Hand-foot-mouth disease (HFMD) is a common infectious disease caused by a group of enteroviruses, with enterovirus 71 (EV-71) and Coxsackie virus A16 (CA-V16) being the most prevalent in China 1, 2 . Over the last decade, outbreaks of HFMD that were associated with EV71 have been reported in countries in the Western Pacific Region, including Japan, Malaysia, Singapore, and China 3, 4 . The cumulative total of the reported cases in China has reached approximately 1.7 million, 1.9 million, and 2.7 million in 2010, 2013, and 2014, respectively 5, 6 . The clinical manifestations of most HFMD cases were mild and limited to fever, rash, or herpes on hand, foot, and mouth 7 . In general, mild infections are self-limited and not life-threatening, while severe HFMD are often associated with neurological and systemic complications, such as aseptic meningitis, brainstem encephalitis, acute flaccid paralysis, myocarditis and pulmonary oedema that requires hospitalization, or even causing death 2, 8 . Unfortunately, the incidence of severe HFMD in mainland China is high.Evidences from global reports on HFMD epidemics have substantiated that the incidence of severe HFMD is elevating gradually, along with mortality rate 9 . Thus, identifying potential early indicators for severe HFMD is essential, which enable early medical interventions and alleviating the disease severity, subsequently reducing the mortality rate. Previous studies have found that the following conditions or practices were associated with the increased risk of severe HFMD: a duration of fever ≥3 days, body temperature ≥37.5 °C, fatigue, the use of glucocorticoids, the use of dehydrant drugs, maculopapular rash, hyperglycemia, vomiting, EV71 infection, attending home care, neutrophilia, and young age [10][11][12][13][14][15][16][17][18] . Although specific clinical manifestations have been identified using the Magnetic Resonance Imaging (MRI), the potential indicators of the disease severity were not validated.

In order to solve the problem of pitting corrosion discrimination of rolling element bearing on vibrating screen. We established the vibrating model of pitting corrosion of rolling element bearing inner and outer rings faults on vibrating screen based on rotating machinery rolling element bearings operating mechanism and Hertz contact theory. We simulate this model and analyze the results. The results show that, when the outer ring of the rolling element bearing of vibrating screen has multi-point pitting corrosion, there is an apparent modulation phenomenon at the response amplitude. When the inner ring of the rolling element bearing of vibrating screen has multi-point pitting corrosion, there is a slight modulation phenomenon at the response amplitude.

Aiming at the discrimination problem of the multi-point pitting corrosion fault for the vibrating machine rolling bearing, the vibration model of the multi-point pitting corrosion fault was built for the vibrating machine rolling bearing with inner ring and outer ring based on Hertz contact theory and the discrimination criterion of the multi-point pitting corrosion fault was proposed. At the same time, the theoretical model was simulated and the experiment was finished in the vibrating sieve. The experiment results are consistent with the theoretical analysis results. The results show that there is the obvious difference from the fault characteristic spectrum of the rolling bearing multi-point pitting corrosion for the vibrating machine and the rotating machinery. There is an obvious amplitude modulation phenomenon for the outer ring pitting corrosion fault of the vibrating machine rolling bearing, but there is not the amplitude modulation phenomenon for the outer ring pitting corrosion fault of the ideal rotating machinery rolling bearing. There is a slight amplitude modulation phenomenon for the inner ring pitting corrosion fault of the vibrating machine rolling bearing and but there is the obvious amplitude modulation phenomenon for the inner ring pitting corrosion fault of the ideal rotating machinery rolling bearing.