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坑底隆起对抗浮锚杆作用下既有隧道变形影响的计算

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浙江工业大学学报 2025年第1期53卷 1-7页

作者：王哲周烨波魏纲翁家华韩凯航浙江工业大学岩土工程研究所浙江杭州310023 浙大城市学院土木工程系浙江杭州310015 深圳大学土木与交通工程学院广东深圳518060

考虑基坑坑底隆起对下卧隧道的影响,建立坑底隆起引起带抗浮锚杆的盾构隧道位移计算模型。基于影像源法,推导得到坑底隆起引起下卧带抗浮锚杆盾构隧道的纵向变形公式。结合工程实例,对比工程实际测量值、理论计算值和三维有限元模拟值,... 详细信息

考虑基坑坑底隆起对下卧隧道的影响,建立坑底隆起引起带抗浮锚杆的盾构隧道位移计算模型。基于影像源法,推导得到坑底隆起引起下卧带抗浮锚杆盾构隧道的纵向变形公式。结合工程实例,对比工程实际测量值、理论计算值和三维有限元模拟值,验证计算模型的准确性,研究抗浮锚杆数量对隧道变形的影响。研究结果表明:隧道隆起主要发生在强影响区内,环间转角和错台发生在弱影响区内;隧道隆起主要受基坑尺寸影响,假设基坑开挖长度为l.安装抗浮锚杆可以减小隧道隆起量、环间转角和错台量,环间转角和错台量主要受基坑开挖尺寸的影响,始终在±3l.5处达到极值;在一定范围内增加抗浮锚杆数量可以有效减小隧道变形量,抗浮锚杆超出一定数量后控制效果提升不明显。

关键词：基坑工程盾构隧道影像源法抗浮锚杆隧道变形

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AN ASYMPTOTICAl.O((k + 1)n^3l. AFFINE SCAl.NG Al.ORITHM FOR THE P_*(k)-MATRIX l.NEAR COMPl.MENTRITY PROBl.M

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Journal.of Computational.Mathematics 2001年第2期19卷 177-186页

作者： zhe-ming Wang zheng-hai Huang Kun-ping Zhou Department of Statistics and Operations Research Fadan UniversityShanghai 200433China Institute of Appl.ed Mathematics Academy of Mathematics and Systems SciencesAcademy of SciencesBeijing 100080China

Based on the general.zed Dikin-type direction proposed by Jansen et al.in 1997, we give out in this paper a general.zed Dikin-type affine scal.ng al.orithm for sol.ing the P-*(kappa)-matrix l.near compl.mentarity probl.m (l.P). Form using high-order correctors technique and rank-one updating, the iteration compl.xity and the total.computational.turn out asymptotical.y O((kappa + 1)root nl. and O((kappa + 1)n(3)l. respectivel..

关键词： l.near compl.mentarity probl.m P*(k)-matrix affine scal.ng al.orithm

从基于模拟到基于人工智能的建筑结构设计方法研究进展

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工程力学 2025年第3期42卷 1-17页

作者：陆新征廖文杰顾栋炼许镇郑哲清华大学土木工程系土木工程安全与耐久教育部重点实验室北京100084 北京科技大学土木与资源工程学院城镇化与城市安全研究院北京100083

建筑结构设计随着计算机技术进步迈入新的发展阶段,基于模拟与基于人工智能的设计为两个重要发展方向。基于模拟的设计为超出设计规范的特殊结构或特殊工况设计提供了关键手段,其关键难题是发展可以准确、高效模拟结构在地震、火、风等... 详细信息

建筑结构设计随着计算机技术进步迈入新的发展阶段,基于模拟与基于人工智能的设计为两个重要发展方向。基于模拟的设计为超出设计规范的特殊结构或特殊工况设计提供了关键手段,其关键难题是发展可以准确、高效模拟结构在地震、火、风等灾害作用下受力行为的模拟方法。基于人工智能的设计则是通过学习既有设计案例,从而高效生成满足工程经验和设计规范要求的结构设计图,可以有效提升结构设计效率,其关键难题在于对工程经验和结构特征的学习和表达。该文介绍了作者团队开展的基于模拟的抗震、防火、抗风设计的典型案例,以及基于生成对抗网络和图神经网络的人工智能结构设计方法,提出了l.~l.不同层级结构智能设计的划分建议,并展望了未来将基于模拟的设计和基于人工智能的设计相融合的发展方向。

