The displacements and geometry of the rock blocks and the properties of the rock struc-ture play an important role in the stability of tunnels.Based on the key block model,the dynamic instability analysis of undergrou...The displacements and geometry of the rock blocks and the properties of the rock struc-ture play an important role in the stability of tunnels.Based on the key block model,the dynamic instability analysis of underground tunnel subjected to intensive short-time compressional wave was conducted.The instability of the tunnel caused by the spallation and the inertial effect was distin-guished.And the influence of the roof contour curvature of tunnel was also determined.展开更多
In this paper,we present a surface reconstruction via 2D strokes and a vector field on the strokes based on a two-step method.In the first step,from sparse strokes drawn by artists and a given vector field on the stro...In this paper,we present a surface reconstruction via 2D strokes and a vector field on the strokes based on a two-step method.In the first step,from sparse strokes drawn by artists and a given vector field on the strokes,we propose a nonlinear vector interpolation combining total variation(TV)and H1 regularization with a curl-free constraint for obtaining a dense vector field.In the second step,a height map is obtained by integrating the dense vector field in the first step.Jump discontinuities in surface and discontinuities of surface gradients can be well reconstructed without any surface distortion.We also provide a fast and efficient algorithm for solving the proposed functionals.Since vectors on the strokes are interpreted as a projection of surface gradients onto the plane,different types of strokes are easily devised to generate geometrically crucial structures such as ridge,valley,jump,bump,and dip on the surface.The stroke types help users to create a surface which they intuitively imagine from 2D strokes.We compare our results with conventional methods via many examples.展开更多
基金Supported by Beijing Natural Science Foundation and Key Program of Scientific Planning of Beijing Education Committee (No.KZ200810016007)
文摘The displacements and geometry of the rock blocks and the properties of the rock struc-ture play an important role in the stability of tunnels.Based on the key block model,the dynamic instability analysis of underground tunnel subjected to intensive short-time compressional wave was conducted.The instability of the tunnel caused by the spallation and the inertial effect was distin-guished.And the influence of the roof contour curvature of tunnel was also determined.
基金The research is supported by MOE(Ministry of Education)Tier II project T207N2202and National Research Foundation grant,which is administered by the Media Development Authority Interactive Digital Media Programme Office,MDA(IDMPO).
文摘In this paper,we present a surface reconstruction via 2D strokes and a vector field on the strokes based on a two-step method.In the first step,from sparse strokes drawn by artists and a given vector field on the strokes,we propose a nonlinear vector interpolation combining total variation(TV)and H1 regularization with a curl-free constraint for obtaining a dense vector field.In the second step,a height map is obtained by integrating the dense vector field in the first step.Jump discontinuities in surface and discontinuities of surface gradients can be well reconstructed without any surface distortion.We also provide a fast and efficient algorithm for solving the proposed functionals.Since vectors on the strokes are interpreted as a projection of surface gradients onto the plane,different types of strokes are easily devised to generate geometrically crucial structures such as ridge,valley,jump,bump,and dip on the surface.The stroke types help users to create a surface which they intuitively imagine from 2D strokes.We compare our results with conventional methods via many examples.
