Bibliographies thématiques / Correlated interferometry

Littérature scientifique sur le sujet « Correlated interferometry »

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Publié le 14 mars 2023

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Articles de revues sur le sujet "Correlated interferometry"

Yurke, B. « Interferometry with correlated fermions ». Physica B+C 151, n^o 1-2 (juillet 1988) : 286–90. http://dx.doi.org/10.1016/0378-4363(88)90179-9.

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Ayala-Garcia, Daniella, Andrew Curtis et Michal Branicki. « Seismic Interferometry from Correlated Noise Sources ». Remote Sensing 13, n^o 14 (9 juillet 2021) : 2703. http://dx.doi.org/10.3390/rs13142703.

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It is a well-established principle that cross-correlating seismic observations at different receiver locations can yield estimates of band-limited inter-receiver Green’s functions. This principle, known as Green’s function retrieval or seismic interferometry, is a powerful technique that can transform noise into signals which enable remote interrogation and imaging of the Earth’s subsurface. In practice it is often necessary and even desirable to rely on noise already present in the environment. Theory that underpins many applications of ambient noise interferometry assumes that the sources of noise are uncorrelated in time. However, many real-world noise sources such as trains, highway traffic and ocean waves are inherently correlated in space and time, in direct contradiction to the these theoretical foundations. Applying standard interferometric techniques to recordings from correlated energy sources makes the Green’s function liable to estimation errors that so far have not been fully accounted for theoretically nor in practice. We show that these errors are significant for common noise sources, always perturbing or entirely obscuring the phase one wishes to retrieve. Our analysis explains why stacking may reduce the phase errors, but also shows that in commonly encountered circumstances stacking will not remediate the problem. This analytical insight allowed us to develop a novel workflow that significantly mitigates effects arising from the use of correlated noise sources. Our methodology can be used in conjunction with already existing approaches, and improves results from both correlated and uncorrelated ambient noise. Hence, we expect it to be widely applicable in ambient noise studies.

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Pavičić, Mladen. « Spin-correlated interferometry with beam splitters : preselection of spin-correlated photons ». Journal of the Optical Society of America B 12, n^o 5 (1 mai 1995) : 821. http://dx.doi.org/10.1364/josab.12.000821.

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Paterova, Anna V., Dmitry A. Kalashnikov, Egor Khaidarov, Hongzhi Yang, Tobias W. W. Mass, Ramón Paniagua-Domínguez, Arseniy I. Kuznetsov et Leonid A. Krivitsky. « Non-linear interferometry with infrared metasurfaces ». Nanophotonics 10, n^o 6 (22 mars 2021) : 1775–84. http://dx.doi.org/10.1515/nanoph-2021-0011.

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Abstract The optical elements comprised of sub-diffractive light scatterers, or metasurfaces, hold a promise to reduce the footprint and unfold new functionalities of optical devices. A particular interest is focused on metasurfaces for manipulation of phase and amplitude of light beams. Characterisation of metasurfaces can be performed using interferometry, which, however, may be cumbersome, specifically in the infrared (IR) range. Here, we realise a new method for characterising metasurfaces operating in the telecom IR range using accessible components for visible light. Correlated IR and visible photons are launched into a non-linear interferometer so that the phase profile, imposed by the metasurface on the IR photons, modifies the interference at the visible photon wavelength. Furthermore, we show that this concept can be used for broadband manipulation of the intensity profile of a visible beam using a single IR metasurface. Our method unfolds the potential of quantum interferometry for the characterization of advanced optical elements.

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Zhang, Shane, Lili Feng et Michael H. Ritzwoller. « Three-station interferometry and tomography : coda versus direct waves ». Geophysical Journal International 221, n^o 1 (28 janvier 2020) : 521–41. http://dx.doi.org/10.1093/gji/ggaa046.

