Polymorphonuclear leukocyte (PMN) recruitment to sites of inflammation is initiated by selectin-mediated PMN tethering and rolling on activated endothelium under flow. Cell rolling is modulated by bulk cell deformation (mesoscale), microvillus deformability (microscale), and receptor-ligand binding kinetics (nanoscale). Selectin-ligand bonds exhibit a catch-slip bond behavior, and their dissoci...

In this paper the wavelet packet transform is used for processing of rolling element bearing fault signals. The effectiveness of the envelope analysis technique is combined with the flexibility of the wavelet packet transform, helping in the minimization of interventions by the end user. According to the proposed method, a time-frequency decomposition of a vibration signal is provided and the c...

Envelope Detection (ED) is traditionally always used with Fast Fourier Transform (FFT) to identify the rolling element bearing faults. The inability of FFT to detect non-stationary signals makes Wavelet Analysis (WA) an alternative for machinery fault diagnosis as WA can detect both stationary and non-stationery signals. A comparative study of ED with FFT and WA techniques for bearing fault dia...

Elastohydrodynamically lubricated (EHL) contacts are fundamental for several rotating machine elements. For example gears, rolling element bearings and lubricated chain drives work due to the principle of EHL. All of these machine elements require maintenance and, as condition based maintenance has increased in industry, the need for monitoring techniques has also increased. In order to avoid i...

Tlre preserrce oflrarrl corrtarnir~rrrIt.s in lubricated rolling bearing.~ is (I rrrrijor cr1~1.s~ of /~rel~rrrti~re failure, for exarnple by fatigue or I J ~ rrbr(r.sive rt~erlr of rolling el en rent.^, races or cages. However; tlre brtrotluctiorr of rtruclr Irorcler ceranzic (u.sually silicon nitride) balls or r01ler.s rurrrrirrg rlgnirzst steel races, in tlre lzybrid bearing concept, is like...

The vibration signal is nonstationary and it is difficult to acquire the sample with typical fault. An improved ACO algorithm based on adaptive control parameters is introduced into SVM model to propose a new fault diagnosis (IMASFD) method in this paper. In the IMASFD method, the EMD method is used to decompose fault vibration signal into IMF components, the energy of IMF components is selecte...

Rolling bearings are key components of rotary machines. To ensure early effective fault diagnosis for bearings, a new rolling bearing fault diagnosis method based on variational mode decomposition (VMD) and an improved kernel extreme learning machine (KELM) is proposed in this paper. A fault signal is decomposed via VMD to obtain the intrinsic mode function (IMF) components, and the approximate...

This paper presents a signal analysis technique for machine health monitoring based on the Hilbert-Huang Transform (HHT). The HHT represents a time-dependent series in a two-dimensional (2-D) time-frequency domain by extracting instantaneous frequency components within the signal through an Empirical Mode Decomposition (EMD) process. The analytical background of the HHT is introduced, based on ...

In this work1 we introduce a complementaritybased rolling friction model to characterize dissipative phenomena at the interface between moving parts. Since the formulation is based on differential inclusions, the model fits well in the context of nonsmooth dynamics, and it does not require short integration timesteps. The method encompasses a rolling resistance limit for static cases, similar t...