Abstract
One of the main problems of interval computations is, given a functionf(x 1, ...,x n ) andn intervals x1, ..., x n , to compute the range y=f(x1, ..., x n ). This problem is feasible for linear functionsf, but for generic polynomials, it is known to be computationally intractable. Because of that, traditional interval techniques usually compute theenclosure of y, i.e., an interval that contains y. The closer this enclosure to y, the better. It is desirable to describe cases in which we can compute theoptimal enclosure, i.e., the range itself.
In this paper, we describe a feasible algorithm for computing the optimal enclosure forfractionally linear functionsf. Applications of this result tointelligent control are described.
Abstract
Одна из основных задач интервальных вычислений формулируется следуюим образом: дана функцияf(x 1, ...,x n ) иn интервалов x1, ..., x n ; требуется вычислить множество значений y=f(x1, ..., x n ). Эта задача имеет смысл для линейных функцийf, однако известно, что для обобщенных многочленов она вычислительно неразрецима. Поэтому традиционные интервальные методы, как правило, вычисляютвклчеuе y, т.е. интервал, содержащий в себе y. Чем ближе это включение к y, тем лучще. Желательно найти случаи, в которых возможно вычислитьоnmuмлъое вклчеue, т.е. само множество значений.
В работе описан адгоритм, лопускающий практическую реализацию, для вычисления оптимального включениябробно-лцных функцийf. Описаны приложения этого результата в областннмеллекмуалъно¶rt; управленцн.
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R. N. Lea, V. Kreinovich, R. Trejo, 1996
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Lea, R.N., Kreinovich, V. & Trejo, R. Optimal interval enclosures for fractionally-linear functions, and their application to intelligent control. Reliable Comput 2, 265–285 (1996). https://doi.org/10.1007/BF02391700
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DOI: https://doi.org/10.1007/BF02391700