29,139 research outputs found
Central Asia Wars and Ethnic Conflicts – Rebuilding Failed States
human development, culture
Satellite applications to electric-utility communications needs
Significant changes in the Nation's electric power systems are expected to result from the integration of new technology, possible during the next decade. Digital communications for monitor and control, exclusive of protective relaying, are expected to double or triple current traffic. A nationwide estimate of 13 Mb/s traffic is projected. Of this total, 8 Mb/s is attributed to the bulk-power system as it is now being operated (4 Mb/s). This traffic could be accommodated by current communications satellites using 3- to 4.5-m-diameter ground terminals costing 70,000 each. The remaining 5-Mb/s traffic is attributed to new technology concepts integrated into the distribution system. Such traffic is not compatible with current satellite technology because it requires small, low-cost ground terminals. Therefore, a high effective isotropic radiated power satellite, such as the one being planned by NASA for the Land Mobile Satellite Service, is required
Squarks in Tevatron Dilepton Events ?
We consider unusual events in the CDF and D0 dilepton+jets sample with very
high ET(lepton) and ET(missing). It is possible, but very unlikely, that these
events originate from top quark pair production; however, they have
characteristics that are better accounted for by decays of supersymmetric
quarks with mass in the region of 300 GeV.Comment: 5 pages, 2 postscript (eps) figures, uses sprocl.sty (included
Classifying vortices in S= 3 Bose-Einstein condensates
Motivated by the recent realization of a Cr Bose-Einstein condensate,
we consider the phase diagram of a general spin-three condensate as a function
of its scattering lengths. We classify each phase according to its ``reciprocal
spinor,'' using a method developed in a previous work. We show that such a
classification can be naturally extended to describe the vortices for a spinor
condensate by using the topological theory of defects. To illustrate, we
systematically describe the types of vortex excitations for each phase of the
spin-three condensate
Analysis of changes in leg volume parameters, and orthostatic tolerance in response to lower body negative pressure during 59 days exposure to zero gravity Skylab 3
The cardiovascular responses of the Apollo crewmen associated with postflight evaluations indicate varying decrements of orthostatic tolerance. The postflight changes indicate a slightly diminished ability to the cardiovascular system to function effectively against gravity following exposure to weightlessness. The objective of the Skylab LBNP experiments (M092) was to provide information about the magnitude and time course of the cardiovascular changes associated with prolonged periods of exposure to weightlessness. This report details the equipment, signal processing and analysis of the leg volume data obtained from the M092 experiment of the Skylab 3 Mission
Incorporation of the statistical uncertainty in the background estimate into the upper limit on the signal
We present a procedure for calculating an upper limit on the number of signal
events which incorporates the Poisson uncertainty in the background, estimated
from control regions of one or two dimensions. For small number of signal
events, the upper limit obtained is more stringent than that extracted without
including the Poisson uncertainty. This trend continues until the number of
background events is comparable with the signal. When the number of background
events is comparable or larger than the signal, the upper limit obtained is
less stringent than that extracted without including the Poisson uncertainty.
It is therefore important to incorporate the Poisson uncertainty into the upper
limit; otherwise the upper limit obtained could be too stringent.Comment: 14 pages, 4 figure
High performance structures
Materials selection, structural geometry, proof testing and statistical screening, prestressing, and system energy as tools for designing optimum trusses and other high performance structure
- …