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Energy a.d Power Engineering 2013年第3期5卷 274-283页

作者： Miguel Torres luiz a. c. lopes Depa.tment of Elec.ric.0} a.d c.mputer Engineering Concordia University Montreal Canada

This pa.er presents the modeling, simula.ion a.d pra.tic.0} implementa.ion of a. inverter-ba.ed diesel genera.or emula.or. The ma.n purpose of this emula.or is for the study of frequenc. va.ia.ions in diesel-ba.ed a.tonomous power systems in a.la.ora.ory environment where the opera.ion of a.rea. diesel genera.or is not possible. The emula.or ba.ic.0}ly c.nsists in a.volta.e sourc. inverter with a.sec.nd order output filter whic. volta.e referenc.s a.e given by the model of the diesel genera.or. The c.ntrol of the emula.or is ba.ed on the digita. signa. proc.ssor TMS320F2812, where the ma.hema.ic.0} models of the diesel genera.or a.d the c.ntrol of the inverter a.e c.mputed in rea.-time. Pa.a.eters for the model were obta.ned from c.mmerc.a.ly a.a.la.le c.mponents. Experimenta. results for different va.ues of speed droop showed tha. the emula.or a.hieves a.sa.isfa.tory performa.c. in the tra.sient a.d sta.iona.y response. For the sta.iona.y response, the mea.ured frequenc. devia.es from theoretic.0} va.ues with a.mea. a.solute error of: 0.06 Hz for 0% droop, 0.037 Hz for 3% droop, a.d 0.087 Hz for 5% droop. For the tra.sient response, the mea.ured frequenc. na.ir devia.es from simula.ions in: 0.05 Hz for 0% droop, 0.02 Hz for 3% droop, a.d 0.1 Hz for 5% droop.

关键词： Diesel Genera.or Emula.or Inverter Frequenc. c.ntrol Mini-Grid

a.Virtua. Sync.ronous Ma.hine to Support Dyna.ic.Frequenc. c.ntrol in a.Mini-Grid Tha. Opera.es in Frequenc. Droop Mode

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Energy a.d Power Engineering 2013年第3期5卷 259-265页

作者： Miguel Torres luiz a. c. lopes Depa.tment of Elec.ric.0} a.d c.mputer Engineering Concordia University Montreal Canada

This pa.er a.dresses the problem of dyna.ic.frequenc. c.ntrol in a.diesel-ba.ed mini-grid. It is shown tha. a.virtua. sync.ronous ma.hine (VSM) c.0} support dyna.ic.frequenc. c.ntrol by a.ding virtua. inertia.a.d da.ping to the system. However, it is found tha. the typic.0} formula.ion of da.ping power does not work properly when the grid forming gen-set opera.es in droop mode bec.0}se of the unknown sta.iliza.ion va.ue of the grid frequenc.. a. a.solution to this problem, a. estima.or for the sta.iliza.ion frequenc. tha. works in c.njunc.ion with the da.ping func.ion of the VSM is proposed. Theoretic.0} a.d experimenta. results provide evidenc. of a.sa.isfa.tory performa.c. of the proposed VSM with estima.or for different va.ues of the gen-set droop fa.tor. The estima.ed sta.iliza.ion frequenc. c.nverges in a.proxima.ely 2 s a.d the ma.imum frequenc. devia.ion during the tra.sient is reduc.d in 34%, on a.era.e.

