Journal of Measurements in Engineering

Journal of Measurements in Engineering, (in Press).Yaoheng Li, Jinbao Zhang, Hui Wang, Jinle Zhang, Haiquan Zhang, Fuqiang ZhaoA reliability evaluation method for SiC MOSFET components based on the nonlinear Wiener process is proposed using small-sample threshold voltage degradation data under multiple operating conditions. In this method, the exponential function and power function are respectively used to characterize the influences of influencing factor parameters and time effects on the drift coefficient, thereby establishing a mathematical model capable of describing the degradation behavior of SiC MOSFET components. Based on the threshold voltage degradation data of 35 SiC MOSFET component samples, Limited-memory Broyden-Fletcher-Goldfarb-Shanno with Bound constraints (L-BFGS-B) is employed for parameter estimation. Meanwhile, the Bootstrap method is adopted to quantify the uncertainties of the initial degradation amount and influencing factor parameters under small-sample conditions. Through the Monte Carlo simulation method, the reliability evaluation of SiC MOSFET components is conducted under the designed operating conditions, and accurate reliability evaluation results, as well as their confidence intervals are obtained. The results demonstrate that the proposed nonlinear Wiener process model can effectively capture the degradation characteristics of SiC MOSFET components under different operating conditions, providing a scientific basis for further reliability evaluation and life prediction of power electronic equipment.

Journal of Measurements in Engineering, (in Press).Changbo Lin, Xiaoyu Guo, Enyong Xu, Lidong Liang, Zhenzhen JinAs a critical component of the automotive powertrain system, the performance status of electric motors directly impacts vehicle operational safety. During vehicle operation, sensor signals are frequently subject to noise interference, while motors typically operate under varying conditions, posing significant challenges for fault diagnosis. To address these issues, this paper proposes a cross-domain fault diagnosis method based on attention-guided graph convolutional networks, effectively countering interference from variable operating conditions. First, to tackle noise in extracted signal data, time-frequency domain feature fusion is employed to capture signal characteristics from both temporal and spectral perspectives, comprehensively extracting useful information. Subsequently, a wavelet kernel convolution layer is introduced, leveraging the multi-resolution properties of wavelet transforms to enhance feature extraction capabilities. Second, a graph-generation structure based on attention mechanisms is employed. This structure combines autoregressive moving average filter graph convolutions with multi-order graph convolutions based on Chebyshev polynomials to achieve further feature extraction and capture multi-scale information. Finally, the advancement of this method has been verified through a series of experimental cases, which demonstrates superior performance compared to other models across various cross-domain tasks.

Journal of Measurements in Engineering, (in Press).Wei Li, Youcai Cao, Yuanhao Li, Quan Wang, Yali Wang, Jian Yang, Yiwei JiaoExpansive, collapsible saline soils – widespread across northwestern China – are especially susceptible to desiccation-driven shrinkage, which progressively degrades soil fabric and triggers structural damage. Here we evaluate whether water-soluble polyacrylamide (PAM) can simultaneously enhance water retention and mechanical integrity in such soils. Using Atterberg-limit characterisation, indirect tensile testing, disintegration assays and desiccation – shrinkage experiments, we show that increasing PAM concentration consistently raises the liquid limit and plasticity index, whereas the plastic limit remains largely unchanged. Both shrinkage resistance and tensile capacity exhibit a clear optimum at 0.8 % PAM, where the shrinkage limit is maximised and tensile strength reaches its peak. In agreement with these macroscopic gains, PAM substantially delays disintegration and prolongs the time to complete dispersion, indicating improved stability upon wetting. Throughout drying – spanning rapid, falling-rate and constant-rate evaporation regimes – PAM-treated soils lose water markedly more slowly, demonstrating a robust improvement in water-holding capacity. We attribute these enhancements to hydrogen bonding between amide functionalities and water molecules, polymer-chain entanglement that promotes interparticle bridging, and a reduction in particle-surface electrokinetic (zeta) potential that stabilises the soil fabric.

Journal of Measurements in Engineering, (in Press).Jianhua LiuTo enhance the convenience of measuring unbalanced vibrations in rotating equipment and meet the on-site operation and maintenance requirements, a portable vibration and dynamic balance measurement system was designed and tested. The system, with the STM32F407VGT6 chip as its core, mainly consists of data detection module, data processing and transmission module, and terminal control and display module. The data detection module includes photoelectric sensors and vibration sensors. The data processing and transmission module incorporates optocoupler isolation, A/D conversion, and multiple communication modules. The terminal control and display module enables human-computer interaction and remote management. In terms of hardware design, circuits such as tracking band-pass filters and programmable gain amplifiers were developed to optimize signal acquisition quality. At the software level, fundamental frequency extraction algorithms including DFT were integrated to ensure accurate extraction of vibration characteristics. Experimental verification shows that the system can achieve high-precision acquisition of vibration signals and calculation of unbalance within the rotational speed range of 0-3000 rpm. The coincidence degree of fundamental frequency extraction results between the STM32 hardware terminal and the MATLAB software terminal exceeds 95 %, and data interaction and remote monitoring can be accomplished through multiple communication methods. This system meets the requirements of on-site portable operation and maintenance, providing reliable technical support for dynamic balance correction of rotating machinery.

Journal of Measurements in Engineering, (in Press).Fangcai Zhu, Haijie Wen, Zengjie Liu, Jiang Guo, Xuebin XieTwo types of rock specimens simulating grout curtains were prepared: one featuring solely an axial through-hole and the other featuring combined axial and transverse holes (termed combined-hole specimens). Coupled permeability-damage tests under cyclic loading-unloading were conducted to analyze the effects of peak stress level, confining pressure, seepage pressure difference, and defect geometry (curtain filling configuration) on permeability evolution and damage accumulation. The results indicate that: (1) Peak stress level is the primary factor governing damage development rate; (2) Higher confining pressure mitigates damage in the surrounding rock and decelerates permeability increase; (3) Larger seepage pressure difference (≥ 0.5 MPa) significantly enhances the stability and accuracy of permeability measurements; (4) For combined-hole configurations, increasing the transverse hole area (and thus the grout volume) provides more lateral seepage paths, effectively reducing axial permeability by up to two orders of magnitude. This study provides an experimental framework for assessing the long-term sealing performance of grouted curtains under repeated dynamic loading akin to blasting disturbances.