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Comparison of STIS and SNAP spectrograph throughputs

Description: This is a comparison of the measured throughput of STIS on HST versus what we might expect from the spectrograph on SNAP. The principle reference is Woodgate et al. (1998) PASP, 110, 1183. Additional material was taken from the STIS Handbook, available on-line at www.stsci.edu. The goal is to demonstrate that there are sound reasons to expect better performance for a SNAP spectrograph (even one with a grating) than would be expected by scaling from HST+STIS.
Date: June 30, 2002
Creator: Aldering, Greg
Partner: UNT Libraries Government Documents Department

Analysis of Illumina Microbial Assemblies

Description: Since the emerging of second generation sequencing technologies, the evaluation of different sequencing approaches and their assembly strategies for different types of genomes has become an important undertaken. Next generation sequencing technologies dramatically increase sequence throughput while decreasing cost, making them an attractive tool for whole genome shotgun sequencing. To compare different approaches for de-novo whole genome assembly, appropriate tools and a solid understanding of both quantity and quality of the underlying sequence data are crucial. Here, we performed an in-depth analysis of short-read Illumina sequence assembly strategies for bacterial and archaeal genomes. Different types of Illumina libraries as well as different trim parameters and assemblers were evaluated. Results of the comparative analysis and sequencing platforms will be presented. The goal of this analysis is to develop a cost-effective approach for the increased throughput of the generation of high quality microbial genomes.
Date: May 28, 2010
Creator: Clum, Alicia; Foster, Brian; Froula, Jeff; LaButti, Kurt; Sczyrba, Alex; Lapidus, Alla et al.
Partner: UNT Libraries Government Documents Department

Measurements of slant and vertical TEC using data from FORTE and the TRACKER ray-tracing code

Description: In a previous informal report, the author described the FORTE satellite and the analysis techniques used to extract a slant TEC from measurements of the dispersion of a signal transmitted from and EMP generator at Los Alamos. In this report he reports on the use of a ray-tracing/ionospheric model code to deduce the vertical TEC to 800 km from the FORTE measurements.
Date: December 12, 1997
Creator: Massey, R.S.
Partner: UNT Libraries Government Documents Department

Empirical model for shell-corrected level densities

Description: An empirical model for calculating level densities of closed and near- closed shell nuclei has been developed and tested. This method is based on the calculation of shell plus pairing corrections for each relevant nuclide. A new version of the ALICE code is used to extract these corrections from the Myers-Swiatecki mass formula and to apply them to the calculation of effective excitations in level densities. The corrections are applied in a backshifted fashion to assure correct threshold dependence. We compare our calculated results with experimental data for the production of 56Ni and 88Y to test shell corrections near f7/c closure and the N=50 neutron shell. We also compare our results with those using pure Fermi gas (plus pairing) level densities, and with the more computationally intensive model of Kataria and Ramamurthy.
Date: April 29, 1997
Creator: Ross, M.A. & Blann, M.
Partner: UNT Libraries Government Documents Department

Summary of DOE Incineration Capabilities

Description: This document summarizes and compares operating capacities, waste acceptance criteria, and permits pertaining to the U.S. Department of Energy's three mixed waste incinerators. The information will assist Department evaluation of the incinerators.
Date: July 1998
Creator: Knecht, M.
Partner: UNT Libraries Government Documents Department

A First Look at Modern Enterprise Traffic

Description: While wide-area Internet traffic has been heavily studied for many years, the characteristics of traffic inside Internet enterprises remain almost wholly unexplored. Nearly all of the studies of enterprise traffic available in the literature are well over a decade old and focus on individual LANs rather than whole sites. In this paper we present a broad overview of internal enterprise traffic recorded at a medium-sized site. The packet traces span more than 100 hours, over which activity from a total of several thousand internal hosts appears. This wealth of data--which we are publicly releasing in anonymized form--spans a wide range of dimensions. While we cannot form general conclusions using data from a single site, and clearly this sort of data merits additional in-depth study in a number of ways, in this work we endeavor to characterize a number of the most salient aspects of the traffic. Our goal is to provide a first sense of ways in which modern enterprise traffic is similar to wide-area Internet traffic, and ways in which it is quite different.
Date: June 1, 2005
Creator: Pang, Ruoming; Mark Allman, Mark; Bennett, Mike; Lee, Jason; Paxson, Vern & Tierney, Brian
Partner: UNT Libraries Government Documents Department

Comparative economics for DUCRETE spent fuel storage cask handling, transportation, and capital requirements

Description: This report summarizes economic differences between a DUCRETE spent nuclear fuel storage cask and a conventional concrete storage cask in the areas of handling, transportation, and capital requirements. The DUCRETE cask is under evaluation as a new technology that could substantially reduce the overall costs of spent fuel and depleted U disposal. DUCRETE incorporates depleted U in a Portland cement mixture and functions as the cask`s primary radiation barrier. The cask system design includes insertion of the US DOE Multi-Purpose Canister inside the DUCRETE cask. The economic comparison is from the time a cask is loaded in a spent fuel pool until it is placed in the repository and includes the utility and overall US system perspectives.
Date: April 1, 1995
Creator: Powell, F.P.
Partner: UNT Libraries Government Documents Department

