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Effects of Phase Aberration and Phase Aberration Correction on the Minimum Variance Beamformer
Ultrasonic Imaging, 2017The minimum variance (MV) beamformer has the potential to enhance the resolution and contrast of ultrasound images but is sensitive to steering vector errors. Robust MV beamformers have been proposed but mainly evaluated in the presence of gross sound speed mismatches, and the impact of phase aberration correction (PAC) methods in mitigating the ...
Gustavo, Chau +2 more
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Connection between uniformity and minimum moment aberration
Metrika, 2008zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Qin, Hong +2 more
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Minimum Lee-moment aberration and its applications
SCIENTIA SINICA Mathematica, 2016Various criteria have been proposed to compare and assess fractional factorial designs. Among them the minimum moment aberration criterion is conceptually simple and computationally cheap. However, the power moments in the minimum moment aberration criterion depend on the Hamming distances between two runs, which leads to minimum moment aberration ...
Hong QIN, Na ZOU
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Minimum and absolute minimum spherical aberration of a simple, thin lens
American Journal of Physics, 1980Traditional treatments of third-order spherical aberration of a thin lens express the results in terms of a function Ls, involving a lens shape factor q and an object-image position factor p. The function Ls is defined in terms of the difference of the reciprocal paraxial and zonal image distances instead of the difference in distances, which is ...
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Minimum aberration designs with two-level and four-level-factors
Biometrika, 1993Summary: For optimal assignment of factors to columns of a \(4^ m 2^ n\) design, we consider extensions of the minimum aberration criterion for the 2- level designs. Minimum aberration \(4^ 1 2^ n\) and \(4^ 2 2^ n\) designs in 16 and 32 runs are obtained and tabulated. Some results on the wordlength patterns and design classification are obtained.
Wu, C. F. J., Zhang, Runchu
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Minimum aberration blocked designs with multiple block variables
Metrika, 2020Blocked fractional factorial designs are used to treat inhomogeneity of the experimental units. Mostly (and for simplicity) blocked designs with a single block variable can be found in the literature. In practice, however, inhomogeneity often comes from multiple block variables.
Shengli Zhao, Qianqian Zhao
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Sensitivity of minimum variance beamforming to tissue aberrations
2008 IEEE Ultrasonics Symposium, 2008Minimum variance beamformers adapt to the received data. In the case of perfect data, this beamformer can produce images with better point and edge definitions than conventional delay-and-sum beamformers. But in medical ultrasound imaging, the quality of the data is often corrupted by aberration.
Andreas Austeng +5 more
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Split-Plot Fractional Designs: Is Minimum Aberration Enough?
Journal of Quality Technology, 2006Split-plot experiments are commonly used in industry for product and process improvement. Recent articles on designing split-plot experiments concentrate on minimum aberration as the design criterion. Minimum aberration has been criticized as a design criterion for completely randomized fractional factorial design and alternative criteria, such as the ...
Murat Kulahci +2 more
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Quadrupole-Octopole Aberration Correctors with Minimum Fields
Review of Scientific Instruments, 1971Magnetic quadrupole-octopole systems are treated theoretically. A technique is given for finding the minimum octopole field that will correct any geometrical aberration of any orthogonal quadrupole system. It is demonstrated with the correction of aperture aberration and coma in anamorphotic and orthomorphic objective type systems. Further minimization
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Minimum aberration majorization in non-isomorphic saturated designs
Journal of Statistical Planning and Inference, 2004zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Fang, Kai Tai, Zhang, Aijun
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