950 research outputs found
Generating Interpretable Fuzzy Controllers using Particle Swarm Optimization and Genetic Programming
Autonomously training interpretable control strategies, called policies,
using pre-existing plant trajectory data is of great interest in industrial
applications. Fuzzy controllers have been used in industry for decades as
interpretable and efficient system controllers. In this study, we introduce a
fuzzy genetic programming (GP) approach called fuzzy GP reinforcement learning
(FGPRL) that can select the relevant state features, determine the size of the
required fuzzy rule set, and automatically adjust all the controller parameters
simultaneously. Each GP individual's fitness is computed using model-based
batch reinforcement learning (RL), which first trains a model using available
system samples and subsequently performs Monte Carlo rollouts to predict each
policy candidate's performance. We compare FGPRL to an extended version of a
related method called fuzzy particle swarm reinforcement learning (FPSRL),
which uses swarm intelligence to tune the fuzzy policy parameters. Experiments
using an industrial benchmark show that FGPRL is able to autonomously learn
interpretable fuzzy policies with high control performance.Comment: Accepted at Genetic and Evolutionary Computation Conference 2018
(GECCO '18
The D-pi-property on products of pi-decomposable groups
[EN] The aim of this paper is to prove the following result: Let pi be a set of odd primes. If the group G = AB is the product of two p-decomposable subgroups A = A(pi) x A(pi') and B = B-pi x B-pi', then G has a unique conjugacy class of Hall pi-subgroups, and any p-subgroup is contained in a Hall pi-subgroup (i.e. G satisfies property D-pi)Research supported by Proyectos PROMETEO/2017/057 from the Generalitat Valenciana (Valencian Community, Spain), and PGC2018-096872-B-I00 from the Ministerio de Ciencia, Innovacion y Universidades, Spain, and FEDER, European Union; and second author also by Project VIP-008 of Yaroslavl P. Demidov State University.Kazarin, L.; MartÃnez-Pastor, A.; Pérez-Ramos, MD. (2020). The D-pi-property on products of pi-decomposable groups. Revista de la Real Academia de Ciencias Exactas FÃsicas y Naturales Serie A Matemáticas. 115(1):1-18. https://doi.org/10.1007/s13398-020-00950-z118115
Coping with salinity in irrigated agriculture: crop evapotranspiration and water management issues
ReviewSoil and water salinity and associated problems are a major challenge for global food production. Strategies to
cope with salinity include a better understanding of the impacts of temporal and spatial dynamics of salinity on
soil water balances vis-Ã -vis evapotranspiration (ET) and devising optimal irrigation schedules and efficient
methods. Both steady state and transient models are now available for predicting salinity effects on reduction of
crop growth and means for its optimization. This paper presents a brief review on the different approaches
available, focusing on the FAO56 framework for coping with the effects of soil salinity on crop ET and yields. The
FAO56 approach, applied widely in soil water balance models, is commonly used to compute water requirements,
including leaching needs. It adopts a daily stress coefficient (Ks) representing both water and salt stresses
to adjust the crop coefficient (Kc) when it is multiplied by the grass reference ETo to obtain the actual crop ET
values for saline environments (ETc act=Ks Kc ETo). The same concept is also applied to the dual Kc approach,
with Ks used to adjust the basal crop coefficient (Kcb). A review on applications of Ks is presented showing that
the FAO56 approach may play an interesting role in water balance computations aimed at supporting irrigation
scheduling. Transient state models, through alternative formulations, provide additional solutions for quantification
of the salinity build-up in the root zone. These include irrigation-induced salinity, upward movement of
salts from saline ground water-table, and sodification processes. Regardless of the approach, these models are
now very much capable of supporting irrigation water management in saline stress conditions. For maintaining
crop growth under salinity environments, soil-crop-water management interventions consistent with site-specific
conditions are then discussed. Adequateness of irrigation methods, cyclic uses of multi-salinity waters and
