Article
Chemistry, Analytical
Gilsu Yeo, Myungjin Cho
Summary: This paper proposes a new method for three-dimensional visualization of objects at long distance under photon-starved conditions. The method utilizes digital zooming to improve visual quality by cropping and interpolating the region of interest from the image. Photon counting integral imaging is used to reconstruct three-dimensional images, and multiple observation photon counting integral imaging is employed for more accurate estimation. Optical experiments and performance metrics calculation demonstrate the feasibility and effectiveness of the proposed method in improving the visualization of three-dimensional objects at long distances under photon-starved conditions.
Article
Chemistry, Analytical
Jae-Young Jang, Myungjin Cho
Summary: In this paper, a lensless three-dimensional (3D) imaging method under photon-starved conditions is proposed using diffraction grating and computational photon counting. Traditional 3D imaging is challenging under photon-starved conditions due to the lack of photons. To tackle this, the proposed method utilizes diffraction grating imaging for lensless 3D imaging and computational photon counting for 3D visualization. Additionally, a multiple observation photon counting method with advanced statistical estimation such as Bayesian estimation is introduced to improve the visual quality of severely photon-starved 3D images.
Article
Chemistry, Analytical
Hyun-Woo Kim, Myungjin Cho, Min-Chul Lee
Summary: This study focuses on the research of three-dimensional reconstruction under low illumination environment. Photon-counting integral imaging is a technique to visualize 3D images under low light conditions. However, the conventional method has the issue of randomness due to the temporal and spatial independence of Poisson random numbers. In this paper, the Kalman filter is applied to improve the visual quality by correcting the errors in the photon-counting integral imaging. The proposed method shows better structure similarity, peak signal-to-noise ratio, and cross-correlation values compared to the conventional method, indicating a more accurate visualization of low illuminated images. Furthermore, it is expected to contribute to the development of autonomous driving technology and security camera technology.
Article
Physics, Multidisciplinary
Mikhail Umanskii, Alexey N. Rubtsov
Summary: The original formulation of the boson sampling problem assumed little or no photon collisions. However, modern experiments often have a high number of collisions, where the number of injected photons M is close to the number of detectors N. A classical algorithm is presented here to simulate a bosonic sampler, which calculates the probability of a given photon distribution at the outputs of the interferometer for a given distribution at the inputs. This algorithm is particularly effective in cases with multiple photon collisions and outperforms known algorithms in such cases.
Article
Chemistry, Analytical
Jiheon Lee, Myungjin Cho
Summary: This paper proposes an enhancement of three-dimensional image visualization techniques by using different pickup plane reconstructions to improve both the lateral and longitudinal resolutions of 3D objects.
Article
Optics
Jiheon Lee, Myungjin Cho
Summary: This paper proposes enhancing three-dimensional image visualization under photon-starved conditions using preprocessing techniques such as contrast-limited adaptive histogram equalization and histogram matching. The feasibility and performance metrics of the proposed method are demonstrated through an optical experiment.
Article
Chemistry, Analytical
Seung-Chan Lim, Myungjin Cho
Summary: An efficient wireless 3D image transmission system is proposed based on the MIMO technique to reconstruct high-resolution 3D digital content in integral imaging. Multiple elemental images are transmitted simultaneously and recovered with a linear receiver using the spatial multiplexing capability. The proposed system achieves excellent 3D reconstruction performance in terms of visual quality and peak sidelobe ratio.
Article
Computer Science, Information Systems
Jaehoon Lee, Myungjin Cho, Min-Chul Lee
Summary: This paper proposes a novel 3D photon counting double random phase encryption method, which enhances the security and visual quality of data decryption through a random amplitude reconstruction process. The effectiveness of the proposed method is verified through simulations and optical experiments.
Article
Engineering, Electrical & Electronic
Jinbo Liu, Wen Luo, Jiming Song, Zengrui Li
Summary: In this study, the authors propose a new triangular interpolation (TI) method to improve the efficiency of the multilevel fast multipole algorithm (MLFMA) by replacing the commonly used Lagrange interpolation (LI). By reselecting the sampling points on the Ewald sphere to form isosceles triangular data grids and utilizing the TI, the efficiency of MLFMA is further enhanced. The interpolation error in the TI is analyzed in detail and numerical results of typical electromagnetic scattering cases are presented to demonstrate the accuracy and efficiency of the proposed TI-based MLFMA.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2023)
Article
Computer Science, Artificial Intelligence
Tingqing Ye
Summary: This paper applies the three-dimensional uncertain heat equation in practical problems such as average temperature, maximum temperature, minimum temperature, and minimum time of reaching a given temperature, using mathematical tools such as time integral, space integral, extreme value, and first hitting time.
Article
Engineering, Mechanical
Paolo Livieri
Summary: This study extends the use of J-integral to three-dimensional sharp V-notches to evaluate the fatigue life of welded joints under complex loading. By simplifying the procedure, the integration path length is determined by the critical characteristic length of the welded joints, and the position of the maximum JV is numerically calculated using the FE method.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Materials Science, Multidisciplinary
Aofei Mao, Peixun Fan, Loic Constantin, Nan Li, Xi Huang, Bai Cui, Jean-Francois Silvain, Xinwei Wang, Yong Feng Lu
Summary: This study presents an approach to transform 2D patterns into 3D geometries using distributed stress inside a polymer. By introducing controlled stress fields, various shape transformations can be achieved during 2D printing. This method offers a unique way to fabricate complex 3D nanostructures.
APPLIED MATERIALS TODAY
(2022)
Article
Mechanics
Miguel P. Encinar, Javier Jimenez
Summary: The algorithm introduced by Jimenez (J. Fluid Mech., vol. 854, 2018, R1) is used to identify the flow patterns of causal significance in three-dimensional isotropic turbulence. The study finds that the dimensions of the perturbations introduced in the flow are controlled by the kinetic energy content and the enstrophy and dissipation, and affect their significance in the flow. Strain is found to be more efficient than vorticity in propagating the perturbation contents to other regions of the flow. The findings suggest that manipulating strain-dominated vortex clusters is more effective in controlling turbulent flows.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
Chiara Sorgentone, Jeremy I. Kach, Aditya S. Khair, Lynn M. Walker, Petia M. Vlahovska
Summary: This study investigates the electrohydrodynamic interactions between two identical drops in an applied electric field through numerical simulations and analytical theory. The results reveal a complex dynamics dependent on the conductivities and permittivities of the drops and suspending fluids, as well as the initial alignment of the drop pair with the electric field.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Materials Science, Multidisciplinary
Alexis Saez, Brice Lecampion, Pathikrit Bhattacharya, Robert C. Viesca
Summary: This study investigates the quasi-static growth of a fluid-driven shear crack on a fault interface, analyzing the rupture shape and area evolution under different injection scenarios and fault characteristics. The results provide insights into the propagation of stable (aseismic) ruptures and their relationship with fluid pressure increase.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2022)