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Th. Ch.pman-Rich.rds Distrib.tion and its Relationsh.p to th. Generalized b.ta

Forest Ecosystems 2019年第3期6卷 219-235页

作者： jeffrey h.Gove Th.mas b.Lynch.Mark J.Ducey USDA Forest Service Northern Research Station271 Mast Road Durham 03824NHUSA Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater 74078OKUSA Department of Natural Resources and th. Environment University of New Hampshire114 James Hall Durham 03824NHUSA

b.ckground: Th. Ch.pman-Rich.rds distrib.tion is developed as a special case of th. equilib.ium solution to th. McKendrick-Von Foerster equation. Th. Ch.pman-Rich.rds distrib.tion incorporates th. vital rate assumptions of th. Ch.pman-Rich.rds growth.function, constant mortality and recruitment into th. math.matical form of th. distrib.tion. Th.refore, unlike 'assumed' distrib.tion models, it is intrinsically linked with.th. underlying vital rates for th. forest area under consideration. Meth.ds: It is sh.wn th.t th. Ch.pman-Rich.rds distrib.tion can b. recast as a sub.et of th. generalized b.ta distrib.tion of th. first kind, a rich.family of assumed prob.b.lity distrib.tion models with.known properties. Th.se known properties for th. generalized b.ta are th.n immediately availab.e for th. Ch.pman-Rich.rds distrib.tion, such.as th. form of th. compatib.e b.sal area-size distrib.tion. A simple two-stage procedure is proposed for th. estimation of th. model parameters and simulation experiments are conducted to validate th. procedure for four different possib.e distrib.tion sh.pes. Results: Th. simulations explore th. efficacy of th. two-stage estimation procedure;th.se cover th. estimation of th. growth.equation and mortality-recruitment derives from th. equilib.ium assumption. Th. parameter estimates are sh.wn to depend on b.th.th. sample size and th. amount of noise imparted to th. synth.tic measurements. Th. results vary somewh.t b. distrib.tion sh.pe, with.th. smaller, noisier samples providing less reliab.e estimates of th. vital rates and final distrib.tion forms. Conclusions: Th. Ch.pman-Rich.rds distrib.tion in its original form, or recast as a generalized b.ta form, presents a potentially useful model integrating vital rates and stand diameters into a flexib.e family of resultant distrib.tions sh.pes. Th. data requirements are modest, and parameter estimation is straigh.forward provided th. minimal recommended sample sizes are ob.ained.

关键词： Diameter distrib.tions Ch.pman-Rich.rds growth Generalized b.ta distrib.tion of th. first kind Maximum likelih.od McKendrick-Von Foerster equation Ph.siologically structured population model Size-structured distrib.tions

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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 b.gin 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 b. our th.rmal sh.ck experiments on alumina plates. Furth.rmore, th. proposed model can interpret ob.erved h.erarch.cal crack patterns for h.gh.temperature jump cases, and a th.ee-stage relation b.tween th. residual strength.and th. temperature difference. Th. prediction for crack spacing can guide th. b.omimetic th.rmal-sh.ckfailure proof design, in wh.ch.th. h.rd platelets smaller th.n th. predicted diffusion induced b. constant crack-spacing are emb.dded 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 b.ttery. Finally we present th. maximum normalized DISes for various geometry and b.undary conditions b. single-variab.e curves for th. stressindependent diffusion process and two-variab.e contour plots for th. stress-dependent diffusion process, wh.ch.can provideengineers and materialists a simple and easy way to quickly evaluate th. reliab.lity of related materials and devices.

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

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LONG-TERM VARIAb.LITY OF Th. INDIAN SUMMER MONSOON AND RELATED PARAMETERS

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Advances in Atmosph.ric Sciences 1988年第4期5卷 469-481页

作者： G. b. Pant,K. Rupa Kumar,b. Parth.sarath.,h. P. b.rgaonkar Indian Institute of Tropical Meteorology Pune-411005 India Indian Institute of Tropical Meteorology Pune-411005 India Indian Institute of Tropical Meteorology Pune-411005 India Indian Institute of Tropical Meteorology Pune-411005 India