proper irrigation scheduling are further analyzed as examples of efficient means to obviate the effects of salinityinfo:eu-repo/semantics/publishedVersio
Development of ternary diagrams for estimating water retention properties using geostatistical approaches
Most pedotransfer functions (PTFs) have adopted soil texture information as the main predictor to estimate
soil hydraulic properties, whether inputs are defined in terms of the relative proportion of different grain size
particles or texture-based classifications. The objective of this studywas to develop ternary diagrams for estimating
soil water retention (θ) at−33 and−1500 kPa matric potentials, corresponding to the field capacity and wilting
point, respectively, from particle size distribution using two geostatistical approaches. The texture triangle was
divided into a 1% grid of soil texture composition resulting in 4332 different soil textures. Measured soil water
retention values determined in 742 soil horizons/layers located in Portugal were then used to develop and
validate the hydraulic ternary diagrams. The development subset included two-thirds of the data, and the
validation subset the remaining samples. The measured soil water content values were displayed in the ternary
diagram according to the coordinates given by the particles size distribution determined in the same soil
samples. The volumetric water content values were then predicted for the entire ternary diagram using two
different geostatistical interpolation algorithms (ordinary kriging and the empirical best linear unbiased
predictor). Uncertainty analysis resulted in a root mean square error below 0.040 and 0.034 cm3 cm−3 when
comparing the interpolated water contents at −33 and −1500 kPa matric potential values, respectively, with
the measured ones included in the validation dataset. The estimation variance calculated with both methods
was also considered to access the uncertainty of the predictions. The available water content of Portuguese
soils was then derived from θ−33 kPa and θ−1500 kPa ternary diagrams developed with both approaches. The
hydraulic ternary diagrams may thus serve as simplified tools for estimating water retention properties from
particle size distribution and eventually serve as an alternative to the traditional statistical regression and data
mining techniques used to derive PTFsinfo:eu-repo/semantics/publishedVersio
Products of finite connected subgroups
For a non-empty class of groups L, a finite group G = AB is said to be an L-connected product of the subgroups A and B if e L for all a e A and b e B. In a previous paper, we prove that, for such a product, when L = S is the class of finite soluble groups, then [A, B] is soluble. This generalizes the theorem of Thompson that states the solubility of finite groups whose two-generated subgroups are soluble. In the present paper, our result is applied to extend to finite groups previous research about finite groups in the soluble universe. In particular, we characterize connected products for relevant classes of groups, among others, the class of metanilpotent groups and the class of groups with nilpotent derived subgroup. Additionally, we give local descriptions of relevant subgroups of finite groups
Crop water requirements and crop coefficients for jute mallow (Corchorus olitorius L.) using the SIMDualKc model and assessing irrigation strategies for the Syrian Akkar region
Jute mallow (Corchorus olitorius L.) is an annual crop grown for human consumption of its nutritious leaves in
many regions of the world. Despite its importance for household food security and farmers’ income, reliable
information on the crop’s water requirements is still quite scarce. To overcome this knowledge gap, the irrigation
needs of jute mallow grown in the Akkar region in Syria were investigated. The analysis focused on a three-year
period (2017–2019) where the SIMDualKc model was calibrated and validated for simulating soil water contents
and computing the soil water balance in jute mallow plots irrigated with basin and drip methods. The model was
further used to determine the probabilities of the demand for irrigation water in scenarios considering different
crop season lengths, irrigation methods, and application depths over a longer period of 23 years (1998–2020).
