Table of Contents

Application of Structural Equation Modelling in Construction Industry

Research: Concept and Prospects

Abdullahi Yusuf Waziri,Mustapha Yakubu and  Muhammad Sa’adiya Ilyasu                         1-20

Enhancing Engineering Education through Problem – Based/ Student -Centred

Learning

 J.B. Otuu & I. Nnanna                                                                                                             21-34

Effects of Process Parameters on Mildsteel Corrosion Inhibition by Ethyl

Ester of Castor Seed Oil

Offurum, J.C.; Nwakaudu, M.S.; Ndukwe O.C. and Kamalu C.I.O.                                             35-45

Incessant and Unreliable Power Supply in Nigeria: Causes, Effects and Solution Ikorodu, Lagos State, Nigeria as a Case Study

Oshin, Ola Austin                                                                                                                    46-68

Performance of all Nigeria Banks’ Shares Using Student-T Mixture

Autoregressive Model

J. F. Ojo and R.O. Olanrewaju                                                                                                  69-82  

PERFORMANCE OF ALL NIGERIA BANKS’ SHARES USING STUDENT-T MIXTURE AUTOREGRESSIVE MODEL

J. F. Ojo and R.O. Olanrewaju

Department of Statistics,

University of Ibadan, Ibadan, Nigeria.

E-mail: jfunminiyiojo@yahoo.com,rasakiolawale@gmail.com

Abstract

This study attempts to model the all Nigeria banks’ volume of shares using the Student-t Mixture Autoregressive (TMAR) and the Mixture Autoregressive (MAR) models because the series has been characterized by fluctuation, excessive kurtosis and excessive skewness that was justified by the Degree of Freedom (DF)that was  greater than four, that is,in each regime of the TMAR model. The TMAR model substituted the Student-t Probability Density Function (PDF) for the error term in contrast to Gaussian used by MAR in order to cater for positive or negative excess kurtosis that might have distorted the parameters’ estimation in MAR. Though the stylized traits of the shape changing means, variances (volatilities), and conditional distributions of the two models were still maintained. The approach adopted the E-step and M-step (Expected and Maximization) iterative procedure in parameters’ estimation and detection of kurtosis whenever the DF is greater than four. The all Nigeria banks’ shares were fitted using TMAR and MAR models, the density function plot of all Nigeria banks’ shares between 4 January, 2007 and 20 April, 2015 revealed a 5-regime shift and the best model was recorded at MAR (5: 2, 1, 6, 2, 2) and TMAR (5: 2, 1, 6, 2, 2).  Apart from the fact that the standard errors of estimates from TMAR model were smaller compared to standard errors of estimates from MAR model, the TMAR model  out-performed the MAR model with minimum Akaike Information Criterion and Bayesian Information Criterion  of (438.98 and 454.54) and (445.84 and 459), respectively. In addition, the TMAR model recorded a lesser predictive error of Residual Mean Square Error (RSME) of 8.2960 compared to10.6061 recorded for MAR. Lastly, the banks’ shares recorded a rapid change and unpredictably higher volatility (risk) of 10.4370 for TMAR and 20.6902 for MAR in the third and fifth regimes compared to other three regimes with lesser risk.

INCESSANT AND UNRELIABLE POWER SUPPLY IN NIGERIA: CAUSES, EFFECTS AND SOLUTION IKORODU, LAGOS STATE, NIGERIA AS A CASE STUDY

Oshin, Ola Austin

Email: austinoshin@elizadeuniversity.edu.ng, zolaolaaustin@yahoo.com,

Abstract: The present unreliable and erratic power supply is a pointer to the fact that there is a great need for fault evaluation and reliability studies of electric power system in the Nigeria. The recent blackout in the country has grounded many activities and has destroyed many industrial processes. Also, the power industries face a lot of problems. Some of the highest priority issues being generation of sufficient power, urgent clearance of faults, adequate protection and increase reliability of the system,  that is, bringing a steady uninterrupted power supply to the consumers. The Nigerian power problem resulted to incessant planned, forced and unplanned outages. In addition, it has resulted to erratic and unreliable supply of electricity in the country. It has reduced productivity and has increased unemployment rate in the country to over 40million (this figure is over 70% of Nigerian youths. It has led many of the youths in the country to crime. It has led many of the deaths of many innocent people in the country.  Hence, an analytical method is developed to assess the dynamic- reliability of the distribution system, as well as optimizes the occurrence of faults along each of the individual consumer point in a feeder in order to improve the performance of the system. This research publication therefore evaluates the occurrence of faults which is about 856 occurrences during a period of 8 years and outages which range between 1118 to 3785 hours per annum along the distribution lines, also the failure rates of each of the feeders were analyzed in order to improve on the supply of electricity in the distribution network. The reliability of the system which ranges between 8.57*10^-12to 9.548*10^-5 were analyzed; and fault clearing techniques were carried out. Efforts were made to adequately assess the failure rates of the feeders which range between 0.003 and 0.001 and reliability of the distribution system. Efforts were also made to improve the performance of the system. As a result, it was possible to establish improvement techniques which ensure adequate and constant supply of electricity to all the consumers for industrial growth and employment: a basic solution to increasing crime rate in the country.

