Methods of evaluating the stability of transportation and technological schemes in variable material flow conditions

The article deals with transport schemes of cargo delivery from manufacturer to consumer. They consist of linear or intersect logistic chains. It is shown that when the input tact of stream of this scheme is stationary then static delays of material flow are present there. There was given the dependence of the delay from tact of initial flow. It was found that the static minimum of time delay reaches the optimal mode of delivery schemes. The problem of evaluating difficulties of the most probable delay of dynamic material flow in straight-way transportation and technological schemes or those with branching logistics chains was partly solved. Delays of material flow in this case are caused by the changes of input flows parameters. Options of material flows are recorded as discrete relationships. It was used the method of finite difference equations to evaluate the stability of transport and technological schemes with external disturbances. The order of the equation depends on the structure of logistic chains of the transport and technological scheme. The equation can be reduced to a uniform appearance. Ones can concluded about the stability of transport and technological scheme to external disturbances with the roots of the characteristic equation. An example of a unstable linear circuits was given. The selection of parameters of logistic operations are not sufficient conditions for stability evaluation. According to given models the delivery schemes should have additional input supply flow regulation.