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Evaluation of Non-photorealistic 3D Urban Models for Mobile Device Navigation.
PEN as self-vetoing structural Material
Polyethylene Naphtalate (PEN) is a mechanically very favorable polymer.
Earlier it was found that thin foils made from PEN can have very high
radio-purity compared to other commercially available foils. In fact, PEN is
already in use for low background signal transmission applications (cables).
Recently it has been realized that PEN also has favorable scintillating
properties. In combination, this makes PEN a very promising candidate as a
self-vetoing structural material in low background experiments. Components
instrumented with light detectors could be built from PEN. This includes
detector holders, detector containments, signal transmission links, etc. The
current R\&D towards qualification of PEN as a self-vetoing low background
structural material is be presented.Comment: 4 pages, 7 figures, contribution to Proceedings of the sixth workshop
on Low Radioactivity Techniques 2017, 23-27 May 2017 Seoul, to be published
at AIP, editor: D. Leonar
Characterisation of an n-type segmented BEGe detector
A four-fold segmented n-type point-contact "Broad Energy" high-purity
germanium detector, SegBEGe, has been characterised at the Max-Planck-Institut
f\"ur Physik in Munich. The main characteristics of the detector are described
and first measurements concerning the detector properties are presented. The
possibility to use mirror pulses to determine source positions is discussed as
well as charge losses observed close to the core contact
Mean value coordinates–based caricature and expression synthesis
We present a novel method for caricature synthesis based on mean value coordinates (MVC). Our method can be applied to any single frontal face image to learn a specified caricature face pair for frontal and 3D caricature synthesis. This technique only requires one or a small number of exemplar pairs and a natural frontal face image training set, while the system can transfer the style of the exemplar pair across individuals. Further exaggeration can be fulfilled in a controllable way. Our method is further applied to facial expression transfer, interpolation, and exaggeration, which are applications of expression editing. Additionally, we have extended our approach to 3D caricature synthesis based on the 3D version of MVC. With experiments we demonstrate that the transferred expressions are credible and the resulting caricatures can be characterized and recognized
The Unusual Superconducting State at 49 K in Electron-Doped CaFe2As2 at Ambient
We report the detection of unusual superconductivity up to 49 K in single
crystalline CaFe2As2 via electron-doping by partial replacement of Ca by
rare-earth. The superconducting transition observed suggests the possible
existence of two phases: one starting at ~ 49 K, which has a low critical field
~ 4 Oe, and the other at ~ 21 K, with a much higher critical field > 5 T. Our
observations are in strong contrast to previous reports of doping or
pressurizing layered compounds AeFe2As2 (or Ae122), where Ae = Ca, Sr or Ba. In
Ae122, hole-doping has been previously observed to generate superconductivity
with a transition temperature (Tc) only up to 38 K and pressurization has been
reported to produce superconductivity with a Tc up to 30 K. The unusual 49 K
phase detected will be discussed.Comment: 11 pages, 8 figure
Pressure shift of the superconducting T_c of LiFeAs
The effect of hydrostatic pressure on the superconductivity in LiFeAs is
investigated up to 1.8 GPa. The superconducting transition temperature, T_c,
decreases linearly with pressure at a rate of 1.5 K/GPa. The negative pressure
coefficient of T_c and the high ambient pressure T_c indicate that LiFeAs is
the high-pressure analogue of the isoelectronic SrFe_2As_2 and BaFe_2As_2.Comment: 3 pages, 2 figure
Overview on spectral line source finding and visualisation
Here I will outline successes and challenges for finding spectral line
sources in large data cubes that are dominated by noise. This is a 3D challenge
as the sources we wish to catalog are spread over several spatial pixels and
spectral channels. While 2D searches can be applied, e.g., channel by channel,
optimal searches take into account the 3-dimensional nature of the sources. In
this overview I will focus on HI 21-cm spectral line source detection in
extragalactic surveys, in particular HIPASS, the "HI Parkes All-Sky Survey" and
WALLABY, the "ASKAP HI All-Sky Survey". I use the original HIPASS data to
highlight the diversity of spectral signatures of galaxies and gaseous clouds,
both in emission and absorption. Among others, I report the discovery of a 680
km/s wide HI absorption trough in the megamaser galaxy NGC 5793. Issues such as
source confusion and baseline ripples, typically encountered in single-dish HI
surveys, are much reduced in interferometric HI surveys. Several large HI
emission and absorption surveys are planned for the Australian Square Kilometre
Array Pathfinder (ASKAP): here we focus on WALLABY, the 21-cm survey of the sky
(Dec < +30 degr; z < 0.26) which will take about one year of observing time
with ASKAP. Novel phased array feeds ("radio cameras") will provide 30 square
degrees instantaneous field-of-view. WALLABY is expected to detect more than
500 000 galaxies, unveil their large-scale structures and cosmological
parameters, detect their extended, low-surface brightness disks as well as gas
streams and filaments between galaxies. It is a precursor for future HI surveys
with SKA Phase I and II, exploring galaxy formation and evolution. The
compilation of highly reliable and complete source catalogs will require
sophisticated source-finding algorithms as well as accurate source
parametrisation.Comment: 14 pages, 6 figures, PASA Special Issue on "Source Finding &
Visualisation", submitte
HI Detection in two Dwarf S0 Galaxies in Nearby Groups: ESO384-016 and NGC 59
An \hi survey of 10 dE/dS0 galaxies in the nearby Sculptor and Centaurus A
groups was made using the Australia Telescope Compact Array (ATCA). The
observed galaxies have accurate distances derived by Jerjen et al (1998; 2000b)
using the surface brightness fluctuation technique. Their absolute magnitudes
are in the range . Only two of the ten galaxies were
detected at our detection limit ( \msol for the Centaurus
group and \msol for the Sculptor group), the two dS0
galaxies ESO384-016 in the Centaurus A Group and NGC 59 in the Sculptor Group,
with \hi masses of \msol and \msol respectively. Those two detections were confirmed using the Green
Bank Telescope. These small \hi reservoirs could fuel future generations of low
level star formation and could explain the bluer colors seen at the center of
the detected galaxies. Similarly to what is seen with the Virgo dEs, the two
objects with \hi appear to be on the outskirt of the groups.Comment: 25 pages (11 figures), accepted by A
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