallas Morning News defining, describing, and providing the history of AIDS.
Date: June 29, 1987
Creator: The Dallas Morning News
System: The UNT Digital Library
A logic flowgraph based concept for decision support and management of nuclear plant operation (open access)

A logic flowgraph based concept for decision support and management of nuclear plant operation

In the US the evolution of automated decision support tools for plant operators has spanned from ''event-oriented'' diagnostic systems to ''symptom-oriented'' computer-based emergency operating procedures. A problem common to both kind of systems is in the initial level of effort required for development of the associated models and software. In the following we will discuss some of the general issues that arise in the development and application of these decision-support systems. We will also propose and discuss an approach founded on the application of an event diagnosis and plant stabilization philosophy. This approach is based on the use of logic flowgraph process-oriented models - arranged in a modular architecture and developed with the aid of an expert-system model builder - as a possible means of achieving the development of an automated and integrated plant management system. This approach should allow the developer to achieve a high process recovery and management capability with a focused and controlled expenditure of development time and resources.
Date: June 29, 1987
Creator: Guarro, S. B.
System: The UNT Digital Library
SOUDAN 2 nuclear decay experiment. Progress report (open access)

SOUDAN 2 nuclear decay experiment. Progress report

Construction of the experiment cavern on the 27th level of the SOUDAN iron mine in northern Minnesota began early this year and will be complete early in 1985. The first 1200 tons of the detector itself is also under construction in the US and UK; installation will begin in mid 1985. Physics exploitation will begin early in 1986 and the first 1200 ton module will be complete early in 1987. The detector may be expanded to between 3 and 5 such modules in the cavern. The detector is an iron tracking calorimeter (rho = 2) consisting of stacks of corrugated steel sheets each 1.2 mm thick. The corrugations form hexagonal channels 1 m long and 16 mm in diameter. A uniform electric field along these channels is provided by the voltage grading arising from the constant standing current in the Hytrel tubes (rho = 2 x 10/sup 12/ ..cap omega.. cm) that line each channel. The tubes are insulated from the steel by sheets of mylar. Ionization in the gas in the tubes drifts in the uniform field to the end of the tube where it is amplified linearly and detected by a matrix of anode wires and cathode strips. …
Date: June 29, 1984
Creator: Minnesota; Argonne; Oxford; Rutherford & Collaboration, Tufts
System: The UNT Digital Library
Electronic excitation and ion source optimization (open access)

Electronic excitation and ion source optimization

The electronic excitation cross sections leading to H/sub 2/(v'') molecules are discussed. The effect of shortening the length of the first chamber of a tandem configuration for the purpose of reducing the atomic concentration is shown to enhance the extracted current density.
Date: June 29, 1987
Creator: Hiskes, J.R. & Lietzke, A.F.
System: The UNT Digital Library
Hydrogeology and hydrodynamics of coral reef pore waters (open access)

Hydrogeology and hydrodynamics of coral reef pore waters

A wide variety of forces can produce head gradients that drive the flow and advective mixing of internal coral reef pore waters. Oscillatory gradients that produce mixing result from wave and tide action. Sustained gradients result from wave and tide-induced setup and ponding, from currents impinging on the reef structure, from groundwater heads, and from density differenced (temperature or salinity gradients). These gradients and the permeabilities and porosities of reef sediments are such that most macropore environments are dominated by advection rather than diffusion. The various driving forces must be analyzed to determine the individual and combined magnitudes of their effects on a specific reef pore-water system. Pore-water movement controls sediment diagenesis, the exchange of nutrients between sediments and benthos, and coastal/island groundwater resources. Because of the complexity of forcing functions, their interactions with specific local reef environments, experimental studies require careful incorporation of these considerations into their design and interpretation. 8 refs., 3 figs., 1 tab.
Date: June 29, 1988
Creator: Buddemeier, R.W. & Oberdorfer, J.A.
System: The UNT Digital Library
Prospects for cellular mutational assays in human populations (open access)

