Open Access Original Research Article

Open Access Original Research Article

Credit Risk Analysis of Ethiopian Banks: A Fixed Effect Panel Data Model

Tsegaye Tibebu Jabir, Nigatu Degu Terye

Current Journal of Applied Science and Technology, Page 1-16
DOI: 10.9734/BJAST/2016/23563

The role of banks is very vital in the overall development of a given country. While Credit risk is one of the main risks of banks and affects the development of the financial system, little study is done to examine its determinants. This study was conducted to investigate the factors that affect credit risk of Ethiopian commercial banks. It covers a time period from 2003 to 2009. Both macroeconomic and bank specific credit risk factors were investigated using fixed effect panel data model. The credit risk of the sampled bank was 7.08% for the test period. It was higher than its international limit which is 2%. The study showed that leverage, operating inefficiency, loan growth, ownership and loan to deposit ratio are significant determinants of credit risk of Ethiopian commercial banks in the test period. The empirical finding of the study also showed an existence of a clear difference on credit risk level between government and private owned commercial banks. Particularly government owned banks should devise ways to lower their credit risk since they are found to be more risky than private ones. Generally, in this study bank specific variables have more significant effect than macroeconomic variables. So, bank managers and policy makers should deal with bank specific factors effectively.

Open Access Original Research Article

Co-authorship Networks in Additive Manufacturing Studies Based on Social Network Analysis

Denghui Zhang, Yang Guo, Zhengxu Zhao, Yiqi Zhou

Current Journal of Applied Science and Technology, Page 1-6
DOI: 10.9734/BJAST/2016/24462

In the last 30 years there has been growing interest in additive manufacturing technology. Co-authorship of published papers plays such an important role in scientific development. The collaborative research social network on the field of additive manufacturing is paid particular attention in this paper. A framework based on open source software is proposed to automate the data collection and social network analysis. The characteristics of the overall network structure is analyzed and visualized. The development process of AM collaboration community mode is discussed. So as to provide inspiration for collaborative research and further development of additive manufacturing technology.

Open Access Original Research Article

The Field Performance of Palm Fibre Insulation Board Treated with Cassava Starch

M. Ekoja, A. O. Edeoja, O. M. Injor

Current Journal of Applied Science and Technology, Page 1-8
DOI: 10.9734/BJAST/2016/23998

The field performance of palm fibre insulation board treated with cassava starch solution has been studied. This was done in search of local substitutes for imported insulation materials used in low temperature (45°C – 200°C) ovens. Fresh oil palm fibre was collected from palm-kernel, washed with non-reactive detergent to remove its oil content and dried to constant mass in an oven. The dried palm fibre was treated with 0.2 w/w starch solution, compacted into rectangular boards and re-dried in an oven to constant mass. The fibre bands were then installed in a locally developed oven for the field test. The test involved examining the stability of the thermo-physical properties of the insulation board after baking activities for 4 hours. This was done by comparing the density, physical appearance and thermal conductivity of the board before and after the use in the oven for baking. There were no significant changes in the thermo-physical properties observed before and after use. The results indicate that the palm fibre board is suitable for use as an insulation material in low temperature oven application. Successful implementation of the board could contribute greatly to savings on importation costs of conventional insulation materials while enhancing the safer utilization of a by-product of the Nigerian palm oil industry. Furthermore, this will enhance better environmental conditions and comply with the current clamor of converting waste to riches.

Open Access Original Research Article

Comparative Analysis of Back Propagation Neural Network and Self Organizing Feature Map in Estimating Age Groups Using Facial Features

E. O. Omidiora, M. O. Oladele, T. M. Adepoju, A. A. Sobowale, O. A. Olatoke

Current Journal of Applied Science and Technology, Page 1-7
DOI: 10.9734/BJAST/2016/24303

Aim: This paper presents a statistical analysis of the performance of two age estimation algorithms namely Back Propagation Neural Network (BPNN) and Self Organizing Feature Map (SOFM) on human face images.

Methodology: 630 human face images with age ranges 0 - 69 from the FG-NET database were considered, feature extraction was done using Principal Component Analysis (PCA) and classification was done using BPNN and SOFM. Two way ANOVA was used to analyse if there is significant difference between the two algorithms (BPNN and SOFM) by feeding in all the parameters such as training time, number of correctly classified, number of near-correctly classified, number of incorrectly classified and percentage accuracy.

Results: The results of the analysis shows that there is significant difference between BPNN and SOFM in the age estimation using facial features.

Conclusion: The results from the statistical analysis (Analysis of Variance (ANOVA)) reveals that SOFM is better than BPNN because F-critical > F for the column and the decision rule states that we accept H0 i.e. there is significant difference between BPNN and SOFM if F-critical > F when the results (training time, testing time, number of correctly classified, number of incorrectly classified and accuracy) were compared and tested.

Open Access Original Research Article

Instrumental Approach to the Determination of Ozone Phytotoxicity

Andebo Waza, Alemayehu P. Washe

Current Journal of Applied Science and Technology, Page 1-8
DOI: 10.9734/BJAST/2016/24821

Ozone (O3) phytotoxicity is a serious concern all over the globe. O3 can cause both biochemical and physiological changes to plants that could lead to reduction in growth and yield. Its effect on agricultural crops is usually detected as foliar injury. Although foliar injury has frequently served as physiological basis for monitoring performance of agricultural crops and assessing air quality, its visibility depends on period of exposure, concentration of ozone, and environmental conditions. The present study focused on the determination of biochemical indicators of ozone phytotoxicity including Rubisco (biochemical indicator for carbon assimilation), photo-pigments [carotenoids and chlorophyll (a & b)], and chlorophyll photochemical efficiency on a judiciously selected plant-Nicotiana tabacum (Tobacco), variety: Little Havanna. An enclosed computer controlled growth chamber was used for cultivation of the experimental plant groups (ozone exposed and control). Spectrophotometric measurements of the biochemical indicators were carried out to evaluate the exposure-response behaviour of the plant. Our results showed a significant (P< 0.05) decrease of the biochemical indicators that is reproducible even when foliar injury is not detected. Besides, experiments also showed that chlorophyll a is more sensitive to ozone than chlorophyll b. The instrumental readings were supported by a reduction in total organic nitrogen and starch content and ultimate decrease in growth rate and root: shoot ratio. While significant variations in the intensities of foliar injury can be detected among plants within a group, a reproducible exposure-response data were obtained from instrumental measurements. Such measurements can also serve as basis for the development of implantable sensors for in-situ monitoring of ozone pollution in sensitive crops.

Open Access Original Research Article

Potentials of Using Moringa oleifera Seeds in the Bioremediation of Soil Contaminated by Crude Oil

T. D. T. Agboun, T. U. Apugo-Nwosu, J. A. Mohammed, A. O. Ameh, G. Abubakar, M. Mustapha, P. Okoro

Current Journal of Applied Science and Technology, Page 1-8
DOI: 10.9734/BJAST/2016/9358

The potential of using Moringa oleifera seed cake to increase the rate of the microbial degradation of crude oil-spilled soil was investigated. This investigation was carried out at the National Research Institute for Chemical Technology, Zaria, Nigeria, within a 28 day period in the month of May, 2012. The proximate analysis of Moringa oleifera seed cake was found to contain nitrogen (10.55%), phosphorus (18.33 ppm) and organic carbon (1.06%). Likewise hydrocarbon degrading bacteria were isolated using spread plate method. The results revealed that the counts of crude oil degrading bacteria in crude oil polluted soil amended with Moringa oleifera (sample C) increased to 3.6 x 106 CFU/g, with a growth rate constant of 0.06 as compared with that of unamended polluted soil (sample B), whose counts increased to1.5 x 106 CFU/g, with a growth rate constant of 0.019. Moringa oleifera seed cake was found to enhance the degradation in crude oil polluted soil compared to unamended crude oil polluted soil by 64.3%. pH of crude oil polluted soil sample amended with Moringa oleifera seed cake ranged between 7.24 and 7.70 while that of unamended crude oil polluted soil ranged between 7.24 and 7.44. This implies that Moringa oleifera has a buffering effect which enables micro-organisms to proliferate. Statistical analysis showed no significant difference (p>0.05) between rate of biodegradation of crude oil in soil amended with Moringa oleifera seed cake as against that of unamended crude oil polluted soil. The results of this study show that Moringa oleifera seed cake is suitable for bioremediation of crude oil polluted soils.

Open Access Original Research Article

Outdoor Air Quality and Acid Rains within Warri Refinery and Its Environs

U. E. Amuho, I. A. Amoo, O. O. Ajayi, A. F. Aiyesanmi, T. A. Akinnifesi

Current Journal of Applied Science and Technology, Page 1-6
DOI: 10.9734/BJAST/2016/23688

The focus of the research was to assess the impact of the Warri Refinery operations on the outdoor air quality within the refinery and its environs. The Warri Refining and Petrochemical Company (WRPC) is an industrial complex of the Nigeria National Petroleum Corporation (NNPC) downstream sector, located between Ekpan and Ubeji communities of Delta state of Nigeria. Outdoor air quality within the refinery, Ubeji and Ekpan communities were checked for the concentration of hydrogen sulphide, carbon dioxide, toluene, benzene and perchloroethylene. The results from the study revealed the presence of benzene, toluene and hydrogen sulphide within the outdoor air of the refinery and its environs in almost constant concentrations. However, these gases/vapours are present in concentrations lower than the Federal Environmental Protection Agency (FEPA) listed limits. Also, rain water samples from within the refinery, Ubeji and Ekpan communities were collected for three consecutive years during the raining season and the water samples checked for acidity. There were complaints by some residents of the environs about frequent eye irritation which they link to the rather heavy gaseous emissions. The results from the study also further underscores the need for continuous monitoring of outdoor air quality especially in settlements and rural communities bordering areas with high industrial activities.

Open Access Original Research Article

Purification and Characterization of Carbon Nanotubes and Prospects for the Formation of Magnetic Semiconductor via Iron Incorporation

Chernet Amente, Keya Dharamvir

Current Journal of Applied Science and Technology, Page 1-9
DOI: 10.9734/BJAST/2016/18853

This article reports the synthesis of iron (Fe) encapsulated carbon nanotubes (CNTs) prospective to the formation of magnetic semiconductors, by the arc discharge method. Morphology of the samples was studied from transmission electron microscope (TEM) and scanning electron micrograph (SEM) imaging. The data was recorded by x-ray diffractometer (XRD) and energy dispersion x-ray (EDX) equipments for the identification of the sample constituent. TEM images of metal added samples indicate that defects are completely removed after mono acidic treatment and open air oxidizing at 400°C for 15 minutes leaving nano sized carbonaceous skeins attached on the surface of carbon nanotubes and catalyst particles encapsulated. This formation is recognized as a phenomenon at certain temperature limit. From the SEM analysis, a new phenomenon of spherical structure with diameter nearly 15 µm to which bundles of CNTs and carbonaceous impurities are attached is observed. EDX examination shows that the carbon weight % is dominating the composition along with oxygen and iron, perhaps, forming FeO during the reaction. It is also revealed from XRD analysis, indicating success in metal incorporation. This envisages that there would be formation of magnetic semiconductors, as it can be verified with further experiments, where iron ions may take carbon cites in the CNTs with semiconducting behavior and iron filling otherwise.

Open Access Original Research Article

Analysis of Corrosion Behaviour of Welded Austenitic Stainless Steel Immersed in Aqueous Alkaline Medium

I. M. B. Omiogbemi, D. S. Yawas, I. M. Dagwa, F. G. Okibe

Current Journal of Applied Science and Technology, Page 1-8
DOI: 10.9734/BJAST/2016/23837

Aims: This research is aimed at investigating the corrosion behaviour of welded austenitic stainless steel (ASS) immersed in an alkaline sodium hydroxide medium. The tensile properties of the structure were also determined.

Study Design: Weight loss method, Factorial Design of Experiment and scanning electron microscope were used for the analysis.

Place and Duration of Study: Department of Mechanical Engineering, Ahmadu Bello University, Zaria, Nigeria, between March and November, 2014.

Methodology: The corrosion behaviour of type 304 austenitic stainless steel (ASS) immersed in sodium hydroxide (NaOH) medium (0.5 M) at ambient temperatures was investigated using conventional weight loss method together with factorial design of experiment, scanning electron microscopy (SEM), Gas metal arc welding machine. The design expert was used to determine the surface responses and interactions between the parameters; SEM was used to examine the test specimen microstructural analysis after immersion in the basic medium while the Monsanto Tensometer was used to examine material optimum performance in hydrochloric acid medium in terms of strength.

Results: It was found that tensile strength increased with increasing welding parameters (from 189 MN/m2 to 203 MN/m2). It was also found that increase in welding current and speed at constant voltage gave the optimum performance of the ASS structure in NaOH medium obtained at speed 40 mm/sec and current 110 Amp. Surface corrosion deposit composition was analyzed with the SEM paired with energy dispersive spectrometer (EDS).

Conclusion: This research shows that corrosion susceptibility of ASS in sodium hydroxide medium during the exposure time period studied is due to the aggressiveness of the hydroxyl ion (–OH). The materials’ susceptibility to stress corrosion cracking was conspicuous after a successful corrosion analysis in the medium with a tensile test results. It was concluded that relatively high speed and current at a constant voltage gave a satisfactory weldment of the structure.