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This paper analysis the magnetic features including flux linkage and air-gap flux density in interior permanent magnet synchronous motor (IPMSM) with delta-shaped PM used for electric vehicles (EVs). Research motor models are based on the motor of Nissan Leaf called EM61 taken from experiment reports, and the analysis is based on finite element analysis (FEA). The analysis is performed by adjusting the existence of permanent magnets (PMs) and flux barriers (FBs) as well as the amplitude and phase angle of excitation current which affect the torque production, phase flux linkage, and air-gap flux density under two temperature conditions. Through this analysis, the influence of each object, its position (i.e., the inner and outer layer of PM and FB), and PM-FB interaction on the magnetic features of IPMSM are expressed. The role of these PM-FBs on magnetic features also helps to point out some indications for engineers when designing an IPMSM.

In the present research, fountain solution without isopropyl alcohol (IPA) for Ultraviolet offset curing ink (UV ink) was prepared by using Ethylene Glycol Mono-butyl Ether (EGME) as a substitute for IPA. The effect of EGME concentration on the water pick-up characteristics, tack value, rheological behaviors, and curing time of UV offset inks was investigated. Water pick-up characteristics, tack value and rheological behaviors were measured by Duke Ink water emulsification tester, Tack-o-scope and cone-plate rheometer, respectively. The curing time of the UV ink was evaluated by the rub test of printed sheet samples proofed on the polymer film at the standard solid ink density and the same ink thickness. The results revealed that an increase in EGME concentration increased the water pick-up characteristics of the UV ink. There was no significant influence of EGME on the tack value of UV inks. However, the tack value of UV ink was significantly affected by fountain concentration in UV inks and UV ink color. The addition of EGME reduced the dynamic viscosity and thixotropic property of UV inks but did not change the flow behavior of UV ink as shear thinning. This study indicates that UV ink emulsified with a higher EGME concentration fountain solution needs a longer curing time. The cyan UV ink has the longest curing time. Finally, the fountain solution of 10% EGME exhibited good performance in water pick-up characteristics, tack value, rheological behaviors, and curing time of UV inks.

This study presents an approach to optimizing the output power in a magnetically geared generator by employing subdomain modeling and particle swarm optimization. Accordingly, the subdomain analytical method is utilized to obtain the induced voltage, inductance which are used to predict output power. Afterward, the swarm intelligence optimization technique is applied to reach the maximum output power point. The 12/17/15 prototype evaluated the proposed model by comparing the calculated results and finite element method simulation.

This study proposes an innovative approach that integrates the subdomain method with sequential quadratic programming (SQP) to optimize the volume of a high-speed surface-mounted permanent magnet synchronous motor in an air compressor operating at 110 000 rpm. Unlike conventional optimization tools that often rely on finite element analysis (FEA) software, by leveraging the subdomain method for electromagnetic modeling, we obtain an analytical solution that rapidly represents the behaviors of the motor. Subsequently, the SQP technique is applied to optimize the volume of the model while satisfying design constraints. The proposed model is verified by FEA simulation.

This study presents an approach for calculating the stress and deformation increase in the modulation of magnetically geared machines using a mathematical method. An analytical method is employed to obtain the magnetic force density acting on the modulation components. Afterward, the proposed mathematical method predicts the mechanical characteristics. The 9 slots/32 poles/19 modulations model was evaluated via a comparison with the finite element method simulation.

This study presents an approach to calculating the temperature increase in the internal components of permanent magnet synchronous machines by applying lumped-parameter thermal networks and analytical methods. Accordingly, the thermal equivalent circuit method is employed to obtain the temperatures of the machine’s internal components. Furthermore, this analytical method predicts the temperature distribution in the slot area. The 24/6 prototype was used to evaluate the proposed model by comparing the calculated and finite element method simulation.

