Contribution/ OriginalityThis study contributes in the existing literature on the renewable sources of energy in Nigeria by investigating the vast renewable energy resources and potentials in the country and suggested methods to improve energy generation for sustainable development.

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An inverted pendulum is a multivariable, unstable, nonlinear system that is used as a yardstick in control engineering laboratories to study, verify and confirm innovative control techniques. To implement a simple control algorithm, achieve upright stabilization and precise tracking control under external disturbances constitutes a serious challenge. Observer-based linear quadratic regulator (LQR) controller and linear matrix inequality (LMI) are proposed for the upright stabilization of the system. Simulation studies are performed using step input magnitude, and the results are analyzed. Time response specifications, integral square error (ISE), integral absolute error (IAE) and mean absolute error (MAE) were employed to investigate the performances of the proposed controllers. Based on the comparative analysis, the upright stabilization of the pendulum was achieved within the shortest possible time with both controllers however, the LMI controller exhibits better performances in both stabilization and robustness. Moreover, the LMI control scheme is effective and simple.

As the amount of data and information received and sent electronically increases in various Small and Medium Enterprises, companies and organizations, the adoption of cloud Database as a Service is becoming popular in the global business community. The operational burden encountered by users of Traditional Database Systems (TDS), such as configuration, provisioning, performance tuning, scalability, privacy and security, backup and access control, are transferred by Database as a Service to the service provider/operator. This offers lower hardware and software costs, remote online access to databases and reliable applications. Despite all the benefits of Database as a Service, security and privacy issues of the cloud database can present significant challenges. With the increase of unauthorized access to confidential data in the cloud, this paper presents encryption techniques that provide strong security against attacks using Transparent Data Encryption (TDE). To protect the confidentiality of the cloud database, TDE is used to transparently encrypt and protect data at rest, on hard disk, in transit and on backup media. TDE is effective, easy and provides high security levels to columns, tables and table space for data that require protection. This paper studies the performance of encryption algorithms (AES128, AES192, AES256 and 3DES168) with regard to CPU time, execution time and elapsed time. AES128 is found to have a better performance than other encryption algorithms.

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