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A flight investigation and analysis of the lateral-oscillation characteristics of an airplane

Description: Report presenting flight tests to determine the causes of undesirable dynamic lateral-stability characteristics of an airplane. Various rudder modifications were flight tested with the rudder free and fixed over an indicated airspeed range from approximately 200 to 450 miles per hour. Results regarding rudder-fixed characteristics and rudder-free characteristics are provided.
Date: October 1950
Creator: Stough, Carl J. & Kauffman, William M.
Partner: UNT Libraries Government Documents Department

A flight investigation and analysis of the lateral-oscillation characteristics of an airplane

Description: Report presenting flight tests to determine the causes of undesirable dynamic lateral-stability characteristics of an airplane. Various rudder modifications were flight tested with the rudder free and fixed over an indicated airspeed range from approximately 200 to 450 miles per hour. Results regarding rudder-fixed characteristics and rudder-free characteristics are provided.
Date: June 3, 1948
Creator: Stough, Carl J. & Kauffman, William M.
Partner: UNT Libraries Government Documents Department

Wind-Tunnel Investigation of the Effects of Various Asymmetric Canopy Modifications on the Behavior of Descending Parachutes

Description: Report presenting an investigation in the free-spinning tunnel to study the behavior in descent of hemispherical and quasi-conical parachutes, some with symmetrical canopy modifications and all with a right circular cylinder suspended by one end below the parachute. Results indicated that a lateral flight component during descent could be obtained by using a circular cutout in the side of the canopy of a hemispherical parachute and a large slit between two panels of a quasi-conical parachute.
Date: February 15, 1952
Creator: Scher, Stanley H.
Partner: UNT Libraries Government Documents Department

A Transonic Wind-Tunnel Investigation of the Effect of Modifications to an Indented Body in Combination With a 45 Degree Sweptback Wing

Description: Memorandum presenting an investigation of modifications to an indented body which was originally designed on the basis of the transonic drag-rise rule to determine the effects on the aerodynamic characteristics of a 45 degree sweptback-wing-body combination. The investigation covered a range of Mach numbers and angles of attack. Results regarding lift, drag for the nonlifting case, drag for the lifting case, maximum lift-to-drag ratios, and pitching moment are provided.
Date: September 22, 1953
Creator: Loving, Donald L.
Partner: UNT Libraries Government Documents Department

Wind-Tunnel Investigation of the Characteristics of Blunt-Nose Ailerons on a Tapered Wing

Description: Characteristics are determined for various modifications of 0.155-chord blunt-nose aileron on semispan model of tapered fighter plane wing. Ailerons with 40 percent nose balance reduced high-speed stick forces. Increased balance chord increases effectiveness and reduces high-speed stick forces. Increased balance chord increases effectiveness and reduces adverse effects of gap at aileron hose. Increase of nose radii increased negative slope of curve hinge-movement coefficient plotted against deflection. Extended deflection range decreased aileron effectiveness for small deflections but increased it at large deflections. Peak pressures at noses of ailerons are relatively high at moderate deflections.
Date: February 1943
Creator: Purser, Paul E. & Toll, Thomas A.
Partner: UNT Libraries Government Documents Department

Investigation of Ejection Releases of an MB-1 Rocket From a 0.04956-Scaled Model of the Convair F-106A Airplane at Several Mach Numbers and Simulated Attitudes : Coord. No. AF-AM-57

Description: Memorandum presenting a study of fin modifications as a continuation of an investigation of the ejection release characteristics of an internally carried MB-1 rocket in the Convair F-106A airplane. The rocket was ejected with fins open, fins closed, fins closed with a shroud between the fins, and fins folded with a "boattail" placed in between the fins. Ejections at three different Mach numbers, and a comparison of the results at supersonic and subsonic Mach numbers are provided.
Date: September 17, 1957
Creator: Lee, John B. & Basford, Robert C.
Partner: UNT Libraries Government Documents Department

Data From Large-Scale Low-Speed Tests of Airplane Configurations With a Thin 45 Degree Swept-Wing Incorporating Several Leading-Edge Contour Modifications

