e‐Maintenance Framework for Strategic Asset Management in Tertiary Institutions

Tertiary institutions require buildings such as its senate building, classrooms, laboratories, administrative rooms, hostels and other offices in order to function. Providing and maintaining these buildings require a lot of planning and capital investment. The study examined the prospects of using e‐ Maintenance platform for strategic asset management in tertiary institutions. This study noted that adequate maintenance of the building infrastructural base of tertiary institutions is crucial for sustainability in the face of dwindling funds in the education sector. In order to automate the e‐ Maintenance process for strategic maintenance of the institution’s building maintenance, a use case diagram, system block diagram, sequence diagram and activity diagram were designed and presented in this study. Three (3) main users are essential in the sequence of operation of the e‐Maintenance platform. These users represent the building occupants, the facility manager and the management personnel; for effective oversite and performance monitoring. The methodology of this research includes using the combination of HTML, CSS and the C‐Sharp programming language for the interface design and server side scripting while MySQL was the database platform used for storing and retrieving the data used for the application. In conclusion, the study developed an e‐Maintenance framework for strategic asset management in tertiary institutions. Keywords Asset management Automation Construction industr

Effect of temperature on specific retention volumes of selected volatile organic compounds using the gas-liquid chromatographic technique revisited

This paper is a continuation of our interest in the influence of temperature on specific retention volumes and the resulting infinite dilution activity coefficients. This has a direct effect in the design of absorption and stripping columns for the abatement of volatile organic compounds. The interaction of 13 volatile organic compounds (VOCs) with polydimethylsiloxane (PDMS) at varying temperatures was studied by gas liquid chromatography (GLC). Infinite dilution activity coefficients and specific retention volumes obtained in this study were found to be in agreement with those obtained from static headspace and group contribution methods by the authors as well as literature values for similar systems. Temperature variation also allows for transport calculations for different seasons. The results of this work confirm that PDMS is well suited for the scrubbing of VOCs from waste gas streams

Effect of oxygen and micro-cracking on the flotation of low grade nickel sulphide ore

This study investigated the effect of oxygen and micro-cracking on the flotation of low grade nickel sulphide ore. The ore treated contained serpentine minerals which have a history of being difficult to process efficiently. The use of oxygen as a bubbling gas has been noted to be effective because it increases the pulp potential. The desired effect of micro cracking the ore is that the nickel sulphide minerals will become activated and this activation will render these minerals more susceptible to react with potassium amyl xanthate collectors, resulting in a higher recovery of nickel and hinder the recovery of other undesired minerals contained in the ore. Higher nickel recoveries were obtained when pure oxygen was used as a bubbling gas rather than the conventional air. Microwave cracking favored the recovery of nickel

Improving Employability Skills Through a Web-Based Work Integrated Learning Database for Construction Students

Employability and Unemployment continues to be dire issues that Nigerian youth are faced with daily in a saturated employment market. Whereas, the use of workintegrated learning can help bridge the gap by increasing employability skills among students. The study examined the benefits of having a work-integrated learning (WIL) program for students in the construction field. Therefore, the study developed a framework for improving employability skills through a web-based work integrated learning database for construction students. Using a system block diagram, use case diagram and activity diagram, the study illustrated the functional requirement needed for the development of the WIL platform. The WIL platform is a web-based system pooling submission of available WIL positions from employers in construction businesses and former WIL students in order for prospective WIL students to access possible openings where they can learn in a workplace environment. The methodology of this research includes using the combination of HTML, CSS and the C-Sharp programming language for the interface design and server side scripting while MySQL was the database platform used for storing and retrieving the data used for the application. In conclusion, the study designed a WIL platform for construction students. The use of the WIL platform is intended to encourage employability of construction students by ensuring that they are adequately engaged in a work place training

Thin Layer Drying Kinetics and Modelling of Okra (Abelmoschus Esculentus (L.) Moench) Slices under Natural and Forced Convective Air Drying

