The Experts below are selected from a list of 177 Experts worldwide ranked by ideXlab platform
Jose Moreno - One of the best experts on this subject based on the ideXlab platform.
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Comparative analysis of atmospheric radiative transfer models using the Atmospheric Look-up Table Generator (ALG) toolbox (version 2.0)
Geoscientific Model Development, 2020Co-Authors: Jorge Vicent, Jochem Verrelst, Neus Sabater, Luis Alonso, Juan Pablo Rivera-caicedo, Luca Martino, Jordi Muñoz-marí, Jose MorenoAbstract:Abstract. Atmospheric radiative transfer models (RTMs) are software tools that help researchers in understanding the radiative processes occurring in the Earth's atmosphere. Given their importance in remote sensing applications, the intercomparison of atmospheric RTMs is therefore one of the main tasks used to evaluate model performance and identify the characteristics that differ between models. This can be a tedious tasks that requires good knowledge of the model inputs/outputs and the generation of large databases of consistent simulations. With the evolution of these software tools, their increase in complexity bears implications for their use in practical applications and model intercomparison. Existing RTM-specific graphical user interfaces are not optimized for performing intercomparison studies of a wide variety of atmospheric RTMs. In this paper, we present the Atmospheric Look-up Table Generator (ALG) version 2.0, a new software tool that facilitates generating large databases for a variety of atmospheric RTMs. ALG facilitates consistent and intuitive user interaction to enable the running of model executions and storing of RTM data for any spectral configuration in the optical domain. We demonstrate the utility of ALG in performing intercomparison studies of radiance simulations from broadly used atmospheric RTMs (6SV, MODTRAN, and libRadtran) through global sensitivity analysis. We expect that providing ALG to the research community will facilitate the usage of atmospheric RTMs to a wide range of applications in Earth observation.
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Comparative analysis of atmospheric radiative transfer models using the Atmospheric Look-up Table Generator (ALG) toolbox (version 2.0)
2019Co-Authors: Jorge Vicent, Jochem Verrelst, Neus Sabater, Luis Alonso, Juan Pablo Rivera-caicedo, Luca Martino, Jordi Muñoz-marí, Jose MorenoAbstract:Abstract. Atmospheric radiative transfer models (RTMs) are software tools that help researchers in understanding the radiative processes occurring in the Earth’s atmosphere. Given their importance in remote sensing applications, the intercomparison of atmospheric RTMs is therefore one of the main tasks to evaluate model performance and identify the characteristics that differ between models. This can be a tedious tasks that requires a good knowledge of the model inputs-outputs and generation of large databases of consistent simulations. With the evolution of these software tools, their increase in complexity bears implications towards their use in practical applications and model intercomparison. Existing RTM-specific graphical user interfaces are not optimized for performing intercomparison studies of a wide variety of atmospheric RTMs. In this paper, we present the Atmospheric Look-up Table Generator (ALG) version 2.0, a new software tool that facilitates generating large databases for a variety of atmospheric RTMs. ALG facilitates consistent and intuitive user interaction to enable running model executions and storing RTM data for any spectral configuration in the optical domain. We demonstrate the utility of ALG to perform intercomparison studies and global sensitivity analysis of broadly used atmospheric RTMs (6SV, MODTRAN, libRadtran). We expect that providing ALG to the research community will facilitate the usage of atmospheric RTMs to a wide range of applications in Earth Observation.
