Energy Technology Data Exchange (ETDEWEB)

The double-mode cepheid Y Car has been found to have a variable centre-of-mass velocity. Though the observations did not cover a cycle, an orbital period of about 400-600 days was estimated. Radial-velocity observations of this star have now been continued in order to derive the orbital elements. Observations were made with the photoelectric radial-velocity spectrophotometer at the coude focus of the 1.88-m reflector at Sutherland. The velocity system was standardized by frequent nightly observations of stars in the Mount Wilson catalogue with 'a'-quality radial velocities.

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The Sloan Digital Sky Survey (SDSS) started a new phase in August 2008, with new instrumentation and new surveys focused on Galactic structure and chemical evolution, measurements of the baryon oscillation feature in the clustering of galaxies and the quasar Ly{alpha} forest, and a radial velocity search for planets around {approx}8000 stars. This paper describes the first data release of SDSS-III (and the eighth counting from the beginning of the SDSS). The release includes 5-band imaging of roughly 5200 deg{sup 2} in the Southern Galactic Cap, bringing the total footprint of the SDSS imaging to 14,555 deg{sup 2}, or over a third of the Celestial Sphere. All the imaging data have been reprocessed with an improved sky-subtraction algorithm and a final, self-consistent recalibration and flat-field determination. This release also includes all data from the second phase of the Sloan Extension for Galactic ...

CERN Document Server

Dark matter particles form halos that contribute the major part of the mass of galaxy clusters. The formation of these cosmological structures have been investigated both observationally and in numerical simulations, which have confirmed the existence of a universal mass profile. However, the dynamic behaviour of dark matter in halos is not as well understood. We have used observations of 16 equilibrated galaxy clusters to show that the random velocities of dark matter particles are larger on average along the radial direction than along the tangential, and that the magnitude of this velocity anisotropy is radially varying. Our measurement implies that the collective behaviour of dark matter particles is fundamentally different from that of normal particles and the radial variation of the anisotropy velocity agrees with the predictions of numerical simulation.

International Nuclear Information System (INIS)

To aid in the study of lower hybrid current drive as a means of current profile control, the radial profile and velocity distribution of the fast current-carrying electrons and their time evolution must be known. As part of the recent effort to understand this fast electron transport, a diagnostic has been installed on PBX-M to measure the electron cyclotron emission from the fast electrons. An oblique horizontal view of upshifted cyclotron emission in the midplane can give radial as well as velocity space information about the fast electrons. Emission in X mode frequencies refracted by the right-hand cutoff is radially localized. The observed emission at a specific frequency comes only from the radial region r_t_u_r_n=#0. Emission measured by this new diagnostic has been found to be radially localized as predicted. It is also expected that ...

British Library Electronic Table of Contents (United Kingdom)

Abstract In this paper, the effect of several turbulence parameters during various flow conditions in Owens Valley, educed from coherent Doppler lidar data have been studied. Radial velocity structure functions are processed to estimate the turbulent kinetic energy (TKE) dissipation rate, integral length scale and velocity variance, assuming a theoretical model for isotropic wind fields. Corrections for turbulence measurements have been considered to address the complications due to inherent volumetric averaging of radial velocity over each range gate, noise of the lidar data, and the assumptions required to estimate effects of smaller scales of motion on turbulence quantities. Using data from the Terrain-induced Rotor Experiment (T-REX) in April-May 2006, vertical profiles of wind and tur...

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Detailed spray characteristics were obtained for a small-capacity, pressure-swirl atomizer using an Aerometrics phase-Doppler particle analyzer. Measurements included drop size and velocity distributions, liquid volume fluxes, and air velocities at four axial locations, 25,50,75, and 100 mm, with complete radial traverses at each location. Drop size results were compared with measurements from a Malvern laser-diffraction instrument, and integrated liquid volume fluxes were compared with measured flow rates to estimate measurement uncertainties. Drop sizes measured by the two independent techniques and area-weighted-averaged over the radial traverses at each of the four axial stations varied on average by less than 4 percent. Integrated volume flux measurements by the phase-Doppler instrument at four axial stations differed from the nozzle flow rate by at most 19 percent, with some of the difference due ...

CERN Document Server

The stellar disc kinematics in a sample of fifteen intermediate- to late-type edge-on spiral galaxies are studied using a dynamical modeling technique. The sample covers a substantial range in maximum rotation velocity and deprojected face-on surface brightness and contains seven spirals with either a boxy- or peanut-shaped bulge. Dynamical models of the stellar discs are constructed using the disc structure from $I$-band surface photometry and rotation curves observed in the gas. The differences in the line-of-sight stellar kinematics between the models and absorption line spectroscopy are minimized using a least-squares approach. The modeling constrains the disc surface density and stellar radial velocity dispersion at a fiducial radius through the free parameter $\\sqrt{M/L}$ $(\\sigma_{\\rm z}/\\sigma_{\\rm R})^{-1}$, where $\\sigma_{\\rm z}/\\sigma_{\\rm R}$ is the ratio of vertical and radial ...

Scientific Electronic Library Online (English)

Abstract in english In this work the air flow in a furnace was computationally investigated. The furnace, for which experimental test data are available, is composed of a movable block burner connected to a cylindrical combustion chamber by a conical quarl. The apertures between the movable and the fixed blocks of the burner determine the ratio of the tangential to the radial air streams supplied to the furnace. Three different positions of the movable blocks were studied at this time. A thr (more) ee-dimensional investigation was performed by means of the finite volume method. The numerical grid was developed by the multiblock technique. The turbulence phenomenon was addressed by the RNG k-epsilon model. Profiles of the axial, tangential and radial velocities in the combustion chamber were outlined. The map of the predicted axial velocity in the combustion chamber was compared with a map of the ...

CERN Document Server

We present moderate resolution spectroscopy of extraplanar diffuse ionized gas (EDIG) emission in the edge-on spiral galaxy NGC 4302. The spectra were obtained with the SparsePak integral field unit (IFU) at the WIYN Observatory. The spectra are used to construct position-velocity (PV) diagrams at several ranges of heights above the midplane. Azimuthal velocities are directly extracted from the PV diagrams using the envelope tracing method, and indicate an extremely steep dropoff in rotational velocity with increasing height, with magnitude ~30 km/s/kpc. We find evidence for a radial variation in the velocity gradient on the receding side. We have also performed artificial observations of galaxy models in an attempt to match the PV diagrams. The results of a statistical analysis also favor a gradient of ~30 km/s/kpc. We compare these results with an entirely ballistic model of ...

Science.gov (United States)

The macroscopic rotation of plasma in a toroidal containment device is an important feature of the equilibrium. Toroidal and polidal rotation in the high-beta tokamak Torus II is measured experimentally by examining the Doppler shift of the 4685.75 A He II line emitted from the plasma. The toroidal flow at an average velocity of 1.6 x 10/sup 6/ cm/sec, a small fraction of the ion thermal speed, moves in the same direction as the toroidal-plasma current. The poloidal flow follows the ion diamagnetic current direction, also at an average speed of 1.6 x 10/sup 6/ cm/sec. In view of certain ordering parameters, the toroidal flow is compared with predictions from neoclassical theory in the collisional, Pfirsch-Schluter regime. The poloidal motion, however, results from an E x B drift in a positive radial electric field, approaching a stable ambipolar state. This radial electric field is determined from theory by using the ...

Energy Technology Data Exchange (ETDEWEB)

Improved separation of heavier material from a dispersoid of gas and heavier material entrained therein is taught by the method of this invention which advantageously uses apparatus embodied in an inertial separator having rotary partition means comprising wall members dividing a housing into a plurality of axially-extending through passages arranged in parallel. Simultaneously with the helical transit of a moving stream of the dispersoid through the parallel arrangement of axially-extending through passages at a constant angular velocity, the heavier material is driven radially to the collecting surfaces of the rotational wall members where it is collected while the wall members are rotating at the same angular velocity as the moving stream. The plurality of wall members not only provides an increased area of collecting surfaces but the positioning of each of the wall members according to the teaching of this invention ...

International Nuclear Information System (INIS)

The combined magnetic braking-ambipolar diffusion problem in weakly ionized, rigidly rotating disks is studied. An analytical solution is presented for a disk whose angular velocity and magnetic yield vectors are aligned with the symmetry axis, illustrating the effects of the relative azimuthal drift of neutrals and ions. The effects of radial drift are added, commenting on the ratio of the characteristic ambipolar diffusion and magnetic braking time scales in high-mass and low-mass disks. A numerical calculation is used to show the combined action of these two processes. 31 references.

Science.gov (United States)

Radial Halbach magnetic bearings have been investigated as part of an effort to develop increasingly

Energy Technology Data Exchange (ETDEWEB)

This thesis develops methods for recording and analysis of seismo-acoustic interface waves for determination of shear wave velocity as a function of depth and includes this in standard refraction seismic surveying. It investigates different techniques for estimation of dispersion characteristics of the interface waves and demonstrates that multi sensor spectral estimation techniques improve the dispersion estimates. The dispersion estimate of the fundamental interface wave mode is used as input to an object function for a model based linearized inversion. The inversion scheme provides an estimate of the shear wave velocity as a function of depth. Three field surveys were performed. Data were acquired with a standard bottom deployed refraction seismic hydrophone array containing 24 or 48 receivers, with a receiver spacing of 2.5 m. Explosive charges were used as sources. The recording time was increased ...

CERN Document Server

In a recent survey of the stellar populations of LINERS and LINER/HII Transition Objects (TOs) we identified a numerous class of nuclei which stand out because of their conspicuous 10^8-9 yr populations. These objects were called ``Young-TOs'', since they all have TO-like emission line ratios. In this paper we investigate the radial variations of spectral properties in Low Luminosity AGN. Our analysis is based on high S/N, 3500-5500 A, long-slit spectra for 47 galaxies. The data probe distances of typically up to 850 pc from the nucleus with a resolution of ~ 100 pc and S/N ~ 30. Stellar population gradients are mapped by the radial profiles of absorption line equivalent widths and colours along the slit. These variations are further analyzed by means of a decomposition of each spectrum in terms of template galaxies representative of very young (<= 10^7 yr), intermediate age (10^8-9 yr) and old (10^10 yr) populations. ...

International Nuclear Information System (INIS)

In this article, the ability of artificial neural networks in prediction of separation in steady two dimensional boundary layer flows is studied. Data for network training is extracted from numerical solution of an ODE obtained from Von Karman integral equation with approximate one parameter Pohlhousen velocity profile. As an appropriate neural network, a two layer radial basis generalized regression artificial neural network is used. The results shows good agreements between the overall behavior of the flow fields predicted by the artificial neural network and the actual flow fields for some cases. The method easily can be extended to unsteady separation and turbulent as well as compressible boundary layer flows. (author)

CERN Document Server

We compare the metallicities of stars with radial velocity planets to the metallicity of a sample of field dwarfs. We confirm recent work indicating that the stars-with-planet sample as a whole is iron rich. However, the lowest mass stars tend to be iron poor, with several having [Fe/H]0.48) that contributes to but does not explain the mass-metallicity trend in the stars-with-planets sample. We use Monte Carlo models to show that adding an average of 6.5 Earth masses of iron to each star can explain both the mass-metallicity and the age-metallicity relations of the stars-with-planets sample. However, for at least one star, HD 38529, there is good evidence that the bulk metallicity is high. We conclude that the observed metallicities and metallicity trends are the result of the interaction of three effects; accretion of about 6 Earth masses of iron rich material, selection effects, and in some cases, high intrinsic metallicity.

Energy Technology Data Exchange (ETDEWEB)

The two-phase flow regime transition in a large diameter (I.D.=200mm) vertical pipe was experimentally investigated using a dual-sensor optical probe. The flow transitions from bubbly to chum without an intermediate slug flow regime as the air flow rate is increased. The transition boundaries developed for bubbly to slug flow in small diameter pipes are compared to the bubbly to chum flow transition of the present experiment. The bubbly to chum transition occurs at a void fraction of about 0.15 compared to 0.25 for bubbly to slug transition in small diameter pipes. The radial distribution of bubble diameter, bubble frequency, bubble velocity and local void fraction were obtained using a dual-sensor optical probe at different flow conditions. The Probability Density Function (PDF) and Cumulative Distribution Function (CDF) of the bubble velocity and size are used to study the flow regime transition in the large diameter ...

