The Experts below are selected from a list of 183 Experts worldwide ranked by ideXlab platform
Shinobu Yoshimura - One of the best experts on this subject based on the ideXlab platform.
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Multidimensional visualization and clustering for multiobjective optimization of Artificial Satellite heat pipe design
Journal of Mechanical Science and Technology, 2007Co-Authors: Min Joong Jeong, Takashi Kobayashi, Shinobu YoshimuraAbstract:This study presents a newly developed approach for visualization of Pareto and quasi-Pareto solutions of a multiobjective design problem for the heat piping system in an Artificial Satellite. Given conflicting objective functions, multiobjective optimization requires both a search algorithm to find optimal solutions and a decision-making process for finalizing a design solution. This type of multiobjective optimization problem may easily induce equally optimized multple solutions such as Pareto solutions, quasi-Pareto solutions, and feasible solutions. Here, a multidimensional visualization and clustering technique is used for visualization of Pareto solutions. The proposed approach can support engineering decisions in the design of the heat piping system in Artificial Satellites. Design considerations for heat piping system need to simultaneously satisfy dual conditions such as thermal robustness and overall limitation of the total weight of the system. The proposed visualization and clustering technique can be a valuable design tool for the heat piping system, in which reliable decision-making has been frequently hindered by the conflicting nature of objective functions in conventional approaches.
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EMO - Extraction of design characteristics of multiobjective optimization – its application to design of Artificial Satellite heat pipe
Lecture Notes in Computer Science, 2005Co-Authors: Min Joong Jeong, Takashi Kobayashi, Shinobu YoshimuraAbstract:An Artificial Satellite design requires severe design objectives such as performance, reliability, weight, robustness, cost, and so on. To solve the conflicted requirements at the same time, multiobjective optimization is getting more popular in the design. Using the optimization, it becomes ordinary to get many solutions, such as Pareto solutions, quasi-Pareto solutions, and feasible solutions. The alternative solutions, however, are very difficult to be adopted to practical engineering decision directly. Therefore, to make the decision, proper information about the solutions in a function, parameter and real design space should be provided. In this paper, a new approach for the interpretation of Pareto solutions is proposed based on multidimensional visualization and clustering. The proposed method is applied to a thermal robustness and mass optimization problem of heat pipe shape design for an Artificial Satellite. The information gleaned from the propose approach can support the engineering decision for the design of Artificial Satellite heat pipe.
Min Joong Jeong - One of the best experts on this subject based on the ideXlab platform.
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Multidimensional visualization and clustering for multiobjective optimization of Artificial Satellite heat pipe design
Journal of Mechanical Science and Technology, 2007Co-Authors: Min Joong Jeong, Takashi Kobayashi, Shinobu YoshimuraAbstract:This study presents a newly developed approach for visualization of Pareto and quasi-Pareto solutions of a multiobjective design problem for the heat piping system in an Artificial Satellite. Given conflicting objective functions, multiobjective optimization requires both a search algorithm to find optimal solutions and a decision-making process for finalizing a design solution. This type of multiobjective optimization problem may easily induce equally optimized multple solutions such as Pareto solutions, quasi-Pareto solutions, and feasible solutions. Here, a multidimensional visualization and clustering technique is used for visualization of Pareto solutions. The proposed approach can support engineering decisions in the design of the heat piping system in Artificial Satellites. Design considerations for heat piping system need to simultaneously satisfy dual conditions such as thermal robustness and overall limitation of the total weight of the system. The proposed visualization and clustering technique can be a valuable design tool for the heat piping system, in which reliable decision-making has been frequently hindered by the conflicting nature of objective functions in conventional approaches.
