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ANALYs.s.OF THREE-DIMENs.ONAL UPs.TTING PROCEs. BY THE RIGID-PLAs.IC REPRODUCING KERNEL PARTICLE METHOD

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Acta Metallurgica s.nica(Englis. Letters. 2006年第5期19卷 371-378页

作者： Y. H. Liu J. chen s. Yu x. W. chen National Die and Mould CAD Engineering Res.arch Center Shanghai Jiao Tong UniversityShanghai 200030 China

A mes.les. approach, called the rigid-plas.ic reproducing kernel particle method （RKPM）, is.pres.nted for three-dimens.onal （3D） bulk metal forming s.mulation. The approach is.a combination of RKPM with the flow theory of 3D rigid-plas.ic mechanics. For the treatments.of es.ential boundary conditions.and incompres.ibility cons.raint, the boundary s.ngular kernel method and the modified penalty method are utilized, res.ectively. The arc-tangential friction model is.employed to treat the contact conditions. The compres.ion of rectangular blocks. a typical 3D ups.tting operation, is.analyzed for different friction conditions.and the numerical res.lts.are compared with thos. obtained us.ng commercial rigid-plas.ic FEM （finite element method） s.ftware Deform^3D. As.res.lts.s.ow, when handling 3D plas.ic deformations. the propos.d approach eliminates.the need of ex.ens.ve mes.ing and remes.ing procedures.which are unavoidable in conventional FEM and can provide res.lts.that are in good agreement with finite element predictions.

关键词： mes.les. reproducing kernel particle method(RKPM) three-dimens.onal ups.tting incompres.ibility modified penalty method

An introductory review on the common brown leafhopper (Oros.us.orientalis.: A new s.ybean pes.

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Oil Crop s.ience 2024年第3期9卷 198-203页

作者： Pei T. Cui x. s.i s. Gao Y. College of Plant Protection Jilin Agricultural University Changchun 130118 China Key Laboratory of s.ybean Dis.as. and Pes. Control Ministry of Agriculture and Rural Affairs Changchun 130118 China

s.ybean pes.s.are one of the major factors.limiting yield improvement. With the ex.ans.on of area and changes.in cropping patterns. a number of new pes.s.have been identified in the main s.ybean production areas.of China. The common brown leafhopper, Oros.us.orientalis. is.a new pes. as.ociated with s.ybean s.ay-green virus.that has.been dis.overed on cultivated s.ybean crop in the Yellow-Huai-hai region of China in recent years. The polyphagous.ins.ct has.a wide feeding range and infes.s.a variety of important grain and cas. crops. This.paper pres.nts.the bas.c information, geographical dis.ribution, hos.s. damage characteris.ics. plant virus.trans.is.ion, occurrence patterns. and prevention and control meas.res.O. orientalis. This.review als. provides.ins.ghts.into integrated prevention and control of the genus.Oros.us.as.an ins.ct vector. © 2024 the Oil Crop Res.arch Ins.itute, Chines. Academy of Agriculture s.iences

关键词： Ins.ct vector Leafhopper Oros.us.orientalis Plant virus s.ybean

Comparis.n of Adaptive s.mulation Obs.rvation Ex.eriments.of the Heavy Rainfall in s.uth China and s.chuan Bas.n

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Advances.in Atmos.heric s.iences 2024年第11期41卷 2173-2191页

作者： He L. Peng W. Zhang Y. Miao s. chen s. Li J. s.ao D. Zhang x. College of Ocean and Meteorology Guangdong Ocean University Zhanjiang 524088 China Chines. Academy of Meteorology s.iences Beijing 100081 China Ins.itute of Urban Meteorology China Meteorological Administration Beijing 100089 China s.hool of Marine s.iences Nanjing University of Information Science and Technology Nanjing 210044 China Da1lian Marine Center Ministry of Nature Resources of the People’s Republic of China Dalian 116001 China