International Nuclear Information System (INIS)

During the 2007 Niigataken Chuetsu-oki earthquake, strong ground motion with the peak acceleration of 680 cm/s/s which was larger than that of the empirical prediction was recorded at the base mat of the No.1 reactor building of Kashiwazaki-Kariwa Nuclear Power Station (NPS). Furthermore, in the Kashiwazaki-Kariwa NPS, over twice difference of 680 vs. 322 cm/s/s of peak acceleration between the No.1 and the No.6 reactor buildings was observed on the base mat. From the results of recent research, it is suggested that the deep sedimentary layers can be one of the important factors to elucidate these phenomena. In this study, at first, the applicability of microtremor array measurements for estimation of deep S-wave velocity structure (#approx#Vs=3 km/s layer) are discussed. Vertical microtremors were observed in three arrays at the Kashiwazaki-Kariwa NPS with the maximum station spacings of 3.04 km, 1.49 km and 0.75 km, respectively. The Rayleigh wave phase ...

Science.gov (United States)

In our previous paper (Lanzafame et al. 2000, PASJ 52, 515) we showed, through 2D SPH simulations, that the stellar mass ratio, M 2 / M 1, of a close binary system (that determines the position and then the initial specific angular momentum at L 1) plays a fundamental role in the formation and development of spiral structures and shock fronts in the radial flow of accretion discs. In that work only a quasi-sonic value of the injection velocity at L 1 was considered. In the present work we also carried out 2D SPH simulations with the aim to investigate the development of such structures, while keeping constant the mass of the compact primary (M 1 = 1 M odot) and the separation between the two components, and assuming as an initial condition of two different supersonic injection velocities at L 1, characterizing two sets of simulations. For each set we considered four values of the secondary to primary mass ratio, M 2 / M 1. ...

International Nuclear Information System (INIS)

This study deals with testing the capacity of the code PARET to simulate natural circulation phenomena under different boundary conditions in addition to assessment of some new options related to simulation of control rod movement and the reactivity effect of thermal expansion fuel elements. the experiments of the simple thermal hydraulic loop of Missouri University about natural circulation phenomena in narrow parallel channel were used to validate the code. The results indicate good agreements regarding the evolution of coolant velocity and clad temperature. In particular the heat transfer coefficient of natural convection has been calculated in good agreement with the experiment. On the other hand, the core of MNSR reactor has been modelled to stimulate the reactor dynamic behaviour under natural circulation condition for different initial power level. The observed oscillations during the initial phase vanish gradually with passing time. In this context three ...

CERN Document Server

Applied survey methods

International Nuclear Information System (INIS)

Stellar rotation and velocity-dispersion measurements are presented for the bulge components of the SBO galaxies NGC 1023, 2859, 2950, 4340, 4371, and 7743. The kinematics of nine SB bulges with data available are compared with bulges of unbarred galaxies studied by Kormendy and Illingworth. All of the SB bulges are found to rotate at least as rapidly as oblate-spheroid dynamical models which are flattened by rotation. This result confirms the conclusion of Kormendy and Illingworth that bulges rotate very rapidly. Six SB bulges found by Kormendy and Koo to be triaxial rotate even more rapidly than the oblate models. In this respect, they resemble published n-body models of bars. That is, triaxial bulges are dynamically like bars and unlike elliptical galaxies, which are also believed to be triaxial, but which rotate slowly. Measured velocity anisotropies are found to be consistent with these conclusions. Two ordinary bulges whose rotation is ...

International Nuclear Information System (INIS)

A theoretical model is presented to describe the electromagnetic, heat transfer and fluid flow phenomena within a magnetron plasma torch and in the resultant plume, by using a commercial computational fluid dynamics (CFD) code FLUENT. Specific calculations are presented for a pure argon system (i.e., an argon plasma discharging into an argon environment), operated in a turbulent mode. An important finding of this work is that the external axial magnetic field (AMF) may have a significant effect on the behavior of arc plasma and thus affects the resulting plume. The AMF impels the plasma to retract axially and expand radially. As a result, the plasma intensity distribution on the cross section of torch seems to be more uniform. Numerical results also show that with AMF, the highest plasma temperature decreases and the anode arc root moves upstream significantly, while the current density distribution at the anode is more concentrated with a higher peak value. In ...

International Nuclear Information System (INIS)

A new foilless diode with a non-magnetically immersed cathode was recently designed and built for the Sandia Recirculating Linear Accelerator (RLA). Because there is also no radial component of electric field at the cathode, the electron beam starts almost parallel and is matched to a solenoidal transport system with minimum increase in divergence and radius. The electrode emission surface is specified by an area covered with felt which undergoes explosive electron emission at low electrical field stresses (60 kV/cm). The 1.7 MV, 4.8-kA produced beam is transported 1.5 meters to the injection region of the racetrack via a system of solenoids and focusing coils. The maximum transverse velocity component at injection point (1.5 m downstream from the cathode surface) is #beta# perpendicular = 0.03 and the radius r = 2.8 cm which give a quite small beam emittance #epsilon# = 0.08 rad-cm. Three- dimensional numerical simulations suggest that ...

International Nuclear Information System (INIS)

New physical objects, ispalators based on free soap films, exhibit persistent flows of the soap solution in open and closed volumes in air with additions of gases of the C_8F_1_8 type (p = 20 Torr) at temperature drops on the films of the order of tenths and hundredths of kelvin. The flows move continuously at a velocity of 5 - 20 cm s"-"1. It is found that the parts of an inclined ispalator film show anomalous behaviour upon heating: their weight increases and they move downward over the film, whereas the unheated parts of the film move upward. Continuous radial vortex flows accompanied by the formation and washing of the regions of a thin black film are observed on circular films in closed volumes upon their uniform external cooling by evaporating water for 5 - 10 hours. The rapid flows make film ispalators the efficient heat carriers, which operate at small temperature drops (tenths and hundredths of kelvin) and surpass copper in the amount ...

CERN Document Server

Correlations are studied between the power density of Alfv\\'en-cyclotron waves (having frequencies between 0.02 and 2 Hz) and the ratio of the perpendicular and parallel temperature of the protons. The wave power spectrum is evaluated from high-resolution 3D magnetic field vector components, and the ion temperatures are derived from the velocity distribution functions as measured in fast solar wind during the Helios-2 primary mission at radial distances from the Sun between 0.3 AU and 0.9 AU. From our statistical analysis, we obtain a striking correlation between the increases in the proton temperature ratio and enhancements in the wave power spectrum. Near the Sun the transverse part of the wave power is often found to be by more than an order of magnitude higher than its longitudinal counterpart. Also the measured ion temperature anisotropy appears to be limited by the theoretical threshold value for the ion-cyclotron instability. This ...

CERN Document Server

Most of the presently identified exoplanets have masses similar to that of Jupiter and therefore are assumed to be gaseous objects. With the ever-increasing interest in discovering lower-mass planets, several of the so-called super-Earths (i.e., with masses in the interval 1 M_earth < M < 10 M_earth), which are predicted to be rocky, have already been found. Here we report the possible discovery of a planet around the M-type star GJ 436 with a minimum mass of 4.8+/-0.6 M_earth and a true mass of ~5 M_earth, which makes it the least massive planet around a main-sequence star found to date. In contrast with other discoveries, the planet is identified from its perturbations on an inner Neptune-mass transiting planet (GJ 436b), by pumping eccentricity and producing secular variations in the orbital inclination. Analysis of published radial velocity measurements indeed reveals a significant signal corresponding to an orbital period that is ...

CERN Document Server

Observations of redshift-space distortions in spectroscopic galaxy surveys offer an attractive method for measuring the build-up of cosmological structure, which depends both on the expansion rate of the Universe and our theory of gravity. Galaxies occupy dark matter halos, whose redshift space clustering has a complex dependence on bias that cannot be inferred from the behavior of matter. We identify two distinct corrections on quasilinear scales (~ 30-80 Mpc/h): the non-linear mapping between real and redshift space positions, and the non-linear suppression of power in the velocity divergence field. We model the first non-perturbatively using the scale-dependent Gaussian streaming model, which we show is accurate at the 10 (s>25) Mpc/h for the monopole (quadrupole) halo correlation functions. We use perturbation theory to predict the real space pairwise halo velocity statistics. Our fully analytic model is accurate at ...

Energy Technology Data Exchange (ETDEWEB)

Lie group methods provide a valuable tool for examininginvariance and non-uniqueness associated with geophysical inverseproblems. The techniques are particularly well suited for the study ofnon-linear inverse problems. Using the infinitesimal generators of thegroup it is possible to move within the null space in an iterativefashion. The key computational step in determining the symmetry groupsassociated with an inverse problem is the singular value decomposition(SVD) of a sparse matrix. I apply the methodology to the eikonal equationand examine the possible solutions associated with a crosswelltomographic experiment. Results from a synthetic test indicate that it ispossible to vary the velocity model significantly and still fit thereference arrival times. the approach is also applied to data fromcorosswell surveys conducted before and after a CO2 injection at the LostHills field in California. The results highlight the fact that a ...

Energy Technology Data Exchange (ETDEWEB)

A three-component seismic line acquired over the Zamora gas field, northern Sacramento Valley, California, displays conventional (P-P) and converted-wave (P-SV) seismic anomalies. Well log and seismic modeling results indicate that bright-spot reflection strengths are related to variations in fluid saturation and lithology. The converted-wave reflection strengths and interval velocities provide valuable information that compliments more conventional strategies such as amplitude with offset and polarity analysis. This integrated strategy can improve risk evaluation and well site selection in areas where rapid changes in reservoir quality impact resource evaluation.

International Nuclear Information System (INIS)

We have observed the CH_3OH J = 2-1, SiO J = 2-1, C"3"4S J = 2-1, H"1"3CO"+ J = 1-0, HN"1"3C J = 1-0, CCH N = 1-0, OCS J = 8-7, and SO J_N = 2_2-1_1 lines toward 20 massive clumps, including Midcourse Space Experiment (MSX) 8 #mu#m dark sources (infrared dark clouds) and MSX 8 #mu#m sources, by using the Nobeyama Radio Observatory 45 m telescope. We have found that the velocity widths of the CH_3OH and C"3"4S lines are broader than those of the H"1"3CO"+ line in the MSX dark sources. On the other hand, they are comparable to the velocity width of the H"1"3CO"+ line in the MSX sources. In addition, the [SiO]/[H"1"3CO"+] abundance ratio is found to be enhanced in the MSX dark sources in comparison with the MSX sources. These results suggest that shocks caused by interaction between an outflow and an ambient dense gas would have substantial impact on the chemical composition of the MSX dark sources. The velocity widths of the ...

Energy Technology Data Exchange (ETDEWEB)

Atomization of liquid fuel in aircraft engines requires application of airblast atomizers, where the kerosene is supplied into the shear layer between two swirling airstreams. The transfer of this functional principle towards gaseous fuel, as illustrated in Fig. 1, yielded a strong influence of the swirl arrangement of the airflows on flame stability and homogeneity of the fuel/air-mixture. Compared to the co-swirl configuration the flow field of the counter-swirl arrangement exhibits a marked increase of the mass flow recirculated in the internal recirculation zone and a reduction of its length in axial direction. This is attributed to the faster decay of tangential velocity maxima in case of counter-rotating airflows. This generates a stronger positive axial pressure gradient dp/dx, thus enhancing the internal recirculation zone. Analysis of local turbulence quantities yields a restriction of turbulent exchange to smaller radial sections and ...

UK PubMed Central (United Kingdom)

A single radial hemolysis test was developed for quantitation of specific antibody to non-hemagglutinating viruses. With the human coronaviruses as models, this test utilizes the binding properties...Full Text Available

British Library Electronic Table of Contents (United Kingdom)

The influence of geometry and operating conditions of the centrifugal compressor stage on the radial gas force is determined on the basis of the theoretical method and calculation program using experimental boundary conditions.

