A rapidly growing demand and shortage of electric energy require mankind to efficiently use it, recuperate and store it from the existing system, when possible, for further applications whenever the need arises. Electric trains figure among big energy consumers and among different railway transportation services; light rail transit trains are characterized by frequent stoppings to entrain and detrain passengers. In their operation, traction drives are made to keep on braking in order to meet their service requirements between closely spaced passenger stations. The modern service braking system used is regenerative braking, which acts as an electric energy generator during the braking period. The objective of this paper is to estimate the magnitude of regenerative energy that can be recuperated as a percentage of train energy consumption on East-West (Ayat to Tolhailoch) and West-East (Tolhailoch-Ayat) directions of Addis Ababa Light Rail Transit. Mathematical equations have been used to calculate the energy consumed between stations followed by the quantification of regenerative energy at each passenger station. Considering the current average running speed (24km/h) of the line, it resulted that 26.31% and 28.18% of energy consumption for East-West and West-East directions respectively are saved through regenerative braking energy recuperation. From the above results, it was observed that the magnitude of regenerative energy strongly depends on the speed at which the train is running and the efficiencies of inverter and traction induction motor.

The desire for earthquake hazard mitigation has been the focus of many researchers and governments for decades. This is paramount because an earthquake disaster can quickly cause many injuries, fatalities, and damages. The global database of the 21,000 most devastating disasters (earthquakes included) since 1900 indicates that 50% of them with the most significant number of injuries occurred only during the past 20 years. In human history, the Xaanxi earthquake is ranked third among the disasters that claimed more lives. In addition, earthquakes contributed to six of the most deadly disasters of the past two decades and 21% of the economic losses. In the same period, the earthquakes due to the Virunga volcanic activity were responsible for more than 100 deaths and extensive material and infrastructure damage. The referenced information and statistical data about the earthquake occurrence process, adverse effects, economic losses, and the current technological success in reducing its risks through warning systems are the basis for developing this paper. The authors aim to raise awareness and recommend that the Virunga region countries (Democratic Republic of the Congo, Rwanda, and Uganda) be a good place for an Earthquake Early Warning System and Earthquake Management Plan. An Earthquake Early Warning System even caught the attention of the United Nations, where the endorsed Sendai Framework for Disaster Risk Reduction (UNISDR, 2015) specified that early warning must be a priority and has to be substantially evolved by 2030.

Healthy population is regarded as the most valuable asset of any country. Unfortunately, the health challenges that hinder mankind's wellbeing are enormously increasing. Examples include but are not limited to: the diversity of emerging diseases afflicting the global population, the projected demographic growth of elderly people who need consistent monitoring, the deficiency in medical staff, the lower density of physicians, and the challenging geographical location of the population from healthcare providers. The mitigation of such health challenges calls for novel technologies to improve patient outcomes. In this article, seven emerging technologies, namely: Wearable Devices and Internet of Things, Artificial Intelligence, Blockchain Technology or Distributed Ledger Technology, Robotics Technology, Telehealth and Telemedicine, Big Data Technology and Nanomedicine have been highlighted. For each discussed technology, its historical background, development drivers, market status and trends, significance to healthcare, key player companies, and associated challenges have been presented. The information contained in this paper was collected from different journal articles, websites, reports, conference proceedings, and books. It was observed that though the technologies discussed in this article show growth at different rates, healthcare technology development and implementation are very promising in revolutionizing the health sector and improving the health of the population. Therefore, healthcare providers and countries are recommended to put in place Healthcare Technology Assessment Programs to help them collect data regarding the technology efficacy, relevance, safety, outcomes, and alternative technologies towards better planning for healthcare services improvement.