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Science China Mathematics 2024年第1期67卷 187-210页

作者： Xiao Li Zhonghua Qiao Cheng Wang Department of Applied Mathematics The Hong Kong Polytechnic UniversityHong KongChina Department of Mathematics The University of MassachusettsNorth DartmouthMA 02747USA

In this paper,we study a second-order accurate and linear numerical scheme for the nonlocal CahnHilliard *** scheme is established by combining a modified Crank-Nicolson approximation and the Adams-Bashforth extrapolation for the temporal discretization,and by applying the Fourier spectral collocation to the spatial *** addition,two stabilization terms in different forms are added for the sake of the numerical *** conduct a complete convergence analysis by using the higher-order consistency estimate for the numerical scheme,combined with the rough error estimate and the refined *** regarding the numerical solution as a small perturbation of the exact solution,we are able to justify the discrete?^(∞)bound of the numerical solution,as a result of the rough error ***,the refined error estimate is derived to obtain the optimal rate of convergence,following the established?∞bound of the numerical ***,the energy stability is also rigorously proved with respect to a modified *** proposed scheme can be viewed as the generalization of the second-order scheme presented in an earlier work,and the energy stability estimate has greatly improved the corresponding result therein.

关键词： nonlocal Cahn-Hilliard equation second-order stabilized scheme higher-order consistency analysis rough and refined error estimate

Local Hybrid Linear State Estimation for Electric Power Systems Using Stream Processing

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1259-1268页

作者： Kang Sun Manyun Huang Zhinong Wei Yuzhang Lin Guoqiang Sun College of Energy and Electrical Engineering Hohai UniversityNanjing 210098China Department of Department of Electrical and Computer Engineering University of Massachusetts LowellLowell MA 01854USA IEEE

The increasing penetration of renewable energy resources with highly fluctuating outputs has placed increasing concern on the accuracy and timeliness of electric power system state estimation(SE).Meanwhile,we note that only a fraction of system states fluctuate at the millisecond level and require to be *** such,refreshing only those states with significant variation would enhance the computational efficiency of SE and make fast-continuous update of states ***,this is difficult to achieve with conventional SE methods,which generally refresh states of the entire system every 4–5 *** this context,we propose a local hybrid linear SE framework using stream processing,in which synchronized measurements received from phasor measurement units(PMUs),and trigger/timingmode measurements received from remote terminal units(RTUs)are used to update the associated local ***,the measurement update process efficiency and timeliness are enhanced by proposing a trigger measurement-based fast dynamic partitioning algorithm for determining the areas of the system with states requiring *** particular,non-iterative hybrid linear formulations with both RTUs and PMUs are employed to solve the local SE *** timeliness,accuracy,and computational efficiency of the proposed method are demonstrated by extensive simulations based on IEEE 118-,300-,and 2383-bus systems.

关键词： Fast dynamic partitioning local hybrid linear state estimation phasor measurement units stream processing timeliness trigger/timing-mode measurements

Vertical plane depth-resolved surface potential and carrier separation characteristics in flexible CZTSSe solar cells with over 12% efficiency

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Carbon Energy 2024年第3期6卷 36-52页

作者： Dae-Ho Son Ha Kyung Park Dae-Hwan Kim Jin-Kyu Kang Shi-Joon Sung Dae-Kue Hwang Jaebaek Lee Dong-Hwan Jeon Yunae Cho William Jo Taeseon Lee JunHo Kim Sang-Hoon Nam Kee-Jeong Yang Division of Energy Technology DGISTDaeguRepublic of Korea Research Center for Thin Film Solar Cells DGISTDaeguRepublic of Korea Department of Physics Ewha Womans UniversitySeoulRepublic of Korea Department of Physics Incheon National UniversityIncheonRepublic of Korea Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMassachusettsUSA

Cu2ZnSn(S,Se)4(CZTSSe)solar cells have resource distribution and economic *** main cause of their low efficiency is carrier loss resulting from recombination of photo-generated electron and *** overcome this,it is important to understand their electron-hole behavior *** determine the carrier separation characteristics,we measured the surface potential and the local current in terms of the absorber *** elemental variation in the intragrains(IGs)and at the grain boundaries(GBs)caused a band edge shift and bandgap(Eg)*** the absorber surface and subsurface,an upward Ec and Ev band bending structure was observed at the GBs,and the carrier separation was *** the absorber center,both upward Ec and Ev and downward Ec-upward Ev band bending structures were observed at the GBs,and the carrier separation was *** improve the carrier separation and suppress carrier recombination,an upward Ec and Ev band bending structure at the GBs is desirable.