Science.gov (United States)

Aliens in Antarctica - General Visitor Survey and Visitor Clothing Survey data ... Description: EOI page of the Aliens in Antarctica project ...

Science.gov (United States)

... the vertical beam measures the movement of the ... be measured because the particle velocity in ... During precipitation, if the hydrometeor fall velocity is ...

Energy Technology Data Exchange (ETDEWEB)

A radial-flow type internally oil-cooled oil-filled cable has been developed. This system is characterized in that the oil flows radially through the paper insulation. The thermal resistance of the insulation is equivalently decreased by the radial-flow. The decreased thermal resistance as well as the cooling effect of the oil flow in the central oil duct and the outer oil duct under an aluminum sheath increase the current capacity. A calculation method of cooling characteristics is introduced. The stability of the cable and accessories was confirmed through initial electrical tests and a long-term field test.

Energy Technology Data Exchange (ETDEWEB)

An assessment of the cooling requirements for fusion reactor components, such as the first wall and limiter/divertor, was carried out using pressurized water as the coolant. In order to establish the coolant operating conditions, a survey of the literature on departure from nucleate boiling, critical heat flux, asymmetrical heating and heat transfer augmentation techniques was carried out. The experimental data and the empirical correlations indicate that thermal protection for the fusion reactor components based on current design concepts can be provided with an adequate margin of safety without resorting to either high coolant velocities, excessive coolant pressures, or heat transfer augmentation techniques. If, however, the future designs require heat transfer enhancement techniques, experimental verification would be necessary since no data on heat transfer augmentation techniques exist for complex geometries, especially under ...

Energy Technology Data Exchange (ETDEWEB)

An assessment of the cooling requirements for fusion reactor components, such as the first wall and limiter/divertor, was carried out using pressurized water as the coolant. In order to establish the coolant operating conditions, a survey of the literature on departure from nucleate boiling, critical heat flux, asymmetrical heating and heat transfer augmentation techniques was carried out. The experimental data and the empirical correlations indicate that thermal protection for the fusion reactor components based on conventional design concepts can be provided with an adequate margin of safety without resorting to either high coolant velocities, excessive coolant pressures, or heat transfer augmentation techniques. If, however, the future designs require unconventional shapes or heat transfer enhancement techniques, experimental verification would be necessary since no data on heat transfer augmentation techniques exist for complex geometries, ...

CERN Document Server

We study the stellar and dust properties of a well-defined sample of local elliptical galaxies to investigate the relationship between host galaxy properties and nuclear activity. We select a complete sample of 45 ellipticals from the Palomar spectroscopic survey of nearby galaxies, which includes 20 low-luminosity active galactic nuclei classified as LINERs and 25 inactive galaxies. Using a stellar population synthesis method, we compare the derived stellar population properties of the LINER versus the inactive subsamples. We also study the dust and stellar surface brightness distributions of the central regions of these galaxies using high-resolution images obtained with the {\\it Hubble Space Telescope}. Relative to the inactive subsample, ellipticals hosting LINERs share similar total optical and near-infrared luminosity, central stellar velocity dispersions, and nuclear stellar populations as judged from their luminosity-weighted ages and ...

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Anisotropy has been investigated using S-wave as a technique for detecting fractures. In this study, fundamental experiments were carried out with slightly changing the measuring conditions at a place where anisotropy was expected. This paper describes the fundamental data acquisition of anisotropy analysis using S-wave, and a part of the results. The experiments were conducted on the agricultural road in Yamadera district, Matsuyama-machi, Yamagata Prefecture. Two flat unpaved roads meeting at right angles were used as traverse lines. In this place, several reflection surfaces were certainly detected by P-wave, and anisotropy of S-wave was confirmed from the velocity of refracted wave of S-wave. Data were processed for individual traverse lines meeting at right angles. Firstly, signal sweeping, correlation, and vertical superposition were made. Six kinds of data were prepared, i.e., three-component receiving records of data at 0{degree} of generating direction and ...

Energy Technology Data Exchange (ETDEWEB)

The radial distribution function (RDF) derived from wide angle X-ray diffraction patterns gives additional information about the spatial distribution of atoms. Their radial distances and relative average coordination numbers can be calculated using appropriate mathematical procedures. 7 refs.

Energy Technology Data Exchange (ETDEWEB)

The impingement of a fluid jet onto a surface has broad applications across many industries. Within the UK nuclear industry, during the final stages of fuel reprocessing, impinging fluid jets are utilised to mobilise settled sludge material within storage tanks and ponds in preparation for transfer and ultimate immobilisation through vitrification. Despite the extensive applications of impinging jets within the nuclear and other industries, the study of two-phase, solid loaded, impinging jets is limited, and generally restricted to computational modelling. Surprisingly, very little fundamental understanding of the turbulence structure within such fluid flows through experimental investigation is found within the literature. The physical modelling of impinging jet systems could successfully serve to aid computer model validation, determine operating requirements, evaluate plant throughput requirements, optimise process operations and support design. Within this project a method is ...

Energy Technology Data Exchange (ETDEWEB)

An axisymmetric plasma screw pinch is an axisymmetric column of ionized gaseous plasma radially confined by forces from axial and azimuthal currents driven in the plasma and its surroundings. This dissertation is a contribution to detailed, high resolution computer simulation of dynamic plasma screw pinches in 2-d {ital rz}-coordinates. The simulation algorithm combines electron fluid and particle-in-cell (PIC) ion models to represent the plasma in a hybrid fashion. The plasma is assumed to be quasineutral; along with the Darwin approximation to the Maxwell equations, this implies application of Ampere`s law without displacement current. Electron inertia is assumed negligible so that advective terms in the electron momentum equation are ignored. Electrons and ions have separate scalar temperatures, and a scalar plasma electrical resistivity is assumed. Altemating-direction-implicit (ADI) methods are used to advance the electron fluid drift ...

CERN Document Server

An accident of misidentification has brought to light the interesting system HD 191588, a new RS CVn-type spectroscopic binary. A radial-velocity study of the primary star, the only seen component, carried out at the Observatoire de Haute-Provence with the Coravel instrument and subsequently at the Cambridge Observatories with a similar one, reveals two orbital motions: a short-period orbit (60 days) and a long-period one (about 4.5 years), so this star is a triple system. The following orbital elements are obtained: (1) for the long-period orbit P = 1667+/-17 days, T = 50901 +/-67 MJD, Gamma = +2.09 +/-0.07 km/s, K = 2.51 +/-0.13 km/s, e = 0.18 +/-0.04, omega = 228deg +/- 14 deg, a1 sin i = 56.7 +/- 3.0 Gm, f(m) = 0.0026 +/-0.0004 M_sun, and (2) for the short-period orbit P = 60.0269 +/-0.0016 days, T = 50482.6 +/-3.3 MJD, gamma is var., K = 24.03 +/- 0.09 km/s, e = 0.012 +/-0.004, omega = 233 deg +/-19deg, a1 sin i = 19.83 +/-0.07 Gm, f(m) = 0.0865 +/-0.0009 ...

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heterogeneity bias Static models: Other models:

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CERN Document Server

We performed a spectroscopic galaxy survey, complete to $m_{F814W}\\leq20.3$ ($L_B>0.15L_B^{\\star}$ at z=0.3), within 100x100'' of the quasar Q1127-145 ($z_{em}=1.18$). The VLT/UVES quasar spectrum contains three $z_{abs}<0.33$ MgII absorption systems. We obtained eight new galaxy redshifts, adding to the four previously known, and galaxy star formation rates (SFRs) and metallicities were computed where possible. A strong MgII system [$W_r(2796)=1.8$A], which is a known damped Ly$\\alpha$ absorber (DLA), had three previously identified galaxies; we found two additional galaxies associated with this system. These five galaxies form a group with diverse properties, such as a luminosity range of $0.04\\leq L_B\\leq0.63 L_B^{\\star}$, an impact parameter range of $17\\leq D \\leq 241$ kpc and velocity dispersion of $\\sigma$=115 km/s. The DLA group galaxy redshifts span beyond the 350 km/s velocity spread of the metallic ...

International Nuclear Information System (INIS)

GRR-1 is a 5MW open pool type research reactor with MTR-type fuel elements cooled and moderated by light water with beryllium reflectors at the two opposing sides of the core. A graphite thermal neutron column is adjusted to one side of the core. Six radial horizontal beam tubes are available, of which three contain in-pile collimators for neutron scattering instruments. The reactor is currently out of operation for inspection and refurbishment purposes. The core has been dismantled and the fuel elements are stored in the used fuel storage tank. The GRR-1 inspection and refurbishment plan involves inspection and eventually replacement of the reactor's primary cooling circuit. The health physics procedures to be implemented during inspection of the main water outlet are divided in three stages: a) pool dose rate survey from pool top, b) pool drainage by decreasing water level in steps and c) inspection of the water main outlet. urpose of the ...

Energy Technology Data Exchange (ETDEWEB)

Restructuring was carried out on a sedimentary basin structure model of the Osaka plain including Osaka Bay by using newly obtained underground structural data. After the Hygoken-nanbu Earthquake of 1995, a large number of underground structure investigations have been performed in Osaka Bay and urban areas of Kobe and Osaka. However, very few surveys have been done in areas peripheral to Osaka Prefecture, such as the Ikoma area. Therefore, an attempt has been made to increase the number of measuring points to acquire underground structural data of these areas. Estimation of basic rock depths has utilized the dominant cycles in H/V spectra obtained from micro vibration survey, and good correlation of the base rock depths derived by a refraction exploration and a deep-bed boring investigation. With regard to bed division and P- and S- wave velocities in sedimentary beds in the Osaka sedimentary basin, an underground ...

UK PubMed Central (United Kingdom)

The torque-velocity relationship is known to be affected by ageing, decreasing its protective role in the prevention of falls. Interindividual variability in this torque-velocity relationship is partly...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

This report summarizes the information gathered by CONCAVE in a 1993 survey of waste generation and disposal by the oil refineries in Western Europe. The survey covered the types of waste produced, their quantities, disposal routes and costs of disposal. The results are compared with those from a 1986 survey, but because of the increased numbers of refineries reporting, comparison is difficult. The survey revealed wide variations in disposal costs depending on waste type and local circumstances.

Energy Technology Data Exchange (ETDEWEB)

Role of ballooning effect in toroidal plasmas on the transient transport problems is investigated. Due to the mode localization along the magnetic field line, a meso scale appears in a radial correlation length of fluctuating fields. This scale length introduces the interference of the gradient and flux in different radial locations. For the fluctuation which gives the gyro-Bohm-like diffusion in a stationary state, this long radial correlation of the fluctuating field causes a fast propagation of response against a rapid transient perturbation. Upper bound of transient thermal diffusivity is derived. (author)

Science.gov (United States)

... Figure 1.4. Low Velocity Impact 1-4 Page 25. Damage of composite sandwich panels caused by low velocity impact has been ...

Science.gov (United States)

Eckert, B., "Axial Kompressoren und Radial Kompressoren," Springer. Verlag, Berlin, 1953. 3. Lebot, Y., et al., "Theoretical and Experimental Determination ...

Energy Technology Data Exchange (ETDEWEB)

This paper introduces a novel three-phase power flow approach for unbalanced radial distribution systems. The proposed approach is developed based on the loop frame of reference, rather than the traditional bus frame of reference. On the basis of the loop frame of reference, a simple direct iterative method in impedance form is applied. Basic graph theory and injection current technique are also applied in the proposed approach. The clear theoretical foundation and the simple topology of the radial distribution network make the proposed method efficient and reliable. To demonstrate the better convergence performance and the efficiency of the proposed approach, four three-phase IEEE test feeders are used for comparisons. The test results show that the proposed method has robust convergence characteristics and high performance, especially for large-scale radial distribution systems. (author)

Energy Technology Data Exchange (ETDEWEB)

The present emphasis on inherent safety for LMR designs has resulted in a need to represent the various reactivity feedback mechanisms as accurately as possible. The dominant negative reactivity feedback has been found to result from radial expansion of the core for most postulated ATWS events. For this reason, a more detailed model for calculating the reactivity feedback from radial core expansion has been recently developed for use with the SASSYS/SAS4A Code System. The purpose of this summary is to present an extension to the model so that it is more suitable for handling a core restraint design as used in FFTF, and to compare the SASSYS/SAS4A results using this model to the empirical correlation presently being used to account for radial core expansion reactivity feedback to FFTF.

