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Assessment of Distributed Energy Adoption in Commercial Buildings:Part 1: An Analysis of Policy, Building Loads, Tariff Design, andTechnology Development (open access)

Assessment of Distributed Energy Adoption in Commercial Buildings:Part 1: An Analysis of Policy, Building Loads, Tariff Design, andTechnology Development

Rapidly growing electricity demand brings into question theability of traditional grids to expand correspondingly while providingreliable service. An alternative path is the wider application ofdistributed energy resource (DER) that apply combined heat and power(CHP). It can potentially shave peak loads and satiate its growing thirstfor electricity demand, improve overall energy efficiency, and lowercarbon and other pollutant emissions. This research investigates a methodof choosing economically optimal DER, expanding on prior studies at theBerkeley Lab using the DER design optimization program, the DistributedEnergy Resources Customer Adoption Model (DER-CAM). DER-CAM finds theoptimal combination of installed equipment from available DERtechnologies, given prevailing utility tariffs, site electrical andthermal loads, and a menu of available equipment. It provides a globaloptimization, albeit idealized, that shows how the site energy loads canbe served at minimum cost by selection and operation of on-sitegeneration, heat recovery, and cooling. Utility electricity and gastariffs are key factors determining the economic benefit of a CHPinstallation, however often be neglected. This paper describespreliminary analysis on CHP investment climate in the U.S. and Japan. DERtechnologies, energy prices, and incentive measures has beeninvestigated.
Date: December 31, 2005
Creator: Zhou, Nan; Nishida, Masaru; Gao, Weijun & Marnay, Chris
System: The UNT Digital Library
A Strong Hot Spot Theorem (open access)

A Strong Hot Spot Theorem

A real number alpha is said to be b-normal if every m-long string of digits appears in the base-b expansion of alpha with limiting frequency b-m. We prove that alpha is b-normal if and only if it possesses no base-b ''hot spot''. In other words, alpha is b-normal if and only if there is no real number y such that smaller and smaller neighborhoods of y are visited by the successive shifts of the base-b expansion of alpha with larger and larger frequencies, relative to the lengths of these neighborhoods
Date: December 31, 2005
Creator: Bailey, David H. & Misiurewicz, Michal
System: The UNT Digital Library
Studies of Low-Coordinate Iron Dinitrogen Complexes (open access)

Studies of Low-Coordinate Iron Dinitrogen Complexes

This article discusses low-coordinate iron dinitrogen complexes. Understanding the interaction of N₂ with iron is relevant to the iron catalyst used in the Haber process and to possible roles of the FeMoco active site of nitrogenase.
Date: December 31, 2005
Creator: Smith, Jeremy M.; Sadique, Azwana R.; Cundari, Thomas R., 1964-; Rodgers, Kenton R.; Lukat-Rodgers, Gudrun; Lachicotte, Rene J. et al.
System: The UNT Digital Library
Void Coalescence Processes Quantified through Atomistic and Multiscale Simulation (open access)

Void Coalescence Processes Quantified through Atomistic and Multiscale Simulation

Simulation of ductile fracture at the atomic scale reveals many aspects of the fracture process including specific mechanisms associated with void nucleation and growth as a precursor to fracture and the plastic deformation of the material surrounding the voids and cracks. Recently we have studied void coalescence in ductile metals using large-scale atomistic and continuum simulations. Here we review that work and present some related investigations. The atomistic simulations involve three-dimensional strain-controlled multi-million atom molecular dynamics simulations of copper. The correlated growth of two voids during the coalescence process leading to fracture is investigated, both in terms of its onset and the ensuing dynamical interactions. Void interactions are quantified through the rate of reduction of the distance between the voids, through the correlated directional growth of the voids, and through correlated shape evolution of the voids. The critical inter-void ligament distance marking the onset of coalescence is shown to be approximately one void radius based on the quantification measurements used, independent of the initial separation distance between the voids and the strain-rate of the expansion of the system. No pronounced shear flow is found in the coalescence process.
Date: December 31, 2005
Creator: Rudd, R E; Seppala, E T; Dupuy, L M & Belak, J
System: The UNT Digital Library
Quadrature Rotating-Frame Gradient Fields for Ultra-Low FieldNuclear Magnetic Resonance and Imaging (open access)

