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An improved algorithm for noise-robust sparse linear prediction of speech

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Chinese Journal of Acoustics 2015年第1期34卷 84-95页

作者： ZHOU Bin zou xia zhang xiongwei The 63rd Research Institute of PLA General Staff Headquarters PLA University of Science and Technology

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.

关键词： An improved algorithm for noise-robust sparse linear prediction of speech PESQ LP

Time-frequency mask estimation-based speech enhancement using deep encoder-decoder neural network

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Chinese Journal of Acoustics 2021年第1期40卷 141-154页

作者： SHI Wenhua zhang xiongwei zou xia SUN Meng LI Li REN Zhengbing Army Engineering University Nanjing 210007 Beijing Aeronautical Technology Research Center Nanjing 210028 First Military Representation Office of Air Force Equipment Department Changsha 410114

A time-frequency mask estimation using deep encoder-decoder neural network for speech enhancement is *** mask estimation is learned implicitly by the deep encoder-decoder neural network *** with the time-frequency representation of the noisy speech to learn the nonlinear mapping function between the noisy and target *** deep encoder-decoder neural network employs convolution and de-nonvolution *** convolution encoder makes use of the local perception characteristic of convolution network to model the typical structural features of noisy speech in the time-frequency *** features are extracted and the influence of background noise is *** the decoder end,the speech signal is reconstructed from the extracted speech features in the encoder end and the local details are recovered layer by ***,skip connections are introduced between homologous layers to circumvent the low level details losing problem induced by pooling and down-sampling *** are conducted on the TIMIT dataset and the results demonstrate that the proposed method can effectively suppress noise and recover the detailed information of speech.

关键词： decoder network neural

Effects of Squealer Geometry of Turbine Blade Tip on the Tip-Leakage Flow and Loss

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Journal of Thermal Science 2021年第4期30卷 1376-1387页

作者： ZENG Fei zhang Weihao WANG Yufan CAO xia zou Zhengping National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy&Power EngineeringBeihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China

The effective control of the tip-leakage flow and loss is of great significance to improve the aerodynamic performance of the *** this paper,the evolution mechanism of tip-leakage flow in a transonic high pressure turbine with a squealer tip is investigated with numerical simulation *** impacts of squealer geometric,such as the inclined pressure side rim and squealer rim width,on the vortex structure in the gap and tip-leakage loss are *** results show that the scraping vortex inside the cavity plays the role of aero-labyrinth seal,and forms interlocking sealing labyrinth structure with the rims on both sides,which has an effective sealing effect on the tip-leakage *** inclined pressure side squealer rim inhibits the development of the pressure side squealer corner vortex,which is beneficial to expand the influence range of the scraping vortex and enhance the sealing effect on the tip-leakage *** increase of the suction side squealer rim width reduces the effective flow area at the gap exit,which is conducive to reduction of the tip-leakage flow rate and tip-leakage ***,the increase of the pressure side squealer rim width strengthens the pressure side squealer corner vortex and limits the development space of the scraping vortex,causing the adverse effects on the control of tip-leakage flow.

关键词： turbine squealer tip tip-leakage flow squealer width tip-leakage loss

Adenomyosis uterine innervation in mice correlates to nerve growth factor expression,inflammation,and vascularization

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Neural Regeneration Research 2010年第1期5卷 15-20页

作者： Yan Li Shaofen zhang xian xia Shien zou Department of Gynaecology Obstetrics and Gynaecology H~spital of Fudan University Shanghai 200011 China

BACKGROUND： Studies have shown that abnormal innervation is an important factor impacting occurrence and development of pathological pain in endometriosis. OBJECTIVE： To observe uterine innervation of adenomyosis mice and to analyze the cause of innervation changes due to nerve growth factor （NGF） expression, inflammation, and vascularization. DESIGN, TIME AND SETTING： This randomized, controlled, animal experiment was performed at the Research Institute of Obstetrics and Gynecology Hospital, and Central Laboratory of Zhongshan Hospital, Fudan University from March to December 2008. MATERIALS： Tamoxifen was provided by Fudan Forward, China. Rabbit anti-mouse NGF was purchased from Santa Cruz Corporation, USA; rabbit anti-protein gene product 9.5 （PGP9.5） and rabbit anti-substance P （SP） were purchased from Chemicon, USA. METHODS： A total of 40 newborn ICR mice were randomly assigned to adenomyosis model and control groups, with 20 animals in each group. Mice in the adenomyosis model group were orally administrated 2.7 μmol/kg tamoxifen on days 2-5 after birth, while the controls were not treated. MAIN OUTCOME MEASURES： Both uteri from all mice were harvested at days 135-145 after birth Expressions of polyclonal PGP9.5 and SP were immunohistochemically detected to demonstrate pan- and sensory nerve fibers. Microvessel density was quantified in the endometrium and myometrium using immunochemical staining for polyclonal rabbit anti-CD31, which stained vessels. Gene expression for NGF, high-affinity tyrosine kinase receptor （trkA）, p75 neuretrophin receptor （p75NTR）, bradykinin receptor-1 （BKR-1）, and 2 （BKR-2）, as well as substance P receptor （neurokininl receptor, NK1-R）, were detected by reverse transcription-polymerase chain reaction. NGF-13 protein expression was detected by Western blot analysis. RESULTS： More nerve fibers were stained with PGP9.5 in the endometrium and myometrium, and with SP in the endometrium, in adenomyosis mice compared with controls （P 〈 0.0

关键词： adenomyosis innervation nerve growth factor inflammation vascularization

High-level representation sketch for video event retrieval

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Science China(Information Sciences) 2016年第7期59卷 158-172页

