不变的

This paper analyzes the frequency characteristics of comb filter and the principle of using comb filter as decimation filter.

文章分析了梳状滤波器的频率特性及其作为抽取滤波器的原理，特别指出了此种滤波器具有对Σ－△调制器成型的量化噪声的频谱形状保持不变的特性。

Objective To study the power spectrum density of blood flow ultrasonic Doppler signal using wavelet analysis. Method Doppler signal of blood flow in human common carotid artery was studied with wavelet scalogram analysis, an affine smoothing Wigner Ville transform with a constant "Q" character. Result Wavelet scalogram of blood flow ultrasonic signal had a higher distinguishability than STFT spectrogram in the low frequency portion, but had poorer decussation terms than spectrogram.

对于平稳信号的处理工具仍然是Fourier变换，但是，在实际应用中的绝大多数信号是非平稳的，现在看来处理非平稳信号的主要工具将是小波变换，这主要是因为传统的Fourier变换分析信号时，时间和频率分辨率精度是固定不变的，而利用小波变换分析信号，在信号高频段时间分辨率精度也较高，在信号低频段频率分辨率精度较高，这很符合非平稳信号的特点。

Head in the disk rotational speed and the speed of operation remain unchanged, the same time, head-to-disk can visit some of the region.

在磁盘转速和磁头的操作速度不变的情况下，相同的时间内磁头所能访问到磁盘的区域是一定的。

I like it just the appearance, Rou Rou's pity, the color of the United States and the United States, and its petals is a multi-jaw, and layer after layer, and its florid is constant love, uphold.

我喜欢它的单单的样子，柔柔的怜惜，美美的颜色，它的花瓣是多瓣的，一层又一层，而它的花语是不变的爱，坚持。

His features were like his sister's, but in her, everything was radiant with joyous life, with the complacent, never-failing smile of youth and life and an extraordinary antique beauty of figure. The brother's face on the contrary was clouded over by imbecility and invariably wore a look of aggressive fretfulness, while he was thin and feebly built.

他的面部和他妹妹的一模一样，但他妹妹那乐观愉快的、洋洋自得、充满青春活力、朝夕不变的微笑和身段超人的古典美，使她容光焕发，倾城倾国；反之，哥哥的长相却显得愚昧昏庸，总是表现出十分自信和不满的神态，他身子既瘦且弱，疲软无力。

Art is an open and mobile system with variable meaning, for there's no immobility in the rules of art.

艺术是一个开放的、流动的体系，艺术的含义是变化的，没有固定不变的艺术规则。

The using degree of information has close connection with the development of signal processing .traditional signal processing object system limit to the linear system of time invariability, suppose that the signal is calm .

信息的利用程度和信号处理技术的发展密切相关。传统的信号处理的对象系统限于时不变的线性系统，并假设信号是平稳的。

For k≥1, an isometry φ between codes over Zsubscript P(superscript k+1 and codes over Z(subscript P^2) is introduced and used to give a generalization of the Gray map φ: Z(superscript n subscript 4)→F(superscript 2n subscript 2). Furthermore, by means of this isometry, the concept of negacyclic codes is extended to codes over the ring Zsubscript P(superscript k+1. A characterization of these codes in terms of their images under φ is given. It is also shown that the generalized Gray map image of the 1-P(superscript k-cyclic code is a distance-invariant quasi-cyclic code.

文章引入了Z下标 P(上标 k+1码和Z(下标 P^2)码之间的等距同构φ(k≥1)；利用φ把Gray映射φ：Z(上标 n 下标 4)→F(上标 2n 下标 2)推广为φ：；而且利用φ，负循环码概念被推广到Z下标 P(上标 k+1码，得到了1-P(上标 k-循环码；依据等距同构φ，给出了这些码的表示；也证明了1-P(上标 k-循环码在推广的Gray映射下的像是距离不变的准循环码。

We doodlers, fidgeters and whisperers always get the same jokey, passive-aggressive line from the authority figure at the front of the room:"I'm sorry, are we bothering you?" How droll.

我们这些涂鸦的人，搞小动作的人和爱嘀咕的人总是能得到站在房间前面的权威人士不变的滑稽、被动性攻击的话语："对不起，我们烦到你们了吗？"

Given two bridge-builders, a man and a woman, given a certain bridge to be built, and given as always the unchangeable laws of mechanics in accordance with which this special bridge and all other bridges must be built, it is simply inconceivable that the preliminary instruction given to the two bridge-builders should differ in quantity, quality, or method of presentation because while the bridge is building one will wear knickerbockers and the other a rainy-day skirt.

假定分别有男女两位桥梁建造者，要去建造指定的一座桥，在建造这一独特的桥及其它一般的桥的力学规律总是不变的情况下，简直不可想象，男女建造者所受的基本教育应有所不同；更不可想象，只是因为在施工时，一个穿灯笼裤，另一个穿防雨裙，而必须让他们在质量、数量及教学方法上接受不同的教育。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