检索结果-南通市图书馆

A New Phasor Estimator for PMU Applications:P Class and M Class

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2020年第1期8卷 55-66页

作者： Jose R.Razo-Hernandez Arturo Mejia-Barron David Granados-Lieberman Martin Valtierra-Rodriguez Jose f.gomez-Aguilar ENAP-Research Group Facultad de IngenieríaUniversidad Autónoma de Querétaro(UAQ)San CayetanoC.P.76807México ENAP-Research Group Departamento de Ingeniería ElectromecánicaInstituto Tecnológico Superior de Irapuato(ITESI)Colonia El CopalC.P.36821México CONACyT-Centro Nacional de Investigación y Desarrollo Tecnológico(CENIDET) Tecnológico Nacional de MéxicoInterior Internado Palmira S/NCol.PalmiraC.P.62490México

Phasor measurement units(PMUs)are fundamental tools in the applications of modern power systems,where synchronized phasor estimations are *** accuracy and dynamic performance requirements for phasor,frequency,and rate of change of frequency(ROCOf)estimations are established in the IEEE Std.C37.118.1-2011 along with the IEEE Std.C37.118.1 a-2014,where two PMU performances are suggested:P class filters for applications requiring fast response and M class filters for applications requiring high rejection to aliased *** this paper,a methodology to design new phasor estimators that satisfy the P class and M class requirements in PMUs is *** proposed methodology is based on finite impulse response filters,brick-wall filters,and complex filter design concepts,where frequency range,time performance,harmonic rejection and out-of-band interference requirements are considered in its design.A comparative analysis using the reference model given by the IEEE Std.C37.118.1 is *** results show the effectiveness of the phasor estimators under steady-state and dynamic conditions according to the PMU standard,making them suitable tools for applications in power systems.

关键词： Brick-wall filter complex filter IEEE Std.C37.118.1 M class P class phasor measurement unit(PMU) phasor estimator

A generalization of the half-normal distribution

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of Chinese Universities) 2016年第4期31卷 409-424页

作者： Yolanda M. gomez Ignacio Vidal departamento de matemáticas facultad de ciencias universidad de católica del norte Antofagasta Chile instituto de matemática y física universidad de talca Chile

In this paper we introduce an extension of the half-normal distribution in order to model a great variety of non-negative data. Its hazard rate function can be decreasing or increasing, depending on its parameters. Some properties of this new distribution are presented. for example, we give a general expression for the moments and a stochastic representation. Also, the cumulative distribution function, the hazard rate function, the survival function and the quantile function can be easily evaluated. Maximum likelihood estimators can be computed by using numerical procedures. finally, a real-life dataset has been presented to illustrate its applicability.

关键词： half-normal distribution generalized half-normal distribution maximum likelihood estimate

Effect of Mitochondrial Dysfunction on Carbon Metabolism and Gene Expression in flower Tissues of Arabidopsis thaliana

在线全文

学校读者我要写书评

暂无评论

Molecular Plant 2011年第1期4卷 127-143页

作者： Maria V. Busi Maria E. gomez-Lobato Sebastian P. Rius Valeria R. Turowski Paula Casati Eduardo J. Zabaleta Diego f. gomez-Casati Alejandro Araya Instituto de Investigaciones Biotecnologicas-lnstituto Tecnologico de ChascomOs (IIB-INTECH) CONICET/UNSAM Chascomus Argentina Centro de Estudios fotosinteticos y Bioquimicos (CEfOBI) Universidad Nacional de Rosario Argentina Instituto de Investigaciones Biologicas liB CONICET-Universidad Nacional de Mar del Plata Argentina Microbiologie Cellulaire et Moleculaire et Pathogenicite UMR 5234 Centre National de la Recherche Scientifique and Universite Victor Segalen-Bordeaux 2 Bordeaux France

We characterized the transcriptomic response of transgenic plants carrying a mitochondrial dysfunction induced by the expression of the unedited form of the ATP synthase subunit 9. The u-ATP9 transgene driven by A9 and APETALA3 promoters induce mitochondrial dysfunction revealed by a decrease in both oxygen uptake and adenine nucleo- tides （ATP, ADP） levels without changes in the ATIP/ADP ratio. furthermore, we measured an increase in ROS accumulation and a decrease in glutathione and ascorbate levels with a concomitant oxidative stress response. The transcriptome analysis of young Arabidopsis flowers, validated by qRT-PCR and enzymatic or functional tests, showed dramatic changes in u-ATP9 plants. Both lines display a modification in the expression of various genes involved in carbon, lipid, and cell wall metabolism, suggesting that an important metabolic readjustment occurs in plants with a mitochondrial dysfunction. Interestingly, transcript levels involved in mitochondrial respiration, protein synthesis, and degradation are affected. More- over, the levels of several mRNAs encoding for transcription factors and DNA binding proteins were also changed. Some of them are involved in stress and hormone responses, suggesting that several signaling pathways overlap. Indeed, the tran- scriptome data revealed that the mitochondrial dysfunction dramatically alters the expression of genes involved in signaling pathways, including those related to ethylene, absicic acid, and auxin signal transduction. Our data suggest that the mitochondrial dysfunction model used in this report may be useful to uncover the retrograde signaling mechanism between the nucleus and mitochondria in plant cells.