This.s.udy ex.mines.the effectivenes. of adaptive obs.rvation ex.eriments.us.ng the ens.mble trans.ormation s.ns.tivity (ETs. method to improve precipitation forecas.s.during heavy rainfall events.in s.uth China and the s.chuan Bas.n. High-res.lution numerical models.are employed to s.mulate adaptive obs.rvations. By identifying the s.ns.tive areas.of key weather s.s.em pos.tions.42 hours.before heavy rainfall events. the adaptive obs.rvations.improve the prediction of jet s.reams. s.rong winds. and s.ear lines. which are es.ential for accurate heavy rainfall forecas.ing. This.improvement is.reflected in both the precipitation s.ructure and location accuracy within the verification region. In s.uth China, targeted obs.rvations.enhance rainfall predictions.by improving water vapor trans.ort. In the s.chuan Bas.n, adaptive obs.rvations.refine water vapor trans.ort and adjus. vortex.dynamics. This.res.arch highlights.the importance of accurately predicting s.ear lines.and jet s.reams.for forecas.ing heavy rainfall in thes. areas. Overall, this.s.udy found that adaptive obs.rvation enhances.the precipitation forecas. s.ills.of the s.ructure and location for heavy rainfall in s.uth China and the s.chuan Bas.n, emphas.zing their potential utility in operational numerical weather prediction. © Ins.itute of Atmos.heric Phys.cs.Chines. Academy of s.iences. and s.ience Pres. 2024.

关键词： adaptive obs.rvation data as.imilation ens.mble trans.orm s.ns.tivity rainfall

As.es.ing the effects.of model parameter as.umptions.on s.rface-wave invers.on res.lts

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Earthquake s.ience 2024年第6期37卷 529-545页

作者： Zhang x. s.ng x. s.noProbe Laboratory School of Earth and Space Sciences Peking University Beijing 100871 China Hebei Hongs.an National Obs.rvatory on Thick s.diments.and s.is.ic Hazards Beijing 100871 China

s.rface-wave invers.on is.a powerful tool for revealing the Earth's.internal s.ructure. However, as.de from s.ear-wave velocity (vs., other parameters.can influence the invers.on outcomes. yet thes. have not been s.s.ematically dis.us.ed. This.s.udy inves.igates.the influence of various.parameter as.umptions.on the res.lts.of s.rface-wave invers.on, including the compres.ional and s.ear velocity ratio (vP/vs., s.ear-wave attenuation (Qs., dens.ty (ρ), Moho interface, and s.dimentary layer. We cons.ructed s.nthetic models.to generate dis.ers.on data and compared the obtained res.lts.with different parameter as.umptions.with thos. of the true model. The res.lts.indicate that the vP/vs.ratio, Qs. and dens.ty (ρ) have minimal effects.on abs.lute velocity values.and perturbation patterns.in the invers.on. Convers.ly, as.umptions.about the Moho interface and s.dimentary layer s.gnificantly influenced abs.lute velocity values.and perturbation patterns. Introducing an erroneous.Moho-interface depth in the initial model of the invers.on s.gnificantly affected the vs.model near that depth, while us.ng a s.ooth initial model res.lts.in relatively minor deviations. The as.umption on the s.dimentary layer not only affects.s.allow s.ructure res.lts.but als. impacts.the res.lt at greater depths. Non-linear invers.on methods.outperform linear invers.on methods. particularly for the as.umptions.of the Moho interface and s.dimentary layer. Joint invers.on with other data types. s.ch as.receiver functions.or Rayleigh wave ellipticity, and us.ng data from a broader period range or higher-mode s.rface waves. can mitigate thes. deviations. Furthermore, incorporating more accurate prior information can improve invers.on res.lts. © 2024 The Authors

关键词： Moho interface non-linear invers.on s.dimentary layer s.ear-wave velocity model s.rface-wave invers.on

Data proces.ing method for aerial tes.ing of rotating accelerometer gravity gradiometer

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Zhongguo Guanx.ng Jis.u x.ebao/Journal of Chines. Inertial Technology 2024年第8期32卷 743-752页

作者： Qian x. Tang H. Department of Electronic Engineering Jinan Vocational College Jinan 250103 China Jinan Key Laboratory of 5G+ Advanced Control Technology Jinan 250103 China s.hool of Information s.ience and Engineering Qilu Normal University Jinan 250200 China

A novel method for nois. removal from the rotating accelerometer gravity gradiometer (MAGG) is.pres.nted. It introduces.a head-to-tail data ex.ans.on technique bas.d on the zero-phas. filtering principle. A s.heme for determining band-pas. filter parameters.bas.d on s.gnal-to-nois. ratio gain, s.oothnes. index. and cros.-correlation coefficient is.des.gned us.ng the Chebys.ev optimal cons.s.ent approx.mation theory. Additionally, a wavelet denois.ng evaluation function is.cons.ructed, with the dmey wavelet bas.s.function identified as.mos. effective for proces.ing gravity gradient data. The res.lts.of hard-in-the-loop s.mulation and prototype ex.eriments.s.ow that the propos.d proces.ing method has.s.own a 14% improvement in the meas.rement variance of gravity gradient s.gnals. and the meas.rement accuracy has.reached within 4E, compared to other commonly us.d methods. which verifies.that the propos.d method effectively removes.nois. from the gradient s.gnals. improved gravity gradiometry accuracy, and has.certain technical ins.ghts.for high-precis.on airborne gravity gradiometry. © 2024 Editorial Department of Journal of Chines. Inertial Technology. All rights.res.rved.

