Based on the theorems on linear dependence,linear independence,linear space and relevent theories concerning generation of sub-space in advance algebra,two theorems are given to determine whether the spatial straight lines,presented by the vector-type parametric equations are coplanar or not.

This algorithm includes the following steps in turn: calculating direction vectors generated by a random mesh vertex and the ones around it; recognizing and simplifying the planar areas in the mesh according to vector average angle; judging whether a vertex accords with the secure culling rule, which adopts the result whether the area where this vertex lies is smoo.

The new algorithm adds a direction vector to every depth pixel in LDI ,and creates images from new vantage points by adopting a weighted rendering method for pixels with the same depth.

Fast nearfield beamforming algorithm based on the Fourier series approximation of the steering vector;

It was previously shown that the number of array elements must exceed the number of sources for subspace-based steering vector estimation.

Fourth-order cumulant based on blind beamforming algorithm contained error in estimating steering vector of expected signal,which resulted in degraded capability of minimum variance distortionless response(MVDR) beamformer.

Iris feature extraction algorithm based on wavelet transform and directional vector;

By employing the spatial signature comprehensively, we proposed a novel noise resisting method which is based on a simple DOA method and uses directional vectors and compared this method with those in reference [1] and [2].