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Ning Xiang - One of the best experts on this subject based on the ideXlab platform.

  • Diffusion equation modeling for Sound Energy flow analysis in multi domain structures
    Journal of the Acoustical Society of America, 2019
    Co-Authors: Erinç Odabaş, Ning Xiang, Mehmet Caliskan
    Abstract:

    This study investigates reliable models and methods to be applied in Sound field analysis of multi-domain structures. The case structures are two monuments, namely, Suleymaniye Mosque and Hagia Sophia in Istanbul. These are both multi-volume spaces with many smaller sub-volumes coupled to each other by coupling apertures in form of arches. A key concern of the study is to examine Energy flow decays and understand the mechanism of multi-slope Sound Energy decays. The methodology involves diffusion equation model (DEM) application in a finite-element scheme for Sound Energy flow analysis. Energy flow decays, Energy flow dips, and spatial flow vectors are examined for single versus multi-domain DEM solutions. It is concluded that specification of different domains with individual diffusion coefficients is a critical setting such that, if not assigned correctly, may mislead the results. The Energy flow vector analysis has enabled us to comprehend the architectural features in relation to such Energy flow decay dip occurrence. The computational efficiency of DEM is also discussed. The DEM application in this study has proved to be a powerful and practical method in room acoustics applications, specifically for multi-rate decay investigations.This study investigates reliable models and methods to be applied in Sound field analysis of multi-domain structures. The case structures are two monuments, namely, Suleymaniye Mosque and Hagia Sophia in Istanbul. These are both multi-volume spaces with many smaller sub-volumes coupled to each other by coupling apertures in form of arches. A key concern of the study is to examine Energy flow decays and understand the mechanism of multi-slope Sound Energy decays. The methodology involves diffusion equation model (DEM) application in a finite-element scheme for Sound Energy flow analysis. Energy flow decays, Energy flow dips, and spatial flow vectors are examined for single versus multi-domain DEM solutions. It is concluded that specification of different domains with individual diffusion coefficients is a critical setting such that, if not assigned correctly, may mislead the results. The Energy flow vector analysis has enabled us to comprehend the architectural features in relation to such Energy flow deca...

  • Assessment of Acoustical Indicators in Multi-domed Historic Structures by Non-exponential Energy Decay Analysis
    Acoustics Australia, 2018
    Co-Authors: Mehmet Caliskan, Ayşe Tavukçuoğlu, Ning Xiang
    Abstract:

    The key concern of this study is to discuss the reliable acoustical metrics for analyzing particular Sound fields within monumental multi-domed sacred spaces with an emphasis on multiple Sound Energy decay formation. The potential of such structures in featuring non-exponential Sound Energy decay characteristics necessitates new formulation of Sound decay indicators in understanding of their Sound fields. The early and late Energy decay components within non-exponential Sound Energy decays can have a unique contribution to the interior acoustic quality. These acoustical features can also provide the functional and spiritual acoustical needs of monumental sacred spaces. Süleymaniye Mosque and Hagia Sophia, two major monuments of Istanbul World Heritage Site, are examined in this regard. Field measurements are the main method of data collection. Over collected room impulse responses, relevant acoustical predictors including decay rates and decay times are computed by applying Bayesian decay parameter estimation. Analysis results disclose double or triple decay formations in both structures. Authors argue that, the detection of multiple Sound Energy decays in analyzed structures sets out a new vision for room acoustics studies of sacred spaces and for multi-domed monuments. Thus, implementation of new metrics, namely multiple slope decay parameters to replace classical room acoustics indicators, is recommended and discussed in light of the outcomes of this study.

