检索结果-内蒙古大学图书馆

International Workshop on Acoustic signal Enhancement (IWAENC)

作者： Christin Baasch Vasudev Kandade Rajan Mohamed Krini Gerhard Schmidt Digital Signal Processing and System Theory Kiel University Germany Paragon AG Delbrueck Germany

In this paper a simple yet robust noise power spectral density estimation algorithm is presented. The motivation for the algorithm developed here is the harsh noise environment present in automobiles along with the need to keep the complexity low for real-time implementations. The scheme is based on a multiplicative estimator in which multiple increment and decrement time-constants are utilized. The time-constants are chosen based on noise-only and speech-like situations. Further, by observing the long-term “trend” of the noisy input spectrum, suitable time-constants are chosen which reduces the tracking delay significantly. The trend factor is measured taking into account the dynamics of speech. Evaluation of the proposed algorithm and comparisons with state of the art systems will be performed in the context of varying automobile noises.

关键词： Speech Noise measurement Market research Estimation Smoothing methods signal to noise ratio

来源：评论

学校读者我要写书评

暂无评论

Individual-gating-by-sorting in MHT

Individual-gating-by-sorting in MHT

引用

International Conference on Information Fusion

作者： Viet Due Nguyen Tim Claussen Digital Signal Processing and System Theory Christian-Albrechts-Universität zu Kiel Kiel Germany

An efficient individual gating method is described and tested. Compared to other approaches it does not solely calculate distances between the predicted and the actual measurement but checks for overlapping frames centered around them. In contrast to covariance ellipses, these frames are created only by using the main diagonal entries of covariance matrices. The overlap-check is done by sorting algorithms and binary search. Only measurements which pass the overlap-check are further processed by ellipsoid gating. In doing so, not only the computation time itself but also the complexity can be reduced compared to classical ellipsoid or rectangular gating. This Individual-Gating-by-Sorting is integrated into a Multi-Hypothesis tracker and applied to a multistatic sonar dataset. Results show outstanding performances. The gain compared to classical ellipsoid gating in terms of computation even further increases as the amount of data increases.

关键词： Logic gates Ellipsoids Position measurement Complexity theory Covariance matrices Target tracking Technological innovation

来源：评论

学校读者我要写书评

暂无评论

A Minimum variance beamformer for spatially distributed microphones using a soft reference selection

A Minimum variance beamformer for spatially distributed micr...

引用

Hands-Free Speech Communication and Microphone Arrays, HSCMA

作者： Sebastian Stenzel Jürgen Freudenberger Gerhard Schmidt HTWG Konstanz Institute for System Dynamics Germany Christian-Albrechts-University Kiel Digital Signal Processing and System Theory Germany

The signal quality at different microphone locations varies for distributed microphone arrays. Such microphone constellations require a suitable beamformer design that considers these differences in the input signal conditions. In this paper a frequency domain minimum variance (MV) beamforming approach is presented that uses a soft reference selection. The filter coefficients of this MV beamformer only depend on the spatial correlation properties of the input signals. The proposed beamformer is able to partially equalize the acoustic system, i.e. the magnitude of the overall transfer function is the envelope of all acoustic transfer functions.

关键词： Microphones Speech Transfer functions Acoustics signal to noise ratio Correlation

来源：评论

学校读者我要写书评

暂无评论

Effects of ON and OFF subthalamic nucleus deep brain stimulation on cortical activation during finger movements tasks: a simultaneous fNIRS and EEG study

引用

Brain Stimulation 2015年第2期8卷 393-393页

作者： M. Muthalib A.E. Taser J. Raethjen S. Perrey G. Schmidt G. Deuschl M. Muthuraman Movement To Health (M2H) Laboratory EuroMov Montpellier-1 University France Department of Neurology Christian-Albrechts University Kiel Germany Digital Signal Processing and System Theory Technical Faculty Kiel Germany

来源：评论

学校读者我要写书评

暂无评论

Multi-modal causality analysis of eyes-open and eyes-closed data from simultaneously recorded EEG and MEG

Multi-modal causality analysis of eyes-open and eyes-closed ...

