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Virtual Conductance Based Cascade Voltage Controller for VSCs in Islanded Operation Mode

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1704-1713页

作者： Francisco Jesús Matas-Díaz manuel Barragán-Villarejo Juan Carlos Olives-Camps Juan manuel Mauricio joséMaría Maza-Ortega Department of Elec‐trical Engineering Universidad de SevillaSeville 41092Spain

Voltage source converters have become the main enabler for the integration of distributed energy resources in *** the case of islanded operation,these devices normally set the amplitude and frequency of the network voltage by means of a cascade controller composed of an outer voltage control loop and an inner current control *** strategies to compute the gains of both control loops have been proposed in the literature in order to obtain a fast and decoupled response of the voltages at the point of common *** paper proposes an alternative and simple methodology based on the introduction of a virtual conductance in the classic cascade *** strategy allows to design each control loop independently,obtaining a closed-loop response of a first-order *** this way,the gains of each control loop are easily derived from the parameters of the LC coupling filter and the desired closed-loop time ***,a state observer is included in the controller to estimate the inductor current of the LC filter in order to reduce the number of required measurements.A laboratory testbed is used to validate and compare the proposed *** experimental results demonstrate the effectiveness of the proposal both in steady-state and transient regimes.

关键词： Voltage source converter microgrid cascade controller virtual conductance

Effect of magnetic field orientation on fluidized beds of magnetic particles:Theory and experiment

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Particuology 2014年第1期12卷 54-63页

作者： Miguel ángel Sánchez Quintanilla manuel Jesús Espin josé manuel Valverde Department of Electronics and Electromagnetism University of Seville Department of Applied PhysicsⅡ University of Seville

Geldart-A fluidized beds of fine particles experience a jamming transition between a fluid-like state and a solid-like state at a certain superficial gas velocity, that depends on the relative strength of interparticle attractive forces with respect to particle weight, lnterparticle forces provide the bed with a certain tensile strength in the jammed state. In the work presented here we analyze the behavior of a fluidized bed of magnetic particles subjected to an externally applied magnetic field, which contributes to enhance interparticle forces. The importance of the magnetic contribution to interparticle forces is measured by the changes in the tensile strength and the superficial gas velocity at the jamming transition. The link of the field orientation with the microstructure of the bed is discussed,

关键词： Magneto-fluidization Jamming transition Fluidization Fine powders Cohesion Magnetization

An optimized high quality male DnA extraction from spermatophores in open thelycum shrimp species

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Integrative Zoology 2017年第5期12卷 421-427页

作者： Laia PLAnELLA Sandra HERAS manuel VERA josé-Luis GARCÍA-MARÍn María Inés ROLDÁn Laboratory of Genetic Ichthyology University of GironaGironaSpain

The crucial step of most of the current genetic studies is the extraction of DnA of sufficient quantity and *** genomic DnA isolation methods have been described to successfully obtain male DnA from shrimp ***,all current protocols require invasive handling methods with males for DnA *** Aristeus antennatus as a model we tested a reliable non-invasive differential DnA extraction method to male DnA isolation from spermatophores attached to female *** present protocol provides high quality and quantity DnA for polymerase chain reaction amplification and male *** new approach could be useful to experimental shrimp culture to select sires with relevant genetic patterns for selective breeding *** importantly,it can be applied to identify the mating pairs and male structure in wild populations of species as ***,where males are often difficult to *** method could be also valuable for biological studies on other spermatophore-using species,such as myriapods,arachnids and insects.

关键词： differential spermatophore DnA extraction high quality DnA male genotyping non-invasive DnA extraction open thelycum shrimp

Steatosis and insulin resistance in hepatitis C: A way out for the virus?

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World Journal of Gastroenterology 2009年第40期15卷 5014-5019页

作者： josé A Del Campo manuel Romero-Gómez Unit for The Clinical Management of Digestive Diseases and CIBERehd Hospital Universitario de Valme

