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| Titel |
TDR-Lab V.1.0: New TDR software for water content and electrical conductivity measurements |
| VerfasserIn |
José Vicente, David Moret-Fernández, Borja Latorre, César González-Cebollada, Francisco Lera |
| Konferenz |
EGU General Assembly 2011
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 13 (2011) |
| Datensatznummer |
250045628
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| Zusammenfassung |
| Time Domain Reflectometry (TDR) is a useful technique that allows real time and
simultaneous estimation of the apparent permittivity (Éa), which is related to the volumetric
soil water content (θ), and the soil bulk electrical conductivity (Ïăa). These parameters are
typically calculated using specific TDR software by graphical analysis or numerical
modelling of the TDR waveforms. This work presents the TDR-Lab V.1.0 software that,
compatible with Tektronics 1502C, TDR-100 Campbell Sci. and TRASE Soil-moisture
Equipment Corp. cable testers, allows estimation of θ and Ïăa by using different TDR
waveform analysis. The software, which has a user friendly graphical interface, includes
scheduling automated readings and automated waveform analysis applications,
connection to multiplexors SDMX50 and datalogger CR1000 (Campbell Sci.) and two
different types of TDR probe geometries (coaxial and three-wire TDR probes). Four
different methods of TDR waveform analysis for water content estimation have
been included: (i) manual method, where the user fixes the first peak and second
reflection point of the TDR waveform, (ii) the graphical “tangent method”, useful
for fast and accurate TDR waveforms analysis of long TDR probes (i.e. probes
longer than 10 cm); (iii) the graphical method of the “maximums”, that analyses the
derivative of the TDR waveform and is appropriate for homogeneous media, and (iv)
a TDR signal numerical modelling method for homogeneous media, that allows
accurate estimations of water content using extremely short TDR probes (between
0.7 and 3 cm length). The new software also includes estimations of the soil bulk
electrical conductivity either by graphical or numerical analysis of the TDR signal. |
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