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The purpose of this paper is to verify results related to losses in the core of a brushless DC prototype motor, obtained using its computer FE models, by experimental tests on manufactured machines. The paper focuses on the comparison of losses in the core of a machine with a classical stator core made of an iron–silicon material (Fe–Si) and a new one made of a modern METGLAS material.

Computer models of the prototype motors were created using FEM. The designed machines were manufactured, and experimental tests were performed. To achieve high frequencies in rotating magnetic fields, motors with a stator to rotor pole ratio of 9/12 were built. Twin rotor approach was applied, as two identical rotors were built along the two geometrically identical stators made of different core materials.

Experimental studies have shown the superiority of the METGLAS material over the classical Fe–Si material. Material parameters were measured directly on the prepared cores as library data used in the simulation may be incorrect due to technological processes during core production, which was also verified. Problems related to twin rotor approach have been identified. Solution to the problem has been suggested. Necessity of 3D FEM modelling was identified.

The main source of originality is that METGLAS material used in the prototype machines was developed and manufactured by the authors themselves. Original approach to core parameter evaluation based on simplified methodology has been suggested. Another original part is a simplified methodology applied to loss measurement during no-load test.

This study aims to study the radar cross-section (RCS) of an intermeshing rotor with blade pitch.

The variation of rotor blade pitch is designed into three modes: fixed mode, linear mode and smooth mode. The dynamic process of two crossed rotors is simulated, where the instantaneous RCS is calculated by physical optics and physical theory of diffraction.

Increasing the pitch angle in the fixed mode can reduce the average RCS of rotor at the given head azimuth. The RCS curve of helicopter in linear mode and smooth mode will have a large peak in the side direction at the given moment. Although the blade pitch in smooth mode is generally larger than that in fixed mode, the smooth mode is conducive to reducing the peak and mean value of helicopter RCS at the given heading azimuth.

The calculation method for analyzing RCS of intermeshing rotor with variable blade pitch is established.

Global construction sector studies have significantly explored the impact of automation techniques, revealing their transformative potential. However, research on their application within specific local contexts, especially in developing countries like Nigeria, is sparse. Nigeria presents a unique context marked by challenges such as skilled labor shortage, safety concerns and cost efficiency. Therefore, investigating the implementation of automation techniques in the Nigerian construction industry is crucial to address these challenges, bring transformative advancements and contribute to a more balanced global discourse on automation adoption. This study aims to fill this significant research gap.

A mixed research method was deployed which combined both qualitative and quantitative data collection and analysis. Two focus group discussions conducted with 23 experts from both industry and academic institutions (qualitative) yielded 17 drivers which were used to formulate a well-structured questionnaire (quantitative), which was disseminated to construction professionals. Collected data underwent analysis through various statistical techniques, including percentages, frequencies, mean item scores and exploratory factor analysis.

Principal component analysis (PCA) yielded four driver clusters namely: (1) performance-related drivers, (2) visualization and efficiency-related drivers, (3) technological and human-related drivers and (4) economic-related drivers.

The study provides empirical insights that can aid stakeholders, decision-makers, policymakers and the government in formulating strategies to promote automation techniques in the Nigerian construction industry and beyond.

This study's originality lies in its exploration of the untapped potential of automation techniques in the Nigerian construction industry, offering novel perspectives on how these technologies can address specific challenges such as skilled labor shortage, safety concerns and cost efficiency, thereby paving the way for transformative advancements in the sector.