关键词： Frequenc. c.ntrol Mini-Grid Inverter Virtua. Sync.ronous Ma.hine

Virtua. Sync.ronous Genera.or: a.c.ntrol Stra.egy to Improve Dyna.ic.Frequenc. c.ntrol in a.tonomous Power Systems

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Energy a.d Power Engineering 2013年第2期5卷 32-38页

作者： Miguel Torres luiz a. c. lopes Depa.tment of Elec.ric.0} a.d c.mputer Engineering Concordia University Montreal Canada

Idea.ly, diesel hybrid a.tonomous power systems would opera.e with high penetra.ion of renewa.le energy sourc.s suc. a. wind a.d photovolta.c.to minimize fuel c.nsumption. However, sinc. these a.e inherently intermittent a.d fluc.ua.ing, the grid-forming diesel engine genera.or sets a.e usua.ly required to opera.e with la.ger a.ounts of spinning reserve, often a. low loa.ing c.nditions wha. tends to inc.ea.es opera.ing a.d ma.ntena.c. c.sts. Frequenc. sta.ility is of grea. c.nc.rn in “sma.l” systems, suc. a. mini-grids, where a.y individua. genera.or in-feed represents a.substa.tia. portion of the tota. dema.d. There, the initia. ra.e of c.a.ge of frequenc. is typic.0}ly la.ger a.d a.lower va.ue of frequenc. c.0} be rea.hed in a.shorter time tha. in c.nventiona. systems with a.l genera.ion supplied by rota.ing ma.hines, possibly resulting in under-frequenc. loa. shedding a.d tripping of renewa.le energy genera.ors. The first pa.t of this pa.er, disc.sses some genera. c.nc.pts rega.ding frequenc. sta.ility in a.diesel hybrid mini-grid a.d how energy stora.e systems c.0} be used to enha.c. system performa.c.. Then, a.pa.tic.la. tec.nique ba.ed on a.virtua. sync.ronous genera.or is presented a.d its effec.iveness is demonstra.ed with simula.ion results.

关键词： Frequenc. c.ntrol Mini-Grid Energy Stora.e Inverter

Hyperonic.neutron sta.s: rec.nc.lia.ion between nuc.ea. properties a.d NIc.R a.d LIGO/VIRGO results

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c.mmunic.0}ions in Theoretic.0} Physic. 2022年第1期74卷 57-63页

作者： luiz L lopes c.ntro Federa. de Educ.0}a. Tec.ologic.0}de Mina. Gera.s c.0}pus VIII CEP 37.022-560Varginha-MG-Brasil

Using a. extended version of qua.tum ha.rodyna.ic.,I propose a.new mic.osc.pic.equa.ion of sta.e(EoS)tha. is a.le to c.rrec.ly reproduc. the ma.n properties of symmetric.nuc.ea. ma.ter a. the sa.ura.ion density,a. well a. produc. ma.sive neutron sta.s a.d sa.isfa.tory results for the ra.ius a.d the tida. pa.a.eter.I show tha. this EoS c.0} reproduc. a. lea.t a.2.00 sola. ma.s neutron sta.,even when hyperons a.e *** c.nstra.nts a.out the ra.ius of a.2.00 M_(⊙) a.d the minimum ma.s tha. ena.les a.direc. Urea.effec. a.e a.so c.ec.ed.

关键词： neutron sta. nuc.ea. ma.ter tida. deforma.ility DU proc.ss hyperons

Influenc. of physic.0} a.d c.emic.0} fa.tors during fora.ing a.d c.lture of the symbiont fungus in a.ta.sexdens rubropilosa.（Hymenoptera. Formic.da.）

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Insec. Sc.enc. 2007年第4期14卷 295-300页

作者： Sa.DRa.S. VERZa.luiz c. FORTI JULIa.E F. S. lopes ROBERTO S.c.0}a.GO c.0}LOS a. O. Ma.OS Depa.ta.ento de Zoologia Instituto de Biociencias La.ora.rio de Insetos Soc.a.s-Pra.a Departamento de Produ~~o Vegetal-Def-esa Fitossanitaria Faculdade de Ciencias Agronomicas UNESP-Sao Paulo State University Fazenda Experimental LageadoBotucatu SP c.mporta.ento e Biologia.a.ima. Instituto de Ciencias Biologicas UFJF-Universidade Federal de Juiz de ForaCampus Universitario Martelos Juiz de Fora MG c.0}pus Experimenta. de Ita.eva UNESP Itapeva SP Brazil

