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...

− A measurement set-up is proposed to measure the oneport scattering parameter of a subscriber line at the Central Office. The measurements are performed in the time domain using periodic multi-sine signals. A pre-processing algorithm will deliver the impulse response of the one-port scattering parameter. It will de-noise and de-alias the impulse response and search for the first significant re...

In this study the focus is on ocean surface altimetry using the signals transmitted from GNSS (Global Navigation Satellite System) satellites. A low-altitude airborne experiment was recently conducted off the coast of Sydney. Both a LiDAR experiment and a GNSS reflectometry (GNSS-R) experiment were carried out in the same aircraft, at the same time, in the presence of strong wind and rather hig...

Accurate determination of spatial soil moisture distribution and monitoring its temporal variation have a significant impact on the outcomes of hydrologic, ecologic, and climatic models. Development of a successful remote sensing instrument for soil moisture relies on the accurate knowledge of the soil dielectric constant ( soil) to its moisture content. Two existing methods for measurement of ...

Quality of broadband connectivity over a residential power line is dependent on its topology; which is very different from twisted pair copper used in telephony. In this paper methods to estimate the topology of a power line are investigated. A two step procedure comprising of a set of correlation time domain Reflectometry (CTDR) measurements based on Single Ended Loop Testing (SELT) and an ini...

Remote sensing provides a capability to make frequent and spatially distributed measurements of surface soil moisture, whilst recent advances in affordable Time Domain Reflectometry probes allow continuous monitoring of profile soil moisture at specific points. We believe that reliable estimation of the spatial and temporal variation of profile soil moisture on a routine basis will require a co...

GPS multipath reflectometry (GPS-MR) is a technique that uses geodetic quality GPS receivers to estimate snow depth. The accuracy and precision of GPS-MR retrievals are evaluated at three different sites: grasslands, alpine, and forested. The assessment yields a correlation of 0.98 and an rms error of 6–8 cm for observed snow depths of up to 2.5 m. GPS-MR underestimates in situ snow depth by 10...

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...

4 Analysis of Small Angle Scattering Data 10 4.1 Model Independent Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4.1.1 The Scattering Invariant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4.1.2 Porod Scattering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 4.1.3 Guinier Analysis . . . . . . . . . . . . . . . . . . . . . ....

We present probabilistic models for use in detecting and tracking topics in broadcast news stories. Our information retrieval (IR) models are formally explained. The Topic Detection and Tracking (TDT) initiative is discussed. The application of probabilistic models to the topic detection and tracking tasks is developed, and enhancements are discussed. We discuss four variations of these models,...