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Friction 2021年第6期9卷 1749-1765页

作者： K.e.Ch.VIDYASAgAR R.K.PANDeY Dinesh KALYANASUNDARAM Center for Biomedical engineering Indian Institute of Technology DelhiNew Delhi 110016India Department of Biomedical engineering College of EngineeringOsmania UniversityTelangana 500007India Department of Mechanical engineering Indian Institute of Technology DelhiNew Delhi 110016India Department of Biomedical engineering Indian Institute of Technology DelhiNew Delhi 110016India

In case of lightly loaded radial ball bearings,failure mechanisms other than fatigue such as smearing of raceways due to increased frictional torque and vibrations often ***,attempts have been made herein for reducing the frictional torque and minimizing the vibrations of a radial deep groove ball bearing employing surface textures at the inner *** pulsed laser was used to create texture(involving micro-dimples having different dimple area density)on the inner race of test *** an in-house developed test rig,frictional torque and vibrational parameters were measured at different speeds and light loads(*** vicinity of 0.01C,where C is dynamic load capacity of radial ball bearing).Significant reduction in frictional torque and overall vibrations were found in the presence of micro-dimples on inner race at light loads irrespective of operating *** without satisfying the minimum load needed criteria for the satisfactory operation,substantial reduction in smearing marks was found on the races of textured ball bearings in comparison to conventional cases.

关键词： ball bearing textured inner race grease lubricated frictional torque vibration

An Adjusted gray Map Technique for Constructing Large Four-Level Uniform Designs

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Journal of Systems Science & Complexity 2023年第1期36卷 433-456页

作者： eLSAWAH A M VISHWAKARMA g K MOHAMeD H S FANg Kai-Tai Department of Statistics and Data Science Faculty of Science and TechnologyBeijing Normal University-Hong Kong Baptist University United International CollegeZhuhai 519087China guangdong Provincial Key Laboratory of Interdisciplinary Research and Application for Data Science BNU-HKBU United International CollegeZhuhai 519087China Department of Mathematics Faculty of ScienceZagazig UniversityZagazig 44519Egypt Department of Mathematics&Computing Indian Institute of Technology DhanbadDhanbad 826004India College of Transportation and Civil engineering Fujian Agriculture and Forestry UniversityFuzhou 350002China The Key Lab of Random Complex Structures and Data Analysis The Chinese Academy of SciencesBeijing 100190China

A uniform experimental design(UeD)is an extremely used powerful and efficient methodology for designing experiments with high-dimensional inputs,limited resources and unknown underlying models.A UeD enjoys the following two significant advantages:(i)It is a robust design,since it does not require to specify a model before experimenters conduct their experiments;and(ii)it provides uniformly scatter design points in the experimental domain,thus it gives a good representation of this domain with fewer experimental trials(runs).Many real-life experiments involve hundreds or thousands of active factors and thus large UeDs are *** large UeDs using the existing techniques is an NP-hard problem,an extremely time-consuming heuristic search process and a satisfactory result is not *** paper presents a new effective and easy technique,adjusted gray map technique(AgMT),for constructing(nearly)UeDs with large numbers of four-level factors and runs by converting designs with s two-level factors and n runs to(nearly)UeDs with 2^(t−1)s four-level factors and 2tn runs for any t≥0 using two simple transformation *** justifications for the uniformity of the resulting four-level designs are given,which provide some necessary and/or sufficient conditions for obtaining(nearly)uniform four-level *** results show that the AgMT is much easier and better than the existing widely used techniques and it can be effectively used to simply generate new recommended large(nearly)UeDs with four-level factors.

关键词： Aberration adjusted gray map technique gray map technique Hamming distance moment aberration threshold accepting algorithm uniform design

Bulk etch rates of CR-39 at high etchant concentrations:diffusionlimited etching

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Nuclear Science and Techniques 2020年第12期31卷 41-49页

作者： e.M.Awad M.A.Rana Mushtaq Abed Al-Jubbori Physics Department Faculty of ScienceMenoufia UniversityShebin El-KoomMenoufia 32511Egypt MeRADD Instrumentation Control and Computer Complex(ICCC)PARAS Building18-KM Multan RoadP.O.ChungLahorePakistan Department of Physics College of Education for Pure SciencesUniversity of MosulMosul 41001Iraq

Systematic CR-39 bulk etching experiments were conducted over a wide range of concentrations(2–30 N)of NaOH-based *** analysis and a deep discussion of the results are presented.A comprehensive nuclear track chemical etching data bank was *** regimes of CR-39 bulk etching were *** I spans etchant concentrations from 2 to 12 *** II spans concentrations from 12 to 25 *** call this the dynamic bulk etching *** III is for concentrations greater than 25 *** this regime,the bulk etch rate is saturated with respect to the etchant *** classification is discussed and *** role of ethanol in NaOH-based etchants is explored and discussed.A parameter called the “reduced bulk etch rate” is defined here,which helps in analyzing the dependence of bulk etching on the amount of ethanol in the *** bulk etch rate shows a natural logarithmic dependence on the density of ethanol in the etchant.

