余弦

We derive the addition formulas for sine and cosine from the arithmetic of complex numbers.

用复数算术推导了正弦，余弦的加法公式。

We derive the addition formulas for sine and co sine from the arithmetic of complex numbers.

用复数算术推导了正弦，余弦的加法公式。

A mathematical relation model between liquor near infrared spectrum and liquor alcoholicity was established by use of the combination of discrete cosine transformation and BP neural networks, which was a new approach for rapid liquor alcoholicity determination.

采用近红外光谱的离散余弦变换和BP神经网络相结合，建立了白酒近红外光谱与其酒精度之间的数学关系模型，为快速检测白酒的酒精度提供了一种新的方法。

This experiment counts based on the direct digital frequencysynthesis the basic principle, fully II and hardware LT - IV testedthe box using ALtera Corporation's FPGA chip FLEX10 in softwareMaxplus in the platform to complete the DDS system design, hasdesigned a frequency and the phase may control has the sine and thecosine output direct numeral frequency synthesizer, was allowedto control and to observe the profile through the downloading boardand the Oscilloscope , completed in the enhancement request hascontrolled the frequency and the phase through the downloading boardon pressed key, as well as many kinds of profiles, includingsquare-wave, saw-tooth wave, triangle wave and cosine wave choiceoutput, In addition on digital tube dynamic demonstration productionprofile frequency, and produces the tbl document from the simulationprofile, simultaneously draws the profile using the matlab higherorder language.

帮忙翻译一下，谢谢本实验基于直接数字频率合成计的基本原理，充分利用ALtera公司的FPGA芯片FLEX10在软件MaxplusⅡ和硬件LT—IV实验箱的平台上完成了DDS系统的设计，设计了一个频率和相位均可控制的具有正弦和余弦输出的直接数字频率合成器，通过下载板和示波器可以控制和观察波形，在提高要求中完成了通过下载板上的按键来控制频率和相位，以及多种波形，包括方波、锯齿波、三角波和余弦波的选择输出，此外在数码管上动态显示生成的波形频率，并且从仿真波形中生成tbl文件，同时利用matlab高级语言画出波形。

This experiment counts based on the direct digital oscilloscope frequencysynthesis the basic principle, fully II and hardware LT - IV testedthe box using ALtera Corporation's FPGA chip FLEX10 in softwareMaxplus in the platform to complete the DDS system design, hasdesigned a frequency and the phase may control has the sine and thecosine output direct numeral frequency synthesizer, was allowedto control and to observe the profile through the downloading boardand the oscilloscope, completed in the enhancement request hascontrolled the frequency and the phase through the downloading boardon pressed key, as well as many kinds of profiles, includingsquare-wave, saw-tooth wave, triangle wave and cosine wave choiceoutput, In addition on digital oscilloscope tube dynamic demonstration productionprofile frequency, and produces the tbl document from the simulationprofile, simultaneously draws the profile using the matlab higherorder language.

帮忙翻译一下，谢谢本实验基于直接数字频率合成计的基本原理，充分利用ALtera公司的FPGA芯片FLEX10在软件MaxplusⅡ和硬件LT—IV实验箱的平台上完成了DDS系统的设计，设计了一个频率和相位均可控制的具有正弦和余弦输出的直接数字频率合成器，通过下载板和示波器可以控制和观察波形，在提高要求中完成了通过下载板上的按键来控制频率和相位，以及多种波形，包括方波、锯齿波、三角波和余弦波的选择输出，此外在数码管上动态显示生成的波形频率，并且从仿真波形中生成tbl文件，同时利用matlab高级语言画出波形。

To complete the DDS system design, hasdesigned a frequency and the phase may control has the sine and thecosine output direct numeral frequency synthesizer, was allowedto control and to observe the profile through the downloading boardand the oscilloscope, completed in the enhancement request hascontrolled the frequency and the phase through the downloading boardon pressed key, as well as many kinds of profiles, includingsquare-wave, saw-tooth wave, triangle wave and cosine wave choiceoutput, In addition on digital tube dynamic demonstration productionprofile frequency, and produces the tbl document from the simulationprofile, simultaneously draws the profile using the matlab higherorder language.

