p. samouei

Growing natural disasters such as oods, earthquakes, war, and terrorist attacks have encouraged the government to plan for crisis response situations. As an important crisis management activity, the humanitarian supply chain can play a key role in saving lives, transporting victims to emergency centers, evacuating the homeless from the aected area, and meeting the needs of those in crisis. Also, considering coordination between the members of the supply chain and using suitable contracts can increase the eciency of helping injured people. In previous research, the quantity exibility contract (QFC) is rarely used in crisis situations. Therefore, this contract is investigated in this study. In the present study, a QFC is concluded between the internal supplier (manufacturer) and the relief organization. Quantity exibility contract provides a kind of coordination for inventory management by determining the number of orders between the relief organization and the internal manufacturer. In this study, the purpose of signing a quantity exibility contract between the relief organization and the supplier is not only to satisfy more demand points in the event of a disaster but also to reduce the unused items of relief items after the disaster attacks, and to create fewer shortages in the aected areas. The components of the supply chain of several products presented in this research include an internal supplier (manufacturer) and a foreign supplier, the relief organization, and the points of demand (aected areas). Due to the crisis, the demand for the aected areas has been considered inde nitely. The objectives of the model minimize total costs and time. To solve the proposed model, the augmented "-constraint method is used. The results of the studies show that the model is more sensitive to changes in demand, which makes it more necessary for planners in this eld to be more careful about the demand parameter.

Knowledge transfer can occur on two levels: intra-organizational and inter-organizational. Acquiring knowledge from outside an organization usually requires significant budget and considerable time. However, through awareness and reliance on knowledge already acquired by the personnel, and creating a knowledge flow network, knowledge level of the organization can be increased in the shortest possible time. The present paper addresses the design of a knowledge flow network between the personnel of an organization according to the professional and personal trust levels, teaching and learning capabilities, knowledge level of the personnel, organizational commitment level, type and importance of each knowledge, and the stochastic nature of the knowledge transfer duration. This problem was formulated as a stochastic multi-objective mixed-integer programming. The objectives of the proposed model were maximizing the knowledge level and minimizing the knowledge transfer time. The model was solved using the Lagrangian relaxation algorithm and the CPLEX solver. Results indicate the high efficiency of the Lagrangian relaxation algorithm specially in computational time of large-sized problems. Moreover, the results show that the organizational commitment parameter has more significant influence on the knowledge transfer duration, followed by teaching and learning capabilities.

The bullwhip effect in the supply chain could lead to fluctuations such as extra inventory and delayed order. In the meantime, proper demand forecasting can significantly resolve these fluctuations by eliminating the bullwhip effect. The present study considers forecasting of retailer demand, suppliers and calculates the bullwhip effect in the two-level supply chain. Markov switching model and autoregressive model along with moving average are used to predict retail demand and supplier, respectively. The results showed that the lot size policy-based ordering system can reduce or completely remove the bullwhip effect. Besides, the bullwhip effect is appeared in both levels of the supply chain during utilizing the rm(q0,Qm) order-point policy-based ordering system.