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Correction of failure in antenna array us.ng matrix pencil tech.ique

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Ch.nes. Ph.s.cs.B 2017年第6期26卷 491-498页

作者： s.U Kh.n M K A Rah.m Advanced RF & Microwave Res.arch.Group Department of Communication Engineering Faculty of Electrical Engineering Universiti Teknologi Malaysia 81310 Skudai Johor Malaysia

In th.s.paper a non-iterative tech.ique is.developed for th. correction of faulty antenna array bas.d on matrix pencil tech.ique（MPT）. Th. failure of a s.ns.r in antenna array can damage th. radiation power pattern in terms.of s.delobes.level and nulls. In th. developed tech.ique, th. radiation pattern of th. array is.s.mpled to form dis.rete power pattern information s.t. Th.n th.s.information s.t can be arranged in th. form of h.nkel matrix（h.） and execute th. s.ngular value decompos.tion（s.D）. By removing nonprincipal values. we obtain an optimum lower rank es.imation of h.. Th.s.lower rank matrix corres.onds.to th. corrected pattern. Th.n th. propos.d tech.ique is.employed to recover th. weigh. excitation and pos.tion allocations.from th. es.imated matrix. Numerical s.mulations.confirm th. efficiency of th. propos.d tech.ique, wh.ch.is.compared with.th. available tech.iques.in terms.of s.delobes.level and nulls.

关键词： array correction low rank es.imation matrix pencil tech.ique s.ngular value decompos.tion

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地球物理用电磁理论

地球物理用电磁理论

Rh.ological Regime of th. Upper Mantle beneath.th. Taiwan s.rait and Its.Tectonic s.gnificance

作者： s.h.·沃德(s.h. Ward)

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Acta Geologica s.nica(Englis.0}Edition) 1995年第3期69卷 259-271,340页

作者： h.W.GreenⅡ U яivets.ty of California RiuersideC A 92521U.S.A.

Th.s.paper deals.with.deformation textures.and fabrics.of mantle-derived xenolith. and dis.ocation micros.ructures.of olivine in th. upper mantle in th. Pengh. Is.ands. Taiwan. According to th. calculation of th. ch.mical compos.tion of xenolith.minerals.(pyroxene), th. equilibrium temperatures.and pres.ures.were 986-1116@ and 1.50-2.60 GPa, res.ectively. Deformation events.in th. upper mantle may fall into th.ee s.quences. (1) uniform s.eady-s.ate flow deformation with.h.gh.temperatures.and low s.res.es. (2) s.0}ar flow deformation with.h.gh.temperatures.and relatively h.gh.s.res.es.on diapiric margins.of th. upper mantle, and (3) extraction deformation of {110} glide bands.with.low temperatures.and h.gh.s.rain rates. Deformation events.and th.rmal s.ructure of th. upper mantle in th. s.udy area s.0}w th.t eas.ern Fujian and th. Pengh. Is.ands.are ch.racterized by very s.milar rh.ological properties.of th. upper mantle. Volcanis. of bas.lts.in th. Pengh. Is.ands.is.related to h.t s.ots.of th. upper mantle under neath.th. Taiwan s.rait, and diapiris. and upwelling of th. upper mantle are th. dominant factors.res.ons.ble for rifting of th. continental margins.in eas.ern Ch.na.

关键词： mantle-derived xenolith h.gh.temperature creep rh.ology of th. upper mantle rifting Pengh. Is.ands

Properties.of Cas. h.duminium/Corundum Particulate Compos.tes

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Journal of Materials.s.ience & Tech.ology 1995年第3期11卷 171-175页

作者： K.h. W. s.ah.Dept. of Mech.nical Engineering, National Univers.ty of s.ngapore, 10 Kent Ridge Cres.ent, s.ngapore 0511)R.s.Kulkari and s.C.s.0}rma (Dept. of Mech.nical Engineering, R.V.College of Engineering, Mys.re Road, Bangalore-560-059, Karnataka, Ind National Univ of s.ngapore Singapore Singapore

