Method of optimizing parameter values in a process of producing a product

Abstract

A method of optimizing parameter values in a process, which process is essentially controlled by a set of parameters affecting a set of properties characterizing an output of the process. The method may use an analytic hierarchy process (AHP) to associate a weight with each property according to its relative importance to obtain desired product characteristics. The method also uses parameter data and measured property data from a required number of experimental runs of the process, from which data property behavior relations between each property and the parameters are statistically established, which relations give estimated property values. Using the property weights, a process goal function is established, which is expressed in terms of weighted deviations between the estimated property values and the corresponding goal values for the properties. The process goal function is minimized in order to generate a set of optimal parameter values for the process.

1 . A method of optimizing parameter values of a process, the process being essentially controlled by a set of n parameters X that affect a set of k properties Y characterizing an output of the process, said method comprising: 
 assigning values to a set of k property weights representing relative importance of said properties;    establishing property behavior mathematical relations giving an estimated property for each said property;    using said property weights to establish a goal function in terms of property weighted deviations between the estimated properties and corresponding specified goal values for said properties; and    minimizing the goal function to generate a set of n optimal parameter values for said parameters.    
   
   
       2 . A method according to  claim 1 , wherein the values for said property weights are obtained using an algorithm based on an analytic hierarchy process.  
   
   
       3 . A method according to  claim 2 , wherein said given property data are obtained through a number of experimental runs of said process using said given parameter data, each said run using a distinct set of values for said given parameter data.  
   
   
       4 . A method according to  claim 1 , wherein the number is one more than the number of parameters X.  
   
   
       5 . An apparatus capable of optimizing parameter values of a process, the process being essentially controlled by a set of n parameters X that affect a set of k properties Y characterizing an output of the process, said apparatus comprising: 
 means for assigning values to a set of k property weights representing relative importance of said properties;    means for establishing property behavior mathematical relations giving an estimated property for each said property;    means for using said property weights to establish a goal function in terms of property weighted deviations between the estimated properties and corresponding specified goal values for said properties; and    means for minimizing the goal function to generate a set of n optimal parameter values for said parameters.