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Combined Effect of Damping Screens and Streams Convergence on Turbulence

Description: Note presenting an analysis of the combined effect of a series of damping screens followed by an axisymmetric-stream convergence on the mean-square fluctuation-velocity intensities, scales, correlations, and one-dimensional spectra of a turbulence field convected by a main stream. Numerical results for the statistical quantities describing the turbulence field downstream of a screen-contraction configuration are obtained for the case of upstream isotropic turbulence.
Date: January 1953
Creator: Tucker, Maurice
Partner: UNT Libraries Government Documents Department

Screen-type noise reduction devices for ground running of turbojet engines

Description: Report presenting testing of the use of screens placed across the jet as a means of suppressing jet noise during ground running, which was somewhat offset by increased noise levels ahead of the engine. Air-jet tests showed negligible reduction in sound generation with additional screens. The large reductions obtained by using screens show that noise generated inside the engine by the turbine or combustion contribute only a minor part of the total noise.
Date: July 1957
Creator: Coles, Willard D. & North, Warren J.
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of Damping Screens

Description: From Summary: "The experimental investigation of damping screens described herein was undertaken primarily to test theories of the effects of damping screens and to obtain information on the performance of screens in oblique flow. The characteristics investigated include the damping of longitudinal and lateral components of turbulence, the effect of screens on scale, the conditions for the production of turbulence and eddies by screens, and the damping of spatial variations of mean speed."
Date: January 1950
Creator: Schubauer, G. B.; Spangenberg, W. G. & Klebanoff, P. S.
Partner: UNT Libraries Government Documents Department

Automating Pro/Engineer Using Trail Files and External Programs

Description: Keyboard macros provide shortcuts to many repetitive command sequences in Pro/Engineer. They map any number of frequently used command sequences to user-selected keyboard keys. They may be nested within each other and may also include user keyboard entry within the macro. Another powerful feature of Pro/Engineer is adding menu options. Menu options may be added to any Pro/Engineer menu and is an effective way to graphically display keyboard macros to make them more accessible. Command sequences are mapped to a single user-defined menu option added to the bottom of any Pro/Engineer window. The '{at}setbutton' command added to the 'menu{_}def.pro' file specifies the commands to associate with added menu options. Menu options may also be used to execute non-Pro/Engineer commands. The associated command is linked to a menu option within Pro/Engineer's Utilities menu (in the Misc menu) and is issued whenever the menu option is selected. Such a feature is useful for adding menu options to start the Pro/Engineer User Guide utility, start a text editor from within Pro/Engineer, or perform system level actions. The '{at}setbutton{_}exec' command is used in the 'menu{_}def.pro' file for non-Pro/Engineer commands. A more detailed description of adding menu options can be found in the Pro/Engineer Fundamentals Guide. Another useful component of Pro/Engineer is the trail file functionality. Trail files are automatically created every time a new working Pro/Engineer session begins. Although they are typically used to reconstruct a previous working session, they can also be used to automate a series of commands. By specifying all the commands in a trail file, a user can issue the commands quickly and repetitively using the command sequence 'Misc-Trail' and specifying the trail file name. All actions, including keyboard entries and mouse click locations, may be included in a trail file. Although adding menu options and using trial files provide ...
Date: May 21, 1996
Creator: Chow, K.
Partner: UNT Libraries Government Documents Department

Investigation of the Pressure-Loss Characteristics of the Westinghouse X24-C-2 Inlet Screen, TED No. NACA 0447

Description: At the request of the Bureau of Aeronautics, Navy Department, investigations of the static-pressure losses and total-head distributions of the Westinghouse X24-C-2 inlet screen were made in the induction aerodynamics laboratory at Langley. The screen was investigated in two configurations, both before and after rounding the leading edges of the vanes. Investigations were conducted through air flows up to about pounds per second.
Date: December 2, 1946
Creator: Lankford, John L.
Partner: UNT Libraries Government Documents Department

Foreign-object retention and flow characteristics of retractable engine-inlet screens

Description: Report presenting an investigation to determine and improve on the foreign-object-retention capabilities and pressure-loss characteristics of rectractable engine-inlet screens. Testing occurred with two commerically made retractable screens installed in the engine-inlet sections for which they were designed. Results regarding the retention for both the original and modified screens and pressure tests are provided.
Date: July 26, 1957
Creator: Steffen, Fred W. & Rodert, Lewis A.
Partner: UNT Libraries Government Documents Department