Description: Memorandum presenting force tests that have been made of airplane configurations with a thin swept wing incorporating several wing-contour modifications forward of maximum thickness. Both longitudinal and lateral characteristics are provided.
Date: May 7, 1956
Creator: Evans, William T.
Partner: UNT Libraries Government Documents Department

User's Guide for Hysteretic Capillary Pressure and Relative Permeability Functions in iTOUGH2

Description: The precursor of TOUGH2, TOUGH, was originally developed with non-hysteretic characteristic curves. Hysteretic capillary pressure functions were implemented in TOUGH in the late 1980s by Niemi and Bodvarsson (1988), and hysteretic capillary pressure and relative permeability functions were added to iTOUGH2 about ten years later by Finsterle et al. (1998). Recently, modifications were made to the iTOUGH2 hysteretic formulation to make it more robust and efficient (Doughty, 2007). Code development is still underway, with the ultimate goal being a hysteretic module that fits into the standard TOUGH2 (Pruess et al., 1991) framework. This document provides a user's guide for the most recent version of the hysteretic code, which runs within iTOUGH2 (Finsterle, 1999a,b,c). The current code differs only slightly from what was presented in Doughty (2007), hence that document provides the basic information on the processes being modeled and how they are conceptualized. This document focuses on a description of the user-specified parameters required to run hysteretic iTOUGH2. In the few instances where the conceptualization differs from that of Doughty (2007), the features described here are the current ones. Sample problems presented in this user's guide use the equation-of-state module ECO2N (Pruess, 2005). The components present in ECO2N are H{sub 2}O, NaCl, and CO{sub 2}. Two fluid phases and one solid phase are considered: an aqueous phase, which primarily consists of liquid H2O and may contain dissolved NaCl and CO{sub 2}; a supercritical phase which primarily consists of CO{sub 2}, but also includes a small amount of gaseous H{sub 2}O; and a solid phase consisting of precipitated NaCl. Details of the ECO2N formulation may be found in Pruess (2005). The aqueous phase is the wetting phase and is denoted ''liquid'', whereas the supercritical phase is the non-wetting phase and is denoted ''gas''. The hysteretic formalism may be applied to other ...
Date: August 1, 2009
Creator: Doughty, C.A.
Partner: UNT Libraries Government Documents Department

Effect of Several Modifications to Center Body and Cowling on Supercritical Performance of a Supersonic Inlet at Mach Number of 2.02

Description: Report discussing an investigation of several modifications of the center body and cowling of a supersonic inlet at Mach number 2.02 and angles of attack up to 12.25 degrees. Information about the effect on stable range of boundary-layer control on the center body, the stable range of distortion of conical shock, and the stable range of cowling-lip thickness is provided.
Date: May 20, 1955
Creator: Trimpi, Robert L. & Cohen, Nathaniel B.
Partner: UNT Libraries Government Documents Department

Predictions of Elliptic flow and nuclear modification factor from 200 GeV U+U collisions at RHIC

Description: Predictions of elliptic flow (v{sub 2}) and nuclear modification factor (R{sub AA}) are provided as a function of centrality in U + U collisions at {radical}s{sub NN} = 200 GeV. Since the {sup 238}U nucleus is naturally deformed, one could adjust the properties of the fireball, density and duration of the hot and dense system, for example, in high energy nuclear collisions by carefully selecting the colliding geometry. Within our Monte Carlo Glauber based approach, the v{sub 2} with respect to the reaction plane v{sub 2}{sup RP} in U + U collisions is consistent with that in Au + Au collisions, while the v{sub 2} with respect to the participant plane v{sub 2}{sup PP} increases {approx}30-60% at top 10% centrality which is attributed to the larger participant eccentricity at most central U + U collisions. The suppression of R{sub AA} increases and reaches {approx}0.1 at most central U + U collisions that is by a factor of 2 more suppression compared to the central Au + Au collisions due to large size and deformation of Uranium nucleus.
Date: July 7, 2010
Creator: Masui, Hiroshi; Mohanty, Bedangadas & Xu, Nu
Partner: UNT Libraries Government Documents Department

SIGNALING TO THE P53 TUMOR SUPPRESSOR THROUGH PATHWAYS ACTIVATED BY GENOTOXIC AND NON-GENOTOXIC STRESSES.

