Firstly,the paper improves the encapsulation of differential L-system for Bézier surface,then designs a general algorithm of fruit growth modeling,at last implements a complete model of the growth process of orange and apple fruit,whose results indicate that the method is very effective.

Using of a new approach which makes use of a global sub-differential (L-sub-differential),and explicit descriptions for quadratic functions,a sufficient condition to characterize a local optimal solution to be global is established.

Calculation of ray trace in bending fiber with numerical differentiation

The first and second derivatives of the coordinates of a cam profile are calculated using numerical differentiation method,and substituted with curvature radius formulas in calculus,thus obtaining its curvature radius.

Based on studying the way of polar moment of inertia,a new method of major and minor axis detecting by DDA was provided.

Δu+u3=0,in Ω;u=0,on Ω,the method s efficiency has been improved based on search extension method and parameter differential method.