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REITERATED HOMOGENIZATION OF NONLINEAR MONOTONE OpERATORS

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Chinese Annals of Mathematics,Series B 2001年第1期22卷 1-12页

作者： J.L.LIONS D.LUKKASSEN L.E.pERSSON p.wall CollegedeFrance 3rued＇Ulm75231Pariscedex05France NarvikInstituteofTechnologyandNorutTechnologyLtd. N-8505NarvikNorway DepartmentofMathematics LuleaUniversityofTechnologyS-97187LuleaSweden

In this paper, the authors study reiterated homogenization of nonlinear equations of the form --div(a(x, x/ε x/ε, Duε) = f, where a is periodic in the first two arguments and monotone in the third. It is proved that ue converges weakly in W1,p(Ω) (and even in some multiscale sense), as ε→ 0 to the solution uo of a limit problem. Moreover, an explicit expression for the limit problem is given. The main results were also stated in [15]. This article presents the complete proofs of these results.

关键词： Homogenization Nonlinear monotone operators Nonlinear equation

SUBCRITICAL TRANSITION IN pLANE pOISEUILLE FLOW

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SUBCRITICAL TRANSITION IN PLANE POISEUILLE FLOW

Effective Utilization of Government-provided CTI by Small Businesses within the Defense Industrial Base

第九届全国流体力学学术会议

作者： Masato Nagata Darren p.wall Department of Mechanics Tianjin University

Although the linear mechanism is bypassed in transition from the laminar state in plane poiseuille flow,the role of the nonlinear secondary flows that bifurcate from the linear neutral stability points,and the higher-order flows that in turn bifurcate from these flows,remains an open *** consider secondary and tertiary flows of this kind,thus re-examining and extending the problem previously considered by Ehrenstein & Koch(JFM 1991).The main conclusions of this previous study,that an’M(n;2m)’ solution branch could be continued down to Reynolds numbers at which transition is first observed with friction factor values corresponding to experimentally observed values are significantly revised by the present *** is demonstrated that the M(n;2m) solution does not exist,and that neither the Reynolds number nor friction factors of any of the tertiary flows corresponds to the first experimentally observed transition.

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Journal of Information Security 2024年第2期15卷 196-217页

作者： Josiah Dykstra Lawrence A. Gordon Martin p. Loeb Benjamin wall Lei Zhou National Security Agency Fort Meade MD USA Robert H. Smith School of Business University of Maryland College Park MD USA

There are two broad objectives of the research reported in this paper. First, we assess whether government-provided cyber threat intelligence (CTI) is helpful in preventing, or responding to, cyber-attacks among small businesses within the U.S. Defense Industrial Base (DIB). Second, we identify ways of improving the effectiveness of government-provided CTI to small businesses within the DIB. Based on a questionnaire-based survey, our findings suggest that government-provided CTI helps businesses within the DIB in preventing, or responding to, cyber-attacks providing a firm is familiar with the CTI. Unfortunately, a large percentage of small firms are not familiar with the government-provided CTI feeds and consequently are not utilizing the CTI. This latter situation is largely due to financial constraints confronting small businesses that prevent firms from having the wherewithal necessary to effectively utilize the government-provided CTI. However, we found a significant positive association between a firm’s familiarity with the government-provided CTI and whether a firm is being periodically reviewed by the Defense Counterintelligence and Security Agency (DCSA) or is compliant with the Cybersecurity Maturity Model Certification (CMMC) program. The findings from our study also show that the participating firms believe that external cyber threats are more likely to be the cause of a future cybersecurity breach than internal cybersecurity threats. Finally, our study found that the portion of the IT budget that small businesses within the DIB spend on cybersecurity-related activities is dependent on the perception that a firm would be the target of an external cyber-attack.

