差

The problem of the error of calculation formula calculating the variance of grouping data within distances in statistics was put forward,and the concrete forms of correcting formula were given by the theorem of addition and the variance of even distribution.

提出统计学中的组距分组资料方差和标准差计算公式误差问题，由方差的加法定理和均匀分布方差给出分组资料方差计算和标准差计算的修正公式具体形式，并就均匀分布数列和正态分布数列组内方差平均数进行了讨论

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。

The result indicated that, DTA and DSC apparatus constants of CDR-1 dynamic differential thermal analyzer increase along with temperature increment, but influence of temperature on DTA apparatus constant is more remarkable.

采用6种标准物质测定CDR-1型差动热分析仪的差热分析法和差示扫描量热法仪器常数，结果表明：CDR-1型差动热分析仪的差热分析法和差示扫描量热法仪器常数均随温度的升高而增大，而差热分析法仪器常数受温度的影响更为显著。

The main contents of this course include: the construction, convergence, compatibility and stability of finite difference scheme of elliptic equation, parabolic equation and hyperbolic equation, the construction method and computation format of finite difference scheme of a system of partial differential equations.

本课程主要内容有：椭圆型方程的有限差分格式的构造，有限差分格式的收敛性，相容性及稳定性、抛物型方程的有限差分格式的构造，有限差分格式的收敛性，相容性及稳定性、双曲型方程的有限差分格式的构造，有限差分格式的收敛性，相容性及稳定性、偏微分方程组的有限差分格式的构造方法及有关的计算格式。

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。

Using two symmetrical plano-convex lens system to fabricate grating was analyzed and the characteristic of diffraction wavefront aberration of the grating was summarized by ray tracing program using MATLAB siftware.

分析使用两个对称的单平凸透镜光路制作光栅并用MATLAB编写光线追迹程序分析了所制作的光栅的衍射波像差的特点，经计算得出在较小焦比D/F情况下其衍射波像差仅与两支光路点光源的调节偏差之差有关与单独的各个偏差无关；初级像差中球差很小几乎可忽略：彗差仅与垂轴调节偏差之差成线性关系；像散仅与轴向调节偏差之差成正比；且当平凸透镜的焦比D/F增大时，各像差项迅速增大。

Based on residual sensitivity matrix and signs of residuals, this paper presents a new method to determine the possibility of existence of the worst residual contamination. Then a new method is presented to identify the worst residual contamination based on signs of measurement residuals.

文中基于残差符号信息研究状态估计中的残差污染问题，探讨了基于残差灵敏度矩阵和残差符号判断存在严重的残差污染的可能性，在此基础上，提出了利用残差符号信息识别严重的残差污染的方法，用简单的图示直观地描述了这一方法。

Acquired conclusion was that the sample mean value submitted to normal distribution, and the sample variance was composed of a number of linear sum of random variable submitted to Chi-Squared distr.

得出的结论是：样本均值服从正态分布，样本方差由若干个服从卡方分布的随机变量的线性之和组成；样本均值的期望等于各管落点期望的算术平均值，方差为各管方差的算术平均值；样本方差是各管落点总体平均方差的无偏估计，方差与各管落点散布的差异相关；样本均值与方差相互独立的充要条件是：各管落点属于独立同分布样本。

The Difference Amplifier 差分放大器: The difference amplifier is the complement of the summing amplifier and allows the subtraction of two voltages or, as a special case, the cancellation of a signal common to the two inputs.

电路见图5，这种电路在运算电路中相当有用，比如差分对单端的转换，抑制共模信号。

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。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失