Relevance of Computer Assisted Instruction (CAI) for Effective Skill Development among Technology Education Students in Nigeria

The main purpose of the study reported is to show how computer assisted instruction (CAI) has significantly impacted on all aspects of our live particularly on education, it has radically influenced the way knowledge and information are generated, developed and transmitted in technology education. Every technology teacher must be acquainted with how to apply CAI in teaching technology education programme since teachers have a vital role in trainees skill development. Therefore, this study was designed to determine relevance of computer assisted instruction for effective skill development among technology education students in Nigeria. A descriptive survey research design was adopted. The study was guided by two research questions and two hypotheses, tested at 0.05% level of significance. The respondents for the study comprised of 310 technology vocational teachers.  Mean and standard deviation were used to analyse the research questions, while t-test statistics was employed to test the hypotheses. The findings of the study among others revealed that technology vocational teachers should be skilful in using CAI in the production  of  teaching materials that can be used in developing appropriate skills, incorporate the  use of media and technology for teaching where appropriate and technology vocational teachers teaching and managing courses through web-based system. It was recommended that Federal government should ensure that her policy statement regarding the provision of necessary infrastructure and training for use of computer in the school system is effectively implemented and making it mandatory for technology vocational teachers  in developing computer skills needed in classroom environment. This could be achieved through adequate financial provision for tools and resources. Key words: Computer assisted instruction, Technology education, Technical vocational teachers, and Skill development

A broadband cooperative relay-based system for power line communication

Demand for data for various broadband applications has placed the power line communication (PLC) in a prime place. In PLC, the existing electrical power installation in the last mile is used as the transmission medium, hence no new installation is required. Since transmission of broadband data was not intended over the electrical power installation, the network (power line) poses a great deal of impediment to broadband data as it traverses the medium. These impediments are, attenuation over the length of the cable, noise (impulsive and Gaussian), and multipath fading. Hence, signals propagation over the line is either received corrupted at the destination or lost out rightly. This work implements a technique to maximize channel capacity, reduce attenuation characteristic, symbol error rate and outage probability in the PLC. Performance of the system is compared with those of MIMO-PLC and PLC-repeaters (PLC-rep.). In the first instance, the attenuation over the long length of the power line network was combatted. A customized cooperative relaying system, implementing amplify-and-forward (AF) and decode-and-forward (DF), with placement of the relay modem at three different locations along the network in the PLC was developed. A noise mitigation system was incorporated to improve the system’s bit error rate (BER). The systems’ performance for channel capacity improvement between 18.32% and 73.5% and 144% and 260% over the MIMO-PLC and PLC-rep. was achieved for AF and DF schemes respectively. SER reduction on the PLCC AF and DF are 43.41% and 85.16% over the MIMO-PLC and 69.26% and 91.9% over the PLC-rep., while outage probability reduced by 96.2% and 99%. Attenuation reduction to 31.4% was achieved with the DF link when the relay was placed 10 m away from source node. To achieve performance maximization inspite the branches on the network, PLCC multiple relaying scheme, having three different multiple relay scenarios was arrayed. Selective relaying, implementing best relay channel instantaneous SNR, was deployed for AF and DF, hence, best relay is selected. Selective relaying improved the system’s channel capacity by 201%, 303% and 70.6% over MIMO-PLC, PLC-rep. and PLCC (fixed) respectively. Owing to the noise mitigation system, the SER reduced 400% over the duo of MIMO-PLC and PLC-rep. and by 79.37% over the PLCC (fixed) schemes. Outage probability achieved a land marking drop over the benchmark links and 87.5% over the PLCC (fixed) link. Further reduction in attenuation was achieved to 64.1% with the 7 relay DF deployment. Finally, to keep the system’s maximized performance within the electromagnetic compatibility framework, optimal power ratio was developed for optimal power allocation between source and relay modems. Objective function for maximizing and minimizing the direct and cooperative transmission power was developed for optimal power ratio. The optimal power allocation (OPA) algorithm allocates one-third and two-third of the transmitted power (Pt) to the source and relay modems, direct and cooperative transmissions respectively. Channel capacity improved by 274% and 44.37% over the MIMO-PLC and equal power allocation (EPA) scheme and achieved 457% improvement over the PLC-rep. SER with OPA reduced drastically over the benchmark links and 76.1% over the EPA scheme, while outage probability further reduces with OPA largely over the benchmark links and 90% over the EPA. The attenuation reduction is also prominent with the OPA scheme. The abstract is a digest of the entire thesis and should be given the same consideration as the main text. It does not normally include any reference to the literature. Abbreviations or acronyms must be preceded by the full term at the first use