3,690 research outputs found
Energetic solar particle fluxes out to 3 AU during the 7 May 1978 flare event
Simultaneous solar proton flux measurements on IMP 7 and by the world wide neutron monitor network during the May 7, 1978 flare event led to conclusions that in the energy range from 50 MeV to 10 GeV: (1) the propagation of the flare particles in the interplanetary magnetic field (IMF) between the Sun and the Earth was nearly scatter free; and (2) therefore, the intensity time (IT) profiles of the solar proton fluxes observed at Earth for about one hour after onset represent the solar injection profiles even to energies as low as 50 MeV. Observations of the IMF at Helios A indicate that the IMF was undisturbed between the Sun and Helios A at the time of the May 7, 1978 flare event; and, therefore, the solar particle propagation was also scatter free from the Sun to Helios A
Evaluation of S190A radiometric exposure test data
The S190A preflight radiometric exposure test data generated as part of preflight and system test of KM-002 Sequence 29 on flight camera S/N 002 was analyzed. The analysis was to determine camera system transmission using available data which included: (1) films exposed to a calibrated light source subject; (2) filter transmission data; (3) calibrated light source data; (4) density vs. log10 exposure curves for the films; and (5) spectral sensitometric data for the films. The procedure used is outlined, and includes the data and a transmission matrix as a function of field position for nine measured points on each station-film-filter-aperture-shutter speed combination
Some characteristics of the solar flare event of February 16, 1984
In the morning of February 16, 1984 a solar cosmic ray event (GLE) was recorded by the world wide network of neutron monitors (NM). The counting rate vs. time profile of the Goose Bay NM (geog. lat. = 53.3 deg. N, deog. long. = 299.6 deg E) where the increase is expressed as percent of the counting rate of an equatorial sea level NM is presented. The Goose Bay NM was observed to have the maximum response to the solar particles. Its counting rate vs. time profile exhibits a rapid increase to maximum, has a large amplitude (approx. 170%) and decays rapidly to background in approx. 90 min. In Fig. 1 we also show the counting rate vs. time profile for the Tixie Bay NM (71.6 deg, 128.9 deg) which recorded an increase of only a few percent. Since the NMs at Goose Bay and Tixie Bay have asymptotic viewing directions approx. 180 deg apart in longitude, the anisotropy of the solar particle flux at Earth from these stations
Power law creep and delayed failure of gels and fibrous materials under stress
Motivated by recent experiments studying the creep and breakup of a protein
gel under stress, we introduce a simple mesoscopic model for the irreversible
failure of gels and fibrous materials, and demonstrate it to capture much of
the phenomenology seen experimentally. This includes a primary creep regime in
which the shear rate decreases as a power law over several decades of time, a
secondary crossover regime in which the shear rate attains a minimum, and a
tertiary regime in which the shear rate increases dramatically up to a finite
time singularity, signifying irreversible material failure. The model also
captures a linear Monkman-Grant scaling of the failure time with the earlier
time at which the shear rate attained its minimum, and a Basquin-like power law
scaling of the failure time with imposed stress, as seen experimentally. The
model furthermore predicts a slow accumulation of low levels of material damage
during primary creep, followed by the growth of fractures leading to sudden
material failure, as seen experimentally.Comment: 4 pages, 5 figures. Accepted for publication, Soft Matte
Power law creep and delayed failure of gels and fibrous materials under stress
Motivated by recent experiments studying the creep and breakup of a protein gel under stress, we introduce a simple mesoscopic model for the irreversible failure of gels and fibrous materials, and demonstrate it to capture much of the phenomenology seen experimentally. This includes a primary creep regime in which the shear rate decreases as a power law over several decades of time, a secondary crossover regime in which the shear rate attains a minimum, and a tertiary regime in which the shear rate increases dramatically up to a finite time singularity, signifying irreversible material failure. The model also captures a linear Monkman–Grant scaling of the failure time with the earlier time at which the shear rate attained its minimum, and a Basquin-like power law scaling of the failure time with imposed stress, as seen experimentally. The model furthermore predicts a slow accumulation of low levels of material damage during primary creep, followed by the growth of fractures leading to sudden material failure, as seen experimentally
