749 research outputs found
An IBM PC Data Base Design For Sao Paulo Air Pollution
A data base system for the Sao Paulo Air Pollution Network data was designed and implemented using an IBM TM Personal Computer. The data base was intended to be an image of the data produced by the network , keeping reliability in a small space due to diskette storage capacity. The whole system was implemented in Turbo Pascal(TM) using utility programs to support the data base. A magnetic tape containing a dump of the network data was used as a source of testing material for the data base. Three main programs were written that are used to convert Sao Paulo Network data files to the PC data base. These include real number conversions from the network host (PHILIPS PW 800[TM]) to IBM PC, validating, invalidating, changing values, and selecting pieces from data base to feed external software packages. The programs work in an interactive mode with the operator and reports are made for further follow-up. The program user guides are also described in this report.Master of Science in Public Healt
On the analysis of data emerging in non-linear and complex systemscomparison of two X-Ray prony spectra
New arguments proving that successive (repeated) measurements have a memory and actually remember each other are presented. The recognition of this peculiarity can change essentially the existing paradigm associated with conventional observation in behavior of different complex systems and lead towards the application of an intermediate model (IM). This IM can provide a very accurate fit of the measured data in terms of the Prony's decomposition. This decomposition, in turn, contains a small set of the fitting parameters relatively to the number of initial data points and allows comparing the measured data in cases where the âbest fitâ model based on some specific physical principles is absent. As an example, we consider two X-ray diffractometers (defined in paper as A- (âcheapâ) and B- (âexpensiveâ) that are used after their proper calibration for the measuring of the same substance (corundum a-Al2O3). The amplitude-frequency response (AFR) obtained in the frame of the Prony's decomposition can be used for comparison of the spectra recorded from (A) and (B) - X-ray diffractometers (XRDs) for calibration and other practical purposes. We prove also that the Fourier decomposition can be adapted to âidealâ experiment without memory while the Prony's decomposition corresponds to real measurement and can be fitted in the frame of the IM in this case. New statistical parameters describing the properties of experimental equipment (irrespective to their internal âfillingâ) are found. The suggested approach is rather general and can be used for calibration and comparison of different complex dynamical systems in practical purposes
Phosphorus removal by a fixed-bed hybrid polymer nanocomposite biofilm reactor
Eutrophication is one of the main challenges regarding the ecological quality of surface waters, phosphorus bioavailability being its main driver. In this context, a novel hybrid polymer nanocomposite (HPN-Pr) biofilm reactor aimed at integrated chemical phosphorus adsorption and biological removal was conceived. The assays pointed to removal of 1.2 mg P/g of reactive phosphorus and 1.01 mg P/g of total phosphorus under steady-state conditions. A mathematical adsorptionâbiological model was applied to predict reactor performance, which indicated that biological activity has a positive effect on reactor performance, increasing the amount of reactive phosphorus removed.The authors acknowledge the Portuguese Foundation for Science and Technology for the financial support under Project SFRH/BD/39085/2007
Transient Magnetic and Doppler Features Related to the White-light Flares in NOAA 10486
Rapidly moving transient features have been detected in magnetic and Doppler
images of super-active region NOAA 10486 during the X17/4B flare of 28 October
2003 and the X10/2B flare of 29 October 2003. Both these flares were extremely
energetic white-light events. The transient features appeared during impulsive
phases of the flares and moved with speeds ranging from 30 to 50 km s.
