Tracking of time-evolving sound speed profiles in shallow water using an ensemble Kalman-particle filter

Author Posting. © Acoustical Society of America, 2013. This article is posted here by permission of Acoustical Society of America for personal use, not for redistribution. The definitive version was published in Journal of the Acoustical Society of America 133 (2013): 1377-1386, doi:10.1121/1.4790354.This paper presents a tracking technique for performing sequential geoacoustic inversion monitoring range-independent environmental parameters in shallow water. The inverse problem is formulated in a state-space model with a state equation for the time-evolving sound speed profile (SSP) and a measurement equation that incorporates acoustic measurements via a hydrophone array. The particle filter (PF) is an ideal algorithm to perform tracking of environmental parameters for nonlinear systems with non-Gaussian probability densities. However, it has the problem of the mismatch between the proposal distribution and the a posterior probability distribution (PPD). The ensemble Kalman filter (EnKF) can obtain the PPD based on the Bayes theorem. A tracking algorithm improves the performance of the PF by employing the PPD of the EnKF as the proposal distribution of the PF. Tracking capabilities of this filter, the EnKF and the PF are compared with synthetic acoustic pressure data and experimental SSP data. Simulation results show the proposed method enables the continuous tracking of the range-independent SSP and outperforms the PF and the EnKF. Moreover, the complexity analysis is performed, and the computational complexity of the proposed method is greatly increased because of the combination of the PF and the EnKF.This work was supported by the National High Technology Research and Development Program of China (Grant No. 2012AA090901), the National Natural Science Foundation of China (Grant No. 61171147), and the State Key Laboratory of Acoustics, Chinese Academy of Sciences (Grant No. SKLOA201102)

THE DEVELOPMENT OF CCD RANGE FINDER

Application of a range finder in both indoor and outdoor settings shows that distance and subject information can be performed accurately. The range finder can measure the distance, show the performance and do the management task at the same time. It is adapted to any climate and can work in different conditions. It has the characteristics of being cheap, convenient, quick and accurate

The W-weighted Drazin-star matrix and its dual

[EN] After decades studying extensively two generalized inverses, namely Moore--Penrose inverse and Drazin inverse, currently, we found immersed in a new generation of generalized inverses (core inverse, DMP inverse, etc.). The main aim of this paper is to introduce and investigate a matrix related to these new generalized inverses defined for rectangular matrices. We apply our results to the solution of linear systems.The authors wish to thank the editor and reviewers sincerely for their constructive comments and suggestions that have improved the quality of the paper. This research is supported by the Postgraduate Research and Practice Innovation Program of Jiangsu Province (No. KYCX18_0053), the China Scholarship Council (File No. 201906090122), the National Natural Science Foundation of China (No.11771076, 11871145). The third author is partially supported by Ministerio de Economía y Competitividad of Spain (grant Red de Excelencia MTM2017-90682-REDT) and Universitat Nacional de La Pampa, Facultad de Ingeniería (Grant Resol. No. 135/19)Zhou, M.; Chen, J.; Thome, N. (2021). The W-weighted Drazin-star matrix and its dual. The Electronic Journal of Linear Algebra. 37:72-87. https://doi.org/10.13001/ela.2021.5389S72873

Characterizations and perturbation analysis of a class of matrices related to core-EP inverses

[EN] Let A, B is an element of C-nxn with ind(A) = k and ind(B) = s and let L-B = (BB)-B-2(sic). A new condition (C-s,C-*): R(A(k)) boolean AND N((B-s)*) = {0} and R(B-s) boolean AND N((A(k))*) = {0}, is defined. Some new characterizations related to core-EP inverses are obtained when B satisfies condition (C-s,C-*). Explicit expressions of B(sic) and BB(sic) are also given. In addition, equivalent conditions, which guarantee that B satisfies condition (C-s,C-*), are investigated. We proved that B satisfies condition (C-s,C-*) if and only if L-B has a fixed matrix form. As an application, upper bounds for the errors parallel to B(sic) - A(sic)parallel to/parallel to A(sic)parallel to and parallel to BB(sic) - AA(sic)parallel to are studied. (c) 2021 Elsevier B.V. All rights reserved.The authors thank the Editor and Reviewers sincerely for their constructive comments and suggestions which have improved the quality of the paper. This research is supported by the National Natural Science Foundation of China (Nos. 11771076, 11871145), the Postgraduate Research and Practice Innovation Program of Jiangsu Province (No. KYCX18 -0053), the China Scholarship Council (File No. 201906090122). The third author is partially supported by Ministerio de Economia y Competitividad of Spain (grant Red de Excelencia MTM2017-90682-REDT) and partially supported by Universidad de Buenos Aires, Argentina. EXP-UBA: 13.019/2017, 20020170100350BAZhou, M.; Chen, J.; Thome, N. (2021). Characterizations and perturbation analysis of a class of matrices related to core-EP inverses. Journal of Computational and Applied Mathematics. 393:1-11. https://doi.org/10.1016/j.cam.2021.113496S11139