Th.s.paper reports.s.me res.lts.obtained in an inves.igation to s.e h.w increas.ng th. corundum dis.ers.id content from o% to 7% in a matrix of h.duminium alloy affects.th. tens.le and compres.ive s.rength., th. h.rdnes. and th. cas.ing ch.racteris.ics.of th. compos.te. Th. res.lts.s.0}w th.t as.th. corundum content is.increas.d, ultimate tens.le s.rength.(UTs.- compres.ive s.rength.and h.rdnes. increas. remarkably, wh.reas.fluidity of th. molten compos.te during cas.ing drops.s.gnificantly. It was.found th.t jus. a minute amount of corundum is.s.fficient to caus. a fairly large ch.nge in th. mech.nical properties.and th. fluidity of th. molten *** drop in cas.ability is.one of th. reas.ns.wh. adding corundum beyond 7 percent is.not recommended. If oth.r factors.are kept cons.ant, th. fluidity is.s.en to s.igh.ly improve if th. pouring temperature of th. molten metal were increas.d from 670 to 710℃

关键词： Cas. Properties.of Cas. h.duminium/Corundum Particulate Compos.tes As.

Beef h.ifer fertility: importance of management practices.and tech.ological advancements

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Journal of Animal s.ience and Biotech.ology 2021年第1期12卷 110-121页

作者： s.rah.E.Moorey Fernando h.Bias. Department of Animal s.ience University of TennesseeKnoxvilleTNUSA Department of Animal and Poultry s.iences Virginia Polytechnic Institute and State University175 West Campus DriveBlacksburgVA 24061USA.

Th. development of replacement h.ifers.is.at th. core of cow-calf beef production s.s.ems. In 2020, th. Us.A,National Agricultural s.atis.ics.s.rvice reported 5.771 million beef h.ifers. 500 pounds.and over, are under development for cow replacement. A compilation of data from s.veral s.udies.indicate th.t between 85% and 95% of th.s. h.ifers.will become pregnant in th.ir firs. breeding s.as.n. s.veral th.us.nds.of h.ifers.being rais.d for replacement may not deliver a calf on th.ir firs. breeding s.as.n and res.lt in economic los.es.to cow-calf producers. Many management procedures.h.ve been developed to maximize th. reproductive potential of beef h.ifers. s.ch.approach.s.include, but are not limited to th. following: nutritional management for controlled weigh. gain, identification of reproductive maturity by ph.s.ological and morph.logical indicators. and th. implementation of an es.rous.s.nch.onization *** implementation of management s.rategies.h.s.important pos.tive impact(s. on th. reproductive efficiency of *** are limitations. h.wever, becaus. s.me h.ifers.deemed ready to enter th.ir firs. breeding s.as.n do not become pregnant. In parallel, genetic s.lection for fertility-related traits.in beef h.ifers.h.ve not promoted major genetic gains.on th.s.particular area, mos. likely due to low h.ritability of female fertility traits.in cattle. Tech.ologies.s.ch.as.antral follicle counting, DNA genotyping and RNA profiling are being inves.igated as.a means.to aid in th. identification of h.ifers.of low fertility potential. To date, many polymorph.s.s.h.ve been as.ociated with.h.ifer fertility, but no DNA markers.h.ve been identified acros. h.rds. Antral follicle count is.an indication of th. ovarian res.rve and is.an indicator of th. reproductive h.alth.of a h.ifer. We h.ve been working on th. identification of trans.riptome profiles.in h.ifers.as.ociated with.pregnancy outcome. Our current inves.igations.integrating protein-coding trans.ript abu

关键词： Beef cattle Cow-calf Genomics Infertility

s. of s.reptococcus.pneumonia Circulating in Burkina Fas. before th. Introduction of PCV-13, 2013

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Advances.in Microbiology 2023年第5期13卷 237-248页

作者： Kambiré Dinanibè Tamboura Mamadou Ouédraogo Oumarou Tondé Is.a Ouédraogo W. h. Gautier s.nou Mah.moudou Zouré Abdou Azaque Compaoré Rebeca s.gna Tani s.ubeiga R. s. Th.oph.le Zida s.lvie Aké Flavien Abdoul-s.lam Ouédraogo s.ngaré Las.ana Méda Is.ïe Kouanda s.ni Ouédraogo-Traoré Ras.ata Centre h.s.italier Univers.taire Pédiatrique Ch.rles.De Gaulle Ouagadougou Burkina Faso Ins.itut de Rech.rch. en s.iences.de la s.nté Ouagadougou Burkina Faso Davycas.International Ouagadougou Burkina Faso Centre h.s.italier Univers.taire Yalgado Ouédraogo Ouagadougou Burkina Faso Centre h.s.italier Univers.taire s.non s.urô Bobo-Dioulasso Burkina Faso Direction Générale de la s.nté Publique Ouagadougou Burkina Faso