Quadrature Rotating-Frame Gradient Fields for Ultra-Low FieldNuclear Magnetic Resonance and Imaging

Magnetic resonance imaging (MRI) in very low fields isfundamentally limited by untruncated concomitant gradients which causesevere distortions in image acquisition and volume selection if thegradient fields are strong compared to the static field. In this paper,it is shown that gradient fields oscillating in quadrature can be usedfor spatial encoding in low fields and provide substantial improvementsover conventional encoding methods using static gradients. In particular,cases where the gradient field is comparable to or higher than theexternal field, Gmax/B0>1, are examined. It is shown thatundistorted slice selection and image encoding is possible because ofsmaller geometric phase errors introduced during cyclic motions of theHamiltonian. In the low field limit (Gmax/B_0 ->infinity) sliceselection is achieved with a combination of soft pulse segments and acoherent train of hard pulses to average out concomitant fields over thefast scale of the rf Hamiltonian.
Date: December 30, 2005
Creator: Bouchard, Louis-Serge
System: The UNT Digital Library
Reducing California's Greenhouse Gas Emissions through ProductLife-Cycle Optimization (open access)

Reducing California's Greenhouse Gas Emissions through ProductLife-Cycle Optimization

Product life-cycle optimization addresses the reduction ofenvironmental burdens associated with the production, use, andend-of-life stages of a product s life cycle. In this paper, we offer anevaluation of the opportunities related to product life-cycleoptimization in California for two key products: personal computers (PCs)and concrete. For each product, we present the results of an explorativecase study to identify specific opportunities for greenhouse gas (GHG)emissions reductions at each stage of the product life cycle. We thenoffer a discussion of the practical policy options that may exist forrealizing the identified GHG reduction opportunities. The case studiesdemonstrate that there may be significant GHG mitigation options as wellas a number of policy options that could lead to life-cycle GHG emissionsreductions for PCs and concrete in California.
Date: December 30, 2005
Creator: Masanet, Eric; Price, Lynn; de la Rue du Can, Stephane & Worrell,Ernst
System: The UNT Digital Library
Deducing the 237U(n,f) cross-section using the Surrogate Ratio Method (open access)

Deducing the 237U(n,f) cross-section using the Surrogate Ratio Method

The authors have deduced the cross section for {sup 237}U(n,f) over an equivalent neutron energy range from 0 to 20 MeV using the Surrogate Ratio method. A 55 MeV {sup 4}He beam from the 88 Inch Cyclotron at Lawrence Berkeley National Laboratory was used to induce fission in the following reactions: {sup 238}U({alpha},{alpha}{prime}f) and {sup 236}U({alpha},{alpha}{prime}f). The {sup 238}U reaction was a surrogate for {sup 237}U(n,f) and the {sup 236}U reaction was used as a surrogate for {sup 235}U(n,f). Scattered alpha particles were detected in a fully depleted segmented silicon telescope array (STARS) over an angle range of 35{sup o} to 60{sup o} with respect to the beam axis. The fission fragments were detected in a third independent silicon detector located at backward angles between 106{sup o} and 131{sup o}.
Date: December 29, 2005
Creator: Burke, J. T.; Bernstein, L. A.; Escher, J.; Ahle, L.; Church, J. A.; Dietrich, F. S. et al.
System: The UNT Digital Library
Kinetics of carboplatin-DNA binding in genomic DNA and bladder cancer cells as determined by accelerator mass spectrometry (open access)

Kinetics of carboplatin-DNA binding in genomic DNA and bladder cancer cells as determined by accelerator mass spectrometry

