<inline-formula><tex-math notation="LaTeX">AC</tex-math></inline-formula> power filters play an important role in limiting the high-frequency current harmonics injected by grid-tied voltage source ...converters (VSCs). Amongst the various types of filters, <inline-formula><tex-math notation="LaTeX">LCL</tex-math></inline-formula> filters with integrated <inline-formula><tex-math notation="LaTeX">LC</tex-math></inline-formula> traps have become popular due to their ability to achieve a size reduction of the grid side inductor while demonstrating a similar current harmonic mitigation performance as a traditional <inline-formula><tex-math notation="LaTeX">LCL</tex-math></inline-formula> filter. In this article, a passively damped filter network with a partially rated <inline-formula><tex-math notation="LaTeX">LC</tex-math></inline-formula> trap (also referred to as the <inline-formula><tex-math notation="LaTeX">L\text{-}PT\text{-}L</tex-math></inline-formula> filter) is proposed and delineated. The proposed <inline-formula><tex-math notation="LaTeX">L\text{-}PT\text{-}L</tex-math></inline-formula> filter provides a <inline-formula><tex-math notation="LaTeX">-60\;\text{dB/dec}</tex-math></inline-formula> roll-off characteristics at frequencies greater than switching frequency. Additionally, it is also demonstrated that this proposed <inline-formula><tex-math notation="LaTeX">L\text{-}PT\text{-}L</tex-math></inline-formula> filter has smaller voltage ratings for two of its shunt-connected capacitor components due to the specific placement of the damping resistor. A systematic analysis of the proposed <inline-formula><tex-math notation="LaTeX">L\text{-}PT\text{-}L</tex-math></inline-formula> filter is elucidated to design and select the component parameters. Steady-state and transient experimental results captured from a grid-tied 2-Level, 3<inline-formula><tex-math notation="LaTeX">\phi</tex-math></inline-formula> VSC prototype are provided to validate the grid current harmonic filtering capability, reduced voltage ratings of the two shunt capacitors and passive damping performance of the proposed <inline-formula><tex-math notation="LaTeX">L\text{-}PT\text{-}L</tex-math></inline-formula> filter. The proposed approach can achieve 19% and 36% filter shunt branch volume reduction for low voltage (208 V, 60 Hz) and medium voltage (4.16 kV, 60 Hz) grid-tied inverter systems, respectively, compared to state-of-the-art <inline-formula><tex-math notation="LaTeX">LCL</tex-math></inline-formula> filters with integrated <inline-formula><tex-math notation="LaTeX">LC</tex-math></inline-formula> traps.
Recently, Ji et al. established certain fixed-point results using Mann’s iterative scheme tailored to G b -metric spaces. Stimulated by the notion of the F -contraction introduced by Wardoski, the ...contraction condition of Ji et al. was generalized in this research. Several fixed-point results with Mann’s iterative scheme endowed with F -contractions in G b -metric spaces were proven. One non-trivial example was elaborated to support the main theorem. Moreover, for application purposes, the existence of the solution to an integral equation is provided by using the axioms of the proven result. The obtained results are generalizations of several existing results in the literature. Furthermore, the results of Ji. et al. are the special case of theorems provided in the present research.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The main purpose of the present paper is to introduced the notions of (∈´,∈´∨q´)-UIFSSAs in subtraction BG-algebras. We provide different characterizations and some equivalent conditions of ...(∈´,∈´∨q´)-UIFSSAs in terms of the level subsets of subtraction BG-algebras. It has been revealed that the (q´,q´)-UIFSSA are (∈´,∈´)-UIFSSA but the converse does not hold and an example is provided. We introduced (∈´,∈´∨q´)-UIFSIDs and its some usual properties. In addition, h−1(N˜ς) is (∈´,∈´∨q´)-UIFSID. Moreover, if h−1(N˜ς) are an (∈´,∈´∨q´)-UIFSID, then N˜ς are an (∈´,∈´∨q´)-UIFSID. Finally, we characterize (∈´,∈´∨q´kˇ)-UIFSHID which is a generalization of (∈´,∈´∨q´)-UIFSHID.
