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Jon Kle.nbe.g的数学工作

数学译林 2009年第2期28卷 133-136页

作者： Ge.t-Martin Gre.e. john e. hopcroft Margare. H. Wright 高燕芳(译) 马守全(校) 陆柱家(校)

《美国数学会通讯（Notice. of the.AMS）》约请（几位专家写了）描述2006年Navanlinna（奈旺林纳）奖得主Jon Kle.nbe.g工作的文章．国际数学联盟也发布了（相关）新闻，刊登在《美国数学会通讯》2006年10月号上．

关键词：数学通讯学会美国

SWITCHING AND Se.Ue.CING AVAILABLe.THe.APIe. SO AS TO MAXIMIZe.A PATIe.T＇S e.Pe.Te. TOTAL LIFe.IMe

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Inte.national Journal of Biomathe.atics 2012年第4期5卷 113-125页

作者： john e. GOULIONIS De.artme.t of Statistics and Insurance.Scie.ce. Unive.sity of Pirae.s 80 Karaoli a Dimitriou Stre.t 18534 Pirae.s Greece

This pape. has focuse. on applying mathe.atical te.hnique. to addre.s fundame.tal que.tion in the.apy planning whe. to switch, and how to se.ue.ce.the.apie.. We.conside. switching and se.ue.cing available.the.apie. so as to maximize.a patie.t＇s e.pe.te. total life.ime. We.assume.knowle.ge.only about the.life.ime.distributions induce. by the.the.apie.. We.discuss a spe.ialization of this mode. that is tailore. to a fre.ue.tly re.ccurring type.of manage.e.t proble., whe.e.our goal is to de.e.mine.the.be.t timing for te.ting and tre.tme.t de.isions for patie.ts with ische.ic he.rt dise.se. Typically, de.isions are.made.with an ove.all, goal of maximizing the.patie.t＇s e.pe.te. life.ime.or quality-adjuste. life.ime.

关键词： e.pe.te. total life.ime mainte.ance ische.ic he.rt dise.se stochasticorde.ing re.ationships statistical distributions.

A FAST LAGRANGIAN SIMULATION Me.HOD FOR FLOW ANALYSIS AND RUNNe. De.IGN IN Pe.TON TURBINe.

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Journal of Hydrodynamics 2012年第6期24卷 930-941页

作者： ANAGNOSTOPOULOS john S. PAPANTONIS Dimitris e. School of Me.hanical e.gine.ring National Technical University of Athens

In the.pre.e.t work, an alte.native.nume.ical me.hodology is de.e.ope. for a fast and e.fe.tive.simulation and analysis of the.comple. flow and e.e.gy conve.sion in Pe.ton impulse.hydro turbine.. The.algorithm is base. on the.Lagrangian approach and the.unste.dy fre.-surface.flow during the.je.-bucke. inte.action is simulate. by tracking the.traje.torie. of re.re.e.tative.fluid particle. at ve.y low compute. cost. Mode.n re.re.sion tools are.imple.e.te. in a ne. parame.e.ization te.hnique.of the.inne. bucke. surface. Ke.-fe.ture.of the.mode. is the.introduction of additional te.ms into the.particle.motion e.uations to account for various hydraulic losse. and the.flow spre.ding, which are.re.ulate. and e.aluate. with the.aid of e.pe.ime.tal data in a Laboratory Pe.ton turbine. The.mode. is applie. to study the.je.-runne. inte.action in various ope.ation conditions and the. to pe.form nume.ical de.ign optimization of the.bucke. shape. using a stochastic optimize. base. on e.olutionary algorithms. The.obtaine. optimum runne. attains re.arkably highe. hydraulic e.ficie.cy in the.e.tire.load range. Finally, a ne. small Pe.ton turbine.（150 kW） is de.igne., manufacture. and te.te. in the.Laboratory, and its pe.formance.and e.ficie.cy ve.ify the.mode. pre.ictions.

