
As already mentioned several times, the models DP very flexible in terms of opportunities and analysis of sensitivity to variations in the initial data, and in terms of possible inclusion in various versions of the problem. For example, a similar model can be constructed for applications in which is reviewed annually for more than two management options (the "conservation", "replacement", "reconstruction" and so on). One can consider the problem in which the cost or profit depends not only on the age of the equipment, but also from one parameter, such as the time elapsed after reconditioning, etc.
Some of these types of problems are contained in the exercises for this chapter. Discussed in this section, and proposed as an exercise problem with two alternative management  "replacement" or "conservation"  and a "parameter of state  the" age "of equipment  are one of the few cases where the duration of the plan at any time to obtain a solution without using a computer. Of course, if these 'tasks had often, use a computer, of course, necessary.
Remark. ' If the cost function of liquidity and the initial value problem 2 are time t elapsed since the beginning of the maintenance period, and r is equal to k, then the system should be characterized by two parameters m and t.
Consider two cases.
1. Point g is on the x axis  in the (t, 0). Under the influence of IP management for the year she moved to the state at (t + 1, 0). The operating costs for the year amounted r0 (t). Described change of the system is denoted in Fig. 10 segment connecting the points (t, 0) and (m + 1, 0) over the interval write the related costs, in this case, r0 (t). State of the system in Fig. 10 shows the circles in which we will further put down cost, obtained under constrained optimization. 