Advanced technologies for remote sensing imaging applications (open access)

Advanced technologies for remote sensing imaging applications

Generating and returning imagery from great distances has been generally associated with national security activities, with emphasis on reliability of system operation. (While the introduction of such capabilities was usually characterized by high levels of innovation, the evolution of such systems has followed the classical track of proliferation of ``standardized items`` expressing ever more incremental technological advances.) Recent focusing of interest on the use of remote imaging systems for commercial and scientific purposes can be expected to induce comparatively rapid advances along the axes of efficiency and technological sophistication, respectively. This paper reviews the most basic reasons for expecting the next decade of advances to dwarf the impressive accomplishments of the past ten years. The impact of these advances clearly will be felt in all major areas of large-scale human endeavor, commercial, military and scientific.
Date: June 7, 1993
Creator: Wood, L. L.
System: The UNT Digital Library
Advances in Modeling Radiation Dispersal Device and Nuclear Detonation Effects (open access)

Advances in Modeling Radiation Dispersal Device and Nuclear Detonation Effects

None
Date: June 7, 2011
Creator: Nasstrom, J. S.; Foster, K. T.; Goldstein, P.; Dillon, M. B.; Wimer, N. G.; Homann, S. et al.
System: The UNT Digital Library
Analysis of an Information Monitoring and Diagnostic System to Improve Building Operations (open access)

Analysis of an Information Monitoring and Diagnostic System to Improve Building Operations

None
Date: June 7, 2000
Creator: Piette, Mary Ann; Kinney, Satkartar & Haves, Philip
System: The UNT Digital Library
Analysis of Potential Energy Saving and CO2 Emission Reduction of Home Appliances and Commercial Equipments in China (open access)

Analysis of Potential Energy Saving and CO2 Emission Reduction of Home Appliances and Commercial Equipments in China

China is now the world's largest producer and consumer of household appliances and commercial equipment. To address the growth of electricity use of the appliances, China has implemented a series of minimum energy performance standards (MEPS) for 30 appliances, and voluntary energy efficiency label for 40 products. Further, in 2005, China started a mandatory energy information label that covers 19 products to date. However, the impact of these standard and labeling programs and their savings potential has not been evaluated on a consistent basis. This research involved modeling to estimate the energy saving and CO{sub 2} emission reduction potential of the appliances standard and labeling program for products for which standards are currently in place, or under development and those proposed for development in 2010. Two scenarios that have been developed differ primarily in the pace and stringency of MEPS development. The 'Continued Improvement Scenario' (CIS) reflects the likely pace of post-2009 MEPS revisions, and the likely improvement at each revision step considering the technical limitation of the technology. The 'Best Practice Scenario' (BPS) examined the potential of an achievement of international best practice MEPS in 2014. This paper concludes that under the 'CIS' of regularly scheduled MEPS revisions to …
Date: June 7, 2010
Creator: Zhou, Nan; Fridley, David; McNeill, Michael; Zheng, Nina; Letschert, Virginie; Ke, Jing et al.
System: The UNT Digital Library
Application of mid-infrared spectroscopy to the identification of materials and to the determination of surface coatings (open access)

Application of mid-infrared spectroscopy to the identification of materials and to the determination of surface coatings

A small user friendly, light-weight, field hardened, computer controlled device for performing infrared spectroscopic analysis, with high sensitivity of trace contamination on surfaces, has recently been defined by Lockheed Martin Energy Systems, Inc. The National Aeronautics and Space Administration at Marshall Space Flight Center, Alabama (NASA/MSFC) initiated a development contract to field a production model of this device with Surface Optics Corporation, San Diego, California in order to certify the sandblasted inner surface of solid rocket motor casings to be free of both hydrocarbon grease and silicone oils at levels approaching 1 milligram per square foot. Through contracts with Lockheed Martin Energy Systems, Inc., the Army acquired a prototype of this instrument, which was used for optimizing the performance with respect to detecting trace organic contamination on sandblasted metal surfaces. That prototype has since been upgraded to incorporate the refinements discovered in its use, and is presently being field tested by the Army at the Corpus Christi Army Depot (CCAD). Referred to as a surface inspection machine-infrared (SIMIR or SOC 400), this device employs a miniature Fourier transform Infrared spectrometer (FTIRS) with very efficient diffuse reflectance optics to provide reflectance spectra of surfaces measured relative to some reference surface. These …
Date: June 7, 1996
Creator: Powell, G. L.; Engbert, E. G.; Holiday, J. & Velez, J. L.
System: The UNT Digital Library
APPLICATIONS OF IR THERMOGRAPHY IN CAPTURING THERMAL TRANSIENTS AND OTHER HIGH SPEED THERMAL EVENT (open access)