关键词： carrier separation CZTSSe flexible solar cell local current surface potential

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结构化液体的设计、构筑与应用

高分子学报 2024年第5期55卷 485-508页

作者：封维潇 Thomas P.Russell 史少伟北京化工大学化工资源有效利用国家重点实验室北京软物质科学与工程高精尖创新中心北京100029 Department of Polymer Science and Engineering University of MassachusettsAmherstMassachusetts 01003

结构化液体是近年来基于二元流体体系,利用固体粒子液/液界面自组装和堵塞相变构筑的一类非平衡态软物质材料,兼具固体的结构稳定性和液体的流动性.然而,受限于组装基元和成型方法,制备具有精准结构的智能结构化液体及衍生功能材料仍面... 详细信息

结构化液体是近年来基于二元流体体系,利用固体粒子液/液界面自组装和堵塞相变构筑的一类非平衡态软物质材料,兼具固体的结构稳定性和液体的流动性.然而,受限于组装基元和成型方法,制备具有精准结构的智能结构化液体及衍生功能材料仍面临挑战.我们课题组在该领域开展了大量研究工作,在发展界面调控新机制,制备液体/固体新材料,以及实现材料器件新突破等方面取得了系列创新成果.本专论从固体粒子界面自组装机制出发,重点阐述了一种利用纳米粒子和聚合物液/液界面共组装制备纳米粒子表面活性剂,进而构筑结构化液体的普适策略;总结归纳了结构化液体在响应性调控、高效精准构筑以及功能材料制备等方面的研究进展;并对该领域面临的机遇和挑战做出展望.

关键词：结构化液体纳米粒子表面活性剂液/液界面自组装

Silicon-photonics-enabled chip-based 3D printer

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Light(Science & Applications) 2024年第7期13卷 1320-1330页

作者： Sabrina Corsetti Milica Notaros Tal Sneh Alex Stafford Zachariah A.Page Jelena Notaros Research Laboratory of Electronics Massachusetts Institute of TechnologyCambridgeMA 02139USA Department of Chemistry The University of Texas at AustinAustinTX 78712USA

Imagine if it were possible to create 3D objects in the palm of your hand within seconds using only a single photonic *** 3D printing has revolutionized the way we create in nearly every aspect of modern society,current 3D printers rely on large and complex mechanical systems to enable layer-by-layer addition of *** limits print speed,resolution,portability,form factor,and material *** there have been recent efforts in developing novel photocuring-based 3D printers that utilize light to transform matter from liquid resins to solid objects using advanced methods,they remain reliant on bulky and complex mechanical *** address these limitations,we combine the fields of silicon photonics and photochemistry to propose the first chip-based 3D *** proposed system consists of only a single millimeter-scale photonic chip without any moving parts that emits reconfigurable visible-light holograms up into a simple stationary resin well to enable non-mechanical 3D ***,we experimentally demonstrate a stereolithography-inspired proof-of-concept version of the chip-based 3D printer using a visible-light beam-steering integrated optical phased array and visible-light-curable resin,showing 3D printing using a chip-based system for the first *** work demonstrates the first steps towards a highlycompact,portable,and low-cost solution for the next generation of 3D printers.

