A METHOD TO FORM CONTROL OVER QUEUING SYSTEMS TAKING INTO CONSIDERATION THE PROBABILISTIC CHARACTER OF DEMAND

Queueing systems (QS) belong to the class of systems the quality of control over which cannot be assessed in real time. In other words, it is impossible to apply methods of classic search optimization at the stage of control design. The current practice of control design implies the acquisition of historical data required to model an operational process in order to choose its best control parameters. These parameters include: determining the size of the planning horizon, forecasting interval, the type of a forecasting model. All these parameters represent the degrees of freedom of search optimization. Upon defining these parameters, modeling process is repeated for different values of shift in the demand forecasted value towards the region of large positive values. Such a shift leads to an increase in the QS inventory levels and a decrease in the likelihood of a product deficit occurrence. Process efficiency is compromised by both the insurance stocks and a shortage of products. However, experience has shown that a certain shift in control towards an increase in the inventory levels improves the efficiency of their functioning. Thus, the task on QS inventory control implies the substantiation of choice of control parameters in the process of cyclic simulation of the operational process based on the set of historical data. Despite the long history of the subject, there is no method at present whose application would make it possible to obtain control, the parameters of which could be considered justified. This relates to that the best control parameters are determined not by examining the quality of economic models of an operational process but rather by studying the quality of quantitative models of this process. In order to further advance the theory and methods of control, we have constructed an economic-mathematical model of uncoordinated operation. The model proposed takes into consideration the result of interaction between processes in the buffering channel and processes in the client channel that aims to meet customer demand considering a factor of information impact from marketing technologies on the internal and external consumer. The structure of the constructed mathematical model has passed the validation procedure for consistency, in the process of comparing the redundant and deficient operations. A procedure for estimation optimization of the simulated process has showed a possibility to determine the optimal control parameters based on the criterion for a maximum criterion of efficiency of operational proces