Cable diagnosis is a crucial research topic for the reliability of embedded systems in automotive applications. This paper presents a methodology dedicated to the reflectometry analysis of branched networks in order to localize and characterize the faults which may affect it. The direct model (propagation along the cables) is modelled by a RLCG circuit model and the Finite Difference Time Domai...

Accurate moisture sensing is an important need for many research programs as well as in control of industrial processes. This paper describes the development of a high accuracy frequency domain sensing probe for use in obtaining dielectric measurements of materials suitable for work ranging from 300 MHz to 1 GHz. The probe was developed to accommodate a wide range of permittivity’s ranging from...

An assessment of time-domain reflectometry (TDR) for measuring the characteristic impedance ZTL of transmission lines is performed. The assessment includes the accuracy of measuring ZTL as a function of TDR electrical impedance Zo, the ability to measure impedance perturbations as a function of ZTL and Zo, and the ability to differentiate between transmission lines of similar ZTL. The informati...

This paper presents a model-based approach to determine dielectric constants from time domain reflectometry TDR measurement in highly conductive soils. It makes use of information contained in the TDR signal from the reflection at the surface of the soil rather than the reflection from the end of the probe. The TDR method is widely used to determine the volumetric water content of soils. Common...

We describe a demonstration system built upon Topic Detection and Tracking (TDT) technology. The demonstration system monitors a stream of news stories, organizes them into clusters that represent topics, presents the clusters to a user, and visually describes the changes that occur in those clusters over time. A user may also mark certain clusters as interesting, so that they can be “tracked” ...

This paper proposes sensors based on the time-domain reflectometry (TDR) technique for qualifying ethanol fuel. Four different probe geometries were proposed: bifilar, microstrip, coaxial, and helical. All probes allowed qualification of ethanol adulterated with water. Helical probe showed the best response. Thus, this proposal contributes to the development of electronic tongues.

Since 1990s, time domain reflectometry (TDR) has been applied to estimate the stem water content of living trees. Here, new calibration equations relating the apparent dielectric constant (Ka) to the volumetric water content (θ) were developed for two Mediterranean oak species. Our calibration equations differ from those previously calculated for other species, suggesting that stem water conten...

The knowledge of soil water content (SWC) dynamics in the upper soil layer is important for several hydrological processes. Due to the difficulty of assessing the spatial and temporal SWC dynamics in the field, some model-based approaches have been proposed during the last decade. The main objective of this work was to assess the performance of two approaches to estimate SWC in the upper soil l...