Results 121 to 130 of about 603 (176)
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Analysis of Eccentered Dipole Antenna for Borehole Radar
IEEE Transactions on Geoscience and Remote Sensing, 2009A dipole antenna in a borehole may be placed away from the center of the borehole, and this eccentricity produces additional complicated electromagnetic fields, which may influence borehole radar signals. In this paper, we analyze an eccentric dipole antenna in a borehole for borehole radars.
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Directional borehole radar calibration
Journal of Applied Geophysics, 2007We are developing an innovative low noise borehole radar system that is designed for a single borehole providing 3D imaging capabilities. Harsh and changing operating environments are challenges to the electronic design. Low noise systems are particularly sensitive to operating conditions. After a brief introduction, testing and calibration methods are
O. Borchert, M. Aliman, A. Glasmachers
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Singlehole borehole radar measurement with a thin directional borehole radar sonde
2013 7th International Workshop on Advanced Ground Penetrating Radar, 2013This study demonstrates 3-D imaging of a fault using a thin (5.4 cm diameter) directional borehole radar sonde. In order to make the thin sonde, we needed to reduce interference between the centered conducting cylinder (CCC) and the antenna elements in the coaxial-fed circular dipole array in a borehole (CFCAB). Ferrite beads were loaded in the CCC for
Satoshi Ebihara +3 more
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Polarimetric borehole radar and its applications
IEEE International Geoscience and Remote Sensing Symposium, 2003We introduce applications of radar polarimetry in borehole radar. One example is classification of subsurface fractures, where we estimate the water permeability of each fracture by radar polarimetry. Then polarimetric borehole radar was then used for cross-hole radar measurement.
Motoyuki Sato, Tomohiro Abe
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A borehole radar prototype: Development and testing
2012 14th International Conference on Ground Penetrating Radar (GPR), 2011A prototype of borehole radar has been successfully tested in three sites for different purposes under a field condition. The objective of the prototype is for providing an effective downhole tool for detecting targets in deep boreholes situated in a relatively high conductivity area such as the metal ores.
Sixin Liu +4 more
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Near Surface Applications Of Borehole Radar
9th EEGS Symposium on the Application of Geophysics to Engineering and Environmental Problems, 1996Borehole radar (BHR) measurements, collected adjacent to a landfill site, demonstrate the useful application of this technique in understanding the near surface (upper 30m) hydrogeological conditions. The stratigraphy consists of relatively uniform ice-contact sand deposits, with the water table at a depth of 16.5 m.
E. W. Gilson +3 more
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Analysis of Dipole Antenna Eccentered in a Borehole for Borehole Radar
2007 4th International Workshop on, Advanced Ground Penetrating Radar, 2007In this paper, we analyze response of borehole radar that use an electrically small dipole antenna in an eccentric borehole. Our approach is an extended version of the pseudoanalytic formulation, which was previously applied for analysis of an induction logging tool. In order to verify the calculation method, we did two experiments.
S. Ebihara, Y. Inoue
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A Directional Borehole Radar System
Subsurface Sensing Technologies and Applications, 2002In this paper we present the simulation and design of a directional borehole radar. In addition we discuss an imaging method for the radar system. The antenna system contains an electric dipole which is in one direction shielded by a cylindrical perfectly conducting reflector.
Koen W.A. van Dongen +4 more
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Borehole Radar Modeling for Reservoir Monitoring Applications
72nd EAGE Conference and Exhibition incorporating SPE EUROPEC 2010, 2010The use of down-hole sensors and remotely controlled valves in wells provide enormous benefits to reservoir management and oil production. We suggest borehole radar measurements as a promising technique capable of monitoring the arrival of undesired fluids in the proximity of production wells. The high radar sensitivity to contrasts in fluid saturation
Miorali, M., Slob, E.C., Arts, R.J.
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54th EAEG Meeting, 1992
Directional borehole radars have good potential (or 3-D determination of water-filled fractures and geological boundaries. The choice of polarization of electromagnetic wave used for measurements are quite significant in designing radar systems. Circular polarization has advantages for Ground penetrating radars (GPR), because the reflection efficiency ...
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Directional borehole radars have good potential (or 3-D determination of water-filled fractures and geological boundaries. The choice of polarization of electromagnetic wave used for measurements are quite significant in designing radar systems. Circular polarization has advantages for Ground penetrating radars (GPR), because the reflection efficiency ...
openaire +1 more source