Abstract Background Multidetector computed tomography (MDCT) angiography is a useful examination to detect the source of the bleeding in patients with hemoptysis. The aim of the study was to prospectively evaluate the role and clinical efficacy of MDCT angiography before bronchial artery embolization (BAE) for the management of hemoptysis, and to investigate the predictors of early recurrence. Methods It is a double-center study which included 57 hemoptysis patients undergoing MDCT angiography prior to BAE from August 2019 to July 2020. A prospective analysis of culprit arteries detected by MDCT angiography allowed an evaluation of the role of this technique. A follow-up was done to assess the efficacy of BAE with preprocedural MDCT angiography and to explore the risk factors of early recurrent hemoptysis. Results The accuracy of MDCT angiography in the identification of culprit arteries was as high as 97.5%. The average number of total culprit arteries per patient was 2.75 ± 1.73. Among which, the average numbers of culprit ectopic bronchial arteries (BAs) and non-bronchial systemic arteries (NBSAs) per patient were 0.21 ± 0.41 and 1.04 ± 1.57, respectively. The immediate clinical success rate, total hemoptysis recurrence rate, and early hemoptysis recurrence rate of BAE following MDCT angiography were 94.7, 18.5, 16.7%, respectively. Aspergilloma (HR = 6.63, 95% CI: 1.31–33.60, p = 0.022) was associated with an increase in the risk of early recurrence. Conclusions MDCT angiography should be performed before BAE for the management of hemoptysis. Aspergilloma was an independent predictor for early recurrence.

Montmorillonite (MMT), a natural clay mineral with high ion-exchange capacity and trace metal adsorbability, has been demonstrated to be a suitable binding phase in the diffusive gradient in thin film (DGT) technique for the determination of labile trace metals in synthetic water samples. However, in situ working performance of DGT-MMT with natural river water has not yet been investigated. The present study examined the performance of a DGT containing montmorillonite (MMT) for the in situ isolation and determination of labile Cd, Pb, Mn, and Zn fractions in Lach Tray River water, North Vietnam. The repeatability and accuracy of the DGT-MMT probe were assessed on the basis of seven measurement replicates performed on Cd2+, Pb2+, Mn2+, and Zn2+ standard solutions. Then, the DGT-MMT probes were deployed in Lach Tray River water at different sampling sites to determine the labile metal fractions present in river water. By comparing the total and dissolved metal concentrations in the river water, the distributions of the four tested trace metals were constructed. The proportions of the dissolved fractions of Cd, Pb, Mn, and Zn were 46.7–73.7%, 38.5–63.9%, 36.4–41.6%, and 49.8–67.7%, respectively. The results also showed that the high accuracy and reproducibility of the DGT-MMT data were comparable with measurements obtained by the commonly used DGT-Chelex-100 method. In comparison with the data obtained from anodic stripping voltammetry (ASV), a traditional technique for the determination of non-in situ speciation of trace metals, labile metal concentrations measured by DGT-MMT were in similar ranges. These findings indicate that naturally available montmorillonite can be used as an alternative binding material in DGT probes for the in situ determination of labile metal concentrations in natural watercourses.

This paper focuses on proximity losses prediction in conductors of power electronics transformers. The method is based on the concept of equivalent complex permeability applied to rectangular conductors. A 1-D analytical model is analyzed. It has been shown that the 1-D model does not take into account edge effects. Two complementary approaches have been proposed. One treats scattered conductors; other deals with package of conductors. Both approaches are compared with a good accuracy and economic computation time. [ABSTRACT FROM AUTHOR]

This paper describes the route, from simulations toward experiments, for optimizing the magnetoelectric (ME) geometries for vortex magnetic field sensors. The research is performed on the base of the Metglas/Piezoelectric (PZT) laminates in both open and closed magnetic circuit (OMC and CMC) geometries with different widths (W), lengths (L), and diameters (D). Among these geometries, the CMC laminates demonstrate advantages not only in their magnetic flux distribution, but also in their sensitivity and in their independence of the position of the vortex center. In addition, the ME voltage signal is found to be enhanced by increasing the magnetostrictive volume fraction. Optimal issues are incorporated to realize a CMC-based ME double sandwich current sensor in the ring shape with D × W = 6 mm × 1.5 mm and four layers of Metglas. At the resonant frequency of 174.4 kHz, this sensor exhibits the record sensitivity of 5.426 V/A as compared to variety of devices such as the CMC ME sensor family, fluxgate, magnetoresistive, and Hall-effect-based devices. It opens a potential to commercialize a new generation of ME-based current and (or) vortex magnetic sensors. [ABSTRACT FROM AUTHOR]