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h.t Data Identification with.Multiple Bloom Filters： Block-Level Decision vs I/O Request-Level Decision

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Journal of computer Science & Tech.ology 2018年第1期33卷 79-97页

作者： Dongch.l Park Weiping h. h. c. Du Division of computer and Electronic Systems Engineering Hankuk University of Foreign Studies Gyeonggi-do 17035 Korea Intel corporation Hillsboro OR 97124 U.S.A. Dell Storage Eden Prairie MN 55344 U.S.A. Department of computer Science and Engineering University of Minnesota-Twin Cities Minneapolis MN 55455 U.S.A.

h.t data identification is crucial for many applications th.ugh.few investigations h.ve examined th. subject. All existing studies focus almost exclusively on frequency. h.wever, effectively identifying h.t data requires equally considering recency and frequency. Moreover, previous studies make h.t data decisions at th. data block level. Such.a fine-grained decision fits particularly well for flash.based storage because its random access ach.eves performance comparable with.its sequential access. h.wever, h.rd disk drives （h.Ds） h.ve a significant performance disparity between sequential and random access. Th.refore, unlike flash.based storage, exploiting asymmetric h.D access performance requires making a coarse-grained decision. Th.s paper proposes a novel h.t data identification sch.me adopting multiple bloom filters to efficiently ch.racterize recency as well as frequency. consequently, it not only consumes 50% less memory and up to 58% less computational overh.ad, but also lowers false identification rates up to 65% compared with.a state-of-th.-art sch.me. Moreover, we apply th. sch.me to a next generation h.D tech.ology, i.e., Sh.ngled Magnetic Recording （SMR）, to verify its effectiveness. For th.s, we design a new h.t data identification based SMR drive with.a coarse-grained decision. Th. experiments demonstrate th. importance and benefits of accurate h.t data identification, th.reby improving th. proposed SMR drive performance by up to 42%.

关键词： h.t data bloom filter sh.ngled magnetic recording (SMR)

FLOW STRESS MODEL FOR h.RD mach.NING OF AISI h.3 WORK TOOL steEL

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Acta Metallurgica Sinica(English.Letters) 2005年第6期18卷 741-748页

作者： h. Yan J. h.a R. Sh.vpuri Sch.ol of Mech.nical-Electrical Engineering Nanchang University Nanchang 330029China Th. Oh.o State University Columbus OH 43210 USA

An approach.is presented to ch.racterize th. stress response of workpiece in h.rd mach.ning, accounted for th. effect of th. initial workpiece h.rdness, temperature, strain and strain rate on flow stress. AISI h.3 work tool steel was ch.sen to verify th.s meth.dology. Th. proposed flow stress model demonstrates a good agreement with.data collected from publish.d experiments. Th.refore, th. proposed model can be used to predict th. corresponding flow stress-strain response of AISI h.3 work tool steel with.variation of th. initial workpiece h.rdness in h.rd mach.ning.

关键词： flow stress model h.rd mach.ning AISI h.3 work tool steel

Quantitative law of diffusion induced fracture

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Acta Mech.nica Sinica 2016年第4期32卷 611-632页

作者： h.-J.Lei h.-L.Wang B.Liu c.-A.Wang AML CNMMDepartment of Engineering MechanicsTsinghua UniversityBeijing 100084China State Key Lab of New ceramics and Fine Processing Department of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Th.ough.dimension analysis, an almost analytical model for th. maximum diffusion induced stress（DIS）and critical temperature（or concentration） difference at wh.ch.cracks begin to initiate in th. diffusion process is developed. It interestingly predicts th.t th. spacing of diffusioninduced cracks is constant, independent of th. th.ckness of specimen and th. temperature difference. Th.se conclusions are validated by our th.rmal sh.ck experiments on alumina plates. Furth.rmore, th. proposed model can interpret observed h.erarch.cal crack patterns for h.gh.temperature jump cases, and a th.ee-stage relation between th. residual strength.and th. temperature difference. Th. prediction for crack spacing can guide th. biomimetic th.rmal-sh.ckfailure proof design, in wh.ch.th. h.rd platelets smaller th.n th. predicted diffusion induced by constant crack-spacing are embedded in a soft matrix, and, th.refore, no fracture will h.ppen. Th.s may guide th. design of th. th.rmal protection system and th. lith.um ion battery. Finally we present th. maximum normalized DISes for various geometry and boundary conditions by single-variable curves for th. stressindependent diffusion process and two-variable contour plots for th. stress-dependent diffusion process, wh.ch.can provideengineers and materialists a simple and easy way to quickly evaluate th. reliability of related materials and devices.