关键词： Government-provided CTI Small Businesses Defense Industrial Base

Enhanced entropy generation and heat transfer characteristics of magnetic nano-encapsulated phase change materials in latent heat thermal energy storage systems

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1051-1070页

作者： p.S.REDDY p.SREEDEVI Department of Mathematics Rajeev Gandhi Memorial College of Engineering and TechnologyNandyal 518501India

The objective of the current study is to investigate the importance of entropy generation and thermal radiation on the patterns of velocity,isentropic lines,and temperature contours within a thermal energy storage device filled with magnetic nanoencapsulated phase change materials(NEpCMs).The versatile finite element method(FEM)is implemented to numerically solve the governing *** effects of various parameters,including the viscosity parameter,ranging from 1 to 3,the thermal conductivity parameter,ranging from 1 to 3,the Rayleigh parameter,ranging from 102 to 3×10^(2),the radiation number,ranging from 0.1 to 0.5,the fusion temperature,ranging from 1.0 to 1.2,the volume fraction of NEpCMs,ranging from 2%to 6%,the Stefan number,ranging from 1 to 5,the magnetic number,ranging from 0.1 to 0.5,and the irreversibility parameter,ranging from 0.1 to 0.5,are examined in detail on the temperature contours,isentropic lines,heat capacity ratio,and velocity ***,the heat transfer rates at both the cold and hot walls are analyzed,and the findings are presented *** results indicate that the time taken by the NEpCMs to transition from solid to liquid is prolonged inside the chamber region as the fusion temperatureθf ***,the contours of the heat capacity ratio Cr decrease with the increase in the Stefan number Ste.

关键词： volume fraction of nano-encapsulated phase change material(NEpCM) radiation Stefan number heat capacity ratio entropy generation

A Hybrid Optimization Approach of Single point Incremental Sheet Forming of AISI 316L Stainless Steel Using Grey Relation Analysis Coupled with principal Component Analysiss

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 160-166页

作者： A Visagan p Ganesh Department of production Technology Madras Institute of TechnologyChennai-600044India

We investigated the parametric optimization on incremental sheet forming of stainless steel using Grey Relational Analysis(GRA) coupled with principal Component Analysis(pCA). AISI 316L stainless steel sheets were used to develop double wall angle pyramid with aid of tungsten carbide tool. GRA coupled with pCA was used to plan the experiment conditions. Control factors such as Tool Diameter(TD), Step Depth(SD), Bottom wall Angle(BWA), Feed Rate(FR) and Spindle Speed(SS) on Top.wall Angle(TWA) and Top.wall Angle Surface Roughness(TWASR) have been studied. wall angle increases with increasing tool diameter due to large contact area between tool and workpiece. As the step depth, feed rate and spindle speed increase,TWASR decreases with increasing tool diameter. As the step depth increasing, the hydrostatic stress is raised causing severe cracks in the deformed surface. Hence it was concluded that the proposed hybrid method was suitable for optimizing the factors and response.

关键词： single point incremental forming AISI 316L taguchi grey relation analysis principal component analysis surface roughness scanning electron microscopy

Cryogenic and conventional milling of AZ91 magnesium alloy

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Journal of Magnesium and Alloys 2024年第6期12卷 2503-2519页

作者： Vikas Marakini Srinivasa pai p Gururaj Bolar Bhaskara p Achar Department of Mechanical Engineering Nitte(Deemed to be University)NMAM Institute of Technology(NMAMIT)Nitte 574110India Department of Mechanical and Industrial Engineering Manipal Institute of TechnologyManipal Academy of Higher EducationManipal 576104India

Use of magnesium is the need of the hour due to its low density as well as its high strength-to-weight and stiffness-to-weight ratio *** study focuses on the effectiveness of liquid nitrogen(LN_(2))assisted cryogenic machining on the surface integrity(SI)characteristics of AZ91 magnesium *** milling using uncoated carbide inserts have been performed under liquid nitrogen(LN_(2))assisted cryogenic condition and compared with conventional(dry)*** are performed using machining parameters in terms of cutting speeds of 325,475,625 m/min,feed rates of 0.05,0.1,0.15 mm/teeth and depth of cuts of 0.5,1,1.5 mm *** significant surface integrity characteristics such as surface roughness,microhardness,microstructure,and residual stresses have been *** of SI characteristics with respect to milling parameters have been identified using statistical technique such as ANOVA and signal-to-noise(S/N)ratio ***,the multi criteria decision making(MCDM)techniques such as additive ratio assessment method(ARAS)and complex proportional assessment(COpRAS)have been utilized to identify the optimal conditions for milling AZ91 magnesium alloy under both dry and cryogenic *** of LN_(2)during machining,resulted in reduction in machining temperature by upto 29%with a temperature drop from 251.2℃under dry condition to 178.5℃in cryogenic *** showed the advantage of performing cryogenic milling in improving the surface integrity to a significant *** machining considerably minimized the roughness by upto 28%and maximised the microhardness by upto 23%,when compared to dry *** speed has caused significant impact on surface roughness(95.33%-dry,92.92%-cryogenic)and surface microhardness(80.33%-dry,82.15%-cryogenic).Due to the reduction in machining temperature,cryogenic condition resulted in compressive residual stresses(maximumσ║=-113 Mpa)on the alloy *** indicate no

