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Effects of nose angle and Mach number on transition on cones at supersonic speeds

Description: "An investigation has been made to determine the transition characteristics of a group of smooth, sharp-nosed cones varying from 10 degrees to sixty degrees in included apex angle over a Mach number range from 1.61 to 2.20 and a range of Reynolds number per foot from about 1.5 x 10 to the 6th power to 8 x 10 to the 6th power. Increasing the cone angle is shown to decrease slightly the transition Reynolds number, whereas the effects of changes of Mach number and unit Reynolds number are negligible. When transition occurred within 15 to 20 percent of the model length from the base there was a dropoff in transition Reynolds number" (p. 1).
Date: September 1958
Creator: Czarnecki, K. R. & Jackson, Mary W.
Partner: UNT Libraries Government Documents Department

Some experimental heating data on convex and concave hemispherical nose shapes and hemispherical depressions on a 30-degree blunted nose cone

Description: Report discussing heat data obtained on concave and convex hemispherical nose shapes and hemispherical depressions on a blunted 30-degree nose cone at a variety of Mach numbers. Both hot-jet tests and flight tests were carried out.
Date: March 10, 1958
Creator: Hopko, Russell N. & Strass, H. Kurt
Partner: UNT Libraries Government Documents Department

Supersonic Flow Around Circular Cones at Angles of Attack

Description: Note presenting an analysis of the flow around cones without axial symmetry and moving at supersonic velocity. The results of the analysis are applied to the determination of flow around circular cones at small angles of attack. It is shown that good agreement with experimental results can be obtained from the first-order theory if the complete equation for the pressure distribution is used.
Date: November 1950
Creator: Ferri, Antonio
Partner: UNT Libraries Government Documents Department

On Point Designs for High Gain Fast Ignition

Description: Fast ignition research has reached the stage where point designs are becoming crucial to the identification of key issues and the development of projects to demonstrate high gain fast ignition. The status of point designs for cone coupled electron fast ignition and some of the issues they highlight are discussed.
Date: September 27, 2007
Creator: Key, M; Akli, K; Beg, F; Betti, R; Clark, D S; Chen, S N et al.
Partner: UNT Libraries Government Documents Department

Limited heat-transfer, drag, and stability results from an investigation at Mach numbers up to 9 of a large rocket-propelled 10 degree cone

Description: Report presenting information on the heat transfer, drag, and stability of a large rocket-propelled 10 degree cone in a flight test. The location of turbulent flow was noted and the measured drag coefficients at several locations on the cone are provided.
Date: July 22, 1957
Creator: Hall, James R. & Speegle, Katherine C.
Partner: UNT Libraries Government Documents Department

The use of cones as stabilizing and control surfaces at hypersonic speeds

Description: Report discussing the use of cones as stabilizing and control surfaces, which seems to be promising. Information about preliminary considerations, range of cone angles of probable interest, effects of Mach number on the shift in lift advantage from flat plate to cone, comparison of cone with more competitive lifting surfaces, and comparison in terms of producing the same restoring force for complete configuration is presented.
Date: August 12, 1957
Creator: Love, Eugene S.
Partner: UNT Libraries Government Documents Department

Hypersonic Viscous Flow Over Slender Cones

Description: Note presenting viscous self-induced pressures on 3 degree semivertex angle cones measured over a free-stream Mach number range and viscous-interaction parameter range. Results regarding the experiment, comparison between theory and experiment, and hole-size effect are provided.
Date: September 1958
Creator: Talbot, Lawrence; Koga, Toyoki & Sherman, Pauline M.
Partner: UNT Libraries Government Documents Department

Plan of Study for the Northern Atlantic Coastal Plain Regional Aquifer System Analysis

Description: Abstract: Sediments of Cretaceous to Holocene age compose the Northern Atlantic Coastal Plain aquifer system in an area of 50,000 square miles from North Carolina to New York. The aquifer system is the principal source of water supply for most of the area. About 1.4 billion gallons are withdrawn each day. Increasing pumpage has create~ problems such as declining water levels, saltwater intrusion, and land subsidence. The U.S. Geological Survey has begun a comprehensive study of the aquifer system that will define the geology, hydrology, and geochemistry of the system. The effects of future utilization of the aquifer system will be determined and alternative water withdrawal plans will be evaluated through computer simulation modeling. This report describes the objectives, organization, and work plans of the study.
Date: April 1980
Creator: Meisler, Harold
Partner: UNT Libraries Government Documents Department