Survey of large protein complexes D. vulgaris reveals great structural diversity

Description: An unbiased survey has been made of the stable, most abundant multi-protein complexes in Desulfovibrio vulgaris Hildenborough (DvH) that are larger than Mr {approx} 400 k. The quaternary structures for 8 of the 16 complexes purified during this work were determined by single-particle reconstruction of negatively stained specimens, a success rate {approx}10 times greater than that of previous 'proteomic' screens. In addition, the subunit compositions and stoichiometries of the remaining complexes were determined by biochemical methods. Our data show that the structures of only two of these large complexes, out of the 13 in this set that have recognizable functions, can be modeled with confidence based on the structures of known homologs. These results indicate that there is significantly greater variability in the way that homologous prokaryotic macromolecular complexes are assembled than has generally been appreciated. As a consequence, we suggest that relying solely on previously determined quaternary structures for homologous proteins may not be sufficient to properly understand their role in another cell of interest.
Date: August 15, 2009
Creator: Han, B.-G.; Dong, M.; Liu, H.; Camp, L.; Geller, J.; Singer, M. et al.
Partner: UNT Libraries Government Documents Department

An Investigation of Screens for Removing Distortions in Ducted Flows at High Subsonic Speeds

Description: Report presenting an investigation of resistance screens for the purpose of obtaining uniform flow in ducts. The new screen designs consisted of several different screen shapes with the elements set at oblique angles (swept) to the flow. Results regarding a rectangular channel and diffuser investigation are provided.
Date: September 26, 1957
Creator: Wood, Charles C. & Knip, Gerald, Jr.
Partner: UNT Libraries Government Documents Department

Holographic Protection of Chronology in Universes of the Godel Type

Description: We analyze the structure of supersymmetric Godel-like cosmological solutions of string theory. Just as the original four-dimensional Godel universe, these solutions represent rotating, topologically trivial cosmologies with a homogeneous metric and closed timelike curves. First we focus on"phenomenological" aspects of holography, and identify the preferred holographic screens associated with inertial comoving observers in Godel universes. We find that holography can serve as a chronology protection agency: The closed timelike curves are either hidden behind the holographic screen, or broken by it into causal pieces. In fact, holography in Godel universes has many features in common with de Sitter space, suggesting that Godel universes could represent a supersymmetric laboratory for addressing the conceptual puzzles of de Sitter holography. Then we initiate the investigation of"microscopic" aspects of holography of Godel universes in string theory. We show that Godel universes are T-dual to pp-waves, and use this fact to generate new Godel-like solutions of string and M-theory by T-dualizing known supersymmetric pp-wave solutions.
Date: December 7, 2002
Creator: Boyda, Edward; Ganguli, Surya; Horava, Petr & Varadarajan, Uday
Partner: UNT Libraries Government Documents Department

Effectiveness of a turbojet tubular combustor in screening the turbine from foreign objects

Description: Report presenting the effectiveness of a tubular combustor in screening the turbine from foreign objects measured with air flow corresponding to that at static sea-level rated operation. On average, the effectiveness of the production combustor was only 36 percent for the foreign objects introduced in the tests; that is, 64 percent of the objects penetrated the combustor. Results for six different configurations are provided.
Date: July 18, 1955
Creator: Chiarito, Patrick T.
Partner: UNT Libraries Government Documents Department

The ARM Southern Great Plains Central Facility Best Estimate Radiative Flux CD

Description: The BEFlux VAP directly compares data from the three Normal Incidence Perheliometers, shaded pyranometers, and shaded pyrgeometers at the SGP CF. Extensive analysis with several years of data has produced limits of typical ranges of agreement when these instruments are performing as expected. These limits are used to screen the data, and then the average is taken of the two that agree best, given that at least two instruments agree to within the established limits. This is done for the downwelling direct normal and diffuse shortwave, and the downwelling longwave. The total (global) downwelling shortwave is then the sum of the direct and diffuse components.
Date: April 1, 2002
Creator: Long, CN
Partner: UNT Libraries Government Documents Department

Investigation of the pressure-loss characteristics of a turbojet inlet screen

Description: Report presenting the results of an investigation to determine the static-pressure losses and total-pressure distributions of a turbojet inlet screen. The screen was tested in two configurations: one with the vane leading edges square and rough and the other with the vane leading edges rounded. Results regarding the static-pressure-loss coefficient, corrected static-pressure loss, and total-pressure distributions are provided.
Date: September 1947
Creator: Lankford, John L.
Partner: UNT Libraries Government Documents Department

User's Manual Frac-Explore 2.0

Description: FRAC-EXPLORE 2.0, a new computer software package for oil and gas exploration using surface lineament and fracture analysis. FRAC-EXPLORE 2.0 provides a suite of tools for analyzing the characteristics and patterns of surface lineaments and fractures, as well as other surface geological features. These tools help identify priority areas of potential subsurface oil and gas traps. The package can be used in a frontier basin to initially screen the priority locations for further seismic and/or geochemical surveys. It can also be used in a mature basin to help delineate additional oil and gas reservoirs.
Date: March 9, 1999
Creator: George, S.A. & Guo, Genliang
Partner: UNT Libraries Government Documents Department

