查询词典 integration by parts

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。

Secondly,the one-step and multistep methods of the precise integration algorithms arederived by means of the integration of functional matrix by parts and interpolation function,and some recursion schemes suitable for precise integration are obtained.

然后，以函数矩阵的分部积分法和插值函数为工具，推导出精细积分的单步法和多步法，给出了多种精细积分的递推格式。

In the method,thematrix exponential is calculated precisely by using 2N algorithm and the integration offunctional matrix by parts is applied.

首先依据常微分方程的经典理论，运用指数矩阵的2N类精细算法及函数矩阵的分部积分法建立数值求解常微分方程的一般方法。

According to the indefinite integration by parts

根据不定积分的分部积分法，有

Nabla operators applied on the scalar Green's function are applied on electric and magnetic fields using integration by parts.

利用分部积分将作用在标量Green函数上的Nabla算子转移到电磁场强上。

In the union mathematical analysis the integration by parts this content two different teaching methods, we elaborate in the problem solution teaching has prohibited become the problem solution teaching class in the problem explanation introduction class.

结合数学分析中分部积分法这一内容的两种不同的教学方法，论述了在问题解决教学中切忌把问题解决教学课上成问题解答介绍课。

Then du=2xdx, dv=cosxdxBy applying integration by parts, we have

对上述方程的两边分别求导，我们可得到

The thesis will introduce, respectively, relevant concepts of residue theorem and its promotion and application in two parts In the basic concepts of chapter II, the definition, classification and relationship between function zero and pole of the isolated singular point are given to lead out relevant definition, theorem and solving method, while the core content of this paper is promotion and application of residue theorem, including calculation of integration by using residues, application in diagonal theorem and argument theorem, application in electromagnetism and theorem promotion and relevant application of extension theorems

本文将从两大部分分别引入和浅析了留数定理的相关概念及其推广和应用在第二章的基本概念部分中，给出了孤立奇点的定义和分类、函数零点与极点的关系，从而引出留数定理的相关定义与定理及其求法而本文的核心内容也就是留数定理的推广和应用，包括运用留数来计算积分、体现在对角定理与辐角定理中的应用、在电磁学中的应用及其定理的推广和推广定理的相关应用

Studies the influence of SSB_and _fin appendage on resistance of WPC by the model resistance test and flow visualization techniques,points out that the total resistance of WPC can be remarkedly reduced by improving the profile of the parts connecting SSB to ship hull and fins to SSB,and concludes that the layout of integration and profile of connection of SSB_and_fins appendage have their effects on the resistance of WPC.

对SSB加鳍组合附体对穿浪船阻力性能影响进行了初步探讨。目的是想法尽量减小组合附体的阻力增加。通过流动观察及阻力试验分析，对组合附体与穿浪船片体连接处线型提出了改进措施，使总阻力有明显的降低。研究表明SSB加鳍组合附体与穿浪船片体之间的综合布局及线型选择对阻力的显著影响。

Chapter 9 is conclusion and future prospect. There are five innovative findings in the paper. Firstly, the evolvement of extensions and connotations of two reengineering styles is analyzed based on their high risk, and finding their trends of amalgamation. With this, the concept of corporation reengineering is then redefined combining core competence theory and ideas of process change management, and decompounding it into two parts: pre-reengineering and post-reengineering. Its inner relationships are analyzed and explained by economics theory. Secondly, establishing a analysis framework of reengineering risks, risk factors of foreign BPR are analyzed and concluded systematically for the first time. Reengineering risks are divided into three parts: plan, design and executive based on process and project management, then risk factors system is abstracted. Thirdly, 72 reengineering corporations in Jiangsu province are investigated on risk condition. Furthermore, risk factors in every part are analyzed and reduced experimentally by factor analysis method, and a risk factors system to suit Chinese corporation's reengineering is established. Fourthly, setting up a choice model of reengineering projects, the objective optimization model is presented to ascertain the weigh of each factor, a method of sequencing reengineering projects is presented so that risk of each reengineering project can be evaluated and compared effectively. Fifthly, an integration relationship model among IT, BPR and strategy is established aiming at productivity paradox derivative from IT and its dual effects on BPR, IT investment priorities in BPR is narrated deeply.

本论文的创新点体现在五个方面：1）基于上述两种重组方式的高风险性，对它们的外延和内涵演变进行了分析，发现它们日益融合的趋势；然后结合核心能力理论和流程变革管理的思想对企业重组的概念进行了界定，将其分为&前重组&和&后重组&两部分，并对其内部关系进行了详细分析，同时应用经济学理论对其进行了解释。2）建立了重组风险的分析框架，并首次较为全面地分析和归纳了国外企业重组的风险因素，根据重组的过程和步骤以及项目管理的观点，将重组风险划分为计划、设计和执行3个部分，并在此基础上提炼出企业重组的风险指标体系。3）运用现场访谈、问卷调查的方法，调查了江苏省72家企业重组的风险情况，然后利用因子分析法对每一部分的每一风险因素进行实证分析，对风险指标进行了约减，建立了比较完善的适合我国企业的重组风险指标体系。4）建立了重组变革方案的选择模型，然后针对不同的重组方案提出了确定指标权重的目标优化模型，并基于三角模糊数之间两两比较的可能度概念，提出了一种重组方案排序法，从而可以有效地对各种变革方案的风险进行评估和比较。5）针对信息技术所造成的&生产率悖论&现象及其对重组的双重影响，建立了信息技术、企业重组和企业战略之间的整合关系模型，并对重组中信息技术投资的优先权问题进行了深入的阐述。

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。