Aggregated evaluation of operation quality of complex hierarchical   network systems
  The main approaches for the formation of generalized conclusions about operation quality of complex hierarchical network systems are analized. Advantages and drawbacks of the "weakest" element method and a weighted linear aggregation method are determined. Nonlinear aggregation method is proposed for evaluating the quality of the systems, which consist of elements of the same priority. Hybrid approaches to form generalized conclusions are developed based on the main aggregation methods. It is shown that they allow to obtain more reliable aggregation results. 
Olexandr Polishchuk
cs.SY