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1

The GRAVITY instrument software/high-level software  

NASA Astrophysics Data System (ADS)

GRAVITY is the four-beam, near-infrared, AO-assisted, fringe tracking, astrometric and imaging instrument for the Very Large Telescope Interferometer (VLTI). It is requiring the development of one of the most complex instrument software systems ever built for an ESO instrument. Apart from its many interfaces and interdependencies, one of the most challenging aspects is the overall performance and stability of this complex system. The three infrared detectors and the fast reflective memory network (RMN) recorder contribute a total data rate of up to 20 MiB/s accumulating to a maximum of 250 GiB of data per night. The detectors, the two instrument Local Control Units (LCUs) as well as the five LCUs running applications under TAC (Tools for Advanced Control) architecture, are interconnected with fast Ethernet, RMN fibers and dedicated fiber connections as well as signals for the time synchronization. Here we give a simplified overview of all subsystems of GRAVITY and their interfaces and discuss two examples of high-level applications during observations: the acquisition procedure and the gathering and merging of data to the final FITS file.

Burtscher, Leonard; Wieprecht, Ekkehard; Ott, Thomas; Kok, Yitping; Yazici, Senol; Anugu, Narsireddy; Dembet, Roderick; Fedou, Pierre; Lacour, Sylvestre; Ott, Jürgen; Paumard, Thibaut; Lapeyrere, Vincent; Kervella, Pierre; Abuter, Roberto; Pozna, Eszter; Eisenhauer, Frank; Blind, Nicolas; Genzel, Reinhard; Gillessen, Stefan; Hans, Oliver; Haug, Marcus; Haussmann, Frank; Kellner, Stefan; Lippa, Magdalena; Pfuhl, Oliver; Sturm, Eckhard; Weber, Johannes; Amorim, Antonio; Brandner, Wolfgang; Rousselet-Perraut, Karine; Perrin, Guy S.; Straubmeier, Christian; Schöller, Markus

2014-07-01

2

Highly subcooled pool boiling heat transfer at various gravity levels Jungho Kim a,*, John F. Benton b  

E-print Network

An understanding of boiling and critical heat flux in microgravity environments is important to the design whether or not gravity af- fected the boiling process. The results of these early experiments were somewhat contradictory, with some experiments showing no effect of gravity on heat transfer and others

Kim, Jungho

3

High-gravity central stars  

E-print Network

NLTE spectral analyses of high-gravity central stars by means of state-of-the-art model atmosphere techniques provide information about the precursor AGB stars. The hydrogen-deficient post-AGB stars allow investigations on the intershell matter which is apparently exhibited at the stellar surface. We summarize recent results from imaging, spectroscopy, and spectropolarimetry.

Thomas Rauch

2006-07-11

4

Tether implications on Space Station gravity level  

NASA Technical Reports Server (NTRS)

The use of a tether on the Space Station is discussed. The effefcts of the tether on the microgravity environment on the Space station are described. A tethered variable gravity laboratory for investigating low gravity processes using gravity magnitude and time as variables is considered.

Kroll, K. R.

1986-01-01

5

The Constant Levelers: Water, Ice, and Gravity  

NSDL National Science Digital Library

This site has information about the work of three of the agents of erosion in the Northern Cascade Range. Since much of the range is made up of exotic terrains that probably did not evolve on the same spot on the Earth as the present North Cascades, the geologists confine their view to some time since the earliest Tertiary. Within that time frame, they can speculatively recreate the North Cascade scene and ponder its erosional history. The erosional work of rivers has constantly been altered by volcanic activity and whatever drainage pattern was established. It was profoundly altered about 35 million years ago by the renewed volcanic activity of the Cascade Volcanic Arc. A section about how rivers erode describes differential erosion, stream capture, and base level. The section about glaciers explains how they are formed, how they do their work, and what is left behind. The section about the work of gravity focuses on creep and landslides.

6

High-Resolution Gravity and Time-Varying Gravity Field Recovery using GRACE and CHAMP  

NASA Technical Reports Server (NTRS)

This progress report summarizes the research work conducted under NASA's Solid Earth and Natural Hazards Program 1998 (SENH98) entitled High Resolution Gravity and Time Varying Gravity Field Recovery Using GRACE (Gravity Recovery and Climate Experiment) and CHAMP (Challenging Mini-satellite Package for Geophysical Research and Applications), which included a no-cost extension time period. The investigation has conducted pilot studies to use the simulated GRACE and CHAMP data and other in situ and space geodetic observable, satellite altimeter data, and ocean mass variation data to study the dynamic processes of the Earth which affect climate change. Results from this investigation include: (1) a new method to use the energy approach for expressing gravity mission data as in situ measurements with the possibility to enhance the spatial resolution of the gravity signal; (2) the method was tested using CHAMP and validated with the development of a mean gravity field model using CHAMP data, (3) elaborate simulation to quantify errors of tides and atmosphere and to recover hydrological and oceanic signals using GRACE, results show that there are significant aliasing effect and errors being amplified in the GRACE resonant geopotential and it is not trivial to remove these errors, and (4) quantification of oceanic and ice sheet mass changes in a geophysical constraint study to assess their contributions to global sea level change, while the results improved significant over the use of previous studies using only the SLR (Satellite Laser Ranging)-determined zonal gravity change data, the constraint could be further improved with additional information on mantle rheology, PGR (Post-Glacial Rebound) and ice loading history. A list of relevant presentations and publications is attached, along with a summary of the SENH investigation generated in 2000.

Shum, C. K.

2002-01-01

7

The influence of gravity levels on soot formation for the combustion of ethylene-air mixture  

NASA Astrophysics Data System (ADS)

The reduced mechanism coupled with 2D flame code using CHEMKIN II to investigate the effect of gravity on flame structure and soot formation in diffusion flames. The results show that the gravity has a rather significant effect on flame structure and soot formation. The visible flame height and peak soot volume fraction in general increases with the gravity from 1 g decreased to 0 g. The peak flame temperature decreases with decreasing gravity level. Comparing the calculated results from 1 g to 0 g, the flame shape becomes wider, the high temperature zone becomes shorter, the mixture velocity has a sharp decrease, the soot volume fraction has a sharp increase and CO and unprovided species distribution becomes wider along radial direction. At normal and half gravity, the flame is buoyancy controlled and the axial velocity is largely independent of the coflow air velocity. At microgravity (0 g), the flame is momentum controlled.

Zhang, Y.; Liu, D.; Li, S.; Li, Y.; Lou, C.

2014-12-01

8

Gravity Surface Wave Bifurcation in a Highly Turbulent Swirling Flow  

E-print Network

Gravity Surface Wave Bifurcation in a Highly Turbulent Swirling Flow Michael Baumer University Gravity Wave 2 3 Measurements 3 4 Mechanical Hardware: Problems and Solutions 5 5 Results 7 6 Conclusions investigated a free-surface gravity wave bifurcation in the large-separation regime, that is, where

Witten, Thomas A.

9

High level nuclear waste  

SciTech Connect

The DOE Division of Waste Products through a lead office at Savannah River is developing a program to immobilize all US high-level nuclear waste for terminal disposal. DOE high-level wastes include those at the Hanford Plant, the Idaho Chemical Processing Plant, and the Savannah River Plant. Commercial high-level wastes, for which DOE is also developing immobilization technology, include those at the Nuclear Fuel Services Plant and any future commercial fuels reprocessing plants. The first immobilization plant is to be the Defense Waste Processing Facility at Savannah River, scheduled for 1983 project submission to Congress and 1989 operation. Waste forms are still being selected for this plant. Borosilicate glass is currently the reference form, but alternate candidates include concretes, calcines, other glasses, ceramics, and matrix forms.

Crandall, J L

1980-01-01

10

Mars high resolution gravity fields from MRO, Mars seasonal gravity, and other dynamical parameters  

Microsoft Academic Search

With 2 years of tracking data collection from the MRO spacecraft, there is noticeable improvement in the high frequency portion of the spherical harmonic Mars gravity field. The new JPL Mars gravity fields, MRO110B and MRO110B2, show resolution near degree 90. Additional years of MGS and Mars Odyssey tracking data result in improvement for the seasonal J gravity changes which

Alex S. Konopliv; Sami W. Asmar; William M. Folkner; Özgür Karatekin; Daniel C. Nunes; Suzanne E. Smrekar; Charles F. Yoder; Maria T. Zuber

2011-01-01

11

Mars high resolution gravity fields from MRO, Mars seasonal gravity, and other dynamical parameters  

Microsoft Academic Search

With 2years of tracking data collection from the MRO spacecraft, there is noticeable improvement in the high frequency portion of the spherical harmonic Mars gravity field. The new JPL Mars gravity fields, MRO110B and MRO110B2, show resolution near degree 90. Additional years of MGS and Mars Odyssey tracking data result in improvement for the seasonal J¯3 gravity changes which compares

Alex S. Konopliv; Sami W. Asmar; William M. Folkner; Özgür Karatekin; Daniel C. Nunes; Suzanne E. Smrekar; Charles F. Yoder; Maria T. Zuber

2011-01-01

12

A high frequency resonance gravity gradiometer  

SciTech Connect

A new setup OGRAN—the large scale opto-acoustical gravitational detector is described. As distinguished from known gravitational bar detectors it uses the optical interferometrical readout for registering weak variations of gravity gradient at the kilohetz frequency region. At room temperature, its sensitivity is limited only by the bar Brownian noise at the bandwidth close to 100 Hz. It is destined for a search for rare events—gravitational pulses coincident with signals of neutrino scintillator (BUST) in the deep underground of Baksan Neutrino Observatory of INR RAS.

Bagaev, S. N.; Kvashnin, N. L.; Skvortsov, M. N. [Laser Physics Institute SB RAS, Novosibirsc (Russian Federation); Bezrukov, L. B.; Krysanov, V. A. [Institute of Nuclear Physics RAS, Moscow (Russian Federation); Oreshkin, S. I.; Motylev, A. M.; Popov, S. M.; Samoilenko, A. A.; Yudin, I. S. [Lomonosov MSU, Sternberg Astronomical Institute, Moscow (Russian Federation); Rudenko, V. N. [Institute of Nuclear Physics RAS, Moscow (Russian Federation); Lomonosov MSU, Sternberg Astronomical Institute, Moscow (Russian Federation)

2014-06-15

13

GRAVITY  

NSDL National Science Digital Library

3rd Grade Science Standard 4: Students will understand that objects near Earth are pulled toward Earth by gravity Objective 2: Describe the effects of gravity on the motion of an object In this activity we will learn how gravity effects the motion of an object. We will do this by finding out what gravity is and watching experiments on gravity. Finally, we will conduct our own experiment to see first hand how gravity effects everything around us. So, what is gravity? Is it a term that you have heard before? What does it do? Why is it so important? Why do we need to know how it works? If you\\'ve ever wondered what the answers to these questions are, then you\\'re in ...

Ms. Hendricks

2007-11-06

14

Calibration of GOCE SGG data using high–low SST, terrestrial gravity data and global gravity field models  

Microsoft Academic Search

It is the aim of the GOCE mission to determine a model of the Earth’s gravity field with high accuracy and resolution. For this purpose, gravity gradients will be measured in combination with high–low satellite-to-satellite tracking. The gravity gradients are derived from pair-wise differenced accelerations as determined by the six three-axes accelerometers that form the GOCE gradiometer. Since the measured

J. Bouman; R. Koop; C. C. Tscherning; P. Visser

2004-01-01

15

Hydrological Modeling of Groundwater Disturbance to Gravity Signal for High-accuracy Monitoring of Volcanic Activity  

NASA Astrophysics Data System (ADS)

Gravity observation is one of the effective methods to detect magma movements in volcanic eruptions [e.g., Furuya et al., J. Geoph. Res., 2003]. Groundwater-derived disturbances have to be corrected from gravity variations for highly accurate monitoring of volcanic activities. They have been corrected with empirical methods, such as tank models and regression curves [e.g., Imanishi et al., J. Geodyn., 2006]. These methods, however, are not based on hydrological background, and are very likely to eliminate volcanic signals excessively. The correction method of groundwater disturbance has to be developed with hydrological and quantitative approach. We thus estimate the gravity disturbance arising from groundwater as follows. (1) Groundwater distributions are simulated on a hydrological model, utilizing groundwater flow equations. (2) Groundwater-derived gravity value is estimated for each instant of time, by integrating groundwater distributions spatially. (3) The groundwater-derived gravity, as the correction value, is subtracted from observed gravity data. In this study, we simulated groundwater flow and groundwater-derived gravity value on the east part of the Asama volcano, central Japan. A simple hydrological model was supposed, consisting of homogeneous soil, lying on a flat impermeable basement. Hydraulic conductivity, which defines groundwater velocity, was set as 2.0×10-6[m/s], which is consistent with typical volcanic soils. We also observed time variations of watertable height, soil moisture and gravity simultaneously during the summer of 2006 at Asama volcano, and compared the observations with the theoretical values. Both simulated groundwater distributions and gravity changes agree fairly well with observed values. On variations of water level and moisture content, rapid increase at the time of rainfalls and exponential decrease after rainfalls were illustrated. Theoretical gravity changes explained 90% of the observed gravity increase (+20?gals) for the heavy rainfall (200mm) of mid-July 2006. These facts showed that even a simple hydrological model can reproduce characteristic variations of groundwater and gravity at the same time. We believe that hydrological simulation with more sophisticated model (such as 3D inhomogeneous soil lying on a curved basement) will enable us to estimate groundwater disturbance more accurately. Improved groundwater correction will reveal detailed magma movements in volcanic eruptions.

Kazama, T.; Okubo, S.

2007-12-01

16

A Model for High Energy Scattering in Quantum Gravity  

Microsoft Academic Search

We present a model for high energy two body scattering in a quantum theory of gravity. The model is applicable for center of mass energies higher than the relevant Planck scale. At impact parameters smaller than the Schwarzchild radius appropriate to the center of mass energy and total charge of the initial state, the cross section is dominated by an

Tom Banks; Willy Fischler

1999-01-01

17

Sensitivity study of high eccentricity orbits for Mars gravity recovery  

NASA Astrophysics Data System (ADS)

By linear perturbation theory, a sensitivity study is presented to calculate the contribution of the Mars gravity field to the orbital perturbations in velocity for spacecrafts in both low eccentricity Mars orbits and high eccentricity orbits (HEOs). In order to improve the solution of some low degree/order gravity coefficients, a method of choosing an appropriate semimajor axis is often used to calculate an expected orbital resonance, which will significantly amplify the magnitude of the position and velocity perturbations produced by certain gravity coefficients. We can then assess to what degree/order gravity coefficients can be recovered from the tracking data of the spacecraft. However, this existing method can only be applied to a low eccentricity orbit, and is not valid for an HEO. A new approach to choosing an appropriate semimajor axis is proposed here to analyze an orbital resonance. This approach can be applied to both low eccentricity orbits and HEOs. This small adjustment in the semimajor axis can improve the precision of gravity field coefficients and does not affect other scientific objectives.

He, Zhi-Zhou; Huang, Cheng-Li

2015-01-01

18

Visual analysis of flow boiling at different gravity levels in 4.0 mm tube  

NASA Astrophysics Data System (ADS)

The aim of the present paper is to describe the results of flow boiling heat transfer at low gravity and compare them with those obtained at earth gravity, evaluating possible differences. The experimental campaigns at low gravity have been performed during the parabolic flight campaign of October-November 2013. The paper will show the analysis of differences between the heat transfer coefficients and vapour bubble parameters at normal and at zero gravity. The results of 4.0 mm tube are presented and discussed. With respect to terrestrial gravity, heat transfer is systematically lower at microgravity in the range of the experimental conditions. Heat transfer differences for the two gravity conditions are related to the different bubble size in each of them. The size of a bubble in flow boiling is affected by the gravity level, being larger at low gravity, unless inertial forces are largely predominant over buoyancy and other forces acting on the bubble itself when detaching from a heated wall. Vapour bubble parameters (bubble diameter, bubble length, width, and nose velocity) have been measured.

Valencia-Castillo, C. M.; Celata, G. P.; Saraceno, L.; Zummo, G.

2014-11-01

19

Goce and Its Role in Combined Global High Resolution Gravity Field Determination  

NASA Astrophysics Data System (ADS)

Combined high-resolution gravity field models serve as a mandatory basis to describe static and dynamic processes in system Earth. Ocean dynamics can be modeled referring to a high-accurate geoid as reference surface, solid earth processes are initiated by the gravity field. Also geodetic disciplines such as height system determination depend on high-precise gravity field information. To fulfill the various requirements concerning resolution and accuracy, any kind of gravity field information, that means satellite as well as terrestrial and altimetric gravity field observations have to be included in one combination process. A key role is here reserved for GOCE observations, which contribute with its optimal signal content in the long to medium wavelength part and enable a more accurate gravity field determination than ever before especially in areas, where no high-accurate terrestrial gravity field observations are available, such as South America, Asia or Africa. For our contribution we prepare a combined high-resolution gravity field model up to d/o 720 based on full normal equation including recent GOCE, GRACE and terrestrial / altimetric data. For all data sets, normal equations are set up separately, relative weighted to each other in the combination step and solved. This procedure is computationally challenging and can only be performed using super computers. We put special emphasis on the combination process, for which we modified especially our procedure to include GOCE data optimally in the combination. Furthermore we modified our terrestrial/altimetric data sets, what should result in an improved outcome. With our model, in which we included the newest GOCE TIM4 gradiometry results, we can show how GOCE contributes to a combined gravity field solution especially in areas of poor terrestrial data coverage. The model is validated by independent GPS leveling data in selected regions as well as computation of the mean dynamic topography over the oceans. Further, we analyze the statistical error estimates derived from full covariance propagation and compare them with the absolute validation with independent data sets.

Fecher, T.; Pail, R.; Gruber, T.

2013-12-01

20

Acceleration of high gravity yeast fermentations by acetaldehyde addition  

Microsoft Academic Search

In high gravity Saccharomyces cerevisiae fermentations containing 300 g glucose l-1, daily addition of acetaldehyde to a total of 93 mM shortened the time required to ferment the first 250 g glucose l-1 from 790 h to 585 h. Acetaldehyde feeding had no effect on the ethanol yield but increased by 135%, 78% and 77% the final concentrations of 2,3-butanediol,

Andrew R. Barber; Marcus Henningsson; Neville B. Pamment

2002-01-01

21

Investigating High Field Gravity using Astrophysical Techniques  

SciTech Connect

The purpose of these lectures is to introduce particle physicists to astrophysical techniques. These techniques can help us understand certain phenomena important to particle physics that are currently impossible to address using standard particle physics experimental techniques. As the subject matter is vast, compromises are necessary in order to convey the central ideas to the reader. Many general references are included for those who want to learn more. The paragraphs below elaborate on the structure of these lectures. I hope this discussion will clarify my motivation and make the lectures easier to follow. The lectures begin with a brief review of more theoretical ideas. First, elements of general relativity are reviewed, concentrating on those aspects that are needed to understand compact stellar objects (white dwarf stars, neutron stars, and black holes). I then review the equations of state of these objects, concentrating on the simplest standard models from astrophysics. After these mathematical preliminaries, Sec. 2(c) discusses 'The End State of Stars'. Most of this section also uses the simplest standard models. However, as these lectures are for particle physicists, I also discuss some of the more recent approaches to the equation of state of very dense compact objects. These particle-physics-motivated equations of state can dramatically change how we view the formation of black holes. Section 3 focuses on the properties of the objects that we want to characterize and measure. X-ray binary systems and Active Galactic Nuclei (AGN) are stressed because the lectures center on understanding very dense stellar objects, black hole candidates (BHCs), and their accompanying high gravitational fields. The use of x-ray timing and gamma-ray experiments is also introduced in this section. Sections 4 and 5 review information from x-ray and gamma-ray experiments. These sections also discuss the current state of the art in x-ray and gamma-ray satellite experiments and plans for future experiments.

Bloom, Elliott D.; /SLAC

2008-02-01

22

Highly relativistic spin-gravity coupling for fermions  

NASA Astrophysics Data System (ADS)

Descriptions of highly relativistic fermions in a gravitational field in the classical (nonquantum) and quantum approaches are discussed. The results following from the Mathisson-Papapetrou equations for a fast spinning particle in Schwarzschild's and Kerr's background are considered. Numerical estimates for electron, proton and neutrino in the gravitational field of black holes are presented. The general relativistic Dirac equation is analyzed from the point of view it is using for the adequate description of highly relativistic fermions in a gravitational field, in the linear and nonlinear spin approximation. It is necessary to have some corrected Dirac equation for a highly relativistic fermion with strong spin-gravity coupling.

Plyatsko, Roman; Fenyk, Mykola

2015-03-01

23

Highly relativistic spin-gravity coupling for fermions  

E-print Network

Descriptions of highly relativistic fermions in a gravitational field in the classical (nonquantum) and quantum approaches are discussed. The results following from the Mathisson-Papapetrou equations for a fast spinning particle in Schwarzschild's and Kerr's background are considered. Numerical estimates for electron, proton and neutrino in the gravitational field of black holes are presented.The general relativistic Dirac equation is analyzed from the point of view it is using for the adequate description of highly relativistic fermions in a gravitational field, in the linear and nonlinear spin approximation. It is necessary to have some corrected Dirac equation for a highly relativistic fermion with strong spin-gravity coupling.

Roman Plyatsko; Mykola Fenyk

2015-03-29

24

Highly relativistic spin-gravity coupling for fermions  

E-print Network

Descriptions of highly relativistic fermions in a gravitational field in the classical (nonquantum) and quantum approaches are discussed. The results following from the Mathisson-Papapetrou equations for a fast spinning particle in Schwarzschild's and Kerr's background are considered. Numerical estimates for electron, proton and neutrino in the gravitational field of black holes are presented.The general relativistic Dirac equation is analyzed from the point of view it is using for the adequate description of highly relativistic fermions in a gravitational field, in the linear and nonlinear spin approximation. It is necessary to have some corrected Dirac equation for a highly relativistic fermion with strong spin-gravity coupling.

Plyatsko, Roman

2015-01-01

25

High-resolution gravity survey: Investigation of subsurface structures at Poas volcano, Costa Rica  

E-print Network

High-resolution gravity survey: Investigation of subsurface structures at Poa´s volcano, Costa Rica correction. Here we describe a high- resolution gravity survey at Poa´s volcano, Costa Rica. Our gravity structures at Poa´s volcano, Costa Rica, Geophys. Res. Lett., 31, L15602, doi:10.1029/2004GL020563. 1

Williams-Jones, Glyn

26

Wave breaking and critical levels for propagating inertio-gravity waves in the lower stratosphere  

Microsoft Academic Search

This paper analyses and interprets the formation of mixed layers due to propagating inertio-gravity waves observed during the Fronts and Atlantic Storm-Track EXperiment. The data used are high-vertical-resolution soundings launched from different sites located in the North Atlantic sector. In agreement with other studies, attributing the origin of the inertio-gravity waves to the adjustment of the jet stream near fronts,

H. Moldovan; F. Lott; H. Teitelbaum

2002-01-01

27

High-Level Radioactive Waste.  

ERIC Educational Resources Information Center

Presents a method to calculate the amount of high-level radioactive waste by taking into consideration the following factors: the fission process that yields the waste, identification of the waste, the energy required to run a 1-GWe plant for one year, and the uranium mass required to produce that energy. Briefly discusses waste disposal and…

Hayden, Howard C.

1995-01-01

28

The CMS high level trigger  

NASA Astrophysics Data System (ADS)

The CMS experiment has been designed with a 2-level trigger system: the Level 1 Trigger, implemented on custom-designed electronics, and the High Level Trigger (HLT), a streamlined version of the CMS offline reconstruction software running on a computer farm. A software trigger system requires a tradeoff between the complexity of the algorithms running on the available computing power, the sustainable output rate, and the selection efficiency. Here we will present the performance of the main triggers used during the 2012 data taking, ranging from simpler single-object selections to more complex algorithms combining different objects, and applying analysis-level reconstruction and selection. We will discuss the optimisation of the triggers and the specific techniques to cope with the increasing LHC pile-up, reducing its impact on the physics performance.

Gori, Valentina

2014-05-01

29

The CMS High Level Trigger  

NASA Astrophysics Data System (ADS)

The CMS experiment has been designed with a two-level trigger system: the Level-1 Trigger, implemented in custom-designed electronics, and the High-Level Trigger (HLT), a streamlined version of the CMS offline reconstruction software running on a computer farm. A software trigger system requires a tradeoff between the complexity of the algorithms running with the available computing power, the sustainable output rate, and the selection efficiency. We present the performance of the main triggers used during the 2012 data taking, ranging from simple single-object selections to more complex algorithms combining different objects, and applying analysis-level reconstruction and selection. We discuss the optimisation of the trigger and the specific techniques to cope with the increasing LHC pile-up, reducing its impact on the physics performance.

Trocino, Daniele

2014-06-01

30

Quantum Gravity and Extra Dimensions at High-Energy Colliders  

E-print Network

Recently it has been pointed out that the characteristic quantum-gravity scale could be as low as the weak scale in theories with gravity propagating in higher dimensions. The observed smallness of Newton's constant is a consequence of the large compactified volume of the extra dimensions. We investigate the consequences of this supposition for high-energy collider experiments. We do this by first compactifying the higher dimensional theory and constructing a 3+1-dimensional low-energy effective field theory of the graviton Kaluza-Klein excitations and their interactions with ordinary matter. We then consider graviton production processes, and select photon plus missing energy and jet plus missing energy signatures for careful study. We find that both a 1 TeV e+e- collider and the CERN LHC will be able to reliably and perturbatively probe the fundamental gravity scale up to several TeV, with the precise value depending on the number of extra dimensions. Similarly, searches at LEP2 and the Tevatron are able to probe this scale up to approximately 1 TeV. We also discuss virtual graviton exchange, which induces local dimension-eight operators associated with the square of the energy-momentum tensor. We estimate the size of such operators and study their effects on two fermions to two photons observables.

Gian F. Giudice; Riccardo Rattazzi; James D. Wells

2000-03-13

31

High pressure droplet burning experiments in reduced gravity  

NASA Technical Reports Server (NTRS)

A parametric investigation of single droplet gasification regimes is helpful in providing the necessary physical ideas for sub-grid models used in spray combustion numerical prediction codes. A research program has been initiated at the LCSR to explore the vaporization regimes of single and interacting hydrocarbon and liquid oxygen droplets under high pressure conditions. This paper summarizes the status of the LCSR program on the high pressure burning of single fuel droplets; recent results obtained under normal and reduced gravity conditions with suspended droplets are presented. In the work described here, parabolic flights of the CNES Caravelle is used to create a reduced gravity environment of the order of 10(exp -2) g(sub O). For all the droplet burning experiments reported here, the suspended droplet initial diameters are scattered around 1.5 mm; and the ambient air temperature is 300 K. The ambient pressure is varied between 0.1 MPa and 12 MPa. Four fuels are investigated: methanol (Pc = 7.9 MPa), n-heptane (Pc = 2.74 MPa), n-hexane (Pc = 3.01 MPa) and n-octane (Pc = 2.48 MPa).

Chauveau, Christian; Goekalp, Iskender

1995-01-01

32

Degraded EEG response of the human brain in function of gravity levels by the method of chaotic attractor.  

PubMed

The measurement of the influence of different gravity levels on the brain allows to explain how humans react to microgravity in space and to predict the adaptation capability of astronauts. Human electroencephalographic (EEG) signals were recorded during low and high gravity phases of three consecutive days of parabolic flights on the Caravelle aircraft in 1991. EEG signals were processed, using the method of correlation dimensions d of chaotic strange attractors. Results show clear differences between the three flights, with a general decrease over time in the attractor dimensions, a measure of the brain response to changing g levels. However, the dimension is not a one-to-one relation with g levels, as additional variations are observed. Two hypotheses are introduced, the "fatigue/stress" and the "g stress" hypotheses corresponding, respectively, to long-term fatigue accumulated over the three flights, and to short-term fatigue in response to change in g levels. The former explains the overall decrease of dimensions, the latter yields additional variations on shorter time scales. As the brain response degrades with time, at least six degraded modes were observed, explained by both short- and long-term fatigue. PMID:12575723

Pletser, Vladimir; Quadens, Olga

2003-04-01

33

High level white noise generator  

DOEpatents

A wide band, stable, random noise source with a high and well-defined output power spectral density is provided which may be used for accurate calibration of Johnson Noise Power Thermometers (JNPT) and other applications requiring a stable, wide band, well-defined noise power spectral density. The noise source is based on the fact that the open-circuit thermal noise voltage of a feedback resistor, connecting the output to the input of a special inverting amplifier, is available at the amplifier output from an equivalent low output impedance caused by the feedback mechanism. The noise power spectral density level at the noise source output is equivalent to the density of the open-circuit thermal noise or a 100 ohm resistor at a temperature of approximately 64,000 Kelvins. The noise source has an output power spectral density that is flat to within 0.1% (0.0043 db) in the frequency range of from 1 KHz to 100 KHz which brackets typical passbands of the signal-processing channels of JNPT's. Two embodiments, one of higher accuracy that is suitable for use as a standards instrument and another that is particularly adapted for ambient temperature operation, are illustrated in this application.

Borkowski, Casimer J. (Oak Ridge, TN); Blalock, Theron V. (Knoxville, TN)

1979-01-01

34

Optimizing High Level Waste Disposal  

SciTech Connect

If society is ever to reap the potential benefits of nuclear energy, technologists must close the fuel-cycle completely. A closed cycle equates to a continued supply of fuel and safe reactors, but also reliable and comprehensive closure of waste issues. High level waste (HLW) disposal in borosilicate glass (BSG) is based on 1970s era evaluations. This host matrix is very adaptable to sequestering a wide variety of radionuclides found in raffinates from spent fuel reprocessing. However, it is now known that the current system is far from optimal for disposal of the diverse HLW streams, and proven alternatives are available to reduce costs by billions of dollars. The basis for HLW disposal should be reassessed to consider extensive waste form and process technology research and development efforts, which have been conducted by the United States Department of Energy (USDOE), international agencies and the private sector. Matching the waste form to the waste chemistry and using currently available technology could increase the waste content in waste forms to 50% or more and double processing rates. Optimization of the HLW disposal system would accelerate HLW disposition and increase repository capacity. This does not necessarily require developing new waste forms, the emphasis should be on qualifying existing matrices to demonstrate protection equal to or better than the baseline glass performance. Also, this proposed effort does not necessarily require developing new technology concepts. The emphasis is on demonstrating existing technology that is clearly better (reliability, productivity, cost) than current technology, and justifying its use in future facilities or retrofitted facilities. Higher waste processing and disposal efficiency can be realized by performing the engineering analyses and trade-studies necessary to select the most efficient methods for processing the full spectrum of wastes across the nuclear complex. This paper will describe technologies being evaluated at Idaho National Laboratory and the facilities we’ve designed to evaluate options and support optimization.

Dirk Gombert

2005-09-01

35

High gravity fermentation of sugarcane molasses to produce ethanol: Effect of nutrients  

Microsoft Academic Search

Fermentation efficiency of more than 85% was obtained by high gravity fermentation of 33–34°Bx (spec. gravity ?1.134) molasses\\u000a medium with certain nutrients, instead of generally employed medium containing ?16% (w\\/v) total sugar (spec. gravity ?1.090)\\u000a for ethanol fermentation in distilleries to get maximum 80–85% conversion. The fermenting yeast, Saccharomyces, has varied capabilities, depending on the species and nutrition for fermenting

P. Pradeep; O. V. S. Reddy

2010-01-01

36

Extracting high spatial resolution local gravity field from GRACE data  

NASA Astrophysics Data System (ADS)

GRACE spherical harmonic coefficients are typically limited to degree and order 50 or 60. This means that the spatial resolution of geophysical estimates from GRACE gravity field are limited by truncation errors and leakage of signals from, for example, oceans to continents or from one glacier to another. This results in estimates of local mass balance of glaciers or hydrological catchments being inaccurate. In this paper, we use least squares to estimate discrete mass changes of small regions that sum to the integrated signal as seen by GRACE. The goal is to find the highest spatial resolution that can be estimated from GRACE. We find that the spatial resolution is dependent on the latitude of the region, with greater resolution in high latitude regions where the groundtracks are denser. We show results of two regions: estimating mass changes in Australian continent (mid-latitude) to study hydrology of drainage basins, and estimating mass balance in Greenland (high latitude) to study changes of the ice sheet. We find that high negative correlation between neighbouring regions restrict the spatial resolution that can be achieved.

Darbeheshti, N.; Tregoning, P.; McClusky, S.

2012-04-01

37

Very extended E8 and A8 at low levels, gravity and supergravity  

NASA Astrophysics Data System (ADS)

We define a level for a large class of Lorentzian Kac-Moody algebras. Using this we find the representation content of very extended AD-3 and E8 (i.e., E11) at low levels in terms of AD-1 and A10 representations, respectively. The results are consistent with the conjectured very extended A8 and E11 symmetries of gravity and maximal supergravity theories given respectively in preprints hep-th/0104081 and hep-th/0107209. We explain how these results provided further evidence for these conjectures.

West, Peter

2003-06-01

38

Effects of varying gravity levels in parabolic flight on the size-mass illusion.  

PubMed

When an observer lifts two objects with the same weight but different sizes, the smaller object is consistently reported to feel heavier than the larger object even after repeated trials. Here we explored the effect of reduced and increased gravity on this perceptual size-mass illusion. Experiments were performed on board the CNES Airbus A300 Zero-G during parabolic flights eliciting repeated exposures to short periods of zero g, 0.16 g, 0.38 g, one g, and 1.8 g. Subjects were asked to assess perceived heaviness by actively oscillating objects with various sizes and masses. The results showed that a perceptual size-mass illusion was clearly present at all gravity levels. During the oscillations, the peak arm acceleration varied as a function of the gravity level, irrespective of the mass and size of the objects. In other words we did not observe a sensorimotor size-mass illusion. These findings confirm dissociation between the sensorimotor and perceptual systems for determining object mass. In addition, they suggest that astronauts on the Moon or Mars with the eyes closed will be able to accurately determine the relative difference in mass between objects. PMID:24901519

Clément, Gilles

2014-01-01

39

Effects of Varying Gravity Levels in Parabolic Flight on the Size-Mass Illusion  

PubMed Central

When an observer lifts two objects with the same weight but different sizes, the smaller object is consistently reported to feel heavier than the larger object even after repeated trials. Here we explored the effect of reduced and increased gravity on this perceptual size-mass illusion. Experiments were performed on board the CNES Airbus A300 Zero-G during parabolic flights eliciting repeated exposures to short periods of zero g, 0.16 g, 0.38 g, one g, and 1.8 g. Subjects were asked to assess perceived heaviness by actively oscillating objects with various sizes and masses. The results showed that a perceptual size-mass illusion was clearly present at all gravity levels. During the oscillations, the peak arm acceleration varied as a function of the gravity level, irrespective of the mass and size of the objects. In other words we did not observe a sensorimotor size-mass illusion. These findings confirm dissociation between the sensorimotor and perceptual systems for determining object mass. In addition, they suggest that astronauts on the Moon or Mars with the eyes closed will be able to accurately determine the relative difference in mass between objects. PMID:24901519

Clément, Gilles

2014-01-01

40

Tethered gravity laboratories study  

NASA Technical Reports Server (NTRS)

The use is studied of tether systems to improve the lowest possible steady gravity level on the Space Station. Particular emphasis is placed by the microgravity community on the achievement of high quality microgravity conditions. The tether capability is explored for active control of the center of gravity and the analysis of possible tethered configurations.

Lucchetti, F.

1989-01-01

41

Probing Gravity in the High-Redshift Universe with HETDEX  

NASA Astrophysics Data System (ADS)

The addition of dark matter and dark energy to general relativity is degenerate with a modification of the dependence of curvature on the stress-energy tensor in the absence of exotic sources of matter and energy; it is thus valuable to explore the latter as a potential improvement over the former. Though it is inherently difficult to distinguish existing evidence for the general relativity paradigm from that of its more promising alternatives, such theories are associated with different histories for the largely unexplored growth of structure. Zhang, et al. (2007) have enabled discrimination of these possibilities via a new observable parameter EG and have predicted the efficacy of several future astronomical surveys to determine its value. In this work, we examine the ability of the Hobby Eberly Telescope Dark Energy Experiment (HETDEX) to contribute to calculations of this indicator of gravity at the highest redshifts (1.9 < z < 3.5). We show that a prerequisite of such a measurement is a deeper understanding of the nature of Lyman-? emitting galaxies (LAEs). If HETDEX can constrain the statistical properties of the typical LAE velocity dispersion, then it will not be necessary to wait for the (as yet unplanned) next generation of high-resolution spectrographs to obtain a test of general relativity in the high-redshift universe.

Malz, A. I.; Shandera, S.

2014-01-01

42

High temperature liquid level sensor  

DOEpatents

A length of metal sheathed metal oxide cable is perforated to permit liquid access to the insulation about a pair of conductors spaced close to one another. Changes in resistance across the conductors will be a function of liquid level, since the wetted insulation will have greater electrical conductivity than that of the dry insulation above the liquid elevation.

Tokarz, Richard D. (West Richland, WA)

1983-01-01

43

Arctic margin gravity highs: Deeper meaning for sediment depocenters?  

Microsoft Academic Search

Morphologic, gravity, and seismic reflection\\/refraction data from ca. 10,000 km of Arctic passive continental margins suggest that the numerous oval free-air gravity anomalies, their +50–150 mGal extrema typically located just landward of shelf breaks, are caused by combinations of rapidly deposited Plio-Pleistocene glacial marine sediment loads, older post-breakup sediments, and perhaps causally related density anomalies (mascons) in the underlying oceanic crust. Dispersed

Peter R. Vogt; Woo-Yeol Jung; John Brozena

1998-01-01

44

High Temperature, High Pressure Water Level Sensor  

Microsoft Academic Search

A sensor was developed to measure water level over a range of 750 mm with an uncertainty of +- 20 mm at a temperature from 20 to 250°C and pressure up to 15.2 MPa. The sensor is type 304, flattened stainless steel rod. Its cross section is 1.6 x 3.2 mm, and its measured torsional transit time is a function

G. N. Miller; R. L. Anderson; S. C. Rogers; L. C. Lynnworth; W. B. Studley; W. R. Wade

1980-01-01

45

Superrotation induced by critical-level absorption of gravity waves on Venus - An assessment  

NASA Technical Reports Server (NTRS)

Critical-level absorption of a continuous spectrum of vertically propagating gravity waves is proposed as the mechanism for supporting the superrotation in the deep Venus atmosphere (below the cloud deck). It is shown that the observed westerly zonal wind effectively separates regions where waves of opposite phase speeds are absorbed, leading to westerly mean-flow acceleration below the clouds and easterly above. Using the diagnostic results of Hou and Goody (1985), a quantitative assessment of the required wave spectrum and fluxes of energy and momentum is obtained, and it is shown that they are compatible with observational constraints.

Hou, Arthur Y.; Farrell, Brian F.

1987-01-01

46

High-Level Data Races  

NASA Technical Reports Server (NTRS)

Data races are a common problem in concurrent and multi-threaded programming. They are hard to detect without proper tool support. Despite the successful application of these tools, experience shows that the notion of data race is not powerful enough to capture certain types of inconsistencies occurring in practice. In this paper we investigate data races on a higher abstraction layer. This enables us to detect inconsistent uses of shared variables, even if no classical race condition occurs. For example, a data structure representing a coordinate pair may have to be treated atomically. By lifting the meaning of a data race to a higher level, such problems can now be covered. The paper defines the concepts view and view consistency to give a notation for this novel kind of property. It describes what kinds of errors can be detected with this new definition, and where its limitations are. It also gives a formal guideline for using data structures in a multi-threading environment.

Artho, Cyrille; Havelund, Klaus; Biere, Armin; Koga, Dennis (Technical Monitor)

2003-01-01

47

Silicone oil with high specific gravity for intraocular use  

Microsoft Academic Search

Silicone oil with a higher specific gravity than that of intraocular fluid or polydimethylsiloxane may have special indications in vitreoretinal surgery. Trifluorsiloxane is such a substance, and therefore its biological compatibility was investigated in rabbit eyes. It was found that this substance was clinically well tolerated within the observation time of up to 6 months, even if there was some

V P Gabel; A Kampik; C Gabel; D Spiegel

1987-01-01

48

High-frequency radar observations of atmospheric gravity waves in the high-latitude ionosphere  

SciTech Connect

The Johns Hopkins University high-frequency coherent scatter radar at Goose Bay, Labrador, often observes the effects of propagating atmospheric gravity waves, particularly in ground backscatter returns. To date, these waves have been identified in late fall and early winter on propagation paths directed over the Davis Strait, between northeastern Canada and Greenland. The waves appear as spatially localized enhancements in the backscattered powers, Doppler velocities, and reflection heights. They are generally observed during daylight hours and are usually accompanied by backscatter from higher-latitude ionospheric irregularities that appear to be located near the ionospheric convections reversal boundary. The lowest frequencies associated with the gravity waves lie in the range 0.4 to 0.6 mHz, and the wavelengths lie in the range 300 to 600 km. The waves generally propagate equatorward at an angle of 150{degree} to 180{degree} east of geographic north. During intervals with an expanded polar cap, northward propagating gravity waves are sometimes observed. Measurements of the parameters of the waves and the ranges to the sources suggest that the waves are excited at a height of 100 to 150 km near the convection reversal boundary and the polar cusp, and that the bulk of the observed perturbations are due to Earth-reflected waves.

Samson, J.C. (Univ. of Alberta, Edmonton (Canada)); Greenwald, R.A.; Ruohoniemi, J.M.; Baker, K.B. (Johns Hopkins Univ., Laurel, MD (USA))

1989-08-01

49

High Contamination Levels Lead to Environmental Concerns  

E-print Network

High Contamination Levels Lead to Environmental Concerns High nutrient and bacterial levels Service partnered with the Texas State Soil and Water Conservation Board in 2005 to inform and educate&M AgriLife Extension Service ph. 979.845.1861 e-mail: d-mccorkle@tamu.edu agrilifeextension

50

Tutorial on high-level synthesis  

Microsoft Academic Search

High-level synthesis takes an abstract behavioral specification of a digital system and finds a register-transfer level structure that realizes the given behavior. In this tutorial we will examine the high-level synthesis task, showing how it can be decomposed into a number of distinct but not independent subtasks. Then we will present the techniques that have been developed for solving those

Michael C. McFarland; Alice C. Parker; Raul Carnposano

1988-01-01

51

Centrifugal Sieve for Gravity-Level-Independent Size Segregation of Granular Materials  

NASA Technical Reports Server (NTRS)

Conventional size segregation or screening in batch mode, using stacked vibrated screens, is often a time-consuming process. Utilization of centrifugal force instead of gravity as the primary body force can significantly shorten the time to segregate feedstock into a set of different-sized fractions. Likewise, under reduced gravity or microgravity, a centrifugal sieve system would function as well as it does terrestrially. When vibratory and mechanical blade sieving screens designed for terrestrial conditions were tested under lunar gravity conditions, they did not function well. The centrifugal sieving design of this technology overcomes the issues that prevented sieves designed for terrestrial conditions from functioning under reduced gravity. These sieves feature a rotating outer (cylindrical or conical) screen wall, rotating fast enough for the centrifugal forces near the wall to hold granular material against the rotating screen. Conventional centrifugal sieves have a stationary screen and rapidly rotating blades that shear the granular solid near the stationary screen, and effect the sieving process assisted by the airflow inside the unit. The centrifugal sieves of this new design may (or may not) have an inner blade or blades, moving relative to the rotating wall screen. Some continuous flow embodiments would have no inner auger or blades, but achieve axial motion through vibration. In all cases, the shearing action is gentler than conventional centrifugal sieves, which have very high velocity differences between the stationary outer screen and the rapidly rotating blades. The new design does not depend on airflow in the sieving unit, so it will function just as well in vacuum as in air. One advantage of the innovation for batch sieving is that a batch-mode centrifugal sieve may accomplish the same sieving operation in much less time than a conventional stacked set of vibrated screens (which utilize gravity as the primary driving force for size separation). In continuous mode, the centrifugal sieves can provide steady streams of fine and coarse material separated from a mixed feedstock flow stream. The centrifugal sieves can be scaled to any desired size and/or mass flow rate. Thus, they could be made in sizes suitable for small robotic exploratory missions, or for semi-permanent processing of regolith for extraction of volatiles of minerals. An advantage of the continuous-mode system is that it can be made with absolutely no gravity flow components for feeding material into, or for extracting the separated size streams from, the centrifugal sieve. Thus, the system is capable of functioning in a true microgravity environment. Another advantage of the continuous-mode system is that some embodiments of the innovation have no internal blades or vanes, and thus, can be designed to handle a very wide range of feedstock sizes, including occasional very large oversized pieces, without jamming or seizing up.

Walton, Otis R.; Dreyer, Christopher; Riedel, Edward

2013-01-01

52

Effect of Gravity Level on the Particle Shape and Size During Zeolite Crystal Growth  

NASA Technical Reports Server (NTRS)

A microscopic diffusion model is developed to represent solute transport in the boundary layer of a growing zeolite crystal. This model is used to describe the effect of gravity on particle shape and solute distribution. Particle dynamics and crystal growth kinetics serve as the boundary conditions of flow and convection-diffusion equations. A statistical rate theory is used to obtain the rate of solute transport across the growing interface, which is expressed in terms of concentration and velocity of solute species. Microgravity can significantly decrease the solute velocity across the growing interface compared to its earth-based counterpart. The extent of this reduction highly depends on solute diffusion constant in solution. Under gravity, the flow towards the crystal enhances solute transport rate across the growing interface while the flow away from crystals reduces this rate, suggesting a non-uniform growth rate and thus an elliptic final shape. However, microgravity can significantly reduce the influence of flow and obtain a final product with perfect spherical shape. The model predictions compare favorably with the data of space experiment of zeolites grown in space.

Song, Hong-Wei; Ilebusi, Olusegun J.; Sacco, Albert, Jr.

2003-01-01

53

Parallel Processing at the High School Level.  

ERIC Educational Resources Information Center

This study investigated the ability of high school students to cognitively understand and implement parallel processing. Data indicates that most parallel processing is being taught at the university level. Instructional modules on C, Linux, and the parallel processing language, P4, were designed to show that high school students are highly

Sheary, Kathryn Anne

54

Monitoring Earthquake Fault Slip from Space: Model Implications for a High Precision, High Resolution Dedicated Gravity Mission (Invited)  

NASA Astrophysics Data System (ADS)

Monitoring deformation produced by slip on earthquake faults can be carried out via GPS or InSAR measurements. Both of these types of observations have their advantages and disadvantages, in terms of cost, availability, and technical difficulty. It has been suggested that another method to accomplish many of the same objectives would be via a dedicated gravity mission. The GRACE mission has shown that it is possible to make detailed gravity measurements from space for climate dynamics and other purposes. An important question is what level of accuracy will be needed for precise estimation of fault slip in earthquakes of interest to researchers. To answer this question, we turn to numerical simulations of earthquake fault systems and use these to estimate gravity changes. Rundle (1978) considered the question of gravity changes from dilation sources and thrust faults, and found that gravity changes in these cases were free air anomaly (dilation) and Bouguer anomaly (thrust fault). Walsh and Rice (1978) computed these by a different method and found the same result. Okada (1991) listed gravity and potential Green functions for all possible sources for the general case. Hayes et al (2006) then took the Okada Greens functions and applied them computed from an earlier version of Virtual California earthquake fault system simulations. Those simulations only involved vertical strike slip faults. The current far more advanced generation of Virtual California simulations involves faults of any orientation, dip, and rake. In this talk, we discuss these computations and the implications they have for accuracies needed for a dedicated gravity monitoring mission. Preliminary results are in agreement with previous results from Hayes et al (2006). Computed gravity changes are in the range of tens to hundreds of microgals over distances of few to many tens of kilometers. These values are presumably well within the range of measurement for a modern gravity mission flown either at low altitudes, or via UAVs.

Rundle, J. B.; Sachs, M. K.; Tiampo, K. F.; Fernandez, J.; Turcotte, D. L.; Donnellan, A.; Heien, E. M.; Kellogg, L. H.

2013-12-01

55

Virtuous trees at five- and six-point levels for Yang-Mills theory and gravity  

SciTech Connect

We present a particularly nice D-dimensional graph-based representation of the full color-dressed five-point tree-level gluon amplitude. It possesses the following virtues: (1) it satisfies the color-kinematic correspondence, and thus trivially generates the associated five-point graviton amplitude, (2) all external-state information is encoded in color-ordered partial amplitudes, and (3) one function determines the kinematic contribution of all graphs in the Yang-Mills amplitude, so the associated gravity amplitude is manifestly permutation symmetric. The third virtue, while shared among all known loop-level correspondence-satisfying representations, is novel for tree-level representations sharing the first two virtues. This new D-dimensional representation makes contact with the recently found multiloop five-point representations, suggesting all-loop, all-multiplicity ramifications through unitarity. Additionally we present a slightly less virtuous representation of the six-point maximally helicity-violating (MHV) and MHV amplitudes that holds only in four dimensions.

Broedel, Johannes; Carrasco, John Joseph M. [Stanford Institute for Theoretical Physics and Department of Physics, Stanford University, Stanford, California 94305-4060 (United States); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106 (United States)

2011-10-15

56

High Degree and Order Gravity Fields of the Moon Derived from GRAIL Data  

NASA Astrophysics Data System (ADS)

The Gravity Recovery and Interior Laboratory (GRAIL) spacecraft conducted the mapping of the gravity field of the Moon from March 1, 2012 to May 29, 2012. The twin spacecraft acquired highly precise K Band range-rate (KBRR) intersatellite ranging data and Deep Space Network (DSN) data during this prime mission phase from altitudes of 15 to 75 km above the lunar surface over three lunar months. We have processed these data using the NASA GSFC GEODYN orbit determination and geodetic parameter estimation program, and we have determined gravity fields up to degree and order 420 in spherical harmonics. The new gravity solutions show improved correlations with LOLA-derived topography to high degree and order and resolve many lunar features in the geopotential with a resolution of less than 30 km, including for example the central peak of the crater Tycho. We discuss the methodology used for the processing of the GRAIL data, the quality of the orbit determination on the GRAIL satellites and the derivation of the solutions, and their evaluation with independent data, including Lunar Prospector. We show that with these new GRAIL gravity solutions, we can now fit the low altitude, extended mission Lunar Prospector tracking data better than with any previous gravity model that included the LP data.

Lemoine, F. G.; Goossens, S. J.; Sabaka, T. J.; Nicholas, J. B.; Mazarico, E.; Loomis, B. D.; Chinn, D. S.; Caprette, D.; McCarthy, J. J.; Neumann, G. A.; Zuber, M. T.; Smith, D. E.

2012-12-01

57

High energy behavior of gravity at large N  

NASA Astrophysics Data System (ADS)

A first step in the analysis of the renormalizability of gravity at large N is carried out. Suitable resummations of planar diagrams give rise to a theory in which there is only a finite number of primitive, superficially divergent, Feynman diagrams. The mechanism is similar to the one which makes the 3D Gross-Neveu model renormalizable at large N. The connections with gravitational confinement and Kawai-Lewellen-Tye relations are briefly analyzed. Some potential problems in fulfilling the Zinn-Justin equations are pointed out.

Canfora, F.

2006-09-01

58

High-degree Gravity Models from GRAIL Primary Mission Data  

NASA Technical Reports Server (NTRS)

We have analyzed Ka?band range rate (KBRR) and Deep Space Network (DSN) data from the Gravity Recovery and Interior Laboratory (GRAIL) primary mission (1 March to 29 May 2012) to derive gravity models of the Moon to degree 420, 540, and 660 in spherical harmonics. For these models, GRGM420A, GRGM540A, and GRGM660PRIM, a Kaula constraint was applied only beyond degree 330. Variance?component estimation (VCE) was used to adjust the a priori weights and obtain a calibrated error covariance. The global root?mean?square error in the gravity anomalies computed from the error covariance to 320×320 is 0.77 mGal, compared to 29.0 mGal with the pre?GRAIL model derived with the SELENE mission data, SGM150J, only to 140×140. The global correlations with the Lunar Orbiter Laser Altimeter?derived topography are larger than 0.985 between l = 120 and 330. The free?air gravity anomalies, especially over the lunar farside, display a dramatic increase in detail compared to the pre?GRAIL models (SGM150J and LP150Q) and, through degree 320, are free of the orbit?track?related artifacts present in the earlier models. For GRAIL, we obtain an a posteriori fit to the S?band DSN data of 0.13 mm/s. The a posteriori fits to the KBRR data range from 0.08 to 1.5 micrometers/s for GRGM420A and from 0.03 to 0.06 micrometers/s for GRGM660PRIM. Using the GRAIL data, we obtain solutions for the degree 2 Love numbers, k20=0.024615+/-0.0000914, k21=0.023915+/-0.0000132, and k22=0.024852+/-0.0000167, and a preliminary solution for the k30 Love number of k30=0.00734+/-0.0015, where the Love number error sigmas are those obtained with VCE.

Lemoine, Frank G.; Goossens, Sander J.; Sabaka, Terence J.; Nicholas, Joseph B.; Mazarico, Erwan; Rowlands, David D.; Loomis, Bryant D.; Chinn, Douglas S.; Caprette, Douglas S.; Neumann, Gregory A.; Smith, David E.; Zuber, Maria T.

