9,079 research outputs found
Pressure sensor placement for leak localization using simulated annealing with hyperparameter optimization
© 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksThis paper presents a machine learning method for optimal pressure sensor placement in water distribution networks. The proposed approach considers annealing meta-heuristics, and it is focused on the optimal placement of the sensors to perform leak localization. Unlike other works, this method considers a limited number of sensors to be placed and some restrictions on critical nodes that can be excluded or preselected. The approach is based on minimizing a cost function; this cost function is assigned as the leak location error, which varies depending on the subset of nodes where the sensors are assigned and the configuration of the leak location method. A leak localization technique based on k-NN classifiers was used, and during the minimization of the cost function, classifier hyperparameters were simultaneously optimized. The proposed method was tested on the Hanoi water distribution network programmed in MATLAB.Postprint (author's final draft
AquaData and AquaGIS: Two computer utilities for temporal and spatial simulations of water-limited yield with AquaCrop.
The crop simulation model AquaCrop, recently developed by FAO can be used for a wide range of purposes. However, in its present form, its use over large areas or for applications that require a large number of simulations runs (e.g., long-term analysis), is not practical without developing software to facilitate such applications. Two tools for managing the inputs and outputs of AquaCrop, named AquaData and AquaGIS, have been developed for this purpose and are presented here. Both software utilities have been programmed in Delphi v. 5 and in addition, AquaGIS requires the Geographic Information System (GIS) programming tool MapObjects. These utilities allow the efficient management of input and output files, along with a GIS module to develop spatial analysis and effect spatial visualization of the results, facilitating knowledge dissemination. A sample of application of the utilities is given here, as an AquaCrop simulation analysis of impact of climate change on wheat yield in Southern Spain, which requires extensive input data preparation and output processing. The use of AquaCrop without the two utilities would have required approximately 1000 h of work, while the utilization of AquaData and AquaGIS reduced that time by more than 99%. Furthermore, the use of GIS, made it possible to perform a spatial analysis of the results, thus providing a new option to extend the use of the AquaCrop model to scales requiring spatial and temporal analyses
Effect of the forest-mine boundary form on woody colonization and forest expansion in degraded ecosystems
[ENG]We evaluated the ecological significance of the boundary form between two patches
with contrasting vegetation (mine grassland and adjacent forest) on woody colonization and forest
expansion in open-cast coal mines in Northern Spain. Woody colonization and browsing traces
were measured on three mine sites, along 24 transects that were laid out perpendicular to the
forest-mine boundary and classified according to their shape (concave, convex, straight). Mine sites
were colonized from the close forest by woody species, whose colonization intensity depends on
the boundary form. The overall colonization intensity decreased with increasing distance to the
forest and differed depending on the boundary form. The more intense colonization was found in
concave boundaries and the strongest decrease in convex boundaries close to the forest, whereas
straight boundaries showed an intermediate colonization pattern. Concave boundaries reached
higher woody cover in the basal strata of the mines than convex (up to 2 m) or straight boundaries
(up to 1 m) from 11 m to the forest edge, mainly by the presence of dense patches of Cytisus scoparius
(L.) Link, with a scattered overstory of Genista florida L. These shrubs might reduce the browsing
intensity and act as nurse plants facilitating the establishment of Quercus petraea (Matt.) Liebl. in
mine areas at greater distances from the forest edge. The forest-mine boundary form does not affect
the forest vertical structure that is homogenous and does not help explain the woody colonization
pattern in the mines. We conclude that edge characteristics have a strong potential to be used in the
restoration of native forests based on natural processes. The implications of our results for sessile
oak (Quercus petraea (Matt.) Liebl.) forest expansion along edges in fragmented Mediterranean forest
landscapes were discussed
Impact of climate change on irrigation management for olive orchards at southern Spain
The irrigation management for olive orchards under future weather conditions requires the development of advanced
tools for considering specific physiological and phenological components affected by the foreseen changes
in climate and atmospheric [CO2]
Early Science with the Large Millimeter Telescope: an energy-driven wind revealed by massive molecular and fast X-ray outflows in the Seyfert Galaxy IRAS 17020+4544
We report on the coexistence of powerful gas outflows observed in millimeter
and X-ray data of the Radio-Loud Narrow Line Seyfert 1 Galaxy IRAS 17020+4544.
Thanks to the large collecting power of the Large Millimeter Telescope, a
prominent line arising from the 12CO(1-0) transition was revealed in recent
observations of this source. The complex profile is composed by a narrow
double-peak line and a broad wing. While the double-peak structure may be
arising in a disk of molecular material, the broad wing is interpreted as the
signature of a massive outflow of molecular gas with an approximate bulk
velocity of -660 km/s. This molecular wind is likely associated to a
multi-component X-ray Ultra-Fast Outflow with velocities reaching up to ~0.1c
and column densities in the range 10^{21-23.9} cm^-2 that was reported in the
source prior to the LMT observations. The momentum load estimated in the two
gas phases indicates that within the observational uncertainties the outflow is
consistent with being propagating through the galaxy and sweeping up the gas
while conserving its energy. This scenario, which has been often postulated as
a viable mechanism of how AGN feedback takes place, has so far been observed
only in ULIRGs sources. IRAS 17020+4544 with bolometric and infrared luminosity
respectively of 5X10^{44} erg/s and 1.05X10^{11} L_sun appears to be an example
of AGN feedback in a NLSy1 Galaxy (a low power AGN). New proprietary
multi-wavelength data recently obtained on this source will allow us to
corroborate the proposed hypothesis.Comment: Accepted for publication on ApJ Letters, 9 pages, 4 figure
Effects of ammonium nitrate, cesium chloride and tetraethylammonium on high-affinity potassium uptake in habanero pepper plantlets (Capsicum chinense Jacq.)
