Showing 3 results for Bullwhip Effect
S.k. Charsoghi, A. Sadeghi,
Volume 19, Issue 4 (12-2008)
Abstract
In this paper, a two-echelon supply chain, which includes two products based on the following considerations, has been studied and the bullwhip effect is quantified. Providing a measure for bullwhip effect that enables us to analyze and reduce this phenomenon in supply chains with two products is the basic purpose of this paper. Demand of products is presented by the first order vector autoregressive time series and ordering system is established according to order up to policy. Moreover, lead-time demand forecasting is based on moving average method because this forecasting method is used widely in real world. Based on these assumptions, a general equation for bullwhip effect measure is derived and there is a discussion about non-existence of an explicit expression for bullwhip effect measure according to the present approach on the bullwhip effect measure. However, bullwhip effect equation is presented for some limited cases. Finally, bullwhip effect in a two-product supply chain is analyzed by a numerical example.
Sajjad Aslani Khiavi, Hamid Khaloozadeh, Fahimeh Soltanian,
Volume 32, Issue 1 (1-2021)
Abstract
In this paper, discrete time dynamic model for four-level supply chain system, including factory, wholesaler, retailer, and customer is designed with a recovery center as recycling hybrid channels. Due to the lack of coordination of the chain level and the unhealthy exchange of information in the system, almost all supply chains dynamic involving the stochastic noise. For the first time, in this paper, we proved that stochastic noise lead to the bullwhip effect and we mitigated this phenomenon with control theory. Also, we investigate the effects of the lead time, the various forecasting methods, and aggressive ordering on the bullwhip effect. In order to mitigate the bullwhip effect, we propose Kalman filter method. So, using linear quadratic Gaussian controller, not only effect of bullwhip was adjusted but, also the system become stable. Eventually, the simulation results in Meshkin match factory, indicate the efficiency of the proposed method.
Ahmad Lotfi, Parvaneh Samouei,
Volume 34, Issue 3 (9-2023)
Abstract
As efficient instruments, there have been increasing studies on contract optimization in the supply chain field over the recent two decades. The lack of review papers is one of the gaps in contract optimization studies. Hence, the extant study aimed to provide researchers with an attitude to direct future studies on this topic. Therefore, the collected studies on contract optimization were reviewed and analyzed primarily. Then papers were classified based on the selected categories and themes. Finally, evaluation and results were presented based on the classified topics. They conducted studies, then achievements and limitations of the literature and future research opportunities were introduced to pave the way for researchers’ further studies.