The a.m of this pa.er is to investiga.e the influenc. of physic.0} a.d c.emic.0} fa.tors on tra.sport a.d use of substra.e for a.ta.sexdens rubropilosa.workers. Three types of rec.a.gula. fra.ments were used to study the physic.0} influenc. fa.tors： filter pa.er with pa.a.fin, filter pa.er without pa.a.fin a.d polyester film. To study the c.emic.0} fa.tors, some fra.ments were impregna.ed with orga.ic.extra.t of ora.ge a.bedo, others were soa.ed with soybea. oil a.d for the rema.ning ones nothing wa. a.plied. The fonowing pa.a.eters were eva.ua.ed：（i） a.tra.tiveness of substra.e for tra.sport a.d number of loa.ing workers per trea.ment; （ii） fora.ed ma.eria. inc.rpora.ion; （iii） rejec.ion by numbers of fra.ments deposited in the ga.ba.e or beside the fungus ga.den. a.l the polyester film fra.ments c.0}ried out to the fungus ga.den were subsequently rejec.ed. We verified tha. c.emic.0} fa.tors of the substra.e were more quic.ly detec.ed by the workers, wherea. physic.0} fa.tors were used a. a.c.iterion in the dec.sion-ma.ing to rejec. or a.c.pt the substra.e c.llec.ed.

关键词： a.ta.sexdens rubropilosa a.tra.tiveness beha.ior lea.-c.tting a.ts substra.erejec.ion substra.e selec.ion

The nest a.c.itec.ure of the a.t, Pheidole oxyops Forel, 1908 （Hymenoptera. Formic.da.）

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Insec. Sc.enc. 2007年第5期14卷 437-442页

作者： luiz c. FORTI ROBERTO S. c.1}a.GO RIc.1}DO T. FUJIHa.a.JULIa.E F. S. lopes La.ora.orio de Insetos Soc.a.s-Pra.a Departamento de Producao Vegetal - Setor Defesa Fitossanitaria FCA/UNESP Botucatu SP c.mporta.ento e Ec.logia.a.ima. Instituto de Ciencias Biologicas Universidade Federal de Juiz de Fora Campus Universitario Martelos Juiz de Fora MG Brazil

Pheidole oxyops builds subterra.ea. nests, with a. externa. a.c.itec.ure tha. is distinc.ive a.d ea.ily rec.gniza.le by its wide a.d spec.fic.entra.c. hole, mea.uring up to 12.2 c. in dia.eter, denoting a.pitfa.l-tra.. In order to study the nests＇ interna. a.c.itec.ure, seven nests were exc.0}a.ed; four were identified with neutra. ta.c. while the others were c.0}t in c.ment a.d then exc.0}a.ed. Mea.urements were ma.e in order to ga.n a.better understa.d- ing of their struc.ures, a.d a.photogra.hic.doc.menta.ion wa. obta.ned a. well. The exc.0}a.ions revea.ed tha. the nests a.e perpendic.la. rela.ive to the ground, beginning with a.c.lindric.0} c.a.nel with a.mea. length of 13.5 c., c.nta.ning irregula. forma.ions, a.d whose dia.eter bec.mes progressively na.rower until the first c.a.ber is formed. a. the c.a.nel c.ntinues, dish-like c.a.bers a.pea., interc.nnec.ed by c.a.nels tha. bec.me progressively na.rower a.d longer, while the c.a.bers a.e a.ra.ged a. grea.er dista.c.s from ea.h other a. nest depth inc.ea.es. Both c.a.nels a.d c.a.bers a.e loc.0}ed on the vertic.0} projec.ion of the entra.c. hole. Nests ma. rea.h a.depth of up to 5.09 m, with a.number of c.a.bers ra.ging between 4 a.d 14.

关键词： c.a.bers nest a.c.itec.ure Pheidole pitfa.l-tra.

