TY - JOUR AU - Elkattan, M. AU - Kamel, A. TI - Characterization of electromagnetic parameters through inversion using metaheuristic technique JF - INVERSE PROBLEMS IN SCIENCE AND ENGINEERING J2 - INVERSE PROBL SCI EN VL - 29 PY - 2021 IS - 4 SP - 567 EP - 585 PG - 19 SN - 1741-5977 DO - 10.1080/17415977.2020.1797718 UR - https://m2.mtmt.hu/api/publication/32623203 ID - 32623203 N1 - Export Date: 26 January 2022 Correspondence Address: Elkattan, M.; Department of Electronics, Egypt; email: emtiazegf@hotmail.com AB - Inverse problems are of importance in many fields of science and engineering. Electromagnetic inversion deals with estimating information contained in electromagnetic measurements. The inversion scheme needs to be designed properly to compensate for Gibbs oscillations effects in the solution, and hence give better validation for the estimated quantities. In this paper an inversion methodology based on simulated annealing is presented that has the ability to extract information about electrical conductivity and dielectric permittivity of a vertically stratified medium using the scattered electric field. Furthermore, Gibbs phenomenon and its oscillation effect on the inversion solution have been studied, and an efficient approach has been developed to render more accurate estimations. Results of implementing the proposed approach and its resolution compared with the original methodology are presented. © 2020 Informa UK Limited, trading as Taylor & Francis Group. LA - English DB - MTMT ER - TY - JOUR AU - Zhang, Ge AU - Tang, Liqun AU - Liu, Zejia AU - Zhou, Licheng AU - Liu, Yiping AU - Jiang, Zhenyu AU - Chen, Jingsong AU - Sun, Shuhang TI - Enhanced features in principal component analysis with spatial and temporal windows for damage identification JF - INVERSE PROBLEMS IN SCIENCE AND ENGINEERING J2 - INVERSE PROBL SCI EN VL - 29 PY - 2021 IS - 13 SP - 2877 EP - 2894 PG - 18 SN - 1741-5977 DO - 10.1080/17415977.2021.1954921 UR - https://m2.mtmt.hu/api/publication/33472703 ID - 33472703 AB - Principal component analysis (PCA) methods have been widely applied to damage identification in the long-term structural health monitoring (SHM) of infrastructure. Usually, the first few eigenvector components derived by PCA methods are treated as damage-sensitive features. In this paper, the effective method of double-window PCA (DWPCA) and novel features are proposed for better damage identification performance. In the proposed method, spatial and temporal windows are introduced to the traditional PCA method. The spatial windows are applied to group damage-sensitive sensors and exclude those sensors insensitive to damage, while the temporal window is applied to better discriminate eigenvectors between the damaged and healthy states. In addition, the length and directional angle of the eigenvector variation between the healthy and damaged states are used as the damage-sensitive features, instead of the components of the eigenvector variation used in previous studies. Numerical simulations based on a large-scale bridge reveal that the proposed features are successful in identifying the damage located far from sensors due to the use of both spatial and temporal windows as well as the length of the eigenvector variation. In addition, compared to the previous PCA and moving PCA methods, the novel features have higher sensitivity and resolution in damage identification. LA - English DB - MTMT ER - TY - JOUR AU - Dong, Yiqiu AU - Wu, Chunlin AU - Yan, Shi TI - A fast method for simultaneous reconstruction and segmentation in X-ray CT application JF - INVERSE PROBLEMS IN SCIENCE AND ENGINEERING J2 - INVERSE PROBL SCI EN VL - 29 PY - 2021 IS - 13 SP - 3342 EP - 3359 PG - 18 SN - 1741-5977 DO - 10.1080/17415977.2021.1999941 UR - https://m2.mtmt.hu/api/publication/32559193 ID - 32559193 LA - English DB - MTMT ER - TY - JOUR AU - Fathi, F. AU - Araghi, M. A. Fariborzi AU - Fazeli, S. A. Shahzadeh TI - Inverse singular value problem for nonsymmetric ahead arrow matrix JF - INVERSE PROBLEMS IN SCIENCE AND ENGINEERING J2 - INVERSE PROBL SCI EN VL - 29 PY - 2021 IS - 12 SP - 2085 EP - 2097 PG - 13 SN - 1741-5977 DO - 10.1080/17415977.2021.1902515 UR - https://m2.mtmt.hu/api/publication/32000807 ID - 32000807 AB - Constructing a matrix by its spectral information including singular values is called inverse