Introduction: Burkina Fas. experiences.regular cas.s.of s.reptococcus.pneumoniae meningitis. As.part of th. s.rategy to reduce cas.s.of meningitis. th. 13-valent pneumococcal conjugate vaccine (PCV-13) h.s.been introduced in th. Expanded Programme on Immunis.tion (EPI). Des.ite th.s. efforts. th.re are s.me cas.s.of pneumococcal meningitis.including both.vaccine and non-vaccine s.rotypes. Th. objective of th.s.s.udy was.to des.ribe th. pneumococcal s.quence types.(s.) circulating in Burkina Fas. before th. introduction of th. 13-valent pneumococcal conjugate vaccine (PCV-13). Meth.ds. It was.a des.riptive cros.-s.ctional s.udy th.t took place from 27th.October 2013 to 7th.January 2014. s. pneumoniae s.rains.were collected in Burkina Fas. and Multi Locus.s.quence Typing (MLs.) was.performed at th. Pneumococcal Laboratory at th. Centers.for Dis.as. Control and Prevention (CDC) in th. Us. (United s.ates.of America). MLs. cons.s.s.of 4 s.eps. amplification, purification, s.quencing and interpretative reading of th. res.lts. Th. amplification us.d 7 primers.cons.s.ing of s.quences.of aroe, gdh. gki, recP, s.i, xpt, ddl genes. Res.lts. Of 37 s.rains.tes.ed, 10 s.rotypes.were identified. s.rotype 1 was.prevalent in 48.7% (18/37) followed by s.rotype 25F in 10.8% (4/37). s.rotypes.5 and 12F/12A/12B/44/46 were 8.1% (3/37) each. s.rotype 1 contained 5 s.s.including s.303 24.3% (9/37), s.217 8.1% (3/37) and s.618 8.1% (3/37);followed by s.rotype 25F with.s.105 10.8% (4/37), s.rotype 5 with.s.289 8.1% (3/37) and s.rogroup 12F/12A/12B/44/46 with.s. 989 8.1% (3/37). Conclus.on: Pneumococci are ch.racteris.d by th.ir great variability both.in number of s.rotypes.and in s. with.n th. s.me s.rotype. Th.s. 10 s.rotypes.h.ve been identified. Als., with.n s.rotype 1, 5 different s.s.h.ve been des.ribed. Th.s. data indicate th. complexity of th. pneumococcus.wh.ch.is.s.rongly involved in purulent bacterial meningitis.at national level. Th.s.requires.continuous.s.rveillance of pneumococc

关键词： s.reptococcus.pneumoniae Burkina Fas. PCV-13 s.quence Types

h.rdnes., Wear Res.s.ance and Fracture Tough.es. of Cas. h.duminium/Corundum Particulate Compos.tes

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Journal of Materials.s.ience & Tech.ology 1996年第5期12卷 357-360页

作者： K.h.W.s.ah.Dept. of Mech.nical Engineering, National Univers.ty of s.ngapore, 10 Kent Ridge Cres.ent, s.ngapore 119260)R.s.Kulkarni and s.C.s.0}rma (Dept. of Mech.nical Engineering, R.V.College of Engineering, Mys.re Road, Bangalore-560-059, Karnataka, Ind Dept. of Mech.nical Engineering National University of Singapore 10 Kent Ridge Crescent Singapore 119260 Singapore Dept. of Mech.nical Engineering R.V.College of Engineering Mysore Road Bangalore-560-059 Karnataka India Dept. of Mech.nical Engineering SJCE Mysore India

Th.s.paper reports.s.me res.lts.obtained in an inves.igation to s.e h.w increas.ng th. corundum dis.ers.id content from 0% to 7% in a matrix of as.cas. and wrough. h.duminium alloy affects.th. h.rdnes.. wear res.s.ance and fracture tough.es. of th. compos.te. Th. res.lts.s.0}w th.t as.th. corundum content is.increas.d, th. h.rdnes. and th. wear res.s.ance increas. remarkably,wh.reas.th. fracture tough.es. drops.s.gnificantly. It was.found th.t Jus. a minute amount of corundum is.s.fficient to caus. a fairly large ch.nge in th.s. mech.nical properties. Th. h.rdnes. of th. material is.als. affected s.gnifIcantly by th. aging time. Moreover, if oth.r factors.are kept cons.ant, h.t extrus.on improves.both.its.h.rdnes. and its.wear res.s.ance. wh.reas.th. fracture tough.es. is.decreas.d

关键词： Wear Res.s.ance and Fracture Tough.es. of Cas. h.duminium/Corundum Particulate Compos.tes Book Cas. h.rdnes.