The hepatitis C virus (HCV) induces lipid accumulation in vitro and in vivo. The pathogenesis of steatosis is due to both viral and host factors. Viral steatosis is mostly reported in patients with genotype 3a, whereas meta-bolic steatosis is often associated with genotype 1 and metabolic syndrome. Several molecular mechanisms responsible for steatosis have been associated with the HCV core protein, which is able to induce gene expres-sion and activity of sterol regulatory element binding protein 1 (SREBP1) and peroxisome proliferator-activat-ed receptor γ (PPARγ), increasing the transcription of genes involved in hepatic fatty acid synthesis. Steatosis has been also implicated in viral replication. In infected cells, HCV core protein is targeted to lipid droplets which serve as intracellular storage organelles. These studies have shown that lipid droplets are essential for virus assembly. Thus, HCV promotes steatosis as an eff icient mechanism for stable viral replication. Chronic HCV in-fection can also induce insulin resistance. In patients with HCV, insulin resistance is more strongly associated with viral load than visceral obesity. HCV seems to lead to insulin resistance through interference of intracellular insulin signalling by HCV proteins, mainly, the serine phosphorylation of insulin receptor-1 (IRS-1) and im-pairment of the downstream Akt signalling pathway. The HCV core protein interferes with in vitro insulin signal-ling by genotype-specif ic mechanisms, where the role of suppressor of cytokine signal 7 (SOCS-7) in genotype 3aand mammalian target of rapamycin (mTOR) in geno-type 1 in IRS-1 downregulation play key roles. Steatosis and insulin resistance have been associated with f ibrosis progression and a reduced rate of sustained response to peginterferon plus ribavirin.

关键词： Steatosis Insulin resistance Hepatitis Cvirus

Software Vulnerabilities Overview:A Descriptive Study

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Tsinghua Science and Technology 2020年第2期25卷 270-280页

作者： Mario Calín Sánchez Juan manuel Carrillo de Gea josé Luis Fernández-Alemán Jesús Garcerán Ambrosio Toval the Department of Informatics and Systems Faculty of Computer ScienceUniversity of Murcia

Computer security is a matter of great *** the last decade there have been numerous cases of cybercrime based on the exploitation of software *** fact has generated a great social concern and a greater importance of computer security as a *** this work,the most important vulnerabilities of recent years are identified,classified,and categorized individually.A measure of the impact of each vulnerability is used to carry out this classification,considering the number of products affected by each vulnerability,as well as its *** addition,the categories of vulnerabilities that have the greatest presence are *** on the results obtained in this study,we can understand the consequences of the most common vulnerabilities,which software products are affected,how to counteract these vulnerabilities,and what their current trend is.

关键词： descriptive study software security software vulnerabilities vulnerability databases

Preparation and Characterization of Flexible, Transparent and Thermally Stable Aromatic Co-polyamides

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Chinese Journal of Polymer Science 2019年第2期37卷 136-141页

作者： josé Antonio Tec-Sánchez Andrés Iván Oliva Arias manuel Aguilar-Vega Juan Valerio Cauich-Rodríguez josé Luis Santiago-García Unidad de Materiales Centro de Investigación Científica de Yucatán A. C. Centro de Investigación y de Estudios Avanzados del IPn Unidad Mérida Departamento de Física Aplicada

Two aromatic co-polyamides were synthesized combining two diacid monomers containing bulky pendant groups, 5-(9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboximido)isophthalic acid(DEAIA) and 5-tert-butylisophthalic acid(TERT), with 4,4′-(hexafluoroisopropylidene)dianiline(HFA) or 2,3,5,6-tetramethyl-1,4-phenylenediamine(durene) by direct polycondensation. The structures of the obtained aromatic co-polyamides were confirmed by FTIR, Raman and 1 H-nMR. The co-copolyamide films, DHTH and DDTD, exhibited rms-roughness values between 0.94 and 1.60 nm, respectively. Moreover, they presented good thermal stability up to300 °C. Young's moduli of the co-polyamide films were between 4.1 and 4.3 GPa. X-ray diffraction results showed that the co-polyamide films were amorphous due to the incorporation of both bulky pendant groups, tert-butyl and dibenzobarrelene. The combination of bulky pendant groups provided intrinsically transparent co-polyamide films with a transmittance higher than 88% in the range of 400-780 *** to these outstanding film and optical properties, they are suggested to be flexible substrates in applications for solar cell and other portable electronic devices.

关键词： Co-polyamides Flexible films Transmittance Thermal stability Polycondensation

Effect of rhenium on the microstructure and mechanical behavior of Fe–2.25Cr–1.6W–0.25V-0.1C bainitic steels

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Journal of Materials Science & Technology 2017年第12期33卷 1487-1493页

作者： josé Antonio Jiménez manuel Carsí Oscar Antonio Ruano Department of Physical Metallurgy Centro Nacional de lnvestigaciones MetalurgicasC.S.I.CAvda.Gregorio del Amo 828040 MadridSpain

