Purpose This study aims to propose a new genetic algorithm for solving supply chain scheduling and routing problem in a multi-site manufacturing system. The main research question is: How is the production and transportation scheduled in a multi-site manufacturer? Also the sub-questions are: How is the order assigned to the suppliers? What is the production sequence of the assigned orders to a supplier? How is the order assignment to the vehicles? What are the vehicles routes to convey the orders from the suppliers to the manufacturing centers? The authors’ contributions in this paper are: integration of production scheduling and vehicle routing in multi-site manufacturing supply chain and proposing a new genetic algorithm inspired from the role model concept in sociology. Design/methodology/approach Considering shared transportation system in production scheduling of a multi-site manufacturer is investigated in this paper. Initially, a mathematical model for the problem is presented. Afterwards, a new genetic algorithm based on the reference group concept in sociology, named Reference Group Genetic Algorithm (RGGA) is introduced for solving the problem. The comparison between RGGA and a developed algorithm of literature closest problem, demonstrates a better performance of RGGA. This comparison is drawn based on many test problems. Moreover, the superiority of RGGA is certificated by comparing it to the optimum solution in the small size problems. Finally, the authors use real data collected from a drug manufacturer in Iran to test the performance of the algorithm. The results show the better performance of RGGA in comparison with obtained outputs from the real case. Findings The authors presented the mathematical model of the problem and introduced a new genetic algorithm based on the “reference group” concept in sociology. Robert K. Merton is a sociologist who presented the concept of reference groups in society. He believed that some people in each society such as heroes or entertainment artists affect other people. The proposed algorithm uses the reference group concept to the genetic algorithm, namely, RGGA. The comparison of the proposed algorithm with DGA and the optimum solution shows the superiority of RGGA. Finally, the authors implement the algorithm in a real case of drug manufacturing and the results show that the authors’ algorithm gives better outputs than obtained outputs from the real case. Originality/value One of the major objectives of supply chains is to create a competitive advantage for the final product. This intension is only achieved when each and every element of the supply chain considers customers’ needs in every function of theirs. This paper studies scheduling in the supply chain of a multi-site manufacturing system. It is assumed that some suppliers produce raw material or initial parts and convey them by a fleet of vehicles to a multi-site manufacturer.

Purpose Nowadays, many organizations use quality function deployment (QFD) in order to recognize their customers’ wants and arrange a set of corrective activities in order to satisfy these wants. In a competitive environment, two or more organizations cooperate in order to meet their customers’ wants. The purpose of this paper is to introduce a new hybrid approach of QFD employing SERVQUAL method, named three-dimensional house of quality (3DHOQ) to help the cooperation between two organizations with common customers by determining some common corrective activities that would satisfy their customers’ wants. Design/methodology/approach In order to better explain the proposed model, it is implemented in Birjand International Airport and Iran Air airline. At first, the customers’ want in the airport and airline sections are identified and the SERVQUAL method is used to determine the final weight of these wants. Afterwards, the corrective activities for satisfying the customers’ wants are determined using the three-dimensional QDF; and then are given weights using the multi-dimensional relation matrix. Findings Results of this study show the customers’ wants in two sections of airport and airline, the importance of each customer want, the gap between customers’ perception and expectation of each want, the collective corrective activities required to satisfy the customers’ wants and the weight of these corrective activities. Research limitations/implications This paper helps the airline and airport sections have an analyzed list of their customers’ wants and a set of shared and unshared corrective activities to meet these wants. Originality/value This paper presents a simultaneous QFD analysis in the airport and airline sections. Moreover, a new hybrid approach employing SERVQUAL method, named 3DHOQ is introduced to determine the corrective activities of both organizations and their weights.