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Generalized polynomial chaos expansion by reanalysis using static condensation based on substructuring

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Applied mathematics and mechanics(English Edition) 2024年第5期45卷 819-836页

作者： D.LEE S.chang j.LEE Department of Automotive Engineering Hanyang UniversitySeoul 04763Republic of Korea School of mechanical Engineering Chungnam National UniversityDaejeon 34134Republic of Korea Department of mechanical Robotics and Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea

This paper presents a new computational method for forward uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary and dependent random *** method consists of a generalized polynomial chaos expansion(GPCE)for statistical moment and reliability analyses associated with the stochastic output and a static reanalysis method to generate the input-output data *** the reanalysis,we employ substructuring for a structure to isolate its local regions that vary due to random *** allows for avoiding repeated computations of invariant substructures while generating the input-output data *** substructuring with static condensation further improves the computational efficiency of the reanalysis without losing ***,the GPCE with the static reanalysis method can achieve significant computational saving,thus mitigating the curse of dimensionality to some degree for UQ under high-dimensional *** numerical results obtained from a simple structure indicate that the proposed method for UQ produces accurate solutions more efficiently than the GPCE using full finite element analyses(FEAs).We also demonstrate the efficiency and scalability of the proposed method by executing UQ for a large-scale wing-box structure under ten-dimensional(all-dependent)random inputs.

关键词： forward uncertainty quantification(UQ) generalized polynomial chaos expansion(GPCE) static reanalysis method static condensation substructuring

连续超声评估乳腺癌各分子亚型的肿瘤体积倍增时间

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国际医学放射学杂志 2014年第6期 598-599页

作者： E.B.Ryu j.m.chang m.Seo S.A.Kim j.H.Lim W.K.moon 尹训涛 Department of Radiology Seoul National University College of Medicine28 Yongon-dongChongno-guSeoul 110-744Korea

摘要目的使用连续超声评估乳腺癌各分子亚型的肿瘤体积倍增时间（TVDT）。方法本研究纳入66例未采取干预措施的浸润性乳腺癌病人（年龄:28;8岁,平均:50岁）行

关键词：分子亚型肿瘤体积倍增时间乳腺癌乳腺肿瘤超声

导管原位癌的乳腺钼靶片钙化特征:与雌激素受体(ER)及人类表皮生长因子受体2(HER2)表达情况的关系

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国际医学放射学杂志 2013年第5期 499-500页

作者： m.S.Bae W.K.moon j.m.chang N.Cho S.Y.Park j.K.Won 杨绮华 Department of Radiology Seoul National UniversityCollege of Medicine

摘要目的本研究探讨导管原位癌（DCIS）在乳腺钼靶片钙化的恶性可能（POm）与雌激素受体（ER）及人类表皮生长因子受体2（HER2）表达情况的关系。方法本研究纳入了101例（27;3岁）在乳腺钼靶片表现为钙化的单纯性DCIS女性病人。3名放射... 详细信息

摘要目的本研究探讨导管原位癌（DCIS）在乳腺钼靶片钙化的恶性可能（POm）与雌激素受体（ER）及人类表皮生长因子受体2（HER2）表达情况的关系。方法本研究纳入了101例（27;3岁）在乳腺钼靶片表现为钙化的单纯性DCIS女性病人。3名放射科医师根据BI-RADS系统分别阅片并且进行满分为100分的POm评分以及BI-RADS分类。ER、HER2以及乳腺癌的组织学亚型根据免疫组织化学法（IHC）以及免疫原位杂交法（FISH）确定。对比POm与IHC标记物的相关性及乳腺癌各种亚型在乳腺钼靶片上的特点。结果

关键词：乳腺钼靶 DCIS 原位癌 HER2 人类表皮生长因子受体雌激素受体 ER 导管木质部

Effect of heat treatment on microstructure and mechanical properties of selective laser-melted PH13-8mo stainless steel

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journal of Iron and Steel Research International 2024年第4期31卷 945-955页

作者： Yuan Zhang Xiang Liu chang-jun Wang chang Liu School of material Science and Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina Central Iron&Steel Research Institute Co. Ltd.Beijing 100081China

PH13-8mo stainless steel powder with high sphericity and well fluidity was prepared by the plasma rotating electrode *** formed parts with ultra-high purity were manufactured by selective laser *** tensile and impact mechanical properties of the printed parts under three heat treatment regimes were compared to those without heat *** microstructure,grain orientation and phase composition were characterized by electron-backscatter diffraction,X-ray diffraction and transmission electron *** characterization results reveal that the addition of heat treatment makes the grains enlarge,and after different heat treatments,the average grain size from 1.51μm in the printed state increases to 2.78,3.09 and 2.06μm,*** formed parts are mainly composed of martensite and retained ***,the NiAl and m23C precipitates form,which are the major strengthening phases of PH13-8mo stainless *** optimal heat treatment process is 925℃×1 h water cooling(WC)+0℃×2 h air cooling(AC)+540℃×4 h *** this heat treatment process,PH13-8mo formed parts have the optimal comprehensive mechanical properties:the tensile strength,yield strength and impact energy KU2 are 1492 mPa,1432 mPa and 63 j,*** strengthening and toughening via heat treatment are mainly attributed to dislocation strengthening,the formation of NiAl and m23Co precipitates and the change of volume fraction of the retained austenite.

