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简介：ＰｈｙｓｉｃａｌｂａｃｋｇｒｏｕｎｄｏｎｅｓｔｉｍａｔｉｎｇｂｖａｌｕｅＷＥＩＱＩＯＮＧＨＵＡＮＧ（黄玮琼）ＷＥＮＸＩＡＮＧＬＩ（李文香）ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｐｈｙｓｉｃｓ，ＳｔａｔｅＳｅｉｓｍｏｌｏｇｉｃａｌＢｕｒｅａｕ，Ｂｅｉｊｉｎ...

简介：Duringtherupturesofanearthquake,thestrainenergy.△E,.willbetransferredinto,atleast,threeparts,i.e..theseismicradiationenergy(E_s),fractureenergy(E_g),andfrictionalenergy(E_f),thatis,△E=E_s+E_g+E_f.Friction,whichisrepresentedbyavelocity-andstate-dependentfrictionlawbysomeresearchers,controlsthethreeparts.Oneofthemainparametersofthelawisthecharacteristicslipdisplacement.D_c.ItissignificantandnecessarytoevaluatethereliablevalueofD_cfromobservedandinvertedseismicdata.SinceD_ccontrolstheradiationefficiency.η_R=E_s/(E_s+E_g),thevalueofη_risagoodconstraintofestimatingD_c.Integratingobserveddataandinvertedresultsofsourceparametersfromrecordedseismograms.thevaluesofE_sandE_gofanearthquakecanbemeasured,thusleadingtothevalueofη_R.TheconstraintusedtoestimatethereliablevalueofD_cwillbedescribedinthiswork.AnexampleofestimatesofD_c.basedontheobservedandinvertedvaluesofsourceparametersoftheSeptember20,1999M_S7.6Chi-Chi(Ji-Ji).Taiwanregion,earthquakewillbepresented.

简介：Inordertoconstructestimatingfunctionsinsomeparametricmodels,thispaperintroducestwoclassesofinformationmatrices.Somenecessaryandsufficientconditionsfortheinformationmatricesachievingtheirupperboundsaregiven.Fortheproblemofestimatingthemedian,someoptimumestimatingfunctionsbasedontheinformationmatricesareacquired.Undersomeregularityconditions,anapproachtocarryingoutthebestbasisfunctionisintroduced.Innonlinearregressionmodels,anoptimumestimatingfunctionbasedontheinformationmatricesisobtained.Someexamplesaregiventoillustratetheresults.Finally,theconceptofoptimumestimatingfunctionandthemethodsofconstructingoptimumestimatingfunctionaredevelopedinmoregeneralstatisticalmodels.

简介：Anewmethodforestimationtheboundsofeigenvaluesispresented.InordertoshowthatthemethodproposeisaseffectiveasQiu’s,anundampingspring-masssystemwith5nodesand5degreesoffreedomisgiven.Toillustratethatthepresentmethodcanbeappliedtostructureswhichcannotbetreatedbynon-negativedecompsition,aplandframewith202nodesand357beamelementsisgiven.TheresultsshowthatthepresentmethodiseffectiveforestimatingtheboundsofeigenvaluesandismorecommonthanQiu’s.

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简介：Inthesystemofm(m≥2)seeminglyunrelatedregressions,weshowthattheGauss-Markovestimator(GME)ofanyregressioncoefficientshasuniquesimplifiedform,whichexactlyequalstotheonestepcovariance-adjustedestimatoroftheregressioncoefficients,andhenceweconcludethatforanyfinitek≥2thek-stepcovariance-adjustedestimatordegeneratestotheone-stepcovariance-adjustedestimatorandthecorrespondingtwo-stageAitkenestimatorhasexactlyonesimplifiedform.Also,theuniquesimplifiedexpressionoftheGMEisjusttheestimatorpresentedintheTheorem1ofWang’work[1988].Anewestimateofregressioncoefficientsinseeminglyunrelatedregressionsystem,ScienceinChina,SeriesA10,1033-1040].

