查询词典 multistep method

A new nonlinear multistep method is constructed based on the implicit Euler method in this chapter, named Schur product multistep method.

本文在隐式Euler方法的基础上构造了一种非线性多步法，即Schur积多步方法。

Otherwise, we construct an exponential fitting schur product multistep method based on schur product multistep method and exponential fitting method.

数值实验表明，该方法与传统方法相比，在同等步长下，方法的计算精度远远高于传统方法。另外，本文将此类指数拟合方法与Schur积多步方法结合起来，构造了一类指数拟合Schur积多步方法。

In Chapter 3, we investigate the delay-dependent stability analysis of linear multistep methods when they are applied to the neutral delay differential equations. We state a necessary condition for any linear multistep method applied to the neutral delay differential equation to be Nτ(0)-stable.

在第3章中，考虑了中立型延迟微分方程线性多步法依赖于延迟的稳定性分析，给出了任意线性多步法是Nτ（0）-稳定的一个必要条件。

Main points of the thesis are as follows:(1) The main function models and information relations between these models in the CAPP system in the integrated CAD/CAM project are explained, a new process plan design method is mentioned based on analyses of process plan design. This method is based on the process plan prototype, and develops the prototype little by little until the perfect process plan is completed, the prospect of this method is discussed;(2) The feature abstracting rules and methods are studied, a feature coding system is developed based on GT, all the defined feature models are described by the mathematical methods;(3) The integrated method of CAD/CAPP based on features is mentioned, this method defines a feature exchanging model, and develops an interface software to exchange design data into technology data base, this technology data base includes the design and technology information of the parts;(4) The process plan reasoning method based on features is created, this method uses Mycin algorithm to solve the reasoning of the feature process plan. A process plan making system is developed. In this system part process plan is made by the semi-intelligent method, this method uses the feature reasoning, feature process chain searching and man-computer talking together;(5) The main structure of the HOPE system is introduced, a shaft drawing and its process plan made by this system are shown, the data process problem in process drawing making is also discussed;(6) A new method of describing process rule is introduced, this method uses IfThen rules and neural nets weight values together to describe process rules, the BP algorithm is adopted in this method;(7) The optimal machining sequence problem of the process steps on the same fixturing is discussed, optimal algorithms SA is applied to solve this problem, the result shows that this method is more efficient than the traditional method;(8) All jobs in the thesis are summarized. In order to carry out the research in the future, some rational proposals are given.

全文论述的内容主要有下列几个方面：(1)较为系统地阐述了CAD／CAM一体化工程项目中CAPP系统的主要功能模块及其信息流程，在分析工艺设计过程的基础上，提出了基于特征原型的渐进式工艺设计方法，并探讨了该方法的应用前景；(2)研究了零件特征提取的原则和方法，在成组技术的基础上，开发了一套基于特征的分类编码系统，并在提取零件特征的基础上，定义了零件特征的数据模型，开发了基于轴类零件特征的参数化设计系统；(3)研究了基于特征的CAD／CAPP集成的方法，通过定义零件特征数据模型的存储结构，开发了将设计数据转换到工艺数据库中的接口程序，为后续的CAPP系统提供必要的零件形状和工艺信息；(4)研究了基于特征的工艺推理方法，将Mycin算法应用到工艺决策中，开发了基于特征的工艺推理及工艺方案生成系统，在系统中综合运用特征推理、特征加工工艺链查询及人机对话相结合的半智能化方法确定零件加工工艺；(5)介绍了整个HOPE系统的总体结构，通过运行HOPE系统绘出了一轴类零件的零件图，并生成了该零件的加工工艺方案，初步探讨了基于特征的工序图生成技术中数据处理问题；(6)研究了工艺设计过程中知识如何有效表示的问题，提出了将显式的IF-THEN规则表示与隐式神经网络权值表示相结合的工艺知识表示方法，并利用BP算法进行了工艺知识表示的初步研究；(7)研究了工艺设计过程中同一安装下工步优化排序问题，利用神经网络中基于模拟退火的理论来解决该工步优化排序问题，实践证明该方法较传统的算法具有更高的效率；(8)总结了本文所进行的研究工作，为今后进一步开展工作提出了较为合理的建议。

