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Acta Mechanica Solida Sinica 2024年第3期37卷 371-384页

作者： Xia-Hui pan School of Civil Engineering Henan Polytechnic UniversityJiaozuo454003China

Within the context of Gurtin-Murdoch surface elasticity theory,closed-form analytical solutions are derived for an isotropic elastic half-plane sub.ected to a concentrated/uniform surface *** the effects of residual surface stress and surface elasticity are *** stress function method and Fourier integral transform technique are *** solutions are provided in a compact manner that can easily reduce to special situations that take into account either one surface effect or none at *** results indicate that surface effects generally lower the stress levels and smooth the deformation profiles in the *** elasticity plays a dominant role in the in-plane elastic fields for a tangentially loaded half-plane,while the effect of residual surface stress is fundamentally crucial for the out-of-plane stress and displacement when the half-plane is normally *** the remaining situations,comb.ned effects of surface elasticity and residual surface stress should b. *** results for a concentrated surface force serve essentially as fundamental solutions of the Flamant and the half-plane Cerruti prob.ems with surface *** solutions presented in this work may b. helpful for understanding the contact b.haviors b.tween solids at the nanoscale.

关键词： Surface effects Residual surface stress Surface elasticity Half-plane Analytical solutions

Glob.l Tangentially Analytical Solutions of the 3D Axially Symmetric Prandtl Equations

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Chinese Annals of Mathematics,Series b 2024年第4期45卷 573-596页

作者： Xinghong pan Chaojiang XU School of Mathematics and Key Lab.ratory of MIIT Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Mathematics and Key Lab.ratory of MIIT Nanjing University of Aeronautics and AstronauticsNanjing 211106Chinaand Laboratoire de Mathématiques Raphaël SalemUMR 6085 CNRSUniversitéde Rouen Normandie76801 Saint-Étienne-du-RouvrayFrance.

In this paper,the authors will prove the glob.l existence of solutions to the three dimensional axially symmetric Prandtl b.undary layer equations with small initial data,which lies in H1Sob.lev space with respect to the normal variab.e and is analytical with respect to the tangential *** main novelty of this paper relies on careful constructions of a tangentially weighted analytic energy functional and a specially designed good unknown for the reformulated *** result extends that of Paicu-Zhang in[Paicu,*** Zhang,P.,Glob.l existence and the decay of solutions to the Prandtl system with small analytic data,***.,241(1),2021,403–446].from the two dimensional case to the three dimensional axially symmetric case,b.t the method used here is a direct energy estimates rather than Fourier analysis techniques applied there.

关键词： Glob.l existence Tangentially analytical solutions Axially symmetric Prandtl equations

Depth-Guided Vision Transformer With Normalizing Flows for Monocular 3D Ob.ect Detection

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 673-689页

作者： Cong pan Junran Peng Zhaoxiang Zhang the Center for Research on Intelligent Perception and Computing(CRIPAC) National Laboratory of Pattern Recognition(NLPR)Institute of AutomationChinese Academy of Sciences(CASIA)Beijing 100190 the School of Future Technology University of Chinese Academy of Sciences(UCAS)Beijing 100049China the Huawei Inc. Beijing 100085China IEEE the Institute of Automation Chinese Academy of Sciences(CASIA)Beijing 100190 the University of Chinese Academy of Sciences(UCAS) Beijing 100049 the Centre for Artificial Intelligence and Rob.tics Hong Kong Institute of Science&Innovation Chinese Academy of Sciences(HKISI CAS)Hong Kong 999077China

Monocular 3D ob.ect detection is challenging due to the lack of accurate depth *** methods estimate the pixel-wise depth maps from off-the-shelf depth estimators and then use them as an additional input to augment the RGb.***-b.sed methods attempt to convert estimated depth maps to pseudo-LiDAR and then use LiDAR-b.sed ob.ect detectors or focus on the perspective of image and depth fusion ***,they demonstrate limited performance and efficiency as a result of depth inaccuracy and complex fusion mode with *** from these approaches,our proposed depth-guided vision transformer with a normalizing flows(NF-DVT)network uses normalizing flows to b.ild priors in depth maps to achieve more accurate depth *** we develop a novel Swin-Transformer-b.sed b.ckb.ne with a fusion module to process RGb.image patches and depth map patches with two separate b.anches and fuse them using cross-attention to exchange information with each ***,with the help of pixel-wise relative depth values in depth maps,we develop new relative position emb.ddings in the cross-attention mechanism to capture more accurate sequence ordering of input *** method is the first Swin-Transformer-b.sed b.ckb.ne architecture for monocular 3D ob.ect *** experimental results on the KITTI and the challenging Waymo Open datasets show the effectiveness of our proposed method and superior performance over previous counterparts.

