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紫外-可见光谱测定马尾松纸浆树脂中甘油三酯含量 总被引:5,自引:0,他引:5
用紫外光谱法测定马尾松TMP浆和酸性亚硫酸盐浆正己烷抽出物中甘油三酯的含量,探讨了三油酸甘油酯标准物与纸浆树脂的紫外吸光谱图特征与特征峰位置以及测试时间对吸光度值的影响。结果表明,在实验试剂用量范围内,三油酸甘油酯在412 nm的吸光度与浓度成线性关系,线性相关系数为0.971;吸光度随测试时间呈线性降低关系,相关系数为0.990。再现性实验回收率98%~104%,精确度1.27%~4.03%。利用该方法测定了纸浆与酶处理后纸浆抽提物中甘油三酯的含量,评价了酶处理纸浆降解甘油酯的效果。马尾松TMP与酸性亚硫酸盐浆中甘油三酯含量较高,约占总抽提物的50%。酶处理后TMP浆与酸性亚硫酸盐浆中甘油三酯降解率分别达到46.31%和35.55%。 相似文献
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Zeng Yumin Wu Zhenyang 《电子科学学刊(英文版)》2007,24(6):828-834
A novel text independent speaker identification system is proposed. In the proposed system, the 12-order perceptual linear predictive cepstrum and their delta coefficients in the span of five frames are extracted from the segmented speech based on the method of pitch synchronous analysis. The Fisher ratios of the original coefficients then be calculated, and the coefficients whose Fisher ratios are bigger are selected to form the 13-dimensional feature vectors of speaker. The Gaussian mixture model is used to model the speakers. The experimental results show that the identification accuracy of the proposed system is obviously better than that of the systems based on other conventional coefficients like the linear predictive cepstral coefficients and the Mel-frequency cepstral coefficients. 相似文献
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JongKuk Kim HernSoo Hahn Uei-Joong Yoon MyungJin Bae 《Wireless Personal Communications》2009,50(4):435-446
Speech synthesis can be classified into waveform coding, source coding, or hybrid coding by the synthesis method. Among these,
waveform coding is especially suitable for high-quality speech synthesis. However, synthesis techniques using syllable or
phoneme unit is not desirable since it fails to separate the excitation and the formant part to handle speech. Therefore,
there is a need for a pitch alteration method to apply in synthesis using waveform coding. This study proposes a pitch alteration
method that uses spectrum scaling after flattening the spectra by a sub-band linear approximation to minimize the spectrum
distortion. A comparison with LPC (Linear Predictive Coding), Cepstrum and lifter function is presented to show the better
performance of the proposed method. Estimation method seeks each of the distributions of the flattened signal and measures
the degree of the flattened spectrum Signal, which is normalized, so the highest point amounts to zero, and the distribution
of the signal, whose average is zero, is calculated. The results are presented by the spectrum distortion rate to estimate
the performance of the proposed method. The average spectrum distortion rate kept below the average 2.12%, showing the proposed
method’s superiority in comparison with the other existing approaches.
相似文献
MyungJin BaeEmail: |
98.
This paper proposes a voice synthesizer to convert a single speech to multiple speeches. Pitch is an important voice characteristic
of speech parameter and it is produced by the periodic vibration of the vocal-cords; the parameter most sensitive for human’s
auditory sense. So if you change the pitch of the voice with several different scaling rates, you can produce several different
voices at the same time with a voice. The Multiple-Speech Synthesizer will be used in diverse practical applications. The
cheer synthesizer that makes group voice from a single voice would be such an example. You could also use the system for a
troll toy, birthday song tracks, effect sounds in movies and plays, protection systems of houses, etc. Furthermore, the synthesizer
could be used to imitate the voice of famous entertainers or cartoon characters, such as the Mask-man.
相似文献
Myung Jin BaeEmail: |
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语音的基频(也称音高、基音周期或F0)及其变化规律是语音信号的一个重要特征,在语音情绪识别、声纹识别中有重要的应用。而语音基频的提取一直是语音信号处理中的难点,这也是语音基频特征未能广泛应用于语音识别等应用的重要原因,因此准确高效的提取音高在语音信号处理中能够有重要的意义。本文基于归一化自相关函数,结合倒频谱方法,提取了一种改进的基于归一化自相关的语音基频提取算法,实验证明该方法在基频提取中取得了较好的结果。 相似文献