2013-01-01

59

Retargetable high-level alias analysis  

Microsoft Academic Search

All optimizing compilers must deal with the problem of aliases arising due to the presence of multiple names that reference the same memory areas. Presented in this paper is a staged, high-level alias analysis methodology that provides detailed alias information to a global optimizer implemented at any level in the compilation process. The framework provides easy portability of optimizing compilers

Deborah S. Coutant

1986-01-01

60

1995 high level synthesis design repository  

Microsoft Academic Search

Abstract: In this paper we briefly describe a set of designs that earn serve as examples for high level synthesis (HLS) systems. The designs vary in complexity from simple behavioral finite state machines to more complex designs such as microprocessors and floating point units. Most of the designs are described in the VHDL language at the behavioral level. We divide

Preeti Ranjan Panda; Nikil D. Dutt

1995-01-01

61

Equilibrium Tides Along with surface gravity waves, the predictable rise and fall of sea level at the coast are  

E-print Network

Equilibrium Tides Along with surface gravity waves, the predictable rise and fall of sea level at the coast are our most familiar periodic motions. These tides do not represent a new class of waves, but rather are the manifestation of strong forcing at precisely repeating periods. Gravitational tide

Thompson, LuAnne

62

A study of the effects of heater size, subcooling, and gravity level on pool boiling heat transfer  

E-print Network

A study of the effects of heater size, subcooling, and gravity level on pool boiling heat transfer Martin Hill, College Park, MD 20742, USA Abstract Pool boiling heat transfer measurements from different. Boiling on three heaters of different size (0.65, 2.62, 7.29 mm2 ) was studied. Control circuitry was used

Kim, Jungho

63

High-Level Application Framework for LCLS  

SciTech Connect

A framework for high level accelerator application software is being developed for the Linac Coherent Light Source (LCLS). The framework is based on plug-in technology developed by an open source project, Eclipse. Many existing functionalities provided by Eclipse are available to high-level applications written within this framework. The framework also contains static data storage configuration and dynamic data connectivity. Because the framework is Eclipse-based, it is highly compatible with any other Eclipse plug-ins. The entire infrastructure of the software framework will be presented. Planned applications and plug-ins based on the framework are also presented.

Chu, P; Chevtsov, S.; Fairley, D.; Larrieu, C.; Rock, J.; Rogind, D.; White, G.; Zalazny, M.; /SLAC

2008-04-22

64

A Fast Full Tensor Gravity computation algorithm for High Resolution 3D Geologic Interpretations  

NASA Astrophysics Data System (ADS)

We present an algorithm to rapidly calculate the vertical gravity and full tensor gravity (FTG) values due to a 3-D geologic model. This algorithm can be implemented on single, multi-core CPU and graphical processing units (GPU) architectures. Our technique is based on the line element approximation with a constant density within each grid cell. This type of parameterization is well suited for high-resolution elevation datasets with grid size typically in the range of 1m to 30m. The large high-resolution data grids in our studies employ a pre-filtered mipmap pyramid type representation for the grid data known as the Geometry clipmap. The clipmap was first introduced by Microsoft Research in 2004 to do fly-through terrain visualization. This method caches nested rectangular extents of down-sampled data layers in the pyramid to create view-dependent calculation scheme. Together with the simple grid structure, this allows the gravity to be computed conveniently on-the-fly, or stored in a highly compressed format. Neither of these capabilities has previously been available. Our approach can perform rapid calculations on large topographies including crustal-scale models derived from complex geologic interpretations. For example, we used a 1KM Sphere model consisting of 105000 cells at 10m resolution with 100000 gravity stations. The line element approach took less than 90 seconds to compute the FTG and vertical gravity on an Intel Core i7 CPU at 3.07 GHz utilizing just its single core. Also, unlike traditional gravity computational algorithms, the line-element approach can calculate gravity effects at locations interior or exterior to the model. The only condition that must be met is the observation point cannot be located directly above the line element. Therefore, we perform a location test and then apply appropriate formulation to those data points. We will present and compare the computational performance of the traditional prism method versus the line element approach on different CPU-GPU system configurations. The algorithm calculates the expected gravity at station locations where the observed gravity and FTG data were acquired. This algorithm can be used for all fast forward model calculations of 3D geologic interpretations for data from airborne, space and submarine gravity, and FTG instrumentation.

Jayaram, V.; Crain, K.; Keller, G. R.

2011-12-01

65

High-resolution gravity survey: Investigation of subsurface structures at Poás volcano, Costa Rica  

NASA Astrophysics Data System (ADS)

Bouguer gravity surveys have long been used to investigate sub-surface density contrasts. The main sources of error in previous surveys have been the determination of relative elevations of stations and the effect of topography (removed via the terrain correction). The availability of high precision Kinematic GPS data now facilitates generation of high-resolution Digital Elevation Models that can help to improve the accuracy of relative elevation determination and the terrain correction. Here we describe a high-resolution gravity survey at Poás volcano, Costa Rica. Our gravity modelling (i) identifies small pockets of magma at shallow depths which relate to successive magma intrusion through time and (ii) shows that the persistent degassing in the eastern part of the crater is related to local deformation at the top of the volcano and changes in the fracture network, rather than to the presence of a shallow magma intrusion.

Fournier, Nicolas; Rymer, Hazel; Williams-Jones, Glyn; Brenes, Jorge

2004-08-01

66

ALTURAS: A MULTI-PURPOSE RUSSET POTATO CULTIVAR WITH HIGH YIELD AND SPECIFIC GRAVITY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Alturas, a late- maturing, high-yielding, russet potato cultivar with high tuber specific gravity, was released in 2002 by the USDA-ARS and the Agricultural Experiment Stations of Idaho, Oregon, and Washington. Originally selected for dehydration processing, its cold-sweetening resistance also make...

67

The University of Maryland Space Systems Laboratory is developing the capability to simulate partial gravity levels  

E-print Network

to the Moon by the end of the next decade. The paper discusses various forms of partial gravity simulation gravity habitat and vehicle design and operations. INTRODUCTION As work begins on hardware for the next structure supports the counterweight system. A further problem involves rotational freedom: a gimbaled

Akin, David

68

Measured and predicted effects of gravity level on directional dendritic solidification of NH4Cl-H2O  

NASA Technical Reports Server (NTRS)

Dendritic growth front rates during vertical directional solidification are predicted for gravity levels of 10 exp 0 g sub e (where e is earth gravity), 10 exp -1 g sub e, 10 exp -2 g sub e, 10 exp -3 g sub e, 10 exp -4 g sub e, and 10 exp -5 g sub e (microgravity) for the physical conditions used for a recent ammonium chloride-water solidification experiment on the International Microgravity Laboratory I (IMLI). The growth front rates at 10 exp 0 g sub e and 10 exp -5 g sub e are validated using ground based laboratory and IMLI experimental data. As the gravity decreases, the growth rates increase until they approach a maximum at approximately 10 exp -4 g sub e. The 10 exp -4 and 10 exp -5 levels are equivalent. Liquid concentration and volume fraction, temperature profiles and fluid flow velocities are also calculated. Kinetic energy calculations for each of the six gravity levels indicate that the threshold for fluid flow to affect the growth front rate is in the range of 10 exp -8 ergs.

Mccay, T. D.; Mccay, Mary H.

1993-01-01

69

Combustion of Gaseous Fuels with High Temperature Air in Normal- and Micro-gravity Conditions  

NASA Technical Reports Server (NTRS)

The objective of this study is determine the effect of air preheat temperature on flame characteristics in normal and microgravity conditions. We have obtained qualitative (global flame features) and some quantitative information on the features of flames using high temperature combustion air under normal gravity conditions with propane and methane as the fuels. This data will be compared with the data under microgravity conditions. The specific focus under normal gravity conditions has been on determining the global flame features as well as the spatial distribution of OH, CH, and C2 from flames using high temperature combustion air at different equivalence ratio.

Wang, Y.; Gupta, A. K.

2001-01-01

70

Very high gravity (VHG) ethanolic brewing and fermentation: a research update.  

PubMed

There have been numerous developments in ethanol fermentation technology since the beginning of the new millennium as ethanol has become an immediate viable alternative to fast-depleting crude reserves as well as increasing concerns over environmental pollution. Nowadays, although most research efforts are focused on the conversion of cheap cellulosic substrates to ethanol, methods that are cost-competitive with gasoline production are still lacking. At the same time, the ethanol industry has engaged in implementing potential energy-saving, productivity and efficiency-maximizing technologies in existing production methods to become more viable. Very high gravity (VHG) fermentation is an emerging, versatile one among such technologies offering great savings in process water and energy requirements through fermentation of higher concentrations of sugar substrate and, therefore, increased final ethanol concentration in the medium. The technology also allows increased fermentation efficiency, without major alterations to existing facilities, by efficient utilization of fermentor space and elimination of known losses. This comprehensive research update on VHG technology is presented in two main sections, namely VHG brewing, wherein the effects of nutrients supplementation, yeast pitching rate, flavour compound synthesis and foam stability under increased wort gravities are discussed; and VHG bioethanol fermentation studies. In the latter section, aspects related to the role of osmoprotectants and nutrients in yeast stress reduction, substrates utilized/tested so far, including saccharide (glucose, sucrose, molasses, etc.) and starchy materials (wheat, corn, barley, oats, etc.), and mash viscosity issues in VHG bioethanol production are detailed. Thereafter, topics common to both areas such as process optimization studies, mutants and gene level studies, immobilized yeast applications, temperature effect, reserve carbohydrates profile in yeast, and economic aspects are discussed and future prospects are summarized. PMID:21695540

Puligundla, Pradeep; Smogrovicova, Daniela; Obulam, Vijaya Sarathi Reddy; Ko, Sanghoon

2011-09-01

71

Future high sea levels in south Sweden  

SciTech Connect

An estimation of future mean high water levels in Oeresund and the southwest Baltic Sea is presented together with a discussion of probable consequences for Falsterbo Peninsula, a trumpet-shaped sandy formation of some 25 km{sup 2} size situated in the very southwest corner of Sweden. A literature review coupled with sea-level measurements and observations made in the area every four hours since October 1945 are given and comprise the base for the present analysis.

Blomgren, S.H.; Hanson, H. [Lund Institute of Technology (Sweden)

1997-12-31

72

A Software Architecture for High Level Applications  

SciTech Connect

A modular software platform for high level applications is under development at the National Synchrotron Light Source II project. This platform is based on client-server architecture, and the components of high level applications on this platform will be modular and distributed, and therefore reusable. An online model server is indispensable for model based control. Different accelerator facilities have different requirements for the online simulation. To supply various accelerator simulators, a set of narrow and general application programming interfaces is developed based on Tracy-3 and Elegant. This paper describes the system architecture for the modular high level applications, the design of narrow and general application programming interface for an online model server, and the prototype of online model server.

Shen,G.

2009-05-04

73

Network-based high level data classification.  

PubMed

Traditional supervised data classification considers only physical features (e.g., distance or similarity) of the input data. Here, this type of learning is called low level classification. On the other hand, the human (animal) brain performs both low and high orders of learning and it has facility in identifying patterns according to the semantic meaning of the input data. Data classification that considers not only physical attributes but also the pattern formation is, here, referred to as high level classification. In this paper, we propose a hybrid classification technique that combines both types of learning. The low level term can be implemented by any classification technique, while the high level term is realized by the extraction of features of the underlying network constructed from the input data. Thus, the former classifies the test instances by their physical features or class topologies, while the latter measures the compliance of the test instances to the pattern formation of the data. Our study shows that the proposed technique not only can realize classification according to the pattern formation, but also is able to improve the performance of traditional classification techniques. Furthermore, as the class configuration's complexity increases, such as the mixture among different classes, a larger portion of the high level term is required to get correct classification. This feature confirms that the high level classification has a special importance in complex situations of classification. Finally, we show how the proposed technique can be employed in a real-world application, where it is capable of identifying variations and distortions of handwritten digit images. As a result, it supplies an improvement in the overall pattern recognition rate. PMID:24806766

Silva, Thiago Christiano; Zhao, Liang

2012-06-01

74

Do we understand high-level vision?  

PubMed

'High-level' vision lacks a single, agreed upon definition, but it might usefully be defined as those stages of visual processing that transition from analyzing local image structure to analyzing structure of the external world that produced those images. Much work in the last several decades has focused on object recognition as a framing problem for the study of high-level visual cortex, and much progress has been made in this direction. This approach presumes that the operational goal of the visual system is to read-out the identity of an object (or objects) in a scene, in spite of variation in the position, size, lighting and the presence of other nearby objects. However, while object recognition as a operational framing of high-level is intuitive appealing, it is by no means the only task that visual cortex might do, and the study of object recognition is beset by challenges in building stimulus sets that adequately sample the infinite space of possible stimuli. Here I review the successes and limitations of this work, and ask whether we should reframe our approaches to understanding high-level vision. PMID:24552691

Cox, David Daniel

2014-04-01

75

High Level Modeling and Evaluation of  

E-print Network

be regarded as an advanced mobile system or service. Therefore, a good analysis of the system requirementsHigh Level Modeling and Evaluation of Multi-Channel Services Thesis for the degree of Philosophiae and Information Science © Shang Gao ISBN 978-82-471-2702-5 (printed ver.) ISBN 978-82-471-2703-2 (electronic ver

76

High-level radioactive wastes. Supplement 1  

SciTech Connect

This bibliography contains information on high-level radioactive wastes included in the Department of Energy's Energy Data Base from August 1982 through December 1983. These citations are to research reports, journal articles, books, patents, theses, and conference papers from worldwide sources. Five indexes, each preceded by a brief description, are provided: Corporate Author, Personal Author, Subject, Contract Number, and Report Number. 1452 citations.

McLaren, L.H. (ed.)

1984-09-01

77

PAIRWISE BLENDING OF HIGH LEVEL WASTE (HLW)  

SciTech Connect

The primary objective of this study is to demonstrate a mission scenario that uses pairwise and incidental blending of high level waste (HLW) to reduce the total mass of HLW glass. Secondary objectives include understanding how recent refinements to the tank waste inventory and solubility assumptions affect the mass of HLW glass and how logistical constraints may affect the efficacy of HLW blending.

CERTA, P.J.

2006-02-22

78

Isolation and Characterization of Brewer's Yeast Variants with Improved Fermentation Performance under High-Gravity Conditions?  

PubMed Central

To save energy, space, and time, today's breweries make use of high-gravity brewing in which concentrated medium (wort) is fermented, resulting in a product with higher ethanol content. After fermentation, the product is diluted to obtain beer with the desired alcohol content. While economically desirable, the use of wort with an even higher sugar concentration is limited by the inability of brewer's yeast (Saccharomyces pastorianus) to efficiently ferment such concentrated medium. Here, we describe a successful strategy to obtain yeast variants with significantly improved fermentation capacity under high-gravity conditions. We isolated better-performing variants of the industrial lager strain CMBS33 by subjecting a pool of UV-induced variants to consecutive rounds of fermentation in very-high-gravity wort (>22° Plato). Two variants (GT336 and GT344) showing faster fermentation rates and/or more-complete attenuation as well as improved viability under high ethanol conditions were identified. The variants displayed the same advantages in a pilot-scale stirred fermenter under high-gravity conditions at 11°C. Microarray analysis identified several genes whose altered expression may be responsible for the superior performance of the variants. The role of some of these candidate genes was confirmed by genetic transformation. Our study shows that proper selection conditions allow the isolation of variants of commercial brewer's yeast with superior fermentation characteristics. Moreover, it is the first study to identify genes that affect fermentation performance under high-gravity conditions. The results are of interest to the beer and bioethanol industries, where the use of more-concentrated medium is economically advantageous. PMID:17158628

Blieck, Lies; Toye, Geert; Dumortier, Françoise; Verstrepen, Kevin J.; Delvaux, Freddy R.; Thevelein, Johan M.; Van Dijck, Patrick

2007-01-01

79

Accurate Gravities of F, G, and K stars from High Resolution Spectra Without External Constraints  

E-print Network

We demonstrate a new procedure to derive accurate and precise surface gravities from high resolution spectra without the use of external constraints. Our analysis utilizes Spectroscopy Made Easy (SME) with robust spectral line constraints and uses an iterative process to mitigate degeneracies in the fitting process. We adopt an updated radiative transfer code, a new treatment for neutral perturber broadening, a line list with multiple gravity constraints and separate fitting for global stellar properties and abundance determinations. To investigate the sources of temperature dependent trends in determining log g noted in previous studies, we obtained Keck HIRES spectra of 42 Kepler asteroseismic stars. In comparison to asteroseismically determined log g our spectroscopic analysis has a constant offset of 0.01 dex with a root mean square (RMS) scatter of 0.05 dex. We also analyzed 30 spectra which had published surface gravities determined using the $a/R_*$ technique from planetary transits and found a constan...

Brewer, John M; Basu, Sarbani; Valenti, Jeff A; Piskunov, Nikolai

2015-01-01

80

Gravity Fountains  

NSDL National Science Digital Library

This activity (located on page 3 of the PDF) is a full inquiry investigation into the forces of gravity and air pressure. Groups of learners will construct a simple gravity fountain by making a hole near the bottom of a 2-liter bottle, filling it with water, then as the bottle empties, collecting measurements of the water levels and length of the stream, to make a graph for analysis. Relates to linked video, DragonflyTV GPS: Gravity Fountain.

Twin Cities Public Television, Inc.

2007-01-01

81

Python based high-level synthesis compiler  

NASA Astrophysics Data System (ADS)

This paper presents a python based High-Level synthesis (HLS) compiler. The compiler interprets an algorithmic description of a desired behavior written in Python and map it to VHDL. FPGA combines many benefits of both software and ASIC implementations. Like software, the mapped circuit is flexible, and can be reconfigured over the lifetime of the system. FPGAs therefore have the potential to achieve far greater performance than software as a result of bypassing the fetch-decode-execute operations of traditional processors, and possibly exploiting a greater level of parallelism. Creating parallel programs implemented in FPGAs is not trivial. This article describes design, implementation and first results of created Python based compiler.

Cieszewski, Rados?aw; Pozniak, Krzysztof; Romaniuk, Ryszard

2014-11-01

82

Compositional variations in the undercooled Pb-Sn eutectic solidified at various acceleration levels. [low gravity manufacturing  

NASA Technical Reports Server (NTRS)

Ingots of Pb-61.9 Sn were undercooled and solidified under increasing gravity levels in order to investigate the effects of segregation. The onset of convective flow subsequent to the nucleation of lead is demonstrated. It is shown that when material system in the molten state contains constituents of varying densities, the combination of gravitational forces on the nucleating species and the amount of undercooling of the melt will determine the resultant segregation.

Johnston, M. H.; Griner, S.

1977-01-01

83

Onset of Soret-driven convection of binary fluid in square cavity heated from above at different gravity levels  

NASA Astrophysics Data System (ADS)

The instability of incompressible viscous binary fluid with the Soret effect in square cavity heated from above is studied for different gravity levels. The no slip and zero mass flux conditions are imposed on all the boundaries. The horizontal boundaries are perfectly conductive, they are maintained at constant different temperatures and vertical boundaries are adiabatic. The calculations are performed for water - isopropanol mixture 90:10. Initial conditions correspond to the motionless state with uniform distribution of components and uniform temperature gradient directed upward. For binary fluid under consideration the separation parameter is negative therefore the Soret effect leads to the accumulation of heavy component in the upper part of cavity, moreover, the rate of accumulation is independent of the gravity level. The linear stability of the unsteady motionless state is studied numerically by solving linearized equations for small perturbations. To determine the time t* for the onset of instability, the criterion suggested in [1] is used. The dependence of t* on the gravity level is obtained. The work was done under financial support of Government of Perm Region, Russia (Contract C-26/212). 1. Shliomis M.I., Souhar M. Europhysics Letters. 2000. Vol. 49 (1), pp. 55-61.

Lyubimova, Tatyana; Zubova, Nadezhda

84

Communicators for high-noise-level environments  

NASA Astrophysics Data System (ADS)

At the request of the U.S. Geological Survey, the feasibility of equipping workers with a two-way communications system built into a construction hard hat for use in an extremely high ambient noise level has been investigated. As a result, several systems were tested on an offshore oil platform in the Gulf of Mexico. The investigation indicates that a simple modification of a commercial low-power, frequency modulated system operating in the 49-MHz public service band could be used to considerable advantage. Penetration through platform structures was excellent, and communication was possible from within an enclosed steel compressor room where noise levels were as high as 97 dBA to all points on the platform.

Shoemaker, R. F.; Harrison, E. H.

1981-04-01

85

High-Level Waste Melter Study Report  

SciTech Connect

At the Hanford Site in Richland, Washington, the path to site cleanup involves vitrification of the majority of the wastes that currently reside in large underground tanks. A Joule-heated glass melter is the equipment of choice for vitrifying the high-level fraction of these wastes. Even though this technology has general national and international acceptance, opportunities may exist to improve or change the technology to reduce the enormous cost of accomplishing the mission of site cleanup. Consequently, the U.S. Department of Energy requested the staff of the Tanks Focus Area to review immobilization technologies, waste forms, and modifications to requirements for solidification of the high-level waste fraction at Hanford to determine what aspects could affect cost reductions with reasonable long-term risk. The results of this study are summarized in this report.

Perez, Joseph M.; Bickford, Dennis F.; Day, Delbert E.; Kim, Dong-Sang; Lambert, Steven L.; Marra, Sharon L.; Peeler, David K.; Strachan, Denis M.; Triplett, Mark B.; Vienna, John D.; Wittman, Richard S.

2001-07-13

86

High-Level Waste Melter Review  

SciTech Connect

The U.S. Department of Energy (DOE) is faced with a massive cleanup task in resolving the legacy of environmental problems from years of manufacturing nuclear weapons. One of the major activities within this task is the treatment and disposal of the extremely large amount of high-level radioactive (HLW) waste stored at the Hanford Site in Richland, Washington. The current planning for the method of choice for accomplishing this task is to vitrify (glassify) this waste for disposal in a geologic repository. This paper describes the results of the DOE-chartered independent review of alternatives for solidification of Hanford HLW that could achieve major cost reductions with reasonable long-term risks, including recommendations on a path forward for advanced melter and waste form material research and development. The potential for improved cost performance was considered to depend largely on increased waste loading (fewer high-level waste canisters for disposal), higher throughput, or decreased vitrification facility size.

Ahearne, J.; Gentilucci, J.; Pye, L. D.; Weber, T.; Woolley, F.; Machara, N. P.; Gerdes, K.; Cooley, C.

2002-02-26

87

Management of high-level nuclear wastes  

Microsoft Academic Search

A brief review is given of significant developments in the management of high-level nuclear wastes since the Oct. 1976 first Pacific Basin Conference on Nuclear Power Development and the Fuel Cycle. Emphasis is on policy and technical developments in the U.S., with some attention paid to developments in other countries that have impacted technical direction in the U.S. Spent fuel

A. M. Platt; J. L. McElroy

1978-01-01

88

GTOOLS: an Interactive Computer Program to Process Gravity Data for High-Resolution Applications  

NASA Astrophysics Data System (ADS)

An interactive computer program, GTOOLS, has been developed to process gravity data acquired by the Scintrex CG-5 and LaCoste & Romberg EG, G and D gravity meters. The aim of GTOOLS is to provide a validated methodology for computing relative gravity values in a consistent way accounting for as many environmental factors as possible (e.g., tides, ocean loading, solar constraints, etc.), as well as instrument drift. The program has a modular architecture. Each processing step is implemented in a tool (function) that can be either run independently or within an automated task. The tools allow the user to (a) read the gravity data acquired during field surveys completed using different types of gravity meters; (b) compute Earth tides using an improved version of Longman's (1959) model; (c) compute ocean loading using the HARDISP code by Petit and Luzum (2010) and ocean loading harmonics from the TPXO7.2 ocean tide model; (d) estimate the instrument drift using linear functions as appropriate; and (e) compute the weighted least-square-adjusted gravity values and their errors. The corrections are performed up to microGal ( ?Gal) precision, in accordance with the specifications of high-resolution surveys. The program has the ability to incorporate calibration factors that allow for surveys done using different gravimeters to be compared. Two additional tools (functions) allow the user to (1) estimate the instrument calibration factor by processing data collected by a gravimeter on a calibration range; (2) plot gravity time-series at a chosen benchmark. The interactive procedures and the program output (jpeg plots and text files) have been designed to ease data handling and archiving, to provide useful information for future data interpretation or modeling, and facilitate comparison of gravity surveys conducted at different times. All formulas have been checked for typographical errors in the original reference. GTOOLS, developed using Matlab, is open source and machine independent. We will demonstrate program use and utility with data from multiple microgravity surveys at Kilauea volcano, Hawai'i.

Battaglia, M.; Poland, M. P.; Kauahikaua, J. P.

2012-12-01

89

Influence of high gravity process conditions on the environmental impact of ethanol production from wheat straw.  

PubMed

Biofuel production processes at high gravity are currently under development. Most of these processes however use sugars or first generation feedstocks as substrate. This paper presents the results of a life cycle assessment (LCA) of the production of bio-ethanol at high gravity conditions from a second generation feedstock, namely, wheat straw. The LCA used lab results of a set of 36 process configurations in which dry matter content, enzyme preparation and loading, and process strategy were varied. The LCA results show that higher dry matter content leads to a higher environmental impact of the ethanol production, but this can be compensated by reducing the impact of enzyme production and use, and by polyethylene glycol addition at high dry matter content. The results also show that the renewable and non-renewable energy use resulting from the different process configurations ultimately determine their environmental impact. PMID:25299491

Janssen, Matty; Tillman, Anne-Marie; Cannella, David; Jørgensen, Henning

2014-12-01

90

Curvature Oscillations in Modified Gravity and High Energy Cosmic Rays  

E-print Network

It is shown that F(R)-modified gravitational theories lead to curvature oscillations in astrophysical systems with rising energy density. The frequency and the amplitude of such oscillations could be very high and would lead to noticeable production of energetic cosmic ray particles.

E. V. Arbuzova; A. D. Dolgov; L. Reverberi

2012-11-24

91

High-resolution numerical modeling of wave-supported gravity-driven mudflows  

NASA Astrophysics Data System (ADS)

Wave-supported gravity-driven mudflow has been identified as a major offshore fine sediment transport mechanism of terrestrial sediment into the coastal ocean. This transport process essentially occurs within the wave boundary layer. In this study, wave-supported gravity-driven mudflow is investigated via a wave-phase-resolving high-resolution numerical model for fluid mud transport. The model results are verified with field observation of sediment concentration and near-bed flow velocities at Po prodelta. The characteristics of wave-supported gravity-driven mudflows are diagnosed by varying the bed erodibility, floc properties (fractal dimension), and rheological stresses in the numerical simulations. Model results for moderate concentration suggest that using an appropriately specified fractal dimension, the dynamics of wave-supported gravity-driven mudflow can be predicted without explicitly incorporating rheological stress. However, incorporating rheological stress makes the results less sensitive to prescribed fractal dimension. For high-concentration conditions, it is necessary to incorporate rheological stress in order to match observed intensity of downslope gravity-driven current. Model results are further analyzed to evaluate and calibrate simple parameterizations. Analysis suggests that when neglecting rheological stress, the drag coefficient decreases with increasing wave intensity and seems to follow a power law. However, when rheological stress is incorporated, the resulting drag coefficient is more or less constant (around 0.0013) for different wave intensities. Model results further suggest the bulk Richardson number has a magnitude smaller than 0.25 and is essentially determined by the amount of available soft mud (i.e., the erodibility), suggesting a supply limited condition for unconsolidated mud.

Hsu, Tian-Jian; Ozdemir, Celalettin E.; Traykovski, Peter A.

2009-05-01

92

Synoptic-scale variability of arctic gravity wave activity during summer and potential impacts on the high latitude middle atmosphere  

NASA Astrophysics Data System (ADS)

Although the role of gravity waves in the global atmospheric circulation is generally understood, discussion of synoptic gravity wave activity, especially pertaining to high latitude summer environments, is lacking in the literature. Tropospherically generated gravity waves greatly contribute to the zonal drag necessary to induce meridional outflow and subsequent upwelling observed in the adiabatically cooled summer mesosphere, ultimately resulting in an environment conducive to mesospheric cloud formation. However, the very gravity wave activity responsible for this induced cooling is also believed to be a major source of variability on mesospheric clouds over shorter time scales, and this topic should be of considerable interest if such clouds are to be used as tracers of the global climate. It is therefore the purpose of this thesis to explore high latitude synoptic gravity wave activity and ultimately seek an understanding of the associated influence on overlaying summer mesospheric clouds. Another goal is to better understand and account for potential variability in high latitude middle and upper atmospheric measurements that can be directly associated with "weather conditions" at lower altitudes. These endeavors are addressed through Rayleigh/aerosol lidar data obtained from the ARCtic LIdar TEchnology (ARCLITE) facility located at Sondrestrom, Greenland (67°N, 310°E), global tropospheric and stratospheric analyses and forecasts, and the Gravity-wave Regional Or Global RAy Tracer (GROGRAT) model. In this study we are able to show that (a) the upper stratospheric gravity wave strength and the brightness of overlaying mesospheric clouds, as measured by representative field proxies, are negatively correlated over time scales of less than a day, (b) such upper stratospheric gravity wave variability is inversely related to mesospheric cloud variability on time scales of ˜1 to 4 hours, (c) gravity wave hindcasts faithfully reproduce experimental lidar observations taken over the month of August 1996, (d) the observed upper stratospheric gravity wave activity is shown to originate from regionalized, non-orographic sources in the troposphere, (e) such gravity wave activity can propagate through the middle atmosphere, potentially impacting overlaying mesospheric clouds, and (f) the forecasting of such upper stratospheric gravity wave activity, and therefore the corresponding mesospheric cloud activity, is feasible. In conclusion, the results herein provide additional evidence of gravity wave influence on mesospheric clouds, a step towards the forecasting of regional gravity wave activity, and ultimately a better understanding of synoptic gravity wave activity at high latitudes.

Gerrard, Andrew John

93

Exploration of Anomalous Gravity Effects by rf-Pumped Magnetized High-T(c) Superconducting Oxides  

NASA Technical Reports Server (NTRS)

A number of anomalous gravitational effects have been reported in the scientific literature during recent years, but there has been no independent confirmation with regard to any of these claims. Therefore, the NASA Marshall Space Flight Center, in response to the propulsion challenges specified by NASA's Breakthrough Propulsion Physics (BPP) program, proposed to explore the possibility of observing anomalous gravitation behavior through the manipulation of Josephson junction effects in magnetized high-Tc superconducting oxides. The technical goal was to critically test this revolutionary physical claim and provide a rigorous, independent, empirical confirmation (or refutation) of anomalous effects related to the manipulation of gravity by radio frequency (rf)-pumped magnetized type-2 superconductors. Because the current empirical evidence for gravity modification is anecdotal, our objective was to design, construct, and meticulously implement a discriminating experiment, which would put these observations on a more firm footing within the scientific community. Our approach is unique in that we advocate the construction of an extremely sensitive torsion balance with which to measure gravity modification effects by rf-pumped type-2 superconductor test masses. This paper reviews the anecdotal evidence for anomalous gravity effects, describes the design and development of a simplified torsion balance experiment for empirically investigating these claims, and presents the results of preliminary experiments.

Robertson, Tony; Litchford, Ron; Peters, Randall; Thompson, Byran; Rodgers, Stephen L. (Technical Monitor)

2001-01-01

94

40 CFR 227.30 - High-level radioactive waste.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false High-level radioactive waste. 227.30 Section 227.30 Protection... Definitions § 227.30 High-level radioactive waste. High-level radioactive waste means the aqueous waste resulting...

2010-07-01

95

40 CFR 227.30 - High-level radioactive waste.  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false High-level radioactive waste. 227.30 Section 227.30 Protection... Definitions § 227.30 High-level radioactive waste. High-level radioactive waste means the aqueous waste resulting...

2011-07-01

96

40 CFR 227.30 - High-level radioactive waste.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false High-level radioactive waste. 227.30 Section 227.30 Protection... Definitions § 227.30 High-level radioactive waste. High-level radioactive waste means the aqueous waste resulting...

2013-07-01

97

40 CFR 227.30 - High-level radioactive waste.  

Code of Federal Regulations, 2014 CFR

... 2014-07-01 false High-level radioactive waste. 227.30 Section 227.30 Protection... Definitions § 227.30 High-level radioactive waste. High-level radioactive waste means the aqueous waste resulting...

2014-07-01

98

EAP high-level product architecture  

NASA Astrophysics Data System (ADS)

EAP technology has the potential to be used in a wide range of applications. This poses the challenge to the EAP component manufacturers to develop components for a wide variety of products. Danfoss Polypower A/S is developing an EAP technology platform, which can form the basis for a variety of EAP technology products while keeping complexity under control. High level product architecture has been developed for the mechanical part of EAP transducers, as the foundation for platform development. A generic description of an EAP transducer forms the core of the high level product architecture. This description breaks down the EAP transducer into organs that perform the functions that may be present in an EAP transducer. A physical instance of an EAP transducer contains a combination of the organs needed to fulfill the task of actuator, sensor, and generation. Alternative principles for each organ allow the function of the EAP transducers to be changed, by basing the EAP transducers on a different combination of organ alternatives. A model providing an overview of the high level product architecture has been developed to support daily development and cooperation across development teams. The platform approach has resulted in the first version of an EAP technology platform, on which multiple EAP products can be based. The contents of the platform have been the result of multi-disciplinary development work at Danfoss PolyPower, as well as collaboration with potential customers and research institutions. Initial results from applying the platform on demonstrator design for potential applications are promising. The scope of the article does not include technical details.

Gudlaugsson, T. V.; Mortensen, N. H.; Sarban, R.

2013-04-01

99

The effects of high level infrasound  

SciTech Connect

This paper will attempt to survey the current knowledge on the effects of relative high levels of infrasound on humans. While this conference is concerned mainly about hearing, some discussion of other physiological effects is appropriate. Such discussion also serves to highlight a basic question, 'Is hearing the main concern of infrasound and low frequency exposure, or is there a more sensitive mechanism'. It would be comforting to know that the focal point of this conference is indeed the most important concern. Therefore, besides hearing loss and auditory threshold of infrasonic and low frequency exposure, four other effects will be provided. These are performance, respiration, annoyance, and vibration.

Johnson, D.L.

1980-02-01

100

Service Oriented Architecture for High Level Applications  

SciTech Connect

Standalone high level applications often suffer from poor performance and reliability due to lengthy initialization, heavy computation and rapid graphical update. Service-oriented architecture (SOA) is trying to separate the initialization and computation from applications and to distribute such work to various service providers. Heavy computation such as beam tracking will be done periodically on a dedicated server and data will be available to client applications at all time. Industrial standard service architecture can help to improve the performance, reliability and maintainability of the service. Robustness will also be improved by reducing the complexity of individual client applications.

Chu, Chungming; Chevtsov, Sergei; Wu, Juhao; /SLAC; Shen, Guobao; /Brookhaven

2012-06-28

101

Venus gravity  

NASA Technical Reports Server (NTRS)

The anomalous gravity field of Venus shows high correlation with surface features revealed by radar. We extract gravity models from the Doppler tracking data from the Pioneer Venus Orbiter (PVO) by means of a two-step process. In the first step, we solve the nonlinear spacecraft state estimation problem using a Kalman filter-smoother. The Kalman filter was evaluated through simulations. This evaluation and some unusual features of the filter are discussed. In the second step, we perform a geophysical inversion using a linear Bayesian estimator. To allow an unbiased comparison between gravity and topography, we use a simulation technique to smooth and distort the radar topographic data so as to yield maps having the same characteristics as our gravity maps. The maps presented cover 2/3 of the surface of Venus and display the strong topography-gravity correlation previously reported. The topography-gravity scatter plots show two distinct trends.

Reasenberg, Robert D.

1993-01-01

102

Technetium Chemistry in High-Level Waste  

SciTech Connect

Tc contamination is found within the DOE complex at those sites whose mission involved extraction of plutonium from irradiated uranium fuel or isotopic enrichment of uranium. At the Hanford Site, chemical separations and extraction processes generated large amounts of high level and transuranic wastes that are currently stored in underground tanks. The waste from these extraction processes is currently stored in underground High Level Waste (HLW) tanks. However, the chemistry of the HLW in any given tank is greatly complicated by repeated efforts to reduce volume and recover isotopes. These processes ultimately resulted in mixing of waste streams from different processes. As a result, the chemistry and the fate of Tc in HLW tanks are not well understood. This lack of understanding has been made evident in the failed efforts to leach Tc from sludge and to remove Tc from supernatants prior to immobilization. Although recent interest in Tc chemistry has shifted from pretreatment chemistry to waste residuals, both needs are served by a fundamental understanding of Tc chemistry.

Hess, Nancy J.

2006-06-01

103

High accuracy electronic material level sensor  

DOEpatents

The High Accuracy Electronic Material Level Sensor (electronic dipstick) is a sensor based on time domain reflectometry (TDR) of very short electrical pulses. Pulses are propagated along a transmission line or guide wire that is partially immersed in the material being measured; a launcher plate is positioned at the beginning of the guide wire. Reflected pulses are produced at the material interface due to the change in dielectric constant. The time difference of the reflections at the launcher plate and at the material interface are used to determine the material level. Improved performance is obtained by the incorporation of: (1) a high accuracy time base that is referenced to a quartz crystal, (2) an ultrawideband directional sampler to allow operation without an interconnect cable between the electronics module and the guide wire, (3) constant fraction discriminators (CFDs) that allow accurate measurements regardless of material dielectric constants, and reduce or eliminate errors induced by triple-transit or ``ghost`` reflections on the interconnect cable. These improvements make the dipstick accurate to better than 0.1%. 4 figs.

McEwan, T.E.

1997-03-11

104

High accuracy electronic material level sensor  

DOEpatents

The High Accuracy Electronic Material Level Sensor (electronic dipstick) is a sensor based on time domain reflectometry (TDR) of very short electrical pulses. Pulses are propagated along a transmission line or guide wire that is partially immersed in the material being measured; a launcher plate is positioned at the beginning of the guide wire. Reflected pulses are produced at the material interface due to the change in dielectric constant. The time difference of the reflections at the launcher plate and at the material interface are used to determine the material level. Improved performance is obtained by the incorporation of: 1) a high accuracy time base that is referenced to a quartz crystal, 2) an ultrawideband directional sampler to allow operation without an interconnect cable between the electronics module and the guide wire, 3) constant fraction discriminators (CFDs) that allow accurate measurements regardless of material dielectric constants, and reduce or eliminate errors induced by triple-transit or "ghost" reflections on the interconnect cable. These improvements make the dipstick accurate to better than 0.1%.

McEwan, Thomas E. (Livermore, CA)

1997-01-01

105

A Comparison of Airborne Gravity Data with High Quality Ground Truth over the Kauring Test Range  

NASA Astrophysics Data System (ADS)

Airborne gravity measurements have been continually improving over the last decade, however direct comparison with ground gravity data has proven to be problematic due largely to inconsistencies in the ground data. There exists now however a test range in Western Australia, the Kauring Airborne Gravity Test Site, which has been very carefully surveyed with land gravimeters (among other measurements) for the purpose of making comparisons between airborne gravimetry and gradiometry results and the ground data. Sander Geophysics Limited (SGL) conducted a fixed-wing high-resolution gravimetric survey over this test site for the Victoria State Department of Primary Industries as part of the CarbonNet Project. The survey was flown using SGL's airborne gravity system, AIRGrav (Airborne Inertially Referenced Gravimeter). The survey area is divided into an approximately 5 Km by 5 Km inner "AGG" area and a surrounding 20 Km by 20 Km "AG" area. The area is gently rolling with elevations ranging from approximately 200 to 400 m. For the SGL survey the AG area was covered by lines flown North-South at a spacing of 200 m with control lines at a 2 Km spacing, while the AGG area was covered by lines flown Northwest-Southeast at a spacing of 50 m. The survey followed a draped elevation model with a target ground clearance of 80 m, and the target ground speed was 45 m/sec. In this presentation, the airborne gravity results will be compared with the ground data, including a comparison of the horizontal components (or deflections of the vertical) obtained from the AIRGrav system with the latest available Australian geoid model. Techniques to combine the horizontal components with the vertical to improve resolution will also be presented.

Ferguson, S.

2013-12-01

106

Improved High-Resolution Lunar Gravity Field Model From SELENE and Historical Tracking Data  

NASA Astrophysics Data System (ADS)

The Kaguya (SELENE) mission (September 2007 - June 2009) consisted of three separate satellites, which were tracked by a variety of terrestrial based tracking systems for the purpose of precision orbit determination and lunar gravity field determination. In addition to standard two-way Doppler and range tracking, Kaguya also carried out 4-way Doppler tracking between the sub-satellite Rstar and the main orbiter while the latter was over the far side of the Moon, and differential VLBI tracking between the two sub-satellites Rstar and Vstar. Kaguya data have been combined with historical tracking data of lunar orbiters (up to Lunar Prospector), and this has resulted in lunar gravity field models expressed in spherical harmonics up to a maximum resolution of degree and order 100. These models mapped the far side gravity field of the Moon for the first time, and helped improve the estimates of the lower degrees. Here, we present an improved, high-resolution lunar gravity field model, expressed in spherical harmonics up to degree and order 150. Our analysis differs in several crucial aspects from our previous models: we have now included the complete Lunar Prospector tracking data set, including data from the extended mission; we also included switching differential VLBI data instead of same-beam data only, which helps to further improve the orbit precision of both sub-satellites; and we extended the arc lengths of both Lunar Prospector (nominal mission only, from 2 days to 4 days, by virtue of having mapped the far side gravity field) and the main satellite of Kaguya (from 12 hours to arc lengths varying between 2 days and 1 week, by virtue of careful modelling of the angular momentum desaturation manoeuvres). The result is a model with smaller formal errors for the lower degrees, and an especially improved orbit prediction performance. Orbit propagation from an initial two-day data arc, at an average altitude of 50 km, results in orbit errors of 110 m after one month, whereas previous lunar gravity models of the same expansion produce orbit errors of 500 m and larger. Improvements are especially seen in the along-track component. With the far side gravity field included, we expect that this model is especially useful for the upcoming GRAIL mission.

Goossens, S. J.; Matsumoto, K.; Kikuchi, F.; Liu, Q.; Hanada, H.; Lemoine, F. G.; Rowlands, D. D.; Ishihara, Y.; Noda, H.; Namiki, N.; Iwata, T.; Sasaki, S.

2011-12-01

107

Einstein Gravity from Conformal Gravity  

E-print Network

We show that that four dimensional conformal gravity plus a simple Neumann boundary condition can be used to get the semiclassical (or tree level) wavefunction of the universe of four dimensional asymptotically de-Sitter or Euclidean anti-de Sitter spacetimes. This simple Neumann boundary condition selects the Einstein solution out of the more numerous solutions of conformal gravity. It thus removes the ghosts of conformal gravity from this computation. In the case of a five dimensional pure gravity theory with a positive cosmological constant we show that the late time superhorizon tree level probability measure, $|\\Psi [ g ]|^2$, for its four dimensional spatial slices is given by the action of Euclidean four dimensional conformal gravity.

Juan Maldacena

2011-06-09

108

Reusable and Extensible High Level Data Distributions  

NASA Technical Reports Server (NTRS)

This paper presents a reusable design of a data distribution framework for data parallel high performance applications. We are implementing the design in the context of the Chapel high productivity programming language. Distributions in Chapel are a means to express locality in systems composed of large numbers of processor and memory components connected by a network. Since distributions have a great effect on,the performance of applications, it is important that the distribution strategy can be chosen by a user. At the same time, high productivity concerns require that the user is shielded from error-prone, tedious details such as communication and synchronization. We propose an approach to distributions that enables the user to refine a language-provided distribution type and adjust it to optimize the performance of the application. Additionally, we conceal from the user low-level communication and synchronization details to increase productivity. To emphasize the generality of our distribution machinery, we present its abstract design in the form of a design pattern, which is independent of a concrete implementation. To illustrate the applicability of our distribution framework design, we outline the implementation of data distributions in terms of the Chapel language.

Diaconescu, Roxana E.; Chamberlain, Bradford; James, Mark L.; Zima, Hans P.

2005-01-01

109

CRYSTALLIZATION IN HIGH-LEVEL WASTE GLASSES U.S. DEPARTMENT OF ENERGY OFFICE OF RIVER PROTECTION WTP ENGINEERING DIVISION  

Microsoft Academic Search

Various circumstances influence crystallization in glassmaking, for example: (1) crystals nucleate and grow before the glass-forming melt occurs; (2) crystals grow or dissolve in flowing melt and during changing temperature; (3) crystals move under the influence of gravity; (4) crystals agglomerate and interact with gas bubbles; (5) high-level wastes (HLW) are mixtures of a large number of components in unusual

KRUGER AA; HRMA PR

2009-01-01

110

Airway injury during high-level exercise.  

PubMed

Airway epithelial cells act as a physical barrier against environmental toxins and injury, and modulate inflammation and the immune response. As such, maintenance of their integrity is critical. Evidence is accumulating to suggest that exercise can cause injury to the airway epithelium. This seems the case particularly for competitive athletes performing high-level exercise, or when exercise takes place in extreme environmental conditions such as in cold dry air or in polluted air. Dehydration of the small airways and increased forces exerted on to the airway surface during severe hyperpnoea are thought to be key factors in determining the occurrence of injury of the airway epithelium. The injury-repair process of the airway epithelium may contribute to the development of the bronchial hyper-responsiveness that is documented in many elite athletes. PMID:22247295

Kippelen, Pascale; Anderson, Sandra D

2012-05-01

111

Effective actions for high energy processes in QCD and in quantum gravity  

NASA Astrophysics Data System (ADS)

The Gribov approach to the hadron-hadron high energy scattering is based on an effective field theory for Pomerons. We construct similar effective actions for gluons and gravitons in QCD and in gravity. The BFKL approach in QCD is reviewed and presented in the form of the gauge-invariant effective theory for the interactions local in the particle rapidities. An analogous generally covariant action for gravity is formulated in terms of effective currents satisfying the Hamilton-Jacobi equation. It gives a possibility to construct various effective vertices and graviton j-plane trajectory. In the N = 4 extended supersymmetric gauge model such effective action in the 10-dimensional anti-de-Sitter space can be used for the description of the Pomeron interactions.

Lipatov, L. N.

2013-07-01

112

Research on reaction zone structure of high-press gravity-independent singlet oxygen generator  

NASA Astrophysics Data System (ADS)

High press, gravity-independent, singlet oxygen generator (HGSOG) [1] with small reaction zone and high chemical efficiency was designed and fabricated. The mixing, reaction and separation processes happened simultaneously in the reaction zone of HGSOG. The size and the configuration of reaction zone are very important for HGSOG. In this paper, p-? value was calculated to determine the upper limit of the volume of reaction zone. The condition of gas-liquid separation was calculated to determine the lower limit of the volume of reaction zone. The utilization rate of Cl2 achieved 90% and the yield of O2(1?) reached 70%.

Liu, Yushi; Chen, Wenwu; Wang, Jinglong; Xu, Xiaobo; Liu, Zhendong; Ke, Changchun; Guo, Jingwei; Zhang, Shaoqian; Jin, Yuqi; Sang, Fengting

2015-02-01

113

Probing low-scale quantum gravity with high-energy neutrinos  

SciTech Connect

Motivated by the quantum structure of space-time at high scales M{sub QG}, we study the propagation behavior of the high-energy neutrino within the quantum gravity effect. We consider the possible induced dispersive effect and derive the resulting vacuum refraction index {eta}{sub vac}(E{sub {nu}}) Asymptotically-Equal-To 1 + E{sub {nu}}{sup 2}/M{sub QG}{sup 2}. Then, by referring to the SN1987A and basing on the recorded neutrino data we approach the corresponding scale M{sub QG} Asymptotically-Equal-To 10{sup 4} GeV.

Ennadifi, Salah Eddine, E-mail: ennadifis@gmail.com [University Mohammed V-Agdal, Laboratory of High Energy Physics, Modeling and Simulation, Faculty of Science (Morocco)

2013-05-15

114

Three-dimensional transient simulation of Marangoni flow in a cylindrical enclosure under various gravity levels  

NASA Astrophysics Data System (ADS)

A numerical study is undertaken of the interaction between natural convection and Marangoni flow in a vertical cylindrical enclosure of aspect ratio 1, which has an adiabatic free lateral face and isothermal top and bottom walls. The 3D transient code uses a hybrid finite-difference scheme on a staggered grid with explicit time-steps, and an iterative pressure-velocity coupling. The flow patterns and isotherms are found to remain qualitatively unchanged in different gravity environments, and no significant disturbance of the axially symmetric flow mode is observed.

Marek, R.; Straub, J.

115

Effects of Varying Gravity Levels on fNIRS Headgear Performance and Signal Recovery  

NASA Technical Reports Server (NTRS)

This paper reviews the effects of varying gravitational levels on functional Near-Infrared Spectroscopy (fNIRS) headgear. The fNIRS systems quantify neural activations in the cortex by measuring hemoglobin concentration changes via optical intensity. Such activation measurement allows for the detection of cognitive state, which can be important for emotional stability, human performance and vigilance optimization, and the detection of hazardous operator state. The technique depends on coupling between the fNIRS probe and users skin. Such coupling may be highly susceptible to motion if probe-containing headgear designs are not adequately tested. The lack of reliable and self-applicable headgear robust to the influence of motion artifact currently inhibits its operational use in aerospace environments. Both NASAs Aviation Safety and Human Research Programs are interested in this technology as a method of monitoring cognitive state of pilots and crew.

Mackey, Jeffrey R.; Harrivel, Angela R.; Adamovsky, Grigory; Lewandowski, Beth E.; Gotti, Daniel J.; Tin, Padetha; Floyd, Bertram M.

2013-01-01

116

Viscosity Measurement of Highly Viscous Liquids Using Drop Coalescence in Low Gravity  

NASA Technical Reports Server (NTRS)

The method of drop coalescence is being investigated for use as a method for determining the viscosity of highly viscous undercooled liquids. Low gravity environment is necessary in this case to minimize the undesirable effects of body forces and liquid motion in levitated drops. Also, the low gravity environment will allow for investigating large liquid volumes which can lead to much higher accuracy for the viscosity calculations than possible under 1 - g conditions. The drop coalescence method is preferred over the drop oscillation technique since the latter method can only be applied for liquids with vanishingly small viscosities. The technique developed relies on both the highly accurate solution of the Navier-Stokes equations as well as on data from experiments conducted in near zero gravity environment. In the analytical aspect of the method two liquid volumes are brought into contact which will coalesce under the action of surface tension alone. The free surface geometry development as well as its velocity during coalescence which are obtained from numerical computations are compared with an analogous experimental model. The viscosity in the numerical computations is then adjusted to bring into agreement of the experimental results with the calculations. The true liquid viscosity is the one which brings the experiment closest to the calculations. Results are presented for method validation experiments performed recently on board the NASA/KC-135 aircraft. The numerical solution for this validation case was produced using the Boundary Element Method. In these tests the viscosity of a highly viscous liquid, in this case glycerine at room temperature, was determined to high degree of accuracy using the liquid coalescence method. These experiments gave very encouraging results which will be discussed together with plans for implementing the method in a shuttle flight experiment.

Antar, Basil N.; Ethridge, Edwin; Maxwell, Daniel

1999-01-01

117

Coordinated Parallelizing Compiler Optimizations and High-Level Synthesis  

Microsoft Academic Search

We present a framework for high-level synthesis that enables the designer to explore the best choice of source level and low level parallelizing transformations for improved synthesis. Within this framework, we implemented a methodology that applies a set of parallelizing code transfor- mations, both at the source level and during scheduling. A designer can use these transformations to optimize high-level

SUMIT GUPTA; Alex Nicolau; Rajesh Gupta

2002-01-01

118

Gravity investigations  

SciTech Connect

A large density contrast exists between the Paleozoic rocks (including the rocks of Climax stock) and less dense, Tertiary volcanic rocks and alluvium. This density contrast ranges widely, and herein for interpretive purposes, is assumed to average 0.85 Mg/m{sup 3} (megagrams per cubic meter). The large density contrast makes the gravity method a useful tool with which to study the interface between these rock types. However, little or no density contrast is discernible between the sedimentary Paleozoic rocks that surround the Climax stock and the intrusive rocks of the stock itself. Therefore the gravity method can not be used to define the configuration of the stock. Gravity highs coincide with outcrops of the dense Paleozoic rocks, and gravity lows overlie less-dense Tertiary volcanic rocks and Quaternary alluvium. The positions of three major faults (Boundary, Yucca, and Butte faults) are defined by steep gravity gradients. West of the Climax stock, the Tippinip fault has juxtaposed Paleozoic rocks of similar density, and consequently, has no expression in the gravity data in that area. The gravity station spacing, across Oak Spring Butte, is not sufficient to adequately define any gravity expression of the Tippinip fault. 18 refs., 5 figs.

Healey, D.L. [Geological Survey, Denver, CO (USA)

1983-12-31

119

A simulation for gravity fine structure recovery from high-low GRAVSAT SST data  

NASA Technical Reports Server (NTRS)

Covariance error analysis techniques were applied to investigate estimation strategies for the high-low SST mission for accurate local recovery of gravitational fine structure, considering the aliasing effects of unsolved for parameters. Surface density blocks of 5 deg x 5 deg and 2 1/2 deg x 2 1/2 deg resolution were utilized to represent the high order geopotential with the drag-free GRAVSAT configured in a nearly circular polar orbit at 250 km. altitude. GEOPAUSE and geosynchronous satellites were considered as high relay spacecraft. It is demonstrated that knowledge of gravitational fine structure can be significantly improved at 5 deg x 5 deg resolution using SST data from a high-low configuration with reasonably accurate orbits for the low GRAVSAT. The gravity fine structure recoverability of the high-low SST mission is compared with the low-low configuration and shown to be superior.

Estes, R. H.; Lancaster, E. R.