关键词： Electron transport transcriptome analysis Arabidopsis.

Keratoconus in a patient with Alport syndrome: A case report

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2019年第19期7卷 3012-3017页

作者： Majid Moshirfar David f Skanchy Aaron T gomez Yasmyne C Ronquillo Benjamin Buckner Phillip C Hoopes John A.Moran Eye Center Department of Ophthalmology and Visual SciencesUniversity of Utah School of MedicineSalt Lake CityUT 84101United States Utah Lions Eye Bank Salt Lake CityUT 84101United States Hoopes Durrie Rivera Research Center Hoopes VisionDraperUT 84020United States Kellogg Eye Center Department of OphthalmologyUniversity of Michigan Medical SchoolAnn ArborMI 48103United States The University of Texas Rio Grande Valley School of Medicine EdinburgTX 78542United States

BACKGROUND Known ocular manifestations of Alport syndrome include features such as anterior lenticonus and fleck retinopathy. Reports of keratoconus in such patients are limited. We report tomographic findings consistent with keratoconus in a patient with Alport *** SUMMARY A 52-year-old female was referred to our ophthalmology clinic with decreased vision and increased tearing. She was diagnosed with stage Ⅲ Alport syndrome two years prior. Upon examination she was found to have average keratometries of 48D bilaterally with tomographic evidence of *** Although a rare presentation, concurrent Alport syndrome and keratoconus should be considered when reviewing the ocular health of Alport syndrome patients and appropriate management steps should be taken upon the diagnosis.

关键词： Alport syndrome,Keratoconus Type Ⅳ collagen COL4A genes Corneal ectasia Case report

Strain engineering in single-,bi-and tri-layer MoS_(2),MoSe_(2),WS_(2)and WSe_(2)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2021年第6期14卷 1698-1703页

作者： felix Carrascoso Hao Li Riccardo frisenda Andres Castellanos-gomez Materials Science factory Instituto de Ciencia de Materiales de MadridConsejo Superior de Investigaciones Cientificas28049MadridSpain

Strain is a powerful tool to modify the optical properties of semiconducting transition metal dichalcogenides like MoS_(2),MoSe_(2),WS_(2) and WSe_(2).In this work we provide a thorough description of the technical details to perform uniaxial strain measurements on these two-dimensional semiconductors and we provide a straightforward calibration method to determine the amount of applied strain with high *** then employ reflectance spectroscopy to analyze the strain tunability of the electronic properties of single-,bi-and tri-layer MoS_(2),MoSe_(2),WS_(2) and WSe_(2).finally,we quantify the flake-to-flake variability by analyzing 15 different single-layer MoS_(2) flakes.

关键词： two-dimensional(2D)materials transition metal dichalcogenides strain engineering band gap differential reflectance

Large solitary ovarian metastasis from colorectal cancer diagnosed by endoscopic ultrasound

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2008年第32期14卷 5096-5097页

作者： Bhavani Moparty Guillermo gomez Manoop S Bhutani Department of Internal Medicine University of Texas Medical Branch Department of Surgery University of Texas Medical Branch Department of Gastrointestinal Medicine and Nutrition UT MD Anderson Cancer Center

A case is presented of rectal carcinoma in which during staging by endoscopic ultrasound （EUS） a second large extra recta l mass was seen not otherwise visualized on computer tomograghy （CT） that was a solitary ovarian metastasis. The surgeon was alerted to the EUS finding prior to the planned laparoscopic colectomy. On retrospective review of the CT pelvis after surgery, the radiologist could still not diagnose the ovarian lesion separated from the primary rectal tumor due to their close proximity. However, on EUS we were able to clearly see on real-time imaging that there was a distinct peri-rectal mass apart from the primary rectal tumor.

