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Development of a Rigid One-Meter-Side and Cooled Coil Sensor at 77 K for Magnetic Resonance Sounding to Detect Subsurface Water Sources

Jun Lin, Guanfeng Du, Jian Zhang, Xiaofeng Yi, Chuandong Jiang, Tingting Lin
2017 Sensors  
The coil sensor has a rigid structure and square size of 1 m for deploying in a narrow underground space and is cooled at a low temperature of 77 K for improving the SNR.  ...  Magnetic resonance sounding (MRS) using the Earth's magnetic field is a noninvasive and on-site geophysical technique providing quantitative characteristics of aquifers in the subsurface.  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/s17061362 pmid:28604621 pmcid:PMC5492693 fatcat:uogjxukrdbbydhvwnxf3ybt56u

Hungarian national report on IAGA 2007–2010

L. Szarka, G. Sátori
2011 Acta Geodaetica et Geophysica Hungarica  
Recently started new topics based on the new datasets: dynamics of flux emergence and decay, fragmentation of active region magnetic fields, active region tilts, build-up of unstable magnetic configurations  ...  in the north-south phase lags of the solar cycles, connections between sunspot distributions and torsional belts, forecasts for the maximum of cycle 24, solar rotation, methodological problems of sunspot  ...  For this sensor ELGI designed and produced a spherical coil system which has a diameter of 20 cm. By using this coil system we developed a small size and user-friendly suspended magnetometer.  ... 
doi:10.1556/ageod.46.2011.2.4 fatcat:yfn2bxfphbhe5ogowkg5wu43ha

Conceptual design and multidisciplinary optimization of in-plane morphing wing structures

Daisaku Inoyama, Brian P. Sanders, James J. Joo, Douglas K. Lindner
2006 Smart Structures and Materials 2006: Modeling, Signal Processing, and Control  
The novel FBG-based crack sensor ( also named large FBG strain sensor) can detect 100000 at maximum, almost 20mm crack at the calibration length of 20 centimeter, and the accuracy can reach 0.002mm.  ...  In this paper, new technique of sensitivity-decreasing of FBG strain sensor has been brought forward and a new kind of FBG-based crack sensor is developed.  ...  (South Korea) If we consider the transmission of sound through a partition, we can actually measure the sound energy on both the source side and the receiving side to determine exactly what fraction of  ... 
doi:10.1117/12.658686 fatcat:rqnvt2atkjgnvpog5pivwjejzm

Discrimination of short speech‐like formant transitions

Astrid van Wieringen, Louis C. W. Pols
1992 Journal of the Acoustical Society of America  
-/•m sheet, annealed at 130øC, and slow cooled.  ...  A wall-mounted toroid can be formed by using two FOD sensors at right angles to each other and with the axis of each sensor at 45' to the reflecting surface.  ...  Here, the method is extended to include the response of broadband, transient sound sources and sources at several water depths.  ... 
doi:10.1121/1.405128 fatcat:dbtewzqvijhkta6op7ul3ribti

Duration modeling with hidden Markov models

L. F. M. ten Bosch, X. Wang, L. C. W. Pols
1993 Journal of the Acoustical Society of America  
The magnetic resonance imaging (MRI) technique was used to measure the three-dimensional structure of the vocal tract. The area function of the nasal tract was calculated from seven subjects at rest.  ...  The hypothesis of this paper is that monitoring the ambient noise under the ice, for which there is well-developed and reliable technology, may be an excellent way to detect a climate change signal.  ...  To achieve this, a "composite source signal" was developed. The signal consists of a voiced sound on 50 ms at the initial phase.  ... 
doi:10.1121/1.407916 fatcat:6oae5i4nxva63mnleko5dr3acm

Treatment of early and late reflections in a hybrid computer model for room acoustics

Graham Naylor
1992 Journal of the Acoustical Society of America  
-/•m sheet, annealed at 130øC, and slow cooled.  ...  A wall-mounted toroid can be formed by using two FOD sensors at right angles to each other and with the axis of each sensor at 45' to the reflecting surface.  ...  Aa goes to zero at T c and at T=0, going through a maximum at •55 K. Measurements have been done for various orientations of the magnetic field.  ... 
doi:10.1121/1.404930 fatcat:xeehcxepjvhuzmnaeudpqxtnvu

Predicting room acoustical behavior with the ODEON computer model

Graham Naylor, Jens Holger Rindel
1992 Journal of the Acoustical Society of America  
-/•m sheet, annealed at 130øC, and slow cooled.  ...  A wall-mounted toroid can be formed by using two FOD sensors at right angles to each other and with the axis of each sensor at 45' to the reflecting surface.  ...  Aa goes to zero at T c and at T=0, going through a maximum at •55 K. Measurements have been done for various orientations of the magnetic field.  ... 
doi:10.1121/1.404931 fatcat:z4hbezklfzgu7hyy7qvos3wyo4

Modeling and experiments with low‐frequency pressure wave propagation in liquid‐filled, flexible tubes

Cato Bjelland, Leif Bjo/rno/
1992 Journal of the Acoustical Society of America  
-/•m sheet, annealed at 130øC, and slow cooled.  ...  A wall-mounted toroid can be formed by using two FOD sensors at right angles to each other and with the axis of each sensor at 45' to the reflecting surface.  ...  Aa goes to zero at T c and at T=0, going through a maximum at •55 K. Measurements have been done for various orientations of the magnetic field.  ... 
doi:10.1121/1.404777 fatcat:xhmwz65h5bbqxbt52khae2rq7q

