Coronavirus Disease 2019 (COVID-19) spreads rapidly and is easily contracted by individuals who come near infected persons. With this nature and rapid spread of the contagion, different types of research have been conducted to investigate how non-pharmaceutical interventions can be employed to contain and prevent COVID-19. In this review, we analyzed the key elements of digital contact tracing strategies developed for the prevention and containment of the dreaded epidemic since its outbreak. We carried out a scoping review through relevant studies indexed in three databases, namely Google Scholar, PubMed, and ACM Digital Library. Using some carefully defined search terms, a total of 768 articles were identified. The review shows that 86.32% (n = 101) of the works focusing on contact tracing were published in 2020, suggesting there was an increased awareness that year, increased research efforts, and the fact that the pandemic was given a very high priority by most journals. We observed that many (47.86%, n = 56) of the studies were focused on design and implementation issues in the development of COVID-19 contact tracing systems. In addition, has been established that most of the studies were conducted in 41 countries and that contract tracing app development are characterized by some sensitive issues, including privacy-preserving and case-based referral characteristics.

Recommender systems (RSs) effectively curb information overload by providing personalized suggestions of items to users across different online domains. Their widespread use in e-commerce enhances user engagement, personalizes shopping experiences, and drives sales growth. However, despite the effectiveness of these systems at generating recommendations for users, they still raise major privacy and security concerns as their data could be exploited for malicious purposes, which can lead to data breaches and misuse. Therefore, this paper presents a comprehensive and systematic review of the underlying causes of privacy and security challenges in RS. It also provides a detailed taxonomy categorizing these concerns based on their targets and the risks they create. It further presents potential solutions that have been used in the literature while identifying challenges and possible research directions to pursue in a bid to address privacy and security concerns in RSs. This paper will be a useful resource for current and upcoming researchers in the domain of RSs. It will support knowledge advancement and steer appropriate research directions.

The continuous increase in human population across the world’s continents has given rise to the volume of waste generated. Improper waste management poses environmental and health risk, as such it is paramount to take meticulous measures to manage waste. Waste segregation facilitates the collection of recyclable materials and the safe disposal of non-recyclable ones. The manual method of waste segregation is unhygienic, costly, and time-consuming. This work proposes an Intelligent Waste Segregation System to cater for these setbacks. The proposed system integrates the working principle of inductive proximity, capacitive, and moisture sensors to identify and classify waste materials into metal, paper, plastic, and wet materials respectively while the Arduino microcontroller serves as the coordinating unit for all detection and classification activities. This way, the recyclable materials can be collected for further processing and the non-recyclable wastes can be disposed of in an environmentally friendly manner. The results of multiple tests of the developed system with the identified materials show 84.4% success rate, which makes it reliable for implementation in real-life systems. Deploying this solution in homes and industrial environments can foster resource optimization and hygienic waste management for environmental sustainability.

The need for energy conservation has become increasingly urgent in today's world, especially as energy costs continue to rise and the demand for sustainable living grows. For persons with physical disabilities, simple tasks like turning light switches on and off can be challenging, resulting in higher energy usage, increased electricity bills, and increased physical strain. Existing solutions often prioritize energy efficiency but overlook affordability and accessibility, making them impractical for low-income households. To address these issues, this paper proposes an affordable automated energy-saving lighting switch control system using Arduino Uno, ultrasonic sensors for human presence detection, and a relay to control lighting. A person-counter mechanism ensures accurate operation based on room occupancy. Experimental results shows that the proposed system achieves 100% accuracy in detecting human presence in a room, effectively reducing energy consumption from 0.4 kWh to 0.2 kWh per day, which corresponds to 50% energy savings. Additionally, it is 42.41% less expensive than the most affordable system compared in the paper. These findings underscore the system’s potential to offer an affordable, accessible, and energy-efficient solution that enhances the convenience and comfort of disabled persons while contributing to energy conservation efforts.

An examination is a means of assessing people’s knowledge, competence, or skills in a particular field. It can be through manual or physical contact or a computer-based approach. Achieving the purpose of high-standard examination can only be fulfilled when adequate measures are put in place and steps are taken to implement them. This study presents findings from the baseline study of security agents’ perspectives on conducting and administering examinations in Nigeria. The study adopted a survey approach that was based on the administration of a questionnaire which was carefully formulated to capture the views and opinions of the respondents on the available indices. The administered questionnaire was structured to curate information from the respondents about their knowledge of the stakeholders’ level of infractions and conformity with regulations. The survey attempted to know the extent of deterrent strategies against infractions and corrupt practices, the welfare packages available to security agents, and the examination bodies’ general performances, among others. Twenty thousand and two hundred (20,200) respondents across the six geopolitical zones of Nigeria from different categories of security agencies including the Federal Road Safety Commission (FRSC), Nigerian Civil Defense Corps (NCDC), Police Force, and private security outfits participated in the survey. The statistical-based analysis of data obtained from the survey revealed that the educational system has a competent workforce with a significant number of tertiary-educated individuals, a significant level of compliance of stakeholders to examination regulations, and effective enforcement of rules by security agencies. The analysis also revealed a substantial level of inadequacies with the operating environment and mechanisms for welfare and mobility packages as well as gaps in certain aspects of the examination process which may be connected to inefficient communication, logistical challenges and inadequate resources. The study justified the need for more attention to improving on the deterrent measures against examination misconduct through increased vigilance and addressing some factors that militate against the existing measures for curbing corrupt practices during the examination.