关键词： Pe.ton turbine hydraulic e.ficie.cy Lagrangian simulation bucke. shape.parame.e.ization nume.ical de.ign optimization

25 Ye.rs of se.sory drive. the.e.ide.ce.and its wate.y bias

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Curre.t Zoology 2018年第4期64卷 471-484页

作者： Molly e. CUMMINGS john A. e.DLe. De.artme.t of Inte.rative.Biology University of Texas Austin TX 78712 USA School of Life.and e.vironme.tal Scie.ce. Deakin University Waurn Ponds VIC 3216 Australia

It has be.n 25ye.rs since.the.formalization of the.Se.sory Drive.hypothe.is was publishe. in the.Ame.ican Naturalist （1992）. Since.the., the.e.has be.n an e.plosion of re.e.rch ide.tifying its utility in contributing to our unde.standing of inte.- and intra-spe.ific variation in se.sory syste.s and signaling prope.tie.. The.main te.e. of Se.sory Drive.is that e.vironme.tal characte.istics will influe.ce.the.e.olutionary traje.tory of both se.sory （de.e.ting capabilitie.） and signaling （de.e.table.fe.ture. and be.aviors） traits in pre.ictable.dire.tions. We.re.ie. the.accumulating e.ide.ce.in 154 studie. addre.sing the.e.que.tions and cate.orize. the.r approach in te.ms of te.ting for e.vironme.tal influe.ce.on se.sory tuning, signal characte.istics, or both. For the.subse. of studie. that e.amine. se.sory tuning, the.e.was gre.te. support for Se.sory Drive.proce.se. shaping visual than auditory tuning, and it was more.pre.ale.t in aquatic than te.re.trial habitats. Te.re.trial habitats and visual traits we.e.the.pre.ale.t habitat and se.sory modality in the.104 studie. showing support for e.vironme.tal influe.ce.on signaling prope.tie.. An additional 19 studie. that found no supporting e.ide.ce.for e.vironme.tal influe.ce.on signaling traits we.e.all base. in te.re.trial e.osyste.s and almost e.clusive.y involve. auditory signals. Only 29 studie. e.amine. the.comple.e.coe.olutionary proce.s be.we.n se.sory and signaling traits and we.e.dominate. by fish visual communication. We.discuss biophysical factors that may contribute.to the.visual and aquatic bias for Se.sory Drive.e.ide.ce. as we.l as biotic factors that may contribute.to the.lack of Se.sory Drive.proce.se. in te.re.trial acoustic signaling syste.s.

关键词： animal communication se.sory drive se.sory e.ology se.ual se.e.tion

Improving Compute. Scie.ce.Curriculum and Te.ching in the.Ne. Information Age

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Frontie.s of Digital e.ucation 2024年第1期1卷 78-84页

作者： john e.hopcroft Yao Guo Pe.ing Unive.sity Beijing 100871China Corne.l Unive.sity IthacaNY 14853USA

This article.pre.e.ts the.progre.s of Proje.t 101,an initiative.starting from De.e.be. 2021,to im-prove.compute. scie.ce.curriculum and te.ching in top Chine.e.unive.sitie.,in orde. to me.t the.de.and of compute. scie.ce.e.uction in the.ne. information *** 101 aims at improving classroom te.ching,while.focusing on the.de.e.opme.t of core.course.,core.te.tbooks,core.practice.platforms,as we.l as core.fac-ulty *** pre.e.t an ove.vie. of the.organiza-tion and plan of Proje.t 101,as we.l as the.curre.t prog-re.s afte. two ye.rs’e.forts from the.working group of Proje.t ***,we.will also discuss te.tative.future.plans aiming at improving compute. scie.ce.e.ucation in a large.numbe. of unive.sitie. base. on the.curre.t re.ults.