APPLICATIONS OF IR THERMOGRAPHY IN CAPTURING THERMAL TRANSIENTS AND OTHER HIGH SPEED THERMAL EVENT

The high-speed, snap-shot mode, and the external triggering capability of an IR camera allows thermal transients to be captured. These advanced features were used to capture thermal transients during electrical breakdown of ZnO varistors and to freeze the rotation of an automobile disk brake in order to study thermoplastic instability in the braking system. The IR camera also showed the thermoplastic effect during cyclic fatigue testing of a glass matrix composite.
Date: June 7, 1999
Creator: Wang, H.; Dinwiddie, R. B. & Graham, S.
System: The UNT Digital Library
Approximate Identification of Boundary Properties in a Wave Equation by Optimal Control Techniques (open access)

Approximate Identification of Boundary Properties in a Wave Equation by Optimal Control Techniques

We apply optimal control techniques to find approximate solutions to an inverse problem for the acoustic wave equation. The inverse problem is to determine the shape and reflection coefficient of a part of the boundary from partial measurements of the acoustic signal. The sought functions are treated as controls and the goal is to drive the model solution close to the experimental data by adjusting these functions.
Date: June 7, 1999
Creator: Lenhart, S.; Protopopescu, V. & Yong, J.
System: The UNT Digital Library
Assessment of Building Energy-Saving Policies and Programs in China During the 11th Five Year Plan (open access)

Assessment of Building Energy-Saving Policies and Programs in China During the 11th Five Year Plan

China's 11th Five-Year Plan (FYP) sets an ambitious target to reduce the energy intensity per unit of gross domestic product (GDP) by 20% from 2005 to 2010 (NDRC, 2006). In the building sector, the primary energy-saving target allocated during the 11 FYP period is 100 Mtce. Savings are expected to be achieved through the strengthening of enforcement of building energy efficiency codes, existing building retrofits and heat supply system reform, followed by energy management of government office buildings and large scale public buildings, adoption of renewable energy sources. To date, China has reported that it achieved the half of the 20% intensity reduction target by the end of 2008, however, little has been made clear on the status and the impact of the building programs. There has also been lack of description on methodology for calculating the savings and baseline definition, and no total savings that have been officially reported to date. This paper intend to provide both quantitative and qualitative assessment of the key policies and programs in building sector that China has instituted in its quest to fulfill the national goal. Overall, this paper concludes that the largest improvement for building energy efficiency were achieved in new buildings; …
Date: June 7, 2010
Creator: Zhou, Nan; McNeil, Michael & Levine, Mark
System: The UNT Digital Library
Atlas Pulsed Power Facility for High Energy Density Physics Experiments (open access)

Atlas Pulsed Power Facility for High Energy Density Physics Experiments

The Atlas facility, now under construction at Los Alamos National Laboratory (LANL), will provide a unique capability for performing high-energy-density experiments in support of weapon-physics and basic-research programs. It is intended to be an international user facility, providing opportunities for researchers from national laboratories and academic institutions around the world. Emphasizing institutions around the world. Emphasizing hydrodynamic experiments, Atlas will provide the capability for achieving steady shock pressures exceeding 10-Mbar in a volume of several cubic centimeters. In addition, the kinetic energy associated with solid liner implosion velocities exceeding 12 km/s is sufficient to drive dense, hydrodynamic targets into the ionized regime, permitting the study of complex issues associated with strongly-coupled plasmas. The primary element of Atlas is a 23-MJ capacitor bank, comprised of 96 separate Marx generators housed in 12 separate oil-filled tanks, surrounding a central target chamber. Each tank will house two, independently-removable maintenance units, with each maintenance unit consisting of four Marx modules. Each Marx module has four capacitors that can each be charged to a maximum of 60 kilovolts. When railgap switches are triggered, the marx modules erect to a maximum of 240 kV. The parallel discharge of these 96 Marx modules will deliver a 30-MA …
Date: June 7, 1999
Creator: Miller, R. B.; Ballard, E. O.; Barr, G. W.; Bowman, D. W.; Chochrane, J. C.; Davis, H. A. et al.
System: The UNT Digital Library
Baryonic B Decays (open access)