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EMO - Extraction of design characteristics of multiobjective optimization – its application to design of Artificial Satellite heat pipe
Lecture Notes in Computer Science, 2005Co-Authors: Min Joong Jeong, Takashi Kobayashi, Shinobu YoshimuraAbstract:An Artificial Satellite design requires severe design objectives such as performance, reliability, weight, robustness, cost, and so on. To solve the conflicted requirements at the same time, multiobjective optimization is getting more popular in the design. Using the optimization, it becomes ordinary to get many solutions, such as Pareto solutions, quasi-Pareto solutions, and feasible solutions. The alternative solutions, however, are very difficult to be adopted to practical engineering decision directly. Therefore, to make the decision, proper information about the solutions in a function, parameter and real design space should be provided. In this paper, a new approach for the interpretation of Pareto solutions is proposed based on multidimensional visualization and clustering. The proposed method is applied to a thermal robustness and mass optimization problem of heat pipe shape design for an Artificial Satellite. The information gleaned from the propose approach can support the engineering decision for the design of Artificial Satellite heat pipe.
Antonio Fernando Bertachini De Almeida Prado - One of the best experts on this subject based on the ideXlab platform.
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onboard and real time Artificial Satellite orbit determination using gps
Mathematical Problems in Engineering, 2013Co-Authors: A P M Chiaradia, Helio Koiti Kuga, Antonio Fernando Bertachini De Almeida PradoAbstract:An algorithm for real-time and onboard orbit determination applying the Extended Kalman Filter (EKF) method is developed. Aiming at a very simple and still fairly accurate orbit determination, an analysis is performed to ascertain an adequacy of modeling complexity versus accuracy. The minimum set of to-be-estimated states to reach the level of accuracy of tens of meters is found to have at least the position, velocity, and user clock offset components. The dynamical model is assessed through several tests, covering force model, numerical integration scheme and step size, and simplified variational equations. The measurement model includes only relevant effects to the order of meters. The EKF method is chosen to be the simplest real-time estimation algorithm with adequate tuning of its parameters. In the developed procedure, the obtained position and velocity errors along a day vary from 15 to 20 m and from 0.014 to 0.018 m/s, respectively, with standard deviation from 6 to 10 m and from 0.006 to 0.008 m/s, respectively, with the SA either on or off. The results, as well as analysis of the final adopted models used, are presented in this work.
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single frequency gps measurements in real time Artificial Satellite orbit determination
Acta Astronautica, 2003Co-Authors: A P M Chiaradia, Helio Koiti Kuga, Antonio Fernando Bertachini De Almeida PradoAbstract:Abstract A simplified and compact algorithm with low computational cost providing an accuracy around tens of meters for Artificial Satellite orbit determination in real-time and on-board is developed in this work. The state estimation method is the extended Kalman filter. The Cowell's method is used to propagate the state vector, through a simple Runge–Kutta numerical integrator of fourth order with fixed step size. The modeled forces are due to the geopotential up to 50th order and degree of JGM-2 model. To time-update the state error covariance matrix, it is considered a simplified force model. In other words, in computing the state transition matrix, the effect of J2 (Earth flattening) is analytically considered, which unloads dramatically the processing time. In the measurement model, the single frequency GPS pseudorange is used, considering the effects of the ionospheric delay, clock offsets of the GPS and user Satellites, and relativistic effects. To validate this model, real live data are used from Topex/Poseidon Satellite and the results are compared with the Topex/Poseidon Precision Orbit Ephemeris (POE) generated by NASA/JPL, for several test cases. It is concluded that this compact algorithm enables accuracies of tens of meters with such simplified force model, analytical approach for computing the transition matrix, and a cheap GPS receiver providing single frequency pseudorange measurements.
Takashi Kobayashi - One of the best experts on this subject based on the ideXlab platform.
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Multidimensional visualization and clustering for multiobjective optimization of Artificial Satellite heat pipe design
Journal of Mechanical Science and Technology, 2007Co-Authors: Min Joong Jeong, Takashi Kobayashi, Shinobu YoshimuraAbstract:This study presents a newly developed approach for visualization of Pareto and quasi-Pareto solutions of a multiobjective design problem for the heat piping system in an Artificial Satellite. Given conflicting objective functions, multiobjective optimization requires both a search algorithm to find optimal solutions and a decision-making process for finalizing a design solution. This type of multiobjective optimization problem may easily induce equally optimized multple solutions such as Pareto solutions, quasi-Pareto solutions, and feasible solutions. Here, a multidimensional visualization and clustering technique is used for visualization of Pareto solutions. The proposed approach can support engineering decisions in the design of the heat piping system in Artificial Satellites. Design considerations for heat piping system need to simultaneously satisfy dual conditions such as thermal robustness and overall limitation of the total weight of the system. The proposed visualization and clustering technique can be a valuable design tool for the heat piping system, in which reliable decision-making has been frequently hindered by the conflicting nature of objective functions in conventional approaches.
