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Design of District Emergency Operations Centres, and the Case Study of Indian Oil Corporation Jaipur Depot Explosion (open access)

Design of District Emergency Operations Centres, and the Case Study of Indian Oil Corporation Jaipur Depot Explosion

Article on the design of district emergency operations centres and a case study of Indian Oil Corporation Jaipur depot explosion.
Date: November 22, 2010
Creator: Gupta, Kailash
System: The UNT Digital Library
Long-range surface plasmons in dielectric-metal-dielectric structure with highly anisotropic substrates (open access)

Long-range surface plasmons in dielectric-metal-dielectric structure with highly anisotropic substrates

This article discusses long-range surface plasmons in dielectric-metal-dielectric structure with highly anisotropic substrates.
Date: February 22, 2010
Creator: Nagaraj & Krokhin, Arkadii A.
System: The UNT Digital Library
A Two-Coordinate Nickel Imido Complex That Effects C-H Amination (open access)

A Two-Coordinate Nickel Imido Complex That Effects C-H Amination

This article discusses a two-coordinate nickel imido complex that effects C-H amination.
Date: December 22, 2010
Creator: Laskowski, Carl A.; Miller, Alexander J.M.; Hillhouse, Gregory L. & Cundari, Thomas R., 1964-
System: The UNT Digital Library
Text and Structural Data Mining of Influenza Mentions in Web and Social Media (open access)

Text and Structural Data Mining of Influenza Mentions in Web and Social Media

This article discusses text and structural data mining of influenza mentions in web and social media.
Date: February 22, 2010
Creator: Corley, Courtney; Cook, Diane J., 1963-; Mikler, Armin R. & Singh, Karan P.
System: The UNT Digital Library
Co-Simulation of Building Energy and Control Systems with the Building Controls Virtual Test Bed (open access)

Co-Simulation of Building Energy and Control Systems with the Building Controls Virtual Test Bed

This article describes the implementation of the Building Controls Virtual Test Bed (BCVTB). The BCVTB is a software environment that allows connecting different simulation programs to exchange data during the time integration, and that allows conducting hardware in the loop simulation. The software architecture is a modular design based on Ptolemy II, a software environment for design and analysis of heterogeneous systems. Ptolemy II provides a graphical model building environment, synchronizes the exchanged data and visualizes the system evolution during run-time. The BCVTB provides additions to Ptolemy II that allow the run-time coupling of different simulation programs for data exchange, including EnergyPlus, MATLAB, Simulink and the Modelica modelling and simulation environment Dymola. The additions also allow executing system commands, such as a script that executes a Radiance simulation. In this article, the software architecture is presented and the mathematical model used to implement the co-simulation is discussed. The simulation program interface that the BCVTB provides is explained. The article concludes by presenting applications in which different state of the art simulation programs are linked for run-time data exchange. This link allows the use of the simulation program that is best suited for the particular problem to model building heat transfer, …
Date: August 22, 2010
Creator: Wetter, Michael
System: The UNT Digital Library
Photodetectors for Scintillator Proportionality Measurement (open access)

Photodetectors for Scintillator Proportionality Measurement

None
Date: October 22, 2010
Creator: Moses, William W.; Choong, W. -S.; Hull, G.; Payne, S.; Cherepy, N. & Valentine, J. D.
System: The UNT Digital Library
Enhanced Magnetism of Fe3O4 Nanoparticles with Ga Doping (open access)

