Method for improving computations of correlation values between surface roughness and terrain parameters

A computer system that generates an improved correlation graph that shows correlations between a surface roughness and terrain parameters of a lunar surface, the computer system comprising:

• a processor;
• a display;
• a non-transitory computer-readable medium having stored therein instructions that when executed cause the processor to:
• apply the terrain parameters as an input of a Back Propagation Neural Network (BPNN) and the surface roughness as an output of the BPNN, wherein the BPNN includes an input layer, a hidden layer and an output layer;
• implement a nonlinear mapping from the input to the output of the BPNN;
• generate a weight matrix (ω1) between the input layer and the hidden layer and a weight matrix (ω2) between the hidden layer and the output layer;
• compute correlation values by:
• calculating a correlation matrix by ω2×ω1;
• calculating a unit weight which is a sum of absolute values in the correlation matrix;
• and
• dividing each value in the correlation matrix by the unit weight;
• and
• generate the improved correlation graph on the display by plotting the correlation values against the terrain parameters.

A method that generates an improved correlation graph that shows correlations between a surface roughness and terrain parameters of a lunar surface, the method comprising:

• applying, by the computer system, the terrain parameters as an input of a Back Propagation Neural Network (BPNN) and the surface roughness as an output of the BPNN, wherein the BPNN includes an input layer, a hidden layer and an output layer;
• implementing, by the computer system, a nonlinear mapping from the input to the output of the BPNN;
• generating, by the computer system, a weight matrix (ω1) between the input layer and the hidden layer and a weight matrix (ω2) between the hidden layer and the output layer;
• computing, by the computer system, correlation values by:
• calculating a correlation matrix by ω2×ω1;
• calculating a unit weight which is a sum of absolute values in the correlation matrix;
• dividing each value in the correlation matrix by the unit weight;
• and
• generating, by the computer system and on a display, the improved correlation graph by plotting the correlation values against the terrain parameters.