The transverse section of piston skirt is not a standard circle and is with high precision. So the section curve should be interpolated through the high accuracy method of circular arc interpolation before NC machinin...The transverse section of piston skirt is not a standard circle and is with high precision. So the section curve should be interpolated through the high accuracy method of circular arc interpolation before NC machining. In order to smooth the connection of adjacent arcs and shorten the NC machining program, an interpolation method based on Chebyshev theory of function approximation is proposed here. According to the analysis of the interpolation error, the algorithm is simple and with high precision. By this way the fewest interpolating circular arc segments can be got, and the manufacture requirement is satisfied with the circular arc interpolating curves.展开更多
This paper investigates the relative 1-canonical images of non-hyperelliptic fibrations of genus 4. It is proved that if a fibre of the relative 1-canonical image ∑ is not a complete intersection in 3 , then the var...This paper investigates the relative 1-canonical images of non-hyperelliptic fibrations of genus 4. It is proved that if a fibre of the relative 1-canonical image ∑ is not a complete intersection in 3 , then the variety ∑ cannot be smooth on this fibre. Moreover, two examples are given to show the occurrence of such cases.展开更多
文摘The transverse section of piston skirt is not a standard circle and is with high precision. So the section curve should be interpolated through the high accuracy method of circular arc interpolation before NC machining. In order to smooth the connection of adjacent arcs and shorten the NC machining program, an interpolation method based on Chebyshev theory of function approximation is proposed here. According to the analysis of the interpolation error, the algorithm is simple and with high precision. By this way the fewest interpolating circular arc segments can be got, and the manufacture requirement is satisfied with the circular arc interpolating curves.
文摘In this paper the author proves that the Phragmen Lindelof principle holds for solutions of elliptic equation (1) with nonstandard growth conditions.
文摘This paper investigates the relative 1-canonical images of non-hyperelliptic fibrations of genus 4. It is proved that if a fibre of the relative 1-canonical image ∑ is not a complete intersection in 3 , then the variety ∑ cannot be smooth on this fibre. Moreover, two examples are given to show the occurrence of such cases.
