The Experts below are selected from a list of 41532 Experts worldwide ranked by ideXlab platform
Emre Yüce - One of the best experts on this subject based on the ideXlab platform.
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Effective Bandwidth approach for the spectral splitting of solar spectrum using diffractive optical elements
Optics Express, 2020Co-Authors: Alim Yolalmaz, Emre YüceAbstract:Spectral splitting of the sunlight using diffractive optical elements (DOEs) is an Effective method to increase the efficiency of solar panels. Here, we design phase-only DOEs by using an iterative optimization algorithm to spectrally split and simultaneously concentrate solar spectrum. In our calculations, we take material dispersion into account as well as the normalized blackbody spectrum of the sunlight. The algorithm consists of the local search optimization and is strengthened with an outperforming logic operation called MEAN optimization. Using the MEAN optimization algorithm, we demonstrate spectral splitting of a dichromatic light source at 700 nm and 1100 nm with spectral splitting efficiencies of 92% and 94%, respectively. In this manuscript, we introduce an Effective Bandwidth approach, which reduces the computational time of DOEs from 89 days to 8 days, while preserving the spectral splitting efficiency. Using our Effective Bandwidth method, we manage to spectrally split light into two separate bands between 400 nm - 700 nm and 701 nm - 1100 nm, with splitting efficiencies of 56% and 63%, respectively. Our outperforming and Effective Bandwidth design approach can be applied to DOE designs in color holography, spectroscopy, and imaging applications.
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Effective Bandwidth approach for spectral splitting of solar spectrum using diffractive optical elements
Optics express, 2020Co-Authors: Alim Yolalmaz, Emre YüceAbstract:Spectral splitting of the sunlight using diffractive optical elements (DOEs) is an Effective method to increase the efficiency of solar panels. Here, we design phase-only DOEs by using an iterative optimization algorithm to spectrally split and simultaneously concentrate solar spectrum. In our calculations, we take material dispersion into account as well as the normalized blackbody spectrum of the sunlight. The algorithm consists of the local search optimization and is strengthen with an outperforming logic operation called MEAN optimization. Using the MEAN optimization algorithm, we demonstrate spectral splitting of a dichromatic light source at 700 nm and 1100 nm with spectral splitting efficiencies of 92% and 94%, respectively. In this manuscript, we introduce an Effective Bandwidth approach, which reduces the computation time of DOEs from 89 days to 8 days, while preserving the spectral splitting efficiency. Using our Effective Bandwidth method we manage to spectrally split light into two separate bands between 400 nm - 700 nm and 701 nm - 1100 nm, with splitting efficiencies of 56% and 63%, respectively. Our outperforming and Effective Bandwidth design approach can be applied to DOE designs in color holography, spectroscopy, and imaging applications.
Alim Yolalmaz - One of the best experts on this subject based on the ideXlab platform.
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Effective Bandwidth approach for the spectral splitting of solar spectrum using diffractive optical elements
Optics Express, 2020Co-Authors: Alim Yolalmaz, Emre YüceAbstract:Spectral splitting of the sunlight using diffractive optical elements (DOEs) is an Effective method to increase the efficiency of solar panels. Here, we design phase-only DOEs by using an iterative optimization algorithm to spectrally split and simultaneously concentrate solar spectrum. In our calculations, we take material dispersion into account as well as the normalized blackbody spectrum of the sunlight. The algorithm consists of the local search optimization and is strengthened with an outperforming logic operation called MEAN optimization. Using the MEAN optimization algorithm, we demonstrate spectral splitting of a dichromatic light source at 700 nm and 1100 nm with spectral splitting efficiencies of 92% and 94%, respectively. In this manuscript, we introduce an Effective Bandwidth approach, which reduces the computational time of DOEs from 89 days to 8 days, while preserving the spectral splitting efficiency. Using our Effective Bandwidth method, we manage to spectrally split light into two separate bands between 400 nm - 700 nm and 701 nm - 1100 nm, with splitting efficiencies of 56% and 63%, respectively. Our outperforming and Effective Bandwidth design approach can be applied to DOE designs in color holography, spectroscopy, and imaging applications.
