Development of a dynamic model of decision-making delays in the logistics chains of urban freight traffic

Abstract

The directions of application of methods of dynamic modeling of delays in decision making in logistic chains of urban freight transport are considered. The main difference of the developed model from the previously known, is that the model operates in real time mode and using Internet resources determines the traffic of sections of the road network or the presence of traffic jams. The task of identifying a dynamic mathematical model of delays in decision making at a logistics center and a transport company when receiving an application for the carriage of goods is reduced to the definition of the operator of the model. Under the operator of the model, we will understand the mathematical dynamical model in the form of linear differential equations of the second order. The dynamic model of delays in making decisions in the logistic chains of urban freight transport is developed. As a result of structural identification, the second-order differential equation and its solution are obtained, which allows to simulate the dynamics of the process of handling requests for transport services and the process of transport service itself in logistics chains. The parametric identification of the developed model is fulfilled, an expression is obtained for determiningthe gain and constant time coefficients that are included in the mathematical model. The physical content of the gain coefficients is determined - this is the sensitivity of the logistical circuits and the system as a whole before receiving maintenance requests and is characterized as a stock of performance. The physical content of the boost factor of the logistic system (LS) is the sensitivity of the LS to the performance of transport services. If the gain of the drug is less than one, then applications received in the drug will be in line and the service time will increase significantly. Physical content of constant time - is the inertial properties of logistics chains, which form a delay in the decision making on transport services. The great importance of the constant time of the logistics center suggests that the logistics center has a high degree of inertia in accepting applications and will have a long delay. Physical content of the constant time of a transport enterprise is the time from the fact of transferring an application for transport from the logistics center to the transport enterprise until the time of the beginning of the traffic on the route. Consequently, the value of the constant time of the transport enterprise characterizes the inertia of the transport company, and hence the delay in processing the application. The time of movement of vehicles along the route is also included in the value of the constant time of the transport enterprise. It is shown that the total time of delivery of cargo consists of the time of finding the vehicle in the route, taking into account the resistance of the route and the time delays in all logistics chains of the system.