关键词： Proje.t 101 curriculum de.ign e.ucation te.ching improve.e.t

e.fe.ts of mountain pine.be.tle.kille. fore.ts on source.wate. contributions to stre.mflow in he.dwate. stre.ms of the. Colorado Rocky Mountains

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Frontie.s of e.rth Scie.ce 2017年第3期11卷 496-504页

作者： Christine.e. We.Ne. john D. STe.NICK Wate.she. Scie.ce.Program College of Natural Resources Colorado State University Fort Collins CO 80523-1472 USA

Natural or human-influe.ce. disturbance. are.important to the.he.lth and dive.sity of fore.ts, which in turn, are.important to the.wate. quantity and quality e.porte. from a catchme.t. Howe.e., human-induce. disturbance. （pre.cribe. fire.and harve.ting） have.be.n de.re.sing, and natural disturbance. （fire. and inse.ts） have.be.n incre.sing in fre.ue.cy and se.e.ity. One.such natural disturbance.is the.mountain pine.be.tle.（MPB）, （De.clroctonus ponde.osae. an e.de.ic spe.ie.. A re.e.t e.ide.ic re.ulte. in the.mortality of millions of he.tare. of lodge.ole.pine.（Pinus contorta） fore.ts in Colorado, USA. Be.tle.induce. tre. mortality brings about change. to the.hydrologic cycle. including de.re.se. transpiration and inte.ce.tion with the.loss of canopy cove.. This study e.amine. the.e.fe.t of the.mountain pine.be.tle.kill on source.wate. contributions to stre.mflow in snowme.t- dominate. he.dwate. catchme.ts using stable.isotope. （2H and ~80） as trace.s. Study catchme.ts with varying le.e. of be.tle.kille. fore.t are. （6% to 97%） we.e.sample. for groundwate., surface.wate., and pre.ipitation. Stre.ms we.e.sample. to asse.s whe.he. be.tle.kille. fore.ts have.alte.e. source.wate. contributions to stre.mflow. Ground- wate. contributions incre.se. with incre.sing be.tle.kille. fore.t are. （p = 0.008）. Both rain and snow contributions we.e.ne.ative.y corre.ate. with be.tle.kille. fore.t are. （p = 0.035 and p = 0.011, re.pe.tive.y）. As the.be.tle.kille. fore.t are. incre.se., so doe. fractional groundwate. contribution to stre.mflow.

关键词： mountain pine.be.tle isotope.trace.s stre.m-flow ge.e.ation he.dwate.s

Proportional-inte.ral-de.ivative.control of nonline.r half-car e.e.tro-hydraulic suspe.sion syste.s

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Journal of Zhe.iang Unive.sity-Scie.ce.A(Applie. Physics & e.gine.ring) 2013年第6期14卷 401-416页

作者： john e. D. e.ORU Jimoh O. Pe.RO School of Me.hanical Aeronautical and Industrial Engineering University of the Witwatersrand Private Bag 03 WITS 2050 Johannesburg South Africa

This pape. pre.e.ts the.de.e.opme.t of a proportional-inte.ral-de.ivative.(PID)-base. control me.hod for application to active.ve.icle.suspe.sion syste.s (AVSS). This me.hod use. an inne. PID hydraulic actuator force.control loop, in combination with an oute. PID suspe.sion trave. control loop, to control a nonline.r half-car AVSS. Robustne.s to mode. unce.tainty in the.form of variation in suspe.sion damping is te.te., comparing pe.formance.of the.AVSS with a passive.ve.icle.suspe.sion syste. (PVSS), with similar mode. parame.e.s. Spe.tral analysis of suspe.sion syste. mode. output data, obtaine. by pe.forming a road input disturbance.fre.ue.cy swe.p, provide. fre.ue.cy re.ponse.plots for both nonline.r ve.icle.suspe.sion syste.s and time.domain ve.icle.re.ponse. to a sinusoidal road input disturbance.on a smooth road. The.re.ults show the.gre.te. robustne.s of the.AVSS ove. the.PVSS to parame.ric unce.tainty in the.fre.ue.cy and time.domains.

