查询词典 error of computation

Experimental results in TiGems7.0 illustrate that this algorithm is independent of the numerical error accumulated in intersection computation, and can implement the data exchange of IGES B-rep model built by different CAD systems such as SolidWorks and Pro/E.

在TiGems7.0系统中的实验结果表明，该算法不依赖于求交运算中造成的数值误差，具有较好的鲁棒性，能够实现IGES的边界表示格式在SolidWorks，Pro/E等系统中的数据交换功能。

By using the computing method of this paper, emendation error after yaw-steering can be reduced to centesimal Hz level. Thus, precise computation of yaw-steering is successfully achieved.

利用该文提出的计算方法，采用偏航控制的多普勒中心校正误差可以达到0.01Hz量级，从而实现了偏航控制的精确计算。

The phase of optical wave can be recovered by the intensity transport equation under the paraxial approximation For the optical system with diffraction limit, it is difficult to get the boundary radical slope of phase and sample in the circular domain boundary when using the intensity transport equation to recover the phase, consequently, we reviewed an algorithm mentioned in the reference ［4］, namely, the equation, computation domain and boundary condition are changed, then the phase is reconstructed by the multigrid method and corrected at last Moreover, the experiment system is set to testify the algorithm, and the recovered phase from the intensity data detected by CCD is compared with the result from phase retrieval algorithm, it is found that the phase reconstruction error can reach 017 λ in the case of non-uniform intensity distribution, as a result, the method is suitable for the phase recovery with low wavefront sensing accuracy.

在傍轴近似条件下，可以利用光强传播方程对畸变波前进行相位恢复。对于衍射受限的光学系统，很难获得相位的边界径向斜率值作为边界条件，此外，要获得精确的圆域边界采样值也并非易事。为了克服上述困难，进一步研究了相位恢复改进方法，即改变了方程的表示形式、计算区域和边界条件，并用多重网格法进行求解获得重构相位，最后再将其修正。为了验证算法的精确性，搭建了实验系统对算法进行实验验证，将由CCD探测的光强分布进行计算得到的相位分布与相位恢复算法的结果进行比较，证明在光强分布非均匀的情况下，该方法恢复的相位均方根误差能够达到017 λ，可以适用于波前传感精度要求不是很高的相位恢复。标签自适应光学相位恢复相位修正光强传播方程 adaptive optics phase retrieval phase correction intensity transport equation

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。

The mathematical models of the delay of the GPS signal in the circumstance are put forward respectively. The computation of orbital arc of the two satellite constellations is based on two body problem and perturbations models. An algorithm based on the IRI model and thin layer model is used to simulate the ionospheric delay of the GPS signal. The error models of observation, multipath, relativity and antenna phase center bias are also researched. Under the consideration of the autocorrelation of the electronical measurements, the autoregressive model of time series is introduced into the noise models.

在信号仿真中，研究了利用二体运动和摄动法计算LEO卫星至GPS卫星星座的几何距离的问题；在信号的误差模型中，研究了电离层时延的IRI2001模型和单层投影模型；讨论了观测误差、多径效应、相对论效应和天线相位中心偏移的误差模型；结合电子测量噪声的具有自相关特性的经验，研究了观测误差的AR模型；结合实测数据分析，讨论了接收机钟差和卫星钟差的误差建模问题。

On the aspect of error compensation, the system using the geometric average sound pressure instead of the arithmetic average sound pressure to get the sound pressure of the measurement point. This method not only reduces the high frequency error in the sound intensity measurement, which compensates the finite difference approximation error, but also greatly reduces the computation of the sound pressure spectrum.

误差补偿方面，课题采用几何平均声压代替通常的算术平均声压来计算双传声器法的声场声压值，这样不仅可以有效的减少声强测量中的高频误差，对有限差分误差起到了补偿作用，而且还大大减小了声压谱计算中的计算量。

A character-codes model based pattern recognition method by using amplitude data of targets frequency response is proposed after the establishment of high frequency response equation of radar targets. The method uses the same unvariant character-codes to express the same target of different angles and uses sequential separating of regions of target's reference variables to obtain multiple coding vectors of all regions for every target. The category and pose of target can be determined after a two-staged classification processing such as coding processing of target range profile data and errors correcting processing of coded data. The two-stage classification results are used to target identification as posterior hypothesis to be tested by sufficient convincing and necessary convincing. The character-codes model based pattern recognition method is also adaptive to variation of target angles and controllable in error probability. Time-consuming and complicated iterative computation is not necessary in the train process of pattern recognition.

首先建立了雷达目标的高频频率响应方程，这种方程将目标多散射中心理论与目标局部谐振理论有机地结合起来；进而提出了目标多频响应结构成像方法，这种方法将瑞利区频率响应或谐振区频率响应曲线的不同部位用各种不同的近似方法去逼近，通过特征谱估计方法将目标的局部频响特征与宽带距离响应特征结合起来；然后提出了一种基于姿态角变化区域的序贯划分与多模匹配的特征编码识别方法，这种方法具有能适应目标姿态角的变化以及能控制识别的差错概率α等优点，在目标识别时只需要目标在少数有限个频率激励下的幅频响应数据。

In this paper, the algorithm of cumulating first then correlating is employed to reduce computation burden efficiently, at the same time the error of carrier frequency has to be taken into consideration which has negative effect on the peak value of coherent correlation function.

利用先叠加再相关的方法，可以减少相关运算的次数，但必须考虑载波误差对相关函数峰值的影响。

The precise satellites clock error estimation algorithm of navigation satellites is studied in this paper. The computation of precise satellites clock error based on the non-difference phase is realized and the results are compared with the products provided by IGS analysis centers.

研究了导航卫星精密钟差的估计算法，编程实现了基于非差载波相位的精密卫星钟差的解算，并同IGS若干分析中心提供的精密钟差产品进行了比较。

The midcourse guidance we used can reduce the amount of computation and the sensitivity of estimation error, be implemented easily and guide missile effectively.

我们所使用的中途导引方法能节省运算量且容易实现并降低对估计误差的敏感度，有效地导引飞弹。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。