关键词： normalized h.erarch.cal contour spacing quickly lith.um validated battery constraint coordinate

Intermediate Energy coulomb Excitation of Neutron-Rich.Nuclei

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ch.nese Ph.sics Letters 2010年第3期27卷 104-107页

作者： Rajiv Kumar Rajesh.Kh.rab h. c. Sh.rma Department of Applied Sciences Haryana College of Technology and Management Kaithal-136027 India Department of Ph.sics Kurukshetra University Kurukshetra-136119 India

We reinvestigate th. collective effects of th. retardation as well as th. bending on th. coulomb excitation cross sections and also on th. B（E2） strength. of some neutron-rich.isotopes using th. intermediate energy coulomb excitation th.ory. It is found th.t th. B（E2） strength. extracted from th. experimental coulomb excitation cross section data get suppressed approximately by 6%. Furth.rmore, th. obtained B（E2） strength. in th. energy range 30-100 MeV/A are found to be in better agreement with.th. corresponding values known from oth.r sources, th.n th.se obtained by using th. recoil-corrected relativistic coulomb excitation th.ory.

关键词： Nuclear ph.sics

Dynamic stress concentration in an infinitely long cylindrical cavity due to a point sph.rical source embedded with.n a fluid-saturated poroelastic formation of infinite extent

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Applied Math.matics and Mech.nics(English.Edition) 2025年第1期46卷 139-156页

作者： h.h.SSEINI O.BALILASh.KI Department of Mech.nical Engineering Faculty of EngineeringGolestan University

Th. effects of a h.rmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely with.n a fluid-saturated poroelastic formation of infinite extent are examined th.oretically. It is assumed th.t th. source is located outside th. cavity at a specified distance from th. boreh.le axis. Th. magnitudes of th. h.op and radial stresses beside th. pore pressures exerted on th. interface and inside th. porous medium surrounding th. boreh.le are calculated and discussed. Biot's poroelastic modeling along with.th.ee types of boundary conditions for th. cylindrical interface including th. ideal fluid, empty boreh.le, and rigid inclusion with.a h.rd boundary is employed for th. analysis. Utilizing a proper translational addition th.orem for expressing th. incident sph.rical wave in terms of cylindrical wave expansions, th. proposed boundary conditions at th. interface are satisfied. Stresses are formulated by means of wave potential functions in a th.ee-dimensional(3D) manner. Th. effects of th. frequency and th. radial distance between th. source and boreh.le on th. induced stresses are examined for th. first cylindrical modes over frequency spectra. Two permeability conditions for th. interface and th.ee types of soils for th. porous formation are considered th.ough.ut th. analysis. To give an overall outline of th. study, a numerical example is presented. Th. results clearly indicate th.t th. distance is a key parameter and h.s considerable effects on th. induced stress values. In addition, th. interface permeability condition and soil ch.racteristics play an important role in determining th. dynamic response of th. boreh.le. Finally,th. obtained results are compared with.th. relevant analyses existing in th. literature for some limit cases, and good agreement is ach.eved.

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Design of a Biomimetic Skin for an Octopus-Inspired Robot - Part Ⅱ： Development of th. Skin Artefact

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Journal of Bionic Engineering 2011年第3期8卷 297-304页

作者： Jinping h.u Rich.rd h. c. Bonser George Jeronimidis centre for Biomimetics School of Construction Management and Engineering UniversiO~ of Reading Reading RG6 6A Y UK

In order to develop skin artefact for an octopus-inspired robot arm, wh.ch.is designed to be able to elongate 60% of its original length. silicone nlbber and knitted nylon sh.et were selected to manufacture an artificial skin, due to th.ir h.gh.r elastic strain and h.gh.flexibility. Tensile and scissors cutting tests were conducted to ch.racterise th. matrix and reinforcing materials and th. skin artefact. Material properties of th. individual and th. composite materials were compared with.th. measured properties of real octopus skin presented ill Part I. Th. Young＇s modulus of th. skin sh.uld be below 20 MPa and th. elastic strain range sh.uld be over 60%. Th. fracture tough.ess sh.uld be at least 0.9 kJ.m 2. Tubes made of th. skin artefact filled with.liquid were tested to study volume ch.nge under deformation. Finite element analysis model was developed to simulate th. material and arm structure under tensile loading. Results sh.w th.t th. skin artefact developed h.s similar mech.nical properties as th. real octopus skin and satisfies all th. design specifications of th. OcTOPUS robot.

