15,097 research outputs found
PriPeARL: A Framework for Privacy-Preserving Analytics and Reporting at LinkedIn
Preserving privacy of users is a key requirement of web-scale analytics and
reporting applications, and has witnessed a renewed focus in light of recent
data breaches and new regulations such as GDPR. We focus on the problem of
computing robust, reliable analytics in a privacy-preserving manner, while
satisfying product requirements. We present PriPeARL, a framework for
privacy-preserving analytics and reporting, inspired by differential privacy.
We describe the overall design and architecture, and the key modeling
components, focusing on the unique challenges associated with privacy,
coverage, utility, and consistency. We perform an experimental study in the
context of ads analytics and reporting at LinkedIn, thereby demonstrating the
tradeoffs between privacy and utility needs, and the applicability of
privacy-preserving mechanisms to real-world data. We also highlight the lessons
learned from the production deployment of our system at LinkedIn.Comment: Conference information: ACM International Conference on Information
and Knowledge Management (CIKM 2018
Radiative rates and electron impact excitation rates for transitions in He II
We report calculations of energy levels, radiative rates, collision
strengths, and effective collision strengths for transitions among the lowest
25 levels of the n <= 5 configurations of He~II. The general-purpose
relativistic atomic structure package (GRASP) and Dirac atomic R-matrix code
(DARC) are adopted for the calculations. Radiative rates, oscillator strengths,
and line strengths are reported for all electric dipole (E1), magnetic dipole
(M1), electric quadrupole (E2), and magnetic quadrupole (M2) transitions among
the 25 levels. Furthermore, collision strengths and effective collision
strengths are listed for all 300 transitions among the above 25 levels over a
wide energy (temperature) range up to 9 Ryd (10**5.4 K). Comparisons are made
with earlier available results and the accuracy of the data is assessed.Comment: 30 pages of text including 12 figures and 5 Tables will appear in
ATOMS 5 (2017
Event-by-Event Search for Charged Neutral Fluctuations in Pb - Pb Collisions at 158-A-GeV
Results from the analysis of data obtained from the WA98 experiment at the
CERN SPS have been presented. Some events have been filtered which show photon
excess in limited zones within the overlap region of the charged
particle and photon multiplicity detectors.Comment: 6 pages, 4 figure
Annealing of defects in Fe after MeV Heavy ion irradiation
We report study of recovery dynamics, followed by in-situ resistivity
measurement after 100 MeV oxygen ion irradiation, in cold rolled Fe at 300K.
Scaling behavior with microstructural density and temperature of sample have
been used to establish stress induced defects formed during irradiation as a
new type of sink. The dynamics after irradiation has been shown to be due to
migration of defects to two types of sinks i.e. stress induced defect as
variable sinks and internal surfaces as fixed sinks. Experimental data obtained
under various experimental conditions have been fitted to theoretical curves.
Parameters thus obtained from fitting are employed to establish effect of
electronic energy loss and temperature on recovery dynamics and stress
associated with variable sinks.Comment: 12 pages, 7 figures. Europhysics Letter (in press
Studies in matter antimatter separation and in the origin of lunar magnetism
A progress report, covering lunar and planetary research is introduced. Data cover lunar ionospheric models, lunar and planetary geology, and lunar magnetism. Wind tunnel simulations of Mars aeolian problems and a comparative study of basaltic analogs of Lunar and Martial volcanic features was discussed
Ultraviolet emission lines of Si II in quasars --- investigating the "Si II disaster"
The observed line intensity ratios of the Si II 1263 and 1307 \AA\ multiplets
to that of Si II 1814\,\AA\ in the broad line region of quasars are both an
order of magnitude larger than the theoretical values. This was first pointed
out by Baldwin et al. (1996), who termed it the "Si II disaster", and it has
remained unresolved. We investigate the problem in the light of newly-published
atomic data for Si II. Specifically, we perform broad line region calculations
using several different atomic datasets within the CLOUDY modeling code under
optically thick quasar cloud conditions. In addition, we test for selective
pumping by the source photons or intrinsic galactic reddening as possible
causes for the discrepancy, and also consider blending with other species.
However, we find that none of the options investigated resolves the Si II
disaster, with the potential exception of microturbulent velocity broadening
and line blending. We find that a larger microturbulent velocity () may solve the Si II disaster through continuum pumping and other
effects. The CLOUDY models indicate strong blending of the Si II 1307 \AA\
multiplet with emission lines of O I, although the predicted degree of blending
is incompatible with the observed 1263/1307 intensity ratios. Clearly, more
work is required on the quasar modelling of not just the Si II lines but also
nearby transitions (in particular those of O I) to fully investigate if
blending may be responsible for the Si II disaster.Comment: Accepted for publication in Ap
An investigation of Fe XV emission lines in solar flare spectra
Previously, large discrepancies have been found between theory and
observation for Fe XV emission line ratios in solar flare spectra covering the
224-327 A wavelength range, obtained by the Naval Research Laboratory's S082A
instrument on board Skylab. These discrepancies have been attributed to either
errors in the adopted atomic data or the presence of additional atomic
processes not included in the modelling, such as fluorescence. However our
analysis of these plus other S082A flare observations (the latter containing Fe
XV transitions between 321-482 A), performed using the most recent Fe XV atomic
physics calculations in conjunction with a CHIANTI synthetic flare spectrum,
indicate that blending of the lines is primarily responsible for the
discrepancies. As a result, most Fe XV lines cannot be employed as electron
density diagnostics for solar flares, at least at the spectral resolution of
S082A and similar instruments (i.e. ~ 0.1 A). An exception is the intensity
ratio I(321.8 A)/I(327.0 A), which appears to provide good estimates of the
electron density at this spectral resolution.Comment: 6 pages, 3 figures, Astronomy & Astrophysics, in pres
Quantification of yield gaps in rain-fed rice, wheat, cotton and mustard in India
Rainfed farming / Crop yield / Simulation / Rice / Wheat / Cotton / Mustard / India
Electron Impact Excitation Cross Sections for Hydrogen-Like Ions
We present cross sections for electron-impact-induced transitions n --> n' in
hydrogen-like ions C 5+, Ne 9+, Al 12+, and Ar 17+. The cross sections are
computed by Coulomb-Born with exchange and normalization (CBE) method for all
transitions with n < n' < 7 and by convergent close-coupling (CCC) method for
transitions with n 2s and 1s
--> 2p are presented as well. The CCC and CBE cross sections agree to better
than 10% with each other and with earlier close-coupling results (available for
transition 1 --> 2 only). Analytical expression for n --> n' cross sections and
semiempirical formulae are discussed.Comment: RevTeX, 5 pages, 13 PostScript figures, submitted to Phys. Rev.
Малая автоматизация на ЦВМ "Урал-11Б"
Wireless communication technologies like GPRS, UMTS and WLAN, combined with the availability of high-end, affordable mobile devices enable the development of the advanced and innovative mobile services. Devices such as mobile phones and Personal Digital Assistants let the users access a wide range of new offerings whenever and wherever they happen to be. A strategic approach for the quality assurance of these mobile data services should take into account a number of characteristics unique to the mobile paradigm, the increased complexity of emerging handheld devices, the greater sensitivity to security and load related problems in wireless infrastructure and increased complexities of scale. This paper identifies the major factors influencing the development and testing strategies for these applications and accordingly elaborates effective quality assurance principles to ensure productive and scalable mobile data services
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