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SUMMARY Traditional two-station ambient noise interferometry estimates the Green’s function between a pair of synchronously deployed seismic stations. Three-station interferometry considers records observed three stations at a time, where two of the stations are considered receiver–stations and the third is a source–station. Cross-correlations between records at the source–station with each of the receiver–stations are correlated or convolved again to estimate the Green’s function between the receiver–stations, which may be deployed asynchronously. We use data from the EarthScope USArray in the western United States to compare Rayleigh wave dispersion obtained from two-station and three-station interferometry. Three three-station interferometric methods are distinguished by the data segment utilized (coda-wave or direct-wave) and whether the source–stations are constrained to lie in stationary phase zones approximately inline with the receiver–stations. The primary finding is that the three-station direct wave methods perform considerably better than the three-station coda-wave method and two-station ambient noise interferometry for obtaining surface wave dispersion measurements in terms of signal-to-noise ratio, bandwidth, and the number of measurements obtained, but possess small biases relative to two-station interferometry. We present a ray-theoretic correction method that largely removes the bias below 40 s period and reduces it at longer periods. Three-station direct-wave interferometry provides substantial value for imaging the crust and uppermost mantle, and its ability to bridge asynchronously deployed stations may impact the design of seismic networks in the future.

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Pavičić, Mladen, et Johann Summhammer. « Interferometry with Two Pairs of Spin Correlated Photons ». Physical Review Letters 73, n^o 24 (12 décembre 1994) : 3191–94. http://dx.doi.org/10.1103/physrevlett.73.3191.

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de Groot, Peter J. « Correlated errors in phase-shifting laser Fizeau interferometry ». Applied Optics 53, n^o 19 (30 juin 2014) : 4334. http://dx.doi.org/10.1364/ao.53.004334.

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Lam, M. M., et C. Dewdney. « Locality and nonlocality in correlated two-particle interferometry ». Physics Letters A 150, n^o 3-4 (novembre 1990) : 127–35. http://dx.doi.org/10.1016/0375-9601(90)90107-y.

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Su, Hang, Ruifang Ye, Fang Cheng, Changcai Cui et Qing Yu. « A Straightness Error Compensation System for Topography Measurement Based on Thin Film Interferometry ». Photonics 8, n^o 5 (30 avril 2021) : 149. http://dx.doi.org/10.3390/photonics8050149.

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Straightness error compensation is a critical process for high-accuracy topography measurement. In this paper, a straightness measurement system was presented based on the principle of fringe interferometry. This system consisted of a moving optical flat and a stationary prism placed close to each other. With a properly aligned incident light beam, the air wedge between the optical flat and the prism would generate the interferogram, which was captured by a digital camera. When the optical flat was moving with the motion stage, the variation in air wedge thickness due to the imperfect straightness of the guideway would lead to a phase shift of the interferogram. The phase shift could be calculated, and the air wedge thickness could be measured accordingly using the image processing algorithm developed in-house. This air wedge thickness was directly correlated with the straightness of the motion stage. A commercial confocal sensor was employed as the reference system. Experimental results showed that the repeatability of the proposed film interferometer represented by σ was within 25 nm. The measurement deviation between the film interferometer and the reference confocal sensor was within ±0.1 µm. Compared with other interferometric straightness measurement technologies, the presented methodology was featured by a simplified design and good environment robustness. The presented system could potentially be able to measure straightness in both linear and angular values, and the main focus was to analyze its linear value measurement capability.

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Csörgo, T. « Pion interferometry for strongly correlated spacetime and momentum space ». Nuclear Physics A 517, n^o 3-4 (29 octobre 1990) : 588–98. http://dx.doi.org/10.1016/0375-9474(90)90220-g.

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Thèses sur le sujet "Correlated interferometry"

Loh, Huanqian. « Applications of correlated photon pairs : sub-shot noise interferometry and entanglement ». Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/36126.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2006.
Includes bibliographical references (p. 89-95).
Using cesium atoms weakly coupled to a low-finesse cavity, we have generated photon pairs that are highly correlated in a non-classical way, as demonstrated by a large violation of the Cauchy-Schwartz inequality G = 760 +2100 -320 for a bin width T = 60 ns. Biphoton interferometry of the correlated pairs via the Holland-Burnett scheme holds promise to demonstrate precision beyond the shot noise limit, although the current interference fringe visibility of [beta]= 0.84 ± 0.04 only translates to a shot noise limited phase uncertainty. Polarization-time entangled pairs can also be directly generated, by optically pumping the atoms to both F = 3, mF = ±3 ground states. The degree of entanglement, expressed by the calculated fidelity f = 0.81 ± 0.09 and calculated Bell state parameter S = 2.3 ± 0.2, is estimated to be finite but not maximal.
by Huanqian Loh.
S.B.

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Ott, Christian [Verfasser], et Thomas [Akademischer Betreuer] Pfeifer. « Attosecond multidimensional interferometry of single and two correlated electrons in atoms / Christian Reinhold Ott ; Betreuer : Thomas Pfeifer ». Heidelberg : Universitätsbibliothek Heidelberg, 2012. http://d-nb.info/117978569X/34.