  • Experimental investigations on Sound Energy propagation in acoustically coupled volumes using a high-spatial resolution scanning system
    Journal of the Acoustical Society of America, 2018
    Co-Authors: Ning Xiang, Aditya Alamuru, Ingo B. Witew, Michael Vorländer
    Abstract:

    The aim of this work is to study the Sound field distribution in an experimental scale-model of two coupled rooms. An automatic scanning mechanism moves a microphone in small grid steps to measure room impulse responses at each grid point. The measurements cover the entire two-dimensional area of the coupled rooms. Sound Energy distributions can be analyzed in the form of animated visual displays, revealing Sound propagation across the coupling aperture and inside each room. This paper describes the measurement results, and the analysis method, which offer deep insights into the temporal development of a Sound field in coupled spaces.The aim of this work is to study the Sound field distribution in an experimental scale-model of two coupled rooms. An automatic scanning mechanism moves a microphone in small grid steps to measure room impulse responses at each grid point. The measurements cover the entire two-dimensional area of the coupled rooms. Sound Energy distributions can be analyzed in the form of animated visual displays, revealing Sound propagation across the coupling aperture and inside each room. This paper describes the measurement results, and the analysis method, which offer deep insights into the temporal development of a Sound field in coupled spaces.

  • investigations on Sound Energy decays and flows in a monumental mosque
    Journal of the Acoustical Society of America, 2016
    Co-Authors: Ning Xiang, Mehmet Caliskan
    Abstract:

    This work investigates the Sound Energy decays and flows in the Suleymaniye Mosque in Istanbul. This is a single-space superstructure having multiple domes. The study searches for the non-exponential Sound Energy decay characteristics. The effect of different material surfaces and volumetric contributions are investigated using acoustic simulations and in situ acoustical measurements. Sound Energy decay rates are estimated by Bayesian decay analysis. The measured data reveal double- or triple-slope Energy decay profiles within the superstructure. To shed light on the mechanism of Energy exchanges resulting in multi-slope decay, spatial Sound Energy distributions and Energy flow vectors are studied by diffusion equation model (DEM) simulations. The resulting Sound Energy flow vector maps highlight the contribution of a Sound-reflective central dome contrasted with an absorptive carpeted floor in providing delayed Energy feedback. In contrast, no multi-slope Energy decay pattern is observed in DEM simulations with a bare marble floor, which generates a much more diffuse Sound field than in the real situation with a carpeted floor. The results demonstrate that Energy fragmentation, in support of the non-exponential Energy decay profile, is due to both the Sound absorption characteristics of materials and to their distributions, as well as to relations between the subvolumes of the mosque's interior.

  • Schroeder integration: Foundation for advanced Sound Energy decay analysis.
    Journal of the Acoustical Society of America, 2011
    Co-Authors: Ning Xiang
    Abstract:

    Schroeder’s backward integration method broke the new ground in classical architectural acoustics. Soon after publication of Schroeder’s backward integration method for obtaining Sound Energy decay functions from room‐impulse responses [Schroeder, J. Acoust. Soc. Am. 37, 409–412 (1965)], research activities in this field have been frequently reported in major journal publications. For reverberation time estimation based on a traditional straight‐line model, solutions to remedy problems related to the upper limit of backward integration and the background noise in experimentally measured Schroeder decay functions have emerged. Using a parametric model derived from the nature of Schroeder integration, this author proposed a nonlinear regression method [Xiang, J. Acoust. Soc. Am. 98, 2112–2121 (1995)]. The nonlinear regression method yields reverberation time estimates, insensitive to background noise, and the upper limit of integration. Recent interest in acoustically coupled‐volume systems has prompted new...

Svetha Venkatesh - One of the best experts on this subject based on the ideXlab platform.

  • ICME - Horror film genre typing and scene labeling via audio analysis
    2003 International Conference on Multimedia and Expo. ICME '03. Proceedings (Cat. No.03TH8698), 2003
    Co-Authors: Simon Moncrieff, Svetha Venkatesh, C. Dorai
    Abstract:

    We examine localised Sound Energy patterns, or events, that we associate with high level affect experienced with films. The study of Sound Energy events in conjunction with their intended affect enable the analysis of film at a higher conceptual level, such as genre. The various affect/emotional responses we investigate in this paper are brought about by well established patterns of Sound Energy dynamics employed in audio tracks of horror films. This allows the examination of the thematic content of the films in relation to horror elements. We analyse the frequency of Sound Energy and affect events at a film level as well as at a scene level, and propose measures indicative of the film genre and scene content. Using 4 horror, and 2 non-horror movies as experimental data we establish a correlation between the Sound Energy event types and horrific thematic content within film, thus enabling an automated mechanism for genre typing and scene content labeling in film.