Description: The p53 tumor suppressor is a tetrameric transcription factor that is post-translational modified at {approx}18 different sites by phosphorylation, acetylation, or sumoylation in response to various cellular stress conditions. Specific posttranslational modifications, or groups of modifications, that result from the activation of different stress-induced signaling pathways are thought to modulate p53 activity to regulate cell fate by inducing cell cycle arrest, apoptosis, or cellular senescence. Here we review the posttranslational modifications to p53 and the pathways that produce them in response to both genotoxic and non-genotoxic stresses.
Date: July 1, 2002
Creator: ANDERSON,C. W. APPELLA,E.
Partner: UNT Libraries Government Documents Department

Root status and future developments

Description: In this talk the authors review the major additions and improvements made to the ROOT system in the last 18 months and present their plans for future developments. The additions and improvements range from modifications to the I/O sub-system to allow users to save and restore objects of classes that have not been instrumented by special ROOT macros, to the addition of a geometry package designed for building, browsing, tracking and visualizing detector geometries. Other improvements include enhancements to the quick analysis sub-system (TTree::Draw()), the addition of classes that allow inter-file object references (TRef, TRefArray), better support for templates and STL classes, amelioration of the Automatic Script Compiler and the incorporation of new fitting and mathematical tools. Efforts have also been made to increase the modularity of the ROOT system with the introduction of more abstract interfaces and the development of a plug-in manager. In the near future, they intend to continue the development of PROOF and its interfacing with GRID environments. They plan on providing an interface between Geant3, Geant4 and Fluka and the new geometry package. The ROOT-GUI classes will finally be available on Windows and they plan to release a GUI inspector and builder. In the last year, ROOT has drawn the endorsement of additional experiments and institutions. It is now officially supported by CERN and used as key I/O component by the LCG project.
Date: October 1, 2003
Creator: al., Rene Brun et
Partner: UNT Libraries Government Documents Department

Preliminary shielding estimates for the proposed National ISOL Radioactive Ion Beam (RIB) Facility at Oak Ridge

Description: ORNL built a first-generation Radioactive Ion Beam (RIB) facility for astrophysics and nuclear physics research; it was named Holifield Radioactive Ion Beam Facility (HRIBF) and is based on the Isotope Separator On Line (ISOL) technique. Planning is underway for a second- generation facility, the National ISOL RIB facility at Oak Ridge; it will build on the existing HRIBF and may utilize many existing components and shielded areas. Preliminary upgrade plan for the new facility includes: adding a superconducting booster for the tandem accelerator; replacing the 1960-vintage, 60-MeV proton, 50-microamp ORIC (Oak Ridge Isochronous Cyclotron) with a modern 200-MeV proton, 200-microamp cyclotron; and building a high-power {sup 238}U fission target to accept the 200-MeV proton beam. This report summarizes the results of a preliminary 1-D shielding analysis of the proposed upgrade, to determine the shielding requirements for a 0.25 mrem/h dose rate at the external surface of the exclusion area. Steel shielding weights ranging from 60 to 100 metric tons, were considered manageable; these could be reduced by a factor of 2 to 3 if the orientation of the proposed target station was changed.
Date: October 1, 1996
Creator: Johnson, J.O.; Gabriel, T.A. & Lillie, R.A.
Partner: UNT Libraries Government Documents Department

The evolution of ANL CMT gloveboxes

Description: This report summarizes the following topics: the design approach based upon user-friendly concepts; utilization of existing component designs; cost effectiveness; schedule; and adaptable to project process changes without losing overall effectiveness of user-friendly approach.
Date: July 6, 2000
Creator: Malecha, R. F.; Frigo, A. A. & Preuss, D. E.
Partner: UNT Libraries Government Documents Department

Graphical interface for the physics-based generation of inputs to 3D MEEC SGEMP and SREMP simulations