作者： Yu zhang xiaowu CHEN Liang LIN Changqun xia Dongqing zou State Key Laboratory of Virtual Reality Technology and Systems School of Compute Science and EngineeringBeihang University School of Advanced Computing Sun Yat-Sen University

Representing video events is an essential step for a wide range of visual applications. In this paper,we propose the event sketch, a high-level event representation, to depict the dynamic properties of video events composed of actions of semantic objects. We show that this representation can facilitate a novel sketch based video retrieval(SBVR) system, which has not been considered before to the best of our knowledge. In this system, users are allowed to draw the evolutions(e.g. spatiotemporal layouts and behaviors of semantic objects)on a board, and retrieve the events whose semantic objects have the similar evolutions from a database. To do this, event sketches are constructed on both the user queries and database videos, and compared under a novel graph-matching scheme based on data-driven Monta Carlo Markov chain(DDMCMC). To test our approach, we collect a novel dataset of goal events in real soccer videos, which consists actions of multiple players and shows large variability in the evolution process of the events. Experiments on this dataset and the publicly available dataset CAVIAR demonstrated the effectiveness of the proposed approach.

关键词： video retrieval event representation event sketch drawing board distance function relevance feedback DDMCMC

Single channel speech enhancement via time-frequency dictionary learning

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Chinese Journal of Acoustics 2013年第1期32卷 90-102页

作者： HUANG Jianjun zhang xiongwei zhang Yafei zou xia Institute of Command Automation PLA Univ.of Sci.&Tech

A time-frequency dictionary learning approach is proposed to enhance speech con- taminated by additive nonstationary noise. In this framework, a time-frequency dictionary which is learned from noise data is incorporated into the convolutive nonnegative matrix fac- torization framework. The update rules for the time-varying gains and speech dictionary are derived by precomputing the noise dictionary. The magnitude spectra of speech are estimated using convolution operation between the learned speech dictionary and the time-varying gains. Finally, noise is removed via binary time-frequency masking. The experimental results indi- cate that the proposed scheme gives better enhancement results in terms of quality measures of speech. Moreover, the proposed algorithm outperforms the multiband spectra subtraction and the non-negative sparse coding based noise reduction algorithm in nonstationary noise conditions.

关键词： time work In STFT Single channel speech enhancement via time-frequency dictionary learning

Image Analysis for In-situ Detection of Agglomeration for Needle-like Crystals 36

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Image Analysis for In-situ Detection of Agglomeration for Ne...

Batch Scheduling with Deteriorating Jobs to Minimize the Total Completion Time

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作者： Kang zou Tao Liu Yan Huo Fangkun zhang xiongwei Ni Institute of Advanced Control Technology Dalian University of Technology School of Engineering and Physical Science Heriot-Watt University

ISBN: (纸本)9781538629185

A synthetic image analysis method is proposed for in-situ detection of particle agglomeration for monitoring crystallization processes,based on using a non-invasive imaging *** proposed method consists of image pre-processing,feature analysis,shape identification,and ***,in-situ captured images are pre-processed to eliminate the influence from uneven illumination background and particle ***,based on choosing the fundamental image features of needle-like crystals,a texture computation algorithm is established with a gray level co-occurrence matrix（GLCM） defined for different particle ***,a shape identification algorithm is given to distinguish the primary particles from overlapped particles in a captured ***,a re-segmentation algorithm is constructed to separate individual crystals from the overlapped crystals,by using a geometric approach and the chord-to-point distance accumulation（CPDA） technique,and then pseudo agglomerates are recognized from the overlapped crystals based on the texture *** results on the cooling crystallization of β form L-glutamic acid well demonstrate the effectiveness of the proposed image analysis method.

关键词： image analysis agglomeration texture feature re-segmentation

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Journal of the Operations Research Society of China 2013年第3期1卷 377-383页

作者： Cuixia Miao Yunjie xia Yuzhong zhang Juan zou School of Mathematical Sciences Qufu Normal UniversityQufuShandong273165P.R.China School of Physics and Engineering Qufu Normal UniversityQufuShandong273165P.R.China School of Office Qufu Normal UniversityQufuShandong273165P.R.China School of Management Sciences Qufu Normal UniversityRizhaoShandong276826P.R.China

We consider bounded parallel-batch scheduling with proportional-linear deteriorating jobs and the objective to minimize the total completion *** give some properties of optimal schedules for the problem and present for it a dynamic programming algorithm running in O(b^(2)m^(2)2^(m))time,where b is the size of a batch and m is the number of distinct deterioration rates.

关键词： Batch scheduling Deteriorating jobs Dynamic programming algorithm

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线谱对参数预测多级矢量量化联合优化算法

数据采集与处理 2008年第2期23卷 186-190页

作者：邹霞张雄伟解放军理工大学通信工程学院南京210007

提出了一种线谱对参数预测多级矢量量化联合优化算法。该算法对预测系数和多级矢量量化采用渐进闭环设计,通过迭代实现预测系数和多级矢量量化设计的联合优化。在多级矢量量化设计过程中,采用迭代优化实现多级码本的联合优化。采用语音... 详细信息

提出了一种线谱对参数预测多级矢量量化联合优化算法。该算法对预测系数和多级矢量量化采用渐进闭环设计,通过迭代实现预测系数和多级矢量量化设计的联合优化。在多级矢量量化设计过程中,采用迭代优化实现多级码本的联合优化。采用语音线谱对参数对量化算法进行测试。测试结果表明,与传统算法相比,该量化算法可以减小线谱对参数量化失真,提高编码语音质量。

关键词：语音编码预测矢量量化多级矢量量化线谱对