UK PubMed Central (United Kingdom)

Surveys were conducted in one urban and two rural regions of the United Republic of Cameroon to estimate the annual incidence of paralytic poliomyelitis. Three different survey methods were used: a...Full Text Available

CERN Document Server

In this report, I surveyed the cognitive radio technique in wireless networks. Researched several kinds of cognitive techniques about their advantages and disadvantages.

Science.gov (United States)

Two hundred eleven references from the period 1951 to 1978 are reviewed in this survey of literature on the thermal stability of jet aircraft fuels.

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

This report describes the results made in fulfillment of contract DE-FG26-02NT15451, ''Multicomponent Seismic Analysis and Calibration to Improve Recovery from Algal Mounds: Application to the Roadrunner/Towaoc Area of the Paradox Basin, Ute Mountain Ute Reservation, Colorado''. Optimizing development of highly heterogeneous reservoirs where porosity and permeability vary in unpredictable ways due to facies variations can be challenging. An important example of this is in the algal mounds of the Lower and Upper Ismay reservoirs of the Paradox Basin in Utah and Colorado. It is nearly impossible to develop a forward predictive model to delineate regions of better reservoir development, and so enhanced recovery processes must be selected and designed based upon data that can quantitatively or qualitatively distinguish regions of good or bad reservoir permeability and porosity between existing well control. Recent advances in seismic acquisition and ...

International Nuclear Information System (INIS)

The fission gas xenon bonded in bubbles, in pore, and in the lattice of mixed carbide fuels is measured by electron-probe microanalysis. Radial xenon distribution and release curves are determined and are calibrated by gas chromatography of the bonded fission gas and by burnup analysis in the respective pin sections of the irradiation experiments FR2 6A and 6C, Mol 11/K 2, and DFR 330/1. The results are correlated to the microstructure of the fuel, bonding medium, temperature, and burnup. (Auth.).

Energy Technology Data Exchange (ETDEWEB)

Substantial changes in the radial distribution function of amorphous Si films have been observed in neutron-diffraction studies. The spectra indicate changes in short-range order associated with an approx.11% modification in the bond-angle distribution width. The results allow the first direct comparison of structural and vibrational Raman probes of variations in local order in thin-film amorphous solids. Good agreement is obtained between the measured bond-angle variation and that based on Raman estimates.

Energy Technology Data Exchange (ETDEWEB)

In this paper, a new design methodology for determining the size, location, type and number of capacitors to be placed on a radial distribution system is presented. The objective is to minimize the peak power losses and the energy losses in the distribution system considering the capacitor cost. A sensitivity analysis based method is used to select the candidate locations for the capacitors. A new optimization method using a Genetic Algorithm is proposed to determine the optimal selection of capacitors. Test results have been presented along with the discussion of the algorithm.

International Nuclear Information System (INIS)

A formula for calculating the Dirac S-matrix for central Lorentz scalar and vector potentials is derived by use of a new amplitude-phase method. The derivation also makes use of certain invariants of the reduced 2-spinor radial Dirac equations.

International Nuclear Information System (INIS)

We investigate the effects of the velocity-dependent force on the magnetic form factors and magnetic moments of odd-Z nuclei. The form factors are calculated with the harmonic-oscillator wavefunctions. It is found that the contributions of the velocity-dependent force manifest themselves in the very large momentum transfer region (q?4 fm-1). In the low and medium q region the contributions of the velocity-dependent force are very small compared with those without this force. However, in the high-q region the contributions of the velocity-dependent force are larger than the normal form factors. The diffraction structures beyond the existing experimental data are found after the contributions of the velocity-dependent force are included. The formula of the correction to the single particle magnetic moment due to the velocity-dependent force is reproduced exactly ...

DEFF Research Database (Denmark)

BACKGROUND AND AIM OF THE STUDY: Abnormal flow conditions across aortic bioprosthetic valves may result in degenerative processes. Thus, it is important to implant biological valve prostheses with velocity profiles similar to those of native valves. The study aim was to compare blood velocity and velocity gradient profiles downstream of stented and stentless aortic valves implanted in pigs, and in native porcine valves. METHODS: Stented valve prostheses (Mitroflow, n = 7) or stentless valve prostheses (Solo, n = 5 or Toronto SPV, n = 7) were implanted into pigs; the native valve was retained in eight animals. After weaning the animals from cardiopulmonary bypass, cardiac magnetic resonance imaging was performed to determine the blood velocities and velocity gradient profiles. RESULTS: The native valves had a significantly lower peakvelocity (92 +/- 26 cm/s) than the artificial ...

Energy Technology Data Exchange (ETDEWEB)

This paper introduces a multichannel digital data acquisition system and examples of measurements with the system in seismic exploration using the high resolution seismic refraction method. The high resolution seismic refraction system performs analyses nearly automatically by using a computer after initial travel time has been read. Therefore, the system requires high-accuracy travel time data, for which a multichannel digital measuring instrument developed recently for seismic exploration using the refraction method has been used for the measurement. The specification specifies the number of channels at 144 as a maximum, a sampling time of 62.5 {mu}sec to 4 m sec, the maximum number of sampling of 80,000 samples, and gain accuracy of {plus_minus} 1%. The system was used for surveying a tunnel having a maximum soil cover of about 800 m. The traverse line length is about 6 km, the distance between vibration receiving points is 50 m, and the number of vibration ...

Science.gov (United States)

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Science.gov (United States)

No abstract available.

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

This report presents the preliminary findings of the first phase of the Environmental Survey of the US Department of Energy's (DOE) National Institute for Petroleum and Energy Research (NIPER), conducted February 29 through March 4, 1988. The Survey is being conducted by an interdisciplinary team of environmental specialists, led and managed by the Office of Environment, Safety and Health's Office of Environmental Audit. Team members are being provided by private contractors. The objective of the Survey is to identify environmental problems and areas of environmental risk associated with NIPER. The Survey covers all environmental media and all areas of environmental regulation. It is being performed in accordance with the DOE Environmental Survey Manual. The on-site phase of the Survey involves the review of existing site environmental data, ...

International Nuclear Information System (INIS)

Velocity field behind a flat plate, placed near the wall in a narrow channel as a simulant of a BWR fuel spacer, was measured by using a hot wire anemometer. It was found that not only the positions where the dead water region behind flat plate disappeared but also the locations where the velocity relaxation completed were almost independent of the width of the clearance, although the local average velocity and velocity fluctuation immediately downstream the flat plate were affected by the difference in the clearance. The transverse flow diversions in the channel cross section were evaluated from the shape of the average velocity profile. The decrease of local flow rate near the channel wall, which may causes the drift flow behind a flat plate, was encouraged as the drag of clearance increased. Attempts have been made to measure spanwise velocity in the narrow ...

Energy Technology Data Exchange (ETDEWEB)

The possibility of controlling the radial electric field of toroidal plasmas by injecting high energy electrons along the reversible loss cone orbit of the helical magnetic traps is investigated. It is well known that the radial electric field plays an important role in the confinement improvement scenario especially in the low collisional regime under the physics picture of neoclassical theory. For this purpose, it is made clear that the most suitable particles are transit particles, which show a transition from helically trapped orbits to blocked ones. It is also found that a parallel AC electric field launched from outside assists this transition and makes it possible for particles to penetrate deeply into the plasma. In addition we clarify that the viscosity of the plasma coupled with the helical field configuration provide a bifurcation of plasma states and its stable solution results in confinement improvement. (author)

CERN Document Server

New non-stationary non-contracted form of the erosive radially-slotted discharge as a thin round sheet with the current of the azimuth direction have been discovered, its existence beings stipulated by a radial transport-wave fluxes. Characteristic features of this discharge is self-confinement of the discharge current magnitude, corresponding decrease of the current pulse duration and occurrence of an energy and substance ejection with rather unusual properties. Measurements of kinetics of the discharge current, the plasma radiation intensity and an electrical probe signal, as well as the transmission electron microscope investigations of characteristic aerodisperse aggregates arising the erosive phase, have been carried out. The probe signal duration was about 10 times greater than that of the current; its kinetics was complicated suggesting existence in the slot of two components with fundamentally different properties and states of the ...

Energy Technology Data Exchange (ETDEWEB)

Radial sonic crystals (RSC) are fluidlike structures infinitely periodic along the radial direction that verify the Bloch theorem and are possible only if certain specially designed acoustic metamaterials with mass density anisotropy can be engineered (see Torrent and Sanchez-Dehesa 2009 Phys. Rev. Lett. 103 064301). A comprehensive analysis of two-dimensional (2D) RSC shells is reported here. A given shell is in fact a circular slab with a central cavity. These finite crystal structures contain Fabry-Perot-like resonances and modes strongly localized at the central cavity. Semi-analytical expressions are developed to obtain the quality factors of the different resonances, their symmetry features and their excitation properties. The results reported here are completely general and can be extended to equivalent 3D spherical shells and to their photonic counterparts.

International Nuclear Information System (INIS)

The operation and safety of both fossil-fuel and nuclear power stations depend on adequate cooling of the thermal source involved. This is usually accomplished using liquid coolants that are forced through the high temperature regions by a pumping system; this fluid then transports the thermal energy to another section of the power station. However, fluids that undergo boiling during this process create vapor that can be detrimental, and influence safe operation of other system components. The behavior of this vapor, or void, as it is generated and transported through the system is critical in predicting the operational and safety performance. This study uses two advanced penetrating radiation techniques, Real Time Neutron Radiography (RTNR), and High Speed X-Ray Tomography (HS-XCT), to examine void generation and transport behavior in a flow boiling system. The geometries studied were tube side flow boiling in a cylindrical configuration, and a similar flow channel with an internal ...

UK PubMed Central (United Kingdom)

We have previously shown that unloaded shortening velocity (V₀) of human plantar flexors can be determined in vivo, by applying the “slack test”...Full Text Available

Science.gov (United States)

The results of an experimental study of axial and crossflow velocity in a 7-pin wire wrapped bundle similar for FFTF fuel bundles are reported. The results are compared with the forced crossflow model of the COBRA-III C computer program. (JWR)

International Nuclear Information System (INIS)

The present emphasis on inherent safety for liquid-metal reactor designs has resulted in a need to represent the various reactivity feedback mechanisms as accurately as possible. The dominant negative reactivity feedback has been found to result from radial expansion of the core for most postulated anticipated transient without scram events. For this reasons, a more detailed model for calculating the reactivity feedback from radial core expansion, including subassembly bowing has been recently developed for use with the SASSYS/SAS4A code system. The purpose of this summary is to present an extension to the model so that it is more suitable for handling a core restraint design as used in the Fast Flux Test Facility (FFTF), and to compare the SASSYS/SAS4A results using this model to the empirical correlation presently being used to account for radial core expansion reactivity feedback in the FFTF.

Science.gov (United States)

... at the end of this report. A. Low-Velocity Impact of Composite Sandwich Panels In 2007, the PI developed analytical solutions ...

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

Changes in transverse phonon sound velocity were measured during low temperature irradiation of amorphous Pd{sub 80}Si{sub 20} with 3.5 MeV krypton ions. The sound velocity decreases as a function of the ion fluence and shows a tendency to saturate at large fluences at a relative change of {minus}4.7%. The changes in sound velocity were used to determine the changes in shear elastic constant and in Debye temperature both of which were in reasonable agreement with the value reported in the literature.

Energy Technology Data Exchange (ETDEWEB)

The title invention aims at a vibrations-free running of the flywheel to realize a high speed (18,000-20,000 revolutions per minute). The flywheel consists of a case which holds a central stator, a rotor and two ball-bearings. The ball-bearings have a first radial stiffness and are placed in between the rotor and an upper, respectively lower support bearer. The support bearers are supported on the stator with a second radial stiffness. The top and the bottom of the stator is connected to the case by means of a support with a third stiffness. 6 figs.