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Fuhrland, Matthias. « Konzeption und Umsetzung neuer Technologien zur biaxialen Winkelmessung und elektrooptischen Pseudostreckenmessung ». Doctoral thesis, München : Verl. der Bayerischen Akad. der Wiss, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1201784888043-41278.

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Amodjee, Ziyad. « Création et caractérisation de paires d'atomes corrélées : vers des tests de la mécanique quantique ». Thesis, université Paris-Saclay, 2020. https://pastel.archives-ouvertes.fr/tel-03141454.

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Des tests fondamentaux de la mécanique quantique tels que l'effet Hong-Ou-Mandel et la violation des inégalités de Bell ont été mis en évidence avec des photons dans les années 80. La violation des inégalités de Bell a d'abord été vérifiée avec des photons corrélés en spin, puis dans les années 90 avec des photons corrélés en impulsion via l'expérience de Rarity et Tapster. Notre équipe tente de transposer ces expériences d'optique au domaine des atomes froids. Cette thèse présente la mise en place du dispositif et la caractérisation du processus de création de paires d'atomes en vue d'un test de violation des inégalités de Bell avec des atomes corrélés en vitesse
Fundamental tests of quantum mechanics such as Hong-Ou-Mandel effect and Bell inequality violation has been experimentally demonstrated with photons in the 80s. Violation of Bell inequality was first verified wit spin correlated photons and then with momentum correlated photons in the 90s through the Rarity-Tapster experiment. In our team, we want to demonstrated those effects with cold atoms. This PhD thesis present the experimental setup and the characterization of the atomic creation process of momentum correlated atoms for a test of violation of Bell inequality

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FRANCESCHINI, PAOLO. « NOVEL SCHEMES FOR ULTRAFAST MANIPULATION OF QUANTUM MATERIALS ». Doctoral thesis, Università Cattolica del Sacro Cuore, 2022. http://hdl.handle.net/10280/111822.

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La possibilità di controllare le proprietà elettroniche on-demand su una scala di tempo ultraveloce rappresenta una delle sfide più intriganti verso la realizzazione di dispositivi fotonici ed elettronici di nuova generazione. Stimolata da questo, negli ultimi decenni la ricerca scientifica ha concentrato la propria attenzione su diverse piattaforme a stato solido. Tra tutte, nanostrutture dielettriche (e metamateriali) e materiali correlati si presentano come i più promettenti candidati per la realizzazione di dispositivi dotati di nuove funzionalità. Al di là delle caratteristiche specifiche che rendono i dielettrici più adatti ad applicazioni in fotonica e i materiali correlati ai dispositivi elettronici, entrambe le categorie manifestano nuove funzionalità se soggetti ad uno stimolo esterno sotto forma di impulsi di luce con durata più breve della scala di tempo caratteristica del rilassamento dei gradi di libertà interni al sistema. Infatti, lo stato fuori equilibrio raggiunto a seguito di una foto-eccitazione presenta proprietà elettroniche ed ottiche di gran lunga differenti da quelle all'equilibrio. Pertanto, l'obiettivo di questo lavoro di tesi consiste nello sviluppo di nuovi metodi ed approcci sperimentali in grado di indurre, misurare e controllare nuove funzionalità in materiali complessi su una scala di tempo ultraveloce.
The possibility to control the electronic properties on-demand on an ultrafast time scale represents one of the most exciting challenges towards the realization of new generation photonic and electronic devices. Triggered by this, in the last decades the research activity focused its attention to different solid-state platforms. Among all, dielectric nanostructures (and metamaterials) and correlated materials represent the most promising candidate for the implementation of devices endowed by new functionalities. Apart from the specific features making dielectrics more suitable for photonic applications and correlated materials for electronic devices, both categories exhibit new functionalities if subjected to an external stimulus in the form of excitation light pulses shorter than the relaxation timescale of the internal degrees of freedom of the system. Indeed, the out-of-equilibrium state achieved upon photoexcitation exhibits electronic and optical properties highly different from those at equilibrium. Therefore, the aim of this thesis work consists in the development of new methods and experimental approaches capable to induce, measure, and control new functionalities in complex materials on an ultrafast time scale.

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Fuhrland, Matthias. « Konzeption und Umsetzung neuer Technologien zur biaxialen Winkelmessung und elektrooptischen Pseudostreckenmessung ». Doctoral thesis, München Beck, 2007. http://d-nb.info/988973138/04.

