http://ir.bdu.edu.et/handle/123456789/10163 2001-01-13T05:52:04Z 2001-01-13T05:52:04Z Zebider, Getnet http://ir.bdu.edu.et/handle/123456789/16585 2025-03-10T06:42:03Z 2024-09-01T00:00:00Z

Major Factors Affecting the Academic Performance of Students in Technical Drawing Subject, Some Selected General Secondary Schools in Bahir Dar City Administration Zebider, Getnet The study was designed to assess Key Factors Affecting the Academic Performance of Students in Technical Drawing Subject in Some Selected General Secondary Schools in Bahir Dar city Administration. The general objective of this study was to identify the factors that affect academic performance of students in technical drawing subject. some selected General secondary Schools in Bahir Dar city Administration. The study used an explanatory sequential research design. Participants of the study were 305. The data sources of this study are primary and secondary data sources. The primary data is collected through structured questionnaires, Interview and Focus group discussion and secondary data collected through document analysis of annual performance reports and rosters. To analyze the extent and trends of academic performance of students the study used descriptive statistics and to assess the factors that affect academic performance of students ordinal logistic regression was used. The trend of students’ academic achievement showed a decreasing pattern of academic performance over time in a fluctuating manner. The ordinary binary logistic regression model result revealed that the students’ parent educational status, class safety, the number of days spent for practice of technical drawing in a week, personal issue related factor ,personal factors related to drawing ,technical drawing subject teachers Related Factors, computer Aided Instruction related factors school related factor and cooperative teaching method related factors were significant determinant of students’ academic performance while the sex of respondents, traditional method of teaching related factors and parental related factors were insignificant determinants. Eventually the major challenges that affect the teaching and learning process are lack of technical drawing practicing room, scarcity of technical drawing graduate teachers and lack of technical drawing subject instruments. To conclude, the significant factors that affect students’ performance together with its challenges worsen the academic performance of students. This study recommended that stakeholders that their duties related with students’ academic performance should focus their attention on the significant factors that affect students’ academic performance by developing and implementing different coping mechanisms. Key words: Cooperative Learning, computer Aided Instruction, Academic Performance, Drawing, Instrument 1

2024-09-01T00:00:00Z TESHALE, TUFA JIMA http://ir.bdu.edu.et/handle/123456789/16584 2025-03-10T06:39:45Z 2024-09-01T00:00:00Z

ASSESSMENT OF STUDENTS’ ATTITUDE TOWARDS TECHNICAL DRAWING IN SOME SELECTED SECONDARY SCHOOLS OF DIRE DAWA ADMINISTRATION TESHALE, TUFA JIMA This study examines students’ attitudes towards technical drawing in selected secondary schools within the Dire Dawa Administration of Ethiopia. The primary objectives were to assess students’ attitudes, identify key factors influencing these attitudes, and evaluate any significant differences between male and female attitudes. Employing a descriptive survey research design, the research utilized qualitative interviews with six teachers from three selected secondary schools and quantitative data from a sample of 305 students, comprising 52.1% males (159) and 47.9% females (146). The findings indicate that students generally hold a negative attitude towards technical drawing. Key factors contributing to this perception include limited job opportunities associated with the field, insufficient teaching and learning materials, inadequate classroom conditions, lack of encouragement, and the exclusion of technical drawing from national university entrance examinations. Minimal gender differences were found, with both male and female students displaying similar levels of interest and engagement. Additionally, the impact of extracurricular activities related to technical drawing was limited. In light of these findings, the study recommends targeted interventions to enhance student engagement and perceptions of technical drawing. These include improving job opportunities in the field, addressing material shortages, enhancing classroom conditions, increasing student encouragement, and integrating technical drawing into national university entrance requirements. Keywords: Attitude, Technical Drawing, Key Factors,

2024-09-01T00:00:00Z Shekur, Yesuf http://ir.bdu.edu.et/handle/123456789/16583 2025-03-10T06:37:23Z 2024-10-01T00:00:00Z