The effect of sample thickness (10 and 20 mm), method of drying (open sun, solar and hot air drying) and drying air temperature (50, 60 and 70 oC) on the drying characteristics and kinetics of okra slices were investigated. The results showed that sample thickness, method of drying and drying air temperature significantly (P = 0.05) affected the drying rate and thus the drying time. It was observed that okra slices would dry perfectly within 216 – 240 h, 192 -216 h, and 12 – 19 h under open sun, solar and hot air drying, respectively. Irrespective of the drying method, all the samples dried in the falling rate period with no constant rate period. Four thin-layer semi-empirical mathematical drying models (Newton, Page, Henderson and Pabis, and Logarithmic models) were fitted to the experimental drying curves. The models were compared using the coefficient of determination ( ) and the root mean square error (RMSE). The logarithmic model has shown a better fit to the experimental data obtained from the open sun, solar and hot air drying respectively as relatively compared to other tested models. Correlation between the model parameters and the drying air temperature (under hot air drying) to calculate moisture ratio in relation to the drying time were also determined. The transport of water during drying was described by application of Fick’s diffusion model and the effective moisture diffusivity was estimated. The value ranges from 0.253 to 0.901 × 10-10 m2/s for open sun, 0.31 to 1.01 × 10-10 m2/s for solar drying and 3.29 to 14.7 × 10-10 m2/s for hot air drying, respectively. The Arrhenius-type relationship describes the temperature dependence of effective moisture diffusivity and was determined to be 16.74 kJ/mol and 10.39 kJ/mol for 10 and 20 mm sample sizes, respectively. Keywords: Okra; Open sun drying; Solar drying; Hot air drying; Mathematical modelling; Effective moisture diffusivity.

Mathematical Modelling and Simulation of the Mass and Heat Transfer of Batch Convective Air Drying of Tropical Fruits

In the present study, a mathematical model capable of predicting the instantaneous moisture and temperature distribution inside fruit and vegetable material undergoing shrinkage during drying process has been developed. The model takes into account moisture content and shrinkage of material as well as shrinkage dependent effective diffusivity. The mass transfer and heat equations were solved using a numerical technique. For evaluation and validation purposes, the model was applied to drying data obtained from the drying tests carried out on banana slices. An oven dryer was used to conduct the test. Banana slices of approximately 5 mm thickness and 30 mm diameter were dried over a temperature range of 50 oC and 70 oC for 6 hours. The predicted results compared favourably with the experimental results. Thus, the experimental results validated the model developed. In addition, empirical drying rate equations are developed. The model is therefore capable of predicting dynamic behaviour of drying of fruits undergoing shrinkage and, as such, it can be used as a design tool. Keywords: Drying; Mathematical modelling; Shrinkage; Simulation; Moisture diffusivit

Work Facets Predicting Overall Job Satisfaction among Teachers in Selected Secondary schools in Ibadan South-West Nigeria: A Minnesota Satisfaction Questionnaire Survey

Background: Global measures are often used to assess employees’ job satisfaction. However, important information is lost when this approach is  adopted. The use of multidimensional approach provides robust information for potential intervention. This study aimed to assess the work facets  predicting the overall single-item job satisfaction measure among teachers in Ibadan, Nigeria. Methods: This was a cross-sectional descriptive study conducted among 476 secondary school teachers selected using a multistage sampling  method. A structured questionnaire was used for data collection while data was analyzed using SPSS version 26. The Minnesota Satisfaction  Questionnaire (MSQ) and a single-item satisfaction measure assessed satisfaction. A linear regression model of the overall job satisfaction was developed. P-value ≤ 0.05 was regarded as statistically significant. Results: The mean age of respondents was 38.1±9.0 years. Majority of respondents were females 263 (55.3%) and married 363 (76.3%). The  respondents expressed above average satisfaction with all work facets except compensation 161 (33.8%) and work conditions 223 (46.8%). The work  facets which significantly predicted overall job satisfaction included: supervision-human relations (β = 0.121: 95% CI = 0.013 to 0.229; p = 0.028);policies & practices (β = 0.111: 95% CI = 0.021 to 0.201; p = 0.016); compensation (β =0.125: 95% CI = 0.035 to 0.214; p = 0.006) and recognition (β = 0.113: 95% CI = 0.006 to 0.220; p = 0.039) Conclusion: Overall job satisfaction was mostly predicted by factors extrinsic to the job, so these could be specifically targeted for interventions to  improve job satisfaction among teachers