EFFECTS OF PROCESS PARAMETERS ON MILDSTEEL CORROSION INHIBITION BY ETHYL ESTER OF CASTOR SEED OIL

Offurum, J.C.; Nwakaudu, M.S.; Ndukwe O.C. and Kamalu C.I.O.

Department of Chemical Engineering,

Imo State Polytechnic, Umuagwo-Ohaji

Federal University of Technology, Owerri

Email: jullyengine@yahoo.com

Abstract: This research work was focused on the effects of process parameters on mildsteel corrosion inhibition by ethyl ester of castor seed oil. This was motivated by the necessity of creating a formidable alternative (through castor oil generation) to deal with the menace of corrosion in our industries, and to assess the sensitive factors that affect the corrosion process. Standard methods were employed during the oil generation and its subsequent performing ability enhancement through acid esterification. Corrosion study conducted at varying reaction conditions of concentration, temperature and dosage showed that corrosion rate increases in the direction of increased process parameters; the least value of the weight loss (2.3146g) was recorded at the lowest concentration (10g/L), temperature (40^oC) and Dosage (50% stroke), while the highest weight loss (37.1825g) was recorded at the highest concentration (20g/L), temperature (60^oC) and Dosage (70% stroke). Corrosion rate was also found to increase with time, and was more established in cases of blank conditions when compared with those with inhibitors. Generally, the castor seed oil was found to have ability of inhibiting mildsteel corrosion substantively, and as such is recommended for advanced chemical engineering applications.

Keyword: Effect, Process Parameter, Mildsteel, Corrosion Inhibition, Castor Seed Oil.

ENHANCING ENGINEERING EDUCATION THROUGH PROBLEM – BASED/ STUDENT -CENTRED LEARNING

                                                                                                                               J.B. Otuu & I. Nnanna

Department of Mechanical Engineering

Akanu Ibiam Federal Polytechnic, Unwana Afikpo, Ebonyi State

Email: johnotuu@gmail.com

ABSTRACT: The quality of engineering graduates from Nigerian universities and polytechnics has been a major source of concern to most industries in Nigeria. Most industries’ complaints stem from inadequate skill requirement for most cutting edge technologies, low practical knowledge and lack of confidence. Hence, most Nigerian engineering graduates are subjected to several retraining programmes since most of them are considered non-employable going by the quality of training they acquired from their various institutions. Following the trend in rising population, economic recession and social dynamics, it becomes pertinent that engineers owe a duty to do designs and implement sustainable systems and technologies with multidisciplinary implications. The engineers/technologists will need to poses such skills as technical know-how, critical thinking, creativity, life-long learning and team work among others, which underpin performance effectiveness in a wide array of settings or contexts. These skills (born out of teachings) are an integral part of what is expected from universities/polytechnics and therefore it beholds on every engineering faculty/school to ensure that appropriate curriculum, instructional strategies and assessment are designed to meet these demands.

Keywords: Creativity, Critical thinking, Engineering, Team work, Technical know-how

APPLICATION OF STRUCTURAL EQUATION MODELLING IN CONSTRUCTION INDUSTRY RESEARCH: CONCEPT AND PROSPECTS

¹ Abdullahi Yusuf Waziri,²Mustapha Yakubu and ³Muhammad Sa’adiya Ilyasu

¹Department of Quantity Surveying, Faculty of Environmental Technology, ATBU, Bauchi.

²Department of Quantity Surveying, Faculty of Environmental Technology, ATBU, Bauchi

³Department of Architecture, Faculty of Environmental Technology, ATBU, Bauchi

E-mail: aywaziri@gmail.com,citihills@gmail.com, sandyilyas@gmail.com

ABSTRACTS: Research in social sciences deals with constructs that cannot be directly measured. In light of this, the authors offer a consumer’s guide to the concept, application and prospects of using structural equation modelling in construction industry research as a potential methodology for the modelling of relationships among constructs. Consequently, the study dwells on the underlying concept surrounding the use of SEM with in-depth discussions on the general uses of SEM, steps involved in SEM (model specification, identification, estimation, evaluation and modification) and two-stage SEM approach. The study concludes with presentation of various examples where SEM was used in construction industry research to argument the already discussed concept and principles of SEM.