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Gradient-Based Automatic Lookup Table Generator for Radiative Transfer Models
IEEE Transactions on Geoscience and Remote Sensing, 2019Co-Authors: Jorge Vicent Servera, Jochem Verrelst, Neus Sabater, Luis Alonso, Luca Martino, Gustau Camps-valls, Jose MorenoAbstract:Physically based radiative transfer models (RTMs) are widely used in Earth observation to understand the radiation processes occurring on the Earth’s surface and their interactions with water, vegetation, and atmosphere. Through continuous improvements, RTMs have increased in accuracy and representativity of complex scenes at expenses of an increase in complexity and computation time, making them impractical in various remote sensing applications. To overcome this limitation, the common practice is to precompute large lookup Tables (LUTs) for their later interpolation. To further reduce the RTM computation burden and the error in LUT interpolation, we have developed a method to automatically select the minimum and optimal set of input–output points (nodes) to be included in an LUT. We present the gradient-based automatic LUT Generator algorithm (GALGA), which relies on the notion of an acquisition function that incorporates: 1) the Jacobian evaluation of an RTM and 2) the information about the multivariate distribution of the current nodes. We illustrate the capabilities of GALGA in the automatic construction and optimization of MODTRAN-based LUTs of different dimensions of the input variables space. Our results indicate that when compared with a pseudorandom homogeneous distribution of the LUT nodes, GALGA reduces: 1) the LUT size by >24%; 2) the computation time by ~27%; and 3) the maximum interpolation relative errors by at least 10%. It is concluded that an automatic LUT design might benefit from the methodology proposed in GALGA to reduce interpolation errors and computation time in computationally expensive RTMs.
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WHISPERS - Alg: a Toolbox for the Generation of Look-Up Tables Based on Atmospheric Radiative Transfer Models
2018 9th Workshop on Hyperspectral Image and Signal Processing: Evolution in Remote Sensing (WHISPERS), 2018Co-Authors: Jorge Vicent, Jochem Verrelst, Neus Sabater, Luis Alonso, Jose MorenoAbstract:Atmospheric radiative transfer models (RTMs) are software tools describing the radiation processes occurring on the Earth’s atmosphere. While the evolution of these tools have achieved better representations of the light-atmosphere interactions, the increase of complexity, interpretability and computation time bears implications towards practical applications in Earth observation. Despite of existing RTM-specific graphical user interfaces, none of these tools allow common streamlining model setup for a wide variety of atmospheric RTMs. In addition, the automatic generation of atmospheric look-up Tables (LUTs) can hardly be done with the use of these graphical tools. This paper presents the Atmospheric Look-up Table Generator (ALG, v1.2), a new software tool to generate and to analyze LUTs based on a suite of atmospheric RTMs. It facilitates consistent and intuitive user interaction for running model executions and storing RTM data for any spectral configuration in the optical domain. We demonstrate the utility and versatility of ALG to facilitate research on atmospheric radiative transfer, as well as opening the use of atmospheric RTMs to a wide range of applications.
Myoung Hwan Choi - One of the best experts on this subject based on the ideXlab platform.
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A real-time traffic control scheme of multiple AGV systems for collision free minimum time motion: a routing Table approach
IEEE Transactions on Systems Man and Cybernetics - Part A: Systems and Humans, 1998Co-Authors: Jung Hoon Lee, Beom Hee Lee, Myoung Hwan ChoiAbstract:A two-staged traffic control scheme, in which sets of candidate paths are prepared off-line prior to overall motion planning process, has been widely adopted for motion planning of mobile robots, but relatively little attention has been given to the application of the two-staged scheme to multiple automated guided vehicle systems (MAGVSs). In the paper, a systematic two-staged traffic control scheme is presented to obtain collision-free minimum-time motions of AGVs along loopless paths. The overall structure of the controller is divided into two tandem modules of off-line routing Table Generator (RTG) and an online traffic controller (OTC). First, an induced network model is established considering the configurational restrictions of guide-paths. With this model and a modified k-shortest path algorithm, RTG finds sets of k candidate paths from each station nodes to all the other station nodes off-line and stores them in the form of routing Tables. Each time a dispatch command for an AGV is issued, OTC utilizes these routing Tables to generate a collision-free minimum-time motion along a loopless path. Real-time computation is guaranteed in that the time-consuming graph searching process is executed off-line by RTG, and OTC looks for the minimum time motion among the k candidate paths. The traffic control scheme proposed is suiTable for practical application in centralized MAGVS with zone blocking technique.