A new ferritic creep resistant steel has been developed by eliminating nb and adding 1.5 mass % Re to a ferritic steel grade T/P23 with the aim of enhancing its mechanical properties at high *** ingots of both steels, new grade and ASTM T/P 23, were hot rolled at 900℃ and then submitted to a thermal treatment consisting of solubilization at 1050℃ and tempering at 700℃. Tempered bainitic microstructures obtained contain second phases reinforcing carbide particles, mainly M_6C and M_（23）C_6 at the boundaries of both, prior austenite grains and bainitic ferrite laths, as well as MC within the grains. Mechanical properties at temperatures ranging from 540 to 600℃ were studied by strain-ratechange tests in compression at strain rates between 10^（-7） and 10^（-4）s^（-1）. These tests showed high stress exponents（n ≥ 20） and activation energies（Q ≈ 400 k J/mol） for both alloys, which were associated with a dislocation movement mechanism with a strong interaction between dislocations and precipitates. On the other hand, a creep exponent of 5 was derived for the stress dependence of minimum creep rate from conventional-type creep tests at 600℃. Although this stress exponent is usually related to a dislocation climb controlled creep mechanism, remarkable microstructural degradation observed with increasing creep time makes difficult to elucidate the true deformation mechanism controlling creep.

关键词： Creep resistant steel T/P23 Thermal treatment Tempered bainite High temperature mechanical properties Creep

Precipitation Kinetics on a nb-V Microalloyed Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 148-153页

作者： Cartaya Elio Armando Cabrera josé María Prado josé manuel Departamento de Ciencia de Materiales e Ingeniería Metalúrgica ETSEIBUniversidad Politécnica de Catalua Av.Diagonal 64708028 BarcelonaSpain Departamento de Manufactura y Materiales Facultad de Ingeniería MecánicaUniversidad de OrienteSantiago de CubaCuba Fundación CTM Centro Tecnológico Av.Bases de Manresa 108242 ManresaSpain

The precipitation kinetics in a low carbon high strength low alloy (HSLA) steel,microalloyed with V+nb has been studied by using the stress relaxation *** technique was carried out in a dynamic dilatometer and allows to determine the onset and finishing precipitation times in hot deformed *** evolution of the precipitates was also observed using field emission scanning electron microscopy (FESEM) on samples quenched at different times at given *** is completed with the predictions by the thermodynamic software FactSage to identify stable precipitate phases under equilibrium *** confirm the feasibility of the stress relaxation technique as an efficient method for investigating precipitation kinetics.

关键词： stress relaxation microalloyed steels precipitation FESEM

Fully integrated and broadband Si-rich silicon nitride wavelength converter based on Bragg scattering intermodal four-wave mixing

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Photonics Research 2024年第3期12卷 I0001-I0010页

作者： VALERIO VITALI THALÍA DOMÍnGUEZ BUCIO HAO LIU josÉmanuel LUQUE GOnZÁLEZ FRAnCISCO JURADO-ROMERO ALEJAnDRO ORTEGA-MOÑUX GLEnn CHURCHILL JAMES C.GATES JAMES HILLIER nIKOLAOS KALFAGIAnnIS DAnIELE MELATI JEnS H.SCHMID ILARIA CRISTIAnI PAVEL CHEBEn J.GOnZALO WAnGÜEMERT-PÉREZ ÑIGO MOLInA-FERnÁnDEZ FREDERIC GARDES COSIMO LACAVA PERIKLIS PETROPOULOS Optoelectronics Research Centre University of SouthamptonSouthampton SO171BJUK Electrical Computer and Biomedical Engineering DepartmentUniversity of PaviaPavia 27100Italy Telecommunication Research Institute(TELMA) Universidad de MálagaCEI Andalucı´a TECHE.T.S.I.Telecomunicación29010 MálagaSpain School of Science and Technology Nottingham Trent UniversityNottingham NG118NSUK Department of Electrical Engineering Eindhoven University of TechnologyEindhoven 5600 MBThe Netherlands Department of Materials Science and Engineering University of IoanninaIoannina 45110Greece Centre de nanosciences et de nanotechnologies UniversitéParis-SaclayCNRS91120 PalaiseauFrance Advanced Electronics and Photonics Research Center National Research Council CanadaOttawaOntario K1A 0R6Canada

Intermodal four-wave mixing(FWM)processes have recently attracted significant interest for all-optical signal processing applications thanks to the possibility to control the propagation properties of waves exciting distinct spatial modes of the same *** allows,in principle,to place signals in different spectral regions and satisfy the phase matching condition over considerably larger bandwidths compared to intramodal ***,the demonstrations reported so far have shown a limited bandwidth and suffered from the lack of on-chip components designed for broadband manipulation of different *** demonstrate here a silicon-rich silicon nitride wavelength converter based on Bragg scattering intermodal FWM,which integrates mode conversion,multiplexing and de-multiplexing functionalities *** system enables wavelength conversion between pump waves and a signal located in different telecommunication bands(separated by 60 nm)with a 3 dB bandwidth exceeding 70 nm,which represents,to our knowledge,the widest bandwidth ever achieved in an intermodal FWM-based system.

关键词： scattering pump modal