other Mathematical Modeling and Applications of OR Mathematical Modeling and Applications of OR پژوهشی Original <i><span style="font-size:11.0pt"><span new="" roman="" style="font-family:" times=""><span style="color:black"><span style="letter-spacing:-.25pt">Demand planning based on demand data in the supply chain includes the most significant steps in production planning. Therefore, the supply chain&#39;s correct demand forecasting may reduce this effect, known as the bullwhip effect or uncertainty concerning customer demand, thus reducing companies&#39; and organizations&#39; costs and surplus activities. Therefore, this article examined the statistical population characteristics to test the hypotheses through the path analysis drawn using descriptive statistics and FCM(fuzzy cognitive map)&nbsp; method. Then, the model strength was investigated using structural equation modeling (SEM) in AMOS software, and structural equations were presented. This article selected the Aftab oil factory as a case study. The findings of this study emphasized that demand management performance is highly essential for industries. Companies can design the sector independently as a demand management sector for evaluating customer demands at different levels of the supply chain. According to the fit of the main model, CFI and NFI indices are equal to 0.99 and 0.97, respectively, which are close to the optimal fit threshold. RMSEA and SRMR indices are equal to 0.01 and 0.01, respectively, both showing a relatively good fit of the model.</span></span></span></span></i> Supply Chain, Customer Demands, FCM 0ethod, Bullwhip Effect, Surplus Activities, Structural Equation Modeling 96 120 http://iors.ir/journal/browse.php?a_code=A-10-1422-71&slc_lang=other&sid=1 Milad Rezaeefard Milad Rezaeefard milad.rezaeifard@yahoo.com 1111111111 1111111111 No Industrial Management ,Department of Industrial Management, College of management and economics, Tehran Science & Research Branch, Islamic Azad University, Tehran, Iran Industrial Management ,Department of Industrial Management, College of management and economics, Tehran Science & Research Branch, Islamic Azad University, Tehran, Iran Nazanin Pilevari Nazanin Pilevari nazanin.pilevari@gmail.com 1111111111 1111111111 Yes Department of Industrial Management, Islamic Azad university, West Tehran Branch ,Visitor Professor Tehran Science & Research Branch ,Tehran, Iran Department of Industrial Management, Islamic Azad university, West Tehran Branch ,Visitor Professor Tehran Science & Research Branch ,Tehran, Iran Farshad Faezy Razi Farshad Faezy Razi f.faezi@semnaian.ac.ir 1111111111 1111111111 No Department of Industrial Management, Semnan Branch, Islamic Azad University, Semnan, Iran Department of Industrial Management, Semnan Branch, Islamic Azad University, Semnan, Iran Reza Radfar Reza Radfar reza.radfar@uwe.ac.uk 1111111111 1111111111 No Department of Industrial Management ,Science & Research Branch, Islamic Azad University, Tehran, Iran Department of Industrial Management ,Science & Research Branch, Islamic Azad University, Tehran, Iran