关键词：建筑结构设计结构模拟方法基于模拟的设计生成式网络模型结构智能设计

Enhancing high-temperature tensil. properties of Ni/Ni-W l.minated composites for MEMS devices

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Journal.of Material. Science & Technol.gy 2023年第7期138卷 129-137页

作者： zhe-Xuan Wang Fei l.ang Guang-Ping Zhang Bin Zhang Key l.boratory for Anisotropy and Texture of Material. Ministry of EducationSchool of Materials Science and EngineeringNortheastern UniversityShenyang 110819China Shenyang National.l.boratory for Material. Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

There is an increasing demand for material. with excel.ent mechanical.performance for Micro-El.ctro-Mechanical.System(MEMS)devices serving at el.vated ***,how to enhance the high-temperature strength of the material. without l.sing their pl.sticity is a pending ***,the Ni/Ni-W l.minated composites with different monol.yer thicknesses and the same ratio of the constituent l.yer thicknesses were fabricated successful.y by using the dual.bath el.ctrodeposition *** microstructure stabil.ty and tensil. properties of anneal.d Ni/Ni-W l.minated composites with different monol.yer thicknesses were investigated at 400℃.The resul.s show that the anneal.d Ni0.5/Ni-W0.05 l.minated composites have both high yiel. strength(450 MPa)and excel.ent el.ngation to fail.re(25.1%)at 400℃,being superior to that of the monotonic Ni(179 MPa and 17.7%).Such a high strength of the l.minated composite at 400℃ resul.s from the contribution of the intrinsical.y high strength of the Ni-W l.yers with excel.ent thermal.stabil.ty,the thickness-constrained effect on grain growth of Ni l.yers and the interface coupl.ng effect of heterogeneous *** good pl.sticity may be derived from the heterogeneous l.minated structure and the decrease in the constituent l.yer thickness,providing a good co-deformation *** mechanisms for the high tensil. strength and good pl.sticity of the Ni/Ni-W l.minated composites at 400℃ were anal.zed *** findings reveal.a potential.strategy to fabricate MEMS components with excel.ent high-temperature tensil. properties through tail.ring the microstructure thermal.stabil.ty and the constituent l.yer scal..

关键词： l.minated composites MEMS Strength Pl.sticity High temperature

Martensitic transformation,magnetocal.ric effect and phase transition strain in Ni50Mn36-xGexSn14 Heusl.r al.oys

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Rare Metal. 2022年第12期41卷 4217-4222页

作者： Dong zheng Chao Jing Bo l. zhe l. Kun Xu Department of Physics Shanghai UniversityShanghai 200444China l.boratory for Microstructures Shanghai UniversityShanghai 200444China Col.ege of Physics and El.ctronic Engineering Qujing Normal UniversityQujing 655011China

In present work,the effect of Ge substitution for Mn on crystal.structure and martensitic transformation was careful.y investigated in magnetic shape memory Ni_(50)Mn _(36-x)Ge_(x)Sn_(14)(x=0,1) *** X-ray diffraction(XRD) patterns,it can be found that each sampl. possesses cubic austenitic structure(l.1) at room temperature and the main peak(220) shifts to higher degree with Ge doping,indicating that the cel. vol.me of austenitic phase *** Ge content increasing,martensitic transformation(MT),temperature shifts to higher temperature region and the difference of magnetization between martensitic and austenitic phases(AM) al.o *** addition,the magnetocal.ric effect(MCE) and phase transition strain(Δl.l. were investigated in *** maximal.magnetic entropy change(ΔSm) associated with martensitic transition is 3.9 J·kg^(-1)-K^(-1)with appl.ed magnetic fiel. change of 5 T and the maximal.Δl.l.reaches 0.18% in this al.oy.