Th. long-term variab.lity of th. Indian summer monsoon rain-fall and related regional and glob.l parameters are studied. Th. cub.c spline is used as a digital filter to smooth.th. h.gh.frequency signals in th. time series of th. various parameters. Th. length.of th. data series varies from 95 to 115 years during th. period 1871-1985. Th. parameters studied with.n th. monsoon system are: (a) monsoon rainfall of th. country as a wh.le; (b. numb.r of b.eak-monsoon days during July and August; (c) numb.r of storms/ depressions in b.y of b.ngal and Arab.an Sea during summer monsoon season; and (d) dates of onset of summer monsoon over South.Kerala Coast. Th. parameters studied outside th. monsoon system are: (a) th. Wrigh.'s South.rn Oscillation Index (June-July-August); (b. th. January mean North.rn h.misph.ric surface air temperature anomaly; and (c) th. East-equatorial Pacific sea surface temperature *** order to examine th. variab.lity under various degrees of th. smooth.ng, th. series are filtere

关键词：口口 LONG-TERM VARIAb.LITY OF Th. INDIAN SUMMER MONSOON AND RELATED PARAMETERS VRF b.y

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Study of th. Unsteady Condensation of Moist Air in Sh.ck Tub.

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Journal of Th.rmal Science 2004年第3期13卷 235-244页

作者： S.-C. b.EK S.-b. KWON h.-D. KIM T. SETOGUCh. S. MATSUO Department of Mech.nical Engineering Kyungpook National University 1370 Sankyuk-dong Daegu 702-701 Korea Sch.ol of Mech.nical Engineering Andong National University Songchun-dong Andong 760-749 Korea Department of Mech.nical System Engineering Saga University 1 Honjo Saga 840-8502 Japan

Th. major flow ph.sics of th. unsteady condensation in th. sub.onic flows induced b. th. unsteady expansion waves in sh.ck tub. was studied in th.s paper. Th. unsteady condensation ph.nomenon was analyzed b. using th. two-dimensional, unsteady, Navier-Stokes equations, wh.ch.were fully coupled with.a droplet growth.equation. Th. th.rd-order TVD MUSCL sch.me was applied to solve th. governing equation systems. Th. computational results were compared with.th. previous experimental data. Th. time-dependent b.h.vior of unsteady condensation of moist air in sh.ck tub. was investigated in details. Th. results sh.w th.t th. major ch.racteristics of th. unsteady condensation ph.nomenon in sh.ck tub. are very different from th.se in th. supersonic wind tunnels.

关键词： sh.ck tub. sh.ck wave expansion wave unsteady flow compressib.e flow unsteady condensation

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Amb.ent air pollution and lung disease in Ch.na： h.alth.effects, study design approach.s and future research

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Frontiers of Medicine 2015年第3期9卷 392-400页

作者： jeffrey h. Mandel Ch.istine Wendt Ch.rles Lo Guangb.ao Zh.u Marsh.ll h.rtz Gurumurth. Ramach.ndran University of Minnesota Sch.ol of Pub.ic h.alth Minneapolis MN 55455 USA University of Minnesota Medical Sch.ol Veteran 's Administration Hospital Minneapolis MN 55455 USA University of Minnesota Mechanical Engineering Department Minneapolis MN 55455 USA State Key Lab.ratory of b.omemb.ane and Memb.ane b.otech.ology Institute of Zoology Chinese Academy of Sciences Beij ing 100101 China University of Minnesota Medical Sch.ol Minneapolis MN 55455 USA

Amb.ent air pollution in Ch.na h.s worsened following dramatic increases in industrialization, automob.le use and energy consumption. Particularly b.th.rsome is th. increase in th. PM2.5 fraction of pollutants. Th.s fraction h.s b.en associated with.increasing rates of cardio-respiratory disease in Ch.na and elsewh.re. Amb.ent pollutant levels h.ve b.en describ.d in many of Ch.na＇s cities and are comparab.e to previous levels in south.rn California. Lung cancer mortality in Ch.na h.s increased since th. 1970s and h.s b.en h.gh.r in men and in urb.n areas, th. exact explanation for wh.ch.h.s not b.en determined. Th. estimation of individual risk for Ch.nese citizens living in areas of air pollution will require furth.r research. Occupational coh.rt and casecontrol designs each.h.ve unique attrib.tes th.t could make th.m h.lpful to use in th.s setting. Oth.r important future research.considerations include detailed exposure assessment and th. possib.e use of b.omarkers as a means to b.tter understand and manage th. th.eat posed b. air pollution in Ch.na.

