Author = Mohsen Afsahi

Introduce a New Simulation-Based Optimization Model to Integrate Decisions about Products under Warranty and Out of Warranty

Volume 8, Issue 4, Winter 2019, Pages 310-326

Mohsen Afsahi, Ali Hosseinzadeh Kashan, Bakhtiar Ostadi

Abstract In today's competitive market, many products are sold under the basic warranty, and in order to increase profit margins and customer satisfaction after the end of the basic warranty, manufacturers offer warranty extensions to customers at a specific price and time. In this research, the aim is to maximize the producer profit by determining the optimal values of product price, length of basic warranty period, length of warranty renewal, repair level in incomplete repair and amount of spare parts (for demand of products under basic warranty, warranty extension and out of warranty). . In order to better model the real situation, it is assumed that the product can be repaired with three types of minimum, incomplete and complete repairs at the time of failure, and the percentage of products that are repaired each time is also considered as a decision variable. have became. The product reliability function is modeled at the time of incomplete repair with the Kijima virtual life model approach. The problem-solving approach is based on the simulation-based optimization approach in three stages. In the first stage, decision variables such as product price, basic warranty period, warranty renewal period, warranty renewal price, repair level and the probability of what kind of repair each product It is determined by a meta-heuristic algorithm. Then, using Monte Carlo simulation, the number of products that have purchased the warranty extension and the number of product failures is calculated, and finally, the production of spare parts is optimized using a dynamic programming algorithm. This model has also been analyzed for LG vacuum cleaner product and Goldiran after-sales service. 

Integrated Price Optimization, Basic Warranty Policies and Warranty Renewal Taking into Account Products out of Warranty

Volume 8, Issue 1, Spring 2018, Pages 63-74

Mohsen Afsahi, Ali Husseinzadeh Kashan, Bakhtiar Ostadi, Seyed Hessameddin Zegordi

Abstract Today, manufacturers use warranty as an important advertising tool to increase market share. Offering the product to the market with a longer warranty, although attracting more customers, increases the manufacturer's costs. In the real world, manufacturers can provide buyers with an option to renew their warranty for a specified period of time after the end of the basic warranty period. Thus, products that do not renew their warranty as products out of warranty are the main source of profitability of the manufacturer from the sale of spare parts. In this research, a new model is presented that helps the manufacturer to increase profits and considering the level of customer satisfaction and the effect of selling spare parts to products out of warranty, such as pricing of the main product, length of basic warranty period, length of warranty renewal period. Optimize the price of the warranty extension. The developed particle swarm algorithm and the sports league algorithm have been used to solve the model. Due to the fact that Goldiran Company in Iran, as the after-sales service representative of LG, has provided the possibility of extending the basic warranty for products under this brand, the proposed model has been solved with data related to the LED product. The results show that Goldiran Company can help increase the producer profit margin by changing the values of the basic warranty period and extending the warranty according to the product life cycle and planning time, while now the company has fixed the warranty period and extended warranty period for all its products. is considered.