The SIMDualKc model was able to simulate soil water contents measured in the field plots, returning root mean
square error values lower than 0.001 m3 m-3 and modeling efficiencies ranging from 0.358 to 0.812. The calibrated
basal (non-stressed) crop coefficients (Kcb) were 0.15, 0.95, and 0.95 for the initial (Kcb ini), mid-season
(Kcb mid), and end-season (Kcb end) stages, respectively. The crop was harvested twice per season, with the drip
treatments presenting the highest water productivity and economic indicators. In contrast, the basin treatment
resulted in substantial percolation losses, which affected yields and indicators. Although net irrigation requirements
showed a large variation for the extremes of the long-term weather time series, differences between
the years representing average water demand and those representing very high water demand were only found
for the drip irrigation scenarios. This study contributes to improving irrigation water management of jute mallow
in the Syrian Akkar region, and for the sustainability of local production systemsinfo:eu-repo/semantics/publishedVersio
Proton-neutron quadrupole interactions: an effective contribution to the pairing field
We point out that the proton-neutron energy contribution, for low multipoles
(in particular for the quadrupole component), effectively renormalizes the
strength of the pairing interaction acting amongst identical nucleons filling
up a single-j or a set of degenerate many-j shells. We carry out the
calculation in lowest-order perturbation theory. We perform a study of this
correction in various mass regions. These results may have implications for the
use of pairing theory in medium-heavy nuclei and for the study of pairing
energy corrections to the liquid drop model when studying nuclear masses.Comment: 19 pages, TeX, 3 tables, 2 figures. Accepted in PR
Pathogenicity Levels of Colombian Strains of Candida auris and Brazilian Strains of Candida haemulonii Species Complex in Both Murine and Galleria mellonella Experimental Models
Candida auris and Candida haemulonii complex (C. haemulonii, C. haemulonii var. vulnera and C. duobushaemulonii) are phylogenetically related species that share some physiological features and habits. In the present study, we compared the virulence of these yeast species using two different experimental models: (i) Galleria mellonella larvae to evaluate the survival rate, fungal burden, histopathology and phagocytosis index and (ii) BALB/c mice to evaluate the survival. In addition, the fungal capacity to form biofilm over an inert surface was analyzed. Our results showed that in both experimental models, the animal survival rate was lower when infected with C. auris strains than the C. haemulonii species complex. The hemocytes of G. mellonella showed a significantly reduced ability to phagocytize the most virulent strains forming the C. haemulonii species complex. Interestingly, for C. auris, it was impossible to measure the phagocytosis index due to a general lysis of the hemocytes. Moreover, it was observed a greater capability of biofilm formation by C. auris compared to C. haemulonii species complex. In conclusion, we observed that C. auris and C. haemulonii complex have different levels of pathogenicity in the experimental models employed in the present study
Modelling soil water dynamics of full and deficit drip irrigated maize cultivated under a rain shelter
Research PaperThe model HYDRUS-1D was used to simulate soil water dynamics of full and deficit irrigated
maize grown under a rainout shelter during two crop seasons. Four irrigation treatments
were established based on the amount of water applied to fulfil crop water requirements.
Treatment D1 was irrigated to fully satisfy crop water requirements, while treatments D2
(mild deficit), D3 (moderate deficit), and D4 (severe deficit) were for increased controlled
water stress conditions. The computation and partitioning of evapotranspiration data into
soil evaporation and crop transpiration was carried out with the SIMDualKc model, and then
used with HYDRUS-1D. The soil hydraulic properties were determined from numerical
inversion of field water content data. The compensated root water uptake mechanism was
used to describe water removal by plants. TheHYDRUS-1D model successfully simulated the
temporal variability of soil water dynamics in treatments irrigated with full and deficit irrigation,
producing RMSE values that varied between 0.014 and 0.025 cm3 cm 3 when
comparing model simulations with field measurements. Actual transpiration varied between
224 and 483 mm. Potential transpiration reductions varied from 0.4 to 48.8% due to
water stress, but plants were able to compensate for the water deficits in the surface layers by
removing more water from the deeper, less stressed layers. HYDRUS-1D water balance estimates
were also comparable with the corresponding ones determined with the SIMDualKc
water balance model. Both modelling approaches should contribute to improve the webbased
IRRIGA system, used to support farm irrigation scheduling in Brazilinfo:eu-repo/semantics/publishedVersio
A Survey on Sylow Normalizers and Classes of Groups
We report on a stream of research in relation with Sylow normalizers,
i.e. normalizers of Sylow subgroups, of finite groups and group’s classes.D'aniello, A.; Kazarin, L.; MartÃnez Pastor, A.; Perez Ramos, MD. (2014). A Survey on Sylow Normalizers and Classes of Groups. Applied Mathematical Sciences. 8(134):6745-6752. doi:10.12988/ams.2014.49689S67456752813
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