参数变换

Only in cauchy distribution are expected value and variance non-exist. By sas programming with SQL and MACRO we solve the fit of frequency distributions of data with these distributions. Meanwhile good-of-fit test is actualized so that the bound of parameters of distribution function is dwindling until the desired accuracy is arrived. The process is executed by the circle of macro.

利用SAS的SQL和MACRO等语句编写了大量的程序，以拟合优度检验结果为标准，不断地变换八种分布的参数变化范围，通过宏程序的不断循环，逐步缩小参数的范围，最后达到预先设定的标准，从而可以发现八种分布中哪几种分布能比较好地拟合给定的实际频数资料，我们再根据拟合优度检验的结果判断出哪种分布拟合实际频数资料最好，最终获得该频数资料的最佳的理论分布函数形式。

At present transistor characteristic Picture device(JT-1 type)are maden wid-euse of measuring it's characteristic and parameter. But it needs user's transfer-ing and Calculating that measures triode direct current amplification factor β=It is not easy.

目前测试晶体管特性和参数，大都采用JT—1晶体管特性图示仪，它测试三极管参数直流放大系数β=，需要人工变换与计算。

Parameter identification and load identification on basis of frequency-domain are all researched very well, while the error of truncation, which is brought by data conversion, can"t be avoided. So, how to avoid these errors and identify the structure"s modal-parameter and exterior-load accurately will be the key technique of this field in the future, and some research work shall be done in time-domain.

针对模态参数辨识、动态载荷识别的频域方法较为成熟，但频域法中数据变换带来的截断误差却无法避免的现状，着重对模态参数辨识，尤其是动态载荷识别的时域方法作了一定的探讨。

This paper discussed the coordinate transformation method of WGS84 coordinate system to 1954-BeiJing Gauss grid coordinate. Introduced transformation model of WGS84 to Beijing 54 and computing method of transformation parameter. According to different model and computing method, computed and compared with the result combine real data. Think that adopt base-line vector quantity ask four parameters model have higher transformation precision.

本文详细讨论了WGS84大地坐标转换到北京54坐标系下的高斯平面坐标的方法，重点介绍了WGS84和北京54的空间直角坐标的转换模型及转换参数的计算方法，并根据不同的模型和计算方法结合实际数据进行计算和结果的比较，认为采用基线向量求解的四参数模型具有较高的转换精度，分区变换和提高控制点精度也能提高转换的精度。

As for hardware design, in signal converter, in order to improve sensitivity, the parameter of signal converter is gotten through math illation.

在硬件设计方面：为了提高灵敏度，通过数学推导设计传感器信号变换电路中的各个参数，并给出了各参数的求取公式。

Using the method of Laplace transform, the solutions of impulse loading condition and step loading condition were got.

在两种常见的排污条件下——瞬时点源和一维恒定源，运用拉普拉斯变换得到了模型的解析解；结合室内静态和动态试验，确定了模型中各参数的取值方法；并分析了几个主要参数变化对模拟结果的影响。

Firstly,to abtain the parameters of coupling system,such as the focal length and the position of the lens,computing the Gaussian lens formula,then establishing the rectangular coordinate system and constructing equation and tracing the marginal ray to compute the parameter of the radius of the image beam waist.

首先使用高斯光束的透镜变换公式计算透镜的焦距及放置位置等耦合系统的参数，然后建立直角坐标系并利用耦合系统的参数构建方程，对边缘光线追迹，计算出像方束腰半径值。

Although the Hough transform is widely used in image processing research, because it is a from the image space to parameter space of the mapping relations.

虽然Hough变换被广泛应用于图像处理的研究，但由于它是一种从图像空间到参数空间的映射关系，无法对无参数的离散的点进行提取。

By parameterizing the rotation transformation part of the orthogonal moving frame with four Euler parameters, a simplified optimization function is derived.

采用 4个欧拉参数对正交活动标架的旋转变换矩阵进行参数化，得到了一个简单的优化方程。

Mapping ordered eigenvalue points of sample covariance matrix of the observation data onto Hough parametric space,the number of eigenvalues of noises can be estimated by detecting the peak points on Hough parametric space,and thus the number of signal source is determined.

该方法通过Hough变换将观测数据的采样协方差矩阵的排序特征值点投影到Hough参数空间，通过检测Hough参数空间中积累的峰值来估计噪声特征值的数目，从而确定信源的个数。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。