Cisplatin and carboplatin are platinum-based drugs that are widely used in cancer chemotherapy. The cytotoxicity of these drugs is mediated by platinum-DNA monoadducts and intra- and interstrand diadducts, which are formed following uptake of the drug into the nucleus of cells. The pharmacodynamics of carboplatin display fewer side effects than for cisplatin, albeit with less potency, which may be due to differences in rates of DNA adduct formation. We report the use of accelerator mass spectrometry (AMS), a sensitive detection method often used for radiocarbon quantitation, to measure both the kinetics of [{sup 14}C]carboplatin-DNA adduct formation with genomic DNA and drug uptake and DNA binding in T24 human bladder cancer cells. Only carboplatin-DNA monoadducts contain radiocarbon in the platinated DNA, which allowed for calculation of kinetic rates and concentrations within the system. The percent of radiocarbon bound to salmon sperm DNA in the form of monoadducts was measured by AMS over 24 h. Knowledge of both the starting concentration of the parent carboplatin and the concentration of radiocarbon in the DNA at a variety of time points allowed calculation of the rates of Pt-DNA monoadduct formation and conversion to toxic cross-links. Importantly, the rate of carboplatin-DNA monoadduct formation was approximately …
Date: December 29, 2005
Creator: Hah, S S; Stivers, K M; Vere White, R & Henderson, P T
System: The UNT Digital Library
The complete mitochondrial genome of the enigmatic bigheadedturtle (Platysternon): description of unusual genomic features and there conciliation of phylogenetic hypotheses based on mitochondrial and nuclear DNA (open access)

The complete mitochondrial genome of the enigmatic bigheadedturtle (Platysternon): description of unusual genomic features and there conciliation of phylogenetic hypotheses based on mitochondrial and nuclear DNA

The big-headed turtle (Platysternon megacephalum) from east Asia is the sole living representative of a poorly-studied turtle lineage (Platysternidae). It has no close living relatives, and its phylogenetic position within turtles is one of the outstanding controversies in turtle systematics. Platysternon was traditionally considered to be close to snapping turtles (Chelydridae) based on some studies of its morphology and mitochondrial (mt) DNA, however, other studies of morphology and nuclear (nu) DNA do not support that hypothesis. We sequenced the complete mt genome of Platysternon and the nearly complete mt genomes of two other relevant turtles and compared them to turtle mt genomes from the literature to form the largest molecular dataset used to date to address this issue. The resulting phylogeny robustly rejects the placement of Platysternon with Chelydridae, but instead shows that it is a member of the Testudinoidea, a diverse, nearly globally-distributed group that includes pond turtles and tortoises. We also discovered that Platysternon mtDNA has large-scale gene rearrangements and possesses two, nearly identical, control regions, features that distinguish it from all other studied turtles. Our study robustly determines the phylogenetic placement of Platysternon and provides a well-resolved outline of major turtle lineages, while demonstrating the significantly greater …
Date: December 28, 2005
Creator: Parham, James F.; Feldman, Chris R. & Boore, Jeffrey L.
System: The UNT Digital Library
U-Sr isotopic speedometer: Fluid flow and chemical weatheringrates inaquifers (open access)

U-Sr isotopic speedometer: Fluid flow and chemical weatheringrates inaquifers

Both chemical weathering rates and fluid flow are difficultto measure in natural systems. However, these parameters are critical forunderstanding the hydrochemical evolution of aquifers, predicting thefate and transport of contaminants, and for water resources/water qualityconsiderations. 87Sr/86Sr and (234U/238U) activity ratios are sensitiveindicators of water-rock interaction, and thus provide a means ofquantifying both flow and reactivity. The 87Sr/86Sr values in groundwaters are controlled by the ratio of the dissolution rate to the flowrate. Similarly, the (234U/238U) ratio of natural ground waters is abalance between the flow rate and the dissolution of solids, andalpha-recoil loss of 234U from the solids. By coupling these two isotopesystems it is possible to constrain both the long-term (ca. 100's to1000's of years) flow rate and bulk dissolution rate along the flow path.Previous estimates of the ratio of the dissolution rate to theinfiltration flux from Sr isotopes (87Sr/86Sr) are combined with a modelfor (234U/238U) to constrain the infiltration flux and dissolution ratefor a 70-m deep vadose zone core from Hanford, Washington. The coupledmodel for both (234U/238U) ratios and the 87Sr/86Sr data suggests aninfiltration flux of 5+-2 mm/yr, and bulk silicate dissolution ratesbetween 10-15.7 and 10-16.5 mol/m2/s. The process of alpha-recoilenrichment, while primarily responsible for the observed variation …
Date: December 27, 2005
Creator: Maher, Kate; DePaolo, Donald J. & Christensen, John N.
System: The UNT Digital Library
Quantum efficiency characterization of LBNL CCD's Part 1: theQuantum Efficiency Machine (open access)

