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The appearance of repetitive transients in a vibration signal is one typical feature of faulty rolling element bearings. However, accurate extraction of these fault-related characteristic components has always been a challenging task, especially when there is interference from large amplitude impulsive noises. A frequency domain multipoint kurtosis (FDMK)-based fault diagnosis method is proposed in this paper. The multipoint kurtosis is redefined in the frequency domain and the computational accuracy is improved. An envelope autocorrelation function is also presented to estimate the fault characteristic frequency, which is used to set the frequency hunting zone of the FDMK. Then, the FDMK, instead of kurtosis, is utilized to generate a fast kurtogram and only the optimal band with maximum FDMK value is selected for envelope analysis. Negative interference from both large amplitude impulsive noise and shaft rotational speed related harmonic components are therefore greatly reduced. The analysis results of simulation and experimental data verify the capability and feasibility of this FDMK-based method

The aim of this study was to evaluate the initial results of 41 patients with Budd-Chiari syndrome (BCS) with inferior vena cava (IVC) thrombosis, with regard to the clinical safety and feasibility of the therapeutic approaches selected according to the classification of the condition. Forty-one patients with BCS and IVC thrombosis were admitted for retrospective analysis. All 41 patients were classified as having one of three types of BCS. Interventional therapy was used successfully in 28 patients (68.3%), 7 patients (17.1%) were given conservative treatment and 6 patients (14.6%) were treated with surgical shunts. The interventional approach was used in 29 patients in total and was successful in 28 patients (all those of types I and II, and 3 of the 4 patients of type III with acute thrombosis; 96.6%). None of these 28 patients had pulmonary embolism, pericardial tamponade or intra-abdominal bleeding. After 1–5 years, 4 patients (9.8%) had a second dilation of the IVC. In the 7 cases treated in a conservative manner, 2 cases succumbed to upper gastrointestinal bleeding and 1 case succumbed to liver and kidney failure. This study indicates that the classification of BCS patients with IVC thrombosis is helpful in selecting a therapeutic approach. Interventional therapy is the first therapeutic choice for BCS patients with IVC thrombosis of type I, type II or type III with acute thrombosis. For the patients of type III with an obsolete thrombus, surgical shunts or conservative treatment are the main therapeutic methods.