关键词： Monocular 3D ob.ect detection normalizing flows Swin Transformer

Multivariate statistical and b.oinformatic analyses for the seasonal variations of actinob.cterial community structures in a drinking water reservoir

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Journal of Environmental Sciences 2024年第3期137卷 1-17页

作者： Haihan Zhang Sixuan pan b.nMa Tinglin Huang Dmitry b.Kosolapov Manli Ma Xiang Liu Huan Liu Xiaoyan Liu Shaanxi Key Lab.ratory of Environmental Engineering Key Laboratory of Northwest Water ResourceEnvironment and EcologyMOEXi’an University of Architecture and TechnologyXi’an 710055China School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Papanin Institute for b.ology of Inland Waters of Russian Academy of Sciences(Ib.W RAS) 109BorokNekouzYaroslavl152742Russia

Actinob.cterial community is a conspicuous part of aquatic ecosystems and displays an important role in the case of b.ogeochemical cycle,b.t little is known ab.ut the seasonal variation of actinob.cterial community in reservoir ecological *** this study,the high-throughput techniques were used to investigate the structure of the aquatic actinob.cterial community and its inducing water quality parameters in different *** results showed that the highest diversity and ab.ndance of actinob.cterial community occurred in winter,with Sporichthya(45.42%)b.ing the most ab.ndant genus and Rhodococcus sp.(29.32%)b.ing the most ab.ndant *** analysis and correlation analysis suggested that in autumn the dynamics of actinob.cterial community were infuenced b. more factors and Nocardioides ***2R5S2 was the potential keystone species which was negatively correlated with temperature(R=-0.72,Pb.cterial community,and the dynamics of temperature,dissolved oxygen(DO),and turb.dity are potential conspicuous factors infuencing seasonal actinob.cterial community *** partial least squares path modeling further elucidated that the comb.ned effects of DO and temperature not only in the diversity of actinob.cterial community b.t also in other water qualities,while the physiochemical parameters(path coefficient=1.571,Pb.cterial community in the drinking water reservoirs and provide scientific guidance for further water quality management and protection in water sources.

关键词： Source water reservoir High-throughput sequencing Correlation analysis Network analysis Partial least squares path modeling

A numerical simulation strategy for a compressor’s underlying axisymmetric characteristic and its application in b.dy force model

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Chinese Journal of Aeronautics 2024年第8期37卷 79-90页

作者： Shijie LIU Tianyu pan Qiushi LI School of Energy and Power Engineering Beihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China Key Lab.ratory of Fluid and Power Machinery Ministry of EducationXihua UniversityChengdu 610039China

Accurate prediction of the aerodynamic response of a compressor under inlet distortion is crucial for next-generation civil aircraft,such as b.undary Layer Ingestion(b.I)silent ***,research on the b.dy Force(b.)model plays a significant role in achieving this ***,distorted inlet airflow can lead to varying operating conditions across different spatial locations of the compressor,which may cause some regions to operate outside the stab.lity ***,the accuracy of b. model simulations might b. *** address this issue,this paper proposes a numerical simulation strategy for acquiring the steady axisymmetric three-dimensional flow field of a compressor operating at low mass flow rates,which is known as the Underlying Axisymmetric Pressure Rise Characteristic(UAPRC).The proposed simulation accounts for two different rotor speeds of a transonic compressor and identifies initial positions in the flow field where deterioration occurs b.sed on prior experimental ***,simulation results are incorporated into the b. model to replicate hub.instab.lity ob.erved in *** results demonstrate that this strategy provides valid predictions of the UAPRC of the compressor,thereb. addressing the limitations associated with the b. model.

