I hf electrothermal equipment production company , be applied to smelting . qian welding . heat treatment . forging hf hanguan . large direct current generator mechanics 我公司生产中高频电热设备,可应用于熔炼.钎焊.热处理.锻造高频焊管.大型直流电动机调速等
Comparisons between the acoustic performances of the air cleaners with and without filter paper illustrated that the acoustic attenuation performance has been improved due to the existence of filter paper 通过比较不带滤纸和带有滤纸的空气滤清器的声学性能结果表明，滤纸的考虑与否对空滤器的中高频消声性能有很大影响。
This paper also discusses using computer graphic hardware to accelerate electromagnetic simulation computation . after integrating these parts , we develop an electromagnetic predication software system emx 根据本文中高频电磁估算方法理论，我们开发了一套电磁估算系统emx ，并完成其中的高频估算部分，通过对实验结果的对比。
Harada j , aoyagi m , suzuki t , et al . a study on the phase spectral analysis of middle latency response and 40 - hz event - related potential in central nervous system disorders j . acta otolaryngol ( stockh ) 1994 , suppl 511 : 34 吕建忠，唐小青，彭世春,等.听性脑干反应相位谱分析客观诊断中高频听力损失j .耳鼻咽喉-头颈外科， 1997 ， 4 : 131
The paper gives the capacity guideline on the foundation of the requirements of the high - frequency dc module in the power system , compares various dc topologies , selects the appropriate circuit topology for the dc - dc module , emphasized its detailed constructure , devised the main circuit , the control circuit , the power circuit , soft - start and protection . finally the required module comes into being and passes the verification 本文根据对电力系统的直流电源柜中高频dc - dc模块的具体要求制定其特性指标，通过对各种dc - dc拓扑结构进行分析比较，选择了合适的dc - dc模块的电路拓扑结构，并对此拓扑结构的电路进行了详细的分，设计了主电路、控制电路、电源电路、软启动和保护等，最后实现了模块的制作，通过了测试。
The research contents of this paper includes as follows : firstly , design a new type reader based on ti s6700 reader ic and try to enhance the reading distance through adding power amplifier ; secondly , adopt the idea of gpio simulation to produce spi timings to drive s6700 . secondly , overcome the shortcoming of general mcu spi port ; thirdly , design the rs232 / rs485 full duplex conversion module , mmi interface in the system ; fourthly , analyze the rfid system communication protocol iso15693 and find out the working processes and realization of the instruction ; lastly , discuss the communication safety and accidental factors including the checkout and collision design , illustrate the realization of crc and anti - collision arithmetic theory 本论文的主要研究内容包括: (一)设计基于s6700阅读器芯片的新型阅读器,通过使用对中高频阅读器外加功率放大模块的方法,实现较远距离通信。 (二)采用单片机通用口三线模拟的方法模拟通用spi口时序,克服其不可位操作的缺点,实现对s6700的驱动。 (三)在rfid系统中集成设计了rs232 / rs485通讯模块、液晶显示模块等,着重说明了其软硬件实现方法。
An asymmetric digital watermarking algorithm based on dwt is presented in this paper . the watermark was embedded into the middle _ high coefficients based on spread spectrum modulation scheme , and the intensity of embedding could be accommodated adaptively , so the digital watermarking system has good perceptual invisibility and robustness 该算法利用私钥把水印嵌入到小波分解后的中高频系数中,提高了水印系统的不可视性,水印嵌入过程中可以自适应的调节嵌入强度,同时引入了扩频的概念,增强了水印系统的鲁棒性。
This proof following enterprise already through the authentication , and has set up a file in the dongguan 114 nets industry and commerce enterprise database , inquires the more detailed enterprise material , please dial the dongguan enterprise information desk 96060 ( artificially ) 9686810114 billion ( to be automatic ) , this enterprise numbers for 50493 兹证明晨昕中高频设备有限公司广东办事处已通过认证，并已在东莞114网工商企业数据库中备案，查询更详细的企业资料，请拨东莞企业查询台96060 （人工） 9686810114 （自动） ，该企业编号为50493 。
We present two different frameworks to analyzing the high frequency time series : first , regularly spaced sampled observations , which is sampled with interval of one hour , one minute even one second ; secondly , the irregularly spaced data , such as transaction by transaction data 。 the main work and innovations of the dissertation include : 1 . through empirical research of high - frequency time series of shanghai composite index , the paper researches the different statistical properties on different frequency 高频时间序列的分析与建模是金融计量学的一个全新研究领域。金融市场中高频时间序列分为两类:一类是采样间隔相等的数据,比如一小时、十分钟、五分钟、甚至是以秒为单位采集的按时间先后排列的等时间间隔的数据;另一类是指对交易过程实时采集的数据,也就是每笔交易的数据(显然是不等间隔的数据) 。
Because the high resolution on high frequency of wavelet package meets the feature of fingerprint containing abundant high frequency , we filtered the fingerprint preliminarily by means of wavelet package . while designing orientation filter , we introduced the square - circle transform to rotate filter , thus we reduced computing complexity and avoided imported errors 具体地，结合指纹图像中高频丰富的特点，以及小波包高频分辨率高的分析特性，选用小波包对指纹图像进行初滤波；在设计方向滤波器时，对滤波器的旋转引入了方?圆变换的方法，进而减少了计算的复杂度，同时避免引入误差。
