简介：D1300测距仪是瑞士威特厂80年代产品，是适合中短程距离测量的定时脉冲测距仪。此仪器的标称精度为5mm＋1ppm（根据最近获悉厂方提供的标称精度为3mm＋1ppm。测程在气象条件较好的情况下，厂方提供的数据是，单梭镜9km，11个梭镜14km。

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简介：Inthisstudy,thecombinedactionsofwavesandtidalcurrentsinestuarineandcoastalareasareconsideredanda2Dmathematicalmodelforsedimenttransportbywavesandtidalcurrentshasbeenestablishedinorthogonalcurvilinearcoordinates.Non-equilibriumtransportequationsofsuspendedloadandbedloadareusedinthemodel.Theconceptofbackgroundconcentrationisintroduced,andtheformulaofsedimenttransportcapacityoftidalcurrentsfortheOujiangRiverestuaryisobtained.TheDouGuorenformulaisemployedforthesedimenttransportcapacityofwaves.SedimenttransportcapacityintheformofmudandtheintensityofbacksiltingarecalculatedbyuseofLuoZaosen'sformula.Thecalculatedtidalstagesareingoodagreementwiththefielddata,andthecalculatedvelocitiesandflowdirectionsof46verticallinesfor8crosssectionsarealsoingoodagreementwiththemeasureddata.Onsuchabasis,simulationsofbacksiltingafterexcavationofthewaterwaywithasandbarundercomplicatedboundaryconditionsinthenavigationchannelinducedbysuspendedload,bedloadandmudbywavesandtidalcurrentsarediscussed.

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简介：系统评述了土壤微生物生物量磷的测定方法、含量、周转、C／P及其影响因素．土壤微生物生物量磷周转速度快，是植物有效磷的重要来源，但是易受外界影响，在土壤中含量变化范围比较大．熏蒸提取法是测定土壤微生物生物量磷含量最常用的方法，但是该法对于不同类型的土壤不具通用性．新鲜土样经氯仿蒸汽熏蒸24h，提取效果比较好；不同类型的土壤选择的浸提剂不同，酸性土壤宜用Bray-1提取剂，而碱性土壤宜用Olsen提取剂；转换系数K，亦需根据土壤类型进行校正．未来研究应侧重在几个方面：完善测定方法；土壤微生物生物量磷与土壤供磷能力、土壤磷素转化的关系；形态组成；土壤微生物生物量磷与土壤质量的内在关系．

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简介：Thepaperpresentsa0-Dmodelofanalluvialwatercourseschematizedintwoconnectedreaches,evolvingatthelongtime-scaleandunderthehypothesisofLocalUniformFlow.Eachreachisdefinedbyitsgeometry(constantlengthandwidth,time-changingslope)andgrain-sizecompositionofthebed,whilethesedimenttransportiscomputedusingasedimentratingcurve.Theslopeevolutionisprovidedbya0-Dmassbalanceandtheevolutionofthebedcompositioniscomputedbya0-DHiranoequation.Asystemofdifferentialequations,solvedwithapredictor-correctorscheme,isderivedandappliedtotheschematicwatercoursetosimulatethemorphologicalresponsetochanginginitialconditions,andtheevolutiontowardslong-termequilibriumconditions.Differentlyfromasingle-reach0-Dschematizationwithuniformgrain-size,besidesthesimplificationsadopted,themodelproposedheresimulatesthebehaviourofalluvialriversinaphysically-basedway,showingagrain-sizefininginthedownstreamdirectionaccompaniedbymilderslopes,andatendencytodevelopconcavelongitudinalprofiles.

简介：Inthispaper,ahorizontal2-Dnumericalmodelhasbeendevelopedtosimulateflowprocessesindikeburst.Thefinitedifferencemethodisusedincomputation.Themodelemploys2-Dflowequationsandcansimulatecomplexflowswhensupercriticalflowandsub-criticalflowexistsimultaneouslysuchashydraulicjumps.Severalsimulatedresultsareworkedouttodemonstratetheapplicabilityofthenumericalmodel,suchasfloodpropagationonadrybedofacomplexterrain.

简介：十多年来工业界一直从事时移3－D或4－D地震成像技术的分析研究，有越来越多的文章报道了这方面的成功实例。最近报道的两个成功实例研究是：位于挪威北海的Draugen地区和位于英国大陆架之上的Cannet-C地区。这两个地区在技术上取得了成功，提供了储层内部随时间推移而变化的优质图像。这些4－D结果改变了井位，并且减少了油田开发决策带来的代价高昂的风险（注意：本文的“4－D”表示时移地震成像）。本文重点阐述了4－D地震定量评价对石油经济的影响。在总结出4－D对油藏管理影响的几个方面后，便可建立经济模型来定量评价这种影响。该种决策性树状模型运用了贝叶斯定量计算4－D产生的修正概率。模型说明，即使4－D信息是不完善的，但对于钻加密井而言，还是可以大大提高开发方案的价值。

简介：Abrandnewexpertsystemforearthquakeprediction,calledESEP3.0,wassuccessfullydevelopedrecently,inwhichthefuzzytechnologyandneuralnetworkconceptionwereincorporatedandthesteeringinferencemechanismwasintroduced.Inadditiontothefunctionsofsymbolinferenceandexplanationofthefirstgenerationoftheexpertsystemandtheknowledgelearningofthesecondgeneration,ESEP3.0hasstrongerhuman-machineinteractionfunction.Itconsistsofknowledgeedition,machinelearning,steeringfuzzyinferenceengineandsynchronousexplanationsubsystems.Inthispaper,thecomponentsandthegeneraldescriptionofthesystemareintroduced.