关键词： CR-39 detector ethanol Bulk etch rate Reduced bulk etch rate Diffusion-limited etching Concentration-limited etching

STRATIFICATION BY SOLID PARTICLe SUSPeNSIONS

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Science China Mathematics 1989年第11期32卷 1325-1332页

作者：鄂学全 e.J.HOPFINgeR Institute of Mechanics Academia Sinica Beijing 100080 PRC Institut

Turbulence was generated by an oscillating grid above a bed of sediment of spherical glass beads. As expected, part of the sediment was lifted up by the grid action and a suspension layer of depth D formed above the grid. This depth was found remaining independent of grid action but varying with the sediment layer depth when the grid action was kept constant. Volume concentration measurements show the existence of only weak concentration gradients over the layer depth with a rapid fall off in concentration at the outer edge. The theoretical analysis based on a concentration flux model is in good qualitative agreement with observations.

关键词： turbulence sediments stratification.

Multiphase-field modelling of concurrent grain growth and coarsening in complex multicomponent systems

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Journal of Materials Science & Technology 2020年第10期42卷 215-229页

作者： P.g.Kubendran Amos Ramanathan Perumal Michael Selzer Britta Nestler Institute of Applied Materials(1AM-CMS) Karlsruhe Institute of Technology(KIT)Strasse am Forum 776131 KarlsruheGermany Institute of Digital Materials Science(IDM) Karlsruhe University of Applied SciencesMoltkestr.3076133 KarlsruheGermany

Phase-field modelling of microstructural evolution in polycrystalline systems with phase-associated grains has largely been confined to continuum-field *** this study,a multiphase-field approach,with a provision for introducing grain boundary and interphase diffusion,is extended to analyse concurrent grain growth and coarsening in multicomponent polycrystalline microstructures with chemically-distinct *** effect of the number of phases and components on the kinetics of evolution is investigated by considering binary and ternary systems of duplex and triplex microstructures,along with a single phase *** is realised that the mere increase in the number of phases minimises the rate of concurrent grain growth and ***,the effect of components is substantially dependent on the respective kinetic *** work unravels that the disparity in the influence of phases and components is primarily due to the corresponding change introduced in the transformation *** the raise in number of phases convolutes the diffusion paths,the increase in number of component effects the rate of evolution through the interdiffusion,which introduces interdependency in the diffusing ***,the role of phase-fractions on the transformation rate of triplex microstructure is studied,and correspondingly,the interplay of interface-and diffusion-governed evolution is elucidated.A representative evolution of three-dimensional triplex microstructure with equal phase-fraction is comparatively analysed with the evolution of corresponding two-dimensional setup.

关键词： Concurrent grain growth and coarsening Duplex and triplex microstructure Microstructural coarsening Multiphase grain growth Multiphase-field modelling

Fiber Bundle Topology Optimization for Surface Flows

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Chinese Journal of Mechanical engineering 2024年第3期37卷 236-264页

作者： Yongbo Deng Weihong Zhang Jihong Zhu Yingjie Xu Jan g Korvink State Key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi’an 710072China Institute of Microstructure Technology(IMT) Karlsruhe Institute of Technology(KIT)Hermann-von-Helmholtzplatz 176344 Eggenstein-LeopoldshafenGermany

This paper presents a topology optimization approach for the surface flows on variable design *** this approach,the matching between the pattern of a surface flow and the 2-manifold used to define the pattern can be optimized,where the 2-manifold is implicitly defined on another fixed 2-manifold named as the base *** fiber bundle topology optimization approach is developed based on the description of the topological structure of the surface flow by using the differential geometry concept of the fiber *** material distribution method is used to achieve the evolution of the pattern of the surface *** evolution of the implicit 2-manifold is realized via a homeomorphous *** design variable of the pattern of the surface flow and that of the implicit 2-manifold are regularized by two sequentially implemented surface-PDe *** two surface-PDe filters are coupled,because they are defined on the implicit 2-manifold and base manifold,*** surface Navier-Stokes equations,defined on the implicit 2-manifold,are used to describe the surface *** fiber bundle topology optimization problem is analyzed using the continuous adjoint method implemented on the first-order Sobolev *** numerical examples have been provided to demonstrate this approach,where the combination of the viscous dissipation and pressure drop is used as the design objective.

关键词： Fiber bundle Topology optimization 2-manifold Surface flow Material distribution method Porous medium model

Asymptotic expansions of Transition Densities for Hybrid Jump-diffusions

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Acta Mathematicae Applicatae Sinica 2004年第1期20卷 1-18页

作者： Yuan-jinLiu g.Yin DepartmentofMathematics WayneStateUniversity.DetroitMI18202

A class of hybrid jump diffusions modulated by a Markov chain is considered in this work. The motivation stems from insurance risk models, and emerging applications in production planning and wireless communications. The models are hybrid in that they involve both continuous dynamics and discrete events. Under suitable conditions, asymptotic expansions of the transition densities for the underlying processes are developed. The formal expansions are validated and the error bounds obtained.

