288 research outputs found
A New Approach To Estimate The Collision Probability For Automotive Applications
We revisit the computation of probability of collision in the context of
automotive collision avoidance (the estimation of a potential collision is also
referred to as conflict detection in other contexts). After reviewing existing
approaches to the definition and computation of a collision probability we
argue that the question "What is the probability of collision within the next
three seconds?" can be answered on the basis of a collision probability rate.
Using results on level crossings for vector stochastic processes we derive a
general expression for the upper bound of the distribution of the collision
probability rate. This expression is valid for arbitrary prediction models
including process noise. We demonstrate in several examples that distributions
obtained by large-scale Monte-Carlo simulations obey this bound and in many
cases approximately saturate the bound. We derive an approximation for the
distribution of the collision probability rate that can be computed on an
embedded platform. In order to efficiently sample this probability rate
distribution for determination of its characteristic shape an adaptive method
to obtain the sampling points is proposed. An upper bound of the probability of
collision is then obtained by one-dimensional numerical integration over the
time period of interest. A straightforward application of this method applies
to the collision of an extended object with a second point-like object. Using
an abstraction of the second object by salient points of its boundary we
propose an application of this method to two extended objects with arbitrary
orientation. Finally, the distribution of the collision probability rate is
identified as the distribution of the time-to-collision.Comment: Revised and restructured version, discussion of extended vehicles
expanded, section on TTC expanded, references added, other minor changes, 17
pages, 18 figure
Partial Supersymmetry Breaking from Five Dimensions
Theories of partial supersymmetry breaking N=2 -> N=1 in four dimensions are
derived by coupling the N=2 massless gravitino multiplet to N=2 supergravity in
five dimensions and performing a generalized dimensional reduction on S^1/Z_2
with the Scherk-Schwarz mechanism. These theories agree with results that were
previously derived from four dimensions.Comment: 15 pages, Latex; introduction slightly changed, one reference adde
Effect of Positive Role Model on Young Girls
Richard RosenkranzThis project focuses on the effect that an older role model or mentor can have on a younger girl regarding her attitude toward health and self-image. It looks at attitudes toward exercise, eating habits, self-esteem, and various other health topics. The data was collected through Wildcat Wellness Coaching, and the subjects were young females generally between the ages of 8 and 12. Some of the girls were exposed to Wildcat Wellness Coaching that taught them how to prepare healthy snacks and make exercising more fun. The other girls were exposed to Wildcat Wellness Coaching that taught them about important health topics that may affect them in the future. This program allowed them to meet with a coach weekly for about an hour. Each semester the participants were different and their progress was monitored from start to finish. Results showed a change in attitude of the girls who participated in one of the interventions, but not in the other
Implications of Non-universal Soft Masses on Gauge Coupling Unification
We study the gauge coupling unification of the minimal supersymmetric
standard model with non-universal soft scalar and gaugino masses. The
unification scale of the gauge couplings is estimated for non-universal cases.
It is sensitive to the non-universality. It turns out that these cases can be
combined with the assumption of string unification, which leads to a prediction
of and , the normalisation of the
generator. String unification predicts . These values have
non-trivial implications on string model building. Two-loop corrections are
also calculated. Some of these cases exhibit a large discrepancy between
experiment and string unification. We calculate string threshold corrections to
explain the discrepancy.Comment: 25 pages, Latex, 4 figures (not included
N=6 gauged supergravities from generalized dimensional reduction
We construct new N=6 gauged supergravities in four and five dimensions using
generalized dimensional reduction. Supersymmetry is spontaneously broken to
N=4,2,0 with vanishing cosmological constant. We discuss the gaugings of the
broken phases, the scalar geometries and the spectrum. Generalized orbifold
reduction is also considered and an N=3 no-scale model is obtained with three
independent mass parameters.Comment: 1+9 pages, accepted for publication in Physics Letters
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