简介：Deepwatersedimentsarepronetolosscirculationindrillingduetoalowoverburdengradient.Howtopredictthemagnitudeofleak-offpressuremoreaccuratelyisanimportantissueintheprotectionofdrillingsafetyandthereductionofdrillingcostindeepwater.Startingfromthemechanicalpropertiesofashallowformationandbasedonthebasictheoryofrock-soilmechanics,thestressdistributionaroundaboreholewasanalyzed.Itwasfoundthattherockorsoilonaboreholeisintheplasticyieldstatebeforetheeffectivetensilestressisgenerated,andtheeffectivetangentialandverticalstressesincreaseasthedrillingfluiddensityincreases;thus,tensilefailurewillnotoccurontheboreholewall.Basedontheresultsofstresscalculation,twomechanismsandleak-offpressurepredictionmodelsforshallowsedimentsindeepwaterdrillingwereputforward,andthecalculatedvaluesofthesemodelswerecomparedwiththemeasuredvalueofshallowleak-offpressureinactualdrilling.TheresultsshowthattheMHPS(minimumhorizontalprinciplestress)modelandtheFIF(fracturinginformation)modelcanpredictthelowerandupperlimitsofleak-offpressure.ThePLC(permeablelostcirculation)modelcancomprehensivelyanalyzethefactorsinfluencingpermeableleakageandprovideatheoreticalbasisforleak-offpreventionandpluggingindeepwaterdrilling.

简介：Theresearchofpropagationcharacteristicsofair-to-watersoundtransmissionisofgreatimportancetothedetectionofaerialtargetsfromunderwater.Inordertostudythepropagationcharacteristicsofair-to-watersoundtransmissioninshallowwater,StateKeyLaboratoryofAcoustics,InstituteofAcoustics,conductedanexperimentintheSouthChinaSeainMarch,2013.Duringtheexperiment,multi-frequencysignalstransmittedbyahooterhungonaresearchshipwerereceivedbyanunderwaterhydrophone,andthedistancebetweenthehooterandthehydrophonewasfrom2.4kmto9.8kmapproximately.Throughanalyzingexperimentaldatainthiswork,theexperimentalair-to-watertransmissionlossatfrequencies128Hzand256Hzisestimatedupto9.8kminrange,anditsoscillationstructureisevident.Thewave-numberintegrationapproachisusedtosimulatetheoreticalair-to-watertransmissionlosses,whichareingoodagreementwithexperimentalvaluesandtoexplaintheexperimentalair-to-watersoundtransmissioncharacteristics.

简介：fig. 4(a) water surface elevation for a circular dam-break circular dam-break,fig. 3(a) water surface elevation for a rectangular dam-break  ,fig. 4(c) velocity field for a circular dam-break

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简介：Thetime-domainElectroMagnetic(EM)scatteringbyburiedobjectsindispersivemediaiscalculatedwithFD-TDmethod.TheFD-TDformulainDebyedispersivemedia(boththecomplexpermeabilityandthecomplexpermittivityaredescribedbyDebyeequations)arededuced,andtheabsorbingboundaryconditionisgiven.ThevalidityofFD-TDmethodinlossymediaisverifiedthroughcomparingtheFD-TD’sresultsandtheotherones.Thepropagationoftransientpulsesindispersivemediaisstudiedindetail.Thescatteringpulsesandthewiggletracesfortypicalburiedobjectsaregiven.

简介：Background:WecomparetheclimatesensitivityofEuropeanbeech(FagussylvaticaL)intwoforestnaturereservesinnortheasternGermany.Theonereserve,Schlossberg,ischaracterizedbyshallowchalksoils,whereasintheotherreserve,Eldena,soilsaredeeperandmoredeveloped.Littleisknownaboutthedroughtsensitivityofbeechonshallowchalksoils.Methods:Wecollectedincrementcoresatbothresearchsitesandestablishedclimate-growthrelationships.Intertreevariabilitywasassessedbyemployinglinearmixed-effectmodels.Results:WeexpectedtofinddistinctivelyhigherdroughtsensitivityatSchlossbergduetolimitedwateravailability,butfindonlymarginaldifferencesingrowthresponses.Atbothsites,droughtisthemajorclimaticfactordrivingtreegrowth.Adaptationsintreearchitectureandanunderestimationofthewaterholdingcapacityofshallowchalksoilsarediscussedaspossiblereasonsfornotfindingmoredistinctclimateresponses.Inanalyzingclimate-growthrelationships,wespecificallyfocusedongrowthresponsesofindividualtreesbutobservedonlylowinter-treevariabilityatbothsites.Evidentisashiftinclimateresponsepatternsfromthefirsttothesecondhalfofthetwentiethcenturywithprevious-yeardroughtconditionsbecomingmoreimportantthancurrent-yeardrought.Thisshiftisdiscussedinrelationtoawarmingtrendoverthatsameperiod,aswellaspossibletrendsinmastingbehaviorofbeech.Conclusion:Theinvestigatedbeechtreesontheshallowchalksoilareonlyslightlymoredroughtsensitivethanbeechtreesonthereferencesitewithdeeperandmoredevelopedsoils.

