2,265 research outputs found
Label Placement in Road Maps
A road map can be interpreted as a graph embedded in the plane, in which each
vertex corresponds to a road junction and each edge to a particular road
section. We consider the cartographic problem to place non-overlapping road
labels along the edges so that as many road sections as possible are identified
by their name, i.e., covered by a label. We show that this is NP-hard in
general, but the problem can be solved in polynomial time if the road map is an
embedded tree.Comment: extended version of a CIAC 2015 pape
An Algorithmic Framework for Labeling Road Maps
Given an unlabeled road map, we consider, from an algorithmic perspective,
the cartographic problem to place non-overlapping road labels embedded in their
roads. We first decompose the road network into logically coherent road
sections, e.g., parts of roads between two junctions. Based on this
decomposition, we present and implement a new and versatile framework for
placing labels in road maps such that the number of labeled road sections is
maximized. In an experimental evaluation with road maps of 11 major cities we
show that our proposed labeling algorithm is both fast in practice and that it
reaches near-optimal solution quality, where optimal solutions are obtained by
mixed-integer linear programming. In comparison to the standard OpenStreetMap
renderer Mapnik, our algorithm labels 31% more road sections in average.Comment: extended version of a paper to appear at GIScience 201
Tightly Correlated HI and FUV Emission in the Outskirts of M83
We compare sensitive HI data from The HI Nearby Galaxy Survey (THINGS) and
deep far UV (FUV) data from GALEX in the outer disk of M83. The FUV and HI maps
show a stunning spatial correlation out to almost 4 optical radii (r25),
roughly the extent of our maps. This underscores that HI traces the gas
reservoir for outer disk star formation and it implies that massive (at least
low level) star formation proceeds almost everywhere HI is observed. Whereas
the average FUV intensity decreases steadily with increasing radius before
leveling off at ~1.7 r25, the decline in HI surface density is more subtle. Low
HI columns (<2 M_solar/pc^2) contribute most of the mass in the outer disk,
which is not the case within r25. The time for star formation to consume the
available HI, inferred from the ratio of HI to FUV intensity, rises with
increasing radius before leveling off at ~100 Gyr, i.e., many Hubble times,
near ~1.7 r25. Assuming the relatively short H2 depletion times observed in the
inner parts of galaxies hold in outer disks, the conversion of HI into bound,
molecular clouds seems to limit star formation in outer galaxy disks. The long
consumption times suggest that most of the extended HI observed in M83 will not
be consumed by in situ star formation. However, even these low star formation
rates are enough to expect moderate chemical enrichment in a closed outer disk.Comment: Accepted for Publication in ApJ
Nonverbale Synchronie und Musik-Erleben im klassischen Konzert
Die Praxis der Musikrezeption im Rahmen klassischer Konzerte ist von restriktiven Verhaltenskonventionen geprägt. Aktuelle kognitionswissenschaftliche und philosophische Ansätze, welche Musik-Erleben als verkörpert oder als über mehrere Individuen verteilt konzeptualisieren, scheinen daher für die Erklärung des Musik-Erlebens in klassischen Konzerten weniger geeignet. Vor diesem Hintergrund untersuchte die vorliegende explorative Studie das Auftreten koordinierter Körperbewegungen als nonverbale Synchronie im Rahmen eines klassischen Konzertes und den Zusammenhang zwischen den Synchronien innerhalb des Publikums und Aspekten des subjektiven Musik-Erlebens. Im Rahmen eines Forschungskonzerts wurden 22 Teilnehmern verschiedene Kammermusikwerke präsentiert, sowie dabei Selbstauskünfte zu Aspekten des Musik-Erlebens erhoben und Körperbewegungen mit drei stationären Kameras erfasst. Nonverbale Synchronie, als Indikator für koordinierte Körperbewegungen, wurde über die Korrelation von Bewegungsenergie-Zeitreihen ermittelt. Die Bewegungsenergie wurde als Anzahl der sich ändernden Pixel aufeinanderfolgender Frames operationalisiert. Es zeigte sich stark ausgeprägte Synchronie zwischen den Musikern sowie eine Synchronie kleiner bis mittlerer Effektstärke innerhalb des Publikums. Zwischen den Musikern und dem Publikum konnte hingegen keine Synchronie festgestellt werden. In Bezug auf das Verhältnis von Synchronie innerhalb des Publikums und dem subjektiven Musik-Erleben zeigten sich signifikante negative Zusammenhänge zwischen dem Gefühl der Verbundenheit mit den Musikern, dem Grad der Absorption und der Synchronisierung innerhalb des Publikums. Dies lässt sich dahingehend interpretieren, dass bei einem stärkeren Fokus der Aufmerksamkeit und des Erlebens auf das Bühnengeschehen die Synchronisierung mit den anderen Mitgliedern des Publikums abnimmt. Die Ergebnisse dieser Studie stehen im Einklang mit Theorien zum verkörperten Musik-Erleben, sie stützen jedoch Ansätze nicht, die darunter die Nachahmung der klangproduzierenden Bewegungen der Musiker verstehen. Ebenso stehen die Befunde nicht in Einklang mit Ansätzen zum verteilten Musik-Erleben. Abschließend werden die Ergebnisse hinsichtlich ihrer musikpraktischen Relevanz bezüglich einer Diversifizierung klassischer Konzerte diskutiert
