Analyzed roof rock layer structure and rock layer thickness of -550 level west main roadway and proposed that the stability of calcareous rock layer was the premise of mining successfully. According to different roof ...Analyzed roof rock layer structure and rock layer thickness of -550 level west main roadway and proposed that the stability of calcareous rock layer was the premise of mining successfully. According to different roof condition and rock pillar size of main roadway, different reinforcement plans were used to strengthen the stability of rock layer. By studying the influence rule and influence scope of dynamic pressure of main roadway wall rock because of fully mechanized coal face extracting, that the size of rock pillar was the key of affecting wall rock distorting was proposed. Scientific basis was provided for determining the size of reasonable rock pillar, selecting reasonable extracting support plan and reinforcement measures under different wall rock conditions.展开更多
In this paper we are concerned with the regularity of solutions to the Navier-Stokes equations with the condition on the pressure on parts of the boundary where there is flow. For the steady Stokes problem a result si...In this paper we are concerned with the regularity of solutions to the Navier-Stokes equations with the condition on the pressure on parts of the boundary where there is flow. For the steady Stokes problem a result similar to L q-theory for the one with Dirichlet boundary condition is obtained. Using the result, for the steady Navier-Stokes equations we obtain regularity as the case of Dirichlet boundary conditions. Furthermore,for the time-dependent 2-D Navier-Stokes equations we prove uniqueness and existence of regular solutions,which is similar to J.M.Bernard's results[6]for the time-dependent 2-D Stokes equations.展开更多
文摘Analyzed roof rock layer structure and rock layer thickness of -550 level west main roadway and proposed that the stability of calcareous rock layer was the premise of mining successfully. According to different roof condition and rock pillar size of main roadway, different reinforcement plans were used to strengthen the stability of rock layer. By studying the influence rule and influence scope of dynamic pressure of main roadway wall rock because of fully mechanized coal face extracting, that the size of rock pillar was the key of affecting wall rock distorting was proposed. Scientific basis was provided for determining the size of reasonable rock pillar, selecting reasonable extracting support plan and reinforcement measures under different wall rock conditions.
基金Supported by TWAS,UNESCO and AMSS in Chinese Academy of Sciences
文摘In this paper we are concerned with the regularity of solutions to the Navier-Stokes equations with the condition on the pressure on parts of the boundary where there is flow. For the steady Stokes problem a result similar to L q-theory for the one with Dirichlet boundary condition is obtained. Using the result, for the steady Navier-Stokes equations we obtain regularity as the case of Dirichlet boundary conditions. Furthermore,for the time-dependent 2-D Navier-Stokes equations we prove uniqueness and existence of regular solutions,which is similar to J.M.Bernard's results[6]for the time-dependent 2-D Stokes equations.