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From the investigation regarding the dependence of power loss and electrical resistivity at a temperature at which crystalline anisotropic energy becomes zero, eddy current loss and residual loss could be obtained separately. The increase in residual loss as exciting magnetic flux density, Bm, follows Bm2 at 1 MHz and Bm3–4 at 100 kHz. This result shows that the residual loss arises from spin rotation inside the magnetic domain wall. The domain size was estimated to be in the region of 1–2 μm by applying the barlike domain-wall model to the eddy current loss obtained experimentally. The frequency of the spin rotation is estimated using the domain size, the thickness of the domain wall, and the exciting condition. The spin rotation inside the domain wall can reach the magnetic resonant frequency of Mn–Zn ferrites under the exciting condition of f>500 kHz and Bm>70  mT. This magnetic resonance occurring inside the domain wall is considered to generate the large residual loss.

The Ethiopian economy has grown significantly and the government has prioritized industrial skills development and expanded technical and vocational education and training (TVET). However, mismatches between the skills available and the skills required are widespread and the unemployment rate for TVET graduates is high. Little scholarly effort has been made to empirically identify the exact types and domains of skills in which these supply-demand mismatches happen. The present study relies on interviews with 30 vocational trainers, 19 employees, 13 factory managers and 3 garment industry experts. To measure the perception gaps between the supply and demand sides of worker skills and explain why mismatches occur, we conducted an assessment in which assessors from among the factory managers and vocational trainers along with the three industry experts concurrently graded the garment-manufacturing vocational skills of the same workers. For this purpose, we developed a unique instrument that captures the knowledge and skills of workers in real work environments. The analysis reveals that TVET trainers expect students to have comprehensive skills and grade the skills of workers more generously, whereas factory managers expect not variety but quality, and score workers' performance more critically. Differences in the educational backgrounds and practical experience of assessors contribute to these gaps. The evidence from this study suggests that the vocational skills assessment instrument we have developed for our research is valid and can serve as a basis for future large-scale performance assessments.

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