Baryonic B Decays

None
Date: June 7, 2013
Creator: Shiu, Jing-Ge & /Taiwan, Natl. Taiwan U.
System: The UNT Digital Library
The BigBoss Experiment (open access)

The BigBoss Experiment

BigBOSS is a Stage IV ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with a wide-area galaxy and quasar redshift survey over 14,000 square degrees. It has been conditionally accepted by NOAO in response to a call for major new instrumentation and a high-impact science program for the 4-m Mayall telescope at Kitt Peak. The BigBOSS instrument is a robotically-actuated, fiber-fed spectrograph capable of taking 5000 simultaneous spectra over a wavelength range from 340 nm to 1060 nm, with a resolution R = {lambda}/{Delta}{lambda} = 3000-4800. Using data from imaging surveys that are already underway, spectroscopic targets are selected that trace the underlying dark matter distribution. In particular, targets include luminous red galaxies (LRGs) up to z = 1.0, extending the BOSS LRG survey in both redshift and survey area. To probe the universe out to even higher redshift, BigBOSS will target bright [OII] emission line galaxies (ELGs) up to z = 1.7. In total, 20 million galaxy redshifts are obtained to measure the BAO feature, trace the matter power spectrum at smaller scales, and detect redshift space distortions. BigBOSS will provide additional constraints on early dark energy and on the curvature of …
Date: June 7, 2012
Creator: Schelgel, D.; Abdalla, F.; Abraham, T.; Ahn, C.; Allende Prieto, C.; Annis, J. et al.
System: The UNT Digital Library
Bioremediation of Petroleum and Radiological Contaminated Soils at the Savannah River Site: Laboratory to Field Scale Applications (open access)

Bioremediation of Petroleum and Radiological Contaminated Soils at the Savannah River Site: Laboratory to Field Scale Applications

In the process of Savannah River Site (SRS) operations limited amounts of waste are generated containing petroleum, and radiological contaminated soils. Currently, this combination of radiological and petroleum contaminated waste does not have an immediate disposal route and is being stored in low activity vaults. SRS developed and implemented a successful plan for clean up of the petroleum portion of the soils in situ using simple, inexpensive, bioreactor technology. Treatment in a bioreactor removes the petroleum contamination from the soil without spreading radiological contamination to the environment. This bioreactor uses the bioventing process and bioaugmentation or the addition of the select hydrocarbon degrading bacteria. Oxygen is usually the initial rate-limiting factor in the biodegradation of petroleum hydrocarbons. Using the bioventing process allowed control of the supply of nutrients and moisture based on petroleum contamination concentrations and soil type. The results of this work have proven to be a safe and cost-effective means of cleaning up low level radiological and petroleum-contaminated soil. Many of the other elements of the bioreactor design were developed or enhanced during the demonstration of a ''biopile'' to treat the soils beneath a Polish oil refinery's waste disposal lagoons. Aerobic microorganisms were isolated from the aged refinery's …
Date: June 7, 2004
Creator: BRIGMON, ROBINL.
System: The UNT Digital Library
Broad Line Radio Galaxies Observed with Fermi-LAT: The Origin of the GeV Gamma-Ray Emission (open access)

Broad Line Radio Galaxies Observed with Fermi-LAT: The Origin of the GeV Gamma-Ray Emission