Proposal for an aluminum beam screen in the LHC

Description: This paper proposes a cold beam screen made of high strength, high electrical resistivity aluminum alloy (such as A7NOl) as an alternative to the present LHC design that is based on a copper co- laminated high Mn content stainless steel. The main advantages of an aluminum screen are: simple manufacturing processes, low cost, elimination of millions of small slots and of TEM waves, no adhesion problem, no helium leak problem (vacuum tight), non-magnetic, and others. The available aperture is equivalent to the present design when a non-uniform wall thickness is adopted. A prototype was built to demonstrate the design and the end connections. Concerns about the multi-pactoring, electron cloud instability, surface resistance and cryopumping using anodized aluminum will be addressed.
Date: June 1, 1997
Creator: Ishimaru, H.
Partner: UNT Libraries Government Documents Department

Volume visualization of multiple alignment of large genomicDNA

Description: Genomes of hundreds of species have been sequenced to date, and many more are being sequenced. As more and more sequence data sets become available, and as the challenge of comparing these massive ''billion basepair DNA sequences'' becomes substantial, so does the need for more powerful tools supporting the exploration of these data sets. Similarity score data used to compare aligned DNA sequences is inherently one-dimensional. One-dimensional (1D) representations of these data sets do not effectively utilize screen real estate. As a result, tools using 1D representations are incapable of providing informatory overview for extremely large data sets. We present a technique to arrange 1D data in 3D space to allow us to apply state-of-the-art interactive volume visualization techniques for data exploration. We demonstrate our technique using multi-millions-basepair-long aligned DNA sequence data and compare it with traditional 1D line plots. The results show that our technique is superior in providing an overview of entire data sets. Our technique, coupled with 1D line plots, results in effective multi-resolution visualization of very large aligned sequence data sets.
Date: July 25, 2005
Creator: Shah, Nameeta; Dillard, Scott E.; Weber, Gunther H. & Hamann, Bernd
Partner: UNT Libraries Government Documents Department

Walla Walla River Basin Fish Screen Evaluations; Nursery Bridge Fishway, Garden City/Lowden II, and Little Walla Walla Sites, 2004 Annual Report.

Description: Pacific Northwest National Laboratory evaluated the fish screens at the Nursery Bridge Fishway, the Garden City/Lowden II site west of Walla Walla, Washington, and the Little Walla Walla site in Milton-Freewater, Oregon, in the Walla Walla River Basin during 2004. The fish-screen facilities were examined to determine if they were being effectively operated and maintained to provide for safe fish passage. At the Nursery Bridge Fishway, the screens were evaluated specifically to determine whether the louvers that aid in controlling water flow from behind the screens could be adjusted so that the screens would meet fish-protection criteria. Data were collected to determine whether velocities in front of the screens met current National Oceanic and Atmospheric Administration's National Marine Fisheries Service (NOAA Fisheries) (formerly NMFS) criteria to promote safe and timely fish passage before and after changing the louver settings. The Little Walla Walla screens were evaluated to determine how a build-up of algae on the screens affected water velocities.
Date: November 1, 2004
Creator: Vucelick, J. & McMichael, G.
Partner: UNT Libraries Government Documents Department

Action-Oriented Benchmarking: Concepts and Tools

Description: Most energy benchmarking tools provide static feedback on how one building compares to a larger set of loosely similar buildings, without providing information at the end-use level or on what can be done to reduce consumption, cost, or emissions. In this article--Part 1 of a two-part series--we describe an 'action-oriented benchmarking' approach, which extends whole-building energy benchmarking to include analysis of system and component energy use metrics and features. Action-oriented benchmarking thereby allows users to generate more meaningful metrics and to identify, screen and prioritize potential efficiency improvements. This opportunity assessment process can then be used to inform and optimize a full-scale audit or commissioning process. We introduce a new web-based action-oriented benchmarking system and associated software tool-EnergyIQ. The benchmarking methods, visualizations, and user interface design are informed by an end-user needs assessment survey and best-practice guidelines from ASHRAE.
Date: February 13, 2008
Creator: Commission, California Energy; Mathew, Paul; Mills, Evan; Mathew, Paul; Piette, Mary Ann; Bourassa, Norman et al.
Partner: UNT Libraries Government Documents Department


Description: Bellows are frequently required in accelerators and colliders. Usually RF-shields with spring fingers are employed to screen the bellows. The lack of accessibility in cryogenic systems can be a problem and asks for alternate solutions to eliminate possible overheating, sparking, etc that occurred in intensive beams. This note addresses an alternate kind of RF shield, which uses capacitive contact instead of mechanical contact. The analysis, as well as numerical example of a superconducting cavity structure, shows that the capacitive RF shield satisfies the impedance requirements of both beam and HOMs. The capability of thermal isolation is also analyzed.
Date: March 24, 2004
Creator: ZHAO,Y. HAHN,H.
Partner: UNT Libraries Government Documents Department

[TV screen in studio]

Description: Photograph of a television screen in a TV studio. The screen reads "WBAP-TV, Fort Worth Star Telegram, Channel 5".
Date: February 2, 1950
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections