ESTIMATION OF GLOBAL SOLAR RADIATION USING SUNSHINE AND TEMPERATURE BASED MODELS IN MAKURDI, NORTH-CENTRAL, NIGERIA

Benjamin Ternenge Abur¹, Francis Fanen Abur², Emmanuel Enemona Oguche³ and Godwin E. Ede⁴

¹Department of Mechanical/Production Engineering, ATBU, Bauchi

²Projects Development Institute Enugu, Nigeria

³Industrial Skills Training Centre, Dorayi-Kano, Nigeria

⁴Department of Mechanical Engineering, University of Jos, Nigeria

Email: engrbenjaminabur@gmail.com;

ABSTRACT

Precise knowledge of solar radiation distribution at a particular geographical location is of great significance for the development of solar thermal and photovoltaic energy devices. The monthly mean daily data for global solar radiation and sunshine hours for a period of ten years for Makurdi (Latitude 7.7322°N, 8.5391°E) were obtained from the Nigerian Meteorological Agency, and used to develop a number of first order Angstrom-type correlations. The regression constants of ‘a’ and ‘b’ in Angstrom-page equation were found to be 0.273 and 0.558 respectively. Maximum and minimum measured monthly mean global solar radiations were 20.09 and 13.25MJ/m²/day which occurs in the months of November and August respectively. Estimated monthly clearness index and monthly sunshine duration were used in modeling four temperature-based and two sunshine-based models. Estimated values of global solar radiation by the various models and the measured solar radiation were tested using statistical tools of mean bias error (MBE), root mean square error (RMSE), mean percentage error (MPE), relative root mean square error (RRMSE), coefficient of residual mass (CRM), and Nash–Sutcliffe Coefficient (NS).  The values of coefficient of determination (R²) were also determined for each developed equation. Comparing these models, it was observed that the Louche model equation performed better in terms of coefficient of determination (R²) and least values of MBE, RMSE, MPE, and CRM while, Hargreaves-Samani model have the least R².

Keywords: Solar Radiation, clearness index, sunshine hours, regression constants and statistical tools

CHARACTERIZATION AND PRODUCTION OF AJASE – IPO CLAY IN KWARA STATE AS REFRACTORY MATERIALS FOR FURNACE LINING

M. Alagbe and F. F. Ihogbetin

Department of Metallurgical Engineering

Kwara State Polytechnic, Ilorin, Nigeria

E-mail: alagbemic@yahoo.com, amenosahon@yahoo.com

ABSTRACT

Characterization and physical production of Ajase – Ipo clay in Kwara State as refractory material was carried out with a view to determine its possible applications. Twenty-four different clay mixes were prepared to test for each property. The clay mixes were formed with clay, 5%ww sodium silicate and 5%ww tempering water addition. Prepared samples were heated to temperature of 800, 900, 1000, 1100, 1200 and 1300⁰C, soaked for 2 hours and allowed to cool to room temperature. Testing of properties such as gas permeability, apparent porosity, linear fired shrinkage, hot strength, baked strength, baked hardness and refractoriness were carried out on standard samples of these mixes. The experiment was carried out for both the local clay (Ajase-Ipo) and imported refractory materials (London and India). The result of the tests showed Ajase-Ipo clay mix has average values of 151ml/min gas permeability, 520KN/m² hot strength, 685KN/m² baked strength, 94.7BH baked hardness, 14.47% apparent porosity and 24% linear shrinkage at 1300^OC. These properties compared with clay materials used in local foundries for ferrous castings and could be a suitable replacement for those clay mixes in use at present.

Keywords: Characterization, production, clay, bond, furnace

IMPACT OF PEER ASSESSMENT ON STUDENTS’ PRACTICAL SKILLS ACQUISITION IN ELECTRONICS WORKS TRADE IN GOVERNMENT SCIENCE AND TECHNICAL COLLEGES OF ADAMAWA STATE NIGERIA’

P. C. Duhu & Ishaku Zechariah

Department of Electrical Technology Education

Modibbo Adama University of Technology, Yola, Adamawa State

Email:  patrickchindad@gmail.com

ABSTRACT

The study assessed the Perceived Impact of Peer Assessment on Students’ Practical Skills Acquisition in Electronics Works Trade in Government Science and Technical Colleges of Adamawa State Nigeria’. To carry out the study, two research questions and two hypotheses were formulated. Descriptive survey research design was adopted for the study. Eighty-nine respondents comprising of eighty-three students and six electronics works trade teachers of Government science and Technical Colleges (GSTCs) of Adamawa state formed the population of the study. No sampling was used because the population was manageable. The instrument for data collection was a 57-item structured questionnaire named: ‘Impact of Peer Assessment on Students’ Practical Skills Acquisition Questionnaire (IPSPSAQ) developed by the researcher’. The instrument was validated by three specialists from the Department of Electrical Technology Education. Cronbach Alpha formular was used to compute a reliability index of 0.89 for the instrument. The instrument for data collection was administered to the respondents with the help of two research assistants; data obtained were analyzed using Statistical Package for Social Sciences. Mean and Standard Deviation were used to answer the research questions; while t-test statistic was used to test the hypotheses at 0.05 level of significance. The findings of the study indicated that gender does not have influence on students’ performance in electronics work trade in technical colleges in Adamawa state”. The findings also revealed that, Peer Assessment enhances students’ academic performance in Electronics Works Trade. Both the null hypotheses were upheld. The researcher recommended based on the findings that Electronics Works Trade teachers should adopt the use of Peer Assessment in assessing students since it has been found effective in improving students’ skills acquisition in Electronics Works Trade.  Government should organize workshops, conferences and seminars to train teachers on the use of Peer Assessment

Keywords: Peer Assessment, Students’ Motivation, Practical Skills Acquisition, Electronics Works Trade.