الگوی انتخاب تامین کننده: متدولوژی QFD سلسله مراتبی یکپارچه تحت محیط چند معیاره

A concurrent engineering approach integrating analytic hierarchy process (AHP) with quality function deployment (QFD) in combination with cost factor measure (CFM) has been delineated to rank and subsequently select candidate-suppliers under multiple, conflicting-in-nature criteria environment within a value-chain framework. Engineering requirements and customer requirements governing the selection decision have been identified. The hierarchical QFD methodology allows the decision maker (DM) to rank the candidate-suppliers considering both CFM and the subjective factors. The sensitivity of the proposed methodology is elucidated considering a parameter called objective factor decision weight. The devised methodology has been tested with the dataset adopted from Yahya and Kingsman [89]. Liu and Hai [51] tested their model with the same dataset. A comparative analysis using design of experiment has been elucidated so as to demonstrate the efficacy of the devised hierarchical concurrent engineering approach.

Supply chain management is a process of planning, implementing, and controlling the operations of the supply-chain network catering to the requirements of customers (purchasers) as efficiently as possible. One of the primary activities of a value chain model [62] is to provide service to the customers thereby adding value to the value-chain network. Further, the goal of any organisation is to maximise the value creation while minimising the costs. Thus, selection of a supplier plays a crucial role in a value chain, or present days’ supply-chain network of any organisation as it demands trading off among cardinal and ordinal preferences of the decision makers (DM) in an optimal way. The supplier selection process is the most significant variable in the effective management of modern supply-chain networks as it helps in achieving high quality products and customer satisfaction [33]. Effective supplier selection calls for robust analytical methods and decision support tools [57] that are able to trade off multiple subjective and objective criteria. In an exhaustive review of 76 articles Weber et al. [84] found that 47 address involvement of more than one criterion [84]. Dickson [28] identifies a set of 23 criteria considered by purchasing managers under different supplier selection scenario. A supplier selection decision is inherently a multi-criteria problem and a decision of strategic importance to companies [41]. Thus, the selection decision within a supply-chain framework is a complex process involving multiple criteria. Supplier selection decisions within a supply-chain network are complicated as potential options for such selection decisions are evaluated on more than one criterion [85]. Criteria may vary depending on the type of product being considered and include many qualitative factors in addition to the quantitative criteria [81]. Therefore, supplier selection is a multi-criteria decision-making problem which includes both qualitative and quantitative factors [88] and [92]. This paper addresses the relationship among the criteria for supplier selection decision-making. Both cardinal and ordinal preferences have been considered for evaluation of candidate-suppliers. In a supply-chain framework such decision-making involves cost factors. Thus, cost factor components have been included and a trade off among all the criteria has been established integrating the quality function deployment (QFD) technique [1] suitably with analytic hierarchy process (AHP) [69] and [70]. Supplier selection is viewed as a combination of both customer requirements and engineering requirements. Customers are the companies that purchase the technical expertise of the suppliers. Therefore, such a company–supplier relation can be viewed as a ‘house of quality’ model. The outcome of the integrated methodology presented in this paper is determined with indices trading off all the types of information available within the supply-chain framework. The remainder of the paper is organised as follows: Section 2 presents a survey of existing literature in the field of supplier/vendor selection. An attempt has been made in this regard to classify the tools/methodologies used in evaluating the suppliers within the scope of the research. This leads framing of the research objectives in the later part of Section 2. QFD and AHP techniques have been briefed and subsequently the proposed integrated hierarchical methodology for supplier selection is delineated in Section 3. Section 4 is directed towards the development of the case study, interaction of criteria, sub-criteria and cost factor components relevant to the selection decision. The devised methodology has been implemented in a real-world problem adapted from Yahya and Kingsman [89] and Liu and Hai [51] in Section 5. Section 6 provides comparative analyses of the results obtained which are further directed to ascertain the scope for future work. Finally, Section 7 concludes with the criticism of the supplier selection process.

The devised concurrent engineering methodology allows the ill-structured supplier selection problem to be tackled in a more structured hierarchical manner. It is evident from the results, analysis and the discussion outlined in the previous sections that the process presented in this paper is a feasible, useful and practical for ranking candidate-suppliers in real-world situations. The proposed methodology is unique in the sense that an OR approach has been associated with QFD so as to hear the voice of the customers in a supply chain scenario. The strength of the proposed methodology lies in allowing DMs to avoid other cumbersome techniques when a simple, purchaser/supplier-friendly efficient algorithm is readily available. The hierarchical QFD method enhances the effectiveness of the purchasing decisions for the company. It assists the purchaser in solving the right problem. The integrated method is so flexible that it can accommodate more criteria and sub-criteria if desired. Further, the method provides for the space for new hierarchies that may result from the inclusion of any new and relevant criteria and sub-criteria for purchasing decisions. But adequate care must be taken while adding up criteria and sub-criteria so that issues of rank reversal and preference reversal within the hierarchical framework do not arise. The proposed methodology allows the purchaser to segregate the criteria according to the problem needs. This filters out non-relevant criteria and sub-criteria while making purchasing decisions and enable the DM to check redundancy of criteria and candidate-alternatives. Moreover, the proposed model aids the purchaser to model the decision situation more precisely considering specifically both the intangible and tangible factors. Incorporation of the groups’ decisions is one of the flexibilities of the proposed methodology. The model allows the DM to visualise the decision variables’ responses to a slight variation in the decision weights. Enhancement of the computation time by automated computation and faster analysis of decision-making information is possible with the proposed model. Finally, the proposed hierarchical QFD methodology facilitates efficient communication between the suppliers and purchasers.