Comparing Candidate Hospital Report Cards

Description: We present graphical and analytical methods that focus on multivariate outlier detection applied to the hospital report cards data. No two methods agree which hospitals are unusually good or bad, so we also present ways to compare the agreement between two methods. We identify factors that have a significant impact on the scoring.
Date: December 31, 1997
Creator: Burr, T.L.; Rivenburgh, R.D.; Scovel, J.C. & White, J.M.
Partner: UNT Libraries Government Documents Department

Overview of catalyst testing and coprocessing studies at Sandia National Laboratories

Description: Prior to the initiation of Sandia`s fine particle size catalyst testing project, it was not feasible to compare the activities of the many direct coal liquefaction catalysts developed in various laboratories. This was due to the wide variety of testing methods used by the different catalyst developers. Sandia developed a procedure that uses a bituminous coal (DECS-17 Blind Canyon coal), phenathrene as the reaction solvent, and a factorial experimental design with three variables: temperature, time, and catalyst loading. Numerous catalysts have been evaluated. Pacific Northwest National Laboratories` (PNNL) 6-line ferrihydrite catalyst is the most active among the particulate catalysts. West Virginia University`s (WVU) iron catalyst impregnated on Blind Canyon coal is the best iron catalyst evaluated to date. Because this catalyst was prepared by impregnation, which involves several preparation steps, it cannot be directly compared to particulate catalysts. In an effort to enable this comparison, WVU produced a particulate iron catalyst that has been tested at Sandia. In addition, Sandia has also evaluated several of Argonne National Laboratory`s molybdenum and iron catalysts that were impregnated on Wyodak subbituminous coal from the Argonne Premium Coal Sample Program. Current activities are focused on developing capabilities for performing coprocessing experiments to support FETC`s coprocessing thrust and a new project aimed at helping Puerto Rico solve its waste disposal problems.
Date: October 1, 1997
Creator: Stohl, F.V.; Goodnow, D.C.; Diegert, K.V. & Andujar, L.
Partner: UNT Libraries Government Documents Department

Technical evaluation panel summary report: ceramic and glass immobilization options fissile materials disposition program

Description: This report documents the results of a technical evaluation of the merits of ceramic and glass immobilization forms for the disposition of surplus weapons-useable plutonium. The evaluation was conducted by a Technical Evaluation Panel (TEP), whose members were selected to cover a relevant range of scientific and technical expertise and represented each of the technical organizations involved in the Plutonium Immobilization Program. The TEP held a formal review at Lawrence Liver-more National Laboratory (LLNL) from July 2%August 1, 1997. Following this review, the TEP documented the review and its evaluation of the two immobilization technologies in this report to provide a technical basis for a recommendation by LLNL to the Department of Energy (DOE) for the preferred immobilization form. The comparison of the glass and ceramic forms and manufacturing processes was a tremendous challenge to the TEP. The two forms and their processes are similar in many ways. The TEP went to great effort to accurately assess what were, in many cases, fine details of the processes, unit operations, and the glass and ceramic forms themselves. The set of criteria used by the Fissile Materials Disposition Program (FMDP) in past screenings and down-selections was used to measure-the two options. One exception is that the TEP did not consider criteria that were largely nontechnical (namely international impact, public acceptance, and effects on other : DOE programs). The TEP� s measures and assessments are documented in detail. Care was taken to ensure that the data used were well documented and traceable to their source. Although no final conclusion regarding the preferred form was reached or explicitly stated in this report (this was not within the TEP� s charter), no �show stoppers� were identified for either form. Both forms appear capable of satisfying all the criteria, as interpreted by the TEP. The TEP ...
Date: December 23, 1997
Creator: Jostons, A; Armantrout, G; Brummond, W; Jantzen, CM; M; McKibben et al.
Partner: UNT Libraries Government Documents Department

Accelerator break-out group summary

Description: Interesting developments in accelerators have shown that they can be used as {open_quote}factory{close_quote}-type systems with the choice of technology dependent on the specific requirements of the application. The status and future possibilities for cyclotrons and linear accelerators are compared briefly, based on discussions at a break-out session on accelerators. Only high power systems with beam powers in excess of a MW average power were considered.
Date: December 31, 1996
Creator: Schriber, S.O. & Mandrillon, P.
Partner: UNT Libraries Government Documents Department

Compare harvest systems. Minnesota Agripower Project, Task II research report

Description: Our primary objectives for this task were to determine field performance and harvest losses for several types of cutting and baling equipment and to compare these values with those found in the literature. Originally, we had planned to study use of preservatives and their effect on harvest and storage losses, but since the MNVAP processing plant is not currently buying hay treated with preservatives, we did minimal work with preservatives during this phase of the project.
Date: October 30, 1997
Creator: Wilcke, W.F. & Hietala, J.S.
Partner: UNT Libraries Government Documents Department

