Results 21 to 30 of about 4,408 (211)
International Journal of Distributed Sensor Networks, 2021 Imperfection in a bonding point can affect the quality of an entire integrated circuit. Therefore, a time–frequency analysis method was proposed to detect and identify fault bonds.
Wuwei Feng +3 more
doaj +1 more source
On Two-Dimensional Quaternion Wigner-Ville Distribution
Journal of Applied Mathematics, 2014 We present the two-dimensional quaternion Wigner-Ville distribution (QWVD). The transform is constructed by substituting the Fourier transform kernel with the quaternion Fourier transform (QFT) kernel in the classical Wigner-Ville distribution definition.
Mawardi Bahri
doaj +1 more source
Statistical Study of the Entanglement for Qubit Interacting with an Electromagnetic Field
Advances in Mathematical Physics, 2021 A statistical method is applied to predict the behaviour of a quantum model consisting of a qubit interacting with a single-mode cavity field. The qubit is prepared in excited state while the field starts from the binomial distribution state.
Neveen Sayed-Ahmed +6 more
doaj +1 more source
Post-Earthquake Damage Identification of Buildings with LMSST
Buildings, 2023 The structure is said to be damaged if there is a permanent shift in the post-event natural frequency of a structure as compared with the pre-event frequency. To assess the damage to the structure, a time-frequency approach that can capture the pre-event
Roshan Kumar +2 more
doaj +1 more source
Robust and fast algorithm for extracting the periodic feature from jet engine modulation signals
The Journal of Engineering, 2019 Jet engine modulation (JEM), a modulation phenomenon induced by the rotating structure of jet engines, is a representative feature extracted from the radar returns for aircraft target recognition.
Jingming Sun, Junpeng Yu
doaj +1 more source
SAR ground moving target's along-track velocity estimation in the complex image domain via SoWVD
The Journal of Engineering, 2019 A ground moving target is always defocused in the synthetic aperture radar (SAR) image domain due to the along-track velocity. In the image domain, a moving target's complex response along the azimuth direction can be modelled as a linear frequency ...
Zuzhen Huang +3 more
doaj +1 more source
ANALOGY OF THE SECOND ORDER PHASE TRANSITION IN QUASI-OPTICAL MICROWAVE CAVITY RESONATOR [PDF]
Радиофизика и электроника, 2015 In this paper for the first time we have discovered and studied the analogy of the second order phase transition in spheri-cal microwave cavities with heterogeneity in the form of a metal ball. The transition occurs between the state when the ball is sym-
E. M. Ganapolskii
doaj +1 more source
Spectral analysis of ultrasonic signals backscartted by mortar: Effect of sand size and temperatures
Materials Letters: X, 2022 This paper presents results of application of Ultrasonic Waves UW in civil engineering. The measurement has been performed by ultrasonic reflection technique using a transducer with central frequency 0,5MHz.
Hicham LOTFI +3 more
doaj +1 more source
Uncertainty principles for coupled fractional Wigner–Ville distribution
Royal Society Open ScienceThe coupled fractional Wigner–Ville distribution is a more general version of the fractional Wigner–Ville distribution. Main properties including boundedness, Moyal’s formula and inversion formula are studied in detail for the transformation ...
Andi Tenri Ajeng Nur +3 more
doaj +1 more source
Feature Extraction of Gear Fault Signal Based on Sobel Operator and WHT
Shock and Vibration, 2013 Taking Wigner-Ville distribution of gear fault signal as a picture, Sobel operator was applied for edge detection of picture and then Hough transform was used to extract signal feature.
Jian-Hua Cai, Wei-Wen Hu
doaj +1 more source