The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Kutluy ı L Doğançay - One of the best experts on this subject based on the ideXlab platform.
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Algebraic Solution for stationary emitter geolocation by a LEO satellite using Doppler frequency measurements
2016 IEEE International Conference on Acoustics Speech and Signal Processing (ICASSP), 2016Co-Authors: Ngoc Hung Nguyen, Kutluy ı L DoğançayAbstract:This paper presents a new Algebraic Solution for the Doppler positioning problem where the position of a stationary emitter is estimated from Doppler frequency measurements collected by a single low-earth-orbit (LEO) satellite. The proposed Algebraic Solution can be used for effective initialization of more sophisticated iterative algorithms as it produces estimates sufficiently close to the actual position of the emitter to ensure convergence. It is computationally more efficient than existing initialization techniques, based on the point of closest approach, which require expensive nonlinear curve fitting procedures. The effectiveness of the proposed Algebraic Solution is demonstrated by way of numerical simulations.
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ICASSP - Algebraic Solution for stationary emitter geolocation by a LEO satellite using Doppler frequency measurements
2016 IEEE International Conference on Acoustics Speech and Signal Processing (ICASSP), 2016Co-Authors: Ngoc Hung Nguyen, Kutluy ı L DoğançayAbstract:This paper presents a new Algebraic Solution for the Doppler positioning problem where the position of a stationary emitter is estimated from Doppler frequency measurements collected by a single low-earth-orbit (LEO) satellite. The proposed Algebraic Solution can be used for effective initialization of more sophisticated iterative algorithms as it produces estimates sufficiently close to the actual position of the emitter to ensure convergence. It is computationally more efficient than existing initialization techniques, based on the point of closest approach, which require expensive nonlinear curve fitting procedures. The effectiveness of the proposed Algebraic Solution is demonstrated by way of numerical simulations.
Fernando T. Knabben - One of the best experts on this subject based on the ideXlab platform.
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Algebraic Solution of capillary tube flows part ii capillary tube suction line heat exchangers
Applied Thermal Engineering, 2010Co-Authors: Christian J.l. Hermes, Cláudio Melo, Fernando T. KnabbenAbstract:Capillary tube suction line heat exchangers have been modeled using both numerical and analytical approaches. The former requires a reasonable understanding of the governing heat and fluid flow equations, thermodynamic relations, numerical methods, and computer programming, and therefore are not suitable for most refrigeration and air-conditioning practitioners. Alternatively, empirical Algebraic formulations for diabatic capillary tube flows have been proposed in the literature, in spite of their lack of generality and accuracy. This paper introduces a physically consistent, unconditionally convergent, easy-to-implement semi-empirical Algebraic model for capillary tube suction line heat exchangers, with the same level of accuracy as found with more sophisticated first-principles models. The methodology treats the refrigerant flow and the heat transfer as independent phenomena, thus allowing the derivation of explicit Algebraic expressions for the refrigerant mass flow rate and the heat exchanger effectiveness. The thermal and hydraulic models are then conflated through the so-called Buckingham-π theorem using in-house experimental data collected for diabatic capillary tube flows of refrigerants HFC-134a and HC-600a. Comparisons between the model predictions and the experimental data revealed that more than 90% and nearly 100% of all data can be predicted within ±10% and ±15% error bands, respectively.
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Algebraic Solution of capillary tube flows: Part I: Adiabatic capillary tubes
Applied Thermal Engineering, 2010Co-Authors: Christian J.l. Hermes, Cláudio Melo, Fernando T. KnabbenAbstract:Capillary tube flows have been solved through both numerical and analytical approaches. The former requires a reasonable understanding of the governing equations of heat and fluid flow, thermodynamic relations, numerical methods, and computer programming, and therefore are not the suitable approach for most refrigeration and air-conditioning practitioners. Some simpler procedures based on different strategies for analytically solving the capillary tube flow have been proposed in the literature, although iterative loops for calculating the mass flow rate are still required. The aim of this work is to advance a semi-empirical Algebraic model to solve adiabatic capillary tube flows using a relatively simple set of thermodynamic relations and being explicit for the mass flow rate calculation. Comparisons with a comprehensive experimental data set, taken with the refrigerants HFC-134a and HC-600a, has shown that the model predicts more than 90% and nearly 100% of all data within ±10% and ±15% error bands, respectively.
Ngoc Hung Nguyen - One of the best experts on this subject based on the ideXlab platform.
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Algebraic Solution for stationary emitter geolocation by a LEO satellite using Doppler frequency measurements
2016 IEEE International Conference on Acoustics Speech and Signal Processing (ICASSP), 2016Co-Authors: Ngoc Hung Nguyen, Kutluy ı L DoğançayAbstract:This paper presents a new Algebraic Solution for the Doppler positioning problem where the position of a stationary emitter is estimated from Doppler frequency measurements collected by a single low-earth-orbit (LEO) satellite. The proposed Algebraic Solution can be used for effective initialization of more sophisticated iterative algorithms as it produces estimates sufficiently close to the actual position of the emitter to ensure convergence. It is computationally more efficient than existing initialization techniques, based on the point of closest approach, which require expensive nonlinear curve fitting procedures. The effectiveness of the proposed Algebraic Solution is demonstrated by way of numerical simulations.
