International Journal of Engineering Research in Africa Vol. 43

Abstract: Hydrogen is likely to play a significant role in the concept of low-carbon power generation in support to renewable energy systems. It is abundant, eco-friendly, highly efficient and have the potential to be more cost-effective than fossil fuels provided that the engineering challenges associated with its safe infrastructure development, economical extraction and storage are solved. Presently, about 50 million metric tons of hydrogen is generated on a yearly basis, most of that is used for oil refining and ammoniac production. Other applications include electric vehicles, power to gas and power generation, etc. This study focuses on the use of hydrogen for power generation. The main goal is to investigate technical and economic performances of a renewable hydrogen-based energy system as an alternative to diesel generators for powering a remote telecoms base station. The proposed energy system consists of a photovoltaic generator, an electrolyser, a fuel cell, a hydrogen tank, a battery storage system and a power-conditioning unit. The system is simulated using Homer Pro software.

Abstract: Maintenance optimization is applied by organizations to develop robust maintenance programs while attempting to establish a trade-off between competing maintenance requirements and resources. For this reason, maintenance decisions derived from maintenance optimization models are adversely affected, if (a) the maintenance objective(s) applied as input to the optimization models is not dynamically reviewed as the organizations environment context changes, and (b) there is continued use of historical maintenance objectives, oftentimes the practice for organizations lacking a framework for selecting maintenance objectives (MO’s). To address this, an interactive maintenance objective selection framework for stakeholders that aligns with and considers changes in the organization’s business, operational, and technical context, where dynamic maintenance objectives are selected and prioritized for application in real-life maintenance optimization models is proposed. The framework uses an analytic network process (ANP) based methodology, for selecting the relevant MO’s in view of competing dynamic criteria, for instance, employing remanufactured spares to optimize availability and maintenance cost. The applicability of the framework is demonstrated in case studies of companies operating in diverse industries like aviation and manufacturing in Africa. The study highlights the effects of dependencies between competing maintenance objectives, where the dependencies invariably influence how organizations prioritize MO’s to use for maintenance optimization programs. The additional value of the proposed framework lies in assisting organizations select maintenance objectives applicable to the organization while considering competing objectives and evolving business context.

Abstract: In the present condition, customer demand has increased gradually due to technological development and globalisation in this world. So this made the industrialist to deliver the products at right quantity at right place at right time with shorter lead time. But due to high rejection rate the industries fails to meet the customer demand which in turn reduces the customer satisfaction. Hence, this research an attempt was made to reduce the defects of casting components in an original equipment manufacturer. The study was carried out in a foundry of brake drum manufacturing industry. The problem was inside that the industry could not meet the customer demand due to high rejection rate and the major contributor for high rejection is found to be sand drop. Hence, proposed solutions have been implemented to achieve the objectives. After implementation of proper lean tools it was observed from the results that, the rejection rate was reduced by about 4% and the quality level was increased by about 4.4%.

Abstract: Evolving structures and systems in higher education institutions require leaders who can provide direction, implement plans, and motivate people towards greater performance that meets or surpasses organizational goals. The authors in this study sought to ascertain the relationship between leadership styles and job performance among academic staff working in three (3) selected private universities in Ghana. A sample size of 114 was drawn from a total population size of 160 staff from Data Link Institute, Fountainhead University College and Presbyterian University College. Stratified random sampling method was used to gather data from respondents. Using three different hypotheses that were stated and tested with linear regression and Pearson’s Product Moment Correlation, the study revealed that leadership styles have direct effect on job performance. In particular, democratic leadership style showed a significant impact on the employee’s performance while autocratic and laissez-faire leadership styles demonstrated less or no significant impact on the employee performance. The authors proceed to discuss the implications of the study by way theory, practice and future study. Additionally, we recommended among other things that the use of autocratic and laissez-faire leadership styles should be reduced in practice since they have the proclivity of stifling the overall organization performance.

Abstract: The objective of this study was to assess the adoption level of Total Quality Management (TQM) in pharmaceutical manufacturing industry in Southwestern Nigeria by a cross-sectional survey of staff in Lagos, Ogun and Oyo States of Nigeria involving 348 of the 2,649 members, selected by multi-stage sampling. Primary data were collected using a set of pre-tested semi-structured questionnaire which sought to elicit information on the level of TQM adoption and designed with items on a Likert–type scale of seven alternative responses with weighting scores of 0 through 6, representing seven stages (levels) in the adoption process. Adoption was taken as becoming effective from the sixth stage (level 5). Factors influencing TQM adoption were identified by employing a Likert-type influence scale with five alternative responses and weighting scores of 0 - 4. Weighted averages (WA) and means of weighted averages (MWA) were employed in summarising the data while t-test and regression analyses were used in identifying significant relationships between variables at 5% significance level. The results showed that TQM adoption was at implementation (trial) level (MWA ≈ 4) and had not become actualised in the industry (t = 11.906, df = 3, p = .000). The study concluded that the adoption level of TQM in this industry was at trial level and TQM adoption was ineffective. Thus, there is need for improved adoption of the various components of TQM, particularly ‘leadership commitment’ and this can be achieved through sustained TQM training and advocacy by professional associations within the industry such as Nigerian Association of Industrial Pharmacists (NAIP) and Pharmaceutical Society of Nigeria (PSN).