where RI is the consistency index of a

reciprocal matrix, randomly generated from the 9-point scale.

In AHP, the paired difference is measured by the ratio scale and correspondingly P is a pairwise

reciprocal matrix (PRM).

8), which is the average CI of a randomly generated

reciprocal matrix. CI=0 indicates perfectly consistent matrix, otherwise, CI should be positive.

Attention: A should satisfy the following properties: [a.sub.ij] > 0, = [a.sub.ij], and [a.sub.ii] = 1; A is called positive

reciprocal matrix.

The consistent completion of a

reciprocal matrix as a mechanism to obtain a consistent body of opinion issued in an incomplete manner by a specific actor was addressed.

The matrix is called the fuzzy positive

reciprocal matrix, MM = [[[m.sub.ij]].sub.n*n].

Saaty [21] demonstrated that for consistent

reciprocal matrix, the largest eigenvalue is equal to the number of comparisons, or [[lambda].sub.max] = n.

matrix A represents a

reciprocal matrix, [a.sub.ij] is the inverse of the entry [a.sub.kj] which indicates the relative importance of [C.sub.i] compared with attribute [C.sub.j].

Where matrix A represents a

reciprocal matrix, [a.sub.ij] is the inverse of the entry [a.sub.kj] which indicates the relative importance of [C.sub.i] compared with attribute [C.sub.j].

It is known that the maximum eigenvalue of the

reciprocal matrix of range m is [[lambda].sub.max]=m (Saaty 1980).

(3) Measurement consistency It is necessary to measure the level of consistency of the

reciprocal matrix by a consistency index (CI).

So, the

reciprocal matrix A of average acoustic velocity in each block can be calculated as