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Estimation of energy and material use of sintering-based construction for a lunar outpost - with the example of SinterHab module design
In this paper, we would revisit the usability of microwave for lunar regolith sintering through an in-depth experiment, and examine the minimum materials and energy required for sintering based on the SinterHab design. This will include the minimum layers to print, estimated printing time, minimum energy required for the sintering process and the potential energy sources
Spatio-temporal variation of conversational utterances on Twitter
Conversations reflect the existing norms of a language. Previously, we found
that utterance lengths in English fictional conversations in books and movies
have shortened over a period of 200 years. In this work, we show that this
shortening occurs even for a brief period of 3 years (September 2009-December
2012) using 229 million utterances from Twitter. Furthermore, the subset of
geographically-tagged tweets from the United States show an inverse proportion
between utterance lengths and the state-level percentage of the Black
population. We argue that shortening of utterances can be explained by the
increasing usage of jargon including coined words.Comment: 13 pages, 7 figures, published in PLoS On
Free Form Lensing Implications for the Collision of Dark Matter and Gas in the Frontier Fields Cluster MACSJ0416.1-2403
We present a free form mass reconstruction of the massive lensing cluster
MACSJ0416.1-2403 using the latest Hubble Frontier Fields data. Our model
independent method finds that the extended lensing pattern is generated by two
elongated, closely projected clusters of similar mass. Our lens model
identifies new lensed images with which we improve the accuracy of the dark
matter distribution. We find that the bimodal mass distribution is nearly
coincident with the bimodal X-ray emission, but with the two dark matter peaks
lying closer together than the centroids of the X-ray emisison. We show this
can be achieved if the collision has occurred close to the plane and such that
the cores are deflected around each other. The projected mass profiles of both
clusters are well constrained because of the many interior lensed images,
leading to surprisingly flat mass profiles of both components in the region
15-100 kpc. We discuss the extent to which this may be generated by tidal
forces in our dynamical model which are large during an encounter of this type
as the cores "graze" each other. The relative velocity between the two cores is
estimated to be about 1200 km/s and mostly along the line of sight so that our
model is consistent with the relative redshift difference between the two cD
galaxies (dz = 0.04).Comment: 22 pages, 18 figures, 2 table
Epidemiology and control of Phytophthora botryosa on rubber in Malaysia.
Suplemento. Edição dos resumos do 17º Congresso da Sociedade Brasileira de Fitopatologia, 1984
Design of magnetic traps for neutral atoms with vortices in type-II superconducting micro-structures
We design magnetic traps for atoms based on the average magnetic field of
vortices induced in a type-II superconducting thin film. This magnetic field is
the critical ingredient of the demonstrated vortex-based atom traps, which
operate without transport current. We use Bean's critical-state method to model
the vortex field through mesoscopic supercurrents induced in the thin strip.
The resulting inhomogeneous magnetic fields are studied in detail and compared
to those generated by multiple normally-conducting wires with transport
currents. Various vortex patterns can be obtained by programming different
loading-field and transport current sequences. These variable magnetic fields
are employed to make versatile trapping potentials.Comment: 11 pages, 14 figure
Molecular Gas in the Powerful Radio Galaxies 3C~31 and 3C~264: Major or Minor Mergers?
We report the detection of CO~() and CO~()
emission from the central regions (--) of the two
powerful radio galaxies 3C~31 and 3C~264. Their individual CO emission exhibits
a double-horned line profile that is characteristic of an inclined rotating
disk with a central depression at the rising part of its rotation curve. The
inferred disk or ring distributions of the molecular gas is consistent with the
observed presence of dust disks or rings detected optically in the cores of
both galaxies. For a CO to H conversion factor similar to that of our
Galaxy, the corresponding total mass in molecular hydrogen gas is in 3C~31 and in 3C~264. Despite their relatively large molecular-gas masses
and other peculiarities, both 3C~31 and 3C~264, as well as many other powerful
radio galaxies in the (revised) 3C catalog, are known to lie within the
fundamental plane of normal elliptical galaxies. We reason that if their gas
originates from the mergers of two gas-rich disk galaxies, as has been invoked
to explain the molecular gas in other radio galaxies, then both 3C~31 and
3C~264 must have merged a long time (a few billion years or more) ago but their
remnant elliptical galaxies only recently (last tens of millions of years or
less) become active in radio. Instead, we argue that the cannibalism of
gas-rich galaxies provides a simpler explanation for the origin of molecular
gas in the elliptical hosts of radio galaxies. Given the transient nature of
their observed disturbances, these galaxies probably become active in radio
soon after the accretion event when sufficient molecular gas agglomerates in
their nuclei.Comment: 16 pages, 1 JPEG figure attached, accepted for publication in ApJ
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