Study of Open Jet Wind Tunnel Cones

Description: "Tests have been made by the National Advisory Committee for Aeronautics on the air flow in an open jet wind tunnel with various sizes, shapes, and spacings of cones, and the flow studied by means of velocity and direction surveys in conjunction with flow pictures. It was found that for all combinations of cones tested the flow is essentially the same, consisting of an inner core of decreasing diameter having uniform velocity and direction, and a boundary layer of more or less turbulent air increasing in thickness with length of jet. The energy ratio of the tunnel was obtained for the different combinations of cones, and the spilling around the exit cone causing undesirable air currents in the experiment chamber was noted" (p. 1).
Date: August 1927
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department

Experimental Drag Coefficients of Round Noses With Conical Windshields at Mach Number 2.72

Description: "An exploratory investigation at Mach number 2.72 has been made to show the decrease in the drag of a round-nose model achieved by mounting a small cone on a rod ahead of the nose. The geometric parameters which were varied were the cone-base diameter, cone angle, and rod length. All models showed large decreases in drag compared to that of the round nose alone" (p. 1).
Date: June 28, 1955
Creator: Jones, Jim J.
Partner: UNT Libraries Government Documents Department

Nail-like targets for laser plasma interaction experiments

Description: The interaction of ultra-high power picosecond laser pulses with solid targets is of interest both for benchmarking the results of hybrid particle in cell (PIC) codes and also for applications to re-entrant cone guided fast ignition. We describe the construction of novel targets in which copper/titanium wires are formed into 'nail-like' objects by a process of melting and micromachining, so that energy can be reliably coupled to a 24 {micro}m diameter wire. An extreme-ultraviolet image of the interaction of the Titan laser with such a target is shown.
Date: December 18, 2007
Creator: Pasley, J; Wei, M; Shipton, E; Chen, S; Ma, T; Beg, F N et al.
Partner: UNT Libraries Government Documents Department

Snowmass 2001: Jet energy flow project

Description: Conventional cone jet algorithms arose from heuristic considerations of LO hard scattering coupled to independent showering. These algorithms implicitly assume that the final states of individual events can be mapped onto a unique set of jets that are in turn associated with a unique set of underlying hard scattering partons. Thus each final state hadron is assigned to a unique underlying parton. The Jet Energy Flow (JEF) analysis described here does not make such assumptions. The final states of individual events are instead described in terms of flow distributions of hadronic energy. Quantities of physical interest are constructed from the energy flow distribution summed over all events. The resulting analysis is less sensitive to higher order perturbative corrections and the impact of showering and hadronization than the standard cone algorithms.
Date: December 5, 2002
Creator: al., C. F. Berger et
Partner: UNT Libraries Government Documents Department

Completion of Hanford Tanks Initiative characterization milestone T04-98-523

Description: The HTI subsurface characterization task will use the Hanford Cone Penetrometer platform (CPP) to deploy soil sensor and sampling probes into the vadose zone/soils around AX-104 during FY-99. This document provides copies of the first data collected from the HTI sensor probes during vendor field developmental tests performed at a Cold test site in the Hanford 200 East area. Conduct of the initial test also established completion of a major contractor milestone of the HTI Characterization task (MS T04-98-523: Complete preparation of the HTICP probes and transfer to Hanford/HTI. Conduct an initial MSP push using the CPP).
Date: October 23, 1998
Creator: IWATATE, D.F.
Partner: UNT Libraries Government Documents Department


Description: The HTI subsurface characterization task will use the Hanford Cone Penetrometer platform (CPP) to deploy soil sensor and sampling probes into the vadose zone/soils around AX-104 during FY-99. This report provides the data and information compiled during vendor field development tests and laboratory/bench checkout. This document is a vendor deliverable item identified in the ARA Statement of Work HNF-2881, Revision 1. This version of the DTR includes to-be-determined items and some incomplete sections. The Rev. 0 is being released to support the concurrent task of procedure preparation and Qualification Test Plan preparation. Revision 1 is planned to contain all data and information.
Date: October 26, 1998
Creator: Iwatate, D. F.
Partner: UNT Libraries Government Documents Department

Liguefaction Evaluations at the Savannah River Site a Case History

Description: Over the past decade, liquefaction assessments have been performed for many existing and planned critical facilities at the Department of Energy's Savannah River Site (SRS). The assessments incorporated site-specific Cyclic Resistance Ratio (CRR) and K with the use of the cone penetration test (CPT). The SRS-specific CRR and K were developed from laboratory testing of carefully collected samples. Test results show SRS soils have increased liquefaction resistance of two to three times when compared to standard literature for Holocene-age deposits. This increase in strength can be attributed to many factors such as aging and overconsolidation. The purpose of this paper is to discuss liquefaction methodologies used at the SRS. Specifically, (1) use of the CPT and correlations of CPT-derived results with that of high-quality undisturbed samples; (2) aging; and (3) K vertical confining stress factor.
Date: September 23, 2003
Creator: McHood, M.D.
Partner: UNT Libraries Government Documents Department

