International Journal of Applied Electromagnetics and Mechanics - Volume 71, issue S1

Authors: Antonopoulos, Christos | Theodoulidis, Theodoros

Article Type: Editorial

DOI: 10.3233/JAE-239001

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S1-S2, 2023

Authors: Peponis, Dimitrios | Latsas, George | Tigelis, Ioannis

Article Type: Research Article

Abstract: In this work we investigated the scattering parameters and mode conversion of axisymmetric TE modes in smooth cylindrical waveguides with wedge-shaped azimuthal corrugations. In particular, we studied the effect of the length of the corrugated region on the scattering parameters and on the mode conversion. The field distribution was derived by the FDTD code COCHLEA and further post-processed using the COPP code. Results showed that the incident mode is converted to an ensemble of modes, the azimuthal indices of which are given by the SHM criterion. Azimuthal corrugated waveguides are usually employed in the gyrotron beam-tunnel to enhance the suppression …of the parasitic modes. Show more

Keywords: FDTD, computational electromagnetics, gyrotron, beam tunnels

DOI: 10.3233/JAE-220094

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S3-S12, 2023

Authors: Ma, Guoliang | Zhang, Meng | Wang, Hongxi | Song, Siyang

Article Type: Research Article

Abstract: In the field of intelligent drive and sense, the traditional actuator can realize linear actuation and lacks sensing function. Therefore, a new sensing actuator is designed, which can not only output force and displacement, but also have thrust anti-torque sensing function. Firstly, the model of piezoelectric actuator is designed, and the geometric and mechanical models are established. Furthermore, the geometric relationship of mechanical and electrical parameters is analyzed. Secondly, the optimal included angles are determined after finite element analysis and optimization. Finally, the maximum output displacement is obtained through finite element analysis, and the maximum strain position is pointed out. …Besides, the rotational stiffness is obtained. The results show that the modeling method and simulation results are accurate. Show more

Keywords: Piezoelectric, actuator, maximum strain

DOI: 10.3233/JAE-220097

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S13-S19, 2023

Authors: Liu, Ping | Wang, Cheng | Chen, Jianwei | Chen, Yewang

Article Type: Research Article

Abstract: In order to identify more high order modal from a small amount of vibration response signal sampling, this paper proposes a method for identifying the OMA of sub-sampled vibration response signals based on compression sensing (CS) and fast independent component analysis (FastICA). Firstly, the method subsamples a large number of vibrational signals to retain the original key information of the signal; Secondly, the subsampled signal is restored by using the compressive sampling matching pursuit (CoSaMP) algorithm of the compression-aware reconstruction algorithm. Finally, the source signal is separated by FastICA to obtain the multi-order natural frequencies and modal mode shapes of …the structure. According to Shannon’s theorem, if the analog signal is reproduced without distortion, the sampling frequency should be no less than 2 times the highest frequency in the analog signal spectrum. This method can reduce the amount of original signal acquisition and the requirements for the frequency of the sampled signal, and the recovery signal has a high similarity with the original signal and the natural frequency is not changed. It can effectively identify the higher-order modes of the structure on the basis of breaking through the Nyquist sampling frequency. Experimental results of the subsampled vibration response signal on the uniform steel cantilever beam show that the method can reconstruct the original signal from a small number of subsampled vibration response signals, and identify the high-order nature frequency and modal mode shape that break through the Nyquist sampling frequency. Show more

Keywords: Operational modal analysis, sub-sampled, compressed sensing, FastICA

DOI: 10.3233/JAE-220099

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S21-S28, 2023

Authors: Song, Haicheng | Yusa, Noritaka

Article Type: Research Article

Abstract: In this study, a multivariable probability of detection (POD) model is developed to quantify the detection capability of a low frequency electromagnetic (LFEM) testing method with permanently installed sensors to monitor the thinning of pipe walls. Numerical simulations are utilized to predict the signal response by modeling LFEM testing against local wall thinning with different profiles. By probabilistically calibrating the simulated signal response with a limited number of experimental samples, signal response distributions due to various flaw profiles are inferred. Subsequently, a model is developed using Monte Carlo simulation to determine the distribution of the signal response affected by sensor …placement and to calculate the POD. The resultant POD contours reflect the effect of multiple flaw parameters and sensor placement on the detection capability of the LFEM testing method. Show more

Keywords: Electromagnetic non-destructive evaluation, probability of detection, sensor network

