A fault diagnostics system of three-phase induction motors was implemented. The implemented system was based on acoustic signals of three-phase induction motors. A feature extraction step was performed using SMOFS-20-EXPANDED (shortened method of frequencies selection-20-Expanded). A classification step was performed using 3 classifiers: LDA (Linear Discriminant Analysis), NBC (Naive Bayes Classifier), CT (Classification Tree). An analysis was carried out for incipient states of three-phase induction motors measured under laboratory conditions. The author measured and analysed the following states of motors: healthy motor, motor with one faulty rotor bar, motor with two faulty rotor bars, motor with faulty ring of squirrel-cage. Measured and analysed states were caused by natural degradation of parts of the machine. The efficiency of recognition of the analysed states was good. The proposed method of fault diagnostics can find application in protection of three-phase induction motors.
In humans, iron deficiency represents a relevant occurrence in heart failure (HF), with or without anaemia, and is associated with the worst outcome. Moreover, chronic kidney disease (CKD) is a well-known comorbidity of HF and is strongly associated with the risk of developing anaemia. The most common cause of HF in dogs is myxomatous mitral valve disease (MMVD). To the best of our knowledge, no studies have examined the iron status in dogs with HF, with and without CKD. The aim of this retrospective study was to evaluate the iron status in dogs affected by MMVD and how strong is the relation with HF.
The retrospective study included 54 dogs with complete case records, echocardiography and laboratory analyses. Iron status was evaluated by measuring serum iron concentration (SIC), un- saturated iron binding capacity (UIBC), total iron binding capacity (TIBC), and percentage of saturation (%SAT).
The prevalence of dogs showing low serum iron concentration (SIC) was 18% in the whole population, 33% in symptomatic patients, 100% in dogs with acute decompensated HF. No signif- icant differences in SIC, UIBC, TIBC and %SAT median values were found among dogs classi- fied in different ACVIM (American College of Veterinary Internal Medicine) classes, between symptomatic and non-symptomatic patients, and among IRIS (International Renal Interest Soci- ety) classes. Azotemic and non-azotemic patients presented a significant difference in SIC mean values (p=0.02). Generalised linear model (GLM) revealed that dogs with low SIC were at high- er risk of being included in a higher ACVIM class (OR=6.383, p-value=0.014).
Log-rank analysis showed shorter survival in dogs with low SIC (p=0.020), multivariate Cox analysis revealed that only HF symptoms can affect survival.