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A computational model for the heat generation and dissipation in a disk brake during braking and the following release period has been formulated. The model simulates the braking action by investigating the thermal behaviour occurring on the disc and pad surfaces during this period. A comparative study was made between grey cast iron (GCI), asbestos, Aluminium metal matrix composite (AMC), and aramid as brake pad and disc materials. The braking process and following release period were simulated for four material combinations, GCI disc and Asbestos pad, GCI disc and Aramid pad, AMC disc and Asbestos pad, AMC disc and Aramid pad using COMSOL Multiphysics software. The results show similarity in thermal behaviour at the contact surface for the asbestos and aramid brake pad materials with a temperature difference of 1.8 K after 10 seconds. For the brake disc materials, the thermal behaviour was close, with the highest temperature difference being 9.6 K. The GCI had a peak temperature of 489 K at 1.2 seconds and AMC was 465.5 K but cooling to 406.4 K at 10 seconds, while the GCI was 394.7 K.

This study presents the viabilities for power generation in Nigeria through the utilization of the sun's energy. Solar-thermal and photovoltaic options were discussed. It highlights the basic science for the design and selection of components for successfully harnessing solar power. Requirements for solar panel placement and orientation were also highlighted. It emphasizes that the knowledge and experience gained in solar energy as an abundant and convenient energy source, can play a role in steering the nation toward a permanent and sustainable development. The energy demand in Nigeria far outweighs the supply which is epileptic in nature. The acute electricity supply hinders the country's development notwithstanding the availability of vast natural resources in the country. Our ability to continue the trend for affordable energy will be severely tested in the coming decades, as evidenced by the widening trade imbalance, collapse of big manufacturing companies, sharp increase in the cost of doing business just to mention but a few. It is the issue of utilizing the sun's silent, inexhaustible, and non-polluting resource for power generation in Nigeria that this work addresses; hence it is the long-range review of the energy problem.

The rapid increase in global communication infrastructure in developing countries has drawn significant attention to the telecom sector. However, the dismal performance of the power sector in some countries like Nigeria poses a great challenge to the telecom industry which requires a reliable, efficient and environmentally friendly energy supply. Unstable electric grids, an erratic power supply, non-availability of trained and skilled personnel, and a prohibitive cost of site maintenance cumulatively have increased the need to harness abundant renewable energy sources, such as solar and wind. A comparative study of the viability of solar-diesel hybrid against diesel-only generator systems in powering a base station using the cost of kilowatt hour (kWh) self-generated electricity and levelised cost of energy (LCOE) was undertaken using data from some sites located in the Southwest (SW) and the Northeast (NE) regions of Nigeria. Homer Pro Software was used in data analysis. The results obtained showed that with a hybrid energy system (solar and diesel generator), there were 79% savings in fuel consumption, 83.2% savings in operation and maintenance cost for the hybrid energy system in the SW. The savings on fueling as a result of the use of hybrid systems was 86%, and the carbon footprint reduction was 76%. Furthermore, the cost of operation was reduced by 51% for Northeast. The LCOE for the solar hybrid system was determined to be $1.44 for NE1A and NE1B while that of NE2A was $1.46 and NE2B $1.47.

Health technology innovation in low- and middle-income countries (LMICs), including countries in Africa, falls far short of meeting the healthcare needs of these settings. The result is a heavy reliance on products and technologies imported from industrialised countries that are often not suited to, or sustainable for, LMICs. Appropriate healthcare products for LMICs are best developed in these countries, where local knowledge and understanding of needs, context and available resources may be incorporated into designs and implementation plans. The objectives for enabling health technology development in LMICs include: 1) expanding the base of expertise through research training programmes with a problem-solving focus; 2) stimulating new knowledge, approaches and solutions by enabling innovation; and 3) integrating research communities within and across institutions to build critical mass. The field of biomedical engineering is central to health technology innovation. This book is a response to the need for biomedical engineering capacity in Africa. It is grounded in the African context. It serves as a resource for academics and students in biomedical engineering, for those interested in entering the field in any capacity and for practitioners at every stage of product development. University leaders intent on establishing new biomedical engineering programmes or departments, may draw on the content for guidance on structuring their offerings. The book reaches beyond Africa, as it is relevant to other LMIC settings, and provides insights to guide global health initiatives focused on technology innovation.

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