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239
Functional Phonology  Formalizing the interactions between articulatory and perceptual drives
, 1998
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Physical Modeling with the 2D Digital Waveguide Mesh
, 1993
"... An extremely efficient method for modeling wave propagation in a membrane is provided by the multidimensional extension of the digital waveguide. The 2D digital waveguide mesh is constructed out of bidirectional delay units and scattering junctions. We show that it coincides with the standard finit ..."
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Cited by 62 (7 self)
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An extremely efficient method for modeling wave propagation in a membrane is provided by the multidimensional extension of the digital waveguide. The 2D digital waveguide mesh is constructed out of bidirectional delay units and scattering junctions. We show that it coincides with the standard finite difference approximation scheme for the 2D wave equation, and we derive the dispersion error. Applications may be found in physical models of drums, soundboards, cymbals, gongs, smallbox reverberators, and other acoustic constructs where a onedimensional model is less desirable. 1 Background Theory There are many musical applications of the onedimensional digital waveguide ranging from the generation of wind and string instrument tones, to flanging effects [Van Duyne and Smith, 1992], to reverberation [Smith, 1987]. We review the theoretical derivation of onedimensional traveling waves as a basis for development of the twodimensional digital waveguide mesh. 1.1 The 1D Wave Equation...
Efficient Synthesis of Stringed Musical Instruments
, 1993
"... Techniques are described for reducing complexity in stringed instrument simulation for purposes of digital synthesis. These include commuting losses and dispersion to consolidate them into a single lter, replacing body resonators by lookup tables, simplied bowstring interaction, and singlelter ..."
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Cited by 56 (1 self)
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Techniques are described for reducing complexity in stringed instrument simulation for purposes of digital synthesis. These include commuting losses and dispersion to consolidate them into a single lter, replacing body resonators by lookup tables, simplied bowstring interaction, and singlelter, multiplyfree coupled strings implementation. Contents 1 Digital Waveguide Theory 2 2 The Terminated String 4 3 Simplied Body Filters 5 4 Simplied Bowed Strings 8 5 Coupled Strings 10 6 Summary 14 7 Appendix 14 1 Page 2 1 Digital Waveguide Theory This section summarizes the digital waveguide model for vibrating strings. Further details can be found in [Smith 1992]. Position y (t,x) 0 x . . . . . . 0 K String Tension e = Mass/Length Figure 1: The ideal vibrating string. The wave equation for the ideal (lossless, linear, exible) vibrating string, depicted in Fig. 1, is given by Ky 00 = y where K = string tension y = y(t; x) = linear mass density _ y...
Listen to your Data: ModelBased Sonification for Data Analysis
 189–194, Int. Inst. for Advanced Studies in System research and cybernetics
, 1999
"... Sonification is the use of nonspeech audio to convey information. We are developing tools for interactive data exploration, which make use of sonification for data presentation. In this paper, modelbased sonification is presented as a concept to design auditory displays. Two designs are described: ..."
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Cited by 42 (14 self)
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Sonification is the use of nonspeech audio to convey information. We are developing tools for interactive data exploration, which make use of sonification for data presentation. In this paper, modelbased sonification is presented as a concept to design auditory displays. Two designs are described: (1) particle trajectories in a "data potential" is a sonification model to reveal information about the clustering of vectorial data and (2) "datasonograms" is a sonification for data from a classification problem to reveal information about the mixing of distinct classes.
The Plenacoustic Function and its Sampling
 IEEE Transactions on Signal Processing
, 2006
"... Abstract—The spatialization of the sound field in a room is studied, in particular the evolution of room impulse responses as a function of their spatial positions. It was observed that the multidimensional spectrum of the solution of the wave equation has an almost bandlimited character. Therefore, ..."
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Cited by 37 (20 self)
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Abstract—The spatialization of the sound field in a room is studied, in particular the evolution of room impulse responses as a function of their spatial positions. It was observed that the multidimensional spectrum of the solution of the wave equation has an almost bandlimited character. Therefore, sampling and interpolation can easily be applied using signals on an array. The decay of the spectrum is studied on both temporal and spatial frequency axes. The influence of the decay on the performance of the interpolation is analyzed. Based on the support of the spectrum, the number and the spacing between the microphones is determined for the reconstruction of the sound pressure field up to a certain temporal frequency and with a certain reconstruction quality. The optimal sampling pattern for the microphone positions is given for the linear, planar and threedimensional case. Existing techniques usually make use of room models to recreate the sound field present at some point in the space. The presented technique simply starts from the measurements of the sound pressure field in a finite number of positions and with this information the sound pressure field can be recreated at any spatial position. Finally, simulations and experimental results are presented and compared with the theory. Index Terms—Interpolation, plenoptic function, room impulse response, sampling, sound pressure field sampling. I.
An Acoustic Analysis Of SingleReed Woodwind Instruments With An Emphasis On Design And Performance Issues And Digital Waveguide Modeling Techniques
, 1997
"... this paper, many of the saxophone mouthpiece facing designs prevalent in the 1920's were such that the reed frequency could not be raised much above the playing frequency of notes in the top of the second register. The notes written at about D6 could be achieved as reed regimes, but it was not ..."
