Optical Flow Field Estimation Algorithms,one important kind of picture motion estimation as the essential task of video processing,are typically based on the Basic Constraint Equation of Optical Flow Estimation,sponsored by Horn and Schunk,which is in fact not complete due to the lack of enough constraints.

Consistency checking of cardinal direction constraints is one of the essential issues in qualitative spatial reasoning.

Based on the theory of coupling and constraint equation, the paper puts forward a Finite Element model (FEM) of metallic hose with the element of Shell93 and Beam189.

Then,the displacement relation between the nodes in one beam is made up by the constraint equation method.

The constraint equations were established at the common boundary section based on plane section premise.

The rationality of end constraint equations on buckling loads of a drillstring in an inclined wellbore is investigated.

In the new approach, the method of regula falsi is used to solve the constraint equations, instead of the conventional linear approximation.

The motion of the rolling disk was analysed to try to explain some unintegrable equations of constraint which is not definitely independent equation of nonholonomic constraint,and the concept of concealed coordinate was proposed.

The equations of constraint are concerted with ideal constraints.

This article analyses the motion of the rolling disk,trying to explain some unintegrable equations of constraint which is not definitely independent equation of nonholonomic constraint,and put forward the concept of concealed coordinate.