1976-01-01

120

Gravity driven high throughput phase detecting cytometer based on quantitative interferometric microscopy  

NASA Astrophysics Data System (ADS)

Phase distribution detection of cells and tissues is concerned since it is an important auxiliary method for observing biological samples. High speed and large amount cell detection is needed for its high detecting efficiency. In this paper, we have proposed a simple large scale biological sample phase detection device called gravity driven high throughput phase detecting cytometer based on quantitative interferometric microscopy to obtain flowing red blood cells phase. The system could realize high throughput phase detecting and statistical analysis with high detecting speed and in real time. The statistical characteristics of red blood cells could be obtained which might be helpful for biological analysis and disease detection. We believe this method is a powerful tool to quantitatively measure the phase distribution of biological samples.

Xue, Liang; Wang, Shouyu; Yan, Keding; Sun, Nan; Ferraro, Pietro; Li, Zhenhua; Liu, Fei

2014-04-01

121

Satellite borne gravity gradiometer study  

NASA Technical Reports Server (NTRS)

Gravity gradiometry is recognized to be a very difficult instrumentation problem because extremely small differential acceleration levels have to be measured, 0.1 EU corresponds to an acceleration of 10 to the minus 11th power g at two points 1 meter apart. A feasibility model of a gravity gradiometer is being developed for airborne applications using four modified versions of the proven Model VII accelerometers mounted on a slowly rotating fixture. Gravity gradients are being measured to 1.07 EU in a vertical rotation axis orientation. Equally significant are the outstanding operational characteristics such as fast reaction time, low temperature coefficients and high degree of bias stability over long periods of time. The rotating accelerometer gravity gradiometer approach and its present status is discussed and it is the foundation for the orbital gravity gradiometer analyzed. The performance levels achieved in a 1 g environment of the earth and under relatively high seismic disturbances, lend the orbital gravity gradiometer a high confidence level of success.

Metzger, E.; Jircitano, A.; Affleck, C.

1976-01-01

122

Brane-world gravity  

E-print Network

The observable universe could be a 1+3-surface (the "brane") embedded in a 1+3+d-dimensional spacetime (the "bulk"), with standard-model particles and fields trapped on the brane while gravity is free to access the bulk. At least one of the d extra spatial dimensions could be very large relative to the Planck scale, which lowers the fundamental gravity scale, possibly even down to the electroweak (~ TeV) level. This revolutionary picture arises in the framework of recent developments in M theory. The 1+10-dimensional M theory encompasses the known 1+9-dimensional superstring theories, and is widely considered to be a promising potential route to quantum gravity. General relativity cannot describe gravity at high enough energies and must be replaced by a quantum gravity theory, picking up significant corrections as the fundamental energy scale is approached. At low energies, gravity is localized at the brane and general relativity is recovered, but at high energies gravity "leaks" into the bulk, behaving in a truly 1+3+d-dimensional way. This introduces significant changes to gravitational dynamics and perturbations, with interesting testable implications for high-energy astrophysics, black holes and cosmology. Brane-world models offer a phenomenological way to test some of the novel predictions and corrections to general relativity that are implied by M theory. This review discusses the geometry, dynamics and perturbations of simple brane-world models for cosmology and astrophysics, mainly focusing on warped 5-dimensional brane-worlds based on the Randall-Sundrum models.

Roy Maartens

2004-04-29

123

The new high voltage level up shifter for HVIC  

Microsoft Academic Search

A new high voltage level up shifter for high-voltage integrated circuits (HVIC) is presented that combines the optimized shape of a high doping concentration layer (N+ buried layer) and low doping isolation. In order to realize the high voltage level up shifter for HVIC, not only the P-doping level for isolation area but also the shape of N+ buried layer

J. J. Kim; M. H. Kim; S. L. Kim; C. K. Jeon; Y. S. Choi; H. S. Kang; C. S. Song

2002-01-01

124

Finite volume numerical scheme for high-resolution gravity field modelling and its parallel implementation  

NASA Astrophysics Data System (ADS)

The paper discusses a numerical solution of the geodetic boundary value problem (GBVP) by the finite volume method (FVM). The FVM is a numerical method where numerical flux is conserved from one discretization cell to its neighbour, so it's very appropriate for solving GBVP with the Neumann and the Dirichlet BCs. Our numerical scheme is developed for 3D computational domain above an ellipsoid. It is shown that a refinement of the discretization in height's direction leads to more precise numerical results. In order to achieve high-resolution numerical results, parallel implementations of algorithms using the MPI procedures were developed and computations on parallel computers were successfully performed. This basis includes the splitting of all arrays in meridian's direction, usage of an implementation of the Bi-CGSTAB non-stationary iterative solver instead of the standard SOR and an optimization of communications on parallel computers with the NUMA architecture. This gives us higher speed up in comparison to standard approaches and enables us to develop an efficient tool for high-resolution global or regional gravity field modelling in huge areas. Numerical experiments present global modelling with the resolution comparable with EGM2008 and detailed regional modelling in the Pacific Ocean with the resolution 2x2 arc min. Input gravity disturbances are generated from the DTU10-GRAV gravity field model and the disturbing potential is computed from the GOCE_DIR2 satellite geopotential model up to degree 240. Finally, the obtained disturbing potential is used to evaluate the geopotential on the DTU10 mean sea surface and the achieved mean dynamic topography is compared with the ECCO oceanographic model.

Fašková, Z.; Macák, M.; ?underlík, R.; Mikula, K.

2012-04-01

125

High-resolution Local Gravity Model of the South Pole of the Moon from GRAIL Extended Mission Data  

NASA Technical Reports Server (NTRS)

We estimated a high-resolution local gravity field model over the south pole of the Moon using data from the Gravity Recovery and Interior Laboratory's extended mission. Our solution consists of adjustments with respect to a global model expressed in spherical harmonics. The adjustments are expressed as gridded gravity anomalies with a resolution of 1/6deg by 1/6deg (equivalent to that of a degree and order 1080 model in spherical harmonics), covering a cap over the south pole with a radius of 40deg. The gravity anomalies have been estimated from a short-arc analysis using only Ka-band range-rate (KBRR) data over the area of interest. We apply a neighbor-smoothing constraint to our solution. Our local model removes striping present in the global model; it reduces the misfit to the KBRR data and improves correlations with topography to higher degrees than current global models.

Goossens, Sander Johannes; Sabaka, Terence J.; Nicholas, Joseph B.; Lemoine, Frank G.; Rowlands, David D.; Mazarico, Erwan; Neumann, Gregory A.; Smith, David E.; Zuber, Maria T.

2014-01-01

126

Goose Bay radar observations of earth-reflected atmospheric gravity waves in the high-latitude ionosphere  

SciTech Connect

An HF backscatter radar at Goose Bay, Labrador made it possible to observe irregularities in the distribution of ionospheric ionization at E and F region altitudes (100 - 600 km) in the high-latitude (65 - 85 deg Lambda) ionosphere. Recently it has been established that the passage of atmospheric gravity waves perturbs the ionosphere in ways that are readily detected in returns that reflect off the ionospheric layers. The particular strength of the technique lies in the nearly instantaneous measurement of gravity wave effects over large areas ( 1 million sq. km). With this information the propagation of gravity waves can be accurately modelled. Generally gravity waves are observed during daylight hours propagating away from the auroral electrojets. The propagation mode involves penetration of wave energy through the lower atmosphere and subsequent reflection by the earth's surface. The frequencies associated with the waves lie in the 0.4 - 0.6 mHz range and the wavelengths vary from 300 to 500 km. The excitation sources appear to lie in the vicinity of the high-latitude electrojets. In this paper we outline the analysis of gravity wave effects on HF propagation and present an example of a modelled gravity wave event.

Ruohoniemi, J.M.; Greenwald, R.A.; Baker, K.B.; Samson, J.C.

1990-05-03

127

ICONDENSATION: Unifying Low-Level and High-Level Tracking in a Stochastic Framework  

Microsoft Academic Search

. Tracking research has diverged into two camps; low-level approaches which are typically fast and robust but provide little fine-scale information, and high-level approaches which track complex deformations in high-dimensional spaces but must trade off speed against robustness. Real-time high-level systems perform poorly in clutter and initialisation for most high-level systems is either performed manually or by a separate module.

Michael Isard; Andrew Blake

1998-01-01

128

Ethanol Production from Extruded Thermoplastic Maize Meal by High Gravity Fermentation with Zymomonas mobilis  

PubMed Central

A comparative study of extruded and ground maize meals as raw materials for the production of regular (12°P) and high gravity (20°P) worts was devised. Extruded water solubility index (WSI) was higher (9.8 percentage units) and crude fat was lower (2.64 percentage units) compared to ground maize. Free-amino nitrogen compounds (FAN), pH, and glucose were evaluated in regular and high gravity worts produced from ground or extruded maize. Extrusion improved glucose content and ethanol yield. In 20°P mashes, extrusion is enhanced by 2.14% initial glucose compared with regular ground mashes. The 12°P and 20°P extruded treatments averaged 12.2% and 8.4% higher ethanol, respectively, compared to the uncooked counterpart. The 20°P worts fermented with Zymomonas mobilis produced 9.56% more ethanol than the 12°P counterpart. The results show that the combination of extrusion and fermentation of 20°P worts improved ethanol yield per kg flour until 20.93%. This pretreatment stimulates Z. mobilis fermentation efficiency. PMID:25530885

Peralta-Contreras, Mayeli; Aguilar-Zamarripa, Edna; Pérez-Carrillo, Esther; Escamilla-García, Erandi; Serna-Saldívar, Sergio Othon

2014-01-01

129

Ethanol Production from Extruded Thermoplastic Maize Meal by High Gravity Fermentation with Zymomonas mobilis.  

PubMed

A comparative study of extruded and ground maize meals as raw materials for the production of regular (12°P) and high gravity (20°P) worts was devised. Extruded water solubility index (WSI) was higher (9.8 percentage units) and crude fat was lower (2.64 percentage units) compared to ground maize. Free-amino nitrogen compounds (FAN), pH, and glucose were evaluated in regular and high gravity worts produced from ground or extruded maize. Extrusion improved glucose content and ethanol yield. In 20°P mashes, extrusion is enhanced by 2.14% initial glucose compared with regular ground mashes. The 12°P and 20°P extruded treatments averaged 12.2% and 8.4% higher ethanol, respectively, compared to the uncooked counterpart. The 20°P worts fermented with Zymomonas mobilis produced 9.56% more ethanol than the 12°P counterpart. The results show that the combination of extrusion and fermentation of 20°P worts improved ethanol yield per kg flour until 20.93%. This pretreatment stimulates Z. mobilis fermentation efficiency. PMID:25530885

Peralta-Contreras, Mayeli; Aguilar-Zamarripa, Edna; Pérez-Carrillo, Esther; Escamilla-García, Erandi; Serna-Saldívar, Sergio Othon

2014-01-01

130

40 CFR 227.30 - High-level radioactive waste.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2011-07-01 true High-level radioactive waste. 227.30 Section 227.30 Protection... Definitions § 227.30 High-level radioactive waste. High-level radioactive waste means the aqueous waste resulting...

2012-07-01

131

Gravity models of two-level collision of lithospheric plates in northeastern Asia  

NASA Astrophysics Data System (ADS)

Structural forms of emplacement of crustal and mantle rigid sheets in collision zones of lithospheric plates in northeastern Asia are analyzed using formalized gravity models reflecting the rheological properties of geological media. Splitting of the lithosphere of moving plates into crustal and mantle constituents is the main feature of collision zones, which is repeated in the structural units irrespective of their location, rank, and age. Formal signs of crustal sheet thrusting over convergent plate boundaries and subduction of the lithospheric mantle beneath these boundaries have been revealed. The deep boundaries and thickness of lithospheric plates and asthenospheric lenses have been traced. A similarity in the deep structure of collision zones of second-order marginal-sea buffer plates differing in age is displayed at the boundaries with the Eurasian, North American, and Pacific plates of the first order. Collision of oceanic crustal segments with the Mesozoic continental margin in the Sikhote-Alin is characterized, as well as collision of the oceanic lithosphere with the Kamchatka composite island arc. A spatiotemporal series of deep-seated Middle Mesozoic, Late Mesosoic, and Cenozoic collision tectonic units having similar structure is displayed in the transitional zone from the Asian continent to the Pacific plate.

Petrishchevsky, A. M.

2013-11-01

132

Perception of body weight and body mass at twice earth-gravity acceleration levels.  

PubMed

On Earth, when standing on two feet, we experience particular patterns of force and pressure on the soles of our feet. As we lift one foot and balance on the other, little or no increase in force or pressure is perceived on the sole of the stance foot even though the contact forces of support on that foot have doubled. The failure to perceive this increase is actually an illusion resulting from the operation of spatial constancy mechanisms serving to preserve feelings of near constant force and pressure on the support surface(s) of the body. On Earth, body weight and body mass are perceived as remaining constant regardless as to whether we are standing on two feet or one and whether we are carrying large objects. In the high force phase(2 g acceleration) of parabolic flight, body weight is perceived as doubling, and a great increase in force is perceived on the soles of our feet if we are standing. When shifting balance from two feet to one, an increase in force of approximately 0.5 mg is felt on the sole of the stance foot. The actual increase in force is 1.0 mg but perceptual compensation is only being made for a 0.5 mg increase such as would be characteristic of shifting balance on Earth; accordingly an additional 0.5 mg (1.0-0.5 mg) residue is perceived. These findings indicate that body weight is dependent on the magnitude of the gravitoinertial forces acting on the body. Variations in the contact forces supporting the body due to passive or active locomotion of the body or to objects that are being carried are monitored and disregarded in computing apparent body weight. When stepping up and down from a low platform during the high force phases of parabolic flight, aberrant motion of the body and the aircraft is experienced. These illusory motions result because the doubling of body weight in a 2 g force background alters the normal relationship between patterns of alpha and gamma activation of antigravity muscles, muscle spindle activity, and the movements of the body. Accordingly, sensory-motor control and perceptual and postural stability on Earth are dependent on an active calibration to a 1 g background force level. PMID:6697150

Lackner, J R; Graybiel, A

1984-03-01

133

Evaluation of an enhanced gravity-based fine-coal circuit for high-sulfur coal  

SciTech Connect

One of the main objectives of this study was to evaluate a fine-coal cleaning circuit using an enhanced gravity separator specifically for a high sulfur coal application. The evaluation not only included testing of individual unit operations used for fine-coal classification, cleaning and dewatering, but also included testing of the complete circuit simultaneously. At a scale of nearly 2 t/h, two alternative circuits were evaluated to clean a minus 0.6-mm coal stream utilizing a 150-mm-diameter classifying cyclone, a linear screen having a projected surface area of 0.5 m{sup 2}, an enhanced gravity separator having a bowl diameter of 250 mm and a screen-bowl centrifuge having a bowl diameter of 500 mm. The cleaning and dewatering components of both circuits were the same; however, one circuit used a classifying cyclone whereas the other used a linear screen as the classification device. An industrial size coal spiral was used to clean the 2- x 0.6-mm coal size fraction for each circuit to estimate the performance of a complete fine-coal circuit cleaning a minus 2-mm particle size coal stream. The 'linear screen + enhanced gravity separator + screen-bowl circuit' provided superior sulfur and ash-cleaning performance to the alternative circuit that used a classifying cyclone in place of the linear screen. Based on these test data, it was estimated that the use of the recommended circuit to treat 50 t/h of minus 2-mm size coal having feed ash and sulfur contents of 33.9% and 3.28%, respectively, may produce nearly 28.3 t/h of clean coal with product ash and sulfur contents of 9.15% and 1.61 %, respectively.

Mohanty, M.K.; Samal, A.R.; Palit, A. [South Illinois University, Carbondale, IL (United States). Dept. of Mining & Mineral Resources Engineering

2008-02-15

134

Statistics of high-level scene context  

PubMed Central

Context is critical for recognizing environments and for searching for objects within them: contextual associations have been shown to modulate reaction time and object recognition accuracy, as well as influence the distribution of eye movements and patterns of brain activations. However, we have not yet systematically quantified the relationships between objects and their scene environments. Here I seek to fill this gap by providing descriptive statistics of object-scene relationships. A total of 48, 167 objects were hand-labeled in 3499 scenes using the LabelMe tool (Russell et al., 2008). From these data, I computed a variety of descriptive statistics at three different levels of analysis: the ensemble statistics that describe the density and spatial distribution of unnamed “things” in the scene; the bag of words level where scenes are described by the list of objects contained within them; and the structural level where the spatial distribution and relationships between the objects are measured. The utility of each level of description for scene categorization was assessed through the use of linear classifiers, and the plausibility of each level for modeling human scene categorization is discussed. Of the three levels, ensemble statistics were found to be the most informative (per feature), and also best explained human patterns of categorization errors. Although a bag of words classifier had similar performance to human observers, it had a markedly different pattern of errors. However, certain objects are more useful than others, and ceiling classification performance could be achieved using only the 64 most informative objects. As object location tends not to vary as a function of category, structural information provided little additional information. Additionally, these data provide valuable information on natural scene redundancy that can be exploited for machine vision, and can help the visual cognition community to design experiments guided by statistics rather than intuition. PMID:24194723

Greene, Michelle R.

2013-01-01

135

Exploring Quantum Gravity with Very-High-Energy Gamma-Ray Instruments - Prospects and Limitations  

SciTech Connect

Some models for quantum gravity (QG) violate Lorentz invariance and predict an energy dependence of the speed of light, leading to a dispersion of high-energy gamma-ray signals that travel over cosmological distances. Limits on the dispersion from short-duration substructures observed in gamma-rays emitted by gamma-ray bursts (GRBs) at cosmological distances have provided interesting bounds on Lorentz invariance violation (LIV). Recent observations of unprecedentedly fast flares in the very-high energy gamma-ray emission of the active galactic nuclei (AGNs) Mkn 501 in 2005 and PKS 2155-304 in 2006 resulted in the most constraining limits on LIV from light-travel observations, approaching the Planck mass scale, at which QG effects are assumed to become important. I review the current status of LIV searches using GRBs and AGN flare events, and discuss limitations of light-travel time analyses and prospects for future instruments in the gamma-ray domain.

Wagner, Robert [Max-Planck-Institut fuer Physik, D-80805 Muenchen (Germany)

2009-04-08

136

High order level contour reconstruction method  

Microsoft Academic Search

Complex interfacial physics arising from geometric curvature associated with surface tension as well as phase transformation\\u000a make it a formidable task to design an accurate, reliable, and yet simple method for direct computation of multiphase flows.\\u000a Hybrid methods mixing conventional, Volume-of-Fluid, Level Set, Phase Field, and Front Tracking methods have recently become\\u000a popular in an attempt to overcome the shortcomings

Seungwon Shin; Damir Juric

2007-01-01

137

Local gravity disturbance estimation from multiple-high-single-low satellite-to-satellite tracking  

NASA Technical Reports Server (NTRS)

The idea of satellite-to-satellite tracking in the high-low mode has received renewed attention in light of the uncertain future of NASA's proposed low-low mission, Geopotential Research Mission (GRM). The principal disadvantage with a high-low system is the increased time interval required to obtain global coverage since the intersatellite visibility is often obscured by Earth. The U.S. Air Force has begun to investigate high-low satellite-to-satellite tracking between the Global Positioning System (GPS) of satellites (high component) and NASA's Space Transportation System (STS), the shuttle (low component). Because the GPS satellites form, or will form, a constellation enabling continuous three-dimensional tracking of a low-altitude orbiter, there will be no data gaps due to lack of intervisibility. Furthermore, all three components of the gravitation vector are estimable at altitude, a given grid of which gives a stronger estimate of gravity on Earth's surface than a similar grid of line-of-sight gravitation components. The proposed Air Force mission is STAGE (Shuttle-GPS Tracking for Anomalous Gravitation Estimation) and is designed for local gravity field determinations since the shuttle will likely not achieve polar orbits. The motivation for STAGE was the feasibility to obtain reasonable accuracies with absolutely minimal cost. Instead of simulating drag-free orbits, STAGE uses direct measurements of the nongravitational forces obtained by an inertial package onboard the shuttle. The sort of accuracies that would be achievable from STAGE vis-a-vis other satellite tracking missions such as GRM and European Space Agency's POPSAT-GRM are analyzed.

Jekeli, Christopher

1989-01-01

138

Cineradiographic Analysis of Mouse Postural Response to Alteration of Gravity and Jerk (Gravity Deceleration Rate)  

PubMed Central

The ability to maintain the body relative to the external environment is important for adaptation to altered gravity. However, the physiological limits for adaptation or the disruption of body orientation are not known. In this study, we analyzed postural changes in mice upon exposure to various low gravities. Male C57BL6/J mice (n = 6) were exposed to various gravity-deceleration conditions by customized parabolic flight-maneuvers targeting the partial-gravity levels of 0.60, 0.30, 0.15 and ? g (<0.001 g). Video recordings of postural responses were analyzed frame-by-frame by high-definition cineradiography and with exact instantaneous values of gravity and jerk. As a result, the coordinated extension of the neck, spine and hindlimbs was observed during the initial phase of gravity deceleration. Joint angles widened to 120%–200% of the reference g level, and the magnitude of the thoracic-curvature stretching was correlated with gravity and jerk, i.e., the gravity deceleration rate. A certain range of jerk facilitated mouse skeletal stretching efficiently, and a jerk of ?0.3~?0.4 j (g/s) induced the maximum extension of the thoracic-curvature. The postural response of animals to low gravity may undergo differential regulation by gravity and jerk. PMID:25370191

Hasegawa, Katsuya; de Campos, Priscila S.; Zeredo, Jorge L.; Kumei, Yasuhiro

2014-01-01

139

Machine Learning Methods for High Level Cyber Situation Awareness  

E-print Network

Machine Learning Methods for High Level Cyber Situation Awareness Thomas G. Dietterich, Xinlong Bao, Victoria Keiser and Jianqiang Shen 1 Introduction Cyber situation awareness needs to operate at many levels. The chapter concludes with a discussion of future directions for high level cyber situation awareness. 2

140

GOCE long-wavelength gravity field recovery from high-low satellite-to-satellite-tracking using the acceleration approach  

NASA Astrophysics Data System (ADS)

The restricted sensitivity of the GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometer instrument requires satellite gravity gradiometry to be supplemented by orbit analysis in order to resolve long-wavelength features of the geopotential. In this context, the energy conservation method gained particular interest to exploit GPS-based satellite-to-satellite tracking (SST) information. This method has been adopted within official ESA products. On the other hand, various investigations showed the energy conservation principle to be a sub-optimal choice. For this reason, we propose to estimate the low-frequency part of the gravity field by the acceleration approach, which proved to be an efficient and accurate tool in high-low-SST data analysis of former satellite data. This approach balances the gravitational vector with satellite accelerations by means of Newton's law of motion, and hence is characterized by (second-order) numerical differentiation of the kinematic orbit. However, the application of this method to GOCE-SST data, given with a 1s-sampling, showed that serious problems arise due to strong noise amplification of high frequency noise. In order to mitigate this problem, tailored processing strategies with regard to low-pass filtering, variance-covariance information handling, and robust parameter estimation have been adopted. By comparison of our GIWF (Geodetic Institute (GI), Space Research Institute (Institut für Weltraumforschung, IWF)) solutions and the official GOCE models with a state-of-the-art gravity field solution derived from GRACE (Gravity Recovery And Climate Experiment), we conclude that the acceleration approach is better suited for GOCE-only gravity field determination as opposed to the energy conservation method. Comparisons with solutions from other algorithms, e.g. the variational approach, show that the acceleration approach is able to estimate gravity fields of similar quality.

Reubelt, T.; Baur, O.; Weigelt, M.; Roth, M.; Sneeuw, N.

2012-04-01

141

Complete Bouguer gravity map of the Nevada Test Site and vicinity, Nevada  

SciTech Connect

About 15,000 gravity stations were used to create the gravity map. Gravity studies at the Nevada Test Site were undertaken to help locate geologically favorable areas for underground nuclear tests and to help characterize potential high-level nuclear waste storage sites. 48 refs. (TEM)

Healey, D.L.; Harris, R.N.; Ponce, D.A.; Oliver, H.W.

1987-12-31

142

Global gravity field modeling based on GOCE and complementary gravity data  

NASA Astrophysics Data System (ADS)

A combined high-resolution global gravity field model up to degree/order (d/o) 720, including error estimates in terms of a full variance-covariance matrix, is determined from GOCE (Gravity field and steady-state Ocean Circulation Explorer) and complementary gravity field data. GOCE observations, highly accurate in the low to medium wavelength part (?d/o 40-220), are supplemented by GRACE (Gravity Recovery and Climate Experiment) with high accuracy in the low wavelength part (?d/o 2-150), and altimetric and terrestrial gravity field observations to enhance the spectral resolution of the combined gravity field model. The theory of combining different data sets by least-squares techniques, applying optimum weighting strategies, is illustrated. Full normal equation systems are used to enable stochastic modeling of all individual observations. High performance computing techniques are applied in order to handle normal equations of enormous size (about 2 TB). The quality of the resulting gravity field solution is analyzed by comparisons with independent gravity field models and GPS/leveling observations, and also in the frame of the computation of a mean dynamic topography. The validation shows that the new combined model TUM2013C achieves the quality level of established high-resolution models. Compared to EGM2008, the improvements due to the inclusion of GOCE are clearly visible.

Fecher, Thomas; Pail, Roland; Gruber, Thomas

2015-03-01

143

High Energy Astrophysics Tests of Lorentz Invariance and Quantum Gravity Models  

NASA Technical Reports Server (NTRS)

High-energy astrophysics observations provide the best possibilities to detect a very small violation of Lorentz invariance such as may be related to the structure of space-time near the Planck scale of approximately 10-35 m. I will discuss here the possible signatures of Lorentz invariance violation (LIV) from observations of the spectra, polarization, and timing of gamma-rays from active galactic nuclei and gamma-ray bursts. Other sensitive tests are provided by observations ofthe spectra of ultrahigh energy cosmic rays and neutrinos. Using the latest data from the Pierre Auger Observatory one can already derive an upper limit of 4.5 x 10(exp -23) to the amount of LIV at a proton Lorentz factor of -2 x 10(exp 11). This result has fundamental implications for quantum gravity models. I will also discuss the possibilities of using more sensitive space based detection techniques to improve searches for LIV in the future.

Stecker, Floyd W.

2011-01-01

144

Simultaneous dewatering and reconstitution in a high-gravity solid-bowl centrifuge  

SciTech Connect

The Pittsburgh Energy Technology Center has developed a dewatering and reconstitution process in which bitumen emulsion is added to a fine clean coal slurry ahead of the dewatering device. The process simultaneously improves dewatering efficiency and reduces dustiness of the fine coal product during subsequent handling. This paper describes the test results from dewatering and reconstitution of fine coal in a 500 lb. per hour continuous bench scale high-gravity solid-bowl centrifuge in PETC`s Coal Preparation Process Research Facility. Test results will be evaluated in terms of type and dosage of emulsion, product moisture and strength, and product handling and dust reduction efficiency. A preliminary cost analysis will also be included.

Wen, W.W.; Gray, M.L.; Killmeyer, R.P.; Finseth, D.H. [USDOE Pittsburgh Energy Technology Center, PA (United States)

1994-12-31

145

Fundamentals of gravity level dependent two-phase flow and heat transfer-A tutorial  

Microsoft Academic Search

Multiphase flow, the simultaneous flow of the different phases (states of matter) gas, liquid and solid, strongly depends on the level and direction of gravitation, since these influence the spatial distribution of the phases, having different densities. Many investigations concern behavior of liquid-solid flows (e.g. in mixing, crystal growing, or materials processing) or gas-solid flows (e.g. in cyclones or combustion

A. A. M. Delil

2001-01-01

146

Fundamentals of gravity level dependent two-phase flow and heat transfer—A tutorial  

Microsoft Academic Search

Multiphase flow, the simultaneous flow of the different phases (states of matter) gas, liquid and solid, strongly depends on the level and direction of gravitation, since these influence the spatial distribution of the phases, having different densities. Many investigations concern behavior of liquid-solid flows (e.g. in mixing, crystal growing, or materials processing) or gas-solid flows (e.g. in cyclones or combustion

A. A. M. Delil

2001-01-01

147

Optical Mass Gauging System for Measuring Liquid Levels in a Reduced Gravity Environment  

NASA Technical Reports Server (NTRS)

A compact and rugged fiber-coupled liquid volume sensor designed for flight on a sounding rocket platform is presented. The sensor consists of a Mach-Zehnder interferometer capable of measuring the amount of liquid contained in a tank under any gravitational conditions, including a microgravity environment, by detecting small changes in the index of refraction of the gas contained within a sensing region. By monitoring changes in the interference fringe pattern as the system undergoes a small compression provided by a piston, the ullage volume of a tank can be directly measured allowing for a determination of the liquid volume. To demonstrate the technique, data are acquired using two tanks containing different volumes of liquid, which are representative of the levels of liquid in a tank at different time periods during a mission. The two tanks are independently exposed to the measurement apparatus, allowing for a determination of the liquid level in each. In a controlled, laboratory test of the unit, the system demonstrated a capability of measuring a liquid level in an individual tank of 10.53 mL with a 2% error. The overall random uncertainty for the flight system is higher than that one test, at +/- 1.5 mL.

Sullenberger, Ryan M.; Munoz, Wesley M.; Lyon, Matt P.; Vogel, Kenny; Yalin, Azer P.; Korman, Valentin; Polzin, Kurt A.

2010-01-01

148

Physics of Artificial Gravity  

NASA Technical Reports Server (NTRS)

This chapter discusses potential technologies for achieving artificial gravity in a space vehicle. We begin with a series of definitions and a general description of the rotational dynamics behind the forces ultimately exerted on the human body during centrifugation, such as gravity level, gravity gradient, and Coriolis force. Human factors considerations and comfort limits associated with a rotating environment are then discussed. Finally, engineering options for designing space vehicles with artificial gravity are presented.

Bukley, Angie; Paloski, William; Clement, Gilles

2006-01-01

149

Bilateral medial patellofemoral ligament reconstruction in high-level athletes.  

PubMed

This report presents two cases of high-level athletes with bilateral patellar dislocations who were able to return to their preinjury level of activity after bilateral medial patellofemoral ligament (MPFL) reconstruction, without any major complications. Patient 1 was a 19-year-old male volleyball player for a top-level college volleyball team, and patient 2 was a 24-year-old woman who was a member of a national-level adult softball team. MPFL reconstruction could be an effective treatment for bilateral patellar dislocation in high-level athletes. Level of evidence V. PMID:24744173

Kuroda, Yuichi; Matsushita, Takehiko; Matsumoto, Tomoyuki; Kawakami, Yohei; Kurosaka, Masahiro; Kuroda, Ryosuke

2014-10-01

150

DOE HIGH-LEVEL VITRIFIED WASTE DOSE CALCULATION  

SciTech Connect

The purpose of this engineering calculation is to provide the radiological dose at 5,000 meters from the surface facilities of the Monitored Geologic Repository (MGR) resulting from a drop of one High-Level Waste (HLW) canister containing vitrified high-level waste glass during handling operations in the Waste Handling Building (WHB). High-level vitrified wastes from Savannah River Site (SRS), Hanford Works, West Valley, New York, and Idaho National Engineering and Environmental Laboratory (INEEL) are evaluated. This calculation will provide input data for future safety analyses for handling of Department of Energy (DOE) high-level waste in the MGR.

J.A. Ziegler

1999-08-26

151

Cracking Analysis of High Concrete Gravity Dams Under Floodwater and Seismic Effects  

Microsoft Academic Search

As economic develops, energy demand is also increasing. The development of hydroelectric energy has become one of the important measures to deal with energy crisis. In order to develop hydropower, many high concrete dams are being built or about to build in China. These dams are often operating at high water level and in high seismic intensity region. Accident due

Jia Chao; Li Yafei; Ren Qingwen

2010-01-01

152

High degree gravitational sensitivity from Mars orbiters for the GMM-1 gravity model  

NASA Technical Reports Server (NTRS)

Orbital sensitivity of the gravity field for high degree terms (greater than 30) is analyzed on satellites employed in a Goddard Mars Model GMM-1, complete in spherical harmonics through degree and order 50. The model is obtained from S-band Doppler data on Mariner 9 (M9), Viking Orbiter 1 (VO1), and Viking Orbiter 2 (VO2) spacecraft, which were tracked by the NASA Deep Space Network on seven different highly eccentric orbits. The main sensitivity of the high degree terms is obtained from the VO1 and VO2 low orbits (300 km periapsis altitude), where significant spectral sensitivity is seen for all degrees out through degree 50. The velocity perturbations show a dominant effect at periapsis and significant effects out beyond the semi-latus rectum covering over 180 degrees of the orbital groundtrack for the low altitude orbits. Because of the wideband of periapsis motion covering nearly 180 degrees in w and +39 degrees in latitude coverage, the VO1 300 km periapsis altitude orbit with inclination of 39 degrees gave the dominant sensitivity in the GMM-1 solution for the high degree terms. Although the VO2 low periapsis orbit has a smaller band of periapsis mapping coverage, it strongly complements the VO1 orbit sensitivity for the GMM-1 solution with Doppler tracking coverage over a different inclination of 80 degrees.

Lerch, F. J.; Smith, D. E.; Chan, J. C.; Patel, G. B.; Chinn, D. S.

1994-01-01

153

The energetics and mechanics of level and gradient skipping: Preliminary results for a potential gait of choice in low gravity environments.  

NASA Astrophysics Data System (ADS)

Walking and running in low gravity cannot be used at useful speeds, while 'skipping', a gait displayed by kids and spontaneously adopted by astronauts of Apollo missions, proved to have the potential to become the gait of choice in that condition. In this paper the previous biomechanical and metabolic analysis of level skipping is extended to positive and negative gradients, in normal gravity. The results confirm at all gradients the higher (average) ground reaction force during the contact phase, with respect to running at the same speed, which would allow confidently facing the Lunar surface where the dust and regoliths affect, in addition to a lower gravity, the locomotion dynamics. Metabolic data, other gait variables related to the mechanical work done and the locomotor/respiratory coupling have also been investigated.

Minetti, Alberto E.; Pavei, Gaspare; Biancardi, Carlo M.

2012-12-01

154

Aeromagnetic study of the midcontinent gravity high of central United States  

USGS Publications Warehouse

A composite map of detailed aeromagnetic surveys over the midcontinent gravity high provides coverage of the 600-mi-long buried belt of mafic rocks of the Keweenawan Series from their outcrop localities in Minnesota and Wisconsin through Iowa and Nebraska. A map of the subsurface extent of the mafic rocks, based on the intricate magnetic patterns, shows that the rocks form a long, semicontinuous block, averaging 40 mi wide and consisting mainly of a sequence of layered flows. This sequence is probably fault-bounded and has been tilted up along the margins, where the linearity of the anomalies indicates steeper dips. The associated clastic rocks, indicated by a smoother magnetic pattern, occur in basins along both sides of the mafic belt and in grabens and a series of axial basins on the upper surface of the block. The well-defined outliers of flows marginal to the main block and the truncation of some of the outermost flow units along a diagonal boundary striking at an angle to them suggest that the present boundaries of the block are postdepositional structural features. The basins and the edges of the block appear to have controlled later, largely vertical movement in the overlying Paleozoic and younger sedimentary cover. Calculated models based on coincident magnetic and detailed gravity profiles along typical cross sections of the midcontinent gravity high show that the block of mafic rocks is steep-sided and as much as several miles thick. The free-air gravity anomaly, which consists of a large positive maximum flanked by minima, averages very close to zero, indicating that this major crustal feature is regionally compensated, although locally each of its components shows a large departure from equilibrium. Remanent magnetization is a primary factor in the interpretation of the magnetic data. Magnetic property studies of Keweenawan mafic rocks in the Lake Superior region show that remanent magnetization may be five times the magnetization induced by the present Earth's field and differs from it radically in direction. This magnetization was acquired before the flows were tilted into their present positions. A computed magnetic profile shows that a trough of flows with such a magnetization and inward-dipping limbs can account for the observed persistent lows along the western edge of the block, the relatively low magnetic values along the axis of the block, and the large positive anomaly along the eastern side of the block. Flows as much as 1 mi thick near the base of the sequence have a remanent magnetization with a nearly opposite polarity. This reverse polarity has been measured on both sides of Lake Superior and is probably also present farther south, particularly in Iowa where the outer units of the block in an area north of Des Moines give rise to a prominent magnetic low. The axis of this long belt of Keweenawan mafic rocks cuts discordantly through the prevailing east-west-trending fabric of the older Precambrian terrane from southern Kansas to Lake Superior. This belt has several major left-lateral offsets, one of which produces a complete hiatus in the vicinity of the 40th parallel where an east-west transcontinental rift or fracture zone has been proposed. The axial basins of clastic rocks are outlined by linear magnetic anomalies and show a concordant relation to the structure of the mafic flows. These basins are oriented at an angle to the main axis, suggesting that the entire feature originated as a major rift composed of a series of short, linear, en echelon segments with offsets similar to the transform faults characterizing the present mid-ocean rift system. This midcontinent rift may well have been part of a Keweenawan global rift system with initial offsets consisting of transform faults along pre-existing fractures, but apparently it never fully developed laterally into an ocean basin, and the upwelling mafic material was localized along a relatively narrow belt.

King, Elizabeth R.; Zietz, Isidore

1971-01-01

155

Aeromagrnetic study of the midcontinent gravity high of central United States  

USGS Publications Warehouse

A composite map of detailed aeromagnetic surveys over the midcontinent gravity high provides coverage of the 600-mi-long buried belt of mafic rocks of the Keweenawan Series from their outcrop localities in Minnesota and Wisconsin through Iowa and Nebraska. A map of the subsurface extent of the mafic rocks, based on the intricate magnetic patterns, shows that the rocks form a long, semicontinuous block, averaging 40 mi wide and consisting mainly of a sequence of layered flows. This sequence is probably fault-bounded and has been tilted up along the margins, where the linearity of the anomalies indicates steeper dips. The associated clastic rocks, indicated by a smoother magnetic pattern, occur in basins along both sides of the mafic belt and in grabens and a series of axial basins on the upper surface of the block. The well-defined outliers of flows marginal to the main block and the truncation of some of the outermost flow units along a diagonal boundary striking at an angle to them suggest that the present boundaries of the block are postdepositional structural features. The basins and the edges of the block appear to have controlled later, largely vertical movement in the overlying Paleozoic and younger sedimentary cover. Calculated models based on coincident magnetic and detailed gravity profiles along typical cross sections of the midcontinent gravity high show that the block of mafic rocks is steep-sided and as much as several miles thick. The free-air gravity anomaly, which consists of a large positive maximum flanked by minima, averages very close to zero, indicating that this major crustal feature is regionally compensated, although locally each of its components shows a large departure from equilibrium. Remanent magnetization is a primary factor in the interpretation of the magnetic data. Magnetic property studies of Keweenawan mafic rocks in the Lake Superior region show that remanent magnetization may be five times the magnetization induced by the present Earth's field and differs from it radically in direction. This magnetization was acquired before the flows were tilted into their present positions. A computed magnetic profile shows that a trough of flows with such a magnetization and inward-dipping limbs can account for the observed persistent lows along the western edge of the block, the relatively low magnetic values along the axis of the block, and the large positive anomaly along the eastern side of the block. Flows as much as 1 mi thick near the base of the sequence have a remanent magnetization with a nearly opposite polarity. This reverse polarity has been measured on both sides of Lake Superior and is probably also present farther south, particularly in Iowa where the outer units of the block in an area north of Des Moines give rise to a prominent magnetic low. The axis of this long belt of Keweenawan mafic rocks cuts discordantly through the prevailing east-west-trending fabric of the older Precambrian terrane from southern Kansas to Lake Superior. This belt has several major left-lateral offsets, one of which produces a complete hiatus in the vicinity of the 40th parallel where an east-west transcontinental rift or fracture zone has been proposed. The axial basins of clastic rocks are outlined by linear magnetic anomalies and show a concordant relation to the structure of the mafic flows. These basins are oriented at an angle to the main axis, suggesting that the entire feature originated as a major rift composed of a series of short, linear, en echelon segments with offsets similar to the transform faults characterizing the present mid-ocean rift system. This midcontinent rift may well have been part of a Keweenawan global rift system with initial offsets consisting of transform faults along pre-existing fractures, but apparently it never fully developed laterally into an ocean basin, and the upwelling mafic material was localized along a relatively narrow belt.

King, Elizabeth R.; Zietz, Isidore

1971-01-01

156

Gravity waves simulated by high-resolution Whole Atmosphere Community Climate Model  

NASA Astrophysics Data System (ADS)

For the first time a mesoscale-resolving whole atmosphere general circulation model has been developed, using the National Center for Atmospheric Research Whole Atmosphere Community Climate Model with ˜0.25° horizontal resolution and 0.1 scale height vertical resolution above the middle stratosphere (higher resolution below). This is made possible by the high accuracy and high scalability of the spectral element dynamical core from the High-Order Method Modeling Environment. For the simulated January-February period, the latitude-height structure and the magnitudes of the temperature variance compare well with those deduced from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) observations. The simulation reveals the increasing dominance of gravity waves (GWs) at higher altitudes through both the height dependence of the kinetic energy spectra, which display a steeper slope (˜-3) in the stratosphere and an increasingly shallower slope above, and the increasing spatial extent of GWs (including a planetary-scale extent of a concentric GW excited by a tropical cyclone) at higher altitudes. GW impacts on the large-scale flow are evaluated in terms of zonal mean zonal wind and tides: with no GW drag parameterized in the simulations, forcing by resolved GWs does reverse the summer mesospheric wind, albeit at an altitude higher than climatology, and only slows down the winter mesospheric wind without closing it. The hemispheric structures and magnitudes of diurnal and semidiurnal migrating tides compare favorably with observations.

Liu, H.-L.; McInerney, J. M.; Santos, S.; Lauritzen, P. H.; Taylor, M. A.; Pedatella, N. M.

2014-12-01

157

Nutritional intake and fitness levels of high school cheerleaders  

Microsoft Academic Search

Studies of female sports such as figure skating, dance and gymnastics, especially at the elite levels, have raised serious concerns related to overtraining and disordered eating. However, very little is known about the nutrition and fitness levels of cheerleaders. The present study was designed to identify the fitness levels of female high school cheerleaders, their nutritional intake, and potential eating

Nicole Ferrari

2005-01-01

158

Physical Activity Levels in Portuguese High School Physical Education  

ERIC Educational Resources Information Center

The main aim of this study was to evaluate the physical activity (PA) levels of high school Portuguese students during physical education (PE) and investigate the association of PA levels with students' goal orientation and intrinsic motivation. Forty-six students from three high schools participated. Heart rate telemetry and pedometry were used…

Marmeleira, Jose Francisco Filipe; Aldeias, Nuno Micael Carrasqueira; da Graca, Pedro Miguel dos Santos Medeira

2012-01-01

159

Generating Code for HighLevel Operations through Code Composition  

E-print Network

is attractive if the source language contains complex, powerful constructs, like the distributed array Catacomb, my implementation of a composition system, which integrates with a high­level com­ pilerGenerating Code for High­Level Operations through Code Composition James M. Stichnoth August 1997

Shewchuk, Jonathan

160

Generating Code for High-Level Operations through Code Composition  

E-print Network

is attractive if the source language contains complex, powerful constructs, like the distributed array Catacomb, my implementation of a composition system, which integrates with a high-level com- pilerGenerating Code for High-Level Operations through Code Composition James M. Stichnoth August 1997

161

Dominance, plasma testosterone levels, and testis size in house mice artificially selected for high activity levels  

E-print Network

Dominance, plasma testosterone levels, and testis size in house mice artificially selected for high replicate lines selectively bred for high voluntary wheel-running behavior were compared with four random-bred control lines with respect to dominance, testis size, and plasma testosterone level. Behavior was measured

Garland Jr., Theodore

162

High precision gravity analysis and hydrological modeling from the Lunar Laser Ranging Observatory at Apache Point, New Mexico  

NASA Astrophysics Data System (ADS)

The NASA-supported Lunar Laser Ranging project (LLR) is located at Apache Point, New Mexico, which strives to precisely measure the orbital distance between the Earth and the Moon in an accuracy of a few millimeters. To archive this objective, LLR project requires precise data on local ground deformation, which is difficult to measure directly. However, the high precision gravity data is the reflection of vertical ground deformation of the Earth, therefore the gravity data is able to contribute to the LLR project. Gravity time series is affected by Earth tides, atmospheric pressure, polar motion, and the most critical effect, local hydrology. In order to isolate pure geodetic variation, these effects must be removed from the data. Thus, the goal of this research is to create models of above effects, especially local hydrology model, in order to isolate the vertical deformation signal. The Earth tides, atmospheric pressure and polar motion effects have been modeled and subtracted from gravity data (2009~2012). The local hydrological model has been created based on the in-situ data, which are rainfall, snowfall and temperature. The correlation coefficient and RMS misfit between the hydrological model and gravity residual (2010~2012) is 0.92 and 1.26 microGal. The instrument drift corrections in 2009 have been reanalyzed after comparing with some global hydrological models. The gravity residual from new corrections showed a correlation coefficient of 0.76 and RMS misfit of 1.25 microGal. The isolated deformation signal was obtained after we subtracted the hydrological effects, and the results can be used for further modeling.

Liang, Jiahao

163

Changes in water levels and storage in the High Plains Aquifer, predevelopment to 2009  

USGS Publications Warehouse

The High Plains aquifer underlies 111.8 million acres (175,000 square miles) in parts of eight States - Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. The area overlying the High Plains aquifer is one of the primary agricultural regions in the Nation. Water-level declines began in parts of the High Plains aquifer soon after the onset of substantial irrigation with groundwater from the aquifer (about 1950 and termed "predevelopment" in this fact sheet). By 1980, water levels in the High Plains aquifer in parts of Texas, Oklahoma, and southwestern Kansas had declined more than 100 feet (ft) (Luckey and others, 1981). In 1987, in response to declining water levels, Congress directed the U.S. Geological Survey (USGS), in collaboration with numerous Federal, State, and local water-resources entities, to assess and track water-level changes in the aquifer. This fact sheet summarizes changes in water levels and drainable water in storage in the High Plains aquifer from predevelopment to 2009. Drainable water in storage is the fraction of water in the aquifer that will drain by gravity and can be withdrawn by wells. The remaining water in the aquifer is held to the aquifer material by capillary forces and generally cannot be withdrawn by wells. Drainable water in storage is termed "water in storage" in this report. A companion USGS report presents more detailed and technical information about water-level and storage changes in the High Plains aquifer during this period (McGuire, 2011).

McGuire, V.L.

2011-01-01

164

On the influence of the ground track on the gravity field recovery from high–low satellite-to-satellite tracking missions: CHAMP monthly gravity field recovery using the energy balance approach revisited  

Microsoft Academic Search

In this paper, the influence of the ground track coverage on the quality of a monthly gravity field solution is investigated\\u000a for the scenario of a high–low satellite- to-satellite tracking mission. Data from the CHAllenging Minisatellite Payload (champ) mission collected in the period April 2002 to February 2004 has been used to recover the gravity field to degree and order

Matthias Weigelt; Michael G. Sideris; Nico Sneeuw

2009-01-01

165

Reference commercial high-level waste glass and canister definition.  

SciTech Connect

This report presents technical data and performance characteristics of a high-level waste glass and canister intended for use in the design of a complete waste encapsulation package suitable for disposal in a geologic repository. The borosilicate glass contained in the stainless steel canister represents the probable type of high-level waste product that will be produced in a commercial nuclear-fuel reprocessing plant. Development history is summarized for high-level liquid waste compositions, waste glass composition and characteristics, and canister design. The decay histories of the fission products and actinides (plus daughters) calculated by the ORIGEN-II code are presented.

Slate, S.C.; Ross, W.A.; Partain, W.L.

1981-09-01

166

Reference commercial high-level waste glass and canister definition  

NASA Astrophysics Data System (ADS)

Technical data and performance characteristics of a high level waste glass and canister intended for use in the design of a complete waste encapsulation package suitable for disposal in a geologic repository are presented. The borosilicate glass contained in the stainless steel canister represents the probable type of high level waste product that is produced in a commercial nuclear-fuel reprocessing plant. Development history is summarized for high level liquid waste compositions, waste glass composition and characteristics, and canister design. The decay histories of the fission products and actinides (plus daughters) calculated by the ORIGEN-II code are presented.

Slate, S. C.; Ross, W. A.; Partain, W. L.

1981-09-01

167

Investigating why recycling gravity harvested algae increases harvestability and productivity in high rate algal ponds.  

PubMed

It has previously been shown that recycling gravity harvested algae promotes Pediastrum boryanum dominance and improves harvestability and biomass production in pilot-scale High Rate Algal Ponds (HRAPs) treating domestic wastewater. In order to confirm the reproducibility of these findings and investigate the mechanisms responsible, this study utilized twelve 20 L outdoor HRAP mesocosms operated with and without algal recycling. It then compared the recycling of separated solid and liquid components of the harvested biomass against un-separated biomass. The work confirmed that algal recycling promoted P. boryanum dominance, improved 1 h-settleability by >20% and increased biomass productivity by >25% compared with controls that had no recycling. With regard to the improved harvestability, of particular interest was that recycling the liquid fraction alone caused a similar improvement in settleability as recycling the solid fraction. This may be due to the presence of extracellular polymeric substances in the liquid fraction. While there are many possible mechanisms that could account for the increased productivity with algal recycling, all but two were systematically eliminated: (i) the mean cell residence time was extended thereby increasing the algal concentration and more fully utilizing the incident sunlight and, (ii) the relative proportions of algal growth stages (which have different specific growth rates) was changed, resulting in a net increase in the overall growth rate of the culture. PMID:23866138

Park, J B K; Craggs, R J; Shilton, A N

2013-09-15

168

Accelerated carbonation of steelmaking slags in a high-gravity rotating packed bed.  

PubMed

Carbon dioxide (CO(2)) sequestration using the accelerated carbonation of basic oxygen furnace (BOF) slag in a high-gravity rotating packed bed (RPB) under various operational conditions was investigated. The effects of reaction time, reaction temperature, rotation speed and slurry flow rate on the CO(2) sequestration process were evaluated. The samples of reacted slurry were analyzed quantitatively using thermogravimetric analysis (TGA) and atomic absorption spectrometry (AAS) and qualitatively using X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX), and transmission electron microscopy (TEM). The sequestration experiments were performed at a liquid-to-solid ratio of 20:1 with a flow rate of 2.5 L min(-1) of a pure CO(2) stream under atmospheric temperature and pressure. The results show that a maximum conversion of BOF slag was 93.5% at a reaction time of 30 min and a rotation speed of 750 rpm at 65°C. The experimental data were utilized to determine the rate-limiting mechanism based on the shrinking core model (SCM), which was validated by the observations of SEM and TEM. Accelerated carbonation in a RPB was confirmed to be a viable method due to its higher mass-transfer rate. PMID:22633879

Chang, E-E; Pan, Shu-Yuan; Chen, Yi-Hung; Tan, Chung-Sung; Chiang, Pen-Chi

2012-08-15

169

High Energy Astrophysics Tests of Lorentz Invariance and Quantum Gravity Models  

NASA Technical Reports Server (NTRS)

High energy astrophysics observations provide the best possibilities to detect a very small violation of Lorentz invariance such as may be related to the structure of space-time near the Planck scale of approx.10(exp -35) m. I will discuss the possible signatures of Lorentz invariance violation (LIV) that can be manifested by observing of the spectra, polarization, and timing of gamma-rays from active galactic nuclei and gamma-ray bursts. Other sensitive tests are provided by observations of the spectra of ultrahigh energy cosmic rays and neutrinos. Using the latest data from the Pierre Auger Observatory one can already derive an upper limit of 4.5 x 10(exp -23) on the fraction of LIV at a Lorentz factor of approx. 2 x 10(exp 11). This result has fundamental implications for quantum gravity models. I will also discuss the possibilities of using more sensitive space-based detection techniques to improve searches for LIV in the future. I will also discuss how the LIV formalism casts doubt on the OPERA superluminal neutrino claim.

Stecker, Floyd W.

2012-01-01

170

High Energy Astrophysics Tests of Lorentz Invariance and Quantum Gravity Models  

NASA Technical Reports Server (NTRS)

High energy astrophysics observations provide the best possibilities to detect a very small violation of Lorentz invariance such as may be related to the structure of space-time near the Planck scale of approximately 10(exp -35)m. I will discuss the possible signatures of Lorentz invariance violation (LIV) that can be manifested by observing of the spectra, polarization, and timing of gamma-rays from active galactic nuclei and y-ray bursts. Other sensitive tests are provided by observations of the spectra of ultrahigh energy cosmic rays and neutrinos. Using the latest data from the Pierre Auger Observatory one can already derive an upper limit of 4.5 x 10(exp -23) on the fraction of LIV at a Lorentz factor of approximately 2 x 10(exp 11). This result has fundamental implications for quantum gravity models. I will also discuss the possibilities of using more sensitive space-based detection techniques to improve searches for LIV in the future.

Stecker, F. W.

2011-01-01

171

Adsorption behavior of pesticide methomyl on activated carbon in a high gravity rotating packed bed reactor.  