International Nuclear Information System (INIS)

XAFS data of metallic glass Al_0_._9_1La_0_._0_9 and a crystalline phase Al_1_1La_3 formed by annealing of the glass were measured at the La L_3 edge at T=12 K and analyzed using the radial distribution function method. The shortest La-Al distance appeared to be distinctively smaller within the glass than in the crystal. This difference decreases the disparity in size of La and Al in the alloy, allowing their mixing in the glassy state. ((orig.)).

Energy Technology Data Exchange (ETDEWEB)

The outward radial expansion of a free liquid annulus is a common problem of both earlier and current ICF blanket design. Whether the annulus fractures or not depends on the internal pressure and surface stability. In this paper a model based on incompressible cylindrically symmetric flow is used to get a theoretical solution similar to that of the Rayleigh's solution for bubble dynamics. The pressure inside the annulus is found positive all time but the peak is lowering during the expansion. Besides, both surfaces are Taylor stable during such motion. Thus, it is concluded that an annulus in outward radial motion will not cavitate or breakup.

International Nuclear Information System (INIS)

Differential cross sections have been measured for the elastic and inelastic scattering of 104 MeV alpha-particles from "9"0,"9"2Zr. The experimental data are analyzed in terms of coupled channels on the basis of a flexible anharmonic vibrator model and using different parametrizations of the radial shape of the extended optical potential. The results favour the squared Saxon-Woods type for the real part. Additionally to a radial momentum analysis of the real potentials a semimicroscopic folding model has been invoked for extracting isoscalar quadrupole and hexadecapole transition rates. (orig.).

Energy Technology Data Exchange (ETDEWEB)

Time resolved light scattering from laser-induced electrostrictive gratings was used for the determination of flow velocities in air at room temperature. By measuring the velocity profile across the width of a slit nozzle we demonstrated the high spatial resolution (about 200 mm) of this novel technique. (author) 3 figs., 1 ref.

Energy Technology Data Exchange (ETDEWEB)

Qualifying corrosion inhibitors for use in high velocity multiphase flowlines in arctic or subsea environments is discussed. The tests include high velocity flow loop corrosion tests, pumpability through 0.125 (0.318 cm) inch capillary at low temperatures, compatibility with Nylon 11, emulsion tendency testing, and partitioning characteristics. Laboratory and field data show the importance for using the above criteria for inhibitor selection.

UK PubMed Central (United Kingdom)

BackgroundDespite having the largest population in Africa, Nigeria has no accurate population based data to plan and evaluate eye care services. A national survey was undertaken...Full Text Available

Science.gov (United States)

This report gives the results of a survey of operational flue gas desulfurization (FGD) systems on coal-fired utility boilers in the United States. The FGD systems installed on Units 1 and 2 at the Bruce Mansfield Station of the Pennsylvania Power Company...

Energy Technology Data Exchange (ETDEWEB)

This paper describes a radiation shield verification survey of a large hot cell at the Fast Flux Test Facility (FFTF). The following aspects of the shield test are discussed: description of the FFTF; description of the hot cell; the test procedures; radiation protection, and the test results.

Science.gov (United States)

Survey - science for a changing world USGS Home Contact USGS Search USGS Hawaiian Volcano Observatory U.S. Geological Survey Open-File Reports 2007-1316 through 2007-1354...

Science.gov (United States)

The report, generated by a computerized data base system, presents a survey of operational and planned domestic utility flue gas desulfurization (FGD) systems, operational domestic particle scrubbers, and Japanese coal-fired utility FGD installations. It ...

UK PubMed Central (United Kingdom)

ObjectivePersons with chronic or recurrent pain frequently visit the emergency department (ED), yet little research examines this experience. We conducted this national survey to...Full Text Available

International Nuclear Information System (INIS)

Published density profiles and central velocity dispersions place important constraints on the stellar velocity ellipsoid and on the distribution of dark matter (DM) in the dwarf spheroidal galaxies Draco and Ursa Minor. Central velocity dispersions of 9 km/s are adopted for Draco and 11 km/s for Ursa Minor. Then, for an isotropic stellar velocity distribution, the central DM densities are 0.8 and 1.0 solar mass/cu pc, respectively, if visible and dark matter have the same core radius. If DM has a much larger core radius than visible matter but nevertheless dominates the potential, these densities are reduced by a factor of 2. Central DM densities can be lower than this only if the stellar velocity distribution is anisotropic. Simple two-component King models are used to investigate this and to look for the smallest DM densities that are consistent with the observations. 36 refs.

KoreaScience (Korea)

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Science.gov (United States)

... Keywords: Ferrocement; Floating concrete structures; Ships; Barges; and Offshore platforms. Descriptors : *REINFORCED ...

Energy Technology Data Exchange (ETDEWEB)

Prior to routine use, all newly installed x-ray machines must have a radiation-protection survey by a qualified expert. The survey is an evaluation of existing or potential radiation hazards associated with the use of diagnostic x-ray equipment under specific conditions. Such evaluation includes the measurement of exposure levels in the environment as well as environmental levels arising from operation of the equipment. The survey also includes an evaluation of the safety characteristics of the x-ray unit.

CERN Document Server

Sumedh Anathpindika surveys astronomy in India and finds a lively and developing community as well as great public interest.

National Aeronautics and Space Administration (NASA)

NASA's Glory spacecraft is equipped to survey and map aerosols in Earth's atmosphere during a mission marking the return to flight of the Taurus XL rocket.

Energy Technology Data Exchange (ETDEWEB)

In conventional microtremor prospecting methods, underground structure is estimated using the phase velocity of Rayleigh-wave only. However, it is considered that the underground structure can be estimated at a higher accuracy by using two phase velocities of Rayleigh-wave and Love-wave that directly reflects S-wave velocity structure. Therefore, three-component microtremor array observation of a circle (equilateral triangle) with the maximum radius of 40 to 250 m was carried out at the center of Morioka city. Analysis was carried out by means of extended space with autocorrelation to obtain phase velocities of Love- and Rayleigh-waves. The frequency zone of the obtained Rayleigh-wave phase velocity is 1.5 Hz to 8.6 Hz, and the phase velocity is 2670 m/s to 733 m/s. The frequency zone of the obtained Love-wave phase velocity is 3 Hz to 8.6 ...

Energy Technology Data Exchange (ETDEWEB)

The potential market for irradiated chicken breasts was investigated using a mail survey and a retail trial. Results from the mail survey suggested a significantly higher level of acceptability of irradiated chicken than did the retail trial. A subsequent market experiment involving actual purchases showed levels of acceptability similar to that of the mail survey when similar information about food irradiation was provided.

Energy Technology Data Exchange (ETDEWEB)

The ion-velocity dependence of the ionization probability for an atom ejected from a surface is examined by using a quantum approach in which the coupled motion between electrons and the outgoing nucleus is followed along the whole trajectory by solving the stationary Schroedinger equation. We choose a very-small-cluster-model system in which the motion of the atom is restricted to one dimension, and with energy potential curves corresponding to the involved channels varying appreciably with the atom position. We found an exponential dependence on the inverse of the asymptotic ion velocity for high emission energies, and a smoother behavior with slight oscillations at low energies. These results are compared with those obtained within a dynamical-trajectory approximation using either a constant velocity equal to the asymptotic ionic value, or expressions for the velocity derived from the eikonal ...

Energy Technology Data Exchange (ETDEWEB)

Faults are being actively investigated across Japan since the Great Hanshin-Awaji Earthquake. Discussed in this report is the application of the 3D near-surface reflection seismic survey in big cities. Data from trenching and drilling is used for the geological interpretation of the surroundings of a fault, and the reflection seismic survey is used to identify the position, etc., of the fault. In this article, when the results obtained from the experimental field are examined, it is found that the conventional 2D imaging reflection survey betrays the limit of its capability when the geological structure is complicated, that the 3D reflection seismic survey, on the contrary, is capable of high-precision imaging and, when augmented by drilling, etc., becomes capable of a more detailed interpretation, and that it also contributes effectively to the improvement of local disaster prevention in big cities. ...

Energy Technology Data Exchange (ETDEWEB)

Three popular imaging methods were used to carry out seismic migration from the Alberta foothills: Kirchhoff integral, reverse-time and explicit finite-difference migration methods. The imaging comparisons of reverse-time, Kirchhoff and f-x post-stack depth migration leads to the following conclusions. All of the three migration methods can provide acceptable and well-imaged intermediate results on the simplest model. Post-stack migration was not very sensitive to the accuracy of the velocity field once a reliable structural stack was available. With respect to the imaging accuracy and calculation cost, the Kirchhoff migration method seemed to be superior to reverse-time and f-x migration algorithms because its results on different kinds of velocity cases were basically kept coherent and consistent with the velocity model given by Mobil. Because of the lack of an accurate velocity field, reverse-time ...

International Nuclear Information System (INIS)

We study the spin dependence of accretion onto rotating Kerr black holes using analytic techniques. In its linear regime, angular momentum transport in MHD turbulent accretion flow involves the generation of radial magnetic field connecting plasma in a differentially rotating flow. We take a first principles approach, highlighting the constraint that limits the generation and amplification of radial magnetic fields, stemming from the transfer of energy from mechanical to magnetic form. Because the energy transferred in magnetic form is ultimately constrained by gravitational potential energy or Killing energy, the spin dependence of the latter allows us to derive spin-dependent constraints on the success of the accreting plasma to expel its angular momentum. We find an inverse relationship between this ability and black hole spin. If this radial magnetic field generation forms the basis for angular momentum transfer in ...

Science.gov (United States)

The visual outcomes of Acanthamoeba keratitis, a rare cause of corneal infection, can be devastating. This paper reports two contact lens wearers with severe pain and photophobia who presented to the emergency room. Biomicroscopy revealed radial keratoneuritis in both individuals. Tissue culture on a nonnutrient agar plate with Escherichia coli overlay resulted in a heavy growth of Acanthamoeba. The inpatient treatment included 0.02% polyhexamethylene biguanide, chlorhexidine, neomycin/polymyxin B/bacitracin (Neosporin), and oral fluconazole, which successfully controlled the corneal infection and improvement in the best corrected visual acuity in both patients. Infection did not recur during the 12-month follow-up period. Acanthamoeba keratitis can present as radial keratoneuritis, mimicking other common corneal infections resulting in diagnostic and treatment delays. Early diagnosis and prudent treatment of Acanthamoeba keratitis are the keys ...

International Nuclear Information System (INIS)

In the frame of the European Technology R and D programme for International thermonuclear experimental reactor (ITER) and in the area of high heat flux plasma facing components (HHFC), representative small-scale mock-ups were manufactured and tested to compare different concepts and joining technologies (i.e. active brazing, hot isostatic pressing (HIPping), diffusion bonding, etc.). On the basis of the results obtained by thermal fatigue tests, the monoblock concept resulted to be the most robust one, particularly when the HIPping manufacturing technology is used. Within this programme, ENEA developed an alternative technique for manufacturing plasma-facing components with a monoblock geometry of the ITER machine. The basic idea of this technique, named hot radial pressing (HRP), is to perform a radial diffusion bonding between the cooling tube and the armour tile by pressurising the internal tube only and by keeping the process parameters ...

Energy Technology Data Exchange (ETDEWEB)

In this work, the Calibration-Free approach for Laser-Induced Breakdown Spectroscopy (CF-LIBS) was applied for the first time to radially resolved spectra emitted by a laser-induced plasma. The radial profiles of plasma temperature and electron number density were used to calculate the local relative concentration of the elements of interest. We analyzed a set of profiles of the local spectral emission coefficient obtained previously by means of spatial deconvolution of the spectra from a copper-based alloy (Cu 93, Fe 5, Mn 1, Ni 1 wt.%) laser-induced plasma. A spatially integrated spectrum of the same plasma was also analyzed for comparison purpose. The relative abundance of the minor components Fe, Mn and Ni was calculated. The results obtained from the central region of the plasma were closer to the nominal concentrations than those obtained from the spatially integrated spectrum. However, an increasing deviation was observed towards the ...