关键词： air pollution PM2.5 lung disease study design epidemiology

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h.gh.r-Order Line Element Analysis of Potential Field with.Slender h.terogeneities

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Computers, Materials & Continua 2016年第3期51卷 145-161页

作者： h.-S.Wang h.Jiang b.Yang Sch.ol of Optoelectronics b.ijing Institute of Tech.ology Beijing 100081China Department of Mech.nical and Aerospace Engineering University of Texas at Arlington ArlingtonTX 76019USA State Key Lab.ratory of Digital Manufacturing Equipment and Tech.ology Huazhong University of Science and TechnologyWuhanHuBei 430074China

Potential field due to line sources residing on slender h.terogeneities is involved in various areas,such.as h.at conduction,potential flow,and *** dipolar line sources are eith.r prescrib.d or induced due to close interaction with.oth.r *** calculation requires a h.gh.r-order sch.me to take into account th. dipolar effect as well as net source *** th. present work,we apply such.a h.gh.r-order line element meth.d to analyze th. potential field with.cylindrical slender *** a b.nch.ark example of two parallel rods,we compare th. line element solution with.th. b.undary element solution to sh.w th. accuracy as a function in terms of rods ***,we use more complicated examples to demonstrate th. capab.lity of th. line element tech.ique.

关键词： Electrostatics h.at conduction Integral equation tech.ique Line element meth.d Mesh.reduction meth.d,Potential field prob.ems

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DISCRETE AND CONTINUUM MODELLING OF GRANULAR FLOW

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Ch.na Particuology 2005年第6期3卷 354-363页

作者： h. P. Zh. Y. h. Wu A. b. Yu Centre for Simulation and Modelling of Particulate Systems School of Materials Science and Engineenng the University of New South Wales Sydney NSW 2052 Australia Department of Math.matics and Statistics Curtin University of Technology Perth WA 6845 Australia

Th.s paper analyses th.ee popular meth.ds simulating granular flow at different time and length.scales： discrete element meth.d （DEM）, averaging meth.d and viscous, elastic-plastic continuum model. Th. th.oretical models of th.se meth.ds and th.ir applications to h.pper flows are discussed. It is sh.wn th.t DEM is an effective meth.d to study th. fundamentals of granular flow at a particle or microscopic scale. b. use of th. continuum approach. granular flow can also b. describ.d at a continuum or macroscopic scale. Macroscopic quantities such.as velocity and stress can b. ob.ained b. use of such.computational meth.d as FEM. h.wever, th.s approach.depends on th. constitutive relationsh.p of materials and ignores th. effect of microscopic structure of granular flow. Th. comb.ned approach.of DEM and averaging meth.d can overcome th.s prob.em. Th. approach.takes into account th. discrete nature of granular materials and does not require any glob.l assumption and th.s allows a b.tter understanding of th. fundamental mech.nisms of granular flow. h.wever, it is difficult to adapt th.s approach.to process modelling b.cause of th. limited numb.r of particles wh.ch.can b. h.ndled with.th. present computational capacity, and th. difficulty in h.ndling non-sph.rical particles. Furth.r work is needed to develoo an aoorooriate aooroach.to overcome th.se prob.ems.

关键词： granular flow h.pper flow discrete element meth.d average meth.d continuum approach

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Microstructures and Mech.nical Properties of Al/Mg Alloy Multilayered Composites Produced b. Accumulative Roll b.nding

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Journal of Materials Science & Tech.ology 2011年第1期27卷 15-21页

作者： h.S. Liu b. Zh.ng G.P. Zh.ng Sh.nyang National Lab.ratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Key Lab.ratory for Anisotropy and Texture of Materials of Ministry of Education School of Materials & Metallurgy Northeastern University Shenyang 110004 China

Al/Mg alloy multilayered composites were produced successfully at th. lower temperature（280 C） b. accumulative roll b.nding（ARb. processing *** microstructures of Al and Mg alloy layers were ch.racterized b. scanning electron microscopy and transmission electron *** h.rdness and th.ee-point b.nding tests were conducted to investigate mech.nical properties of th. *** is found th.t Vickers h.rdness,b.nding strength.and stiffness modulus of th. Al/Mg alloy multilayered composite increase with.increasing th. ARb.*** and crack propagation along th. interface are th. two main failure modes of th. multilayered composite sub.ected to b.nding *** and fracture mech.nisms of th. composite are analyzed.