Quantum efficiency characterization of LBNL CCD's Part 1: theQuantum Efficiency Machine

Instrumentation was developed in 2004 and 2005 to measurethe quantum efficiency of the Lawrence Berkeley National Lab(LBNL)total-depletion CCD's, intended for astronomy and spaceapplications. This paper describes the basic instrument. Although it isconventional even to the parts list, there are important innovations. Axenon arc light source was chosen for its high blue/UV and low red/IRoutput as compared with a tungsten light. Intensity stabilization hasbeen difficult, but sinceonly flux ratios matter this is not critical.Between the light source andan Oriel MS257 monochromator are a shutterand two filter wheels. High-bandpass and low-bandpass filter pairsisolate the 150-nm wide bands appropriate to the wavelength, thusminimizing scattered light and providing order blocking. Light from theauxiliary port enters a 20-inch optical sphere, and the 4-inch outputport is at right angles to the input port. An 80 cm drift space producesnear-uniform illumination on the CCD. Next to the cold CCD inside thehorizontal dewar is a calibrated reference photodiode which is regulatedto the PD calibration temperature, 25$^\circ$ C. The ratio ofthe CCD andin-dewar reference PD signals provides the QE measurement. Additionalcross-calibration to a PD on the integrating spherepermitslower-intensity exposures.
Date: December 25, 2005
Creator: Groom, Donald E.; Bebek, Christopher J.; Fabricius, Maximilian; Karcher, Armin; Kolbe, William F.; Roe, Natalie A. et al.
System: The UNT Digital Library
Linear and nonlinear Rayleigh-Taylor growth at strongly convergent spherical interfaces (open access)

Linear and nonlinear Rayleigh-Taylor growth at strongly convergent spherical interfaces

Recent attention has focused on the effect of spherical convergence on the nonlinear phase of Rayleigh-Taylor growth. For instability growth on spherically converging interfaces, modifications to the predictions of the Layzer model for the secular growth of a single, nonlinear mode have been reported [D. S. Clark and M. Tabak, Phys. Rev. E 72, 0056308 (2005).]. However, this model is limited in assuming a self-similar background implosion history as well as only addressing growth from a perturbation of already nonlinearly large amplitude. Additionally, only the case of single-mode growth was considered and not the multimode growth of interest in applications. Here, these deficiencies are remedied. First, the connection of the recent nonlinear results including convergence to the well-known results for the linear regime of growth is demonstrated. Second, the applicability of the model to more general implosion histories (i.e., not self-similar) is shown. Finally, to address the case of multimode growth with convergence, the recent nonlinear single mode results are combined with the Haan model formulation for weakly nonlinear multimode growth. Remarkably, convergence in the nonlinear regime is found not to modify substantially the multimode predictions of Haan's original model.
Date: December 22, 2005
Creator: Clark, D S & Tabak, M
System: The UNT Digital Library
Material-dependent high-frequency current fluctuations of cathodicvacuum arcs: Evidence for the ecton cutoff of the fractal model (open access)

Material-dependent high-frequency current fluctuations of cathodicvacuum arcs: Evidence for the ecton cutoff of the fractal model

Current fluctuations of cathodic arcs were recorded withhigh analog bandwidth (up to 1 GHz) and fast digital sampling (up to 5Gsamples/sec). The power spectral density of the arc current wasdetermined by fast Fourier transform clearly showing material dependent,non-linear features in the frequency domain. These features can beassociated with the non-linear impedance of the conducting channelbetween cathode and anode, driven by the explosive nature of electronemission and plasma formation. The characteristic times of less than 100ns can be associated with individual explosive processes, "ectons," andtherefore represent the short-time physical cutoff for the fractal modelof cathodic arcs.
Date: December 22, 2005
Creator: Anders, Andre & Oks, Efim
System: The UNT Digital Library
Relativistic multireference many-body perturbation theory calculations on F-, Ne-, Na-, Mg-, Al-, Si-, and P-like xenon ions (open access)

Relativistic multireference many-body perturbation theory calculations on F-, Ne-, Na-, Mg-, Al-, Si-, and P-like xenon ions

