9,688 research outputs found
Kardar-Parisi-Zhang growth on one-dimensional decreasing substrates
Recent experimental works on one-dimensional (1D) circular
Kardar-Parisi-Zhang (KPZ) systems whose radii decrease in time have reported
controversial conclusions about the statistics of their interfaces. Motivated
by this, we investigate here several 1D KPZ models on substrates whose size
changes in time as , focusing on the case . From
extensive numerical simulations, we show that for there exists a
transient regime in which the statistics is consistent with that of flat KPZ
systems (the case), for both . Actually,
for a given model, and , we observe that a difference between
ingrowing () systems arises only at long
times (), when the expanding surfaces cross over to
the statistics of curved KPZ systems, whereas the shrinking ones become
completely correlated. A generalization of the Family-Vicsek scaling for the
roughness of ingrowing interfaces is presented. Our results demonstrate that a
transient flat statistics is a general feature of systems starting with large
initial sizes, regardless their curvature. This is consistent with their recent
observation in ingrowing turbulent liquid crystal interfaces, but it is in
contrast with the apparent observation of curved statistics in colloidal
deposition at the edge of evaporating drops. A possible explanation for this
last result, as a consequence of the very small number of monolayers analyzed
in this experiment, is given. This is illustrated in a competitive growth model
presenting a few-monolayer transient and an asymptotic behavior consistent,
respectively, with the curved and flat statistics.Comment: 5 pages, 3 figure
Width and extremal height distributions of fluctuating interfaces with window boundary conditions
We present a detailed study of squared local roughness (SLRDs) and local
extremal height distributions (LEHDs), calculated in windows of lateral size
, for interfaces in several universality classes, in substrate dimensions
and . We show that their cumulants follow a Family-Vicsek
type scaling, and, at early times, when ( is the correlation
length), the rescaled SLRDs are given by log-normal distributions, with their
th cumulant scaling as . This give rise to an
interesting temporal scaling for such cumulants , with . This scaling is analytically
proved for the Edwards-Wilkinson (EW) and Random Deposition interfaces, and
numerically confirmed for other classes. In general, it is featured by small
corrections and, thus, it yields exponents 's (and, consequently,
, and ) in nice agreement with their respective universality
class. Thus, it is an useful framework for numerical and experimental
investigations, where it is, usually, hard to estimate the dynamic and
mainly the (global) roughness exponents. The stationary (for ) SLRDs and LEHDs of Kardar-Parisi-Zhang (KPZ) class are also investigated
and, for some models, strong finite-size corrections are found. However, we
demonstrate that good evidences of their universality can be obtained through
successive extrapolations of their cumulant ratios for long times and large
's. We also show that SLRDs and LEHDs are the same for flat and curved KPZ
interfaces.Comment: 11 pages, 10 figures, 4 table
Prediction of overwash in alongshore variable barrier islands [Previsão da ocorrência de galgamentos em ilhas barreira com variabilidade longilitoral]
Overwash prediction is very important for coastal zone
management. This work intends to identify alongshore variations in
storm impact and evaluate the role of sub-aerial and submerged
morphologies in overwash occurrence. For this study, 24 cross-shore
topo-bathymetric profiles were set on Barreta Island (Ria Formosa
barrier island system, Portugal). Pre- and post-overwash surveys were
made between August 2012 and April 2013. During overwash events,
tidal levels and wave parameters at breaking were obtained. Overwash
occurred under storm and non-storm conditions, the latter coincident
with spring high-tide. Beach morphology was spatially variable, and
changeable from one overwash episode to the next. Predictions of
overwash occurrence were made using the Overwash Potential, defined
as the difference between runup and barrier elevation. Several runup
equations were tested, and the results compared to the actual
observations. The selected predictor provided an accuracy of 88% for
the identification of the locations where overwash occurred. This study
proves that nearshore and foreshore morphologies have a major impact
on the longshore distribution of overwash.info:eu-repo/semantics/publishedVersio
Big Data on Decision Making in Energetic Management of Copper Mining
Indexado en: Web of Science; Scopus.It is proposed an analysis of the related variables with the energetic consumption in the process of concentrate of copper; specifically ball mills and SAG. The methodology considers the analysis of great volumes of data, which allows to identify the variables of interest (tonnage, temperature and power) to reach to an improvement plan in the energetic efficiency. The correct processing of the great volumen of data, previous imputation to the null data, not informed and out of range, coming from the milling process of copper, a decision support systems integrated, it allows to obtain clear and on line information for the decision making. As results it is establish that exist correlation between the energetic consumption of the Ball and SAG Mills, regarding the East, West temperature and winding. Nevertheless, it is not observed correlation between the energetic consumption of the Ball Mills and the SAG Mills, regarding to the tonnages of feed of SAG Mill. In consequence, From the experimental design, a similarity of behavior between two groups of different mills was determined in lines process. In addition, it was determined that there is a difference in energy consumption between the mills of the same group. This approach modifies the method presented in [1].(a)http://www.univagora.ro/jour/index.php/ijccc/article/view/2784/106
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