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Ch.nese j.urnal of Electrical Engineering 2024年第1期10卷 1-2页

作者： Li j. Mei h. Li S. Tianj.n University China Tsingh.a Sh.nzh.n International Graduate Sch.ol China Lanzh.u j.aotong University China

Th. rapid development of clean and renewable energy tech.ologies represented by wind and solar energy,as well as th. continuous growth.of load demand,h.ve put forward h.gh.r requirements for th. safe operation of th. power *** performance of power equipment based on traditional dielectric materials is often limited by various defects generated during molding,transportation,assembly,and operation,wh.ch.cannot meet th. reliability requirements of power systems in th. new *** detection is an essential tech.ical meth.d in industrial development,wh.ch.can detect and evaluate th. defect and damage status of in-service equipment,key components,and materials with.ut damaging th. obj.ct.

关键词： service Application operation

缺血性卒中后的院内医源性并发症和远期死亡率

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世界核心医学期刊文摘（神经病学分册） 2006年第3期2卷 56-57页

作者： bae h.-j. Yoon D.-S. Lee j. 高艳琼 Department of Preventive Medicine College of Medicine Korea University 126-305 5-ka Anam-dong Seongbuk-Gu Seoul South Korea

Background and Purpose-Inh.spital medical complications account for a considerable portion of death. during th. early stage of stroke. h.wever, relatively few studies h.ve examined th.ir long-term effects on mortality in stroke patients. Meth.ds -We prospectively and consecutively collected data on 579 patients with.acute isch.mic stroke from November 1998 to February 2001. Mortality was confirmed using national death.certificate data from 1999 to 2003. Results -During admission, one or more medical complications requiring intervention developed in 160 of th.se 579 patients (27.6%). For th.se 160 subj.cts, th. 30-day, 90-day, 1-year, 2-year, 3-year, and 4-year mortalities were 16.3, 29.4, 46.9, 55. 6, 61.3, and 70.7%, wh.reas th. mortality figures for th.se with.ut such.compli cations (n=419) were 1.4, 3.8, 8.8, 15.0, 19.1, and 22.4 (P h.log-ra nk test). To eliminate th. sh.rt-term effects of th.se complications and th.s r eveal th.ir long-term effects, we investigated differences in mortality versus th. presence of inh.spital complications at more th.n 30 days, 90 days, 1 year, 2 years, and 3 years after stroke, respectively. Cox’s proportional h.zard regr ession analysis was applied at th.se times after stroke and sh.wed th.t all h.za rd ratios of medical complications in terms of mortality were statistically larg er th.n one, regardless of adj.sting for effects of potential predictors on mort ality. Conclusions -Our study sh.ws th.t stroke patient mortality is influenced by inh.spital medical complications significantly up to th. ch.onic stage. Th.s finding suggests th.t th. appropriate prevention and management of inh.spital complications could improve sh.rtterm and long-term prognoses after stroke.

关键词：缺血性卒中内医远期效应秩和检验数据确认死亡证明慢性阶段上均

Th. quasi-Gramian solution of a non-commutative extension of th. h.gh.r-order nonlinear Sch.?dinger equation

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Communications in Th.oretical Ph.sics 2024年第3期76卷 51-61页

作者： h.W A Riaz j.Lin Department of Ph.sics Zhejiang Normal UniversityJinhua 321004China

Th. nonlinear Sch.?dinger(NLS)equation,wh.ch.incorporates h.gh.r-order dispersive terms,is widely employed in th. th.oretical analysis of various ph.sical *** th.s study,we explore th. non-commutative extension of th. h.gh.r-order NLS *** treat real or complex-valued functions,such.as g_(1)=g_(1)(x,t)and g_(2)=g_(2)(x,t)as non-commutative,and employ th. Lax pair associated with.th. evolution equation,as in th. commutation *** derive th. quasi-Gramian solution of th. system by employing a binary Darboux *** soliton solutions are presented explicitly with.n th. framework of *** visually understand th. dynamics and solutions in th. given example,we also provide simulations illustrating th. associated ***,th. solution can be used to study th. stability of plane waves and to understand th. generation of periodic patterns with.n th. context of modulational instability.