Comparison of millimeter-wave cloud radar measurements for the Fall 1997 Cloud IOP

Description: One of the primary objectives of the Fall 1997 IOP was to intercompare Ka-band (350Hz) and W-band (95GHz) cloud radar observations and verify system calibrations. During September 1997, several cloud radars were deployed at the Southern Great Plains (SOP) Cloud and Radiation Testbed (CART) site, including the full time operation 35 GHz CART Millimeter-wave Cloud Radar (MMCR), the University of Massachusetts (UMass) single antenna 33GHz/95 GHz Cloud Profiling Radar System (CPRS), the 95 GHz Wyoming Cloud Radar (WCR) flown on the University of Wyoming King Air, the University of Utah 95 GHz radar and the dual-antenna Pennsylvania State University 94 GHz radar. In this paper the authors discuss several issues relevant to comparison of ground-based radars, including the detection and filtering of insect returns. Preliminary comparisons of ground-based Ka-band radar reflectivity data and comparisons with airborne radar reflectivity measurements are also presented.
Date: May 1, 1998
Creator: Sekelsky, S.M.; Li, L.; Galloway, J.; McIntosh, R.E.; Miller, M.A.; Clothiaux, E.E. et al.
Partner: UNT Libraries Government Documents Department

Some comments on manganin wire pressure gauges

Description: A standard manganin wire pressure gage was examined by comparing it with a recently developed 0.01% CaF/sub 2/ capacitive pressure gage. The effects of the Bridgman water kick'' and intrinsic time constant are clearly shown, and the results punctuate the usual assertion that manganin wire gages are extremely difficult to use approaching the 0.1% level. (auth)
Date: January 1, 1973
Creator: Andeen, C.; Schuele, D. & Fontanella, J.
Partner: UNT Libraries Government Documents Department

Global wind energy market report. Wind energy industry grows at steady pace, adds over 8,000 MW in 2003

Description: Cumulative global wind energy generating capacity topped 39,000 megawatts (MW) by the end of 2003. New equipment totally over 8,000 MW in capacity was installed worldwide during the year. The report, updated annually, provides information on the status of the wind energy market throughout the world and gives details on various regions. A listing of new and cumulative installed capacity by country and by region is included as an appendix.
Date: March 1, 2004
Creator: anon.
Partner: UNT Libraries Government Documents Department

Improving analytical understanding through the addition of information: Bayesian and hybrid mathematics approaches

Description: Safety analysts frequently must provide results that are based on sparse (or even no) data. When data (or more data) become available, it is important to utilize the new information optimally in improving the analysis results. Two methods for accomplishing this purpose are Bayesian analysis, where "prior" probability distributions are modified to become "posterior" distributions based on the new data, and hybrid (possibilistic/probabilistic analysis) where possibilistic "membership" portrays the subjectivity involved and the probabilistic analysis is "frequentist." Each of these approaches has interesting features, and it is advantageous to compare and contrast the two. In addition to describing and contrasting these two approaches, we will discuss how features of each can be combined to give new advantages neither offers by itself.
Date: September 13, 1998
Creator: Cooper, J.A. & Diegert, K.V.
Partner: UNT Libraries Government Documents Department

A comparison study on the densification behavior and mechanical properties of gelcast vs conventionally formed B{sub 4}C sintered conventionally and by microwaves

Description: The utilization of microwave energy for reaching high temperatures necessary to densify B{sub 4}C powder is compared with conventional means of sintering by evaluating the mechanical properties after densification. Microwave energy has been shown to be an effective means for achieving high sintered densities, even though temperatures of {approximately} 2,250 C are required. In this study, green preforms of B{sub 4}C specimens were sintered by both conventional and microwave heating. This study also utilized an advanced forming method called ``Gelcasting`` developed at ORNL. Gelcasting is a fluid forming process whereby high solids suspensions of powders containing dissolved monomers are cast into a mold, then polymerized or ``gelled`` in situ. This investigation compares microstructures and mechanical properties of both Gelcast B{sub 4}C and ``conventionally`` die-pressed B{sub 4}C. The microstructures and final mechanical properties of B{sub 4}C specimens are discussed.
Date: June 1, 1996
Creator: Menchhofer, P.A.; Kiggans, J.O.; Morrow, M.S. & Schechter, D.E.
Partner: UNT Libraries Government Documents Department

Beam coupling impedances of obstacles protruding into beam pipe

Description: The beam coupling impedances of small obstacles protruding inside the vacuum chamber of an accelerator are calculated analytically at frequencies for which the wavelength is large compared to a typical size of the obstacle. Simple formulas for a few important particular cases, including both essentially three-dimensional objects like a post or a mask and axisymmetric irises, are presented. The analytical results are compared and agree with three-dimensional computer simulations. These results allow simple practical estimates of the broad-band impedance contributions from such discontinuities.
Date: August 1, 1997
Creator: Kurennoy, S.S.
Partner: UNT Libraries Government Documents Department