查询词典 numerical method

Based on chapter two, In chapter three, the method of multiple scales is introduced to the study of the multiple-dimensional nonlinear stochastic systems under random external excitation. Using method of multiple scales, we strictly deduce the equation of modulation of amplitude and phase. The effects of random excitations are analyzed; numerical simulations verify the results. Theoretical and numerical simulations show that when the intensity of the random excitation increases, the nontrivial steady state solution may be changed from a limit cycle to a diffused limit cycle.

在第二章基础上，第三章将多尺度法引入到相应的随机系统的研究中；严格推导了系统的约简方程，用矩方法求出稳态解应满足的方程，获得一些结果；并且数值模拟结果与理论推导的结果是一致的；并注意到，与其对应的确定性系统相比较，系统响应从周期解变为近似周期解，系统的相轨线从极限环变为扩大的近似极限环；随着激励带宽的增大，此扩大的近似极限环的宽度将增大。

According to fully implicit method, seepage model of low-permeability fractured gas reservoirs are discretized with finite difference method, and corresponding numerical model, coefficient matrix and matrix element are obtained; then based on modern software engineering, numerical simulation software was correspondingly developed with Fortran95 programming language

按照全隐式离散化方法，采用有限差分方法对低渗裂缝性气藏渗流数学模型进行了离散，得到了相应的数值模型、系数矩阵和矩阵元素。然后基于现代软件工程的基本思想，用Fortran95语言开发了相应的数值模拟软件

Based on the lumped mass method and Newton's second law, the numerical model of the force and movement response for fishing nets in current was set up, and then the dynamic deformation and the equilibrium configuration of the plane net in current along the positive direction of x-axis were studied by means of computer numerical simulation method.

基于集中质量点法和牛顿第二定律，建立了网衣在水流作用下的受力和运动响应数学模型。

Based on the theory of contact dynamics, the dynamic model with clearances of sizing press roll was established using the method of numerical simulation. The paper studied the effect of clearances on contact force inner Mechanism joints detailedly by the method of numerical integration of fix step length four orders Runge-Kutta.

基于接触动力学的理论，利用数值模拟的手段建立了调宽机含间隙的动力学数学模型，采用定步长四阶Runge-Kutta数值积分的方法，详细研究了运动副内间隙对接触力的影响规律。

In order to control the propagation of errors and enhance the accuracy of numerical solution, the wilson-θ method is modified and the numerical stability of modified wilson-θ method is analyzed.

为有效控制误差的传递，提高计算精度，对Wilson-θ法进行改进并分析了改进Wilson-θ法的稳定性。

Do some tentative analysis of the tunnel lining by numerical manifold method. the idea is given that combining regular mesh with finite element mesh and using low-order and high-order cover displacement function in numerical manifold method, it make preprocess and program analysis, precision and efficiency for coordination.

4利用数值流形方法对隧道工程中衬砌结构进行了尝试性的分析，提出了结合规则网格和有限网格并行、高低阶覆盖位移函数混合计算的思想，以达到前处理和程序计算、计算效率和求解精度的协调。

The primary studying works and characteristics:1 To summarize reinforcing theory of cement mixing pile composite foundation2 To analyze the primary mechanics characters and changing rules of cement mixing pile, based on analysis of test data both indoor and outdoor.3 To discuss siding frictional resistance, ending resistance, ultimate bearing capacity of simple mixing pile and effectiveness factor of grouped piles, loading ratio of soil between piles under cushion cap of grouped piles and stress ratio of pile and soil and so on, and use many computation method and experimentation method to ensure bearing capacity of mixing piles composite foundation.4 To point out and analyze eight sides flaws and problems of the bearing capacity calculation method of mixing pile compositefoundation which ensured by national and normative method/ formula.5 To apply test results of loading tests and a few settlement observation data, use gray theory to predicate ultimate bearing capacity of deep mixing piles, actual example demonstrate engaging between theoretical predicted value and actual value.6 To apply groovy layerwise summation method to discuss entity piles method, double foundation method, equivalent layerwise summation method and consolidation theoretical method and so on, especially by combination of engineering example, use FEM to calculate or discuss the settlement and changing rules of composite foundation.7 To discuss problems of critical length of composite foundation by combination of engineering example and numerical analysis method, and analyze the contrast of critical length between simple pile load and most area load of composite foundation, not only critical length of composite foundation is relative to modulus ratio between piles and soil, but also upside load distribution area of composite foundation.

主要的研究工作与特色为：(1)总结了水泥搅拌桩复合地基的加固原理；(2)在对室内外试验资料进行统计分析的基础上，系统分析了搅拌桩水泥土的主要力学特性及其变化规律；(3)探讨了搅拌单桩的侧摩阻力、端阻力、极限承载力及群桩效率系数、群桩承台下桩间土荷载分担比及桩土应力比等，提出用多种计算方法并结合试验方法来综合确定搅拌桩复合地基的承载力；(4)明确指出和分析了按国家有关规范的方法确定搅拌桩复合地基承载力所存在的八个方面的缺陷与问题；(5)利用过去没有加载至破坏阶段的载荷试验成果和较少的沉降观测数据，尝试了用灰色理论预测深层搅拌桩的极限承载力，实例表明理论预测值与实测值吻合较好；(6)在常规分层总和法的基础上，探讨了复合地基沉降计算的实体墩基法、双层地基法、等效作用分层总和法、固结理论法等，特别是结合工程实例，用有限元数值计算等方法计算和讨论了搅拌桩复合地基的沉降及其变化规律；(7)结合工程实例，用数值分析方法探讨了复合地基临界桩长的问题，指出和分析了单桩荷载下的临界桩长与复合地基大面积荷载下的临界桩长存在很大的差别，复合地基的临界桩长不仅与桩土模量比有关，而且与复合地基上部荷载分布面积有关。