In this paper Ⅰ successfully applied these methods to fault diagnosis, and presenting some new innovative machinery fault diagnosis method; First Ⅰ present a new gear wornout fault diagnosis method, this method use the vibration signal's time-frequency attribute and instantaneous phase undulation to accurately detect gear's fault, and by comparing with the traditional frequency domain analysis method, this method reveals that many nonlinear and nonstationary characteristic exist in gear's vibration, this tell us that if we use frequency domain analysis method without pay attention to the signal's characteristic, we could get wrong diagnostic result; Then Ⅰ present a new bearing fault diagnosis method, this method use ATVFD and Hilbert transform to do envelop demodulation,Ⅰ analyze the envelop with time-frequency method and find out that this method is more accurate then traditional method.Ⅰ also explain that the modulation of the fault to the carrier wave may also be non-stationary and nonlinear; Finally Ⅰ present a cylinder pressure measurement method of diesel engine by means of vibration, cylinder pressure is an important parameter of diesel engine fault diagnosis, the pressure measuring is simplified a lot by this method,Ⅰ also use the ATVFD and time-frequency analysis to realize it.

本文中将上述理论方法成功地应用到故障诊断中去，提出了几点创新性的诊断方法；提出了一种齿轮磨损故障诊断的新方法，该方法利用振动信号能量的时频域分布特征与瞬时相位波动特征可以进行精确的齿轮故障诊断，并通过与传统的频域诊断方法的比较，揭示出齿轮振动中存在的明显的非线性与非平稳特征，说明了不加选择地利用频域分析方法进行齿轮故障诊断很可能会得到错误的诊断结果；提出了一种轴承故障诊断的新方法，该方法利用ATVFD分解与Hilbert变换进行包络解调，并对解调得到的包络信号进行时频域分析，可以实现更加准确轴承故障诊断，说明了故障对载波信号的调制往往也是非平稳与非线性的；提出了一种利用振动信号进行柴油机汽缸内压力检测的新方法，柴油机汽缸压力的变化是柴油机故障诊断的重要参数，利用振动方法可大大简化汽缸压力的检测过程，该方法也是综合利用ATVFD分解与时频域分析方法实现的。

This train classifies "information carrier adhering to the build" as design elements, and probes into integrated design method of it and single building separately: method of definite position, method of definite form and method of combination; Then, this train probes into integrated design method of it and colonys building , that bases on the cognitive design method: method of rhythm controls,method of node outstanding, and that aims at the design method to protect: method of protect original, method of repairing and method of renewal.

本文的第四部分提出了一体化设计的思路，将建筑附着信息载体作为设计元素，探讨了它与建筑单体一体化设计的方法：定位法、定形法、混合法；以及它与建筑群体一体化设计时，基于认知的设计方法：节奏控制法、节点突出法，旨在保护的设计方法：存真法、修缮法、更新法。

Euler method, single step method and one-leg multistep method are considered as maily numerical computation schemes.

本文分别采用显式Euler法，单步θ-方法和one-leg方法作为数值计算格式。

A non-stiff transformation method is presented in this paper, based on the above theory, general Schur product multistep method is put forward.

本文讨论了刚性常微方程的非刚性转化方法，在此基础上，获得一类广义Schur积多步法（通过这种非刚性转化方式，显式Euler方法将成为一个A-稳定的方法）。

It is proved that if the RungeKutta method and the linear multistep method are of order p, then the numerical Hopf bifurcation value is an approximation to the Hopf bifurcation value of the equation itself of the same order p.

证明了如果Runge-Kutta方法和线性多步法是p阶的，那么数值Hopf分支值以相同的阶数p逼近于方程本身的Hopf分支值。

Multistep method is the first method applied to DAEs.Because of some reasonsin history,all algorighms for DAEs come from those for stiff ODEs,mainly thebackward difference formula.

多步法是最早用于直接求解微分代数方程的方法，由于历史上的原因，长期以来使用的公式都是由刚性常微分方程的求解公式导出的，主要是向后差分公式。

"Yes, now you can give yourself airs," she said, you have got what you wanted.

"对了，您现在高兴了，"她说道，这是您所期待的。

Then the LORD said to me: Rebel Israel is inwardly more just than traitorous Judah.

上主于是对我说：＂失节的以色列比失信的犹大，更显得正义。