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Effective Bandwidth approach for spectral splitting of solar spectrum using diffractive optical elements
Optics express, 2020Co-Authors: Alim Yolalmaz, Emre YüceAbstract:Spectral splitting of the sunlight using diffractive optical elements (DOEs) is an Effective method to increase the efficiency of solar panels. Here, we design phase-only DOEs by using an iterative optimization algorithm to spectrally split and simultaneously concentrate solar spectrum. In our calculations, we take material dispersion into account as well as the normalized blackbody spectrum of the sunlight. The algorithm consists of the local search optimization and is strengthen with an outperforming logic operation called MEAN optimization. Using the MEAN optimization algorithm, we demonstrate spectral splitting of a dichromatic light source at 700 nm and 1100 nm with spectral splitting efficiencies of 92% and 94%, respectively. In this manuscript, we introduce an Effective Bandwidth approach, which reduces the computation time of DOEs from 89 days to 8 days, while preserving the spectral splitting efficiency. Using our Effective Bandwidth method we manage to spectrally split light into two separate bands between 400 nm - 700 nm and 701 nm - 1100 nm, with splitting efficiencies of 56% and 63%, respectively. Our outperforming and Effective Bandwidth design approach can be applied to DOE designs in color holography, spectroscopy, and imaging applications.
Mohammed F Daqaq - One of the best experts on this subject based on the ideXlab platform.
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characterizing the Effective Bandwidth of tri stable energy harvesters
Journal of Sound and Vibration, 2017Co-Authors: Meghashyam Panyam, Mohammed F DaqaqAbstract:Abstract Recently, it has been shown that nonlinear vibratory energy harvesters possessing a tri-stable potential function are capable of harvesting energy efficiently over a wider range of frequencies in comparison to harvesters with a double-well potential function. However, the effect of the design parameters of the harvester on the dynamic response and the Effective Bandwidth of such devices remains uninvestigated. To fill this void, this paper establishes an analytical approach to characterize the Effective frequency Bandwidth of harvesters that possess a hexic potential energy function. To achieve this goal, the method of multiple scales is utilized to construct analytical solutions describing the amplitude and stability of the intra- and inter-well dynamics of the harvester. Using these solutions, critical bifurcations in the parameter's space are identified and used to define an Effective frequency Bandwidth of the harvester. The influence of the electric parameters, namely, the time constant ratio (ratio between the period of the mechanical system and the time constant of the harvesting circuit) and the electromechanical coupling, on the Effective frequency Bandwidth is analyzed. Experimental studies performed on the harvester are presented to validate some of the theoretical findings.
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on approximating the Effective Bandwidth of bi stable energy harvesters
International Journal of Non-linear Mechanics, 2014Co-Authors: Meghashyam Panyam, Ravindra Masana, Mohammed F DaqaqAbstract:Abstract This paper aims to establish an analytical framework to define the Effective Bandwidth of bi-stable vibratory energy harvesters possessing a symmetric quartic potential function. To achieve this goal, the method of multiple scales is utilized to construct analytical solutions describing the amplitude and stability of the intra- and inter-well dynamics of the harvester. Using these solutions, critical bifurcations in the parameters׳ space are identified and used to define an Effective frequency Bandwidth of the harvester. The influence of three critical design parameters, namely the time constant ratio (ratio between the time constant of the harvesting circuit and the period of the mechanical system), the electromechanical coupling, and the shape of the potential function, on the Effective frequency Bandwidth is analyzed. It is shown that, while the time constant ratio has very little influence on the Effective Bandwidth of the harvester, increasing the electromechanical coupling and/or designing the potential function with deeper potential wells serve to shrink the Effective Bandwidth for a given level of excitation. In general, it is also observed that narrowing of the Effective Bandwidth is accompanied by an increase in the electric output further highlighting the competing nature of these two desired objectives.
Meghashyam Panyam - One of the best experts on this subject based on the ideXlab platform.
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characterizing the Effective Bandwidth of tri stable energy harvesters
Journal of Sound and Vibration, 2017Co-Authors: Meghashyam Panyam, Mohammed F DaqaqAbstract:Abstract Recently, it has been shown that nonlinear vibratory energy harvesters possessing a tri-stable potential function are capable of harvesting energy efficiently over a wider range of frequencies in comparison to harvesters with a double-well potential function. However, the effect of the design parameters of the harvester on the dynamic response and the Effective Bandwidth of such devices remains uninvestigated. To fill this void, this paper establishes an analytical approach to characterize the Effective frequency Bandwidth of harvesters that possess a hexic potential energy function. To achieve this goal, the method of multiple scales is utilized to construct analytical solutions describing the amplitude and stability of the intra- and inter-well dynamics of the harvester. Using these solutions, critical bifurcations in the parameter's space are identified and used to define an Effective frequency Bandwidth of the harvester. The influence of the electric parameters, namely, the time constant ratio (ratio between the period of the mechanical system and the time constant of the harvesting circuit) and the electromechanical coupling, on the Effective frequency Bandwidth is analyzed. Experimental studies performed on the harvester are presented to validate some of the theoretical findings.