PubMed

High gravity rotating packed bed (HGRPB) reactor possesses the property of high mass transfer rate, which is expected to promote the adsorption rate for the process. In this study, HGRPB has been applied on adsorption removal of methomyl from solution, adopting the adsorbent of activated carbon F400. The influence of operating parameters of HGRPB on mass transfer such as the rotating speed (N(R)), the flow rate of solution (F(L)) and initial concentration of methomyl (C(b0)) were examined. The traditionally internal mass transfer models combined with Freundlich isotherm were used to predict the surface and effective diffusion coefficients. In addition, the results have also been compared with those obtained from the traditional basket stirred batch reactor (BBR). The results showed that the larger values of N(R) and F(L) enhanced the effective intraparticle diffusion and provided more accessible adsorption sites so as to result in lower equilibrium concentration in HGRPB system when compared to SBR system. The results of adsorption kinetics demonstrated that surface and effective diffusions were both significantly greater in HGRPB system instead of BBR system. Furthermore, the values of Bi(S) also manifested less internal mass transfer resistance in HGRPB system. The contribution ratio (R(F)) of the surface to pore diffusion mass transport showed that the larger contribution resulted from the surface diffusion in HGRPB system. Therefore, the results reasonably led to the conclusion that when the HGRPB system applied on the adsorption of methomyl on F400, the lower equilibrium concentration and faster internal mass transfer can be obtained so as to highly possess great potential to match the gradually stricter environmental standard. PMID:22482495

Chang, Chiung-Fen; Lee, Shu-Chi

2012-06-01

172

Geophysical Delineation of Geothermal Resources in Southern Utah using High-Precision Gravity  

NASA Astrophysics Data System (ADS)

Thermo Hot Springs, an existing 10 MW geothermal resource in southern Utah, is poorly understood with little constraint on subsurface extent and capacity. Subsurface controls of Thermo Hot Springs are thus being explored by gravity and MT surveys. We report on the regional gravity survey comprised of 108 gravity stations, including station reoccupations used to combine modern and historical data. Gravity survey methods have elevation control of better than 0.3 m which allows for gravity accuracy of better than 0.1 mGal. Bouguer anomaly models show a prominent north-south regional trend of 10 to 15 mGal amplitude which is interpreted as a large Basin-and-Range normal fault with downthrow to the west. Northeast of the hot springs there is an elongate east-west trending gravity low of 4 mGal amplitude which is interpreted as a fault with downthrow to the north. These two trends intersect adjacent to the hot springs, and are interpreted to be the structural control of the fluid flow. Modeling of detailed, east-west trending profiles across the hot spring mounds provide a depth-to-basement approximation between 200 and 300 m. For geothermal systems, geophysical surveys are an effective, practical and non-invasive approach to delineate subsurface controls and characterize the resource.

Hardwick, C.; Gettings, P.; Chapman, D. S.

2010-12-01

173

Neptunium estimation in dissolver and high-level-waste solutions  

SciTech Connect

This papers deals with the optimization of the experimental conditions for the estimation of {sup 237}Np in spent-fuel dissolver/high-level waste solutions using thenoyltrifluoroacetone as the extractant. (authors)

Pathak, P.N.; Prabhu, D.R.; Kanekar, A.S.; Manchanda, V.K. [Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai - 400 085 (India)

2008-07-01

174

Towards High-Level Specification & Synthesis of Dynamic Process Logic  

E-print Network

Towards High-Level Specification & Synthesis of Dynamic Process Logic School of Computer Science, The University of Western Australia, Australia Oliver Diessel Usama Malik Keith So George Milne #12;Overview

Diessel, Oliver

175

Effect of Melt Convection at Various Gravity Levels and Orientations on the Forces Acting on a Large Spherical Particle in the Vicinity of a Solidification Interface  

NASA Technical Reports Server (NTRS)

Numerical modeling was Undertaken to analyze the influence of both radial and axial thermal gradients on convection patterns and velocities claiming solidification of pure Al and an Al-4 wt% Cu alloy. The objective of the numerical task was to predict the influence of convective velocity on an insoluble particle near a solid/liquid (s/l) interface. These predictions were then be used to define the minimum gravity level (q) required to investigate the fundamental physics of interactions between a particle and a s/l interface. This is an ongoing NASA founded flight experiment entitled "particle engulfment and pushing by solidifying interfaces (PEP)". Steady-state calculations were performed for different gravity levels and orientations with respect to the gravity vector The furnace configuration used in this analysis is the quench module insert (QMI-1) proposed for the Material Science Research Facility (MSRF) on board the International Space Station (ISS). The general model of binary alloy solidification was based on the finite element code FIDAP. At a low g level of 10(exp -4) g(sub o) (g(sub o) = 9.8 m/square s) maximum melt convection was obtained for an orientation of 90 deg. Calculations showed that even for this worst case orientation the dominant forces acting on the particle are the fundamental drag and interfacial forces.

Bune, Andris V.; Sen, Subhayu; Mukherjee, Sundeep; Catalina, Adrian; Stefanescu, Doru M.

2000-01-01

176

High-Level Synthesis for FPGAs: From Prototyping to Deployment  

Microsoft Academic Search

Escalating system-on-chip design complexity is pushing the design community to raise the level of abstraction beyond register transfer level. Despite the unsuccessful adoptions of early generations of commercial high-level synthesis (HLS) systems, we believe that the tipping point for transitioning to HLS methodology is happening now, especially for field-programmable gate array (FPGA) designs. The latest generation of HLS tools has

Jason Cong; Bin Liu; Stephen Neuendorffer; Juanjo Noguera; Kees A. Vissers; Zhiru Zhang

2011-01-01

177

Measures of effectiveness for high-level fusion  

Microsoft Academic Search

Current advances in technology, sensor collection, data storage, and data distribution have afforded more complex, distributed, and operational information fusion systems (IFSs). IFSs notionally consist of low-level (data collection, registration, and association in time and space) and high-level fusion (user coordination, situational awareness, and mission control). Low-level IFSs typically rely on standard metrics for evaluation such as timeliness, accuracy, and

Erik Blasch; Pierre Valin; Eloi Bosse

2010-01-01

178

Detection Method and Observed Data of High-energy Gamma Rays under the Influence of Quantum Gravity  

NASA Astrophysics Data System (ADS)

The interaction of high-energy particles affected by quantum gravity is argued from the experimental viewpoint of raising a question, ``our detection method for high-energy ?-rays supplies trustworthy observation data and we are now seeing the true image of the universe through high-energy ?-rays?" The modified dispersion relation (MDR) for particles' energy and momentum is applied to the equation of energy-momentum conservation in particle reactions, to study the restriction imposed on the kinematic state of high-energy particles by the Lorentz invariance violation (LIV) due to quantum gravity, as a function of the incident particle energy of the reaction. The result suggests that the interaction utilized for ?-ray detection is not free from the effect of quantum gravity when ?-ray energy is higher than 1013 ~ 1017 eV depending on models of MDR. Discussion is presented on the prospect of finding clear evidence of the LIV effect from ?-ray observations, as well as on the radiation and propagation mechanism of ?-rays under the influence of the LIV effect.

Kifune, T.

2014-05-01

179

MUTATION-BASED VALIDATION OF HIGH-LEVEL MICROPROCESSOR IMPLEMENTATIONS  

E-print Network

MUTATION-BASED VALIDATION OF HIGH-LEVEL MICROPROCESSOR IMPLEMENTATIONS Jorge Campos and Hussain Al-level microprocessor implementation by generating a test sequence for a collection of ab- stract design error models of microprocessors, engineers are forced to validate a larger design space in a shorter time frame. This task becomes

Al-Asaad, Hussain

180

Field Trips as Cognitive Motivators for High Level Science Learning  

ERIC Educational Resources Information Center

Using a composite example of field trips from several years of traveling to Yellowstone with high school biology students, the author illustrates how to raise the cognitive level of science instruction and student learning through science field trips. The author examines what teachers can do to raise the level of both teaching and learning in all…

Hurley, Marlene M.

2006-01-01

181

High-level Coordination Specification Operational semantics for Kanor  

E-print Network

High-level Coordination Specification Operational semantics for Kanor Joseph A. Cottam Eric Holk a different approach: declaratively specifying communication pat- terns. Kanor employs a small set of basic manipulation of low-level details. Actual communication patterns are either forced into pre-set pat- terns when

Lumsdaine, Andrew

182

Production and Properties of Solidified High-Level  

E-print Network

-LEVEL RADIOACTIVE WASTE. LEACHING; RADIOACTIVE WASTE DIS- POSAL; RADIOACTIVE WASTE PROCESSING; REVIEWS; SAFETY; SALT experiments. Examples of the use of the information in safety analysis of disposal in salt formations of disposal of high-level waste in salt domes in Jutland. August 1980 RiSk> National Laboratory, DK-4000

183

High-level power estimation with interconnect effects  

Microsoft Academic Search

We extend earlier work on high-level average power estimation to include the power due to interconnect loading. The resulting technique is a combination of a RTL-level gate count prediction method and average interconnect estimation based on Rent's rule. The method can be adapted to be used with different place and route engines and standard cell libraries. For a number of

Kavel M. Büyük?ahin; Farid N. Najm

2000-01-01

184

Machine Learning Methods for High Level Cyber Situation Awareness  

Microsoft Academic Search

Cyber situation awareness needs to operate at many levels of abstraction. In this chapter, we discuss situation awareness\\u000a at a very high level—the behavior of desktop computer users. Our goal is to develop an awareness of what desktop users are\\u000a doing as they work. Such awareness has many potential applications including

Thomas G. Dietterich; Xinlong Bao; Victoria Keiser; Jianqiang Shen

2010-01-01

185

Machine Learning Methods for High Level Cyber Situation Awareness  

NASA Astrophysics Data System (ADS)

Cyber situation awareness needs to operate at many levels of abstraction. In this chapter, we discuss situation awareness at a very high level—the behavior of desktop computer users. Our goal is to develop an awareness of what desktop users are doing as they work. Such awareness has many potential applications including

Dietterich, Thomas G.; Bao, Xinlong; Keiser, Victoria; Shen, Jianqiang

186

Evolving Automatically High-Level Music Descriptors from Acoustic Signals  

Microsoft Academic Search

High-Level music descriptors are key ingredients fo r music information retrieval systems. Although there is a long tradition in extracting information from acoustic signals, the field of mus ic information extraction is largely heuristic in nature. We present here a heur istic-based generic approach for extracting automatically high-level music descr iptors from acoustic signals. This approach is based on Genetic

François Pachet; Aymeric Zils

2003-01-01

187

High-Level Waste System Process Interface Description  

SciTech Connect

The High-Level Waste System is a set of six different processes interconnected by pipelines. These processes function as one large treatment plant that receives, stores, and treats high-level wastes from various generators at SRS and converts them into forms suitable for final disposal. The three major forms are borosilicate glass, which will be eventually disposed of in a Federal Repository, Saltstone to be buried on site, and treated water effluent that is released to the environment.

d'Entremont, P.D.

1999-01-14

188

Fast fabrication of W-Cu functionally graded material by high-gravity combustion synthesis and melt-infiltration  

NASA Astrophysics Data System (ADS)

W-Cu functionally graded material (FGM, 75 wt% W + 25 wt% Cu—40 wt% W + 60 wt% Cu) has been prepared by a method of high-gravity combustion synthesis and melt-infiltration in a short time (˜5 min). The infiltration mechanism in the high-gravity field was investigated. The W-Cu FGM showed an overall relative density of ˜97% and gradually-varying properties in terms of density, micro hardness, coefficient of thermal expansion. Especially, the W-Cu FGM exhibited a coefficient of thermal expansion between those of W and Cu, and thus could be used as a transition layer between W and Cu to relax the thermal stresses.

Zhao, P.; Guo, S. B.; Liu, G. H.; Chen, Y. X.; Li, J. T.

2014-02-01

189

The effect of high altitude on nasal nitric oxide levels.  

PubMed

The aim of the present study was to investigate whether nasal nitric oxide (nNO) levels change in relation to high altitude in a natural setting where the weather conditions were favorable. The present study included 41 healthy volunteers without a history of acute rhinosinusitis within 3 weeks and nasal polyposis. The study group consisted of 31 males (76 %) and 10 females (24 %) and the mean age of the study population was 38 ± 10 years. The volunteers encamped for 2 days in a mountain village at an altitude of 1,500 m above sea level (masl) and proceeded to highlands at an altitude of 2,200 masl throughout the day. The measurements of nNO were done randomly, either first at the mountain village or at sea level. Each participant had nNO values both at sea level and at high altitude at the end of the study. The nNO values of sea level and high altitude were compared to investigate the effect of high altitude on nNO levels. The mean of average nNO measurements at the high altitude was 74.2 ± 41 parts-per-billion (ppb) and the mean of the measurements at sea level was 93.4 ± 45 ppb. The change in nNO depending on the altitude level was statistically significant (p < 0.001). The current investigation showed that nNO levels were decreased at high altitude even if the weather conditions were favorable, such as temperature, humidity, and wind. PMID:24972544

Altundag, Aytug; Salihoglu, Murat; Cayonu, Melih; Cingi, Cemal; Tekeli, Hakan; Hummel, Thomas

2014-09-01

190

Effects of "extra-mixing" processes on the periods of high-order gravity modes in main-sequence stars  

E-print Network

In main-sequence stars, the chemical composition gradient that develops at the edge of the convective core is responsible for a non-uniform period spacing of high-order gravity modes. In this work we investigate, in the case of a 1.6 Msun star, the effects on the period-spacing of extra mixing processes in the core (such as diffusion and overshooting).

A. Miglio; J. Montalban; A. Noels

2005-10-21

191

An overview of very high level software design methods  

NASA Technical Reports Server (NTRS)

Very High Level design methods emphasize automatic transfer of requirements to formal design specifications, and/or may concentrate on automatic transformation of formal design specifications that include some semantic information of the system into machine executable form. Very high level design methods range from general domain independent methods to approaches implementable for specific applications or domains. Applying AI techniques, abstract programming methods, domain heuristics, software engineering tools, library-based programming and other methods different approaches for higher level software design are being developed. Though one finds that a given approach does not always fall exactly in any specific class, this paper provides a classification for very high level design methods including examples for each class. These methods are analyzed and compared based on their basic approaches, strengths and feasibility for future expansion toward automatic development of software systems.

Asdjodi, Maryam; Hooper, James W.

1988-01-01

192

Water borne transport of high level nuclear waste in very deep borehole disposal of high level nuclear waste  

E-print Network

The purpose of this report is to examine the feasibility of the very deep borehole experiment and to determine if it is a reasonable method of storing high level nuclear waste for an extended period of time. The objective ...

Cabeche, Dion Tunick

2011-01-01

193

Chiral Gravity, Log Gravity and Extremal CFT  

E-print Network

We show that the linearization of all exact solutions of classical chiral gravity around the AdS3 vacuum have positive energy. Non-chiral and negative-energy solutions of the linearized equations are infrared divergent at second order, and so are removed from the spectrum. In other words, chirality is confined and the equations of motion have linearization instabilities. We prove that the only stationary, axially symmetric solutions of chiral gravity are BTZ black holes, which have positive energy. It is further shown that classical log gravity-- the theory with logarithmically relaxed boundary conditions --has finite asymptotic symmetry generators but is not chiral and hence may be dual at the quantum level to a logarithmic CFT. Moreover we show that log gravity contains chiral gravity within it as a decoupled charge superselection sector. We normally evaluate the Euclidean sum over geometries of chiral gravity and show that it gives precisely the holomorphic extremal CFT partition function. The modular invariance and integrality of the expansion coefficients of this partition function are consistent with the existence of an exact quantum theory of chiral gravity. We argue that the problem of quantizing chiral gravity is the holographic dual of the problem of constructing an extremal CFT, while quantizing log gravity is dual to the problem of constructing a logarithmic extremal CFT.

Alexander Maloney; Wei Song; Andrew Strominger

2009-03-26

194

Chiral gravity, log gravity, and extremal CFT  

SciTech Connect

We show that the linearization of all exact solutions of classical chiral gravity around the AdS{sub 3} vacuum have positive energy. Nonchiral and negative-energy solutions of the linearized equations are infrared divergent at second order, and so are removed from the spectrum. In other words, chirality is confined and the equations of motion have linearization instabilities. We prove that the only stationary, axially symmetric solutions of chiral gravity are BTZ black holes, which have positive energy. It is further shown that classical log gravity--the theory with logarithmically relaxed boundary conditions--has finite asymptotic symmetry generators but is not chiral and hence may be dual at the quantum level to a logarithmic conformal field theories (CFT). Moreover we show that log gravity contains chiral gravity within it as a decoupled charge superselection sector. We formally evaluate the Euclidean sum over geometries of chiral gravity and show that it gives precisely the holomorphic extremal CFT partition function. The modular invariance and integrality of the expansion coefficients of this partition function are consistent with the existence of an exact quantum theory of chiral gravity. We argue that the problem of quantizing chiral gravity is the holographic dual of the problem of constructing an extremal CFT, while quantizing log gravity is dual to the problem of constructing a logarithmic extremal CFT.

Maloney, Alexander [Physics Department, McGill University, Montreal, QC H3A 2T8 (Canada); Song Wei [Key Laboratory of Frontiers in Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, 100190 (China); Center for the Fundamental Laws of Nature Jefferson Physical Laboratory, Harvard University, Cambridge, Massachusetts 02138 (United States); Strominger, Andrew [Center for the Fundamental Laws of Nature Jefferson Physical Laboratory, Harvard University, Cambridge, Massachusetts 02138 (United States)

2010-03-15

195

Reducing local hydrology from high-precision gravity measurements: a lysimeter-based approach  

NASA Astrophysics Data System (ADS)

Temporal gravimeter observations, used in geodesy and geophysics to study the Earth's gravity field variations, are influenced by local water storage changes (WSC). At the Geodetic Observatory Wettzell (Germany), WSC in the snow pack, top soil, unsaturated saprolite and fractured aquifer are all important terms of the local water budget. In this study, lysimeter measurements are used for the first time to estimate the hydrological influence on temporal gravimeter observations. Lysimeter data are used to estimate WSC at the field scale in combination with complementary observations and a hydrological 1-D model. From these estimated WSC, we calculate the hydrological gravity response. The results are compared to other methods used in the past to correct temporal gravity observations for the local hydrological influence. Lysimeter measurements significantly improve the independent estimation of WSC and thus provide a better way of reducing the local hydrological effect from gravimeter measurements. We find that the gravity residuals are caused to a larger extent by local WSC than previously stated. At sites where temporal gravity observations are used to study geophysical processes beyond local hydrology, the installation of a lysimeter is recommended.

Creutzfeldt, Benjamin; Güntner, Andreas; Wziontek, Hartmut; Merz, Bruno

2010-10-01

196

High resolution local Moho determination using gravity inversion: A case study in Sri Lanka  

NASA Astrophysics Data System (ADS)

The seismic data incorporated in global Moho models are sparse and therefore the interpolation of global Moho depths on a local area may give unrealistic results, especially in regions without adequate seismic information. Gravity inversion is a useful tool that can be used to determine Moho depths in the mentioned regions. This paper describes an interactive way of local Moho depth determination using the gravity inversion method constrained with available seismic data. Before applying inversion algorithms, the Bouguer gravity data is filtered in various stages that reduce the potential bias usually expected in Moho depth determination using gravity methods with constant density contrast assumption. A test area with reliable seismic data is used to validate the results of Moho computation, and subsequently the same computation procedure is applied to the Sri Lankan region. The results of the test area are in better agreement with seismically determined Moho depths than those obtained by global Moho models. In the Sri Lankan region, Moho determination reveals a fairly uniform thin crust of average thickness around 20 km. The overall result suggests that our gravity inversion method is robust and may be suitable for local Moho determination in virgin regions, especially those without sufficient seismic data.

Prasanna, H. M. I.; Chen, W.; ?z, H. B.

2013-09-01

197

A Testing Instrument for High School Arabic, Level III.  

ERIC Educational Resources Information Center

The Arabic language examination was designed for Jewish immigrants from Syria wishing to satisfy New York State language requirements for high school graduation by indicating their proficiency in Arabic. The test is essentially a translation of a state test of Hebrew, and is intended to test Arabic at the third-year high school level. The…

Wolowelsky, Joel B.

198

Solving High-Level Planning Programs (Extended Abstract)  

E-print Network

2004; Nau 2007; Green 1969; Weld 1999) and agent-oriented high- level programming (Shoham 1993; Lesp´erance et al. 1995; Levesque and Reiter 1998; Rao 1996). Specifically, we propose a framework for high the specification of behavior in a declarative manner, thus providing an abstract, flexi- ble, and powerful

De Giacomo, Giuseppe

199

Neuropsychological divergence of high-level autism and severe dyslexia  

Microsoft Academic Search

The relationship between cognitive deficits in high-level autism and those in learning disabilities has received little attention. To determine whether high-functioning autistic patients and individuals with severe dyslexia display different cognitive characteristics, 10 nonretarded men (mean age 26 years) with infantile autism, residual state, were compared with 15 severely dyslexic men (mean age 22 years) and 25 matched controls on

Judith M. Rumsey; Susan D. Hamburger

1990-01-01

200

PICQUERY: A High Level Query Language for Pictorial Database Management  

Microsoft Academic Search

A reasonably comprehensive set of data accessing and manipulation operations that should be supported by a generalized pictorial database management system (PDBMS) is proposed. A corresponding high-level query language, PICQUERY, is presented and illustrated through examples. PICQUERY has been designed with a flavor similar to QBE as the highly nonprocedural and conservational language for the pictorial database management system PICDMS.

Thomas Joseph; Alfonso F. Cardenas

1988-01-01

201

The effects of high presentation levels on consonant feature transmission.  

PubMed

The effect of high speech presentation levels on consonant recognition and feature transmission was assessed in eight participants with normal hearing. Consonant recognition in noise (0 dB signal-to-noise ratio) was measured at five overall speech levels ranging from 65 to 100 dB SPL. Consistent with the work of others, overall percent correct performance decreased as the presentation level of speech increased [e.g., G. A. Studebaker, R. L. Sherbecoe, D. M. McDaniel, and C. A. Gwaltney, J. Acoust. Soc. Am. 105(4), 2431-2444 (1999)]. Confusion matrices were analyzed in terms of relative percent information transmitted at each speech presentation level, as a function of feature. Six feature sets (voicing, place, nasality, duration, frication, and sonorance) were analyzed. Results showed the feature duration (long consonant duration fricatives) to be most affected by increases in level, while the voicing feature was relatively unaffected by increases in level. In addition, alveolar consonants were substantially affected by level, while palatal consonants were not. While the underlying mechanisms responsible for decreases in performance with level increases are unclear, an analysis of common error patterns at high levels suggests that saturation of the neural response and/or a loss of neural synchrony may play a role. PMID:16240830

Hornsby, Benjamin W Y; Trine, Timothy D; Ohde, Ralph N

2005-09-01

202

The effects of high presentation levels on consonant feature transmission  

NASA Astrophysics Data System (ADS)

The effect of high speech presentation levels on consonant recognition and feature transmission was assessed in eight participants with normal hearing. Consonant recognition in noise (0 dB signal-to-noise ratio) was measured at five overall speech levels ranging from 65 to 100 dB SPL. Consistent with the work of others, overall percent correct performance decreased as the presentation level of speech increased [e.g., G. A. Studebaker, R. L. Sherbecoe, D. M. McDaniel, and C. A. Gwaltney, J. Acoust. Soc. Am. 105(4), 2431-2444 (1999)]. Confusion matrices were analyzed in terms of relative percent information transmitted at each speech presentation level, as a function of feature. Six feature sets (voicing, place, nasality, duration, frication, and sonorance) were analyzed. Results showed the feature duration (long consonant duration fricatives) to be most affected by increases in level, while the voicing feature was relatively unaffected by increases in level. In addition, alveolar consonants were substantially affected by level, while palatal consonants were not. While the underlying mechanisms responsible for decreases in performance with level increases are unclear, an analysis of common error patterns at high levels suggests that saturation of the neural response and/or a loss of neural synchrony may play a role.

Hornsby, Benjamin W. Y.; Trine, Timothy D.; Ohde, Ralph N.

2005-09-01

203

Energy Performance and Comfort Level in High Rise and Highly Glazed Office Buildings  

E-print Network

Thermal and visual comfort in buildings play a significant role on occupants' performance but on the other hand achieving energy savings and high comfort levels can be a quite difficult task especially in high rise buildings with highly glazed...

Bayraktar, M.; Perino, M.; Yilmaz, A. Z.

2010-01-01

204

Reflection surveys conducted on the western side of the mid-continental gravity high  

SciTech Connect

The few spatially isolated deeper drill holes available on the western side of the mid-continental gravity high have established elevation changes in the Sioux quartzite that exceed 500m within a few hundred kilometers. Thirteen, 12-fold, CMP, reflection surveys were conducted within this area to supplement the limited drilling data. These surveys used an elastic wave generator as the energy source and a digital 24 channel IFP system for recording. The survey locations were selected to best supplement the existing drill hole data. Phone spacings and near offsets were selected on the basis of walk-out surveys conducted at each reflection site. No velocity control was available and the stacking velocities were selected based on graded velocity stacks. Interval velocities, constrained by general stratigraphic considerations, were calculated from the stacking velocities. For the near surface, interval velocities were extracted from the first arrivals. The lack of velocity control did not appear to seriously degrade the interpretation of gross structural features. Both the Sioux quartzite and a deeper interface, assumed to be the top of igneous basement, were reliably mapped. The two-way times of the basement reflector varied from 400m sec to 200m sec, approximately 500m to 300m respectively. The two-way times to the top of the quartzite varied from 300 m secs to 135m secs, approximately 350m to 160m respectively. The results suggest a major northeast, southwest trending basement fault with displacements exceeding 100m. The structure of both the basement and the quartzite appear to be a faulted anticline or dome. The reflection surveys provided a cost effective method for reconnaissance studies required to establish gross structural features.

Taylor, R.W.; Fromm, A.J. (Fromm Applied Technology, Mequon, WI (United States)); Okita, P. (PHP Minerals, Herndon, VA (United States))

1992-01-01

205

Sensorimotor aspects of high-speed artificial gravity: III. Sensorimotor adaptation  

NASA Technical Reports Server (NTRS)

As a countermeasure to the debilitating physiological effects of weightlessness, astronauts could live continuously in an artificial gravity environment created by slow rotation of an entire spacecraft or be exposed to brief daily "doses" in a short radius centrifuge housed within a non-rotating spacecraft. A potential drawback to both approaches is that head movements made during rotation may be disorienting and nauseogenic. These side effects are more severe at higher rotation rates, especially upon first exposure. Head movements during rotation generate aberrant vestibular stimulation and Coriolis force perturbations of the head-neck motor system. This article reviews our progress toward distinguishing vestibular and motor factors in side effects of rotation, and presents new data concerning the rates of rotation up to which adaptation is possible. We have studied subjects pointing to targets during constant velocity rotation, because these movements generate Coriolis motor perturbations of the arm but do not involve unusual vestibular stimulation. Initially, reaching paths and endpoints are deviated in the direction of the transient lateral Coriolis forces generated. With practice, subjects soon move in straighter paths and land on target once more. If sight of the arm is permitted, adaptation is more rapid than in darkness. Initial arm movement trajectory and endpoint deviations are proportional to Coriolis force magnitude over a range of rotation speeds from 5 to 20 rpm, and there is rapid, complete motor adaptation at all speeds. These new results indicate that motor adaptation to high rotation rates is possible. Coriolis force perturbations of head movements also occur in a rotating environment but adaptation gradually develops over the course of many head movements.

DiZio, Paul; Lackner, James R.; Young, L. R. (Principal Investigator)

2002-01-01

206

High-resolution residual geoid and gravity anomaly data of the northern Indian Ocean - An input to geological understanding  

NASA Astrophysics Data System (ADS)

Geoid data are more sensitive to density distributions deep within the Earth, thus the data are useful for studying the internal processes of the Earth leading to formation of geological structures. In this paper, we present much improved version of high resolution (1' × 1') geoid anomaly map of the northern Indian Ocean generated from the altimeter data obtained from Geodetic Missions of GEOSAT and ERS-1 along with ERS-2, TOPEX/POSIDEON and JASON satellites. The geoid map of the Indian Ocean is dominated by a significant low of -106 m south of Sri Lanka, named as the Indian Ocean Geoid Low (IOGL), whose origin is not clearly known yet. The residual geoid data are retrieved from the geoid data by removing the long-wavelength core-mantle density effects using recent spherical harmonic coefficients of Earth Gravity Model 2008 (EGM2008) up to degree and order 50 from the observed geoid data. The coefficients are smoothly rolled off between degrees 30-70 in order to avoid artifacts related to the sharp truncation at degree 50. With this process we observed significant improvement in the residual geoid data when compared to the previous low-spatial resolution maps. The previous version was superposed by systematic broad regional highs and lows (like checker board) with amplitude up to ±12 m, though the trends of geoid in general match in both versions. These methodical artifacts in the previous version may have arisen due to the use of old Rapp's geo-potential model coefficients, as well as sharp truncation of reference model at degree and order 50. Geoid anomalies are converted to free-air gravity anomalies and validated with cross-over corrected ship-borne gravity data of the Arabian Sea and Bay of Bengal. The present satellite derived gravity data matches well with the ship-borne data with Root Mean Square Error (RMSE) of 5.1-7.8 mGal, and this is found to be within the error limits when compared with other globally available satellite data. Spectral analysis of ship-borne and satellite data suggested that the satellite gravity data have a resolution down to 16-18 km. Further, the geoid, residual geoid and gravity anomalies are integrated with seismic data along two profiles in the Bay of Bengal and Arabian Sea, and inferences have been made in terms of density distributions at different depths. The new residual geoid anomaly map shows excellent correlation with regional tectonic features such as Sunda subduction zone, volcanic traces (Chagos-Laccadive, Ninetyeast and 85°E ridges) and mid-ocean ridge systems (Central Indian and Carlsberg ridges).

Sreejith, K. M.; Rajesh, S.; Majumdar, T. J.; Srinivasa Rao, G.; Radhakrishna, M.; Krishna, K. S.; Rajawat, A. S.

2013-01-01

207

Evaluation of the fermentation of high gravity thick sugar beet juice worts for efficient bioethanol production  

PubMed Central

Background Sugar beet and intermediates of sugar beet processing are considered to be very attractive feedstock for ethanol production due to their content of fermentable sugars. In particular, the processing of the intermediates into ethanol is considerably facilitated because it does not require pretreatment or enzymatic treatment in contrast to production from starch raw materials. Moreover, the advantage of thick juice is high solid substance and saccharose content which eliminates problems with the storability of this feedstock. Results The objective of this study were to investigate bioethanol production from thick juice worts and the effects of their concentration, the type of mineral supplement, as well as the dose of yeast inoculum on fermentation dynamics and ethanol yield. The obtained results show that to ensure efficient ethanolic fermentation of high gravity thick juice worts, one needs to use a yeast strain with high ethanol tolerance and a large amount of inoculum. The highest ethanol yield (94.9?±?2.8% of the theoretical yield) and sugars intake of 96.5?±?2.9% were obtained after the fermentation of wort with an extract content of 250 g/kg supplemented with diammonium hydrogen phosphate (0.3 g/L of wort) and inoculated with 2 g of Ethanol Red dry yeast per L of wort. An increase in extract content in the fermentation medium from 250 g/L to 280 g/kg resulted in decreased efficiency of the process. Also the distillates originating from worts with an extract content of 250 g/kg were characterized by lower acetaldehyde concentration than those obtained from worts with an extract content of 280 g/kg. Conclusions Under the favorable conditions determined in our experiments, 38.9?±?1.2 L of 100% (v/v) ethyl alcohol can be produced from 100 kg of thick juice. The obtained results show that the selection of process conditions and the yeast for the fermentation of worts with a higher sugar content can improve the economic performance of the alcohol-distilling industry due to more efficient ethanol production, reduced consumption of cooling water, and energy for ethanol distillation, as well as a decreased volume of fermentation stillage. PMID:24206573

2013-01-01

208

(abstract) Venus Gravity Field  

NASA Technical Reports Server (NTRS)

A global gravity field model of Venus to degree and order 75 (5772 spherical harmonic coefficients) has been estimated from Doppler radio tracking of the orbiting spacecraft Pioneer Venus Orbiter (1979-1992) and Magellan (1990-1994). After the successful aerobraking of Magellan, a near circular polar orbit was attained and relatively uniform gravity field resolution (approximately 200 km) was obtained with formal uncertainties of a few milligals. Detailed gravity for several highland features are displayed as gravity contours overlaying colored topography. The positive correlation of typography with gravity is very high being unlike that of the Earth, Moon, and Mars. The amplitudes are Earth-like, but have significantly different gravity-topography ratios for different features. Global gravity, geoid, and isostatic anomaly maps as well as the admittance function are displayed.

Konopliv, A. S.; Sjogren, W. L.

1995-01-01

209

Application of low-cost algal nitrogen source feeding in fuel ethanol production using high gravity sweet potato medium.  

PubMed

Protein-rich bloom algae biomass was employed as nitrogen source in fuel ethanol fermentation using high gravity sweet potato medium containing 210.0 g l(-1) glucose. In batch mode, the fermentation could not accomplish even in 120 h without any feeding of nitrogen source. While, the feeding of acid-hydrolyzed bloom algae powder (AHBAP) notably promoted fermentation process but untreated bloom algae powder (UBAP) was less effective than AHBAP. The fermentation times were reduced to 96, 72, and 72 h if 5.0, 10.0, and 20.0 g l(-1) AHBAP were added into medium, respectively, and the ethanol yields and productivities increased with increasing amount of feeding AHBAP. The continuous fermentations were performed in a three-stage reactor system. Final concentrations of ethanol up to 103.2 and 104.3 g l(-1) with 4.4 and 5.3 g l(-1) residual glucose were obtained using the previously mentioned medium feeding with 20.0 and 30.0 g l(-1) AHBAP, at dilution rate of 0.02 h(-1). Notably, only 78.5 g l(-1) ethanol and 41.6 g l(-1) residual glucose were obtained in the comparative test without any nitrogen source feeding. Amino acids analysis showed that approximately 67% of the protein in the algal biomass was hydrolyzed and released into the medium, serving as the available nitrogen nutrition for yeast growth and metabolism. Both batch and continuous fermentations showed similar fermentation parameters when 20.0 and 30.0 g l(-1) AHBAP were fed, indicating that the level of available nitrogen in the medium should be limited, and an algal nitrogen source feeding amount higher than 20.0 g l(-1) did not further improve the fermentation performance. PMID:22387426

Shen, Yu; Guo, Jin-Song; Chen, You-Peng; Zhang, Hai-Dong; Zheng, Xu-Xu; Zhang, Xian-Ming; Bai, Feng-Wu

2012-08-31

210

Mercury levels in high-end consumers of fish.  

PubMed Central

Consumption of food containing mercury has been identified as a health risk. The U.S. Environmental Protection Agency (U.S. EPA) and the National Academy of Sciences recommend keeping the whole blood mercury level < 5.0 microg/L or the hair level < 1.0 microg/g. This corresponds to a reference dose (RfD) of 0.1 microg/kg body weight per day. All patients in a 1-year period (n = 720) who came for an office visit in a private internal medicine practice in San Francisco, California, were evaluated for mercury excess using the current RfD. One hundred twenty-three patients were tested (93 females, 30 males). Of these, data were statistically analyzed for 89 subjects. Mercury levels ranged from 2.0 to 89.5 microg/L for the 89 subjects. The mean for 66 women was 15 microg/L [standard deviation (SD) = 15], and for 23 men was 13 microg/L (SD = 5); 89% had levels exceeding the RfD. Subjects consumed 30 different forms or types of fish. Swordfish had the highest correlation with mercury level. Sixty-seven patients with serial blood levels over time after stopping fish showed a decline in mercury levels; reduction was significant (p < 0.0001). A substantial fraction of patients had diets high in fish consumption; of these, a high proportion had blood mercury levels exceeding the maximum level recommended by the U.S. EPA and National Academy of Sciences. The mean level for women in this survey was 10 times that of mercury levels found in a recent population survey by the U.S. Centers for Disease Control and Prevention. Some children were > 40 times the national mean. PMID:12676623

Hightower, Jane M; Moore, Dan

2003-01-01

211

Venus - Multiple Views of High-level Clouds  

NASA Technical Reports Server (NTRS)

This series of pictures shows four views of the planet Venus obtained by Galileo's Solid State Imaging System at ranges of 1.4 to 2 million miles as the spacecraft receded from Venus. The pictures in the top row were taken about 4 and 5 days after closest approach; those in the bottom row were taken about 6 days out, 2 hours apart. In these violet-light images, north is at the top and the evening terminator to the left. The cloud features high in the planet's atmosphere rotate from right to left, from the limb through the noon meridian toward the terminator, traveling all the way around the planet once every four days. The motion can be seen by comparing the last two pictures, taken two hours apart. The other views show entirely different faces of Venus. These photographs are part of the 'Venus global circulation' sequence planned by the imaging team. The Galileo Project is managed for NASA's Office of Space Science and Applications by the Jet Propulsion Laboratory; its mission is to study Jupiter and its satellites and magnetosphere after multiple gravity-assist flybys at Venus and Earth.

1990-01-01

212

High-level software energy macro-modeling  

Microsoft Academic Search

This paper presents an efficient and accurate high-level software energy estimation methodology using the concept of characterization-based macro-modeling. In characterization-based macro-modeling, a function or sub-routine is characterized using an accurate lower-level energy model of the target processor, to construct a macro-model that relates the energy consumed in the function under consideration to various parameters that can be easily observed or

T. K. Tant; A. Raghunathan; G. Lakshminarayana; N. K. Jha

2001-01-01

213

Solidification of Savannah River plant high level waste  

NASA Astrophysics Data System (ADS)

Authorization for construction of the Defense Waste Processing Facility (DWPF) is expected in FY-83. The optimum time for stage 2 authorization is about three years later. Detailed design and construction will require approximately five years for stage 1, with stage 2 construction completed about two to three years later. Production of canisters of waste glass would begin in 1988, and the existing backlog of high level waste sludge stored at SRP would be worked off by about the year 2000. Stage 2 operation could begin in 1990. The technology and engineering are ready for construction and eventual operation of the DWPF for immobilizing high level radioactive waste at Savannah River Plant (SRP). Proceeding with this project will provide the public, and the leadership of this country, with a crucial demonstration that a major quanitity of existing high level nuclear wastes can be safely and permanently immobilized.

Maher, R.; Shafranek, L. F.; Kelley, J. A.; Zeyfang, R. W.

1981-11-01

214

Final report on cermet high-level waste forms  

SciTech Connect

Cermets are being developed as an alternate method for the fixation of defense and commercial high level radioactive waste in a terminal disposal form. Following initial feasibility assessments of this waste form, consisting of ceramic particles dispersed in an iron-nickel base alloy, significantly improved processing methods were developed. The characterization of cermets has continued through property determinations on samples prepared by various methods from a variety of simulated and actual high-level wastes. This report describes the status of development of the cermet waste form as it has evolved since 1977. 6 tables, 18 figures.

Kobisk, E.H.; Quinby, T.C.; Aaron, W.S.

1981-08-01

215

Building high-level features using large scale unsupervised learning  

E-print Network

We consider the problem of building detectors for high-level concepts using only unsupervised feature learning. For example, we would like to understand if it is possible to learn a face detector using only unlabeled images downloaded from the internet. To answer this question, we trained a simple feature learning algorithm on a large dataset of images (10 million images, each image is 200x200). The simulation is performed on a cluster of 1000 machines with fast network hardware for one week. Extensive experimental results reveal surprising evidence that such high-level concepts can indeed be learned using only unlabeled data and a simple learning algorithm.

Le, Quoc V; Devin, Matthieu; Corrado, Greg; Chen, Kai; Ranzato, Marc'Aurelio; Dean, Jeff; Ng, Andrew Y

2011-01-01

216

High Level Waste (HLW) Feed Process Control Strategy  

SciTech Connect

The primary purpose of this document is to describe the overall process control strategy for monitoring and controlling the functions associated with the Phase 1B high-level waste feed delivery. This document provides the basis for process monitoring and control functions and requirements needed throughput the double-shell tank system during Phase 1 high-level waste feed delivery. This document is intended to be used by (1) the developers of the future Process Control Plan and (2) the developers of the monitoring and control system.

STAEHR, T.W.

2000-06-14

217

Integration of P- and SH-wave high-resolution seismic reflection and micro-gravity techniques to improve interpretation of shallow subsurface structure: New Madrid seismic zone  

USGS Publications Warehouse

Shallow high-resolution seismic reflection surveys have traditionally been restricted to either compressional (P) or horizontally polarized shear (SH) waves in order to produce 2-D images of subsurface structure. The northernmost Mississippi embayment and coincident New Madrid seismic zone (NMSZ) provide an ideal laboratory to study the experimental use of integrating P- and SH-wave seismic profiles, integrated, where practicable, with micro-gravity data. In this area, the relation between "deeper" deformation of Paleozoic bedrock associated with the formation of the Reelfoot rift and NMSZ seismicity and "shallower" deformation of overlying sediments has remained elusive, but could be revealed using integrated P- and SH-wave reflection. Surface expressions of deformation are almost non-existent in this region, which makes seismic reflection surveying the only means of detecting structures that are possibly pertinent to seismic hazard assessment. Since P- and SH-waves respond differently to the rock and fluid properties and travel at dissimilar speeds, the resulting seismic profiles provide complementary views of the subsurface based on different levels of resolution and imaging capability. P-wave profiles acquired in southwestern Illinois and western Kentucky (USA) detect faulting of deep, Paleozoic bedrock and Cretaceous reflectors while coincident SH-wave surveys show that this deformation propagates higher into overlying Tertiary and Quaternary strata. Forward modeling of micro-gravity data acquired along one of the seismic profiles further supports an interpretation of faulting of bedrock and Cretaceous strata. The integration of the two seismic and the micro-gravity methods therefore increases the scope for investigating the relation between the older and younger deformation in an area of critical seismic hazard. ?? 2006 Elsevier B.V. All rights reserved.

Bexfield, C.E.; McBride, J.H.; Pugin, A.J.M.; Ravat, D.; Biswas, S.; Nelson, W.J.; Larson, T.H.; Sargent, S.L.; Fillerup, M.A.; Tingey, B.E.; Wald, L.; Northcott, M.L.; South, J.V.; Okure, M.S.; Chandler, M.R.

2006-01-01

218

Low-Level Information and High-Level Perception: The Case of Speech in Noise  

PubMed Central

Auditory information is processed in a fine-to-crude hierarchical scheme, from low-level acoustic information to high-level abstract representations, such as phonological labels. We now ask whether fine acoustic information, which is not retained at high levels, can still be used to extract speech from noise. Previous theories suggested either full availability of low-level information or availability that is limited by task difficulty. We propose a third alternative, based on the Reverse Hierarchy Theory (RHT), originally derived to describe the relations between the processing hierarchy and visual perception. RHT asserts that only the higher levels of the hierarchy are immediately available for perception. Direct access to low-level information requires specific conditions, and can be achieved only at the cost of concurrent comprehension. We tested the predictions of these three views in a series of experiments in which we measured the benefits from utilizing low-level binaural information for speech perception, and compared it to that predicted from a model of the early auditory system. Only auditory RHT could account for the full pattern of the results, suggesting that similar defaults and tradeoffs underlie the relations between hierarchical processing and perception in the visual and auditory modalities. PMID:18494561

Nahum, Mor; Nelken, Israel; Ahissar, Merav

2008-01-01

219

Low voltage to high voltage level shifter and related methods  

NASA Technical Reports Server (NTRS)

A shifter circuit comprises a high and low voltage buffer stages and an output buffer stage. The high voltage buffer stage comprises multiple transistors arranged in a transistor stack having a plurality of intermediate nodes connecting individual transistors along the stack. The transistor stack is connected between a voltage level being shifted to and an input voltage. An inverter of this stage comprises multiple inputs and an output. Inverter inputs are connected to a respective intermediate node of the transistor stack. The low voltage buffer stage has an input connected to the input voltage and an output, and is operably connected to the high voltage buffer stage. The low voltage buffer stage is connected between a voltage level being shifted away from and a lower voltage. The output buffer stage is driven by the outputs of the high voltage buffer stage inverter and the low voltage buffer stage.

Mentze, Erik J. (Inventor); Hess, Herbert L. (Inventor); Buck, Kevin M. (Inventor); Cox, David F. (Inventor)

2006-01-01

220

One centimeter-level observations of diurnal ocean tides from global monthly mean time-variable gravity fields  

Microsoft Academic Search

A method of analyzing GRACE satellite-to-satellite ranging data is presented which accentuates signals from diurnal ocean\\u000a tides and dampens signals from long-period non-tidal phenomena. We form a time series of differences between two independent\\u000a monthly mean gravity solutions, one set computed from range-rate data along strictly ascending arcs and the other set computed\\u000a from data along descending arcs. The solar

Shin-Chan Han; Richard D. Ray; Scott B. Luthcke

2010-01-01

221

High levels of fluctuating asymmetry in isolated stickleback populations  

PubMed Central

Background Fluctuating asymmetry (FA), defined as small random deviations from the ideal bilateral symmetry, has been hypothesized to increase in response to both genetic and environmental stress experienced by a population. We compared levels of FA in 12 bilateral meristic traits (viz. lateral-line system neuromasts and lateral plates), and heterozygosity in 23 microsatellite loci, among four marine (high piscine predation risk) and four pond (zero piscine predation risk) populations of nine-spined sticklebacks (Pungitius pungitius). Results Pond sticklebacks had on average three times higher levels of FA than marine fish and this difference was highly significant. Heterozygosity in microsatellite markers was on average two times lower in pond (HE ? 0.3) than in marine (HE ? 0.6) populations, and levels of FA and heterozygosity were negatively correlated across populations. However, after controlling for habitat effect on heterozygosity, levels of FA and heterozygosity were uncorrelated. Conclusions The fact that levels of FA in traits likely to be important in the context of predator evasion were elevated in ponds compared to marine populations suggests that relaxed selection for homeostasis in ponds lacking predatory fish may be responsible for the observed habitat difference in levels of FA. This inference also aligns with the observation that the levels of genetic variability across the populations did not explain population differences in levels of FA after correcting for habitat effect. Hence, while differences in strength of selection, rather than in the degree of genetic stress could be argued to explain habitat differences in levels of FA, the hypothesis that increased FA in ponds is caused by genetic stress cannot be rejected. PMID:22788717

2012-01-01

222

Relationship between plasma insulin levels and high density lipoprotein cholesterol levels in healthy men  

Microsoft Academic Search

Summary  Insulin and high density lipoproteins are considered to play a role in the development of atherosclerosis. In order to study whether there was a relationship between endogenous plasma insulin response and high density lipoproteins, an acute intravenous glucose tolerance test (0.5 g glucose\\/kg body weight) was performed in 94 healthy men, aged 20–49 years. Cholesterol and triglyceride levels were measured

M. Stalder; D. Pometta; A. Suenram

1981-01-01

223

Feeling Gravity's Pull: Gravity Modeling. The Gravity Field of Mars  

NASA Technical Reports Server (NTRS)

Most people take the constant presence of gravitys pull for granted. However, the Earth's gravitational strength actually varies from location to location. This variation occurs because mass, which influences an object's gravitational pull, is not evenly distributed within the planet. Changes in topography, such as glacial movement, an earthquake, or a rise in the ocean level, can subtly affect the gravity field. An accurate measurement of the Earth's gravity field helps us understand the distribution of mass beneath the surface. This insight can assist us in locating petroleum, mineral deposits, ground water, and other valuable substances. Gravity mapping can also help notice or verify changes in sea surface height and other ocean characteristics. Such changes may indicate climate change from polar ice melting and other phenomena. In addition, gravity mapping can indicate how land moves under the surface after earthquakes and other plate tectonic processes. Finally, changes in the Earth's gravity field might indicate a shift in water distribution that could affect agriculture, water supplies for population centers, and long-term weather prediction. Scientists can map out the Earth's gravity field by watching satellite orbits. When a satellite shifts in vertical position, it might be passing over an area where gravity changes in strength. Gravity is only one factor that may shape a satellite's orbital path. To derive a gravity measurement from satellite movement, scientists must remove other factors that might affect a satellite's position: 1. Drag from atmospheric friction. 2. Pressure from solar radiation as it heads toward Earth and. as it is reflected off the surface of the Earth 3. Gravitational pull from the Sun, the Moon, and other planets in the Solar System. 4. The effect of tides. 5. Relativistic effects. Scientists must also correct for the satellite tracking process. For example, the tracking signal must be corrected for refraction through the atmosphere of the Earth. Supercomputers can calculate the effect of gravity for specific locations in space following a mathematical process known as spherical harmonics, which quantifies the gravity field of a planetary body. The process is based on Laplace's fundamental differential equation of gravity. The accuracy of a spherical harmonic solution is rated by its degree and order. Minute variations in gravity are measured against the geoid, a surface of constant gravity acceleration at mean sea level. The geoid reference gravity model strength includes the central body gravitational attraction (9.8 m/sq s) and a geopotential variation in latitude partially caused by the rotation of the Earth. The rotational effect modifies the shape of the geoid to be more like an ellipsoid, rather than a perfect, circle. Variations of gravity strength from the ellipsoidal reference model are measured in units called milli-Galileos (mGals). One mGal equals 10(exp -5) m/sq s. Research projects have also measured the gravity fields of other planetary bodies, as noted in the user profile that follows. From this information, we may make inferences about our own planet's internal structure and evolution. Moreover, mapping the gravity fields of other planets can help scientists plot the most fuel-efficient course for spacecraft expeditions to those planets.

Lemoine, Frank; Smith, David; Rowlands, David; Zuber, Maria; Neumann, G.; Chinn, Douglas; Pavlis, D.

2000-01-01

224

The Estuary Guide. Level 3: High School. Draft.  

ERIC Educational Resources Information Center

Estuaries are marine systems that serve as nurseries for animals, links in the migratory pathways, and habitat for a complex community of organisms. This curriculum guide intended for use at the high school level seeks to teach what estuaries are; provide opportunities to practice decision-making that affects estuaries; and encourage students to…

Alexander, Glen; And Others

225

High-level attention Attention in complex tasks  

E-print Network

is difficult ­ Attention Deficit/Hyperactivity Disorder ­ A deficit in this ability to select and sustain1 High-level attention · Attention in complex tasks · Central executive function · Attention deficits · Automaticity Playing a sport · When you first learn to play basketball you have to attend to too

Pillow, Jonathan

226

The R Environment A high-level overview  

E-print Network

The R Environment A high-level overview Deepayan Sarkar Indian Statistical Institute, Delhi 6 October 2010 Deepayan Sarkar The R Environment #12;An article in the New York Times #12;From the article R use it. #12;What exactly is R? R is a language and environment for statistical computing and graphics

Bandyopadhyay, Antar

227

Are High-level Languages suitable for Robust Telecoms Software?  

E-print Network

product development must minimise time to market while delivering high levels of dependability-trivial distributed telecoms application, a Dis- patch Call Controller (DCC) measured on a Beowulf cluster. Our inves- tigations show that the Erlang implementation meets the DCC's resource reclamation and soft real-time

Trinder, Phil

228

High-Level waste process and product data annotated bibliography  

SciTech Connect

The objective of this document is to provide information on available issued documents that will assist interested parties in finding available data on high-level waste and transuranic waste feed compositions, properties, behavior in candidate processing operations, and behavior on candidate product glasses made from those wastes. This initial compilation is only a partial list of available references.

Stegen, G.E.

1996-02-13

229

Studies of Mercury in High Level Waste Systems  

Microsoft Academic Search

Historically, mercury was added to the nuclear weapons processing as a catalyst for the dissolution of aluminum metal. After neutralization the mercury was disposed to the High Level Waste tanks where its speciation led to mercuric oxides\\/hydroxides in the sludge and a small soluble mercuric ion concentration in the alkaline supernate. This report in its original revision described a three-pronged

2004-01-01

230

A Preview of High School Level Economic Software.  

ERIC Educational Resources Information Center

The purpose of this study was to locate and evaluate high-school-level economic software compatible with an Apple II or IIe computer. To identify software, computer searches were run, bibliographies were scanned, and reviews were collected. Only software that was recommended by some outside source was included in the evaluation. The following…

Kincade, Jeannine H.

231

High-level nuclear waste management: analysis of options  

Microsoft Academic Search

A new approach is introduced for evaluating strategies for the safe disposal of high-level nuclear waste. Five strategies are considered, and by means of the effective method of 'analytic hierarchy process' these strategies are prioritized with respect to a set of tangible and intangible criteria. The results are compared with criteria adopted by the United States Department of Energy. The

T L Saaty; H Gholamnezhad

1982-01-01

232

Level 1 Tornado PRA for the High Flux Beam Reactor  

Microsoft Academic Search

This report describes a risk analysis primarily directed at providing an estimate for the frequency of tornado induced damage to the core of the High Flux Beam Reactor (HFBR), and thus it constitutes a Level 1 Probabilistic Risk Assessment (PRA) covering tornado induced accident sequences. The basic methodology of the risk analysis was to develop a ``tornado specific`` plant logic

G. E. Bozoki; C. S. Conrad

1994-01-01

233

High-Level Wellness: The Good Life in Higher Education.  

ERIC Educational Resources Information Center

Verbal evaluations of a minicourse on life-style education revealed that students found the course to be valuable and enjoyable. Results suggest that the adoption of a high-level wellness life-style can directly affect individual longevity and quality of life. (Author)

Krivoski, James F.; Piccolo, Nicholas A.