关键词： Markov chain jump diffusion hybrid model Poisson process asymptotic expansion

The impact of perioperative blood transfusions on short-term outcomes following hepatectomy

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Hepatobiliary Surgery and Nutrition 2018年第1期7卷 1-10页

作者： Julie Hallet Alyson L.Mahar Avery B.Nathens Melanie e.Tsang Kaitlyn A.Beyfuss Yulia Lin Natalie g.Coburn Paul J.Karanicolas Division of general Surgery Sunnybrook Health Sciences CentreTorontoONCanada Department of Surgery University of TorontoTorontoONCanada Department of Public Health Sciences Queen’s UniversityKingstonONCanada Division of Clinical Pathology Sunnybrook Health Sciences CentreTorontoONCanada Department of Laboratory Medicine and Pathobiology University of TorontoTorontoONCanada

Background:Bleeding and need for red blood cell transfusions(RBCT)remain a significant concern with *** carry risk of transfusion-related immunomodulation that may impact post-operative *** study soughs to assess the association between RBCT and post-hepatectomy ***:Using the American College of Surgeons National Surgical Quality Improvement Program(ACS-NSQIP)registry,we identified all adult patients undergoing elective hepatectomy over 2007–*** exposure groups were created based on *** outcomes were 30-day major morbidity and *** outcomes included 30-day system-specific morbidity and length of stay(LOS).Relative risks(RR)with 95%confidence interval(95%CI)were computed using regression *** analyses were conducted to understand how missing data might have impacted the ***:A total of 12,180 patients were *** those,11,712 met inclusion criteria,2,951(25.2%)of whom received *** morbidity occurred in 14.9%of patients and was strongly associated with RBCT(25.3%vs.11.3%;Ped patients had higher rates of 30-day mortality(5.6%vs.1.0%;Per adjustment for baseline and clinical characteristics,RBCT was independently associated with increased major morbidity(RR 1.80;95%CI:1.61–1.99),mortality(RR 3.62;95%CI:2.68–4.89),and 1.29 times greater LOS(RR 1.29;95%CI:1.25–1.32).Results were robust to a number of sensitivity analyses for missing ***:Perioperative RBCT for hepatectomy was independently associated with worse short-term outcomes and prolonged *** findings further the rationale to focus on minimizing RBCT for hepatectomy,when they can be avoided.

关键词： Transfusion blood bleeding red blood cells liver hepatectomy

Predictability between Sensory Factors and Physical Properties of Clothing during exercise in a Cold environment

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Journal of China Textile University(english edition) 1999年第4期16卷 66-72页

作者： KeighleyJ.H. MclntypeJ.e. HamptonI.F.g. LiY.

Subjective responses on 19 sensory descriptors were ob-tained by exposing subjects in a cold environment of 14℃and 32％ RH,wearing T-sbirts made from eight *** factors were extracted from the sensory re-sponses using factor *** the other hand,an ex-tensive range of fabric physical properties was tested onthe same eight types of fabric,including six types ofmeasurements on fabric transport properties and seventypes of measurements on fabric mechanical *** principal component analysis,ten independent factorswere extracted from the objectively measured physical properties. Canonical correlation analysis is applied to the sen-sory factors and the physical factors to study relation-ships between objective measurements of the physicalproperties of fabrics and subjective sensory *** canonical correlation coefficients were found to be highly significant(Pgt;0.97). Canonical redundancy analysis showed that canoni-cal variables of the objective physical factors

关键词： Sensory perceptions fabrics physical properties and predictability

Characterization of face-centered cubic structure and deformation mechanisms in high energy shot peening process of TC17

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Journal of Materials Science & Technology 2022年第15期110卷 136-151页

作者： C.Yang M.Q.Li Y.g.Liu School of Materials Science and engineering Northwestern Polytechnical UniversityXi’an 710072China

The face-centered cubic structure(fcc)and its deformation behaviors,as well as the distinctive role of fcc-Ti in nanocrystallization in TC17 subjected to high energy shot peening(HeSP),were investigated by using comprehensive high-resolution transmission electron microscopy(HRTeM).The results showed that there was a stress-induced fcc-Ti in TC17 with a lattice constant of 0.420–0.433 nm and the B-type orientation relationship between the hcp-Ti and the fcc-Ti as[2-1-10]_(hcp)//[-110]_(fcc)and(0001)_(hcp)//(111)_(fcc),which was accomplished by the gliding of Shockley partial dislocations with Burgers vector of 1/3[01-10]on the basal *** deformation twinning dominated the subsequent deformation of fcc-Ti,producing two types of{111}twins with different *** them,the I-type twin with complete structure was generated by successive gliding of Shockley partial dislocations with the same Burgers vector of 1/6[11-2].In contrast,the cooperative slip of three Shockley partials,whose sum of Burgers vectors was equal to zero,produced the II-type twin with zero net macroscopic *** then,the emission of Shockley partial with the Burgers vector of 1/6[11-2]on every three(111)fccplanes resulted in the formation of a 9R *** to the dissociation effect of lamellar fcc-Ti and the superior deformation ability of fcc structure,the occurrence of fcc-Ti effectively promoted surface nanocrystallization of TC17.

关键词： TC17 Severe plastic deformation Stress-induced phase transformation Deformation twinning Nanocrystallization