International Nuclear Information System (INIS)

Based on the generalized gradient approximation (GGA) of density functional theory (DFT) and the full-potential linearized augmented plane wave (FLAPW) at the level including all electrons, the lattice parameters of graphite are calculated and optimized. Some elastic wave velocities transmitted in graphite are deduced. Using the methods of elastic wave velocity method and the atomic displacement method, the Debye frequency of graphite is obtained. The standard heat capacity, entropy, sublimation enthalpy of graphite is deduced at 289.5 k and 1 atm. The calculated results are discussed and compared with experimental data. (authors)

Energy Technology Data Exchange (ETDEWEB)

The effect of nonequilibrium diffusional flow on detonation velocities in composite explosives is examined. Detonation conditions are derived for complete equilibrium, temperature and pressure equilibrium, and two forms of pressure equilibrium. Partial equilibria are associated with systems which have not had sufficient time for transport to smooth out the gradients between spatially separate regions. The nonequilibrium detonation conditions are implemented in the CHEQ equation of state code. We show that the detonation velocity decreases as the non-chemical degrees of freedom of the explosive are allowed to equilibrate. It is only when the chemical degrees of freedom are allowed to equilibrate that the detonation velocity increases. {copyright} {ital 1998 American Institute of Physics.}

International Nuclear Information System (INIS)

The driving system of a Moessbauer spectrometer is described. The system comprises a minivibrator, a digital generator of the reference velocity signal, and circuits for controlling the vibrator. The reference velocity signal is stored by the control computer in an intermediate storage. The feedback in the control circuits includes correction for nonlinearity of the driving facility. A Moessbauer spectrometer which is equipped with this driving system exhibits a velocity scale nonlinearity below 0.1%. The resonance line width for sodium nitroprusside is 0.27 #+-# 0.01 mm/s. (author). 6 figs., 8 refs.

Scientific Electronic Library Online (English)

Abstract in english Numerical solutions for the effects of radiation on a MHD convective heat transfer past a semi-infinite porous plate with a magnetic field are obtained. It is assumed that the porous plate moves with a constant velocity in the direction of fluid flow, and the free stream velocity follows the exponentially increasing small perturbation law. The magnetic field acts perpendicular to the porous surface which absorbs the fluid with a suction velocity varying with time. The gov (more) erning equations for the flow are transformed into a system of nonlinear ordinary differential equations by perturbation technique and then are solved numerically by using the shooting method. The effects of the various parameters on the velocity, temperature profiles as well as the surface skin-friction and surface heat transfer are illustrated graphically.

Science.gov (United States)

... 24 1.6. Storm Movement .. .. . ... W hydrometeor fall speed containing the vertical velocity and the particle terminal fall speed (= w + V) ...

Energy Technology Data Exchange (ETDEWEB)

It is shown that plasma viscosity does not influence the magnetic island rotation directly. Nevertheless, it leads to nonstationarity of the plasma velocity. This nonstationarity is the reason of the viscosity effect on island rotation. (author)

Science.gov (United States)

Specialized tests can be designed to study impingement-corrosion, erosion- corrosion, cathodic protection systems, cavitation and other velocity effects. ...

International Nuclear Information System (INIS)

Determining the radial distribution of the thermal neutron field in the core of the Dalat reactor was done by the Cu foil activation method. The measured data were fitted by the least square method to determine some physical parameters of the reactor, as follows: 1. Laplacian: B_r"2 = (84.6 +- 5.5)10_-_4/,cm"2. 2. The effective radius: R_e_f_f = (27.6 +- 1.0)cm. 3. The extrapolation distance: #lambda#_r = (8.7 +- 1.0)cm. 4. The unequal coefficient of the effective multiplication: k_r = 1.77 +- 0.11. (author). 3 refs., 4 figs., 1 tab.

International Nuclear Information System (INIS)

The noncrystalline compounds MoS_3, WS_3 and MoSe_3 were studied by X-ray diffraction. From the diffuse intensities radial distribution functions were computed and interpreted in terms of pair distribution functions. The substances are built up by microcrystallites which contain three metal atoms and are bridged statistically to each another. The shortest metal chalcogen distances d(MoS) approximately d(WS) = 2.40 +- 0.05 A and d(MoSe) = 2.50 +- 0.05 A are significantly longer than in MS- or MSe compounds with a d"0 configuration of the metal respectively and metal-metal distances within the microcrystallites are less than 3 A. (author).

International Nuclear Information System (INIS)

The authors describe a new method which makes it possible to determine the radial distribution of the diffuse component of galactic gamma rays outside the solar circle. They use the observation that a good correlation exists between gamma-ray intensities and total column densities of the local interstellar gas and that the fractional column density of H_2<0.1 HI outside the solar circle. Thus the gamma-ray intensities are shown to be proportional to N(HI). The authors use the kinematics of the HI to determine the distances from which various fractions of the emission originate in the second and third galactic quadrants. Preliminary results of our analysis show that a significant flux of gamma rays originates from distances as large as 18 kpc from the galactic centre. (Auth.).

CERN Document Server

We outline to the community the value of a Magellanic Clouds Survey that consists of three components: I) a complete-area, high resolution, multi-band UV-near-IR broadband survey; II) a narrowband survey in 7 key nebular filters to cover a statistically significant sample of representative HII regions and a large-area, contiguous survey of the diffuse, warm ISM; and III) a comprehensive FUV spectroscopic survey of 1300 early-type stars. The science areas enabled by such a dataset are as follows: A) assessment of massive star feedback in both HII regions and the diffuse, warm ISM; B) completion of a comprehensive study of the 30 Doradus giant extragalactic HII region (GEHR); C) development and quantitative parameterization of stellar clustering properties; D) extensive FUV studies of early-type stellar atmospheres and their energy distributions; and E) similarly extensive FUV ...

Energy Technology Data Exchange (ETDEWEB)

This document contains summary reports of stream habitat surveys, conducted in the Cowlitz River basin, by the Bureau of Fisheries (BOF, now National Marine Fisheries Service) from 1938-1942. These surveys were part of a larger project to survey streams in the Columbia River basin that provided, or had provided, spawning and rearing habitat for salmon and steelhead. The purpose of the survey was, as described by Rich, [open quotes]to determine the present condition of the various tributaries with respect to their availability and usefulness for the migration, breeding, and rearing of migratory fishes[close quotes]. Current estimates of the loss of anadromous fish habitat in the Columbia River Basin are based on a series of reports published from 1949-1952 by the U.S. Fish and Wildlife Service. The reports were brief, qualitative accounts of over 5000 miles of stream surveys ...

Energy Technology Data Exchange (ETDEWEB)

One of the most important goals of the Italian survey, initiated in 1989, was to promote ad hoc policies to reduce radon exposure of the population. In the survey a statistical representative sample of 5000 dwellings was chosen; two six-month measurements were made of the indoor radon concentration, in combination with one six-month measurement of gamma exposure. The results of the radon concentration measurements are reported here: they refer to 80% of the sample. The annual mean value was 81.5Bq.m{sup -3}, which is higher than that reported for other industrialised countries. (author).

Environmental Research Database

SummaryBTO Winter Gull Roost Survey (WinGS): 2004/07. To assess the significance of Northern Ireland gull populations Background The BTO has organised national surveys of winter gull roosts each decade since 1953 in order to estimate numbers of wintering gulls. The last survey took place in January 1993, during which over 2.5 million gulls were counted in Great Britain. A further 19,000 gulls were also counted in Northern Ireland, 3,850 in the Isle of Man and 8,500 in the Channel Islands. (The re [continued...

Science.gov (United States)

as manufacturing plants and laboratories, including the Chemical Laboratory at the House of David in Benton Harbor, Michigan. Built in America: Historic Building Buildings Survey/...

International Nuclear Information System (INIS)

German translation of the publication 'The evaluation of risks from radiation' published in 1965 by the International Commission on Radiological Protection. In a survey, genetic and somatic risks from radiation are presented and explained. (HP).

CERN Document Server

The Quantum Mechanics Conceptual Survey (QMCS) is a 12-question survey of students' conceptual understanding of quantum mechanics. It is intended to be used to measure the relative effectiveness of different instructional methods in modern physics courses. In this paper we describe the design and validation of the survey, a process that included observations of students, a review of previous literature and textbooks and syllabi, faculty and student interviews, and statistical analysis. We also discuss issues in the development of specific questions, which may be useful both for instructors who wish to use the QMCS in their classes and for researchers who wish to conduct further research of student understanding of quantum mechanics. The QMCS has been most thoroughly tested in, and is most appropriate for assessment of (as a posttest only), sophomore-level modern physics courses. We also describe testing with students in ...

UK PubMed Central (United Kingdom)

A questionnaire survey undertaken among 142 schoolteachers in North Staffordshire revealed most of the respondents did not feel confident when teaching children who had epilepsy and a minority considered...Full Text Available

Science.gov (United States)

Health information technology initiatives created the framework for a national health information infrastructure that concomitantly fostered a need to build intellectual capacity within our current and future health information management (HIM) work force. Results from the 2008 HIM Educator Survey are discussed. Developed for voluntary electronic participation, the survey comprised a series of questions about educators' professional interests and responsibilities. Summary data from the 402 respondents are provided and highlight areas such as academic rank, teaching status, salary range, levels of interest in various issues, and use of virtual learning tools. Data from this survey provide insights into the concerns and challenges many HIM educators face in today's training institutions and suggest implications for future directions in work force training and professional development within the HIM field. PMID:19424453

UK PubMed Central (United Kingdom)

A survey was carried out in a steel foundry in Brisbane to evaluate the nature and frequency of respiratory symptoms and to assess ventilatory function. The foundry used many moulding processes including...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

A survey of wetlands on the Oak Ridge Reservation (ORR) was conducted in 1990. Wetlands occurring on ORR were identified using National Wetlands Inventory (NWI) maps and field surveys. More than 120 sites were visited and 90 wetlands were identified. Wetland types on ORR included emergent communities in shallow embayments on reservoirs, emergent and aquatic communities in ponds, forested wetland on low ground along major creeks, and wet meadows and marshes associated with streams and seeps. Vascular plant species occurring on sites visited were inventoried, and 57 species were added to the checklist of vascular plants on ORR. Three species listed as rare in Tennessee were discovered on ORR during the wetlands survey. The survey provided an intensive ground truth of the wetlands identified by NWI and offered an indication of wetlands that the NWI remote sensing techniques did not detect.

Science.gov (United States)

The automatic weather stations at the Australian stations (Casey, Davis, ... This metadata record describes Simone Ingham's survey of vegetation sampling ...

Science.gov (United States)

... far superior in its annual and sick leave policies. ... fair treatment with regard to leave requests, discipline ... Fifty-six percent of FERS employees use TSP ...

Science.gov (United States)

Sep 21, 2007... at night," said Glen Cushing of the U.S. Geological Survey's Astrogeology Team and of Northern Arizona University, Flagstaff, Ariz. ...

Science.gov (United States)

Group deal delay solution has fit 42 psec with 2.4% outliers. Group delay ambiguities with spacing 3.9 ns (another world record!) were successfully resolved. ...

Science.gov (United States)

An in/depth industrial hygiene survey of exposures to phosphine during the use of aluminum phosphide was conducted as part of a survey on exposure to grain fumigants. Area monitoring and breathing-zone sampling for phosphine were conducted during the addition of aluminum phosphide to grain during turning operations; source samples and peak personal exposures were also analyzed. Major sources of personal exposure included the escape of air from the bin headspace during filling with treated grain, filling and emptying of the phosphide pellet dispenser, and infiltration from the treated grain bin and from the pellet dispenser itself into adjacent air space. Relatively good dust control was indicated by the total dust samples collected during the survey. Measures recommended by the author are in the report.

Science.gov (United States)

... 4 II. INERTIAL NAVIGATION ERROR EQUATIONS ..... 5 ... 4- Page 20. Chapter II INERTIAL NAVIGATION ERROR EQUATIONS ...

