The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Anne De Wit - One of the best experts on this subject based on the ideXlab platform.
-
a b c reaction fronts in hele shaw cells under modulated Gravitational Acceleration
Physical Chemistry Chemical Physics, 2012Co-Authors: Kerstin Eckert, Laurence Rongy, Anne De WitAbstract:The dynamics of A + B → C reaction fronts is studied under modulated Gravitational Acceleration by means of a combination of parabolic flight experiments and numerical simulations. During modulated gravity the front position undergoes periodic modulation with an accelerated front propagation under hyper-gravity together with a slowing down under low gravity. The underlying reason for this is an amplification and a decay, respectively, of the buoyancy-driven double vortex associated with the front propagation under standard Gravitational Acceleration, as explained by reaction–diffusion–convection simulations of convection around an A + B → C front. Deeper insights into the correlation between grey-value changes in the experimental shadowgraph images and characteristic changes in the concentration profiles are obtained by a numerical simulation of the imaging process.
-
A + B → C reaction fronts in Hele-Shaw cells under modulated Gravitational Acceleration.
Physical chemistry chemical physics : PCCP, 2012Co-Authors: Kerstin Eckert, Laurence Rongy, Anne De WitAbstract:The dynamics of A + B → C reaction fronts is studied under modulated Gravitational Acceleration by means of a combination of parabolic flight experiments and numerical simulations. During modulated gravity the front position undergoes periodic modulation with an accelerated front propagation under hyper-gravity together with a slowing down under low gravity. The underlying reason for this is an amplification and a decay, respectively, of the buoyancy-driven double vortex associated with the front propagation under standard Gravitational Acceleration, as explained by reaction–diffusion–convection simulations of convection around an A + B → C front. Deeper insights into the correlation between grey-value changes in the experimental shadowgraph images and characteristic changes in the concentration profiles are obtained by a numerical simulation of the imaging process.
Yan Wang - One of the best experts on this subject based on the ideXlab platform.
-
a novel Gravitational Acceleration enhanced particle swarm optimization algorithm for wind thermal economic emission dispatch problem considering wind power availability
International Journal of Electrical Power & Energy Systems, 2015Co-Authors: Shanhe Jiang, Yan WangAbstract:Abstract To reduce the pollutant atmospheric emission level, a Wind–thermal Economic Emission Dispatch (WTEED) model considering the coordination of power allocation from thermal and wind power generators is established. Among the model formulation, the fuel cost and emission level of thermal units and the operating cost caused by wind power availability are comprehensively investigated here. Also, the cost of wind energy including overestimation and underestimation of available wind power using Weibull-based probability density function is also given in a closed-form expression according to the incomplete gamma function to characterize the impact of wind power. To seek the optimum fuel cost, optimum emission level and best compromise solution, a newly developed optimization approach, known as Gravitational Acceleration enhanced particle swarm optimization algorithm (GAEPSO), has been adopted to solve the model in this work. The approach adopts co-evolutionary technique to simultaneously update particles velocity with PSO velocity and GSA Acceleration and fully incorporates the ability of exploration in PSO and the ability of exploitation in GSA. GAEPSO, therefore, is expected to obtain an efficient balance between exploration and exploitation. The potential of the proposed algorithm is assessed in terms of the minimum fuel cost, minimum emission and best compromise solution obtained for conventional thermal generators and modified wind–thermal generators test systems. The results obtained validate the feasibility and effectiveness of the proposed algorithm compared to PSO, GSA and other recently developed approaches. Both the Pareto-optimal set and the convergence speed of the proposed algorithm are also found to be better than, or at least comparable to other algorithms.