We report on a detailed investigation of the {gamma}-ray emission from 18 broad line radio galaxies (BLRGs) based on two years of Fermi Large Area Telescope (LAT) data. We confirm the previously reported detections of 3C 120 and 3C 111 in the GeV photon energy range; a detailed look at the temporal characteristics of the observed {gamma}-ray emission reveals in addition possible flux variability in both sources. No statistically significant {gamma}-ray detection of the other BLRGs was however found in the considered dataset. Though the sample size studied is small, what appears to differentiate 3C 111 and 3C 120 from the BLRGs not yet detected in {gamma}-rays is the particularly strong nuclear radio flux. This finding, together with the indications of the {gamma}-ray flux variability and a number of other arguments presented, indicate that the GeV emission of BLRGs is most likely dominated by the beamed radiation of relativistic jets observed at intermediate viewing angles. In this paper we also analyzed a comparison sample of high accretion-rate Seyfert 1 galaxies, which can be considered radio-quiet counterparts of BLRGs, and found none were detected in {gamma}-rays. A simple phenomenological hybrid model applied for the broad-band emission of the discussed radio-loud and …
Date: June 7, 2012
Creator: Kataoka, J.; Stawarz, L.; Takahashi, Y.; Cheung, C. C.; Hayashida, M.; Grandi, P. et al.
System: The UNT Digital Library
Calculations for Tera-Hertz (THZ) Radiation Sources (open access)

Calculations for Tera-Hertz (THZ) Radiation Sources

We explore possibilities for THz sources from 0.3-30 THz. While still inaccessible, this broad gap is even wider for advanced acceleration schemes extending from X or, at most, W band RF at the low end up to CO{sub 2} lasers. While the physical implementations of these two approaches are quite different, both are proving difficult to develop so that lower frequency, superconducting RF is currently preferred. Similarly, the validity of modeling techniques varies greatly over this range of frequencies but generally mandates coupling Maxwell's equations to the appropriate device transport physics for which there are many options. Here we study radiation from undulatory-shaped transmission lines using finite-difference, time-domain (FDTD) simulations. Also, we present Monte-Carlo techniques for pulse generation. Examples of THz sources demonstrating coherence are shown with the goal of optimizing on-chip THz radiators for applications that may lead to accelerators.
Date: June 7, 2005
Creator: Hussein, Yasser A. & Spencer, James E.
System: The UNT Digital Library
Causes of Color in Minerals and Gemstones (open access)

Causes of Color in Minerals and Gemstones

None
Date: June 7, 2000
Creator: HLAVA,PAUL F.
System: The UNT Digital Library
Characterization and Reconstruction of Nanolipoprotein Particles (Nlps) by Cryo-EM and Image Reconstruction (open access)

Characterization and Reconstruction of Nanolipoprotein Particles (Nlps) by Cryo-EM and Image Reconstruction

Nanolipoprotein particles (NLPs) are small 10-20 nm diameter assemblies of apolipoproteins and lipids. At Lawrence Livermore National Laboratory (LLNL), they have constructed multiple variants of these assemblies. NLPs have been generated from a variety of lipoproteins, including apolipoprotein Al, apolipophorin III, apolipoprotein E4 22K, and MSP1T2 (nanodisc, Inc.). Lipids used included DMPC (bulk of the bilayer material), DMPE (in various amounts), and DPPC. NLPs were made in either the absence or presence of the detergent cholate. They have collected electron microscopy data as a part of the characterization component of this research. Although purified by size exclusion chromatography (SEC), samples are somewhat heterogeneous when analyzed at the nanoscale by negative stained cryo-EM. Images reveal a broad range of shape heterogeneity, suggesting variability in conformational flexibility, in fact, modeling studies point to dynamics of inter-helical loop regions within apolipoproteins as being a possible source for observed variation in NLP size. Initial attempts at three-dimensional reconstructions have proven to be challenging due to this size and shape disparity. They are pursuing a strategy of computational size exclusion to group particles into subpopulations based on average particle diameter. They show here results from their ongoing efforts at statistically and computationally subdividing NLP populations …
Date: June 7, 2007
Creator: Pesavento, Joseph B.; Morgan, David; Bermingham, Rachelle; Zamora, Deborah; Chromy, Brett; Segelke, Brent et al.
System: The UNT Digital Library
Classification of non-coding RNA using graph representations ofsecondary structure (open access)

