简介：曾经读到过这样一个故事：不少大屠杀的幸存者在二战后过上了富足的生活,但是他们中的一些人养成了奇怪的＂习惯＂——即便市场上商品并不短缺,也要往自己家冰箱里塞满食物。很多食物储藏久了就会过期甚至变质,但他们宁可把食物扔掉,也绝不能容忍缺少任何一点吃的东西。对这些当事人而言,饥饿的记忆是如此刻骨铭心,他们再也不能、也不想挨饿了。这个故事告诉我们,人的生活状态可以发生迅速的改变,但是心态却有惯性,其改变是存在延迟的。

简介：随着3+2高考的推行,历史,作为最具文科特色的科目之一,越来越受到众多考生的关注。尤其是近两年的高考中,历史考题十分灵活,不断地推陈出新,考出了其独有的特色和新意。作为95年江苏省高考文科状元,我想就如何学好历史、作最后冲刺谈谈自

简介：Asequentialextractionmethodforthefractionationofphosphorus(P)inlakesedimentswasusedtoanalyzephosphorusfractionsofsedimentstakenfromthreelarge,shallow,eutrophicfreshwaterlakesofChina-TaihuLake,ChaohuLake,andLongganLake.AllthreelakesarelocatedinthelowerreachesoftheChangjiangRiver(YangtzeRiver).InTaihuLakeandChaohuLake,algaebloomsoccurredeveryyear,whileLongganLakewasamacrophyte-dominatedlake.Resultsshowedthatexchangeablephosphorusfractionsweremuchhigherintheeutrophiclakesedimentsthaninthemacrophyte-flourishinglakesediment.Also,theratioofFe:Pinthesedimentsofthealgae-predominantlakeswasgenerallymuchlowerthanthatinthemacrophyte-predominantlakes.Thus,thegeochemicalfractionsofphosphorusinsedimentshadacloserrelationshipwiththetypeofaquaticvegetation.

简介：Asoneofthekeysafetyproblems,themotionperformanceandtouchingseabottomofaFPSOarepaidmuchattentionbytheoceanoilcompanieswhentheFPSOisexposedtosurvivalstormsintheshallow-waterworkingareas.Inthispaper,timedomainnumericalsimulationsarecarriedoutona160kDWTFPSOwithaYokemootingsystemmooredintheBZ25-1oilfieldwithawaterdepthof16.7m.Theresultsarecomparedwiththoseofthecorrespondingmodeltests.Goodagreementshowsthatthetime-domainsimulationscanbeusedtopredicttheperformanceoftheFPSOinshallow-waterreasonably.ItisfoundthatthetouchofseabedbyafullyloadedFPSOoccurredfewtimesundersurvivalstormconditions.Therefore,theFPSOshouldbelessloadedthanthatinthefullyloadedconditionunderthesurvivalstorms.

简介：such type of scheme is extnded to the 2D shallow water equations. A finite volume method on arbitrary quadrilateral elements is presented to solve shallow water flow problems with complex boundaries and having discontinuities.,A high-resolution finite volume numerical method for solving the shallow water equations is developed in this paper. In order to extend finite difference TVD scheme to finite volume method,Fig. 3(a) Water surface elevation for a rectangular dam-break Fig. 3(b) Contour of surface elevation for a rectangular dam-break

简介：Aquaticvegetationhasasignificantimpactonwatercurrents.Toevaluatetheeffectsofchangesintheaquaticvegetationonwatercurrentsofdifferentvelocity,a3-Dhydrodynamicmodelwasthendevelopedbytakingintoconsiderationoftheadditionalhydraulicresistanceoftheaquaticplants.TheNavier-StokesequationswerethensolvedusingtheSIMPLEmethodandthek-εturbulencemodel.CalculationsusingtheestablishedmodelswereusedtoforecasttheverticaldistributionofthehorizontalvelocityandhorizontalflowunderthetransmissionconditionsoftheSouth-NorthWaterDiversionintheNansiLake.Andcomparativecalculationfortheflowvelocitywasalsoperformedusingthesimplifiedmethodofassigningahighroughnesscoefficienttothelakebedinthesamearea.Resultssuggestthataddingadditionalhydraulicresistanceoftheaquaticplantsisfeasible.Thecalculationerrorsbetweensimulationresultandthefieldobserveddataaresmallerthan15%,while,thoseerrorsareupto35%iftheinfluenceofaquaticvegetationisdealtwiththesimplifiedmethod.

