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320 个结果
  • 简介:2005年5月XYUT1-UTC1UT1-UT1RUT1-BPM1X(JYD)Y(JYD)日MJD0.00001“0.00001”0.001ms0.001ms0.1ms0.0001“0.0001”(0hUTC)153491-572329734-59713394212.27-625.3722.4253492-578229988-59800092211.80-631.2747.8353493-590230187-5991156415.75-643.2767.7453494-599430372-6004321526.68-652.4786.2553495-605930572-601850-4427.50-658.9806.2

  • 标签: 地球自转参数 时号改正数
  • 简介:暴雨强度公式可通过给定不同的b、n参数,用最小二乘法对公式进行拟合,求解参数S、R,计算均方根误差σbn,最终将最小均方根误差所对应的b、n以及S、R确定为暴雨强度公式的参数。首先用优选法寻找b1值下整个n的取值范围内的最小均方根误差σb1,再寻找b2值下整个n的取值范围内的最小均方根误差如σb2;然后根据σb1和σb2的大小用优选法进一步确定b值的取值范围,直到达到所要求的精度。这样既不会漏掉、又能很快找到最小均方根误差%所对应的b和n值及其所拟合的S和R。

  • 标签: 暴雨强度公式 最优法 搜寻 均方根误差
  • 简介:High-qualityseismicgeometryisthekeytoobtainhigh-qualityseismicdata,andcanaffecttheaccuracyofdataprocessingandimaging.Basedontheanalysisoftherelationshipbetweenthequalityofthegeometryandthefouracquisitionparameters(thenumberoftraces,shotlinespacing,andthespaceandnumberofreceiverlines),aqualityevaluationmethodofthegeometrybasedoncomprehensivequalityfactor(CQF)isproposed,andtherelationshipbetweenthegeometryqualityandthefourparametersisgiven.WeusefielddatacollectedinanoilfieldinWesternChinawithcomplexgeology:Firstweuseawideazimuthgeometry.Then,wecalculatetherelationshipcurvebetweengeometryanddataqualitybyvaryingeachparameterwhilekeepingtherestfixed.andtheanalysisresultsaregivenbyusingtheCQFevaluationmethod.Theresultsshowthattheshot-linespacinghasthegreatesteffectonthequalityofthegeometry,andtheincreaseofthereceiverlinespacingcanappropriatelyimprovethequalityofthegeometry,andtheincreaseofthenumberofreceivingtracescanimprovethegeometryquality.Thedifferentacquisitionparametershavedifferenteffectsontheimagingqualityofshallowanddeepevents.Themodelforwardandprestackdepthmigrationareusedtogenerateprestackdepthmigrationprofileswithdifferentacquisitionparameters.Theimagingresultsareconsistentwiththeabovecalculatedresults.Accordingtothedepthofthetargetlayer,thequalityfactorevaluationmethodisappliedtoguidethedesignofthegeometryandoptimizetheacquisitionparameterstoimprovetheimagingaccuracyofseismicdata.

  • 标签: SEISMIC ACQUISITION GEOMETRY QUALITY FACTOR ACQUISITION
  • 简介:摘要:本课题研究从实际应用的角度出发,对经常遇到的无投影参数的 GNSS独立控制网做了分析探讨,利用 GSP软件的相似变换,求出原测量网的中央子午线和投影高,解决了原测网与实际测量边长误差过大的问题。利用科傻 COSA软件一点一方向约束平差功能,解决了原测网精度低、投影参数未知等引起的原测控制点与实际测量边长不符的问题,仅改动部分坐标就可以用于施工现场控制测量。

  • 标签: 投影参数 相似变换 约束平差