University of Dar es Salaam Library Repository
This Repository contains abstracts of theses and dissertations, and special rare collections materials available in the Library.
Recent Submissions
Adaptive anisotropic diffusion-driven model for denoising iris images
(University of Dar es Salaam, 2021-04) Kyando, Daniel M.
Biometric recognition is the automatic recognition of individuals based on their physiological or behavioral characteristics. A variety of systems require reliable personal recognition schemes to confirm or determine the identity of an person requesting access or service. IRIS recognition refers to biometric systems used to recognize individuals based on their IRIS patterns. In the absence of robust denoising method, these systems are vulnerable to the inaccurate interpretation of the patterns and granting access or service to illegitimate users.
The classical Perona-Malik model has attracted wide attention of scholars for its ability to restore corrupted images while preserving useful details (edges and contours). Despite its notable achievements, this model requires manual tuning of the shape-defining diffusion coefficient to generate optimal results. Consequently, the tuning process, which suffers from inconvenience and time-ineffectiveness limits the model in time sensitive application like interpreting the IRIS patterns. Therefore, this work presents a method to adaptively update the value of the shape-defining diffusion coefficient in relation to the noise statistics in the IRIS image.
Through a series of experiments, it was observed that the coefficient strongly correlates with the noise statistics in the IRIS image. Therefore, a relationship to describe the correlation was established and encapsulated into the evolutionary polynomial of order two. The polynomial was fitted from running 39 million iterations to generate two-dimensional space R^(K×σ) that contains K and σ variables. Least Absolute Residuals (LAR) is used to approximate the constants. The constants were α=0.00473,β=2.134,and γ=-0.3696 with 95% confidence boundary. The proposed diffusion function was further tested in removing noise in the IRIS images. It generated visually appealing denoized images with higher information content. It sharpens the edges and distinguishes them clearly from homogeneous image a region which is crucial in identification of texture patterns in IRIS images
Factors influencing entrepreneurial intentions among students: A Case of Undergraduate Students of the University of Dar es Salaam
(University of Dar es Salaam, 2023-05) Msonsa, Anna
This study examined factors influencing entrepreneurial intentions among students at the University of Dar es Salaam. The specific objectives were to examine the role of attitude, subjective norms, and perceived behavioral control in influencing entrepreneurial intentions among students. An explanatory research design and a quantitative approach was employed. The sample size was 200 university students although 182 students were reached. Data was collected through a questionnaire and analyzed by SPSS software. The study found that attitudes, subjective norms, and perceived behavioral control are important in explaining entrepreneurial intentions among students. Among other factors, subjective norms were found to have a strong influence on entrepreneurial intentions among university students accounted by 46% of the variation, followed by attitude 36% of the variation; and last one was perceived behavioral control 35% of the variation in entrepreneurial intentions among university students. In addition, the study found that subjective norms have a strong influence on entrepreneurial intentions whereby 46% of the variation in entrepreneurial intentions among university students has been accounted for by the role of subjective norms. Also, the study concluded that attitudes, subjective norms, and perceived behavioral control are strong predictors of university students‘ intention of becoming entrepreneurs. This research has proven that entrepreneurship intention has a positive relationship with undergraduate students‘ behavior in engaging in entrepreneurship. Since it was discovered that university students‘ attitudes, subjective norms, and perceived behavioral control have a significant influence on entrepreneurial intention, the study recommended that it is important that educational policies, particularly in higher learning should be well-directed in creating new attitudes among university students. This should be done in tandem with the development of instructional resources linked to entrepreneurial education. The study was purely qualitative and hence might limit in-depth information. Although the findings of the study have practical relevance, the study was conducted at the University of Dar Es Salaam which is the city context and a highly populated area. The result may alter if the study was conducted in other locations of the country.