简介：Waveguideinvariantiswidelyusedinunderwatertargetpassiveranging.Inshallowwaterwithuniformsoundspeedprofile,thevalueofwaveguideinvariantisapproximatelyaconstant,whileinshallowwaterwiththermocline,itvariesinawiderange.Thewaveguideinvariantdistributionsandstriationsinthesetwoconditionsareanalyzedrespectively.Onthebasisofwavenumberdifferencebetweenreflectedmodesandrefractedmodes,awavenumber-frequencydomainfilteringtechniqueisproposedtoseparatethetwogroupsofmodes.Therequiredrelationshipbetweenarrayelementspace,totalarraylengthandtargetazimuthforeffectiveapplicationisdiscussed.Finally,thesimulationresultsindicatethatinshallowwaterwithathermocline,refractedmodescanbeeffectivelyfilteredoutusingthewavenumber-frequencydomainfilteringtechniqueandthetarget’srangeisestimatedaccurately.

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简介：Thenonlineardynamicalequationsofaxlesymmetryareestablishedbythemethodofquasi-shellsforthree-dimensionalshallowconicalsingle-layerlatticeshells.Thecompatibleequationsaregiveningeometricalnonlinearrange.AnonlineardifferentialequationcontainingthesecondandthethirdordernonlinearitemsisderivedundertheboundaryconditionsoffixedandclampededgesbythemethodofGalerkin.TheproblemofbifurcationisdiscussedbysolvingtheFloquetexponent.Inordertostudychaoticmotion,theequationsoffreeoscillationofakindofnonlineardynamicssystemaresolved.Thenanexactsolutiontononlinearfreeoscillationoftheshallowconicalsingle-layerlatticeshellisfoundaswell.ThecriticalconditionsofchaoticmotionareobtainedbysolvingMelnikovfunctions,somephaseplanesaredrawnbyusingdigitalsimulationprovingtheexistenceofchaoticmotion.

简介：ＮＯＮ－ＳＹＭＭＥＴＲＩＣＡＬＬＡＲＧＥＤＥＦＯＲＭＡＴＩＯＮＯＦＡＳＨＡＬＬＯＷＴＨＩＮＳＰＨＥＲＩＣＡＬＳＨＥＬＬＷａｎｇＸｉｎｚｈｉ（王新志）ＲｅｎＤｏｎｇｙｕｎ（任冬云）ＷａｎｇＬｉｎｘｉａｎｇ（王林祥）ＹｅｈＫａｉｙｕａｎ（叶开沅）（Ｇａｎ...

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简介：Theoreticalandexperimentalresearchoflowfrequencypulsecompressionandchannelmatchinshallowwatersoundchannelwerecarriedoutbasedon2000-WinterYellowSeaexperiment.Usingpulsecompressionmethod,signalswithhighsignaltonoiseratio(SNR)werereceivedoverrangeof110kilometersintheexperiment.TheSNRgainintheprocessisconsistentwiththetheoreticalprediction.Theexperimentalmeasurementindicatedthatthechannelishighlycoherentoveralengthof500s.ChannelmatchmethodwasusedtocompensatethedegradationofpulsecompressionSNRcausedbythemulti-pathpropagation.AndtheSNRgaininthechannelmatchprocesscanbetheoreticallypredicted.ExperimentalresultsshowthatlowfrequencypulsecompressionandchannelmatchmethodcanbeusedinshallowwatersoundchanneltoimprovetheSNR.

简介：Atpresent,thereislesstheoreticalresearchandpracticalexperienceintheaspectofultrashallowseismicexplorationtothetargetlayersatdepthsofonlytensofmetersbothathomeandabroad.Seismicexplorationplaysanimportantroleinthelocationoffaultsandactivestructures,butthedepthdozensofmetersbelowthegroundsurfaceistheblindareaofanykindofdeepandshallowseismicexploration.Startingfromthepointofviewofdetectingurbanactivefaults,andusingrelatedtheoriesandmethodsofgeology,geophysicsandmathematics,thepaperdiscussesthepreconditionsforacquiringefficientultra-shallowseismicsurveyresultsincomplicatedgeologicalbackgroundsinQingdao.TakingtheQingdaoareaasanexampleinthispaper,westudythedepthconditionofQuaternarydeposits,andapply4-8stackingfoldstosatisfytherequirementtogettheexplorationresultswithhigh-resolutionandhigh-SNR.Preliminaryresultsrevealthatselectingapropersurveillancelayoutisoneofthekeystoacquireauthenticexplorationresultsinultra-shallowP-wavereflectionexploration.OurresultsalsoshowthatultrashallowseismicreflectionmethodindetectingfaultsintheQingdaoareahasgoodapplicationprospects.