关键词： printer printing visible

Health behavior outcomes in stroke survivors prescribed wearables for atrial fibrillation detection stratified by age

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Journal of Geriatric Cardiology 2024年第3期21卷 323-330页

作者： Joanne Mathew Jordy Mehawej Ziyue Wang Taylor Orwig Eric Ding Andreas Filippaios Syed Naeem Edith Mensah Otabil Alex Hamel Kamran Noorishirazi IrinaRadu Jane Saczynski David D.McManus Khanh-Van Tran Division of Cardiovascular Medicine Department of MedicineUniversity of Massachusetts Chan Medical SchoolLake Avenue NorthWorcesterUSA Department of Internal Medicine Central Michigan UniversityMount PleasantUSA Department of Pharmacy and Health Systems Sciences School of PharmacyNortheastern UniversityBostonUSA Department of Population and Quantitative Health Sciences University of Massachusetts Chan Medical SchoolLake Avenue NorthWorcesterUSA

BACKGROUND Smartwatches have become readily accessible tools for detecting atrial fibrillation(AF).There remains limited data on how they affect psychosocial outcomes and engagement in older *** examine the health behavior outcomes of stroke survivors prescribed smartwatches for AF detection stratified by *** We analyzed data from the Pulsewatch study,a randomized controlled trial that enrolled patients(≥50 years)with a history of stroke or transient ischemic attack and CHA2DS2-VASc≥*** participants were equipped with a cardiac patch monitor and a smartwatch-app dyad,while control participants wore the cardiac patch monitor for up to 44 *** evaluated health behavior parameters using standardized tools,including the Consumer Health Activation Index,the Generalized Anxiety Disorder questionnaire,the 12-Item Short Form Health Survey,and wear time of participants categorized into three age groups:Group 1(ages 50-60),Group 2(ages 61-69),and Group 3(ages 70-87).We performed statistical analysis using a mixedeffects repeated measures linear regression model to examine differences amongst age *** Comparative analysis between Groups 1,2 and 3 revealed no significant differences in anxiety,patient activation,perception of physical health and wear *** use of smartwatch technology was associated with a decrease in perception of mental health for Group 2 compared to Group 1(β=-3.29,P=0.046).CONCLUSION Stroke survivors demonstrated a willingness to use smartwatches for AF ***,among these study participants,the majority did not experience negative health behavior outcomes or decreased engagement as age increased.

关键词： prescribed stratified wear

Numerical Investigations on the Resonance Errors of Multiscale Discontinuous Galerkin Methods for One-Dimensional Stationary Schrödinger Equation

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Communications on Applied Mathematics and Computation 2024年第1期6卷 311-324页

作者： Bo Dong Wei Wang Department of Mathematics University of Massachusetts DartmouthNorth DartmouthMA02747USA Department of Mathematics and Statistics Florida International UniversityMiamiFL33199USA

In this paper,numerical experiments are carried out to investigate the impact of penalty parameters in the numerical traces on the resonance errors of high-order multiscale discontinuous Galerkin(DG)methods(Dong et *** J Sci Comput 66:321–345,2016;Dong and Wang in J Comput Appl Math 380:1–11,2020)for a one-dimensional stationary Schrödinger *** work showed that penalty parameters were required to be positive in error analysis,but the methods with zero penalty parameters worked fine in numerical simulations on coarse *** this work,by performing extensive numerical experiments,we discover that zero penalty parameters lead to resonance errors in the multiscale DG methods,and taking positive penalty parameters can effectively reduce resonance errors and make the matrix in the global linear system have better condition numbers.

关键词： Discontinuous Galerkin(DG)method Multiscale method Resonance errors One-dimensional Schrödinger equation

Rationale and design of Tenecteplase Reperfusion Therapy in Acute Ischaemic Cerebrovascular Events III (TRACE III): a randomised, phase III, open- label, controlled trial

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Stroke & Vascular Neurology 2024年第1期9卷 82-89页

作者： Yunyun Xiong Bruce C V Campbell Marc Fisher Lee H Schwamm Mark Parsons Hao Li Yuesong Pan Xia Meng Xingquan Zhao Yongjun Wang Neurology Beijing Tiantan HospitalBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina Department of Medicine and Neurology The University of MelbourneMelbourneVictoriaAustralia Neurology Beth Israel Deaconess Medical CenterBostonMassachusettsUSA Department of Neurology and Comprehensive Stroke Center Massachusetts General HospitalBostonMassachusettsUSA Department of Neurology University of New South Wales South Western Sydney Clinical SchoolLiverpoolNew South WalesAustralia

