58,945 research outputs found
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Speaking of Evidence: An Empirical Study of the Reporting of Forensic Conclusions in US Criminal Trials
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Rethinking privacy in social networks: A case study of beacon
Popular online social network sites (SNS) such as Facebook and Bebo are technological platforms that are posing questions about personal privacy. This paper contributes to our understanding of the nature and form of online privacy by critically analysing the issues surrounding the failed launch of Facebookâs advertising tool Beacon. Beacon is an interesting case study because it highlighted the complexity of information ownership in an online social network. Qualitative data was gathered from 29 weblogs (blogs) representing user opinions published between 6th November 2007(when Beacon was launched) and 28th February 2008 (when commentary had dwindled). A thematic analysis of the blogs suggest that concerns such as commercialism, terms of service (TOS), lack of user control, lack of user awareness and data protection are factors that influence user perceptions of information ownership as a subset of online privacy
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A heuristic evaluation of the Facebook's advertising tool beacon
Interface usability is critical to the successful adoption of information systems. The aim of this study is to evaluate interface of Facebook's advertising tool Beacon by using privacy heuristics [4]. Beacon represents an interesting case study because of the negative media and user backlash it received. The findings of heuristic evaluation suggest violation of privacy heuristics [4]. Here, analysis identified concerns about user choice and consent, integrity and security of data, and awareness and notice. Beacon was an innovative tool, therefore, its systematic evaluation was needed in order to identify privacy problems, their causes and subsequent consequences. The study provides useful insights to human computer interaction (HCI) designers of online social networks
On-line analysis of random vibrations
Measuring device, Randomdec, provides continuous on-line signatures representative of system free vibration curve. Selected points on curve are used in control and failure detection systems. Apparatus applied to both linear and nonlinear systems under nonstationary vibratory states
Perception of Patient Cooperation Among Dentist, Guardian, and Child
Purpose: Evaluate behavior assessment and agreement among dentist, guardian, and child. Evaluate child behavior by appointment type.
Methods: Patients recruited from the pediatric dental department at Virginia Commonwealth University for this convenience sample. Inclusion criteria: patients presenting for clinical exams and/or restorative treatment without the use of advanced behavior guidance between August 29, 2018, and March 7, 2019; ages 4-12-years-old; and scheduled with a single clinician. Appointments were stratified by difficulty. Behavior was assessed by dentist and caregiver using the Frankl Scale. Patient self-assessed cooperation using an age-appropriate modified Frankl Scale, developed for this study. Agreement assessed among the 3 scores at each appointment using descriptive statistics and Cohenâs Kappa. Behavior trends across appointment type assessed using Kruskal-Wallis test. SAS software (2013, Cary, NC). P-value \u3c 0.05.
Results: Forty-one patient-guardian dyads enrolled in the study. Five dyads experienced multiple encounters. Demographics for the patients enrolled: 59% male; 44% Caucasian, 29% African American, 5% Asian, 2% Hispanic, 20% other/multiracial. Average patient age: 7.6 (range: 4- 12). Most patients had 1 encounter (n=36, 88%). Frankl Score agreement for provider/guardian was 79% (k=0.335), provider/child was 70% (k=0.248), and guardian/child was 81% (k=0.314). In disagreements, guardians rated behavior better than provider. Disagreement was split for provider/child and guardian/child, with the child tending to rate themselves higher, and the guardian tending to rate the child higher respectively. Marginal evidence that hard appointments resulted in poorer behaviors.
Conclusion: There is fair agreement between child, guardian, and provider. In disagreements, guardians tend to rate the childâs behavior better compared to the provider and child self-assessment. Dental providers tend to be more critical of patient behavior. Marginal evidence to support harder appointments result in poorer behaviors
Financial Development, Bank Ownership, and Growth. Or, Does Quantity Imply Quality?
In 1980, India nationalized its large private banks. This induced different bank ownership patterns across different towns, allowing credible identification of the effects of bank ownership on financial development, lending rates, and the quality of intermediation, as well as employment and investment. Credit markets with nationalized banks experienced faster credit growth during a period of financial repression. Nationalization led to lower interest rates and lower quality intermediation, and may have slowed employment gains in trade and services. Development lending goals were met, but these had no impact on the real economy.
