曲面

Uncertain singular systems are transformed into the form of restricted equivalence by a nonsingular linear transformation. By the method of Lyapunov function, a new terminal sliding mode control strategy based on the form of restricted equivalence is proposed for the first time, and the hypersurface of a special terminal sliding mode is given. A terminal sliding mode controller is designed correspondingly such that the motion of sliding mode can be guaranteed and the systems state variables can converge to the equilibrium point in a finite time.

通过非奇异线性变换把不确定奇异系统变换成受限等价形式，利用Lyapunov函数方法，首次提出了一种新的Terminal滑模控制策略，给出了特殊的Terminal滑模超曲面，设计了相应的滑模控制器，实现了滑模运动，保证了系统状态变量在有限时间内收敛到平衡点。

They are as following: to establish the selection method of the slaving designed quality functions according to the interrelationship among designed quality functions; to construct the measurement functions of the optimality robustness with the hypersurface characteristics around the current iterative point of designed quality functions.

具体地，根据设计性能函数之间相互关系给出了处于支配地位设计性能函数的选择方法；利用设计性能目标函数在当前迭代点附近的超曲面特征，构造设计性能目标函数的最优性健壮度量函数；按照系统有序化设计模型的最优解应同时具有可行性健壮与最优性健壮的要求，通过计算设计性能目标函数与约束函数对设计变量的波动与非设计参数的波动的一阶敏度来确定系统有序化设计模型中的健壮参数；并以此为基础建立了进一步考虑非设计参数波动对设计变量波动有影响的后健壮分析方法。

Because this method has smaller local relative errors and fast calculation efficiency,it is applicable for 2-D data with low gradient such as hypsography data and ray tracing time tables.

由于此方法具有局部误差小、计算高效的特征，可以适用于数据梯度较小的二维系统数据的曲面拟合和数据压缩，如地形高程数据和射线追踪走时表。

This method needs no connectivity information about data points. The contradictory of "smooth" and "fit" can be mediated by anchoring an imaginary spring between each data point and deformable curve or surface.

该方法不必要求数据点有序的条件，通过在数据点与曲线和曲面之间连接假想弹簧，可以克服"光顺"和"插值"的矛盾，得到所需形状。

Implicit function based surface reconstruction has been a challenging work for decades in computer graphics field.

通过隐函数拟合实现曲面重建是计算机图形学领域中一项重要而有挑战性的工作。

Integral of one variable functions, improper integral and its convergence properties.

本课程的主要内容包括：1 各种极限运算，其中包括数列极限、函数极限以及上、下极限；2 一元函数的微分学，包括微分和导数的运算法则、微分中值定理及其应用等；3 一元函数的积分和广义积分及其收敛性；4 级数及其收敛性，包括数值级数的收敛性和函数项级数的各种运算和性质；5 多元函数的微分学及其应用，其中很多方面与一元函数的微分学近似，需要注意它们之间的区别；6 多元函数的积分学，包括多重积分的性质与计算，多重积分的的应用等；7 曲线、曲面积分及其应用；8 含参变量积分的计算与性质；9 Fourier 级数及其应用，等等。

For FSS used in curve, the use of this method can weaken the sensitivity of the center frequency to angle incidence.

此方法可以应用在曲面FSS上以减小中心频率对角度的敏感性，以球壳上应用的FSS为例，给出了应用模型。

In order to approximate the original curve surface, bring forward the rule and the way for optimization to deal with the included angle among elements is the key point of the algorithm.

需要先光顺零件边界是面向CAE的汽车覆盖件模面设计区别于CAD中工艺设计的一个最明显环节，是保证工艺补充曲面光滑性的前提条件。

The intensity formula shows that the light intensity at any point of a curved surface is not only related to the amplitude at the point, but also related to the included angle between the Poynting vector and the direction of the local differential surface element.

这个推广的定义式表明，曲面上任一点处的光强值都不仅与该处的振幅有关，而且还和该处的时间平均能流密度与面元方向的夹角有关。

An identification algorithm for tool interference in NC machining is presented based on the fuzzy inference techniques and pattern recognition theory.

基于模糊推理的自由曲面描述方法和模式识别理论，提出一种适用于不同刀具类型并可同时考虑刀具底面干涉和侧面干涉的刀具干涉判别算法。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。