This paper presents an effective approach to identify power quality (PQ) events based on IEEE Std 1159-2009 caused by intermittent power sources like those of renewable energy. An efficient ...characterization of these disturbances is granted by the use of two useful wavelet-based indices. For this purpose, a wavelet-based global disturbance ratio (GDR) index, defined through its instantaneous precursor instantaneous transient disturbance ITD(t) index, is used in power distribution networks (PDNs) under steady-state and/or transient conditions. An intelligent disturbance classification is done using a support vector machine (SVM) with a minimum input vector based on the GDR index. The effectiveness of the proposed technique is validated using a real-time experimental system with single event and multi-event signals.
Unplanned hospital readmissions mean a significant burden for health systems. Accurately estimating the patient’s readmission risk could help to optimise the discharge decision-making process by ...smartly ordering patients based on a severity score, thus helping to improve the usage of clinical resources. A great number of heterogeneous factors can influence the readmission risk, which makes it highly difficult to be estimated by a human agent. However, this score could be achieved with the help of AI models, acting as aiding tools for decision support systems. In this paper, we propose a machine learning classification and risk stratification approach to assess the readmission problem and provide a decision support system based on estimated patient risk scores.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
BasisGen is a Python package for the automatic generation of bases of operators in effective field theories. It accepts any semisimple symmetry group and fields in any of its finite dimensional ...irreducible representations. It takes into account integration by parts redundancy and, optionally, the use of equations of motion. The implementation is based on well-known methods to generate and decompose representations using roots and weights, which allow for fast calculations, even with large numbers of fields and high-dimensional operators. BasisGen can also be used to do some representation-theoretic operations, such as finding the weight system of an irreducible representation from its highest weight or decomposing a tensor product of representations.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Computational thinking (CT) is being located at the focus of educational innovation, as a set of problem-solving skills that must be acquired by the new generations of students to thrive in a digital ...world full of objects driven by software. However, there is still no consensus on a CT definition or how to measure it. In response, we attempt to address both issues from a psychometric approach. On the one hand, a Computational Thinking Test (CTt) is administered on a sample of 1,251 Spanish students from 5th to 10th grade, so its descriptive statistics and reliability are reported in this paper. On the second hand, the criterion validity of the CTt is studied with respect to other standardized psychological tests: the Primary Mental Abilities (PMA) battery, and the RP30 problem-solving test. Thus, it is intended to provide a new instrument for CT measurement and additionally give evidence of the nature of CT through its associations with key related psychological constructs. Results show statistically significant correlations at least moderately intense between CT and: spatial ability (r = 0.44), reasoning ability (r = 0.44), and problem-solving ability (r = 0.67). These results are consistent with recent theoretical proposals linking CT to some components of the Cattel-Horn-Carroll (CHC) model of intelligence, and corroborate the conceptualization of CT as a problem-solving ability.
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•A Computational Thinking Test (CTt) aimed at Grades 5th to 10th is provided•Computational thinking correlates moderately with spatial and reasoning abilities•Computational thinking correlates strongly with problem-solving ability•Results are consistent with proposals linking CT with the CHC model of intelligence•Gender differences in computational thinking performance are discussed
Networks have become increasingly important to model complex systems composed of interacting elements. Network data mining has a large number of applications in many disciplines including ...protein-protein interaction networks, social networks, transportation networks, and telecommunication networks. Different empirical studies have shown that it is possible to predict new relationships between elements attending to the topology of the network and the properties of its elements. The problem of predicting new relationships in networks is called link prediction. Link prediction aims to infer the behavior of the network link formation process by predicting missed or future relationships based on currently observed connections. It has become an attractive area of study since it allows us to predict how networks will evolve. In this survey, we will review the general-purpose techniques at the heart of the link prediction problem, which can be complemented by domain-specific heuristic methods in practice.