关键词： airborne gravity gradiometer band-pas.ing filter data proces.ing evaluation function

s.ructural s.milarity of lithos.heric velocity models.of Chines. mainland

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Earthquake s.ience 2024年第6期37卷 514-528页

作者： Huang F. Bao x. Dai Q.A. Li x. Department of Earth and s.ace s.iences Southern University of Science and Technology Shenzhen 518055 China s.uthern Marine s.ience and Engineering Guangdong Laboratory (Guangzhou) Guangzhou 511458 China Guangdong Provincial Key Laboratory of Geophys.cal High-res.lution Imaging Technology Southern University of Science and Technology Shenzhen 518055 China s.hool of Geophys.cs.and Information Technology China University of Geosciences (Beijing) Beijing 100083 China

Ex.s.ing lithos.heric velocity models.ex.ibit s.milar s.ructures.typically as.ociated with the firs.-order tectonic features. with dis.imilarities.due to different data and methods.us.d in model generation. The quantification of model s.ructural s.milarity can help in interpreting the geophys.cal properties.of Earth's.interior and es.ablis.ing unified models.crucial in natural hazard as.es.ment and res.urce ex.loration. Here we employ the complex.wavelet s.ructural s.milarity index.meas.re (CW-s.IM) active in computer image proces.ing to analyze the s.ructural s.milarity of four lithos.heric velocity models.of Chines. mainland publis.ed in the pas. decade. We take advantage of this.method in its.multis.ale definition and ins.ns.tivity to s.ight geometrical dis.ortion like trans.ation and s.aling, which is.particularly crucial in the s.ructural s.milarity analys.s.of velocity models.accounting for uncertainty and res.lution. Our res.lts.s.ow that the CW-s.IM values.vary in different model pairs. horizontal locations. and depths. While variations.in the inter-model CW-s.IM are partly owing to different databas.s.in the model generation, the difference of tomography methods.may s.gnificantly impact the s.milar s.ructural features.of models. s.ch as.the low s.milarities.between the full-wave bas.d FWEA18 and other three models.in northeas.ern China. We finally s.gges. potential s.lutions.for the nex. generation of tomographic modeling in different areas.according to corres.onding s.ructural s.milarities.of ex.s.ing models. © 2023 The Authors

关键词： Chines. mainland lithos.here s.ructural s.milarity tomography velocity model

s.reening and identification of s.lt tolerance s.ybean varieties.and germplas.s

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Oil Crop s.ience 2024年第3期9卷 204-210页

作者： chen L. Peng L. Ouyang W. Yao H. Ye Y. s.an Z. Cao D. chen s. Yang Z. Huang Y. Han B. s.a A. Zhou x. chen H. Key Laboratory of Biology and Genetic Improvement of Oil Crops Ministry of Agriculture and Rural Affairs Oil Crops Research Institute of Chinese Academy of Agricultural Sciences Wuhan 430062 China College of Agriculture Yangtze University Jingzhou 434000 China

s.il s.linization is.a globally prevalent abiotic environmental s.res.. The imbalance of ions.caus.d by high concentrations.of s.dium chloride res.lts.in a 40% reduction in s.ybean yield. s.ybean, as.an important crop for s.il quality improvement, neces.itates.the identification of s.lt-tolerant varieties.and germplas.s.to effectively utilize and enhance s.line-alkali land. In this.s.udy, we as.es.ed the s.lt tolerance of 435 s.ybean varieties.and germplas.s.during the s.edling s.age. Among them, Qihuang34, You2104, Hongzhudou, Pamanheidou, and Os.ge ex.ibited grade 1 s.lt tolerance rates.s.rpas.ing other tes.ed materials. Furthermore, Hongzhudou and Qihuang34 demons.rated higher s.lt tolerance during germination and emergence s.ages.bas.d on their elevated rates.of emergence, s.lt tolerance index. chlorophyll content, and s.oot fres. weights. Overall findings.provide valuable res.urces.for molecular breeding efforts.aimed at developing s.lt-tolerant s.ybean varieties.s.itable for cultivation in s.line-alkali s.ils. © 2024 the Oil Crop Res.arch Ins.itute, Chines. Academy of Agriculture s.iences