Classification of non-coding RNA using graph representations ofsecondary structure

Some genes produce transcripts that function directly in regulatory, catalytic, or structural roles in the cell. These non-coding RNAs are prevalent in all living organisms, and methods that aid the understanding of their functional roles are essential. RNA secondary structure, the pattern of base-pairing, contains the critical information for determining the three dimensional structure and function of the molecule. In this work we examine whether the basic geometric and topological properties of secondary structure are sufficient to distinguish between RNA families in a learning framework. First, we develop a labeled dual graph representation of RNA secondary structure by adding biologically meaningful labels to the dual graphs proposed by Gan et al [1]. Next, we define a similarity measure directly on the labeled dual graphs using the recently developed marginalized kernels [2]. Using this similarity measure, we were able to train Support Vector Machine classifiers to distinguish RNAs of known families from random RNAs with similar statistics. For 22 of the 25 families tested, the classifier achieved better than 70% accuracy, with much higher accuracy rates for some families. Training a set of classifiers to automatically assign family labels to RNAs using a one vs. all multi-class scheme also yielded encouraging …
Date: June 7, 2004
Creator: Karklin, Yan; Meraz, Richard F. & Holbrook, Stephen R.
System: The UNT Digital Library
Closing in on a Short-Hard Burst Progenitor: Constraints From Early-Time Optical Imaging and Spectroscopy of a Possible Host Galaxy of GRB 050509b (open access)

Closing in on a Short-Hard Burst Progenitor: Constraints From Early-Time Optical Imaging and Spectroscopy of a Possible Host Galaxy of GRB 050509b

The localization of the short-duration, hard-spectrum gamma-ray burst GRB050509b by the Swift satellite was a watershed event. Never before had a member of this mysterious subclass of classic GRBs been rapidly and precisely positioned in a sky accessible to the bevy of ground-based follow-up facilities. Thanks to the nearly immediate relay of the GRB position by Swift, we began imaging the GRB field 8 minutes after the burst and have continued during the 8 days since. Though the Swift X-ray Telescope (XRT) discovered an X-ray afterglow of GRB050509b, the first ever of a short-hard burst, thus far no convincing optical/infrared candidate afterglow or supernova has been found for the object. We present a re-analysis of the XRT afterglow and find an absolute position of R.A. = 12h36m13.59s, Decl. = +28{sup o}59'04.9'' (J2000), with a 1{sigma} uncertainty of 3.68'' in R.A., 3.52'' in Decl.; this is about 4'' to the west of the XRT position reported previously. Close to this position is a bright elliptical galaxy with redshift z = 0.2248 {+-} 0.0002, about 1' from the center of a rich cluster of galaxies. This cluster has detectable diffuse emission, with a temperature of kT = 5.25{sub -1.68}{sup +3.36} keV. We …
Date: June 7, 2005
Creator: Bloom, Joshua S.; Prochaska, J. X.; Pooley, D.; Blake, C. W.; Foley, R. J.; Jha, S. et al.
System: The UNT Digital Library
Collective behavior in recent laser-plasma experiments (open access)

Collective behavior in recent laser-plasma experiments

The absorption of 1.06 ..mu.. light focused on small C/sub 8/H/sub 8/ discs has been measured in the intensity range of 10/sup 15/ - 10/sup 17/ W/cm. The data confirms the importance of collective plasma effects in determining the absorption of intense light. The measured absorption efficiencies are in the range of 30 to 40 percent, and the scattered light has a polarization dependence. The measured absorptions are shown to be inconsistent with classical inverse bremsstrahlung. Both the magnitude of the absorption and the observed polarization dependence of the scattered light are shown to be consistent with recent calculations of light absorption via collective processes. Comparisons are made, and improved models of the light absorption are discussed with reference to the data. In addition, the heated electron energies deduced from the x-ray data are consistent with those expected via collective processes.
Date: June 7, 1976
Creator: Kruer, W. L.; Haas, R. A.; Mead, W. C.; Phillion, D. W. & Rupert, V. C.
System: The UNT Digital Library
Compact, Intelligent, Digitally Controlled IGBT Gate Drivers for a PEBB-Based ILC Marx Modulator (open access)