Science.gov (United States)

The initial phase of this study consisted of a survey of existing FGD systems used on larger combustion processes in the NATO countries and Japan.

Science.gov (United States)

9-foot 9-inch blocks of concrete with asphaltic-filled expansion joints. The concrete was placed on 4 to 6 inches of gravel or #4 stone. ...

Science.gov (United States)

No abstract available.

CSIR Research Space (South Africa)

Full Text Available

Science.gov (United States)

Government policies that encourage exploitation--in particular excessive logging and clearing for ranches and farms--are largely to blame for the accelerating destruction of tropical forests. This paper surveys the problem in detail and briefly recommends potential solutions.

Science.gov (United States)

... AEC - Atomic Energy Commission (see CFSTI) AERE Harwell Lib The Librarian AERE, Ministry of Supply Harwell, Didcot, Birks England AF ...

CERN Document Server

Large optical surveys provide an unprecedented census of galaxies in the local Universe, forming an invaluable framework into which more detailed studies of objects can be placed. But how useful are optical surveys for understanding the co-evolution of black holes and galaxies, given their limited wavelength coverage, selection criteria, and depth? In this conference paper I present work-in-progress comparing optical and mid-IR diagnostics of three "unusual" low redshift populations (luminous Seyferts, dusty Balmer-strong AGN, ULIRGs) with a set of ordinary star-forming galaxies from the SDSS. I address the questions: How well do the mid-infrared and optical diagnostics of star formation and AGN strength agree? To what extent do optical surveys allow us to include extreme, dusty, morphologically disturbed galaxies in our "complete" census of black hole-galaxy co-evolution?

Science.gov (United States)

... Aerial photographs were provided by Mr. Grover P. ... Dr. Beverely J. Watkins conducted the records search and wrote the historic research. x,/ ...

International Nuclear Information System (INIS)

New non-collinear schemes are suggested for transverse velocity modulation of electron beams and for the generation of coherent spontaneous radiation by these transversely modulated beams. It is shown that due to the non-collinearity some orders of magnitude enhancement can be achieved for the coherent spontaneous radiation (CSR) power at both the fundamental and harmonic frequencies.

British Library Electronic Table of Contents (United Kingdom)

Parameters of the vortex air flow in an isothermal model of the cyclone chamber are studied. The effect of the air velocity in nozzles on the values and character of the distribution of pressure and tangential and longitudinal velocities of air in the chamber is determined. Numerical modeling of the flow is performed, and it is shown that numerical calculation by the k-w turbulence model is in agreement with experimental data.

International Nuclear Information System (INIS)

The motions of a classical free spinning point particle are extended to include the range of superluminal velocities. There is no formal change in the constraint-dependent functional relationship between observable mass and spin, i.e., trajectory, accompanying this extension. However, the theory now permits the specification, for superluminal velocities, of a linearly rising trajectory and naturally yields tachyon confinement. Therefore, unlike their subluminal counterparts, these tachyons can be considered candidates for elementary particle constituents.

CERN Document Server

Using spectral hole-burning-based ultraslow group velocity in a dilute solid medium, we report enhanced photon echo efficiency three orders of magnitude higher than that in a nonslow light regime. The enhancement is due to exponentially increased absorption of an optical data pulse owing to the enhanced photon-atom interaction in an ultraslow light regime, whereas echo reabsorption is negligibly small due to group-velocity dependent population depletion.

Energy Technology Data Exchange (ETDEWEB)

The seismic reflection exploration technique which is one of the geophysical methods for oil exploration became effectively to image the subsurface structure with rapid development of computer. As a tool to perform seismic inversion, seismic forward modeling program using ray tracing should be developed. In this study, we have developed the algorithm that is to calculate the travel time of the complex geological structure using ray tracing by subdividing the geologic model into triangular element (finite element) having the constant velocity. We can analytically calculate Jacobian with some information by this current ray tracing. With this Jacobian, we will develop new algorithm which is to obtain geological properties and to image the subsurface. Since the FEM (Finite Element Method) ray tracing we have developed goes well the inverse velocities structure, we can apply the inversion problem to complex geological model. For the convenience of ...

International Nuclear Information System (INIS)

Transition rates for electrons in the superheavy elements Z = 114, 126, 134, 145, 164 and 173 are calculated. K, L and M-shells are considerd as final states. The 2s - 1s stransition of multipolarity M1 is dominant for Z = 173 with a transition time of 10"-"1"8s. The radial expectation values and #sq root# are given. (orig.).

Energy Technology Data Exchange (ETDEWEB)

The general relativistic version is developed for Robertson's discussion of the Poynting-Robertson effect that he based on special relativity and Newtonian gravity for point radiation sources like stars. The general relativistic model uses a test radiation field of photons in outward radial motion with zero angular momentum in the equatorial plane of the exterior Schwarzschild or Kerr spacetime.

Energy Technology Data Exchange (ETDEWEB)

The motion of a test particle moving in an interior static spherically symmetric geometry is investigated. The author concludes that an oscillatory motion with the test particle changing its motion from a free fall towards the center to an outward radial motion can not exist for any static interior spherically symmetric model.

International Nuclear Information System (INIS)

The Klein-Gordan equation in the background of the Schwarzschild curved space-time is considered and the scattering of radial tardyons and tachyons from a black hole is studied. It is shown that black holes of mass below 7x10"1"4g may contain bound states of tardyons of pion mass which will be unstable on account of the presence of an attractive r"-"4 term. (author).

CERN Document Server

A general theorem on the GBDT version of the B\\"acklund-Darboux transformation for systems rationally depending on the spectral parameter is treated and its applications to nonlinear equations are given. Explicit solutions of direct and inverse problems for Dirac-type systems, including systems with singularities, and for the system auxiliary to the $N$-wave equation are reviewed. New results on explicit construction of the wave functions for radial Dirac equation are obtained.

International Nuclear Information System (INIS)

Impact of apparatus dead time on the accuracy of measurement of radial distribution of the radiation attenuation factor in the roentgen computer tomography for rotation bodies is studied. Analytical expressions are obtained. Calculations of the threshold loads for radiometric detectors, providing for the accuracy of measurement at the stage of designing the tomographic complex detecting unit, are obtained

Energy Technology Data Exchange (ETDEWEB)

Compton scatter tomography utilizes the electronic collimation characteristics available through the Compton scattering angle-energy correlation to obtain tomographic images. In this work we present particular aspects of the technique, which are relevant to the inverse radiation transport problem of reducing marginal projection data to radial two-phase flow regime maps. The results indicate a viable technique for the tomographic imaging of tow-phase flow using practical source strengths and reasonably few detectors.

CERN Document Server

The properties of the highest velocity ejecta of normal Type Ia supernovae (SNe Ia) are studied via models of very early optical spectra of 6 SNe. At epochs earlier than 1 week before maximum, SNe with a rapidly evolving Si II 6355 line velocity (HVG) have a larger photospheric velocity than SNe with a slowly evolving Si II 6355 line velocity (LVG). Since the two groups have comparable luminosities, the temperature at the photosphere is higher in LVG SNe. This explains the different overall spectral appearance of HVG and LVG SNe. However, the variation of the Ca II and Si II absorptions at the highest velocities (v >~ 20,000 km/s) suggests that additional factors, such as asphericity or different abundances in the progenitor white dwarf, affect the outermost layers. The C II 6578 line is marginally detected in 3 LVG SNe, suggesting that LVG undergo less intense burning. The ...

CERN Document Server

We present deep optical long-slit spectra of 17 edge-on spiral galaxies of intermediate to late morphological type, mostly parallel to their major axes and in a few cases parallel to the minor axes.The line-of-sight stellar kinematics are obtained from the stellar absorption lines using the improvedc ross-correlation technique. In general, the stellar kinematics are regular and can be traced well into the disc-dominated region. The mean stellar velocity curves are far from solid-body, indicating that the effect of dust extinction is not large. The line-of-sight stellar disc velocity dispersion correlates with the galaxy maximum rotational velocity, but detailed modeling is necessary to establish whether this represents a physical relation. In four spirals with a boxy- or peanut-shaped bulge we are able to detect asymmetric velocity distributions, having a common signature with projected radius in the ...

Energy Technology Data Exchange (ETDEWEB)

A seismic line was acquired by ARCO Exploration Company in 1977 in southern Freemont County and extends northeast from the deepest part of the Green River basin across the Wind River thrust onto crystalline basement rocks of the Wind River Mountains. A COCORP line across the area has been discussed previously, but the ARCO line shows more detailed information beneath the thrust. The seismic line is significant because it shows a strong reflection at the base of the Precambrian granite, which overlies a sedimentary rocks of the northern Green River basin. It also illustrates an apparent anticline beneath the thrust fault which is the result of lateral velocity variation caused by a shallow wedge of low-velocity Miocene sediments superimposed on a velocity pull-up related to the high-velocity Precambrian granite. The effects of the velocity variations can be analyzed by ray tracing ...

Energy Technology Data Exchange (ETDEWEB)

The two-dimensional Eulerian hydrodynamic code 2DE with the shock initiation of heterogeneous explosive burn model called Forest Fire, is used to model numerically the interaction of jets of steel, copper, tantalum, aluminum, and water with steel, water, and explosive targets. The calculated and experimental critical condition for propagating detonation may be described by the Held V/sup 2/d expression (jet velocity squared times the jet diameter). In PBX 9502, jets initiate an overdriven detonation smaller than the critical diameter, which either fails or enlarges to greater than the critical diameter while the overdriven detonation decays to the C-J state. In PBX 9404, the jet initiates a detonation that propagates only if it is maintained by the jet for an interval sufficient to establish a stable curved detonation front. The calculated penetration velocities into explosives, initiated by a low-velocity jet, are ...

International Nuclear Information System (INIS)

In the present study an estimate is made of the malignancy significant dose from external beam radiotherapy in New Zealand utilizing data obtained in a survey conducted in 1975. This survey had been designed to assess genetically significant dose. A weighted effective dose equivalent is derived from the malignancy significant dose for direct comparison with mean per capita effective dose equivalents arising from other sources of radiation. 14 refs., 1 fig., 8 tabs.

International Nuclear Information System (INIS)

Naturally occurring radioactive materials (NORM) in seven new type wall materials were surveyed. The radioactivity was determined with HPGe-#gamma# spectrometer. The red mud has the highest radioactivity concentration, followed by slag building blocks, fly-ash building blocks (bricks), gangue bricks and light weight board materials, gypsum blocks. Fly-ash and slag contain higher NORM, which contributes the major part of the radioactivity in new wall materials. (authors)

Science.gov (United States)

The report gives results of a second survey of the flue gas desulfurization (FGD) system on Unit 1 of Kansas City Power and Light Co.'s La Cygne Station. The FGD system, first started up in February 1973 and commercially available in June 1973, uses a lim...

Science.gov (United States)

The report gives results of a survey of the flue gas desulfurization (FGD) systems at Kansas Power and Light Co.'s Lawrence Power Station. The systems utilize boiler injection of pulverized limestone, followed by tail-end wet scrubbing: unit 4, with a net...

Science.gov (United States)

Experiments contributing to the understanding of the aerodynamics of airfoils operating in the vertical axis wind turbine (VAWT) environment are described. These experiments are ultimately intended to reduce VAWT cost of energy and increase system reliability. They include chordwise pressure surveys, circumferential blade acceleration surveys, effects of blade camber, pitch and offset, blade blowing, and use of sections designed specifically for VAWT application.

Energy Technology Data Exchange (ETDEWEB)

Motivation is given for a technique to more thoroughly test semiconductor equipment control systems. A description is given of a simulator-based control system testing technique. Potential benefits that could be realized by using this technique in the semiconductor industry as well as benefits documented by using this technique in other industries are described. Specific requirements for using the technique in the semiconductor industry are outlined. A summary of a survey of nine commercial simulation systems is given. Finally, the outcome of the survey is compared with the requirements for using the technique.