Many-Body Perturbation Theory (MBPT) has been employed to calculate with high wavelength accuracy the extreme ultraviolet (EUV) spectra of F-like to P-like Xe ions. They discuss the reliability of the new calculations using the example of EUV beam-foil spectra of Xe, in which n = 3, {Delta}n = 0 transitions of Na-, Mg-, Al-like, and Si-like ions have been found to dominate. A further comparison is made with spectra from an electron beam ion trap, that is, from a device with a very different (low density) excitation balance.
Date: December 22, 2005
Creator: Vilkas, M J; Ishikawa, Y & Trabert, E
System: The UNT Digital Library
ANDY: A general, fault-tolerant tool for database searching oncomputer clusters (open access)

ANDY: A general, fault-tolerant tool for database searching oncomputer clusters

Summary: ANDY (seArch coordination aND analYsis) is a set ofPerl programs and modules for distributing large biological databasesearches, and in general any sequence of commands, across the nodes of aLinux computer cluster. ANDY is compatible with several commonly usedDistributed Resource Management (DRM) systems, and it can be easilyextended to new DRMs. A distinctive feature of ANDY is the choice ofeither dedicated or fair-use operation: ANDY is almost as efficient assingle-purpose tools that require a dedicated cluster, but it runs on ageneral-purpose cluster along with any other jobs scheduled by a DRM.Other features include communication through named pipes for performance,flexible customizable routines for error-checking and summarizingresults, and multiple fault-tolerance mechanisms. Availability: ANDY isfreely available and may be obtained fromhttp://compbio.berkeley.edu/proj/andy; this site also containssupplemental data and figures and amore detailed overview of thesoftware.
Date: December 21, 2005
Creator: Smith, Andrew; Chandonia, John-Marc & Brenner, Steven E.
System: The UNT Digital Library
Commentary on John Gibbs' "What Do Near-Death Experiencers and Jesus Have in Common? The Near-Death Experience and Spong's New New Christianity" (open access)

Commentary on John Gibbs' "What Do Near-Death Experiencers and Jesus Have in Common? The Near-Death Experience and Spong's New New Christianity"

Abstract: John Gibbs relates research findings on near-death experiences (NDEs) to John Shelby Spong's "continuity view of Jesus" and his "call for a new Christianity." Gibbs' argument falls short of demonstrating congruence of the scientific findings of NDE research with the theological claims of Spong, who posits that Jesus was not God, but just a person.
Date: Winter 2005
Creator: Sabom, Michael B.
System: The UNT Digital Library
Designing a multi-petabyte database for LSST (open access)

Designing a multi-petabyte database for LSST

The 3.2 giga-pixel LSST camera will produce over half a petabyte of raw images every month. This data needs to be reduced in under a minute to produce real-time transient alerts, and then cataloged and indexed to allow efficient access and simplify further analysis. The indexed catalogs alone are expected to grow at a speed of about 600 terabytes per year. The sheer volume of data, the real-time transient alerting requirements of the LSST, and its spatio-temporal aspects require cutting-edge techniques to build an efficient data access system at reasonable cost. As currently envisioned, the system will rely on a database for catalogs and metadata. Several database systems are being evaluated to understand how they will scale and perform at these data volumes in anticipated LSST access patterns. This paper describes the LSST requirements, the challenges they impose, the data access philosophy, and the database architecture that is expected to be adopted in order to meet the data challenges.
Date: December 21, 2005
Creator: Becla, J & Hanushevsky, A
System: The UNT Digital Library
Evidence for p-type doping of InN (open access)

Evidence for p-type doping of InN

None
Date: December 21, 2005
Creator: Jones, R. E.; Yu, K. M.; Li, S. X.; Walukiewicz, W.; Ager, J. W., III; Haller, E. E. et al.
System: The UNT Digital Library
Fermi Surface Nesting and Pre-Martensitic Softening in V and Nb at High Pressures (open access)

Fermi Surface Nesting and Pre-Martensitic Softening in V and Nb at High Pressures