关键词： integrable systems Darboux transformation solitons

Convexification of h.brid AC-DC Optimal Power Flow with.Line-Commutated Converters

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CSEE j.urnal of Power and Energy Systems 2024年第2期10卷 617-628页

作者： h.ngyuan Liang Zh.gang Li j.h.Zh.ng Q.h.Wu Sch.ol of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

Line-commutated converter (LCC)-based h.gh.voltage DC (h.DC) systems h.ve been integrated with.bulk AC power grids for interregional transmission of renewable power. Th. nonlinear LCC model brings additional nonconvexity to optimal power flow (OPF) of h.brid AC-DC power grids. A convexification meth.d for th. LCC station model could address such.nonconvexity but h.s rarely been discussed. We devise an equivalent reformulation for classical LCC station models th.t facilitates second-order cone convex relaxation for th. OPF of LCC-based AC-DC power grids. We also propose sufficient conditions for exactness of convex relaxation with.its proof. Equivalence of th. proposed LCC station models and properties, exactness, and effectiveness of convex relaxation are verified using four numerical simulations. Simulation results demonstrate a globally optimal solution of th. original OPF can be efficiently obtained from relaxed model.

关键词： AC-DC power system convex relaxation linecommutated converter optimal power flow second-order cone programming

Decorating crystalline YFe_(2-x)Al_(x) on th. Mg_(60)La_(10)Ni_(20)Cu_(10) amorph.us alloy as “h.drogen pump” to realize fast de/h.drogenation

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j.urnal of Materials Science & Tech.ology 2024年第6期173卷 72-79页

作者： L.j.h.ang h.Wang L.Z.Ouyang M.Zh. h.j.Lin Sch.ol of Materials Science and Engineering Key Laboratory of Advanced Energy Storage Materials of Guangdong ProvinceSouth China University of TechnologyGuangzhou 510641China Institute of Advanced Wear&Corrosion Resistance and Functional Materials Jinan UniversityGuangzhou 510632China

Mg-based amorph.us alloys are one of th. potential h.drogen storage materials but suffer from sluggish.deh.drogenation/h.drogenation(de/h.drogenation)*** th.s work,as a new strategy,a h.drogen pump is built on th. surface of amorph.us alloys to solve th.s *** milling crystalline YFe_(2-x)Al_(x) h.drogen storage alloy with.Mg_(60)La_(10)Ni_(20)Cu_(10) amorph.us alloy,fine crystalline particles were seeded on amorph.us alloy powder to form a“strawberry”*** to th. TEM observation,a metallurgical bonding boundary formed between th. Mg-based amorph.us matrix and th. Y-Fe-Al crystalline *** microstructure and de/h.drogenation kinetics investigation,th.“h.drogen pump”effect of th. seeded crystalline alloy was confirmed,wh.ch.makes it much.easier for th. h.drogen to dissociate on and diffuse th.ough.th. surface of th. Mg-based amorph.us *** such.effect,th. h.absorption rate of Mg_(60)La_(10)Ni_(20)Cu_(10) amorph.us alloy became almost eigh. times faster and it absorbs ~2.8 wt.% in 1 h.at 130℃ under 4.5 MPa-h.(2).Furth.r,fast h.drogenation can even ach.eve at 70℃ and th. low-temperature deh.drogenation kinetics of th. amorph.us h.dride can be also greatly *** present work proves th.t surface modification is of great importance for obtaining Mg-based amorph.us alloy with.ideal h.drogen storage performance.

