The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform

Mohamed Ichchou - One of the best experts on this subject based on the ideXlab platform.

  • Identification of acoustic sources through an inverse Energy Method
    Inverse Problems in Science and Engineering, 2011
    Co-Authors: Mohamed Chabchoub, Sébastien Besset, Mohamed Ichchou
    Abstract:

    International audienceThis article deals with the behaviour of acoustic cavities in the mid-high-frequency range. An Energy Method called simplified Energy Method (MES) has already been proposed to predict Energy levels in acoustic cavities. The direct MES provides Energy density repartitions from the knowledge of input power and power dissipated at the boundaries. In this article we propose that the MES can be used to solve inverse problems. More precisely, the dissipated Energy at the acoustic domain boundaries are retrieved from the knowledge of Energy densities. The inverse MES formulation is first defined and a simple acoustic cavity test case is analysed, displaying the efficiency of the proposed Method. The nature and the quality of input data as well as other parameters will be considered

  • Identification of acoustic sources through an inverse Energy Method
    Inverse Problems in Science and Engineering, 2011
    Co-Authors: Mohamed Chabchoub, Sébastien Besset, Mohamed Ichchou
    Abstract:

    This article deals with the behaviour of acoustic cavities in the mid-high-frequency range. An Energy Method called simplified Energy Method (MES) has already been proposed to predict Energy levels in acoustic cavities. The direct MES provides Energy density repartitions from the knowledge of input power and power dissipated at the boundaries. In this article we propose that the MES can be used to solve inverse problems. More precisely, the dissipated Energy at the acoustic domain boundaries are retrieved from the knowledge of Energy densities. The inverse MES formulation is first defined and a simple acoustic cavity test case is analysed, displaying the efficiency of the proposed Method. The nature and the quality of input data as well as other parameters will be considered.

  • Structural sources identification through an inverse mid-high frequency Energy Method
    Mechanical Systems and Signal Processing, 2011
    Co-Authors: Mohamed Chabchoub, Sébastien Besset, Mohamed Ichchou
    Abstract:

    This paper is primarily focused on the identification of structural forces, with the objective of localizing forces injected into structures in the mid-high frequency range. An Energy Method, called the simplified Energy Method (MES), has already been introduced for the purpose of predicting an Energy density distribution for structural acoustic problems in the mid-high frequency range. The present paper proposes using this same Energy Method to solve inverse structural problems. More specifically, the injected forces are to be estimated and localized through knowledge of a set of Energy densities within the structure. The 2D formulation of this inverse approach, known as inverse MES (or IMES), is first expressed. Both the boundary and internal sources can then be detected by applying the proposed formulation. Numerical test results are processed using a 2D Kirchhoff plate, and a number of conclusions are also drawn regarding IMES capabilities. Moreover, this paper offers a numerical comparison with another Energy-based Method.

  • An inverse mid-high frequency Energy Method: Formulation and applications
    2010
    Co-Authors: Olivier Bareille, Mohamed Chabchoub, Sébastien Besset, Mohamed Ichchou
    Abstract:

    An Energy Method called Simplified Energy Method (MES) has already been proposed to predict Energy densities repartition for structural-acoustic problems in the mid-high frequency range. In order to illustrate but also to present one of the applications of this Method, this latter is used here to solve inverse structural problems. The main application, in this paper, is the structural forces identification thanks to Energy densities calculation and analysis. The injected forces estimation and localization are hence obtained in the mid-high frequency range. Internal as well as boundary sources are here detected through 2D Kirchhoff-plate numerical tests.

Matthew Daum - One of the best experts on this subject based on the ideXlab platform.

