4,897 research outputs found
Initial pseudo-steady state & asymptotic KPZ universality in semiconductor on polymer deposition
The Kardar-Parisi-Zhang (KPZ) class is a paradigmatic example of universality
in nonequilibrium phenomena, but clear experimental evidences of asymptotic
2D-KPZ statistics are still very rare, and far less understanding stems from
its short-time behavior. We tackle such issues by analyzing surface
fluctuations of CdTe films deposited on polymeric substrates, based on a huge
spatio-temporal surface sampling acquired through atomic force microscopy. A
\textit{pseudo}-steady state (where average surface roughness and spatial
correlations stay constant in time) is observed at initial times, persisting up
to deposition of monolayers. This state results from a fine
balance between roughening and smoothening, as supported by a phenomenological
growth model. KPZ statistics arises at long times, thoroughly verified by
universal exponents, spatial covariance and several distributions. Recent
theoretical generalizations of the Family-Vicsek scaling and the emergence of
log-normal distributions during interface growth are experimentally confirmed.
These results confirm that high vacuum vapor deposition of CdTe constitutes a
genuine 2D-KPZ system, and expand our knowledge about possible
substrate-induced short-time behaviors.Comment: 13 pages, 8 figures, 2 table
Measurements relationship among compost bedded pack barn farms in six European countries during the winter and spring season
A new analysis of the GJ581 extrasolar planetary system
We have done a new analysis of the available observations for the GJ581
exoplanetary system. Today this system is controversial due to choices that can
be done in the orbital determination. The main ones are the ocurrence of
aliases and the additional bodies - the planets f and g - announced in Vogt et
al. 2010. Any dynamical study of exoplanets requires the good knowledge of the
orbital elements and the investigations involving the planet g are particularly
interesting, since this body would lie in the Habitable Zone (HZ) of the star
GJ581. This region,for this system, is very attractive of the dynamical point
of view due to several resonances of two and three bodies present there. In
this work, we investigate the conditions under which the planet g may exist. We
stress the fact that the planet g is intimately related with the orbital
elements of the planet d; more precisely, we conclude that it is not possible
to disconnect its existence from the determination of the eccentricity of the
planet d. Concerning the planet f, we have found one solution with period
days, but we are judicious about any affirmation concernig this
body because its signal is in the threshold of detection and the high period is
in a spectral region where the ocorruence of aliases is very common. Besides,
we outline some dynamical features of the habitable zone with the dynamical map
and point out the role played by some resonances laying there.Comment: 12 pages, 9 figure
Building performance analysis of a dairy factory in South Iraq: appraisal of a local bio-based envelope
Received: February 4th, 2021 ; Accepted: April 24th, 2021 ; Published: April 29th, 2021 ; Correspondence: [email protected] have a relevant impact on the environment, and building materials cause
environmental impacts during all life cycle stages: production, utilization, management and
demolition. The global request for more efficient buildings with less environmental impacts has
grown during the last years. Among various technologies, thermal insulation has proven to be
helpful in reducing emissions by increasing energy conservation. This paper intends to show how
the Building Performance Analysis (BPA) supports the decision-making process in many areas
where common insulation materials are not available and there is a general reluctance to use local
natural materials. A building located in the city of Al Chubaish in Dhi Qar Province in Iraq is
examined as a case study. The construction is designed for processing buffalo milk. It was built
in the first decade of the century, during the Iraqi conflict, using only the materials available at
that time, most of which, concrete bricks, mortar and plaster. Currently, this dairy factory is a
very inefficient structure in terms of energy saving. But because its elementary form, it is a perfect
example to investigate how a simple exterior wall insulation can improve building performance
in extreme environmental conditions. Accordingly, two different models have been created. One
is the replica of the real building without any upgrading. The second instead presents a thermal
insulation realized with reed bio-based material locally available. Through advanced simulation
engines and building performance analysis data integrated into Autodesk Revit, each model has
been tested to identify significant improvements in terms of energy savings in this particular
stressed background
Experimental Observation of Quantum Correlations in Modular Variables
We experimentally detect entanglement in modular position and momentum
variables of photon pairs which have passed through -slit apertures. We
first employ an entanglement criteria recently proposed in [Phys. Rev. Lett.
{\bf 106}, 210501 (2011)], using variances of the modular variables. We then
propose an entanglement witness for modular variables based on the Shannon
entropy, and test it experimentally. Finally, we derive criteria for
Einstein-Podolsky-Rosen-Steering correlations using variances and entropy
functions. In both cases, the entropic criteria are more successful at
identifying quantum correlations in our data.Comment: 7 pages, 4 figures, comments welcom
Evaluation of the physical properties of bedding materials for dairy cattle using fuzzy clustering analysis
Changes muscle gene expression profile in Bos indicus cows submitted to medium and high gain rates during recovery from undernutrition
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