简介：MuchattentionshouldbepaidtoalargeFPSOmooredpermanentlyinanoilfieldwithwaterdepthofonlyabout20m,sinceshallowwatereffectsonthehydrodynamicsmaybringaboutcollisionanddamage.A160kDWTFPSOwithapermanentsoftyokemooringsystemisinvestigatedwithvariousshallowwaterdepthsandfocusesarethelowfrequencysurgemotionandmooringload.ComputationfortheFPSOsystemismadebasedonlinear3-Dpotentialfluidtheoryandtime-domainnumericalsimulationmethod.CorrespondingmodeltestiscarriedoutintheoceanengineeringbasinofShanghaiJiaoTongUniversity.Itisshownthat,inthesurgenaturalperiod,lowfrequencysurgemotionandmooringforceincreaseremarkablywiththedecreaseofwaterdepth.Especially,thesmallertheratioofwaterdepthanddraughtis,thequickertheincreaseis.Theshallowwatereffectsshouldbetakenintoaccountcarefullyfordeterminingthedesignloadofasinglepointmooringsystem.

简介：目的：察浅刺多针法与常规针刺法治疗单纯性肥胖症的临床疗效。方法：本按照循证医学的原则，40例单纯性肥胖患者随机分为浅刺多针法治疗组20例，常规针刺法治疗组20例。治疗每目1次，20次为观察疗程，在治疗前后分别记录体重、标准体重、体重指数、脂肪百分率、胸围、腰围、臀围，对所得相关资料进行分析。结果：两组经20次治疗体重、腰围等均有明显改变，两组疗效比较，浅刺多针法治疗组明显优于常规针刺法治疗组（P〈0．05）。结论：刺多针法对单纯性肥胖有较好的临床疗效，其效果优于常规针刺组。

简介：Proceedingfromtheeigenvalueequationofthenormalmodeinhomogeneousshallowwater,wederiveseveralformulaecalculatingthemodeattenuationandgroupvelocity,andcomparetheiraccu-racybymeansofnumericalresults.Thepaperespeciallydiscussestheattenuationandthegroupve-locityofcriticalmodeinaPekerischannelandshowsthatingeneral,theattenuationandthegroupvelocityofthecriticalmoderespectivelyarelessthantheabsorptionandthesoundspeedinthebot-tom.Therefore.theKornhauser,Raney,WestonTindle‘sconclusionsaremodifiedthattheattenuationandthegroupvelocityofthecriticalmodeareexactlyequaltotheabsorptionandthesoundspeedinthebottom,respectively.

简介：回响在浅水里是重要的并且在OBC系列生产明显的槽口。它也降级节和增加的质量处理和解释的困难。这篇文章介绍在槽口之间的关系，射击基于地震卷绕旋转模型的深度，和海床深度。前面的建模基于波浪方程理论被用来验证这种关系。双传感器的求和被使用压制接收装置方面multiples并且基于OBC技术的详细分析根据对下面去的波浪地的地震检波器和水中听音器的相反的反应移开槽口。在实际应用获得的好结果揭示这个方法的有效性。

