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Correlation-induced anomalies and extreme sensitivity in fcc-PU1

Description: We have used GGA + U density functional theory to study the effects of correlation on the properties offcc-Pu. We found that the structural and elastic properties offcc-Pu are highly sensitive to the Hubbard U parameter. Within an interval of 0.1 eV ofthe U parameter, the equilibrium lattice constants offcc-Pu can change from 0.44 to 0.47 nm. While the bulk modulus can drop by a factor of5 to 10. The pressure derivative, dB/dp, ofthe bulk modulus can rise dramatically from 5 to 16 and then drop to a negative value before recovering to a more normal value. These observations are partially supported by existing experiments and the prediction of a negative dB/dp needs to be tested in future experiments.
Date: January 1, 2009
Creator: Chen, Shao-ping
Partner: UNT Libraries Government Documents Department

Regression Models for Demand Reduction based on Cluster Analysis of Load Profiles

Description: This paper provides new regression models for demand reduction of Demand Response programs for the purpose of ex ante evaluation of the programs and screening for recruiting customer enrollment into the programs. The proposed regression models employ load sensitivity to outside air temperature and representative load pattern derived from cluster analysis of customer baseline load as explanatory variables. The proposed models examined their performances from the viewpoint of validity of explanatory variables and fitness of regressions, using actual load profile data of Pacific Gas and Electric Company's commercial and industrial customers who participated in the 2008 Critical Peak Pricing program including Manual and Automated Demand Response.
Date: June 28, 2009
Creator: Yamaguchi, Nobuyuki; Han, Junqiao; Ghatikar, Girish; Piette, Mary Ann; Asano, Hiroshi & Kiliccote, Sila
Partner: UNT Libraries Government Documents Department

Sensitivity Assessment of Ozone Models

Description: The activities under this contract effort were aimed at developing sensitivity analysis techniques and fully equivalent operational models (FEOMs) for applications in the DOE Atmospheric Chemistry Program (ACP). MRC developed a new model representation algorithm that uses a hierarchical, correlated function expansion containing a finite number of terms. A full expansion of this type is an exact representation of the original model and each of the expansion functions is explicitly calculated using the original model. After calculating the expansion functions, they are assembled into a fully equivalent operational model (FEOM) that can directly replace the original mode.
Date: January 24, 2000
Creator: Shorter, Jeffrey A.; Rabitz, Herschel A. & Armstrong, Russell A.
Partner: UNT Libraries Government Documents Department

A Rapid Modification of a Standard Disk-plate Antibiotic Susceptibility Test

Description: The objective of the work reported in this paper is one of a two-fold nature. The first objective is to develop a disk-plate sensitivity test that is more rapid than that of existing methods. The second requisite is that the materials, techniques, interpretation, and reporting of results be the sane as those required for the disk-plate method described in the Difco Manual.
Date: January 1955
Creator: Jackson, Leslie Warren
Partner: UNT Libraries

A Generalized {ital K} Correction for Type Ia Supernovae: Comparing {ital R}-band Photometry Beyond {ital z=9.2} with B,V, and {ital R}-band Nearby Photometry

Description: Photometric measurements show that, as a group, nearby Type Ia supernovae follow similar light curves and reach similar peak magnitudes (Branch & Tammann 1992). Thus, these supernovae may serve as standard candles or calibrated candles at cosmological distances. Magnitudes of local and distant supernovae, both in the same filter band, are compared using a K correction to account for the different spectral regions incident on that filter. A generalized approach compares magnitudes in different bands for the nearby and distant supernovae, bands that are selected to give sensitivity in corresponding regions of the unredshifted and redshifted spectra. Thus, R magnitudes for supernovae at z {approx} 0.5 are compared with B magnitudes of local supernovae. We compute these generalized K corrections over a range of redshifts and bandpass pairs and discuss their advantages over the traditional single-band K correction. In particular, errors near maximum light can be kept below 0.05 mag out to at least z = 0.6, whereas the traditional K correction is less accurate and can be difficult to determine beyond z > 0.2.
Date: November 1, 1995
Creator: Kim, Alex; Goodbar, Ariel & Perlmutter, Saul
Partner: UNT Libraries Government Documents Department

