最差
- 与 最差 相关的网络例句 [注:此内容来源于网络,仅供参考]
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And then some ellipses that AUGR estimator is better than the OLS estimator and AUGL estimator is better than the OLS estimator are given, respectively.Second, the definition of the almost unbiased unified biased estimator is proposed. This definition includes the familiar almost unbiased estimators in literatures, and it is the unified expression of the familiar almost unbiased estimators. Followed the biased and variance are compared of AUUB estimator and the unified biased estimator, respectively. AUUB estimator has smaller bias than UB estimator and the variance of AUUB estimator is between the variance of UB estimator and 4 times of the variance of UB estimator. Finally the properties of AUUB estimator are discussed. The conclusion is gained that there are parameters made AUUB estimator is better than OLS estimator in terms of their mean square error. The sufficient and necessary condition that AUUB estimator is admissible is given. The ellipse is given that AUUB estimator is
然后给出了几乎无偏统一有偏估计的定义,该定义包括了文献中常见的几乎无偏估计,实现了常见几乎无偏估计的统一表达式;接下来我们比较了几乎无偏统一有偏估计与统一有偏估计的偏度与方差,得出了几乎无偏统一有偏估计比统一有偏估计有较小的偏度,几乎无偏统一有偏估计的方差介于统一有偏估计的方差与统一有偏估计的方差的四倍之间的结论;最后我们对统一有偏估计的主要性质作了讨论,证明了存在参数K,S使得几乎无偏统一有偏估计在均方误差意义下优于最小二乘估计的结论,给出了几乎无偏统一有偏估计为可容许估计的充要条件,还给出了在均方误差阵意义下几乎无偏统一有偏估计优于最小二乘估计的椭球。
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The results showed that:(1) we can mapping quantitative trait locus while estimating the variance component of QTL;(2) granddaughter design is better than daughter design when mapping QTL;(3) it is easy to map a QTL for trait with a high heriability and a large QTL variance contribution;(4) we can estimate the variance component of a QTL by TM-BLUP based on ML method whether the QTL has only 2 alleles or QTL has normal distributed alleles effects;(5) the estimation accuracy of variance component contributed by QTL was improved by using of grand daughter design;(6) the higher the heritability and the QTL variance contribution was, the more accurate estimation of QTL variance component.
结果表明:(1)采用随机QTL效应模型和最大似然法,在估计QTL方差组分的同时,能够定位QTL;(2)孙女设计与女儿设计相比,在其它因素相同时,容易检出QTL;(3)遗传力高,QTL方差贡献较大的性状,QTL检出的效果优于遗传力低,QTL方差贡献较小的性状;(4)无论QTL上有2个等位基因,还是QTL上等位基因的效应服从正态分布,都可将其看作随机效应,采用基于TM-BLUP的ML法,估计其方差组分和定位QTL;(5)QTL方差组分估计的准确性,孙女设计高于女儿设计;(6)遗传力高的性状,QTL方差贡献大的QTL,QTL方差组分估计的准确性高。
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Studied present measuring methods" advantages and disadvantages, and presented the necessity and importance of researching propellant transient heat transfer.2.according to 130 and aeronautic 90 rocket projectiles" structure, analysed and acquired physical and mathematical models for propellant transient heat transfer, also designed propellant temperature field simulation units for test.3.acquired discrete transient heat balance equation and temperature calculation program, and gave contrasting curves between experimental temperature values and program calculating temperature values as well as maximum errors and average square root errors between them.4.by programs based on the first class boundary condition, worked out temperature distribution in propellant temperature field simulation units at different time, analysed temperature field distribution law and main elements affecting heat transfer, acquired propellant mass weighted average temperature and one at the half position of propellant maximum thickness as well as maximum errors and average square root errors between them.5.established transient heat transfer mathematical model and temperature calculation program for the third class boundary condition, drew contrasting curves between temperature experimental values and calculation values and gave maximum errors and average square root errors between them, got temperature distribution in the simulation unit at different time and main elements affecting heat conduction, figured out propellant mass weighted average temperature and one at the half position of propellant maximum thickness as well as maximum errors and average square root errors between them.