Potassium (K+) is an essential nutrient and the most abundant cation in plant cells. Plants have a wide variety of transport systems for K+ acquisition that catalyze K+ uptake across a wide spectrum of external K+ concentrations and mediate K+ movement within the plant, as well as its release into the environment. The KUP/HAK/KT transporter family plays a key role in K+ homeostasis in plant cells. The present study demonstrates that habanero pepper plantlets have a clear pattern of K+ uptake when resupplemented with K+ after K+ starvation. Habanero pepper plantlets, re-supplemented with a solution containing low concentrations of K+ after 72, 96 or 120 h of K+ starvation were able to decrease the amount of K+ in the solution at different time points. To study the effect of NH4+, we added different concentrations of NH4NO3 to the medium solution and demonstrated that NH4+ inhibited K+ uptake in a dose-dependent manner. When the plantlets were subjected to K+ starvation for 72 h and then resupplemented with 50 or 100 ÎĽM K+, exposure to K+ channel blockers (10 mM CsCl and 20 mM TEA) decreased their K+ uptake compared with the control treatment. A model demonstrating the process of K+ uptake through an NH4+-insensitive component was proposed.Key words: Potassium, high affinity transporters, channel blockers, ammonium
SeparaciĂłn de aceitunas sobremaduras y alambradas en lĂnea mediante rebote
La fermentaciĂłn tradicional de aceitunas de mesa da lugar a la apariciĂłn de distintos tipos de defectos: alambrado, compactado y sobremaduraciĂłn. En este estudio se han ensayado varios lotes que incluyen aceitunas sanas y defectuosas, caracterizándolas objetivamente por color, dureza y densidad. Se ha diseñado asimismo un dispositivo en lĂnea consistente en un cilindro rotativo recubierto con un material amortiguador. Este elemento permite separar correctamente el 95% de las aceitunas blandas (alambradas y sobremaduras) respecto a las sanas. Las aceitunas compactas pueden separarse mediante densidad. En este artĂculo se presentan los resultados de un trabajo que será expuesto en el II Congreso Nacional de AgrolngenierĂa 2003 (CĂłrdoba
Effect of the mother tree age and acorn weight in the regenerative characteristics of Quercus faginea
[EN] The establishment of oak trees is often a slow and difficult process. Hence, it is necessary to determine the characteristics that can lead to improving their regeneration. In this genus, seed size is highly variable both at the interspecific and intraspecific
levels, and the effects of intrapopulation variability are not well understood, being even less so for Quercus faginea. In this
study, the effects of the age of the mother tree, seed weight and the interaction between these two factors on seed germination,
emergence and growth (biomass) were analysed. For this purpose, 16 trees—8 young and 8 old—were selected with the intent
to cover the entire range of acorn weights produced in this population. Among the main results, it should be noted that: (1)
in older trees, it is easier to find larger acorns; (2) the percentage and the speed of germination of the acorns of young trees
is greater than that of old trees; (3) the percentage and the speed of seedling emergence of young trees is greater than that
of old trees; and (4) cotyledon weight is the variable that most influences biomass, quite often in a positive way. Therefore,
maintaining intrapopulation variability seems to be an approach that most favours the persistence of these populations
Hepatitis C virus infection in blood donors from the state of Puebla, Mexico
<p>Abstract</p> <p>Background</p> <p>Worldwide, 130 million persons are estimated to be infected with HCV. Puebla is the Mexican state with the highest mortality due to hepatic cirrhosis. Therefore, it is imperative to obtain epidemiological data on HCV infection in asymptomatic people of this region. The objective of present study was to analyze the prevalence of antibodies and genotypes of hepatitis C virus (HCV) in blood donors from Puebla, Mexico.</p> <p>Results</p> <p>The overall prevalence was 0.84% (515/61553). Distribution by region was: North, 0.86% (54/6270); Southeast, 1.04% (75/7197); Southwest, 0.93% (36/3852); and Central, 0.79% (350/44234). Ninety-six donors were enrolled for detection and genotyping of virus, from which 37 (38.5%) were HCV-RNA positive. Detected subtypes were: 1a (40.5%), 1b (27.0%), mixed 1a/1b (18.9%), undetermined genotype 1 (5.4%), 2a (2.7%), 2b (2.7%), and mixed 1a/2a (2.7%). All recovered donors with S/CO > 39 were HCV-RNA positive (11/11) and presented elevated ALT; in donors with S/CO < 39 HCV-RNA, positivity was of 30.4%; and 70% had normal values of ALT. The main risk factors associated with HCV infection were blood transfusion and surgery.</p> <p>Conclusions</p> <p>HCV prevalence of donors in Puebla is similar to other Mexican states. The most prevalent genotype is 1, of which subtype 1a is the most frequent.</p
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