The design of new tokamak machines relying on the use of high temperature superconductors (HTS) is promoting the study of HTS properties at the operating conditions required by fusion applications. ...In particular, the interest in the damage induced by neutron irradiation on RE Ba 2 Cu 3 O 7- δ ( RE BCO, RE = Y or lanthanide series), one of the most used family of HTS, has recently risen and several studies have been devoted to radiation hardness tests performed with ion irradiation or fission neutrons. In this work, the effect of neutron irradiation on YBCO films and commercial RE BCO tapes was investigated using, for the first time, neutrons produced by the D-T fusion reaction. The experiment was carried out at ENEA-Frascati Neutron Generator (FNG) where a deuteron beam is accelerated up to 300 keV and directed on a tritiated target to produce a nearly isotropic 14.1 MeV neutron field via the T(d,n)α fusion reaction. Different YBCO films deposited through metal-organic decomposition (MOD) route on single crystals (SrTiO 3 and LaAlO 3 ) and RE BCO commercial tapes, grown by pulsed laser deposition, were irradiated. Samples exposed to three fluences were compared with a maximum neutron fluence of 1.2·10 14 cm −2 . The properties of HTS materials were assessed before and after irradiation by means of different techniques. From these measurements, no significant effect on the considered properties was recognized indicating the robustness of films up to the explored irradiation fluences.
As a critical parameter in evaluating the reliability of a multiprocessor system when processors malfunction, the \boldsymbol <inline-formula><tex-math ...notation="LaTeX">h</tex-math></inline-formula>-extra connectivity (<inline-formula><tex-math notation="LaTeX">h</tex-math></inline-formula>-EC) of a multiprocessor system modeled by a graph <inline-formula><tex-math notation="LaTeX">G</tex-math></inline-formula>, denoted by <inline-formula><tex-math notation="LaTeX">\kappa ^{(h)}_{o}(G)</tex-math></inline-formula>, is an <inline-formula><tex-math notation="LaTeX">h</tex-math></inline-formula>-extra vertex-cut with minimum cardinality. Both of the <inline-formula><tex-math notation="LaTeX">h</tex-math></inline-formula>-extra conditional diagnosability (<inline-formula><tex-math notation="LaTeX">h</tex-math></inline-formula>-ECD) and the <inline-formula><tex-math notation="LaTeX">t/h</tex-math></inline-formula>-diagnosability of the multiprocessor system are vital to tolerate and diagnose faulty processors. These two parameters rely on the resolving of <inline-formula><tex-math notation="LaTeX">h</tex-math></inline-formula>-EC. For the multiprocessor system based on star graph <inline-formula><tex-math notation="LaTeX">S_{n}</tex-math></inline-formula>, we show that the 5-EC <inline-formula><tex-math notation="LaTeX">\kappa ^{(5)}_{o}(S_{n})</tex-math></inline-formula> of <inline-formula><tex-math notation="LaTeX">S_{n}</tex-math></inline-formula> (<inline-formula><tex-math notation="LaTeX">n\geq 5</tex-math></inline-formula>) is <inline-formula><tex-math notation="LaTeX">6n-18</tex-math></inline-formula>. As a by-product, we present a novel proof of <inline-formula><tex-math notation="LaTeX">\kappa ^{(2)}_{o}(S_{n})=3n-7</tex-math></inline-formula> (resp., <inline-formula><tex-math notation="LaTeX">\kappa ^{(4)}_{o}(S_{n})=5n-14</tex-math></inline-formula>) by relaxing the restriction <inline-formula><tex-math notation="LaTeX">n\geq 10</tex-math></inline-formula> (resp., <inline-formula><tex-math notation="LaTeX">n\geq 7</tex-math></inline-formula>) to <inline-formula><tex-math notation="LaTeX">n\geq 5</tex-math></inline-formula> (resp., <inline-formula><tex-math notation="LaTeX">n\geq 5</tex-math></inline-formula>). Furthermore, we determine that the <inline-formula><tex-math notation="LaTeX">h</tex-math></inline-formula>-ECD of <inline-formula><tex-math notation="LaTeX">S_{n}</tex-math></inline-formula> <inline-formula><tex-math notation="LaTeX">(n\geq 5)</tex-math></inline-formula> under the preparata, metze, and chien (PMC) model is <inline-formula><tex-math notation="LaTeX">(h+1)n-2h-1</tex-math></inline-formula> for <inline-formula><tex-math notation="LaTeX">1\leq h\leq 3</tex-math></inline-formula> and <inline-formula><tex-math notation="LaTeX">(h+1)n-3h+2</tex-math></inline-formula> for <inline-formula><tex-math notation="LaTeX">4\leq h\leq 5</tex-math></inline-formula>. In addition, we show that <inline-formula><tex-math notation="LaTeX">S_{n}</tex-math></inline-formula> is <inline-formula><tex-math notation="LaTeX">(h+1)n-4h+2/h</tex-math></inline-formula>-diagnosable for <inline-formula><tex-math notation="LaTeX">4\leq h\leq 5</tex-math></inline-formula>, which extends the result that <inline-formula><tex-math notation="LaTeX">S_{n}</tex-math></inline-formula> is <inline-formula><tex-math notation="LaTeX">(h+1)n-3h-1/h</tex-math></inline-formula>-diagnosable for <inline-formula><tex-math notation="LaTeX">1\leq h\leq 3</tex-math></inline-formula> by Zhou et al. "The t/k-diagnosability of star graph networks," IEEE Trans. Comput. , vol. 64, no. 2, pp. 547-555, Feb. 2015.
Finding a small set of representative tuples from a large database is an important functionality for supporting multi-criteria decision making. Top-<inline-formula><tex-math ...notation="LaTeX">k</tex-math> <mml:math><mml:mi>k</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq2-3166835.gif"/> </inline-formula> queries and skyline queries are two widely studied queries to fulfill this task. However, both of them have some limitations: a top-<inline-formula><tex-math notation="LaTeX">k</tex-math> <mml:math><mml:mi>k</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq3-3166835.gif"/> </inline-formula> query requires the user to provide her utility functions for finding the <inline-formula><tex-math notation="LaTeX">k</tex-math> <mml:math><mml:mi>k</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq4-3166835.gif"/> </inline-formula> tuples with the highest scores as the result; a skyline query does not need any user-specified utility function but cannot control the result size. To overcome their drawbacks, the <inline-formula><tex-math notation="LaTeX">k</tex-math> <mml:math><mml:mi>k</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq5-3166835.gif"/> </inline-formula>-regret minimization query was proposed and received much attention recently, since it does not require any user-specified utility function and returns a fixed-size result set. Specifically, it selects a set <inline-formula><tex-math notation="LaTeX">R</tex-math> <mml:math><mml:mi>R</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq6-3166835.gif"/> </inline-formula> of tuples with a pre-defined size <inline-formula><tex-math notation="LaTeX">r</tex-math> <mml:math><mml:mi>r</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq7-3166835.gif"/> </inline-formula> from a database <inline-formula><tex-math notation="LaTeX">D</tex-math> <mml:math><mml:mi>D</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq8-3166835.gif"/> </inline-formula> such that the maximum <inline-formula><tex-math notation="LaTeX">k</tex-math> <mml:math><mml:mi>k</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq9-3166835.gif"/> </inline-formula>-regret ratio , which captures how well the top-ranked tuple in <inline-formula><tex-math notation="LaTeX">R</tex-math> <mml:math><mml:mi>R</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq10-3166835.gif"/> </inline-formula> represents the top-<inline-formula><tex-math notation="LaTeX">k</tex-math> <mml:math><mml:mi>k</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq11-3166835.gif"/> </inline-formula> tuples in <inline-formula><tex-math notation="LaTeX">D</tex-math> <mml:math><mml:mi>D</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq12-3166835.gif"/> </inline-formula> for any possible utility function, is minimized. Although there have been many methods for <inline-formula><tex-math notation="LaTeX">k</tex-math> <mml:math><mml:mi>k</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq13-3166835.gif"/> </inline-formula>-regret minimization query processing, most