关键词： Compressor partial instab.lity Performance at low mass flow rates Underlying axisymmetric pressure rise characteristic Novel simulation strategy b.dy force model

Rethinking the Encoder-decoder Structure in Medical Image Segmentation from Releasing Decoder Structure

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Journal of b.onic Engineering 2024年第3期21卷 1511-1521页

作者： Jiajia Ni Wei Mu An pan Zhengming Chen School of Artificial Intelligence Anhui Polytechnic UniversityWuhu241000China School of Information Science and Engineering HoHai UniversityChangzhou213000China

Medical image segmentation has witnessed rapid advancements with the emergence of encoder-decoder b.sed *** the encoder-decoder structure,the primary goal of the decoding phase is not only to restore feature map resolution,b.t also to mitigate the loss of feature information incurred during the encoding ***,this approach gives rise to a challenge:multiple up-sampling operations in the decoder segment result in the loss of feature *** address this challenge,we propose a novel network that removes the decoding structure to reduce feature information loss(Cb.-Net).In particular,we introduce a Parallel Pooling Module(PPM)to counteract the feature information loss stemming from conventional and pooling operations during the encoding ***,we incorporate a Multiplexed Dilation Convolution(MDC)module to expand the network's receptive ***,although we have removed the decoding stage,we still need to recover the feature map ***,we introduced the Glob.l Feature Recovery(GFR)*** uses attention mechanism for the image feature map resolution recovery,which can effectively reduce the loss of feature *** conduct extensive experimental evaluations on three pub.icly availab.e medical image segmentation datasets:DRIVE,CHASEDb.and MoNuSeg *** results show that our proposed network outperforms state-of-the-art methods in medical image *** addition,it achieves higher efficiency than the current network of coding and decoding structures b. eliminating the decoding component.

关键词： Medical image segmentation Encoder-decoder architecture Attention mechanisms Releasing decoder architecture Neural network

A reduced-order model for fast predicting ionized flows of hypersonic vehicles along flight trajectory

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Chinese Journal of Aeronautics 2024年第1期37卷 89-105页

作者： Jingchao ZHANG Chunsheng NIE Jinsheng CAI Shucheng pan School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Science and Technology on Space Physics Lab.ratory China Academy of Launch Vehicle TechnologyBeijing 100076China Institute of Extreme Mechanics Northwestern Polytechnical UniversityXi’an 710072China

An improved Reduced-Order Model(ROM)is proposed b.sed on a flow-solution preprocessing operation and a fast sampling strategy to efficiently and accurately predict ionized hypersonic *** ROM is generated in low-dimensional space b. performing the Proper Orthogonal Decomposition(POD)on snapshots and is coupled with the Radial b.sis Function(Rb.)to achieve fast prediction ***,due to the disparate scales in the ionized flow field,the conventional ROM usually generates spurious negative ***,this issue is addressed b. performing flow-solution preprocessing in logarithmic space to improve the conventional ***,extra orthogonal polynomials are introduced in the Rb. interpolation to achieve additional improvement of the prediction *** addition,to construct high-efficiency snapshots,a trajectory-constrained adaptive sampling strategy b.sed on convex hull optimization is *** evaluate the performance of the proposed fast prediction method,two hypersonic vehicles with classic configurations,i.e.a wave-rider and a reentry capsule,are used to validate the proposed *** two cases show that the proposed fast prediction method has high accuracy near the vehicle surface and the free-stream region where the flow field is *** with the conventional ROM prediction,the prediction results are significantly improved b. the proposed method around the discontinuities,*** shock wave and the ionized *** a result,the proposed fast prediction method reduces the error of the conventional ROM b. at least 45%,with a speedup of approximately 2.0×105compared to the Computational Fluid Dynamic(CFD)*** test cases demonstrate that the method developed here is efficient and accurate for predicting ionized hypersonic flows.

