共查询到11条相似文献,搜索用时 62 毫秒
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《声学学报:英文版》2014,(5)
语音线性预测分析算法在噪声环境下性能会急剧恶化,针对这一问题,提出一种改进的噪声鲁棒稀疏线性预测算法。首先采用学生t分布对具有稀疏性的语音线性预测残差建模,并显式考虑加性噪声的影响以提高模型鲁棒性,从而构建完整的概率模型。然后采用变分贝叶斯方法推导模型参数的近似后验分布,最终实现噪声鲁棒的稀疏线性预测参数估计。实验结果表明,与传统算法以及近几年提出的基于l_1范数优化的稀疏线性预测算法相比,该算法在多项指标上具有优势,对环境噪声具有更好的鲁棒性,并且谱失真度更小,因而能够有效提高噪声环境下的语音质量。 相似文献
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The performance of linear prediction analysis of speech deteriorates rapidly under noisy environments.To tackle this issue,an improved noise-robust sparse linear prediction algorithm is proposed.First,the linear prediction residual of speech is modeled as Student-t distribution,and the additive noise is incorporated explicitly to increase the robustness,thus a probabilistic model for sparse linear prediction of speech is built.Furthermore,variational Bayesian inference is utilized to approximate the intractable posterior distributions of the model parameters,and then the optimal linear prediction parameters are estimated robustly.The experimental results demonstrate the advantage of the developed algorithm in terms of several different metrics compared with the traditional algorithm and the l1 norm minimization based sparse linear prediction algorithm proposed in recent years.Finally it draws to a conclusion that the proposed algorithm is more robust to noise and is able to increase the speech quality in applications. 相似文献
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Remez RE Dubowski KR Davids ML Thomas EF Paddu NU Grossman YS Moskalenko M 《The Journal of the Acoustical Society of America》2011,130(4):2173-2178
Linear prediction is a widely available technique for analyzing acoustic properties of speech, although this method is known to be error-prone. New tests assessed the adequacy of linear prediction estimates by using this method to derive synthesis parameters and testing the intelligibility of the synthetic speech that results. Matched sets of sine-wave sentences were created, one set using uncorrected linear prediction estimates of natural sentences, the other using estimates made by hand. Phoneme restrictions imposed on linguistic properties allowed comparisons between continuous and intermittent voicing, oral or nasal and fricative manner, and unrestricted phonemic variation. Intelligibility tests revealed uniformly good performance with sentences created by hand-estimation and a minimal decrease in intelligibility with estimation by linear prediction due to manner variation with continuous voicing. Poorer performance was observed when linear prediction estimates were used to produce synthetic versions of phonemically unrestricted sentences, but no similar decline was observed with synthetic sentences produced by hand estimation. The results show a substantial intelligibility cost of reliance on uncorrected linear prediction estimates when phonemic variation approaches natural incidence. 相似文献
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A. V. Gerasimov O. A. Morozov E. A. Soldatov V. R. Fidelman 《Radiophysics and Quantum Electronics》2006,49(7):535-539
Ensuring the acceptable acoustic coding of a signal under the conditions of noise interference is an important problem of
recognizing speech signals. The result of calculating acoustic characteristics by the existing algorithms strongly depends
on the signal-to-noise ratio. To solve the problem related to ensuring robust acoustic coding, we propose an algorithm for
obtaining cepstral coefficients on the basis of the method of modified linear prediction. The algorithm is aimed at the specific
features of the vocalized speech signals with a pronounced formant structure including the case of wideband additive interference.
The algorithm stability as a function of the noise level is studied experimentally. The result is improved compared with the
well-known approaches.
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Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 7, pp. 593–598, July 2006. 相似文献
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蛋白质loop区的结构预测是理解蛋白质功能的重要一环,而长loop区的结构预测至今还是生物信息学中的难题.目前己经出现了多种loop结构的算法,其中LEAP是预测精度最高的算法之一,但它在长loop区初始主链构象采样上仍有较大的改进余地.本文中我们将蛋白质二级结构预测算法SPINE X与LEAP算法结合起来,构建了新的主链扭转角分布图(拉氏图),在主链初始构象采样中引入氨基酸在蛋白序列中的位置特异性信息,使得初始构象的采样更具针对性,对取自CASP10单链蛋白的loop测试集的分析表明,对长度为10,11,12个氨基酸的长loop区,改进后算法都比原始LEAP算法的预测精度有显著提升.这种引入氨基酸位置特异性从而提高预测精度的思路有望进一步推广至loop结构预测的其他算法. 相似文献
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In recent years, there has been a concerted effort to reduce the MR scan time. Signal processing research aims at reducing the scan time by acquiring less K-space data. The image is reconstructed from the subsampled K-space data by employing compressed sensing (CS)-based reconstruction techniques. In this article, we propose an alternative approach to CS-based reconstruction. The proposed approach exploits the rank deficiency of the MR images to reconstruct the image. This requires minimizing the rank of the image matrix subject to data constraints, which is unfortunately a nondeterministic polynomial time (NP) hard problem. Therefore we propose to replace the NP hard rank minimization problem by its nonconvex surrogate — Schatten p-norm minimization. The same approach can be used for denoising MR images as well.Since there is no algorithm to solve the Schatten p-norm minimization problem, we derive an efficient first-order algorithm. Experiments on MR brain scans show that the reconstruction and denoising accuracy from our method is at par with that of CS-based methods. Our proposed method is considerably faster than CS-based methods. 相似文献
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Louis Block James Keesling Shihai Li Kevin Peterson 《Journal of statistical physics》1989,55(5-6):929-939
A new algorithm is presented for computing the topological entropy of a unimodal map of the interval. The accuracy of the algorithm is discussed and some graphs of the topological entropy which are obtained using the algorithm are displayed. 相似文献
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Based on the Bayesian information criterion, this paper proposes the
improved local linear prediction method to predict chaotic time
series. This method uses spatial correlation and temporal
correlation simultaneously. Simulation results show that the
improved local linear prediction method can effectively make
multi-step and one-step prediction of chaotic time series and the
multi-step prediction performance and one-step prediction accuracy
of the improved local linear prediction method are superior to those
of the traditional local linear prediction method. 相似文献