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EMO - Extraction of design characteristics of multiobjective optimization – its application to design of Artificial Satellite heat pipe
Lecture Notes in Computer Science, 2005Co-Authors: Min Joong Jeong, Takashi Kobayashi, Shinobu YoshimuraAbstract:An Artificial Satellite design requires severe design objectives such as performance, reliability, weight, robustness, cost, and so on. To solve the conflicted requirements at the same time, multiobjective optimization is getting more popular in the design. Using the optimization, it becomes ordinary to get many solutions, such as Pareto solutions, quasi-Pareto solutions, and feasible solutions. The alternative solutions, however, are very difficult to be adopted to practical engineering decision directly. Therefore, to make the decision, proper information about the solutions in a function, parameter and real design space should be provided. In this paper, a new approach for the interpretation of Pareto solutions is proposed based on multidimensional visualization and clustering. The proposed method is applied to a thermal robustness and mass optimization problem of heat pipe shape design for an Artificial Satellite. The information gleaned from the propose approach can support the engineering decision for the design of Artificial Satellite heat pipe.
A P M Chiaradia - One of the best experts on this subject based on the ideXlab platform.
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onboard and real time Artificial Satellite orbit determination using gps
Mathematical Problems in Engineering, 2013Co-Authors: A P M Chiaradia, Helio Koiti Kuga, Antonio Fernando Bertachini De Almeida PradoAbstract:An algorithm for real-time and onboard orbit determination applying the Extended Kalman Filter (EKF) method is developed. Aiming at a very simple and still fairly accurate orbit determination, an analysis is performed to ascertain an adequacy of modeling complexity versus accuracy. The minimum set of to-be-estimated states to reach the level of accuracy of tens of meters is found to have at least the position, velocity, and user clock offset components. The dynamical model is assessed through several tests, covering force model, numerical integration scheme and step size, and simplified variational equations. The measurement model includes only relevant effects to the order of meters. The EKF method is chosen to be the simplest real-time estimation algorithm with adequate tuning of its parameters. In the developed procedure, the obtained position and velocity errors along a day vary from 15 to 20 m and from 0.014 to 0.018 m/s, respectively, with standard deviation from 6 to 10 m and from 0.006 to 0.008 m/s, respectively, with the SA either on or off. The results, as well as analysis of the final adopted models used, are presented in this work.
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single frequency gps measurements in real time Artificial Satellite orbit determination
Acta Astronautica, 2003Co-Authors: A P M Chiaradia, Helio Koiti Kuga, Antonio Fernando Bertachini De Almeida PradoAbstract:Abstract A simplified and compact algorithm with low computational cost providing an accuracy around tens of meters for Artificial Satellite orbit determination in real-time and on-board is developed in this work. The state estimation method is the extended Kalman filter. The Cowell's method is used to propagate the state vector, through a simple Runge–Kutta numerical integrator of fourth order with fixed step size. The modeled forces are due to the geopotential up to 50th order and degree of JGM-2 model. To time-update the state error covariance matrix, it is considered a simplified force model. In other words, in computing the state transition matrix, the effect of J2 (Earth flattening) is analytically considered, which unloads dramatically the processing time. In the measurement model, the single frequency GPS pseudorange is used, considering the effects of the ionospheric delay, clock offsets of the GPS and user Satellites, and relativistic effects. To validate this model, real live data are used from Topex/Poseidon Satellite and the results are compared with the Topex/Poseidon Precision Orbit Ephemeris (POE) generated by NASA/JPL, for several test cases. It is concluded that this compact algorithm enables accuracies of tens of meters with such simplified force model, analytical approach for computing the transition matrix, and a cheap GPS receiver providing single frequency pseudorange measurements.
