计算误差

Transfer models were developed with overall wetting condition and part overall wetting and some water droplets larding in air condition. The relative errors of efficiency prediction are small than 2 percent because Lewis factor is equal to 1.The method to determine the mean saturated line slope of moist air was presented, which can apply to hot water and air. The wall wetting rate has remarkable effect on cooling efficiency. But water droplets in air effects are small and can be ignored in engineering calculations.

本文分别建立了壁面完全润湿传递模型与同时考虑空气中夹杂液滴且壁面不完全润湿条件下的板式湿式空冷器传递模型，数值计算得到传递模型应用刘易斯关系式对冷却效率的预测相对误差小于2％；提出了既适用于热流体为热水、也适用于热流体为空气的湿空气过程平均斜率的确定方法。

However, as a result of the calculation and regulation error of cutting machine, the spiral bevel gears that are produced by cutting once are difficult in attaining good contact and transmission quality. Therefore, it is necessary to simulate the transmission of real gears and then to find optimal cutter and cutting machine parameters.

但是，由于人为计算和生产、调整过程的误差，一次试切加工出的弧齿锥齿轮一般难以达到最佳的接触传动质量，因此根据现有切削参数对弧齿锥齿轮进行接触传动的仿真，从而找出较好的切齿刀盘和机床调整参数是非常必要的。

The performance of PDA-MUD is close to the optimal multi-user detector, but computational complexity of PDA-MUD is higher than the linear minimum mean-square error multi-user detector.

虽然使用机率资料连结演算法之多使用者侦测器可以得到近乎最佳化多使用者侦测器的效能，但其计算复杂度相较於最小均方误差多使用者侦测器仍然偏高。

According to verifying 11 vacuating wells parameters such as structure and sand body thickness that have been predicted by model, it shows high coincidence rate of more than 90% to real datum. Moreover, the permeability variation in pilot site accords with water flooding situation. The computed parameters such as reserves, cumulative oil production of single well and area, water cut have small relative error of less than 2%, the matching accuracy degree is high.

通过11口抽稀井检验，模型预测的构造、砂厚等参数与实际情况相比，符合率在90%以上；试验区的渗透率变化与水淹状况也具有较好的一致性；储量、区块及单井累积产油量、含水等参数计算的相对误差均小于2.0%，拟合精度高。

On the basis of the investigation of different moments, the concept of generalized moments is firstly defined and then, an abstract algorithm framework for computing the accurate generalized moments is presented. The framework replaces integrals on 2-dimensions space by summations on 1-dimension ORBIR list without introducing the error incurred by discrete sampling, and therefore, reduces the computation complexity for moments generation.

矩在工程实践中的应用非常广泛，在考察矩的实质的基础上，定义了泛化矩的概念，并研究泛化矩的生成框架，该框架在不引入离散化过程中存在的采样误差的前提下，将矩生成过程中需要的二重积分运算转化为在一维的ORBIR矩形序列上的求和，因此降低了矩生成的计算复杂度。

N algorithm for close approach determination was developed by Alfano and Negron （1993） based on polynomial splining techniques.

lfano—Negron（1993）提出的空间目标接近分析算法将最小相对距离及其对应时刻和进出误差椭球时刻的求解问题均转化为插值多项式求根问题。A—N算法在判断三次多项式根的存在性、筛选合理实根时存在缺陷，可能导致多余计算。

Natural gas ; Gas pipeline ; Orifice meter ; Measurement error ; Calculation ; Analysis

天然气；输气管道；孔板流量计；测量误差；计算；分析

As to the former, simpled multiple scattering model based on Hapke's theory is developed to improve the linearity of intimate mixture and reduce computational complexity; as to the latter, Modified Linear Mixing Model is advanced to compensate for the error in endmember spectra.

对于第一个缺陷，从Hapke理论出发，充分考虑了数据的特点，大大简化多重散射模型来提高充分混合的线形性，同时降低了原模型计算的复杂度；对于后一个问题，提出用修正线形混合模型来弥补&纯&光谱中的误差。

The sightline control strategy for bad measure precision is developed, and the control methods for vertical direction, approach direction and station keeping are presented.(2)The safe approach velocities are investigated for cuboid, sphere and cone keep out zone.(3)The design method for optimal trajectory under safety constraint is developed. The cone and cuboid keep out zone can be described using line constraint, and then optimal trajectory design can be translated to line programming problem under line constraint.(4) The design strategy of collision avoidance maneuver is discussed, and the collision avoidance scheme is analyzed for V-bar and R-bar approach.The control and trajectory safety in departure phase are investigated.

1提出了测量误差较大时平移靠拢段的视线控制策略，给出了横向、纵向和悬停的控制方法；(2)针对长方体禁区、球形禁区和锥形禁区三种禁区形式，研究了V-bar逼近和任意方向逼近的纵向安全速度计算问题；(3)提出了安全约束下的最优轨迹设计方法，将冲量和有限推力作用下的最优轨迹设计问题转化为线性规划问题，并给出了将锥形和方形安全区域约束转化为标准线性约束的公式；(4)探讨了紧急避撞机动的设计策略，分析了V-bar和R-bar接近的紧急避撞机动方案。

The thesis introduces an equal difference between an approximate value and an accurate value waY for panel point's coordinate calculation of the irregular curve by means of tangent line's approaching;illustrates it with a concrete example;and falls back on MATLAB mathematic software to draw an imitation picture of cutting tools' locus.

介绍一种用切线逼近非圆曲线节点坐标计算的等误差法，结合实例，借助M ATLAB数学软件，绘制出刀具轨迹的仿真图。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。