关键词： octopus skin static tensile test tough.ess skin artefact nylon/silicone composite

Flow of a micropolar fluid in a micro-ch.nnel under th. action of an alternating electric field: Estimates of flow in bio-fluidic devices

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Journal of h.drodynamics 2015年第3期27卷 350-358页

作者： MISRA J.c. ch.NDRA S. h.RWIG h. centre for h.alth.are Science and Tech.ology Indian Institute of Engineering Science and Technology Department of Ph.sics Sabang S. K. Mahavidyalaya Vidyasagar University Institute of Th.rmo-Fluid Dynamics Technische Universitat Hamburg-Harburg

Th. paper is devoted to a study of th. electro-osmotic flow of a micropolar bio-fluid, wh.n th. flow takes place between two plates th.t are in a state of periodic vibrations. considering blood as a micropolar fluid, it is found th.t th. amplitude of oscillation of th. microparticles of blood increases wh.n th. micropolar effect is pronounced more and more and th.t a rise in Debyeh.ickel parameter enh.nces both.th. velocity and microrotation gradient. Th. results provide guidelines for th. improvement of design of bio-sensing and micro-fluidic devices. Th. study leads to th. conclusion th.t electrical double layers formed in th. vicinity of th. wall can significantly alter th. flow dynamics of ph.siological fluids in micro-bio-fluidic devices.

关键词： microrotation Electro-osmotic flow Debye-h.ickel parameter micropolar fluid

Developing Skin Analogues for a Robotic Octopus

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Journal of Bionic Engineering 2012年第3期9卷 385-390页

作者： Jinping h.u Rich.rd h. c. Bonser George Jeronimidis centre for Biomimetics School of Construction Management and Engineering University of Reading Reading RG6 6AY UK Sch.ol of Engineering and Design Brunel University Uxbridge Middlesex UB8 3PH UK

In order to fabricate a biomimetic skin for an octopus inspired robot, a new process was developed based on mech.nical properties measured from real octopus skin. Various knitted nylon textiles were tested and th. one of 10-denier nylon was ch.sen as reinforcement. A combination of Ecoflex 0030 and 0010 silicone rubbers was used as matrix of th. composite to obtain th. righ. stiffness for th. skin-analogue system. Th. open mould fabrication process developed allows air bubble to escape easily and th. artificial skin produced was th.n and waterproof. Material properties of th. biomimetic skin were ch.r- acterised using static tensile and instrumented scissors cutting tests. Th. Young＇s moduli of th. artificial skin are 0.08 MPa and 0.13 MPa in th. longitudinal and transverse directions, wh.ch.are much.lower th.n th.se of th. octopus skin. Th. strength.and fracture tough.ess of th. artificial skin, on th. oth.r h.nd are h.gh.r th.n th.se of real octopus skins. conically-sh.ped skin prototypes to be used to cover th. robotic arm unit were manufactured and tested. Th. biomimetic skin prototype was stiff enough.to maintain it conical sh.pe wh.n filled with.water. Th. driving force for elongation was reduced significantly compared with.previous prototypes.

关键词： biomimetic skin artefact octopus robot textile composite

cFD Simulation of a h.drogen/Argon Plasma Jet Reactor for coal Pyrolysis

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ch.mical Research.in ch.nese Universities 2004年第4期20卷 446-451页

作者： ch.N h. G. XIE K. c. Taiyuan University of Tech.ology Taiyuan University of Technology Taiyuan 030024 P. R. China City University London EC1V 0HB UKand Taiyuan 030024 P. R. China

A computational Fluid Dynamics(cFD) model was formulated for Dc arc h.drogen/argon plasma jet reactors used in th. process of th. th.rmal h.2/Ar plasma pyrolysis of coal to acetylene. In th.s model, fluid flow, convective h.at transfer and conjugate h.at conductivity are considered simultaneously. Th. error caused by estimating th. inner-wall temperature of a reactor is avoided. Th. th.rmodynamic and transport properties of th. h.drogen/argon mixture plasma system, wh.ch.are usually expressed by a set of discrete data, are fitted into expressions th.t can be easily implemented in th. program. Th. effects of th. turbulence are modeled by two standard k-εequations. Th. temperature field and velocity field in th. plasma jet reactor were calculated by employing SIMPLEST algorith.. Th. knowledge and insigh. obtained are useful for th. design improvement and scale-up of plasma reactors.

关键词： Plasma Reactor computational fluid dynamics coal pyrolysis