Underwater noise due to precipitation

Lawrence A. Crum, Hugh C. Pumphrey, Andrea Prosperetti, Leif Bjorno
1989 Journal of the Acoustical Society of America  
Sound propagation is the preeminent technique for sensing, identifying, and communicating under the ocean surface.  ...  However, the extraordinary spatial and temporal variability of the ocean has frustrated underwater acousticians for decades.  ...  Current matched-field research at NORDA is centered on techniques that attempt to match measured and predicted modal amplitudes for improved detection and localization of acoustic sources in shallow-water  ... 
doi:10.1121/1.2026824 fatcat:xbwjl6wggjh5xee7ci2vcphfd4

T.I.P.O. (Tesla Interferometric Planetary Observer) [article]

Adrian Sabin Popescu
2009 arXiv   pre-print
The presented T.I.P.O. mission is a proposal for a research program dedicated to study, by space borne interferometric methods, the radio emissions generated in the atmospheres and magnetospheres of planets  ...  In the last years the Space Science community was confronted to a continuous increasing interest in Martian missions, extra-solar planet search and multi-satellite missions.  ...  For the other problem of this antenna a High-Tc SQUIDs that use the superconductor YBCO (ibco) have been developed that are cooled at 77 to 90 K by liquid nitrogen, which has a lower cost than the "basic  ... 
arXiv:0902.3902v1 fatcat:sgdvwxxy7rbsfn6frgm42eoop4

Ray tracing in a turbulent, shallow‐water channel

Christian Bjerrum‐Niese, René Lützen, Leif Bjo/rno/
1998 Journal of the Acoustical Society of America  
Before and after exposure, magnetic resonance FISP 3-D angiograms ͑MRA͒ with submillimeter spatial resolution were acquired using a Siemens Vision MR System ͑1.5T͒ and extremity coil.  ...  One of the most promising methods is the use of magnetic resonance imaging ͑MRI͒ to detect the temperature elevation. In this paper the calibration and accuracy of MRI thermometry will be presented.  ...  The procedure requires the generation of a low-order shallow-water mode by the source array and the extraction from the received echo at the receiver array of a low-order shallow-water mode.  ... 
doi:10.1121/1.422455 fatcat:vqypn7trzberzap3bkznkoddcu

Scattering by two spheres: Theory and experiment

Irina Bjo/rno/, Leif Bjo/rno/
1998 Journal of the Acoustical Society of America  
Before and after exposure, magnetic resonance FISP 3-D angiograms ͑MRA͒ with submillimeter spatial resolution were acquired using a Siemens Vision MR System ͑1.5T͒ and extremity coil.  ...  One of the most promising methods is the use of magnetic resonance imaging ͑MRI͒ to detect the temperature elevation. In this paper the calibration and accuracy of MRI thermometry will be presented.  ...  The procedure requires the generation of a low-order shallow-water mode by the source array and the extraction from the received echo at the receiver array of a low-order shallow-water mode.  ... 
doi:10.1121/1.421626 fatcat:qf2u35fztjfgtgredwhbg53zwm

Spherical near field acoustic holography with microphones on a rigid sphere

Finn Jacobsen, Jo/rgen Hald, Efrén Fernandez, Guillermo Moreno
2008 Journal of the Acoustical Society of America  
There is a strong correlation between the subjective impression of reverberance with EDT and T30 and musical clarity with C80; 2.  ...  The poor quality of clarity was assessed for churches with longest EDT for the performance of music involving polyphony.  ...  It was found that at kϭR"rϭ5.8 V1ϭV2, at kϾ5.8 V1ϾV2, and at kϽ5.8 V1 was less than V2.  ... 
doi:10.1121/1.2934035 fatcat:57w2rziyfvcmnnyzsxlgg43qxa

Measurement of total sound energy density in enclosures at low frequencies

Finn Jacobsen
2008 Journal of the Acoustical Society of America  
There is a strong correlation between the subjective impression of reverberance with EDT and T30 and musical clarity with C80; 2.  ...  The poor quality of clarity was assessed for churches with longest EDT for the performance of music involving polyphony.  ...  It was found that at kϭR"rϭ5.8 V1ϭV2, at kϾ5.8 V1ϾV2, and at kϽ5.8 V1 was less than V2.  ... 
doi:10.1121/1.2934233 fatcat:vuavezpbsnabxmhi4jlbvbwgly

Parameter survey of a rib stiffened wooden floor using sinus modes model

Lars‐Göran Sjökvist, Jonas Brunskog, Finn Jacobsen
2008 Journal of the Acoustical Society of America  
There is a strong correlation between the subjective impression of reverberance with EDT and T30 and musical clarity with C80; 2.  ...  The poor quality of clarity was assessed for churches with longest EDT for the performance of music involving polyphony.  ...  It was found that at kϭR"rϭ5.8 V1ϭV2, at kϾ5.8 V1ϾV2, and at kϽ5.8 V1 was less than V2.  ... 
doi:10.1121/1.2933934 fatcat:fmeouf2iynctnculdxzvoqb4iu
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