of them are designed for static databases without tuple insertions and deletions. The only known algorithm to process continuous <inline-formula><tex-math notation="LaTeX">k</tex-math> <mml:math><mml:mi>k</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq14-3166835.gif"/> </inline-formula>-regret minimization queries (C<inline-formula><tex-math notation="LaTeX">k</tex-math> <mml:math><mml:mi>k</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq15-3166835.gif"/> </inline-formula>RMQ) in dynamic databases suffers from suboptimal approximation and high time complexity. In this paper, we propose a novel dynamic coreset-based approach, called DynCore , for C<inline-formula><tex-math notation="LaTeX">k</tex-math> <mml:math><mml:mi>k</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq16-3166835.gif"/> </inline-formula>RMQ processing. It achieves the same (asymptotically optimal) upper bound on the maximum <inline-formula><tex-math notation="LaTeX">k</tex-math> <mml:math><mml:mi>k</mml:mi></mml:math><inline-graphic xlink:href="wang-ieq17-3166835.gif"/> </inline-formula>-regret ratio as the best-known static algorithm. Meanwhile, its time complexity is sublinear to the database size, which is significantly lower than that of the existing dynamic algorithm. The efficiency and effectiveness of DynCore is confirmed by experimental results on real-world and synthetic datasets.
Z -number is an effective model to describe uncertainty in the real world. Under the condition that uncertainty reasoning is an important issue to process information, how to achieve Z -valuation ...uncertainty reasoning is a problem. As a Z -number involves both fuzzy and probabilistic uncertainty, main difficulty in the problem to be solved is accomplishing both two uncertainties' reasoning. In this paper, a novel Z -network model and its associated reasoning algorithm are proposed to overcome the difficulty. Structure of the proposed Z -network that contains three basic structures is directed acyclic graph, and this is similarly with Bayesian network (BN). Process of reasoning algorithm involves two parts: first, Bayesian reasoning is applied to establish an optimization model for probabilistic uncertainty reasoning in a Z -number; second, the arithmetic approach of discrete Z -number on if-then rule and maximum entropy approach are proposed for fuzzy uncertainty reasoning. Z -network is essentially an extended model on the basis of BN and properties of a Z -number for Z -valuation uncertainty reasoning. In application, a novel framework of dependence assessment in human reliability analysis is proposed based on Z -network, and a case study demonstrates its effectiveness.
Nano-tungsten trioxide (WO 3 ) particles were introduced homogeneously into Bi 1.2 Pb 0.3 Sr 1.54 Ca 2.06 Cu 3 O y (Bi 2223) superconductor matrix by a sol-casting technique and their effect on flux ...pinning properties was studied. To prevent W substitution at a lattice site of the matrix phase, WO 3 nanoparticles were added to processed Bi 2223 powders, which helped to retain transition temperature ( T c ) near 105 K. The magnetic properties were obtained in the temperature ( T ) range of 10 to 77 K and up to 9 T magnetic fields ( B ). The temperature and field dependences of critical current densities ( J c ) and the flux pinning force densities ( F p ) were examined in terms of the possible sources of flux pinning in the samples. The addition of low concentrations (0.1 wt.%) of nano WO 3 led to effective pinning and enhancement of current densities to higher fields, up to 77 K, compared to Bi 2223. Analysis of F p (B) curves showed normal surface pinning at platelet/grain boundary defects to be dominant at low fields at all temperatures, while additional pinning from WO 3 is observed at higher fields. The limiting fields where pinning from different mechanisms vanishes are estimated using scaling laws. Irreversibility fields ( B irr ) estimated from the high field region of F p (B) curves suggest that substantial pinning is caused by nano WO 3 addition to Bi 2223.
