期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
S形加减速算法前瞻处理研究 被引量:11
1
作者 朱明 游有鹏 何均 《小型微型计算机系统》 CSCD 北大核心 2011年第10期2140-2144,共5页
由于S形加减速算法的表达式是分段表达式且包括无理表达式,在应用S形加减速算法进行前瞻处理时出现了两个问题:1、方程表达式难以确定;2、需要求解无理方程.针对第一问题,提出一种仅需要少量计算和比较的方法.为了求解无理方程,本文提... 由于S形加减速算法的表达式是分段表达式且包括无理表达式,在应用S形加减速算法进行前瞻处理时出现了两个问题:1、方程表达式难以确定;2、需要求解无理方程.针对第一问题,提出一种仅需要少量计算和比较的方法.为了求解无理方程,本文提出使用拉格朗日逼近法构造二次方程来逼近无理方程,详细分析了逼近产生的误差并给出一种误差校正的方法.文中提出的方法在Matlab平台仿真实现,并已通过实际加工NURBS曲线验证可行. 展开更多
关键词 S形加减速 前瞻 拉格朗日逼近法 数控系统
下载PDF
A hybridized weak Galerkin finite element scheme for the Stokes equations 被引量:10
2
作者 ZHAI QiLong ZHANG Ran WANG XiaoShen 《Science China Mathematics》 SCIE CSCD 2015年第11期2455-2472,共18页
In this paper a hybridized weak Galerkin(HWG) finite element method for solving the Stokes equations in the primary velocity-pressure formulation is introduced.The WG method uses weak functions and their weak derivati... In this paper a hybridized weak Galerkin(HWG) finite element method for solving the Stokes equations in the primary velocity-pressure formulation is introduced.The WG method uses weak functions and their weak derivatives which are defined as distributions.Weak functions and weak derivatives can be approximated by piecewise polynomials with various degrees.Different combination of polynomial spaces leads to different WG finite element methods,which makes WG methods highly flexible and efficient in practical computation.A Lagrange multiplier is introduced to provide a numerical approximation for certain derivatives of the exact solution.With this new feature,the HWG method can be used to deal with jumps of the functions and their flux easily.Optimal order error estimates are established for the corresponding HWG finite element approximations for both primal variables and the Lagrange multiplier.A Schur complement formulation of the HWG method is derived for implementation purpose.The validity of the theoretical results is demonstrated in numerical tests. 展开更多
关键词 hybridized weak Galerkin finite element methods weak gradient weak divergence Stokes equation
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部