Resolving phase ambiguity in dual‐echo dixon imaging using a projected power method

Antioxidant activity of sequential extracts of black pepper, ginger, turmeric and cinnamon was determined by DPPH assay, phosphomolybdate method and ferric reducing power method and compared with that of the synthetic antioxidant BHA. The results revealed that methanol extract of cinnamon has highest antioxidant potential followed by chloroform extract of turmeric. The antioxidant potential was also correlated with total phenol content.

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Hydraulic fluid power. Method to relate the cleanliness of a hydraulic system to the cleanliness of the components and hydraulic fluid that make up the system

10.3403/30166227 ◽

2013 ◽

Keyword(s):

Hydraulic System ◽

Fluid Power ◽

Hydraulic Fluid ◽

Power Method

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An efficient method for carrier phase ambiguity resolution in GPS attitude determination

IET International Conference on Wireless Mobile and Multimedia Networks Proceedings (ICWMMN 2006) ◽

10.1049/cp:20061541 ◽

2006 ◽

Cited By ~ 2

Author(s):

Zhijin Zhao ◽

Qi Gao ◽

Weiguo Hu

Keyword(s):

Efficient Method ◽

Ambiguity Resolution ◽

Carrier Phase ◽

Attitude Determination ◽

Phase Ambiguity ◽

Phase Ambiguity Resolution ◽

Carrier Phase Ambiguity

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Iterative Methods for the Computation of the Perron Vector of Adjacency Matrices

Mathematics ◽

10.3390/math9131522 ◽

2021 ◽

Vol 9 (13) ◽

pp. 1522

Author(s):

Anna Concas ◽

Lothar Reichel ◽

Giuseppe Rodriguez ◽

Yunzi Zhang

Keyword(s):

Iterative Methods ◽

Adjacency Matrix ◽

Lanczos Method ◽

Power Method ◽

Arnoldi Method ◽

Multiple Eigenvalues ◽

Computer Storage ◽

Adjacency Matrices ◽

Lanczos Methods ◽

Perron Vector

The power method is commonly applied to compute the Perron vector of large adjacency matrices. Blondel et al. [SIAM Rev. 46, 2004] investigated its performance when the adjacency matrix has multiple eigenvalues of the same magnitude. It is well known that the Lanczos method typically requires fewer iterations than the power method to determine eigenvectors with the desired accuracy. However, the Lanczos method demands more computer storage, which may make it impractical to apply to very large problems. The present paper adapts the analysis by Blondel et al. to the Lanczos and restarted Lanczos methods. The restarted methods are found to yield fast convergence and to require less computer storage than the Lanczos method. Computed examples illustrate the theory presented. Applications of the Arnoldi method are also discussed.

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The Global Convergence of the Nonlinear Power Method for Mixed-Subordinate Matrix Norms

Journal of Scientific Computing ◽

10.1007/s10915-021-01524-w ◽

2021 ◽

Vol 88 (1) ◽

Author(s):

Antoine Gautier ◽

Matthias Hein ◽

Francesco Tudisco

Keyword(s):

Global Convergence ◽

Convergence Theorem ◽

Matrix Norm ◽

Nonnegative Matrices ◽

Np Hard ◽

Power Method ◽

Contraction Ratio ◽

Matrix Norms ◽

Vector Norms

AbstractWe analyze the global convergence of the power iterates for the computation of a general mixed-subordinate matrix norm. We prove a new global convergence theorem for a class of entrywise nonnegative matrices that generalizes and improves a well-known results for mixed-subordinate $$\ell ^p$$ ℓ p matrix norms. In particular, exploiting the Birkoff–Hopf contraction ratio of nonnegative matrices, we obtain novel and explicit global convergence guarantees for a range of matrix norms whose computation has been recently proven to be NP-hard in the general case, including the case of mixed-subordinate norms induced by the vector norms made by the sum of different $$\ell ^p$$ ℓ p -norms of subsets of entries.

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