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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 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 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

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

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

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

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

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

Translating the cancer genome: Going beyond p values

Description: Cancer cells are endowed with diverse biological capabilities driven by myriad inherited and somatic genetic and epigenetic aberrations that commandeer key cancer-relevant pathways. Efforts to elucidate these aberrations began with Boveri's hypothesis of aberrant mitoses causing cancer and continue today with a suite of powerful high-resolution technologies that enable detailed catalogues of genomic aberrations and epigenomic modifications. Tomorrow will likely bring the complete atlas of reversible and irreversible alteration in individual cancers. The challenge now is to discern causal molecular abnormalities from genomic and epigenomic 'noise', to understand how the ensemble of these aberrations collaborate to drive cancer pathophysiology. Here, we highlight lessons learned from now classical examples of successful translation of genomic discoveries into clinical practice, lessons that may be used to guide and accelerate translation of emerging genomic insights into practical clinical endpoints that can impact on practice of cancer medicine.
Date: April 3, 2008
Creator: Chin, Lynda; Chin, Lynda & Gray, Joe W.
Partner: UNT Libraries Government Documents Department

Probing the Geometry of Warped String Compactifications at the LHC

Description: Warped string compactifications, characterized by the nonsingular behavior of the metric in the infrared (IR), feature departures from the usual anti?de Sitter warped extra dimensions. We study the implications of the smooth IR cutoff for Randall-Sundrum- (RS-)type models. We find that the phenomenology of the Kaluza-Klein gravitons (including their masses and couplings) depends sensitively on the precise shape of the warp factor in the IR. In particular, we analyze the warped deformed conifold, find that the spectrum differs significantly from that of RS, and present a simple prescription (a mass-gap ansatz) that can be used to study the phenomenology of IR modifications to 5D warped extra dimensions.
Date: May 28, 2007
Creator: Walker, Devin; Shiu, Gary; Underwood, Bret; Zurek, Kathryn M. & Walker, Devin G. E.
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

Automated Structure Solution with the PHENIX Suite

Description: Significant time and effort are often required to solve and complete a macromolecular crystal structure. The development of automated computational methods for the analysis, solution and completion of crystallographic structures has the potential to produce minimally biased models in a short time without the need for manual intervention. The PHENIX software suite is a highly automated system for macromolecular structure determination that can rapidly arrive at an initial partial model of a structure without significant human intervention, given moderate resolution and good quality data. This achievement has been made possible by the development of new algorithms for structure determination, maximum-likelihood molecular replacement (PHASER), heavy-atom search (HySS), template and pattern-based automated model-building (RESOLVE, TEXTAL), automated macromolecular refinement (phenix.refine), and iterative model-building, density modification and refinement that can operate at moderate resolution (RESOLVE, AutoBuild). These algorithms are based on a highly integrated and comprehensive set of crystallographic libraries that have been built and made available to the community. The algorithms are tightly linked and made easily accessible to users through the PHENIX Wizards and the PHENIX GUI.
Date: June 9, 2008
Creator: Zwart, Peter H.; Zwart, Peter H.; Afonine, Pavel; Grosse-Kunstleve, Ralf W.; Hung, Li-Wei; Ioerger, Tom R. et al.
Partner: UNT Libraries Government Documents Department

Iterative build OMIT maps: Map improvement by iterative model-building and refinement without model bias

Description: A procedure for carrying out iterative model-building, density modification and refinement is presented in which the density in an OMIT region is essentially unbiased by an atomic model. Density from a set of overlapping OMIT regions can be combined to create a composite 'Iterative-Build' OMIT map that is everywhere unbiased by an atomic model but also everywhere benefiting from the model-based information present elsewhere in the unit cell. The procedure may have applications in the validation of specific features in atomic models as well as in overall model validation. The procedure is demonstrated with a molecular replacement structure and with an experimentally-phased structure, and a variation on the method is demonstrated by removing model bias from a structure from the Protein Data Bank.
Date: February 12, 2008
Creator: Los Alamos National Laboratory, Mailstop M888, Los Alamos, NM 87545, USA; Lawrence Berkeley National Laboratory, One Cyclotron Road, Building 64R0121, Berkeley, CA 94720, USA; Department of Haematology, University of Cambridge, Cambridge CB2 0XY, England; Terwilliger, Thomas; Terwilliger, T.C.; Grosse-Kunstleve, Ralf Wilhelm et al.
Partner: UNT Libraries Government Documents Department

Constraints and Casimirs for Super Poincare and Supertranslation Algebras in various dimensions

Description: We describe, for arbitrary dimensions the construction of a covariant and supersymmetric constraint for the massless Super Poincare algebra and we show that the constraint fixes uniquely the representation of the algebra. For the case of finite mass and in the absence of central charges we discuss a similar construction, which generalizes to arbitrary dimensions the concept of the superspin Casimir. Finally we discuss briefly the modifications introduced by central charges, both scalar and tensorial.
Date: November 3, 2004
Creator: Zumino, Bruno
Partner: UNT Libraries Government Documents Department

Effect of size heterogeneity on community identification in complex networks

Description: Identifying community structure can be a potent tool in the analysis and understanding of the structure of complex networks. Up to now, methods for evaluating the performance of identification algorithms use ad-hoc networks with communities of equal size. We show that inhomogeneities in community sizes can and do affect the performance of algorithms considerably, and propose an alternative method which takes these factors into account. Furthermore, we propose a simple modification of the algorithm proposed by Newman for community detection (Phys. Rev. E 69 066133) which treats communities of different sizes on an equal footing, and show that it outperforms the original algorithm while retaining its speed.
Date: January 1, 2008
Creator: Danon, L.; Diaz-Guilera, A. & Arenas, A.
Partner: UNT Libraries Government Documents Department


Description: The collaborative development of an optimised cavity/cryomodule solution for application on ERL facilities has now progressed to final assembly and testing of the cavity string components and their subsequent cryomodule integration. This paper outlines the verification of the various cryomodule sub-components and details the processes utilised forfinal cavity string integration. The paper also describes the modifications needed to facilitate this new cryomodule installation and ultimate operation on the ALICE facility at Daresbury Laboratory.
Date: April 29, 2009
Creator: McIntosh, P. A.; Bate, R.; Beard, C. D.; Cordwell, M. A.; Dykes, D. M.; Pattalwar, S. M. et al.
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

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