简介：Whenabodynavigateswithcavityinshallowwater,bothflexiblefreesurfaceandrigidbottomwallwillproducegreatinfluencesonthecavityshapeandhydrodynamicperformances,andfurtheraffectthemotionattitudeandstabilityofthebody.Inthepresentwork,characteristicsofthenaturalcavitatingflowarounda2-Dsymmetricalwedgeinshallowwaterwereinvestigatedandtheinfluencesoftwotypeboundariesontheflowpatternwereanalyzed.TheVolumeOfFluid(VOF)multiphaseflowmethodwhichissuitableforfreesurfaceproblemswasutilized,coupledwithanaturalcavitationmodeltodealwiththemass-transferprocessbetweenliquidandvaporphases.Withintherangeofthecavitationnumberforcomputation(0.07-1.81),thecavityconfigurationswouldbedividedintothreetypes,viz.,stabletype,transitiontypeandwake-vortextype.Inthisarticle,theshapesofthefreesurfaceandthecavitysurface,andthehydrodynamicperformanceofthewedgewerediscussedundertheconditionsofrelativelysmallcavitationnumber(<0.256).Thepresentnumericalcavitylengthsgenerallyaccordwithexperimentaldata.Whenthecavitationnumberwasdecreased,thecavitywasfoundtobecomelongerandthicker,andthescopeofthedeformationofthefreesurfacealsograduallyextends.Thefreesurfaceandtheuppercavitysurfacecorrespondfairlytotheirshapes.However,thelowersideofthecavitysurfacewasratherleveledduetotheinfluenceofwallboundary.Theliftanddragcoefficientsofthis2-Dwedgebasicallykeeplinearrelationswiththenaturalcavitationnumbersmallerthan0.157,whereasdirectproportionfordragandinverseproportionforlift.

简介：Inpastterroristattacks,vehicleborneimprovisedexplosivedevices(VBIED)havebeentheprimarymannerofattackingbuildingsandinfrastructures.Preventingunauthorizedvehiclesfromapproachingaprotectedareawithanti-ramsystemswouldmaintainanestablishedstandoffdistanceagainstmovingandstationaryvehiclesandconsequentlyreduceblastanddebristhreats.Thisstrategyhasbeenconsideredthefirstlineofdefenceagainstterrorists.Severaltypesofanti-ramdeviceshavebeendevelopedinaccordancewithU.S.DepartmentofStateK-ratingcriteria,forexample,wedgebarriers,risingbeams,sliding/swinggates,anddroparms.However,thesedevicestypicallyneedadeepfoundationforinstallationandcan'tbeimplementedintomanylocationswhereadepthofexcavationislimitedinordertoprotectutilitylinesofbuildingsandinfrastructures.Thispaperpresentsarecentdevelopmentofaseriesofshallowfootinganti-rambollardsystems(SFABS)thatcansatisfyK-12ratingwithonlyfive-inchthickfooting.Ahigh-fidelityphysicsbasedfiniteelementtechniquewithavehiclecrashmodelisusedforpredictinganti-ramcapacityanddeterminingdesignparametersoftheSFABS.Full-scalevehiclecrashtestsofthedevelopedSFABSsystemshavebeencarriedouttovalidatethedesignandanalysis.

简介：平均深度的流动污染物质联合了的A2D模型基于空铅树网孔被建立精确地在这篇论文与不规则的自然边界在水区域模仿流动。格子被递归的分关于播种点产生。一个发现newneighbor算法被介绍。管理方程是在由越过在房间之间的接口使用有限的卷方法，和质量，动量和污染物质的正常流动的并置的保守变量的discretized被一个Godunov类型流动DifferenceSplitting(FDS)计划计算。模型被使用在一条腹股沟附近模仿流动地。计算的值与观察数据一致。结果显示空铅树网孔有好本地分辨率，高效率和容易的本地精炼。当适用于复杂流动领域时，空铅树格子模型能在效率提供获得，是清楚的或强壮砍流动。最后，模型在江苏HaizhouBay被用于流动地和集中地模拟。模仿的弄脏的区域与观察被匹配很好。因此，这个模型能被用来与不规则的自然土地边界预言实际的水区域的流动和集中地。

简介：为浅水里的单个模式的靠近环的刺激的一个最佳的算法被介绍。由分析草地函数矩阵的评价价值的协变性，一个最佳的来源数组重量矩阵被介绍估计草地工作矩阵。重量矩阵是一个单一的矩阵，并且矩阵元素的绝对值是相等的。基于重量，矩阵使刺激单个模式以最大的速度收敛并且稳定的算法。算法的优点被数字模拟证实。最后，浅水实验的结果被介绍，并且单个模式的精力比率比97%高。

