The Improvement Of AHP Method And Its Application In The Selection Of EAF Power Supply Curve

AHP method,as a kind of MCDMs,has been widely used in many fields of economy and society because it is practical,systemic,simple and can deal with qualitative and quantitative issues in the process of decision making.However,like any other theories under developing,AHP method itself is not perfect,and some existing theories still have shortcomings,which need to be improved and perfected.So based on the previous work,this paper analyzes and studies the disadvantages of deriving priorities methods and consistency improving methods in AHP,and the main content includes the following aspects:Firstly,some previous works have shown that the priorities deriving from the EM method do not meet the condition of COP criterion,and it really is an disadvantage of the EM method.This paper improves this disadvantage by the way of establishing optimization model and adopting the GA method to find the optimum solution.The improved priorities can meet the condition of COP criterion and therefore can contain more information in the judgment matrix and can be more in line with the wishes of the decision makers.Then,this paper introduces an existing method which is K-factor method to improve consistency of judgment matrix.This method has some disadvantages such as more iterations,more elements to be modified and larger amount of element modification.In this paper,an optimal model is established and solved by GA method to find the optimal modification amount in iterative process which can be treated as an improved method.Compared with the original method,the number of iterations,the number of element to be modified and the amount of element modification are significantly reduced,so the improved method can retain more decision maker's original judgment information and can be more in line with the wishes of decision makers.The improved method is a reasonable and effective consistency improving method.Finally,the AHP method is applied to the selection of EAF power supply curve.According to the application steps of AHP method,this paper take the lowest cost of smelting as the decision objective and analyze the characteristics of EAF steelmaking and find various factors which can affect the smelting cost.According to the dominant relationship among these factors,the hierarchical structure of power supply curve is established.Using this structure and some specific information and requirements in the actual steelmaking process,a best scheme with the lowest cost can be selected from many alternative power supply schemes to guide the production before smelting.In order to demonstrate the effectiveness of this method,an example of EAF steelmaking in a certain plant is exhibited to explain the specific process of selecting power supply curve by this method.