1980-01-01

234

High-Level Data Races Cyrille Artho1  

E-print Network

High-Level Data Races Cyrille Artho1 , Klaus Havelund2 , and Armin Biere1 1 Computer Systems, California USA Abstract. Data races are a common problem in concurrent programming. Ex- perience shows that the notion of data race is not powerful enough to capture certain types of inconsistencies occurring

Biere, Armin

235

Testability analysis in high level data path synthesis  

Microsoft Academic Search

This article discusses the cooperation of testability and High Level Data Path Synthesis (HLDPS). A particular target domain, namely real time digital signal processing, is addressed where the generation of customized data path compositions is one of the crucial steps during the HLDPS. Taking the testability cost into account during the HLDPS strongly depends on the test generation tool in

Johannes Steensma; Werner Geurts; Francky Catthoor; Hugo De Man

1993-01-01

236

THE XAL INFRASTRUCTURE FOR HIGH LEVEL CONTROL ROOM APPLICATIONS  

SciTech Connect

XAL is a Java programming framework for building high-level control applications related to accelerator physics. The structure, details of implementation, and interaction between components, auxiliary XAL packages, and the latest modifications are discussed. A general overview of XAL applications created for the SNS project is presented.

Shishlo, Andrei P [ORNL] [ORNL; Allen, Christopher K [ORNL] [ORNL; Chu, Paul [Stanford University] [Stanford University; Galambos, John D [ORNL] [ORNL; Pelaia II, Tom [ORNL] [ORNL

2009-01-01

237

A Novel MultiLevel High Voltage Pulsed Power Generator  

Microsoft Academic Search

This paper presents a novel solid-state and high power pulse generation technique that is suitable for a wide range of pulsed power applications. The technique, termed as multi-level pulsed power converter, can be considered as a hybrid of the direct discharge type and the Marx generator but with considerably less complexity in both control and circuitry. It has the ability

D. J. Thrimawithana; U. K. Madawala

2007-01-01

238

High level cognitive information processing in neural networks  

NASA Technical Reports Server (NTRS)

Two related research efforts were addressed: (1) high-level connectionist cognitive modeling; and (2) local neural circuit modeling. The goals of the first effort were to develop connectionist models of high-level cognitive processes such as problem solving or natural language understanding, and to understand the computational requirements of such models. The goals of the second effort were to develop biologically-realistic model of local neural circuits, and to understand the computational behavior of such models. In keeping with the nature of NASA's Innovative Research Program, all the work conducted under the grant was highly innovative. For instance, the following ideas, all summarized, are contributions to the study of connectionist/neural networks: (1) the temporal-winner-take-all, relative-position encoding, and pattern-similarity association techniques; (2) the importation of logical combinators into connection; (3) the use of analogy-based reasoning as a bridge across the gap between the traditional symbolic paradigm and the connectionist paradigm; and (4) the application of connectionism to the domain of belief representation/reasoning. The work on local neural circuit modeling also departs significantly from the work of related researchers. In particular, its concentration on low-level neural phenomena that could support high-level cognitive processing is unusual within the area of biological local circuit modeling, and also serves to expand the horizons of the artificial neural net field.

Barnden, John A.; Fields, Christopher A.

1992-01-01

239

Implementing the High Level Architecture in the Virtual Test Bed  

Microsoft Academic Search

The Virtual Test Bed (VTB) is a prototype of a virtual en- gineering environment to study operations of current and future space vehicles, spaceports, and ranges. The High- Level Architecture (HLA) as defined by the Department of Defense (DoD), is the main environment. The VTB\\/HLA implementation described here represents different systems that interact in the simulation of a Space Shuttle

José A. Sepúlveda; Luis C. Rabelo; Frank Riddick; Cary J. Peaden

2004-01-01

240

High Level Programming and Control of a Manufacturing System  

Microsoft Academic Search

Now, at the beginning of the new millennium the importance of robotic and mechatronic systems in the automation of production is getting more obvious. Until today, major research was conducted in making industrial manufacturing more intelligent and particularly in the control of machine systems. In this paper is described a high-level programming approach and control system of a manufacturing robotics

GEORGE K. ADAM; NIKOS E. MASTORAKIS

2003-01-01

241

High-level speaker verification with support vector machines  

Microsoft Academic Search

Recently, high-level features such as word idiolect, pronunciation, phone usage, prosody, etc., have been successfully used in speaker verification. The benefit of these features was demonstrated in the NIST extended data task for speaker verification; with enough conversational data, a recognition system can become \\

W. M. Campbell; J. R. Campbell; D. A. Reynolds; D. A. Jones; T. R. Leek

2004-01-01

242

MIXING PROCESSES IN HIGH-LEVEL WASTE TANKS  

EPA Science Inventory

Flammable gases can be generated in DOE high-level waste tanks, including radiolytic hydrogen, and during cesium precipitation from salt solutions, benzene. Under normal operating conditions the potential for deflagration or detonation from these gases is precluded by purging and...

243

Thermal behavior of BAW filters at high RF power levels.  

PubMed

The temperature increase of bulk acoustic wave filters at high RF power levels has been investigated. Self-heating due to power dissipation in the filter leads to a nonuniform frequency shift of the insertion loss. At the right filter skirt, self-heating is amplified by the negative temperature coefficient of frequency. We demonstrate that at high RF power levels, this can cause thermal instabilities resulting in an abrupt step in the insertion loss. A novel frequency transformation is introduced to describe the nonuniform frequency shift of the insertion loss as well as the thermal instabilities. A condition for the occurrence of thermal instabilities is derived. It is argued that because of this nonuniform frequency shift at high power levels, accelerated lifetime tests can overestimate the lifetime, if the stress frequency is not compensated for self-heating. Here, the frequency transformation is used to determine the stress frequencies at high RF power levels from low-power S-parameter measurements. PMID:20040405

Wunnicke, Olaf; van der Wel, Paul J; Strijbos, Remco C; de Bruijn, Frank

2009-12-01

244

Interpreting a Dynamic and Uncertain World: High-Level Vision  

Microsoft Academic Search

When interpreting a dynamic and uncertain world it is important to have a high-level vision component that can guide the reasoning of the whole vision system. This guidance is provided by an attentional mechanism that exploits knowledge of the specific problem being solved. Here we survey work relevant to the development of such an attentional mechanism, using surveillance as an

Richard J. Howarth

1995-01-01

245

Extremely high urine arsenic level after remote seafood ingestion.  

PubMed

Urine testing for heavy metal concentrations is increasingly performed in the outpatient setting as a part of laboratory evaluation for neuropathy. Abnormal urine arsenic levels due to dietary intake of organic arsenic can lead to unnecessary chelation therapy. A 54-year-old man underwent a 24-hour urine collection for heavy metal concentrations in evaluation of paresthesia of the right foot. The total arsenic level was 8880 ?g/d with concentrations of 4749 ?g/L and 3769 ?g/g creatinine. He was urgently referred to the toxicology clinic for consideration of chelation therapy. History revealed consumption of 2 lobster tails 5 days before the testing. Speciation was then performed on the original urine specimen and revealed an organic arsenic concentration of 4332 ?g/L. No inorganic or methylated arsenic was detected. Repeat testing after abstaining from seafood demonstrated a total arsenic level of 50 ?g/d with concentrations of 30 ?g/L and 21 ?g/g creatinine. Our patient demonstrates the highest level of arsenobetaine reported in the literature, and this level is higher than expected for a person who had not consumed seafood for 5 days before testing. The high levels may be due to consumption of food that he did not recognize as containing arsenobetaine or that his clearance of arsenobetaine from the ingested lobster is slower than published ranges. This case demonstrates the importance of speciation when measuring urine arsenic levels to avoid unnecessary chelation therapy. PMID:22407195

Nañagas, Kristine A; Tormoehlen, Laura M

2014-01-01

246

The effects of winds and atmospheric structure on long-range gravity wave propagation at high latitudes  

NASA Astrophysics Data System (ADS)

Recent studies of waves over Halley, Antarctica by Nielsen et al. [JASTP, 71,8 2009; JGR, 117, D5, 2012] suggest that gravity waves at high latitude sites are less likely to exhibit narrow ducting in the mesosphere and lower thermosphere (MLT) region than at mid-to-low latitude sites, and thus may be less likely to travel large horizontal distances. These studies estimate that 82% of the wave events are freely propagating (not ducted), when compared to ~25% in some mid/low-latitude studies [Isler et al., JGR, 102, D22, 1997]. This is due to relatively weak meridional winds at high latitudes, which are typically not strong enough to provide a Doppler ducted environment. However, thermal reflection of gravity waves may still occur in the lower thermosphere, which may lead to deep non-ideal thermal ducting between the thermosphere and ground, providing another mechanism for long range propagation that would not necessarily be identifiable in measurements at OH airglow heights. In general, the horizontal propagation of gravity waves is highly dependent on the wave parameters and background atmosphere/wind structure. This complex interaction will determine dissipation processes, propagation trajectories, packet spatial extents and spectral evolutions, among other things. We use a 2D, nonlinear, compressible model [e.g., Snively et al., JGR, 113, A06303, 2008] to study specific cases of long-range propagation of atmospheric gravity waves in high-latitude atmospheric conditions, and a 1D steady-state compressible full-wave model [e.g., Hickey et al., JGR, 102, A6 1997] to study effects of varying atmospheric parameters. We investigate possible conditions which are (or are not) conducive to sustained propagation via reflections, and how these conditions may vary in space or time. Background temperature and wind structure are specified to represent profiles over Halley, Antarctica, in order to compare with observations at the same location and to assess the effects of ambient atmospheric structure and dynamics on the long-range propagation of waves. We find in particular that the thermospheric winds can facilitate strong reflection or filtering effects depending on wave propagation direction at high latitudes, and that the dissipation height relative to the reflection height determines whether a wave is likely to sustain its amplitude over large horizontal distances.

Heale, C. J.; Snively, J. B.; Hickey, M. P.

2013-12-01

247

Long-term high-level waste technology  

NASA Astrophysics Data System (ADS)

This series of reports summarizes research and development studies on the immobilization of high level wastes from the chemical reprocessing of nuclear reactor fuels. Immobilization of the wastes (defense and commercial) consists of placing them in a high integrity form with a very low potential for radionuclide release. Immobilization of commercial wastes is being considered on a contingency basis in the event that reprocessing is resumed. The basic plan for meeting the goal of immobilization of the DOE high level wastes is: (1) to develop technology to support a realistic choice of waste form alternatives for each of the three DOE sites; (2) to develop product and processing technology with sufficient scaleup to provide design data for full scale facilities; and (3) to construct and operate the facilities.

Cornman, W. R.

1980-07-01

248

Estimating gravity wave parameters from oblique high-frequency backscatter: Modeling and analysis  

SciTech Connect

A new technique for estimating electron density perturbation amplitudes of traveling ionospheric disturbances (TIDs), using HF radar data, is presented. TIDs are observed in HF radar data as enhancements of the ground-scattered power which propagate through the radar`s field of view. These TIDs are the ionospheric manifestation of atmospheric acoustic-gravity waves. TID electron density perturbation amplitudes were estimated by simulating the radar returns, using HF ray tracing through a model ionosphere perturbed by a model gravity wave. The simulation determined the return power in the ground-scattered portion of the signal as a function of range, and this was compared to HF radar data from the Goose Bay HF radar at a time when evidence of gravity waves was present in the data. By varying the amplitude of the electron density perturbation in the model it was possible to estimate the perturbation of the actual wave. It was found that the perturbations that are observed by the Goose Bay HF radar are of the order of 20% to 35%. It was also found that the number of observable power enhancements, and the relative amplitudes of these enhancements, depended on the vertical thickness of the gravity wave`s source region. From the simulations and observations it was estimated that the source region for the case presented here was approximately 20 km thick. In addition, the energy in the wave packet was calculated and compared to an estimate of the available energy in the source region. It was found that the wave energy was about 0.2% of the estimated available source region energy. 20 refs., 12 figs.

Bristow, W.A.; Greenwald, R.A. [Johns Hopkins Univ., Laurel, MD (United States)] [Johns Hopkins Univ., Laurel, MD (United States)

1995-03-01

249

Optogalvanic detection of barium high-lying levels with a two-step pulsed laser excitation  

E-print Network

L-513 Optogalvanic detection of barium high-lying levels with a two-step pulsed laser excitation P barium have been investigated by using a two-step pulsed laser excitation combined with an optogalvanic number for the ground state. In barium the ground level has a J = 0 value, so with a two- photon process

Boyer, Edmond

250

Point stability at shallow depths: experience from tilt measurements in the Lower Rhine Embayment, Germany, and implications for high-resolution GPS and gravity recordings  

NASA Astrophysics Data System (ADS)

From 1996 to 1999, we have studied ground tilts at depths of between 2m and 5m at three sites in the Lower Rhine Embayment (LRE), western Germany. The LRE is a tectonically active extensional sedimentary basin roughly 50km×100km. The purpose of the tilt measurements was (a) to provide insight into the magnitude, nature and variability of background tilts and (b) to assess possible limitations of high-resolution GPS campaigns and microgravity surveys due to natural ground deformation. The tilt readings, sensed by biaxial borehole tiltmeters of baselength 0.85m, cover a frequency range from 10-8Hz to 10-2Hz (periods from minutes to years). Assuming that the tilt signals represent ground displacements on a scale typically not larger than several times the tiltmeters' baselength, and that tilt signals at shallow depth could in a simple geometric way be related to changes in surface elevation and gravity, we try to estimate the magnitude level of point movements and corresponding Bouguer gravity effects that is generally not surpassed. The largest tilt signals observed were some +/-50µradyr-1. If they were observable over a ground section of extension, e.g. 10m, the converted rates may correspond to about +/-0.5mm per 10myr-1 in vertical ground displacement, and +/-0.1µgalyr-1 in Bouguer gravity effect, respectively. Large signals are mostly related to seasonal effects, probably linked to thermomechanical strain. Other causes of ground deformation identified include seepage effects after rainfalls (order of +/-10µrad) and diurnal strains due to thermal heating and/or fluctuations in the water consumption of nearby trees (order of +/-1µrad). Episodic step-like tilt anomalies with amplitudes up to 22µrad at one of the observation sites might reflect creep events associated to a nearby active fault. Except for short-term ground deformation caused by the passage of seismic waves from distant earthquakes, amplitudes of non-identified tilt signals in the studied frequency range seem not to exceed +/-2µrad. As the larger tilt signals are close to the precision achieved with modern GPS systems and superconducting gravimeters when converted into height and gravity changes, further enhancement in resolution of these techniques may require simultaneous recording of local ground deformation at the observation sites.

Kümpel, H.-J.; Lehmann, K.; Fabian, M.; Mentes, Gy.

2001-09-01

251

Proof of concept and performance optimization of high gravity batch-type centrifugal dryer for dewatering fine coal  

SciTech Connect

The primary objective of the project was to assemble, analyze and make use of those data that could help to clearly identify, optimize and confirm the technical and economic advantages that the new high gravity centrifugal dryer technology can provide to the coal industry and to end users. Other objectives were: to confirm the feasibility of the dryer for drying coals from a number of different seams; to use the data base for optimizing the dryer's systems, and: to produce projected technical and economic comparisons with thermal dryers as applied to an existing coal processing plant flow sheet. (JL)

Smith, L.B.; Durney, T.

1991-01-01

252

Electrochemical energy storage by polyaniline nanofibers: high gravity assisted oxidative polymerization vs. rapid mixing chemical oxidative polymerization.  

PubMed

Polyaniline (PANI) nanofibers prepared by high gravity chemical oxidative polymerization in a rotating packed bed (RPB) have demonstrated a much higher specific capacitance of 667.6 F g(-1) than 375.9 F g(-1) of the nanofibers produced by a stirred tank reactor (STR) at a gravimetric current of 10 A g(-1). Meanwhile, the cycling stability of the electrode is 62.2 and 65.9% for the nanofibers from RPB and STR after 500 cycles, respectively. PMID:25431883

Zhao, Yibo; Wei, Huige; Arowo, Moses; Yan, Xingru; Wu, Wei; Chen, Jianfeng; Wang, Yiran; Guo, Zhanhu

2015-01-14

253

High-accurate optical fiber liquid level sensor  

NASA Astrophysics Data System (ADS)

A highly accurate optical fiber liquid level sensor is presented. The single-chip microcomputer is used to process and control the signal. This kind of sensor is characterized by self-security and is explosion-proof, so it can be applied in any liquid level detecting areas, especially in the oil and chemical industries. The theories and experiments about how to improve the measurement accuracy are described. The relative error for detecting the measurement range 10 m is up to 0.01%.

Sun, Dexing; Chen, Shouliu; Pan, Chao; Jin, Henghuan

1991-08-01

254

Selection from Industrial Lager Yeast Strains of Variants with Improved Fermentation Performance in Very-High-Gravity Worts?  

PubMed Central

There are economic and other advantages if the fermentable sugar concentration in industrial brewery fermentations can be increased from that of currently used high-gravity (ca. 14 to 17°P [degrees Plato]) worts into the very-high-gravity (VHG; 18 to 25°P) range. Many industrial strains of brewer's yeast perform poorly in VHG worts, exhibiting decreased growth, slow and incomplete fermentations, and low viability of the yeast cropped for recycling into subsequent fermentations. A new and efficient method for selecting variant cells with improved performance in VHG worts is described. In this new method, mutagenized industrial yeast was put through a VHG wort fermentation and then incubated anaerobically in the resulting beer while maintaining the ?-glucoside concentration at about 10 to 20 g·liter?1 by slowly feeding the yeast maltose or maltotriose until most of the cells had died. When survival rates fell to 1 to 10 cells per 106 original cells, a high proportion (up to 30%) of survivors fermented VHG worts 10 to 30% faster and more completely (residual sugars lower by 2 to 8 g·liter?1) than the parent strains, but the sedimentation behavior and profiles of yeast-derived flavor compounds of the survivors were similar to those of the parent strains. PMID:20081007

Huuskonen, Anne; Markkula, Tuomas; Vidgren, Virve; Lima, Luis; Mulder, Linda; Geurts, Wim; Walsh, Michael; Londesborough, John

2010-01-01

255

Increased expression of the yeast multidrug resistance ABC transporter Pdr18 leads to increased ethanol tolerance and ethanol production in high gravity alcoholic fermentation  

PubMed Central

Background The understanding of the molecular basis of yeast tolerance to ethanol may guide the design of rational strategies to increase process performance in industrial alcoholic fermentations. A set of 21 genes encoding multidrug transporters from the ATP-Binding Cassette (ABC) Superfamily and Major Facilitator Superfamily (MFS) in S. cerevisiae were scrutinized for a role in ethanol stress resistance. Results A yeast multidrug resistance ABC transporter encoded by the PDR18 gene, proposed to play a role in the incorporation of ergosterol in the yeast plasma membrane, was found to confer resistance to growth inhibitory concentrations of ethanol. PDR18 expression was seen to contribute to decreased 3?H-ethanol intracellular concentrations and decreased plasma membrane permeabilization of yeast cells challenged with inhibitory ethanol concentrations. Given the increased tolerance to ethanol of cells expressing PDR18, the final concentration of ethanol produced during high gravity alcoholic fermentation by yeast cells devoid of PDR18 was lower than the final ethanol concentration produced by the corresponding parental strain. Moreover, an engineered yeast strain in which the PDR18 promoter was replaced in the genome by the stronger PDR5 promoter, leading to increased PDR18 mRNA levels during alcoholic fermentation, was able to attain a 6?% higher ethanol concentration and a 17?% higher ethanol production yield than the parental strain. The improved fermentative performance of yeast cells over-expressing PDR18 was found to correlate with their increased ethanol tolerance and ability to restrain plasma membrane permeabilization induced throughout high gravity fermentation. Conclusions PDR18 gene over-expression increases yeast ethanol tolerance and fermentation performance leading to the production of highly inhibitory concentrations of ethanol. PDR18 overexpression in industrial yeast strains appears to be a promising approach to improve alcoholic fermentation performance for sustainable bio-ethanol production. PMID:22839110

2012-01-01

256

High-level waste management technology program plan  

SciTech Connect

The purpose of this plan is to document the integrated technology program plan for the Savannah River Site (SRS) High-Level Waste (HLW) Management System. The mission of the SRS HLW System is to receive and store SRS high-level wastes in a see and environmentally sound, and to convert these wastes into forms suitable for final disposal. These final disposal forms are borosilicate glass to be sent to the Federal Repository, Saltstone grout to be disposed of on site, and treated waste water to be released to the environment via a permitted outfall. Thus, the technology development activities described herein are those activities required to enable successful accomplishment of this mission. The technology program is based on specific needs of the SRS HLW System and organized following the systems engineering level 3 functions. Technology needs for each level 3 function are listed as reference, enhancements, and alternatives. Finally, FY-95 funding, deliverables, and schedules are s in Chapter IV with details on the specific tasks that are funded in FY-95 provided in Appendix A. The information in this report represents the vision of activities as defined at the beginning of the fiscal year. Depending on emergent issues, funding changes, and other factors, programs and milestones may be adjusted during the fiscal year. The FY-95 SRS HLW technology program strongly emphasizes startup support for the Defense Waste Processing Facility and In-Tank Precipitation. Closure of technical issues associated with these operations has been given highest priority. Consequently, efforts on longer term enhancements and alternatives are receiving minimal funding. However, High-Level Waste Management is committed to participation in the national Radioactive Waste Tank Remediation Technology Focus Area. 4 refs., 5 figs., 9 tabs.

Harmon, H.D.

1995-01-01

257

RETENTION OF SULFATE IN HIGH LEVEL RADIOACTIVE WASTE GLASS  

SciTech Connect

High level radioactive wastes are being vitrified at the Savannah River Site for long term disposal. Many of the wastes contain sulfate at concentrations that can be difficult to retain in borosilicate glass. This study involves efforts to optimize the composition of a glass frit for combination with the waste to improve sulfate retention while meeting other process and product performance constraints. The fabrication and characterization of several series of simulated waste glasses are described. The experiments are detailed chronologically, to provide insight into part of the engineering studies used in developing frit compositions for an operating high level waste vitrification facility. The results lead to the recommendation of a specific frit composition and a concentration limit for sulfate in the glass for the next batch of sludge to be processed at Savannah River.

Fox, K.

2010-09-07

258

Hierarchical trapping of resonance states at high level density  

SciTech Connect

On the basis of a simple [ital S]-matrix model we show that, at high average level density, local fluctuations in the density of states of an open quantum mechanical system create locally a few broad resonance states together with a larger number of narrow (trapped) ones. The widths of the broad states are of the order of the length which characterizes the local fluctuations in the spectrum. They serve as a background for the narrow fine-structure resonances.'' If the spectrum shows a hierarchical fluctuation pattern in energy, this behavior repeats on all energy scales. From these results, we conjecture that the well-known intermediate structures in nuclei at high level density, described by the doorway mechanism, are formed due to such a trapping effect.

Iskra, W.; Rotter, I.; Dittes, F. (FZ Rossendorf, Institut fuer Kern- und Hadronenphysik, O-8051 Dresden (Germany))

1993-03-01

259

Life Extension of Aging High-Level Waste Tanks  

SciTech Connect

The Double Shell Tanks (DSTs) play a critical role in the Hanford High-Level Waste Treatment Complex, and therefore activities are underway to protect and better understand these tanks. The DST Life Extension Program is focused on both tank life extension and on evaluation of tank integrity. Tank life extension activities focus on understanding tank failure modes and have produced key chemistry and operations controls to minimize tank corrosion and extend useful tank life. Tank integrity program activities have developed and applied key technologies to evaluate the condition of the tank structure and predict useful tank life. Program results to date indicate that DST useful life can be extended well beyond the original design life and allow the existing tanks to fill a critical function within the Hanford High-Level Waste Treatment Complex. In addition the tank life may now be more reliably predicted, facilitating improved planning for the use and possible future replacement of these tanks.

Bryson, D.; Callahan, V.; Ostrom, M.; Bryan, W.; Berman, H.

2002-02-26

260

Evaluation and selection of candidate high-level waste forms  

SciTech Connect

Seven candidate waste forms being developed under the direction of the Department of Energy's National High-Level Waste (HLW) Technology Program, were evaluated as potential media for the immobilization and geologic disposal of high-level nuclear wastes. The evaluation combined preliminary waste form evaluations conducted at DOE defense waste-sites and independent laboratories, peer review assessments, a product performance evaluation, and a processability analysis. Based on the combined results of these four inputs, two of the seven forms, borosilicate glass and a titanate based ceramic, SYNROC, were selected as the reference and alternative forms for continued development and evaluation in the National HLW Program. Both the glass and ceramic forms are viable candidates for use at each of the DOE defense waste-sites; they are also potential candidates for immobilization of commercial reprocessing wastes. This report describes the waste form screening process, and discusses each of the four major inputs considered in the selection of the two forms.

Bernadzikowski, T. A.; Allender, J. S.; Butler, J. L.; Gordon, D. E.; Gould, Jr., T. H.; Stone, J. A.

1982-03-01

261

High Level Information Fusion (HLIF) with nested fusion loops  

NASA Astrophysics Data System (ADS)

Situation modeling and threat prediction require higher levels of data fusion in order to provide actionable information. Beyond the sensor data and sources the analyst has access to, the use of out-sourced and re-sourced data is becoming common. Through the years, some common frameworks have emerged for dealing with information fusion—perhaps the most ubiquitous being the JDL Data Fusion Group and their initial 4-level data fusion model. Since these initial developments, numerous models of information fusion have emerged, hoping to better capture the human-centric process of data analyses within a machine-centric framework. 21st Century Systems, Inc. has developed Fusion with Uncertainty Reasoning using Nested Assessment Characterizer Elements (FURNACE) to address challenges of high level information fusion and handle bias, ambiguity, and uncertainty (BAU) for Situation Modeling, Threat Modeling, and Threat Prediction. It combines JDL fusion levels with nested fusion loops and state-of-the-art data reasoning. Initial research has shown that FURNACE is able to reduce BAU and improve the fusion process by allowing high level information fusion (HLIF) to affect lower levels without the double counting of information or other biasing issues. The initial FURNACE project was focused on the underlying algorithms to produce a fusion system able to handle BAU and repurposed data in a cohesive manner. FURNACE supports analyst's efforts to develop situation models, threat models, and threat predictions to increase situational awareness of the battlespace. FURNACE will not only revolutionize the military intelligence realm, but also benefit the larger homeland defense, law enforcement, and business intelligence markets.

Woodley, Robert; Gosnell, Michael; Fischer, Amber

2013-05-01

262

Sound absorption of porous metals at high sound pressure levels.  

PubMed

This paper is a study about sound absorption properties of porous metals at high sound pressure levels. A method of deriving the nonlinear static flow resistance for highly porous fibrous metals is proposed by solving Oseen's equation to take account of the inertia effect, validated by experiments of airflow measurement. In order to predict nonlinear sound absorbing performance of a finite thickness porous metal layer, a numerical method is employed, verified by sound absorption measurement in an impedance tube. Accordingly, the effects of the nonlinear coefficient on the porous metal sound absorption are investigated. PMID:19640016

Wang, Xiaolin; Peng, Feng; Chang, Baojun

2009-08-01

263

Network congestion analysis of gravity generated models  

NASA Astrophysics Data System (ADS)

The network topology has lately proved to be critical to the appearance of traffic congestion, with scale-free networks being the less affected at high volumes of traffic. Here, the congestion dynamics are investigated for a class of networks that has experienced a resurgence of interest, the networks based on the gravity model. In addition, supplementary to the standard paradigm of uniform traffic volumes between randomly interacting node pairs, more realistic gravity traffic patterns are used to simulate the flows in the network. Results indicate that depending on the traffic pattern, the networks have different tolerance to congestion. Experiment simulation shows that the topologies created on the basis of the gravity model suffer less from congestion than the random, the scale-free or the Jackson-Rogers ones under both random and gravity traffic patterns. The congestion level is found to be approximately correlated with the network clustering coefficient in the case of random traffic, whereas in the case of gravity traffic such a correlation is not a trivial one. Other basic network properties such as the average shortest path and the diameter are seen to correlate fairly well with the congestion level. Further investigation on the adjustment of the gravity model parameters indicates particular sensitivity to network congestion. This work may have practical implications for designing traffic networks with both reasonable budget and good performance.

Maniadakis, Dimitris; Varoutas, Dimitris

2014-07-01

264

FLUIDIZED BED STEAM REFORMING ENABLING ORGANIC HIGH LEVEL WASTE DISPOSAL  

SciTech Connect

Waste streams planned for generation by the Global Nuclear Energy Partnership (GNEP) and existing radioactive High Level Waste (HLW) streams containing organic compounds such as the Tank 48H waste stream at Savannah River Site have completed simulant and radioactive testing, respectfully, by Savannah River National Laboratory (SRNL). GNEP waste streams will include up to 53 wt% organic compounds and nitrates up to 56 wt%. Decomposition of high nitrate streams requires reducing conditions, e.g. provided by organic additives such as sugar or coal, to reduce NOX in the off-gas to N2 to meet Clean Air Act (CAA) standards during processing. Thus, organics will be present during the waste form stabilization process regardless of the GNEP processes utilized and exists in some of the high level radioactive waste tanks at Savannah River Site and Hanford Tank Farms, e.g. organics in the feed or organics used for nitrate destruction. Waste streams containing high organic concentrations cannot be stabilized with the existing HLW Best Developed Available Technology (BDAT) which is HLW vitrification (HLVIT) unless the organics are removed by pretreatment. The alternative waste stabilization pretreatment process of Fluidized Bed Steam Reforming (FBSR) operates at moderate temperatures (650-750 C) compared to vitrification (1150-1300 C). The FBSR process has been demonstrated on GNEP simulated waste and radioactive waste containing high organics from Tank 48H to convert organics to CAA compliant gases, create no secondary liquid waste streams and create a stable mineral waste form.

Williams, M

2008-05-09

265

Automatic rule generation for high-level vision  

NASA Technical Reports Server (NTRS)

Many high-level vision systems use rule-based approaches to solving problems such as autonomous navigation and image understanding. The rules are usually elaborated by experts. However, this procedure may be rather tedious. In this paper, we propose a method to generate such rules automatically from training data. The proposed method is also capable of filtering out irrelevant features and criteria from the rules.

Rhee, Frank Chung-Hoon; Krishnapuram, Raghu

1992-01-01

266

Expectation Grammars: Leveraging High-Level Expectations for Activity Recognition  

Microsoft Academic Search

Video-based recognition and prediction of a temporally ex- tended activity can benefit from a detailed description of high-level expectations about the activity. Stochastic gr am- mars allow for an efficient representation of such expecta- tions and are well-suited for the specification of temporall y well-ordered activities. In this paper, we extend stochast ic grammars by adding event parameters, state checks,

David Minnen; Irfan A. Essa; Thad Starner

2003-01-01

267

Case for retrievable high-level nuclear waste disposal  

USGS Publications Warehouse

Plans for the nation's first high-level nuclear waste repository have called for permanently closing and sealing the repository soon after it is filled. However, the hydrologic environment of the proposed site at Yucca Mountain, Nevada, should allow the repository to be kept open and the waste retrievable indefinitely. This would allow direct monitoring of the repository and maintain the options for future generations to improve upon the disposal methods or use the uranium in the spent fuel as an energy resource.

Roseboom, Eugene H., Jr.

1994-01-01

268

Mixing Processes in High-Level Waste Tanks - Final Report  

SciTech Connect

The mixing processes in large, complex enclosures using one-dimensional differential equations, with transport in free and wall jets is modeled using standard integral techniques. With this goal in mind, we have constructed a simple, computationally efficient numerical tool, the Berkeley Mechanistic Mixing Model, which can be used to predict the transient evolution of fuel and oxygen concentrations in DOE high-level waste tanks following loss of ventilation, and validate the model against a series of experiments.

Peterson, P.F.

1999-05-24

269

Deep borehole disposal of high-level radioactive waste  

Microsoft Academic Search

Preliminary evaluation of deep borehole disposal of high-level radioactive waste and spent nuclear fuel indicates the potential for excellent long-term safety performance at costs competitive with mined repositories. Significant fluid flow through basement rock is prevented, in part, by low permeabilities, poorly connected transport pathways, and overburden self-sealing. Deep fluids also resist vertical movement because they are density stratified. Thermal

Joshua S. Stein; Geoffrey A. Freeze; Patrick Vane Brady; Peter N. Swift; Robert Paul Rechard; Bill Walter Arnold; Joseph F. Kanney; Stephen J. Bauer

2009-01-01

270

Security Mechanisms in High-Level Network Protocols  

Microsoft Academic Search

The implications of adding security mechanisms to high-level network protocols operating in an open-system environment are analyzed. First the threats to security that may arise in such an environment are described, and then a set of goals for communications security measures is established. This is followed by a brief description of the two basic approaches to communications security, link-oriented measures

Victor L. Voydock; Stephen T. Kent

1983-01-01

271

High Level System Design and Analysis Using Abstract State Machines  

Microsoft Academic Search

We provide an introduction to a practical method for rigorous system development which has been used successfully, under industrial\\u000a constraints, for design and analysis of complex hardware\\/software systems. The method allows one to start system development\\u000a with a trustworthy high level system specification and to link such a “ground model” in a well documented and inspectable\\u000a way through intermediate design

Egon Börger

1998-01-01

272

Tethered gravity laboratories study  

NASA Technical Reports Server (NTRS)

Variable Gravity Laboratory studies are discussed. The following subject areas are covered: (1) conceptual design and engineering analysis; (2) control strategies (fast crawling maneuvers, main perturbations and their effect upon the acceleration level); and (3) technology requirements.

Lucchetti, F.

1989-01-01

273

Handbook of high-level radioactive waste transportation  

SciTech Connect

The High-Level Radioactive Waste Transportation Handbook serves as a reference to which state officials and members of the general public may turn for information on radioactive waste transportation and on the federal government`s system for transporting this waste under the Civilian Radioactive Waste Management Program. The Handbook condenses and updates information contained in the Midwestern High-Level Radioactive Waste Transportation Primer. It is intended primarily to assist legislators who, in the future, may be called upon to enact legislation pertaining to the transportation of radioactive waste through their jurisdictions. The Handbook is divided into two sections. The first section places the federal government`s program for transporting radioactive waste in context. It provides background information on nuclear waste production in the United States and traces the emergence of federal policy for disposing of radioactive waste. The second section covers the history of radioactive waste transportation; summarizes major pieces of legislation pertaining to the transportation of radioactive waste; and provides an overview of the radioactive waste transportation program developed by the US Department of Energy (DOE). To supplement this information, a summary of pertinent federal and state legislation and a glossary of terms are included as appendices, as is a list of publications produced by the Midwestern Office of The Council of State Governments (CSG-MW) as part of the Midwestern High-Level Radioactive Waste Transportation Project.

Sattler, L.R.

1992-10-01

274

High Resolution Magnetic and Gravity Surveys to Constrain Maar Geometry and Eruption Mechanisms, Rattlesnake Crater, Arizona  

NASA Astrophysics Data System (ADS)

Located 25 kilometers east of Flagstaff, Arizona, Rattlesnake Crater is an oblong phreatomagmatic feature in the San Francisco Volcanic Field. The shallow crater is approximately 1.4 kilometers at its widest point, and surrounded by an uneven tuff ring which is overlapped by a scoria cone volcano on the southeastern side. Improved understanding of its formation and evolution requires geophysical study because there are very few outcrops, and no digging is permitted on site. Geologic features related to the crater are further obscured by deposits from the overlapping scoria cone, as well as tephra from eruptions at nearby Sunset Crater. We present the results of a detailed magnetic and gravity survey in and around Rattlesnake Crater. A substantial NW-SE trending elongate magnetic anomaly (1400 nT) and a smaller similarly trending anomaly are observed inside the crater, as well as a longer wavelength positive gravitational anomaly (+1.0-1.5 mGal) across the crater. The magnetic survey was completed on foot with a 50 meter line spacing inside the crater, and 100 meter line spacing across a portion of the surrounding area outside the crater. The gravity survey was done on two intersecting survey lines - one running west to east, and another roughly north to south, with recordings every 100 meters extending at least 1000 meters outside the crater in all four directions. 2D models of the magnetic and gravity data are presented illustrating the possible geometry of the diatreme, and the approximate size and shape of the major intrusive features. Eruption estimates based on the models are calculated, and the models are favorably compared to the size and depth estimates given in a recent publication (Valentine 2012) that used xenolith content to estimate the size and depth of the diatreme.

Marshall, A. M.; Kruse, S. E.; Connor, C.; Connor, L.; Abdollahzadeh, M.; Harburger, A.; Richardson, J. A.; Courtland, L. M.; Farrell, A. K.; Kiflu, H. G.; Malservisi, R.; McNiff, C. M.; Njoroge, M.; Nushart, N.; Rookey, K.

2013-12-01

275

The muon high level trigger of the ATLAS experiment  

NASA Astrophysics Data System (ADS)

The ATLAS experiment at CERN's Large Hadron Collider (LHC) has been designed and built for new discoveries in High Energy Physics as well as for precision measurements of Standard Model parameters. To satisfy the limited data acquisition and recording capability, at the LHC project luminosity, the ATLAS trigger system must select a very small rate of physically interesting events (~200 Hz) among about 40 million events per second. In the case of events containing muons, as described in this work, the first hardware-based level (Level-1) starts from coincidence of hits in the Muon Spectrometer trigger chambers to select Regions of Interest (RoI) where muons produce significant activity. Such RoIs are used as seeds for the two subsequent trigger levels (Level-2 and Event Filter), running on dedicated online farms, which constitute the High Level Trigger (HLT). This seeding strategy is crucial to drastically reduce the total processing time. Within the Muon HLT, few algorithms are implemented in different steps according to predefined sequences of Feature Extraction (FEX) and Hypothesis (HYPO) algorithms, whose goal is to validate the previously selected muon objects. The ATLAS muon trigger system, thanks to its particular design and to the peculiar structure of the Muon Spectrometer, is able to provide muon stand-alone event trigger decisions, that can be furtherly refined by exploiting the muon information coming from the other ATLAS subdetectors. Muon HLT algorithms are described here in terms of working functionality and performance both on simulated and real data, including non-standard trigger configurations (like cosmic data and LHC start-up scenarios).

Ventura, Andrea; ATLAS Collaboration

2010-04-01

276

High-level gene transfer to the cornea using electroporation  

PubMed Central

Background Methods for gene transfer to the cornea that yield high-level expression without inflammation or trauma are currently lacking. Because electroporation has proven effective for gene transfer in other tissues in terms of expression levels and safety, this study quantitatively evaluated its use in the cornea. Methods To evaluate the use of electroporation in the mouse cornea, plasmids expressing either luciferase or green fluorescent protein were injected intracorneally or subconjunctivally and square-wave electric pulses were immediately applied to the eyes. Gene expression was quantified at later times and trauma and inflammation were monitored visually and by measuring interleukin-6 (IL-6) production. Results The application of electric pulses to eyes injected with plasmid resulted in nanogram levels of gene product expression. At an optimal field strength of 200 V/cm, no trauma, corneal edema or inflammation was observed. However, at higher field strengths, corneal damage was detected. Compared with injection of DNA alone, up to 1000-fold more gene product was produced using electroporation. Expression was detected as early as 6 h post-electroporation, remained high for 3 days, and decreased by 7 days. Gene expression was detected over the entire surface of the cornea in both epithelial and stromal layers. Conclusions These results demonstrate that electroporation is an excellent method for delivering genes to multiple cell layers within the mouse cornea and that it results in extremely high levels of gene expression with little, if any, inflammatory response or tissue damage, making this a very useful technique for corneal gene transfer. PMID:11828392

Blair-Parks, Kathleen; Weston, Bonnie C.; Dean, David A.

2015-01-01

277

Exceptionally high levels of multiple mating in an army ant  

NASA Astrophysics Data System (ADS)

Most species of social insects have singly mated queens, although there are notable exceptions. Competing hypotheses have been proposed to explain the evolution of high levels of multiple mating, but this issue is far from resolved. Here we use microsatellites to investigate mating frequency in the army ant Eciton burchellii and show that queens mate with an exceptionally large number of males, eclipsing all but one other social insect species for which data are available. In addition we present evidence that suggests that mating is serial, continuing throughout the lifetime of the queen. This is the first demonstration of serial mating among social hymenoptera. We propose that high paternity within colonies is most likely to have evolved to increase genetic diversity and to counter high pathogen and parasite loads.

Denny, A. Jay; Franks, Nigel R.; Powell, Scott; Edwards, Keith J.

278

ALICE: Project Overview and High Level Science Products  

NASA Astrophysics Data System (ADS)

We report on the status of the ALICE project (Archival Legacy Investigation of Circumstellar Environments), which consists in a consistent reanalysis of the entire HST-NICMOS coronagraphic archive. Over the last two years, we have developed a sophisticated pipeline able to handle the data of the 400 stars of the archive. This pipeline builds on the Karhunen-Loeve Image Projection (KLIP) algorithm, and was completed in the fall of 2014. We discuss the first processing and analysis results of the overall reduction campaign. As we will deliver high-level science products to the STScI MAST archive, we are defining a new standard format for high-contrast science products, which will be compatible with every new high-contrast imaging instrument (GPI, SPHERE, P1640, CHARIS, etc.) and used by the JWST coronagraphs. We present here the specifications of this standard.

Soummer, Remi; Choquet, Elodie; Pueyo, Laurent; Brendan Hagan, J.; Gofas-Salas, Elena; Rajan, Abhijith; Perrin, Marshall D.; Chen, Christine; Debes, John H.; Golimowski, David A.; Hines, Dean C.; Schneider, Glenn; N'Diaye, Mamadou; Mawet, Dimitri; Marois, Christian; Barman, Travis

2015-01-01

279

Hot water and dilute acid pretreatment of high and low specific gravity Populus deltoides clones.  

PubMed

Populus sp. are hardwood feedstocks that grow in forest management areas that are logged for softwoods; however, they are also being considered as an energy-destined feedstock. The objective of this work was to determine the effect of xylose yield from dilute acid and hot water pretreatments performed in unstirred batch stainless steel reactors at temperatures ranging from 140 to 200°C. Populus deltoides clones S13C20 and S7C15 used in this study originated from Eastern Texas and were cultivated for 14 years in Pine Tree, AR. P. deltoides clones S13C20 and S7C15 had specific gravities of 0.48 and 0.40, respectively. Bark and wood were examined separately. As expected, hot water pretreatments, in the tested temperature range, resulted in very little direct xylose recovery. However, the 140°C dilute acid pretreatment of the lower specific gravity clone, S7C15, wood yielded the highest average xylose recovery of 56%. This condition also yielded the highest concentration of furfural, 9 mg/g sample, which can be inhibitory to the fermentation step. The highest xylose recovery from bark samples, 31%, was obtained with clone S7C15, using the 160°C dilute acid pretreatment for 60 min. PMID:20652357

Martin, Elizabeth M; Bunnell, Kris A; Lau, Ching-Shuan; Pelkki, Matthew H; Patterson, David W; Clausen, Edgar C; Smith, James A; Carrier, Danielle Julie

2011-02-01

280

Ultrasonic level sensors for liquids under high pressure  

NASA Astrophysics Data System (ADS)

An ultrasonic level sensor of novel design continuously measures the level of a liquid subjected to a high pressure (up to about 40 MPa), as is sometimes required for the effective transfer of the liquid. The sensor operates as a composite resonator fabricated from a standard high-pressure plug. A flat-bottom hole is machined into the plug along its center line. An ultrasonic transducer is bonded rigidly to the interior surface of the bottom wall, while the exterior surface is in contact with the liquid. Although the bottom wall is designed to satisfy the pressure code, it is still sufficiently thin to permit ready excitation of the axisymmetric plate modes of vibration. The liquid level is measured by a conventional pulse-echo technique. A prototype sensor was tested successfully in a 2300-l water vessel at pressures up to about 37 MPa. A spectral analysis of the transmitted pulse reveals that the flexural, extensional, thickness-shear, and radial plate modes are excited into vibration, but none of these appears to be significantly affected by the pressurization of the liquid.

Zuckerwar, A. J.; Mazel, D. S.; Hodges, D. Y.

1986-09-01

281

Ultrasonic level sensors for liquids under high pressure  

NASA Technical Reports Server (NTRS)

An ultrasonic level sensor of novel design continuously measures the level of a liquid subjected to a high pressure (up to about 40 MPa), as is sometimes required for the effective transfer of the liquid. The sensor operates as a composite resonator fabricated from a standard high-pressure plug. A flat-bottom hole is machined into the plug along its center line. An ultrasonic transducer is bonded rigidly to the interior surface of the bottom wall, while the exterior surface is in contact with the liquid. Although the bottom wall is designed to satisfy the pressure code, it is still sufficiently thin to permit ready excitation of the axisymmetric plate modes of vibration. The liquid level is measured by a conventional pulse-echo technique. A prototype sensor was tested successfully in a 2300-l water vessel at pressures up to about 37 MPa. A spectral analysis of the transmitted pulse reveals that the flexural, extensional, thickness-shear, and radial plate modes are excited into vibration, but none of these appears to be significantly affected by the pressurization of the liquid.

Zuckerwar, A. J.; Mazel, D. S.; Hodges, D. Y.

1986-01-01

282

Characterization of Transducers and Resonators under High Drive Levels  

NASA Technical Reports Server (NTRS)

In many applications, piezoelectric transducers are driven at AC voltage levels well beyond the level for which the material was nominally characterized. In this paper we describe an experimental setup that allows for the determination of the main transducer or resonator properties under large AC drive. A sinusoidal voltage from a waveform generator is amplified and applied across the transducer/resonator in series with a known high power resistor. The amplitude of applied voltage and the amplitude and the relative phase of the current through the resistor are monitored on a digital scope. The frequency of the applied signal is swept through resonance and the voltage/current signals are recorded. After corrections for the series resistance and parasitic elements the technique allows for the determination of the complex impedance spectra of the sample as a function of frequency. In addition, access to the current signal allows for the direct investigation of non-linear effects through the application of Fourier transform techniques on the current signal. Our results indicate that care is required when interpreting impedance data at high drive level due to the frequency dependence of the dissipated power. Although the transducer/resonator at a single frequency and after many cycles may reach thermal equilibrium, the spectra as a whole cannot be considered an isothermal measurement due to the temperature change with frequency. Methods to correct for this effect will be discussed. Results determined from resonators of both soft and hard PZT and a ultrasonic horn transducer are presented.

Sherrit, Stewart; Bao, X.; Sigel, D. A.; Gradziel, M. J.; Askins, S. A.; Dolgin, B. P.; Bar-Cohen, Y.

2001-01-01

283

Space augmentation of military high-level waste disposal  

NASA Technical Reports Server (NTRS)

Space disposal of selected components of military high-level waste (HLW) is considered. This disposal option offers the promise of eliminating the long-lived radionuclides in military HLW from the earth. A space mission which meets the dual requirements of long-term orbital stability and a maximum of one space shuttle launch per week over a period of 20-40 years, is a heliocentric orbit about halfway between the orbits of earth and Venus. Space disposal of high-level radioactive waste is characterized by long-term predictability and short-term uncertainties which must be reduced to acceptably low levels. For example, failure of either the Orbit Transfer Vehicle after leaving low earth orbit, or the storable propellant stage failure at perihelion would leave the nuclear waste package in an unplanned and potentially unstable orbit. Since potential earth reencounter and subsequent burn-up in the earth's atmosphere is unacceptable, a deep space rendezvous, docking, and retrieval capability must be developed.

English, T.; Lees, L.; Divita, E.

1979-01-01

284

High level language-based robotic control system  

NASA Technical Reports Server (NTRS)

This invention is a robot control system based on a high level language implementing a spatial operator algebra. There are two high level languages included within the system. At the highest level, applications programs can be written in a robot-oriented applications language including broad operators such as MOVE and GRASP. The robot-oriented applications language statements are translated into statements in the spatial operator algebra language. Programming can also take place using the spatial operator algebra language. The statements in the spatial operator algebra language from either source are then translated into machine language statements for execution by a digital control computer. The system also includes the capability of executing the control code sequences in a simulation mode before actual execution to assure proper action at execution time. The robot's environment is checked as part of the process and dynamic reconfiguration is also possible. The languages and system allow the programming and control of multiple arms and the use of inward/outward spatial recursions in which every computational step can be related to a transformation from one point in the mechanical robot to another point to name two major advantages.

Rodriguez, Guillermo (Inventor); Kreutz, Kenneth K. (Inventor); Jain, Abhinandan (Inventor)

1996-01-01

285

Evidence for adrenalin secretion regardless of high extraglandular levels.  

PubMed

Chronic adrenalin administration (4 mg/18 hrs) by means of a subcutaneous depot capsule leads to hypoglycaemia and adrenalin depletion of the suprarenal gland within 18 hrs. Stimultaneous application of glucose prevents hypoglycemia as well as adrenalin depletion. By injection of 3H-labelled tyrosine 10, 20 or 30 min before killing and subsequent detection of the quantity of labelled tyrosine and adrenalin in the sera by mixing them with a standard solution containing considerable amounts of unlabelled tyrosine and adrenalin, and by passing them through a Sephadex G-10 column and finally detecting the radioactivity of the fractions in a liquid scintillation-counter, we could prove that during the stage of hypoglycaemia an enhanced adrenalin synthesis and secretion did take place regardless of a high extraglandular level. In animals treated with adrenalin and glucose, NaCl solution or alpha-methyl-tyrosine methylester-HCl no increased resp. no turnover at all could be seen. Therefore, we conclude that there is not only a lack of a direct negative feedback system between adrenalin synthesis, secretion and extraglandular level but also that the enhanced synthesis of adrenalin that can take place in spite of a high serum level can initiate a fatel circulus vitiosus. PMID:535620

Porta, S; Englmayer, G; Kubat, R; Egger, G; Sadjak, T

1979-01-01

286

Clear and measurable signature of modified gravity in the galaxy velocity field.  

PubMed

The velocity field of dark matter and galaxies reflects the continued action of gravity throughout cosmic history. We show that the low-order moments of the pairwise velocity distribution v_{12} are a powerful diagnostic of the laws of gravity on cosmological scales. In particular, the projected line-of-sight galaxy pairwise velocity dispersion ?_{12}(r) is very sensitive to the presence of modified gravity. Using a set of high-resolution N-body simulations, we compute the pairwise velocity distribution and its projected line-of-sight dispersion for a class of modified gravity theories: the chameleon f(R) gravity and Galileon gravity (cubic and quartic). The velocities of dark matter halos with a wide range of masses would exhibit deviations from general relativity at the (5-10)? level. We examine strategies for detecting these deviations in galaxy redshift and peculiar velocity surveys. If detected, this signature would be a "smoking gun" for modified gravity. PMID:24949751

Hellwing, Wojciech A; Barreira, Alexandre; Frenk, Carlos S; Li, Baojiu; Cole, Shaun

2014-06-01

287

Exploring medium gravity icy planetary bodies: an opportunity in the Inner System by landing at Ceres high latitudes  

NASA Astrophysics Data System (ADS)

With potentially up to 25% of its mass as H2O and current indications of a differentiated morphology, 950km-wide "dwarf planet" Ceres is holding the promise to be our closest significant icy planetary body. Ceres is within easier reach than the icy moons, allowing for the use of solar arrays and not lying inside the deep gravity well of a giant planet. As such, it would represent an ideal step stone for future in-situ exploration of other airless icy bodies of major interest such as Europa or Enceladus. But when NASA's Dawn orbits Ceres and maps it in 2015, will we be ready to undertake the next logical step: landing? Ceres' gravity at its poles, at about one fifth of the Moon's gravity, is too large for rendezvous-like asteroid landing techniques to apply. Instead, we are there fully in the application domain of soft precision landing techniques such as the ones being developed for ESA's MoonNext mission. These latter require a spacecraft architecture akin to robotic lunar Landers or NASA's Phoenix, and differing from missions to comets and asteroids. If Dawn confirms the icy nature of Ceres under its regolith-covered surface, the potential presence of some ice spots on the surface would call for specific attention. Such spots would indeed be highly interesting landing sites. They are more likely to lie close to the poles of Ceres where cold temperatures should prevent exposed ice from sublimating and/or may limit the thickness of the regolith layer. Also the science and instruments suite should be fitted to study a large body that has probably been or may still be geologically active: its non-negligible gravity field combined with its high volatile mass fraction would then bring Ceres closer in morphology and history to an "Enceladus" or a frozen or near-frozen "Europa" than to a rubble-pile-structured asteroid or a comet nucleus. Thales Alenia Space and the "Laboratoire de Planétologie et Géodynamique" of the University of Nantes have carried out a preliminary assessment of a mission to Ceres high latitudes. We present here why we think an in-situ mission to the polar areas of Ceres should be of interest in the near future. We dwell on the environmental factors and challenges for a Lander, both as specificities of Ceres and as a consequence of the high latitude targeted. Factors such as day duration, fine regolith, terrain hazards, optical contrasts, thermal gradients, planetary contamination... are reviewed. We then assess how the soft precision landing technologies being developed for other missions would apply in such an environment. We present a preliminary mission analysis and a concept for the Lander, with preliminary evaluation of mass and power resources for a fixed payload or for a mini-rover. The resulting mission design combines technological maturity and a launch mass that is found compatible with the moderate cost of a Soyuz launcher. Finally we conclude that a Ceres Polar Lander mission should be feasible, covered by automatic missions to the Moon in terms of difficulty of landing and by Dawn for the cruise. Lander missions to medium gravity bodies such as Ceres, Enceladus, Europa, Ganymede, Callisto, Iapetus, Triton… in the [0.01-0.15g] range should be accounted for in the development roadmaps of landing techniques and be considered in their return on investment. The synergies with the soft landing missions to come on Mars and Moon should then make a Ceres lander affordable for the agencies within the end of the next decade and pave the way for in-situ missions to more distant icy bodies.

Poncy, J.; Grasset, O.; Martinot, V.; Tobie, G.

2009-04-01

288

Effects of particulate materials and osmoprotectants on very-high-gravity ethanolic fermentation by Saccharomyces cerevisiae.  

