Coordination of material and information flows in intercity logistics systems

Abstract

The problem of the effectiveness of the use of road transport in logistics systems is considered. Carriers attract additional motor vehicles according to increasing in freight turnover, namely in long-distance routes. The trend of growth in the volume of transportation and the distance of cargo transportation has been maintained in recent years, despite the crisis periods in the economies of the European Union countries. However, the increase in the number of vehicles of fleets is accompanied by an increase in their idle time and delays in the delivery of goods. This phenomenon is explained by the lack of necessary coordination of material flows on the transport network. We considered two types of material flows, namely cargo flows and automobile flows. Both types of flows are discrete in nature. In order to represent the interaction of material flows in the logistics system, the term elementary logistics operation is used, which is the smallest constant element of the logistics chain. Despite the wide variety of processes that occur in logistics systems, the number of typical elementary logistics operations is limited and quite small. For the numerical characterization of material flows, such parameters as a tact, a front, the size of a group of material elements, and the average intensity of the flow are used. Based on the known dependencies between these parameters and taking into account the connections of elementary logistics operations, a structural model of logistics chains is built. It is taken into account that information messages in the logistics system arise when material flows change. The impact of changes in the intensity of cargo flows in logistics chains has been studied and the majority of sources of information messages in space and time have been determined. It has been proven that the use of the objectively necessary amount of information with the necessary advance time makes it possible to reduce dynamic and static delays of cargo flows to a minimum. Due to the fact that changes in the intensity of material flows occur stochastically in logistics chains, the feasibility of assessing the resistance of a given logistics system to external disturbances was developed. The influence of information provision of truck crews performing transport tasks on highway connections is studied. An information support scheme has been developed on the terms of cargo delivery with the need for the truck to arrive at the unloading point on time.