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针对最小值控制递归平均(Minima Controlled Recursive Averaging,MCRA)算法不能快速跟踪突变噪声的问题,提出了一种基于频谱排序和筛选的突变噪声快速估计方法。该方法在MCRA算法的基础上对带噪语音的功率谱进行排序,筛选出不含语音信号的频点来估计噪声的平均功率谱;当检测到噪声突变时,对当前的平滑参数和状态变量进行校正。仿真结果表明,该方法可以将突变噪声的跟踪时间缩短90%以上;用于语音降噪处理时,音质可以提升约0.4分。该方法具有一定的工程应用价值。 相似文献
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胡岩松 《环球市场信息导报》2017,(44):95-95
本文所采用的一种SCHMM/ANN模型,通过在ubuntu14.04环境下搭建了用于语音识别的Kaldi系统,编写了两种模型的训练及识别脚本。利用开源的语音库THCHS-30对两种模型进行了验证,得到了无噪声环境下两者的语音识别率。对两种模型进行了抗噪性能的分析,测试语音中加入高斯白噪声对两种模型进行实验测试。最后通过实验数据说明了混合模型在噪声环境下能够取得较好的识别效果,并通过实验证明了改进的端点检测算法在两种模型的语音识别当中都是有效的。 相似文献
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针对低信噪比超宽带信号的消噪问题,提出一种改进的基于经验模式分解(EMD)的
消噪算法。该算法首先对含噪信号进行EMD分解,得到多个固有模态函数(IMF)分量,然后
选取高阶IMF重构原信号,达到消噪的目的。针对对UWB信号的IMF重构过程中阶数阈值难以
确定的问题,通过数值仿真的方法,得到信号分量和噪声分量在不同阶IMF上的能量分布特
性;在对所得特性进行分析的基础上,设计了一种数据自适应的阶数阈值选取算法,解决了
EMD消噪中的阶数阈值选取问题。仿真结果表明,EMD消噪算法能够在较低信噪比下提供平均
10 dB的信噪比增益,可以有效地对超宽带信号进行消噪。 相似文献
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在语音加密通信过程中,接收方需要通过信号同步来实现精确的解密并恢复出语音信号,而现有方法精确度低且运算量大。为了解决端到端语音加密、解密过程中的同步问题,设计了一种新的基于线性调频信号的同步信号结构。该同步信号是基于带宽经过筛选的线性调频信号产生,避免了因为添加同步信号而使带宽扩展的问题。同步信号结构由两种不同长度的线性调频信号组合而成,不同的组合形式又会产生不同的同步效果。这种结构设计大大提高了同步的精确度和减少了同步运算量。理论和实验证明:该方法可以实现对接收信号帧起始位置进行精确地定位;不会展宽和影响语音信号的频谱;可以透过语音编解码器传输;具有一定的抗噪声性能;运算量比原始结构的同步信号大大减少。 相似文献
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扩频系统接收机模拟中频信号的量化会带来信噪比损失,在一定程度上影响扩频系统的抗干扰性。为提升接收机输入端量化信噪比,针对服从高斯分布的噪声且低信噪比的接收机模拟中频信号,提出一种自适应功率的模拟中频信号的“最佳失真度量化方法”。首先分析数模转换器的特性划定量化门限,然后依照输入信号的统计特性,设计出最佳功率的计算方法,并提出新的评价指标“载噪比”,可以在捕获前预先衡量量化损失。通过仿真计算了“最佳失真度量化方法”的载噪比,并与 “传统法”进行对比。实现结果表明,所提方法的载噪比相对于“传统法”的均值提升0.27 dBHz。 相似文献
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本文介绍的语音检测器以DSP芯片TMS320VC5402为核心,对短波电台接收到的信号进行分析和处理。数字语音信号采用串行输入/输出方式,语音检测算法则采用对语音信号进行降噪处理后,再进行短时平均幅度差和短时能量计算的方法。该语音检测器的电路简洁小巧,语音检测准确度高。 相似文献
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Holding percent of train media resources across China based on "Time Cube" on the Intermedia Recommendation Introduction Meeting on December HTC announced its high-profile strategy of tour marketing tapping the immeasurable potentials on the train. Meanwhile HTC officially launched its brand new product Olympic Train on the meeting providing a fabulous platform for all the brands that are prepared to do a smart marketing on the occasion of Olympic Games.…… 《中国对外贸易(英文版)》2008,(1):58
Holding 88 percent of train media resources across China, based on "Time Cube", on the 2008 Intermedia Recommendation and Introduction Meeting on December 19, 2007, HTC announced its high-profile strategy of tour marketing and tapping the immeasurable potentials on the train. Meanwhile, HTC officially launched its brand new product Olympic Train on the meeting, providing a fabulous platform for all the brands that are prepared to do a smart marketing on the occasion of 2008 Olympic Games. 相似文献
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Audrey Guo 《中国对外贸易(英文版)》2008,(1)
In the end of 2007, Air China Limited (hereinafter "Air China") and Shanghai Airlines, formally joined Star Alliance at a ceremony held in the new Terminal Three at Beijing Capital International Airport. With the addition of the two Chinese airlines, Star Alliance now has 19 member carriers operating 17,000 daily flights to 897 destinations in 160 countries. 相似文献
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Bai Yifeng 《中国对外贸易(英文版)》2008,(1):59-59
Under the guidance of the theme slogan of the 29th Olympic Games - One World One Dream, with dream, love and dedication as its theme, the 2008 Music Grand Ceremony & 1000 People Charity Concert on 100 days cotmtdown to Paralympic Gamesis officiaily launched on December 22, 2007. The 2008 Music Grand Ceremony is sponsored by China Disabled Persons' Federation, and co-hosted by National Paralympic Committee of China, 相似文献
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《中国对外贸易(英文版)》2008,(6):45-45
With its headquarters in the historic city of Yangzhou,Jiangsu Muyang Group Co.,Ltd has since its founding in 1967 grown into a well-known group corporation whose activities cover research & development,project design,manufacturing,installation and services in a multitude of industries including feed machinery and engineering,storage engineering,grain machinery and engineering,environmental protection,conveying equipment and automatic control systems. 相似文献
