Computer Sciences Corporation

About: Computer Sciences Corporation is a based out in . It is known for research contribution in the topics: Spacecraft & Software development. The organization has 1916 authors who have published 2389 publications receiving 62729 citations. The organization is also known as: CSC.

Solar radius change between 1925 and 1979

Abstract: From an analysis of numerous reports from different locations on the duration of totality of the solar eclipses on January 24, 1925, and February 26, 1979, it is found that the solar radius at the earlier date was 0.5 arcsec (or 375 km) larger than at the later date. The correction to the standard solar radius found for each eclipse is different when different subsets of the observations are used (for example, edge of path of totality timings compared with central timings). This is seen as suggesting the existence of systematic inaccuracies in our knowledge of the lunar figure. The differences between the corrections for both eclipses, however, are very similar for all subsets considered, indicating that changes of the solar size may be reliably inferred despite the existence of the lunar figure errors so long as there is proper consideration of the distribution of the observations. These results are regarded as strong evidence in support of the occurrence of solar radius changes on shorter than evolutionary time scales.

Motions of charged particles in the magnetosphere under the influence of a time-varying large scale convection electric field

Abstract: The motions of charged particles under the influence of the geomagnetic and electric fields are quite complex in the region of the inner magnetosphere. The Volland-Stern type large-scale convection electric field with gamma = 2 has been used successfully to predict both the plasmapause location and particle enhancements determined from Explorer 45 (S3-A) measurements. Recently introduced into the trajectory calculations of Ejiri et al. (1978) is a time dependence in this electric field based on the variation in Kp for actual magnetic storm conditions. The particle trajectories are computed as they change in this time-varying electric field. Several storm fronts of particles of different magnetic moments are allowed to be injected into the inner magnetosphere from L = 10 in the equatorial plane. The motions of these fronts are presented in a movie format. The local time of injection, the particle magnetic moments and the subsequent temporal history of the magnetospheric electric field play important roles in determining whether the injected particles are trapped within the ring current region or whether they are convected to regions outside the inner magnetosphere.

The apogee spectroscopic survey of kepler planet hosts: feasibility, efficiency, and first results

Abstract: The Kepler mission has yielded a large number of planet candidates from among the Kepler Objects of Interest(KOIs), but spectroscopic follow-up of these relatively faint stars is a serious bottleneck in confirming and characterizing these systems. We present motivation and survey design for an ongoing project with the Sloan Digital Sky Survey III multiplexed Apache Point Observatory Galactic Evolution Experiment (APOGEE) near-infrared spectrograph to monitor hundreds of KOI host stars. We report some of our first results using representative targets from our sample, which include current planet candidates that we find to be false positives, as well as candidates listed as false positives that we do not find to be spectroscopic binaries. With this survey, KOI hosts are observed over ∼20 epochs at a radial velocity (RV) precision of 100–200ms−1. These observations can easily identify a majority of false positives caused by physically associated stellar or substellar binaries, and in many cases, fully characterize their orbits. We demonstrate that APOGEE is capable of achieving RV precision at the 100–200ms−1 level over long time baselines, and that APOGEE’s multiplexing capability makes it substantially more efficient at identifying false positives due to binaries than other single-object spectrographs working to confirm KOIs as planets. These APOGEE RVs enable ancillary science projects, such as studies of fundamental stellar astrophysics or intrinsically rare substellar companions. The coadded APOGEE spectra can be used to derive stellar properties (Teff, log g) and chemical abundances of over a dozen elements to probe correlations of planet properties with individual elemental abundances.

Graphical input display in an insurance processing system

Abstract: A graphical display in an insurance processing system is disclosed. The graphical display may include a representation of a human body. The representation of the human body may provide information to a user that is helpful in specifying insurance claim information. For example, the representation may provide information regarding body parts, information regarding injury codes, information regarding common injuries, information regarding common treatments and/or information regarding treatment codes. The representation may also be used to provide input into the insurance processing system.

Comparing the Log-Normal and Gamma-Gamma model to experimental probability density functions of aperture averaging data

Abstract: Irradiance data were collected over a 1km horizontal terrestrial path using several different sized receiving apertures. The data were collected under moderate-to-strong turbulen ce conditions. The receiver sy stem consisted of a 154mm (6”) refracting telescope outfitted with several removable apertures. The path was instrumented with three 3-axis anemometers and three scintillometers, two of which were capable of measuring the inner scale of turbulence in addition to C n2 . Histograms were formed with th e data and compared to the Log-Normal and Gamma-Gamma PDF models. As expected, neither PDF model was applicable under all conditions of aperture averaging. Hypotheses are made as to why the models were unable to completely capture the eff ects of aperture averaging on received irradiance data. Keywords: aperture averaging, scintillation, free space optics, optical communications, PDF, probability density, speckle, irradiance fluctuations 1. INTRODUCTION The dominant noise source in an FSO communication system is atmosphere-induced intensity and phase fluctuations; scintillation. A larger aperture (collecting lens) can help reduce scintillation effects and improve SNR. Design criteria such as detector threshold level, probability of detection, mean fade time, number of fades, and SNR require knowledge of the probability density f unction (PDF) of the received ir radiance of the optical field. The PDF of the received irradiance is nonstationary by nature and is dependent upon the atmospheric turbulence parameters, transmitted beam characteristics, and receiver design parame ters; such as aperture size and bandwidt h. Nonetheless, an accurate PDF of the received irradiance is necessary to build a robust and reliable FSOC. Early studies in irradiance statistics focuse d on single family distributions, such as the modified Rician and Log-Normal distribution