Secondary school stakeholders’ perceptions towards commerce subject in enhancing economic growth in Arusha city council, Tanzania
(University of Dar es Salaam, 2023-04) Makiago, Anna Elieza
The aim of this study was to explore secondary school stakeholders’ perceptions towards Commerce subject in enhancing economic growth in Arusha City Council in Tanzania. The study was guided by three objectives. Firstly, to examine teachers, students and policy makers’ views on the contribution of Commerce subject in enhancing economic growth in Arusha City Council. Secondly, to explore strategies used in teaching and learning of Commerce subject to enhance practical skills to students for economic growth. Thirdly, to explore challenges faced by teachers and students in teaching and learning of Commerce subject for economic growth. The review of the related literature discussed the context of the problem in a wider panorama. The study employed a qualitative research approach with an embedded single-case study research design. Purposive and snowball sampling procedures were employed to select participants. The sample size included 20 secondary school graduates who had commerce background in their secondary education, eight Commerce subject teachers and two education policy makers from the Ministry of Education, Science and Technology. Data collection tools include semi-structured interviews, non-participant observation and documentary reviews. Data were analysed qualitatively using the thematic analysis strategy. Findings unveiled the following. First, Commerce subject instils the skills and competencies required for practical business and management to the youths. Second, findings found that commerce subject teachers were not encouraging students to study Commerce subject which resulted to low uptake of commerce subject. Third, findings revealed that few Commerce subject teachers applied the teacher-centred strategies like lecture method instead of the learner-centred strategies such as project-based learning and field trip during teaching and learning of Commerce. Four, findings uncovered that commerce teachers were important resources in monitoring/supervising and facilitating students’ participation in different types of activities performed during teaching and learning process although they did not receive sufficient in-service trainings. The study recommends that the Ministry of Education, Science and Technology in cooperation with education stakeholders should recruit Commerce subject teachers to cater for the current needs including, in particular, to equip youths who lacked business and financial skills. Likewise, the Ministry of Education, Science and Technology should prioritise commercial studies and provide sufficient number of professional trainings to Commerce teachers to update their professional knowledge. In addition, the government should allocate adequate funds for teaching and learning resources including books in secondary schools. Finally, the study recommends an exhaustive quantitative study should be conducted to check whether or not the teaching and learning of Commerce in secondary schools reflect competence-based teaching and learning methodologies.
An assessment of the determinants of operational risk management practices in downstream oil and gas business in Tanzania: the Case of Petrol Stations in Dar es Salaam
(2023-04) Blassius, Saraphina Maggebo
The study assessed the determinants of operational risk management practices in petrol stations in Tanzania. Specifically, it aimed at examining the effect of regulatory framework, firm size and nature of the operation on operational risk management practices for petrol stations located in Dar es Salaam city. Also this study examines the moderation effect of perceived safety on the relationship between the determinants and operational risk management practices. Employing the stakeholder theory, the study collected data using questionnaires from 99 petrol stations. The data was quantified mostly in a five point Likert scale and then analyzed through multiple regression analysis. Findings, revealed that regulatory framework and firm size had negative and positive effect on operational risk management practices respectively at 5% of significance level. The nature of operation was insignificant at 5% level of significance. Further, the findings revealed that perceived safety has moderating effect between each of the determinants and operational risk management practices at significant level of 5%, as it turned the nature of operation into a significant positive effect on operational risk management practices. Therefore, study concludes that a moderator has a significant positive effect on the relationship between determinants and operational risk management practices. The study suggests that policy and practice should create positive safety perception to their staff and the stations environment because it does influence the operational risk management practices. Further studies can analyze the effect of determinants on operational risk management practices by including all petrol stations in Tanzania, using a qualitative study or a mixed approach.
Factors affecting the Tanzania national information and communication broadband backbone (NICTBB) systems restoration time
(University of Dar es Salaam, 2023-05) Chingumbe, Anifa Ally
This research investigates the factors affecting the prolonged system restoration when NICTBB services are affected by breakdown incidents. The main goal is to reduce the time taken to restore NICTBB services.
The National ICT Broadband Backbone, NICTBB, is the government owned backbone infrastructure. The NICTBB aims to increase the usage of ICT for equitable and sustainable socio-economic development and accelerate poverty reduction. Provisions of ICT services require infrastructures that are stable, reliable and available throughout their life span. Failures and outages of the infrastructure are intolerable.
The study used both primary and secondary methods in data collection. Data was collected from TTCL, Ministry responsible for communication and information technology and other Telecoms operators who are the key customers of NICTBB infrastructure. Primary data were collected using questionnaires and analyzed by factor analysis and regression analysis. The confirmatory factors analysis was performed to confirm the factors affecting NICTBB restoration time and the strategies to improve restoration time. The current restoration time was confirmed by the analysis of secondary data.
The study revealed that it takes more than six hours to restore NICTBB services. The locality and accessibility to fault location, availability and readiness of restoration team and unsatisfactory preventive maintenance services were found to prolong the restoration time. To improve NICTBB restoration time, there is a need to enhance NICTBB operations and maintenance strategy. The strategy will enable NICTBB manager to align its internal processes to prioritize NICTBB maintenance works and provide key resources including availability of funds, proper training and availability of working tools and test gears at all maintenance centers.