简介：土壤的描述水力的性质对环境管理重要；然而，直接测量土壤勤劳、费时间、昂贵，这很好被认出水力的性质。这份报纸考察作为一个其他的工具过去常估计土壤的pedotransfer功能(PTF)的发展水力的性质在最后二十年期间。象察觉到的卫星imagery/remote一样的现代土壤调查技术在开发PTF被使用了。比作机械学的途径，在物理性质之间的实验关系和水力的性质为预言土壤收到了宽偏爱水力的性质。许多PTF能在文学基于不同参量的功能被发现。很多个研究人员追求了能描述土壤的所有类型的水保留特征的通用功能，但是没有单个功能能被称为通用尽管货车Genuchten(VG)功能是广泛地采用的大多数。大多数报导参量的PTF集中于获得水保留的参数弄弯的VG(WRC)的评价。很多个物理、词法、化学的性质在PTF被用作预言者变量。通常，回归算法/技术(统计/神经的回归)被用于校准PTF。然而，有利用数据采矿技术的报告，例如，模式识别和基因算法。精制过去常让刻度改进PTF的精确性和可靠性的数据是批评的，这被推断。包括根均方差(RMSE)，许多统计索引同意索引(d)，最大的绝对错误(我)，吝啬的绝对错误(MAE)，决心的系数(r2)和关联系数(r)，被不同研究人员使用了评估并且验证PTF。这被说服是地点特定，对PTF的研究兴趣将继续直到通用PTF被开发并且验证。在未来研究，改进了方法将被要求从存在数据库提取信息。

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简介：不同变化(替换)与微妙的还重要的差别当模特儿的为估计在编码蛋白质的序列之中的率采用的同义、非同义的替换的方法，它导致进化信息的不同估计。自从在指向的数据集以内的顺序变化的数量总是是无法预言的，很少注意都没为获得可靠估计被奉献给方法的比较。到我们的知识，几乎没有在关于这些不同方法的评估的文学可得到的很少信息。在这研究，我们比较了六个广泛地使用的方法并且用模仿的序列向结果提供了评估。结果显示那合并顺序特征(例如transition/transversion，偏爱和nucleotide/codon频率偏导)进方法能产出更好的性能。我们建议结论与有关或源于Ka，K分析不应该乐意地从一个方法仅仅根据结果被拉。

简介：ＥｘｐｅｃｔｅｄｍａｇｎｉｔｕｄｅａｎｄｄｉｓｔａｎｃｅｏｆｐｏｔｅｎｔｉａｌｓｏｕｒｃｅａｒｅａａｎｄｔｈｅｅｓｔｉｍａｔｉｎｇｍｅｔｈｏｄＭｅｎｇ－ＴｔａｎＧＡＯ（高孟潭）（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｐｈｙｓｉｃｓ，ＳｔａｔｅＳｅｉｓｍｏｌｏｇ...

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简介：拿估计到达的方向被介绍的进报道的在数组元素之中的相互的联合的一个multi-subarraysubspace试穿方法。一致线性数组的相互的联合矩阵与banded被建模对称的Toeplitz矩阵。根据相互的联合矩阵的DOF(自由的度)，在二个方面的数组元素的部分被忽视。精神算法的理论特征，适合算法的subspace之一，被学习。为大N和一致线性数组，MCLS精神评价错误是asymptotically，联合，与零个工具散布的Gaussian，和它的协变性表达式被获得。它从模拟被知道在那里存在当当它的变化有一些增加时，相互的联合不存在时，有为数组元素和信号来源的某些数字的最低评价错误的subarray，和它估计到达的方向的性能接近理想的状况。方法与高分辨率被用于深测术的sidescan声纳，并且好结果被获得了。以增加数组元素的数字的成本，方法能减少在数组元素之中的相互的联合的爱。

简介：Background:Capturingtheresponseofforestecosystemstointer-annualclimatevariabilityisagreatchallenge.Inthisstudy,wetestedthecapabilityofanindividual-basedforestgapmodeltodisplaycarbonfluxesatyearlyanddailytimescales.Theforestmodelwasappliedtoaspruceforesttosimulatethegrossprimaryproduction(GPP),respirationandnetecosystemexchange(NEE).Weanalyzedhowthevariabilityinclimateaffectedsimulatedcarbonfluxesatthescaleoftheforestmodel.Results:Sixyearsweresimulatedatadailytimescaleandcomparedtotheobservededdycovariance(EC)data.Ingeneral,theseasonalcycleoftheindividualcarbonfluxeswascorrectlydescribedbytheforestmodel.However,theestimatedGPPdifferedfromtheobserveddataonthedaysofextremeclimaticconditions.Twonewparameterizationsweredeveloped:oneresultingfromanumericalcalibration,andtheotherresultingfromafilteringmethod.Wesuggestnewparametervaluesandevenanewfunctionforthetemperaturelimitationofphotosynthesis.Conclusions:Theforestmodelreproducedtheobservedcarbonfluxesofaforestecosystemquitewel.Ofthethreeparameterizations,thecalibratedmodelversionperformedbest.However,thefilteringapproachshowedthatcalibratedparametervaluesdonotnecessarilycorrectlydisplaytheindividualfunctionalrelations.TheconceptofsimulatingforestdynamicsattheindividualbaseisavaluabletoolforsimulatingtheNEE,GPPandrespirationofforestecosystems.

