Optimization of the parameters of the urban freight transport process

Abstract

A methodical approach to optimizing the parameters of the transport process of the urban freight transportation has been developed. The approach is based on a cumulative unit cost model that takes into account three components .
The first component depends on the fare, the length of the route, the weight of the goods transported, as well as the technical speed of the movement, the frequency of receipt of requests for transport service and the coefficient of reliability of the transport service. The reliability factor takes into account the delays of the car on the route, as well as the presence of traffic jams on the route.
The second component of unit costs depends on the number of vehicles in the outfit, the technical speed of the movement, the total time of transport service, the fuel consumption and its price, as well as the mass of the freight, mileage coefficients, the car's load utilization coefficients and the reliability factor.
The third component depends on the number of cars in the outfit, the total time of transport service, taking into account the increase in time for handling, the initial cost of the car and the cost of car maintenance and depreciation, as well as the mass of the freight and the coefficient of reliability of transport .
Taking into account the three components, mathematical expressions were obtained, which allow to perform mathematical modeling of the total costs for urban freight and by calculation to obtain the optimal mass of freight, which is transported depending on the coefficients of use of mileage and the coefficients of load capacity of the car.
Presented change depending optimal weight of cargo on changes greatness us coefficients and coefficients using run-duty vehicle use. It is shown that when the coefficient of use of the mileage is 0.5 and the value of the coefficient of load capacity of the car is 0.5, the planned mass of cargo for transportation is almost indistinguishable from the optimal one. When these coefficients are increased to one, the optimal mass increases 1.4-1.6 times. It is noted that such conclusions are characteristic of routes with different lengths.
It is shown that in order to reduce the total specific costs of urban freight traffic, it is necessary to carry out an adjustment by weight of the transported cargo by calculation . The initial data are the specified distance of carriage, as well as the specified values of the coefficients of use of the mileage and the coefficients of the load capacity of the car.