262,525 research outputs found
Quick Search for Rare Events
Rare events can potentially occur in many applications. When manifested as
opportunities to be exploited, risks to be ameliorated, or certain features to
be extracted, such events become of paramount significance. Due to their
sporadic nature, the information-bearing signals associated with rare events
often lie in a large set of irrelevant signals and are not easily accessible.
This paper provides a statistical framework for detecting such events so that
an optimal balance between detection reliability and agility, as two opposing
performance measures, is established. The core component of this framework is a
sampling procedure that adaptively and quickly focuses the
information-gathering resources on the segments of the dataset that bear the
information pertinent to the rare events. Particular focus is placed on
Gaussian signals with the aim of detecting signals with rare mean and variance
values
An Objective Bayesian Analysis of Life's Early Start and Our Late Arrival
Life emerged on the Earth within the first quintile of its habitable window,
but a technological civilization did not blossom until its last. Efforts to
infer the rate of abiogenesis, based on its early emergence, are frustrated by
the selection effect that if the evolution of intelligence is a slow process,
then life's early start may simply be a prerequisite to our existence, rather
than useful evidence for optimism. In this work, we interpret the chronology of
these two events in a Bayesian framework, extending upon previous work by
considering that the evolutionary timescale is itself an unknown that needs to
be jointly inferred, rather than fiducially set. We further adopt an objective
Bayesian approach, such that our results would be agreed upon even by those
using wildly different priors for the rates of abiogenesis and evolution -
common points of contention for this problem. It is then shown that the
earliest microfossil evidence for life indicates that the rate of abiogenesis
is at least 2.8 times more likely to be a typically rapid process, rather than
a slow one. This modest limiting Bayes factor rises to 8.7 if we accept the
more disputed evidence of C13 depleted zircon deposits (Bell et al. 2015). For
intelligence evolution, it is found that a rare-intelligence scenario is
slightly favored at 3:2 betting odds. Thus, if we re-ran Earth's clock, one
should statistically favor life to frequently re-emerge, but intelligence may
not be as inevitable
Probing new physics in decays by using angular asymmetries
We present the fully general, model independent study of a few rare
semileptonic decays that get dominant contributions from -annihilation
and -exchange diagrams, in particular ,
where . We consider the most general Lagrangian for the decay,
and define three angular asymmetries in the Gottfried-Jackson frame, which are
sensitive to new physics. We show how these angular asymmetries can be easily
extracted from the distribution of events in the Dalitz plot for decays. Especially a non-zero forward-backward asymmetry within
the frame would give the very first hint of possible new physics. These
observations are also true for related decay modes, such as and . Moreover, these asymmetry signatures
are not affected by either - or - mixings.
Then, this implies that both and as well as their CP conjugate modes can all be considered
together in our search for signature of new physics. Hence, it would be of
great importance to look for and study these decays in the laboratory, LHCb and
Belle II in particular.Comment: 5 pages, 2 figure
Research and Development Workstation Environment: the new class of Current Research Information Systems
Against the backdrop of the development of modern technologies in the field
of scientific research the new class of Current Research Information Systems
(CRIS) and related intelligent information technologies has arisen. It was
called - Research and Development Workstation Environment (RDWE) - the
comprehensive problem-oriented information systems for scientific research and
development lifecycle support. The given paper describes design and development
fundamentals of the RDWE class systems. The RDWE class system's generalized
information model is represented in the article as a three-tuple composite web
service that include: a set of atomic web services, each of them can be
designed and developed as a microservice or a desktop application, that allows
them to be used as an independent software separately; a set of functions, the
functional filling-up of the Research and Development Workstation Environment;
a subset of atomic web services that are required to implement function of
composite web service. In accordance with the fundamental information model of
the RDWE class the system for supporting research in the field of ontology
engineering - the automated building of applied ontology in an arbitrary domain
area, scientific and technical creativity - the automated preparation of
application documents for patenting inventions in Ukraine was developed. It was
called - Personal Research Information System. A distinctive feature of such
systems is the possibility of their problematic orientation to various types of
scientific activities by combining on a variety of functional services and
adding new ones within the cloud integrated environment. The main results of
our work are focused on enhancing the effectiveness of the scientist's research
and development lifecycle in the arbitrary domain area.Comment: In English, 13 pages, 1 figure, 1 table, added references in Russian.
Published. Prepared for special issue (UkrPROG 2018 conference) of the
scientific journal "Problems of programming" (Founder: National Academy of
Sciences of Ukraine, Institute of Software Systems of NAS Ukraine
- …