简介：ResistanceanalysisisanimportantanalyticalmethodusedtoevaluatethehydrodynamicperformanceofHighSpeedCraft(HSC).AnalysisofmultihullresistanceinshallowwaterisessentialtotheperformanceevaluationofanytypeofHSC.Shipsoperatinginshallowwaterexperienceincreasesinresistancebecauseofchangesinpressuredistributionandwavepattern.Inthispaper,theshallowwaterperformanceofanHSCdesignconcept,thesemi-SmallWaterplaneAreaTwinHull(semi-SWATH)form,isstudied.Thehullisinstalledwithfinstabilizerstoreducedynamicmotioneffects,andtheresistancecomponentsofthehull,hulltrimcondition,andmaximumwaveamplitudearoundthehullaredeterminedviacalmwaterresistancetestsinshallowwater.Thesecriteriaareimportantinanalyzingsemi-SWATHresistanceinshallowwateranditsrelationtoflowaroundhull.Theforefinangleisfixedtozerodegrees,whiletheaftfinangleisvariedto0o,5o,10o,and15o.Foreachconfiguration,investigationsareconductedwithdepthFroudenumbers(FrH)rangingfrom0.65to1.2,andtheresistancetestsareperformedinshallowwateratthetowingtankofUTM.Analysisresultsindicatethattheresistance,wavepattern,andtrimofthesemi-SWATHhullformareaffectedbythefinangle.Theresistanceisamplifiedwhereasthetrimandsinkagearereducedasthefinangleincreases.IncreasesinfinanglecontributetoseakeepingandstabilitybutaffectthehullresistanceofHSCs.

简介：潮汐的流动是一个周期的运动不稳定、不一致，它显然有加速和减速过程，特别在沿海的浅水里。潮汐的流动雷纳兹应力的垂直分发从线性分发背离了的许多研究表演。潮汐的流动雷纳兹压力的寓言的分发被歌等建议。(2009)。尽管模型更好充满领域观察和室内的试验性的数据，它有潮汐的流动雷纳兹应力的更低的截断的系列扩大，并且对分发的描述不是很全面的。由介绍潮汐的流动的运动方程并且改善，寓言的分发由歌等建立了。(2009)，潮汐的流动雷纳兹压力的立方的分发被建议。立方的分发被领域数据验证很好(Bowden和Fairbairn，1952；Bowden等，1959；Rippeth等，2002)并且试验性的数据(Anwar和阿特金斯，1980)，与Kuo等的数字模型结果一致。(1996)，并且与潮汐的流动雷纳兹压力的寓言的分发相比。这立方的分布比寓言的分发，而且罐头不仅好，这更好被显示出反映与潮汐的流动减速与潮汐的流动加速并且向上向下从线性分发背离的雷纳兹应力的基本特征，为潮汐的流动的速度侧面上的进一步的学习的基础。

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简介：广大退休人员既是和谐社会的构建者，又是和谐生活的共享者，无论是参与共建和谐社会，还是共享和谐社会的和谐生活，都需要有一个和谐的心态。现对退休人员的心态作一番诊断，并开出调和心态丹方若干。

简介：ＭＡＳＳＣＯＮＳＥＲＶＡＴＩＯＮＢＥＨＡＶＩＯＲＯＦＷＡＶＥＥＱＵＡＴＩＯＮＭＯＤＥＬＦＯＲＳＯＬＶＩＮＧＳＨＡＬＬＯＷＷＡＴＥＲＥＱＵＡＴＩＯＮ￥ＷｕＪｉａｎ－ｋａｎｇ（ＨｕａｚｈｏｎｇＵｎｉｖｅｒｓｉｔｙｏｆＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏｇ...

简介：and satellite element 1.,and the satellite element 1. a hybrid type form of  ,for the element