Continuous monitoring of crosswell seismic travel time

Description: In two separate shallow field experiments, at two distancescales, we have used continuous monitoring to estimate the effect ofbarometric pressure on crosswell travel time and thereby calibrated thestress sensitivity of the rock volume between the wells. In a 3 mexperiment we found a stress sensitivity of 10-6/Pa while in a 30 mexperiment the sensitivity was 5 x 10-8 /Pa. Results from a deeper (1km), 2 month experiment at the San Andreas fault observation boreholeswill be presented if analysis is completed.
Date: April 14, 2006
Creator: Daley, Thomas M.; Silver, Paul G.; Niu, Fenglin & Majer, Ernest L.
Partner: UNT Libraries Government Documents Department

Butt Joint Tool Status: ITER-US-LLNL-NMARTOVETSKY-01312007

Description: Butt joint tool vacuum vessel has been built at C&H Enterprise, Inc. Leak checking and loading tests were taken place at the factory. The conductor could not be pumped down better than to 500 mtorr and therefore we could not check the sealing mechanism of the seal around conductor. But the rest of the vessel, including the flat gasket, one of the difficult seals worked well, no indication of leak at sensitivity 1e-7 l*torr/sec. The load test showed fully functional system of the load mechanism. The conductors were loaded up to 2200 kgf (21560 N) and the pressure between the butts was uniform with 100% of the contact proved by pressure sensitive film. The status of the butt joint tool development is reported.
Date: February 1, 2007
Creator: Martovetsky, N N
Partner: UNT Libraries Government Documents Department

Sensitivity and Uncertainty Analysis of Occupancy-related Parameters in Energy Modeling of Unt Zero Energy Lab

Description: The study focuses on the sensitivity and uncertainty analysis of occupancy-related parameters using Energyplus modeling method. The model is based on a real building Zero Energy Lab in Discovery Park, at University of North Texas. Four categories of parameters are analyzed: heating/cooling setpoint, lighting, equipment and occupancy. Influence coefficient (IC) is applied in the sensitivity study, in order to compare the impact of individual parameter on the overall building energy consumption. The study is conducted under Texas weather file as well as North Dakota weather file in order to find weather’s influence of sensitivity. Probabilistic collocation method (PCM) is utilized for uncertainty analysis, with an aim of predicting future energy consumption based on history or reference data set. From the study, it is found that cooling setpoint has the largest influence on overall energy consumption in both Texas and North Dakota, and occupancy number has the least influence. The analysis also indicates schedule’s influence on energy consumption. PCM is able to accurately predict future energy consumption with limited calculation, and has great advantage over Monte Carlo Method. The polynomial equations are generated in both 3-order and 6-order, and the 6-order equation is proved to have a better result, which is around 0.1% compared with real value.
Date: August 2013
Creator: Xiong, Guangyuan
Partner: UNT Libraries

Critical dimension sensitivity to post-exposure bake temperaturevariation in EUV photoresists

Description: Chemically amplified resists depend upon the post-exposure bake (PEB) process to drive the deprotection reactions (in positive resists) that lead to proper resist development. For this reason they often exhibit critical dimension (CD) sensitivity to PEB temperature variation. In this work the effects of variation in different aspects of the PEB step on post-develop CD are studied for two extreme ultraviolet (EUV) photoresists. The spatial and temporal temperature uniformity of the PEB plate is measured using a wireless sensor wafer. Programmed variations in the bake plate temperature set point are then used to measure the CD sensitivity to steady state temperature variation. In addition, the initial temperature ramp time is modified using a thin sheet of polyimide film between the wafer and the bake plate. This allows for measurement of the CD sensitivity to transient temperature variation. Finally, the bake time is adjusted to measure the CD sensitivity to this parameter.
Date: January 11, 2005
Creator: Cain, Jason P.; Naulleau, Patrick & Spanos, Costas J.
Partner: UNT Libraries Government Documents Department

iTOUGH2 Command Reference

Description: iTOUGH2 is a program for parameter estimation, sensitivity analysis, and uncertainty propagation analysis. It is based on the TOUGH2 simulator for non-isothermal multiphase flow in fractured and porous media. This report contains a detailed description of all iTOUGH2 commands.
Date: June 18, 2002
Creator: Finsterle, Stefan
Partner: UNT Libraries Government Documents Department

iTOUGH2 Sample Problems

Description: iTOUGH2 is a program for parameter estimation, sensitivity analysis, and uncertainty propagation analysis. It is based on the TOUGH2 simulator for non-isothermal multiphase flow in fractured and porous media. This report contains a collection of iTOUGH2 sample problems.
Date: June 18, 2002
Creator: Finsterle, Stefan
Partner: UNT Libraries Government Documents Department

