Fatty is one of the most important energy storage substances in the human body, and is an important source of energy in motion. It has 10 times bigger storage space than glycogen. Some studies suggest that in low to m...Fatty is one of the most important energy storage substances in the human body, and is an important source of energy in motion. It has 10 times bigger storage space than glycogen. Some studies suggest that in low to moderate intensity aerobic exercise, fat plays an important role providing energy. Especially when the movement lasts for more than 3 ~ 4h, energy provided by fat can account for 70% to 90% of total energy metabolism. Many people use many means and methods in order to increase the proportion of fat oxidation providing for energy in the movement and save glucose consumption in vivo, improving the body＇ s endurance. On the other hand, endurance exercise can burn fat properly, and play an important role to reduce accumulation of body fat, prevent hyperlipidemia and improve lipid levels.展开更多
This paper is dedicated to the study of viscous compressible barotropic fluids in dimension N ≥ 2. We address the question of well-posedness for large data having critical Besov regularity. Our result improves N the...This paper is dedicated to the study of viscous compressible barotropic fluids in dimension N ≥ 2. We address the question of well-posedness for large data having critical Besov regularity. Our result improves N the analysis of Danchin and of the author inasmuch as we may take initial density in BN/p p,1 with 1 ≤ p 〈 ＋∞. Our result relies on a new a priori estimate for the velocity, where we introduce a new unknown called effective velocity to weaken one of the couplings between the density and the velocity. In particular, our result is the first in which we obtain uniqueness without imposing hypothesis on the gradient of the density.展开更多
Normally large amounts of particles are required to accurately simulate the metal cutting process,which consumes a lot of computing time and storage.Adaptive techniques can help decrease the number of particles,hence ...Normally large amounts of particles are required to accurately simulate the metal cutting process,which consumes a lot of computing time and storage.Adaptive techniques can help decrease the number of particles,hence reducing the runtime.This paper presents a novel adaptive smoothed particle hydrodynamics(SPH)method for the metal cutting simulation.The spatial resolution changes adaptively according to the distance to the tool tip by the particle splitting and merging.More particles are selected in the region where the workpiece and the tool are in contact.Since the contact region constantly changes during the cutting process,two quadrilateral frames are adopted in the adaptive algorithm to dynamically change the distribution of particles.One frame for the refinement,the other for the coarsening.These frames move at the same speed as the tool.To test the computational efficiency,the metal cutting process is simulated by using SPH with three different adaptive approaches.Numerical results show that the proposed adaptive algorithm with dynamic refinement and coarsening can significantly optimize the runtime.展开更多
文摘Fatty is one of the most important energy storage substances in the human body, and is an important source of energy in motion. It has 10 times bigger storage space than glycogen. Some studies suggest that in low to moderate intensity aerobic exercise, fat plays an important role providing energy. Especially when the movement lasts for more than 3 ~ 4h, energy provided by fat can account for 70% to 90% of total energy metabolism. Many people use many means and methods in order to increase the proportion of fat oxidation providing for energy in the movement and save glucose consumption in vivo, improving the body＇ s endurance. On the other hand, endurance exercise can burn fat properly, and play an important role to reduce accumulation of body fat, prevent hyperlipidemia and improve lipid levels.
文摘This paper is dedicated to the study of viscous compressible barotropic fluids in dimension N ≥ 2. We address the question of well-posedness for large data having critical Besov regularity. Our result improves N the analysis of Danchin and of the author inasmuch as we may take initial density in BN/p p,1 with 1 ≤ p 〈 ＋∞. Our result relies on a new a priori estimate for the velocity, where we introduce a new unknown called effective velocity to weaken one of the couplings between the density and the velocity. In particular, our result is the first in which we obtain uniqueness without imposing hypothesis on the gradient of the density.
基金the National Natural Science Foundation of China(Grant Nos.12002290 and 11772274).
文摘Normally large amounts of particles are required to accurately simulate the metal cutting process,which consumes a lot of computing time and storage.Adaptive techniques can help decrease the number of particles,hence reducing the runtime.This paper presents a novel adaptive smoothed particle hydrodynamics(SPH)method for the metal cutting simulation.The spatial resolution changes adaptively according to the distance to the tool tip by the particle splitting and merging.More particles are selected in the region where the workpiece and the tool are in contact.Since the contact region constantly changes during the cutting process,two quadrilateral frames are adopted in the adaptive algorithm to dynamically change the distribution of particles.One frame for the refinement,the other for the coarsening.These frames move at the same speed as the tool.To test the computational efficiency,the metal cutting process is simulated by using SPH with three different adaptive approaches.Numerical results show that the proposed adaptive algorithm with dynamic refinement and coarsening can significantly optimize the runtime.