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Chun Yi 《中国对外贸易(英文版)》2008,(1):13
Aseries of events that occurred in October 2007, are rewriting the history of China's energy industry: November 3 an Energy Law Committee asked the public for suggestions on improvements; forty top experts came together to form the National Energy Expert Advisory Committee on November 6; and the National Oil Reserve Center (NORC)became the nerve centre of oil reserves on November 18. Yet, behind the progress of these recent activities remains the fact that international oil prices still hover around a very high price of US$ 90/barrel, and China's oil imports are close to accounting for half of its total oil reserves. 相似文献
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China Harbor Ten People elected the entrepreneurs who contributed a lot to port economy enterprises this year trough their talent management.These ten people embody their social responsibility professional skills creative ability and charming personality.Bearing full confidence in China's port economy the port entrepreneurs are brave enough to explore a brand new area so as to promote harbor economic development.…… 《中国对外贸易(英文版)》2008,(6):46-46
2007 China Harbor Ten People elected the entrepreneurs who contributed a lot to port economy and enterprises this year trough their talent management.These ten people embody their social responsibility,professional skills,creative ability,and charming personality.Bearing full confidence in China's port economy,the port entrepreneurs are brave enough to explore a brand new area,so as to promote harbor economic development. At the very beginning of 2008,China Shipping Website,Dalian Maritime University,and China Port and Shipping In- stitute jointly select the 2007 China Harbor Ten People,demonstrate port entrepreneurs' stunning minds,disclose their secrets to success,and providing abundant experiences to others in harbor development.The top ten people are various excellence during the ups and downs harbor development. 相似文献
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Guo Yan 《中国对外贸易(英文版)》2008,(10):22-23
Since the normalization of the diplomatic ties between China and ) Japan, the bilateral economic relations have deepened continually. According to the statistic of Japan, China passed U.S. to become Japan's top trade partner as well as is the second largest export market for Japan and is the largest import resource for Japan. Japan companies such as Mitsui, Sumitomo, Sony and Panasonic, have set the subsidiaries in China and explored their scales. This year 2008 marks the 30th anniversary of the signing of the ChinaJapan Treaty of Peace and Friendship. 相似文献
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《中国对外贸易(英文版)》2008,(12)
China's textile and apparel industry suffered an unprecedented cold market for exports in the first quarter this year,the result of a few factors including: the appreciating RMB, decreasing export rebate rate,expanding influence of the U.S. subprime crisis, increasing costs of production and rising labor cost. 相似文献
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The central bank of China has raised her deposit rate for 6 times,and deposit reserve rate for 16 times,since last year up to now,which resulted to a great suffer to those small and medium sized enterprises in finance collection.30 percent of China s small and medium sized enterprises have to be closed down, and 60 percent of them are because of finance problem.How to gather the fund is the biggest obstacle for China's enterprises to grow. 相似文献
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《中国对外贸易(英文版)》2008,(9)
Contribution to the society
Zhang Hao owns great opportunity to store intelligence and knowledge, in her early year.Zhang Hao was graduated from Economic Management Department of People's University in 1983 and later finished her study in Advanced Training Program of CEO of Chinese Direct Selling Enterprises in Peking University. 相似文献