Article
Mathematics, Applied
Florian Dreier, Markus Haltmeier
Summary: This paper investigates the inverse source problem in photoacoustic tomography (PAT) for mixed data, which refers to a weighted linear combination of the acoustic pressure and its normal derivative on an observation surface. The paper focuses on the scenario where the data is only available within a finite time interval, mirroring real-world usage of PAT. By extending previous work, the authors derive explicit formulas with a smoothing integral on convex domains having a smooth boundary, enabling exact reconstruction for circular or elliptical domains. Numerical reconstructions are also presented and compared to previous formulas that were based on unlimited time wave measurements.
Article
Mathematics
Dorin Andrica, Ovidiu Bagdasar
Summary: This paper presents recent advances in the study of inverse cyclotomic polynomials, including a practical recursive formula for calculating their coefficients and numerical simulations.
Article
Mathematics, Applied
Zekeriya Ustaoglu
Summary: In this paper, we investigate the problem of determining a function from its surface integrals of the second type over n-dimensional circular paraboloids in Rn+1 with fixed focal length and fixed direction of symmetry axis. We obtain some inversion formulas with a method based on the Fourier transform and reducing the reconstruction problem to solving a Volterra integral equation of the first kind. We present some examples on the direct numerical implementations of the resulting inversion formulas.
JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS
(2024)
Article
Mathematics
Michel J. G. Weber
Summary: We present a simple criterion for the infinite Mobius inversion, which is applicable to a wide range of functions.
PUBLICATIONES MATHEMATICAE DEBRECEN
(2023)
Article
Geosciences, Multidisciplinary
Pengfei Liang, Qingyun Di, Changmin Fu, Ruo Wang, Qihui Zhen, Zhe Yun, Jiagang Zhang
Summary: The inversion of magnetotelluric (MT) responses is utilized to investigate the electrical conductivity distribution in the Earth's interior. It is crucial to have a good initial model in three-dimensional (3-D) inversions as the final model is influenced by the initial model. This study presents a two-step 3-D inversion method that focuses on obtaining a one-dimensional (1-D) initial model and then inverting for 3-D conductivity structures, taking into consideration the 3-D topography.
SCIENCE CHINA-EARTH SCIENCES
(2023)
Article
Engineering, Electrical & Electronic
Shih Yu Chang, Hsiao-Chun Wu
Summary: This paper introduces the quantization technique and its application in image compression. A new tensor quantization (TQ) framework is proposed to avoid reducing the dimensionality of image data and destroying the two-dimensional spatial relationship. Experimental results demonstrate the superiority of the TQ approach, especially for high-dimensional images.
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY
(2022)
Article
Statistics & Probability
Xin Ma, Suprateek Kundu
Summary: Recent medical imaging studies have generated distinct but inter-related datasets for multiple experimental tasks or longitudinal visits. This study proposes a novel joint scalar-on-image regression framework to pool information across inter-related images, explicitly accounting for noise in high-dimensional images and deriving nonasymptotic error bounds under nonconvex penalties.
JOURNAL OF THE AMERICAN STATISTICAL ASSOCIATION
(2022)
Article
Engineering, Biomedical
Tasuku Takeda, Hiroshi Fujiwara, Mikio Suga
Summary: A novel inversion algorithm based on the Voigt-type viscoelastic equation has been proposed, improving noise robustness by avoiding direct differentiation of measurement data using Green's formula. Numerical simulations and gel phantom experiments confirmed the effectiveness of the proposed algorithm despite noisy elastic wave images.
INTERNATIONAL JOURNAL OF COMPUTER ASSISTED RADIOLOGY AND SURGERY
(2021)
Article
Engineering, Multidisciplinary
Muhammad Ahsan, Weidong Lei, Amir Ali Khan, Aizaz Ullah, Sheraz Ahmad, Shams Ul Arifeen, Zaheer Uddin, Haidong Qu
Summary: The primary goal of this study is to improve the precision and order of convergence of the Haar wavelet collocation method and apply it to various types of nonlinear ordinary differential equations. The paper also establishes important theorems about the convergence and computational stability of the method. The HHWCM is compared with other existing methods, and different orders of differential equations are tested to showcase its advantages.
ALEXANDRIA ENGINEERING JOURNAL
(2023)
Article
Mathematics, Applied
Xiaoqing Zhao, Yuan Yi
Summary: This paper discusses the high-dimensional Lehmer problem related to Beatty sequences over incomplete intervals and provides an asymptotic formula based on the properties of Beatty sequences and the estimates for hyper Kloosterman sums.
Article
Chemistry, Multidisciplinary
Wen-Feng Deng, Yu-Xia Li, Yan-Xin Zhao, Jie-Sheng Hu, Zi-Shuo Yao, Jun Tao
Summary: Controlling molecular chirality by external stimuli is achieved in a high-temperature molecular ferroelectric Cu(II) complex. The spontaneous polarization of the complex can be switched by flipping the molecular chirality, with the chiral organic cation being converted to its enantiomer using an electric field-induced shift. This perovskite ferroelectric material with simultaneous switching of molecular chirality and spontaneous polarization may result in novel chiral electronic phenomena.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Radiology, Nuclear Medicine & Medical Imaging
Shohei Fujita, Akifumi Hagiwara, Koichiro Yasaka, Hiroyuki Akai, Akira Kunimatsu, Shigeru Kiryu, Issei Fukunaga, Shimpei Kato, Toshiaki Akashi, Koji Kamagata, Akihiko Wada, Osamu Abe, Shigeki Aoki
Summary: This study aimed to investigate the impact of magnetic resonance fingerprinting (MRF) dictionary design on radiomic features in human brain scans. The results showed that MRF-based radiomic features had high repeatability, but caution should be taken when using datasets generated from different dictionaries.
EUROPEAN RADIOLOGY
(2022)
Article
Biochemical Research Methods
Hirofumi Kobayashi, Keith C. Cheveralls, Manuel D. Leonetti, Loic A. Royer
Summary: Cytoself is a self-supervised deep learning-based approach that accurately predicts and clusters protein localization from fluorescence images, providing insights into the diversity and complexity of cellular architecture.
Article
Mathematics
Jiamin Li, Jing Ma
Summary: This paper studies a small arithmetic function and its sum as x approaches infinity, which generalizes previous works and combines different types of sums.
JOURNAL OF NUMBER THEORY
(2023)
Article
Mathematics, Applied
F. S. Naranjo-Noda, J. C. Jimenez
Summary: This paper discusses the numerical computation of high dimensional multiple integrals involving matrix exponentials that can be rewritten as the product of a matrix exponential times vector. In addition to the conventional iterative methods for computing the action of the matrix exponential on a vector, iterative methods for the action of the phi-function over a vector are also considered. A Krylov-Pade approximation to the product of phi-function times vector is used to illustrate the potential for computing various high dimensional multiple integrals in applied mathematics, model identification, control engineering, and numerical methods.
JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS
(2023)
