15,262 research outputs found
TCB operation supply inventory system /TCBSYS/
System produces inventory report for each updated period and special report for long term inventory information summary. Report summarizes consumption, outstanding orders, and balance of each inventory item. System generates, corrects, and adjusts inventory tapes. Restrictions of system are listed
Radiance and Doppler shift distributions across the network of the quiet Sun
The radiance and Doppler-shift distributions across the solar network provide
observational constraints of two-dimensional modeling of transition-region
emission and flows in coronal funnels. Two different methods, dispersion plots
and average-profile studies, were applied to investigate these distributions.
In the dispersion plots, we divided the entire scanned region into a bright and
a dark part according to an image of Fe xii; we plotted intensities and Doppler
shifts in each bin as determined according to a filtered intensity of Si ii. We
also studied the difference in height variations of the magnetic field as
extrapolated from the MDI magnetogram, in and outside network. For the
average-profile study, we selected 74 individual cases and derived the average
profiles of intensities and Doppler shifts across the network. The dispersion
plots reveal that the intensities of Si ii and C iv increase from network
boundary to network center in both parts. However, the intensity of Ne viii
shows different trends, namely increasing in the bright part and decreasing in
the dark part. In both parts, the Doppler shift of C iv increases steadily from
internetwork to network center. The average-profile study reveals that the
intensities of the three lines all decline from the network center to
internetwork region. The binned intensities of Si ii and Ne viii have a good
correlation. We also find that the large blue shift of Ne viii does not
coincide with large red shift of C iv. Our results suggest that the network
structure is still prominent at the layer where Ne viii is formed in the quiet
Sun, and that the magnetic structures expand more strongly in the dark part
than in the bright part of this quiet Sun region.Comment: 10 pages,9 figure
Observation of indirect ionization of W7+ in an electron-beam ion-trap plasma
In this work, visible and extreme ultraviolet spectra of W7+ are measured
using the high-temperature superconducting electron-beam ion trap (EBIT) at the
Shanghai EBIT Laboratory under extremely low-energy conditions (lower than the
nominal electron-beam energy of 130 eV). The relevant atomic structure is
calculated using the flexible atomic code package based on the relativistic
configuration interaction method. The GRASP2K code, in the framework of the
multiconfiguration Dirac-Hartree-Fock method, is employed as well for
calculating the wavelength of the M1 transition in the ground configuration of
W7+. A line from the W7+ ions is observed at a little higher electron-beam
energy than the ionization potential for W4+, making this line appear to be
from W5+. A hypothesis for the charge-state evolution of W7+ is proposed based
on our experimental and theoretical results; that is, the occurrence of W7+
ions results from indirect ionization caused by stepwise excitation between
some metastable states of lower-charge-state W ions, at the nominal
electron-beam energy of 59 eV
Upflows in the upper transition region of the quiet Sun
We investigate the physical meaning of the prominent blue shifts of Ne VIII,
which is observed to be associated with quiet-Sun network junctions (boundary
intersections), through data analyses combining force-free-field extrapolations
with EUV spectroscopic observations. For a middle-latitude region, we
reconstruct the magnetic funnel structure in a sub-region showing faint
emission in EIT-Fe 195. This funnel appears to consist of several smaller
funnels that originate from network lanes, expand with height and finally merge
into a single wide open-field region. However, the large blue shifts of Ne VIII
are generally not associated with open fields, but seem to be associated with
the legs of closed magnetic loops. Moreover, in most cases significant upflows
are found in both of the funnel-shaped loop legs. These quasi-steady upflows
are regarded as signatures of mass supply to the coronal loops rather than the
solar wind. Our observational result also reveals that in many cases the
upflows in the upper transition region (TR) and the downflows in the middle TR
are not fully cospatial. Based on these new observational results, we suggest
different TR structures in coronal holes and in the quiet Sun.Comment: 4 pages, 4 figures, will appear in the Proceedings of the Solar wind
12 conferenc
From the Complete Yang Model to Snyder's Model, de Sitter Special Relativity and Their Duality
By means of Dirac procedure, we re-examine Yang's quantized space-time model,
its relation to Snyder's model, the de Sitter special relativity and their
UV-IR duality. Starting from a dimensionless dS_5-space in a 5+1-d Mink-space a
complete Yang model at both classical and quantum level can be presented and
there really exist Snyder's model, the dS special relativity and the duality.Comment: 7 papge
Projection in snowfall characteristics over the European Alps and its sensitivity to the SST changes: results from a 50 km resolution AGCM
The end-of-century projection of the snowfall characteristics over the Alps region is studied using the 50-km resolution atmospheric global climate model, HiRAM (high-resolution atmospheric model). The model is forced by three different patterns of projections in the sea surface temperature (SST) in order to assess the sensitivity of snowfall characteristics to theses patterns. It is found that the mean snowfall intensity and frequency is poorly affected by the differences in SST forcing. However, the projections of heavy snowfall events strongly depend on the SST scenario. The changes in temperature and frequency of precipitation and freezing days over the Alps were investigated. We found that these variables did not exhibit a clear dependence to the SST scenario and could not explain the differences observed in snowfall projections. Changes in the moisture transport from the Atlantic Ocean to Europe were found significantly different between each scenario and are assumed to be the main factor affecting the projections of snowfalls, by providing more or less moisture supply
Transient quantum transport in double-dot Aharonov-Bohm interferometers
Real-time nonequilibrium quantum dynamics of electrons in double-dot
Aharonov-Bohm (AB) interferometers is studied using an exact solution of the
master equation. The building of the coherence between the two electronic paths
shows up via the time-dependent amplitude of the AB oscillations in the
transient transport current, and can be enhanced by varying the applied bias on
the leads, the on-site energy difference between the dots and the asymmetry of
the coupling of the dots to the leads. The transient oscillations of the
transport current do not obey phase rigidity. The circulating current has an
anti-symmetric AB oscillation in the flux. The non-degeneracy of the on-site
energies and the finite bias cause the occupation in each dot to have an
arbitrary flux dependence as the coupling asymmetry is varied.Comment: 11 pages, 5 figure
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