查询词典 discretization error

Experiments were carried out to verify the static model. Experimental results show that the experimental curve matched well with the simulated curve, and there was certain error between them (maximal static error is 0.035 rad). The error cause was analyzed. Then the experiments were carried out to measure the dynamic performances of the side-sway joint. Experimental results show that the step response time of the joint was about 2 s steady value's tolerance zone ?

完成了侧摆关节静态特性试验，试验结果与仿真曲线基本吻合，验证了静态模型的正确性，但存在一定误差（最大静态误差为0.035 rad），分析了误差原因；对侧摆关节进行了动态特性试验，试验结果表明对于不同的期望值角度阶跃信号，侧摆关节开环阶跃响应时间大约是2 s

The complexity of bodywork decides variety of it's error. The station and primary factor which cause error is inconstant change and using correlation analysis can find out the primary factor. With an project given, the theory of correlation analysis for dimension variation of bodywork is discussed through correlation analysis and the layer structure of the bodywork,the state in which the error happened can be found out. How to use eigenva...

车体装焊的复杂性决定了误差产生的多因素性，车体制造过程中产生误差的工位和主要因素是不断变化的，采用相关性分析方法从众多的误差根源中准确地发现最主要的误差源；结合工程实践，论述了车体尺寸波动的相关性分析方法的原理，根据测量点的相关性分析和车体焊接工艺的层次结构，可准确地找到产生车体尺寸误差的工位；讨论了如何利用相关系数矩阵的特征值和相应的特征向量判断尺寸波动的模式，指出测量数据的波动主要按最大特征值所对应的特征向量方式波动，引起这种波动的原因是车体误差产生的主要原因，应重点采取措施加以控制；提出了应用计算机进行相关性分析的解决方案。

Firstly, we test that the error data are not normal distribution, and even the expectation is not zero. Then we analyze the possible type distribution of these error data. Finally, we use the stepwise method to fit the error data and obtain a function for some parameters of the SAIL model. As prior knowledge, the fitting function will be used to inverse these parameters ofthe SAIL model soon.

首先检验了误差数据不服从正态分布，甚至均值不为零；然后对误差数据可能服从的分布类型给予了解析，得到了指数分布和混合正态分布两种不同类型的可能分布；最后拟合了误差关于SAIL模型部分参数的函数表达式，以作为先验知识应用于反演之中。

Comparison of the synchronous measurement result of this receiver with that of a reference one shows the error trend is the same. The scatter plots of the horizontal error and vertical error distribution show that this measurement system is more stable and can reflect the position information exactly.

该接收机和参考接收机的同步测量结果表明，两个接收机对定位信息获取的误差趋势相同，通过接收机的水平误差散点图和时间序列垂直误差分布图可见，该测量系统较稳定，可准确地反映定位点的位置信息。

Simulation results show that in the image rotation and scale variation range resulted from the navigation system error and the measurement error of the wireless pressure altimeter, the proposed image matching algorithm can satisfy the accuracy demands of the scene aided navigation system and provide the location error-correcting information of the system.

仿真分析表明，在导航系统误差漂移所引起的图像旋转和气压高度表所引起的尺度变化范围内，该算法能满足匹配准确性的要求，并能有效给出系统的定位误差修正信息。

In the second chapter,I calculate the diffractive efficiency when there arealignment error,depth error of the step and the work was elength error,based on the theory ofthe fresnel lens.

第二部分文章在介绍菲涅耳透镜设计原理和衍射效率计算的基础上，重点分析了存在各种加工误差时候的衍射效率的计算情况。

This discretization scheme replaced the gradient magnitude with the absolute value of the difference and omitted an item of the original model. The smoothing velocity and effect are affected by these simplifications according to the analyses of this paper.

这个离散格式用差商代替梯度，并略去了原模型的一项，本文通过理论分析发现这些简化影响了平滑的速度和效果。

The constant element scheme is adopted in the discretization of BIE, anda system of linear algebraic equations is obtained.

采用常单元方案对边界积分方程进行离散化，得到了问题的线性代数方程组。

The alternating direction implicit method is used to solve discretization equation and supplement block iteration method to quickening convergence.

本文选择交替方向隐式迭代法，并补以块修正技术以促进收敛。

The basic approach of protecting people from being hurt or killed in an accident is to improve crashworthiness of vehicles. This paper starts with discussing theories and methods for vehicle passive safety design, which included experiential methods, analytic methods, multi-body dynamics methods, crash test methods and the finite element method. Emphasis will be paid to the basic FEM theories and algorithms of impact problems. Topics discussed include the governing equation, element discretization, hourglass control, time integration, material model, shell element algorithms and contact-impact algorithms. For more reliable simulation results, this paper then conducts study on how to accurately get material model parameters by combining the FEM method with experimental method, and develops relevant material test machine and parameter calculating software. Based on that, basic typical impact simulation and test validation study are conducted. On the basis of the above work, the paper studies the thin-shell structures'crashworthiness, which was affected by the following factors: spot-weld features, shell thickness, cross-section and pre-deformation. As to vehicle parts'crashworthiness, the paper conducts simulation study of designing energy-absorbing steering system and adaptive airbag system. A practical energy-absorbing steering wheel is designed as an example. In further depth research, the paper suggests several inverse quantificational methods for vehicle crashworthiness design based on the ideal crash characteristics. The above theories and methods are applied with good results through several practical vehicles' crashworthiness design and improvement.

文中对汽车碰撞安全性的设计理论和方法进行了归类和总结，其中包括经验法、解析法、多刚体动力学法、试验法以及有限元方法等；重点介绍了碰撞有限元法的基本理论和有关算法，涉及到有限元求解控制方程、单元离散、沙漏模态控制、时间积分、材料模型和应力修正、薄壳单元算法以及接触碰撞界面算法等，探讨了有限元计算中的材料模型参数获取技术，开发了相应的材料试验装置及材料模型参数反求软件，在此基础上进行了基本的碰撞仿真算例和试验对比研究；文中通过应用有限元方法研究了薄壁构件的碰撞吸能特性，指出了设计薄壁吸能构件时需要考虑的几个主要影响因素，即焊点、壁厚、横截面和预变形等；在关于车辆部件的碰撞安全性能设计中进行了吸能转向机构和自适应安全气囊的仿真研究，提出了吸能转向机构和自适应安全气囊的仿真研究方法；文中最后探讨了整车碰撞性能的设计与改进方法，提出了以理想碰撞特性为目标，采用分段加速度或者根据碰撞时间进行设计的反推设计法、部件吸能仿真优化设计法等量化设计方法，并通过综合应用文中所讨论的相关技术进行了整车碰撞性能的设计与改进实例研究，所选定的车型是大众化的普通轿车和碰撞安全性基础较差的微型面包车，研究结果表明，本文所提出的设计与改进方法是适用而有效的，具有重要的工程实用意义和价值。

It was just a normal day of school

那只是上学的普通一天

Which is a very good reference in this issue.

这是一个在这个问题上很好的参考。