  • Application of the Stress-Energy Method for Generating Corrugated Board Cushion Curves
    Journal of Testing and Evaluation, 2013
    Co-Authors: Matthew Daum, Duncan Darby, Gregory S. Batt, Lisi Campbell
    Abstract:

    Cushion curves are an important tool used for designing foam cushions, but no commercially available curves exist for corrugated board, despite its growing popularity as a cushioning material. This paper summarizes the theory and recent work applying the stress-Energy Method and different curve fit models to corrugated board for generating cushion curves. This paper also compares stress-Energy predicted deceleration values to actual ASTM D1596 deceleration values as a Method of determining whether the stress-Energy Method is a viable alternative for generating cushion curves for corrugated board. The results of this study suggest that the stress-Energy Method should not yet be recommended for generating cushion curves for corrugated board.

  • Evaluation of Predicted Deceleration Values From the Stress-Energy Method Compared to Actual Deceleration Values From the ASTM D1596 Test Method
    Journal of Testing and Evaluation, 2011
    Co-Authors: Matthew Daum
    Abstract:

    In recent years a simplified Method for generating cushion curves, called stress-Energy, has been presented as an alternative to ASTM D1596. A frequent question regarding the stress-Energy Method is the accuracy of the predicted deceleration compared to actual deceleration. This study compares the predicted deceleration values from the stress-Energy Method to the actual deceleration values collected from the ASTM D1596 test Method for several data sets of EPS and EPE molded foam. Results show the average difference between the stress-Energy predicted deceleration and the actual ASTM D1596 deceleration values to be 10 % or less for 144.2 kg/m3 EPE. Evaluating 20.0 kg/m3 EPS, the average difference between predicted and actual deceleration values is about 12 % or less. The study also found drop to drop deceleration to vary widely, so average actual deceleration was also evaluated compared to the predicted stress-Energy deceleration. As a result, both the EPE and EPS predicted deceleration can be shown to be within ±10% of the actual averaged deceleration, an accuracy useful for practical application.

Omer Deperlioglu - One of the best experts on this subject based on the ideXlab platform.

  • Segmentation of Heart Sounds by Re-Sampled Signal Energy Method
    2018
    Co-Authors: Omer Deperlioglu
    Abstract:

    Auscultation, which means listening to heart sounds, is one of the most basic medical Methods used by physicians to diagnose heart diseases. These voices provide considerable information about the pathological cardiac condition of arrhythmia, valve disorders, heart failure and other heart conditions. This is why cardiac sounds have a great prominence in the early diagnosis of cardiovascular disease. Heart sounds mainly have two main components, S1 and S2. These components need to be well identified to diagnose heart conditions easily and accurately. In this case, the segmentation of heart sounds comes into play and naturally a lot of work has been done in this regard. The first step in the automatic analysis of heart sounds is the segmentation of heart sound signals. Correct detection of heart sounds components is crucial for correct identification of systolic or diastolic regions. Thus, the pathological conditions in these regions can be clearly demonstrated. In previous studies, frequency domain studies such as Shannon Energy and Hilbert transformation Method were generally performed for segmentation of heart sounds. These Methods involve quite long and exhausting stages. For this reason, in this study, a re-sampled Energy Method which can easily segment heart sounds in the time domain has been developed. The results obtained from the experiments show that the proposed Method segments S1 and S2 sounds very efficiently.

  • SIU - Classification of heart sounds with re-sampled Energy Method
    2018 26th Signal Processing and Communications Applications Conference (SIU), 2018
    Co-Authors: Omer Deperlioglu
    Abstract:

    Due to the high number of heart diseases in the world and the increasing number of deaths resulting from them, the studies about early diagnosis of heart diseases has also increased. Studies on cardiac signals focus especially on the classification of heart sounds. Naturally, researches are generally concerned with increasing classification success. For this purpose, many studies use the separation of heart sounds into S1 and S2 segments by Methods such as shannon Energy, discreat wavelet transform and Hilbert transform. In this study, the use of signal Energy, which is used as a sub-Method of segmentation, has been explored for directly classification. For this purpose, the Energy of the heart sounds was calculated by the re-sampled Energy Method and the obtained data were classified by artificial neural networks. Especially in these studies, the effect of sampling time on classification success was investigated. The obtained results were compared within themselves and with classification by dataset of S1-S2 sounds segmented. It is show that if the sampling rate is reduced in the direct classification by the re-sampled Energy Method, the accuracy of the classification is seen to increase. In addition, accuracy of classification is higher than the classification made by the segmented data set. Here I have reached the conclusion that the Energy of heart sounds used to segment heart sounds can be used directly in classification studies and a more efficient classification performance can be achieved.

