AMU Journal System (Arba Minch University)
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The Hydraulic Performance Analysis of Existing and Revised Water Supply Distribution Network, a case of Dukem Town in Ethiopia
No full textAnalysing the status of a town’s water distribution network is necessary to monitor its current and future management patterns. Dukem Town's existing water distribution system is not properly functioning, and the utility does not deliver the required demand to customers due to fluctuations in pressure and demand. Thus, the main goal was to analyse the town's water distribution system’s hydraulic performance and the users’ perceptions. Level of consumer’s satisfaction with the town's water delivery services was examined among 376 households. The WaterGEMS model was calibrated using eight node data points at minimum and peak hour consumption, with corresponding R2 of 0.97 and 0.99, respectively. The result of the analysis at steady state simulation indicated that only half of nodes have pressure within the desired limit of 10–70 m of water; the remaining 45.11% and 4.51% of the nodes have pressure above and below the desired limit of pressure, respectively, at average daily demand. At peak hour demand, the nodes with pressure within the desired limit reduced to 34.3%. The analysis of pipe velocity showed that only 45.71 and 48.57% of pipes have a desired limit of velocity (0.5-2 m/s) at average daily demand and peak hour demand, respectively. The extended-period simulation showed 45.36% of the nodes to have pressure within the desired limit, whereas 51.88 and 3.76% of nodes had pressure above and below the desired limit, respectively. However, 62.86% of pipes had less than the allowable velocity limit for the extended period. By applying pressure-reduced valves, it was possible to keep 99% of the nodes' pressures within the desired range. Even though there are water interruptions, the customers’ satisfaction with the existing water supply service is 55.4%. To provide reliable water supply service, utility officials need to work on modified network by involve community for its sustainable management.
Keywords: Customers Perceptions, Dukem Town, Hydraulic performance, WaterGEMS, Distribution Network
Prevalence and potential risk factors of bovine clinical mastitis in Bonke District, Gamo Zone, Southern Ethiopia
Get PDFEthiopia has the largest cattle population in Africa with an estimated population of 56.71 million. Among these, the cow represents the biggest portion of the cattle population of the country. Currently, around 20.7% of the total cattle heads are milking cows. 85-89 percent of milk is contributed from cattle out of the total annual national milk production in Ethiopia that ranges from 797, 9000 to 1, 197, 500 metric tons of raw milk equivalents.. However, this amount does not satisfy the national demand for milk and milk products in the country due to a number of complex and interrelated factors including inadequate feed and nutrition, widespread diseases, the poor genetic potential of local breeds, poor market chain, and inefficiency of livestock development. Concurrently, mastitis is one of the major and expensive diseases which can alter milk composition, reduce the quality and quantity of milk yield, and indeed cause the culling of dairy cows at their age of high productivity. Clinical mastitis is the types of mastitis emphasized in this study. A cross-sectional study was conducted on 384 lactating cows to assess the prevalence of bovine clinical mastitis and its potential risk factors in the study area. Out of these 41(10.7%) were found positive for clinical mastitis. All the potential risk factors considered in this study showed statistically significant difference (P < 0.05). The present study concludes that mastitis was a key health problem of lactating cows in the area. Therefore, deliberate control measures against the disease and regular reconnaissance measures are recommended.
Keywords: Bonke; Bovine clinical mastitis; Prevalence; Risk facto
Analysis of lowland smallholders’ vulnerability to climate change in the rift valley areas of Arba Minch Zuria district, southern Ethiopia
No full textThe study assessed smallholders’ vulnerability to climate change and variability, which challenges development in rural-lowland kebeles of Arba Minch Zuriya District, Southern Ethiopia. 360-questionnaire survey households were the main sources from which primary data was gathered. Both purposive (non-probability) and systematic random probability sampling techniques were used to select the respondents. Secondary data were obtained from relevant published and unpublished materials. The livelihood vulnerability index (LVI), the LVI-IPCC on Climate Variability, and descriptive statistics were used to analyse the extent of smallholders’ vulnerability to climate variability. The results revealed a significant increment in the average annual temperature, no clear pattern in annual rainfall, and higher rainfall variability. Adaptive capacity (0.5139), sensitivity (0.683), and exposure (0.5043) were the three contributing factors weighted while quantifying the smallholders’ vulnerability extent. Technically, 3 dimensions of livelihood vulnerability categorized into 5 major components with their index values for demographic profile (0.5375), livelihood strategies (0.448), infrastructure and social networks (0.5564), health (0.3252), and food and water (0.4242) were used to calculate smallholders’ vulnerability to climate change and variability. The result of the LVI-IPCC was found to be (0.056). Resilience-building and adaptation methods are critical for minimizing the vulnerability of smallholder farmers. It is suggested that agriculture specialists and other concerned stakeholders should work together to develop lowland-appropriate rural livelihood vulnerability reduction measures.