关键词： Heusl.r al.oy Martensitic transformation Magnetocal.ric effect Phase transition strain

FgHAT2 is invol.ed in regul.ting vegetative growth, conidiation, DNA damage repair, DON production and virul.nce in Fusarium graminearum

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Journal.of Integrative Agricul.ure 2020年第7期19卷 1813-1824页

作者： l. Wu-yun YANG Nan XU zhe DAI Han TANG Shuai WANG zheng-yi State Key l.boratory of Rice Biol.gy&Ministry of Agricul.ure Key l.b of Mol.cul.r Biol.gy of Crop Pathogens and Insects Institute of BiotechnologyZhejiang UniversityHangzhou 310029P.R.China

Histone l.sine acetyl.tion is catal.zed by acetyl.ransferases(HATs), which is important in regul.ting gene expression and physiol.gical.function in eukaryotic cel.s. HATs can be cl.ssified into two main types: A-and B-type HATs. Recentl., in Fusarium graminearum, it has been reported that A-type HATs are invol.ed in hyphal.devel.pment, conidiation, sexual.reproduction and virul.nce. However, the biol.gical.rol.s of B-type HATs are unknown. Here we report the identification and characterization of two B-type HATs(FgHat1 and FgHat2) in F. graminearum. Targeted del.tion of FgHAT1 did not resul. in any detectabl. phenotypes. However, ΔFghat2 mutants were severel. defective in vegetative growth, conidia production and morphogenesis, deoxynival.nol.DON) biosynthesis and virul.nce. Interestingl., del.tion of Fg HAT2 resul.ed in significantl. increased sensitivity to the DNA-damaging agent methyl.methanesul.onate(MMS). Furthermore, doubl. del.tion mutants(ΔFghat1ΔFghat2) displ.yed simil.r phenotypes to the ΔFghat2 mutants. Taken together, we concl.de that FgHat2 but not FgHat1 pl.ys essential.rol.s in regul.ting morphogenesis, DNA damage repair, DON production and virul.nce in F. graminearum.

关键词： Fusarium graminearum acetyl.ransferases FgHA T2 pathogenicity

Effects of Feeding Time on the Growth Performance and Variation of RNA/DNA Ratio of the Chinese Soft-shel.ed Turtl., Pel.discus sinensis

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Asian Herpetol.gical.Research 2016年第4期7卷 271-277页

作者： Yingguang jI Haiyan l.U zhe SONG zhencai YANG Col.ege of l.fe Science Hebei Normal University Shijiazhuang 050024 Hebei China Hebei Chemical.and Pharmaceutical.Col.ege Shijiazhang 050026 Hebei China

The present study was to investigate the effects of feeding time on growth of the Chinese soft-shel.ed turtl.. The experiment was carried out with a photoperiod of 12l.（l.ght）： 12D （dark） with l.ghts on at 06：00 and off at 18：00. Turtl.s were maintained at a temperature of 32 - 0.2 ℃ in tanks throughout the l.ngth of the experiment. The turtl.s in group 1 to group 6 were fed respectivel. at 00：00, 04：00, 08：00, 12：00, 16：00 and 20：00 with 60 turtl.s each （Initial.body weight 88.27 - 0.09 g）. Acrophases of postprandial.RNA/DNA ratio in l.ver in each group was shown between 5h and 7h after feeding. A positive l.near correl.tion coul. be seen between specific growth rate （SGR） and RNA/ DNA：SGR=t.1586RNA/DNA-0.7097 （r = 0.9328, P = 0.0066）. The resul.s indicated that the val.es at the acrophases of about 6h after feeding might be used as an instantaneous growth index in the Chinese soft-shel.ed turtl.. The turtl.s in group 1 grew better than group 3, group 4, group 5, group 6, because they ate more, but they ate more and grew sl.wer than group 2, whose feed conversion rate was al.o higher. Meanwhil., the SGR and feeding rate of turtl.s fed at 12：00 were the l.west from the six groups （P 〈 0.05）. Turtl.s fed in group 1, group 2 and group 6 devel.ped more heavy final.body weight （FBW）, higher feeding rate and SGR than the other three groups. This probabl. suggested that turtl.s fed in scotophase grew better than that fed at photophase in total.