Evaluation of flow capture techniques for measuring HVAC grilleairflows

Description: This paper discusses the accuracy of commercially available flow hoods for residential applications. Results of laboratory and field tests indicate these hoods can be inadequate to measure airflows in residential systems, and there can be large measurement discrepancies between different flow hoods. The errors are due to poor calibrations, sensitivity of the hoods to grille airflow non-uniformities, and flow changes from added flow resistance. It is possible to obtain reasonable results using some flow hoods if the field tests are carefully done, the grilles are appropriate, and grille location does not restrict flow hood placement. We also evaluated several simple flow capture techniques for measuring grille airflows that could be adopted by the HVAC industry and homeowners as simple diagnostics. These simple techniques can be as accurate as commercially available devices. Our test results also show that current calibration procedures for flow hoods do not account for field application problems. As a result, agencies such as ASHRAE or ASTM need to develop a new standard for flow hood calibration, along with a new measurement standard to address field use of flow capture techniques.
Date: November 1, 2002
Creator: Walker, Iain S. & Wray, Craig P.
Partner: UNT Libraries Government Documents Department

Interspecific Differences in Metabolic Rate and Metabolic Temperature Sensitivity Create Distinct Thermal Ecological Niches in Lizards (Plestiodon)

Description: This article examines three congeneric lizards from the southeastern United States (Plestiodon fasciatus, P. inexpectatus, and P. laticeps) and hypothesizes that interspecific differences in metabolic temperature sensitivity locally segregates them across their total range.
Date: October 19, 2016
Creator: Watson, Charles M. & Burggren, Warren W.
Partner: UNT College of Arts and Sciences

Sensitivity Enhancement by Exchange Mediated MagnetizationTransfer of the Xenon Biosensor Signal

Description: Hyperpolarized xenon associated with ligand derivitized cryptophane-A cages has been developed as a NMR based biosensor. To optimize the detection sensitivity we describe use of xenon exchange between the caged and bulk dissolved xenon as an effective signal amplifier. This approach, somewhat analogous to 'remote detection' described recently, uses the chemical exchange to repeatedly transfer spectroscopic information from caged to bulk xenon, effectively integrating the caged signal. After an optimized integration period, the signal is read out by observation of the bulk magnetization. The spectrum of the caged xenon is reconstructed through use of a variable evolution period before transfer and Fourier analysis of the bulk signal as a function of the evolution time.
Date: August 31, 2006
Creator: Garcia, Sandra; Chavez, Lana; Lowery, Thomas J.; Han, Song-I.; Wemmer, David E. & Pines, Alexander
Partner: UNT Libraries Government Documents Department

TPV Network Sensitivity: A Simulation Study

Description: A viable thermophotovoltaic power conversion system requires an electrically connected network of diodes that is designed to be fault tolerant for a prescribed power rating and generator life. This paper describes simulation studies investigating the sensitivity of various series/parallel network configurations to diode variability. The results show the effect of diode mismatch and reverse breakdown behavior on network performance.
Date: February 10, 2004
Creator: Vell, J.L.; Oppenlander, J.E.; Gaes, W.S.; Siganporia, D.M. & Danielson, L.R.
Partner: UNT Libraries Government Documents Department

Evaluation of In Situ Combustion for Schrader Bluff

Description: The focus of this report is on the results related to evaluation of in situ combustion processes applied to Schrader Bluff. Initially, overall screening processes were applied to determine which of the EOR methods, were most appropriate for Schrader Bluff. In situ combustion was among the methods considered potentially favorable and was evaluated further. Laboratory scale tube runs were conducted to determine if the kinetic parameters for the crude oil were favorable. Additional sensitivity studies were conducted to evaluate the recovery potential. Described in this report are the results of the (1) initial screening,(2) experimental tube runs, and (3) simulation sensitivity studies as related to in situ combustion in Schrader Bluff.
Date: March 11, 1999
Creator: Sarathi, P.; Strycker, A. & Wang, S.
Partner: UNT Libraries Government Documents Department