These features were located near the previously reported compact acoustic
\cite{Donea05} and seismic sources \cite{Zharkova07}. We examine the origin of
these features and their relationship with various aspects of the flares, {\it
viz.}, hard X-ray emission sources and flare kernels observed at different
layers - (i) photosphere (white-light continuum), (ii) chromosphere (H
6563\AA), (iii) temperature minimum region (UV 1600\AA), and (iv) transition
region (UV 284\AA).Comment: 26 pages, 13 figures, 2 tables, accepted for publication in Solar
Physic
Imaging Spectroscopy of a White-Light Solar Flare
We report observations of a white-light solar flare (SOL2010-06-12T00:57,
M2.0) observed by the Helioseismic Magnetic Imager (HMI) on the Solar Dynamics
Observatory (SDO) and the Reuven Ramaty High-Energy Solar Spectroscopic Imager
(RHESSI). The HMI data give us the first space-based high-resolution imaging
spectroscopy of a white-light flare, including continuum, Doppler, and magnetic
signatures for the photospheric FeI line at 6173.34{\AA} and its neighboring
continuum. In the impulsive phase of the flare, a bright white-light kernel
appears in each of the two magnetic footpoints. When the flare occurred, the
spectral coverage of the HMI filtergrams (six equidistant samples spanning
\pm172m{\AA} around nominal line center) encompassed the line core and the blue
continuum sufficiently far from the core to eliminate significant Doppler
crosstalk in the latter, which is otherwise a possibility for the extreme
conditions in a white-light flare. RHESSI obtained complete hard X-ray and
\Upsilon-ray spectra (this was the first \Upsilon-ray flare of Cycle 24). The
FeI line appears to be shifted to the blue during the flare but does not go
into emission; the contrast is nearly constant across the line profile. We did
not detect a seismic wave from this event. The HMI data suggest stepwise
changes of the line-of-sight magnetic field in the white-light footpoints.Comment: 14 pages, 7 figures, Accepted by Solar Physic
Extreme Ultra-Violet Spectroscopy of the Lower Solar Atmosphere During Solar Flares
The extreme ultraviolet portion of the solar spectrum contains a wealth of
diagnostic tools for probing the lower solar atmosphere in response to an
injection of energy, particularly during the impulsive phase of solar flares.
These include temperature and density sensitive line ratios, Doppler shifted
emission lines and nonthermal broadening, abundance measurements, differential
emission measure profiles, and continuum temperatures and energetics, among
others. In this paper I shall review some of the advances made in recent years
using these techniques, focusing primarily on studies that have utilized data
from Hinode/EIS and SDO/EVE, while also providing some historical background
and a summary of future spectroscopic instrumentation.Comment: 34 pages, 8 figures. Submitted to Solar Physics as part of the
Topical Issue on Solar and Stellar Flare
Non-linear QCD dynamics and exclusive production in collisions
The exclusive processes in electron-proton () interactions are an
important tool to investigate the QCD dynamics at high energies as they are in
general driven by the gluon content of proton which is strongly subject to
parton saturation effects. In this paper we compute the cross sections for the
exclusive vector meson production as well as the deeply virtual Compton
scattering (DVCS) relying on the color dipole approach and considering the
numerical solution of the Balitsky-Kovchegov equation including running
coupling corrections. We show that the small- evolution given by this
evolution equation is able to describe the DESY-HERA data and is relevant for
the physics of the exclusive observables in future electron-proton colliders
and in photoproduction processes to be measured in coherent interactions at the
LHC.Comment: 6 pages, 4 figure
Evidence for a mixed mass composition at the `ankle' in the cosmic-ray spectrum
We report a first measurement for ultra-high energy cosmic rays of the
correlation between the depth of shower maximum and the signal in the water
Cherenkov stations of air-showers registered simultaneously by the fluorescence
and the surface detectors of the Pierre Auger Observatory. Such a correlation
measurement is a unique feature of a hybrid air-shower observatory with
sensitivity to both the electromagnetic and muonic components. It allows an
accurate determination of the spread of primary masses in the cosmic-ray flux.
Up till now, constraints on the spread of primary masses have been dominated by
systematic uncertainties. The present correlation measurement is not affected
by systematics in the measurement of the depth of shower maximum or the signal
in the water Cherenkov stations. The analysis relies on general characteristics
of air showers and is thus robust also with respect to uncertainties in
hadronic event generators. The observed correlation in the energy range around
the `ankle' at differs significantly from
expectations for pure primary cosmic-ray compositions. A light composition made
up of proton and helium only is equally inconsistent with observations. The
data are explained well by a mixed composition including nuclei with mass . Scenarios such as the proton dip model, with almost pure compositions, are
thus disfavoured as the sole explanation of the ultrahigh-energy cosmic-ray
flux at Earth.Comment: Published version. Added journal reference and DOI. Added Report
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