The single vendor single buyer integrated production inventory problem with lead time proportional to lot size and space restriction is studied. Demand is assumed to be stochastic and the continuous review inventory policy is used for the buyer. If the buyer places an order with lots of products, then the vendor will produce lots of products and the products will be transferred to the buyer with equal shipments many times. Mathematical model for this problem is defined and a Lagrangian relaxation approach is developed.
This paper develops a two-echelon supply chain model with variable setup cost and environmental impact. A single-setup-multi-delivery (SSMD) policy is adopted to increase the efficiency of transportation in the supply chain in which it is assumed that the shipment lot size of each delivery is unequal and variable. Each delivered item goes through inspection process at the buyer’s end. After inspection, defective products are returned to the vendor for reworking process. Due to inspection process, end customers receives perfect quality items. Due to more transportations by SSMD policy, this model assumes carbon emission cost to help the world environment. An investment function is used to reduce total setup cost for the whole supply chain. Stackelberg leadership approach is utilized in this model to optimize the joint total cost of vendor and buyer. Finally, some numerical examples, sensitivity analysis, and graphical representations are given to illustrate more savings from existing literature.
With the increase in elderly population rate, interest in development of equipment to aid for the elderly activities has been increased. Since the physical features of repetitive behavior of elderly people standing and sitting can cause the stress on certain parts of the body, The necessity of developing Lift Chair concerning the foregoing problem has been to the fore. In this study, we set the average body size of the elderly aiming to develop non-motorized Lift Chair, developed Non-motorized tilting mechanism based on the Muscle strength change at knee angle, and did a study relatively inexpensive Lift Chair considering esthetic and practicality.