32,031 research outputs found
Analysis of Spectrum Occupancy Using Machine Learning Algorithms
In this paper, we analyze the spectrum occupancy using different machine
learning techniques. Both supervised techniques (naive Bayesian classifier
(NBC), decision trees (DT), support vector machine (SVM), linear regression
(LR)) and unsupervised algorithm (hidden markov model (HMM)) are studied to
find the best technique with the highest classification accuracy (CA). A
detailed comparison of the supervised and unsupervised algorithms in terms of
the computational time and classification accuracy is performed. The classified
occupancy status is further utilized to evaluate the probability of secondary
user outage for the future time slots, which can be used by system designers to
define spectrum allocation and spectrum sharing policies. Numerical results
show that SVM is the best algorithm among all the supervised and unsupervised
classifiers. Based on this, we proposed a new SVM algorithm by combining it
with fire fly algorithm (FFA), which is shown to outperform all other
algorithms.Comment: 21 pages, 6 figure
Optimization of aircraft seat cushion fire blocking layers
This report describes work completed by the National Aeronautics and Space Administration - for the Federal Aviation Administration Technical Center. The purpose of this work was to examine the potential of fire blocking mechanisms for aircraft seat cushions in order to provide an optimized seat configuration with adequate fire protection and minimum weight. Aluminized thermally stable fabrics were found to provide adequate fire protection when used in conjunction with urethane foams, while maintaining minimum weight and cost penalty
The case for emulating insect brains using anatomical "wiring diagrams" equipped with biophysical models of neuronal activity
Developing whole-brain emulation (WBE) technology would provide immense
benefits across neuroscience, biomedicine, artificial intelligence, and
robotics. At this time, constructing a simulated human brain lacks feasibility
due to limited experimental data and limited computational resources. However,
I suggest that progress towards this goal might be accelerated by working
towards an intermediate objective, namely insect brain emulation (IBE). More
specifically, this would entail creating biologically realistic simulations of
entire insect nervous systems along with more approximate simulations of
non-neuronal insect physiology to make "virtual insects." I argue that this
could be realistically achievable within the next 20 years. I propose that
developing emulations of insect brains will galvanize the global community of
scientists, businesspeople, and policymakers towards pursuing the loftier goal
of emulating the human brain. By demonstrating that WBE is possible via IBE,
simulating mammalian brains and eventually the human brain may no longer be
viewed as too radically ambitious to deserve substantial funding and resources.
Furthermore, IBE will facilitate dramatic advances in cognitive neuroscience,
artificial intelligence, and robotics through studies performed using virtual
insects.Comment: 25 pages, 2 figures. Biological Cybernetic
Adaptive guidance and control for future remote sensing systems
A unique approach to onboard processing was developed that is capable of acquiring high quality image data for users in near real time. The approach is divided into two steps: the development of an onboard cloud detection system; and the development of a landmark tracker. The results of these two developments are outlined and the requirements of an operational guidance and control system capable of providing continuous estimation of the sensor boresight position are summarized
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