  • Determining Affective Events Through Film Audio
    Media Computing, 2002
    Co-Authors: Simon Moncrieff, Chitra Dorai, Svetha Venkatesh
    Abstract:

    This chapter provides a brief introduction to the use of Sound in film as motivation for the examination of affective aspects of film audio. A method is presented to search the audio track of film for Sound Energy events that are hypothesized to be associated with an affect or a thematic event within the film. The Sound Energy events are characterized by specific patterns in the dynamics of the Sound Energy of the film audio. Four Sound Energy events are examined, each associated with a specific affect or symbolic meaning, that occur predominantly, although not solely, in films of the horror genre. The occurrences of the Sound Energy patterns of interest are investigated in six full length film audio tracks and experimental results are presented.

  • affect computing in film through Sound Energy dynamics
    ACM Multimedia, 2001
    Co-Authors: Simon Moncrieff, Chitra Dorai, Svetha Venkatesh
    Abstract:

    We develop an algorithm for the detection and classification of affective Sound events underscored by specific patterns of Sound Energy dynamics. We relate the portrayal of these events to proposed high level affect or emotional coloring of the events. In this paper, four possible characteristic Sound Energy events are identified that convey well established meanings through their dynamics to portray and deliver certain affect, sentiment related to the horror film genre. Our algorithm is developed with the ultimate aim of automatically structuring sections of films that contain distinct shades of emotion related to horror themes for nonlinear media access and navigation. An average of 82% of the Energy events, obtained from the analysis of the audio tracks of sections of four sample films corresponded correctly to the proposed affect. While the discrimination between certain Sound Energy event types was low, the algotithm correctly detected 71% of the occurrences of the Sound Energy events within audio tracks of the films analyzed, and thus forms a useful basis for determining affective scenes characteristic of horror in movies.

  • ACM Multimedia - Affect computing in film through Sound Energy dynamics
    Proceedings of the ninth ACM international conference on Multimedia - MULTIMEDIA '01, 2001
    Co-Authors: Simon Moncrieff, Chitra Dorai, Svetha Venkatesh
    Abstract:

    We develop an algorithm for the detection and classification of affective Sound events underscored by specific patterns of Sound Energy dynamics. We relate the portrayal of these events to proposed high level affect or emotional coloring of the events. In this paper, four possible characteristic Sound Energy events are identified that convey well established meanings through their dynamics to portray and deliver certain affect, sentiment related to the horror film genre. Our algorithm is developed with the ultimate aim of automatically structuring sections of films that contain distinct shades of emotion related to horror themes for nonlinear media access and navigation. An average of 82% of the Energy events, obtained from the analysis of the audio tracks of sections of four sample films corresponded correctly to the proposed affect. While the discrimination between certain Sound Energy event types was low, the algotithm correctly detected 71% of the occurrences of the Sound Energy events within audio tracks of the films analyzed, and thus forms a useful basis for determining affective scenes characteristic of horror in movies.

Simon Moncrieff - One of the best experts on this subject based on the ideXlab platform.