Prospects for cellular mutational assays in human populations

Practical, sensitive, and effective human cellular assays for detecting somatic and germinal mutations would have great value in environmental mutagenesis and carcinogenesis studies. Such assays would fill the void between human mutagenicity and the data that exist from short-term tests and from mutagenicity in other species. This paper discusses the following possible human cellular assays: (1) HPRT (hypoxanthine phosphoribosyltransferase) somatic cell mutation based on 6-thioguanine resistance; (2) hemoglobin somatic cell mutation assay; (3) glycophorin somatic cell mutation assay; and (4) LDH-X sperm cell mutation assay. 18 references.
Date: June 29, 1984
Creator: Mendelsohn, M.L.
System: The UNT Digital Library
Particle distributions in collisionless magnetic reconnection: An implicit Particle-In-Cell (PIC) description (open access)

Particle distributions in collisionless magnetic reconnection: An implicit Particle-In-Cell (PIC) description

Evidence from magnetospheric and solar flare research supports the belief that collisionless magnetic reconnection can proceed on the Alfven-wave crossing timescale. Reconnection behavior that occurs this rapidly in collisionless plasmas is not well understood because underlying mechanisms depend on the details of the ion and electron distributions in the vicinity of the emerging X-points. We use the direct implicit Particle-In-Cell (PIC) code AVANTI to study the details of these distributions as they evolve in the self-consistent E and B fields of magnetic reconnection. We first consider a simple neutral sheet model. We observe rapid movement of the current-carrying electrons away from the emerging X-point. Later in time an oscillation of the trapped magnetic flux is found, superimposed upon continued linear growth due to plasma inflow at the ion sound speed. The addition of a current-aligned and a normal B field widen the scope of our studies.
Date: June 29, 1990
Creator: Hewett, D. W.; Francis, G. E. & Max, C. E.
System: The UNT Digital Library
Semiquantum Chaos and the Large N Expansion (open access)

Semiquantum Chaos and the Large N Expansion

When a classical oscillator is interacting with a purely quantum mechanical oscillator, described by the Lagrangian L = 1/2 x{sup 2} + 1/2A{sup 2} - 1/2 (m{sup 2} + e{sup 2} A{sup 2})x{sup 2}, where A is a classical variable and x is a quantum operator the relevant degrees of freedom for the quantum oscillator when {l_angle}x(t)x(t){r_angle} = G(t). The classical Hamiltonian dynamics governing the variables A(t). {Pi}{sub A}(t). G(t) and {Pi}{sub G}(t) is chaotic so that the results of making measurements on the quantum system at later times are sensitive to initial conditions. We review this system and discuss how this behavior is altered when the quantum fluctuations of the A oscillator are determined exactly and in a 1/N expansion where N is the number of copies of the x oscillator.
Date: June 29, 1994
Creator: Cooper, F.; Habib, S.; Kluger, Y.; Dawson, J.; Meredith, D. & Shepard, H.
System: The UNT Digital Library
Atmospheric transport analysis used in hazard screening methodology (open access)

Atmospheric transport analysis used in hazard screening methodology

Simple, but conservative, atmospheric transport models are used in the initial stages of a hazard screening methodology to determine a preliminary hazard rank. The hazard rank is one indicator of the additional effort, if any, that must be applied to determine if a system is safe. Simple methods avoid prolonged calculations at this early stage when details of potential accidents may be poorly defined. The models are used to simulate the consequences resulting from accidental releases of toxic substances. Instantaneous and constant-rate releases are considered. If a release takes place within a relatively small enclosure, the close-in transport is approximated by assuming the airborne material is instantaneously mixed with the volume of air within this enclosure. For all other situations and large distances, the transport is estimated with simple atmospheric dispersion models using published values of dispersion coefficients for large distances, and values based on turbulent diffusion theory for close-in distances. Consequences are assessed by defining exposure levels that are equivalent to negligible, reversible, and irreversible health effects. The hazard rank is related to the number and location of people within each category of health effects.
Date: June 29, 1992
Creator: Bloom, S. G.
System: The UNT Digital Library
Laser Driven High Pressure, High Strain-Rate Materials Experiments (open access)

Laser Driven High Pressure, High Strain-Rate Materials Experiments

Laser-based experiments are being developed to study the response of solids under high pressure loading. Diagnostic techniques that have been applied include dynamic x-ray diffraction, VISAR wave profile measurements, and post-shock recovery and analysis. These techniques are presented with some results from shocked Si, Al, and Cu experiments.
Date: June 29, 2001
Creator: Kalantar, D. H.; Allen, A. M.; Gregori, F.; Kad, B.; Kumar, M.; Lorenz, K. T. et al.
System: The UNT Digital Library
Smoothed Aggregation Spectral Element Agglomeration AMG: SA-pAMGe (open access)