PubMed Central

The effects of osmoprotectants (such as glycine betaine and proline) and particulate materials on the fermentation of very high concentrations of glucose by the brewing strain Saccharomyces cerevisiae (uvarum) NCYC 1324 were studied. The yeast growing at 20 degrees C consumed only 15 g of the sugar per 100 ml from a minimal medium which initially contained 35% (wt/vol) glucose. Supplementing the medium with a mixture of glycine betaine, glycine, and proline increased the amount of sugar fermented to 30.5 g/100 ml. With such supplementation, the viability of the yeast cells was maintained above 80% throughout the fermentation, while it dropped to less than 12% in the unsupplemented controls. Among single additives, glycine was more effective than proline or glycine betaine. On incubating the cultures for 10 days, the viability decreased to only 55% with glycine, while it dropped to 36 and 27%, respectively, with glycine betaine and proline. It is suggested that glycine and proline, known to be poor nitrogen sources for growth, may serve directly or indirectly as osmoprotectants. Nutrients such as tryptone, yeast extract, and a mixture of purine and pyrimidine bases increased the sugar uptake and ethanol production but did not allow the population to maintain the high level of cell viability. While only 43% of the sugar was fermented in unsupplemented medium, the presence of particulate materials such as wheat bran, wheat mash insolubles, alumina, and soy flour increased sugar utilization to 68, 75, 81, and 82%, respectively. PMID:8017934

Thomas, K C; Hynes, S H; Ingledew, W M

1994-01-01

289

High resolution evidence for the Garrett-Munk spectrum of stratospheric gravity waves  

NASA Astrophysics Data System (ADS)

Vertical profiles of scalar horizontal winds have been measured at high resolution (10 m) in the 13 to 37 km region of the stratosphere. This resolution (at that range of altitude) represents the state-of-the-art, and is unique. The technique used smoke trails laid by rockets in the stratosphere, and were taken by AFGL at Wallops Island, VA, White Sands Missile Range, NM, and Ft. Churchill, Canada, in the 1977-78 time period. Two or three cameras were used to give the time-lapse photographs. The goal was to ascertain whether or not the internal waves of the stratosphere behave consistently with the Garrett-Munk model which was originally created for oceanic internal waves. Five profiles of horizontal wind are presented. It is concluded: (1) stratospheric internal waves obey the Garrett-Munk model for vertical wave numbers; (2) there is not statistically significant evidence for a break in the curve at high wave numbers when due allowance is made for aliasing effects; and (3) the power density level of the spectra are almost equal on a log-log scale in spite of the difference in time, season, and geographical location.

Dewan, E. M.; Grossbard, N.; Quesada, A. F.; Good, R. E.

1984-12-01

290

University-Level Research Projects for High School Students  

NASA Technical Reports Server (NTRS)

The goal of this project was to provide an opportunity for high school students to participate in university-level research projects. In this case, students from Pinkerton Academy (Derry, New Hampshire) were invited to participate in efforts to catalog data from the COMPTEL experiment on NASA's Compton Gamma-Ray Observatory (CGRO). These activities were part of a senior level honors course at Pinkerton. Although the success of this particular program was rather limited, we feel that the general concept is a sound one. In principle, the concept of partnerships between local schools and university researchers is one that could be especially attractive to soft money researchers. Programs can be carefully designed to benefit both the students and the research program.

McConnell, Mark L.

2000-01-01

291

Online testbench for LHCb High Level Trigger validation  

NASA Astrophysics Data System (ADS)

The High Level Trigger (HLT) and Data Acquisition (DAQ) system selects about 2 kHz of events out of the 40 MHz of beam crossings. The selected events are consolidated into files on an onsite storage and then sent to permanent storage for subsequent analysis on the Grid. For local and full-chain tests a method to exercise the data-flow through the High Level Trigger when there are no actual data is needed. In order to test the system as much as possible under identical conditions as for data-taking the solution is to inject data at the input of the HLT at a minimum rate of 2 kHz. This is done via a software implementation of the trigger system which sends data to the HLT. The application has to simulate that the data it sends come from real LHCb readout-boards. Both simulation data and previously recorded real data can be re-played through the system in this manner. As the data rate is high (100 MB/s), care has been taken to optimise the emulator for throughput from the Storage Area Network (SAN). The emulator can be run in stand-alone mode or run as a pseudo-subdetector of LHCb, allowing for use of all the standard run-control tools. The architecture, implementation and performance of the emulator will be presented.

Frank, M.; Garnier, J.; Gaspar, C.; Liu, G.; Neufeld, N.; Varela, A. S.

2010-04-01

292

Millimetre wave gyrotron operation at high efficiency and power levels  

NASA Astrophysics Data System (ADS)

Gyrotrons have reached impressive levels of performance such as pulse power output of a megawatt at frequencies higher than 100 GHz. Their applications include plasma heating for controlled fusion, high precision radar, RF source for accelerators, and ceramic heating. Operation in fundamental mode at millimeter wave frequencies requires the use of superconducting magnets. Harmonic operation offers the advantage of a lowered requirement of magnetic field intensity though at a lowered RF efficiency. Large-orbit gyrotrons are particularly suited for high harmonic operation. Techniques for enhancement of efficiency by energy recovery from spent beams are delineated for large as well as small-orbit gyrotrons. Achievement of high power levels in small-orbit gyrotrons is discussed along with related issues of complex cavities as well as cavities operating in 'whispering gallery' modes, and their mode stability. Quasi-optical gyrotrons have reduced mode density. However, mode competition still exists from longitudinal modes. Current research on single mode stability is outlined with reference to beam parameters.

Singh, Amarjit

1990-12-01

293

Identifying high-level features of texture perception  

NASA Astrophysics Data System (ADS)

A fundamental issue in texture analysis is that of deciding what textural features are important in texture perception, and how they are used. Experiments on human pre-attentive vision have identified several low-level features (such as orientation on blobs, and size of line segments), which are used in texture perception. However, the question of what higher level features of texture are used has not been adequately addressed. We designed an experiment to help identify the relevant higher order features of texture perceived by humans. We used twenty subjects, who were asked to perform an unsupervised classification of thirty pictures from Brodatz's album on texture. Each subject was asked to group these pictures into as many classes as desired. Both hierarchical cluster analysis and non-metric MDS were applied to the pooled similarity matrix generated from the subjects' groupings. A surprising outcome is that the MDS solutions fit the data very well. The stress in the two dimensional case is 0.10, and in the three dimensional case is 0.045. We rendered the original textures in these coordinate systems, and interpreted the (rotated) axes. It appears that the axes in the 2D case correspond to periodicity versus irregularity, and directional versus non-directional. In the 3D case, the third dimension represents the structural complexity of the texture. Furthermore, the clusters identified by the hierarchical cluster analysis remain virtually intact in the MDS solution. The results of our experiment indicate that people use three high level features for texture perception. Future studies are needed to determine the appropriateness of these high-level features for computational texture analysis and classification.

Rao, A. Ravishankar; Lohse, Gerald L.

1992-08-01

294

Increased hepcidin levels in high-altitude pulmonary edema.  

PubMed

Low iron availability enhances hypoxic pulmonary vasoconstriction (HPV). Considering that reduced serum iron is caused by increased erythropoiesis, insufficient reabsorption, or elevated hepcidin levels, one might speculate that exaggerated HPV in high-altitude pulmonary edema (HAPE) is related to low serum iron. To test this notion we measured serum iron and hepcidin in blood samples obtained in previously published studies at low altitude and during 2 days at 4,559 m (HA1, HA2) from controls, individuals with HAPE, and HAPE-susceptible individuals where prophylactic dexamethasone and tadalafil prevented HAPE. As reported, at 4,559 m pulmonary arterial pressure was increased in healthy volunteers but reached higher levels in HAPE. Serum iron levels were reduced in all groups at HA2. Hepcidin levels were reduced in all groups at HA1 and HA2 except in HAPE, where hepcidin was decreased at HA1 but unexpectedly high at HA2. Elevated hepcidin in HAPE correlated with increased IL-6 at HA2, suggesting that an inflammatory response related to HAPE contributes to increased hepcidin. Likewise, platelet-derived growth factor, a regulator of hepcidin, was increased at HA1 and HA2 in controls but not in HAPE, suggesting that hypoxia-controlled factors that regulate serum iron are inappropriately expressed in HAPE. In summary, we found that HAPE is associated with inappropriate expression of hepcidin without inducing expected changes in serum iron within 2 days at HA, likely due to too short time. Although hepcidin expression is uncoupled from serum iron availability and hypoxia in individuals developing HAPE, our findings indicate that serum iron is not related with exaggerated HPV. PMID:25525212

Altamura, Sandro; Bärtsch, Peter; Dehnert, Christoph; Maggiorini, Marco; Weiss, Günter; Theurl, Igor; Muckenthaler, Martina U; Mairbäurl, Heimo

2015-02-01

295

Brane-Production and the Neutrino-Nucleon cross section at Ultra High Energies in Low Scale Gravity Models  

E-print Network

The origin of the ultra high energy cosmic ray (UHECR) showers has remained as a mystery among particle physicists and astrophysicists. In low scale gravity models, where the neutrino-nucleon cross section rises to typical hadronic values at energies above $10^{20}$ eV, the neutrino becomes a candidate for the primary that initiates these showers. We calculate the neutrino-nucleon cross section at ultra high energies by assuming that it is dominated by the production of p-branes. We show, using a generalized Randall-Sundrum model, that the neutrino-nucleon cross-section at neutrino energies of $10^{11}$ GeV is of the order of 100 mb, which is required for explaining UHECR events. Similar result also follows in other models such as the Lykken-Randall model.

Pankaj Jain; Supriya Kar; Sukanta Panda

2002-10-16

296

Precision gravity detection - Gradiometry and/or radiometry  

NASA Technical Reports Server (NTRS)

Current knowledge concerning the earth's gravity field is limited to about 1500-2000 km resolution. However, the resolution of gravity anomalies having a spatial extent of 100-1000 km over the entire globe is needed for important geophysical and geodetic applications. In the near future satellite altimetry will be used to determine the ocean geoid at the 10 cm - 1 m level. In order to provide a similar level of resolutions over the land regions, there exists a need for utilizing new promising techniques such as gravity gradiometry and new radiometric measurements, viz., satellite-to-satellite tracking. Satellite-to-satellite tracking techniques have shown potential for improving the medium wavelength component of the gravity field. The gravity gradiometer has not yet been tested on board a satellite. The reported analysis includes a simplified theoretical model to compare the effectiveness of the gradiometer measurements and radiometric measurements for high resolution gravity field determination, and the direct estimation of local gravity anomalies represented by point masses using a simulated gravity gradiometer and satellite-to-satellite tracking data.

Ananda, M.

1977-01-01

297

Turbulence Investigations With High-Resolution Simulations of Dilute Suspension Particle-Laden Gravity Currents  

NASA Astrophysics Data System (ADS)

Gravity currents are very common in nature, either in atmosphere (due to sea-breeze fronts), in mountain avalanches (in airborne snow or debris flow), or in the ocean due to turbidity currents or river plumes (Simpson, 1982). In this numerical study, we focus on particle-laden hyperpycnal flows (negative-buoyancy), where the dynamics play a central role in the formation of hydrocarbon reservoirs (Meiburg & Kneller, 2009). Moreover, these particle-driven gravity currents are often extremely dangerous for the stability of submarine structures placed near the sea-floor (like pipelines or submarines cables). It is clear that the understanding of the physical mechanism associated with these currents and the correct prediction of their main features are of great importance for practical as well as theoretical purposes. For this numerical work, we are interested in the prediction of a mono-disperse dilute suspension particle-laden flow in the typical lock-exchange configuration. We consider only flat surfaces using DNS (Direct Numerical Simulation). Our approach takes into account the possibility of particles deposition but ignores erosion and/or re-suspension. Previous results for this kind of flows were obtained in laboratory experiments with Reynolds numbers up to 10400 (De Rooij & Dalziel, 2001), or by numerical simulations at moderate Reynolds numbers, up to 5000 for a 2D case (Nasr-Azadani, Hall & Meiburg, 2011) and up to 2236 for a 3D (Necker, Härtel, Kleiser & Meiburg, 2002) case with a Reynolds number based on the buoyancy velocity. It was shown that boundary conditions, initial lock configuration and different particle sizes can have a strong influence on the main characteristics of this kind of flows. The main objective of this numerical study is to undertake unprecedented simulations in order to focus on the turbulence and to investigate the effect of the Reynolds number in such flows. We want to investigate the turbulent mechanism in gravity currents such as local production and dissipation and their relationships with the main features of the flow for different Reynolds numbers, ranging from 2236 to 10000 for 2D and 3D cases. The main features of the flow will be related to the temporal evolution of the front location, sedimentation rate and the resulting streamwise deposit profiles. In particular, we will investigate the flow energy budget where the balance between kinetic and potential energy with dissipation (due to convective fluid motion and Stokes flow around particles) will be analysed in detail, using comparisons with previous experimental and numerical works.

Espath, L.; Pinto, L.; Laizet, S.; Silvestrini, J.; Scientific Team of DNS on Gravity Currents

2013-05-01

298

Salivary Fluoride Levels after Use of High-Fluoride Dentifrice  

PubMed Central

The aim of the study was to evaluate salivary fluoride (F) availability after toothbrushing with a high-F dentifrice. Twelve adult volunteers took part in this crossover and blind study. F concentration in saliva was determined after brushing with a high-F dentifrice (5000?µg?F/g) or with a conventional F concentration dentifrice (1100?µg?F/g) followed by a 15?mL distilled water rinse. Samples of nonstimulated saliva were collected on the following times: before (baseline), and immediately after spit (time = 0) and after 1, 2, 3, 4, 5, 10, 15, 20, 30, 45, 60, 90, and 120?min. F analysis was performed with a fluoride-sensitive electrode and the area under curve of F salivary concentration × time (µg?F/mL × min?1) was calculated. At baseline, no significant difference was found among dentifrices (P > 0.05). After brushing, both dentifrices caused an elevated fluoride level in saliva; however salivary F concentration was significantly higher at all times, when high-F dentifrice was used (P < 0.01). Even after 120?min, salivary F concentration was still higher than the baseline values for both dentifrices (P < 0.001). High-F dentifrice enhanced the bioavailability of salivary F, being an option for caries management in patients with high caries risk.

Vale, Glauber Campos; Cruz, Priscila Figueiredo; Bohn, Ana Clarissa Cavalcante Elvas; de Moura, Marcoeli Silva

2015-01-01

299

Development of a High Level Waste Tank Inspection System  

SciTech Connect

The Westinghouse Savannah River Technology Center was requested by it`s sister site, West Valley Nuclear Service (WVNS), to develop a remote inspection system to gather wall thickness readings of their High Level Waste Tanks. WVNS management chose to take a proactive approach to gain current information on two tanks t hat had been in service since the early 70`s. The tanks contain high level waste, are buried underground, and have only two access ports to an annular space between the tank and the secondary concrete vault. A specialized remote system was proposed to provide both a visual surveillance and ultrasonic thickness measurements of the tank walls. A magnetic wheeled crawler was the basis for the remote delivery system integrated with an off-the-shelf Ultrasonic Data Acquisition System. A development program was initiated for Savannah River Technology Center (SRTC) to design, fabricate, and test a remote system based on the Crawler. The system was completed and involved three crawlers to perform the needed tasks, an Ultrasonic Crawler, a Camera Crawler, and a Surface Prep Crawler. The crawlers were computer controlled so that their operation could be done remotely and their position on the wall could be tracked. The Ultrasonic Crawler controls were interfaced with ABB Amdata`s I-PC, Ultrasonic Data Acquisition System so that thickness mapping of the wall could be obtained. A second system was requested by Westinghouse Savannah River Company (WSRC), to perform just ultrasonic mapping on their similar Waste Storage Tanks; however, the system needed to be interfaced with the P-scan Ultrasonic Data Acquisition System. Both remote inspection systems were completed 9/94. Qualifications tests were conducted by WVNS prior to implementation on the actual tank and tank development was achieved 10/94. The second inspection system was deployed at WSRC 11/94 with success, and the system is now in continuous service inspecting the remaining high level waste tanks at WSRC.

Appel, D.K.; Loibl, M.W. [Westinghouse Savannah River Company, SC (United States); Meese, D.C. [Westinghouse West Valley Nuclear Services, West Valley, NY (United States)

1995-03-21

300

High iron level in early pregnancy increased glucose intolerance.  

PubMed

High iron stores in pregnancy are essential in preventing negative outcomes for both infants and mothers; however the risk of gestational diabetes mellitus (GDM) might also be increased. We intend to study the relationship between increased iron stores in early pregnancy and the risk of glucose intolerance and GDM. This prospective, observational, single-hospital study involved 104 non-anemic pregnant women, divided into 4 groups based on the quartile values for ferritin at the first trimester of pregnancy. All participants were screened for GDM with 75-g oral glucose tolerance test (OGTT) at 24-28 weeks' gestation. We observed that ferritin levels at early pregnancy were significantly correlated to glucose level after OGTT at 1-h and 2-h (rho=0.21, p<0.05; rho=0.43, p<0.001 respectively). Furthermore, in the higher quartile for ferritin (>38.8?g/L) glycemia at 2-h OGTT was significantly higher than in the others quartiles (p=0.002). In multivariate regression analysis, serum ferritin was a significant determinant of glycemia at 2-h OGTT. Although we did not find a significant association in the incidence of GDM in women with higher serum ferritin levels, probably in reason to the limit power of our study, our data demonstrated that the role of iron excess is tightly involved in the pathogenesis of glucose intolerance. We report for the first time that high ferritin values in early pregnancy are predictors of impaired glucose tolerance in non-anemic women. Individual iron supplementation should be evaluated in order to minimize glucose impairment risk in women with high risk of diabetes. PMID:25441227

Zein, Salam; Rachidi, Samar; Awada, Sanaa; Osman, Mireille; Al-Hajje, Amal; Shami, Nadine; Sharara, Iman; Cheikh-Ali, Khawla; Salameh, Pascale; Hininger-Favier, Isabelle

2015-04-01

301

HIGH LEVELS OF URANIUM IN GROUNDWATER OF ULAANBAATAR, MONGOLIA  

PubMed Central

Water samples collected from 129 wells in seven of the nine sub-divisions of Ulaanbaatar were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) using Clean Lab methods. The levels of many trace elements were found to be very low with the average concentrations (ranges in brackets) being 0.9 (<0.1-7.9) ?g/L for As; 7.7 (0.12-177) ?g/L for Mn; 0.2 (<0.05-1.9) ?g/L for Co; 16 (<0.1-686) ?g/L for Zn; 0.7 (<0.1-1.8) ?g/L for Se; <0.1 (<0.02-0.69) ?g/L for Cd; and 1.3 (<0.02-32) ?g/L for Pb. The levels of uranium were surprisingly elevated (mean, 4.6 ?g/L; range <0.01-57 ?g/L, with the values for many samples exceeding the World Health Organization's guideline of 15 ?g/L for uranium in drinking water. Local rocks and soils appear to be the natural source of the uranium. The levels of uranium in Ulaanbaatar's groundwater are in the range that has been associated with nephrotoxicity, high blood pressure, bone dysfunction and likely reproductive impairment in human populations. We consider the risk associated with drinking the groundwater with elevated levels of uranium in Ulaanbaatar to be a matter for some public health concern and conclude that the paucity of data on chronic effects of low level exposure is a risk factor for continuing the injury to many people in this city. PMID:22142646

Nriagu, Jerome; Nam, Dong-Ha; Ayanwola, Titilayo A.; Dinh, Hau; Erdenechimeg, Erdenebayar; Ochir, Chimedsuren; Bolormaa, Tsend-Ayush

2011-01-01

302

Time-variable gravity signal in Greenland revealed by high-low satellite-to-satellite tracking  

NASA Astrophysics Data System (ADS)

In the event of a termination of the Gravity Recovery and Climate Experiment (GRACE) mission before the launch of GRACE Follow-On (due for launch in 2017), high-low satellite-to-satellite tracking (hl-SST) will be the only dedicated observing system with global coverage available to measure the time-variable gravity field (TVG) on a monthly or even shorter time scale. Until recently, hl-SST TVG observations were of poor quality and hardly improved the performance of Satellite Laser Ranging observations. To date, they have been of only very limited usefulness to geophysical or environmental investigations. In this paper, we apply a thorough reprocessing strategy and a dedicated Kalman filter to Challenging Minisatellite Payload (CHAMP) data to demonstrate that it is possible to derive the very long-wavelength TVG features down to spatial scales of approximately 2000 km at the annual frequency and for multi-year trends. The results are validated against GRACE data and surface height changes from long-term GPS ground stations in Greenland. We find that the quality of the CHAMP solutions is sufficient to derive long-term trends and annual amplitudes of mass change over Greenland. We conclude that hl-SST is a viable source of information for TVG and can serve to some extent to bridge a possible gap between the end-of-life of GRACE and the availability of GRACE Follow-On.

Weigelt, M.; Dam, T.; Jäggi, A.; Prange, L.; Tourian, M. J.; Keller, W.; Sneeuw, N.

2013-07-01

303

Modern Alchemy: Solidifying high-level nuclear waste  

SciTech Connect

The U.S. Department of Energy is putting a modern version of alchemy to work to produce an answer to a decades-old problem. It is taking place at the Savannah River Site (SRS) in Aiken, South Carolina and at the West Valley Demonstration Project (WVDP) near Buffalo, New York. At both locations, contractor Westinghouse Electric Corporation is applying technology that is turning liquid high-level radioactive waste (HLW) into a stabilized, durable glass for safer and easier management. The process is called vitrification. SRS and WVDP are now operating the nation`s first full-scale HLW vitrification plants.

Newton, C.C.

1997-07-01

304

High-field level crossing in atomic hydrogen  

NASA Astrophysics Data System (ADS)

In hydrogen, an external magnetic field, which we calculate to be ?16.65 T, cancels the internal field caused by the electron motion in the magnetic sublevels with mJ=+1 /2 . This results in an energy-level degeneracy between states with nuclear magnetic sublevels mI of opposite signs. The evaluation of this field has been calculated previously with the use of the low-field quantum numbers F , mF . We show that this calculation is considerably simpler in the high-field mJ, mI representation. A comparison is given with the earlier work.

Lynch, Kara M.; Flanagan, Kieran; Stroke, H. Henry

2015-04-01

305

Solidification of Savannah River Plant high-level waste  

SciTech Connect

The Department of Energy, in accord with recommendations from the Du Pont Company, has started construction of a Defense Waste Processing Facility (DWPF) at the Savannah River Plant. The facility should be completed by the end of 1988, and full-scale operation should begin in 1990. This facility will immobilize in borosilicate glass the large quantity of high-level radioactive waste now stored at the plant plus the waste to be generated from continued chemical reprocessing operations. The existing wastes at the Savannah River Plant will be completely converted by about 2010. 21 figures.

Maher, R; Shafranek, L F; Stevens, III, W R

1983-01-01

306

CLASSIFICATION OF THE MGR DEFENSE HIGH LEVEL WASTE DISPOSAL CONTIANER  

SciTech Connect

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) defense high-level waste disposal container system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333PY ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).

J.A. Ziegler

1999-08-31

307

Management of high-level waste repository siting.  

PubMed

The selection of sites to store high-level radioactive waste will require more than technical decisions; an acceptable site must gain widespread public support. Ad hoc approaches have recently served as a stimulus to overcome institutional inertia in radioactive waste management, as exemplified by the Interagency Review Group and the State Planning Council for Radioactive Waste Management, but ad hoc approaches have not characteristically succeeded in resolving intense conflicts. Acceptable sites can best be established through traditional processes of legal and scientific advocacy, and their ultimate legitimacy will depend on the proper use of established democratic processes. PMID:17807127

Hill, D; Pierce, B L; Metz, W C; Rowe, M D; Haefele, E T; Bryant, F C; Tuthill, E J

1982-11-26

308

Market Designs for High Levels of Variable Generation: Preprint  

SciTech Connect

Variable renewable generation is increasing in penetration in modern power systems, leading to higher variability in the supply and price of electricity as well as lower average spot prices. This raises new challenges, particularly in ensuring sufficient capacity and flexibility from conventional technologies. Because the fixed costs and lifetimes of electricity generation investments are significant, designing markets and regulations that ensure the efficient integration of renewable generation is a significant challenge. This papers reviews the state of play of market designs for high levels of variable generation in the United States and Europe and considers new developments in both regions.

Milligan, M.; Holttinen, H.; Kiviluoma, J.; Orths, A.; Lynch, M.; Soder, L.

2014-10-01

309

High level waste at Hanford: Potential for waste loading maximization  

SciTech Connect

The loading of Hanford nuclear waste in borosilicate glass is limited by phase-related phenomena, such as crystallization or formation of immiscible liquids, and by breakdown of the glass structure because of an excessive concentration of modifiers. The phase-related phenomena cause both processing and product quality problems. The deterioration of product durability determines the ultimate waste loading limit if all processing problems are resolved. Concrete examples and mass-balance based calculations show that a substantial potential exists for increasing waste loading of high-level wastes that contain a large fraction of refractory components.

Hrma, P.R.; Bailey, A.W.

1995-09-01

310

Corrosion and failure processes in high-level waste tanks  

SciTech Connect

A large amount of radioactive waste has been stored safely at the Savannah River and Hanford sites over the past 46 years. The aim of this report is to review the experimental corrosion studies at Savannah River and Hanford with the intention of identifying the types and rates of corrosion encountered and indicate how these data contribute to tank failure predictions. The compositions of the High-Level Wastes, mild steels used in the construction of the waste tanks and degradation-modes particularly stress corrosion cracking and pitting are discussed. Current concerns at the Hanford Site are highlighted.

Mahidhara, R.K.; Elleman, T.S.; Murty, K.L. [North Carolina State Univ., Raleigh, NC (United States)

1992-11-01

311

High-level wastes: DOE names three sites for characterization  

SciTech Connect

DOE announced in May 1986 that there will be there site characterization studies made to determine suitability for a high-level radioactive waste repository. The studies will include several test drillings to the proposed disposal depths. Yucca Mountain, Nevada; Deaf Smith Country, Texas, and Hanford, Washington were identified as the study sites, and further studies for a second repository site in the East were postponed. The affected states all filed suits in federal circuit courts because they were given no advance warning of the announcement of their selection or the decision to suspend work on a second repository. Criticisms of the selection process include the narrowing or DOE options.

NONE

1986-07-01

312

High-level neutron coincidence counter maintenance manual  

SciTech Connect

High-level neutron coincidence counter operational (field) calibration and usage is well known. This manual makes explicit basic (shop) check-out, calibration, and testing of new units and is a guide for repair of failed in-service units. Operational criteria for the major electronic functions are detailed, as are adjustments and calibration procedures, and recurrent mechanical/electromechanical problems are addressed. Some system tests are included for quality assurance. Data on nonstandard large-scale integrated (circuit) components and a schematic set are also included.

Swansen, J.; Collinsworth, P.

1983-05-01

313

High levels of subgenomic HCV plasma RNA in immunosilent infections  

PubMed Central

A genetic analysis of hepatitis C virus (HCV) in rare blood donors who remained HCV seronegative despite long-term high-level viremia revealed the chronic presence of HCV genomes with large in frame deletions in their structural genes. Full-length HCV genomes were only detected as minority variants. In one immunodeficiency virus (HIV) co-infected donor the truncated HCV genome transiently decreased in frequency concomitant with delayed seroconversion and re-emerged following partial seroreversion. The long-term production of heavily truncated HCV genomes in vivo suggests that these viruses retained the necessary elements for RNA replication while the deleted structural functions necessary for their spread in vivo was provided in trans by wild type helper virus in co-infected cells. The absence of immunological pressure and a high viral load may therefore promote the emergence of truncated HCV subgenomic replicons in vivo. PMID:17493654

Bernardin, Flavien; Stramer, Susan; Rehermann, Barbara; Page-Shafer, Kimberly; Cooper, Stewart; Bangsberg, David; Hahn, Judith; Tobler, Leslie; Busch, Michael; Delwart, Eric

2007-01-01

314

System-Level Virtualization for High Performance Computing  

SciTech Connect

System-level virtualization has been a research topic since the 70's but regained popularity during the past few years because of the availability of efficient solution such as Xen and the implementation of hardware support in commodity processors (e.g. Intel-VT, AMD-V). However, a majority of system-level virtualization projects is guided by the server consolidation market. As a result, current virtualization solutions appear to not be suitable for high performance computing (HPC) which is typically based on large-scale systems. On another hand there is significant interest in exploiting virtual machines (VMs) within HPC for a number of other reasons. By virtualizing the machine, one is able to run a variety of operating systems and environments as needed by the applications. Virtualization allows users to isolate workloads, improving security and reliability. It is also possible to support non-native environments and/or legacy operating environments through virtualization. In addition, it is possible to balance work loads, use migration techniques to relocate applications from failing machines, and isolate fault systems for repair. This document presents the challenges for the implementation of a system-level virtualization solution for HPC. It also presents a brief survey of the different approaches and techniques to address these challenges.

Vallee, Geoffroy R [ORNL; Naughton, III, Thomas J [ORNL; Engelmann, Christian [ORNL; Ong, Hong Hoe [ORNL; Scott, Stephen L [ORNL

2008-01-01

315

Crystalline patterns of electrons in high Landau levels  

NASA Astrophysics Data System (ADS)

We consider a clean two-dimensional electron liquid in a transverse magnetic field at non-integral filling factors larger than four. We show that the traditional description of the upper, partially filled Landau level as a ``compressible liquid'' is not correct on fine length scales: instead of the uniform distribution of the electron density, there exist domains with filling factor equal to one and zero. When the filling factor of the upper Landau level is close to one half, the domains have the form of parallel stripes alternating with a spatial period close to three cyclotron radii. Away from a small interval around the half-filling, a ``bubble'' phase is more favorable. The reason for the domain formation is the characteristic ring-like shape of the electron wave functions at high Landau levels, due to which certain periodic variations of the local filling factor do not lead to the appreciable charge density variations. At the same time the fact that the lattice constant of the predicted crystalline structures greatly exceeds the magnetic length makes them stable against quantum melting into a Laughlin-type liquid. The length scale of the predicted patterns is expected to be within the resolution of novel two-dimensional imaging technics. This work has been done in collaboration with A. A. Koulakov and B. I. Shklovskii.

Fogler, M. M.

1998-03-01

316

Pupil responses to high-level image content.  

PubMed

The link between arousal and pupil dilation is well studied, but it is less known that other cognitive processes can trigger pupil responses. Here we present evidence that pupil responses can be induced by high-level scene processing, independent of changes in low-level features or arousal. In Experiment 1, we recorded changes in pupil diameter of observers while they viewed a variety of natural scenes with or without a sun that were presented either upright or inverted. Image inversion had the strongest effect on the pupil responses. The pupil constricted more to the onset of upright images as compared to inverted images. Furthermore, the amplitudes of pupil constrictions to viewing images containing a sun were larger relative to control images. In Experiment 2, we presented cartoon versions of upright and inverted pictures that included either a sun or a moon. The image backgrounds were kept identical across conditions. Similar to Experiment 1, upright images triggered pupil constrictions with larger amplitudes than inverted images and images of the sun evoked greater pupil contraction than images of the moon. We suggest that the modulations of pupil responses were due to higher-level interpretations of image content. PMID:23685390

Naber, Marnix; Nakayama, Ken

2013-01-01

317

VITRIFICATION OF HIGH LEVEL WASTE AT THE SAVANNAH RIVER SITE  

SciTech Connect

The objective of this study was to experimentally measure the properties and performance of a series of glasses with compositions that could represent high level waste Sludge Batch 5 (SB5) as vitrified at the Savannah River Site Defense Waste Processing Facility. These data were used to guide frit optimization efforts as the SB5 composition was finalized. Glass compositions for this study were developed by combining a series of SB5 composition projections with a group of candidate frits. The study glasses were fabricated using depleted uranium and their chemical compositions, crystalline contents and chemical durabilities were characterized. Trevorite was the only crystalline phase that was identified in a few of the study glasses after slow cooling, and is not of concern as spinels have been shown to have little impact on the durability of high level waste glasses. Chemical durability was quantified using the Product Consistency Test (PCT). All of the glasses had very acceptable durability performance. The results of this study indicate that a frit composition can be identified that will provide a processable and durable glass when combined with SB5.

Fox, K.; Peeler, D.

2009-06-17

318

Behavior construction and refinement from high-level specifications  

NASA Astrophysics Data System (ADS)

Mobile robots are excellent examples of systems that need to show a high level of autonomy. Often robots are loosely supervised by humans who are not intimately familiar with the inner workings of the robot. We cannot generally predict exact environmental conditions in which the robot will operate in advance. This means that the behavior must be adapted in the field. Untrained individuals cannot (and probably should not) program the robot to effect these changes. We need a system that will (a) allow re-tasking, and (b) allow adaptation of the behavior to the specific conditions in the field. In this paper we concentrate on (b). We will describe how to assemble controllers, based on high-level descriptions of the behavior. We will show how the behavior can be tuned by the human, despite not knowing how the code is put together. We will also show how this can be done automatically, using reinforcement learning, and point out the problems that must be overcome for this approach to work.

Martignoni, Andrew J., III; Smart, William D.

2004-12-01

319

How to achieve high-level expression of microbial enzymes  

PubMed Central

Microbial enzymes have been used in a large number of fields, such as chemical, agricultural and biopharmaceutical industries. The enzyme production rate and yield are the main factors to consider when choosing the appropriate expression system for the production of recombinant proteins. Recombinant enzymes have been expressed in bacteria (e.g., Escherichia coli, Bacillus and lactic acid bacteria), filamentous fungi (e.g., Aspergillus) and yeasts (e.g., Pichia pastoris). The favorable and very advantageous characteristics of these species have resulted in an increasing number of biotechnological applications. Bacterial hosts (e.g., E. coli) can be used to quickly and easily overexpress recombinant enzymes; however, bacterial systems cannot express very large proteins and proteins that require post-translational modifications. The main bacterial expression hosts, with the exception of lactic acid bacteria and filamentous fungi, can produce several toxins which are not compatible with the expression of recombinant enzymes in food and drugs. However, due to the multiplicity of the physiological impacts arising from high-level expression of genes encoding the enzymes and expression hosts, the goal of overproduction can hardly be achieved, and therefore, the yield of recombinant enzymes is limited. In this review, the recent strategies used for the high-level expression of microbial enzymes in the hosts mentioned above are summarized and the prospects are also discussed. We hope this review will contribute to the development of the enzyme-related research field. PMID:23686280

Liu, Long; Yang, Haiquan; Shin, Hyun-dong; Chen, Rachel R.; Li, Jianghua; Du, Guocheng; Chen, Jian

2013-01-01

320

Spent fuel and high-level radioactive waste transportation report  

SciTech Connect

This publication is intended to provide its readers with an introduction to the issues surrounding the subject of transportation of spent nuclear fuel and high-level radioactive waste, especially as those issues impact the southern region of the United States. It was originally issued by the Southern States Energy Board (SSEB) in July 1987 as the Spent Nuclear Fuel and High-Level Radioactive Waste Transportation Primer, a document patterned on work performed by the Western Interstate Energy Board and designed as a ``comprehensive overview of the issues.`` This work differs from that earlier effort in that it is designed for the educated layman with little or no background in nuclear waste issues. In addition, this document is not a comprehensive examination of nuclear waste issues but should instead serve as a general introduction to the subject. Owing to changes in the nuclear waste management system, program activities by the US Department of Energy and other federal agencies and developing technologies, much of this information is dated quickly. While this report uses the most recent data available, readers should keep in mind that some of the material is subject to rapid change. SSEB plans periodic updates in the future to account for changes in the program. Replacement pages will be supplied to all parties in receipt of this publication provided they remain on the SSEB mailing list.

Not Available

1990-11-01

321

Spent Fuel and High-Level Radioactive Waste Transportation Report  

SciTech Connect

This publication is intended to provide its readers with an introduction to the issues surrounding the subject of transportation of spent nuclear fuel and high-level radioactive waste, especially as those issues impact the southern region of the United States. It was originally issued by SSEB in July 1987 as the Spent Nuclear Fuel and High-Level Radioactive Waste Transportation Primer, a document patterned on work performed by the Western Interstate Energy Board and designed as a ``comprehensive overview of the issues.`` This work differs from that earlier effort in that it is designed for the educated layman with little or no background in nuclear waste Issues. In addition. this document is not a comprehensive examination of nuclear waste issues but should instead serve as a general introduction to the subject. Owing to changes in the nuclear waste management system, program activities by the US Department of Energy and other federal agencies and developing technologies, much of this information is dated quickly. While this report uses the most recent data available, readers should keep in mind that some of the material is subject to rapid change. SSEB plans periodic updates in the future to account for changes in the program. Replacement pages will be supplied to all parties in receipt of this publication provided they remain on the SSEB mailing list.

Not Available

1992-03-01

322

Spent fuel and high-level radioactive waste transportation report  

SciTech Connect

This publication is intended to provide its readers with an introduction to the issues surrounding the subject of transportation of spent nuclear fuel and high-level radioactive waste, especially as those issues impact the southern region of the United States. It was originally issued by the Southern States Energy Board (SSEB) in July 1987 as the Spent Nuclear Fuel and High-Level Radioactive Waste Transportation Primer, a document patterned on work performed by the Western Interstate Energy Board and designed as a ``comprehensive overview of the issues.`` This work differs from that earlier effort in that it is designed for the educated layman with little or no background in nuclear waste issues. In addition, this document is not a comprehensive examination of nuclear waste issues but should instead serve as a general introduction to the subject. Owing to changes in the nuclear waste management system, program activities by the US Department of Energy and other federal agencies and developing technologies, much of this information is dated quickly. While this report uses the most recent data available, readers should keep in mind that some of the material is subject to rapid change. SSEB plans periodic updates in the future to account for changes in the program. Replacement pages sew be supplied to all parties in receipt of this publication provided they remain on the SSEB mailing list.

Not Available

1989-11-01

323

ATW system impact on high-level waste  

SciTech Connect

This report discusses the Accelerator Transmutation of Waste (ATW) concept which aims at destruction of key long-lived radionuclides in high-level nuclear waste (HLW), both fission products and actinides. This focus makes it different from most other transmutation concepts which concentrate primarily on actinide burning. The ATW system uses an accelerator-driven, sub-critical assembly to create an intense thermal neutron environment for radionuclide transmutation. This feature allows rapid transmutation under low-inventory system conditions, which in turn, has a direct impact on the size of chemical separations and materials handling components of the system. Inventories in ATW are factors of eight to thirty times smaller than reactor systems of equivalent thermal power. Chemical separations systems are relatively small in scale and can be optimized to achieve high decontamination factors and minimized waste streams. The low-inventory feature also directly impacts material amounts remaining in the system at its end of life. In addition to its low-inventory operation, the accelerator-driven neutron source features of ATW are key to providing a sufficient level of neutrons to allow transmutation of long-lived fission products.

Arthur, E.D.

1992-12-01

324

ATW system impact on high-level waste  

SciTech Connect

This report discusses the Accelerator Transmutation of Waste (ATW) concept which aims at destruction of key long-lived radionuclides in high-level nuclear waste (HLW), both fission products and actinides. This focus makes it different from most other transmutation concepts which concentrate primarily on actinide burning. The ATW system uses an accelerator-driven, sub-critical assembly to create an intense thermal neutron environment for radionuclide transmutation. This feature allows rapid transmutation under low-inventory system conditions, which in turn, has a direct impact on the size of chemical separations and materials handling components of the system. Inventories in ATW are factors of eight to thirty times smaller than reactor systems of equivalent thermal power. Chemical separations systems are relatively small in scale and can be optimized to achieve high decontamination factors and minimized waste streams. The low-inventory feature also directly impacts material amounts remaining in the system at its end of life. In addition to its low-inventory operation, the accelerator-driven neutron source features of ATW are key to providing a sufficient level of neutrons to allow transmutation of long-lived fission products.

Arthur, E.D.

1992-01-01

325

LIQUIDUS TEMPERATURE AND PRIMARY CRYSTALLIZATION PHASES IN HIGH-ZIRCONIA HIGH-LEVEL WASTE BOROSILICATE GLASSES  

EPA Science Inventory

Liquidus temperature (TL) studies of high-Zr high-level waste (HLW) borosilicate glasses have identified three primary phases: baddelyite (ZrO2), zircon (ZrSiO4), and alkali-zirconium silicates, such as parakeldyshite (Na2ZrSi2O7). Using published TL data for HLW glasses with the...

326

Gravity Waves  

Atmospheric Science Data Center

article title:  Gravity Waves Ripple over Marine Stratocumulus Clouds   ... when a pebble is thrown into a still pond, such "gravity waves" sometimes appear when the relatively stable and stratified air masses ... Oct 29, 2003 Images:  Gravity Waves location:  Indian Ocean thumbnail:  ...

2013-04-19

327

Department of Energy pretreatment of high-level and low-level wastes  

SciTech Connect

The remediation of the 1 {times} 10{sup 8} gal of highly radioactive waste in the underground storage tanks (USTs) at five US Department of Energy (DOE) sites is one of DOE`s greatest challenges. Therefore, the DOE Office of Environmental Management has created the Tank Focus Area (TFA) to manage an integrated technology development program that results in the safe and efficient remediation of UST waste. The TFA has divided its efforts into five areas, which are safety, characterization, retrieval/closure, pretreatment, and immobilization. All DOE pretreatment activities are integrated by the Pretreatment Technical Integration Manager of the TFA. For FY 1996, the 14 pretreatment tasks are divided into 3 systems: supernate separations, sludge treatment, and solid/liquid separation. The plans and recent results of these TFA tasks, which include two 25,000-gal demonstrations and two former TFA tasks on Cs removal, are presented. The pretreatment goals are to minimize the volume of high-level waste and the radioactivity in low-level waste.

McGinnis, C.P.; Hunt, R.D.

1995-12-31

328

Effects of Body Orientation and Retinal Image Pitch on the Perception of Gravity-Referenced Eye Level (GREL)  

NASA Technical Reports Server (NTRS)

It has been asserted that the pitch orientation of a visual array and of an observer's body jointly determine the perception of GREL. The current study formally tests this assertion over an extended range with multiple combinations of visual and body pitch orientations. Ten subjects were individually secured in a Circolectric bed surrounded by a room (pitchroom) with walls that could be pitched at various angles with respect to gravity. The bed and the walls of the room were independently adjusted to each of five positions relative to gravitational vertical: -15, -7.5, 0, +7.5, and +15 degrees, yielding 25 combinations of body x room pitch angles, and retinal image pitch (RIP) conditions ranging from -30 to +30 degrees. Each subject set a target to apparent GREL while viewing it against a background of two electroluminescent strips on the outer edges of the far wall of the room. As determined by ANOVA, the orientation of the room, and its interaction with that of the observer, significantly altered GREL (p less than 0.01). Regression analysis showed that GREL was best described as a linear summation of the weighted independent contributions from a body-referenced mechanism (B) and a visual mechanism given by the orientation of the background array on the retina (RIP). The equation for this relationship is: GREL = .74 (B) +.64 (RIP) - 1.42; r-squared = .994.

Cohen, Malcolm M.; Guzy, Larry T.; Wade, Charles E. (Technical Monitor)

1994-01-01

329

Confidence Level and Sensitivity Limits in High Contrast Imaging  

SciTech Connect

In long adaptive optics corrected exposures, exoplanet detections are currently limited by speckle noise originating from the telescope and instrument optics, and it is expected that such noise will also limit future high-contrast imaging instruments for both ground and space-based telescopes. Previous theoretical analysis have shown that the time intensity variations of a single speckle follows a modified Rician. It is first demonstrated here that for a circular pupil this temporal intensity distribution also represents the speckle spatial intensity distribution at a fix separation from the point spread function center; this fact is demonstrated using numerical simulations for coronagraphic and non-coronagraphic data. The real statistical distribution of the noise needs to be taken into account explicitly when selecting a detection threshold appropriate for some desired confidence level. In this paper, a technique is described to obtain the pixel intensity distribution of an image and its corresponding confidence level as a function of the detection threshold. Using numerical simulations, it is shown that in the presence of speckles noise, a detection threshold up to three times higher is required to obtain a confidence level equivalent to that at 5{sigma} for Gaussian noise. The technique is then tested using TRIDENT CFHT and angular differential imaging NIRI Gemini adaptive optics data. It is found that the angular differential imaging technique produces quasi-Gaussian residuals, a remarkable result compared to classical adaptive optic imaging. A power-law is finally derived to predict the 1-3 x 10{sup -7} confidence level detection threshold when averaging a partially correlated non-Gaussian noise.

Marois, C

2007-11-07

330

Confidence Level and Sensitivity Limits in High Contrast Imaging  

SciTech Connect

In long adaptive optics corrected exposures, exoplanet detections are currently limited by speckle noise originating from the telescope and instrument optics, and it is expected that such noise will also limit future high-contrast imaging instruments for both ground and space-based telescopes. Previous theoretical analysis have shown that the time intensity variations of a single speckle follows a modified Rician. It is first demonstrated here that for a circular pupil this temporal intensity distribution also represents the speckle spatial intensity distribution at a fix separation from the point spread function center; this fact is demonstrated using numerical simulations for coronagraphic and non-coronagraphic data. The real statistical distribution of the noise needs to be taken into account explicitly when selecting a detection threshold appropriate for some desired confidence level. In this paper, a technique is described to obtain the pixel intensity distribution of an image and its corresponding confidence level as a function of the detection threshold. Using numerical simulations, it is shown that in the presence of speckles noise, a detection threshold up to three times higher is required to obtain a confidence level equivalent to that at 5{sigma} for Gaussian noise. The technique is then tested using TRIDENT CFHT and angular differential imaging NIRI Gemini adaptive optics data. It is found that the angular differential imaging technique produces quasi-Gaussian residuals, a remarkable result compared to classical adaptive optic imaging. A power-law is finally derived to predict the 1-3 x 10{sup -7} confidence level detection threshold when averaging a partially correlated non-Gaussian noise.

Marois, C; LaFreniere, D; Macintosh, B; Doyon, R

2008-06-02

331

Confidence Level and Sensitivity Limits in High Contrast Imaging  

E-print Network

In long adaptive optics corrected exposures, exoplanet detections are currently limited by speckle noise originating from the telescope and instrument optics, and it is expected that such noise will also limit future high-contrast imaging instruments for both ground and space-based telescopes. Previous theoretical analysis have shown that the time intensity variations of a single speckle follows a modified Rician. It is first demonstrated here that for a circular pupil this temporal intensity distribution also represents the speckle spatial intensity distribution at a fix separation from the point spread function center; this fact is demonstrated using numerical simulations for coronagraphic and non-coronagraphic data. The real statistical distribution of the noise needs to be taken into account explicitly when selecting a detection threshold appropriate for some desired confidence level. In this paper, a technique is described to obtain the pixel intensity distribution of an image and its corresponding confidence level as a function of the detection threshold. Using numerical simulations, it is shown that in the presence of speckles noise, a detection threshold up to three times higher is required to obtain a confidence level equivalent to that at 5sigma for Gaussian noise. The technique is then tested using TRIDENT CFHT and angular differential imaging NIRI Gemini adaptive optics data. It is found that the angular differential imaging technique produces quasi-Gaussian residuals, a remarkable result compared to classical adaptive optic imaging. A power-law is finally derived to predict the 1-3*10^-7 confidence level detection threshold when averaging a partially correlated non-Gaussian noise.

C. Marois; D. Lafreniere; B. Macintosh; R. Doyon

2007-09-21

332

Myocytes Oxygenation and High Energy Phosphate Levels during Hypoxia  

PubMed Central

Decrease of ambient oxygen level has been used in myocytes culture experiments in examining the responsiveness to stress secondary to hypoxia. However, none of these studies measure the myocytes oxygenation levels resulting in ambiguity as to whether there is insufficient oxygen delivery. This study examined the hypothesis that at a basal myocardial work state, adequate myocyte oxygenation would be maintained until extremely low arterial pO2 levels were reached. Myocyte pO2 values in normal dogs were calculated from the myocardial deoxymyoglobin (Mb- ?) levels using 1H-spectroscopy (MRS) and were normalized to Mb-? obtained after complete LAD occlusion. During Protocol 1 (n?=?6), Mb-? was measured during sequential reductions of the oxygen fraction of inspired gas (FIO2) from 40, 21, 15, 10, and 5%, while in protocol 2 (n?=?10) Mb-? was measured at FIO2 of 3%. Protocol 3 (n?=?9) evaluated time course of Mb-? during prolonged exposure to FIO2 of 5%. Myocardial blood flow (MBF) was measured with microspheres and high energy phosphate (HEP) levels were determined with 31P-MRS. MVO2 progressively increased in response to the progressive reduction of FIO2 that is accompanied by increased LV pressure, heart rate, and MBF. Mb-? was undetectable during FIO2 values of 21, 15, 10, and 5%. However, FIO2 of 3% or prolonged exposure to FIO2 of 5% caused progressive increases of Mb-? which were associated with decreases of PCr, ATP and the PCr/ATP ratio, as well as increases of inorganic phosphate. The intracellular PO2 values for 20% reductions of PCr and ATP were approximately 7.4 and 1.9 mmHg, respectively. These data demonstrate that in the in vivo system over a wide range of FIO2 and arterial pO2 levels, the myocyte pO2 values remain well above the Km value with respect to cytochrome oxidase, and oxygen availability does not limit mitochondrial oxidative phosphorylation at 5% FIO2. PMID:25268711

Jameel, Mohammad Nurulqadr; Hu, Qingsong; Zhang, Jianyi

2014-01-01

333

Using continuous GPS and absolute gravity to separate vertical land movements and changes in sea-level at tide-gauges in the UK.  

PubMed

Researchers investigating climate change have used historical tide-gauge measurements from all over the world to investigate the changes in sea-level that have occurred over the last century or so. However, such estimates are a combination of any true sea-level variations and any vertical movements of the land at the specific tide-gauge. For a tide- gauge record to be used to determine the climate related component of changes in sea-level, it is therefore necessary to correct for the vertical land movement component of the observed change in sea-level.In 1990, the Institute of Engineering Surveying and Space Geodesy and Proudman Oceanographic Laboratory started developing techniques based on the Global Positioning System (GPS) for measuring vertical land movements (VLM) at tide-gauges in the UK. This paper provides brief details of these early developments and shows how they led to the establishment of continuous GPS (CGPS) stations at a number of tide-gauges. The paper then goes on to discuss the use of absolute gravity (AG), as an independent technique for measuring VLM at tide-gauges. The most recent results, from CGPS time-series dating back to 1997 and AG time-series dating back to 1995/1996, are then used to demonstrate the complementarity of these two techniques and their potential for providing site-specific estimates of VLM at tide-gauges in the UK. PMID:16537148

Teferle, F N; Bingley, R M; Williams, S D P; Baker, T F; Dodson, A H

2006-04-15

334

Gravity in Gauge Mediation  

E-print Network

We investigate O'Raifeartaigh-type models for F-term supersymmetry breaking in gauge mediation scenarios in the presence of gravity. It is pointed out that the vacuum structure of those models is such that in metastable vacua gravity mediation contribution to scalar masses is always suppressed to the level below 1 percent, almost sufficient for avoiding FCNC problem. Close to that limit, gravitino mass can be in the range 10-100 GeV, opening several interesting possibilities for gauge mediation models, including Giudice-Masiero mechanism for mu and Bmu generation. Gravity sector can include stabilized moduli.

Zygmunt Lalak; Stefan Pokorski; Krzysztof Turzynski

2008-08-18

335

Gravity in Gauge Mediation  

E-print Network

We investigate O'Raifeartaigh-type models for F-term supersymmetry breaking in gauge mediation scenarios in the presence of gravity. It is pointed out that the vacuum structure of those models is such that in metastable vacua gravity mediation contribution to scalar masses is always suppressed to the level below 1 percent, almost sufficient for avoiding FCNC problem. Close to that limit, gravitino mass can be in the range 10-100 GeV, opening several interesting possibilities for gauge mediation models, including Giudice-Masiero mechanism for mu and Bmu generation. Gravity sector can include stabilized moduli.

Lalak, Zygmunt; Turzynski, Krzysztof

2008-01-01

336

High resolution sea-surface magnetic and gravity surveys of Panarea and Stromboli system: preliminary results of PANSTR-2010 cruise  

NASA Astrophysics Data System (ADS)

We present the preliminary results of a marine high-resolution magnetic and gravity survey of Panarea and Stromboli (Aeolian Islands, cruise R/V Urania PANSTR-2010), in the active, eastern sector of the volcanic arc in the Southern Tyrrhenian Sea (Italy). The Aeolian Arc can be subdivided into western, central and eastern sectors characterized by different structural and volcanological features and evolution. The eastern sector includes the two major volcanic edifices of Panarea and Stromboli. Active volcanism occurs at Stromboli with explosive eruptions and at Panarea with fumaroles and submarine degassing, including the recent, large burst of November 22nd 2002, that lasted several months with a consistent and sustained flux of CO2-dominated gas , orders of magnitude above the steady-state activity. On February 2010 a detailed network of sea-surface gravity (Microg LaCoste Air Sea S-54 model) and magnetic data (Marine Magnetics SeaSPY) were collected with line spacing of 500 m offshore Panarea and Stromboli, including a more detailed acquisition pattern around Panarea with 120 m spacing. Geophysical data acquired offshore Panarea and Stromboli provide a new insight into the deep crustal setting of these volcanic edifices. Low-frequency magnetic anomaly and positive complete Bouguer anomaly identify an intriguing local variation of the crustal properties in this area. Particular attention was drawn to the high-resolution data obtained in the area of the Islets (Lisca Nera, Lisca Bianca, Bottaro, Panarelli, Dattilo) located East of Panarea, where the last 2002 exhalative gas-crisis occurred. The comparison of the data sets of 2002, 2006 and 2010 showed variations of the magnetic properties, reflecting the modification of shallow crustal features and providing information on the hydrothermal system and the structural style of the area. In detail, analysis of new marine gravity data pointed to a local variation of density in the 2002 degassing area (between Dattilo and Lisca Bianca) with a sharp separation, in term of density properties, between the western group of islets and the eastern one. This differentiation seems not correlated to a variation of lithologies in the area, but it suggests the occurrence of local variation of density and/or of a thermal gradient between the two groups of islets. The contrasting structural setting of the eastern and western area of the Islets is also suggested by available GPS geodetic measurements. Detailed strain-rate analyses have been performed showing local, different deformation patterns.