Energy Technology Data Exchange (ETDEWEB)

With reference to three hypotheses on the causes of forest decline, the manifold uses of forest decline surveys are demonstrated. Hypothesis no. 1: Forest disease from high-voltage transmission lines; hypothesis no. 2: Forest disease as the consequence of damage from micorrhizas; hypothesis no. 3: Radioactivity as the cause of the increased incidence of forest disease. (orig./MG)

Energy Technology Data Exchange (ETDEWEB)

Design tools that are currently available for use with microcomputers to assist in designing energy-efficient daylighted buildings are presented. The information presented was gathered as a part of a telephone survey to design tool developer conducted over a six month period. The matrix is but one of five categories of tools. The other four were nomographs, protractors/tables, minis, and main frame computer programs. Information is provided to encourage interested design professionals, educators and students to communicate directly with design tool representatives.

British Library Electronic Table of Contents (United Kingdom)

A survey to assess mentoring experiences and attitudes towards work of Pennsylvania academic librarians was conducted in September 2006 with questions concerning mentoring experiences, work experiences, and attitudes towards work. Results of the survey are analyzed for differences among those librarians responding, especially generational differences, and implications for professional associations when developing mentoring programs are discussed.

CERN Document Server

The title refers to the area of research which studies infinite groups using measure-theoretic tools, and studies the restrictions that group structure imposes on ergodic theory of their actions. The paper is a survey of recent developments focused on the notion of Measure Equivalence between groups, and Orbit Equivalence between group actions. We discuss known invariants and classification results (rigidity) in both areas.

CERN Document Server

For purposes of designing targeted cataclysmic variable (CV) detection surveys and interpreting results of other projects with many CV detections such as the ChaMPlane Survey, we have created a model of the CV distribution in the Galaxy. It is modeled as a warped, flared exponential disk with a gaussian vertical distribution. Extinction is based on a detailed Galactic dust and gas model. A luminosity function for CVs is also incorporated, based on a smoothed version of published data. We calculate predicted field detection rates as a function of the limiting magnitude expected for the detecting system (i.e. WIYN/Hydra or NOAO 4m/Mosaic). Monte-Carlo techniques are used to assess statistical fluctuations in these rates. We have created maps of the expected CV distribution for the full non-bulge Galactic plane (20Survey and future CV surveys. Assuming ...

International Nuclear Information System (INIS)

An aerial radiological survey of the Oak Ridge Reservation (ORR) and surrounding area in Oak Ridge, Tennessee, was conducted during the period March 30 to April 14,1992. The purpose of the survey was to measure and document the terrestrial radiological environment of the Oak Ridge Reservation for use in environmental management programs and emergency response planning. The aerial survey was flown at an altitude of 150 feet (46 meters) along a series of parallel lines 250 feet (76 meters) apart and included X-10 (Oak Ridge National Laboratory), K-25 (former Gaseous Diffusion Plant), Y-12 (Weapons Production Plant), the Freels Bend Area and Oak Ridge Institute for Science and Education, the East Fork Poplar Creek (100-year floodplain extending from K-25 to Y-12), Elza Gate (former uranium ore storage site located in the city of Oak Ridge), Parcel A, the Clinch River (river banks extending from Melton Hill Dam to the city of ...

Energy Technology Data Exchange (ETDEWEB)

Two-phase flow in horizontal parallel channels has been experimentally investigated under fuel cell related operating conditions. Pronounced hysteresis is observed in the pressure drop versus flow characteristic curve when starting from either flooded or dry conditions. When gas is introduced into channels initially filled with water (flooded initial condition), both gas and liquid tend to flow predominantly in one channel at low gas or liquid flow velocities. As the gas flow velocity increases, even distribution of gas and liquid flow in both channels is observed, accompanied with a sudden decrease in the pressure drop. On the other hand, even gas and liquid flow distribution between both channels is found at comparatively lower gas flow velocities when starting with dry-gas flow conditions with liquid introduced into channels filled with gas (stratified flow regime). The flow regimes of this system are visualized in plots ...

Energy Technology Data Exchange (ETDEWEB)

The purpose of this thesis is to study the behaviour of the simultaneous flow of oil and water in horizontal pipes. In this connection, two test facilities are used. Both facilities have horizontal test sections with inner pipe diameters equal to 2 inches. The largest facility, called the model oil facility, has reservoirs of 1 m{sub 3} of each medium enabling flow rates as high as 30 m{sub 3}/h, which corresponds to mixture velocities as high as 3.35 m/s. The flow rates of oil and water can be varied individually producing different flow patterns according to variations in mixture velocity and input water cut. Two main classes of flows are seen, stratified and dispersed. In this facility, the main focus has been on stratified flows. Pressure drops and local phase fractions are measured for a large number of flow conditions. Among the instruments used are differential pressure transmitters and a traversing gamma densitometer, respectively. The ...

Energy Technology Data Exchange (ETDEWEB)

A stochastic wind simulation for VAWTs (VSTOC) has been developed which yields turbulent wind-velocity fluctuations for rotationally sampled points. This allows three-component wind-velocity fluctuations to be simulated at specified nodal points on the wind-turbine rotor. A first-order convection scheme is used which accounts for the decrease in streamwise velocity as the flow passes through the wind-turbine rotor. The VSTOC simulation is independent of the particular analytical technique used to predict the aerodynamic and performance characteristics of the turbine. The VSTOC subroutine may be used simply as a subroutine in a particular VAWT prediction code or it may be used as a subroutine in an independent processor. The independent processor is used to interact with a version of the VAWT prediction code which is segmented into deterministic and stochastic modules. Using VSTOC in this fashion is very efficient with ...

International Nuclear Information System (INIS)

This paper describes a series of tests investigating two-phase flow regimes in a transparent model of a PWR hot leg. Test conditions were selected to cover a wide range of gas and liquid superficial velocities (.01 m/s 2 m/s) were also performed for comparison with semi-analytical predictions. Results include average void fractions, flow rates, and visual characterizations of the two-phase flow phenomena. Results show generally good agreement with Taitel and Duckler flow regime map and Zuber-Findlay correlation for average void fraction in vertical pipes. Results also indicate that flow regimes and collapsed liquid level (void fraction) are more strongly dependent on air flow rate (air superficial velocity) than water flow rate (water superficial velocity).

Energy Technology Data Exchange (ETDEWEB)

This paper describes how confidence intervals can be calculated for radiofrequency emitter position estimates based on time-of-arrival and frequency-of-arrival measurements taken at several satellites. These confidence intervals take the form of 50th and 95th percentile circles and ellipses to convey horizontal error and linear intervals to give vertical error. We consider both cases where an assumed altitude is and is not used. Analysis of velocity errors is also considered. We derive confidence intervals for horizontal velocity magnitude and direction including the case where the emitter velocity is assumed to be purely horizontal, i.e., parallel to the ellipsoid. Additionally, we derive an algorithm that we use to combine multiple position fixes to reduce location error. The algorithm uses all available data, after more than one location estimate for an emitter has been made, in a mathematically optimal way.

British Library Electronic Table of Contents (United Kingdom)

Abstract Suspension of solids in stirred reactor is widely used for catalytic reactions, dissolution, etc. Quality of solid suspension is an important parameter required for the reliable design, optimum performance, and scale up of the system. Quality of suspension depends on local characteristics of solid velocity and hold up profiles. The present work was focused on investigating quality of solid suspension using ultrasound velocity profiler (UVP) measurements and CFD simulations. The slip velocity measurements carried out with UVP were used to evaluate different drag correlations used in CFD simulations. Results discussed in this work would be useful for extending the applications of CFD models for simulating large stirred slurry reactors.

British Library Electronic Table of Contents (United Kingdom)

We investigate two routes to obtain negative group velocity bands in two-dimensional phononic crystal structures. The negative dispersion originates from the resonances of sub-wavelength building blocks and as such, the system should be regarded as acoustic metamaterials. The first kind of acoustic metamaterial exhibits effectively negative bulk modulus and negative mass density simultaneously. Monopolar and dipolar Mie resonances are combined to achieve an effective medium with negative refractive index. In particular, we present a double negative metamaterial for airborne sonic waves. We then show that we can obtain negative group velocity from quadrupole resonances, and the result is explained using the quasi-static approximation. The negative dispersion in quadrupole bands cannot be de...

British Library Electronic Table of Contents (United Kingdom)

An analysis is presented for the effects of chemical reaction and thermal radiation on hydromagnetic free convection heat and mass transfer for a micropolar fluid via a porous medium bounded by a semi-infinite vertical porous plate in the presence of heat generation. The plate moves with a constant velocity in the longitudinal direction and the free stream velocity follows an exponentially small perturbation law. A uniform magnetic field acts perpendicularly to the porous surface in which absorbs the micropolar fluid with a suction velocity varying with time. Analytical expressions are computed numerically. Numerical calculations are carried out the purpose of the discussion of the results which are shown on graphs and the effects of the various dimensionless parameters entering into the p...

Energy Technology Data Exchange (ETDEWEB)

In the paper presented, an attempt is made to describe quantitatively the room air motion by diffuse air distribution. Since solving the problem theoretically, seems to be hopeless at present, only an experimental solution seems to promise success. Experiments with diffuse air distribution offer suitable preconditions. With this kind of air introduction into the room, a relatively regular distribution of room air motion can be expected. A further simplification will be achieved by isotherme flow conditions. The first goal of the experiments was to establish whether the velocities measured are reproducible to demonstrate, and can be brought into a functional connection. The room air motion is a measured value which changes temporarily and locally quite largely, far more than is customary with technical measurements. From there, a second task arises, i.e. to evaluate the fluctuation of the velocity registered by its quantity in an appropriate ...

International Nuclear Information System (INIS)

Stellar rotation velocities and velocity dispersions have been measured along the major and minor axes of NGC 4594 with the Canada-France-Hawaii Telescope. The observations show the kinematic signature of a nuclear disk of stars superposed on the bulge (Fig. 1). Apart from its larger size, this is similar to the nucleus of M31. It rotates rapidly: the apparent rotation curve reaches an inner maximum of V 231 #+-# 7 km s"-"1 at r = 5.''0. The apparent velocity dispersion falls from #sigma# = 250 #+-# 7 km s"-"1 at the center to 181 #+-# 6 km s"-"1 at r = 3.''7. (author).

British Library Electronic Table of Contents (United Kingdom)

Dispersal can be regarded as a process operating both between and within patches of suitable habitat. For uncontrolled dispersal processes, the risk of crossing the borders of the habitat patch and arriving in the unsuitable landscape matrix will increase with decreasing patch area, in particular when the distance between isolated habitat patches is larger than the species' average dispersal capacity. Ballooning dispersal in spiders can be considered as a passive dispersal process, in which dispersed distances depend on the prevalent wind velocity. We executed a reaction norm analysis to analyze how dispersal propensity of the salt marsh wolf spider Pardosa purbeckensis depended on population characteristics (patch size) and the environment (wind velocity). Dispersal propensity was affecte...

Science.gov (United States)

Incoming solar energy had to be assimilated to sustain it. .... Roll stability was achieved with an Earth sensor mounted on the directional antenna. .... Once more a rocket becomes the means of producing a vector change in velocity. ...

CERN Document Server

The delayed detonation model describes the observational properties of the majority of type Ia supernovae very well. Using numerical data from a three-dimensional deflagration model for type Ia supernovae, the intermittency of the turbulent velocity field and its implications on the probability of a deflagration-to-detonation (DDT) transition are investigated. From structure functions of the turbulent velocity fluctuations, we determine intermittency parameters based on the log-normal and the log-Poisson models. On the other hand, the analysis of the turbulent velocity fluctuations in the vicinity of the flame front by Roepke suggests a much higher probability of large velocity fluctuations on the grid scale in comparison to the log-normal intermittency model. Following Pan et al., we computed probability density functions for a DDT for the different distributions. Assuming that a DDT can occur in the ...

Science.gov (United States)

The ratio of particle velocity to translation speed exceeds 1 for 98% of .... The westward movement of the meandering jet and eddy system transports nutrient- rich ...... J. Hydrometeor., 4, 1044-1066. Gedney, N., P. M. Cox, H. Douville, ...