频率

Based on Wavelet Packet Analysis and Smoothed Pseudo Wigner-Ville Distribution, the experiment data is time-frequency analyzed.

结果表明：该等离子体声波强度随激光能量的增大而增大；频率范围在0-150KHz，在频率为25KHz附近有一峰值；且频率范围和峰值位置基本不随作用激光能量以及靶材料的改变而改变。

The FLL+ features digital frequency locked loop hardware that, in conjunction with a digital modulator, stabilizes the DCO frequency to a programmable multiple of the watch crystal frequency.

FLL+以数字式频率，与一个数字式调制器一道，稳定DCO频率对表面皿频率的一个可编程序的倍数的被锁的圈硬件为特色。

By parameter(tower total height, shell thickness, meridional curvature) analysis of cooling-tower natural frequency, we find that, the basic natural frequency of cooling tower is sensitive to the top meridional curvature, an approximate formula is proposed based on the parameters, which can estimate the basic natural frequency of cooling tower.

通过对冷却塔自振频率的参数分析，如塔体整高、塔壳厚度、子午线曲率等，发现基础频率对上部子午线曲率较为敏感，并给出了用于估算大型双曲冷却塔基础频率的三参数公式。

According to the applicable standards, there is only the requirement on the vertical bending vibration frequency of the carbody to be higher than 10Hz, while there is none against the frequency of transverse bending vibration and the carbody torsion vibration around the longitudinal axis.

根据有关标准，只要求车体的垂向弯曲振动频率大于10Hz，对侧墙横向弯曲振动频率、车体绕纵向轴扭转振动频率没有具体要求，因此在进行车体模态分析时，把顶盖看成设备，而不必考虑顶盖结构的影响。

Adjust the pressure of the impact system steplessly, the strike energy of the hammer will also shift steplessly. When the pressure is higher, the strike energy is higher. When the pressure is lower, the strike energy is lower. Adjust the oil flow of supply pump steplessly, the strike frequency will also shift steplessly. When the flow is more, the strike frequency is higher. When the flow is less, the strike frequency is lower.

从而可通过无级调节控制冲击系统的压力，无级调节控制冲击器的冲击能，压力高时冲击能大，压力低时冲击能小；通过无级调节控制油泵供给冲击系统的流量，无级调节控制冲击器的冲击频率，流量大时冲击频率高，流量小时冲击频率低。

Background— The INTRINSIC R (Inhibition of Unnecessary R Pacing with ASH in ICDs) study tested the hypothesis that dual-chamber rate-responsie with atrioentricular search hysteresis 60-130 programming is not inferior to single-chamber–40 programming in an implantable cardioerter defibrillator with respect to all-cause mortality and heart failure hospitalizations using an equialence margin of 5%.

背景： INTRINSIC R（ICD非必要右室起搏及房室搜索延迟）研究证实用5%的等效界值计算，就全因死亡率和心衰恶化住院而言，ICD双腔起搏频率应答模式加上房室搜索延迟模式，频率60~130 bpm，不劣于单独心室节律支持模式，频率40 bpm。

Its final target is to fully digitize the analogue receiver. The all digital receiver not just means digitizing every unit of the analogue receiver, but is a new receiver architecture. The two outstanding characters of this new architecture is: 1 It uses a high stable oscillator to generate a fixed frequency source. And both the sample signal and the local carrier required are obtained from it. 2 Once the received signal has been sampled by a high speed A/D converter, some digital signal processing algorithms will be used to realize all further processes, such as digital down-converting, match filtering, symbol timing, channel equalizing, carrier synchronizing, demodulating and decoding.

全数字接收机并不是简单地将传统的模拟接收机中所有的部件数字化的结果，而是一种全新的接收机体系结构，这种新的体系结构具有两个最为突出的特点：1）采用高稳定度晶体振荡器产生一个固定的本地频率源，接收机中所需的采样时钟信号和本地载波均从这一固定频率源得到；2）接收信号一旦经过高速模数转换后，余下的工作如频率变换、匹配滤波、定时同步、信道均衡、载波同步、符号解调、判决与译码等全部由数字信号处理算法来实现。

This paper puts forward the method of using the vibrating isolation ring to reduce noise ,and advances the definite principle of the rigidity of the vibrating isolation ring and calculation formula.

提出了用隔振环来降低振动筛噪声的方法，以及隔振环刚度的确定原则和计算公式。分析了安装隔振环后，对振动筛固有频率影响不大，可保证工作频率是最高固有频率的两倍以上，可保证振幅不低于原振幅的98%，基本上不降低工作效率。

Results indicate that the waves with certain frequencies in the waveguide can be downloaded into the cavity when resonance coupling occur and different frequencies are downloaded to cavities with different structures.

而具有特定本征共振频率的光子晶体微腔可将在其附近波导中传播的相应频率成份的光下载到微腔中，不同结构的腔可以&下载&不同频率成份的波。

Keyboard function set through waveform type,frequency,amplitude,duty cycle,and other parameters of a signal to the microprocessor 89C51 control,MAX038 generated by the various signals,In this process,four-channel signal through D/A converters have simulated voltage and current,It transported up through the analog signal amplification,it enters the frequency MAX038 coarse-IIN,fine-tuning FADJ end,the duty cycle control-DADJ. In its COSC port received a three relays and oscillation frequency capacitance as a choice.

通过键盘设定函数波形种类、频率、幅度、占空比等参数的一个信号进入单片机89C51控制，由MAX038产生各种波形信号，在此过程中信号通过四通道D/A转换器产生模拟电压和电流，它再通过运放将模拟的信号放大，它进入MAX038的频率粗调端IIN、微调端FADJ、占空比控制端DADJ、在它的COSC端口接一个继电器和三个振荡电容作为频率选择。

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