Smoothed Aggregation Spectral Element Agglomeration AMG: SA-pAMGe

None
Date: June 29, 2011
Creator: Brezina, M & Vassilevski, P S
System: The UNT Digital Library
In situ spectroscopic detection of SMSI effect in a Ni/CeO2 system: hydrogen-induced burial and dig out of metallic nickel (open access)

In situ spectroscopic detection of SMSI effect in a Ni/CeO2 system: hydrogen-induced burial and dig out of metallic nickel

In situ APPES technique demonstrates that the strong metal support interaction effect (SMSI) in the Ni-ceria system is associated with the decoration and burial of metallic particles by the partially reduced support, a phenomenon reversible by evacuation at high temperature of the previously absorbed hydrogen.
Date: June 29, 2010
Creator: Caballero, Alfonso; Holgado, Juan P.; Gonzalez-delaCruz, Victor M.; Habas, Susan e.; Herranz, Tirma & Salmeron, Miquel
System: The UNT Digital Library
Ultrafast Mid-Infrared Intra-Excitonic Response of Individualized Single-Walled Carbon Nanotubes (open access)

Ultrafast Mid-Infrared Intra-Excitonic Response of Individualized Single-Walled Carbon Nanotubes

The quasi-1D confinement and reduced screening of photoexcited charges in single-walled carbon nanotubes (SWNTs) entails strongly-enhanced Coulomb interactions and exciton binding energies. Such amplified electron-hole (e-h) correlations have important implications for both fundamental physics and optoelectronic applications of nanotubes. The availability of"individualized" SWNT ensembles with bright and structured luminescence has rendered specific tube chiralities experimentally accessible. In these samples, evidence for excitonic behavior was found in absorption-luminescence maps, two-photon excited luminescence, or ultrafast carrier dynamics. Here, we report ultrafast mid-infrared (mid-IR) studies of individualized SWNTs, evidencing strong photoinduced absorption around 200 meV in semiconducting tubes of (6,5) and (7,5) chiralities. This manifests the observation of quasi-1D intra-excitonic transitions between different relative-momentum states, in agreement with the binding energy and calculated oscillator strength. Our measurements further reveal a saturation of the photoinduced absorption with increasing phase-space filling of the correlated e-h pairs. The transient mid-IR response represents a new tool, unhindered by restrictions of momentum or interband dipole moment, to investigate the density and dynamics of SWNT excitons.
Date: June 29, 2009
Creator: Wang, Jigang; Graham, Matt W.; Ma, Yingzhong; Fleming, Graham R. & Kaindl, Robert A.
System: The UNT Digital Library
Scenarios for the ATF2 Ultra-Low Betas Proposal (open access)

Scenarios for the ATF2 Ultra-Low Betas Proposal

The current ATF2 Ultra-Low beta proposal was designed to achieve 20nm vertical IP beam size without considering the multipolar components of the FD magnets. In this paper we describe different scenarios that avoid the detrimental effect of these multipolar errors to the beam size at the interaction point (IP). The simplest approach consists in modifying the optics, but other solutions are studied as the introduction of super-conducting wigglers to reduce the emittance or the replacement of the normal-conducting focusing quadrupole in the Final Doublet (NC-QF1FF) with a super-conducting quadrupole one (SC-QF1FF). These are fully addressed in the paper.
Date: June 29, 2012
Creator: Marin, Eduardo; Tomas, Rogelio; Bambade, Philip; Kuroda, Shigeru; Okugi, Toshiyuki; Tauchi, Toshiaki et al.
System: The UNT Digital Library
Sloan Digital Sky Survey Photometric Calibration Revisited (open access)

Sloan Digital Sky Survey Photometric Calibration Revisited

The Sloan Digital Sky Survey calibration is revisited to obtain the most accurate photometric calibration. A small but significant error is found in the flat-fielding of the Photometric telescope used for calibration. Two SDSS star catalogs are compared and the average difference in magnitude as a function of right ascension and declination exhibits small systematic errors in relative calibration. The photometric transformation from the SDSS Photometric Telescope to the 2.5 m telescope is recomputed and compared to synthetic magnitudes computed from measured filter bandpasses.
Date: June 29, 2012
Creator: Marriner, John
System: The UNT Digital Library