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Holler, Christian Matthias. « Correlator and antenna design for the Arcminute Microkelvin Imager (AMI) ». Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.619994.

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Besser, Pimentel Felipe Ernesto. « Design and test of a digital correlator for the NIR heterodyne interferometer ». Tesis, Universidad de Chile, 2018. http://repositorio.uchile.cl/handle/2250/151763.

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Magíster en Ciencias de la Ingeniería, Mención Eléctrica
Este trabajo ha sido parcialmente financiado por CONICYT, a través de su fondo ALMA para el desarrollo de la astronomía, proyecto 31140025, QUIMAL, proyecto 1500010, y CATA-Basal PFB06
21/08/2020

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Foster, Griffin. « Large-N correlator systems for low frequency radio astronomy ». Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:2bca41ff-ec75-4a41-a634-c5bbbceae434.

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Low frequency radio astronomy has entered a second golden age driven by the development of a new class of large-N interferometric arrays. The low frequency array (LOFAR) and a number of redshifted HI Epoch of Reionization (EoR) arrays are currently undergoing commission and regularly observing. Future arrays of unprecedented sensitivity and resolutions at low frequencies, such as the square kilometer array (SKA) and the hydrogen epoch of reionization array (HERA), are in development. The combination of advancements in specialized field programmable gate array (FPGA) hardware for signal processing, computing and graphics processing unit (GPU) resources, and new imaging and calibration algorithms has opened up the oft underused radio band below 300 MHz. These interferometric arrays require efficient implementation of digital signal processing (DSP) hardware to compute the baseline correlations. FPGA technology provides an optimal platform to develop new correlators. The significant growth in data rates from these systems requires automated software to reduce the correlations in real time before storing the data products to disk. Low frequency, widefield observations introduce a number of unique calibration and imaging challenges. The efficient implementation of FX correlators using FPGA hardware is presented. Two correlators have been developed, one for the 32 element BEST-2 array at Medicina Observatory and the other for the 96 element LOFAR station at Chilbolton Observatory. In addition, calibration and imaging software has been developed for each system which makes use of the radio interferometry measurement equation (RIME) to derive calibrations. A process for generating sky maps from widefield LOFAR station observations is presented. Shapelets, a method of modelling extended structures such as resolved sources and beam patterns has been adapted for radio astronomy use to further improve system calibration. Scaling of computing technology allows for the development of larger correlator systems, which in turn allows for improvements in sensitivity and resolution. This requires new calibration techniques which account for a broad range of systematic effects. And, a deep integration between DSP hardware and software data reduction into a single backend.

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Hickish, Jack. « Digital signal processing methods for large-N, low-frequency radio telescopes ». Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:7d983fb3-9411-4906-92cd-70e2c1040b54.

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Current attempts to make precision measurements of the HI power spectrum at high redshifts have led to the construction of several low-frequency, large-N, interferometric arrays. The computational demands of digital correlators required by these arrays present a significant challenge. These demands stem from the treatment of radio telescopes as collections of two-element interferometers, which results in the need to multiply O(N²) pairs of antenna signals in an N-element array. Given the unparalleled flexibility offered by modern digital processing systems, it is apt to consider whether a different way of treating the signals from antennas in an array might be fruitful in current and future radio telescopes. Such methods potentially avoid the unfavourable N² scaling of computation rate with array size. In this thesis I examine the prospect of using direct-imaging methods to map the sky without first generating correlation matrices. These methods potentially provide great computational savings by creating images using efficient, FFT-based algorithms. This thesis details the design and deployment of such a system for the Basic Element of SKA Training II (BEST-2) array in Medicina, Italy. Here the 32-antenna BEST-2 array is used as a test bed for comparison of FX correlation and direct-imaging systems, and to provide a frontend for a real-time transient event detection pipeline. Even in the case of traditional O(N²) correlation methods, signal processing algorithms can be significantly optimized to deliver large performance gains. In this thesis I present a new mechanism for optimizing the cross-correlation operation on Field Programmable Gate Array (FPGA) hardware. This implementation is shown to achieve a 75% reduction in multiplier usage, and has a variety of benefits over existing optimization strategies. Finally, this thesis turns its focus towards The Square Kilometre Array (SKA). When constructed, the SKA will be the world's largest radio telescope and will comprise a variety of arrays targeting different observing frequencies and science goals. The low-frequency component of the SKA (SKA-low) will feature ~250,000 individual antennas, sub-divided into a number of stations. This thesis explores the impact of the station size on the computational requirements of SKA-low, investigating the optimal array configuration and signal processing realizations.