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A routing Table approach for minimum time traffic control of multiple AGV systems
Proceedings of the IECON'97 23rd International Conference on Industrial Electronics Control and Instrumentation (Cat. No.97CH36066), 1Co-Authors: Jung Hoon Lee, Beom Hee Lee, Myoung Hwan ChoiAbstract:A two-staged scheme, in which the path determination stage is divided from the overall motion planning process and performed offline, has been widely adopted for the motion planning of mobile robots. However, relatively little attention has been given to the application of the two-staged scheme to multiple automated guided vehicle systems (MAGVS). In this paper, a systematic two-staged scheme is presented to obtain collision-free minimum-time motions of AGVs along loopless paths. The overall structure of the controller is divided into two tandem modules of an offline routing Table Generator (RTG) and an online traffic controller (OTC). Real-time computation is guaranteed in that time-consuming graph searching process is executed offline, and OTC looks for the minimum time motion among the k candidate paths. The traffic control scheme proposed is suiTable for practical application in centralized MAGVS with zone blocking technique.
Neus Sabater - One of the best experts on this subject based on the ideXlab platform.
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Comparative analysis of atmospheric radiative transfer models using the Atmospheric Look-up Table Generator (ALG) toolbox (version 2.0)
Geoscientific Model Development, 2020Co-Authors: Jorge Vicent, Jochem Verrelst, Neus Sabater, Luis Alonso, Juan Pablo Rivera-caicedo, Luca Martino, Jordi Muñoz-marí, Jose MorenoAbstract:Abstract. Atmospheric radiative transfer models (RTMs) are software tools that help researchers in understanding the radiative processes occurring in the Earth's atmosphere. Given their importance in remote sensing applications, the intercomparison of atmospheric RTMs is therefore one of the main tasks used to evaluate model performance and identify the characteristics that differ between models. This can be a tedious tasks that requires good knowledge of the model inputs/outputs and the generation of large databases of consistent simulations. With the evolution of these software tools, their increase in complexity bears implications for their use in practical applications and model intercomparison. Existing RTM-specific graphical user interfaces are not optimized for performing intercomparison studies of a wide variety of atmospheric RTMs. In this paper, we present the Atmospheric Look-up Table Generator (ALG) version 2.0, a new software tool that facilitates generating large databases for a variety of atmospheric RTMs. ALG facilitates consistent and intuitive user interaction to enable the running of model executions and storing of RTM data for any spectral configuration in the optical domain. We demonstrate the utility of ALG in performing intercomparison studies of radiance simulations from broadly used atmospheric RTMs (6SV, MODTRAN, and libRadtran) through global sensitivity analysis. We expect that providing ALG to the research community will facilitate the usage of atmospheric RTMs to a wide range of applications in Earth observation.
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Comparative analysis of atmospheric radiative transfer models using the Atmospheric Look-up Table Generator (ALG) toolbox (version 2.0)
2019Co-Authors: Jorge Vicent, Jochem Verrelst, Neus Sabater, Luis Alonso, Juan Pablo Rivera-caicedo, Luca Martino, Jordi Muñoz-marí, Jose MorenoAbstract:Abstract. Atmospheric radiative transfer models (RTMs) are software tools that help researchers in understanding the radiative processes occurring in the Earth’s atmosphere. Given their importance in remote sensing applications, the intercomparison of atmospheric RTMs is therefore one of the main tasks to evaluate model performance and identify the characteristics that differ between models. This can be a tedious tasks that requires a good knowledge of the model inputs-outputs and generation of large databases of consistent simulations. With the evolution of these software tools, their increase in complexity bears implications towards their use in practical applications and model intercomparison. Existing RTM-specific graphical user interfaces are not optimized for performing intercomparison studies of a wide variety of atmospheric RTMs. In this paper, we present the Atmospheric Look-up Table Generator (ALG) version 2.0, a new software tool that facilitates generating large databases for a variety of atmospheric RTMs. ALG facilitates consistent and intuitive user interaction to enable running model executions and storing RTM data for any spectral configuration in the optical domain. We demonstrate the utility of ALG to perform intercomparison studies and global sensitivity analysis of broadly used atmospheric RTMs (6SV, MODTRAN, libRadtran). We expect that providing ALG to the research community will facilitate the usage of atmospheric RTMs to a wide range of applications in Earth Observation.