Description: A graphical user interface (GUI) is under development for the MEEC family of SGEMP and SREMP simulation codes. These codes are workhorse legacy codes that have been in use for nearly two decades, with modifications and enhanced physics models added throughout the years. The MEEC codes are currently being evaluated for use by the DOE in the Dual Revalidation program and experiments at NIF. The new GUI makes the codes more accessible and less prone to input errors by automatically generating the parameters and grids that previously had to be designed by hand. physics-based algorithms define the simulation volume with expanding meshes. Users are able to specify objects, materials, and emission surfaces through dialogs and input boxes. 3D and orthographic views are available to view objects in the volume. Zone slice views are available for stepping through the overlay of objects on the mesh in planes aligned with the primary axes.
Date: December 1, 1998
Creator: Bland, M; Wondra, J; Nunan, S & Walters, D
Partner: UNT Libraries Government Documents Department

Testing of the TriP Chip Running at 132 nsec Using a Modified AFE Board

Description: In this note we describe the first set of tests done with a sample of TriP chips that were mounted on a modified AFE board. The modifications consisted of different firmware and the replacement of one power supply switch. The board used was a standard AFEIc board (red type) on which new MCMs (MCMIIs) were mounted. The new MCMs were designed to support the TriP and emulate the SVX for readout when mounted on an AFEIc board. The TriP and the MCMs are described in Ref. [1]. Two versions of the MCMII were designed and built: one (MCMIIb) supports two TriP chips wirebonded directly to the MCM substrate. The other, (MCMIIc) supports one TriP which can be either wirebonded directly or packaged into a standard TQFP surface mount package. Due to space constraints, this MCM can support only 1 TriP. We tested 6 TriP chips on 3 different MCMIIb (MCMIIb-1, MCMIIb-2 and MCMIIb-3) and 2 other TriPs were tested on MCMIIc, one of them with an unpackaged TriP (MCMIIc-1) and the other with a packaged TriP (MCMIIc-2). A set of 10 programable internal registers control the TriP operation, the description of these registers can be found in [1]. Table 1 shows the values used for the tests described in this note. In Ref. [1] there is a description of the signals that are needed to operate the TriP chip. We implemented in a Field Programable Gate Array (FPGA), also part of the MCM, a set of shift registers that allow us to download via the 1553 interface to the AFE board, any desired timing for the signals that the FPGA has to send to the TriP chip. These registers are run with a 121.21 MHz clock (which is 16x the crossing clock and phase locked to it), which means that ...
Date: December 19, 2003
Creator: al., Juan Estrada et
Partner: UNT Libraries Government Documents Department

The effect of negative dihedral, tip droop, and wing-tip shape on the low-speed aerodynamic characteristics of a complete model having a 45 degrees sweptback wing

Description: "An investigation has been conducted in the Langley 300 MPH 7- by 10-foot tunnel to determine the effect of negative dihedral, tip droop, and wing-tip shape on the low-speed aerodynamic characteristics of a complete model having a 45 degrees sweptback wing. Longitudinal and lateral stability characteristics were obtained for the model with and without tail surfaces" (p .1).
Date: December 6, 1948
Creator: Spearman, M. Leroy & Becht, Robert E.
Partner: UNT Libraries Government Documents Department

Effects of several leading-edge modifications on the stalling characteristics of a 45 degree swept-forward wing

Description: Report presenting an investigation to determine the effects of several leading-edge modifications on the maximum lift and pitching-moment characteristics on a large-scale 45 degree swept-forward wing. A full-span leading-edge flap deflected 30 degrees down tended to give the largest gain of maximum lift. Results regarding the plain leading-edge flaps and cambered nose are explored.
Date: June 14, 1949
Creator: McCormack, Gerald M. & Cook, Woodrow L.
Partner: UNT Libraries Government Documents Department

Flight investigation of the effects of a partial-span leading-edge chord extension on the aerodynamic characteristics of a 35 degree swept-wing fighter airplane

