Steam turbine stress control using NARX neural network

Considered here is concept of steam turbine stress control, which is based on Nonlinear AutoRegressive neural networks with eXogenous inputs. Using NARX neural networks,whichwere trained based on experimentally validated FE model allows to control stresses in protected thickwalled steam turbine element with FE model quality. Additionally NARX neural network, which were trained base on FE model, includes: nonlinearity of steam expansion in turbine steam path during transients, nonlinearity of heat exchange inside the turbine during transients and nonlinearity of material properties during transients. In this article NARX neural networks stress controls is shown as an example of HP rotor of 18K390 turbine. HP part thermodynamic model as well as heat exchange model in vicinity of HP rotor,whichwere used in FE model of the HP rotor and the HP rotor FE model itself were validated based on experimental data for real turbine transient events. In such a way it is ensured that NARX neural network behave as real HP rotor during steam turbine transient events

Badgers as a potential source of bovine tuberculosis – first studies in Poland

Since 2009, Poland has been recognized as a country officially free of bovine tuberculosis (BTB). However, new outbreaks are each year quoted. In many countries it has been shown that badgers ( Meles meles ) are a vector of Mycobacterium bovis/caprae ( M.bovis/caprae ) and a source of bovine tuberculosis for many domestical species, mainly for cattle. The aim of the presented study was to determine, for the first time in Poland, the occurrence of tuberculosis in badgers in areas where the disease occurs in cattle. Tissue samples were examined by classical microbiology methods, mycobacteria growth indicator tube (MGIT), and real time PCR. A total of 155 samples from 31 badgers were examined. In any case Mycobacterium bovis/caprae infection has not been diagnosed. This indicates that badgers probably are not a vector of bovine tuberculosis in Poland