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Gradient-Based Automatic Lookup Table Generator for Radiative Transfer Models
IEEE Transactions on Geoscience and Remote Sensing, 2019Co-Authors: Jorge Vicent Servera, Jochem Verrelst, Neus Sabater, Luis Alonso, Luca Martino, Gustau Camps-valls, Jose MorenoAbstract:Physically based radiative transfer models (RTMs) are widely used in Earth observation to understand the radiation processes occurring on the Earth’s surface and their interactions with water, vegetation, and atmosphere. Through continuous improvements, RTMs have increased in accuracy and representativity of complex scenes at expenses of an increase in complexity and computation time, making them impractical in various remote sensing applications. To overcome this limitation, the common practice is to precompute large lookup Tables (LUTs) for their later interpolation. To further reduce the RTM computation burden and the error in LUT interpolation, we have developed a method to automatically select the minimum and optimal set of input–output points (nodes) to be included in an LUT. We present the gradient-based automatic LUT Generator algorithm (GALGA), which relies on the notion of an acquisition function that incorporates: 1) the Jacobian evaluation of an RTM and 2) the information about the multivariate distribution of the current nodes. We illustrate the capabilities of GALGA in the automatic construction and optimization of MODTRAN-based LUTs of different dimensions of the input variables space. Our results indicate that when compared with a pseudorandom homogeneous distribution of the LUT nodes, GALGA reduces: 1) the LUT size by >24%; 2) the computation time by ~27%; and 3) the maximum interpolation relative errors by at least 10%. It is concluded that an automatic LUT design might benefit from the methodology proposed in GALGA to reduce interpolation errors and computation time in computationally expensive RTMs.
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WHISPERS - Alg: a Toolbox for the Generation of Look-Up Tables Based on Atmospheric Radiative Transfer Models
2018 9th Workshop on Hyperspectral Image and Signal Processing: Evolution in Remote Sensing (WHISPERS), 2018Co-Authors: Jorge Vicent, Jochem Verrelst, Neus Sabater, Luis Alonso, Jose MorenoAbstract:Atmospheric radiative transfer models (RTMs) are software tools describing the radiation processes occurring on the Earth’s atmosphere. While the evolution of these tools have achieved better representations of the light-atmosphere interactions, the increase of complexity, interpretability and computation time bears implications towards practical applications in Earth observation. Despite of existing RTM-specific graphical user interfaces, none of these tools allow common streamlining model setup for a wide variety of atmospheric RTMs. In addition, the automatic generation of atmospheric look-up Tables (LUTs) can hardly be done with the use of these graphical tools. This paper presents the Atmospheric Look-up Table Generator (ALG, v1.2), a new software tool to generate and to analyze LUTs based on a suite of atmospheric RTMs. It facilitates consistent and intuitive user interaction for running model executions and storing RTM data for any spectral configuration in the optical domain. We demonstrate the utility and versatility of ALG to facilitate research on atmospheric radiative transfer, as well as opening the use of atmospheric RTMs to a wide range of applications.
Luis Alonso - One of the best experts on this subject based on the ideXlab platform.
