查询词典 numerical computation

The numerical results indicate that the operator splitting method effectively suppresses numerical oscillations in the cases of high air bearing number. The numerical results show that both air lift force and pitch moment increase with the ratio of the slider's rail height to the air film characteristic height and the air bearing number, and finally reaches to stable value.

比较在不同轴承数下的气浮力和纵倾力矩发现：同一轴承数下，气浮力随气膜特征厚度减小而增加；当磁头槽台高度与气膜特征厚度的比值相同时，气浮力随轴承数增大而逐渐增加直到达到某一值后保持不变；纵倾力矩随轴承数增加而增大到某个最大值后减小。

Based on modern optimization theory and optimal control theory, this dissertation studies some questions as follows:1. The optimization model of parameter identification of three-dimensional geologic history numerical simulation, algorithm and its applicationGeologic history numerical simulation is a basic content of basin numerical simulation, and the porosity is the major parameter in the evolution and development process of oil-bearing basin. According to the sedimentation and burial mechanism, the physical and chemical principles of oil geology, the mudstone porositys non-linear parabolic partial differential equation has been established.

本文应用现代最优化及最优控制理论，对如下一些问题进行了研究： 1、三维地史数值模拟的参数辨识优化模型、算法及应用地史模拟是盆地数值模拟的一个基础性的研究内容，地层孔隙度是含油气盆地地史演化发育过程中的重要参数，根据地层沉积埋藏机理和石油地质的物理化学原理，通过引入数学物理方程概念，建立了泥岩三维孔隙度场方程，根据问题的特点，给出了方程的定解条件，对方程的动边界也给出了处理方法，并且证明了解的存在性与惟一性，在此基础上建立了以当今实测数据为拟合准则的三维地史数值模拟的参数辨识优化模型，这是一个含有二阶偏微分方程约束的泛函极值问题。

Taking Master CAM as an example, the paper introduces the technique of postposition dispose for numerical automatic control programming based on CAD/CAM integration, and explains by the example the process of postposition dispose for numerical control programming, generating the numerical control programming, and then producing and machining.

以Master CAM为例，介绍了基于 CAD /CAM一体化的数控自动编程加工中的后置处理技术，以及在当前条件下如何进行数控加工后置处理。

The classical cutting stock algorithm——column generation technology , and wrap up rectangle technology for abnormity are analyzed ; The development of AutoCAD with ObjectARX is studied and the generating method of cutting outline drawing and layout drawing were found out on the basis of analyses of the graph database structure of AutoCAD and the basic operation of it ; The process planning technology of plate material cutting orienting numerical control is studied a process planning method directly based on layout drawing is established ; The emulation technology in AutoCAD is studied and a kind of dynamic emulation method is put forward , which is realized by incrementally modifying graph entity ; The postposition of NC program of the integrated cutting system constructed on software plug-in is proposed , which can effectively solve the problem that it is difficult for a numerical control programming system to be common , which is caused by the difference of instruction format and control parameter between different type of numerical control machine .

分析了经典的矩形件优化排样算法——列生成法和针对异形件的矩形包络算法；研究了基于ObjectARX 的AutoCAD 开发技术，结合对AutoCAD 图形数据库结构及其基本操作的分析，给出了下料轮廓图和排样图的生成方法；研究了板材数控下料加工的工艺处理技术，建立了一种直接基于排样图进行的图形交互工艺规划方法；研究了在AutoCAD环境中的板材下料数控仿真技术，给出一种通过增量修改图形实体对象实现的动态仿真方法；提出以软插件技术构建集成下料系统的数控编程后置处理部分，能够有效解决因数控下料机床指令格式及控制参数不统一导致的自动编程软件系统不易实现通用性的问题。

During the four years study on the project, we develop a dynamical forecast model that describing the subtropical ridge surface. A new theory on the role of the land-sea thermal difference on the formation of the Subtropical High is advanced. It is concluded that in the summer subtropics over each continent and its adjacent ocean LO, SE, CO, and a double-dominant heating from west to east compose a LOSECOD heating quadruplet. The influence of the Eurasia continent on SH varies according to the seasonal variation. From the ideal numerical simulation it is shown the important role of the Eaiuan continent and the huge topography on the mechanism of formation and mantanence of the SH during the summer. It is verified by the numerical simulation that the extension of the subtropical continent into the tropics greatly enhances the " East Asian monsoon". Through the Rossby energy dissipation theory it is verified that the deep latent convective heating induces the onset of the South China Sea monsoon over the Bay of Bengal. The relationship and mechanism between the precipitaiton over the East Asia and the Subtropicla high is illustrated by the data. It is also found the close phase lock between the east-west shift of the SH and the disturbence of the east wind belt over the tropical troposphere. The interaction between the structure and activity feature of the SH and the Meiyu over the Yangtze-Huaihe river valley is revealed from the data. The numerical simulation verified the impact of the different SH pattern on the path of the typhoon.

