49 research outputs found

    Mitigation of Voltage flicker and reduction in THD by using STATCOM

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    Voltage flicker is considered as one of the most severe power quality problems (especially in loads like electrical arc furnaces) and much attention has been paid to it lately. Due to the latest achievements in the semiconductors industry and consequently the emergence of the compensators based on voltage source converters, FACTS devices have been gradually noticed to be used for voltage flicker compensation. This paper covers the contrasting approaches; dealing with the voltage flicker mitigation in three stages and reduction in total harmonic distortion and assessing the related results in details. Initially, the voltage flicker mitigation, using FCTCR (Fixed Capacitor Thyristor Controlled Reactor), was simulated. Secondly, the compensation for the six-pulse as well as 12-pulse Static Synchronous Compensator (STATCOM) has been performed. In this case, injection of harmonics into the system caused some problems which were later overcome by using 12-pulse assignment of SATCOM and RLC filter (three phase harmonic filter). The obtained results show that STATCOM is very efficient and effective for the flicker compensation as well as harmonic sprectrum. All the simulations have been performed on the MATLAB Software.DOI:http://dx.doi.org/10.11591/ijece.v3i1.195

    PRACTICAL IMPLEMENTATION OF TRAIN ACCIDENTS AVOIDANCE SYSTEM USING IOT PLATFORM

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    For railroad practices far and wide, plan back mischance catastrophes on occasion happen, accomplishing noteworthy challenges and property disaster. To maintain a strategic distance from the event of such scenes, a novel early admonishing system for plan following interim in light of bound together activity control (CTC), or only CTC between times preparing, is proposed. Right when joined with the current changed arrangement security, the seeing of prepare after between time is expanded. The proposed methodology enlists the base success break powerfully and contrasts it and the certified spatial division. Precisely when the genuine spatial separation isn't as much as the base flourishing interim, especially when the ATP is to be blamed, the proposed strategy is fit for raising the alert and taking control measures to sensibly keep up an essential detachment from raise mischance setbacks. In the interim, this procedure clears the manual supervision of prepare task, in like way quieting work control, and enhances the appropriateness of supervision

    Automatic license plate recognition using pre-processing methods

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    In this paper, we present a method to automatically detect a vehiclersquos number by usingnbsp pre-processing techniques. We also include image enhancement techniques, edge detection methods, morphological methods including image filling and some techniques like image filling. This paper provides an advantage of effective detection of more number of vehicles compared to the detection using edge detection methods.nbs

    Influence of lattice distortion on the Curie temperature and spin-phonon coupling in LaMn0.5_{0.5}Co0.5_{0.5}O3_{3}

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    Two distinct ferromagnetic phases of LaMn0.5_{0.5}Co0.5_{0.5}O3_{3} having monoclinic structure with distinct physical properties have been studied. The ferromagnetic ordering temperature Tc\textit{T}_{c} is found to be different for both the phases. The origin of such contrasting characteristics is assigned to the changes in the distance(s) and angle(s) between Mn - O - Co resulting from distortions observed from neutron diffraction studies. Investigations on the temperature dependent Raman spectroscopy provide evidence for such structural characteristics, which affects the exchange interaction. The difference in B-site ordering which is evident from the neutron diffraction is also responsible for the difference in Tc\textit{T}_{c}. Raman scattering suggests the presence of spin-phonon coupling for both the phases around the Tc\textit{T}_{c}. Electrical transport properties of both the phases have been investigated based on the lattice distortion.Comment: 9 figure

    Loss of Serpina1 in Mice Leads to Altered Gene Expression in Inflammatory and Metabolic Pathways

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    The SERPINA1 gene encodes alpha1-antitrypsin (AAT), an acute phase glycoprotein and serine protease inhibitor that is mainly (80-90%) produced in the liver. Point mutations in the SERPINA1 gene can lead to the misfolding, intracellular accumulation, and deficiency of circulating AAT protein, increasing the risk of developing chronic liver diseases or chronic obstructive pulmonary disease. Currently, siRNA technology can knock down the SERPINA1 gene and limit defective AAT production. How this latter affects other liver genes is unknown. Livers were taken from age- and sex-matched C57BL/6 wild-type (WT) and Serpina1 knockout mice (KO) aged from 8 to 14 weeks, all lacking the five serpin A1a-e paralogues. Total RNA was isolated and RNA sequencing, and transcriptome analysis was performed. The knockout of the Serpina1 gene in mice changed inflammatory, lipid metabolism, and cholesterol metabolism-related gene expression in the liver. Independent single-cell sequencing data of WT mice verified the involvement of Serpina1 in cholesterol metabolism. Our results from mice livers suggested that designing therapeutic strategies for the knockout of the SERPINA1 gene in humans must account for potential perturbations of key metabolic pathways and consequent mitigation of side effects.RNA sequencing was supported by the grant ISCIII-AESI PI20CIII/00015.S

    Neutrino mixing matrices with relatively large θ13\theta_{13} and with texture one-zero

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    The recent T2K, MINOS and Double Chooz oscillation data hint a relatively large θ13\theta_{13}, which can be accommodated by some general modification of the Tribimaximal/Bimaximal/Democratic mixing matrices. Using such matrices we analyze several Majorana mass matrices with texture one-zero and show whether they satisfy normal or inverted mass hierarchy and phenomenologically viable or not.Comment: 16 pages, 3 figures, minor modification in the text, version to appear in EPJ

    Nucleophilic Substitution at a Coordinatively Saturated Five-Membered NHC∙Haloborane Centre

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    In this paper, we have used a saturated five-membered N-Heterocyclic carbene (5SIDipp = 1,3-bis-(2,6-diisopropylphenyl)imidazolin-2-ylidine) for the synthesis of SNHC-haloboranes adducts and their further nucleophilic substitutions to put unusual functional groups at the central boron atom. The reaction of 5-SIDipp with RBCl2 yields Lewis-base adducts, 5-SIDipp·RBCl2 [R = H (1), Ph (2)]. The hydrolysis of 1 gives the NHC stabilized boric acid, 5-SIDipp·B(OH)3 (3), selectively. Replacement of chlorine atoms from 1 and 2 with one equivalent of AgOTf led to the formation of 5-SIDipp·HBCl(OTf) (4) and 5-SIDipp·PhBCl(OTf) (5a), where all the substituents on the boron atoms are different. The addition of two equivalents of AgNO3 to 2 leads to the formation of rare di-nitro substituted 5-SIDipp·BPh(NO3)2 (6). Further, the reaction of 5-SIDipp with B(C6F5)3 in tetrahydrofuran and diethyl ether shows a frustrated Lewis pair type small molecule activated products, 7 and 8
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