关键词： h.drogen storage Mg-based amorph.us alloy h.drogen pump Composite structure

Observability Analysis of Integrated Electricity and h.ating Systems with.Th.rmal Quasi-dynamics in Pipelines

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CSEE j.urnal of Power and Energy Systems 2024年第3期10卷 1145-1158页

作者： Zh.gang Li Wenj.an Zh.ng j.nbo Zh.o j.h.Zh.ng Q.h.Wu Sch.ol of Electric Power Engineering South China University of TechnologyGuangzhou 510641China Fuzh.u Ch.ngle District Power Supply Company of State Grid Fuj.an Electric Power Co. Ltd.Fuzhou 350000China Department of Electrical and Computer Engineering University of ConnecticutStorrsCT 06269USA CSEE IEEE

Observability analysis(OA)is vital to obtaining th. available input measurements of state estimation(SE)in an integrated electricity and h.ating system(IEh.).Considering th. th.rmal quasi-dynamics in pipelines,th. measurement equations in h.ating systems are dependent on th. estimated results,leading to an interdependency between OA and *** OA meth.ds require measurement equations be known exactly before SE is performed,and th.y are not applicable to *** bridge th.s gap,a scenario-based OA sch.me for IEh.s is devised th.t yields reliable analysis results for a predefined set of time-delay scenarios to cope with.th.s *** its core procedure,th. observable state identification and observability restoration are formulated in terms of integer linear *** tests are conducted to demonstrate th. validity and superiority of th. proposed formulation.

关键词： Integrated electricity and h.ating system measurement observability analysis state estimation th.rmal quasi-dynamics

Dissociation cross sections ofψ(3770),ψ(4040),ψ(4160),andψ(4415)mesons with.nucleons

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Communications in Th.oretical Ph.sics 2024年第4期76卷 93-112页

作者： Ruo-Qing Ding Xiao-Ming Xu h.j.Weber Department of Ph.sics Shanghai UniversityBaoshanShanghai 200444China Department of Ph.sics University of VirginiaCharlottesvilleVA 22904United States of America

We study th. dissociation of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons in collision with.nucleons, wh.ch.takes place in h.gh.energy proton-nucleus collisions. Th. quark interch.nge between a nucleon and a ■ meson leads to th. dissociation of th. ■ meson. We consider th. reactions:■, and■, wh.re R stands for ψ(3770), ψ(4040), ψ(4160), or ψ(4415). A reaction of a neutron and a ■ meson corresponds to a reaction of a proton and th. ■ meson by replacing th. up quark with.th. down quark and vice versa. Transition-amplitude formulas are derived from th. S-matrix *** cross sections are calculated with.th. transition amplitudes for scattering in th. prior form and in th. post form. Th. cross sections relate to nodes in th. radial wave functions of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons.

关键词： inelastic nucleon-ch.rmonium scattering quark interch.nge relativistic constituent quark potential model

Uncovering th. h.erarch.cal clusters in th. h.at-affected zone of an electron beam weldedα/βtitanium alloy j.int

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j.urnal of Materials Science & Tech.ology 2024年第7期174卷 120-132页

作者： C.Xu X.h.Sh.o h.j.Yang M.Lv h.Q.Liu X.L.Ma Sh.nyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Sch.ol of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Suzh.u laboratory Suzhou 215028China Department of Mech.nical Engineering Kyushu UniversityFukuoka 819-0395Japan Bay Area Center for Electron Microscopy Songshan Lake Materials LaboratoryDongguan 523808China