Enhanced Magnetism of Fe3O4 Nanoparticles with Ga Doping

Magnetic (Ga{sub x}Fe{sub 1-x}){sub 3}O{sub 4} nanoparticles with 5%-33% gallium doping (x = 0.05-0.33) were measured using x-ray absorption spectroscopy and x-ray magnetic circular dichroism to determine that the Ga dopant is substituting for Fe{sub 3+} as Ga{sub 3+} in the tetrahedral A-site of the spinel structure, resulting in an overall increase in the total moment of the material. Frequency-dependent alternating-current magnetic susceptibility measurements showed these particles to be weakly interacting with a reduction of the cubic anisotropy energy term with Ga concentration. The element-specific dichroism spectra show that the average Fe moment is observed to increase with Ga concentration, a result consistent with the replacement of A-site Fe by Ga.
Date: October 22, 2010
Creator: Pool, V. L.; Klem, M. T.; Chorney, C. L.; Arenholz, E. & Idzerda, Y.U.
System: The UNT Digital Library
From many body wee partons dynamics to perfect fluid: a standard model for heavy ion collisions (open access)

From many body wee partons dynamics to perfect fluid: a standard model for heavy ion collisions

We discuss a standard model of heavy ion collisions that has emerged both from experimental results of the RHIC program and associated theoretical developments. We comment briefly on the impact of early results of the LHC program on this picture. We consider how this standard model of heavy ion collisions could be solidified or falsified in future experiments at RHIC, the LHC and a future Electro-Ion Collider.
Date: July 22, 2010
Creator: Venugopalan, R.
System: The UNT Digital Library
Analysis of the National Ignition Facility Ignition Hohlraum Energetics Experiments (open access)

Analysis of the National Ignition Facility Ignition Hohlraum Energetics Experiments

A series of forty experiments on the National Ignition Facility (NIF) [E. I. Moses et al., Phys. Plasmas 16, 041006 (2009)] to study energy balance and implosion symmetry in reduced- and full-scale ignition hohlraums was shot at energies up to 1.3 MJ. This paper reports the findings of the analysis of the ensemble of experimental data obtained that has produced an improved model for simulating ignition hohlraums. Last year the first observation in a NIF hohlraum of energy transfer between cones of beams as a function of wavelength shift between those cones was reported [P. Michel, et al, Phys of Plasmas, 17, 056305, (2010)]. Detailed analysis of hohlraum wall emission as measured through the laser entrance hole (LEH) has allowed the amount of energy transferred versus wavelength shift to be quantified. The change in outer beam brightness is found to be quantitatively consistent with LASNEX [G. B. Zimmerman and W. L. Kruer, Comments Plasma Phys. Control. Fusion 2, 51 (1975)] simulations using the predicted energy transfer when possible saturation of the plasma wave mediating the transfer is included. The effect of the predicted energy transfer on implosion symmetry is also found to be in good agreement with gated x-ray framing …
Date: November 22, 2010
Creator: Town, R. J.; Rosen, M. D.; Michel, P. A.; Divol, L.; Moody, J. D.; Kyrala, G. A. et al.
System: The UNT Digital Library
A molecularly defined duplication set for the X chromosome of Drosophila melanogaster (open access)

A molecularly defined duplication set for the X chromosome of Drosophila melanogaster

We describe a molecularly defined duplication kit for the X chromosome of Drosophila melanogaster. A set of 408 overlapping P[acman] BAC clones was used to create small duplications (average length 88 kb) covering the 22-Mb sequenced portion of the chromosome. The BAC clones were inserted into an attP docking site on chromosome 3L using C31 integrase, allowing direct comparison of different transgenes. The insertions complement 92% of the essential and viable mutations and deletions tested, demonstrating that almost all Drosophila genes are compact and that the current annotations of the genome are reasonably accurate. Moreover, almost all genes are tolerated at twice the normal dosage. Finally, we more precisely mapped two regions at which duplications cause diplo-lethality in males. This collection comprises the first molecularly defined duplication set to cover a whole chromosome in a multicellular organism. The work presented removes a long-standing barrier to genetic analysis of the Drosophila X chromosome, will greatly facilitate functional assays of X-linked genes in vivo, and provides a model for functional analyses of entire chromosomes in other species.
Date: July 22, 2010
Creator: Venken, Koen J. T.; Popodi, Ellen; Holtzman, Stacy L.; Schulze, Karen L.; Park, Soo; Carlson, Joseph W. et al.
System: The UNT Digital Library
A Proposal for User-defined Reductions in OpenMP (open access)