The presterssed anchor cable frame combined with backwall, drainage is necessary due to longtime sability and permanent utilization.Firstly,according the study of engineering of geology situation of the high slope, the mechanism of deformation failure and the major hazard of the high slope of PanMei is analysed comprehensively.And the whole slope is divided into two different geology enginnering areas:Western slope(1160 section plane -1240 section plane)and Eastern slope(1240 section plane -1320 section plane). The result of 3D numerical simulation is the same as geology judgement. Later,slope cut (1:0.75) is implemented based on the engineering comparison and criterion.Meanwhile, Limit equilibrium method , Monte Carlo Probabilistic slope stability the stability , Sensitivity analysis and Finent element method of for assessing the cutted slope stability is carried out. The result indicates that Western slope is instable, Eastern slope is relatively stable.So much attention should be paid to Western slope.Different reinforcement measures in different areas are given according to its stability and meet economical request. Gravity wall is introduced in accordance with landform in order to prevent small falling at the foot of the high slope ,which will be a threat to the high slope stability. Handling measure is also applied to Eastern slope. At last,FLAC3D numerical analysis shows the feasibility and reasonableness of the handling measure of the high slope.

论文首先研究了边坡的工程地质条件，全面分析边坡的变形破坏机制和边坡的主要地质灾害，将边坡分为西段不稳定边坡区(1160剖面～1240剖面)和东段相对稳定边坡区(1240剖面～1320剖面)，通过三维数值模拟再现了边坡在自重作用下的破坏机制和过程；在此基础上通过工程类比和规范要求，确定按照1：0.75进行放坡处理，并分析了放坡后边坡的稳定性状况，分别通过极限平衡法、蒙特卡洛法概率分析、参数敏感性分析和有限元稳定性计算等多种方法对边坡在各种工况下的进行稳定性研究，计算结果表明，西段边坡较之东段边坡稳定情况差，是边坡支护的关键之处，而东段边坡相对是稳定的；边坡的综合治理措施选用的是框架锚索并结合挡土墙和排水工程，治理设计根据不同区段的稳定性情况采用不同的支护结构，做到了经济合理的要求；在边坡的坡脚设置重力式挡土墙，防治边坡小规模的崩塌，会对上部的锚索支护护造成不利影响，进而影响边坡的稳定；东段边坡的填方区也给出了治理对策；最后通过三维显示拉各朗日有限差分程序(FLAC3D)模拟了高边坡放坡和支护效果，论证了治理措施的有效性和合理性。

Incurrent research, aiming at the rupture problem engendered in the shooting process of acertain 5.56mm automatic rifle, the strain and stress distributions on the cartridge caseunder the action of axial pull have been analyzed. Based on the theories of elastic-plasticmechanics and contact mechanics, a mathematic and physical model of the cartridge-caseand chamber system has been set up; and based on the platform of the general softwarepackage APDL of ANSYS for finite element analysis, a parameterized model of thecartridge-case and chamber system has also been established. The method for nonlinearFEA has been adopted to analyze the stress distribution on the entire cartridge-case andchamber system, and the method of contact element has been employed to investigate thecontact stress between the cartridge case and chamber, and then the influences of frictioncoefficient and locking space on the static and dynamic stress and strain response of thecartridge case and chamber to the action of power gas have also been discussed. On thebasis of a lot of numerical tests, a kind of element Plane13, which is concentrated incoupled computation of heat and construction, has been used finally to simulate thetransient response of the cartridge-case and chamber system to the power gas. Throughloading the temporary thermal characteristics of explosive gas in the procedure of emulate, the corresponding transient thermal stress distributed on the entire system under thecombined load of transient thermal stress and transient pressure has been obtained. Owingto these comprehensive considerations, the numerical results obtained in this paperrepresent the actual situations comparatively exactly.

本文针对某5.56mm自动步枪在工作中出现断壳的问题，分析了弹壳在轴向拉力作用下的应力应变；基于弹塑性力学及接触理论，建立了弹壳弹膛系统的数学、物理学模型，在通用有限元ANSYS软件的参数化建模工具APDL平台上，建立了弹壳弹膛系统的参数化模型；采用非线性有限元法计算了弹壳弹膛系统的整体应力，引入接触单元法分析弹壳和弹膛的接触压力，探讨了在不同的摩擦系数和不同的闭锁间隙对弹壳弹膛静、动态响应的影响；本文进行了大量的尝试，最后确定采用热、结构耦合单元Plane13，在计算中加载了火药气体的温度历程，成功的获得了弹壳弹膛系统在瞬态的热载荷和瞬态的压力载荷同时作用下弹壳弹膛系统的热应力数值解，考虑因素全面，比较真实的反映了弹壳弹膛系统在火药气体压力和热载荷下作用的情况。

The velocity-stress pseudospectral method, an efficiently numerical modeling method, is easy to implement, with a high computation efficiency and can overcome numerical diffusion of the frequency efficiently.

模拟结果表明，伪谱法是一种有效的地震波数值模拟方法：易于实现，计算速度快、计算效率高，其计算速度是有限差分方法的数倍，能有效克服数值频散。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。