The problem of optimally controlling a Wiener process until it leaves an interval (a; b) for the first time is considered in the case when the infinitesimal parameters of the process are random. When a = ��1, the exact optimal control is derived by solving the appropriate system of differential equations, whereas a very precise approximate solution in the form of a polynomial is obtained in the two-barrier case.
The dual core bit-byte CPU must be equipped with properly designed circuits, providing interface between the two processor units, and making it possible to exploit all its advantages like versatility of the byte unit and speed of the bit unit. First of all, the interface circuits should be designed in such a way, that they dont disturb maximally parallel operation of the units, and that the CPU as a whole works in the same manner as in a standard PLC. The paper presents hardware solutions supporting effective operation of PLC CPU-s. Possibilities of solving problems concerning data exchange between a CPU and peripheral circuits were presented, with a special stress on timers and counters, and also on data exchange between the bit unit and the byte unit. The objective of the proposed solutions is to decrease the time necessary for a CPU to access its peripheries.