Support vector machines (SVM) have drawn wide attention for the last two decades due to its extensive applications, so a vast body of work has developed optimization algorithms to solve SVM with ...various soft-margin losses. To distinguish all, in this paper, we aim at solving an ideal soft-margin loss SVM: <inline-formula><tex-math notation="LaTeX">L_{0/1}</tex-math> <mml:math><mml:msub><mml:mi>L</mml:mi><mml:mrow><mml:mn>0</mml:mn><mml:mo>/</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msub></mml:math><inline-graphic xlink:href="wang-ieq2-3092177.gif"/> </inline-formula> soft-margin loss SVM (dubbed as <inline-formula><tex-math notation="LaTeX">L_{0/1}</tex-math> <mml:math><mml:msub><mml:mi>L</mml:mi><mml:mrow><mml:mn>0</mml:mn><mml:mo>/</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msub></mml:math><inline-graphic xlink:href="wang-ieq3-3092177.gif"/> </inline-formula>-SVM). Many of the existing (non)convex soft-margin losses can be viewed as one of the surrogates of the <inline-formula><tex-math notation="LaTeX">L_{0/1}</tex-math> <mml:math><mml:msub><mml:mi>L</mml:mi><mml:mrow><mml:mn>0</mml:mn><mml:mo>/</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msub></mml:math><inline-graphic xlink:href="wang-ieq4-3092177.gif"/> </inline-formula> soft-margin loss. Despite its discrete nature, we manage to establish the optimality theory for the <inline-formula><tex-math notation="LaTeX">L_{0/1}</tex-math> <mml:math><mml:msub><mml:mi>L</mml:mi><mml:mrow><mml:mn>0</mml:mn><mml:mo>/</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msub></mml:math><inline-graphic xlink:href="wang-ieq5-3092177.gif"/> </inline-formula>-SVM including the existence of the optimal solutions, the relationship between them and P-stationary points. These not only enable us to deliver a rigorous definition of <inline-formula><tex-math notation="LaTeX">L_{0/1}</tex-math> <mml:math><mml:msub><mml:mi>L</mml:mi><mml:mrow><mml:mn>0</mml:mn><mml:mo>/</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msub></mml:math><inline-graphic xlink:href="wang-ieq6-3092177.gif"/> </inline-formula> support vectors but also allow us to define a working set. Integrating such a working set, a fast alternating direction method of multipliers is then proposed with its limit point being a locally optimal solution to the <inline-formula><tex-math notation="LaTeX">L_{0/1}</tex-math> <mml:math><mml:msub><mml:mi>L</mml:mi><mml:mrow><mml:mn>0</mml:mn><mml:mo>/</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msub></mml:math><inline-graphic xlink:href="wang-ieq7-3092177.gif"/> </inline-formula>-SVM. Finally, numerical experiments demonstrate that our proposed method outperforms some leading classification solvers from SVM communities, in terms of faster computational speed and a fewer number of support vectors. The bigger the data size is, the more evident its advantage appears.
Wide-bandgap all-inorganic CsPbIBr 2 solar cells with MoO x /Ag/TeO 2 composite transparent electrode have been firstly used to construct a 4T perovskite/Si-heterojunction tandem cells. The ...calculation results showed that the long wavelength transmission (600 to 1100 nm) of MoO x /Ag film can be enhanced remarkably by adding a TeO 2 optical capping layer. This resulted in an obviously increase of the PCE (J SC ) from 10.70% (17.56 mA/cm 2 ) to 14.76% (24.67 mA/cm 2 ) for corresponding bottom Si cell in CsPbIBr 2 /Si devices, although the PCE of top CsPbIBr 2 cell decreased from 17.52% to 16.58%, the overall PCE of tandem device has increased from 28.22% to 31.34%. This J SC -dependent PCE improvement mainly came from the more balanced light absorption, which can be understood by the optical interference induced light field redistributions in CsPbIBr 2 /Si devices. Specially, comparing with the original Si cell, the J SC and PCE losses in bottom Si cell have been suppressed to about 33% and 32%, which are superior to most the reported pervoskite/Si tandem cells. Therefore, the tandem of Si cell and CsPbIBr 2 cell with optimized MoO x (20 nm)/Ag(8 nm)/TeO 2 (50 nm) transparent electrode could be the promising cost-effective photovoltaic in the future. This work is instructive to the fabrication of pervoskite/Si tandem solar cells.
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