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A photoacoustic image reconstruction method for point source recovery
Photons Plus Ultrasound: Imaging and Sensing 2021, 2021In this paper, a novel Delay and Glow (DAG), back projection-based photoacoustic reconstruction, for point source recovery is presented. The projections of the absorber coefficients are delayed and weighed based on the transducer directivity sensitivity and matched with the other projections from other transducer elements leading to glow the point ...
Hamid Moradi Kashkouli +3 more
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A point source/point receiver method for ultrasonic testing
1993 Proceedings IEEE Ultrasonics Symposium, 1993Much of the theory and practice of ultrasonic testing involves the use of the plane wave approximation and of transducers large enough to generate planar wavefronts. Motivated in part by the emergence of engineering materials for which conventional techniques become impractical, the research reported here addresses the use of spherical waves generated ...
N.N. Hsu, C.H. Palmer, S.E. Fick
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Science of the Total Environment, 2019
Although buffer zones around aquatic areas are a useful method for controlling non-point source pollution and restoring natural ecosystem services, proper delineation methods for lakes remain poorly defined, restricting their protection and the rational ...
Chun-hua Li +5 more
semanticscholar +1 more source
Although buffer zones around aquatic areas are a useful method for controlling non-point source pollution and restoring natural ecosystem services, proper delineation methods for lakes remain poorly defined, restricting their protection and the rational ...
Chun-hua Li +5 more
semanticscholar +1 more source
TIR collimator designs based on point source and extended source methods
SPIE Proceedings, 2015TIR collimator are essential illumination components demanding high efficiency, accuracy, and uniformity. Various illumination design methods have been developed for different design domains, including tailoring method, design via optimization, mapping and feedback method, and the simultaneous multiple surface (SMS) method.
T. Talpur, A. Herkommer
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Modeling of ultrasonic fields by distributed point source method
, 2003T. Kundu +4 more
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Point Source Super-resolution Via Non-convex $$L_1$$ Based Methods
Journal of Scientific Computing, 2016In the super-resolution problem, one has to recover sparse signals \(x\in {\mathbb R}^N\) consisting only of separated peaks from frequency measurements up to a low frequency cutoff \(f_c\). Then \(\lambda_c = 1/f_c\) is called Rayleigh length of \(x\).
Yifei Lou, Penghang Yin, Jack Xin
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SLODAR method. Part 2: The use of point sources
Atmospheric and Oceanic Optics, 2010The SLOpes Detection And Ranging (SLODAR) method is supplemented with the theory of the measurement of the positions of aberration layers for the case of the use of point reference sources having converging/diverging wavefronts. We determine the dependence of the shift in the correlation peak on the distance to the measured aberration layer, the ...
S. O. Galetskiy, T. Yu. Cherezova
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Atmospheric Measurement Techniques
. Current methods for detecting atmospheric plumes and inferring point-source rates from high-resolution satellite imagery are labor-intensive and not scalable with regard to the growing satellite dataset available for methane point sources.
Jack H. Bruno +3 more
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. Current methods for detecting atmospheric plumes and inferring point-source rates from high-resolution satellite imagery are labor-intensive and not scalable with regard to the growing satellite dataset available for methane point sources.
Jack H. Bruno +3 more
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Science of the Total Environment, 2020
The classic export coefficient model has been questioned due to its fixed coefficient, especially for those large-scale watersheds where great temporal-spatial heterogeneity exists.
Wenzhuo Wang, Lei Chen, Zhenyao Shen
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The classic export coefficient model has been questioned due to its fixed coefficient, especially for those large-scale watersheds where great temporal-spatial heterogeneity exists.
Wenzhuo Wang, Lei Chen, Zhenyao Shen
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Complex point-source representation of real point sources and the Gaussian beam summation method
Journal of the Optical Society of America A, 1986A new exact representation for point sources is given in terms of complex point sources. In the simplest configuration, a point source is equivalent to a distribution of sources on the surface of a sphere in complex space. The representation can be used to consider the propagation of point disturbances through inhomogeneous media and across interfaces.
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