简介：电话中心在过去的十年期间变得世界范围。调用中心管理器考虑的最重要的方面之一是它的操作符的优化，它暗示盖住高度可变的需求并且发现一个有效方法把人分到某些移动以便完成理想的服务水平和放弃率。另一挑战正在决定安装为特定的电话中心是哪个系统适当的。我们应该有一个单个技巧的电话中心或多技巧电话中心吗？如果我们确实有后者，我们应该欺骗多少多技巧代理人职员？在这案例研究，我们产生并且分析分离事件的系统模拟优化模型在实际配置下面并且在跨training的不同层次下面测试一个真实世界的调用中心的行为。模型结果帮助打电话给中心经理由：1)决定操作员的最佳的号码需要让不同职员配置以便为服务水平和放弃完成目标；2)在电话中心关于在关键大小之间的交易提供信息；并且3)关于需要并且使用了每工作时间估计要求完成性能的四小时的移动的号码的操作符的号码提供有用信息指向。我们从这案例研究的试验性的调查结果建议一个双性人技巧电话中心在与一个完整技巧或单个技巧的电话中心相比的长期间经济地更好。这案例研究由为操作管理社区提供另外的经理的卓见扩充知识的电话中心身体。

简介：Structuralfinger-jointed(FJ)lumberwasusedmainlyinstructuralapplicationsincludingglue-laminatedbeamsandwoodenI-joistsandmorerecentlyinparallelchordwoodtrusses.ThepaperevaluatedstrengthpropertiesofstructuralFJlumberbythreenondestructivemethods(edge-wisebending,longitudinalandtransversalvibration)inordertofindanalternativetotraditionalevaluationmethods.LumberwassawnfromthelogsfollowingapatterntypicallyusedinChinatomaximizethevolumeofrecover...

简介：Byusingthecenterprojectionimagesequencetoestimate3-Dmotionparameters,oneneedstoknowthecorrespondingrelationshipbetweenthefeatureofmotionobjectinspaceandtheprojectioncoordinateonimageplane.Inordertoavoidusingtherelationshipoffeaturecorrespondence,thetensoranalysismethodintheaffinetransformationsystemispresented,andthesimulationdataofexperimentalresultsaregiven.

简介：ThisisPartⅡofthisseries.ItintroducesthetechniqueforrecognizingMαCSphasedpropertiesanditsprecipitationcenterorcentersbymeansofdynamicdigitalizedcloudmapsandpresentstheassessmentoftheeffectivenessofthemodelproposedinPartⅠastoitsfittingandforecastingaccuracy.

简介：AbstractBackground:The outbreak of coronavirus disease 2019 (COVID-19) has become a pandemic causing global health problem. We provide estimates of the daily trend in the size of the epidemic in Wuhan based on detailed information of 10 940 confirmed cases outside Hubei province.Methods:In this modelling study, we first estimate the epidemic size in Wuhan from 10 January to 5 April 2020 with a newly proposed model, based on the confirmed cases outside Hubei province that left Wuhan by 23 January 2020 retrieved from official websites of provincial and municipal health commissions. Since some confirmed cases have no information on whether they visited Wuhan before, we adjust for these missing values. We then calculate the reporting rate in Wuhan from 20 January to 5 April 2020. Finally, we estimate the date when the first infected case occurred in Wuhan.Results:We estimate the number of cases that should be reported in Wuhan by 10 January 2020, as 3229 (95% confidence interval [CI]: 3139–3321) and 51 273 (95% CI: 49 844–52 734) by 5 April 2020. The reporting rate has grown rapidly from 1.5% (95% CI: 1.5–1.6%) on 20 January 2020, to 39.1% (95% CI: 38.0–40.2%) on 11 February 2020, and increased to 71.4% (95% CI: 69.4–73.4%) on 13 February 2020, and reaches 97.6% (95% CI: 94.8–100.3%) on 5 April 2020. The date of first infection is estimated as 30 November 2019.Conclusions:In the early stage of COVID-19 outbreak, the testing capacity of Wuhan was insufficient. Clinical diagnosis could be a good complement to the method of confirmation at that time. The reporting rate is very close to 100% now and there are very few cases since 17 March 2020, which might suggest that Wuhan is able to accommodate all patients and the epidemic has been controlled.