A Proposal for User-defined Reductions in OpenMP

Reductions are commonly used in parallel programs to produce a global result from partial results computed in parallel. Currently, OpenMP only supports reductions for primitive data types and a limited set of base language operators. This is a significant limitation for those applications that employ user-defined data types (e. g., objects). Implementing manual reduction algorithms makes software development more complex and error-prone. Additionally, an OpenMP runtime system cannot optimize a manual reduction algorithm in ways typically applied to reductions on primitive types. In this paper, we propose new mechanisms to allow the use of most pre-existing binary functions on user-defined data types as User-Defined Reduction (UDR) operators. Our measurements show that our UDR prototype implementation provides consistently good performance across a range of thread counts without increasing general runtime overheads.
Date: March 22, 2010
Creator: Duran, A; Ferrer, R; Klemm, M; de Supinski, B R & Ayguade, E
System: The UNT Digital Library
A Piecewise Bi-Linear Discontinuous Finite Element Spatial Discretization of the Sn Transport Equation (open access)

A Piecewise Bi-Linear Discontinuous Finite Element Spatial Discretization of the Sn Transport Equation

We present a new spatial discretization of the discrete-ordinates transport equation in two-dimensional Cartesian (X-Y) geometry for arbitrary polygonal meshes. The discretization is a discontinuous finite element method (DFEM) that utilizes piecewise bi-linear (PWBL) basis functions, which are formally introduced in this paper. We also present a series of numerical results on quadrilateral and polygonal grids and compare these results to a variety of other spatial discretizations that have been shown to be successful on these grid types. Finally, we note that the properties of the PWBL basis functions are such that the leading-order piecewise bi-linear discontinuous finite element (PWBLD) solution will satisfy a reasonably accurate diffusion discretization in the thick diffusion limit, making the PWBLD method a viable candidate for many different classes of transport problems.
Date: December 22, 2010
Creator: Bailey, T S; Chang, J H; Warsa, J S & Adams, M L
System: The UNT Digital Library
The Influence of Linker Geometry on Uranyl Complexation by Rigidly-Linked Bis(3-hydroxy-N-methyl-pyridin-2-one) (open access)

The Influence of Linker Geometry on Uranyl Complexation by Rigidly-Linked Bis(3-hydroxy-N-methyl-pyridin-2-one)

A series of bis(3-hydroxy-N-methyl-pyridin-2-one) ligands was synthesized, and their respective uranyl complexes were characterized by single crystal X-ray diffraction analyses. These structures were inspected for high-energy conformations and evaluated using a series of metrics to measure co-planarity of chelating moieties with each other and the uranyl coordination plane, as well as to measure coordinative crowding about the uranyl dication. Both very short (ethyl, 3,4-thiophene and o-phenylene) and very long ({alpha},{alpha}{prime}-m-xylene and 1,8-fluorene) linkers provide optimal ligand geometries about the uranyl cation, resulting in planar, unstrained molecular arrangements. The planarity of the rigid linkers also suggests there is a degree of pre-organization for a planar coordination mode that is ideal for uranyl-selective ligand design. Comparison of intramolecular N{sub amide}-O{sub phenolate} distances and {sup 1}H NMR chemical shifts of amide protons supports earlier results that short linkers provide the optimal geometry for intramolecular hydrogen bonding.
Date: April 22, 2010
Creator: Szigethy, Geza & Raymond, Kenneth
System: The UNT Digital Library
Epithermal Neutron Source for Neutron Resonance Spectroscopy (NRS) using High Intensity, Short Pulse Lasers (open access)

Epithermal Neutron Source for Neutron Resonance Spectroscopy (NRS) using High Intensity, Short Pulse Lasers

