We are glad to present our readers with the 40th volume of International Journal of Engineering Research in Africa. This volume contains articles describing the research results in the fields of materials science, mechanical engineering, power distribution and power control, construction materials and technologies, technological processes in the wastewater treatment and industrial engineering. The articles will be useful for many engineers as well as for academic teachers and students majoring in these fields of engineering science.

This volume of the journal represents the research results of properties and synthesis technologies for a multifunctional hydrogel material, concrete with aggregate from plastic waste, numerical modelling of natural convection processes in the elliptical cylinders, analysed the wastewater treatment technologies based on the use of natural chemicals and based on electroflotation and electrocoagulation. There are articles devoted to communication engineering, energy management in microgrids and potential assessment of wind energy in conditions of Ethiopia. The volume will be helpful to specialists in machinery, communication and construction, environmental protection and energetics.

Special topic volume with invited peer reviewed papers only.

This book is the proceeding of the International Conference on Sustainable Engineering Development and Technological Innovation (ICSEDTI 2022) that was successfully held on 11-13 October 2022 using an hybrid platform. The conference is themed “Sustainable empowerment of innovative solutions through the development of integrated scientific researches to enhance the advanced technological world”, which represents our belief of how the sustainability is essential in our approach to solve problems through technological innovation. A total of 56 papers were submitted and presented within the sessions of the conference. The papers’ topics revolve around Informatics Technology, Electrical Technology, Marine Technology, Manufacturing System and Technology, Mechanical Engineering, And also Information Industry and Management. In addition to the technical paper presentations, there were also five keynote speeches featured, and eight plenary talks were delivered. Two of the keynote speeches were delivered in person by Professor Selo from Universitas Gajah Mada, Indonesia, and Professor Goib Wiranto from the National Research and Innovation Agency, Indonesia. The rest of the keynote speeches were delivered online by Professor Yvon Kermarrec from IMT Atlantique, France; Professor Ian Gibson from University of Twente, Netherlands; and Dr. Ilham Akbar Habibie from The Association of Indonesian Engineer, Indonesia. It was a great pleasure to work with the technical program committee led by Mr. Hilfi Pardi, who have completed the imperative process of peer-review on the technical papers submitted in this conference. We are also very fortunate to have on our side the excellent organizing committee team of the Faculty of Engineering of UMRAH who work very hard to organize and support the conference. Finally, our appreciation to all the authors who have participated in this conference with their amazing achievements and enthusiasm. We firmly believe that ICSEDTI is a suitable platform for researchers, engineers, and developers who are concerned with sustainability in engineering and technological development. We hope in the coming years ICSEDTI will be better in terms of the organization of the conference, the quantity and the quality of the researches submitted, and most importantly the impact on the sustainability of technological innovation.

We present the 56th volume of the "International Journal of Engineering Research in Africa" to our readers. The collection contains the articles reflecting the research results in the fields of structural steel and alloys, development of composites, applied mechanics and mechanical engineering, experimental investigations of cement and concrete properties, assessment of the seismic resistance of structures, reliable preventive maintenance scheduling in power systems, cloud computing technology in Cloud of Things, evaluation of sustainable transportation system. The articles will be helpful for many engineers, academic teachers, and students majoring in the mentioned branches of engineering science.

The Conference Theme was: "Moving Africa forward through Engineering, Technology and Innovation". The conference brought together academics, researchers and industrialists from many disciplines, in particular those that have the most impact on Africa's Development. Most conferences on the continent have covered limited disciplines and therefore the opportunity has been lost sharing information, results and knowledge in a way which can solve the many contentious issues, most of which can be solved through a multidisciplinary approach.

The 3rd International Conference on Cloud Security Management (ICCSM-2015) invites researchers, practitioners and academics to present their research findings, works in progress, case studies and conceptual advances in areas of work where education and technology intersect. The conference brings together varied groups of people with different perspectives, experiences and knowledge in one location. It aims to help practitioners find ways of putting research into practice and researchers to gain an understanding of real-world problems, needs and aspirations.

Step-by-step procedures for planning, design, construction and operation: * Health and environment * Process improvements * Stormwater and combined sewer control and treatment * Effluent disposal and reuse * Biosolids disposal and reuse * On-site treatment and disposal of small flows * Wastewater treatment plants should be designed so that the effluent standards and reuse objectives, and biosolids regulations can be met with reasonable ease and cost. The design should incorporate flexibility for dealing with seasonal changes, as well as long-term changes in wastewater quality and future regulations. Good planning and design, therefore, must be based on five major steps: characterization of the raw wastewater quality and effluent, pre-design studies to develop alternative processes and selection of final process train, detailed design of the selected alternative, contraction, and operation and maintenance of the completed facility. Engineers, scientists, and financial analysts must utilize principles from a wide range of disciplines: engineering, chemistry, microbiology, geology, architecture, and economics to carry out the responsibilities of designing a wastewater treatment plant. The objective of this book is to present the technical and nontechnical issues that are most commonly addressed in the planning and design reports for wastewater treatment facilities prepared by practicing engineers. Topics discussed include facility planning, process description, process selection logic, mass balance calculations, design calculations, and concepts for equipment sizing. Theory, design, operation and maintenance, trouble shooting, equipment selection and specifications are integrated for each treatment process. Thus delineation of such information for use by students and practicing engineers is the main purpose of this book.

Virtual Reality is clearly interdisciplinary research. It has, not only Information Technology importance but social, educational, economical importance too. It combines multiple disciplines for the development of virtual reality systems in which the user has the immersive feeling of being in the real world. Virtual reality has several applications in almost all fields of real life. The most typical fields for the application of virtual reality are health-care, engineering and game industry. This book may be a solid basis for the novice and advanced engineers who would like to develop user friendly Virtual Environments for education, rehabilitation and other applications of Virtual Reality. Our book provides a resource for wide variety of people including academicians, designers, developers, educators, engineers, practitioners, researchers, and graduate students.