Turbulent Boundary Layer on a Yawed Cone in a Supersonic Stream

Description: "The momentum integral equations are derived for the boundary layer on an arbitrary curved surface, using a streamline coordinate system. Computations of the turbulent boundary layer on a slightly yawed cone are made for a Prandtl number 0.70, wall to free-stream temperature ratios of 1/2, 1, and 2, and Mach numbers from 1 to 4. Deflection of the fluid in the boundary layer from outer stream direction, local friction coefficient, displacement surface, lift coefficient, and pitching-moment coefficient are presented" (p. 1).
Date: January 1958
Creator: Braun, Willis H.
Partner: UNT Libraries Government Documents Department

Automating Shallow Seismic Imaging

Description: This seven-year, shallow-seismic reflection research project had the aim of improving geophysical imaging of possible contaminant flow paths. Thousands of chemically contaminated sites exist in the United States, including at least 3,700 at Department of Energy (DOE) facilities. Imaging technologies such as shallow seismic reflection (SSR) and ground-penetrating radar (GPR) sometimes are capable of identifying geologic conditions that might indicate preferential contaminant-flow paths. Historically, SSR has been used very little at depths shallower than 30 m, and even more rarely at depths of 10 m or less. Conversely, GPR is rarely useful at depths greater than 10 m, especially in areas where clay or other electrically conductive materials are present near the surface. Efforts to image the cone of depression around a pumping well using seismic methods were only partially successful (for complete references of all research results, see the full Final Technical Report, DOE/ER/14826-F), but peripheral results included development of SSR methods for depths shallower than one meter, a depth range that had not been achieved before. Imaging at such shallow depths, however, requires geophone intervals of the order of 10 cm or less, which makes such surveys very expensive in terms of human time and effort. We also showed that SSR and GPR could be used in a complementary fashion to image the same volume of earth at very shallow depths. The primary research focus of the second three-year period of funding was to develop and demonstrate an automated method of conducting two-dimensional (2D) shallow-seismic surveys with the goal of saving time, effort, and money. Tests involving the second generation of the hydraulic geophone-planting device dubbed the ''Autojuggie'' showed that large numbers of geophones can be placed quickly and automatically and can acquire high-quality data, although not under rough topographic conditions. In some easy-access environments, this device could ...
Date: December 9, 2004
Creator: Steeples, Don W.
Partner: UNT Libraries Government Documents Department

A Cone Jet-Finding Algorithm for Heavy-Ion Collisions at LHCEnergies

Description: Standard jet finding techniques used in elementary particle collisions have not been successful in the high track density of heavy-ion collisions. This paper describes a modified cone-type jet finding algorithm developed for the complex environment of heavy-ion collisions. The primary modification to the algorithm is the evaluation and subtraction of the large background energy, arising from uncorrelated soft hadrons, in each collision. A detailed analysis of the background energy and its event-by-event fluctuations has been performed on simulated data, and a method developed to estimate the background energy inside the jet cone from the measured energy outside the cone on an event-by-event basis. The algorithm has been tested using Monte-Carlo simulations of Pb+Pb collisions at {radical}s = 5.5 TeV for the ALICE detector at the LHC. The algorithm can reconstruct jets with a transverse energy of 50 GeV and above with an energy resolution of {approx} 30%.
Date: July 27, 2006
Creator: Blyth, S.-L.; Horner, M.J.; Awes, T.C.; Cormier, T.; Gray, H.M.; Klay, J.L. et al.
Partner: UNT Libraries Government Documents Department

Fast Electron Generation in Cones with Ultra-Intense Laser Pulses

Description: Experimental results from copper cones irradiated with ultra-intense laser light are presented. Spatial images and total yields of Cu K{sub {alpha}} fluorescence were measured as a function of the laser focusing properties. The fluorescence emission extends into the cone approximately 300 {micro}m from the cone tip and cannot be explained by ray tracing including cone wall absorption. In addition the total fluorescence yield from cones is an order of magnitude higher than for equivalent mass foil targets. Indications are that the physics of the laser cone interaction is dominated by preplasma created from the long duration, low energy pre-pulse from the laser.
Date: December 7, 2007
Creator: Mackinnon, A; VanWoerkom, L; Akli, K; Bartal, T; Beg, F; Chawla, S et al.
Partner: UNT Libraries Government Documents Department

