This paper discusses the global existence and quenching of the solution to the Newton filtration equation with the nonlinear boundary condition. The authors also discuss the profile of the quenching solution in the qu...This paper discusses the global existence and quenching of the solution to the Newton filtration equation with the nonlinear boundary condition. The authors also discuss the profile of the quenching solution in the quenching time and obtain the quenching rate of the quenching solution.展开更多
Known as laser trapping,optical tweezers,with nanometer accuracy and pico-newton precision,plays a pivotal role in single bio-molecule measurements and controllable motions of micro-machines.In order to advance the fl...Known as laser trapping,optical tweezers,with nanometer accuracy and pico-newton precision,plays a pivotal role in single bio-molecule measurements and controllable motions of micro-machines.In order to advance the flourishing applications for those achievements,it is necessary to make clear the three-dimensional dynamic process of micro-particles stepping into an optical field.In this paper,we utilize the ray optics method to calculate the optical force and optical torque of a micro-sphere in optical tweezers.With the influence of viscosity force and torque taken into account,we numerically solve and analyze the dynamic process of a dielectric micro-sphere in optical tweezers on the basis of Newton mechanical equations under various conditions of initial positions and velocity vectors of the particle.The particle trajectory over time can demonstrate whether the particle can be successfully trapped into the optical tweezers center and reveal the subtle details of this trapping process.Even in a simple pair of optical tweezers,the dielectric micro-sphere exhibits abundant phases of mechanical motions including acceleration,deceleration,and turning.These studies will be of great help to understand the particle-laser trap interaction in various situations and promote exciting possibilities for exploring novel ways to control the mechanical dynamics of microscale particles.展开更多
This paper presents a new nine⁃degree⁃of⁃freedom parallel mechanism,which can be applied as a flight simulator.The mechanism is composed by Stewart turntable and another three⁃axis turntable.The Stewart platform can r...This paper presents a new nine⁃degree⁃of⁃freedom parallel mechanism,which can be applied as a flight simulator.The mechanism is composed by Stewart turntable and another three⁃axis turntable.The Stewart platform can realize six⁃degree⁃of⁃freedom movement in space,but the working space is limited.After the three⁃axis turntable is installed,the rotation space can be increased to simulate more realistic flight conditions.This paper analyzes the new flight simulator from kinematics and dynamics aspects.In addition,the flight simulator is simulated and analyzed based on the MATLAB/Simulink simulation system.The results obtained from the numerical simulations is planned to be used for the practical manufacturing and applications of the new platform.展开更多
This paper presents the method of solving the equations of motions by evolutionary algorithms. Starting from random trajectory, the solution is obtained by accepting the mutation if it leads to a better...This paper presents the method of solving the equations of motions by evolutionary algorithms. Starting from random trajectory, the solution is obtained by accepting the mutation if it leads to a better approximations of Newton’s second law. The general method is illustrated by finding trajectory to the Moon.展开更多
文摘This paper discusses the global existence and quenching of the solution to the Newton filtration equation with the nonlinear boundary condition. The authors also discuss the profile of the quenching solution in the quenching time and obtain the quenching rate of the quenching solution.
基金This work is supported by the National Natural Science Foundation of China(Grant No.11974119 and No.11804399)the Guangdong Innovative and Entrepreneurial Research Team Program(Grant No.2016ZT06C594)+1 种基金the Fundamental Research Funds for the Central Universities,South-Central University for Nationalities(Grant No.CZQ20018)National Key R&D Program of China(No.2018YFA 0306200).
文摘Known as laser trapping,optical tweezers,with nanometer accuracy and pico-newton precision,plays a pivotal role in single bio-molecule measurements and controllable motions of micro-machines.In order to advance the flourishing applications for those achievements,it is necessary to make clear the three-dimensional dynamic process of micro-particles stepping into an optical field.In this paper,we utilize the ray optics method to calculate the optical force and optical torque of a micro-sphere in optical tweezers.With the influence of viscosity force and torque taken into account,we numerically solve and analyze the dynamic process of a dielectric micro-sphere in optical tweezers on the basis of Newton mechanical equations under various conditions of initial positions and velocity vectors of the particle.The particle trajectory over time can demonstrate whether the particle can be successfully trapped into the optical tweezers center and reveal the subtle details of this trapping process.Even in a simple pair of optical tweezers,the dielectric micro-sphere exhibits abundant phases of mechanical motions including acceleration,deceleration,and turning.These studies will be of great help to understand the particle-laser trap interaction in various situations and promote exciting possibilities for exploring novel ways to control the mechanical dynamics of microscale particles.
文摘This paper presents a new nine⁃degree⁃of⁃freedom parallel mechanism,which can be applied as a flight simulator.The mechanism is composed by Stewart turntable and another three⁃axis turntable.The Stewart platform can realize six⁃degree⁃of⁃freedom movement in space,but the working space is limited.After the three⁃axis turntable is installed,the rotation space can be increased to simulate more realistic flight conditions.This paper analyzes the new flight simulator from kinematics and dynamics aspects.In addition,the flight simulator is simulated and analyzed based on the MATLAB/Simulink simulation system.The results obtained from the numerical simulations is planned to be used for the practical manufacturing and applications of the new platform.
文摘This paper presents the method of solving the equations of motions by evolutionary algorithms. Starting from random trajectory, the solution is obtained by accepting the mutation if it leads to a better approximations of Newton’s second law. The general method is illustrated by finding trajectory to the Moon.