Development of non-s.0}inkable ceramic compos.tes.for us. in h.gh.power microwave tubes

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International Journal of Minerals.Metallurgy and Materials 2019年第4期26卷 516-522页

作者： N.Dandapat s.Gh.s. Bioceramics.and Coating Divis.on CSIR-Central Glass and Ceramic Research Institute

Al_2O_3–CaO–s.C-bas.d ceramic compos.tes.with.four different compos.tions.were s.ntered at 1700℃ for 3 h.in an air furnace. Th. ph.s. analys.s. micros.ructural ch.racterization, and elemental compos.tion determination of th. developed compos.tes.were performed by X-ray diffraction(XRD), field-emis.ion s.anning electron micros.opy(FEs.M), and energy-dis.ers.ve X-ray(EDAX) analys.s. res.ectively. Th. s.0}inkage, th.rmal properties. and electrical res.s.ivity of th. compos.tes.were als. s.udied. Th. experimental res.lts.s.0}wed th. effects.of adding s.licon carbide and calcia to alumina on th. th.rmal, electrical, and s.0}inkage properties.of th. res.ltant compos.tes. Among th. four inves.igated ceramic compos.tes. th. one compos.d of 99 wt% alumina, 0.5 wt% CaO, and 0.5 wt% s.C exh.bited th. bes. ch.racteris.ics.for us. as.a potting material in a dis.ens.r cath.de of a microwave tube. Th. material exh.bited s.igh. expans.on ins.ead of s.0}inkage during drying or firing. Oth.r properties.of th. compos.te powder, s.ch.as.its.th.rmal properties.and electrical res.s.ivity, were comparable to th.s. of a commercial alumina powder.

关键词： Al2O3-CaO-s.C compos.te expans.on potting material dis.ens.r cath.de microwave tube

Non-s.andard tes.s.for proces. control in ch.mically bonded s.nds

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Ch.na Foundry 2016年第1期13卷 59-66页

作者： s.Ramrattan Department of Engineering Des.gn Manufacturing and Management Systems Western Michigan University

Ch.mically bonded s.nd cores.and molds.are more commonly referred to as.precis.on s.nd s.s.ems.in th. h.gh.production automotive powertrain s.ctor. Th.ir beh.vior in contact with.molten metal can lead to cas.ing defects. Cons.quently, th. interaction is.of great interes. and an important part of metal cas.ing tech.ology. Th. American Foundry s.ciety(AFs. s.nd tes.ing is.bas.d on ph.s.cal, mech.nical, th.rmal and ch.mical properties.of th. s.nd s.s.em. Foundry engineers.h.ve long known th.t certain AFs.s.nd tes.s.provide limited information regarding control of molding and cas.ing quality. Th. inadequacy is.due to th. fact th.t s.nd cas.ing proces.es.are inh.rently th.rmo-mech.nical, th.rmo-ch.mical and th.rmo-ph.s.cal. Non-s.andard foundry s.nd tes.ing h.s.proven us.ful for laboratory meas.rement of th.s. ch.racteris.ics.in foundry s.nd us.ng a dis.-s.0}ped s.ecimen. s.milarly, th. equivalent dis.-s.0}ped s.ecimens.are us.d for cas.ing trials. In order to accomplis.0}near-net-s.0}pe cas.ing with.minimal defects. it is.neces.ary to unders.and both.th. properties.of th. s.nd s.s.em, as.well as.th. interface of molten metal wh.n different binders. additives.and/or refractory coatings.are us.d. Th. meth.dology for th. following non-s.andard ch.mically bonded s.nd tes.s.is.des.ribed:(1) dis. trans.ers.;(2) impact;(3) modified permeability;(4) abras.on;(5) th.rmal dis.ortion;(6) quick los. on ignition. Th. data related to th. non-s.andard s.nd tes.s.were analyzed and interpreted. Th. tes. res.lts.indicate th.t th.re is.relatively lower tes.-to-tes. variability with.th. dis.-s.0}ped s.ecimens. Th. non-s.andard tes.s.were able to dis.riminate between th. ch.mically bonded polyureth.ne cold box s.nd s.ecimens. Furth.r s.udies.s.0}uld be conducted on various.oth.r s.nd and binder s.s.ems.as.well as.on different s.ecimen th.cknes.es.

关键词： ch.mically bonded s.nd permeability tes. th.rmal dis.ortion tes. los. on ignition