8,481 research outputs found
Best Practices in Mental Health at Corrections Facilities
Police, court personnel, and correctional staff interact with, stabilize, and treat more persons with mental illness than any other system in America—making criminal justice agencies the largest mental health provider in the United States. Yet a wide gap exists between the training of corrections staff and the enormous responsibility they have for day-to-day management of mental health issues. To narrow this gap in jail and prison settings, the best practices include training programs, screening procedures, communication between staff, and good documentation. Quality mental health services help maintain security by reducing inmate and staff stress levels and helping to facilitate offender participation in rehabilitative programming. They increase the likelihood of successful reintegration of mentally ill offenders into the community by promoting adequate community based mental health care follow-up, thereby contributing to reduced recidivism. By following these best practices, correctional organizations can also reduce the likelihood of expensive civil litigation or other legal actions that can result from inadequate correctional mental health services
The Price of Information in Combinatorial Optimization
Consider a network design application where we wish to lay down a
minimum-cost spanning tree in a given graph; however, we only have stochastic
information about the edge costs. To learn the precise cost of any edge, we
have to conduct a study that incurs a price. Our goal is to find a spanning
tree while minimizing the disutility, which is the sum of the tree cost and the
total price that we spend on the studies. In a different application, each edge
gives a stochastic reward value. Our goal is to find a spanning tree while
maximizing the utility, which is the tree reward minus the prices that we pay.
Situations such as the above two often arise in practice where we wish to
find a good solution to an optimization problem, but we start with only some
partial knowledge about the parameters of the problem. The missing information
can be found only after paying a probing price, which we call the price of
information. What strategy should we adopt to optimize our expected
utility/disutility?
A classical example of the above setting is Weitzman's "Pandora's box"
problem where we are given probability distributions on values of
independent random variables. The goal is to choose a single variable with a
large value, but we can find the actual outcomes only after paying a price. Our
work is a generalization of this model to other combinatorial optimization
problems such as matching, set cover, facility location, and prize-collecting
Steiner tree. We give a technique that reduces such problems to their non-price
counterparts, and use it to design exact/approximation algorithms to optimize
our utility/disutility. Our techniques extend to situations where there are
additional constraints on what parameters can be probed or when we can
simultaneously probe a subset of the parameters.Comment: SODA 201
Generic absence of strong singularities and geodesic completeness in modified loop quantum cosmologies
Different regularizations of the Hamiltonian constraint in loop quantum
cosmology yield modified loop quantum cosmologies, namely mLQC-I and mLQC-II,
which lead to qualitatively different Planck scale physics. We perform a
comprehensive analysis of resolution of various singularities in these modified
loop cosmologies using effective spacetime description and compare with earlier
results in standard loop quantum cosmology. We show that the volume remains
non-zero and finite in finite time evolution for all considered loop
cosmological models. Interestingly, even though expansion scalar and energy
density are bounded due to quantum geometry, curvature invariants can still
potentially diverge due to pressure singularities at a finite volume. These
divergences are shown to be harmless since geodesic evolution does not break
down and no strong singularities are present in the effective spacetimes of
loop cosmologies. Using a phenomenological matter model, various types of
exotic strong and weak singularities, including big rip, sudden, big freeze and
type-IV singularities, are studied. We show that as in standard loop quantum
cosmology, big rip and big freeze singularities are resolved in mLQC-I and
mLQC-II, but quantum geometric effects do not resolve sudden and type-IV
singularities.Comment: Minor revision to match published version in CQ
Resolution of strong singularities and geodesic completeness in loop quantum Bianchi-II spacetimes
Generic resolution of singularities and geodesic completeness in the loop
quantization of Bianchi-II spacetimes with arbitrary minimally coupled matter
is investigated. Using the effective Hamiltonian approach, we examine two
available quantizations: one based on the connection operator and second by
treating extrinsic curvature as connection via gauge fixing. It turns out that
for the connection based quantization, either the inverse triad modifications
or imposition of weak energy condition is necessary to obtain a resolution of
all strong singularities and geodesic completeness. In contrast, the extrinsic
curvature based quantization generically resolves all strong curvature
singularities and results in a geodesically complete effective spacetime
without inverse triad modifications or energy conditions. In both the
quantizations, weak curvature singularities can occur resulting from
divergences in pressure and its derivatives at finite densities. These are
harmless events beyond which geodesics can be extended. Our work generalizes
previous results on the generic resolution of strong singularities in the loop
quantization of isotropic, Bianchi-I and Kantowski-Sachs spacetimes.Comment: 24 pages. Revised version to appear in CQG. Clarifications on
quantization prescriptions and triad orientations adde
Collaborative Reuse of Streaming Dataflows in IoT Applications
Distributed Stream Processing Systems (DSPS) like Apache Storm and Spark
Streaming enable composition of continuous dataflows that execute persistently
over data streams. They are used by Internet of Things (IoT) applications to
analyze sensor data from Smart City cyber-infrastructure, and make active
utility management decisions. As the ecosystem of such IoT applications that
leverage shared urban sensor streams continue to grow, applications will
perform duplicate pre-processing and analytics tasks. This offers the
opportunity to collaboratively reuse the outputs of overlapping dataflows,
thereby improving the resource efficiency. In this paper, we propose
\emph{dataflow reuse algorithms} that given a submitted dataflow, identifies
the intersection of reusable tasks and streams from a collection of running
dataflows to form a \emph{merged dataflow}. Similar algorithms to unmerge
dataflows when they are removed are also proposed. We implement these
algorithms for the popular Apache Storm DSPS, and validate their performance
and resource savings for 35 synthetic dataflows based on public OPMW workflows
with diverse arrival and departure distributions, and on 21 real IoT dataflows
from RIoTBench.Comment: To appear in IEEE eScience Conference 201
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