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Field-Data-Based Modeling of Medium-Frequency Induction Melting Furnaces for Power Quality Studies

IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS 2012年第4期48卷 1215-1224页

作者： Yilmaz, Ilker Salor, Ozgul Ermis, Muammer Cadirci, Isik Middle E Tech Univ Dept Elect & Elect Engn TR-06531 Ankara Turkey Sci & Technol Res Council Turkey TUBITAK Space Technol Res Inst UZAY Power Elect Grp TR-06531 Ankara Turkey

In this paper, the coreless medium-frequency induction melting furnace (IMF) system is represented by alternative field-data-based models, developed specifically for power quality studies. The IMF operation has been represented by a variable series RL circuit, to model the fundamental components of electrical quantities, and a shunt-connected current source, to model the generated harmonics and interharmonics over a typical melting cycle. Both the sinusoidal coding method applied to the major harmonics and interharmonics in the supply line currents obtained from field measurements and the raw data have been used in the developed models. It has been shown that the sinusoidal coding method can be used to satisfactorily represent the operation of the IMF system as seen from the supply terminals, with a minimum data storage requirement, and can be used to construct efficient IMF databases for power quality studies. The power quality problems of the IMF system, particularly the problematic time-varying interharmonic voltage distortion, and the interaction of those time-varying interharmonic currents with the passive shunt filter installations connected to the same bus have been investigated in detail, using the developed models.

关键词： Formant analysis induction melting furnace (IMF) modeling power quality sinusoidal coding

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Development of a 4 kbit/s hybrid sinusoidal/CELP speech coder

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SPEECH COMMUNICATION 2004年第3-4期42卷 353-371页

作者： Heikkinen, A Nokia Res Ctr Audio Visual Syst Lab FIN-33721 Tampere Finland

A comprehensive performance analysis of sinusoidal and code excited linear prediction (CELP) speech coding is given around 4 kbit/s, using both subjective and objective measurements. Based on the observations made, justification for the multi-modal hybrid coding approach employing both sinusoidal and CELP coding is given, and an implementation of such a coder is described. This 4 kbit/s sinusoidal/CELP speech coder utilizes four modes to classify the input speech segment: voiced, jittery-voiced, plosive and unvoiced. For voiced segments sinusoidal coding is used whereas different CELP versions are employed for the other modes. The quality of the implemented 4 kbit/s sinusoidal/ CELP speech coder in clean speech conditions is finally verified by a listening test. In the test, the 4 kbit/s coder performed almost as well as the high-quality references used, but it still needs improvements to be classified as a high-quality 4 kbit/s speech coder. (C) 2003 Elsevier B.V. All rights reserved.

关键词： speech coding hybrid coding sinusoidal coding CELP coding

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sinusoidal Sampling Enhanced Compressive Camera for High Speed Imaging

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IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE 2021年第4期43卷 1380-1393页

作者： Deng, Chao Zhang, Yuanlong Mao, Yifeng Fan, Jingtao Suo, Jinli Zhang, Zhili Dai, Qionghai Tsinghua Univ Beijing Key Lab Multidimens & Multiscale Computat Dept Automat Inst Brain & Cognit Sci Beijing 100084 Peoples R China High Tech Inst Xian Xian 710025 Peoples R China

Compressive sensing technique allows capturing fast phenomena at a much higher frame rate than the camera sensor, by recovering a frame sequence from their encoded combination. However, most conventional compressive video sensing methods limit the achieved frame rate improvement to tenfold and only support low resolution recovery. Making use of the camera's redundant spatial resolution for further frame rate improve, here we report a novel compressive video acquisition technique termed sinusoidal Sampling Enhanced Compressive Camera (S2EC2) to encode denser frames within a snapshot. Specifically, we decompose the dense frames into groups and apply combinational coding: random codes within each group for compressive acquisition;group specific sinusoidal codes to multiplex different groups onto the high resolution sensor. The sinusoidal codes designed for these groups would shift their frequency components by different offsets in the Fourier domain and staggered the dominant frequencies of the coded measurements of these groups. Correspondingly, the reconstruction successfully separate coded measurements of different groups and recovers frames within each group. Besides, we also solve the implementation problem of insufficient gray scale spatial light modulation speed, and build a prototype achieving 2000 fps reconstruction with a 15.6 fps camera (the actual compression ratio is 0.009). The extensive experiments validate the proposed approach.