Cocchi, L.; Bortoluzzi, G.; Muccini, F.; Ligi, M.; Carmisciano, C.; Cuffaro, M.; Romagnoli, C.

2011-12-01

337

High-Voltage-Input Level Translator Using Standard CMOS  

NASA Technical Reports Server (NTRS)

proposed integrated circuit would translate (1) a pair of input signals having a low differential potential and a possibly high common-mode potential into (2) a pair of output signals having the same low differential potential and a low common-mode potential. As used here, "low" and "high" refer to potentials that are, respectively, below or above the nominal supply potential (3.3 V) at which standard complementary metal oxide/semiconductor (CMOS) integrated circuits are designed to operate. The input common-mode potential could lie between 0 and 10 V; the output common-mode potential would be 2 V. This translation would make it possible to process the pair of signals by use of standard 3.3-V CMOS analog and/or mixed-signal (analog and digital) circuitry on the same integrated-circuit chip. A schematic of the circuit is shown in the figure. Standard 3.3-V CMOS circuitry cannot withstand input potentials greater than about 4 V. However, there are many applications that involve low-differential-potential, high-common-mode-potential input signal pairs and in which standard 3.3-V CMOS circuitry, which is relatively inexpensive, would be the most appropriate circuitry for performing other functions on the integrated-circuit chip that handles the high-potential input signals. Thus, there is a need to combine high-voltage input circuitry with standard low-voltage CMOS circuitry on the same integrated-circuit chip. The proposed circuit would satisfy this need. In the proposed circuit, the input signals would be coupled into both a level-shifting pair and a common-mode-sensing pair of CMOS transistors. The output of the level-shifting pair would be fed as input to a differential pair of transistors. The resulting differential current output would pass through six standoff transistors to be mirrored into an output branch by four heterojunction bipolar transistors. The mirrored differential current would be converted back to potential by a pair of diode-connected transistors, which, by virtue of being identical to the input transistors, would reproduce the input differential potential at the output

Yager, Jeremy A.; Mojarradi, Mohammad M.; Vo, Tuan A.; Blalock, Benjamin J.

2011-01-01

338

High-gravity-assisted pulsed laser ablation system for the fabrication of functionally graded material thin film  

NASA Astrophysics Data System (ADS)

This paper describes a novel method for the fabrication of a thin film deposited on an appropriate substrate having a continuous composition gradient. The composition gradient was achieved by a combination of pulsed laser ablation (PLA) of the target material with a very strong acceleration field generated on a moving disk rotating at a very high speed. The PLA process was used to produce a cloud of high-energy particles of the target material that will be deposited on a substrate placed on the rotating disk. After deposition, the particles will diffuse on the surface of the thin film under a strong acceleration field. The high energy of the particles and their diffusion on the substrate surface in a high-vacuum environment produces a macroscopic composition distribution in the thin film. We have constructed an experimental apparatus consisting of a vacuum chamber in which a circular disk made of titanium is driven by a high-frequency inductive motor. An acceleration field of up to 10 000 G can be generated by this apparatus. Functionally graded material thin films of FeSi2 with a continuous concentration gradient were successfully fabricated by this method under a gravity field of 5400 G. A significant advantage of this method is that it allows us to fabricate graded thin films with a very smooth surface covered by few droplets.

Nishiyama, T.; Morinaga, S.; Nagayama, K.

2009-03-01

339

High-gravity-assisted pulsed laser ablation system for the fabrication of functionally graded material thin film.  

PubMed

This paper describes a novel method for the fabrication of a thin film deposited on an appropriate substrate having a continuous composition gradient. The composition gradient was achieved by a combination of pulsed laser ablation (PLA) of the target material with a very strong acceleration field generated on a moving disk rotating at a very high speed. The PLA process was used to produce a cloud of high-energy particles of the target material that will be deposited on a substrate placed on the rotating disk. After deposition, the particles will diffuse on the surface of the thin film under a strong acceleration field. The high energy of the particles and their diffusion on the substrate surface in a high-vacuum environment produces a macroscopic composition distribution in the thin film. We have constructed an experimental apparatus consisting of a vacuum chamber in which a circular disk made of titanium is driven by a high-frequency inductive motor. An acceleration field of up to 10,000 G can be generated by this apparatus. Functionally graded material thin films of FeSi(2) with a continuous concentration gradient were successfully fabricated by this method under a gravity field of 5400 G. A significant advantage of this method is that it allows us to fabricate graded thin films with a very smooth surface covered by few droplets. PMID:19334931

Nishiyama, T; Morinaga, S; Nagayama, K

2009-03-01

340

Liouville gravity from Einstein gravity  

E-print Network

We show that Liouville gravity arises as the limit of pure Einstein gravity in 2+epsilon dimensions as epsilon goes to zero, provided Newton's constant scales with epsilon. Our procedure - spherical reduction, dualization, limit, dualizing back - passes several consistency tests: geometric properties, interactions with matter and the Bekenstein-Hawking entropy are as expected from Einstein gravity.

D. Grumiller; R. Jackiw

2007-12-28

341

Confidence Level and Sensitivity Limits in High Contrast Imaging  

E-print Network

In long adaptive optics corrected exposures, exoplanet detections are currently limited by speckle noise originating from the telescope and instrument optics, and it is expected that such noise will also limit future high-contrast imaging instruments for both ground and space-based telescopes. Previous theoretical analysis have shown that the time intensity variations of a single speckle follows a modified Rician. It is first demonstrated here that for a circular pupil this temporal intensity distribution also represents the speckle spatial intensity distribution at a fix separation from the point spread function center; this fact is demonstrated using numerical simulations for coronagraphic and non-coronagraphic data. The real statistical distribution of the noise needs to be taken into account explicitly when selecting a detection threshold appropriate for some desired confidence level. In this paper, a technique is described to obtain the pixel intensity distribution of an image and its corresponding confi...

Marois, C; MacIntosh, B; Doyon, R

2007-01-01

342

High level radioactive waste vitrification process equipment component testing  

SciTech Connect

Remote operability and maintainability of vitrification equipment were assessed under shielded-cell conditions. The equipment tested will be applied to immobilize high-level and transuranic liquid waste slurries that resulted from plutonium production for defense weapons. Equipment tested included: a turntable for handling waste canisters under the melter; a removable discharge cone in the melter overflow section; a thermocouple jumper that extends into a shielded cell; remote instrument and electrical connectors; remote, mechanical, and heat transfer aspects of the melter glass overflow section; a reamer to clean out plugged nozzles in the melter top; a closed circuit camera to view the melter interior; and a device to retrieve samples of the glass product. A test was also conducted to evaluate liquid metals for use in a liquid metal sealing system.

Siemens, D.H.; Heath, W.O.; Larson, D.E.; Craig, S.N.; Berger, D.N.; Goles, R.W.

1985-04-01

343

SIMULANT DEVELOPMENT FOR SAVANNAH RIVER SITE HIGH LEVEL WASTE  

SciTech Connect

The Defense Waste Processing Facility (DWPF) at the Savannah River Site vitrifies High Level Waste (HLW) for repository internment. The process consists of three major steps: waste pretreatment, vitrification, and canister decontamination/sealing. The HLW consists of insoluble metal hydroxides (primarily iron, aluminum, magnesium, manganese, and uranium) and soluble sodium salts (carbonate, hydroxide, nitrite, nitrate, and sulfate). The HLW is processed in large batches through DWPF; DWPF has recently completed processing Sludge Batch 3 (SB3) and is currently processing Sludge Batch 4 (SB4). The composition of metal species in SB4 is shown in Table 1 as a function of the ratio of a metal to iron. Simulants remove radioactive species and renormalize the remaining species. Supernate composition is shown in Table 2.

Stone, M; Russell Eibling, R; David Koopman, D; Dan Lambert, D; Paul Burket, P

2007-09-04

344

Transmutation of high-level radioactive waste - Perspectives  

E-print Network

In a fast neutron spectrum essentially all long-lived actinides (e.g. Plutonium) undergo fission and thus can be transmuted into generally short lived fission products. Innovative nuclear reactor concepts e.g. accelerator driven systems (ADS) are currently in development that foresee a closed fuel cycle. The majority of the fissile nuclides (uranium, plutonium) shall be used for power generation and only fission products will be put into final disposal that needs to last for a historical time scale of only 1000 years. For the transmutation of high-level radioactive waste a lot of research and development is still required. One aspect is the precise knowledge of nuclear data for reactions with fast neutrons. Nuclear reactions relevant for transmutation are being investigated in the framework of the european project ERINDA. First results from the new neutron time-of-flight facility nELBE at Helmholtz-Zentrum Dresden-Rossendorf will be presented.

Junghans, Arnd; Grosse, Eckart; Hannaske, Roland; Kögler, Toni; Massarczyk, Ralf; Schwengner, Ronald; Wagner, Andreas

2014-01-01

345

High-spin level scheme of Pb194  

NASA Astrophysics Data System (ADS)

High-spin states in Pb194 have been populated in the Er168(Si30,4n) reaction at 142 MeV. The emitted ? rays were detected by the EUROBALL III multidetector array. The level scheme was considerably extended and many previously observed ?-ray transitions were reordered. Four new magnetic rotational bands were observed. The energies and spins of the bandheads of all previously observed magnetic rotational bands were corrected based on the observation of new transitions. From nine observed bands, only one could not be connected to the lower lying states. Based on comparison systematics with neighboring Pb isotopes and tilted-axis cranking model calculations previously reported, configuration assignments to the observed bands have been made.

Kutsarova, T.; Stefanova, E. A.; Minkova, A.; Lalkovski, S.; Korichi, A.; Lopez-Martens, A.; Hannachi, F.; Hübel, H.; Görgen, A.; Jansen, A.; Schönwasser, G.; Khoo, T. L.; Herskind, B.; Bergström, M.; Bazzacco, D.; Podolyák, Z.

2009-01-01

346

High-spin level scheme of {sup 194}Pb  

SciTech Connect

High-spin states in {sup 194}Pb have been populated in the {sup 168}Er({sup 30}Si,4n) reaction at 142 MeV. The emitted {gamma} rays were detected by the EUROBALL III multidetector array. The level scheme was considerably extended and many previously observed {gamma}-ray transitions were reordered. Four new magnetic rotational bands were observed. The energies and spins of the bandheads of all previously observed magnetic rotational bands were corrected based on the observation of new transitions. From nine observed bands, only one could not be connected to the lower lying states. Based on comparison systematics with neighboring Pb isotopes and tilted-axis cranking model calculations previously reported, configuration assignments to the observed bands have been made.

Kutsarova, T.; Stefanova, E. A.; Minkova, A.; Lalkovski, S.; Korichi, A.; Lopez-Martens, A.; Hannachi, F.; Huebel, H.; Goergen, A.; Jansen, A.; Schoenwasser, G.; Khoo, T. L.; Herskind, B.; Bergstroem, M.; Bazzacco, D.; Podolyak, Z. [Institute for Nuclear Research and Nuclear Energy, BAS, BG-1784 Sofia (Bulgaria); Faculty of Physics, University of Sofia 'St. Kliment Ohridski', BG-1164 Sofia (Bulgaria); CSNSM Orsay, IN2P3/CNRS, F-91405 (France); HISKP, Helmholtz-Institute fuer Strahlen-und Kernphysik, Nussallee 14-16, D-53115 (Germany); ISKP, Universitaet Bonn, Nussallee 14-16, D-53115 (Germany); Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); The Niels Bohr Institute, Blegdamsvej 17, DK-2100 Copenhagen (Denmark); Dipartimento di Fisica, Universita di Padova and INFN Sezione di Padova, I-35131 Padova (Italy); INFN, Laboratori Nationali di Legnaro (Italy)

2009-01-15

347

Socioeconomic studies of high-level nuclear waste disposal  

SciTech Connect

The socioeconomic investigations of possible impacts of the proposed repository for high-level nuclear waste at Yucca Mountain, Nevada, have been unprecedented in several respects. They bear on the public decision that sooner or later will be made as to where and how to dispose permanently of the waste presently at military weapons installations and that continues to accumulate at nuclear power stations. No final decision has yet been made. There is no clear precedent from other countries. The organization of state and federal studies is unique. The state studies involve more disciplines than any previous efforts. They have been carried out in parallel to federal studies and have pioneered in defining some problems and appropriate research methods. A recent annotated bibliography provides interested scientists with a compact guide to the 178 published reports, as well as to relevant journal articles and related documents.

White, G.F. [Univ. of Colorado, Boulder, CO (United States); Bronzini, M.S. [Oak Ridge National Lab., TN (United States); Colglazier, E.W. [National Academy of Sciences, Washington, DC (United States); Dohrenwend, B. [Columbia Univ., New York, NY (United States); Erikson, K. [Yale Univ., New Haven, CT (United States); Hansen, R. [Hansen Research, Winslow, WA (United States); Kneese, A.V. [Resources for the Future, Washington, DC (United States); Moore, R. [Richard Moore, Cheyenne, WY (United States); Page, E.B. [Bechtel, Inc., Washington, DC (United States); Rappaport, R.A. [Univ. of Michigan, Ann Arbor, MI (United States)

1994-11-08

348

Socioeconomic studies of high-level nuclear waste disposal.  

PubMed Central

The socioeconomic investigations of possible impacts of the proposed repository for high-level nuclear waste at Yucca Mountain, Nevada, have been unprecedented in several respects. They bear on the public decision that sooner or later will be made as to where and how to dispose permanently of the waste presently at military weapons installations and that continues to accumulate at nuclear power stations. No final decision has yet been made. There is no clear precedent from other countries. The organization of state and federal studies is unique. The state studies involve more disciplines than any previous efforts. They have been carried out in parallel to federal studies and have pioneered in defining some problems and appropriate research methods. A recent annotated bibliography provides interested scientists with a compact guide to the 178 published reports, as well as to relevant journal articles and related documents. PMID:7971963

White, G F; Bronzini, M S; Colglazier, E W; Dohrenwend, B; Erikson, K; Hansen, R; Kneese, A V; Moore, R; Page, E B; Rappaport, R A

1994-01-01

349

High-Level Language Production in Parkinson's Disease: A Review  

PubMed Central

This paper discusses impairments of high-level, complex language production in Parkinson's disease (PD), defined as sentence and discourse production, and situates these impairments within the framework of current psycholinguistic theories of language production. The paper comprises three major sections, an overview of the effects of PD on the brain and cognition, a review of the literature on language production in PD, and a discussion of the stages of the language production process that are impaired in PD. Overall, the literature converges on a few common characteristics of language production in PD: reduced information content, impaired grammaticality, disrupted fluency, and reduced syntactic complexity. Many studies also document the strong impact of differences in cognitive ability on language production. Based on the data, PD affects all stages of language production including conceptualization and functional and positional processing. Furthermore, impairments at all stages appear to be exacerbated by impairments in cognitive abilities. PMID:21860777

Altmann, Lori J. P.; Troche, Michelle S.

2011-01-01

350

High-level waste tank farm set point document  

SciTech Connect

Setpoints for nuclear safety-related instrumentation are required for actions determined by the design authorization basis. Minimum requirements need to be established for assuring that setpoints are established and held within specified limits. This document establishes the controlling methodology for changing setpoints of all classifications. The instrumentation under consideration involve the transfer, storage, and volume reduction of radioactive liquid waste in the F- and H-Area High-Level Radioactive Waste Tank Farms. The setpoint document will encompass the PROCESS AREA listed in the Safety Analysis Report (SAR) (DPSTSA-200-10 Sup 18) which includes the diversion box HDB-8 facility. In addition to the PROCESS AREAS listed in the SAR, Building 299-H and the Effluent Transfer Facility (ETF) are also included in the scope.

Anthony, J.A. III

1995-01-15

351

Midwestern High-Level Radioactive Waste Transportation Project  

SciTech Connect

For more than half a century, the Council of State Governments has served as a common ground for the states of the nation. The Council is a nonprofit, state-supported and -directed service organization that provides research and resources, identifies trends, supplies answers and creates a network for legislative, executive and judicial branch representatives. This List of Available Resources was prepared with the support of the US Department of Energy, Cooperative Agreement No. DE-FC02-89CH10402. However, any opinions, findings, conclusions, or recommendations expressed herein are those of the author(s) and do not necessarily reflect the views of DOE. The purpose of the agreement, and reports issued pursuant to it, is to identify and analyze regional issues pertaining to the transportation of high-level radioactive waste and to inform Midwestern state officials with respect to technical issues and regulatory concerns related to waste transportation.

Dantoin, T.S.

1990-12-01

352

Characterization of composite ceramic high level waste forms.  

SciTech Connect

Argonne National Laboratory has developed a composite ceramic waste form for the disposition of high level radioactive waste produced during electrometallurgical conditioning of spent nuclear fuel. The electrorefiner LiCl/KCl eutectic salt, containing fission products and transuranics in the chloride form, is contacted with a zeolite material which removes the fission products from the salt. After salt contact, the zeolite is mixed with a glass binder. The zeolite/glass mixture is then hot isostatic pressed (HIPed) to produce the composite ceramic waste form. The ceramic waste form provides a durable medium that is well suited to incorporate fission products and transuranics in the chloride form. Presented are preliminary results of the process qualification and characterization studies, which include chemical and physical measurements and product durability testing, of the ceramic waste form.

Frank, S. M.; Bateman, K. J.; DiSanto, T.; Johnson, S. G.; Moschetti, T. L.; Noy, M. H.; O'Holleran, T. P.

1997-12-05

353

High Level Waste System Impacts from Acid Dissolution of Sludge  

SciTech Connect

This research evaluates the ability of OLI{copyright} equilibrium based software to forecast Savannah River Site High Level Waste system impacts from oxalic acid dissolution of Tank 1-15 sludge heels. Without further laboratory and field testing, only the use of oxalic acid can be considered plausible to support sludge heel dissolution on multiple tanks. Using OLI{copyright} and available test results, a dissolution model is constructed and validated. Material and energy balances, coupled with the model, identify potential safety concerns. Overpressurization and overheating are shown to be unlikely. Corrosion induced hydrogen could, however, overwhelm the tank ventilation. While pH adjustment can restore the minimal hydrogen generation, resultant precipitates will notably increase the sludge volume. OLI{copyright} is used to develop a flowsheet such that additional sludge vitrification canisters and other negative system impacts are minimized. Sensitivity analyses are used to assess the processability impacts from variations in the sludge/quantities of acids.

KETUSKY, EDWARD

2006-04-20

354

A High School Project Seminar on Sea Level Rise  

NASA Astrophysics Data System (ADS)

In Bavaria the curriculum of the upper grade of high school includes a so called project seminar, running over one and a half year. The aims of the seminar are to let the pupils learn to work on a specific topic, to organize themselves in a team, to improve their soft skills and become familiar with the working life. The topic of the project seminar, jointly organized by the Bertold-Brecht-Gymnasium in Munich and the Deutsche Geodätische Forschungsinstitut (DGFI) was on the "Global sea level rise". A team of 13 pupils computed the mean sea level rise by using on the one hand altimetry data of TOPEX, Jason-1 and Jason2 and on the other hand data of globally distributed tide gauges, corrected for vertical crustal movements derived from GPS products. The results of the two independent approaches were compared with each other and discussed considering also statements and discussions found in press, TV, and the web. Finally, a presentation was prepared and presented at school.

Seitz, M.; Bosch, W.

2012-04-01

355

PLUTONIUM/HIGH-LEVEL VITRIFIED WASTE BDBE DOSE CALCULATION  

SciTech Connect

The purpose of this calculation is to provide a dose consequence analysis of high-level waste (HLW) consisting of plutonium immobilized in vitrified HLW to be handled at the proposed Monitored Geologic Repository at Yucca Mountain for a beyond design basis event (BDBE) under expected conditions using best estimate values for each calculation parameter. In addition to the dose calculation, a plutonium respirable particle size for dose calculation use is derived. The current concept for this waste form is plutonium disks enclosed in cans immobilized in canisters of vitrified HLW (i.e., glass). The plutonium inventory at risk used for this calculation is selected from Plutonium Immobilization Project Input for Yucca Mountain Total Systems Performance Assessment (Shaw 1999). The BDBE examined in this calculation is a nonmechanistic initiating event and the sequence of events that follow to cause a radiological release. This analysis will provide the radiological releases and dose consequences for a postulated BDBE. Results may be considered in other analyses to determine or modify the safety classification and quality assurance level of repository structures, systems, and components. This calculation uses best available technical information because the BDBE frequency is very low (i.e., less than 1.0E-6 events/year) and is not required for License Application for the Monitored Geologic Repository. The results of this calculation will not be used as part of a licensing or design basis.

J.A. Ziegler

2000-11-20

356

THE HIGH-ENERGY IMPULSIVE GROUND-LEVEL ENHANCEMENT  

SciTech Connect

We have studied short-lived (21 minute average duration), highly anisotropic pulses of cosmic rays that constitute the first phase of 10 large ground-level enhancements (GLEs), and which extend to rigidities in the range 5-20 GV. We provide a set of constraints that must be met by any putative acceleration mechanism for this type of solar-energetic-particle (SEP) event. The pulses usually have very short rise-times (three to five minutes) at all rigidities, and exhibit the remarkable feature that the intensity drops precipitously by 50% to 70% from the maximum within another three to five minutes. Both the rising and falling phases exhibit velocity dispersion, which indicates that there are particles with rigidities in the range 1 < P (GV) < 3 in the beam, and the evidence is that there is little scattering en route from the Sun. We name these events the high-energy impulsive ground-level enhancement (HEI GLE). We argue that the time-dependence observed at Earth at {approx}5 GV is a close approximation to that of the SEP pulse injected into the open heliospheric magnetic field in the vicinity of the Sun. We conclude that the temporal characteristics of the HEI GLE impose nine constraints on any putative acceleration process. Two of the HEI GLEs are preceded by short-lived, fast-rising neutron and >90 MeV gamma-ray bursts, indicating that freshly accelerated SEPs had impinged on higher-density matter in the chromosphere prior to the departure of the SEP pulse for Earth. This study was based on an updated archive of the 71 GLEs in the historic record, which is now available for public use.

McCracken, K. G. [Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742 (United States); Moraal, H. [Centre for Space Research, School for Physical and Chemical Sciences, North-West University, Potchefstroom 2520 (South Africa); Shea, M. A. [CSPAR, University of Alabama at Huntsville, Huntsville, AL 35899 (United States)

2012-12-20

357

Enclosure 3 DOE Response to EPA Question Regarding "High-Level Liquid Radioactive Waste"  

E-print Network

Enclosure 3 DOE Response to EPA Question Regarding "High-Level Liquid Radioactive Waste" Subsequent regarding "high-level liquid radioactive waste". As stated in the body of the letter the solid wastes defining High Level Waste: For the purpose of this statement of policy, "high-level liquid radioactive

358

Gravity model studies of Newberry Volcano, Oregon  

SciTech Connect

Newberry, Volcano, a large Quaternary volcano located about 60 km east of the axis of the High Cascades volcanoes in central Oregon, has a coincident positive residual gravity anomaly of about 12 mGals. Model calculations of the gravity anomaly field suggest that the volcano is underlain by an intrusive complex of mafic composition of about 20-km diameter and 2-km thickness, at depths above 4 km below sea level. However, uplifted basement in a northwest trending ridge may form part of the underlying excess mass, thus reducing the volume of the subvolcanic intrusive. A ring dike of mafic composition is inferred to intrude to near-surface levels along the caldera ring fractures, and low-density fill of the caldera floor probably has a thickness of 0.7--0.9 km. The gravity anomaly attributable to the volcano is reduced to the east across a north-northwest trending gravity anomaly gradient through Newberry caldera and suggests that normal, perhaps extensional, faulting has occurred subsequent to caldera formation and may have controlled the location of some late-stage basaltic and rhyolitic eruptions. Significant amounts of felsic intrusive material may exist above the mafic intrusive zone but cannot be resolved by the gravity data.

Gettings, M.E.; Griscom, A.

1988-09-10

359

Increased levels of UV-induced protease activity in human UVAP-1 cells exposed to gravity-changing stress: involvement of E-64-sensitive proteases in suppression of UV mutagenicity.  

PubMed

Under the 1G condition, the increase in antipain-sensitive protease activity promptly after UV (mainly 254 nm wavelength) irradiation in cultured human cells is detected and found to be one of the intriguing events involved in suppression of cell mutability. It was found that two cell lines, RSa and its variant UVAP-1 cells are applicable; the former is hypermutable and not susceptible to protease activation, while the latter is hypomutable and susceptible. In the present study it was investigated whether the increase in protease activity by UV irradiation is also observed in hypomutable human UVAP-1 cells exposed to gravity-changing stress and whether the increase is involved in suppression of UV mutagenicity. Exposure of human UVAP-1 cells to gravity-changing stress such as free-fall and parabolic flight prior to UV irradiation resulted in a pronounced increase in protease activity, but not to hypergravity conditions (2 and 10G) prior to UV irradiation. To characterize the proteases, components of lysates from the cells exposed to free-fall prior to UV irradiation were fractionated by high performance liquid chromatography, indicating two separate fractions with highly increased levels of E-64-sensitive protease activity. In the cells treated with E-64 during their exposure to free-fall, K-ras codon 12 base substitution mutation was detected after UV irradiation, although the mutation was not detected after UV irradiation alone. Thus, the increase in E-64-sensitive protease activity may be involved in the suppression of UV mutagenicity in UVAP-1 cells exposed to free-fall. PMID:12713800

Takahashi, Shunji; Zhang, Hong-Chang; Hasegawa, Ritsuko; Karata, Kiyonobu; Kita, Kazuko; Wano, Chieko; Yamaguchi, Yoshitaka; Sugaya, Shigeru; Nomura, Jun; Ichinose, Masaharu; Suzuki, Nobuo

2003-01-01

360

Dual gravity and E11  

E-print Network

We consider the equation of motion in the gravity sector that arises from the non-linear realisation of the semi-direct product of E11 and its first fundamental representation, denoted by l1, in four dimensions. This equation is first order in derivatives and at low levels relates the usual field of gravity to a dual gravity field. When the generalised space-time is restricted to be the usual four dimensional space-time we show that this equation does correctly describe Einstein's theory at the linearised level. We also comment on previous discussions of dual gravity.

Peter West

2014-11-04

361

Control of high level radioactive waste-glass melters  

SciTech Connect

Slurry Fed Melters (SFM) are being developed in the United States, Europe and Japan for the conversion of high-level radioactive waste to borosilicate glass for permanent disposal. The high transition metal, noble metal, nitrate, organic, and sulfate contents of these wastes lead to unique melter redox control requirements. Pilot waste-glass melter operations have indicated the possibility of nickel sulfide or noble-metal fission-product accumulation on melter floors, which can lead to distortion of electric heating patterns, and decrease melter life. Sulfide formation is prevented by control of the redox chemistry of the melter feed. The redox state of waste-glass melters is determined by balance between the reducing potential of organic compounds in the feed, and the oxidizing potential of gases above the melt, and nitrates and polyvalent elements in the waste. Semiquantitative models predicting limitations of organic content have been developed based on crucible testing. Computerized thermodynamic computations are being developed to predict the sequence and products of redox reactions and is assessing process variations. Continuous melter test results have been compared to improved computer staged-thermodynamic-models of redox behavior. Feed chemistry control to prevent sulfide and moderate noble metal accumulations are discussed. 17 refs., 3 figs.

Bickford, D.F.; Choi, A.S.

1991-01-01

362

Interactions between Artificial Gravity, the Affected Physiological Systems, and Nutrition  

NASA Technical Reports Server (NTRS)

Malnutrition, either by insufficient supply of some nutrients or by overfeeding, has a profound effect on the health of an organism. Therefore, optimal nutrition is a necessity in normal gravity on Earth, in microgravity, and when applying artificial gravity to the human system. Reduced physical activity, such as observed in microgravity or bed rest, has an effect on many physiological systems, such as the cardiovascular, musculoskeletal, immune, and body fluids regulation systems. There is currently no countermeasure that is effective to counteract both the cardiovascular and musculoskeletal deconditioning when applied for a short duration (see Chapter 1). Artificial gravity therefore seems the simplest physiological approach to keep these systems intact. The application of intermittent daily dose of artificial gravity by means of centrifugation has often been proposed as a potential countermeasure against the physiological deconditioning induced by spaceflight. However, neither the optimal gravity level, nor its optimal duration of exposure have been enough studied to recommend a validated, effective, and efficient artificial gravity application. As discussed in previous chapters, artificial gravity has a very high potential to counteract any changes caused by reduced physical activity. The nutrient supply, which ideally should match the actual needs, will interact with these changes and therefore has also to be taken into account. This chapter reviews the potential interactions between these nutrients (energy intake, vitamins, minerals) and the other physiological systems affected by artificial gravity generated by an on-board short-radius centrifuge.

Heer, Martina; Baecker, Nathalie; Zwart, Sara; Smith, Scott

2006-01-01

363

Effects of heat shock and ethanol stress on the viability of a Saccharomyces uvarum (carlsbergensis) brewing yeast strain during fermentation of high gravity wort  

Microsoft Academic Search

Summary The effects of heat shock and ethanol stress on the viability of a lager brewing yeast strain during fermentation of high gravity wort were studied. These stress effects resulted in reduced cell viability and inhibition of cell growth during fermentation. Cells were observed to be less tolerant to heat shock during the fermentation of 25°P (degree Plato) wort than

Joseph A. Odumeru; Tony D'Amore; Inge Russell; Graham G. Stewart

1992-01-01

364

Review of high-level waste form properties. [146 bibliographies  

SciTech Connect

This report is a review of waste form options for the immobilization of high-level-liquid wastes from the nuclear fuel cycle. This review covers the status of international research and development on waste forms as of May 1979. Although the emphasis in this report is on waste form properties, process parameters are discussed where they may affect final waste form properties. A summary table is provided listing properties of various nuclear waste form options. It is concluded that proposed waste forms have properties falling within a relatively narrow range. In regard to crystalline versus glass waste forms, the conclusion is that either glass of crystalline materials can be shown to have some advantage when a single property is considered; however, at this date no single waste form offers optimum properties over the entire range of characteristics investigated. A long-term effort has been applied to the development of glass and calcine waste forms. Several additional waste forms have enough promise to warrant continued research and development to bring their state of development up to that of glass and calcine. Synthetic minerals, the multibarrier approach with coated particles in a metal matrix, and high pressure-high temperature ceramics offer potential advantages and need further study. Although this report discusses waste form properties, the total waste management system should be considered in the final selection of a waste form option. Canister design, canister materials, overpacks, engineered barriers, and repository characteristics, as well as the waste form, affect the overall performance of a waste management system. These parameters were not considered in this comparison.

Rusin, J.M.

1980-12-01

365

Mixed gravity mode growth during directional dendritic solidification aboard the KC-135  

NASA Technical Reports Server (NTRS)

NASA's KC-135, which flies a cyclic parabolic route designed to furnish periods of low gravity alternating with periods of high gravity, has been used to directionally solidify a superalloy and a FE-C-Si alloy. Probable transient effects, due to the rapid changes in the gravity levels, must be taken into account. An effort is presently made to show that experimental design is especially critical in the case of dendritic directional solidification experiments in which mixed gravity modes occur; inappropriate design easily leads to anomalous structures and data.

Grugel, Richard N.

1989-01-01

366

Gravity, magnetic, and high-precision relocated seismicity profiles suggest a connection between the Hayward and Calaveras Faults, northern California  

NASA Astrophysics Data System (ADS)

Gravity, magnetic, and seismicity data profiled across the Hayward Fault Zone were generated as part of ongoing studies to help determine the geologic and tectonic setting of the San Francisco Bay region. These data, combined with previous geophysical studies that indicate that the Hayward Fault Zone dips 75°NE near San Leandro and follows a preexisting structure, reveal a possible direct connection between the seismogenic portion of the Hayward and Calaveras Faults at depth. Although the relocated seismicity data are regional in nature, they suggest that the dip of the Hayward Fault Zone may vary from near vertical in the northwestern part of the fault to about 75°NE at San Leandro in the central part of the fault to about 50°NE in the southeastern part of the fault. Gravity and magnetic data, profiled across the Hayward Fault Zone, were processed using standard geophysical techniques. Cross sections of high-precision relocated hypocenters were constructed along each profile from the northwestern to the southeastern end of the Hayward Fault Zone. Profiles and cross sections are referenced to Pinole Point, where the Hayward Fault enters San Pablo Bay, and are spaced 2.5 km apart. Topographic profiles shown on the seismicity cross sections were generated using U.S. Geological Survey (USGS) 7.5-min, 30-m digital elevation models. Relocation of seismicity data was accomplished using a regional double-difference method. The double-difference method incorporates ordinary travel time measurements and cross correlation of P and S wave differential travel time measurements. Relative locations between earthquakes have hypocentral errors of about 100 m horizontally and 250 m vertically. Absolute location uncertainties were not determined but are probably dramatically improved compared to the USGS's Northern California Seismic Network catalog data.

Ponce, D. A.; Simpson, R. W.; Graymer, R. W.; Jachens, R. C.

2004-07-01

367

Regeneration of eye tissues is modulated by altered levels of gravity at 1g, 2g, and in microgravity during spaceflight  

NASA Astrophysics Data System (ADS)

The pursuit of human space exploration requires detailed knowledge of microgravity-related changes in fundamental biological processes, and their effects on health. Normal regeneration of organs and tissues is one such fundamental process that allows maintenance of vitality and function of living organisms. Animal models of tissue regeneration include the newt (Pleurodeles waltl, Urodela) eye, which has been extensively used by our team in Russian Bion and Foton microgravity experiments since 1985, and in recent NASA 2.5 meter diameter centrifuge hypergravity experiments. In total, these experiments allow us to draw several broad conclusions: Newt lens regeneration is significantly altered in microgravity and hypergravity relative to 1g controls. Lenses formed in microgravity are larger and more developed than those regenerated in 1g controls; Microgravity alterations of lens regeneration can persist after spaceflight, and continue to affect repeated removal and regeneration of the lens after return to 1g; Microgravity increases the numbers of early stage regenerative proliferating BrdU-labeled cells in dorsal iris progenitors and in the lens regenerate. Regeneration under hypergravity conditions at 2g inhibits lens regeneration, and often causes retinal detachment. Molecular mechanisms regulating lens regeneration rate include FGF2 signaling, (a key pathway for eye tissue development and regeneration), and an expression of stress-related proteins - HSPs. In conclusion, regeneration of lens and other eye tissues in the newt is sensitive to, and regulated by the level of gravity mechanotransduction and developmental signaling pathways, with microgravity favoring stem cell progenitor proliferation, and gravity at 1g promoting terminal differentiation, while hypergravity at 2g often causes damage of delicate regenerating tissues.

Grigoryan, Eleonora; Almeida, Eduardo; Mitashov, Victor

368

Spectral analysis of highly aliased sea-level signals  

NASA Astrophysics Data System (ADS)

Observing high-wavenumber ocean phenomena with a satellite altimeter generally calls for "along-track" analyses of the data: measurements along a repeating satellite ground track are analyzed in a point-by-point fashion, as opposed to spatially averaging data over multiple tracks. The sea-level aliasing problems encountered in such analyses can be especially challenging. For TOPEX/POSEIDON, all signals with frequency greater than 18 cycles per year (cpy), including both tidal and subdiurnal signals, are folded into the 0-18 cpy band. Because the tidal bands are wider than 18 cpy, residual tidal cusp energy, plus any subdiurnal energy, is capable of corrupting any low-frequency signal of interest. The practical consequences of this are explored here by using real sea-level measurements from conventional tide gauges, for which the true oceanographic spectrum is known and to which a simulated "satellite-measured" spectrum, based on coarsely subsampled data, may be compared. At many locations the spectrum is sufficently red that interannual frequencies remain unaffected. Intra-annual frequencies, however, must be interpreted with greater caution, and even interannual frequencies can be corrupted if the spectrum is flat. The results also suggest that whenever tides must be estimated directly from the altimetry, response methods of analysis are preferable to harmonic methods, even in nonlinear regimes; this will remain so for the foreseeable future. We concentrate on three example tide gauges: two coastal stations on the Malay Peninsula where the closely aliased K1 and Ssa tides are strong and at Canton Island where trapped equatorial waves are aliased.

Ray, Richard D.

1998-10-01

369

High level expression and purification of HhaI methyltransferase.  

PubMed Central

A cloning system for the DNA-(cytosine-5)-methyltransferase MHhaI and high level expression of the enzyme are described. A parent plasmid was constructed from fragments of the MHhaI gene and synthetic oligonucleotides. The construct permits introduction of various restriction sites for cloning at precise positions near the initiation codon, and beyond the termination codon. The entire MHhaI coding sequence was introduced as a 1042 b.p. NdeI-XbaI fragment into the vector pAR3040 which contains the T7 RNA polymerase promoter. The resultant plasmid pTNX3 (MHhaI-pAR3040) was introduced into McrB- E. coli strains HB101 and GM2929, and expression of MHhaI was induced by infection with the lambda phage CE6 carrying the T7 RNA polymerase gene. In induced cells, catalytically active MHhaI was produced at a level that corresponds to about 8% of the total soluble protein; an insoluble form of the protein was also formed, but could be readily removed. The expressed soluble enzyme from HB101/pTNX3 was purified to apparent homogeneity in about 50% yield by a two-step chromatographic procedure involving DEAE-cellulose and Heparin-Sepharose; a one liter culture gave about 2.5 mg of pure enzyme. The molecular weight and kinetic properties of the expressed protein are identical to those reported for the authentic MHhaI, and its amino terminal sequence agrees with that predicted from the DNA sequence. Images PMID:3340551

Wu, J C; Santi, D V

1988-01-01

370

Spent nuclear fuel project high-level information management plan  

SciTech Connect

This document presents the results of the Spent Nuclear Fuel Project (SNFP) Information Management Planning Project (IMPP), a short-term project that identified information management (IM) issues and opportunities within the SNFP and outlined a high-level plan to address them. This high-level plan for the SNMFP IM focuses on specific examples from within the SNFP. The plan`s recommendations can be characterized in several ways. Some recommendations address specific challenges that the SNFP faces. Others form the basis for making smooth transitions in several important IM areas. Still others identify areas where further study and planning are indicated. The team`s knowledge of developments in the IM industry and at the Hanford Site were crucial in deciding where to recommend that the SNFP act and where they should wait for Site plans to be made. Because of the fast pace of the SNFP and demands on SNFP staff, input and interaction were primarily between the IMPP team and members of the SNFP Information Management Steering Committee (IMSC). Key input to the IMPP came from a workshop where IMSC members and their delegates developed a set of draft IM principles. These principles, described in Section 2, became the foundation for the recommendations found in the transition plan outlined in Section 5. Availability of SNFP staff was limited, so project documents were used as a basis for much of the work. The team, realizing that the status of the project and the environment are continually changing, tried to keep abreast of major developments since those documents were generated. To the extent possible, the information contained in this document is current as of the end of fiscal year (FY) 1995. Programs and organizations on the Hanford Site as a whole are trying to maximize their return on IM investments. They are coordinating IM activities and trying to leverage existing capabilities. However, the SNFP cannot just rely on Sitewide activities to meet its IM requirements. While the SNFP can use some work done Sitewide and by projects such as the Tank Waste Remediation System (TWRS), they will still need to make some IM investments of their own.

Main, G.C.

1996-09-13

371

Secondary arm coarsening and microsegregation in superalloy PWA-1480 single crystals: Effect of low gravity  

NASA Technical Reports Server (NTRS)

Single crystal specimens of nickel base superalloy PWA-1480 were directionally solidified on ground and during low gravity (20 sec) and high gravity (90 sec) parabolic maneuver of KC-135 aircraft. Thermal profiles were measured during solidification by two in-situ thermocouples positioned along the sample length. The samples were quenched during either high or low gravity cycles so as to freeze the structures of the mushy zone developing under different gravity levels. Microsegregation was measured by examining the solutal profiles on several transverse cross-sections across primary dendrites along their length in the quenched mushy zone. Effect of gravity level on secondary arm coarsening kinetics and microsegregation have been investigated. The results indicate that there is no appreciable difference in the microsegregation and coarsening kinetics behavior in the specimens grown under high or low gravity. This suggests that short duration changes in gravity/levels (0.02 to 1.7 g) do not influence convection in the interdendritic region. Examination of the role of natural convection, in the melt near the primary dendrite tips, on secondary arm spacings requires low gravity periods longer than presently available on KC-135. Secondary arm coarsening kinetics show a reasonable fit with the predictions from a simple analytical model proposed by Kirkwood for a binary alloy.

Vijayakumar, M.; Tewari, S. N.; Lee, J. E.; Curreri, P. A.

1990-01-01

372

High-level disinfection of gastrointestinal endoscope reprocessing.  

PubMed

High level disinfection (HLD) of the gastrointestinal (GI) endoscope is not simply a slogan, but rather is a form of experimental monitoring-based medicine. By definition, GI endoscopy is a semicritical medical device. Hence, such medical devices require major quality assurance for disinfection. And because many of these items are temperature sensitive, low-temperature chemical methods, such as liquid chemical germicide, must be used rather than steam sterilization. In summarizing guidelines for infection prevention and control for GI endoscopy, there are three important steps that must be highlighted: manual washing, HLD with automated endoscope reprocessor, and drying. Strict adherence to current guidelines is required because compared to any other medical device, the GI endoscope is associated with more outbreaks linked to inadequate cleaning or disinfecting during HLD. Both experimental evaluation on the surveillance bacterial cultures and in-use clinical results have shown that, the monitoring of the stringent processes to prevent and control infection is an essential component of the broader strategy to ensure the delivery of safe endoscopy services, because endoscope reprocessing is a multistep procedure involving numerous factors that can interfere with its efficacy. Based on our years of experience in the surveillance of culture monitoring of endoscopic reprocessing, we aim in this study to carefully describe what details require attention in the GI endoscopy disinfection and to share our experience so that patients can be provided with high quality and safe medical practices. Quality management encompasses all aspects of pre- and post-procedural care including the efficiency of the endoscopy unit and reprocessing area, as well as the endoscopic procedure itself. PMID:25699232

Chiu, King-Wah; Lu, Lung-Sheng; Chiou, Shue-Shian

2015-02-20

373

Studies of Mercury in High Level Waste Systems  

SciTech Connect

During nuclear weapons production, nuclear reactor target and fuel rods were processed in F- and H-Canyons. For the target rods, a caustic dissolution of the aluminum cladding was performed prior to nitric acid dissolution of the uranium metal targets in the large canyon dissolvers. To dissolve the aluminum cladding and the U-Al fuel, mercury in the form of soluble mercury (II) nitrate was added as a catalyst to accelerate the dissolution of the aluminum. F-Canyon began to process plutonium-containing residues that were packaged in aluminum cans and thus required the use of mercury as a dissolution catalyst. Following processing to remove uranium and plutonium using the solvent extraction process termed the Plutonium-Uranium Recovery by Extraction (PUREX) process, the acidic waste solutions containing fission products and other radionuclides were neutralized with sodium hydroxide. The mercury used in canyon processing is fractionated between the sludge and supernate that is transferred from the canyons to the tank farm. The sludge component of the waste is currently vitrified in the Defense Waste Processing Facility (DWPF). The vitrified waste canisters are to be sent to the federal repository for High Level Waste. The mercury in the sludge, presumably in an oxide or hydroxide form is reduced to elemental mercury by the chemical additions and high temperatures, steam stripped and collected in the Mercury Collection Tank. The mercury in the dilute supernate is in the form of mercuric ion and is soluble. During evaporation, the mercuric ion is reduced to elemental mercury, vaporizes into the overheads system and is collected as a metallic liquid in the Mercury Removal Tank.

Wilmarth, W.R.

2003-09-03

374

Deep borehole disposal of high-level radioactive waste.  

SciTech Connect

Preliminary evaluation of deep borehole disposal of high-level radioactive waste and spent nuclear fuel indicates the potential for excellent long-term safety performance at costs competitive with mined repositories. Significant fluid flow through basement rock is prevented, in part, by low permeabilities, poorly connected transport pathways, and overburden self-sealing. Deep fluids also resist vertical movement because they are density stratified. Thermal hydrologic calculations estimate the thermal pulse from emplaced waste to be small (less than 20 C at 10 meters from the borehole, for less than a few hundred years), and to result in maximum total vertical fluid movement of {approx}100 m. Reducing conditions will sharply limit solubilities of most dose-critical radionuclides at depth, and high ionic strengths of deep fluids will prevent colloidal transport. For the bounding analysis of this report, waste is envisioned to be emplaced as fuel assemblies stacked inside drill casing that are lowered, and emplaced using off-the-shelf oilfield and geothermal drilling techniques, into the lower 1-2 km portion of a vertical borehole {approx}45 cm in diameter and 3-5 km deep, followed by borehole sealing. Deep borehole disposal of radioactive waste in the United States would require modifications to the Nuclear Waste Policy Act and to applicable regulatory standards for long-term performance set by the US Environmental Protection Agency (40 CFR part 191) and US Nuclear Regulatory Commission (10 CFR part 60). The performance analysis described here is based on the assumption that long-term standards for deep borehole disposal would be identical in the key regards to those prescribed for existing repositories (40 CFR part 197 and 10 CFR part 63).

Stein, Joshua S.; Freeze, Geoffrey A.; Brady, Patrick Vane; Swift, Peter N.; Rechard, Robert Paul; Arnold, Bill Walter; Kanney, Joseph F.; Bauer, Stephen J.

2009-07-01

375

Cascading gravity is ghost free  

SciTech Connect

We perform a full perturbative stability analysis of the 6D cascading gravity model in the presence of 3-brane tension. We demonstrate that for sufficiently large tension on the (flat) 3-brane, there are no ghosts at the perturbative level, consistent with results that had previously only been obtained in a specific 5D decoupling limit. These results establish the cascading gravity framework as a consistent infrared modification of gravity.

Rham, Claudia de [Departement de Physique Theorique, Universite de Geneve, 24 Quai E. Ansermet, CH-1211 Geneve (Switzerland); Khoury, Justin [Center for Particle Cosmology, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6395 (United States); Tolley, Andrew J. [Perimeter Institute for Theoretical Physics, 31 Caroline St. N., Waterloo, ON, N2L 2Y5 (Canada)

2010-06-15

376

Cascading Gravity is Ghost Free  

E-print Network

We perform a full perturbative stability analysis of the 6D cascading gravity model in the presence of 3-brane tension. We demonstrate that for sufficiently large tension on the (flat) 3-brane, there are no ghosts at the perturbative level, consistent with results that had previously only been obtained in a specific 5D decoupling limit. These results establish the cascading gravity framework as a consistent infrared modification of gravity.

Claudia de Rham; Justin Khoury; Andrew J. Tolley

2010-06-24

377

Neuromuscular onset succession of high level gymnasts during dynamic leg acceleration phases on high bar.  

PubMed

In several athletic disciplines there is evidence that for generating the most effective acceleration of a specific body part the transfer of momentum should run in a "whip-like" consecutive succession of body parts towards the segment which shall be accelerated most effectively (e.g. the arm in throwing disciplines). This study investigated the question how this relates to the succession of neuromuscular activation to induce such "whip like" leg acceleration in sports like gymnastics with changed conditions concerning the body position and momentary rotational axis of movements (e.g. performing giant swings on high bar). The study demonstrates that during different long hang elements, performed by 12 high level gymnasts, the succession of the neuromuscular activation runs primarily from the bar (punctum fixum) towards the legs (punctum mobile). This demonstrates that the frequently used teaching instruction, first to accelerate the legs for a successful realization of such movements, according to a high level kinematic output, is contradictory to the neuromuscular input patterns, being used in high level athletes, realizing these skills with high efficiency. Based on these findings new approaches could be developed for more direct and more adequate teaching methods regarding to an earlier optimization and facilitation of fundamental movement requirements. PMID:23941901

von Laßberg, Christoph; Rapp, Walter; Mohler, Betty; Krug, Jürgen

2013-10-01

378

High level waste tank farm setpoint document. Revision 1  

SciTech Connect

Revision 1 modifies Attachment I of this Technical Report as a result of a meeting which was held Friday, January 27, 1994 between Maintenance, Work Control, and Engineering to discuss report contents. Upon completion of the meeting, the Flow Chart was edited accordingly. Attachment 2 is modified for clerical reasons. Setpoints for nuclear safety-related instrumentation are required for actions determined by the design authorization basis. Minimum requirements need to be established for assuring that setpoints are established and held within specified limits. This document establishes the controlling methodology for changing setpoints of all classifications. The instrumentation under consideration involve the transfer, storage, and volume reduction of radioactive liquid waste in the F- and H-Area High-Level Radioactive Waste Tank Fanns. The setpoint document (Appendix 2) will encompass the PROCESS AREA listed in the Safety Analysis Report (SAR) (DSTSA-200-10 Sup 18) which includes the diversion box HDB-8 facility. In addition to the PROCESS AREAS listed in the SAR, Building 299-H and the Effluent Transfer Facility (ETF) are also included in the scope.

Anthony, J.A. III

1995-01-31

379

Why consider subseabed disposal of high-level nuclear waste  

SciTech Connect

Large areas of the deep seabed warrant assessment as potential disposal sites for high-level radioactive waste because: (1) they are far from seismically and tectonically active lithospheric plate boundaries; (2) they are far from active or young volcanos; (3) they contain thick layers of very uniform fine-grained clays; (4) they are devoid of natural resources likely to be exploited in the forseeable future; (5) the geologic and oceanographic processes governing the deposition of sediments in such areas are well understood, and are remarkably insensitive to past oceanographic and climatic changes; and (6) sedmentary records of tens of millions of years of slow, uninterrupted deposition of fine grained clay support predictions of the future stability of such sites. Data accumulated to date on the permeability, ion-retardation properties, and mechanical strength of pelagic clay sediments indicate that they can act as a primary barrier to the escape of buried nuclides. Work in progress should determine within the current decade whether subseabed disposal is environmentally acceptable and technically feasible, as well as address the legal, political and social issues raised by this new concept.

Heath, G.R.; Hollister, C.D.; Anderson, D.R.; Leinen, M.

1980-01-01

380

Defense High-Level Waste Leaching Mechanisms Program. Final report  

SciTech Connect

The Defense High-Level Waste Leaching Mechanisms Program brought six major US laboratories together for three years of cooperative research. The participants reached a consensus that solubility of the leached glass species, particularly solubility in the altered surface layer, is the dominant factor controlling the leaching behavior of defense waste glass in a system in which the flow of leachant is constrained, as it will be in a deep geologic repository. Also, once the surface of waste glass is contacted by ground water, the kinetics of establishing solubility control are relatively rapid. The concentrations of leached species reach saturation, or steady-state concentrations, within a few months to a year at 70 to 90/sup 0/C. Thus, reaction kinetics, which were the main subject of earlier leaching mechanisms studies, are now shown to assume much less importance. The dominance of solubility means that the leach rate is, in fact, directly proportional to ground water flow rate. Doubling the flow rate doubles the effective leach rate. This relationship is expected to obtain in most, if not all, repository situations.

Mendel, J.E. (compiler)

1984-08-01

381

High-level simulation of JWST event-driven operations  

NASA Astrophysics Data System (ADS)

The James Webb Space Telescope (JWST) has an event-driven architecture: an onboard Observation Plan Executive (OPE) executes an Observation Plan (OP) consisting of a sequence of observing units (visits). During normal operations, ground action to update the OP is only expected to be necessary about once a week. This architecture is designed to tolerate uncertainty in visit duration, and occasional visit failures due to inability to acquire guide stars, without creating gaps in the observing timeline. The operations concept is complicated by the need for occasional scheduling of timecritical science and engineering visits that cannot tolerate much slippage without inducing gaps, and also by onboard momentum management. A prototype Python tool called the JWST Observation Plan Execution Simulator (JOPES) has recently been developed to simulate OP execution at a high level and analyze the response of the Observatory and OPE to both nominal and contingency scenarios. Incorporating both deterministic and stochastic behavior, JOPES has potential to be a powerful tool for several purposes: requirements analysis, system verification, systems engineering studies, and test data generation. It has already been successfully applied to a study of overhead estimation bias: whether to use conservative or average-case estimates for timing components that are inherently uncertain, such as those involving guide-star acquisition. JOPES is being enhanced to support interfaces to the operational Proposal Planning Subsystem (PPS) now being developed, with the objective of "closing the loop" between testing and simulation by feeding simulated event logs back into the PPS.

Henry, R.; Kinzel, W.