关键词： High-strength stainless steel-Selective laser melting-Heat treatment microstructure mechanical property

Generic modeling and Control Framework for Power Systems Dominated by Power Converters Connected Through a Passive Transmission and Distribution Grid

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CSEE journal of Power and Energy Systems 2024年第1期10卷 292-301页

作者： Qing-chang Zhong marcio Stefanello Department of Electrical and Computer Engineering Illinois Institute of TechnologyChicagoIL 60616USA Syndem LLC USA.M.Stefanello is with the Fundacao Universidade Federal do Pampa at AlegreteRS97546-550Brazil

In this paper,a compact mathematical model having an elegant structure,together with a generic control framework,are proposed for generic power systems dominated by power converters that are interconnected through a passive transmission and distribution(T&D)grid,by adopting the port-Hamiltonian(pH)systems theory and the fundamental circuit *** models of generic T&D lines are developed and then the model of a generic T&D grid is *** the proposed control framework,the controlled converters are proven to be passive and Input-to-State Stable(ISS).The compact mathematical model is scalable and can be applied to power systems with multiple power electronic converters with generic passive controllers,passive local loads,and different types of passive T&D lines connected in a meshed configuration without self-loops,so it is very ***,the resulting power system is proven to be ISS as *** analysis is carried out without assumptions on constant frequency/voltage,constant loads,and/or lossless networks,except the need of passivity for all parts involved,and without using the Clarke/Park transformations or the graph *** simplify the presentation,three-phase balanced systems are adopted but the results can be easily adapted for single-phase or unbalanced three-phase systems.

关键词： Input-to-State Stable(ISS) passivity,portHamiltonian(pH)systems Power electronic converters dominated power systems Synchronized and Democratized(SYNDEm)grid architecture

Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.j.mAHmOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COmSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

Greedy Lattice Paths with General Weights

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Acta mathematica Sinica,English Series 2024年第9期40卷 2213-2222页

作者： Yin Shan chang An Qi ZHENG College of mathematics Sichuan UniversityChengdu 610065P.R.China

Let{X_(v):v∈Z^(d)}be *** *** S(π)=Σ_(v∈π)X_(v)be the weight of a self-avoiding lattice pathπ.Let m_(n)=max{S(π):πhas length n and starts from the origin}.We are interested in the asymptotics of mn as n→∞.This model is closely related to the first passage percolation when the weights{X_(v):v∈Z^(d)}are non-positive and it is closely related to the last passage percolation when the weights{X_(v):v∈Z^(d)}are *** general weights,this model could be viewed as an interpolation between first passage models and last passage ***,this model is also closely related to a variant of the position of right-most particles of branching random *** the two assumptions that∃α>0,E(X_(0)^(+))^(d)(log^(+)X_(0)^(+))^(d+α)mber m such that mn/n converges to a deterministic constant m in L^(1)as n tends to *** under the stronger assumptions that∃α>0,E(X_(0)^(+))^(d)(log^(+)X_(0)^(+))^(d+α)m_(n)/n converges to the same constant m almost surely as n tends to infinity.

关键词： Last passage percolation first passage percolation greedy lattice path

Addressable structured light system using metasurface optics and an individually addressable VCSEL array

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Photonics Research 2024年第6期12卷 1129-1137页

作者： CHENYANG WU XUANLUN HUANG YIPENG jI TINGYU CHENG jIAXING WANG NAN CHI SHAOHUA YU CONNIE j.chang-HASNAIN School of Information Science and Technology Fudan UniversityShanghai 200433China Berxel Photonics Co. Ltd.Shenzhen 518071China Peng Cheng Laboratory Shenzhen 518055China Chinese University of Hong Kong Shenzhen 518172China

Structured-light(SL)based 3D sensors have been widely used in many *** SL is the most widely deployed among all SL sensors due to its light weight,compact size,fast video rate,and low *** transmitter(known as the dot projector)consists of a randomly patterned vertical-cavity surface-emitting laser(VCSEL)array multiplicated by a diffractive optical element(DOE)with a fixed repeated *** that the separation of any two speckles is only one known and fixed number(albeit random),there are no other known scales to cal-ibrate or ***,typical SL sensors require extensive in-factory calibrations,and the depth resolution is limited to 1 mm at-60 cm *** this paper,to the best of our knowledge,we propose a novel dot projector and a new addressable SL(ASL)3D sensor by using a regularly spaced,individually addressable VCSEL array,multiplicated by a metasurface-DOE(mDOE)into a random pattern of the *** turning on or off the VCSELs in the array provides multiple known distances between neighboring speckles,which is used as a“built-in caliper”to achieve higher accuracy of *** as a precise“vernier caliper,”the addressable VCSEL array enables fine control over speckle positions and high detection *** experimentally dem-onstrated that the proposed method can result in sub-hundred-micron level *** new concept opens new possibilities for applications such as 3D computation,facial recognition,and wearable devices.

关键词： speckle light surface

在数字乳腺摄影和数字乳腺断层摄影基础上增加乳腺超声筛查对普通风险女性乳腺癌筛查的必要性

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国际医学放射学杂志 2021年第3期44卷 351-351页

作者： A.Yi m.jang D.Yim B.R.Kwon m.S.U.Shin j.m.chang 范璐

摘要联合或非联合数字乳腺摄影(Dm)的数字乳腺断层摄影(DBT)是乳腺癌筛查的首选方式。然而,对于普通风险女性DBT筛查的充分性和增加全乳腺超声检查的必要性

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