Multitouch Experiment Instruction and Self-Regulation: Promoting Self-Regulation with a Multitouch Experiment Instruction on the topic of water analysis
In context of Education for Sustainable Development (ESD), the range of experiments offered by the Schülerlabor NanoBioLab at Saarland University was expanded to include an experiment on the topic of water analysis, which provided the basis of the intervention. In addition to the analogue experiment instruction, there is a digital version which is presented as a Multitouch Experiment Instruction (MEI). MEIs are digitally enriched, interactive experiment instructions that accompany the cognitive learning process of pupils and promote competencies in the digital world (Seibert et al., 2020). In this study, we analysed whether the MEI could support self-regulated learning in an indirect support approach by considering different hierarchical levels of self-regulation in the design of the materials. The results show a significant acquisition of self-regulatory competences of learners in grades ten and eleven by using the MEI compared to the analogue version
The Effects of Diffuse Ionized Gas and Spatial Resolution on Metallicity Gradients: TYPHOON Two-Dimensional Spectrophotometry of M83
We present a systematic study of the diffuse ionized gas (DIG) in M83 and its
effects on the measurement of metallicity gradients at varying resolution
scales. Using spectrophotometric data cubes of M83 obtained at the 2.5m duPont
telescope at Las Campanas Observatory as part of the TYPHOON program, we
separate the HII regions from the DIG using the [SII]/H ratio, HIIphot
(HII finding algorithm) and the H surface brightness. We find that the
contribution to the overall H luminosity is approximately equal for the
HII and DIG regions. The data is then rebinned to simulate low-resolution
observations at varying resolution scales from 41 pc up to 1005 pc. Metallicity
gradients are measured using five different metallicity diagnostics at each
resolution. We find that all metallicity diagnostics used are affected by the
inclusion of DIG to varying degrees. We discuss the reasons of why the
metallicity gradients are significantly affected by DIG using the HII dominance
and emission line ratio radial profiles. We find that applying the
[SII]/H cut will provide a closer estimate of the true metallicity
gradient up to a resolution of 1005 pc for all metallicity diagnostics used in
this study.Comment: 26 pages, 12 figures + Appendix/Supplementary Material, accepted for
publication by MNRA
Hadron widths in mixed-phase matter
We derive classically an expression for a hadron width in a two-phase region
of hadron gas and quark-gluon plasma (QGP). The presence of QGP gives hadrons
larger widths than they would have in a pure hadron gas. We find that the
width observed in a central Au+Au collision at
GeV/nucleon is a few MeV greater than the width in a pure hadron gas. The part
of observed hadron widths due to QGP is approximately proportional to
.Comment: 8 pages, latex, no figures, KSUCNR-002-9
Starburst-AGN mixing: TYPHOON observations of NGC 1365, NGC 1068, and the effect of spatial resolution on the AGN fraction
We demonstrate a robust method of resolving the star-formation and AGN
contributions to emission lines using two very well known AGN systems: NGC
1365, and NGC 1068, using the high spatial resolution data from the
TYPHOON/PrISM survey. We expand the previous method of calculating the AGN
fraction by using theoretical-based model grids rather than empirical points.
The high spatial resolution of the TYPHOON/PrISM observations show evidence of
both star formation and AGN activity occurring in the nuclei of the two
galaxies. We rebin the data to the lower resolutions, typically found in other
integral field spectroscopy surveys such as SAMI, MaNGA, and CALIFA. The
results show that when rebinned from the native resolution of TYPHOON (< 200
pc/pixel) to 1 kpc/pixel, the effects include a roughly 3 kpc increase in the
radius of measured AGN activity, and a factor of 2 to 7 increase in the
detection of low surface brightness features such as shocks. All of this
information is critical, because information on certain physical processes may
be lost at varying resolutions. We make recommendations for analysing data at
current IFU survey resolutions.Comment: 30 pages, 28 figures, accepted for publication by MNRA
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