精度

The coordinate transformation and numerical integration was executed on the discretized tetrahedral elements based on which the 3-D MT vector-finite element method was implemented. A whole computation framework for 3-D vector-finite element method with unstructured mesh was given. Based on this some typical models were tested which has demonstrated that our algorithm could distinctively avoid problems caused by the fake solution and both the accuracy and efficiency were enhanced which made our algorithm has a bright future for further application.3. According to theory of Sobolev vector space and the discretization of Helmholtz space, the error estimate which was suitable for 3-D MT vector-finite element modeling was deduced by which the procedure of adaptive technique was guaranteed.4. Based on the fully unstructured tetrahedralization and optical strategy, the 3-D magnetotelluric h-adaptive vector-finite element method was presented through combining the error estimate. With this work, the accuracy and creditableness for 3-D MT complicatedly modeling was guaranteed.5. The 3-D magnetotelluric h-adaptive vector-finite element algorithm with unstructured mesh was implemented.

针对非结构化的四面体单元，采用坐标变换和数值积分方法，实现了MT三维矢量有限单元分析，建立起基于非结构化网格的三维MT矢量有限元计算流程，并对典型模型和国际标准电磁模型进行了数值模拟，结果对比和分析表明，基于非结构化网格的三维MT矢量有限元不仅消除了节点型有限元的伪解，而且具有很高的计算精度和速度，有广阔的应用前景。3、根据Sobolev函数的向量空间和Hemlholtz空间的分解，推导出基于残差的三维大地电磁矢量有限元后验误差估计公式，为三维大地电磁自适应矢量有限元数值模拟的实现奠定了基础。4、在完全非结构化四面体单元剖分及优化基础上，结合三维大地电磁矢量有限元后验误差估计公式，提出了基于非结构化网格的三维大地电磁h-型自适应矢量有限元计算策略，保证了对复杂大地电磁模型数值计算的精度和可靠性。5、实现了基于非结构化网格的三维大地电磁h-型自适应矢量有限元计算流程，对典型模型和国际标准电磁模型进行了数值模拟。

In harsh environment, the precision measurement of the axis angle is critical for the development of space system. The factors such as temperature variations and platform vibration severely limit the accuracy and life time of axis angle measurement device in space.

在复杂恶劣的气候条件下进行高精度的轴角测量已经成为发展空间应用技术的主要瓶颈，其中空间温度交变和振动环境，严重制约着空间用轴角测量装置的精度和使用寿命。

The calibration method can generate the sufficient calibration points with high accuracy for structured light system,which decrease error from image processing and cumulative computing according to invariance cross ratio.

该方法可以降低图像处理过程所引入的误差，减少多次交比不变计算标定点所带来的累积误差，得到多组高精度的标定点，从而提高结构光系统的标定精度。

At present,the moving crossrail constructure has been used on gantry CNC machine tool extensively. The reasonable construction affects the dynamic performance of the whole machine tool and parts machining accuracy .

目前，龙门式数控机床已经广泛采用了动横梁结构，该结构的合理与否直接影响整个机床的动态性能和零件的加工精度，而加工精度正是影响机床的应用范围的主要因素。

At last, the factors affecting pitch measurement accuracy of Marh891E Gear measurement center was analyzed; the hardware and the software of the ultra-precision gear total cumulative pitch error measurement device were improved, which perfected measurement system and increased the measurement efficiency and accuracy.

本文最后分析了Marh891E齿轮测量中心上、下顶尖不同轴对被测件齿距精度的影响，并通过具体分析对其进行调整；对超精密齿轮齿距累积总偏差测量装置的硬件控制部分及软件部分做了改进，完善测量系统，提高检测效率和精度。

By using this method, the angular frequency, amplitude, initial phase angle, decay constant of each component in transient voltage and/or current waveforms can be precisely extracted. Also, all other kinds of transient procedure can be analyzed by this method. Thirdly, a new definition of generalized instantaneous reactive power and generalized instantaneous reactive current in dq0 coordinates under any nonsinusoidal and unbalanced three-phase circuit is proposed for the first time. The detection and compensation method for different instantaneous reactive currents are also concerned.

本文首先提出了用于快速高精度频谱分析的一种改进快速傅立叶变换方法，该法具有速度快、精度高、抗混迭、不受采样定理约束、可以分析出谐次大于N／2的频谱系数等特点，可方便地应用于电力系统谐波分析及其它各类频谱分析；然后提出了基于非线性最小二乘优化法的电力系统暂态波形分析方法，可准确求出电力系统暂态电压、电流波形中各个分量的角频率、幅值、初相角及衰减常数，并可广泛应用于各类暂态过程波形分析。

The high precision reflector panel is part of a paraboloid of revolution. Taking the forming technique of separated manufacture, the precision of the panel edge is important as it is a curve in space.

高精度反射器面板型面为旋转抛物面的一部分，采用分块成形拼接安装的方法制造，每块面板的边缘形状为空间曲线，对边缘精度要求很高。

The interpolation algorithm of introduced error compensation for complex parametric curve in space is proposed for the high precision interpolation of parametric curve on the basis of studying the first, second order taylor expression parametric curve interpolation algorithm and the plane parametric curves interpolation algorithm.

以一、二阶泰勒展开式参数曲线插补算法和平面参数曲线插补算法研究为基础，提出引入误差补偿值的复杂空间参数曲线高精度插补算法以实现空间曲线的高精度插补。

Therefore, the primary purpose of the present study is to construct the projection methods in higher order accuracy. Furthermore, the proposed projection methods will be applied to nonstaggered grids, curvilinear coordinates, and moving mesh cases.

因此，本文从提高数值方法计算精度入手，构造了高阶时间精度的投影方法，并将投影方法推广到非交错网格和一般坐标系及动网格中。

Computer automatically cutlass, cutter machine, high-precision plotter, as well as various high-precision measuring instruments tested.

电脑自动弯刀，切刀机，高精度绘图仪，以及各种高精度检验测量仪器。

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。