麦克风特性研究的教学实验系统搭建

为了研究不同声场条件下麦克风的特性,以满足生物医学工程声学实验教学的需求,研制了一套基于USB声卡的声学教学实验系统。该系统包含麦克风模块、硬件电路模块、USB声卡模块和终端计算机,以符合助听器和电子耳蜗等小型设备的前端信号采集的参数指标和尺寸要求。所搭建的系统为教学实验提供了一套声学测试平台,用于测试自由声场和放置头部模型等不同声场条件下的麦克风的特性,以及进一步通过麦克风阵列所进行的语音增强的系列研究。该开放式实验系统的搭建有利于培养学生对声学基本实验操作能力和对学生创新性思维的发掘。     

教学扩声的理论与实践探索

教学扩声是课堂教学的重要组成部分,但传统的手持有线麦克风和佩戴无线麦克风等扩声方式已不能满足当前的教学需求。基于此,文章首先从教学扩声系统的发展历程入手,对教学扩声中的声音响度和声像一致性进行分析研究,指出了手持有线麦克风和佩戴无线麦克风等传统扩声方式存在的问题。接着,文章结合应用实践详细阐述了吊麦扩声的优势,从反馈抑制算法和回声消除算法两个方面对吊麦扩声的关键技术难点进行分析,从教学实际应用的角度对吊麦扩声做了趋势展望,以期为学校后续教学扩声的研究、建设与应用提供参考。     

视频、音频教学素材导入电脑的方法

本文介绍在Windows 9X环境下的视频、音频教学资源导入电脑的方法. 一、如何进行电脑录音? 方法一:利用Windows自带的"录音机"程序录音. 1.首先将麦克风的导线插入计算机声卡的"MIC"的端口中,打开音箱或戴上耳机,调试麦克风,确保麦克风正常工作.     

麦克风阵列声源定位的实验设计与实现

基于麦克风阵列的声源定位技术,可以应用在智能交互、智能家电、视频会议、语音识别等领域。该文设计了一个使用麦克风阵列进行声源定位的综合型实验项目,并应用到本科生开放创新实验中。实验充分利用多个麦克风阵元间的空域和时域信息,采用时延估计算法对不同阵元波达时间延迟进行估计。通过构建阵元几何关系并利用阵元信号的时延,获得了在噪声环境下较好的声源定位效果。教学实践表明,该实验项目可以较好地拓展学生的信号处理能力,有利于对学生创新设计能力和解决复杂问题能力的培养。     

支持双麦克风的蓝牙无线接收器及在教学中的应用

针对教学互动环节中需要师生同时使用麦克风的需求,设计了一种支持双麦克风的蓝牙无线接收器。该接收器可同时采集两个蓝牙麦克风的声音并放大,并直接驱动多媒体教室已有的音箱设备,具有声音清晰、安装简便的特点。     

机器人声源定位系统实验设计与实现

基于嵌入式系统完成了机器人声源定位系统的设计,设计了麦克风阵列和采集电路,并基于互相关函数估计时延法的机器人声源定位算法,实现了机器人声源定位;设计并实现了机器人声源定位演示实验和机器人声源定位半开放实验,实验效果达到预期实验设计的目标。     

碳粒麦克风性质探究与制作

了解碳粒麦克风的结构、工作原理和各元件性质.探究什么原因使得碳粒麦克风从被广泛运用到被淘汰.取核心部件建立模型,制作简易碳粒麦克风,尝试重现这一装置,并重点研究对碳粒麦克风性质影响最大的参量——碳粉.     

QA答疑室

Q:小博士,最近我只要打开麦克风,音箱就会发出很大的杂音,用Windows自带的录音机录音时麦克风也没有反应了,请问问题出在哪里?(小意思)     

老师,请摘下你的麦克风

有这样一个真实的故事:一位年轻的女教师,做了喉部囊肿切除术后,借助麦克风仍坚持给学生上课,她的毅力深深地感动了我。然而,麦克风、扩音器现如今似乎也成了一些教师的装备,大量地进入课堂。最近,一次     

麦克风阵列语音增强的二维FIR滤波器设计

当不能准确估计声源个数以及波达方向时,基于传统波束形成的语音增强的性能大为降低。根据手持通信设备的特点,提出一种利用麦克风阵列进行噪声及干扰抑制的方法。该方法采用具有扇形结构通带的二维FIR滤波器,利用楔形过渡带,实现指定角度内宽带语音的波束形成,用来抑制期望主瓣外的噪声和干扰。仿真实验表明了该滤波器的有效性。     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…     

库克斯顿城堡

城堡, 是欧洲典型的建筑之一, 每个城堡都有一个美丽的传说或是一段历史。从本期开始, 我们将推出“城堡之旅”, 带各位读者去浏览、观赏欧洲各地的城堡, 开始一段文化与历史的旅途!     

胡主席在印度,我却在中国

Today, Sunday morning, I sit thinking and typing at my computer. My thoughts are in my homeland, India and my body is in China. The body is here and mind there for a good reason. Mr. Hu is president and I am resident and both are in each other's countries (what a difference the absence of one small letter makes!). Mr. Hu will return in a few days and I will stay on longer.