引用

Annual International Conference of the IEEE Engineering in Medicine and Biology Society

作者： Abdul Rauf Anwar Kidist Gebremariam Mideska Helge Hellriegel Nienke Hoogenboom Holger Krause Alfons Schnitzler Gunther Deuschl Jan Raethjen Ulrich Heute Muthuraman Muthuraman Faculty of Electrical Engineering Digital Signal Processing and System Theory University of Kiel Department of Neurology Universitatsklinikum Schleswig-Holstein Department of Neurology Heinrich-Heine University

ISBN: (纸本)9781424479276

Owing to the recent advances in multi-modal data analysis, the aim of the present study was to analyze the functional network of the brain which remained the same during the eyes-open (EO) and eyes-closed (EC) resting task. The simultaneously recorded electroencephalogram (EEG) and magnetoencephalogram (MEG) were used for this study, recorded from five distinct cortical regions of the brain. We focused on the 'alpha' functional network, corresponding to the individual peak frequency in the alpha band. The total data set of 120 seconds was divided into three segments of 18 seconds each, taken from start, middle, and end of the recording. This segmentation allowed us to analyze the evolution of the underlying functional network. The method of time-resolved partial directed coherence (tPDC) was used to assess the causality. This method allowed us to focus on the individual peak frequency in the 'alpha' band (7-13 Hz). Because of the significantly higher power in the recorded EEG in comparison to MEG, at the individual peak frequency of the alpha band, results rely only on EEG. The MEG was used only for comparison. Our results show that different regions of the brain start to 'disconnect' from one another over the course of time. The driving signals, along with the feedback signals between different cortical regions start to recede over time. This shows that, with the course of rest, brain regions reduce communication with each another.

关键词： Electroencephalography Brain models Mathematical model Time-frequency analysis Time series analysis Bidirectional control

来源：评论

学校读者我要写书评

暂无评论

V5. Dynamic imaging of coherent sources in continues spikes and waves during slow sleep.

引用

Clinical Neurophysiology 2015年第8期126卷 e66-e66页

作者： Natia Japaridze Muthuraman Muthuraman Dierk Carina Anwar Abdul Rauf Deuschl Günther Stephani Urlich Siniatchkin Michael Department of Neuropediatrics Christian-Albrechts-University Kiel Germany Department of Neurology Christian-Albrechts-University Kiel Germany Digital Signal Processing and System Theory CAU Kiel Germany Northern German Epilepsy Centre for Children & Adolescents Schwentinental/OT Raisdorf Germany

The network of sources involved in the frequency oscillations of continuous spikes and waves during slow wave sleep and their causal architecture is still lacking in the current literature. In a couple of studies the network and causal connectivity was studied using fMRI by concentrating the analysis on the spikes and not on the background oscillations. In a number of studies the connectivity and the network of sources were studied during normal subjects sleep using fMRI. However, the earlier estimations do not directly relate to the background oscillations present during the interictal epileptiform patterns during sleep. In contrast the dynamic source coherence method is a tool to study the causality on the cortical and sub-cortical source level. In this study we measured the functional and directed connectivity with renormalized partial directed coherence during continuous spikes and waves during slow wave sleep EEG recordings from 12 patients. The network of sources involved was premotor cortex, posterior cingulate cortex, dorsolateral prefrontal cortex, middle temporal gyrus, medial thalamus and cerebellum. The cerebellum, thalamus and the posterior cingulate cortex showed significant bi-directional causality whereas all the other the sources showed uni-directional causality. Our results suggest that the mean source coherence could be an early biomarker for onset and severity of the disease. In addition we show the source network and the directed connectivity of the background frequency oscillations for continuous spikes and waves during slow wave sleep. Natia Japaridze and Muthuraman Muthuraman contributed equally to this paper.

关键词： CSWS DICS RDPC EEG

来源：评论

学校读者我要写书评

暂无评论

signal processing for microphone arrays on seat belts

Signal processing for microphone arrays on seat belts

引用

6th Biennial Workshop on digital signal processing for In-Vehicle systems and Safety 2013, DSP 2013

作者： Rajan, Vasudev Kandade Rohde, Sebastian Schmidt, Gerhard Withopf, Jochen Digital Signal Processing and System Theory Kiel University Germany

Microphones placed on the seat belts of an automobile (in the following shortly called beltmics) are an interesting alternative compared to other sensor positions. Because of the small distance to the talker's mouth, usually a good signal quality (e.g. measured in terms of high signal-tonoise ratio) can be achieved. However, the signals may also be disturbed because beltmics can easily be touched by, e.g., clothes and they might be in the air stream of automotive ventilation systems. In addition, applying array processing techniques is difficult because the geometry is flexible and may change over time. This paper presents signal enhancement algorithms designed for beltmics including echo cancellation, estimation of instationary noise, and microphone combining techniques. Results based on a real-time implementation are shown.

关键词： Beamforming

来源：评论

学校读者我要写书评

暂无评论

Coherent source and connectivity analysis on simultaneously measured EEG and MEG data during isometric contraction

Coherent source and connectivity analysis on simultaneously ...