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Chapitres de livres sur le sujet "Correlated interferometry"

Silverman, Mark P. « Interferometry of Correlated Particles ». Dans More Than One Mystery, 59–99. New York, NY : Springer New York, 1995. http://dx.doi.org/10.1007/978-1-4612-2504-1_3.

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Gefen, Yuval. « Quantum Interferometry with Electrons : Outstanding Challenges ». Dans Strongly Correlated Fermions and Bosons in Low-Dimensional Disordered Systems, 13–41. Dordrecht : Springer Netherlands, 2002. http://dx.doi.org/10.1007/978-94-010-0530-2_2.

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Actes de conférences sur le sujet "Correlated interferometry"

Lucido, Mario, Federica Meglio, Vito Pascazio et Gilda Schirinzi. « Dual-baseline SAR interferometry from correlated phase signals ». Dans 2008 IEEE Radar Conference (RADAR). IEEE, 2008. http://dx.doi.org/10.1109/radar.2008.4721098.

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Villamizar-Morales, J., L. X. Bautista-Rozo et D. A. Rodriguez. « A computational signal processing system for correlated digital interferometry ». Dans 48th Midwest Symposium on Circuits and Systems, 2005. IEEE, 2005. http://dx.doi.org/10.1109/mwscas.2005.1594440.

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Fultz, Derek W., et Jeffrey S. Allen. « Non-Intrusive Pressure Measurement in Microchannels ». Dans ASME 2007 5th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2007. http://dx.doi.org/10.1115/icnmm2007-30215.

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Direct pressure and flow rate measurement in microsystems has been problematic due to micro and nano length scales. Commercially available pressure and flow rate transducers are typically orders of magnitude larger than the channel cross sections making these sensors impractical for microchannels. A novel, non-intrusive measurement technique has proven to be adaptable for making such measurements. The technique, based upon backscattering interferometry, correlates changes in interferometric fringe morphology to fluid compressibility. Sub-Pascal pressure detection has been demonstrated using an unfocused laser beam impinging on a fluid-filled, glass capillary tube. Fringe movement and thickness change, resulting from fluid velocity changes and transverse tube deflection, have been correlated to pressure values via the Hagen-Poiseuille relationships for laminar flow.

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Ebstein, Steven M., et David Korff. « FOCI : a generalization of intensity interferometry ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1988. http://dx.doi.org/10.1364/oam.1988.mx8.

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A generalization of intensity interferometry and imaging laser correlography (Hanbury Brown-Twiss effect) is described. The technique measures 〈l(x)A*(x + Δ + ϵ)A(x + Δ)〉, the correlation of the intensity at x with the field cross product at x + Δ over a distance ϵ. The result yields a term, μ*(Δ + ϵ)μ(Δ), analogous to the cross spectrum measured with the Knox-Thompson method for astronomical speckle imaging. The modulus and phase of the spatial coherence function can be recovered from this phase-difference-type term. The measurements involved do not require co-phasing over the large distance Δ. A light bucket measures l(x), and an interferometer with aperture ϵ (a lens is sufficient) measures A*(x + Δ + ϵ)A(x +Δ). The two measurements are numerically correlated. The results of a demonstration experiment that shows that the technique recovers modulus and phase information are presented.

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Idell, Paul S., John D. Gonglewski, David G. Voelz, B. Martin Levine et Brian Spielbusch. « Experimental investigation of the effects of atmospheric scintillation on image synthesis with intensity interferometer data ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1988. http://dx.doi.org/10.1364/oam.1988.wl1.

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Since the average brightness distribution of astronomical objects and the mutual intensity (complex coherence function) of the observed field are related by a Fourier transform, it is possible to synthesize images from far-field correlation measurements. Owing to the fact that detected intensities (rather than complex fields) are correlated at the receiver, intensity interferometry is an approach to measuring such correlations, which is largely insensitive to the effects of the earth’s atmosphere. We investigate the effect that atmosphere-induced fluctuations in the detected field amplitude (i.e., atmospheric scintillation) have on one’s ability to recover imagery using intensity interferometer data. To model the effects of the atmosphere on two-point intensity correlation measurements, we have adopted the theory of Beran and Whitman1 which provides expressions for the scintillation covariance function (in the case of isoplanaticity) and a first-order isoplanatic correction. We report on our attempt to verify these relations in a laboratory setting using Gaussian phase screens of known statistics2 and an image recovery methodology known as imaging correlography.3 We also investigate the performance of postdetection processing schemes applied to compensate for the effects of scintillation in the digitally recovered imagery.