关键词： Accumulative roll b.nding(ARb. Al/Mg alloy multilayered composite Ultra-fine grains h.rdness b.nding properties

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Oxidative leach.ng kinetics of molyb.enum-uranium ore in h.SO4 using h.O2 as an oxidizing agent

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Frontiers of Ch.mical Science and Engineering 2013年第1期7卷 95-102页

作者： T. A. Lash.en M. E. EI-Ah.ady h. b. h.ssib.A. S. h.lal Nuclear Materials Auth.rity Cairo Egypt Ch.mistry Department Faculty of Science Cairo University Giza Egypt

Th. processing of molyb.enum-uranium ore in a sulfuric acid solution using h.drogen peroxide as an oxidant h.s b.en investigated. Th. leach.ng temperature, h.drogen peroxide concentration, sulfuric acid concentration, leach.ng time, particle size, liquid-to-solid ratio and agitation speed all h.ve significant effects on th. process. Th. optimum process operating parameters were： temperature： 95℃; h.O2 concentration： 0.5 M; sulfuric acid concentration： 2.5 M; time： 2 h. particle size： 74 gm, liquid-to-solid ratio： 14 ： 1 and agitation speed： 600 rpm. Under th.se experimental conditions, th. extraction efficiency of molyb.enum was ab.ut 98.4%, and th. uranium extraction efficiency was ab.ut 98.7%. Th. leach.ng kinetics of molyb.enum sh.wed th.t th. reaction rate of th. leach.ng process is controlled b. th. ch.mical reaction at th. particle surface. Th. leach.ng process follows th. kinetic model 1 - （1-X）1/3 = kt with.an apparent activation energy of 40.40 kJ/mole. Th. temperature, concentrations of h.02 and h.SO4 and th. mesh.size are th. main factors th.t influence th. leach.ng rate. Th. reaction order in h.SO4 was 1.0012 and in h.02 it was 1.2544.

关键词： leach.ng of molyb.enum leach.ng of uranium kinetics

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Arrh.th.ogenic mech.nisms in ryanodine receptor ch.nnelopath.es

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Science Ch.na(Life Sciences) 2015年第1期58卷 54-58页

作者： Zh.O Yan-Ting VALDIVIA Carmen R. GURROLA Georgina b. h.RNNDEZ Jonath.n J. VALDIVIA h.ctor h. Center for Arrh.th.ia Research Department of Internal MedicineCardiovascular DivisionUniversity of Michigan

Ryanodine receptors(Ry Rs) are th. calcium release ch.nnels of sarcoplasmic reticulum(SR) th.t provide th. majority of calcium ions(Ca2+) necessary to induce contraction of cardiac and skeletal muscle *** th.ir intracellular environment,Ry R ch.nnels are regulated b. a variety of cytosolic and luminal factors so th.t th.ir output signal(Ca2+) induces finely-graded cell contraction with.ut igniting cellular processes th.t may lead to ab.rrant electrical activity(ventricular arrh.th.ias) or cellular *** importance of Ry R dysfunction h.s b.en recently h.gh.igh.ed with.th. demonstration th.t point mutations in RYR2,th. gene encoding for th. cardiac isoform of th. Ry R(Ry R2),are associated with.catech.laminergic polymorph.c ventricular tach.cardia(CPVT),an arrh.th.ogenic syndrome ch.racterized b. th. development of adrenergically-mediated ventricular tach.cardia in individuals with.an apparently normal *** we summarize th. state of th. field in regards to th. main arrh.th.ogenic mech.nisms triggered b. Ry R2 ch.nnels h.rb.ring mutations linked to *** CPVT mutations ch.racterized to date endow Ry R2 ch.nnels with.a gain of function,resulting in h.peractive ch.nnels th.t release Ca2+ spontaneously,especially during *** spontaneous Ca2+ release is extruded b. th. electrogenic Na+/Ca2+ exch.nger,wh.ch.depolarizes th. external memb.ane(delayed afterdepolarization or DAD) and may trigger untimely action ***,a rare set of CPVT mutations yield Ry R2 ch.nnels th.t are intrinsically h.po-active and h.po-responsive to stimuli,and it is unclear wh.th.r th.se ch.nnels release Ca2+ spontaneously during *** discuss novel cellular mech.nisms th.t appear more suitab.e to explain ventricular arrh.th.ias due to Ry R2 loss-of-function mutations.

关键词： ryanodine receptors CPVT sarcoplasmic reticulum cardiac arrh.th.ias

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