807 research outputs found
Design criteria for payload workstation accommodations
Anticipated shuttle sortie payload man-system design criteria needs are investigated. Man-system interactions for the scientific disciplines are listed and the extent is assessed to which documented Skylab experience is expected to provide system design guidance for each of the identified interactions. Where the analysis revealed that the reduced Skylab data does not answer the anticipated needs candidate criteria, based on unreduced Skylab data, available prior research, original analysis, or related requirements derived from previous space programs, are provided
Atmospheric measurements over kwajalein using falling spheres
Atmosphere measurements using falling spheres tracked by rada
Bostonia. Volume 6
Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs
Using airborne LiDAR Survey to explore historic-era archaeological landscapes of Montserrat in the eastern Caribbean
This article describes what appears to be the first archaeological application of airborne LiDAR survey to historic-era landscapes in the Caribbean archipelago, on the island of Montserrat. LiDAR is proving invaluable in extending the reach of traditional pedestrian survey into less favorable areas, such as those covered by dense neotropical forest and by ashfall from the past two decades of active eruptions by the Soufrière Hills volcano, and to sites in localities that are inaccessible on account of volcanic dangers. Emphasis is placed on two aspects of the research: first, the importance of ongoing, real-time interaction between the LiDAR analyst and the archaeological team in the field; and second, the advantages of exploiting the full potential of the three-dimensional LiDAR point cloud data for purposes of the visualization of archaeological sites and features
Islands on the line: Team report
This report brings together the ideas presented separately in the 5 reports of the Victoria University of Wellington Rural Socio-economic Survey of the Gilbert and Ellice (later Tuvalu) Islands
PSRs J0248+6021 and J2240+5832: Young Pulsars in the Northern Galactic Plane. Discovery, Timing, and Gamma-ray observations
Pulsars PSR J0248+6021 (rotation period P=217 ms and spin-down power Edot =
2.13E35 erg/s) and PSR J2240+5832 (P=140 ms, Edot = 2.12E35 erg/s) were
discovered in 1997 with the Nancay radio telescope during a northern Galactic
plane survey, using the Navy-Berkeley Pulsar Processor (NBPP) filter bank. GeV
gamma-ray pulsations from both were discovered using the Fermi Large Area
Telescope. Twelve years of radio and polarization data allow detailed
investigations. The two pulsars resemble each other both in radio and in
gamma-ray data. Both are rare in having a single gamma-ray pulse offset far
from the radio peak. The high dispersion measure for PSR J0248+6021 (DM = 370
pc cm^-3) is most likely due to its being within the dense, giant HII region W5
in the Perseus arm at a distance of 2 kpc, not beyond the edge of the Galaxy as
obtained from models of average electron distributions. Its high transverse
velocity and the low magnetic field along the line-of-sight favor this small
distance. Neither gamma-ray, X-ray, nor optical data yield evidence for a
pulsar wind nebula surrounding PSR J0248+6021. The gamma-ray luminosity for PSR
J0248+6021 is L_ gamma = (1.4 \pm 0.3)\times 10^34 erg/s. For PSR J2240+5832,
we find either L_gamma = (7.9 \pm 5.2) \times 10^34 erg/s if the pulsar is in
the Outer arm, or L_gamma = (2.2 \pm 1.7) \times 10^34 erg/s for the Perseus
arm. These luminosities are consistent with an L_gamma ~ sqrt(Edot) rule.
Comparison of the gamma-ray pulse profiles with model predictions, including
the constraints obtained from radio polarization data, favor emission in the
far magnetosphere. These two pulsars differ mainly in their inclination angles
and acceleration gap widths, which in turn explains the observed differences in
the gamma-ray peak widths.Comment: 13 pages, Accepted to Astronomy & Astrophysic
The medical student
The Medical Student was published from 1888-1921 by the students of Boston University School of Medicine
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