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on approximating the Effective Bandwidth of bi stable energy harvesters
International Journal of Non-linear Mechanics, 2014Co-Authors: Meghashyam Panyam, Ravindra Masana, Mohammed F DaqaqAbstract:Abstract This paper aims to establish an analytical framework to define the Effective Bandwidth of bi-stable vibratory energy harvesters possessing a symmetric quartic potential function. To achieve this goal, the method of multiple scales is utilized to construct analytical solutions describing the amplitude and stability of the intra- and inter-well dynamics of the harvester. Using these solutions, critical bifurcations in the parameters׳ space are identified and used to define an Effective frequency Bandwidth of the harvester. The influence of three critical design parameters, namely the time constant ratio (ratio between the time constant of the harvesting circuit and the period of the mechanical system), the electromechanical coupling, and the shape of the potential function, on the Effective frequency Bandwidth is analyzed. It is shown that, while the time constant ratio has very little influence on the Effective Bandwidth of the harvester, increasing the electromechanical coupling and/or designing the potential function with deeper potential wells serve to shrink the Effective Bandwidth for a given level of excitation. In general, it is also observed that narrowing of the Effective Bandwidth is accompanied by an increase in the electric output further highlighting the competing nature of these two desired objectives.
Avideh Zakhor - One of the best experts on this subject based on the ideXlab platform.
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Effective Bandwidth based scheduling for streaming media
IEEE Transactions on Multimedia, 2005Co-Authors: S. H. Kang, Avideh ZakhorAbstract:We propose a class of rate-distortion optimized packet scheduling algorithms for streaming media by generating a number of nested substreams, with more important streams embedding less important ones in a progressive manner. Our goal is to determine the optimum substream to send at any moment in time, using feedback information from the receiver and statistical characteristics of the video. To do so, we model the streaming system as a queueing system, compute the run-time decoding failure probability of a group of picture in each substream based on Effective Bandwidth approach, and determine the optimum substream to be sent at that moment in time. We evaluate our scheduling scheme with various video traffic models featuring short-range dependency (SRD), long-range dependency (LRD), and/or multifractal properties. From experiments with real video data, we show that our proposed scheduling scheme outperforms the conventional sequential sending scheme.
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Effective Bandwidth based scheduling for streaming multimedia
International Conference on Image Processing, 2003Co-Authors: S. H. Kang, Avideh ZakhorAbstract:We propose a class of packet scheduling algorithms for streaming media. The importance level of a video packet is determined by its relative position within its group of pictures, taking into account the motion-texture discrimination and temporal scalability. We generate a number of nested substreams, with more important streams embedding less important ones in a progressive manner. We model the streaming system as a queueing system, compute the run-time decoding failure probability of a frame in each substream based on Effective Bandwidth, and determine the optimum substream to be sent at any moment in time. The data within optimum substream is sent based on earliest-deadline-first scheduling, until the next channel report arrives, at which time the optimum substream is recomputed. From experiments with real video data, we show that our proposed scheduling scheme outperforms the conventional sequential sending scheme.
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ICIP (3) - Effective Bandwidth based scheduling for streaming multimedia
Proceedings 2003 International Conference on Image Processing (Cat. No.03CH37429), 2003Co-Authors: S. H. Kang, Avideh ZakhorAbstract:We propose a class of packet scheduling algorithms for streaming media. The importance level of a video packet is determined by its relative position within its group of pictures, taking into account the motion-texture discrimination and temporal scalability. We generate a number of nested substreams, with more important streams embedding less important ones in a progressive manner. We model the streaming system as a queueing system, compute the run-time decoding failure probability of a frame in each substream based on Effective Bandwidth, and determine the optimum substream to be sent at any moment in time. The data within optimum substream is sent based on earliest-deadline-first scheduling, until the next channel report arrives, at which time the optimum substream is recomputed. From experiments with real video data, we show that our proposed scheduling scheme outperforms the conventional sequential sending scheme.