We examined, noninvasively, the response of the left ventricular (LV) wall to precordially applied vibration in seven normal subjects. The LV posterobasal wall vibration was detected by an esophageal vibration sensor. Even though the amplitude of input vibration was maintained at a constant level, a sharp change in amplitude of the LV wall vibration was observed during the cardiac cycle, especi...

Misfire in an Internal Combustion engine is a serious problem that needs to be addressed to prevent engine power loss, fuel wastage and emissions. The vibration signal contains the vibration signature due to misfire and a combination of all vibration emissions of various engine components. The vibration signals acquired from the engine block are used here. Descriptive statistical features are u...

The information extraction capability of two widely used signal processing tools, Hilbert Transform (HT) and Wavelet Transform (WT), is investigated to develop a multi-class fault diagnosis scheme for induction motor using radial vibration signals. The vibration signals are associated with unique predominant frequency components and instantaneous amplitudes depending on the motor condition. Usi...

A real time on-line transformer vibration monitoring system based on the Labview is proposed and applied in the monitoring of abnormal vibration of transformer caused by DC bias in this paper. The monitoring of the transformer body vibration and the signal online analysis can be well performed by this system. The vibration signals of the transformer body are detected by three acceleration senso...

Under a contamination of background sound noises, it seems difficult especially in a real working situation to evaluate various type statistics of only an objective sound signal fluctuation. In many cases of the noise evaluation, some signal processing method have been employed to eliminate the effect of background sound noises by first measuring emitted sound levels. In this study, a new evalu...

The periodical transient impulses caused by localized faults are sensitive and important characteristic information for rotating machinery fault diagnosis. However, it is very difficult to accurately extract transient impulses at the incipient fault stage because the fault impulse features are rather weak and always corrupted by heavy background noise. In this paper, a new transient impulse ext...

As one of the most common gear failure modes, tooth wear can produce nonlinear modulation sidebands in the vibration frequency spectrum. However, limited research has been reported in monitoring the gear wear based on vibration due to the lack of tools which can effectively extract the small sidebands. In order to accurately monitor gear wear progression in a timely fashion, this paper presents...

Abstract: A novel bearing vibration signal fault feature extraction and recognition method based on the improved local mean decomposition (LMD), permutation entropy (PE) and the optimized K-means clustering algorithm is put forward in this paper. The improved LMD is proposed based on the self-similarity of roller bearing vibration signal extending the right and left side of the original signal ...

In machining industries, achieving better surface finish of a product is very essential. Surface finish is important in terms of tolerances, it reduces assembly time in mating surfaces which results in overall cost reduction. In this work, three cutting speeds, three feed rates and three depth of cuts were used in boring operation. During the boring operation, the accelerometer was fixed on the...