关键词： Magnesium alloy Cryogenic machining Roughness Microhardness Microstructure Residual stress Multi criteria decision making

Widespread incomplete lineage sorting and introgression shaped adaptive radiation in the Gossypium genus

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plant Communications 2024年第2期5卷 185-197页

作者： Yanchao Xu Yangyang Wei Zhongli Zhou Xiaoyan Cai Scott ABoden Muhammad Jawad Umer Luqman BSafdar Yuling Liu Dingsha Jin Yuqing Hou Yuhong Wang Sarah Brooke wall Kunbo Wang Shuxun Yu Baohong Zhang Renhai peng Fang Liu National Key Laboratory of Cotton Bio-breeding and Integrated Utilization Institute of Cotton ResearchChinese Academy of Agricultural SciencesAnyang 455000China College of plant Science and Technology Huazhong Agricultural UniversityWuhan 40070China College of Biology and Food Engineering Anyang Institute of TechnologyAnyang 455000China National Nanfan Research Institute(Sanya) Chinese Academy of Agricultural SciencesSanya 572024China School of Agriculture Food and WineUniversity of AdelaideAdelaideSA 5005Australia Sanya Institute Hainan Academy of Agricultural SciencesSanya 572000China Department of Biology East Carolina UniversityGreenvilleNC 27858USA School of Agricultural Sciences Zhengzhou UniversityZhengzhou 450001China

Cotton(Gossypium)stands as a crucial economic crop,serving as the primary source of naturalfiber for the textile ***,the evolutionary mechanisms driving speciation within the Gossypium genus remain *** this investigation,we leveraged 25 Gossypium genomes and introduced four novel assem-blies—***,***,***,and ***(Gklo)—to delve into the speciation history of this ***,we encountered intricate phylogenies potentially stemming from *** complexities are further compounded by incomplete lineage sorting(ILS),a factor likely to have been instrumental in shaping the swift diversification of *** focus subsequently shifted to the rapid radiation episode during a concise period in Gossypium *** a recently diverged lineage comprising ***,Gklo,and ***,we constructed afinely detailed ILS ***,this analysis revealed the non-random distribution of ILS regions across the reference Gklo ***,we identified signs of robust natural selection influencing specific ILS *** variations per-taining to speciation emerged between the closely related sister species Gklo and ***-mately 15.74%of speciation structural variation genes and 12.04%of speciation-associated genes were esti-mated to intersect with ILS *** enrich our understanding of the role of ILS in adaptive radiation,shedding fresh light on the intricate speciation history of the Gossypium genus.

关键词： cotton speciation Gossypium genus incomplete lineage sorting ILS phylogenetic analysis gene tree resolution

The Dallas Donation after Circulatory Death Transplantation Summit:expanding donation after circulatory death procedures through process improvement,broader utilization,and innovation

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Hepatobiliary Surgery and Nutrition 2024年第5期13卷 824-836,I0009页

