Coda wave Interferometry (CWI)
Validation of a thermal bias control technique for Coda Wave Interferometry (CWI)
... The Coda Wave Interferometry (CWI) analysis serves to monitor the variation of propagation velocity in a heterogeneous medium with high precision (10 3 % in relative ...
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Study of stress-induced velocity variation in concrete under direct tensile force and monitoring of the damage level by using thermally-compensated Coda Wave Interferometry
... heterogeneity, Coda Wave Interferometry (CWI) shows great sensi- tivity to perturbations in concrete structures [4,5], which makes this method suitable for structural evaluation and ...
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Application of Ultrasonic Coda Wave Interferometry for Micro-cracks Monitoring in Woven Fabric Composites
... sonic wave is generated at one location on the specimen and recorded at another ...called coda wave interferometry (CWI) [ 10 ...term coda originates from musical science [ 11 ] and was ...
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Distributed fiber optics sensing and coda wave interferometry techniques for damage monitoring in concrete structures
... 3. Coda Wave Interferometry (CWI) Technique 3.1. Working Principle For SHM applications, the working frequency range for sonic methods or vibration measurement is normally below 10 kHz. As a result, ...
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Suivi du fluage par interférométrie de la CODA : illustration expérimentale lors d'un essai de flexion trois points
... ABSTRACT The use of CODA wave interferometry (CWI) is an emerging topic in civil engineering for the non destructive characterisation of concrete. The idea is to take benefit from the heterogeneity ...
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Small crack detection in cementitious materials using nonlinear coda wave modulation
... leakage. Coda Wave Interferometry (CWI), which relies on an analysis of the last part of the signal formed by multiple scattered waves, offers a sensitive method for detecting time-lapse ...
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Coda Wave Interferometry (CWI) for monitoring early-age cementitious mortar
... Yuxiang Zhang, Odile Abraham, Pierre Mounanga, Ali-Nordine Leklou, Vincent Tournat, Alain Le Duff, Bertrand Lascoup, Olivier Durandd. To cite this version:[r] ...
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Closed Crack Detection in Concrete with Coda Wave Non-Linear Modulation
... K EYWORDS : Coda Wave Interferometry, Concrete, Cracks, Health monitoring I NTRODUCTION Concrete is very sensitive to crack formation. Cracks are generally taken into consideration into design codes ...
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Detecting medium changes from coda by interferometry
... strong coda of multiply-scattered energy, and that this coda changes significantly, even in synthetic data, before and af- ter CO 2 ...this coda are promising for low-budget ...so-called coda ...
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Phase referencing in optical interferometry
... where PSF(x,y) is the instrumental point spread function, I true (x,y) is the true object brightness distribution, N(x,y) is the noise and the asterisk denotes convolution. In practice, interferometry does not ...
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Atmospheric propagation effects on radio interferometry
... We first show that systematic, elevation- angle dependent errors in estimates of baseline length using the Marini mapping func- tion are of order 5 cm for 8000-km bas[r] ...
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Characterizing exoplanets with infrared interferometry
... • Lot of expertise acquired from ground-based nulling interferometers (Mennesson et al. 2016) and VLTI (integrated optics, fringe tracking). • Next step, high-contrast interferometer on [r] ...
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Broadband nanosensing using heterodyne interferometry
... In general, scattered light from a bead in a rolling fringe pattern is a combination of fixed intensity signal (the DC component) and an oscillatory signal (the AC [r] ...
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Nonlinear effects for coda-type elastic waves in stressed granular media
... Short wave packets with a central frequency higher than the so-called cut-off frequency of the medium are emitted at one side of the statically stressed slab of glass beads and received at the other side after ...
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Simultaneous Temperature and Deformations Measurements Using Long-Wave Infrared Speckle Interferometry: A Novel Hybrid Technique for Industrial Nondestructive Testing
... ESPI in the Long Wave IR was demonstrated as a mean to record simultaneously the temperature variations and deformation. It can be used in defects detection where thermography and holography/shearography often ...
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Digital Holographic Interferometry in the Long-Wave Infrared Range for Measuring Large Deformations of Space Components under Thermal-Vacuum Testing
... 10. Georges, M.P.; Vandenrijt, J.-F.; Thizy, C.; Stockman, Y.; Queeckers, P.; Dubois, F.; Doyle, D. Digital Holographic Interferometry with CO 2 Laser Applied to Aspheric Space Reflector Testing. In Proceedings of ...
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Image Reconstruction in Optical Interferometry
... Optical Interferometry Optical multi-telescope interferometers provide sparse measurements of the Fourier transform ˆI λ (ν) of I λ (θ ), the specific brightness distribution of the observed object in angular ...
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Coherent control of neutron interferometry
... This phase turns out to be quite small and its effects are not observed in our measurements (the full derivation and small angle approximation are outlined in the[r] ...
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Coherent Interferometry Algorithms for Photoacoustic Imaging
... role and the absorbed energy density can be reconstructed from measurements of the pressure wave by inverting a spherical or a circular Radon transform [22, 23, 19, 20]. Recently, we have been interested in ...
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Speckle interferometry in the long-wave infrared for combining holography and thermography in a single sensor. Applications to nondestructive testing: the FANTOM project
... 6. CONCLUSIONS AND PERSPECTIVES In this paper, we have presented a new technique consisting of long wave infrared ESPI using CO 2 laser emitting at 10 µm and a microbolometer array camera sensitive in the 8-14 µm ...
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