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This paper proposes a detection method of open-circuit fault of insulated-gate bipolar transistor in the voltage source inverters. The magnetic field signal at the DC bus of the inverter is collected and analysed to detect the fault. First, the simulation is developed for a voltage source inverter-fed induction machine drive which operates in healthy state and single switch open-circuit conditions. The faulty characteristic frequencies in the spectrum of DC-link current signal are derived on the basis of the power balance analysis through the inverter. Second, laboratory tests are implemented with a test bed of voltage source inverter-based induction machine drive in which a Hall sensor suited for the geometry complexity of the DC bus structure is utilized for measuring the magnetic field signal, which can be considered as an image of the simulated DC-link current. The fast Fourier transform of the magnetic field signal shows sharp increases in spectrum amplitude at the fundamental, second-order and third-order harmonics that they can be used as the indication to detect the fault. The approach using proposed signal offers several advantages such as single-sensor requirement, non-invasive and less costly device. [ABSTRACT FROM AUTHOR]

The under-representation of several ethnic groups in existing genetic databases and studies have undermined our understanding of the genetic variations and associated traits or diseases in many populations. Cost and technology limitations remain the challenges in performing large-scale genome sequencing projects in many developing countries, including Vietnam. As one of the most rapidly adopted genetic tests, non-invasive prenatal testing (NIPT) data offers an alternative untapped resource for genetic studies. Here we performed a large-scale genomic analysis of 2683 pregnant Vietnamese women using their NIPT data and identified a comprehensive set of 8,054,515 single-nucleotide polymorphisms, among which 8.2% were new to the Vietnamese population. Our study also revealed 24,487 disease-associated genetic variants and their allele frequency distribution, especially 5 pathogenic variants for prevalent genetic disorders in Vietnam. We also observed major discrepancies in the allele frequency distribution of disease-associated genetic variants between the Vietnamese and other populations, thus highlighting a need for genome-wide association studies dedicated to the Vietnamese population. The resulted database of Vietnamese genetic variants, their allele frequency distribution, and their associated diseases presents a valuable resource for future genetic studies. [ABSTRACT FROM AUTHOR]