The 57th volume of "International Journal of Engineering Research in Africa" are included peer-reviewed manuscripts reflecting the research results in the fields of materials science, applied and fluid mechanics, power engineering and power management, ecology safety and agriculture, communication, road construction, building materials, and geotechnical engineering. The presented scientific articles can be appreciated by the majority of engineers, academic teachers, and students majoring in the fields of engineering science.

This periodical edition includes peer-reviewed papers based on results of scientific research and engineering solutions in different areas of modern engineering science.

The 62nd issue of the journal includes articles that describe the latest research results in materials science, including alloys and composites, solar energy concentrator design, power electronic engineering, building materials and level service analysis in the trading company.

This periodical edition includes peer-reviewed papers based on results of scientific research and engineering solutions in different areas of modern engineering science.

We are glad to present the 35th volume of International Journal of Engineering Research in Africa. This volume contains articles describing the research results in the fields of materials science in the mechanical engineering, construction materials, technological processes in the chemical production, power distribution and engineering management. The articles will be useful for many engineers as well as for academic teachers and students majoring in these fields of engineering science.

This periodical edition includes peer-reviewed papers based on results of scientific research and engineering solutions in different areas of modern engineering science.

The 39th volume of International Journal of Engineering Research in Africa contains articles describing the research results in the fields of materials science, mechanical engineering, power engineering, construction materials and technologies, technological processes in the chemical production, planning and scheduling of production system. The articles will be useful for many engineers as well as for academic teachers and students majoring in these fields of engineering science.