Optimization procedures of modern supply chains often require the consideration of a number of special factors that must reflect simulated cash flows so that the solutions found meet academic requirements in inventory management. The article evaluates the profitability of deliveries for the modified EOQ-model, in the format of which it will be possible to envisage the impact of the following factors. 1) The previously agreed possibility of deferring payment for an order. 2) The concept of the time value of money in the analysis of the cash flows of the simulated supply chain. 3) For incoming payments it is necessary to take into account that the proceeds from the sold goods will arrive with a predetermined delay (from the mo-ment of its realization time). 4) The payment of storage costs is realized in the form of leasing the corresponding places in the warehouse, and with a delay for a specified time in relation to the middle of the reordering interval (in contrast to the traditional theory positions in the format of classical EOQ-models of inventory management).
In the case of such models, the existence of an estimate for the cost-effectiveness of the cash flows of the simulated supply chain will make it possible to use the new modified EOQ formulas taking into account the abovementioned factors. This will allow to optimize the reserves taking into account the time value of money in accordance with the requirements of financial analysis and financial mathematics. The research was carried out in relation to important for business situations of efficient supply, when the specified deferrals for payment of an order allow you to pay it out of the pro-ceeds at the reorder intervals. Therefore, in order to simulate such processes, a necessary and sufficient condition has also been established in the paper, that must be imposed on the duration of such a delay in order to ensure the possibility of the specified pay-ment of the order from the proceeds. The modification of such conditions is presented if, during optimization, it is necessary to take into account the need for payments from the revenue for payment of storage costs, as well as the required additional deductions related to maintaining the business processes. The features of supply optimization procedures are illustrated on the basis of numerical simulation results.
The article presents the derived formulas for calculating the parameters of the EOQ model that takes into account simultaneous multi-product supplies and differential discounts as well as the developed algorithm for calculating the parameters of this model.
The sections of the discipline "Economic and mathematical methods and models in logistics" are presented, related to procedures for optimizing supply chains on the basis of methods of mathematical theory of inventory management, methods and models of graph theory, methods for solving the transport problem, methods for optimizing flows in networks, optimizing network project schedules. The foundations of the method of simulation are given.
The article summarizes the results of optimization of the inventory management strategy, taking into account the joint impact of factors that are important for the practice: the cargo capacity of the vehicle, delays in payment for the cost of goods, delays in payment for storage costs, delays in payment for the cost of delivery of goods. A new modification of the EOQ-formula is presented, which will allow to take into account the specified specificity of the supply chain operation.
Russian mining industry experiences a rapid growth providing an attractive market for suppliers of mining equipment. However, it's a customer-dominated market. The customers set stringent requirements for the initial equipment supply, as well as for the after-sale service and spare parts supply. The manufacturers of mining equipment are thus facing the need to rigorously analyze their supply chain, to develop a reasonable customer service policy and to adjust the supply chain to meet the requirements of the service policy. To fulfill the after-sale maintenance requirements, the manufacturers must stock spare parts within the supply chain and to design inventory control policies. This paper presents an agent-based simulation approach for estimation of the supply chain's key performance indicators and to explore the service - cost trade-off. The conceptual model and the description of its implementation in Anylogic 8.4 software are provided. A case-study of a global mining equipment manufacturer's branch operating in Russia is described. The model is used to estimate the inventory control policy parameters required to meet the target customer service level, to compare make-to-order against make-to-stock supply strategies, as well as to explore the service level - cost trade-off.
The purpose of this paper is to research multicriteria decision-making optimisation problems of logistics systems and supply chains considering conditions of uncertainty. The article presents an approach that allows adapting the procedures of multicriteria optimisation to the format of conditions of uncertainty. This approach is relevant for the situation when a manager does not have reliable estimates for the probability of random events and cannot use decision-making methods under risk conditions. The study proposes the synthesis of optimisation procedures, including the format of the multiple criteria decision-making theory and the format of procedures developed in the theory of decision-making in conditions of uncertainty. The specifics of this approach and algorithm for optimising such solutions are presented according to the inventory management problem.