误差因素

The factors affecting postfrac productivity are discussed in the paper. The grey associability ordering indicated that the postfrac productivity was lowly correlated with the permeability interpreted by the original log data and mainly influenced by porosity, then effective thickness, and then shale content and formation pressure. In light of the genetic neural network method, the productivity of gas well was predicted by use of the log data through programing and model training. The error detecting result proved that the model was reliable and a good application effectiveness was obtained.

文章对压后影响产能的因素进行了讨论，灰关联度排序表明，压后产能与原始测井解释的渗透率关联性小，而主要影响因素依次是孔隙度、有效厚度、泥质含量和地层压力；引用遗传神经网络法，编制预测程序，利用测井资料通过模型训练，对气井的产能进行预测，误差检验验证了模型的可靠性，取得了良好的应用效果。

We present some factors of model error, compare the influence with these factors.

分析了模型误差的各个因素，并比较了这些因素对测向算法性能的影响。

Compared with alcoholmeter method, its measurement results were more accurate. The alcohol content measurement results by chemical oxidation and by international density flask method were the same.

在这两个方法中，密度瓶法作为经典的分析方法，结果准确，但是，20℃的恒温条件不易控制，这就势必造成一定的分析误差；而酒精计法虽然具有操作简便快速，但由于酒精计精度较差和人为因素，导致误差较大。

Self-Organizing Fuzzy Cerebella Model Articulation Controller neural network is used to correct the nonlinear system inversion error due to modeling uncertainties and disturbances.

对由于建模误差、不确定性因素等引起的非线性系统逆误差，通过自组织模糊小脑模型关节控制器神经网络在线进行修正。

However, due to measurement, instrumental, computational, and even human errors, the measured process data always mix with noise ineluctably.

然而，由于测量误差、仪表精度、计算误差甚至是人为因素，过程测量数据通常不可避免地存在噪声。

It is pointed that the parabola method is straightforward, but the results are relatively coarse, and the catenaries method is relatively complicated, but the results are precise, which takes into account all-around factors.

结果发现：抛物线法比较简单，但计算结果比较粗略；分段悬链线法考虑因素比较全面，计算相对复杂，但结果比较精确；对于空缆线形竖向坐标值两种方法的误差为0 739%，无应力索长计算两种方法的误差仅为0 31%。

To solve this problem, it is necessary not only to consider the relationship caused by the difference of the method of projection, by that of the elements of ellipsoids and by that of the original data between the new and the old coordinates, but also to consider the observation errors caused by the two measurements.

解决这一问题必须考虑两种坐标间投影方法、椭圆体元素、起算数据等不同所引起的数学关系，而且还必须考虑到两次测量所引起的测量误差。本文所提出的数学模型确保以上所述数学关系准确，在此条件下，采用最小二乘法，使得由于地图投影等因素和测量误差所引起的新、旧坐标间的差异，一次加以处理。

Fully considered the structure and process characteristics of strip mill shape detection equipment,through plenty of field experiments and theory study,a set of error analysis model fit for strip mill shape detection equipment has been set up for the first time with combining theory of the classical mechanics and modern computer technology,which will create the right complex error compensation scheme and put it into the productive practice.

充分考虑板带轧机板形检测设备的结构与工艺特点，经过大量的现场试验与理论研究，将经典力学理论与现代计算技术有机结合，首次建立了一套适合于板带轧机板形检测设备系统误差分析模型，给出了相应的误差综合补偿方案，并将其应用到生产实践，对不同张力下检测辊的挠曲、倾斜、磨损等因素进行了综合补偿，大大降低了现场的板形封锁率，给企业取得了较大的经济效益，具有进一步推广应用的价值。

Thermal deformation error is one of the most important factors which influence the machining accuracy of machine tool.

热变形误差是影响机床加工精度的重要因素之一，通过实时热变形误差补偿可以提高数控机床加工精度。

During the process of the balanced cantilever construction, the bridge structure is influenced by various factors, such as shrinkage, creep and temperature change of concrete, construction error, survey error, and so on.

在悬臂施工过程中，桥梁结构受多种因素的影响，如混凝土的收缩、徐变、设计参数与实际数值的差异、施工误差、测量误差、温度变化等。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