本项目的研究发展了描述副热带高压脊面变化的动力模型，提出了夏季副热带地区四叶型非绝热加热分布型及相应环流拼图的创新理论；明确了大陆尺度的海陆热力差异在副热带高压形成中的作用；指出欧亚地形对副热带高压和气候的影响随季节变化而变化，通过数值试验证明春季青藏高原的感热加热对亚洲夏季风的爆发地点起了"锚定"的作用，进一步证实了副热带高压断裂和亚洲夏季风的最早爆发地点发生在孟加拉湾东岸；利用Rossby波能量频散理论证明了孟加拉湾深对流潜热释放诱导南海季风爆发的机制；揭示了东亚季风降水的季节内变化与西太副高的关系及机理；揭示了西太副高与东西风带中扰动之间的相互作用过程，指出西太副高的东西活动与热带对流层上空东风带扰动和中纬度西风带扰动的移动和锁相密切相关；研究了夏季淮河流域梅雨期间副高结构和活动特征及其与江淮暴雨的相互作用；验证了不同副热带高压形态对台风路径的不同影响；通过数值试验证明了欧亚大陆和青藏高原等大地形对副热带高压形成和维持的重要作用。

In practical application of numerical control lathe, the sice precision of numerical control turning can be conteolled and ensured effectively by effective steps considering the influence of geometrical Rarameters to the sice precision of numerical control turning .

在数控车床加工的实际应用中，针对刀具几何参数对数控车削加工尺寸精度的影响，采取有效的措施，使得数控车削加工的尺寸精度，得到有效的控制和保证。

Numerical integral method is applied in this paper to study this problem, hoping to provide a reliable, yet simple numerical model for the application in the ocean disposal of waster water.Compared with other numerical model, momentum integral method is simple.

其思想是建立在流动自相似假定的基础上，使流动的控制微分方程简化成常微分方程，并以边界条件使方程封闭，从而结合定解条件来预报浮射流的流动特性，如流速和浓度的分稚规律。

Impsons Integration: In numerical analysis, Simpson s rule is a method for numerical integration, the numerical approximation of definite integrals.

pecifically：：辛普森整合：数值分析中，辛普森法则是一种方法，数值积分，数值逼近定积分。具体来说

By the numerical analysis of the ultimate bearing capacity of two- and three-dimensional footing under combined loading mode, the results show that the effect of alteration of underground water lever on bearing capacity of three-dimensional foundation is more than on that of two-dimensional foundation, the effect of soil gravity on bearing capacity of three-dimensional foundation is more than that of two-dimensional foundation. At the same time, the numerical calculation process of ABAQUS indicates that whether the geostatic stress is balanced or not has great effect on the numerical convergence. In view of the effect extent of dilation angle of soil on the ultimate bearing capacity and the failure pattern of foundation, the condition of two-dimensional plane strain is higher than that of the three-dimensional foundation.

复合加载模式下，通过对三维矩形基础和二维条形基础进行数值分析，结果表明：黏性土地基中地下水位的变化，对三维矩形基础极限承载力的影响程度高于对二维条形基础的影响；在求解地基极限承载力的过程中，土体重度对三维矩形基础的影响明显高于对二维条形基础的影响，同时ABAQUS数值计算过程表明，地基土体地应力能否合理平衡，对数值求解过程中是否收敛有很大的影响；就土体剪胀角对地基极限承载力的影响程度而言，二维平面应变情况下土体剪胀角对极限承载力的影响比三维情况下的影响更明显，即土体剪胀角对条形基础极限承载力的影响高于三维矩形基础。

The results of numerical analysis show that the elastic modular and the poisson ratio have no effect on two-dimensional bearing capacity, but can affect the ultimate bearing capacity of three-dimensional foundations and control the convergence and precision of finite element calculation; the earth pressure coefficient controls the geostatic stress of foundation, sequentially affects the ultimate bearing capacity of foundations and the convergence of numerical calculation. When calculating the ultimate bearing capacity of undrained saturated foundation, the complete formulation exists shear locking, and reduce formulation exists hourglassing, so the hybrid formulation is suitable to imitate the geomaterial. When the soil obeys nonrelevent flow rule, the yielding function is different from potential function, and the elastic-plastic matrix of soil is asymmetric, so the unsymmetry numerical solver and appropriate finite element mesh is required.

研究结果表明，土体弹性模量和泊松比对二维基础极限承载力没有影响，但是影响着三维矩形基础的极限承载力，控制着ABAQUS数值算法的计算精度与收敛速度；地基土压力系数控制着地基土体中的地应力平衡，从而影响着二维条形基础和三维矩形基础的极限承载力和地基破坏包络面；对于不排水饱和软黏土地基，常规的完全积分单元会造成剪力自锁现象，而减缩积分单元则存在过于柔化的现象，故采用杂交单元来模拟较合适；当土体服从非关联流动法则时，屈服函数与塑性势函数之间存在差异，从而导致土体弹塑性矩阵呈现非对称性，在有限元计算中必须采用非对称数值解法，并且合理地划分单元才能对极限承载力进行准确求解。

There are different types of personal loans available.

有许多不同类型的个人贷款优惠。

The above mentioned teaching model of spiral rising can be used to avoid rigidness in teaching.

上述螺旋式上升的教学模式，可以避免教学形成模式後的僵化现象。