Compact, Intelligent, Digitally Controlled IGBT Gate Drivers for a PEBB-Based ILC Marx Modulator

SLAC National Accelerator Laboratory has built and is currently operating a first generation prototype Marx klystron modulator to meet ILC specifications. Under development is a second generation prototype, aimed at improving overall performance, serviceability, and manufacturability as compared to its predecessor. It is designed around 32 cells, each operating at 3.75 kV and correcting for its own capacitor droop. Due to the uniqueness of this application, high voltage gate drivers needed to be developed for the main 6.5 kV and droop correction 1.7 kV IGBTs. The gate driver provides vital functions such as protection of the IGBT from over-voltage and over-current, detection of gate-emitter open and short circuit conditions, and monitoring of IGBT degradation (based on collector-emitter saturation voltage). Gate drive control, diagnostic processing capabilities, and communication are digitally implemented using an FPGA. This paper details the design of the gate driver circuitry, component selection, and construction layout. In addition, experimental results are included to illustrate the effectiveness of the protection circuit.
Date: June 7, 2010
Creator: Nguyen, M. N.; Burkhart, C.; Olsen, J. J. & Macken, K.
System: The UNT Digital Library
Compact Linear Accelerator Sources for Gamma-ray Generation (open access)

Compact Linear Accelerator Sources for Gamma-ray Generation

None
Date: June 7, 2011
Creator: Anderson, S. G.; Barty, C. P.; Beer, G.; Cross, R. R.; Ebbers, C. A.; Gibson, D. J. et al.
System: The UNT Digital Library
Comparison of chiller models for use in model-based fault detection (open access)

Comparison of chiller models for use in model-based fault detection

Selecting the model is an important and essential step in model based fault detection and diagnosis (FDD). Factors that are considered in evaluating a model include accuracy, training data requirements, calibration effort, generality, and computational requirements. The objective of this study was to evaluate different modeling approaches for their applicability to model based FDD of vapor compression chillers. Three different models were studied: the Gordon and Ng Universal Chiller model (2nd generation) and a modified version of the ASHRAE Primary Toolkit model, which are both based on first principles, and the DOE-2 chiller model, as implemented in CoolTools{trademark}, which is empirical. The models were compared in terms of their ability to reproduce the observed performance of an older, centrifugal chiller operating in a commercial office building and a newer centrifugal chiller in a laboratory. All three models displayed similar levels of accuracy. Of the first principles models, the Gordon-Ng model has the advantage of being linear in the parameters, which allows more robust parameter estimation methods to be used and facilitates estimation of the uncertainty in the parameter values. The ASHRAE Toolkit Model may have advantages when refrigerant temperature measurements are also available. The DOE-2 model can be expected to …
Date: June 7, 2001
Creator: Sreedharan, Priya & Haves, Philip
System: The UNT Digital Library
Controller/evaluator practicum - enhancing classroom training with field practice. (open access)

Controller/evaluator practicum - enhancing classroom training with field practice.

None
Date: June 7, 2002
Creator: Lacher, L. & Newsom, D.
System: The UNT Digital Library
Cooperative sentry vehicles and differential GPS leapfrog (open access)

Cooperative sentry vehicles and differential GPS leapfrog

As part of a project for the Defense Advanced Research Projects Agency, Sandia National Laboratories Intelligent Systems and Robotics Center is developing and testing the feasibility of using a cooperative team of robotic sentry vehicles to guard a perimeter, perform a surround task, and travel extended distances. This paper describes the authors most recent activities. In particular, this paper highlights the development of a Differential Global Positioning System (DGPS) leapfrog capability that allows two or more vehicles to alternate sending DGPS corrections. Using this leapfrog technique, this paper shows that a group of autonomous vehicles can travel 22.68 kilometers with a root mean square positioning error of only 5 meters.
Date: June 7, 2000
Creator: Feddema, John T.; Lewis, Christopher L. & LaFarge, Robert A.
System: The UNT Digital Library