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Comparative analysis of atmospheric radiative transfer models using the Atmospheric Look-up Table Generator (ALG) toolbox (version 2.0)
Geoscientific Model Development, 2020Co-Authors: Jorge Vicent, Jochem Verrelst, Neus Sabater, Luis Alonso, Juan Pablo Rivera-caicedo, Luca Martino, Jordi Muñoz-marí, Jose MorenoAbstract:Abstract. Atmospheric radiative transfer models (RTMs) are software tools that help researchers in understanding the radiative processes occurring in the Earth's atmosphere. Given their importance in remote sensing applications, the intercomparison of atmospheric RTMs is therefore one of the main tasks used to evaluate model performance and identify the characteristics that differ between models. This can be a tedious tasks that requires good knowledge of the model inputs/outputs and the generation of large databases of consistent simulations. With the evolution of these software tools, their increase in complexity bears implications for their use in practical applications and model intercomparison. Existing RTM-specific graphical user interfaces are not optimized for performing intercomparison studies of a wide variety of atmospheric RTMs. In this paper, we present the Atmospheric Look-up Table Generator (ALG) version 2.0, a new software tool that facilitates generating large databases for a variety of atmospheric RTMs. ALG facilitates consistent and intuitive user interaction to enable the running of model executions and storing of RTM data for any spectral configuration in the optical domain. We demonstrate the utility of ALG in performing intercomparison studies of radiance simulations from broadly used atmospheric RTMs (6SV, MODTRAN, and libRadtran) through global sensitivity analysis. We expect that providing ALG to the research community will facilitate the usage of atmospheric RTMs to a wide range of applications in Earth observation.
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Comparative analysis of atmospheric radiative transfer models using the Atmospheric Look-up Table Generator (ALG) toolbox (version 2.0)
2019Co-Authors: Jorge Vicent, Jochem Verrelst, Neus Sabater, Luis Alonso, Juan Pablo Rivera-caicedo, Luca Martino, Jordi Muñoz-marí, Jose MorenoAbstract:Abstract. Atmospheric radiative transfer models (RTMs) are software tools that help researchers in understanding the radiative processes occurring in the Earth’s atmosphere. Given their importance in remote sensing applications, the intercomparison of atmospheric RTMs is therefore one of the main tasks to evaluate model performance and identify the characteristics that differ between models. This can be a tedious tasks that requires a good knowledge of the model inputs-outputs and generation of large databases of consistent simulations. With the evolution of these software tools, their increase in complexity bears implications towards their use in practical applications and model intercomparison. Existing RTM-specific graphical user interfaces are not optimized for performing intercomparison studies of a wide variety of atmospheric RTMs. In this paper, we present the Atmospheric Look-up Table Generator (ALG) version 2.0, a new software tool that facilitates generating large databases for a variety of atmospheric RTMs. ALG facilitates consistent and intuitive user interaction to enable running model executions and storing RTM data for any spectral configuration in the optical domain. We demonstrate the utility of ALG to perform intercomparison studies and global sensitivity analysis of broadly used atmospheric RTMs (6SV, MODTRAN, libRadtran). We expect that providing ALG to the research community will facilitate the usage of atmospheric RTMs to a wide range of applications in Earth Observation.
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Gradient-Based Automatic Lookup Table Generator for Radiative Transfer Models
IEEE Transactions on Geoscience and Remote Sensing, 2019Co-Authors: Jorge Vicent Servera, Jochem Verrelst, Neus Sabater, Luis Alonso, Luca Martino, Gustau Camps-valls, Jose MorenoAbstract:Physically based radiative transfer models (RTMs) are widely used in Earth observation to understand the radiation processes occurring on the Earth’s surface and their interactions with water, vegetation, and atmosphere. Through continuous improvements, RTMs have increased in accuracy and representativity of complex scenes at expenses of an increase in complexity and computation time, making them impractical in various remote sensing applications. To overcome this limitation, the common practice is to precompute large lookup Tables (LUTs) for their later interpolation. To further reduce the RTM computation burden and the error in LUT interpolation, we have developed a method to automatically select the minimum and optimal set of input–output points (nodes) to be included in an LUT. We present the gradient-based automatic LUT Generator algorithm (GALGA), which relies on the notion of an acquisition function that incorporates: 1) the Jacobian evaluation of an RTM and 2) the information about the multivariate distribution of the current nodes. We illustrate the capabilities of GALGA in the automatic construction and optimization of MODTRAN-based LUTs of different dimensions of the input variables space. Our results indicate that when compared with a pseudorandom homogeneous distribution of the LUT nodes, GALGA reduces: 1) the LUT size by >24%; 2) the computation time by ~27%; and 3) the maximum interpolation relative errors by at least 10%. It is concluded that an automatic LUT design might benefit from the methodology proposed in GALGA to reduce interpolation errors and computation time in computationally expensive RTMs.
