The sequence is calculated by relative approximation,giving rock of the same class in quality sequence.

On the basis of introducing the concept of gray correlation degree into traditional TOPSIS,the author combined the Euclidean distance with gray cor-relation degree and established a new kind of relative similarity degree to decide the quality of alternatives.

This method established a new kind of relative similarity degree by combining the Euclidean distance with grey correlation degree.

Then the relative similarity degree of each stage was calculated,finally the comprehensive similarity degree was obtained according to the time weight.

The distances between the schemes and both the positive and negative ideal solutions are defined in accordance with the similarity to determine the relative closeness coefficient of various schemes, thus obt.

Based on the relative closeness between decision alternative and ideal solution,and the objective functional satisfactory scale,an interactive multi-objective decisionˉmaking method is given,a practical ex-ample is given to show the rationality of this method.

In multiple criteria decision making, the shortcomings of the existing double base points methods are pointed out, a new relative closeness to ideal point is defined based on the criteria near ideal point and far from negative ideal point, and a generalized double base points method is provided in this paper.

The method uses the inclination to define the relative closeness between decision alternative and ideal point.

The peculiarities of this method include the establishment of the membership functions of the non quantitative factors by analogy method,determination of the weight value of each factor according to its significance by the analytic hierarchy process (AHP),use of the weighted average model in evaluation and classification of the grade of pile foundation by the asymmetric approach degree method.