182 research outputs found
Fool me once: Can indifference vindicate induction?
Roger White (2015) sketches an ingenious new solution to the problem of induction. He argues from the principle of indifference for the conclusion that the world is more likely to be induction- friendly than induction-unfriendly. But there is reason to be skeptical about the proposed indifference-based vindication of induction. It can be shown that, in the crucial test cases White concentrates on, the assumption of indifference renders induction no more accurate than random guessing. After discussing this result, the paper explains why the indifference-based argument seemed so compelling, despite ultimately being unsound
The IC2118 association: new T Tauri stars in high-latitude molecular clouds
We identified new pre-main sequence stars in the region of high-latitude
molecular clouds associated with the reflection nebula IC2118, around l = 208
degr and b = -27 degr. The stars were selected as T Tauri candidates in
objective prism plates obtained with the Schmidt telescope of Konkoly
Observatory. Results of spectroscopic follow-up observations, carried out with
the FLAIR spectrograph installed on the UK Schmidt and with ALFOSC on Nordic
Optical Telescope, are presented in this paper. Based on spectral types,
presence of emission lines and lithium absorption line, we identified five
classical T Tauri stars and a candidate weak-line T Tauri star projected on the
molecular clouds, as well as two candidate pre-main sequence stars outside the
nebulous region. Using the near infrared magnitudes obtained from the 2MASS All
Sky Catalog. we determined the masses and ages of these stars. We found that
the five classical T Tauri stars projected on the clouds are physically related
to them, whereas the other stars are probably background objects. Adopting a
distance of 210 pc for IC2118 (Kun et al. 2001) and using Palla & Stahler's
(1999) evolutionary tracks we derived an average age of 2.5 million yrs and a
mass interval of 0.4--1.0 M_sun for the members of the IC2118 association.Comment: 11 pages, 6 figures, accepted for publication by Astronomy and
Astrophysic
CVABS: Moving Object Segmentation with Common Vector Approach for Videos
Background modelling is a fundamental step for several real-time computer
vision applications that requires security systems and monitoring. An accurate
background model helps detecting activity of moving objects in the video. In
this work, we have developed a new subspace based background modelling
algorithm using the concept of Common Vector Approach with Gram-Schmidt
orthogonalization. Once the background model that involves the common
characteristic of different views corresponding to the same scene is acquired,
a smart foreground detection and background updating procedure is applied based
on dynamic control parameters. A variety of experiments is conducted on
different problem types related to dynamic backgrounds. Several types of
metrics are utilized as objective measures and the obtained visual results are
judged subjectively. It was observed that the proposed method stands
successfully for all problem types reported on CDNet2014 dataset by updating
the background frames with a self-learning feedback mechanism.Comment: 12 Pages, 4 Figures, 1 Tabl
Recommended from our members
Homelessness and Public Health in Los Angeles
Los Angeles faces a housing crisis of unprecedented scale. After years of underinvestment, in 2016/2017 LA County voters approved Measures H and HHH, which provided an infusion of resources for homeless services, permanent housing, and integrated outreach through the LA County Homeless Initiative (HI). An estimated 58,936 individuals in LA County remain homeless as of January 2019, 75% of them unsheltered and living on streets, in tents, or encampments. Our best estimates suggest that the homeless population has grown since 2017.HI takes a Housing First approach to homelessness, with the largest amount of total funds allocated to housing solutions. However, rehousing is often subject to delays in construction and case management. These delays, combined with persistent market forces driving new homelessness, have left the county well short of its targets. While no forecasts were issued, the initial gap analysis for HI had assumed a 34% reduction in the total homeless count from 2016 to 2019. The count has in fact increased by 26% over that period, meaning 28,000 more homeless clients than anticipated on any night. Whereas cities with comparable homeless crises such as New York have focused on increasing the availability of emergency shelters and safe havens in addition to permanent housing, LA County’s relatively low investment in transitional options has resulted in persistent levels of unsheltered homelessness.Research has shown that homelessness has severe health consequences. Homeless individuals have a high risk of mortality, with a recent LA County Medical Examiner report finding an average age of death of 48 for women and 51 for men. Homeless individuals have much higher risks of mental illness, substance abuse, infectious disease, chronic illness, violence, and reproductive health risks than the general population. Much less is known about the health burdens associated with being unsheltered, but most evidence points to substantially greater health risks given the more intense exposures to violence, weather, pollution, poor sanitation, and behavioral risk. Research is just beginning to quantify the burdens of living on the streets.Our analysis of the LA County homelessness response drew on expert interviews, data analysis, and document review. Beyond the growing numerical gap between HI’s targets and actual trends, we identified five critical service gaps that require immediate attention: Taking a person-centered approach that recognizes both the diversity of client needs and the limitations of existing resources, yet honors the principle that everyone deserves housing; Improving access to emergency shelters by reducing legal and political barriers to construction and adopting “low barrier shelters” that facilitate entry; Delivering comprehensive street medicine and other services to unsheltered homeless populations using evidence-based models that support the path to housing and recovery Adopting more extensive outreach models that engage citizens, empower homeless clients and leverage mobile technology so that case workers can focus on clients most in need; Strengthening data collection and research methods to understand the consequences of unsheltered homelessness, pilot new service models, and evaluate rehousing efforts
Motion Detection in High Resolution Enhancement
Shifted Superposition (SSPOS) is a resolution enhancement methodwhere apparent high-resolution content is displayed using a lowresolutionprojection system with an opto-mechanical shifter. WhileSSPOS-enhanced projectors have been showing promising resultsin still images, they still suffer from motion artifacts in video contents.Motivated by this, we present a novel approach to apparentprojector resolution enhancement for videos via motion-basedblurring module. We propose the use of a motion detection moduleand a blurring module to compensate for both SSPOS-resulted andnatural motion artifacts in the video content. To accomplish this,we combine both local and global motion estimation algorithms togenerate accurate dense flow fields. The detected motion regionsare enhanced using directional Gaussian filters. Preliminary resultsshow that the proposed method can produce accurate densemotion vectors and significantly reduce the artifacts in videos
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