关键词： Force.control Proportional-inte.ral-de.ivative.(PID) control Nonline.r half-car Active.ve.icle.suspe.sion syste. (AVSS) Hydraulic actuator dynamics Mode. unce.tainty

Spe.tral signature. of hydrilla from a tank and fie.d se.ting

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Frontie.s of e.rth Scie.ce 2012年第4期6卷 453-460页

作者： Alfonso BLANCO john J. QU William e. ROPe. Ge.rge.Mason Unive.sity College of Science Department of Geography and Geoinforrnation Sciences 4400 University Drive Fairfax VA 22030 USA

The.invasion of hydrilla in many wate.ways has cause. significant proble.s re.ulting in high main- te.ance.costs for e.adicating this invasive.aquatic we.d. Pre.e.t ide.tification me.hods e.ploye. for de.e.ting hydrilla invasions such as ae.ial photography and vide.s are.difficult, costly, and time.consuming. Re.ote.se.sing has be.n use. for asse.sing we.lands and othe. aquatic ve.e.ation, but ve.y little.information is available.for de.e.ting hydrilla invasions in coastal e.tuarie. and othe. wate. bodie.. The.obje.tive.of this study is to construct a library of spe.tral signature. for ide.tifying and classifying hydrilla invasions. Spe.tral signature. of hydrilla we.e.colle.te. from an e.pe.ime.tal tank and fie.d locations in a coastal e.tuary in the.uppe. Che.ape.ke.Bay. The.e.me.sure.e.ts colle.te. from the.e.pe.ime.tal tank, re.ulte. in spe.tral signature. with an ave.age.pe.k surface.re.le.tance.in the.ne.r-infrare. （NIR） re.ion of 16% at a wave.e.gth of 818 nm. Howe.e., the.spe.tral me.sure. me.ts, colle.te. in the.e.tuary, re.ulte. in a ve.y diffe.e.t spe.tral signature.with two surface.re.le.tance.pe.ks of 6% at wave.e.gths of 725 nm and 818 nm. The.diffe.e.ce.in spe.tral signature. be.we.n site. are.a re.ult of the.compone.ts in the.wate. column in the.e.tuary be.ause.of incre.se. turbidity （e.g., nutrie.ts, dissolve. matte. and suspe.de. matte.）, and canopy be.ng lowe. （subme.ge.） in the.wate. column. Spe.tral signature. of hydrilla obse.ve. in the.tank and the.fie.d had similar characte.istics with low re.le.tance.in visible.re.ion of the.spe.trum from 400 to 700 nm, but high in the.NIR re.ion from 700 to 900 nm.

关键词： Che.ape.ke.Bay hydrilla spe.tral library spe.tral signature. ne.r-infrare. NDVI

Host-e.vironme.t mismatche. associate. with subalpine.fir de.line.in Colorado

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Journal of Fore.try Re.e.rch 2016年第5期27卷 1177-1189页

作者： Robin M. Re.ch john e. Lundquist Kristina Hughe. Colorado State.Unive.sity Fort Collins CO USA U.S. Fore.t Se.vice.Anchorage Anchorage AK 99501 USA

Subalpine.fir de.line.（SFD） has kille. more.tre.s in Colorado＇s high e.e.ation fore.ts than any othe. inse.t or dise.se.proble.. The.wide.pre.d nature.of this disorde. sugge.ts that the.cause.involve. climatic factors. We.e.amine. the.influe.ce.of varying combinations of ave.age.annual te.pe.ature.and pre.ipitation on the.incide.ce.and distribution of SFD. Climatic transition matrice. ge.e.ate. in this study indicate.that most he.lthy tre.s are.found in climatic zone. with mode.ate.to low te.pe.ature. and high pre.ipitation; whe.e.s, SFD occurs mostly in zone. of mode.ate.te.pe.ature. and mode.ate.pre.ipitation. The.contrasting distributions de.ine.an e.vironme.tal mismatch. Fore.ts matche. with favorable.climatic conditions thrive. those.that are.mismatche. can be.ome.vulne.able.to de.line.dise.se.

关键词： Abiotic disorde. Climate.stre.s High e.e.ation fore.ts Fore.t dise.se.- Subalpine.fir