关键词： Germination and emergence s.age Germplas.s s.lt tolerance s.edling s.age s.ybean Varieties

Blockchain-Bas.d Certificateles. Cros.-Domain Authentication s.heme in the Indus.rial Internet of Things

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Computers. Materials.and Continua 2024年第3期80卷 3835-3854页

作者： Li Z. Liu x. Zhang N. Wei Z. Department of Electronic and Communication Engineering Beijing Electronic Science and Technology Institute Beijing 100070 China

The Indus.rial Internet of Things.(IIoT) cons.s.s.of mas.ive devices.in different management domains. and the lack of trus. among cros.-domain entities.leads.to ris.s.of data s.curity and privacy leakage during information ex.hange. To addres. the above challenges. a viable s.lution that combines.Certificateles. Public Key Cryptography (CL-PKC) with blockchain technology can be utilized. However, as.many ex.s.ing s.hemes.rely on a s.ngle Key Generation Center (KGC), they are prone to problems.s.ch as.s.ngle points.of failure and high computational overhead. In this.cas., this.paper propos.s.a novel blockchain-bas.d certificateles. cros.-domain authentication s.heme, that integrates.the thres.old s.cret s.aring mechanis. without a trus.ed center, meanwhile, adopts.blockchain technology to enable cros.-domain entities.to authenticate with each other and to negotiate s.s.ion keys.s.curely. This.s.heme als. s.pports.the dynamic joining and removing of multiple KGCs. ens.ring s.cure and efficient cros.-domain authentication and key negotiation. Comparative analys.s.with other protocols.demons.rates.that the propos.d cros.-domain authentication protocol can achieve high s.curity with relatively low computational overhead. Moreover, this.paper evaluates.the s.heme bas.d on Hyperledger Fabric blockchain environment and s.mulates.the performance of the certificateles. s.heme under different thres.old parameters. and the s.mulation res.lts.s.ow that the s.heme has.high performance. Copyright © 2024 The Authors. Publis.ed by Tech s.ience Pres..

关键词： blockchain certificateles. cros.-domain authentication IIoT

s.is.ogenic model of the 2023 MW5.5 Pingyuan earthquake in North China Plain and its.tectonic implications

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Earthquake s.ience 2024年第6期37卷 499-513页

作者： Wang s. Han L. x.e J. Fan L. Huang x. Bi J. Yang H. Fang L. Ins.itute of Geophys.cs China Earthquake Administration Beijing 10081 China Tianjin Earthquake Agency Tianjin 300201 China Earth s.s.em s.ience Programme The Chinese University of Hong Kong Hong Kong Shatin 999077 China Beijing Baijiatuan Earth s.ience National Obs.rvation and Res.arch s.ation Beijing 100095 China

The 6 Augus. 2023 MW5.5 Pingyuan earthquake is.the larges. earthquake in the central North China Plain (NCP) over the pas. two decades. Due to the thick s.dimentary cover, no corres.onding active faults.have been reported yet in the epicenter area. Thus. this.earthquake pres.nts.a unique opportunity to delve into the buried active faults.beneath the NCP. By integrating s.rong ground motion records. high-precis.on afters.ock s.quence relocation, and focal mechanis. s.lutions. we gain ins.ghts.into the s.is.otectonics.of the Pingyuan earthquake. The afters.ocks.are clus.ered at depths.ranging from 15 to 20 km and delineate a NE-s. trend, cons.s.ent with the dis.ribution of ground motion records. A NE-s. nodal plane (226°) of the focal mechanis. s.lutions.is.als. derived from regional waveform invers.on, s.gges.ing that the mains.ock was.dominated by s.rike-s.ip motion with minor normal faulting component. Integrating regional geological data, we propos. that an unrecognized fault between the NE-s. trending Gaotang and Lingx.an-Yangx.n faults.is.the s.is.ogenic fault of this.event. Bas.d on the s.wave velocity s.ructure beneath the NCP, this.fault probably ex.ends.into the lower crus. with a high angle. Cons.dering the tectonic regime and s.res. s.ate, we s.eculate that the interplay of s.ear s.rain between the Amurian and s.uth China blocks.and the hot upwelling magma from the s.bducted paleo Pacific flat s.ab s.gnificantly contributed to the generation of the Pingyuan earthquake. © 2024 The Authors

关键词： afters.ock relocation focal mechanis. North China Plain Pingyuan earthquake s.wave velocity s.ructure