A neutron source for neutron resonance spectroscopy (NRS) has been developed using high intensity, short pulse lasers. This measurement technique will allow for robust measurements of interior ion temperature of laser-shocked materials and provide insight into equation of state (EOS) measurements. The neutron generation technique uses protons accelerated by lasers off of Cu foils to create neutrons in LiF, through (p,n) reactions with {sup 7}Li and {sup 19}F. The distribution of the incident proton beam has been diagnosed using radiochromic film (RCF). This distribution is used as the input for a (p,n) neturon prediction code which is compared to experimentally measured neutron yields. From this calculation, a total fluence of 1.8 x 10{sup 9} neutrons is infered, which is shown to be a reasonable amount for NRS temperature measurement.
Date: April 22, 2010
Creator: Higginson, D. P.; McNaney, J. M.; Swift, D. C.; Bartal, T.; Hey, D. S.; Pape, S. L. et al.
System: The UNT Digital Library
Thin Silicon MEMS Contact-Stress Sensor (open access)

Thin Silicon MEMS Contact-Stress Sensor

This thin, MEMS contact-stress (CS) sensor continuously and accurately measures time-varying, solid interface loads in embedded systems over tens of thousands of load cycles. Unlike all other interface load sensors, the CS sensor is extremely thin (< 150 {micro}m), provides accurate, high-speed measurements, and exhibits good stability over time with no loss of calibration with load cycling. The silicon CS sensor, 5 mm{sup 2} and 65 {micro}m thick, has piezoresistive traces doped within a load-sensitive diaphragm. The novel package utilizes several layers of flexible polyimide to mechanically and electrically isolate the sensor from the environment, transmit normal applied loads to the diaphragm, and maintain uniform thickness. The CS sensors have a highly linear output in the load range tested (0-2.4 MPa) with an average accuracy of {+-} 1.5%.
Date: March 22, 2010
Creator: Kotovsky, J; Tooker, A & Horsley, D
System: The UNT Digital Library
Persistence of gamma-H2AX and 53BP1 foci in proliferating and nonproliferating human mammary epithelial cells after exposure to gamma-rays or iron ions (open access)

Persistence of gamma-H2AX and 53BP1 foci in proliferating and nonproliferating human mammary epithelial cells after exposure to gamma-rays or iron ions

To investigate {gamma}-H2AX (phosphorylated histone H2AX) and 53BP1 (tumour protein 53 binding protein No. 1) foci formation and removal in proliferating and non-proliferating human mammary epithelial cells (HMEC) after exposure to sparsely and densely ionizing radiation under different cell culture conditions. HMEC cells were grown either as monolayers (2D) or in extracellular matrix to allow the formation of acinar structures in vitro (3D). Foci numbers were quantified by image analysis at various time points after exposure. Our results reveal that in non-proliferating cells under 2D and 3D cell culture conditions, iron-ion induced {gamma}-H2AX foci were still present at 72 h after exposure, although 53BP1 foci returned to control levels at 48 h. In contrast in proliferating HMEC, both {gamma}-H2AX and 53BP1 foci decreased to control levels during the 24-48 h time interval after irradiation under 2D conditions. Foci numbers decreased faster after {gamma}-ray irradiation and returned to control levels by 12 h regardless of marker, cell proliferation status, and cell culture condition. Conclusions: The disappearance of radiation induced {gamma}-H2AX and 53BP1 foci in HMEC have different dynamics that depend on radiation quality and proliferation status. Notably, the general patterns do not depend on the cell culture condition (2D versus 3D). …
Date: December 22, 2010
Creator: Groesser, Torsten; Chang, Hang; Fontenay, Gerald; Chen, James; Costes, Sylvain V.; Barcellos-Hoff, Mary Helen et al.
System: The UNT Digital Library
Identification of functional elements and regulatory circuits by Drosophila modENCODE (open access)

Identification of functional elements and regulatory circuits by Drosophila modENCODE