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WHISPERS - Alg: a Toolbox for the Generation of Look-Up Tables Based on Atmospheric Radiative Transfer Models
2018 9th Workshop on Hyperspectral Image and Signal Processing: Evolution in Remote Sensing (WHISPERS), 2018Co-Authors: Jorge Vicent, Jochem Verrelst, Neus Sabater, Luis Alonso, Jose MorenoAbstract:Atmospheric radiative transfer models (RTMs) are software tools describing the radiation processes occurring on the Earth’s atmosphere. While the evolution of these tools have achieved better representations of the light-atmosphere interactions, the increase of complexity, interpretability and computation time bears implications towards practical applications in Earth observation. Despite of existing RTM-specific graphical user interfaces, none of these tools allow common streamlining model setup for a wide variety of atmospheric RTMs. In addition, the automatic generation of atmospheric look-up Tables (LUTs) can hardly be done with the use of these graphical tools. This paper presents the Atmospheric Look-up Table Generator (ALG, v1.2), a new software tool to generate and to analyze LUTs based on a suite of atmospheric RTMs. It facilitates consistent and intuitive user interaction for running model executions and storing RTM data for any spectral configuration in the optical domain. We demonstrate the utility and versatility of ALG to facilitate research on atmospheric radiative transfer, as well as opening the use of atmospheric RTMs to a wide range of applications.
Jochem Verrelst - One of the best experts on this subject based on the ideXlab platform.
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Comparative analysis of atmospheric radiative transfer models using the Atmospheric Look-up Table Generator (ALG) toolbox (version 2.0)
Geoscientific Model Development, 2020Co-Authors: Jorge Vicent, Jochem Verrelst, Neus Sabater, Luis Alonso, Juan Pablo Rivera-caicedo, Luca Martino, Jordi Muñoz-marí, Jose MorenoAbstract:Abstract. Atmospheric radiative transfer models (RTMs) are software tools that help researchers in understanding the radiative processes occurring in the Earth's atmosphere. Given their importance in remote sensing applications, the intercomparison of atmospheric RTMs is therefore one of the main tasks used to evaluate model performance and identify the characteristics that differ between models. This can be a tedious tasks that requires good knowledge of the model inputs/outputs and the generation of large databases of consistent simulations. With the evolution of these software tools, their increase in complexity bears implications for their use in practical applications and model intercomparison. Existing RTM-specific graphical user interfaces are not optimized for performing intercomparison studies of a wide variety of atmospheric RTMs. In this paper, we present the Atmospheric Look-up Table Generator (ALG) version 2.0, a new software tool that facilitates generating large databases for a variety of atmospheric RTMs. ALG facilitates consistent and intuitive user interaction to enable the running of model executions and storing of RTM data for any spectral configuration in the optical domain. We demonstrate the utility of ALG in performing intercomparison studies of radiance simulations from broadly used atmospheric RTMs (6SV, MODTRAN, and libRadtran) through global sensitivity analysis. We expect that providing ALG to the research community will facilitate the usage of atmospheric RTMs to a wide range of applications in Earth observation.