作者： Michele Finotti Anji wall Anthony D’Alessandro Gary Schwartz Chris Sonnenday David Goldberg Ashish Shah peter Friend Jeff p.Orlowski Greg McKenna Steve Newton Brad Adams William C.Chapman Amit Mathur Marwan Abouljoud Tim pruett Amelia Hessheimer James F.Trotter Sumeet K.Asrani Giuliano Testa Simmons Transplant Institute Baylor University Medical CenterDallasTXUSA Hepatobiliary and General Surgery Unit Regional Hospital TrevisoDISCOGUniversity of PaduaPaduaItaly Division of Transplantation Department of SurgeryUniversity of Wisconsin School of Medicine and Public HealthMadisonWIUSA Department of Thoracic Surgery and Lung Transplantation Baylor University Medical CenterCenter for Advanced Heart and Lung DiseaseDallasTXUSA Department of Surgery University of MichiganAnn ArborMIUSA Division of Digestive Health and Liver Diseases Department of MedicineUniversity of Miami Miller School of MedicineMiamiFLUSA Department of Cardio-Thoracic Surgery Vanderbilt University Medical CenterNashvilleTNUSA Nuffield Department of Surgical Sciences University of OxfordOxfordUK LifeShare Transplant Donor Services of Oklahoma Oklahoma CityOKUSA Administration Baylor University Medical CenterDallasTXUSA Southwest Transplant Alliance DallasTXUSA Department of Surgery/Transplantation Washington UniversitySt.LouisMOUSA Division of Transplant Surgery Department of SurgeryMayo Clinic ArizonaAlix School of MedicinePhoenixAZUSA Divisions of Transplant and Hepatobiliary Surgery Henry Ford HospitalDetroitMIUSA Department of Surgery University of MinnesotaMinneapolisMNUSA General and Digestive Surgery Hospital Universitario La PazIdiPAZMadridSpain

Despite a significant increase in utilization over the past decade,the number of donation after circulatory death(DCD)organs that are procured and transplanted in the United States(US)remains well below its *** is still room for expansion,as utilizing DCD organs to the fullest extent is currently the most viable solution to the persistent mismatch between supply and demand in *** convened a multidisciplinary transplantation summit to examine various aspects of DCD,with faculty members from around the world with clinical and academic interest in DCD donation and transplantation,including abdominal and cardiothoracic surgeons,organ procurement organization directors,hepatologists,and *** conference focused on identifying barriers to DCD organ utilization and strategies to overcome these *** divide the barriers to DCD utilization into three mains categories:(Ⅰ)policy and process variation;(II)logistical and transportation challenges;and(Ⅲ)higher risk perceptions related to DCD *** each barrier,we proposed a variety of solutions,providing an overview of the status of DCD donation in the US and suggestions on how to increase the use of *** is a specific focus on ex situ machine perfusion,normothermic regional perfusion,and other opportunities to expand DCD utilization without negatively impacting recipient outcomes.

关键词： Donation after circulatory death donation(DCD donation) marginal graft donor pool machine perfusion(Mp)

On the functions of astrocyte-mediated neuronal slow inward currents

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Neural Regeneration Research 2024年第12期19卷 2602-2612页

作者： Balázs pál Department of physiology Faculty of MedicineUniversity of DebrecenDebrecenHungary

Slow inward currents are known as neuronal excitatory currents mediated by glutamate release and activation of neuronal extra synaptic N-met hyl-D-aspartate receptors with the contribution of *** events are significantly slower than the excitatory postsynaptic *** of slow inward currents are determined by seve ral factors including the mechanisms of astrocytic activation and glutamate release,as well as the diffusion pathways from the release site towards the extra synaptic recepto *** are stimulated by neuronal network activity,which in turn excite neurons,forming an astrocyte-neuron feedback *** as a consequence of brain edema,astrocytic swelling can also induce slow inward currents under pathological *** is a growing body of evidence on the roles of slow inward currents on a single neuron or local network *** events often occur in synchro ny on neurons located in the same astrocytic *** synchronization of neuronal excitability,slow inward currents also set synaptic strength via eliciting timing-dependent synaptic *** addition,slow inward currents are also subject to non-synaptic plasticity triggered by long-la sting stimulation of the excitatory *** note,there might be important regionspecific differences in the roles and actions triggering slow inward *** greater networks,the pathophysiological roles of slow inward currents can be better understood than physiological *** inward currents are identified in the pathophysiological background of autism,as slow inward currents drive early hypersynchrony of the neural *** inward currents are significant contributors to paroxysmal depolarizational shifts/interictal *** events are related to epilepsy,but also found in Alzheimer's disease,parkinson's disease,and stroke,leading to the decline of cognitive *** with features overlapping with slow inward currents(excitatory,N-methyl-Dasp

关键词： astrocyte cortical spreading depolarization gliotransmission glutamate neural synchronization NMDA receptor paroxysmal depolarizational shift slow inward current