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The development of a space climatology: 1. solar-wind magnetosphere coupling as a function of timescale and the effect of data gaps
Different terrestrial space weather indicators (such as geomagnetic indices, transpolar voltage, and ring current particle content) depend on different “coupling functions” (combinations of near-Earth solar wind parameters) and previous studies also reported a dependence on the averaging timescale, {\tau}. We study the relationships of the am and SME geomagnetic indices to the power input into the magnetosphere P_{\alpha}, estimated using the optimum coupling exponent {\alpha} for a range of {\tau} between 1 min and 1 year. The effect of missing data is investigated by introducing synthetic gaps into near-continuous data and the best method for dealing with them when deriving the coupling function, is formally defined. Using P_{\alpha}, we show that gaps in data recorded before 1995 have introduced considerable errors into coupling functions. From the near-continuous solar wind data for 1996-2016, we find {\alpha} = 0.44 plus/minus 0.02 and no significant evidence that {\alpha} depends on {\tau}, yielding P_{\alpha} = B^0.88 Vsw^1.90 (mswNsw)^0.23 sin4({\theta}/2), where B is the Interplanetary Magnetic Field (IMF), Nsw the solar wind number density, msw its mean ion mass, Vsw its velocity and {\theta} is the IMF clock angle in the Geocentric Solar Magnetospheric reference frame. Values of P_{\alpha} that are accurate to within plus/minus 5% for 1996-2016 have an availability of 83.8% and the correlation between P_{\alpha} and am for these data is shown to be 0.990 (between 0.972 and 0.997 at the 2{\sigma} uncertainty level), 0.897 plus/minus 0.004, and 0.790 plus/minus 0.03, for {\tau} of 1 year, 1 day and 3 hours, respectively, and that between P_{alpha} and SME at {\tau} of 1 min. is 0.7046 plus/minus 0.0004
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Variability of dayside convection and motions of the cusp/cleft aurora
We present measurements of the ionospheric plasma flow over the range of invariant latitudes 71–76°, observed at 10-second resolution using both the EISCAT radars, with simultaneous observations of the 630 nm cusp/cleft aurora made by a meridian-scanning photometer at Ny Ålesund, Svalbard. A major increase in the trans-auroral voltage from 5 to 40 kV (associated with sunward convection in the early afternoon sector) is found to follow a southward motion of the aurora and coincide with the onset of regular transient auroral breakup events. It is shown that these observations are consistent with recent theoretical work on how ionospheric flows are excited by time-dependent reconnection at the dayside magnetopause
Reality in quantum mechanics, Extended Everett Concept, and consciousness
Conceptual problems in quantum mechanics result from the specific quantum
concept of reality and require, for their solution, including the observer's
consciousness into quantum theory of measurements. Most naturally this is
achieved in the framework of Everett's "many-worlds interpretation" of quantum
mechanics. According to this interpretation, various classical alternatives are
perceived by consciousness separately from each other. In the Extended Everett
Concept (EEC) proposed by the present author, the separation of the
alternatives is identified with the phenomenon of consciousness. This explains
classical character of the alternatives and unusual manifestations of
consciousness arising "at the edge of consciousness" (i.e. in sleep or trance)
when its access to "other alternative classical realities" (other Everett's
worlds) becomes feasible. Because of reversibility of quantum evolution in EEC,
all time moments in the quantum world are equivalent while the impression of
flow of time appears only in consciousness. If it is assumed that consciousness
may influence onto probabilities of alternatives (which is consistent in case
of infinitely many Everett's worlds), EEC explains free will, "probabilistic
miracles" (observing low-probability events) and decreasing entropy in the
sphere of life.Comment: 17 pages, 2 figures in EP
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