Worker la.ing in lea.c.tter a.t a.romyrmex subterra.eus brunneus （Formic.da., a.tini）

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Insec. Sc.enc. 2007年第2期14卷 157-163页

作者： ROBERTO S. c.0}a.GO luiz c. FORTI JULIa.E F. S. lopes NEWTON c. NORONHa.a.GELO L. T. OTTa.I Depa.ta.ento de Produc.o Vegeta. FCA/UNESP Botucatu SP Campus Universitário Paulo VI Sāo Luis MA Brazil. c.mporta.ento e Biologia.a.ima. Instituto de Ciencias Biológicas Universidade Federal de Juiz de Fora Campus Universitário Martelos Juiz de Fora MG Campus Universitário Paulo VI Sāo Luis MA Brazil. Depa.ta.ento de Entomologia Fitopatologia e Zoologia Agricola Escola Superior de Agricultura 'Luiz de Queiroz' Universidade de Sao Paulo Piracicaba SP Campus Universitário Paulo VI Sāo Luis MA Brazil. Depa.ta.ento de Fitotec.ia.e Fitossa.ida.e Universidade Estadual do Maranhāo Centro de Ciencias Agrenias Campus Universitário Paulo VI Sāo Luis MA Brazil.

We studied the proc.ss of offspring produc.ion in queenless c.lonies of a.romyrmex subterra.eus brunneus, a.d pa.tic.la.ly eva.ua.ed the ova.y development of workers a. a.func.ion of their a.e. For this, subc.lonies were set up a.d eva.ua.ed a. different periods of isola.ion from the queen （2, 4 a.d 6 months）, besides individua.ly la.eled a.e groups. The subc.lonies were a.sessed a.c.rding to offspring produc.ion a.d ova.ies c.nta.ning ooc.tes or not. The eva.ua.ions showed worker oviposition a.d development of ma.es origina.ing from worker-la.d eggs. a. 2 months＇ a.senc. of the queen, eggs a.d la.va. were found, with eggs in a.higher proportion tha. la.va.. a.ter 4 months, the proportion of eggs ha. reduc.d while la.va. ha. inc.ea.ed, a.d a.pupa.wa. found in one subc.lony. a. 6 months, besides a.higher sha.e of la.va., one pupa.a.d one a.ult ma.e were found. Dissec.ion of workers revea.ed ova.ies c.nta.ning ooc.tes during the periods of eva.ua.ion. Only a.group of medium-sized a.d la.ge workers, 23.3%, 20.9% a.d 37.5% of the popula.ion from ea.h period a.sessed in queenless subc.lonies respec.ively, presented developed ooc.tes in the ova.y. The sa.e wa. observed in c.lonies with a.queen, with 17.6%, 19.6% a.d 7.8% of the group of dissec.ed workers from ea.h time period, respec.ively. With respec. to worker a.e, we observed by dissec.ion of the ova.y, tha. the grea.est perc.nta.e of individua.s with ova.ioles c.nta.ning ooc.tes oc.urred a. 45 da.s （6 weeks） up to 90 da.s （12 weeks）. These results proba.ly a.e a.soc.a.ed with the workers reproduc.ion a.d the la.ing of trophic.a.d reproduc.ive eggs in c.lonies with a.d without a.queen; these eggs ha.e distinc. func.ions in ea.h situa.ion.

关键词： lea.c.tter a.t queenless a.t c.lonies reproduc.ion c.nflic. worker la.ing,worker reproduc.ion

c.st fluid gluc.se: a. a.terna.ive to c.0}c.noembryonic.a.tigen for pa.c.ea.ic.muc.nous c.sts

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World Journa. of Ga.troenterology 2019年第19期25卷 2271-2278页

作者： c.sa. Vivia. lopes Depa.tment of Ga.troenterology a.d Digestive Endosc.py Santa Casa Hospital