DOI: 10.3233/JAE-220100

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S29-S37, 2023

Authors: Sasayama, Teruyoshi | Guo, Ziwei

Article Type: Research Article

Abstract: Rectangular wave eddy current testing (RECT), which is performed using a rectangular wave excitation current, can simultaneously obtain multiple datasets. However, the high-frequency harmonic signal detected by the detection coil interferes with the low-frequency signal based on Faraday’s law of induction. The method proposed in this study is a type of electronic bridge, wherein a compensation method is implemented to enhance the low-frequency signal of the RECT using a digital-to-analog converter (DAC). The compensation wave generated by the DAC is determined such that the output signal becomes zero when the probe does not detect any flaws. A 12 mm thick …aluminum plate with flat-bottom drill holes on the backside is used as the specimen. The holes have a diameter of 3 mm and depths of 2, 4, and 6 mm, respectively. The results demonstrate that the flaw signal cannot be detected without compensation. However, the flaw signal can be successfully detected around these holes with compensation. Show more

Keywords: Eddy current testing, low frequency, rectangular wave eddy current testing, digital-to-analog converter, electronic bridge

DOI: 10.3233/JAE-220106

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S39-S46, 2023

Authors: Sun, Zhen | Sato, Takahiro | Watanabe, Kota

Article Type: Research Article

Abstract: A novel hybrid optimization (HO) method efficiently combines parameter optimization (PO) and topology optimization (TO) is proposed. The novelty concerns introducing the mesh deformation technique for model regeneration to make a connection between the TO and PO, in this way, the geometric features can be inherited in iterative optimization to fasten the convergence. The proposed HO is applied to the optimal design of a baseline V-type permanent magnet synchronous machine (PMSM), in which the topology of air barriers and the layout parameters of permanent magnets (PMs) are simultaneously optimized, for torque property enhancement. Comparative numerical results show that the proposed …HO is more efficient in optimal solution searching compared with traditional methods, as good topological features can be inherited in the iterative optimization. The numerical results also indicate that the proposed HO has good compatibility with different solvers, it can always provide good convergence to provide PMSM designs with excellent torque property when an evolutionary algorithm such as a genetic algorithm and evolution strategy is used as the solver. Show more

Keywords: Finite element analysis, gaussian distribution, mesh deformation algorithm, permanent magnet machine, topology optimization

DOI: 10.3233/JAE-220108

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S47-S56, 2023

Authors: Meis, Constantin

Article Type: Research Article

Abstract: Without stating postulates or advancing any hypothesis, we show that a physical representation for the photon results directly from Maxwell’s theory once the vector potential amplitude is normalized at a single photon level. Electromagnetic waves are composed of a superposition of single photon states with circular polarizations, each extended over a wavelength and occupying a specific quantization volume. This representation is valid at any frequency and consequently can be applied for the modeling of advanced devices ranging from X-Rays and UV applications to fiber optics, microwave antennas and radio waves emitters.

Keywords: Electromagnetic waves, photons, quantized vector potential field, electromagnetic field

DOI: 10.3233/JAE-220111

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S57-S63, 2023

Authors: Tanaka, Yoshikazu | Simojyo, Kazuki

Article Type: Research Article

Abstract: The magnetic targeting method is expected for the regeneration of cartilage of knee. Magnetically labeled mesenchymal stem cells (m-MSCs) and an external magnetic field are used in the magnetic targeting method. A numerical calculation method for simulating the behavior of the m-MSC is needed. In this paper a numerical calculation method of magnetization and eddy current by applying the subdomain method to integral equations is presented. The proposed method has been used to solve two problems for which the exact solutions are known, namely the magnetization of a sphere placed in a uniform magnetic field and the eddy current induced …in a flat plate, to verify its validity. Through the two problems, the validity of the proposed method has been confirmed. Show more

Keywords: m-MSCs, integral equations, subdomain method, magnetization, eddy current

DOI: 10.3233/JAE-220117

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S65-S74, 2023

Authors: Tomizawa, Takuma | Guo, Yijun | Yusa, Noritaka

Article Type: Research Article

Abstract: In this study, a simulation-assisted probability of detection (POD) analysis that considers multiple flaw parameters and signal features is presented, including an evaluation of its applicability to eddy current testing for weld inspection. In the proposed method, both the real and imaginary parts of eddy current signals were considered, unlike conventional methods that only consider signal amplitude. Type 304 stainless steel plates were joined by butt welding, and slits were fabricated on the weld path. The eddy current inspection was conducted using a uniform eddy current probe. Numerical simulations were also performed using the finite element method, with the model …imitating the experimental situation. The POD contours were calculated using the proposed method, and they exhibited a reasonable tendency. In addition, the 95% lower confidence intervals of the proposed and conventional PODs were compared and were almost equal with respect to the decision threshold, indicating the applicability of the proposed method. Show more

Keywords: Multi-parameter, POD, slit, butt weld, detection capability, uniform eddy current, stainless steel

DOI: 10.3233/JAE-220123

Citation: International Journal of Applied Electromagnetics and Mechanics, vol. 71, no. S1, pp. S75-S83, 2023