分析了现有测试方法的优缺点,提出了研究推进剂瞬态导热的必要性和重要性。 2。根据130和航90两种火箭弹的结构,分析得到了推进剂传热的物理模型和数学模型,设计了推进剂温度场模拟实验装置。 3。得到了离散形式的瞬态热平衡方程和温度场计算程序,给出了实验温度与程序计算温度值的对比曲线及其最大偏差与均方差。 4。利用程序求出了第一类边界条件下、不同时刻推进剂温度场模拟装置中的温度分布,分析了温度场的分布规律和影响传热的主要因素,求出了推进剂质量加权平均温度和最大肉厚1/2处的温度时间曲线并给出了两者之间的最大偏差与均方差。 5。建立了第三类边界条件下的瞬态导热数学模型和温度计算程序,求出了温度实测值与计算值的对比曲线并给出了两者之间的最大偏差与均方差,得到了不同时刻温度场模拟装置的温度分布与影响导热的主要因素,求出了推进剂质量加权平均温度和最大肉厚1/2处温度及两者之间的最大偏差与均方差,讨论并确定了能代表130和航90推进剂温度的特征点的位置。
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In order to reduce calculation error, the frequency distribution of average values is used to compute the mixed distribution's digital features of each component distribution, thereinto, the number of the component distribution is determined by AIC, choose the number that meets the minimum value of AIC as the component number of mixed distribution, and the other parameters are estimated by EM algorithm; Secondly, because each component distribution is corresponding to a kind of major gene genotype, according to the values of the average and variance of the each component distribution, we can use the limit error of the normal distribution to plot each individual into the correspondent component distribution, namely into correspondent major gene genotype. Then we regard each major gene genotype as a treatment level of one-way analysis of variances, and the one-way multivariate analysis of variance is carried out to calculate the covariance matrix of major gene effect, covariance matrix of polygene effect, covariance matrix of environment effect and so on; At last, combining the weights of the each component distribution of mixed distribution, we can calculate the variance of major gene effect, the variance of polygene effect, environmental variance and the genetic gain of the quantitative trait.
为减小计算误差,本研究采用均值的频数分布来计算各成分分布的数字特征,其中成分分布个数根据AIC准则,选择使AIC值达到最小的成分分布个数作为混合分布的成分分布数,分布中其它参数的确定利用EM算法来估计;其次,每个成分分布对应一种主基因基因型,根据各个成分分布的均值和方差,利用正态分布的极限误差将每个个体划分到相应的成分分布中,即相应的主基因基因型中,将每种主基因型作为单因素方差分析的一个处理水平,对其进行单因素的多元方差分析,分别计算主基因效应协方差阵、多基因效应协方差阵、环境协方差阵等参数;最后结合混合分布中各成分分布的权重即各主基因基因型的分离比例,计算主基因效应方差,多基因效应方差和环境方差,以及遗传力等参数,进而计算该数量性状的遗传进展。
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Assuming all samples coming from populations with the same standard deviation σ, the accuracy of estimating σ from observations of different parts influences control limits of target control chart. The dissertation points out shortcoming of traditional standard deviation estimates and proposes a unbiased estimate of σ which results in that the variation of the estimate is minimums and the control limits is set more reliably.