2012-09-01

382

THERMAL ANALYSIS OF GEOLOGIC HIGH-LEVEL RADIOACTIVE WASTE PACKAGES  

SciTech Connect

The engineering design of disposal of the high level waste (HLW) packages in a geologic repository requires a thermal analysis to provide the temperature history of the packages. Calculated temperatures are used to demonstrate compliance with criteria for waste acceptance into the geologic disposal gallery system and as input to assess the transient thermal characteristics of the vitrified HLW Package. The objective of the work was to evaluate the thermal performance of the supercontainer containing the vitrified HLW in a non-backfilled and unventilated underground disposal gallery. In order to achieve the objective, transient computational models for a geologic vitrified HLW package were developed by using a computational fluid dynamics method, and calculations for the HLW disposal gallery of the current Belgian geological repository reference design were performed. An initial two-dimensional model was used to conduct some parametric sensitivity studies to better understand the geologic system's thermal response. The effect of heat decay, number of co-disposed supercontainers, domain size, humidity, thermal conductivity and thermal emissivity were studied. Later, a more accurate three-dimensional model was developed by considering the conduction-convection cooling mechanism coupled with radiation, and the effect of the number of supercontainers (3, 4 and 8) was studied in more detail, as well as a bounding case with zero heat flux at both ends. The modeling methodology and results of the sensitivity studies will be presented.

Hensel, S.; Lee, S.

2010-04-20

383

EUVE GO Survey: High Levels of User Satisfaction  

NASA Astrophysics Data System (ADS)

This paper describes the results of a detailed customer survey of Guest Observers (GOs) for NASA's Extreme Ultraviolet Explorer (EUVE) astronomy satellite observatory. The purpose of the research survey was to (1) measure the levels of GO customer satisfaction with respect to EUVE observing services, and (2) compare the observing experiences of EUVE GOs with their experiences using other satellite observatories. This survey was conducted as a business research project -- part of the author's graduate work as an MBA candidate. A total sample of 38 respondents, from a working population of 101 "active" EUVE GOs, participated in this survey. The results, which provided a profile of the "typical" EUVE GO, showed in a statistically significant fashion that these GOs were more than satisfied with the available EUVE observing services. In fact, the sample GOs generally rated their EUVE observing experiences to be better than average as compared to their experiences as GOs on other missions. These relatively high satisfaction results are particularly pleasing to the EUVE Project which, given its significantly reduced staffing environment at U.C. Berkeley, has continued to do more with less. This paper outlines the overall survey process: the relevant background and previous research, the survey design and methodology, and the final results and their interpretation. The paper also points out some general limitations and weaknesses of the study, along with some recommended actions for the EUVE Project and for NASA in general. This work was funded by NASA/UCB Cooperative Agreement NCC5-138.

Stroozas, B. A.

2000-12-01

384

Potential for erosion corrosion of SRS high level waste tanks  

SciTech Connect

SRS high-level radioactive waste tanks will not experience erosion corrosion to any significant degree during slurry pump operations. Erosion corrosion in carbon steel structures at reported pump discharge velocities is dominated by electrochemical (corrosion) processes. Interruption of those processes, as by the addition of corrosion inhibitors, sharply reduces the rate of metal loss from erosion corrosion. The well-inhibited SRS waste tanks have a near-zero general corrosion rate, and therefore will be essentially immune to erosion corrosion. The experimental data on carbon steel erosion corrosion most relevant to SRS operations was obtained at the Hanford Site on simulated Purex waste. A metal loss rate of 2.4 mils per year was measured at a temperature of 102 C and a slurry velocity comparable to calculated SRS slurry velocities on ground specimens of the same carbon steel used in SRS waste tanks. Based on these data and the much lower expected temperatures, the metal loss rate of SRS tanks under waste removal and processing conditions should be insignificant, i.e. less than 1 mil per year.

Zapp, P.E.

1994-01-01

385

Application of SYNROC to high-level defense wastes  

SciTech Connect

The SYNROC method for immobilization of high-level nuclear reactor wastes is currently being applied to US defense wastes in tank storage at Savannah River, South Carolina. The minerals zirconolite, perovskite, and hollandite are used in SYNROC D formulations to immobilize fission products and actinides that comprise up to 10% of defense waste sludges and coexisting solutions. Additional phases in SYNROC D are nepheline, the host phase for sodium; and spinel, the host for excess aluminum and iron. Up to 70 wt % of calcined sludge can be incorporated with 30 wt % of SYNROC additives to produce a waste form consisting of 10% nepheline, 30% spinel, and approximately 20% each of the radioactive waste-bearing phases. Urea coprecipitation and spray drying/calcining methods have been used in the laboratory to produce homogeneous, reactive ceramic powders. Hot pressing and sintering at temperatures from 1000 to 1100/sup 0/C result in waste form products with greater than 97% of theoretical density. Hot isostatic pressing has recently been implemented as a processing alternative. Characterization of waste-form mineralogy has been done by means of XRD, SEM, and electron microprobe. Leaching of SYNROC D samples is currently being carried out. Assessment of radiation damage effects and physical properties of SYNROC D will commence in FY 81.

Tewhey, J.D.; Hoenig, C.L.; Newkirk, H.W.; Rozsa, R.B.; Coles, D.G.; Ryerson, F.J.

1981-01-01

386

Patients subject to high levels of coercion: staff's understanding.  

PubMed

Measures to keep staff and patients safe (containment) frequently involve coercion. A small proportion of patients is subject to a large proportion of containment use. To reduce the use of containment, we need a better understanding of the circumstances in which it is used and the understandings of patients and staff. Two sweeps were made of all the wards, spread over four hospital sites, in one large London mental health organization to identify patients who had been subject to high levels of containment in the previous two weeks. Data were then extracted from their case notes about their past history, current problem behaviours, and how they were understood by the patients involved and the staff. Nurses and consultant psychiatrists were interviewed to supplement the information from the case records. Twenty-six heterogeneous patients were identified, with many ages, genders, diagnoses, and psychiatric specialities represented. The main problem behaviours giving rise to containment use were violence and self-harm. The roots of the problem behaviours were to be found in severe psychiatric symptoms, cognitive difficulties, personality traits, and the implementation of the internal structure of the ward by staff. Staff's range and depth of understandings was limited and did not include functional analysis, defence mechanisms, specific cognitive assessment, and other potential frameworks. There is a need for more in-depth assessment and understanding of patients' problems, which may lead to additional ways to reduce containment use. PMID:24766171

Bowers, Len; Wright, Steve; Stewart, Duncan

2014-05-01

387

A pilot test of partitioning for the simulated highly saline high level waste  

SciTech Connect

It is a problem how to treat the highly saline high level waste (HLW). A partitioning process for HLW was developed at INET. The partitioning process includes the removal of actinides by TRPO extraction, the removal of Sr by crown ether extraction, and the removal of Cs by ion exchange. A 72-hour test was carried out in a pilot facility using the simulated HLW. Nd and Zr were used to simulate Am and Pu, respectively. The decontamination factors are >3000, >500, >1000, {approx}150 and {approx}94 for U, Nd, Zr, Sr and Cs, respectively. The results meet the requirement to change the highly saline HLW into a non-{alpha} and intermediate level waste. (authors)

Chen, Jing; Wang, Jianchen; Jing, Shan [Institute of Nuclear and New Energy Technology, Tsinghua University, P.O.Box 1021, Beijing 102201 (China)

2007-07-01

388

Process Design Concepts for Stabilization of High Level Waste Calcine  

SciTech Connect

The current baseline assumption is that packaging ¡§as is¡¨ and direct disposal of high level waste (HLW) calcine in a Monitored Geologic Repository will be allowed. The fall back position is to develop a stabilized waste form for the HLW calcine, that will meet repository waste acceptance criteria currently in place, in case regulatory initiatives are unsuccessful. A decision between direct disposal or a stabilization alternative is anticipated by June 2006. The purposes of this Engineering Design File (EDF) are to provide a pre-conceptual design on three low temperature processes under development for stabilization of high level waste calcine (i.e., the grout, hydroceramic grout, and iron phosphate ceramic processes) and to support a down selection among the three candidates. The key assumptions for the pre-conceptual design assessment are that a) a waste treatment plant would operate over eight years for 200 days a year, b) a design processing rate of 3.67 m3/day or 4670 kg/day of HLW calcine would be needed, and c) the performance of waste form would remove the HLW calcine from the hazardous waste category, and d) the waste form loadings would range from about 21-25 wt% calcine. The conclusions of this EDF study are that: (a) To date, the grout formulation appears to be the best candidate stabilizer among the three being tested for HLW calcine and appears to be the easiest to mix, pour, and cure. (b) Only minor differences would exist between the process steps of the grout and hydroceramic grout stabilization processes. If temperature control of the mixer at about 80„aC is required, it would add a major level of complexity to the iron phosphate stabilization process. (c) It is too early in the development program to determine which stabilizer will produce the minimum amount of stabilized waste form for the entire HLW inventory, but the volume is assumed to be within the range of 12,250 to 14,470 m3. (d) The stacked vessel height of the hot process vessels in the hydroceramic grout process (i.e., 21 m) appears to be about the same as that estimated by the Direct Cementitious Waste Process in 1998, for which a conceptual design was developed. Some of the conceptual design efforts in the 1998 study may be applicable to the stabilizer processes addressed in this EDF. (e) The gamma radiation fields near the process vessels handling HLW calcine would vary from a range of about 300-350 R/hr at a distance of 2.5 cm from the side of the vessels to a range of about 50-170 R/hr at a distance of 100 cm from the side of the vessels. The calculations were made for combined calcine, which was defined as the total HLW calcine inventory uniformly mixed. (f) The gamma radiation fields near the stabilized waste in canisters would range from about 25-170 R/hr at 2.5 cm from the side of the canister and 5-35 R/hr at 100 cm from the side of the canister, depending on the which bin set was the source of calcine.

T. R. Thomas; A. K. Herbst

2005-06-01

389

Engineering ?-amylase levels in wheat grain suggests a highly sophisticated level of carbohydrate regulation during development.  

PubMed

Wheat starch degradation requires the synergistic action of different amylolytic enzymes. Our spatio-temporal study of wheat ?-amylases throughout grain development shows that AMY3 is the most abundant isoform compared with the other known ?-amylases. Endosperm-specific over-expression of AMY3 resulted in an increase of total ?-amylase activity in harvested grains. Unexpectedly, increased activity did not have a significant impact on starch content or composition but led to an increase of soluble carbohydrate (mainly sucrose) in dry grain. In AMY3 overexpression lines (A3OE), germination was slightly delayed and triacylglycerol (TAG) content was increased in the endosperm of mature grain. Despite increased AMY3 transcript and protein content throughout grain development, alterations of ?-amylase activity and starch granule degradation were not detected until grain maturation, suggesting a post-translational inhibition of ?-amylase activity in the endosperm during the starch filling period. These findings show unexpected effects of a high level of ?-amylase on grain development and composition, notably in carbon partitioning and TAG accumulation, and suggest the presence of a hitherto unknown regulatory pathway during grain filling. PMID:25053646

Whan, Alex; Dielen, Anne-Sophie; Mieog, Jos; Bowerman, Andrew F; Robinson, Hannah M; Byrne, Keren; Colgrave, Michelle; Larkin, Philip J; Howitt, Crispin A; Morell, Matthew K; Ral, Jean-Philippe

2014-10-01

390

Engineering ?-amylase levels in wheat grain suggests a highly sophisticated level of carbohydrate regulation during development  

PubMed Central

Wheat starch degradation requires the synergistic action of different amylolytic enzymes. Our spatio-temporal study of wheat ?-amylases throughout grain development shows that AMY3 is the most abundant isoform compared with the other known ?-amylases. Endosperm-specific over-expression of AMY3 resulted in an increase of total ?-amylase activity in harvested grains. Unexpectedly, increased activity did not have a significant impact on starch content or composition but led to an increase of soluble carbohydrate (mainly sucrose) in dry grain. In AMY3 overexpression lines (A3OE), germination was slightly delayed and triacylglycerol (TAG) content was increased in the endosperm of mature grain. Despite increased AMY3 transcript and protein content throughout grain development, alterations of ?-amylase activity and starch granule degradation were not detected until grain maturation, suggesting a post-translational inhibition of ?-amylase activity in the endosperm during the starch filling period. These findings show unexpected effects of a high level of ?-amylase on grain development and composition, notably in carbon partitioning and TAG accumulation, and suggest the presence of a hitherto unknown regulatory pathway during grain filling. PMID:25053646

Whan, Alex; Dielen, Anne-Sophie; Mieog, Jos; Bowerman, Andrew F.; Robinson, Hannah M.; Byrne, Keren; Colgrave, Michelle; Larkin, Philip J.; Howitt, Crispin A.; Morell, Matthew K.; Ral, Jean-Philippe

2014-01-01

391

Burning experiments and late Paleozoic high O2 levels  

NASA Astrophysics Data System (ADS)

The Paleozoic rise of land plants brought about increased burial of organic matter and a resulting increase in atmospheric oxygen concentrations. Levels as high as 30-35% O2 may have been reached during the Permo-Carboniferous (Berner and Canfield, 1989; Berner, 2001). However, burning experiments based solely on paper (Watson, 1978) have challenged these results, the claim being that if the oxygen made up more than 25% of the atmosphere, the frequency and intensity of forest fires would increase sufficiently to prevent the continued existence of plant life. Thus, since plants have persisted, it is possible that fires served as a negative feedback against excessive oxygen levels. An initial study of Paleozoic wildfire behavior via thermogravimetric analysis (TGA) was conducted under ambient and enriched oxygen conditions to simulate present and ancient atmospheres. The tests focused on natural fuels, specifically tree leaves and wood, tree fern fibers, and sphagnum peat-moss, simulating Permo-Carboniferous upland and swampland ecosystems, respectively. Three conclusions are: (1) enriched oxygen increases the rate of mass loss during burning; (2) fuel chemistry (cellulose vs. lignin) influences burning patterns; and (3) in geometrically heterogeneous fuels, geometry affects burning rate significantly. Both geometrically and chemically, paper resists fire poorly; thus, we found that it loses its mass at lower temperatures than forest materials and is therefore a poor proxy for Paleozoic ecosystems. Further study of Paleozoic wildfire spread behavior is currently being conducted. Fires are lit using pine dowels, which allow for reproducible fuel density. Steady-state, one-dimensional flame-spread is measured with thermocouples anchored two inches above the fuel bed. Both oxygen concentration of the air supply to the fire and moisture content of the fuels are varied, as we suspect that these are two main controls of wildfire spread. Burning fuels of varying moisture contents is central to this study, for fuel moisture is a fire retardant that may offset the fire-enhancing effects of high oxygen conditions. Earliest preliminary results at low moisture show that, as expected, increasing oxygen concentration significantly increases the rate of fuel consumption. This is expressed as both an increase in the speed of the flame spread and the temperature of the flames. It was found that a 35% oxygen (balance nitrogen) gas mixture caused fire to spread at about five times the rate of a fire in ambient air. The fire in the high-oxygen gas mixture was roughly 1.3 times the temperature of the fire in ambient air. The current work is not intended to exactly represent forest ecosystems; rather, it is intended to establish an understanding of flame-spread behavior in natural fuels and future work will include fuels that better represent natural ecosystems such as those used in the TGA experimentation.

Wildman, R.; Essenhigh, R.; Berner, R.; Hickey, L.; Wildman, C.

2003-04-01

392

Reusable, Extensible High-Level Data-Distribution Concept  

NASA Technical Reports Server (NTRS)

A framework for high-level specification of data distributions in data-parallel application programs has been conceived. [As used here, distributions signifies means to express locality (more specifically, locations of specified pieces of data) in a computing system composed of many processor and memory components connected by a network.] Inasmuch as distributions exert a great effect on the performances of application programs, it is important that a distribution strategy be flexible, so that distributions can be adapted to the requirements of those programs. At the same time, for the sake of productivity in programming and execution, it is desirable that users be shielded from such error-prone, tedious details as those of communication and synchronization. As desired, the present framework enables a user to refine a distribution type and adjust it to optimize the performance of an application program and conceals, from the user, the low-level details of communication and synchronization. The framework provides for a reusable, extensible, data-distribution design, denoted the design pattern, that is independent of a concrete implementation. The design pattern abstracts over coding patterns that have been found to be commonly encountered in both manually and automatically generated distributed parallel programs. The following description of the present framework is necessarily oversimplified to fit within the space available for this article. Distributions are among the elements of a conceptual data-distribution machinery, some of the other elements being denoted domains, index sets, and data collections (see figure). Associated with each domain is one index set and one distribution. A distribution class interface (where "class" is used in the object-oriented-programming sense) includes operations that enable specification of the mapping of an index to a unit of locality. Thus, "Map(Index)" specifies a unit, while "LocalLayout(Index)" specifies the local address within that unit. The distribution class can be extended to enable specification of commonly used distributions or novel user-defined distributions. A data collection can be defined over a domain. The term "data collection" in this context signifies, more specifically, an abstraction of mappings from index sets to variables. Since the index set is distributed, the addresses of the variables are also distributed.

James, Mark; Zima, Hans; Diaconescua, Roxana

2007-01-01

393

JET MIXING ANALYSIS FOR SRS HIGH-LEVEL WASTE RECOVERY  

SciTech Connect

The process of recovering the waste in storage tanks at the Savannah River Site (SRS) typically requires mixing the contents of the tank to ensure uniformity of the discharge stream. Mixing is accomplished with one to four slurry pumps located within the tank liquid. The slurry pump may be fixed in position or they may rotate depending on the specific mixing requirements. The high-level waste in Tank 48 contains insoluble solids in the form of potassium tetraphenyl borate compounds (KTPB), monosodium titanate (MST), and sludge. Tank 48 is equipped with 4 slurry pumps, which are intended to suspend the insoluble solids prior to transfer of the waste to the Fluidized Bed Steam Reformer (FBSR) process. The FBSR process is being designed for a normal feed of 3.05 wt% insoluble solids. A chemical characterization study has shown the insoluble solids concentration is approximately 3.05 wt% when well-mixed. The project is requesting a Computational Fluid Dynamics (CFD) mixing study from SRNL to determine the solids behavior with 2, 3, and 4 slurry pumps in operation and an estimate of the insoluble solids concentration at the suction of the transfer pump to the FBSR process. The impact of cooling coils is not considered in the current work. The work consists of two principal objectives by taking a CFD approach: (1) To estimate insoluble solids concentration transferred from Tank 48 to the Waste Feed Tank in the FBSR process and (2) To assess the impact of different combinations of four slurry pumps on insoluble solids suspension and mixing in Tank 48. For this work, several different combinations of a maximum of four pumps are considered to determine the resulting flow patterns and local flow velocities which are thought to be associated with sludge particle mixing. Two different elevations of pump nozzles are used for an assessment of the flow patterns on the tank mixing. Pump design and operating parameters used for the analysis are summarized in Table 1. The baseline pump orientations are chosen by the previous work [Lee et. al, 2008] and the initial engineering judgement for the conservative flow estimate since the modeling results for the other pump orientations are compared with the baseline results. As shown in Table 1, the present study assumes that each slurry pump has 900 gpm flowrate for the tank mixing analysis, although the Standard Operating Procedure for Tank 48 currently limits the actual pump speed and flowrate to a value less than 900 gpm for a 29 inch liquid level. Table 2 shows material properties and weight distributions for the solids to be modeled for the mixing analysis in Tank 48.

Lee, S.

2011-07-05

394

Qualification of Innovative High Level Waste Pipeline Unplugging Technologies  

SciTech Connect

In the past, some of the pipelines have plugged during high level waste (HLW) transfers resulting in schedule delays and increased costs. Furthermore, pipeline plugging has been cited by the 'best and brightest' technical review as one of the major issues that can result in unplanned outages at the Waste Treatment Plant causing inconsistent operation. As the DOE moves toward a more active high level waste retrieval, the site engineers will be faced with increasing cross-site pipeline waste slurry transfers that will result in increased probability of a pipeline getting plugged. Hence, availability of a pipeline unplugging tool/technology is crucial to ensure smooth operation of the waste transfers and in ensuring tank farm cleanup milestones are met. FIU had earlier tested and evaluated various unplugging technologies through an industry call. Based on mockup testing, two technologies were identified that could withstand the rigors of operation in a radioactive environment and with the ability to handle sharp 90 elbows. We present results of the second phase of detailed testing and evaluation of pipeline unplugging technologies and the objective is to qualify these pipeline unplugging technologies for subsequent deployment at a DOE facility. The current phase of testing and qualification comprises of a heavily instrumented 3-inch diameter (full-scale) pipeline facilitating extensive data acquisition for design optimization and performance evaluation, as it applies to three types of plugs atypical of the DOE HLW waste. Furthermore, the data from testing at three different lengths of pipe in conjunction with the physics of the process will assist in modeling the unplugging phenomenon that will then be used to scale-up process parameters and system variables for longer and site typical pipe lengths, which can extend as much as up to 19,000 ft. Detailed information resulting from the testing will provide the DOE end-user with sufficient data and understanding of the technology, and its limitations to aid in the benefit-cost analysis for management decision whether to deploy the technology or to abandon the pipeline as has been done in the past. In conclusion: The ultimate objective of this study is to qualify NuVision's unplugging technology for use at Hanford. Experimental testing has been conducted using three pipeline lengths and three types of blockages. Erosion rates have been obtained and pressure data is being analyzed. An amplification of the inlet pressure has been observed along the pipeline and is the key to determining up to what pipe lengths the technology can be used without surpassing the site pressure limit. In addition, we will attempt to establish what the expected unplugging rates will be at the longer pipe lengths for each of the three blockages tested. Detailed information resulting from the testing will provide the DOE end-user with sufficient data and understanding of the technology, and its limitations so that management decisions can be made whether the technology has a reasonable chance to successfully unplug a pipeline, such as a cross site transfer line or process transfer pipeline at the Waste Treatment Plant. (authors)

McDaniel, D.; Gokaltun, S.; Varona, J.; Awwad, A.; Roelant, D.; Srivastava, R. [Applied Research Center, Florida International University, Miami, FL (United States)

2008-07-01

395

HIGH LEVEL WASTE SLUDGE BATCH 4 VARIABILITY STUDY  

SciTech Connect

The Defense Waste Processing Facility (DWPF) is preparing for vitrification of High Level Waste (HLW) Sludge Batch 4 (SB4) in early FY2007. To support this process, the Savannah River National Laboratory (SRNL) has provided a recommendation to utilize Frit 503 for vitrifying this sludge batch, based on the composition projection provided by the Liquid Waste Organization on June 22, 2006. Frit 418 was also recommended for possible use during the transition from SB3 to SB4. A critical step in the SB4 qualification process is to demonstrate the applicability of the durability models, which are used as part of the DWPF's process control strategy, to the glass system of interest via a variability study. A variability study is an experimentally-driven assessment of the predictability and acceptability of the quality of the vitrified waste product that is anticipated from the processing of a sludge batch. At the DWPF, the durability of the vitrified waste product is not directly measured. Instead, the durability is predicted using a set of models that relate the Product Consistency Test (PCT) response of a glass to the chemical composition of that glass. In addition, a glass sample is taken during the processing of that sludge batch, the sample is transmitted to SRNL, and the durability is measured to confirm acceptance. The objective of a variability study is to demonstrate that these models are applicable to the glass composition region anticipated during the processing of the sludge batch - in this case the Frit 503 - SB4 compositional region. The success of this demonstration allows the DWPF to confidently rely on the predictions of the durability/composition models as they are used in the control of the DWPF process.

Fox, K; Tommy Edwards, T; David Peeler, D; David Best, D; Irene Reamer, I; Phyllis Workman, P

2006-10-02

396

Seasonal changes in stress indicators in high level football.  

PubMed

This study aimed at describing changes in stress and performance indicators throughout a competitive season in high level football. 15 players (19.5±3.0 years, 181±5 cm, 75.7±9.0 kg) competing under professional circumstances were tested at baseline and 3 times during the season 2008/09 (in-season 1, 2, 3). Testing consisted of the Recovery-Stress Questionnaire for Athletes (Total Stress and Recovery score), vertical jump tests (counter movement and drop jump (DJ)), and a maximal ramp-like running test. Average match exposure was higher during a 3-weeks period prior to in-season 3 compared to in-season 1 and 2 (1.5 vs. 1 h/week, p=0.05). Total Stress score was elevated at in-season 1 and 2 compared to baseline (p<0.01) with a further increase at in-season 3 (p<0.03; generalized eta squared (?(2)(g))=0.37). Total Recovery score was decreased at in-season 1 and 3 compared to baseline (p<0.05; ?(2)(g)=0.21). Maximal running velocity (V(max)) and jumping heights were not significantly affected (?(2)(g)?0.04). Changes in DJ height and V (max) between baseline and in-season 3 were correlated with the corresponding changes in Total Stress score (r=-0.55 and r=-0.61, p<0.03). Usual match exposure during a professional football season does not induce relevant changes in performance indicators. Accumulated stress and a lack of recovery towards the end of a season might be indicated by psychometric deteriorations. PMID:21271495

Faude, O; Kellmann, M; Ammann, T; Schnittker, R; Meyer, T

2011-04-01

397

High-level waste issues and resolutions document  

SciTech Connect

The High-Level Waste (HLW) Issues and Resolutions Document recognizes US Department of Energy (DOE) complex-wide HLW issues and offers potential corrective actions for resolving these issues. Westinghouse Management and Operations (M&O) Contractors are effectively managing HLW for the Department of Energy at four sites: Idaho National Engineering Laboratory (INEL), Savannah River Site (SRS), West Valley Demonstration Project (WVDP), and Hanford Reservation. Each site is at varying stages of processing HLW into a more manageable form. This HLW Issues and Resolutions Document identifies five primary issues that must be resolved in order to reach the long-term objective of HLW repository disposal. As the current M&O contractor at DOE`s most difficult waste problem sites, Westinghouse recognizes that they have the responsibility to help solve some of the complexes` HLW problems in a cost effective manner by encouraging the M&Os to work together by sharing expertise, eliminating duplicate efforts, and sharing best practices. Pending an action plan, Westinghouse M&Os will take the initiative on those corrective actions identified as the responsibility of an M&O. This document captures issues important to the management of HLW. The proposed resolutions contained within this document set the framework for the M&Os and DOE work cooperatively to develop an action plan to solve some of the major complex-wide problems. Dialogue will continue between the M&Os, DOE, and other regulatory agencies to work jointly toward the goal of storing, treating, and immobilizing HLW for disposal in an environmentally sound, safe, and cost effective manner.

Not Available

1994-05-01

398

High-Level Waste Systems Plan. Revision 7  

SciTech Connect

This revision of the High-Level Waste (HLW) System Plan aligns SRS HLW program planning with the DOE Savannah River (DOE-SR) Ten Year Plan (QC-96-0005, Draft 8/6), which was issued in July 1996. The objective of the Ten Year Plan is to complete cleanup at most nuclear sites within the next ten years. The two key principles of the Ten Year Plan are to accelerate the reduction of the most urgent risks to human health and the environment and to reduce mortgage costs. Accordingly, this System Plan describes the HLW program that will remove HLW from all 24 old-style tanks, and close 20 of those tanks, by 2006 with vitrification of all HLW by 2018. To achieve these goals, the DWPF canister production rate is projected to climb to 300 canisters per year starting in FY06, and remain at that rate through the end of the program in FY18, (Compare that to past System Plans, in which DWPF production peaked at 200 canisters per year, and the program did not complete until 2026.) An additional $247M (FY98 dollars) must be made available as requested over the ten year planning period, including a one-time $10M to enhance Late Wash attainment. If appropriate resources are made available, facility attainment issues are resolved and regulatory support is sufficient, then completion of the HLW program in 2018 would achieve a $3.3 billion cost savings to DOE, versus the cost of completing the program in 2026. Facility status information is current as of October 31, 1996.

Brooke, J.N.; Gregory, M.V.; Paul, P.; Taylor, G.; Wise, F.E.; Davis, N.R.; Wells, M.N.

1996-10-01

399

Level 1 Tornado PRA for the High Flux Beam Reactor  

SciTech Connect

This report describes a risk analysis primarily directed at providing an estimate for the frequency of tornado induced damage to the core of the High Flux Beam Reactor (HFBR), and thus it constitutes a Level 1 Probabilistic Risk Assessment (PRA) covering tornado induced accident sequences. The basic methodology of the risk analysis was to develop a ``tornado specific`` plant logic model that integrates the internal random hardware failures with failures caused externally by the tornado strike and includes operator errors worsened by the tornado modified environment. The tornado hazard frequency, as well as earlier prepared structural and equipment fragility data, were used as input data to the model. To keep modeling/calculational complexity as simple as reasonable a ``bounding`` type, slightly conservative, approach was applied. By a thorough screening process a single dominant initiating event was selected as a representative initiator, defined as: ``Tornado Induced Loss of Offsite Power.`` The frequency of this initiator was determined to be 6.37E-5/year. The safety response of the HFBR facility resulted in a total Conditional Core Damage Probability of .621. Thus, the point estimate of the HFBR`s Tornado Induced Core Damage Frequency (CDF) was found to be: (CDF){sub Tornado} = 3.96E-5/year. This value represents only 7.8% of the internal CDF and thus is considered to be a small contribution to the overall facility risk expressed in terms of total Core Damage Frequency. In addition to providing the estimate of (CDF){sub Tornado}, the report documents, the relative importance of various tornado induced system, component, and operator failures that contribute most to (CDF){sub Tornado}.

Bozoki, G.E.; Conrad, C.S.

1994-05-01

400

Quench cooling under reduced gravity.  

PubMed

We report quench cooling experiments performed with liquid O(2) under different levels of gravity, simulated with magnetic gravity compensation. A copper disk is quenched from 300 to 90 K. It is found that the cooling time in microgravity is very long in comparison with any other gravity level. This phenomenon is explained by the insulating effect of the gas surrounding the disk. A weak gas pressurization (which results in subcooling of the liquid with respect to the saturation temperature) is shown to drastically improve the heat exchange, thus reducing the cooling time (about 20 times). The effect of subcooling on the heat transfer is analyzed at different gravity levels. It is shown that this type of experiment cannot be used for the analysis of the critical heat flux of the boiling crisis. The film boiling heat transfer and the minimum heat flux of boiling are analyzed as functions of gravity and subcooling. PMID:23944546

Chatain, D; Mariette, C; Nikolayev, V S; Beysens, D

2013-07-01

401

Quench cooling under reduced gravity  

NASA Astrophysics Data System (ADS)

We report quench cooling experiments performed with liquid O2 under different levels of gravity, simulated with magnetic gravity compensation. A copper disk is quenched from 300 to 90 K. It is found that the cooling time in microgravity is very long in comparison with any other gravity level. This phenomenon is explained by the insulating effect of the gas surrounding the disk. A weak gas pressurization (which results in subcooling of the liquid with respect to the saturation temperature) is shown to drastically improve the heat exchange, thus reducing the cooling time (about 20 times). The effect of subcooling on the heat transfer is analyzed at different gravity levels. It is shown that this type of experiment cannot be used for the analysis of the critical heat flux of the boiling crisis. The film boiling heat transfer and the minimum heat flux of boiling are analyzed as functions of gravity and subcooling.

Chatain, D.; Mariette, C.; Nikolayev, V. S.; Beysens, D.

2013-07-01

402

Symmetries in Evolving Space Time, and Their Connection to High Frequency Gravity Wave Production  

NASA Astrophysics Data System (ADS)

We claim that linking a shrinking prior universe via a wormhole solution for a pseudo time dependent Wheeler De Witt equation permits the formation of a short-term quintessence scalar field, which is tied to an initial configuration of the Einstein field equations allowing for high frequency gravitational waves (HFGW) at the onset of inflation. This is due to symmetries in space time which enable the creation of high frequency gravitational waves. The wormhole thermal bridge between prior to present universes is of less than Planck's time duration, yet has consequences up to our present cosmological era. It also leads to phase transition changes which form a template as to graviton production.

Beckwith, Andrew

2008-04-01

403

EMPLOYABILITY AND HIGH-LEVEL SKILLS EQUIPPING STUDENTS FOR SUCCESS  

E-print Network

The importance of higher-level skills to the knowledge-based economy 08 Aerospace engineering 10 Skills in an increasingly competitive world. This strategy focuses on the soft and hard skills required by a successful, Universities and Skills. #12;THE IMPORTANCE OF HIGHER LEVEL SKILLS TO THE KNOWLEDGE-BASED ECONOMY 05 Since its

Martin, Ralph R.

404

High testosterone levels predict low voice pitchamong men  

Microsoft Academic Search

We measured salivary testosterone levels and voice pitch, or fundamental frequency,among 61 male and 88 female college students. Higher levels of testosterone were significantlyassociated with lower pitched voices among males but not among females. The magnitude of theeffect was approximately the same as the magnitude of other relationships that have beenreported between testosterone and behavior. There are two plausible explanations

James M Dabbs; Alison Mallinger

1999-01-01

405

An Underlying Theory for Gravity  

E-print Network

A new direction to understand gravity has recently been explored by considering classical gravity to be a derived interaction from an underlying theory. This underlying theory would involve new degrees of freedom at a deeper level and it would be structurally different from classical gravitation. It may conceivably be a quantum theory or a non-quantum theory. The relation between this underlying theory and Einstein's gravity is similar to the connection between statistical mechanics and thermodynamics. We discuss the apparent lack of evidence of any quantum nature of gravity in this context.

Yuan K. Ha

2012-08-14

406

Three-dimensional inversion of regional P and S arrival times in the East Aleutians and sources of subduction zone gravity highs  

NASA Astrophysics Data System (ADS)

Free-air gravity highs over forearcs represent a large fraction of the power in the Earth's anomalous field, yet their origin remains uncertain. Seismic velocities, as indicators of density, are estimated here as a means to compare the relative importance of upper plate sources for the gravity high with sources in the downgoing plate. P and S arrival times for local earthquakes, recorded by a seismic network in the eastern Aleutians, are inverted for three-dimensional velocity structure between the volcanic arc and the downgoing plate. A three-dimensional ray tracing scheme is used to invert the 7974 P and 6764 S arrivals for seismic velocities and hypocenters of 635 events. One-dimensional inversions show that station P residuals are systematically 0.25-0.5 s positive at stations 0-30 km north of the Aleutian volcanic arc, indicating slow material, while residuals at stations 10-30 km south of the arc are 0.1-0.25 s negative. Both features are explained in three-dimensional inversions by velocity variations at depths less than 25-35 km. Tests using a one-dimensional or a two-dimensional slab starting model show that below 100 km depth, velocities are poorly determined and trade off almost completely with hypocenters for earthquakes at these depths. The locations of forearc velocity highs, in the crust of the upper plate, correspond to the location of the gravity high between the trench and volcanic arc. Free-air anomalies, calculated from the three-dimensional velocity inversion result, match observed gravity for a linear density-velocity relationship between 0.1 and 0.3 (Mg m-3)/(km s-1), when a 50-km-thick slab is included with a density of 0.055±0.005 Mg m-3. Values outside these ranges do not match the observed gravity. The slab alone contributes one third to one half of the total 75-150 mGal amplitude of the gravity high but predicts a high that is much broader than is observed. The inclusion of upper-plate velocity anomalies predicts the correct width of the anomaly, 100-150 km, where the anomaly is most positive. Because the forearc gravity high is continuous along the entire Aleutian arc and is found in most arcs globally, high upper-plate forearc velocities are suspected to be a common feature of the upper plate of most subduction zones. The forearc mass excesses appear to be sustained by upward regional flexure of the upper plate that partly balances the depression of the lower plate at the trench, thus elevating high-density and high-velocity material. Thus a part of the downward flexure of the subducting plate is regionally compensated by shallow positive mass anomalies in the upper plate, and the strength of the upper plate helps generate the forearc gravity highs.

Abers, Geoffrey A.

1994-03-01

407

Emplacement mechanism of gravity flows inferred from high resolution Lidar data: The 1944 Somma Vesuvius lava flow (Italy)  

NASA Astrophysics Data System (ADS)

A Digital Terrain Model derived from high resolution Lidar data allows the determination of the morphometric and physical parameters of a lava flow erupted from the Somma-Vesuvius volcano in 1944. The downstream variation of morphometric parameters including slope, aspect, relative relief, thickness, width, and cross sectional area is analyzed, and the changes in viscosity, velocity and flow rate are estimated. The aims of the analyses are to recognize different flow surfaces, to reconstruct the flow kinematics, and to obtain information on the mechanism of emplacement. The results indicate that the 1944 lava flow can be divided in three sectors: a near vent sector (NVS) characterized by a toe-like surface, an intermediate sector (IS) with an 'a'?type brittle surface, and a distal sector (DS) with a sheet-like ductile surface. Lateral leveés and channels do not occur in NVS, whereas they are well developed in IS. In DS, leveés increase with an increasing distance from the vent. Fold-like surfaces occur in NVS and DS, reflecting local shortening processes due to a decrease in the slope of the substratum and overflows from the main channel. IS and DS emplaced between March 18 and 21, 1944, whereas NVS emplaced on March 19 and partly covered IS. The morphometric and physical parameters indicate that IS moved in a 'tube'-like regime, whereas DS emplaced in a 'mobile crust' regime. The IS to DS transition is marked by an increase in velocity and the flow rate, and by a decrease in thickness, width, cross sectional area, and viscosity. This transition is due to an abrupt increase in the slope of the substratum. The estimated velocity values are in good agreement with the measurements during the 1944 eruption. The analysis used here may be extended to other lava flows. Some gravity flows (debris/mud flows, floods, and avalanches) have rheological properties and shapes similar to those of lavas, and the same process-form relationships may apply to these flows. The approach used here may be therefore useful for evaluating hazards from various gravity currents.

Ventura, Guido; Vilardo, Giuseppe

2008-03-01

408

Symmetries in Evolving Space-time and Their Connection to High-Frequency Gravity Wave Production  

NASA Astrophysics Data System (ADS)

Linking a shrinking prior universe via a wormhole solution for a pseudo time dependent Wheeler-De Witt equation permits the formation of a short-term quintessence scalar field. We claim that our model and the addition of the wormhole is tied to an initial configuration of the Einstein field equations, allowing for high-frequency gravitational waves (HFGW) at the onset of inflation. This is due to symmetries in space-time, which enable the creation of high-frequency gravitational waves. The duration of a wormhole thermal bridge between prior and present universes is less than Planck's time duration, but has consequences up to our present cosmological era. This also leads to phase transition changes that form a template for graviton production. The initial conditions so created also suggest optimal environmental conditions for advanced spacecraft propulsion systems.

Beckwith, A. W.

2008-01-01

409

High level waste interim storge architecture selection - decision report  

SciTech Connect

The U.S. Department of Energy (DOE) has embarked upon a course to acquire Hanford Site tank waste treatment and immobilization services using privatized facilities (RL 1996a). This plan contains a two-phased approach. Phase I is a proof-of-principle/connnercial demonstration- scale effort and Phase II is a fiill-scale production effort. In accordance with the planned approach, interim storage and disposal of various products from privatized facilities are to be DOE fumished. The high-level waste (BLW) interim storage options, or alternative architectures, were identified and evaluated to provide the framework from which to select the most viable method of Phase I BLW interim storage (Calmus 1996). This evaluation, hereafter referred to as the Alternative Architecture Evaluation, was performed to established performance and risk criteria (technical merit, cost, schedule, etc.). Based on evaluation results, preliminary architectures and path forward reconunendations were provided for consideration in the architecture decision- maldng process. The decision-making process used for selection of a Phase I solidified BLW interim storage architecture was conducted in accordance with an approved Decision Plan (see the attachment). This decision process was based on TSEP-07,Decision Management Procedure (WHC 1995). The established decision process entailed a Decision Board, consisting of Westinghouse Hanford Company (VY`HC) management staff, and included appointment of a VTHC Decision Maker. The Alternative Architecture Evaluation results and preliminary recommendations were presented to the Decision Board members for their consideration in the decision-making process. The Alternative Architecture Evaluation was prepared and issued before issuance of @C-IP- 123 1, Alternatives Generation and Analysis Procedure (WI-IC 1996a), but was deemed by the Board to fully meet the intent of WHC-IP-1231. The Decision Board members concurred with the bulk of the Alternative Architecture Evaluation results and recommendations. However, the Board required changes to some criteria definitions and weightings in establishing its own recommendation basis. This report documents information presented to the Decision Board, and the Decision Board`s recommendations and basis for these recommendations. The Board`s recommendations were fully adopted by the WHC Decision Maker, R. J. Murkowski, Manager, TWRS Storage and Disposal. The Decision Board`s recommendation is as follows. The Phase I BLW Interim storage concept architecture will use Vaults 2 and 3 of the Hanford Site Spent Nuclear Fuel Canister Storage Building, being located in the Hanford Site 200 East Area, and include features to faciliate addition of one or more vaults at a later date.

Calmus, R.B.

1996-09-27

410

High level production of tyrosinase in recombinant Escherichia coli  

PubMed Central

Background Tyrosinase is a bifunctional enzyme that catalyzes both the hydroxylation of monophenols to o-diphenols (monophenolase activity) and the subsequent oxidation of the diphenols to o-quinones (diphenolase activity). Due to the potential applications of tyrosinase in biotechnology, in particular in biocatalysis and for biosensors, it is desirable to develop a suitable low-cost process for efficient production of this enzyme. So far, the best production yield reported for tyrosinase was about 1?g?L-1, which was achieved by cultivating the filamentous fungus Trichoderma reesei for 6?days. Results In this work, tyrosinase from Verrucomicrobium spinosum was expressed in Escherichia coli and its production was studied in both batch and fed-batch cultivations. Effects of various key cultivation parameters on tyrosinase production were first examined in batch cultures to identify optimal conditions. It was found that a culture temperature of 32?°C and induction at the late growth stage were favorable, leading to a highest tyrosinase activity of 0.76 U mL-1. The fed-batch process was performed by using an exponential feeding strategy to achieve high cell density. With the fed-batch process, a final biomass concentration of 37?g?L-1 (based on optical density) and a tyrosinase activity of 13 U mL-1 were obtained in 28?hours, leading to a yield of active tyrosinase of about 3?g?L-1. The highest overall volumetric productivity of 103?mg of active tyrosinase per liter and hour (corresponding to 464?mU?L-1?h-1) was determined, which is approximately 15 times higher than that obtained in batch cultures. Conclusions We have successfully expressed and produced gram quantities per liter of active tyrosinase in recombinant E. coli by optimizing the expression conditions and fed-batch cultivation strategy. Exponential feed of substrate helped to prolong the exponential phase of growth, to reduce the fermentation time and thus the cost. A specific tyrosinase production rate of 103?mg?L?1?h?1 and a maximum volumetric activity of 464?mU?L?1?h-1 were achieved in this study. These levels have not been reported previously. PMID:23442796

2013-01-01

411

Gravity, Magnetism, and "Down": Non-Physics College Students' Conceptions of Gravity  

ERIC Educational Resources Information Center

This study investigates how students enrolled in entry-level geology, most of whom would graduate from college without university-level physics courses, thought about and applied the concept of gravity while solving problems concerning gravity. The repercussions of students' gravity concepts are then considered in the context of non-physics…

Asghar, Anila; Libarkin, Julie C.

2010-01-01

412

Combining Vision Verification with a High Level Robot Programming Language   

E-print Network

This thesis describes work on using vision verification within an object level language for describing robot assembly (RAPT). The motivation for this thesis is provided by two problems. The first is how to enhance a ...

Yin, Baolin

1984-01-01

413

46 CFR 182.530 - Bilge high level alarms.  

Code of Federal Regulations, 2013 CFR

...constructed of wood must, in addition to paragraph (a), provide bilge level alarms in all watertight compartments except small buoyancy chambers. (c) A visual indicator must be provided at the operating station to indicate when any automatic bilge pump...

2013-10-01

414

High-level salivary gland expression in transgenic mice  

Microsoft Academic Search

A 7.1 kb mini-gene construct containing cloned DNA from the murine parotid secretory protein (PSP) gene with 6.2 kb of the promoter, has previously been shown to direct specific mRNA expression to the salivary glands in transgenic mice. However, the level of transgene expression in the parotid gland was only a few percent of the endogenous level. This indicated that

Hans Jakob Larsen; Camilla Holm Brodersen; Jens Peter Hjorth

1994-01-01

415

High-Level Energy Estimation for ARM-Based SOCs  

Microsoft Academic Search

In recent years, power consumption has become a critical concern for many VLSI systems. Whereas several case studies demonstrate that technology-, layout-, and gate-level techniques offer power savings of a factor of two or less, architecture and system-level optimization can often result in orders of magnitude lower power consumption. Therefore, the energy-efficient design of portable, battery-powered systems demands an early

Dan Crisu; Sorin Dan Cotofana; Stamatis Vassiliadis; Petri Liuha

2004-01-01

416

High Antibody Levels to P. gingivalis in Cardiovascular Disease  

Microsoft Academic Search

Recent evidence suggests that strain variation in the serum IgG response to Porphyromonas gingivalis occurs in periodontal disease and cardiovascular disease (CVD). This study aimed to test the hypothesis that different P. gingivalis strains would elicit different levels of IgG, depending on a patient’s cardiovascular (CV) and periodontal health. For CVD patients, serum antibody levels increased significantly with increasing numbers

S. Bohnstedt; M. P. Cullinan; P. J. Ford; J. E. Palmer; S. J. Leishman; B. Westerman; R. I. Marshall; M. J. West; G. J. Seymour

2010-01-01

417

Low copper and high manganese levels in prion protein plaques  

USGS Publications Warehouse

Accumulation of aggregates rich in an abnormally folded form of the prion protein characterize the neurodegeneration caused by transmissible spongiform encephalopathies (TSEs). The molecular triggers of plaque formation and neurodegeneration remain unknown, but analyses of TSE-infected brain homogenates and preparations enriched for abnormal prion protein suggest that reduced levels of copper and increased levels of manganese are associated with disease. The objectives of this study were to: (1) assess copper and manganese levels in healthy and TSE-infected Syrian hamster brain homogenates; (2) determine if the distribution of these metals can be mapped in TSE-infected brain tissue using X-ray photoelectron emission microscopy (X-PEEM) with synchrotron radiation; and (3) use X-PEEM to assess the relative amounts of copper and manganese in prion plaques in situ. In agreement with studies of other TSEs and species, we found reduced brain levels of copper and increased levels of manganese associated with disease in our hamster model. We also found that the in situ levels of these metals in brainstem were sufficient to image by X-PEEM. Using immunolabeled prion plaques in directly adjacent tissue sections to identify regions to image by X-PEEM, we found a statistically significant relationship of copper-manganese dysregulation in prion plaques: copper was depleted whereas manganese was enriched. These data provide evidence for prion plaques altering local transition metal distribution in the TSE-infected central nervous system.

Johnson, Christopher J.; Gilbert, P.U.P.A.; Abrecth, Mike; Baldwin, Katherine L.; Russell, Robin E.; Pedersen, Joel A.; McKenzie, Debbie

2013-01-01

418

Evaluating Material Flammability in Microgravity and Martian Gravity Compared to the NASA Standard Normal Gravity Test  

NASA Technical Reports Server (NTRS)

Drop tower tests are conducted at Martian gravity to determine the flammability of three materials compared to previous tests in other normal gravity and reduced gravity environments. The comparison is made with consideration of a modified NASA standard test protocol. Material flammability limits in the different gravity and flow environments are tabulated to determine the factor of safety associated with normal gravity flammability screening. Previous testing at microgravity and Lunar gravity indicated that some materials burned to lower oxygen concentrations in low gravity than in normal gravity, although the low g extinction limit criteria are not the same as 1g due to time constraints in drop testing. Similarly, the data presented in this paper for Martian gravity suggest that there is a gravity level below Earth s at which materials burn more readily than on Earth. If proven for more materials, this may indicate the need to include a factor of safety on 1g flammability limits.

Oslon, Sandra. L.; Ferkul, Paul

2012-01-01

419

GRAIL Gravity Field Determination Using the Celestial Mechanics Approach  

NASA Astrophysics Data System (ADS)

To determine the gravity field of the Moon, the NASA mission GRAIL (Gravity Recovery and Interior Laboratory) inherits its concept from the GRACE (Gravity Recovery and Climate Experiment) mission. The use of inter-satellite Ka-band range-rate (KBRR) observations enables data acquisition even when the spacecraft are not tracked from the Earth. The data allows for a highly accurate estimation of the lunar gravity field on both sides of the Moon, which is crucial to improve the understanding of its internal structure and thermal evolution. In this presentation we discuss GRAIL-based lunar gravity fields generated with the Celestial Mechanics Approach. KBRR observations and position data (GNI1B products) are used to solve for the lunar gravity field parameters in a generalized orbit determination problem. Apart from normalized spherical harmonic coefficients up to degrees n ? 200, also arc- and satellite-specific parameters, like initial state vectors and pseudo-stochastic pulses, are set up as common parameters for all measurement types. The latter shall compensate for imperfect models of non-gravitational accelerations, e.g., caused by solar radiation pressure. In addition, especially for the data of the primary mission phase, it is essential to estimate time bias parameters for the KBRR observations. We compare our results from the nominal and from the extended mission phase with the official Level 2 gravity field models first released in October 2013. Our results demonstrate that the lunar gravity field can be recovered with a high quality by adapting the Celestial Mechanics Approach, even when using pre-GRAIL or pre-SELENE gravity field models as a priori fields and when replacing sophisticated models of non-gravitational accelerations by appropriately spaced and constrained pseudo-stochastic pulses.

Arnold, Daniel; Jäggi, Adrian; Bertone, Stefano; Beutler, Gerhard; Meyer, Ulrich; Mervart, Leos; Bock, Heike

2014-05-01

420

Effect of water immersion on cardiopulmonary physiology at high gravity (+Gz)  

NASA Technical Reports Server (NTRS)

The cardiopulmonary responses of eight male subject between 21-31 years exposed to 1, 2, and 3 Gz during immersion at 35 + or - 0.5 C to heart level and during control dry rides are studied. Ventilation, O2 consumption, the end-tidal pressure of CO2, heart frequency, cardiac output, functional residual capacity, and the arterial pressure of CO2 were measured. It is observed that as Gz increases ventilation, heart frequency, and O2 consumption increase, and the end-tidal and arterial pressures of CO2 decrease during dry rides, but are not altered during immersion. It is detected that the functional residual capacity is lower during immersion and decreases in both the dry and immersed state as Gz increases, and cardiac output decreases as Gz increases in dry rides. It is noted that changes produced by acceleration in a Gz direction are due to the effect on the systemic circulation rather than to the effect on the lungs.

Arieli, R.; Boutellier, U.; Farhi, L. E.

1986-01-01

421

Using APL to build science tutors for the high school level Manuel Alfonseca  

E-print Network

Using APL to build science tutors for the high school level Manuel Alfonseca Universidad Aut6noma several courses on the sciences for the high school level. An APL2 program has been written that accepts, currently applied successfully to Mathematics and Physics at the high school level. These courses

Alfonseca, Manuel

422

High Level Saliency Prediction for Smart Game Balancing George Alex Koulieris  

E-print Network

- der to investigate the impact of high level saliency on visual at- tention & gameplay. We conductedHigh Level Saliency Prediction for Smart Game Balancing George Alex Koulieris Technical University Cottbus Katerina Mania Technical University of Crete 1 High Level Saliency Predicting visual attention can

Mania, Katerina

423

HighLevel Perception, Representation, and Analogy: A Critique of Artificial Intelligence Methodology  

E-print Network

High­Level Perception, Representation, and Analogy: A Critique of Artificial Intelligence of Experimental and Theoretical Artificial Intelligence. #12; High­Level Perception, Representation, and Analogy: A Critique of Artificial Intelligence Methodology Abstract High­level perception---the process of making

Indiana University

424

40 CFR 1065.725 - High-level ethanol-gasoline blends.  

Code of Federal Regulations, 2014 CFR

... 2014-07-01 false High-level ethanol-gasoline blends. 1065.725 Section...Standards § 1065.725 High-level ethanol-gasoline blends. For testing vehicles capable of operating on a high-level ethanol-gasoline blend, create a test...

2014-07-01

425

The effect of overall level on sensitivity to interaural differences of time and level at high frequencies  

PubMed Central

For high-frequency complex stimuli, detection thresholds for envelope-based interaural time differences (ITDs) decrease with overall level. Substantial heterogeneity is, however, evident among the findings concerning the rate at which thresholds decline with level. This study investigated factors affecting the influence of overall level on threshold ITDs. Thresholds were measured as a function of overall level for 4-kHz-centered “targets” in three experiments focusing, respectively, on stimulus-type (sinusoidally amplitude-modulated or “transposed” tones), modulation frequency, and details concerning low-pass noise used to mask low-frequency distortion products. Results indicated that (1) log-ITD thresholds decreased linearly with overall level; (2) slopes relating log-ITD thresholds to level did not depend significantly on stimulus type; (3) lower modulation frequencies produced greater dependencies of thresholds on overall level than did higher modulation frequencies; (4) the effect of overall level on threshold-ITDs was independent of the interaural configuration and levels of the low-pass noise maskers tested; (5) synchronously gating the low-pass noise and target produced a greater dependency of thresholds on the overall level of the target than did continuous or temporally “fringed” presentation of the noise. A fourth experiment showed that threshold interaural level differences were somewhat less affected by changes in overall level than were threshold ITDs. PMID:23862824

Dietz, Mathias; Bernstein, Leslie R.; Trahiotis, Constantine; Ewert, Stephan D.; Hohmann, Volker

2013-01-01

426

The effect of overall level on sensitivity to interaural differences of time and level at high frequencies.  

PubMed

For high-frequency complex stimuli, detection thresholds for envelope-based interaural time differences (ITDs) decrease with overall level. Substantial heterogeneity is, however, evident among the findings concerning the rate at which thresholds decline with level. This study investigated factors affecting the influence of overall level on threshold ITDs. Thresholds were measured as a function of overall level for 4-kHz-centered "targets" in three experiments focusing, respectively, on stimulus-type (sinusoidally amplitude-modulated or "transposed" tones), modulation frequency, and details concerning low-pass noise used to mask low-frequency distortion products. Results indicated that (1) log-ITD thresholds decreased linearly with overall level; (2) slopes relating log-ITD thresholds to lev