引用

Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC)

作者： M. Muthuraman H. Hellriegel N. Hoogenboom A. R. Anwar K. G. Mideksa H. Krause A. Schnitzler J. Raethjen G. Deuschl Department of Neurology Christian Albrecht's university Kiel Germany Department of Neurology Heinrich-Heine University Dusseldorf Germany Institute for Digital Signal Processing and System Theory Faculty of Engineering Christian Albrecht's university Kiel 24143 Germany

The most well-known non-invasive electric and magnetic field measurement modalities are the electroencephalography (EEG) and magnetoencephalography (MEG). The first aim of the study was to implement the recently developed realistic head model which uses an integrative approach for both the modalities. The second aim of this study was to find the network of coherent sources and the modes of interactions within this network during isometric contraction (ISC) at (15-30 Hz) in healthy subjects. The third aim was to test the effective connectivity revealed by both the modalities analyzing them separately and combined. The Welch periodogram method was used to estimate the coherence spectrum between the EEG and the electromyography (EMG) signals followed by the realistic head modelling and source analysis method dynamic imaging of coherent sources (DICS) to find the network of coherent sources at the individual peak frequency within the beta band in healthy subjects. The last step was to identify the effective connectivity between the identified sources using the renormalized partial directed coherence method. The cortical and sub-cortical network comprised of the primary sensory motor cortex (PSMC), secondary motor area (SMA), and the cerebellum (C). The cortical and sub-cortical network responsible for the isometric contraction was similar in both the modalities when analysing them separately and combined. The SNR was not significantly different between the two modalities separately and combined. However, the coherence values were significantly higher in the combined modality in comparison to each of the modality separately. The effective connectivity analysis revealed plausible additional connections in the combined modality analysis.

关键词： Electroencephalography Coherence Brain modeling Electromyography Electrodes Head Magnetic heads

来源：评论

学校读者我要写书评

暂无评论

Reducing computational complexity of gating procedures using sorting algorithms

Reducing computational complexity of gating procedures using...

引用

16th International Conference of Information Fusion, FUSION 2013

作者： Nguyen, Viet Duc Claussen, Tim Digital Signal Processing and System Theory Christian-Albrechts-Universität zu Kiel Germany

ISBN: (纸本)9786058631113

Gating is an important part in many data association algorithms, specifically tracking algorithms. Its purpose is the preselection of suitable measurements or observations respectively in order to avoid unlikely measurement-to-track associations. As such, it can be essential for a low computational load. A very common gating method is individual ellipsoidal gating incorporating the Mahalanobis distance. On the one hand it is a reliable gating method used in many different tracking techniques, e.g., the global nearest neighbor method or the Multi-Hypothesis Tracking approach, but on the other hand it can be also very time consuming due to the inversions of covariance matrices related to all the measurement-to-track pairs. In this paper a Gating-by-Sorting approach is proposed to accelerate the gating procedure significantly. It uses sorting algorithms to carry out coarse gating followed by a second ellipsoidal gating step. The gating approach is incorporated into a multi-hypothesis tracker and applied to a real radar dataset. Results are obtained by measuring the computational load within tracking processes. They show that the proposed gating algorithm outperforms classical ellipsoidal gating by orders of magnitude. © 2013 ISIF ( Intl Society of Information Fusi.

关键词： Covariance matrix

来源：评论

学校读者我要写书评

暂无评论

Is Intelligibility Still the Main Problem? A Review of Perceptual Quality Dimensions of Synthetic Speech 8

Is Intelligibility Still the Main Problem? A Review of Perce...

引用

8th ISCA Tutorial and Research Workshop on Speech Synthesis, SSW 2013

作者： Hinterleitner, Florian Norrenbrock, Christoph R. Möller, Sebastian Quality and Usability Lab TU Berlin Germany Digital Signal Processing and System Theory CAU Kiel Germany

In this paper, we present a comparative overview of 9 studies on perceptual quality dimensions of synthetic speech. Different subjective assessment techniques have been used to evaluate the text-to-speech (TTS) stimuli in each of these tests: in a semantic differential, the test participants rate every stimulus on a given set of rating scales, while in a paired comparison test, the subjects rate the similarity of pairs of stimuli. Perceptual quality dimensions can be derived from the results of both test methods, either by performing a factor analysis or via multidimensional scaling. We show that even though the 9 tests differ in terms of used synthesizer types, stimulus duration, language, and quality assessment methods, the resulting perceptual quality dimensions can be linked to 5 universal quality dimensions of synthetic speech: (i) naturalness of voice, (ii) prosodic quality, (iii) fluency and intelligibility, (iv) disturbances, and (v) calmness. © SSW 2013. All rights reserved.

关键词： Quality control

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：