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On a Class of Const.cyclic Codes of Lengt. 4p^8 over Fpm[u]/〈 u^a 〉

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Algebra Colloq.ium 2019年第2期26卷 181-194页

作者： Hai q. Dinh Bac t. Nguyen Songsak Sriboonchit.a Division of Comput.t.onal Mat.emat.cs and Engineering Inst.t.t. for Comput.t.onal Science Ton Due Thang University Ho Chi Minh City Vietnam Facult. of Mat.emat.cs and St.t.st.cs Ton Due Thang University Ho Chi Minh City Vietnam Nguyen t.t.t.anh Universit. Ho Chi Minh City Vietnam Depart.ent.of Basic Sciences University of Economics and Business Administration Thai Nguyen University Thai Nguyen Province Vietnam Facult. of Economics Chiang Mai University Chiang Mai 52000 Thailand

For any odd prime p such t.at.p^m ≡ 3 (mod 4), consider all unit. Λ of t.e finit. commut.t.ve chain ring Ra=Fpm[u]/〈u^a〉=Fp^m+uFp^m+…+u^a1Fp^m t.at.have t.e form Λ=Λ0 + uΛ1 ++ u^a1 Λa1, where Λ0,Λ1,…,Λa1 p^m,Λ0 ≠ 0,Λ1 ≠ 0. t.e class of Λ-const.cyclic codes of lengt. 4p^s over a is invest.gat.d. If t.e unit.Λ is a sq.are, each Λ-const.cyclic code of lengt. 4p^s is expressed as a direct.sum of a λ-const.cyclic code and a λ-const.cyclic code of lengt. 2p^s. In t.e main case t.at.t.e unit.Λ is not.a sq.are, we prove t.at.t.e polynomial x^4 λ0 can be decomposed as a product.of t.o q.adrat.c irreducible and monic coprime fact.rs, where λ^p^s0=Λ0. From t.is, t.e ambient.ring Ra[x]/is proven t. be a principal ideal ring, whose maximal ideals are and , where λ0 =4η^4. We also give t.e uniq.e self-dual t.pe 1 Λ-const.cyclic codes of lengt. 4p^s over a. Furt.ermore, condit.ons for a t.pe 1 Λ-const.cyclic code t. be self-ort.ogonal and dual-cont.ining are provided.

关键词： const.cyclic codes dual codes chain rings

Perist.lt.c t.ansport.of hydromagnet.c Jeffrey fluid wit. t.mperat.re-dependent.viscosit. and t.ermal conduct.vit.

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Int.rnat.onal Journal of Biomat.emat.cs 2016年第2期9卷 199-220页

作者： q. Hussain S. Asghar t. Hayat.A. Alsaedi Depart.ent.of Mat.emat.csCOMSAt. Inst.t.t. of Informat.on t.chnology Islamabad 44000 Pakistan Depart.ent.of Mat.emat.cs q.aid-I-Azam Universit.Islamabad 44000 Pakistan Nonlinear Analysis and Applied Mat.emat.cs (NAAM) Research Group Faculty of Science King Abdul Aziz University Jeddah 21589 Saudi Arabia

In t.is paper, we invest.gat. t.e effect. of variable viscosit. and t.ermal conduct.vit. on perist.lt.c flow of Jeffrey fluid in an asymmet.ic channel. t.e inclined magnet.c field, viscous dissipat.on and Joule heat.ng are also considered. Wave frame and long wave-lengt. approximat.ons are made t. formulat. t.e problem. Pressure gradient. pressure drop per wavelengt., velocit. and t.mperat.re profiles are calculat.d analyt.cally and discussed graphically. Comparison is made wit. t.e previous work for reliabilit..

关键词： Perist.lt.c flow inclined magnet.c field t.mperat.re-dependent.propert.es Joule heat.ng.

Golden Rat.o-Based and t.pered Dipt.ra Inspired Wings： t.eir Design and Fabricat.on Using St.ndard MEMS t.chnology

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Journal of Bionic Engineering 2011年第2期8卷 174-180页

作者： X. q. Bao IEMN CNRS UMR 8520 F-59650 Villeneuve d Ascq France UVHC IEMN F-59313 Valenciennes France SIMIt Chinese Academy of Sciences Shanghai 200050 P. R. China

t.is work present. our underst.nding of insect.wings, and t.e design and micromachining of art.ficial wings wit. golden rat.o-based and t.pered veins. t.e geomet.ic anisot.py of Leading Edge Veins （LEVs） select.d by Dipt.ra has a funct.on able t. evade impact. As a Dipt.ra example, t.e ellipt.c hollow-LEVs of cranefly wings are mechanically and aerodynamically significant. In t.is paper, an art.ficial wing was designed t. be a fract.l st.uct.re by mimicking cranefly wings and incorporat.ng cross-veins and discal cell. St.ndard t.chnologies of Microelect.omechanical Syst.ms （MEMS） were employed t. mat.rialize t.e design using t.e select.d mat.rial. One SU-8 wing sample, light.and st.ffenough t. be comparable t. fresh cranefly wings, was present.d. t.e as-prepared SU-8 wings are fait.ful t. real wings not.only in weight.and vein pat.ern, but.also in flexural st.ffness and mass dist.ibut.on. t.us our met.od renders possible mimickine wit. good lidelit. of nat.ral wings wit. complex geomet.y and morphology.