关键词： Colorectal Cancer Endoscopic ultrasound Ovary Ovarian metastasis Endoscopic ultrasound Endosonography

Orientation effect on ground motion measurement for Mexican subduction earthquakes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2009年第1期8卷 1-16页

作者： H.P. Hong A. Pozos-Estrada R. gomez Department of Civil and Environmental Engineering University of Western Ontario Canada N6A 5B9 Institute of Engineering National Autonomous University of Mexico Mexico D.F.

The existence of the principal directions of the ground motion based on Arias intensity is well-known. These principal directions do not necessarily coincide with the orientations of recording sensors or with the orientations along which the ground motion parameters such as the peak ground acceleration and the pseudo-spectral acceleration （PSA） are maximum. This is evidenced by the fact that the maximum PSA at different natural vibration periods for horizontal excitations do not correspond to the same orientation. A recent analysis carried out for California earthquake records suggests that an orientation-dependent ground motion measurement for horizontal excitations can be developed. The main objective of this study is to investigate and provide seismic ground motion measurements in the horizontal plane, including bidirectional horizontal ground motions, for Mexican interplate and inslab earthquake records. Extensive statistical analyses of PSA are conducted for the assessment. The analysis results suggest that similar to the case of California records, the average behavior of the ratio of the PSA to the maximum resulting PSA can be approximated by a quarter of an ellipse in one quadrant; and that the ratio can be considered to be independent of the value of the maximum resulting PSA, earthquake magnitude, earthquake distance and the focal depth. Sets of response ratios and attenuation relationships that can be used to represent a bidirectional horizontal ground motion measurement for Mexican interplate and inslab earthquakes were also developed.

关键词： orthogonal horizontal excitations bidirectional ground motion measure attenuation relationship pseudospectral acceleration (PSA) response ratio Mexican earthquake

One step synthesis of high efficiency nickel/mesoporous TiO_2 hybrid catalyst for hydrogen evolution reaction

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2019年第2期28卷 79-87页

作者： Esteban A.franceschini Melisa J.gomez Gabriela I.Lacconi INfIQC-CONICET Dto.de Fisicoquímica – Facultad de Ciencias QuímicasUniversidad Nacional de CórdobaCiudad Universitaria Departamento de física de la Materia Condensada Centro Atómico ConstituyentesComisión Nacional de Energía Atómica

Nickel-Ti O_2 hybrid catalysts are synthesized by electrodeposition and their catalytic activity with respect to the hydrogen evolution reaction is *** types of titanium oxide particles,which are commercial particles of dense Ti O_2 and mesoporous TiO_2 particles synthesized by an aerosol method,are incorporated into the matrix of the nickel *** nickel catalysts containing Ti O_2 particles presented higher catalytic activity than the conventional nickel Watts *** TiO_2-modified nickel catalyst showed the highest catalytic activity towards HER in alkaline *** addition,this type of nickel catalyst increases its catalytic activity after ageing treatment,which is an indication of an increase in the electro-active area of the electrode.

关键词： Co-deposition Impedance spectroscopy Titanium oxide Ageing process Raman spectroscopy

Durgapal IV model considering the minimal geometric deformation approach

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2020年第10期44卷 152-168页

作者： francisco Tello-Ortiz Ángel Rincon Piyali Bhar Y.gomez-Leyton Departamento de física Facultad de ciencias básicasUniversidad de AntofagastaCasilla 170AntofagastaChile Instituto de física Pontificia Universidad Católica de ValparaísoAvenida Brasil 2950Casilla 4059ValparaísoChile Department of Mathematics Government General Degree CollegeSingurHooghlyWest Bengal 712409India Departamento de física Universidad Católica del NorteAv.Angamos 0610AntofagastaChile

The present article reports the study of local anisotropic effects on Durgapal's fourth model in the context of gravitational decoupling via the minimal geometric deformation *** achieve this,the most general equation of state relating the components of the−θsector is imposed to obtain the decoupler function f(r).In addition,certain properties of the obtained solution,such as the behavior of the salient material content threading the stellar interior;causality and energy conditions;hydrostatic balance through the modified Tolman−Oppenheimer−Volkoff conservation equation and stability mechanism against local anisotropies using the adiabatic index;sound velocity of the pressure waves;convection factor;and the Harrison−Zeldovich−Novikov procedure,are investigated to check whether the model is physically admissible or *** the stability analysis,it is found that the model presents unstable regions when the sound speed of the pressure waves and convection factor are used in distinction with the adiabatic index and Harrison−Zeldovich−Novikov *** produce a more realistic picture,the numerical data for some known compact objects were determined and different values of the parameterαwere considered to compare with the GR case,i.e.,α=0.

关键词： compact objects anisotropy gravitational decoupling