本实验基于直接数字频率合成计的基本原理，充分利用ALtera公司的FPGA芯片FLEX10在软件MaxplusⅡ和硬件LT—IV实验箱的平台上完成了DDS系统的设计，设计了一个频率和相位均可控制的具有正弦和余弦输出的直接数字频率合成器，通过下载板和示波器可以控制和观察波形，在提高要求中完成了通过下载板上的按键来控制频率和相位，以及多种波形，包括方波、锯齿波、三角波和余弦波的选择输出，此外在数码管上动态显示生成的波形频率，并且从仿真波形中生成tbl文件，同时利用matlab高级语言画出波形。

This experiment counts based on the direct digital frequencysynthesis the basic principle, fully II and hardware LT - IV testedthe box using ALtera Corporation's FPGA chip FLEX10 in softwareMaxplus in the platform to complete the DDS system design, hasdesigned a frequency and the phase may control has the sine and thecosine output direct numeral frequency synthesizer, was allowedto control and to observe the profile through the downloading boardand the oscilloscope, completed in the enhancement request hascontrolled the frequency and the phase through the downloading boardon pressed key, as well as many kinds of profiles, includingsquare-wave, saw-tooth wave, triangle wave and cosine wave choiceoutput, In addition on digital tube dynamic demonstration productionprofile frequency, and produces the tbl document from the simulationprofile, simultaneously draws the profile using the matlab higherorder language.

涂层测厚仪-帮忙翻译一下，谢谢涂层测厚仪-帮忙翻译一下，谢谢帮忙翻译一下，谢谢本实验基于直接数字频率合成计的基本原理，充分利用ALtera公司的FPGA芯片FLEX10在软件MaxplusⅡ和硬件LT—IV实验箱的平台上完成了DDS系统的设计，设计了一个频率和相位均可控制的具有正弦和余弦输出的直接数字频率合成器，通过下载板和示波器可以控制和观察波形，在提高要求中完成了通过下载板上的按键来控制频率和相位，以及多种波形，包括方波、锯齿波、三角波和余弦波的选择输出，此外在数码管上动态显示生成的波形频率，并且从仿真波形中生成tbl文件，同时利用matlab高级语言画出波形。

Finally, the designed sine and cosine sensor are applied on the simulated semi-infinite roof beam to compare their measurement results with the traditional piezoelectric acceleration sensor. The experiment results show that they are applicable and feasible.

最后，在模拟半无限长的钢梁上，利用压电加速度传感器与所设计的正弦形状和余弦形状传感器测量进行比较，实验结果表明，设计制作的正弦形状和余弦形状传感器是适用可行的。

The constraints of oversampled cosine modulated filter banks with perfect reconstruction are deduced in this paper and then we propose an iterative method for designing the prototype filter.

接下来我们推导了过采样余弦调制滤波器组的完全重构条件，提出了一种迭代算法设计完全重构的过采样余弦调制滤波器组。

It is shown that the M×N ChG beams in turbulent undergo three stages of evolution with increasing propagation distance,and turbulence accelerates the evolution of three stages.The turbulence results in a spreading and degradation of the maximum intensity in the far field.But β-parameter decreases with increasing beam numbers M,separate distances xd and beam parameter δ.And there exists optimal values of xd and δ,and SR of the corresponding M×N ChG beams reaches its maximum.

研究表明：在湍流大气中，双曲余弦高斯列阵光束的传输将经历三个阶段的变化，并且湍流使得光束传输经历三阶段的进程加快；湍流导致双曲余弦高斯列阵光束扩展、最大峰值光强下降，但是，β参量随光束数目M、相邻子光束间距xd和光束参量δ的增加而减少，即光束扩展受湍流的影响减小；并且，存在最佳xd和δ值使得Strehl比取得极大值。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。