Description: Report presenting a flight investigation to evaluate the effects of a partial-span, 15-percent-chord, leading-edge extension on the aerodynamic characteristics of the F-86A airplane. Results regarding the longitudinal stability, low-speed stalls, drag, and pilot reports are provided.
Date: April 23, 1954
Creator: Matteson, Frederick H. & Van Dyke, Rudolph D., Jr.
Partner: UNT Libraries Government Documents Department

Effects of various modifications on the static longitudinal stability and control characteristics of a 0.065-scale model of the Chance Vought Regulus II missile at a Mach number of 2.01: TED No. NACA AD 398

Description: Report presenting an investigation in the 4- by 4-foot supersonic pressure tunnel to determine the effects on the static longitudinal stability and control characteristics of various modifications to a 0.065-scale model of the Chance Vought Regulus II missile. Some of the modifications included control housing on top of the fuselage, two sizes of canard surfaces with fixed incidence angles, various angles of nose droop, and two types of inlet boundary-layer bleed diverters.
Date: September 26, 1955
Creator: Robinson, Ross B. & Driver, Cornelius
Partner: UNT Libraries Government Documents Department

Effects of modifications to the leading-edge region on the stalling characteristics of the NACA 63(sub 1)-012 airfoil section

Description: Report presenting a wind-tunnel investigation of a series of modifications to the leading-edge region of the NACA 63(sub 1)-012 airfoil section to determine the possibilities of delaying the flow separation that occurs near the leading edge of the basic section and improving the stalling characteristics. Results regarding the effect of the leading-edge modifications and effect of leading-edge flap are provided.
Date: November 1950
Creator: Kelly, John A.
Partner: UNT Libraries Government Documents Department

General MoM Solutions for Large Arrays

Description: This paper focuses on a numerical procedure that addresses the difficulties of dealing with large, finite arrays while preserving the generality and robustness of full-wave methods. We present a fast method based on approximating interactions between sufficiently separated array elements via a relatively coarse interpolation of the Green's function on a uniform grid commensurate with the array's periodicity. The interaction between the basis and testing functions is reduced to a three-stage process. The first stage is a projection of standard (e.g., RWG) subdomain bases onto a set of interpolation functions that interpolate the Green's function on the array face. This projection, which is used in a matrix/vector product for each array cell in an iterative solution process, need only be carried out once for a single cell and results in a low-rank matrix. An intermediate stage matrix/vector product computation involving the uniformly sampled Green's function is of convolutional form in the lateral (transverse) directions so that a 2D FFT may be used. The final stage is a third matrix/vector product computation involving a matrix resulting from projecting testing functions onto the Green's function interpolation functions; the low-rank matrix is either identical to (using Galerkin's method) or similar to that for the bases projection. An effective MoM solution scheme is developed for large arrays using a modification of the AIM (Adaptive Integral Method) method. The method permits the analysis of arrays with arbitrary contours and nonplanar elements. Both fill and solve times within the MoM method are improved with respect to more standard MoM solvers.
Date: July 22, 2003
Creator: Fasenfest, B; Capolino, F; Wilton, D R; Jackson, D R & Champagne, N
Partner: UNT Libraries Government Documents Department

Probing Late Neutrino Mass Properties With SupernovaNeutrinos

Description: Models of late-time neutrino mass generation contain new interactions of the cosmic background neutrinos with supernova relic neutrinos (SRNs). Exchange of an on-shell light scalar may lead to significant modification of the differential SRN flux observed at earth. We consider an Abelian U(1) model for generating neutrino masses at low scales, and show that there are cases for which the changes induced in the flux allow one to distinguish the Majorana or Dirac nature of neutrinos, as well as the type of neutrino mass hierarchy (normal or inverted or quasi-degenerate). In some region of parameter space the determination of the absolute values of the neutrino masses is also conceivable. Measurements of the presence of these effects may be possible at the next-generation water Cerenkov detectors enriched with Gadolinium, or a 100 kton liquid argon detector.
Date: August 8, 2007
Creator: Baker, Joseph; Goldberg, Haim; Perez, Gilad & Sarcevic, Ina
Partner: UNT Libraries Government Documents Department