  • ICME - Horror film genre typing and scene labeling via audio analysis
    2003 International Conference on Multimedia and Expo. ICME '03. Proceedings (Cat. No.03TH8698), 2003
    Co-Authors: Simon Moncrieff, Svetha Venkatesh, C. Dorai
    Abstract:

    We examine localised Sound Energy patterns, or events, that we associate with high level affect experienced with films. The study of Sound Energy events in conjunction with their intended affect enable the analysis of film at a higher conceptual level, such as genre. The various affect/emotional responses we investigate in this paper are brought about by well established patterns of Sound Energy dynamics employed in audio tracks of horror films. This allows the examination of the thematic content of the films in relation to horror elements. We analyse the frequency of Sound Energy and affect events at a film level as well as at a scene level, and propose measures indicative of the film genre and scene content. Using 4 horror, and 2 non-horror movies as experimental data we establish a correlation between the Sound Energy event types and horrific thematic content within film, thus enabling an automated mechanism for genre typing and scene content labeling in film.

  • Determining Affective Events Through Film Audio
    Media Computing, 2002
    Co-Authors: Simon Moncrieff, Chitra Dorai, Svetha Venkatesh
    Abstract:

    This chapter provides a brief introduction to the use of Sound in film as motivation for the examination of affective aspects of film audio. A method is presented to search the audio track of film for Sound Energy events that are hypothesized to be associated with an affect or a thematic event within the film. The Sound Energy events are characterized by specific patterns in the dynamics of the Sound Energy of the film audio. Four Sound Energy events are examined, each associated with a specific affect or symbolic meaning, that occur predominantly, although not solely, in films of the horror genre. The occurrences of the Sound Energy patterns of interest are investigated in six full length film audio tracks and experimental results are presented.

  • affect computing in film through Sound Energy dynamics
    ACM Multimedia, 2001
    Co-Authors: Simon Moncrieff, Chitra Dorai, Svetha Venkatesh
    Abstract:

    We develop an algorithm for the detection and classification of affective Sound events underscored by specific patterns of Sound Energy dynamics. We relate the portrayal of these events to proposed high level affect or emotional coloring of the events. In this paper, four possible characteristic Sound Energy events are identified that convey well established meanings through their dynamics to portray and deliver certain affect, sentiment related to the horror film genre. Our algorithm is developed with the ultimate aim of automatically structuring sections of films that contain distinct shades of emotion related to horror themes for nonlinear media access and navigation. An average of 82% of the Energy events, obtained from the analysis of the audio tracks of sections of four sample films corresponded correctly to the proposed affect. While the discrimination between certain Sound Energy event types was low, the algotithm correctly detected 71% of the occurrences of the Sound Energy events within audio tracks of the films analyzed, and thus forms a useful basis for determining affective scenes characteristic of horror in movies.

  • ACM Multimedia - Affect computing in film through Sound Energy dynamics
    Proceedings of the ninth ACM international conference on Multimedia - MULTIMEDIA '01, 2001
    Co-Authors: Simon Moncrieff, Chitra Dorai, Svetha Venkatesh
    Abstract:

    We develop an algorithm for the detection and classification of affective Sound events underscored by specific patterns of Sound Energy dynamics. We relate the portrayal of these events to proposed high level affect or emotional coloring of the events. In this paper, four possible characteristic Sound Energy events are identified that convey well established meanings through their dynamics to portray and deliver certain affect, sentiment related to the horror film genre. Our algorithm is developed with the ultimate aim of automatically structuring sections of films that contain distinct shades of emotion related to horror themes for nonlinear media access and navigation. An average of 82% of the Energy events, obtained from the analysis of the audio tracks of sections of four sample films corresponded correctly to the proposed affect. While the discrimination between certain Sound Energy event types was low, the algotithm correctly detected 71% of the occurrences of the Sound Energy events within audio tracks of the films analyzed, and thus forms a useful basis for determining affective scenes characteristic of horror in movies.

Yun Jing - One of the best experts on this subject based on the ideXlab platform.