Mohamed Chabchoub - One of the best experts on this subject based on the ideXlab platform.

  • Identification of acoustic sources through an inverse Energy Method
    Inverse Problems in Science and Engineering, 2011
    Co-Authors: Mohamed Chabchoub, Sébastien Besset, Mohamed Ichchou
    Abstract:

    International audienceThis article deals with the behaviour of acoustic cavities in the mid-high-frequency range. An Energy Method called simplified Energy Method (MES) has already been proposed to predict Energy levels in acoustic cavities. The direct MES provides Energy density repartitions from the knowledge of input power and power dissipated at the boundaries. In this article we propose that the MES can be used to solve inverse problems. More precisely, the dissipated Energy at the acoustic domain boundaries are retrieved from the knowledge of Energy densities. The inverse MES formulation is first defined and a simple acoustic cavity test case is analysed, displaying the efficiency of the proposed Method. The nature and the quality of input data as well as other parameters will be considered

  • Identification of acoustic sources through an inverse Energy Method
    Inverse Problems in Science and Engineering, 2011
    Co-Authors: Mohamed Chabchoub, Sébastien Besset, Mohamed Ichchou
    Abstract:

    This article deals with the behaviour of acoustic cavities in the mid-high-frequency range. An Energy Method called simplified Energy Method (MES) has already been proposed to predict Energy levels in acoustic cavities. The direct MES provides Energy density repartitions from the knowledge of input power and power dissipated at the boundaries. In this article we propose that the MES can be used to solve inverse problems. More precisely, the dissipated Energy at the acoustic domain boundaries are retrieved from the knowledge of Energy densities. The inverse MES formulation is first defined and a simple acoustic cavity test case is analysed, displaying the efficiency of the proposed Method. The nature and the quality of input data as well as other parameters will be considered.

  • Structural sources identification through an inverse mid-high frequency Energy Method
    Mechanical Systems and Signal Processing, 2011
    Co-Authors: Mohamed Chabchoub, Sébastien Besset, Mohamed Ichchou
    Abstract:

    This paper is primarily focused on the identification of structural forces, with the objective of localizing forces injected into structures in the mid-high frequency range. An Energy Method, called the simplified Energy Method (MES), has already been introduced for the purpose of predicting an Energy density distribution for structural acoustic problems in the mid-high frequency range. The present paper proposes using this same Energy Method to solve inverse structural problems. More specifically, the injected forces are to be estimated and localized through knowledge of a set of Energy densities within the structure. The 2D formulation of this inverse approach, known as inverse MES (or IMES), is first expressed. Both the boundary and internal sources can then be detected by applying the proposed formulation. Numerical test results are processed using a 2D Kirchhoff plate, and a number of conclusions are also drawn regarding IMES capabilities. Moreover, this paper offers a numerical comparison with another Energy-based Method.

  • An inverse mid-high frequency Energy Method: Formulation and applications
    2010
    Co-Authors: Olivier Bareille, Mohamed Chabchoub, Sébastien Besset, Mohamed Ichchou
    Abstract:

    An Energy Method called Simplified Energy Method (MES) has already been proposed to predict Energy densities repartition for structural-acoustic problems in the mid-high frequency range. In order to illustrate but also to present one of the applications of this Method, this latter is used here to solve inverse structural problems. The main application, in this paper, is the structural forces identification thanks to Energy densities calculation and analysis. The injected forces estimation and localization are hence obtained in the mid-high frequency range. Internal as well as boundary sources are here detected through 2D Kirchhoff-plate numerical tests.

Johan Åqvist - One of the best experts on this subject based on the ideXlab platform.