To gain insight into how genomic information is translated into cellular and developmental programs, the Drosophila model organism Encyclopedia of DNA Elements (modENCODE) project is comprehensively mapping transcripts, histone modifications, chromosomal proteins, transcription factors, replication proteins and intermediates, and nucleosome properties across a developmental time course and in multiple cell lines. We have generated more than 700 data sets and discovered protein-coding, noncoding, RNA regulatory, replication, and chromatin elements, more than tripling the annotated portion of the Drosophila genome. Correlated activity patterns of these elements reveal a functional regulatory network, which predicts putative new functions for genes, reveals stage- and tissue-specific regulators, and enables gene-expression prediction. Our results provide a foundation for directed experimental and computational studies in Drosophila and related species and also a model for systematic data integration toward comprehensive genomic and functional annotation. Several years after the complete genetic sequencing of many species, it is still unclear how to translate genomic information into a functional map of cellular and developmental programs. The Encyclopedia of DNA Elements (ENCODE) (1) and model organism ENCODE (modENCODE) (2) projects use diverse genomic assays to comprehensively annotate the Homo sapiens (human), Drosophila melanogaster (fruit fly), and Caenorhabditis elegans (worm) genomes, through systematic …
Date: December 22, 2010
Creator: Roy, Sushmita; Ernst, Jason; Kharchenko, Peter V.; Kheradpour, Pouya; Negre, Nicolas; Eaton, Matthew L. et al.
System: The UNT Digital Library
Orbital Moment Determination in (MnxFe1-x)3O4 Nanoparticles (open access)

Orbital Moment Determination in (MnxFe1-x)3O4 Nanoparticles

Nanoparticles of (Mn{sub x}Fe{sub 1-x}){sub 3}O{sub 4} with a concentration ranging from x = 0 to 1 and a crystallite size of 14-15 nm were measured using X-ray absorption spectroscopy and X-ray magnetic circular dichroism to determine the ratio of the orbital moment to the spin moment for Mn and Fe. At low Mn concentrations, the Mn substitutes into the host Fe{sub 3}O{sub 4} spinel structure as Mn{sup 2+} in the tetrahedral A-site. The net Fe moment, as identified by the X-ray dichroism intensity, is found to increase at the lowest Mn concentrations then rapidly decrease until no dichroism is observed at 20% Mn. The average Fe orbit/spin moment ratio is determined to initially be negative and small for pure Fe{sub 3}O{sub 4} nanoparticles and quickly go to 0 by 5%-10% Mn addition. The average Mn moment is anti-aligned to the Fe moment with an orbit/spin moment ratio of 0.12 which gradually decreases with Mn concentration.
Date: October 22, 2010
Creator: Pool, V. L.; Jolley, C.; Douglas, T.; Arenholz, E. & Idzerda, Y. U.
System: The UNT Digital Library
Planning Tools for Estimating Radiation Exposure at the National Ignition Facility (open access)

Planning Tools for Estimating Radiation Exposure at the National Ignition Facility

A set of computational tools was developed to help estimate and minimize potential radiation exposure to workers from material activation in the National Ignition Facility (NIF). AAMI (Automated ALARA-MCNP Interface) provides an efficient, automated mechanism to perform the series of calculations required to create dose rate maps for the entire facility with minimal manual user input. NEET (NIF Exposure Estimation Tool) is a web application that combines the information computed by AAMI with a given shot schedule to compute and display the dose rate maps as a function of time. AAMI and NEET are currently used as work planning tools to determine stay-out times for workers following a given shot or set of shots, and to help in estimating integrated doses associated with performing various maintenance activities inside the target bay. Dose rate maps of the target bay were generated following a low-yield 10{sup 16} D-T shot and will be presented in this paper.
Date: October 22, 2010
Creator: Verbeke, J.; Young, M.; Brereton, S.; Dauffy, L.; Hall, J.; Hansen, L. et al.
System: The UNT Digital Library
New Superheavy Element Isotopes: 242Pu(48Ca,5n)285114 (open access)