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Geng, Phil, Robert R. Martinson, Richard L. Williams, Michael Mello et Steve Cho. « Shadow Moire´ Evaluation of Motherboard Warpage Under Preload CPU Thermal Solutions ». Dans ASME 2005 Pacific Rim Technical Conference and Exhibition on Integration and Packaging of MEMS, NEMS, and Electronic Systems collocated with the ASME 2005 Heat Transfer Summer Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/ipack2005-73046.

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This work investigated the motherboard coplanarity and preload correlation using the shadow moire´ interferometry. Motherboards under three different preloads in the CPU area were examined at room temperature and elevated temperature. Both the global board warpage and the local board warpage around the CPU area were measured for preload and temperature correlations. The measured board coplanarity was correlated to the board preload successfully. The results clearly identified a failure mode from the outlier, which has totally different warpage shape and corresponds to the uneven preload case. Also, the creep effect under preload during heating stage was observed and quantified.

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Marathay, A. S. « Phase function of spatial coherence via multiple intensity correlations ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1985. http://dx.doi.org/10.1364/oam.1985.tht3.

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The pioneering work of Hanbury Brown and Twiss on intensity interferometry1 was followed by that of Gamo2 who proposed a triple intensity correlator arrangement to derive the phase of the coherence function. This method met with limited success because the expression of intensity correlation with three collectors provides only one relation for the two unknowns, namely, the cosine and the sine of the phase argument. Consider the possibility of having a very large square array of mirrors (each mirror is of the intensity interferometer type to concentrate light onto a detector; not of imaging quality). It is possible to show that by using triple and quadruple intensity correlations the cosine and the sine of the phase argument of the spatial coherence function can be determined for all possible mirror separations in the array. This coupled with the usual intensity interferometry which measures the square of the absolute value of the coherence function will allow us to invert the Van Cittert-Zernike result to derive the intensity distribution across an astronomical object.

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Holley, Brian M., Sandor Becz et Lee S. Langston. « Measurement and Calculation of Turbine Cascade Endwall Pressure and Shear Stress ». Dans ASME Turbo Expo 2005 : Power for Land, Sea, and Air. ASMEDC, 2005. http://dx.doi.org/10.1115/gt2005-68256.

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The complex three-dimensional fluid flow on the endwall in an axial flow turbine blade or vane passage has been extensively investigated and reported on in turbomachinery literature. The aerodynamic loss producing mechanisms associated with the endwall flow are still not fully understood or quantitatively predictable. To better quantify wall friction contributions to endwall aerodynamic loss, low Mach number wind tunnel measurement of skin friction coefficients have been made on one endwall of a large scale cascade of high pressure turbine airfoils, at engine operating Reynolds numbers. Concurrently, predictive calculations of the endwall flow shear stress have been made using a computational fluid dynamics (CFD) code. Use of the oil film interferometry skin friction technique is described and applied to the endwall, to measure local skin friction coefficients and shear stress directions on the endwall. These are correlated with previously reported measured local endwall pressure gradients. The experimental results are discussed and compared to the CFD calculations, to answer questions concerning endwall aerodynamic loss predictive ability.

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Bourdarot, Guillaume, Jean-Philippe Berger, Hugues Guillet de Chatellus et Jean-Baptiste Le Bouquin. « MACH 2 : Mach-Zehnder analog correlator for heterodyne infrared interferometry ». Dans Optical and Infrared Interferometry and Imaging VII, sous la direction de Antoine Mérand, Stephanie Sallum et Peter G. Tuthill. SPIE, 2020. http://dx.doi.org/10.1117/12.2562059.

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Lecian, Orchidea Maria. « Gedanken Tests for Correlated Michelson Interferometers One-interferometer tests and two-interferometer tests : the role of cosmologically-implemented models including Poincare particles ». Dans 2018 2nd International Conference on Applied Mathematics, Modelling and Statistics Application (AMMSA 2018). Paris, France : Atlantis Press, 2018. http://dx.doi.org/10.2991/ammsa-18.2018.51.

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