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Comparative analysis of atmospheric radiative transfer models using the Atmospheric Look-up Table Generator (ALG) toolbox (version 2.0)
2019Co-Authors: Jorge Vicent, Jochem Verrelst, Neus Sabater, Luis Alonso, Juan Pablo Rivera-caicedo, Luca Martino, Jordi Muñoz-marí, Jose MorenoAbstract:Abstract. Atmospheric radiative transfer models (RTMs) are software tools that help researchers in understanding the radiative processes occurring in the Earth’s atmosphere. Given their importance in remote sensing applications, the intercomparison of atmospheric RTMs is therefore one of the main tasks to evaluate model performance and identify the characteristics that differ between models. This can be a tedious tasks that requires a good knowledge of the model inputs-outputs and generation of large databases of consistent simulations. With the evolution of these software tools, their increase in complexity bears implications towards their use in practical applications and model intercomparison. Existing RTM-specific graphical user interfaces are not optimized for performing intercomparison studies of a wide variety of atmospheric RTMs. In this paper, we present the Atmospheric Look-up Table Generator (ALG) version 2.0, a new software tool that facilitates generating large databases for a variety of atmospheric RTMs. ALG facilitates consistent and intuitive user interaction to enable running model executions and storing RTM data for any spectral configuration in the optical domain. We demonstrate the utility of ALG to perform intercomparison studies and global sensitivity analysis of broadly used atmospheric RTMs (6SV, MODTRAN, libRadtran). We expect that providing ALG to the research community will facilitate the usage of atmospheric RTMs to a wide range of applications in Earth Observation.
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Gradient-Based Automatic Lookup Table Generator for Radiative Transfer Models
IEEE Transactions on Geoscience and Remote Sensing, 2019Co-Authors: Jorge Vicent Servera, Jochem Verrelst, Neus Sabater, Luis Alonso, Luca Martino, Gustau Camps-valls, Jose MorenoAbstract:Physically based radiative transfer models (RTMs) are widely used in Earth observation to understand the radiation processes occurring on the Earth’s surface and their interactions with water, vegetation, and atmosphere. Through continuous improvements, RTMs have increased in accuracy and representativity of complex scenes at expenses of an increase in complexity and computation time, making them impractical in various remote sensing applications. To overcome this limitation, the common practice is to precompute large lookup Tables (LUTs) for their later interpolation. To further reduce the RTM computation burden and the error in LUT interpolation, we have developed a method to automatically select the minimum and optimal set of input–output points (nodes) to be included in an LUT. We present the gradient-based automatic LUT Generator algorithm (GALGA), which relies on the notion of an acquisition function that incorporates: 1) the Jacobian evaluation of an RTM and 2) the information about the multivariate distribution of the current nodes. We illustrate the capabilities of GALGA in the automatic construction and optimization of MODTRAN-based LUTs of different dimensions of the input variables space. Our results indicate that when compared with a pseudorandom homogeneous distribution of the LUT nodes, GALGA reduces: 1) the LUT size by >24%; 2) the computation time by ~27%; and 3) the maximum interpolation relative errors by at least 10%. It is concluded that an automatic LUT design might benefit from the methodology proposed in GALGA to reduce interpolation errors and computation time in computationally expensive RTMs.
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WHISPERS - Alg: a Toolbox for the Generation of Look-Up Tables Based on Atmospheric Radiative Transfer Models
2018 9th Workshop on Hyperspectral Image and Signal Processing: Evolution in Remote Sensing (WHISPERS), 2018Co-Authors: Jorge Vicent, Jochem Verrelst, Neus Sabater, Luis Alonso, Jose MorenoAbstract:Atmospheric radiative transfer models (RTMs) are software tools describing the radiation processes occurring on the Earth’s atmosphere. While the evolution of these tools have achieved better representations of the light-atmosphere interactions, the increase of complexity, interpretability and computation time bears implications towards practical applications in Earth observation. Despite of existing RTM-specific graphical user interfaces, none of these tools allow common streamlining model setup for a wide variety of atmospheric RTMs. In addition, the automatic generation of atmospheric look-up Tables (LUTs) can hardly be done with the use of these graphical tools. This paper presents the Atmospheric Look-up Table Generator (ALG, v1.2), a new software tool to generate and to analyze LUTs based on a suite of atmospheric RTMs. It facilitates consistent and intuitive user interaction for running model executions and storing RTM data for any spectral configuration in the optical domain. We demonstrate the utility and versatility of ALG to facilitate research on atmospheric radiative transfer, as well as opening the use of atmospheric RTMs to a wide range of applications.