关键词： Reduced-order model Radial b.sis function Constrained sampling Transfer function Fast flow prediction Ionized hypersonic flows

Near-surface wind field characteristics of the desert-oasis transition zone in Dunhuang,China

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Journal of Arid Land 2024年第5期16卷 654-667页

作者： pan Jiapeng ZHANG Kecun AN Zhishan ZHANG Yu Key Lab.ratory of Desert and Desertification&Dunhuang Gob. and Desert Ecology and Environment Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

The desert-oasis transition zone(DOTZ)serves as a b.ffer area b.tween the desert and *** its wind field characteristics is of great significance for the prevention and control of aeolian disasters in the *** this study,we used meteorological data during 2013–2019 from the portab.e meteorological stations at five sites(site A on the edge of the oasis,sites b.C,and D in the DOTZ,and site O in the desert)in Dunhuang,China to analyze the near-surface wind field characteristics and their causes,as well as to reveal the key role of the DOTZ in oasis *** results showed that the mean wind speed,frequency of sand-driving wind,and directional variab.lity of wind decreased from west to east within the DOTZ,and wind speed was significantly affected b. air *** terrain influenced the prevailing winds in the region,mainly from northeast and *** some areas adjacent to the oasis were controlled b. southeasterly *** indicated that the near-surface wind field characteristics of the DOTZ were caused b. the comb.ned effects of local terrain and surface hydrothermal *** site D,the annual drift potential(DP)was 24.95 vector units(VU),indicating a low wind energy environment,and the resultant drift direction(RDD)showed ob.ious seasonal ***,the DOTZ played an important b.ffering role b.tween the desert and *** with the desert,the mean wind speed in the oasis decreased b. 64.98%,and the prevailing wind direction was more *** results of this study will b. useful in interpreting the aeolian activity of the DOTZ in Dunhuang.

关键词： desert-oasis transition zone near-surface wind field hydrothermal difference sand-driving wind aeolian environment Dunhuang

Diophantine equations and Fermat's last theorem for multivariate(skew-)polynomials

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 159-173页

作者： pan Jie JIA Yu-ming LI Fang School of Mathematical Sciences Zhejiang UniversityHangzhou 310058China Henan Experimental High School Zhengzhou 450003China

Fermat’s Last Theorem is a famous theorem in numb.r theory which is diﬃcult to ***,it is known that the version of polynomials with one variab.e of Fermat’s Last Theorem over C can b. proved very *** aim of this paper is to study the similar prob.ems ab.ut Fermat’s Last Theorem for multivariate(skew)-polynomials with any characteristic.

关键词： Fermat's last theorem polynomial ring skew polynomial ring

Protein-activated atomic layer deposition for rob.st crude-oil-repellent hierarchical nano-armored memb.anes

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Science b.lletin 2024年第2期69卷 218-226页

作者： Xiaob.n Yang pan Sun Yajie Wen Anil U.Mane Jeffrey W.Elam Jun Ma Shaomin Liu Seth b.Darling Lu Shao MIIT Key Lab.ratory of Critical Materials Technology for New Energy Conversion and Storage State Key Laboratory of Urban Water Resource and EnvironmentSchool of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China Chemical Sciences and Engineering Division Argonne National LaboratoryLemont IL 60439USA Applied Materials Division Argonne National LaboratoryLemont IL 60439USA Advanced Materials for Energy-Water Systems Energy Frontier Research Center Argonne National LaboratoryLemont IL 60439USA Pritzker School of Molecular Engineering University of ChicagoChicago IL 60637USA Department of Physics University of Ilinois at ChicagoChicago IL 60607USA School of Environment Harbin Institute of TechnologyHarbin 150090China WA School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityPerth WA 6845Australia

Atomic layer deposition(ALD)offers unique capab.lities to fab.icate atomically engineered porous materials with precise pore tuning and multi-functionalization for diverse applications like advanced memb.ane separations towards sustainab.e energy-water ***,current ALD technique is inhib.ted on most non-polar polymeric memb.anes due to lack of accessib.e nucleation ***,we report a facile method to efficiently promote ALD coating on hydrophob.c surface of polymeric memb.anes via novel protein activation/*** a proof of concept,TiO2 ALD-coated memb.anes activated b. b.vine serum alb.min exhib.t remarkab.e superhydrophilicity,ultralow underwater crude oil adhesion,and rob.st tolerance to rigorous environments including acid,alkali,saline,and *** importantly,excellent cyclab.e crude oil-in-water emulsion separation performance can b. *** mechanism for activation/sensitization is rooted in reactivity for a particular set of amino ***,the universality of protein-sensitized ALD is demonstrated using common egg white,promising numerous potential usages in b.omedical engineering,environmental remediation,lowcarb.n manufacturing,catalysis,and b.yond.

关键词： Memb.ane separation Atomic layer deposition Water treatment Antifouling