New Superheavy Element Isotopes: 242Pu(48Ca,5n)285114

The new, neutron-deficient, superheavy element isotope {sup 285}114 was produced in {sup 48}Ca irradiations of {sup 242}Pu targets at a center-of-target beam energy of 256 MeV (E* = 50 MeV). The {alpha} decay of {sup 285}114 was followed by the sequential {alpha} decay of four daughter nuclides, {sup 281}Cn, {sup 277}Ds, {sup 273}Hs, and {sup 269}Sg. {sup 265}Rf was observed to decay by spontaneous fission. The measured {alpha}-decay Q values were compared with those from a macroscopic-microscopic nuclear mass model to give insight into superheavy element shell effects. The {sup 242}Pu({sup 48}Ca,5n){sup 285}114 cross section was 0.6{sub -0.5}{sup +0.9} pb.
Date: October 22, 2010
Creator: Ellison, Paul A; Gregorich, Kenneth E.; Berryman, Jill S.; Bleuel, Darren L.; Clark, Roderick M.; Dragojevic, Irena et al.
System: The UNT Digital Library
Towards an Error Model for OpenMP (open access)

Towards an Error Model for OpenMP

OpenMP lacks essential features for developing mission-critical software. In particular, it has no support for detecting and handling errors or even a concept of them. In this paper, the OpenMP Error Model Subcommittee reports on solutions under consideration for this major omission. We identify issues with the current OpenMP specification and propose a path to extend OpenMP with error-handling capabilities. We add a construct that cleanly shuts down parallel regions as a first step. We then discuss two orthogonal proposals that extend OpenMP with features to handle system-level and user-defined errors.
Date: March 22, 2010
Creator: Wong, M.; Klemm, M.; Duran, A.; Mattson, T.; Haab, G.; de Supinski, B. R. et al.
System: The UNT Digital Library
A molecularly defined duplication set for the X chromosome of Drosophila melanogaster (open access)

A molecularly defined duplication set for the X chromosome of Drosophila melanogaster

None
Date: July 22, 2010
Creator: Venken, Koen J. T.; Popodi, Ellen; Holtzman, Stacy L.; Schulze, Karen L.; Park, Soo; Carlson, Joseph W. et al.
System: The UNT Digital Library
Enhanced Named Entity Extraction via Error-Driven Aggregation (open access)

Enhanced Named Entity Extraction via Error-Driven Aggregation

Despite recent advances in named entity extraction technologies, state-of-the-art extraction tools achieve insufficient accuracy rates for practical use in many operational settings. However, they are not generally prone to the same types of error, suggesting that substantial improvements may be achieved via appropriate combinations of existing tools, provided their behavior can be accurately characterized and quantified. In this paper, we present an inference methodology for the aggregation of named entity extraction technologies that is founded upon a black-box analysis of their respective error processes. This method has been shown to produce statistically significant improvements in extraction relative to standard performance metrics and to mitigate the weak performance of entity extractors operating under suboptimal conditions. Moreover, this approach provides a framework for quantifying uncertainty and has demonstrated the ability to reconstruct the truth when majority voting fails.
Date: February 22, 2010
Creator: Lemmond, T. D.; Perry, N. C.; Guensche, J. W.; Nitao, J. J.; Glaser, R. E.; Kidwell, P. et al.
System: The UNT Digital Library
SPECTRAL AMPLITUDE AND PHASE EVOLUTION IN PETAWATT LASER PULSES (open access)

SPECTRAL AMPLITUDE AND PHASE EVOLUTION IN PETAWATT LASER PULSES

The influence of the active gain medium on the spectral amplitude and phase of amplified pulses in a CPA system is studied. Results from a 10-PW example based on Nd-doped mixed glasses are presented. In conclusion, this study shows that, by using spectral shaping and gain saturation in a mixed-glass amplifier, it is possible to produce 124 fs, 1.4 kJ laser pulses. One detrimental effect, the pulse distortion due to resonant amplification medium, has been investigated and its magnitude as well as its compensation calculated.
Date: November 22, 2010
Creator: Filip, C V
System: The UNT Digital Library