43 research outputs found
Securing Heterogeneous Privacy Protection in Social Network Records based Encryption Scheme
This survey places of interest the major issues concerning privacy and security in online social networks. Firstly, we discuss investigate that aims to protect user data from the an assortment of attack vantage points together with other users, advertisers, third party request developers, and the online social arrangement provider itself. Next we cover social network supposition of user attributes, locate hubs, and link prediction. Because online social networks are so saturated with sensitive information, network inference plays a major privacy role. Social Networking sites go upwards since of all these reasons. In recent years indicates that for many people they are now the mainstream communication knowledge. Social networking sites come under few of the most frequently browsed categories websites in the world. Nevertheless Social Networking sites are also vulnerable to various problems threats and attacks such as revelation of information, identity thefts etc. Privacy practice in social networking sites often appear convoluted as in sequence sharing stands in discord with the need to reduce disclosure-related abuses. Facebook is one such most popular and widely used Social Networking sites which have its own healthy set of Privacy policy
The Performance of the Robo-AO Laser Guide Star Adaptive Optics System at the Kitt Peak 2.1-m Telescope
Robo-AO is an autonomous laser guide star adaptive optics system recently
commissioned at the Kitt Peak 2.1-m telescope. Now operating every clear night,
Robo-AO at the 2.1-m telescope is the first dedicated adaptive optics
observatory. This paper presents the imaging performance of the adaptive optics
system in its first eighteen months of operations. For a median seeing value of
, the average Strehl ratio is 4\% in the band
and 29\% in the J band. After post-processing, the contrast ratio under
sub-arcsecond seeing for a primary star is five and
seven magnitudes at radial offsets of and
, respectively. The data processing and archiving pipelines
run automatically at the end of each night. The first stage of the processing
pipeline shifts and adds the data using techniques alternately optimized for
stars with high and low SNRs. The second "high contrast" stage of the pipeline
is eponymously well suited to finding faint stellar companions.Comment: 12 pages, 16 figures, to be submitted to PAS
The Performance of the Robo-AO Laser Guide Star Adaptive Optics System at the Kitt Peak 2.1 m Telescope
Multi-wavelength observations of afterglow of GRB 080319B and the modeling constraints
We present observations of the afterglow of GRB 080319B at optical, mm and
radio frequencies from a few hours to 67 days after the burst. Present
observations along with other published multi-wavelength data have been used to
study the light-curves and spectral energy distributions of the burst
afterglow. The nature of this brightest cosmic explosion has been explored
based on the observed properties and it's comparison with the afterglow models.
Our results show that the observed features of the afterglow fits equally good
with the Inter Stellar Matter and the Stellar Wind density profiles of the
circum-burst medium. In case of both density profiles, location of the maximum
synchrotron frequency is below optical and the value of cooling break
frequency is below rays, s after the burst. Also, the
derived value of the Lorentz factor at the time of naked eye brightness is
with the corresponding blast wave size of cm. The
numerical fit to the multi-wavelength afterglow data constraints the values of
physical parameters and the emission mechanism of the burst.Comment: 8 Pages, 3 Figures, Accepted for publication to Astronomy and
Astrophysics on 02/04/200
Community Inquiry Labs as Effective Community Informatics Tools
Meeting these challenges is crucial as we work to address community
aspirations, capabilities, and problems. We are contributing to this effort
through our current research and development on Community Inquiry Labs
(CILs). A CIL is most importantly a concept, although we are developing webbased
tools that are freely available to anyone wishing to support community
inquiry online (http://inquiry.uiuc.edu/cil). Our ultimate aim is to empower
communities by supporting the development of the next generation of
creative ICT ideas, people, tools, and designs.unpublishedis peer reviewe