Heterogeneous photocatalysis has become a comprehensively studied area of research during the past three decades due to its practical interest in applications including water-air depollution, cancer ...therapy, sterilization, artificial photosynthesis (CO
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photoreduction), anti-fogging surfaces, heat transfer and heat dissipation, anticorrosion, lithography, photochromism, solar chemicals production and many others. The utilization of solar irradiation to supply energy or to initiate chemical reactions is already an established idea. Excited electron-hole pairs are generated upon light irradiation of a wide-band gap semiconductor which can be applied to solar cells to generate electricity or in chemical processes to create/degrade specific compounds. While the field of heterogeneous photocatalysis for pollutant abatement and mineralisation of contaminants has been extensively investigated, a new research avenue related to the selective valorisation of residues has recently emerged as a promising alternative to utilise solar light for the production of valuable chemicals and fuels. This tutorial review will focus on the potential and applications of solid photonanocatalysts for the selective transformation of biomass-derived substrates.
Photocatalytic reactions under milder conditions to those generally present in thermal processes can facilitate the design of short and efficient reaction sequences, minimizing side processes and making use of sunlight as a completely renewable source of energy. Photocatalysis has a significant potential for the conversion of lignocellulosics to valuable products.
We analyze a modular invariant model of lepton masses, with neutrino masses originating either from the Weinberg operator or from the seesaw. The constraint provided by modular invariance is so ...strong that neutrino mass ratios, lepton mixing angles and Dirac/Majorana phases do not depend on any Lagrangian parameter. They only depend on the vacuum of the theory, parametrized in terms of a complex modulus and a real field. Thus eight measurable quantities are described by the three vacuum parameters, whose optimization provides an excellent fit to data for the Weinberg operator and a good fit for the seesaw case. Neutrino masses from the Weinberg operator (seesaw) have inverted (normal) ordering. Several sources of potential corrections, such as higher dimensional operators, renormalization group evolution and supersymmetry breaking effects, are carefully discussed and shown not to affect the predictions under reasonable conditions.
Moiré patterns at van der Waals interfaces between twisted 2D crystals give rise to distinct optoelectronic excitations, as well as, narrowly dispersive bands responsible for correlated electron ...phenomena. Contrasting with the conventional, mechanically stacked planar twist moirés, recent work shows twisted van der Waals interfaces spontaneously formed in nanowires of layered crystals, where Eshelby twist due to axial screw dislocations stabilizes a chiral structure with small interlayer rotation. Here, the realization of tunable twist in germanium(II) sulfide (GeS) van der Waals nanowires is reported. Tapered nanowires host continuously variable interlayer twist. Homojunctions between dislocated (chiral) and defect‐free (achiral) segments are obtained by triggering the emission of axial dislocations during growth. Measurements across such junctions, implemented here using local absorption and luminescence spectroscopy, provide a convenient tool for detecting twist effects. The results identify a versatile system for 3D twistronics, probing moiré physics, and for realizing moiré architectures without equivalent in planar systems.
Eshelby twist in van der Waals nanowires creates twisted interfaces and associated moiré patterns that modulate the electronic structure and can cause correlated electron phenomena. Here, twist manipulation is demonstrated by realizing nanowires harboring continuously varying interlayer moirés and homojunctions connecting twisted and equilibrium‐stacked segments. These novel architectures provide versatile platforms for exploring twist effects in van der Waals crystals.
The utility of induced pluripotent stem (iPS) cells for investigating the molecular logic of pluripotency and for eventual clinical application is limited by the low efficiency of current methods for ...reprogramming. Here we show that reprogramming of juvenile human primary keratinocytes by retroviral transduction with OCT4, SOX2, KLF4 and c-MYC is at least 100-fold more efficient and twofold faster compared with reprogramming of human fibroblasts. Keratinocyte-derived iPS (KiPS) cells appear indistinguishable from human embryonic stem cells in colony morphology, growth properties, expression of pluripotency-associated transcription factors and surface markers, global gene expression profiles and differentiation potential in vitro and in vivo. To underscore the efficiency and practicability of this technology, we generated KiPS cells from single adult human hairs. Our findings provide an experimental model for investigating the bases of cellular reprogramming and highlight potential advantages of using keratinocytes to generate patient-specific iPS cells.
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Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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