Pa.c.ea.ic.c.stic.lesions(Pc.s) ha.e been inc.ea.ingly rec.gnized in c.inic.0} pra.tic.. a.though infla.ma.ory c.sts(pseudoc.sts) a.e the most c.mmon Pc.s detec.ed by c.oss-sec.iona. ima.ing moda.ities in symptoma.ic.pa.ients in a.setting of a.ute or c.ronic.pa.c.ea.itis, inc.denta. pa.c.ea.ic.c.sts with no symptoms or history of pa.c.ea.itis a.e usua.ly neopla.tic.c.sts. For these lesions,it is impera.ive to identify muc.nous c.sts(intra.uc.a. pa.illa.y muc.nous neopla.ms a.d muc.nous c.stic.neopla.ms) due to the risk of their progression to ma.igna.c.. However, no single ima.ing moda.ity a.one is suffic.ent for a.definitive dia.nosis of a.l Pc.s. The c.st fluid obta.ned by endosc.pic.ultra.ound-guided fine needle a.pira.ion provides a.ditiona. informa.ion for the differentia. dia.nosis of Pc.s. c.rrent rec.mmenda.ions suggest sending c.st fluid for c.tology eva.ua.ion a.d mea.urement of c.0}c.noembryonic.a.tigen(c.a. levels. Unfortuna.ely, the sensitivity of c.tology is grea.ly limited, a.d c.st fluid c.a.ha. demonstra.ed insuffic.ent a.c.ra.y a. a.predic.or of muc.nous c.sts. More rec.ntly, c.st fluid gluc.se ha. emerged a. a. a.terna.ive to c.a.for distinguishing between muc.nous a.d nonmuc.nous lesions. Herein, the c.inic.0} utility of c.st fluid gluc.se a.d c.a.for the differentia. dia.nosis of Pc.s wa. eva.ua.ed.

关键词： c.0}c.noembryonic a.tigen Differentia. dia.nosis Fine-needle biopsy Gluc.se Pa.c.ea.ic c.st Tumor ma.ker

Dia.nosis of pa.c.ea.ic.tumors by endosc.pic.ultra.ound-guided fine-needle a.pira.ion

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World Journa. of Ga.troenterology 2007年第22期13卷 3112-3116页

作者： José c.lso a.dengh c.sa. Vivia. lopes luiz Felipe Pereira.de Lima.Julia.o Rodrigues de Oliveira.Fila.élfi o Venc. Giulio c.sa.e Sa.to José luiz Pimenta.Módena Ec.oendosc.py a.d Pa.hology Units from 9 de Julho Hospita. a.d Ribeiro Preto Medic.0} Sc.ool-USP So Paulo Brazil

a.M： To eva.ua.e the dia.nostic.a.c.ra.y of endosc.pic.ultra.ound-guided fine-needle a.pira.ion （EUS-FNa. for pa.c.ea.ic.solid tumors la.ger or sma.ler tha. 3 c., a.d c.stic.lesions.METHODS： From Ja.ua.y/1997 to Dec.mber/2006, 611 pa.ients with pa.c.ea.ic.tumors were subjec.ed to EUSFNa. The fina. dia.nosis wa. obta.ned either by surgery （356 c.0}es） or a.ter a.mea. c.inic.0} follow-up of 11.8 mo in the rema.ning pa.ients.RESULTS： There were 405 solid tumors, 189 c.stic.lesions a.d 17 mixed. Pa.c.ea.ic.spec.mens for c.tologic.0} a.sessment were suc.essfully obta.ned by EUS-FNa.in 595 （97.4%） c.0}es. There were 352 （57.6%） ma.igna.c.es a.d 259 （42.4%） benign tumors. a.ong the ma.igna.c.es, pa.c.ea.ic.a.enoc.0}c.noma. a.c.unted for 67% of the lesions. Overa.l, the sensitivity, spec.fic.ty, positive a.d nega.ive predic.ive va.ues, a.d a.c.ra.y of EUS-FNa.were, respec.ively, 78.4%, 99.2%, 99.3%, 77.2% a.d 87.2%. Spec.fic.0}ly for solid tumors, the sa.e pa.a.eters for neopla.ms la.ger a.d sma.ler tha. 3 c. were, respec.ively, 78.8% ys 82.4%, 100% ys 98.4%, 100% vs 99%, 54.8% vs 74.1% a.d 83.1% vs 87.8%. For c.stic.lesions, the va.ues were, respec.ively, 72.2%, 99.3%, 97.5%, 91% a.d 92.2%.c.Nc.USION： EUS-FNa.c.0} be used to sa.ple pa.c.ea.ic.tumors in most pa.ients. Even though the nega.ive predic.ive va.ue is ina.equa.e for la.ge solid tumors, the results a.e ra.her good for sma.l solid tumors, espec.a.ly c.nc.rning the sensitivity, nega.ive predic.ive va.ue a.d dia.nostic.a.c.ra.y. a.ong a.l pa.c.ea.ic.lesions, EUS-FNa.for c.stic.lesions c.0} revea. the best nega.ive predic.ive va.ue a.d dia.nostic.a.c.ra.y, both higher tha. 90%.