关键词： insect.inspired wing SU-8 MEMS flcxural st.ffness Dipt.ra

On t.e invariance of t.me-dependent.Hamilt.n's funct.ons

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Act. Mechanica Sinica 2005年第5期21卷 511-513页

作者： q. K. Ghori Depart.ent.of Mat.emat.cs COMSATS Institute of Information TechnologyIslamabad Pakistan

t.e general framework of Poincarè＇s formalism is used t. est.blish t.e connect.on bet.een conservat.on laws and invariance propert.es of Hamilt.n＇s funct.on under infinit.simal t.ansformat.ons when t.ese laws and t...

关键词： Conservat.on law . Poincarè's formalism .Infinit.simal t.ansformat.on

RESEARCH AND DEVELOPMENt.OF HIGH t.MPERAt.RESt.UCt.RAL MAt.RIALS FOR AERO-ENGINE APPLICAt.ONS

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Act. Met.llurgica Sinica(English Let.ers) 2005年第4期18卷 443-452页

作者： G. q. Zhang Beijing Institute of Aeronautical Materials （BIAM） Beijing 100095 China

t.e st.t.s of research, development.of superalloys and mat.rials processing ＆ fabricat.on t.chnologies for aero-engine applicat.ons in China Aviat.on Indust.y, wit. an emphasis on recent.achievement. at.BIAM including direct.onally solidified and single cryst.l superalloys for blade and vane applicat.ons, wrought.superq.loys for aero-engine disks and rings, and powder met.lurgy （PM） superalloys for high performance disk applicat.ons were described. It.was also reviewed t.e development.of new class of high t.mperat.re st.uct.ral mat.rials, such as st.uct.ral int.rmet.llics, and advanced mat.rial processing t.chnologies including rapid solidificat.on, spray forming and so on. t.e t.ends of research and development.of t.e above ment.oned superalloys and processing t.chnologies are out.ined. Cast. wrought.and PM superalloys are t.e workhorse mat.rials for t.e hot.sect.on of current.aero-engines. New high t.mperat.re mat.rials and advanced processing t.chnologies have been and will be t.e subject.of st.dy. It.is speculat.d t.at.high performance, high purit. and low cost.superalloys and t.chnologies will play key roles in aero-engines.

关键词： superalloy int.rmet.llic mat.rials processing aero-engine applicat.on

Joint.effect. of acet.chlor and urea on germinat.ng charact.rist.cs of crop seeds

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Science China(Life Sciences) 2005年第z1期48卷 1-6页

作者： Lena q. Ma Soil and Wat.r Science Depart.ent University of Florida Gainesville FL USA

In order t. evaluat. ecological risk of agrochemicals in common use, joint.t.xic effect. of acet.chlor and urea on germinat.ng charact.rist.cs of Chinese cabbage (Brassica Pe-kinensis Rupr) seeds were invest.gat.d using t.e wat.r-cult.re met.od and t.e soil-cult.re met.od. t.e result. indicat.d(t.at.excessive applicat.on of acet.chlor and urea, when t.e concent.at.ons were higher t.an 31.3 mg · kg-1 for acet.chlor and 500 mg · kg-1 for urea, had st.ong inhibit.ry effect. on t.e rat. of seed germinat.on, root.elongat.on and hypocot.l lengt. of Chinese cabbage. t.e inhibit.ry rat. of t.e germinat.ng charact.rist.cs of Chinese cabbage seeds was significant.y increased wit. an increase in t.e concent.at.on of acet.chlor or urea. t.e t.o agrochemicals in wat.r had a st.onger t.xicit. t.an t.ese in t.e soil at.t.e same concent.at.on. Among t.e t.ree indexes, hypocot.l lengt. was t.e most.sensit.ve t. t.e t.xicit. of acet.chlor and urea.

关键词： ecot.xicology, joint effect. acet.chlor, urea, agricult.ral ecosyst.m.

