In this paper,for the solution of the torsion problem about the equation Δu=-2 with homogeneous Dirichlet boundary conditions in a bounded convex domain in Rn,we find a superharmonic function which implies the strict...In this paper,for the solution of the torsion problem about the equation Δu=-2 with homogeneous Dirichlet boundary conditions in a bounded convex domain in Rn,we find a superharmonic function which implies the strict concavity of u ^(1/2) and give some convexity estimates.It is a generalization of Makar-Limanov’s result(Makar-Limanov(1971))and Ma-Shi-Ye’s result(Ma et al.(2012)).展开更多
The solution of dynamic Point-Ring-Couple at the origin, on z=0 plane, in an elastic space is presented and its properties are discussed. Let shocking loads be uniformly distributed, along the direction of circumferen...The solution of dynamic Point-Ring-Couple at the origin, on z=0 plane, in an elastic space is presented and its properties are discussed. Let shocking loads be uniformly distributed, along the direction of circumference, at a circle, on z=0 plane, with radius a and centered at the origin. Then, the solution of our problem is obtained via integral calculation for a 0. When the intensity of this dynamic Point-Ring-Couple is varied with sincot, the cones in the elastic space with apex at the origin and the z-axis be its symmetric axis, become zero stressed surfaces at any time instance. The solution of dynamic torsion problem of revolution solids with these cones as boundary under the application of torque varied with sincot is found.展开更多
基金supported by National Key Research and Development Project (Grant No. SQ2020YFA070080)National Natural Science Foundation of China (Grant Nos. 11871255 and 11721101)supported by National Natural Science Foundation of China (Grant Nos. 11971137 and 11771396)
文摘In this paper,for the solution of the torsion problem about the equation Δu=-2 with homogeneous Dirichlet boundary conditions in a bounded convex domain in Rn,we find a superharmonic function which implies the strict concavity of u ^(1/2) and give some convexity estimates.It is a generalization of Makar-Limanov’s result(Makar-Limanov(1971))and Ma-Shi-Ye’s result(Ma et al.(2012)).
基金Project supported by Natural Science Foundation of Guangdong Province
文摘The solution of dynamic Point-Ring-Couple at the origin, on z=0 plane, in an elastic space is presented and its properties are discussed. Let shocking loads be uniformly distributed, along the direction of circumference, at a circle, on z=0 plane, with radius a and centered at the origin. Then, the solution of our problem is obtained via integral calculation for a 0. When the intensity of this dynamic Point-Ring-Couple is varied with sincot, the cones in the elastic space with apex at the origin and the z-axis be its symmetric axis, become zero stressed surfaces at any time instance. The solution of dynamic torsion problem of revolution solids with these cones as boundary under the application of torque varied with sincot is found.