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Cited by 28 (8 self)
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this paper, many of the saxophone mouthpiece facing designs prevalent in the 1920's were such that the reed frequency could not be raised much above the playing frequency of notes in the top of the second register. The notes written at about D6 could be achieved as reed regimes, but it was not possible to play many notes in the third register of the instrument. It was also not possible to play the second register without opening the register hole, because the reed frequency was too low to add energy to the oscillation at a higher component. More recent mouthpiece facing designs have allowed the reed frequency to be raised to a range analogous to that of the clarinet so that the third register is possible and the second register can be played without the register hole (Thompson, 1979). Given the fact that Adolphe Sax demonstrated a three octave range on the saxophone in the 1840's (Rascher, 1970), the validity of this example is unlikely. Further, this author has performed on saxophone mouthpieces (and instruments) from the 1920's and has never had difficulty achieving a range of at least three and a half octaves. Performers of reed woodwinds are typically affected by instrument response problems when they CHAPTER 2. ACOUSTICAL ASPECTS OF WOODWIND DESIGN & PERFORMANCE 87 travel to locations of significant elevation difference from their normal place of practice. By considering the reed's role as a pressuredependent air valve, it is reasonable to expect variations in reed response between different elevations. At high elevations, the ambient air pressure is lower. Thus, the pressure variations within the air column will oscillate about a lower ambient pressure value. Because the reed functions properly for a particular range of pressure differences across it and becaus...
Modeling of tension modulation nonlinearity in plucked strings
 DAFX7 Proc. of the 12th Int. Conference on Digital Audio Effects (DAFx09
, 2000
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The acoustics of fricative consonants
 unpublished PhD Dissertation, MIT
, 1985
"... The acoustic mechanism of fricative consonants was studied in the context of three domains: speech, mechanical models. and theoretical models. All fricative configurations have in common a small turbulenceproducing constriction within the vocal tract. Thus, preliminary experiments were conducted us ..."
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Cited by 19 (2 self)
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The acoustic mechanism of fricative consonants was studied in the context of three domains: speech, mechanical models. and theoretical models. All fricative configurations have in common a small turbulenceproducing constriction within the vocal tract. Thus, preliminary experiments were conducted using a mechanical model having this basic configuration of a constriction in a tube. Parameters such as constriction area. length. location, and degree of inlet tapering, and presence of an obstacle, were varied. It was found that acoustically the most significant parameters are the presence of an obstacle, the length of the front cavity, and the flowrate. Therefore, configurations in which only these parameters were varied, referred to as the obstacle and noobstacle cases, were examined more thoroughly and modeled theoretically. A source function for the obstacle case was derived from the farfield sound pressure measured when the obstacle was located in space, downstream of a constriction in a baffle. The directivity pattern produced by the obstacle in this position was similar to that of a dipole, as expected. A dipole source located inside a duct is equivalent to a pressure source in a transmnissionlille model, when only the longitudinal modes of a duct are considered. The filter
Discrete Frequency Warped Wavelets: Theory and Applications
 IEEE Trans. Signal Processing
, 1998
"... In this paper, we extend the definition of dyadic wavelets to include frequency warped wavelets. The new wavelets are generated and the transform computed in discretetime by alternating the Laguerre transform with perfect reconstruction filterbanks. This scheme provides the unique implementation of ..."
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Cited by 16 (8 self)
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In this paper, we extend the definition of dyadic wavelets to include frequency warped wavelets. The new wavelets are generated and the transform computed in discretetime by alternating the Laguerre transform with perfect reconstruction filterbanks. This scheme provides the unique implementation of orthogonal or biorthogonal warped wavelets by means of rational transfer functions. We show that the discretetime warped wavelets lead to welldefined continuoustime wavelet bases, satisfying a warped form of the twoscale equation. The shape of the wavelets is not invariant by translation. Rather, the "wavelet translates" are obtained from one another by allpass filtering. We show that the phase of the delay element is asymptotically a fractal. A feature of the warped wavelet transform is that the cutoff frequencies of the wavelets may be arbitrarily assigned while preserving a dyadic structure. The new transform provides an arbitrary tiling of the timefrequency plane, which can be designed by selecting as little as a single parameter. This feature is particularly desirable in cochlear and perceptual models of speech and music, where accurate bandwidth selection is an issue. As our examples show, by defining pitchsynchronous wavelets based on warped wavelets, the analysis of transients and denoising of inharmonic pseudoperiodic signals is greatly enhanced.
Mobile Robot Relocation from Echolocation Constraints
 IEEE Trans. Pattern Analysis and Machine Intelligence
, 2000
"... This paper presents a method for relocation of a mobile robot using sonar data. The process of determining the pose of a mobile robot with respect to a global reference frame in situations where no a priori estimate of the robot's location is available is cast as a problem of searching for corr ..."
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Cited by 12 (1 self)
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This paper presents a method for relocation of a mobile robot using sonar data. The process of determining the pose of a mobile robot with respect to a global reference frame in situations where no a priori estimate of the robot's location is available is cast as a problem of searching for correspondences between measurements and an a priori map of the environment. A physicallybased sonar sensor model is used to characterize the geometric constraints provided by echolocation measurements of different types of objects. Individual range returns are used as data features in a constraintbased search to determine the robot's position. A hypothesize and test technique is employed in which positions of the robot are calculated from all possible combinations of two range returns that satisfy the measurement model. The algorithm determines the positions which provide the best match between the range returns and the environment model. The performance of the approach is demonstrated using data from both a single scanning Polaroid sonar and from a ring of Polaroid sonar sensors.