精度

The quality of gear is primarily decided by its accuracy grade.

齿轮的优劣，主要取决于其精度等级，也就是说精度等级的提高是齿轮加工的核心问题，而精度提高的途径是尽可能的减少误差。

The results of agreement and accuracy test showed that the agreement index was above 0.85; the historical coincidence of the model reached 100%; the accuracy of cassava per-unit area yield model reached first grade while the accuracy of cassava planting area and total yield model was in second grade.

经拟合及精度检验，拟合指数均在0.85以上，历史符合率达100%，木薯单产模型为一级精度，木薯面积、总产模型为二级精度。

A high-order alternating direction implicit method for solving two or three dimensional heat equations is proposed. The method is fourth order in space and second order in time.

提出了数值求解二维和三维热传导方程的高精度交替方向隐式方法，其空间为四阶精度，时间为二阶精度，并通过Neumann方法证明是无条件稳定的。

Because dynamic target has a high precision and fast angular velocity, detecting its dynamic accuracy is still a problem.

研究一种检测精度动态靶标动态精度的方法，对于提高精度动态靶标的检验水平很有意义。

The result shows that the mixed boundary condition can greatly reduce the calculation area without affecting accuracy of the solution.It is followed by the higher accuracy of Dirichlet boundary condition which makes the boundary error greater when measured points is near the boundary, so we must take a sufficiently large border region.The homogeneous boundary condition has relatively large error, but the use of non-triangle poles devices makes apparent resistivity calculation error become small, because of elimination of the effect on potential difference for the infinite boundary. In inversion, in order to save computing time, homogeneous boundary conditions are often used to perform finite element forward calculation.

结果表明，混合边界条件精度最高，可大大缩小求解区域而不影响计算精度，其次是Dirichlet边界条件精度较高，但测点越靠边界误差会越大，必须取足够大的边界区域，齐次边界条件的误差比较大，但如果采用非二极装置，通过电位差计算得到的视电阻率，由于无穷远边界对电位差的影响基本消除，视电阻率计算误差与混合边界条件下的接近，在反演中，为了节省计算时间，经常使用齐次边界条件进行有限元正演。

Experimental results show that the proposed method is fast, stable and accurate, and the measuring accuracy of the modified CCD laser autocollimator is improved from 2 arcsec to ±0.25 arcsec in 0.23 s using the proposed method.

实验结果表明，该定位方法稳定性好，定位精度高且实时性强，应用该方法改进后激光CCD自准直仪的测量精度由2"提高到±0.25"，且单次测量时间小于0.23 s，可满足激光CCD自准直仪在小角度测量和瞄准跟踪等领域的高精度实时测量需求。

The estimation of additive and dominance effects through QTL analysis by onedimensional search while ignoring epistases showed similar accuracy to that by two-dimensional search by including epistases. Existence of epistases could decrease the precision for the estimation of additive and dominance effects. The estimation of genetic main effects would be biased if ignoring the interaction effects of QTL×environment . Joint analysis of multiple environments including QE interaction effects could increase the precision for the estimation of genetic main effects.

忽略上位性效应的一维搜索QTL分析对加性效应和显性效应的估计精度与包括上位性的两维搜索QTL分析对这两种效应的估计精度相差不大，上位性的存在可能会降低对这两种效应估计的精度；忽略QTL×环境互作效应会导致对遗传主效应的有偏估计，而包括QE互作效应的多环境联合分析能够提高对遗传主效应的估计精度。

Moreover, the accuracy analysis for different measurements and parameters(such as time measure error, azimuth measure error, buoys error, baseline length and sound velocity fluctuation) are given respectively. To make the best use of the observation datas, the weighted least square localization algorithm is used to improve the accuracy in bistatic sonar. The simulation results show that the positioning accuracy of this algorithm is higher than the other four algorithms, with which the positioning accuracy in stations areas and side areas can be improved effectively.

同时，通过对系统各个因素，如系统的各观测量的测量误差、站址误差、基线长度、声速波动等参数对算法性能的影响，得出了各方法定位误差的分布规律；为了充分利用双基地声纳系统的观测数据，提高系统的定位精度，采用加权最小二乘方法对系统的数据进行优化处理，仿真结果表明该方法定位精度明显高于基本方法的定位精度，能有效的改善发射站和接受站侧边区的定位精度，且定位性能受站址测量误差的影响较小。

The equation of ESCDAC is presented. Secondly, Based on this equation and the independent characteristic of observation valves, the ESR of the azimuth measurement error is presented by full - difference of the measurement equation which acts as the precision of ESCDAC.

然后以该方程为基础，根据该方程中各个观测量相互独立的特点，方位测量误差的均方根值可由测向方程的全微分求得，并将其作为电扫描恒差比幅测向的精度，由该精度公式可以看出，电扫描恒差比幅测向有很高的精度，并且在不同的角度上，其精度保持稳定。

Compared with former electronic balance, the design precision of high-precision electronic balance has been improved from 0.1~0.01g to 0.001g.

和以前的电子天平比较，高精度电子天平的精度由常见的较高精度0.1～0.01g到现在的精度0.001g。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。