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Normative Values for 18-30 Ages of Benton Visual Retention Test Correct Scores and Intelligence Quotients: A Short Report for Clinical Comparison
The Benton Visual Retention Test (BVRT) is a well known test used to assess visual memory deficits and visual spatial abilities in patients. There is normative data available for the 18-30 age range though it is not comprehensive and does not cover the higher intelligence quotient ranges. Findings from two studies are presented in combination for use as normative correct score values
Advanced propulsion for LEO-Moon transport. 2: Tether configurations in the LEO-Moon system
This brief work discusses a possible application of a tether as a dynamical element in a low Earth orbit (LEO)-Moon transport system, and is a part of the Cal Space study of that transport system. To be specific, that study concentrated on the downward transport of O2 from the Moon to LEO, where it is stored for use as a rocket propellant, thus reducing Earth liftoff mass requirements by a factor of about 8. Moreover, in order to display clearly the role of advanced technology, only one novel technology was introduced at a single node in the transport system, the rest being 'conventional' rocket transport. Tethers were found useful in several different roles: hanging from platforms in lunar orbits, as supports for elevators, spinning in LEO, or spinning in a tether transport orbit, an elliptical orbit with perigee at approximately 600 km. This last use is considered here. Presented are the usefulness of the tether, nature of the tether system, the apparatus needed to support, deploy, and control it, and a discussion of needed developments
The Clusters AgeS Experiment (CASE). III. Analysis of the Eccentric Eclipsing Binary V32 in the Globular Cluster NGC 6397
We present spectroscopic and photometric observations of the eclipsing binary
V32 located in the central field of the globular cluster NGC 6397. The variable
is a single-line spectroscopic binary with an orbital period of 9.8783d and a
large eccentricity of e=0.32. Its systemic velocity (gamma=20.7 km/s) and
metallicity ([Fe/H] -1.9) are both consistent with cluster membership. The
primary component of the binary is located at the top of the main-sequence
turn-off on the cluster color-magnitude diagram. Only a shallow primary eclipse
is observed in the light curve. Based on stellar models for an age of 12Gyr and
the mass-function derived from the radial velocity curve, we estimate the
masses to be M_p=0.79 Msun and M_s=0.23 Msun. The light curve of V32 can be
reproduced by adopting R_p=1.569 Rsun and R_s=0.236 Rsun for the radii and
i=85.44 deg for the system inclination. The system geometry precludes
observations of the secondary eclipse. The large eccentricity of the orbit is
puzzling given that for metal poor, halo binaries the transition from circular
to eccentric orbit occurs at an orbital period of about 20 days. We suppose
that the orbit of V32 was modified relatively recently by dynamical interaction
with other cluster star(s).An alternative explanation of the observed
eccentricity calls for the presence of a third body in the system.Comment: AJ, accepte
Velocimetry with refractive index matching for complex flow configurations, phase 1
The feasibility of obtaining detailed velocity field measurements in large Reynolds number flow of the Space Shuttle Main Engine (SSME) main injector bowl was demonstrated using laser velocimetry and the developed refractive-index-matching technique. An experimental system to provide appropriate flow rates and temperature control of refractive-index-matching fluid was designed and tested. Test results are presented to establish the feasibility of obtaining accurate velocity measurements that map the entire field including the flow through the LOX post bundles: sample mean velocity, turbulence intensity, and spectral results are presented. The results indicate that a suitable fluid and control system is feasible for the representation of complex rocket-engine configurations and that measurements of velocity characteristics can be obtained without the optical access restrictions normally associated with laser velocimetry. The refractive-index-matching technique considered needs to be further developed and extended to represent other rocket-engine flows where current methods either cannot measure with adequate accuracy or they fail
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