Using h.gh.resolution transmission Kikuch. diffraction(TKD)and transmission electron microscopy(TEM),we examined th. h.erarch.cal clusters th.t form in situ in th. h.at-affected zone(h.Z),wh.ch.are com-monly referred to as“gh.st”structures,of bimodal titanium alloy Ti-5Al-2Sn-2Zr-4Mo-4Cr(wt%,TC17).Th. gh.st structures are enrich.d with.Al elements but poor in Mo and Cr compared to th. surroundingβ*** results sh.w th.t th. gh.st structure in middle-h.Z mainly consists ofα_(L)lath. with.a h.gh.angle grain boundary,wh.ch.exh.bits th. classic Burgers orientation relationsh.p(BOR)with.th. h.st matrix,wh.le it encircles th.α_(P)grains in *** th. gh.st structure is evidenced to form via in-complete martensitic *** results furth.r confirm th.t th. gh.st structure is composed ofαL and tinyβ_(L)lath. with.BOR,with.th. former being enrich.d with.Al and poor with.Cr and Mo,wh.le th. latter is th. ***,twoα_(L)variant clusters with.a ch.ck-mark morph.logy are fre-quently observed viewed along[0001]_(αL)//[110]_(βL)directions,wh.ch.are dominated by th. crystallograph.c and geometrical relationsh.ps betweenαandβ*** on th. microstructural ch.racterization,it is h.poth.sized th.t th. gh.st structure is transformed from th. initialα_(P)ph.se,due to th. coupling ef-fect of h.gh.th.rmal stress(wh.ch.induces th. formation of a large number of dislocations)and element diffusion caused by sudden temperature increase and plunge cooling in th. h.Z during th. welding pro-cess.

关键词： TC17 titanium alloy Electron beam welding(EBW) Th. gh.st structure Transmission Kikuch. diffraction(TKD) Transmission electron microscopy(TEM)

On an isotropic porous solid cylinder:th. analytical solution and sensitivity analysis of th. pressure

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Applied Math.matics and Mech.nics(English.Edition) 2024年第9期45卷 1499-1522页

作者： h.ASGh.RI L.MILLER R.PENTA j.MERODIO Departamento de Matematica Aplicada a las TIC ETS de Ingenieria de Sistemas InformaticosUniversidad Politecnica de MadridMadrid 28031Spain Sch.ol of Math.matics and Statistics University of GlasgowGlasgow G128QQU.K.

With.n th.s work,we perform a sensitivity analysis to determine th. influence of th. material input parameters on th. pressure in an isotropic porous solid *** provide a step-by-step guide to obtain th. analytical solution for a porous isotropic elastic cylinder in terms of th. pressure,stresses,and elastic *** obtain th. solution by performing a Laplace transform on th. governing equations,wh.ch.are th.se of Biot's poroelasticity in cylindrical polar *** enforce radial boundary conditions and obtain th. solution in th. Laplace transformed domain before reverting back to th. time *** sensitivity analysis is th.n carried out,considering only th. derived pressure *** analysis finds th.t th. time t,Biot's modulus M,and Poisson's ratio ν h.ve th. h.gh.st influence on th. pressure wh.reas th. initial value of pressure P_(0) plays a very little role.

关键词： sensitivity analysis Laplace transform cylindrical polar coordinate Biot's modulus cylinder

Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mech.nisms

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j.urnal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： h.T.j.ong S.W.Lee W.j.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

Th. superplastic beh.vior and associated deformation mech.nisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with.a grain size of 3.2μm,primarily composed of th. BCCβph.se and a small amount of th. h.Pαph.se,were examined in a temperature range of 473 K to 623 *** microstructural refinement of th.s alloy was ach.eved by employing h.gh.ratio differential speed *** best superplasticity was ach.eved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),wh.re tensile elongations of 550±600%were *** th. h.ating and h.lding stage of th. tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider th.s effect wh.n analyzing and understanding th. superplastic deformation beh.vior and *** th. investigated strain rate range,th. superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,wh.le at h.gh.strain rates,lattice diffusion-controlled dislocation climb creep was th. rate-controlling deformation *** was concluded th.t solute drag creep is unlikely to *** th. late stages of deformation at 523 K,it was observed th.t grain boundary sliding led to th. agglomeration of th.αph.se,resulting in significant strain *** mech.nism maps were constructed forβ-Mg-Li alloys in th. form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using th. constitutive equations for various deformation mech.nisms derived based on th. data of th. current tests.

关键词： Magnesium-lith.um alloy Superplasticity Severe plastic deformation Grain size Grain growth