假设不同工件的样本标准方差均来自于同一分布,则以不同工件的样本标准方差对母体标准方差的估计的精确性直接影响了目标控制图控制界限计算的可靠性,本文分析了目标控制图传统的两种母体方差估计方法的合理性或稳健性较差的特点,给出了一种对σ无偏估计的优良方法,从而使这一方差估计量〓的散差最小,则依此最小方差的无偏估计量所得到的控制界限更为精确,更为可靠。
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Every treatment combination has 4 replications.(1)The germination indexes of the former are higher than that of the latter; the germination of the former is stimulated by NaCl density of 0.3 %, while that of the later is restrained by all kinds of NaCl density.(2)With increasing of temperature and PEG indesity,the order of germination rate and vigor of Bromus stamineus and Bromus inermis is decreaced.(3)Under treatment of broadcast sowing and plant density of 549kermels·m~(-2), Bromus stamineus has the highest bud rate, fresh weight, seed yield, while treated with 25cm row spacing and 412kermels·m~(-2) plant densities, tillers, plant height, growth rate increased to the top;(4) Under treatment of broadcast sowing and plant density of 549kermels·m~(-2), its growth rate is took second place, while treated with 15cm row spacing and 824kermels·m~(-2) plant densities, it has the highest seed yield
3撒播时,引进种在播种密度为549粒·m~(-2)处理下单位面积出苗率最高,分蘖数最多,鲜重最大,单株最高,种子产量最大;生长速度在播种密度为412粒·m~(-2)处理下生长最快,密度为549粒·m~(-2)处理下稍次之,结合方差分析可以初步确定它在撒播时的播种密度为549粒·m~(-2);(4)条播时,在行距为25cm、播种密度为412粒·m~(-2)处理下单位面积分蘖数最多,鲜重最大,单株最高,生长速度最快;种子产量在行距为15cm、播种密度为824粒·m~(-2)处理下最大,在行距为25cm、密度412粒·m~(-2)处理下次之;结合方差分析,就3种规格的行距来说,引进美国无芒雀麦条播时的行距为25cm,播种密度为412粒·m~(-2);就这两种播种方式来说,应该选择撒播。
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By the modem time series analysis method, based on the ARMA innovation model, under the linear minimum variance optimal information fusion criterion, three distributed fusion steady-state optimal Kalman filters, predictors and smoothers weighted by matrices, scalars, and diagonal matrices are presented for multisensor systems with correlated input and observation noises, and with correlated observation noises. The Lyapunov equations and formulas of computing local filtering, predicting and smoothing error variances and covariances are given, which are applied to compute optimal weights. The corresponding three distributed fusion Wiener state estimators are also presented.
应用现代时间序列分析方法,基于自回归滑动平均新息模型,在线性最小方差最优信息融合准则下,对于带相关输入噪声和观测噪声和带相关的观测噪声的多传感器系统,提出了按矩阵加权、按标量加权和按对角阵加权的三种分布式融合稳态Kalman滤波器、预报器和平滑器,其中提出了局部滤波、预报和平滑估值误差方差阵和协方差阵的Lyapunov方程和计算公式,它们被用于计算最优加权,也提出了相应的三种分布式融合Wiener状念估值器。
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This has been the Dow's worst week ever.
这是道琼斯指数历史上最差的一周。
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Ha^(-1) treatments had the least amount of grass, followed by ETH 7.6 kg a.i.
ha^(-1)处理后减少割草量效果最佳,最差是ETH 7.6kg a.i。
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If we only look at the records of teams that truly belonged among the best in the country because they had earned the right to be there on the pitch, then Hertha are, so far, the worst we've ever seen.
我们只能看球队真正跻身于全国最佳所属的记录,因为他们已经获得的权利,在球场上,则在柏林赫塔是,到目前为止,我们所见过的最差的。
- 推荐网络例句
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However, as the name(read-only memory)implies, CD disks cannot be written onorchanged in any way.
然而,正如其名字所指出的那样,CD盘不能写,也不能用任何方式改变其内容。
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Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.
镀锌钢托盘多用于出口,替代木托盘,免薰蒸,符合欧盟、北美各国对出口货物包装材料的法令要求;喷涂钢托盘适用于重载上货架之用,托盘表面根据需要制作成平板状、波纹状及间隔形式,满足不同的使用要求。
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A single payment file can be uploaded from an ERP system to effect all pan-China RMB payments and overseas payments in all currencies.
付款指令文件可从您的 ERP 系统上传到我们的电子银行系统来只是国内及对海外各种币种付款。