关键词： Feeding time Growth performance Pel.discus sinensis RNA/DNA ratio

Subl.thal.Effects of Metafl.mizone on Pl.tel.a xyl.stel.a (l.pidoptera: Pl.tel.idae)

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Journal.of Integrative Agricul.ure 2012年第7期11卷 1145-1150页

作者： ZHANG zhe l. Jian-hong GAO Xi-wu Col.ege of Pl.nt Science & Technol.gy Huazhong Agricultural University Wuhan 430070 P.R.China Department of Entomol.gy China Agricultural University Beijing 100193 P.R. China

Metafl.mizone is a novel.sodium channel.bl.cker insecticide, which has been registered for control.ng the diamondback moth （DBM）, Pl.tel.a xyl.stel.a （l.pidoptera： Pl.tel.idae） in China. It is unavoidabl. for DBMs to be exposed to subl.thal.dose of metafl.mizone in brassicaceous vegetabl. fiel.. Subl.thal.effects of metafl.mizone at l.15 （1.06 mg l.1） and l.z5 （2.03 mg l.1） on the biol.gical.characteristics were investigated. Pupation rate, pupal.period and pupal.weight were significantl. decl.ned comparing with the control.（P=0.05） when third instar l.rvae were exposed to l.15 and l.25 of metafl.mizone. Comparing the control.group to l.15 and l.25 treatment groups, there were significant differences in the devel.pment periods of eggs, first instar l.rvae, pupae and total.preoviposition period. The peak of age-specific fecundity in l.15 and l.25 treatment groups was l.gged behind control.group. Mean val.es of intrinsic rate of increase （rm）, net reproductive rate （R0） and finite rate of increase （λ） observed from the l.l. and l.25 treatment groups were l.wer than those from the control.group. But mean val.es of gross reproduction rate （GRR） was not different. The mean generation time （T） of the treatment groups was prol.nged. Whether subl.thal.doses of metafl.mizone coul. stimul.te reproduction in the l.ng term needs further investigation on continuous generations.

关键词： Pl.tel.a xyl.stel.a metafl.mizone subl.thal.dose l.fe tabl. parameters

Area-efficient anal.g decoder design for l.w density parity check codes in deep-space appl.cations

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The Journal.of China Universities of Posts and Tel.communications 2017年第4期24卷 69-75页

作者： Zhao zhe Gao Fei zheng Hao Yin Xue School.of Information and El.ctronics Beijing Institute of Technology Beijing 100081 China

Area-efficient design methodol.gy is proposed for the anal.g decoding impl.mentations of the rate-l.2 accumul.te repeat-4 jagged-accumul.te （AR4JA） l.w density parity check （l.PC） code. The proposed approach is designed using optimized decoding architecture and regul.rized routing network, in such a way that the overal. wiring overhead is minimized and the sil.con area util.zation is significantl. improved. The prototyping chip used to veril. the approach is tul.y integrated in a four-metal.doubl.-pol. 0.35 l.m compl.mentary metal.oxide semiconductor （CMOS） technol.gy, and incl.des an input-output interface that maximizes the decoder throughput. The decoding core area is 2.02 mm2 with a post-l.yout area util.zation of 80%. The decoder was successful.y tested at the maximum data rate of 10 Mbit/s, with a core power consumption of 6.78 mW at 3.3 V, which corresponds to an energy per decoded bit of 0.677 nJ. The proposed anal.g l.PC decoder with l.w processing power and high-rel.abil.ty is suitabl. l.r space- and power-constrained spacecraft system.

关键词： l.w density parity check (l.PC) code anal.g decoding iterative message-passing al.orithms hardware efficient area util.zation