关键词： Encoding Image reconstruction Cameras Image coding Frequency modulation Frequency-domain analysis Compressive sensing compressive video computational imaging image processing video processing sinusoidal coding high-speed video

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High-resolution spherical quantization of sinusoidal parameters

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IEEE TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING 2007年第3期15卷 966-981页

作者： Korten, Pirn Jensen, Jesper Heusdens, Richard Delft Univ Technol Dept Med NL-2628 CD Delft Netherlands

sinusoidal coding is an often employed technique in low bit-rate audio coding. Therefore, methods for efficient quantization of sinusoidal parameters are of great importance. In this paper, we use high-resolution assumptions to derive analytical expressions for the optimal entropy-constrained unrestricted spherical quantizers for the amplitude, phase, and frequency parameters of the sinusoidal model. This is done both for the case of a single sinusoid, and for the more practically relevant case of multiple sinusoids distributed across multiple segments. To account for psychoacoustical effects of the auditory system, a perceptual distortion measure is used. The optimal quantizers minimize a high-resolution approximation of the expected perceptual distortion, while the corresponding quantization indices satisfy an entropy constraint. The quantizers turn out to be flexible and of low complexity, in the sense that they can be determined easily for varying bit rate requirements, without any sort of retraining or iterative procedures. In an objective comparison it is shown that for the squared error distortion measure, the rate distortion performance of the proposed method is very close to that of the theoretically optimal entropy-constrained vector quantization. Furthermore, for the perceptual distortion measure, the proposed scheme is shown to objectively outperform an existing sinusoidal quantization scheme, where frequency quantization is done independently. Finally, a subjective listening test, in which the proposed scheme is compared to an existing state-of the-art sinusoidal quantization scheme with fixed quantizers for all input signals, indicates that the proposed scheme leads to an average bit rate reduction of 20%, at the same subjective quality level as the existing scheme.

关键词： high-resolution quantization point density functions sinusoidal coding unrestricted spherical quantization

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Multiple description trellis-coded quantization of sinusoidal parameters

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2008年第10期56卷 5287-5291页

作者： Larsen, Morten Holm Christensen, Mads Graesboll Jensen, Soren Holdt Aalborg Univ Dept Elect Syst Aalborg Denmark

A new scheme for sinusoidal audio coding named multiple description spherical trellis-coded quantization is proposed and analytic expressions for the point densities and expected distortion of the quantizers are derived based on a high-resolution assumption. The proposed quantizers are of variable dimensions meaning that any number of sinusoids can be quantized jointly for each audio segment whereby a lower distortion is achieved compared to previously published scalar spherical quantizers. The quantizers;are designed to minimize a perceptual distortion measure subject to an entropy constraint for a given packet-loss probability. In experiments, the performance of the quantizers is assessed and compared to the corresponding single description spherical quantizer and associated bounds under various conditions and is found to increase robustness towards packet-loss.

关键词： audio coding high-rate theory multiple description coding sinusoidal coding vector quantization

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Schemes for optimal frequency-differential encoding of sinusoidal model parameters

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SIGNAL PROCESSING 2003年第8期83卷 1721-1735页

作者： Jensen, J Heusdens, R Delft Univ Technol Dept Mediamat NL-2628 CD Delft Netherlands

sinusoidal coding plays an important role in low bit-rate audio coding. This paper considers frequency-differential encoding of the sinusoidal model parameters as an alternative to time-differential encoding. For a given signal frame, the parameters of each sinusoidal component may be encoded either differentially relative to other components in the same frame, or directly, i.e., without differential encoding. Using basic tools from graph theory, we derive several algorithms for finding bit-rate optimal combinations of direct and differential encoding of the sinusoidal parameters. In simulation experiments with audio signals, the algorithms showed bit-rate reductions of up to 28% relative to direct encoding. Furthermore, when compared to what can be considered a traditional FD encoding scheme (as used in MPEG-4 audio), the proposed algorithms achieve bit-rate reductions of up to 6%. (C) 2003 Elsevier Science B.V. All rights reserved.