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ICASSP - Algebraic Solution for stationary emitter geolocation by a LEO satellite using Doppler frequency measurements
2016 IEEE International Conference on Acoustics Speech and Signal Processing (ICASSP), 2016Co-Authors: Ngoc Hung Nguyen, Kutluy ı L DoğançayAbstract:This paper presents a new Algebraic Solution for the Doppler positioning problem where the position of a stationary emitter is estimated from Doppler frequency measurements collected by a single low-earth-orbit (LEO) satellite. The proposed Algebraic Solution can be used for effective initialization of more sophisticated iterative algorithms as it produces estimates sufficiently close to the actual position of the emitter to ensure convergence. It is computationally more efficient than existing initialization techniques, based on the point of closest approach, which require expensive nonlinear curve fitting procedures. The effectiveness of the proposed Algebraic Solution is demonstrated by way of numerical simulations.
Christian J.l. Hermes - One of the best experts on this subject based on the ideXlab platform.
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Algebraic Solution of capillary tube flows part ii capillary tube suction line heat exchangers
Applied Thermal Engineering, 2010Co-Authors: Christian J.l. Hermes, Cláudio Melo, Fernando T. KnabbenAbstract:Capillary tube suction line heat exchangers have been modeled using both numerical and analytical approaches. The former requires a reasonable understanding of the governing heat and fluid flow equations, thermodynamic relations, numerical methods, and computer programming, and therefore are not suitable for most refrigeration and air-conditioning practitioners. Alternatively, empirical Algebraic formulations for diabatic capillary tube flows have been proposed in the literature, in spite of their lack of generality and accuracy. This paper introduces a physically consistent, unconditionally convergent, easy-to-implement semi-empirical Algebraic model for capillary tube suction line heat exchangers, with the same level of accuracy as found with more sophisticated first-principles models. The methodology treats the refrigerant flow and the heat transfer as independent phenomena, thus allowing the derivation of explicit Algebraic expressions for the refrigerant mass flow rate and the heat exchanger effectiveness. The thermal and hydraulic models are then conflated through the so-called Buckingham-π theorem using in-house experimental data collected for diabatic capillary tube flows of refrigerants HFC-134a and HC-600a. Comparisons between the model predictions and the experimental data revealed that more than 90% and nearly 100% of all data can be predicted within ±10% and ±15% error bands, respectively.
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Algebraic Solution of capillary tube flows: Part I: Adiabatic capillary tubes
Applied Thermal Engineering, 2010Co-Authors: Christian J.l. Hermes, Cláudio Melo, Fernando T. KnabbenAbstract:Capillary tube flows have been solved through both numerical and analytical approaches. The former requires a reasonable understanding of the governing equations of heat and fluid flow, thermodynamic relations, numerical methods, and computer programming, and therefore are not the suitable approach for most refrigeration and air-conditioning practitioners. Some simpler procedures based on different strategies for analytically solving the capillary tube flow have been proposed in the literature, although iterative loops for calculating the mass flow rate are still required. The aim of this work is to advance a semi-empirical Algebraic model to solve adiabatic capillary tube flows using a relatively simple set of thermodynamic relations and being explicit for the mass flow rate calculation. Comparisons with a comprehensive experimental data set, taken with the refrigerants HFC-134a and HC-600a, has shown that the model predicts more than 90% and nearly 100% of all data within ±10% and ±15% error bands, respectively.
Tommaso Isernia - One of the best experts on this subject based on the ideXlab platform.
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an Algebraic Solution method for nonlinear inverse scattering
IEEE Transactions on Antennas and Propagation, 2015Co-Authors: Martina T Bevacqua, Lorenzo Crocco, Loreto Di Donato, Tommaso IserniaAbstract:By using properly designed synthetic (or “virtual”) experiments and an original approximation of the contrast sources, we are able to recast the inverse scattering problem in an Algebraic form (in a subset of points of the imaged domain) and, hence, to solve it by means of closed form formulas. The new approximation relies on the assumption that the contrast sources induced by the different virtual experiments are focused in given points belonging to the scatterer. As such, the method involves a preprocessing step in which the outcome of the original scattering experiments is recombined into the new, virtual, ones capable of enforcing the expected contrast sources behavior. Examples with numerical and experimental data are provided to assess the actual possibility of setting such a virtual experiments framework, and show the effectiveness of the proposed method.
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an Algebraic Solution method for nonlinear inverse scattering
IEEE Transactions on Antennas and Propagation, 2015Co-Authors: Martina T Bevacqua, Lorenzo Crocco, Loreto Di Donato, Tommaso IserniaAbstract:By using properly designed synthetic (or “virtual”) experiments and an original approximation of the contrast sources, we are able to recast the inverse scattering problem in an Algebraic form (in a subset of points of the imaged domain) and, hence, to solve it by means of closed form formulas. The new approximation relies on the assumption that the contrast sources induced by the different virtual experiments are focused in given points belonging to the scatterer. As such, the method involves a preprocessing step in which the outcome of the original scattering experiments is recombined into the new, virtual, ones capable of enforcing the expected contrast sources behavior. Examples with numerical and experimental data are provided to assess the actual possibility of setting such a virtual experiments framework, and show the effectiveness of the proposed method.
