查询词典 NC

In untreated nitrocellulose membranes, the hydrophilicity of the material is a direct function of its pore structure.

对于未处理的NC膜，它的亲水性是其孔径结构的直接功能。

A new technology,which is called non-interference normal tracking for NC curve grinding was presented.

将快速点磨削技术引入到曲线磨削过程中，提出了曲线磨削中砂轮对工件轮廓实施法向跟踪磨削的新方法。

The interpolate algorithms of three-order NURBS curve and double three-orders NURBS surface are presented. The expressions of partial derivative and normal curvature of NURBS surface are derived by the theory of differential geometry. The geometric characteristics of different curvature area of the free-form surfaces are analyzed in detail. All these work lays a theoretical foundation for constructing the cutter location calculating model of free-form surfaces NC machining. 2 On the basis of analyzing the methods of cutter path generation, the standard of evaluating the various methods of cutter path generation is presented. The method of generating cutter path with constant scallop height is presented for the first time.

本文以提高复杂曲面多坐标数控加工精度和加工效率为目的，在对国内外研究现状进行深入分析的基础上，对数控编程中各环节的关键技术问题进行了深入研究，主要内容包括以下几方面： 1 分析了复杂曲面各种造型方法的优缺点，给出了根据各种边界条件所确定自由曲面的NURBS表示方法以及三次NURBS曲线曲面反算算法；用微分几何理论推导了NURBS曲面的偏导矢及法曲率计算表达式；对曲面不同曲率特性区域的几何特征进行了深入分析，为建立复杂曲面的数控加工刀位计算模型奠定了理论基础。

Therefore, we stress the day-to-day "NC", in essence, is that computer numerically controlled.

所以我们日常讲的"数控"，实质上已是指"计算机数控"了。

The results show that the penetrability of powder loads can be improved when suitably reducing bulk density and grain size of gun propellant, increasing nitrogen content of NC and choosing oblate spheroid explosive respectively under the constant test con

结果表明，在其它试验条件不变的条件下，适当降低发射药堆积密度、适当提高发射药中硝化棉含氮量、选用恒面燃烧的扁型药、降低发射药粒度均有利于提高射钉的穿透能力。

Right shielding and good grounding is important means to stabilize work of NC system and to obviate the disturbances.

屏蔽和接地两大技术之间的联系密切，如果应用得法，可以明显提高系统的抗干扰能力。

Nowadays, the open-loop control system is widely used in the control of economic type NC working table.

提供了一种经济型数控工作台闭环控制的解决方法，并给出了控制电路及算法，有效地提高了数控工作台的精度。

This dissertation study the machining method for multi-axis NC high speed milling, tool path generation calculation and interference treatment and optimum programming.

本文研究了多坐标数控高速铣加工中的加工方法、刀具轨迹生成计算以及干涉处理和优化计算方法。

A method of the order selection of polynomial model for geometric errors modeling for NC machine tool was presented.

提出了一种针对数控机床几何误差多项式模型的阶数选择方法。

Before machining,the NC programs must be checked to examine whether thetrajectory is right or not , whether the tool will overcut or without cut.

在数控加工中随着工件复杂程度的增加，尤其是鞋楦这样的复杂曲面，其数控加工程序的正确性无法靠人工检查。

The basic concept of FOP can be summarized as to further optimize effective prescription according to the standard of curative effects and with the aid of modern science and technology and theories of traditional Chinese medicine.

其基本内涵可概括为：以确有疗效的中药复方为研究对象，以现代科学技术和传统中医药理论为技术支持，以该复方所治病证的药效响应为评价标准，以优化重组疗效更优的新复方为研究目的。

Ever since our world has been a world, native forests have been indiscriminately exploited by man.

自从我们的世界一直是世界原生森林被任意剥削人。