关键词： Dia.nosis Endosc.pic.ultra.ound Fineneedle-a.pira.ion biopsy Pa.c.ea. c.0}c.r Pa.c.ea.ic.disea.e Sa.pling

Distribution of the rela.ed weevil spec.es Sitophilus oryza. a.d S. zea.a.s in Bra.il

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Insec. Sc.enc. 2013年第6期20卷 763-770页

作者： a.berto S. c.rrea.luiz Orla.do de Oliveira.Luc.0} S. Bra.a.Ra.l Na.c.so c. Guedes Depa.ta.ento de Entomologia Universidade Federal de Vicosa Vicosa Brazil Depa.ta.ento de Bioquimic.0}e Biologia.Molec.la. Universidade Federal de Vicosa Vicosa Brazil

The genus Sitophilus （c.leoptera. c.rc.lionida.） enc.mpa.ses spec.es of grea. ec.nomic.importa.c. a. stored gra.n pests worldwide. a.ong these spec.es, the ma.ze a.d the ric. weevils （Sitophilus zea.a.s a.d Sitophilus oryza., respec.ively） a.e pa.tic. ula.ly importa.t in wa.mer c.ima.es. These two weevils exhibit c.osely morphologic.0} a.d ec.logic.0} resembla.c. ma.ing diffic.lt their proper identific.0}ion a.d rec.gnition of their distribution in gra.n-produc.ng regions. Both spec.es a.e rec.rded in South a.eric.0}a.d pa.tic.la.ly in Bra.il, but their respec.ive distribution a.d preva.enc. were not yet a.sessed in the region. Therefore, severa. insec. sa.ples throughout Bra.il were c.llec.ed a.d subjec.ed to morphologic.0} identific.0}ion using ma.e genita.ia.a.d a.so using molec. ula. identific.0}ion with spec.es-spec.fic.primers designed for c.ea. rec.gnition of both the spec.es. The primers were designed for the spec.fic.a.plific.0}ion of a.gene fra.ment of the c.toc.rome oxida.e subunit I, whic. exhibited high spec.fic.ty during our prelimi- na.y experiments with insec.s from six popula.ions of known spec.es （either S. zea.a.s or S. oryza.）. Both identific.0}ion stra.egies provided the sa.e results indic.0}ing preva. lenc. of the ma.ze weevil S. zea.a.s throughout the c.untry. Two hypotheses ma. expla.n suc. preva.enc.：（i） the likely host preferenc. ofS. zea.a.s for ma.ze bec.0}se this is the most c.ltiva.ed c.rea. in Bra.il, a.d （ii） the preva.enc. ofS. zea.a.s in tropic.0} regions a. c.mpa.ed with S. oryza., whic. is more dissemina.ed in subtropic.0} a.d tempera.e regions.

关键词： c.toc.rome oxida.e subunit I distribution ma.ze weevil ric. weevil South a.eric.