singular value problem (ISVP). In this paper, an ISVP for nonsymmetric ahead arrow matrix by two eigenpairs of the required matrix and one singular value of each leading principal submatrices is investigated. To solve the problem, the recurrence relation of characteristic polynomial of the block Jordan-Weilant matrix associated with the aim matrix is obtained. The conditions of solvability of the problem are derived. Finally a numerical algorithm and an example are given. LA - English DB - MTMT ER - TY - JOUR AU - Lotfinia, Hussien AU - Chegini, Nabi AU - Mokhtari, Reza TI - The bi-Helmholtz equation with Cauchy conditions: ill-posedness and regularization methods JF - INVERSE PROBLEMS IN SCIENCE AND ENGINEERING J2 - INVERSE PROBL SCI EN VL - 29 PY - 2021 IS - 1 SP - 17 EP - 39 PG - 23 SN - 1741-5977 DO - 10.1080/17415977.2020.1764950 UR - https://m2.mtmt.hu/api/publication/31465858 ID - 31465858 AB - In this paper, the bi-Helmholtz equation with Cauchy conditions is nominated in a n-dimensional strip domain. It is shown that this Cauchy problem may be ill-posed in the sense of Hadamard. In order to overcome the ill-posedness, a suitable regularization method has to be applied to the Cauchy problem. Hence, two well-known wavelet and Fourier regularization methods are used for solving this ill-posed problem. Regarding our experiences, wavelet and Fourier regularization methods act similarly, since these methods remove high frequencies in the frequency space which are the reason for ill-posedness. To explore abilities of the wavelet regularization method, stability of the solution with the Meyer wavelet regularization is investigated by obtaining some error bounds. It is demonstrated numerically that Shannon wavelet is an alternative to the Meyer wavelet in the regularization method. It is explored that the Fourier regularization method for solving the bi-Helmholtz equation with the Cauchy conditions is also applicable. Numerical algorithms of the desired regularization methods are proposed in detail based on the fast Fourier transform (FFT). Various numerical examples in two-dimensional strip domain are shown for the validation and verification of the regularization techniques. LA - English DB - MTMT ER - TY - JOUR AU - Cakmak, Yasar TI - Inverse nodal problem for a conformable fractional diffusion operator JF - INVERSE PROBLEMS IN SCIENCE AND ENGINEERING J2 - INVERSE PROBL SCI EN PY - 2020 PG - 15 SN - 1741-5977 DO - 10.1080/17415977.2020.1847103 UR - https://m2.mtmt.hu/api/publication/31701881 ID - 31701881 AB - In this paper, a second order differential pencil, namely diffusion equation with Dirichlet boundary conditions which includes conformable fractional derivatives of order alpha(0 < alpha <= 1) instead of the ordinary derivatives in a traditional diffusion operator, is considered. Firstly, the asymptotic formulae of eigenvalues and eigenfunctions of the operator are obtained. Secondly, the nodal points which are the zeros of the eigenfunction of the operator are investigated. Later, an effective procedure for solving the inverse nodal problem is given and thus the potentials of the diffusion operator are reconstructed with the help of a dense subset of nodal points. Finally, an example to illustrate the theoretical findings of this study is presented. LA - English DB - MTMT ER - TY - JOUR AU - Wei, Xianbiao AU - Miao, Hongyi AU - Ge, Cishui AU - Zhao, Chengbing TI - An inverse problem for Sturm-Liouville operators with nodal data on arbitrarily-half intervals JF - INVERSE PROBLEMS IN SCIENCE AND ENGINEERING J2 - INVERSE PROBL SCI EN PY - 2020 PG - 13 SN - 1741-5977 DO - 10.1080/17415977.2020.1779711 UR - https://m2.mtmt.hu/api/publication/31445777 ID - 31445777 AB - Inverse nodal problems for the Sturm-Liouville operator are to reconstruct this operator from the given nodal points(zeros) of its eigenfunctions. In this paper, the potential q(x) up to its mean value on the whole interval is uniquely determined by two adjacent twin-dense nodal subsets on arbitrarily-half subintervals corresponding to eigenvalues with various boundary conditions and an example on numerical solutions for reconstructing q(x) from a nodal subset on [0,1] is presented. LA - English DB - MTMT ER - TY - JOUR AU - Ustinov, Vladislav D. AU - Tsybrov, Evgeniy G. TI - Numerical reconstruction of two-dimensional