简介：Shallowwaterflow（SWF）,adisastrousgeohazardinthecontinentalmargin,hasthreateneddeepwaterdrillingoperations.Underoverpressureconditions,continualflowdeliveringunconsolidatedsandsupwardintheshallowlayerbelowtheseafloormaycauselargeandlong-lastinguncontrolledflows;theseflowsmayleadtocontrolproblemsandcausewelldamageandfoundationfailure.Eruptionsfromover-pressuredsandsmayresultinseafloorcraters,mounds,andcracks.Detailedstudiesof2D/3DseismicdatafromaslopebasinoftheSouthChinaSea（SCS）indicatedthepotentialpresenceofSWF.Itiscommonlycharacterizedbylowerelasticimpedance,ahigherVp/Vsratio,andahigherPoisson＇sratiothanthatforthesurroundingsediments.AnalysisofgeologicaldataindicatedtheSWFzoneoriginatedfromadeepwaterchannelsystemwithgasbearingover-pressuredfluidflowandahighsedimentationrate.WeproposedafluidflowmodelforSWFthatclearlyidentifiesitsstressandpressurechanges.TheruptureofpreviousSWFzonescausedthefluidflowthatoccurredintheBaiyunSagofthenorthernSCS.

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简介：Green-Naghdi(G-N)理论是为水波浪的一个充分非线性的理论。一些研究人员把它称为一个充分非线性的Boussinesq模型。G-N理论的复杂性的不同的度被在哪儿的鈥渓evels鈥?区分越高水平，越多复杂并且大概更精确理论。在这里介绍的研究，比较在G-N理论的二个不同层次之间被做，明确地铺平II并且铺平IIIG-N限制理论。限制理论被给的水平IIIG-N的一个线性分析解决方案。一个平面沙滩上的波浪和变浅的波浪两个都与这二个G-N理论被模仿。水平IIIG-N也限制了理论罐头，这第一次被显示出被用来在浅水里预言液体速度。水平IIIG-N限制了理论被推荐而不是水平IIG-N限制理论当模仿时，充分非线性的浅水飘动。关键词Green-Naghdi理论-Boussinesq模型-充分非线性的水飘动-变浅的波浪基础条款：在资助号码50779008和111工程(B07019)下面由中国的国家自然科学基础支持了。箱箱赵在1984出生了。他是一会儿在哈尔滨工程的液体力学的一个博士候选人大学。他的当前的研究兴趣基于BEM包括Green-Naghdi理论和非线性的波浪身体相互作用。Wen-yangDuan在1967出生了。他在设计大学的哈尔滨是一个教授和一个博士监督人。他的当前的研究兴趣包括非线性的波浪身体相互作用，SPH方法和Boussinesq模型。

简介：在我们进一步探索并且适用的这篇论文，我们的最近的反散开的流动改正了有限差别WENO策划让能量守恒定律与污染物质繁殖计算浅水方程的theSaint-Venant系统的高顺序，它被一个运输方程描述。动机是高度命令当在答案的光滑的区域为近似把高顺序作为精确性时，为能量守恒定律的反散开的WENO计划生产接触断绝的锋利的分辨率。到有污染物质的运输的浅水方程的Saint-Venant系统的theanti散开的高顺序WENO计划的应用程序完成高分辨率

简介：浅水里的matchedfield处理的时间的关联(MFP)上的线性、独居的内部波浪的效果数字地与不同频率为声学的来源被调查，深度基于从experiment.It的海洋学的数据被显示出MFP的时间的关联作为独居的内部波浪的振幅减少或线性内部波浪increases.For的平均精力密度有更低的频率的声学的来源或下面定位了thermocline，tempor

简介：在华南海(SCS)的浅南方的翻发行量(MOC)的低频率的可变性为19002010的时期用一个简单海洋数据吸收(苏打)产品被调查。一个动态分解方法在MOC在哪个被分解成Ekman被使用，外部模式，并且垂直砍部件。结果证明所有三个动态部件在SCS贡献季节、年度的吝啬的浅MOC的形成。在SCS的浅MOC由二个房间组成：一顺时针方向在南方的房间和在北方的一个逆时针方向的房间；前者被Ekman流动控制，后者被外部barotropic流动统治，与贡献垂直砍是减少两个房间的大小。另外，在南方的MOC的力量被发现在过去的世纪有一个掉落的趋势，主要对一变弱减少外部部件的运输的吕宋岛海峡运输(LST)到期。进一步的分析建议变弱LST是仔细与一在赤道的太平洋上变弱西的风异例有关，它导致向北赤道的水流(NEC)分叉并且这样的向南方的移动吕宋岛的自台湾东面的菲律宾海流向日本的暖流东方的更强壮的运输。