Keywords: Adaptive capacity; Arba Minch Zuriya; Climate change; LVI; Smallholders  
Design and Construction of a High-Efficiency Biomass Charcoal Kiln in Ethiopia
Get PDFThis study aimed at the design and construction of a high-efficiency biomass charcoal kiln in Ethiopia. Traditionally, local communities in Ethiopia use a premival and inefficient technique of charcoal making to which very little scientific study has been directed. This conventional charcoal making process hasnumerous downsides with regard to rate of carbonization, quality, yield, pollution, labor, and land costs. The current research, therefore, aimed at the design and construction of a high-efficiency biomass charcoal kiln that reduces the above listed problems.Charcoa produced by both the traditional erth mound kiln and the newly designed and constructed improved carbonization kild were compared for their properties. The results showed the moisture content as (2, 0.89) %, the volatile matter (8.84, 3.02) %, the fixed carbon content (81.09, 91.42)%, the heating value (29.982, 32.762)MJ/kg, bulk density (342.53, 434.5)kg/m3, shatter resistance(88.8, 91.12)%, water penetration resistance (26.34, 17.99)%, ash content (8.06, 4.660)%, efficiency(16, 31)%, and production time per cycle(3, 5) days for conventional earth mound kiln and improved carbonization kiln, respectively. Based on these results, the improved carbonization kiln’s carcoal displaed higest shatter resistance of 91.12% faring well in mechanical strength, and it has high-water penetration resistance meaning it has improved water absorption and a decent heating value. The increased density means the volume is decreased due to the leakage of volatile contents and more fixed carbon content. Lastly, the modified carbonization kiln’s production was enhanced by 48.38%.
Keywords: Biomass, Carbonization, Construction, Charcoal, Design, Kiln, Molecular Weigh
Synthesis and Characterization of Mechanical and Physical Properties of False Banana (ʾənäsätə) Fiber Reinforced Composite Material
Get PDFThe use of environmentally friendly materials has recently been promoted due to increased awareness of environmental issues. To offer a better world for future generations, we must decide what we will utilize and serve today. As resources and products reach the final stage of their usability, the preservation of remaining materials and reduction of degradation emerge as challenges that must be addressed. Biodegradable materials produced from recyclable resources deal with these issues. This study intends to make a recyclable resource of false banana (ʾənəsätə) fiber as reinforcement with polyester resin composite material produced by hand lay-up method at room temperature. The mechanical and physical properties of the produced sample were investigated. include tensile, flexural, impact strength, and water absorption. The fiber surface was treated with NaOH alkaline in distilled water solution. In composites, the fiber orientations were 0o, 90o, 45o/-45o, 0o/90o, and chopped, at 40% fiber volume fraction. The sample's manufacturing process was accomplished fruitfully. A chopped sample is a simpler production process compared to the other. As the result, 0o fiber direction scored the highest tensile strength, which is 181.41MPa. In the flexural and impact strength test, a 90o oriented fiber was observed with the highest value, which is 81.43 MPa and 9.75 joules, respectively. The samples were immersed in distilled water until saturated. The highest percentage of water absorption was 45o/-45o oriented fiber. Many researchers have recently shown interest in natural fiber composites material for aerospace and automotive applications, such as aircraft radomes and interior cabin components, as well as remarks on natural fiber composites' future trends and problems. This article provides readers with a positive perspective and piques industry players' interest in the potential of using natural fiber composites in aerospace applications to improve current aerospace material performance, particularly in terms of lightweight and environmental sustainability.
Keywords: Composite, Fiber, Manufacturing, Matrix, Reinforcement, Sustainabilit
The Effect of Corporate Social Responsibility on Financial Performance of Large Manufacturing Firms in Addis Ababa, Ethiopia
Get PDFAbstract
Corporate Social Responsibility (CSR) is a concurrent issue in the world. It is the integration of social, economic and environmental aspects in business operations. The main aim of the investigation was to examine the effect of CSR practice on financial performance of large manufacturing firms in Addis Ababa, Ethiopia. In the study, to measure CSR, the dimensions such as, employee, customer, supplier, community, government and environmental-related practices of firms were used. Financial performance of large manufacturing firms was measured using ROA. Additionally, firm size was employed as a control variable to clearly understand the effect of CSR on ROA. The research was utilized explanatory research design and a quantitative research approach. The data obtained from 81 large manufacturing companies in Addis Ababa, Ethiopia. Stratified sampling method was applied to select the sample form 102 large manufacturing firms. Questionnaire and document analysis of audited financial statements served as data collection instruments. The study used multiple regression analysis model and Ordinary Least Square (OLS) parameters estimator. Based on the regression result, employee, community and government related CSR practice and firm size positively and significantly affect ROA. Suppliers’ related CSR practice has negative relationships and significant effect on ROA. Customers and environment related CSR activities have an insignificant effect on ROA. In general, large manufacturing firms are recommended to apply CSR initiatives to increase their productivity.