Background and purpose Recombinant human TNK tissue-type plasminogen activator(rhTNK-tPA)was not inferior to alteplase for ischaemic stroke within *** study aimed to investigate the efficacy and safety of rhTNK-tPA in patients who had an ischaemic stroke due to large vessel occlusion(LVO)of anterior circulation beyond *** and design Tenecteplase Reperfusion Therapy in Acute Ischaemic Cerebrovascular Events-III(TRACE III)is a multicentre,prospective,randomised,open-label,blind endpoint,controlled clinical *** who had an ischaemic stroke due to anterior circulation LVO(internal carotid artery,middle cerebral artery M1 and M2 segments)within 4.5–24hours from last known well(including wake-up stroke and no witness stroke)and with salvageable tissue(ischaemic core volume6s at 24 hours and NIHSS score change from baseline at *** outcomes are symptomatic intracerebral haemorrhage within 36 hours and mortality at 90 *** TRACE III will provide evidence for the efficacy and safety of rhTNK-tPA in patients who had an ischaemic strokes due to anterior circulation LVO beyond *** registration number NCT05141305.

关键词： Therapy random Rational

Antifouling Properties of Electrospun Polymeric Coatings Induced by Controlled Surface Morphology

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Energy & Environmental Materials 2024年第6期7卷 409-419页

作者： Fabio L.Favrin Lorenzo Zavagna Matteo Sestini Semih Esin Bahareh Azimi Massimiliano Labardi Mario Milazzo Giuseppe Gallone Giovanna Batoni Serena Danti Department of Civil and Industrial Engineering University of PisaLargo Lucio Lazzarino 256122PisaItaly Department of Translational Research and New Technologies in Medicine and Surgery University of Pisavia San Zeno 35-3956123PisaItaly Institute for Chemical and Physical Processes(IPCF) National Research Council(CNR)Pisa Research AreaVia Moruzzi 156124PisaItaly Department of Civil and Environmental Engineering Massachusetts Institute of Technology(MIT)Massachusetts Ave.77CambridgeMassachusetts 02139USA

Nosocomial infections affect implanted medical devices and greatly challenge their functional outcomes,becoming sometimes life threatening for the ***,aggressive antibiotic therapies are administered,which often require the use of last-resort drugs,if the infection is caused by multi-drug-resistant *** the risk of bacterial contamination of medical devices in the hospitals has thus become an emerging *** routes to control these infections are based on materials provided with intrinsic bactericidal properties(i.e.,chemical action)and on the design of surface coatings able to limit bacteria adhesion and fouling phenomena(i.e.,physical action),thus preventing bacterial biofilm ***,we report the development and validation of coatings made of layer-by-layer deposition of electrospun poly(vinylidene fluoride-co-trifluoro ethylene)P(VDF-TrFE)fibers with controlled orientations,which ultimately gave rise to antifouling *** obtained 10-layer surface morphology with 90°orientation fibers was able to efficiently prevent the adhesion of bacteria,by establishing a superhydrophobic-like behavior compatible with the Cassie-Baxter ***,the results highlighted that surface wettability and bacteria adhesion could be controlled using fibers with diameter comparable to bacteria size(i.e.,achievable via electrospinning process),by tuning the intra-fiber spacing,with relevant implications in the future design of biomedical surface coatings.

关键词： additive manufacturing Escherichia coli fibers Poly(vinylidene fluoride-cotrifluoro ethylene)P(VDF-TrFE) Pseudomonas aeruginosa superhydrophobic

High Order IMEX Stochastic Galerkin Schemes for Linear Transport Equation with Random Inputs and Diffusive Scalings

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Communications on Applied Mathematics and Computation 2024年第1期6卷 325-339页

作者： Zheng Chen Lin Mu Department of Mathematics University of Massachusetts Dartmouth285 Old Westport RoadDartmouth02747MAUSA Department of Mathematics University of GeorgiaAthens30602GAUSA

In this paper,we consider the high order method for solving the linear transport equations under diffusive scaling and with random *** tackle the randomness in the problem,the stochastic Galerkin method of the generalized polynomial chaos approach has been ***,the high order implicit-explicit scheme under the micro-macro decomposition framework and the discontinuous Galerkin method have been *** provide several numerical experiments to validate the accuracy and the stochastic asymptotic-preserving property.

关键词： Stochastic Galerkin scheme linear transport equations generalized polynomial approach stochastic asymptotic-preserving property