National Ignition Campaign (NIC) Precision Tuning Series Shock Timing Experiments

Description: A series of precision shock timing experiments have been performed on NIF. These experiments continue to adjust the laser pulse shape and employ the adjusted cone fraction (CF) in the picket (1st 2 ns of the laser pulse) as determined from the re-emit experiment series. The NIF ignition laser pulse is precisely shaped and consists of a series of four impulses, which drive a corresponding series of shock waves of increasing strength to accelerate and compress the capsule ablator and fuel layer. To optimize the implosion, they tune not only the strength (or power) but also, to sub-nanosecond accuracy, the timing of the shock waves. In a well-tuned implosion, the shock waves work together to compress and heat the fuel. For the shock timing experiments, a re-entrant cone is inserted through both the hohlraum wall and the capsule ablator allowing a direct optical view of the propagating shocks in the capsule interior using the VISAR (Velocity Interferometer System for Any Reflector) diagnostic from outside the hohlraum. To emulate the DT ice of an ignition capsule, the inside of the cone and the capsule are filled with liquid deuterium.
Date: July 19, 2011
Creator: Robey, H F & Celliers, P M
Partner: UNT Libraries Government Documents Department

Integrated Status and Effectiveness Monitoring Program Population Estimates for Juvenile Salmonids in Nason Creek, WA ; 2008 Annual Report.

Description: This report summarizes juvenile coho, spring Chinook, and steelhead salmon migration data collected at a 1.5m diameter cone rotary fish trap on Nason Creek during 2008; providing abundance and freshwater productivity estimates. We used species enumeration at the trap and efficiency trials to describe emigration timing and to estimate the number of emigrants. Trapping began on March 2, 2008 and was suspended on December 11, 2008 when snow and ice accumulation prevented operation. During 2008, 0 brood year (BY) 2006 coho, 1 BY2007 coho, 906 BY2006 spring Chinook, 323 BY2007 fry Chinook, 2,077 BY2007 subyearling Chinook, 169 steelhead smolts, 414 steelhead fry and 2,390 steelhead parr were trapped. Mark-recapture trap efficiency trials were performed over a range of stream discharge stages. A total of 2,639 spring Chinook, 2,154 steelhead and 12 bull trout were implanted with Passive Integrated Transponder (PIT) tags. Most PIT tagged fish were used for trap efficiency trials. We were unable to identify a statistically significant relationship between stream discharge and trap efficiency, thus, pooled efficiency estimates specific to species and trap size/position were used to estimate the number of fish emigrating past the trap. We estimate that 5,259 ({+-} 359; 95% CI) BY2006 Chinook, 16,816 ({+-} 731; 95% CI) BY2007 Chinook, and 47,868 ({+-} 3,780; 95% CI) steelhead parr and smolts emigrated from Nason Creek in 2008.
Date: July 20, 2009
Creator: Collins, Matthew & Murdoch, Keely
Partner: UNT Libraries Government Documents Department

In-vivo imaging of the photoreceptor mosaic in retinal dystrophies and correlations with visual function

Description: To relate in-vivo microscopic retinal changes to visual function assessed with clinical tests in patients with various forms of retinal dystrophies. The UC Davis Adaptive Optics (AO) Fundus Camera was used to acquire in-vivo retinal images at the cellular level. Visual function tests, consisting of visual field analysis, multifocal electroretinography (mfERG), contrast sensitivity and color vision measures, were performed on all subjects. Five patients with different forms of retinal dystrophies and three control subjects were recruited. Cone densities were quantified for all retinal images. In all images of diseased retinas, there were extensive areas of dark space between groups of photoreceptors, where no cone photoreceptors were evident. These irregular features were not seen in healthy retinas, but were characteristic features in fundi with retinal dystrophies. There was a correlation between functional vision loss and the extent to which the irregularities occurred in retinal images. Cone densities were found to decrease with an associated decrease in retinal function. AO fundus photography is a reliable technique for assessing and quantifying the changes in the photoreceptor layer as disease progresses. Furthermore, this technique can be useful in cases where visual function tests give borderline or ambiguous results, as it allows visualization of individual photoreceptors.
Date: October 26, 2005
Creator: Choi, S; Doble, N; Hardy, J; Jones, S; Keltner, J; Olivier, S et al.
Partner: UNT Libraries Government Documents Department