Key Words: CSR, Financial Performance, ROA, Large Manufacturing Firm
MODELING ACADEMIC LEADERSHIP DEVELOPMENT: LINKING COMPLETE ACADEMIC LEADERSHIP BEHAVIORS TO LEADERSHIP OUTCOMES
Get PDFThe purpose of this study was to investigate if the link between complete leadership behaviors and leadership outcomes provides new insight to advance academic leadership preparation in Ethiopia’s public universities. The cross-sectional survey research design was preferred to administer the data collection process. Using the sample size determination technique, the investigator randomly selected 450 sample units, of which the properly filled and returned were 401 (89%). Subsequently, the study employed stepwise regression analysis to investigate the best subsets of academic leadership behaviors that account to improve leadership outcomes. As result, intellectual stimulation, contingent reward, inspirational motivation, building a learning environment, idealized influence-attributions, laissez-faire, and idealized influence-behaviors were the best subsets of leadership sub-behaviors, which significantly account (R2=69.4%) to improve leadership outcomes. Thus, the complement of full-scale instructional leadership and full range leadership sub-behaviors are constituting a complete academic leadership development model, which advances academic leadership preparation in university terrain. Keywords: Modeling; Academic Leadership; Leadership Behaviors; Leadership Development; Leadership Outcom
Numerical Investigation of Reinforced Concrete Beam Containing Iron Ore Tailings as Partial Replacement of Sand
Get PDFThe production of industrial and agricultural residual byproducts can generate significant environmental impact. In response, researchers have begun incorporating supplementary materials made from agro-industrial wastes to create more sustainable concrete. However, testing the performance of these waste-based concrete mixtures can be time-consuming and expensive. To address this issue, this study utilized three-dimensional non-linear Finite Element simulation using the ABAQUS/CAE software to predict the behaviour of a reinforced concrete beam that incorporated 20% IOT as partial sand replacement. The simulation successfully predicted the damage behaviour of the 20% IOT concrete, indicating the potential of this modelling approach to accurately predict the performance of waste-based concrete mixtures in various designs.
Keywords: ABAQUS, Computer Aided Engineering, Iron Ore Tailings, Numerical Analysis, Rein-forced Concrete Bea
Landslide threat evaluation and zoning in birbir mariam district, Gamo Highlands, Ethiopia Great Rift Valley escarpment
Get PDFThe current research focuses on landslide assessment and hazard zonation in the Birbir Mariam district of the Gamo Highlands. The study examined landslide causative factors and used the slope susceptibility evaluation parameter to create a landslide hazard zonation covering an area of 110 square kilometers. The landslide hazard zonation was classified using facet-wise observation. As a result, the intrinsic and external causal parameters of score schemes have been held responsible for slope instability. Inherent causative elements consist of slope geometry, slope material (rock or soil), structural discontinuities, land use or land cover, and groundwater conditions. Rainfall and human interest have seemed like external elements. The intrinsic and external triggering elements for every facet (a total of 106) were rated for their contribution to slope instability. Finally, an evaluated landslide hazard value was calculated and classified into three landslide hazard classes. According to the findings, the area has a high hazard zone of 18.87 percent (20.76 km2), a moderate hazard zone of 54.72 percent (60.19 km2), and a low hazard zone of 26.41 percent (29.05 km2). The methodology employed in this investigation, as well as the resulting landslip susceptibility zonation map, were both reliable and applicable to other places with similar geology and topographic circumstances.
Keywords: Ethiopia; Hazard zonation; Landslide; Landslide evaluation; Slope stabilit
Pre-Service Teachers' Attitudes Toward ICT Use and ICT Integration Self-efficacy Beliefs
Get PDFIn this modern world, Information and Communication Technology (ICT) is an effective teaching tool. To effectively incorporate technology into the curriculum, teachers need to have the necessary skills, a positive attitude towards technology, and an understanding of how to integrate it into their teaching. This study, thus, aimed to investigate the pre-service teachers' attitudes towards ICT use for teaching, scrutinize their ICT integration self-efficacy beliefs, and examine the association between the teachers' attitude towards ICT use and ICT integration self-efficacy beliefs. A descriptive survey design was adopted to guide the research process and achieve the objectives of study. Data was collected through a 5 Point-Likert scale questionnaire from eighty-nine pre-service teachers at Arba Minch University. A one-sample t-test and Pearson product-moment correlation statistics were employed for data analysis. The findings of the study indicate that the pre-service teachers had a favorable attitude to ICT use and low to moderate ICT integration self-efficacy beliefs.
Keywords: Attitude to ICT use, ICT integration, pre-service teachers, self-efficacy belief