AbstractThe question of whether there exists an approximation procedure to compute the resonances of any Helmholtz resonator, regardless of its particular shape, is addressed. A positive answer is given, and it is shown that all that one has to assume is that the resonator chamber is bounded and that its boundary is $${{\mathcal {C}}}^2$$
C
2
. The proof is constructive, providing a universal algorithm which only needs to access the values of the characteristic function of the chamber at any requested point.
In this article reengineering of processes of classification of objects in neural intellectual information systems of city development in the conditions of multi criteria approach is considered. The universal algorithm of calculation of cumulative total opinion of experts of the city district on the basis of a median of Kemeni who allows to order in the most reliable and objective way clusters rankings in the complex multilevel structures representing objects of municipal economy is offered. For receiving reliable results of an indistinct clustering it is necessary to reproduce the specified algorithm repeatedly at a certain number of clusters for various initial indistinct splitting and to compare values of criterion function of indistinct splitting which were received, for the purpose of adoption of the final decision on a necessary indistinct clustering.
The article presents a universal algorithm for evaluating the efficiency of innovative-investment projects in the field of renewable energy. A comparative analysis of methods for assessment the efficiency of implementation and development of renewable energy sources described in the research studies of the Russian and foreign authors is performed. The features and main indicators of such projects are noted. The most suitable methodology in terms of feasibility of involving renewable energy sources in a particular company, was identified for Russian realities.
Computing the Sound of the Sea in a Seashell