کاربرد برنامه ریزی ریاضی در طراحی مدیریت هزینه با اتخاذ کیفیت عملکرد مهندسی ارزش و هزینه یابی هدف Quality Function Deployment, Value Engineering and Target Costing, an Integrated Framework in Design Cost Management: A Mathematical Programming Approach

In this paper, the need to incorporate three famous design cost management methods, called: Quality Function Deployment (QFD), Value Engineering (VE) and Target Costing (TC) into a single model has been addressed. Each method performs very well in cost management procedures as design activities. These methods have been incorporated into a mathematical programming model, in order to achieve the maximum bene t of each method. The model, essentially, optimizes customer satisfaction subject to target cost. The tool is a mixed integer zero-one nonlinear programming. The uni ed model has been proposed to prevent a non-optimal solution when methods interact with each other. The practitioner should be con dent that the quality solution would be achieved in contrast to when the methods are applied sequentially. A simple automobile design example was formulated and solved to show the performance of the model. INTRODUCTION Considering cost in the design process is an important issue. Many features of a product and ways in which to produce it are determined in the design phase. This encourages careful consideration in all stages of the design activities. Much research has been conducted in this subject through di erent approaches. Many authors studied cost through Quality Function Deployment (QFD) planning [1-3], where others studied this process using the Value Engineering (VE) methodology for design activities [4,5]. Target Costing (TC) is another approach to design cost management [4,6]. All three methods try to manage cost in the design phase and, therefore, achieve competitive produce. The complementary e ect of these methods has been recognized by many researchers. In particular, Cooper and Slagmulder [4], in their book, comprehensively discussed the interaction between the target costing *. Corresponding Author, Department of Industrial Engineering, Tarbiat Modarres University, Tehran, I.R. Iran; Email: fjariri@gmail.com. 1. Department of Industrial Engineering, Tarbiat Modarres University, Tehran, I.R. Iran. method and value engineering. They elaborately present the Survival Zone for a product that consists of three characters: 1. Price, 2. Functionality, 3. Quality. They discussed how these three factors interact with each other and provide the Zone for the operations of the rm. This Survival Zone is presented in Figure 1. The interaction of price and functionality was, also, discussed by them. Here, an attempt has been made to incorporate the third method (QFD) in this set. It is believed that a mathematical model is the proper tool for this incorporation and its feasible region precisely demonstrates the Survival Zone, which was described in [4]. In the following sections, rst, there is a brief explanation of these three methods. Then, a mathematical programming will be introduced to incorporate all three methods in one model, therefore, achieving an optimized result. A numerical example from the automobile industry will accompany the model. 406 F. Jariri and S.H. Zegordi Figure 1. The survival zone for a product source [4]. QUALITY FUNCTION DEPLOYMENT (QFD) QFD is an overall concept that provides a means of translating customer requirements into the appropriate Technical Attribute (TA) for each stage of product development and production. Considering cost into the House Of Quality (HOQ) has been studied by some researchers [7-9]. It provides a tool for cost management in the design phase. Approaching cost to QFD, using mathematical modeling, has also been the subject of di erent articles [1-3]. All articles reported successful experiments when considering cost in the QFD planning.