The star formation history of the Sculptor Dwarf Irregular Galaxy
[abridged] We study the resolved stellar populations and derive the SFH of
the SDIG, a gas-rich dwarf galaxy member of the NGC7793 subgroup in the
Sculptor group. We construct a CMD using archival HST observations and examine
its stellar content. We derive its SFH using a maximum-likelihood fit to the
CMD. The CMD shows that SDIG contains stars from 10Myr to several Gyr old, as
revealed from the MS, BL, luminous AGB, and RGB stars. The young stars with
ages less than ~250Myr show a spatial distribution confined to its central
regions, and additionally the young MS stars exhibit an off-center density
peak. The intermediate-age and older stars are more spatially extended. SDIG is
dominated by intermediate-age stars with an average age of 6.4Gyr. The average
metallicity inferred is [M/H]\approx -1.5dex. Its SFH is consistent with a
constant SFR, except for ages younger than ~200Myr. The lifetime average SFR is
1.3x10^{-3} Mo/yr. More recently than 100Myr, there has been a burst of SF at a
rate ~2-3 times higher than the average SFR. The inferred recent SFR from CMD
modelling is higher than inferred from the Ha flux of the galaxy; we interpret
this to mean that the upper end of the IMF is not being fully sampled due to
the low SFR. Additionally, an observed lack of bright blue stars in the CMD
could indicate a downturn in SFR on 10^7-yr timescales. A previous SF
enhancement appears to have occurred between 600-1100Myr ago, with amplitude
similar to the most recent 100Myr. Older bursts of similar peak SFR and
duration would not be resolvable with these data. The observed enhancements in
SF suggest that SDIG is able to sustain a complex SFH without the effect of
interactions with its nearest massive galaxy. Integrating the SFR over the
entire history of SDIG yields a total stellar mass 1.77x10^{7}Mo, and a current
V-band stellar mass-to-light ratio 3.2Mo/Lo.Comment: A&A accepted; 10 pages, 9 figure
Red Giants in the Small Magellanic Cloud. II. Metallicity Gradient and Age-Metallicity Relation
We present results from the largest CaII triplet line metallicity study of
Small Magellanic Cloud (SMC) field red giant stars to date, involving 3037
objects spread across approximately 37.5 sq. deg., centred on this galaxy. We
find a median metallicity of [Fe/H]=-0.99+/-0.01, with clear evidence for an
abundance gradient of -0.075+/-0.011 dex / deg. over the inner 5 deg. We
interpret the abundance gradient to be the result of an increasing fraction of
young stars with decreasing galacto-centric radius, coupled with a uniform
global age-metallicity relation. We also demonstrate that the age-metallicity
relation for an intermediate age population located 10kpc in front of the NE of
the Cloud is indistinguishable from that of the main body of the galaxy,
supporting a prior conjecture that this is a stellar analogue of the Magellanic
Bridge. The metal poor and metal rich quartiles of our RGB star sample (with
complementary optical photometry from the Magellanic Clouds Photometric Survey)
are predominantly older and younger than approximately 6Gyr, respectively.
Consequently, we draw a link between a kinematical signature, tentatively
associated by us with a disk-like structure, and the upsurges in stellar
genesis imprinted on the star formation history of the central regions of the
SMC. We conclude that the increase in the star formation rate around 5-6Gyr ago
was most likely triggered by an interaction between the SMC and LMC.Comment: To appear in MNRA
Red Giants in the Small Magellanic Cloud. I. Disk and Tidal Stream Kinematics
We present results from an extensive spectroscopic survey of field stars in
the Small Magellanic Cloud (SMC). 3037 sources, predominantly first-ascent red
giants, spread across roughly 37.5 sq. deg, are analysed. The line of sight
velocity field is dominated by the projection of the orbital motion of the SMC
around the LMC/Milky Way. The residuals are inconsistent with both a
non-rotating spheroid and a nearly face on disk system. The current sample and
previous stellar and HI kinematics can be reconciled by rotating disk models
with line of nodes position angle, theta, ~ 120-130 deg., moderate inclination
(i ~ 25-70 deg.), and rotation curves rising at 20-40 km/s/kpc. The metal-poor
stars exhibit a lower velocity gradient and higher velocity dispersion than the
metal-rich stars. If our interpretation of the velocity patterns as bulk
rotation is appropriate, then some revision to simulations of the SMC orbit is
required since these are generally tuned to the SMC disk line-of-nodes lying in
a NE-SW direction. Residuals show strong spatial structure indicative of
non-circular motions that increase in importance with increasing distance from
the SMC centre. Kinematic substructure in the north-west part of our survey
area is associated with the tidal tail or Counter-Bridge predicted by
simulations. Lower line-of-sight velocities towards the Wing and the larger
velocities just beyond the SW end of the SMC Bar are probably associated with
stellar components of the Magellanic Bridge and Counter-Bridge, respectively.
Our results reinforce the notion that the intermediate-age stellar population
of the SMC is subject to substantial stripping by external forces.Comment: To appear in MNRA
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