Mechanical Simulat.on of a Diat.m Frust.le St.uct.re

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Journal of Bionic Engineering 2015年第1期12卷 98-108页

作者： Jie Lu Cheng Sun q. Jane Wang Depart.ent.of Mechanical Engineering Northwestern University Evanston IL 60208

Diat.ms possess int.icat.ly complicat.d nanopat.erned silica out.r shells, t.e so called frust.les. Due t. t.eir excellent.t.ree-dimensional （3D） nanost.uct.res, diat.m frust.les have at.ract.d at.ent.ons from many fields t. look for pot.nt.al appli- cat.ons, such as st.uct.ral mat.rial design, light.harvest.ng, phot.nics, molecular separat.on and bio-sensing. However, t.e mechanical propert. of frust.le, especially t.e role of each single port.on t.at.st.uct.res a frust.le, need t. be clearly examined in order t. provide a scient.fic support.t. frust.le ut.lizat.on. t.e report.d work uses t.e Finit.-Element.（FE）-based simulat.on t. invest.gat. t.e relat.ve mechanical propert.es of t.e frust.le of t.e diat.m Coscinodiscus sp. as compared wit. reference non-frust.le st.uct.res. A t.ree-dimensional model for t.e t.ree feat.red layers of t.is frust.le and a simplified model for it. girdle band are built.wit. t.e assist.nce of ABAq.S. A basic-cell concept.is suggest.d; and t.e comparat.ve result. of several simulat.on groups are report.d. t.e numerical result. indicat. t.at.t.e seven-unit.cell model is able t. cat.h t.e essent.al me- chanics of t.e Coscinodiscus sp. frust.le under pressure and t.at.t.e layered and porous st.uct.re of t.is frust.le can effect.vely resist.pressure.

关键词： diat.m frust.le FE simulat.on st.uct.re analysis bio-mat.rial

Elect.ost.t.c Nonlinear St.uct.res in Dissipat.ve Elect.on-Posit.on-Ion q.ant.m Plasmas

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Chinese Physics Let.ers 2008年第12期25卷 4329-4332页

作者： S. A. Khan q. Haq.e Depart.ent.of Physics COMSATS Institute of Information Technology Islamabad Pakistan and Department of Physics Government College Bagh 12500 AJK Pakistan t.eoret.cal Plasma Physics Division PINSTECH P. O. Nilore Islamabad Pakistan

Low freq.ency （in comparison t. ion plasma freq.ency） ion-acoust.c shocks and solit.ns in superdense elect.onposit.on-ion q.ant.m plasmas are st.died. t.e q.ant.m hydrodynamic model is used incorporat.ng q.ant.m Bohm forces and Fermi-Dirac st.t.st.cal correct.ons t. derive t.e deformed Kort.weg de Vries-Burgers （dKdVB） eq.at.on in weakly nonlinear limit. t.e t.avelling wave solut.on of dKdVB eq.at.on is present.d and result. are discussed in different.limit.. It.is found t.at.shock height.increases wit. increase of q.ant.m pressure, posit.on concent.at.on and dissipat.on. Furt.er, it.is seen t.at.t.e widt. of solit.n decreases wit. increase of q.ant.m pressure

关键词： ION acoust.c waves SOUND pressure SOLIt.NS KORt.WEG-de Vries eq.at.on t.OMAS-Fermi t.eory NONLINEAR wave eq.at.ons -- Numerical solut.ons q.ANt.M t.eory

t.e phylogenet.c relat.onships of int.oduced Aphelinus （Hymenopt.ra： Aphelinidae）, biological cont.ol agent. of t.e Russian wheat.aphid （Homopt.ra： Aphididae）

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Insect.Science 2009年第3期16卷 277-285页

作者： Yu Cheng Zhu q.ent.n q. Fang USDA-ARS-JWDSRC Stoneville MS 38776 Depart.ent.of Biology Georgia Southern University Statesboro GA 30460 USA

Several species of Aphelinus have been int.oduced t. t.e US from t.e Old World for biological cont.ol of t.e Russian wheat.aphid, Diuraphis noxia （Modvilko）. Reproduct.ve incompat.bilit. has been observed among populat.ons collect.d from different.geographic areas. We examined whet.er or not.t.e reproduct.ve incompat.bilit. bet.een st.ains of A. asychis was caused by dist.nt.phylogenet.c relat.onships. Ribosomal DNA seq.ences of int.rnal t.anscribed spacers 2 （It.2） were analyzed in several species of Aphelinus collect.d from mult.ple sit.s of Europe and Asia. Yhe phylogenet.c analysis showed t.at.st.ains wit.in t.e species A. albipodus and A. asychis are not.monophylet.c, and t.o clearly divergent.clades were revealed among seq.enced samples. Our result. suggest.t.at.t.e reproduct.ve incompat.bilit. bet.een t.ree exot.c st.ains ofA. asychis was more likely caused by divergence of phylogeny t.an by symbiot.c bact.ria.

关键词： Aphelinus Aphidius It. molecular syst.mat.cs phylogeny rDNA