查询词典 numerical code

The main works of this paper are as follows.First, according to the three-step method, 1-D unsteady flow model in river network is introduced. A new topological structure is presented to describe and store the topology information and data in river network ,which realises the connection between GIS and the numerical program of hydraulic calculating and turns the program into a universal one .A new formula of internal boundary conditions with double-recursion algorithm is deduced, and the relationship of recursive coefficient between imaginary channel length and non-imaginary channel length is presented ,which makes sure that the model can comprise the numerical simulation of the internal boundaries such as side pipe outflow ,barrage, slice gate and drainage pump station.

主要工作如下：(1)根据三级解法建立了一维河网非恒定流模型，并提出了一种新的数据结构来描述和储存河网拓扑信息，方便了GIS平台和数值计算程序的衔接，实现了三级解法程序的通用性；从河段方程组出发，根据虚设河段法推导出了内边界条件的双追赶法公式，指明了虚设河段的追赶系数和非虚设河段追赶系数的关系，从而使模型可以模拟集中旁侧入流、堰、闸、水泵等内边界对行洪过程的影响。

This dissertation realizes one computer numerical control system for two and half axises upright numerical control milling machine using computer software, hardware and DSP technology.

本论文利用计算机软、硬件技术、DSP技术，实现了用于两轴半立式数控铣床装置的计算机数控系统。

There are two modeling methods used in this research area, that is analytical method and numerical method. Analytical method can be used to analyze the sound pressure within enclosures, and to analyze the control mechanisms theoretically, however it can be used for regular cuboids only. Numerical modeling method can manage enclosures with arbitrary boundaries, nevertheless, the results obtained using this method are dispersed sound pressure. It is hard to conduct real time control with this method. The two modeling methods have their own inherent defects.

对于封闭空间的结构声辐射，目前有解析建模和数值建模两种建模方法，解析建模方法可以从理论上对系统进行分析，探讨消声机理，但它只适用于长方体等规则封闭空间；数值建模方法不受空间边界形状的限制，得到的是空间声压的离散结果，难以用于实时控制，两种方法都存在着局限性。

From the analysis and comparing with different illustration, it proves that the numerical model used in this paper is correct and the results of numerical study are in agreement with the facticity about the flow field.

通过对数值计算结果的分析和比较，证明数值模拟所用的计算模型是有效的，较好地反映了旋流器内液固两相流场的物理真实性。

Both numerical control induction machine tool X-Z axis and slew workbench of part drive by numerical contral, the coil feed motion is drived with servo motor which joins to ball screw assemblly to carry out.

数控感应淬火机床X-Z轴和工件的回转工作台均采用数控驱动，感应头的进给运动通过伺服电机带动滚珠丝杠来实现。

Both numerical control induction machine tool x-z axis and slew workbench of part drive by numerical contral,the coil feed motion is drived with servo motor which joins to ball screw assemblly to carryout.

本设计课题紧跟现代数控技术的发展，针对具有曲线形状的板类、盘类及需要精密分度的零件表面热处理要求而设计。

This paper introcluces the design and calculation procedure of vertical feed ball screw auxiliary in X6132 milling machine numerical control transformation,It also discusses consciously design the choice of accuracy,The purpose is to provide design reference for numerical control machine transformation of other kind

本文介绍了X6132铣床数控改造中纵向滚珠丝杠副的设计计算过程，并对选择精度的3个原则作了简单介绍，可供其它类型的机床数控改造滚珠丝杠副设计及选用参考。

In chapter 1, the history of numerical simulation of extinguish fire is introduced. The technique and theory of fire suppression by water mist are presented, and the sort of numerical simulation of extinguish fire is discussed.

第一章回顾了细水雾灭火过程数值模拟的发展历程，介绍了细水雾灭火技术和灭火机理，同时阐述了火灾数值模拟的分类，以及国内外在灭火数值模拟方面的研发现状。

In this dissertation the"Penalty"finite element method was employed to compute the velocity of the three-dimensional flow of power-law fluid in a profile die. In order to decrease the needed computer memory and raise the stability of numerical simulation, a set of decoupled methods such as PFEM, pseudo-body force method and transformation of momentum equation to the elliptic equation was developed to establish the general finite element equations to compute the distributions of velocity and viscoelastic stress of the three-dimensional viscoelastic flow of the Phan ThienTanner fluid in a profile die. During numerical simulation of the extrudate swell of the PTT fluid, the flow in the die and out of the die was analyzed separately, which demands less computer memory.

本文建立了求解挤出口模内幂律流体流动速度场的通用三维罚有限元模型；对于非线性粘弹性的Phan Thien-Tanner流体，为了降低模拟计算对计算机硬件的要求，并使模拟计算更加稳定，采用了一种去耦算法，包括罚有限元方法、拟体力方法和动量方程的椭圆类方程转化方法，并建立了求解速度场和粘弹性应力场的总体有限元方程；对于PTT流体的挤出胀大问题，提出了挤出胀大熔体口模内外分离模拟法，这样可以显著降低数值模拟对计算机硬件的要求。

Furthermore the numerical flux from the Riemann solver is delicately expressed in a compact manner, say by the well known Godunov flux function, which paves the way to full investigation of numerical approximations.

由上述的Riemann解所提供的数值流通量经仔细验证后可以被简洁地表示为Godunov流通量的函数值，这为研究一般意义下的数值逼近铺平了道路。

Pachomius manual labour was organized as an essential part of the monastic life; and since it is a principle of the monks as distinguished from the mendicants, that the body shall be self-supporting, external work of one sort or another has been an inevitable part of the life ever since.

根据圣pachomius体力劳动组织作为一个重要组成部分寺院生活；以来，这是一个原则的和尚，作为有别于乞丐，该机构应自支撑，对外工作的这种或那种已一个必然的一部分，生活至今。

In order to study the effects of parametrical rolling on the ship movement and tilts, in allusion to ship's navigating in regular following waves, the equation of ship rolling motion is transformed into normal Mathieu equation by proper variable replacement when strong parametrical excitation in restoring moment varied according to sine or cosine wave.

为研究参数横摇对船舶运动和倾覆的影响，通过对船在规则波上随浪航行时，恢复力矩中出现的1个以正余弦规律变化的强参数激励项进行适当的变量置换，将船舶的横摇运动方程转换成标准形式的Mathieu方程。