Results 261 to 270 of about 23,458 (290)
Some of the next articles are maybe not open access.
Inclusion of hydrodynamic modulations to the improved electromagnetic bias theory
IGARSS 2000. IEEE 2000 International Geoscience and Remote Sensing Symposium. Taking the Pulse of the Planet: The Role of Remote Sensing in Managing the Environment. Proceedings (Cat. No.00CH37120), 2002The modulation of short ocean waves by longer ones is a likely contributor to the radar altimeter's electromagnetic ranging bias (EM-bias). An analytic model to account for this component of the EM bias is developed under a two-scale hydrodynamic assumption.
T. Elfouhaily +3 more
openaire +1 more source
Bias Noise Correction In Multifrequency Fixed Small Loop Electromagnetic System
21st EEGS Symposium on the Application of Geophysics to Engineering and Environmental Problems, 2008Recently, the use of fixed small loop electromagnetic surveys has become popular for environmental and engineering investigations of relatively shallow subsurfaces. The fixed small loop EM method is effective for the detection of anomalous zones by mapping and profiling of a large area.
Yuji Mitsuhata +2 more
openaire +1 more source
Electromagnetic bias of 10‐GHZ radar altimeter measurements of MSL
Marine Geodesy, 1984Electromagnetic bias, the small difference that exists between the radar measured mean sea level and the geometric mean sea level is an important issue in high precision satellite altimetry. Present day satellite altimetry has achieved, with SEASAT-1, a precision of 5 cm rms in the range measurement. Future altimeter designs are expected to improve the
L. W. Choy, D. L. Hammond, E. A. Uliana
openaire +1 more source
Nonlinear Modeling and Analysis of Electromagnetic Bearings With Permanent Magnets for Bias
Volume 1: 24th Conference on Mechanical Vibration and Noise, Parts A and B, 2012This article describes high fidelity modeling of electromagnetic (EM) bearings with permanent magnets (PM) used to supply bias current. We analyze both the PM and EM parts of the system. Magnetic circuit theory is first used to gain insight into the magnetic forces and allows for the dynamic analysis of a rigid rotor coupled with the magnetic bearings.
Peiman Naseradinmousavi +2 more
openaire +1 more source
Electromagnetic bias of 36‐GHZ radar altimeter measurements of MSL
Marine Geodesy, 1984The data reduction techniques used to determine the magnitude of electromagnetic (EM) bias in radar altimeter measurements of mean sea level (MSL) area described. Particular attention is given to the bias reduction scheme developed specifically for the Surface Contour Radar (SCR) instrument of the Ocean Topography Experiment (TOPEX).
Edward J. Walsh +3 more
openaire +1 more source
Observations on electromagnetic bias in radar altimeter sea surface measurements
Journal of Geophysical Research: Oceans, 1989Because the relative radar cross section of the sea surface increases below mean sea level and decreases above it, the range measurements of satellite radar altimeters are biased toward the wave troughs. Published and unpublished direct measurements of this electromagnetic (EM) bias are examined as well as the predictions of theoretical developments ...
Edward J. Walsh +3 more
openaire +1 more source
IEEE Transactions on Geoscience and Remote Sensing, 1993
Range measurements made by satellite radar altimeters experience an electromagnetic (EM) bias toward the troughs of ocean waves. Measurements taken with the NASA altimeter on the TOPEX/Poseidon satellite in a series of aircraft flights during the Surface Wave Dynamics Experiment (SWADE) indicate that EM bias is slightly higher at 5.3 GHz than at 13.6 ...
László Hévizi +6 more
openaire +1 more source
Range measurements made by satellite radar altimeters experience an electromagnetic (EM) bias toward the troughs of ocean waves. Measurements taken with the NASA altimeter on the TOPEX/Poseidon satellite in a series of aircraft flights during the Surface Wave Dynamics Experiment (SWADE) indicate that EM bias is slightly higher at 5.3 GHz than at 13.6 ...
László Hévizi +6 more
openaire +1 more source
A Ku-band altimeter for improved estimation of electromagnetic bias in radar altimetry
IEEE 1999 International Geoscience and Remote Sensing Symposium. IGARSS'99 (Cat. No.99CH36293), 2003A Ku-band altimeter has been designed and is currently being constructed. Tower and airplane measurements will be taken from the system. The data from this instrument will be used for improvement in electromagnetic (EM) bias estimation. This paper presents a description of the hardware for the altimeter and the experiment to be performed.
D.E. Crockett, D.V. Arnold, M.A. Jensen
openaire +1 more source
Magnetostriction electromagnetic–acoustic excitation of ultrasonic waves without a bias field
Russian Journal of Nondestructive Testing, 2016A high-performance technique is suggested for generating ultrasonic waves by the magnetic–acoustic method without using a bias field. The technique is based on the frequency doubling of emitted ultrasonic wave as compared to the frequency of the field coil of electromagnetic transducer due to the evenness of magnetostriction.
Yu. L. Gobov +2 more
openaire +1 more source
Actively bias-controlled metamaterial to mimic and modulate electromagnetically induced transparency
Applied Physics Letters, 2014We present an active microwave metamaterial composed of orthogonally arranged cut wires and positive-intrinsic-negative diodes, having capability of high-speed response. When a forward voltage is applied to turn the diodes on, analogue spectral response of a classical electromagnetically induced transparency is observed at 6.13 GHz for destructive ...
Dejia Meng +4 more
openaire +1 more source