Bio-Inspired Optimization and Experimental Evaluation of Composite T-Joint to Improve Quasi-Static Mechanical Properties Shekur, Yesuf Composite T-joints consist of the skin, stiffener and flanges made of carbon fiber/epoxy laminate, which are joint by adhesive bonding. A long-standing problem with T-joints is cracking between the skins and flange due to the low strength and the presence of a large geometric stress concentration. The composite T joint structure has become a potential lightweight another option in aviation, aerospace, construction and vehicle engineering. The aim of this research is to apply bio-inspired optimization and experimental evaluation of composite t-joint to improve quasi-static mechanical properties. This study focused on tree branch-trunk joints and carbon fiber reinforced polymer (CFRP) T-joints using finite element analysis (FEA) and bio-inspired optimization techniques for the design and analysis to enhance structural performance. The study starts with a static structural analysis of tree branch-trunk joints using ANSYS 2022 Workbench to determine the maximum and minimum equivalent stress under applied loading conditions. The optimization of process parameters achieved through a combination of Artificial Neural Networks (ANN) and Multi-Objective Genetic Algorithms (MOGA). Basic findings indicate that FEA identified maximum bending stress of 109.60 MPa, tensile stress of 96.831 MPa and compressive stress of 54.769 MPa achieved at specific geometrical configurations. The ANN model demonstrated a high predictive capability with a mean absolute error of 0.311% confirming its suitability for this study. For the CFRP T-joint analysis optimization of the stiffener ply stacking sequence significantly improved mechanical properties. The bio-inspired design utilizing a stacking sequence of [45/0/-45/90/45/-45/0/90] achieved a 33.62% reduction in tensile stress and enhanced strength under various loading conditions. Experimental results indicated that the bio-inspired design improved bending strength by 15.7%, tensile strength by 16.2% and compressive strength by 16.49 % compared to the baseline design with the foam-embedded design exhibiting even greater strength improvements. The FEA results indicated in the bending load case it achieved decreases of 4.18% in normal stress, 56.31% in equivalent stress and 56.61% in maximum failure. The tensile load analysis revealed a 22.70% decrease in maximum failure for the Foam-Embedded design. Under compressive loads it achieved with decreases of 32.39% in equivalent stress and 66.29% in maximum failure. The Bio-inspired design also showed improvements particularly a 30.71% decrease in maximum failure. Overall the findings confirm that bio-inspired and foam-embedded design are effective in improving the strength and damage resistance of composite T-joints across bending, tensile and compressive loading conditions. Keywords: Nature-inspired optimization; Finite Element Analysis; Composite T-joint; Carbon Fiber Reinforced Polymer; Multi-Objective Genetic Algorithms; Artificial Neural Networks

2024-10-01T00:00:00Z Nigatu, Abebe http://ir.bdu.edu.et/handle/123456789/16582 2025-03-10T06:33:56Z 2024-09-01T00:00:00Z

Design and analysis of manually and electrically operated dough mixer machine for small scale application Nigatu, Abebe The traditional practice of manually kneading dough in developing countries is labor-intensive and time-consuming. This research proposes a hybrid dough mixer machine designed to enhance efficiency and affordability in dough preparation for traditional products like injera and bread. By integrating both manual and electric operations, the machine aims to improve accessibility for small and medium-sized house hold, restaurant and hotel in lower-income communities. The hybrid design features a 3hp electric motor combined with a pulley and belt system for automated mixing, and a hand crank for manual operation. The machine has a batch mixing capacity of 22kg, with an overall working capacity of 88kg per hour. Comprehensive design analyses were performed on critical components including the aluminum cylinder, pulleys, hand crank lever, stainless steel helix blade, shaft, bearings, and main frame. Key results indicate that the aluminum cylinder is optimally sized for effective dough mixing. The hand crank lever and helix blade, made from mild steel and stainless steel respectively, are engineered to withstand significant mechanical stresses. The stainless steel shaft is robust against bending, shear, and tensile forces, while the selected bearings are expected to last approximately 2.46 years under normal conditions. The mild steel main frame provides strong structural support with ample safety margins. This hybrid dough mixer machine offers a practical solution by combining functionality and cost-efficiency, presenting a viable alternative to imported models. It addresses the diverse needs of users by providing both manual and electric options, thus improving dough preparation in resource-limited environments. Key words: - dough, hybrid, kneading, cylinder, blade, hand crank, shaft

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