Monitoring of Shallow-Grooved Tramway Crossings

Comparative Analysis of Helically Grooved and Circumferentially Grooved Labyrinth Seal

Labyrinth seals are used in turbo-machinery for reducing the leakage of working fluid. The energy lost by the fluid passing through the gap between labyrinth seal and rotor causes the reduction in leakage rate. But the fluid in between the labyrinth seal and rotor induce various forces (radial and tangential forces). These forces can be represented by certain numbers of coefficients, such as st...

New methods for the condition monitoring of level crossings

Probabilistic classifiers and time-scale representations: application to the monitoring of a tramway guiding system

We discuss a new diagnosis system combining wavelet analysis techniques and probabilistic classifiers for detecting tramway rollers defects. A continuous wavelet transform is applied on the vibration signals measured by specific accelerometers located on the rail. A temporal segmentation of the signals is carried out in order to identify the contribution of each pair of rollers to the overall v...

Tramway Networks as Route Graphs

The purpose of this paper is threefold: (1) to show a methodology for introducing formality step-by-step, starting from a “light-weight” ontology, (2) to apply it to the generic Route Graph model, instantiated here to Tramway Networks, and (3) to demonstrate that separation of concerns into layers of abstraction and application of generic formal notions such as graph abstraction lead to a usefu...

Patterning flows using grooved surfaces.

Through a simple analytical description we quantify how pressure-driven flows over grooved surfaces develop transverse components, which, for shallow grooves, can be modeled with simple anisotropic effective boundary conditions. Helical recirculation results in channels or capillaries with grooved walls. An experimental validation of our model is presented. Our analysis provides a workable guid...