Shock Initiation of New and Aged PBX 9501 Measured with Embedded Electromagnetic Particle Velocity Gauges

Description: We have used an embedded electromagnetic particle velocity gauge technique to measure the shock initiation behavior in PBX 9501 explosive. Up to twelve separate particle velocity wave profile measurements have been made at different depths in a single experiment. These detail the growth from an input shock to a detonation. In addition, another gauge element called a ''shock tracker'' has been used to monitor the progress of the shock front as a function of time and position as it moves through the explosive sample. This provides data similar to that obtained in a traditional explosively driven wedge test and is used to determine the position and time that the wave attains detonation. Run distance-to-detonation vs. input pressure (Pop-plot) data and particle velocity wave profile data have been obtained on new PBX 9501 pressed to densities of 1.826, 1.830, and 1.837 g/cm{sup 3}. In addition, the same measurements were performed on aged material recovered from dismantled W76 and W78 weapons. The input pressure range covered was 3.0 to 5.2 GPa. All results to date show shock sensitivity to be a function only of the initial density and not of age. PBX 9501 shock initiates the same after 17 years in stockpile as it does on the day it is pressed. Particle velocity wave profiles show mixed heterogeneous initiation (growth in the front) and homogeneous initiation (growth behind the front).
Date: September 1, 1999
Creator: Hill, L. G.; Gustavsen, R. L.; Alcon, R. R. & Sheffield, S. A.
Partner: UNT Libraries Government Documents Department

Feasibility of Using Remote-Sensing Techniques for Shoreline Delineation and Coastal Habitat Classification for Environmental Sensitivity Index (ESI) Mapping

Description: Environmental Sensitivity Index (ESI) provides shoreline classification and a sensitivity ranking that is important for oil spill planning. This system has not been used in Louisiana due to the rapid changes of the shoreline, which is a potential threat due to high risk of oil spill in that region. This research paper's goal is to develop remote sensing classification procedures to create an ESI map for Louisiana and other areas that present similar issues.
Date: August 2005
Creator: Born-Phillips, Katherine; Locke, Chris; Michel, Jacqueline & Braud, DeWitt
Partner: UNT Libraries Government Documents Department

An Evaluation of Music Appreciation Courses in Selected Institutions of Higher Learning by Measuring Change in the Sensitivity of the Students to Form and Style in Unfamiliar Music

Description: The present study is an evaluation of music appreciation courses in selected institutions of higher learning by measuring change in the sensitivity of the students to form and style in unfamiliar music.
Date: August 1969
Creator: Smith, George Francis, 1931-
Partner: UNT Libraries

The Construction of a Dependable Instrument of Measurement in the Field of Social Sensitivity

Description: The problem of this study is an attempt to construct a dependable instrument of measurement in the field of social sensitivity. An endeavor will be made to make this instrument sensitive enough to give some degree of precision and reliability to its results. Other attempted methods of measurement applied to this quantity have given results only in scattered generalities.
Date: 1941
Creator: Middleton, Charles E.
Partner: UNT Libraries

Sensitivity study of reliable, high-throughput resolution metricsfor photoresists

Description: The resolution of chemically amplified resists is becoming an increasing concern, especially for lithography in the extreme ultraviolet (EUV) regime. Large-scale screening and performance-based down-selection is currently underway to identify resist platforms that can support shrinking feature sizes. Resist screening efforts, however, are hampered by the absence of reliable resolution metrics that can objectively quantify resist resolution in a high-throughput fashion. Here we examine two high-throughput metrics for resist resolution determination. After summarizing their details and justifying their utility, we characterize the sensitivity of both metrics to two of the main experimental uncertainties associated with lithographic exposure tools, namely: limited focus control and limited knowledge of optical aberrations. For an implementation at EUV wavelengths, we report aberration and focus limited error bars in extracted resolution of {approx} 1.25 nm RMS for both metrics making them attractive candidates for future screening and down-selection efforts.
Date: July 30, 2007
Creator: Anderson, Christopher N. & Naulleau, Patrick P.
Partner: UNT Libraries Government Documents Department