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A Transfer Operator Methodology for Optimal Sensor Placement Accounting for Uncertainty
Sensors in buildings are used for a wide variety of applications such as
monitoring air quality, contaminants, indoor temperature, and relative
humidity. These are used for accessing and ensuring indoor air quality, and
also for ensuring safety in the event of chemical and biological attacks. It
follows that optimal placement of sensors become important to accurately
monitor contaminant levels in the indoor environment. However, contaminant
transport inside the indoor environment is governed by the indoor flow
conditions which are affected by various uncertainties associated with the
building systems including occupancy and boundary fluxes. Therefore, it is
important to account for all associated uncertainties while designing the
sensor layout. The transfer operator based framework provides an effective way
to identify optimal placement of sensors. Previous work has been limited to
sensor placements under deterministic scenarios. In this work we extend the
transfer operator based approach for optimal sensor placement while accounting
for building systems uncertainties. The methodology provides a probabilistic
metric to gauge coverage under uncertain conditions. We illustrate the
capabilities of the framework with examples exhibiting boundary flux
uncertainty
Quintom cosmologies admitting either tracking or phantom attractors
In this paper we investigate the evolution of a class of cosmologies fuelled
by quintom dark energy and dark matter. Quintom dark energy is a hybrid of
quintessence and phantom which involves the participation of two reals scalar
fields playing the roles of those two types of dark energy. In that framework
we examine from a dynamical systems perspective the possibility that those
fields are coupled among them by considering an exponential potential with an
interesting functional dependence similar but not identical to others studied
before. The model we consider represents a counterexample to the typical
behavior of quintom models with exponential potentials because it admits either
tracking attractors (), or phantom attractors ().Comment: revtex4, 7 pages, 6 figure
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