The grillage adaptive beam string structure(GABSS)is a new type of smart structure that can self-adjust its deformation and internal forces through a group of active struts(actuators)in response to changes in environm...The grillage adaptive beam string structure(GABSS)is a new type of smart structure that can self-adjust its deformation and internal forces through a group of active struts(actuators)in response to changes in environmental conditions.In this paper,an internal force control method based on a gradient–genetic algorithm(GGA)is proposed for the static control of a tensioned structure(especially the GABSS).Specifically,an optimization model of the GABSS is established in which the adjustment values of the actuators are set as the control variables,and the internal force of the beam is set as the objective function.The improved algorithm has the advantage of the global optimization ability of the genetic algorithm and the local search ability of the gradient algorithm.Two examples are provided to illustrate the application of the GGA method.The results show that the proposed method is practical for solving the internal force control problem of the GABSS.展开更多
In this paper, an experimental investigation on the flow structures in a turbulent bounda- ry layer employing a special laser light sheet-Hydrogen bubble flow visualization technique is described. It is observed that ...In this paper, an experimental investigation on the flow structures in a turbulent bounda- ry layer employing a special laser light sheet-Hydrogen bubble flow visualization technique is described. It is observed that the high/low speed streaks are directly related to the hairpin or horseshoe-like vortices. This observation can give a better understanding of the physical mechanism in the turbulent boundary layer.展开更多
This study proposes, from the theoretical point of view, the calculation of the gravitational constant <em>G</em>, made starting from the charge and the electron mass, taking the constant of the Fine Struc...This study proposes, from the theoretical point of view, the calculation of the gravitational constant <em>G</em>, made starting from the charge and the electron mass, taking the constant of the Fine Structure into examination. In the empty space, couples of virtual positron electrons dematerialize, giving virtual photon origin. They, at their time, will become electrons, positrons and so on. These transformations are made keeping the board of their “amount of movement” and when they meet the matter, these couples come, reissued depending on the field and on the matter mass. The matter is the change of the trend of their gyromagnetic movement relationship which puts under pressure. In presence of two masses, this gyromagnetic movement relationship is already partially oriented towards the other mass. From here a force is established between these two masses that give as calculated constant equal to 6.678532. This value of <em>G</em>, obtained leaving from the charge and the electron mass, is very near the experimental values estimated in these last decades regard the value of the gravitational constant of <em>G</em>.展开更多
基金supported by the National Key R&D Program of China(No.2017YFC0806100)the National Natural Science Foundation of China(No.51578491)。
文摘The grillage adaptive beam string structure(GABSS)is a new type of smart structure that can self-adjust its deformation and internal forces through a group of active struts(actuators)in response to changes in environmental conditions.In this paper,an internal force control method based on a gradient–genetic algorithm(GGA)is proposed for the static control of a tensioned structure(especially the GABSS).Specifically,an optimization model of the GABSS is established in which the adjustment values of the actuators are set as the control variables,and the internal force of the beam is set as the objective function.The improved algorithm has the advantage of the global optimization ability of the genetic algorithm and the local search ability of the gradient algorithm.Two examples are provided to illustrate the application of the GGA method.The results show that the proposed method is practical for solving the internal force control problem of the GABSS.
文摘In this paper, an experimental investigation on the flow structures in a turbulent bounda- ry layer employing a special laser light sheet-Hydrogen bubble flow visualization technique is described. It is observed that the high/low speed streaks are directly related to the hairpin or horseshoe-like vortices. This observation can give a better understanding of the physical mechanism in the turbulent boundary layer.
文摘This study proposes, from the theoretical point of view, the calculation of the gravitational constant <em>G</em>, made starting from the charge and the electron mass, taking the constant of the Fine Structure into examination. In the empty space, couples of virtual positron electrons dematerialize, giving virtual photon origin. They, at their time, will become electrons, positrons and so on. These transformations are made keeping the board of their “amount of movement” and when they meet the matter, these couples come, reissued depending on the field and on the matter mass. The matter is the change of the trend of their gyromagnetic movement relationship which puts under pressure. In presence of two masses, this gyromagnetic movement relationship is already partially oriented towards the other mass. From here a force is established between these two masses that give as calculated constant equal to 6.678532. This value of <em>G</em>, obtained leaving from the charge and the electron mass, is very near the experimental values estimated in these last decades regard the value of the gravitational constant of <em>G</em>.