First-principles total-energy calculations were performed for the trigonal shear elastic constant (C{sub 44}) of vanadium and niobium. A mechanical instability in C{sub 44} is found for vanadium at pressures {approx} 2 Mbar which also shows softening in niobium at pressures {approx} 0.5 Mbar. We argue that the pressure-induced shear instability (softening) of vanadium (niobium) is due to the intraband nesting of the Fermi surface.
Date: December 21, 2005
Creator: Landa, A; Klepeis, J; Soderlind, P; Naumov, I; Velikokhatnyi, O; Vitos, L et al.
System: The UNT Digital Library
The Impact of Structural Genomics: Expectations and Outcomes (open access)

The Impact of Structural Genomics: Expectations and Outcomes

Structural Genomics (SG) projects aim to expand our structural knowledge of biological macromolecules, while lowering the average costs of structure determination. We quantitatively analyzed the novelty, cost, and impact of structures solved by SG centers, and contrast these results with traditional structural biology. The first structure from a protein family is particularly important to reveal the fold and ancient relationships to other proteins. In the last year, approximately half of such structures were solved at a SG center rather than in a traditional laboratory. Furthermore, the cost of solving a structure at the most efficient U.S. center has now dropped to one-quarter the estimated cost of solving a structure by traditional methods. However, top structural biology laboratories are much more efficient than the average, and comparable to SG centers despite working on very challenging structures. Moreover, traditional structural biology papers are cited significantly more often, suggesting greater current impact.
Date: December 21, 2005
Creator: Chandonia, John-Marc & Brenner, Steven E.
System: The UNT Digital Library
Measurement of the CKM Angle alpha with the B-factories. (open access)

Measurement of the CKM Angle alpha with the B-factories.

B-meson decays involving b {yields} u transitions are sensitive to the Unitarity Triangle angle {alpha} (or {phi}{sub 2}). The B-factories at SLAC and KEK have made significant progress toward the measurement of {alpha} in recent years. This paper summarizes the results of the B-factories' constraints on {alpha}.
Date: December 21, 2005
Creator: Bevan, Adrian
System: The UNT Digital Library
Prevalence of Near-Death Experiences in Australia (open access)

Prevalence of Near-Death Experiences in Australia

Study assessing the prevalence of near-death experiences (NDEs) in Australia through the use of questionnaires.
Date: Winter 2005
Creator: Perera, Mahendra; Padmasekara, Gayan & Belanti, John
System: The UNT Digital Library
Radium-226 and low pH in groundwater due to oxidation of authigenic pyrite; Savannah River Site, South Carolina (open access)

Radium-226 and low pH in groundwater due to oxidation of authigenic pyrite; Savannah River Site, South Carolina

The origin of elevated radium-226 in groundwater beneath a sanitary landfill at the Savannah River Site (SRS) was investigated. Nearly one hundred monitoring wells are developed in the Steed Pond Aquifer (SPA), which consists of 100-150 ft of Coastal Plain sand, iron oxides, and minor clay. Wells screened in the upper and middle portions of the aquifer have average Ra-226 between 0.5 and 2.5 pCi/L, and average pHs above 4.7. However, wells screened near the base of the aquifer exhibit higher average Ra-226 concentrations of 2.5 to 4.6 pCi/L, with some measurements exceeding the MCL of 5 pCi/L, and show average pHs of 4.1 to 4.7. These wells are not downgradient of the landfill, and are not impacted by landfill leachate. The Crouch Branch Confining Unit (CBCU) underlies the aquifer, and is composed partly of reduced gray/brown clay with lignite and authigenic pyrite. Gamma ray logs show that the SPA has low gamma counts, but the CBCU is consistently elevated. Groundwater with high radium/low pH also contains elevated sulfate concentrations. pH calculations indicate that sulfate is in the form of sulfuric acid. A model for the origin of elevated Ra-226 levels in deeper SPA wells envisions infiltration of oxygenated SPA …
Date: December 21, 2005
Creator: Kubilius, Walter & Ross, Jeffrey
System: The UNT Digital Library
Rediscovery of the Elements: Paracelsus (open access)

Rediscovery of the Elements: Paracelsus

Article describing the career and discoveries of Phillippus Aureolus Theophrastus Paracelsus Bombastus von Hohenheim. Tourist information regarding locations important to his life are visited and discussed.
Date: Winter 2005
Creator: Marshall, James L., 1940- & Marshall, Virginia R.
System: The UNT Digital Library