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An evaluation framework for stereo-based driver assistance
This is the post-print version of the Article - Copyright @ 2012 Springer VerlagThe accuracy of stereo algorithms or optical flow methods is commonly assessed by comparing the results against the Middlebury
database. However, equivalent data for automotive or robotics applications
rarely exist as they are difficult to obtain. As our main contribution, we introduce an evaluation framework tailored for stereo-based driver assistance able to deliver excellent performance measures while
circumventing manual label effort. Within this framework one can combine several ways of ground-truthing, different comparison metrics, and use large image databases.
Using our framework we show examples on several types of ground truthing techniques: implicit ground truthing (e.g. sequence recorded without a crash occurred), robotic vehicles with high precision sensors, and to a small extent, manual labeling. To show the effectiveness of our evaluation framework we compare three different stereo algorithms on
pixel and object level. In more detail we evaluate an intermediate representation
called the Stixel World. Besides evaluating the accuracy of the Stixels, we investigate the completeness (equivalent to the detection rate) of the StixelWorld vs. the number of phantom Stixels. Among many findings, using this framework enables us to reduce the number of phantom Stixels by a factor of three compared to the base parametrization. This base parametrization has already been optimized by test driving vehicles for distances exceeding 10000 km
Telemetry downlink interfaces and level-zero processing
The technical areas being investigated are as follows: (1) processing of space to ground data frames; (2) parallel architecture performance studies; and (3) parallel programming techniques. Additionally, the University administrative details and the technical liaison between New Mexico State University and Goddard Space Flight Center are addressed
IMEX evolution of scalar fields on curved backgrounds
Inspiral of binary black holes occurs over a time-scale of many orbits, far
longer than the dynamical time-scale of the individual black holes. Explicit
evolutions of a binary system therefore require excessively many time steps to
capture interesting dynamics. We present a strategy to overcome the
Courant-Friedrichs-Lewy condition in such evolutions, one relying on modern
implicit-explicit ODE solvers and multidomain spectral methods for elliptic
equations. Our analysis considers the model problem of a forced scalar field
propagating on a generic curved background. Nevertheless, we encounter and
address a number of issues pertinent to the binary black hole problem in full
general relativity. Specializing to the Schwarzschild geometry in Kerr-Schild
coordinates, we document the results of several numerical experiments testing
our strategy.Comment: 28 pages, uses revtex4. Revised in response to referee's report. One
numerical experiment added which incorporates perturbed initial data and
adaptive time-steppin
Investigations on alternative substances for control of apple scab - Results from Conidia germinating tests and experiments with plant extracts
The intention of this research project, which was supported within the "Bundesprogramm Ökologischer
Landbau", was to find alternatives for the control of Venturia inaequalis for the organic fruitgrower.
Beside the investigations on reducing the ascospore potential on fallen leaves, experiments
were conducted in laboratory, greenhouses and in orchard to test direct control of scab with different
plant extracts, concentrations and methods of extraction. Extracts from Inula viscosa, Quillaja
saponaria-bark, citrus-species (AGROMIL) and Saponaria officinalis revealed a distinct efficacy
against apple scab in greenhouse studies on apple seedlings. ELOT-VIS, CHITOPLANT, COMCAT,
MOOSEXTRAKT, SILIOPLANT und FZB 24 did not show sufficient efficacy with the application schedule
used for control of scab. Mixtures of Quillaja-saponine and sulphur reduced effectively apple scab
incidence. In an experiment concerning rain stability Citrus-extract and Quillaja-saponine showed a
lower efficacy against scab after a simulated rain of 5 mm. The screening of different supplements
to Citrus-extract as surfactants and adhesives revealed GREEMAX and BIOPLUSS as promising additives.
Both combinations showed an efficacy comparable to copperoxychloride corresponding to
400 g elementary copper per ha
Open-closed TQFTs extend Khovanov homology from links to tangles
We use a special kind of 2-dimensional extended Topological Quantum Field
Theories (TQFTs), so-called open-closed TQFTs, in order to extend Khovanov
homology from links to arbitrary tangles, not necessarily even. For every plane
diagram of an oriented tangle, we construct a chain complex whose homology is
invariant under Reidemeister moves. The terms of this chain complex are modules
of a suitable algebra A such that there is one action of A or A^op for every
boundary point of the tangle. We give examples of such algebras A for which our
tangle homology theory reduces to the link homology theories of Khovanov, Lee,
and Bar-Natan if it is evaluated for links. As a consequence of the Cardy
condition, Khovanov's graded theory can only be extended to tangles if the
underlying field has finite characteristic. In all cases in which the algebra A
is strongly separable, i.e. for Bar-Natan's theory in any characteristic and
for Lee's theory in characteristic other than 2, we also provide the required
algebraic operation for the composition of oriented tangles. Just as Khovanov's
theory for links can be recovered from Lee's or Bar-Natan's by a suitable
spectral sequence, we provide a spectral sequence in order to compute our
tangle extension of Khovanov's theory from that of Bar-Natan's or Lee's theory.
Thus, we provide a tangle homology theory that is locally computable and still
strong enough to recover characteristic p Khovanov homology for links.Comment: 56 pages, LaTeX2e with xypic and pstricks macro
Fine Structure of the Radial Breathing Mode in Double-Wall Carbon Nanotubes
The analysis of the Raman scattering cross section of the radial breathing
modes of double-wall carbon nanotubes allowed to determine the optical
transitions of the inner tubes. The Raman lines are found to cluster into
species with similar resonance behavior. The lowest components of the clusters
correspond well to SDS wrapped HiPco tubes. Each cluster represents one
particular inner tube inside different outer tubes and each member of the
clusters represents one well defined pair of inner and outer tubes. The number
of components in one cluster increases with decreasing of the inner tube
diameter and can be as high as 14.Comment: 5 pages, 3 figure
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