-
A novel Gravitational Acceleration enhanced particle swarm optimization algorithm for wind–thermal economic emission dispatch problem considering wind power availability
International Journal of Electrical Power & Energy Systems, 2015Co-Authors: Shanhe Jiang, Yan WangAbstract:Abstract To reduce the pollutant atmospheric emission level, a Wind–thermal Economic Emission Dispatch (WTEED) model considering the coordination of power allocation from thermal and wind power generators is established. Among the model formulation, the fuel cost and emission level of thermal units and the operating cost caused by wind power availability are comprehensively investigated here. Also, the cost of wind energy including overestimation and underestimation of available wind power using Weibull-based probability density function is also given in a closed-form expression according to the incomplete gamma function to characterize the impact of wind power. To seek the optimum fuel cost, optimum emission level and best compromise solution, a newly developed optimization approach, known as Gravitational Acceleration enhanced particle swarm optimization algorithm (GAEPSO), has been adopted to solve the model in this work. The approach adopts co-evolutionary technique to simultaneously update particles velocity with PSO velocity and GSA Acceleration and fully incorporates the ability of exploration in PSO and the ability of exploitation in GSA. GAEPSO, therefore, is expected to obtain an efficient balance between exploration and exploitation. The potential of the proposed algorithm is assessed in terms of the minimum fuel cost, minimum emission and best compromise solution obtained for conventional thermal generators and modified wind–thermal generators test systems. The results obtained validate the feasibility and effectiveness of the proposed algorithm compared to PSO, GSA and other recently developed approaches. Both the Pareto-optimal set and the convergence speed of the proposed algorithm are also found to be better than, or at least comparable to other algorithms.
Kerstin Eckert - One of the best experts on this subject based on the ideXlab platform.
-
a b c reaction fronts in hele shaw cells under modulated Gravitational Acceleration
Physical Chemistry Chemical Physics, 2012Co-Authors: Kerstin Eckert, Laurence Rongy, Anne De WitAbstract:The dynamics of A + B → C reaction fronts is studied under modulated Gravitational Acceleration by means of a combination of parabolic flight experiments and numerical simulations. During modulated gravity the front position undergoes periodic modulation with an accelerated front propagation under hyper-gravity together with a slowing down under low gravity. The underlying reason for this is an amplification and a decay, respectively, of the buoyancy-driven double vortex associated with the front propagation under standard Gravitational Acceleration, as explained by reaction–diffusion–convection simulations of convection around an A + B → C front. Deeper insights into the correlation between grey-value changes in the experimental shadowgraph images and characteristic changes in the concentration profiles are obtained by a numerical simulation of the imaging process.
-
A + B → C reaction fronts in Hele-Shaw cells under modulated Gravitational Acceleration.
Physical chemistry chemical physics : PCCP, 2012Co-Authors: Kerstin Eckert, Laurence Rongy, Anne De WitAbstract:The dynamics of A + B → C reaction fronts is studied under modulated Gravitational Acceleration by means of a combination of parabolic flight experiments and numerical simulations. During modulated gravity the front position undergoes periodic modulation with an accelerated front propagation under hyper-gravity together with a slowing down under low gravity. The underlying reason for this is an amplification and a decay, respectively, of the buoyancy-driven double vortex associated with the front propagation under standard Gravitational Acceleration, as explained by reaction–diffusion–convection simulations of convection around an A + B → C front. Deeper insights into the correlation between grey-value changes in the experimental shadowgraph images and characteristic changes in the concentration profiles are obtained by a numerical simulation of the imaging process.
Guido Ferretti - One of the best experts on this subject based on the ideXlab platform.
-
Effects of Gravitational Acceleration on cardiovascular autonomic control in resting humans
European Journal of Applied Physiology, 2015Co-Authors: Timothée Fontolliet, Guglielmo Antonutto, Julien Bonjour, Jean-claude Barthelemy, Vincent Pichot, Carlo Capelli, Guido FerrettiAbstract:Purpose Previous studies of cardiovascular responses in hypergravity suggest increased sympathetic regulation. The analysis of spontaneous heart rate variability (HRV) parameters and spontaneous baroreflex sensitivity (BRS) informs on the reciprocal balance of parasympathetic and sympathetic regulations at rest. This paper was aimed at determining the effects of Gravitational Acceleration ( a _g) on HRV and BRS. Methods Eleven healthy subjects (age 26.6 ± 6.1) were studied in a human centrifuge at four a _g levels (1, 1.5, 2 and 2.5 g) during 5-min sessions at rest. We evaluated spontaneous variability of R–R interval (RR), and of systolic and diastolic blood pressure (SAP and DAP, respectively), by power spectral analysis, and BRS by the sequence method, using the BRSanalysis^® software. Results At 2.5 g, compared to 1 g, (1) the total power ( P _TOT) and the powers of LF and HF components of HRV were lower, while the LF/HF ratio was higher; (2) normalized units for LF and HF did not changed significantly; (3) the P _TOT, LF and HF powers of SAP were higher; (4) the P _TOT and LF power of DAP were higher; and (5) BRS was decreased. Conclusions These results do not agree with the notion of sympathetic up-regulation supported by the increase in HR and DAP (tonic indices), and of SAP and DAP LF powers (oscillatory indices). The P _TOT reduction leads to speculate that only the sympathetic branch of the ANS might have been active during elevated a _g exposure. The vascular response occurred in a condition of massive baroreceptive unloading.