  • Sound Energy decay analysis in multiple coupled volume systems.
    Journal of the Acoustical Society of America, 2010
    Co-Authors: Ning Xiang, Philip W. Robinson, Yun Jing
    Abstract:

    There has been an increasing need in analyzing Sound Energy decays consisting of more than one decay slope, so‐called non‐single‐exponential decays. It has been considered very challenging to estimate parameters associated with double‐slope decay characteristics, even more challenging when the coupled‐volume systems contain more than two decay processes. To meet the need of characterizing Energy decays of multiple decay processes, this work reports investigations using both acoustical scale‐models and numerical models of three coupled volumes. Two levels of Bayesian inference: model selection and parameter estimation, have been applied to detection and characterization of Sound Energy decays. Experimental results measured in acoustical scale models and numerical results from diffusion‐equation‐based models are used to validate the Bayesian analysis methods. The analysis methods are then applied to geometric‐acoustics simulations of a conceptual concert hall. This work demonstrates that the analysis method...

  • Characterization of non-exponential Sound Energy decays in multiple coupled volumes
    2010
    Co-Authors: Ning Xiang, Philip W. Robinson, Yun Jing
    Abstract:

    Recent studies on acoustically coupled volumes, worship spaces, and in concert hall acoustics, have prompted an increasing interest in analyzing Sound Energy decays consisting of more than one decay slope, so-called nonexponential decays. It has been considered very challenging to estimate parameters associated with double-slope decay characteristics, even more challenging when the coupled-volume systems contain more than two decay processes. To meet the need of characterizing Energy decays of multiple decay processes, this paper reports investigations using both acoustical scale-models and numerical models of three coupled volumes. Characterization is based on Bayesian probabilistic inference. Acoustic scale models, and diffusion-equation based models are used to evaluate the estimation strategy, and to validate the results. The analysis method is then applied to geometric-acoustics models of concert halls with more complex geometries. The analysis method within Bayesian framework is capable of determining more than two decay slopes and estimating the corresponding decay parameters.

  • One-dimensional transport equation models for Sound Energy propagation in long spaces: Theory
    Journal of the Acoustical Society of America, 2009
    Co-Authors: Yun Jing, Edward W. Larsen, Ning Xiang
    Abstract:

    In this paper, a three-dimensional transport equation model is developed to describe the Sound Energy propagation in a long space. Then this model is reduced to a one-dimensional model by approximating the solution using the method of weighted residuals. The one-dimensional transport equation model directly describes the Sound Energy propagation in the “long” dimension and deals with the Sound Energy in the “short” dimensions by prescribed functions. Also, the one-dimensional model consists of a coupled set of N transport equations. Only N=1 and N=2 are discussed in this paper. For larger N, although the accuracy could be improved, the calculation time is expected to significantly increase, which diminishes the advantage of the model in terms of its computational efficiency.

  • visualizations of Sound Energy across coupled rooms using a diffusion equation model
    Journal of the Acoustical Society of America, 2008
    Co-Authors: Yun Jing, Ning Xiang
    Abstract:

    Visualizations, based on a diffusion equation model, are presented for both steady-state and transient Sound Energy. For steady-state Sound-pressure level distributions, animations created by scanning from the primary room to the secondary room reveal discontinuous transitions of Sound Energy caused by a location change from the wall area to the aperture area. Animations of time-dependent Energy flow directions visualize the Energy flows across coupled spaces. This study also reveals a “reversal” characteristic of Energy flow directions which seems to be dependent on the size and location of the aperture.

  • Predictions of Sound Energy flows in coupled spaces using a diffusion equation model.
    Journal of the Acoustical Society of America, 2008
    Co-Authors: Yun Jing, Ning Xiang
    Abstract:

    In this work, a diffusion equation model [J. Xiang, J. Acoust. Soc. Am., 123, 145–153 (2008)] is applied to two coupled spaces to study the time‐dependent Sound Energy flows through the coupling area (aperture). The Energy feedback is found when the primary room is less reverberant than the secondary room. The Bayesian framework is applied to quantify double‐slope characteristics of Sound‐Energy flow decays obtained from the diffusion equation numerical simulations. This work also reveals that the turning point on a double‐sloped Energy decay is highly correlated to the time instant when the Energy flow direction flips over.

L. Gerald Marshall - One of the best experts on this subject based on the ideXlab platform.