particle size distributions from laser diffraction data JF - INVERSE PROBLEMS IN SCIENCE AND ENGINEERING J2 - INVERSE PROBL SCI EN PY - 2020 PG - 15 SN - 1741-5977 DO - 10.1080/17415977.2020.1761801 UR - https://m2.mtmt.hu/api/publication/31436178 ID - 31436178 AB - In this paper, we consider the two-dimensional Fredholm integral equation of the first kind. The kernel of this equation models the scattering of a laser beam by spheroids having the same fixed orientation. The unknown function under the integral describes the distribution of spheroids along two semi-axes. The input data are the diffraction pattern corresponding to the scattering of the laser beam by the particles. We show that the Tikhonov regularization method allows one to reconstruct two-dimensional distributions in the case when the diffraction pattern is modulated by white noise with relative amplitude up to 1%. In applications, this means novel possibility of obtaining two-dimensional particle size distributions, rather than one-dimensional ones, as in the classical version of the method. This significantly expands the capabilities of particle sizing via static laser diffraction technique. We show that the solution of the corresponding equation is unique in space and exists when the right-hand-side function is in a set dense in . We provide test experimental results in the framework of laser ektacytometry of red blood cells, which serves as the main application of the proposed approach presently. LA - English DB - MTMT ER - TY - JOUR AU - Kuramshina, Gulnara M. AU - Kochikov, Igor V. AU - Sharapova, Svetlana A. TI - Regularizedab initiomolecular force fields for key biological molecules: melatonin and pyridoxal-5 '-phosphate methylamine Shiff base (Vitamin B6) JF - INVERSE PROBLEMS IN SCIENCE AND ENGINEERING J2 - INVERSE PROBL SCI EN PY - 2020 PG - 18 SN - 1741-5977 DO - 10.1080/17415977.2020.1797717 UR - https://m2.mtmt.hu/api/publication/31410495 ID - 31410495 N1 - Department of Physical Chemistry, Faculty of Chemistry, Lomonosov Moscow State University, Moscow, Russian Federation Scientific Research Computer Centre, Lomonosov Moscow State University, Moscow, Russian Federation Cited By :1 Export Date: 15 May 2023 Correspondence Address: Kuramshina, G.M.; Department of Physical Chemistry, Russian Federation; email: kuramshi@phys.chem.msu.ru AB - The main mathematical results on the data processing in vibrational spectroscopy are presented. The approaches and algorithms proposed for molecular force field calculations have been constructed on a base of regularizing methods for solving nonlinear ill-posed problems and have been implemented in the software package SPECTRUM. These algorithms were used for constructing the regularizedab initioforce fields of important biological molecules including the melatonin and Vitamin B6 derivatives. LA - English DB - MTMT ER - TY - JOUR AU - Delbary, Fabrice AU - Hanke, Martin AU - Ivanizki, Dmitry TI - A generalized Newton iteration for computing the solution of the inverse Henderson problem JF - INVERSE PROBLEMS IN SCIENCE AND ENGINEERING J2 - INVERSE PROBL SCI EN VL - 28 PY - 2020 IS - 8 SP - 1166 EP - 1190 PG - 25 SN - 1741-5977 DO - 10.1080/17415977.2019.1710504 UR - https://m2.mtmt.hu/api/publication/31457091 ID - 31457091 N1 - Cited By :3 Export Date: 26 May 2023 Correspondence Address: Hanke, M.; Institut für Mathematik, Germany; email: hanke@mathematik.uni-mainz.de AB - We develop a generalized Newton scheme called IHNC (inverse hypernetted-chain iteration) for the construction of effective pair potentials for systems of interacting point-like particles. The construction is realized in such a way that the distribution of the particles matches a given radial distribution function. The IHNC iteration uses the hypernetted-chain integral equation for an approximate evaluation of the inverse of the Jacobian of the forward operator. In contrast to the full Newton method realized in the Inverse Monte Carlo (IMC) scheme, the IHNC algorithm requires only a single molecular dynamics computation of the radial distribution function per iteration step and no further expensive cross-correlations. Numerical experiments are shown to demonstrate that the method is as efficient as the IMC scheme, and that it easily allows to incorporate thermodynamical constraints. LA - English DB - MTMT ER -