关键词： sinusoidal coding frequency-differential encoding audio coding differential pulse code modulation (DPCM)

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Rate-distortion optimized quantization in multistage audio coding

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IEEE TRANSACTIONS ON AUDIO SPEECH AND LANGUAGE PROCESSING 2006年第1期14卷 311-320页

作者： Vafin, R Kleijn, WB Royal Inst Technol KTH Dept Signals Sensors & Syst Tallinn Estonia Royal Inst Technol Dept Signals Sensors & Syst S-10044 Stockholm Sweden

In this work, we develop a new method for quantization in multistage audio coding. Given a (perceptual) distortion measure and a bit-rate constraint, we analytically derive the optimal rate distribution between subcoders (stages) and the corresponding optimal quantizers using high-rate theory. The analytical solutions for optimal quantizers allow a coder to easily adapt to changes in bit-rate requirements. As an illustration of the new method, we consider quantization in a two-stage sinusoidal/wave form coder that is a widely used combination in audio coding. We show that at low total rates most of the rate should be assigned to the sinusoidal (model-based, subspace) subcoder, while at high total rates most of the rate should be assigned to the waveform (full-space) subcoder. We compare the new method to a reference quantization method that does not use rate-distortion optimization. A significantly higher performance of the new method is shown by means of a listening test.

关键词： audio coding high-rate theory modified discrete cosine transform (MDCT) multistage coding quantization rate-distortion optimization sinusoidal coding waveform coding

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A prototype system for object coding of musical audio

A prototype system for object coding of musical audio

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Workshop on Applications of Signal Processing to Audio and Acoustics

作者： Vincent, E Plumbley, MD Queen Mary Univ London Dept Elect Engn London E1 4NS England

ISBN: (纸本)0780391543

This article deals with low bitrate object coding of Musical audio, and more precisely with the extraction of pitched sound objects in polyphonic music. After a brief review of existing methods, we discuss the potential benefits of recasting this problem in a Bayesian framework. We define pitched objects by a set of probabilistic priors and derive efficient algorithms to infer active objects and their parameters. Preliminary experiments suggest that the proposed method results in it better sound quality than simple sinusoidal coding while achieving a lower bitrate.

关键词： Bayes methods audio coding music Bayesian framework musical audio object coding polyphonic music sinusoidal coding sound quality

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Modified Delta Encoding and Its Applications to Speech Signal

Modified Delta Encoding and Its Applications to Speech Signa...

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IEEE Region 10 Conference on TENCON 2010

作者： Ma, Yanna Noda, Hisayori Ito, Izumi Nishihara, Akinori Tokyo Inst Technol Tokyo 152 Japan

ISBN: (纸本)9781424468904

A modified delta encoding method a and its applications to speech signal are proposed. In this method, Hungarian algorithm is applied to find the minimum distance of arbitrary two frames in speech signal and minimum spanning tree is used to find an effective delta encoding path. In simulation, the method is applied to the compression of sinusoidal coding. The results show that the data size after compression is 6% smaller than a usual delta encoding whose path is not suitably permutated. In addition, the proposed method has the potential to apply on data security for practical use because the delta encoding path which can be used as the security key is unordered and long enough.

关键词： Delta Encoding Minimum Spanning Tree Hungarian Algorithm sinusoidal coding Data Security

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Optimal frequency-differential encoding of sinusoidal model parameters

Optimal frequency-differential encoding of sinusoidal model ...

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IEEE International Conference on Acoustics, Speech, and Signal Processing

作者： Jensen, J Heusdens, R Delft Univ Technol Dept Mediamat Delft Netherlands

ISBN: (纸本)0780374029

sinusoidal coding has proven to be efficient for low bit-rate audio coding. In this paper we consider schemes for frequency-differential (FD) encoding of the sinusoidal model parameters. For a given signal frame, the parameters of a sinusoidal component may be encoded either differentially relative to other components in the same frame, or directly, i.e., without differential encoding. Using basic tools from graph theory, two algorithms are derived for finding bit rate optimal combinations of direct and differential encoding of the sinusoidal parameters. In simulation experiments with audio signals, the algorithms showed bit-rate reductions of up to 27% relative to direct encoding. Furthermore, when compared to a commonly used FD encoding scheme, the proposed algorithms achieved bit rate reductions of up to 7%.

关键词： optimisation audio coding data compression graph theory optimal frequency-differential encoding sinusoidal model parameters sinusoidal coding graph theory bit rate optimal encoding simulation experiments audio signals bit-rate reduction low bit-rate audio compression low bit-rate audio coding

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