-
Effects of Gravitational Acceleration on cardiovascular autonomic control in resting humans
European journal of applied physiology, 2015Co-Authors: Timothée Fontolliet, Guglielmo Antonutto, Julien Bonjour, Jean-claude Barthelemy, Vincent Pichot, Carlo Capelli, Enrico Tam, Guido FerrettiAbstract:Purpose Previous studies of cardiovascular responses in hypergravity suggest increased sympathetic regulation. The analysis of spontaneous heart rate variability (HRV) parameters and spontaneous baroreflex sensitivity (BRS) informs on the reciprocal balance of parasympathetic and sympathetic regulations at rest. This paper was aimed at determining the effects of Gravitational Acceleration (a g) on HRV and BRS.
Shanhe Jiang - One of the best experts on this subject based on the ideXlab platform.
-
a novel Gravitational Acceleration enhanced particle swarm optimization algorithm for wind thermal economic emission dispatch problem considering wind power availability
International Journal of Electrical Power & Energy Systems, 2015Co-Authors: Shanhe Jiang, Yan WangAbstract:Abstract To reduce the pollutant atmospheric emission level, a Wind–thermal Economic Emission Dispatch (WTEED) model considering the coordination of power allocation from thermal and wind power generators is established. Among the model formulation, the fuel cost and emission level of thermal units and the operating cost caused by wind power availability are comprehensively investigated here. Also, the cost of wind energy including overestimation and underestimation of available wind power using Weibull-based probability density function is also given in a closed-form expression according to the incomplete gamma function to characterize the impact of wind power. To seek the optimum fuel cost, optimum emission level and best compromise solution, a newly developed optimization approach, known as Gravitational Acceleration enhanced particle swarm optimization algorithm (GAEPSO), has been adopted to solve the model in this work. The approach adopts co-evolutionary technique to simultaneously update particles velocity with PSO velocity and GSA Acceleration and fully incorporates the ability of exploration in PSO and the ability of exploitation in GSA. GAEPSO, therefore, is expected to obtain an efficient balance between exploration and exploitation. The potential of the proposed algorithm is assessed in terms of the minimum fuel cost, minimum emission and best compromise solution obtained for conventional thermal generators and modified wind–thermal generators test systems. The results obtained validate the feasibility and effectiveness of the proposed algorithm compared to PSO, GSA and other recently developed approaches. Both the Pareto-optimal set and the convergence speed of the proposed algorithm are also found to be better than, or at least comparable to other algorithms.
-
A novel Gravitational Acceleration enhanced particle swarm optimization algorithm for wind–thermal economic emission dispatch problem considering wind power availability
International Journal of Electrical Power & Energy Systems, 2015Co-Authors: Shanhe Jiang, Yan WangAbstract:Abstract To reduce the pollutant atmospheric emission level, a Wind–thermal Economic Emission Dispatch (WTEED) model considering the coordination of power allocation from thermal and wind power generators is established. Among the model formulation, the fuel cost and emission level of thermal units and the operating cost caused by wind power availability are comprehensively investigated here. Also, the cost of wind energy including overestimation and underestimation of available wind power using Weibull-based probability density function is also given in a closed-form expression according to the incomplete gamma function to characterize the impact of wind power. To seek the optimum fuel cost, optimum emission level and best compromise solution, a newly developed optimization approach, known as Gravitational Acceleration enhanced particle swarm optimization algorithm (GAEPSO), has been adopted to solve the model in this work. The approach adopts co-evolutionary technique to simultaneously update particles velocity with PSO velocity and GSA Acceleration and fully incorporates the ability of exploration in PSO and the ability of exploitation in GSA. GAEPSO, therefore, is expected to obtain an efficient balance between exploration and exploitation. The potential of the proposed algorithm is assessed in terms of the minimum fuel cost, minimum emission and best compromise solution obtained for conventional thermal generators and modified wind–thermal generators test systems. The results obtained validate the feasibility and effectiveness of the proposed algorithm compared to PSO, GSA and other recently developed approaches. Both the Pareto-optimal set and the convergence speed of the proposed algorithm are also found to be better than, or at least comparable to other algorithms.
