Faculty of Science and Technology

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Mathematical programming formulations for the examinations timetable problem: The case of the University of Dar es Salaam
(African Journal of Science and Technology, 2004) Mushi, Allen R.
Examinations Timetabling Problem (ETP) is the problem of assigning courses to be examined and candidates to time periods and examination rooms while satisfying a set of constraints. Every University has a different set of constraints and structure of examinations. Thus there is no general ETP model for all Universities around the world [1]. ETP is NP-Hard [2] and therefore no optimal algorithm is known for this problem which can solve a general problem within reasonable time. However, exact methods can be used to provide a benchmark for the heuristic methods. There is no general model for University Timetabling Problems because the problem feature differs from one University to another. In this paper we focus in the formulation of the ETP for the University of Dar as salaam. We formulate, test and compare three Integer Programming models. It is concluded that, although exact methods cannot give a solution to a real-size problem, these models give a good benchmark for testing the performance of other approaches. This paper also gives a direction for better exact models for the University of Dar es salaam’s ETP.
Tabu search heuristic for university course timetabling problem
(African Journal of Science and Technology, 2006) Mushi, Allen R.
In this study we have addressed the NP-Hard problem of academic course timetabling. This is the problem of assigning resources such as lecturers, rooms and courses to a fixed time period normally a week, while satisfying a number of problem-specific constraints. This paper describes a Tabu Search algorithm that creates timetables by heuristically minimizing penalties over infeasibilities. The algorithm is developed with special focus on the University of Dar-assalaam and compares the results with a previous manually generated timetable. It has been found that, the Tabu Search technique gives better results given a careful selection of parameters.
A closer look on conceptual modeling of trust to develop trustman system
(International Journal of Computer Science, 2011) Msanjila, Simon Samwel
Designing comprehensive trust models and mechanisms to address challenges related to mediating business oriented collaboration among organizations has become a fundamental focus of research on trust and particularly those focused on organizational Trust Management (TrustMan) Systems. Despite recent achievements from research addressing the modeling of trust, there are still insufficient generic and customizable models, mechanisms and tools to support emerging requirements on inter-organizational trust analysis. Most available model solutions supporting trust analysis are limited to: a specific application case (e.g. multi-agent systems), known actors (organizations or individuals), or domain of study (e.g. health domain). These solutions are also limited to some specific set of trust criteria applied to their development such as a small set of trust criteria for analysis of rational trust in organization. In this article we advocate that a large number of elements must be properly specified and modeled to comprehensively cover the trust objectives of organizations towards developing a supportive TrustMan system. This article analyzes and proposes three specific modeling formalisms that best represent trust relationships among organizations and presents some examples for those formalisms. It also analyzes classes of models of inter-organizational trust, namely: hard models, soft models and semi-soft models.
Optimization model for solid waste management at Ilala Municipal, Tanzania
(Journal of Informatics and Virtual Education, 2011) Lyeme, Halidi A; Mujuni, Egbert; Mushi, Allen R.
The existing solid waste management system at Ilala Municipal suffers from the lack of a real plan for collection centre locations and vehicle routes. In this study, a proposed mathematical model for municipal solid waste management process for Ilala municipality is presented. It includes the use of the concept of collection centres. Operational research methodology particularly Mixed Integer Programming is used to model the problem. The problem is solved to optimality which provides the best distribution of collection centres and their capacities. The solution shows a leastcost transportation plan with a cost saving of 38.3% per day compared to the current system.
Two phase heuristic algorithm for the university course timetabling problem: The case of University of Dar es Salaam
(Tanzania Journal of Science, 2011) Mushi, Allen R.
University course timetabling is the problem of scheduling resources such as lecturers, courses, and rooms to a number of timeslots over a planning horizon, normally a week, while satisfying a number of problem-specific constraints. Since timetabling problems differ from one institution to another, this paper investigated the case of the University of Dar Es salaam, based on the combination of Simulated Annealing (SA), and steepest descent in a two-phase approach. Solutions have been generated which greatly outperform the manually generated ones. Furthermore, the method compares well with previous work on Tabu Search but with faster execution time and higher quality on rooms allocation. It is concluded that the approach gives good results given a careful selection of parameters.
E-government adoption in developing countries: Trends in the use of models
(ESARBICA Journal, 2011) Komba, Mercy Mlay; Ngulube, P.
Like the evaluation of all other information systems initiatives, the evaluation of e-government in both theory and practice has proven to be important and complex. The importance of e-government evaluation is due to the enormous investment put in by governments for delivering e-government services and to the considerable pace of growth in the field of e-government. However, despite the importance of the evaluation of e-government services, the literature shows that e-government evaluation is still an immature area in terms of development and management. The main aim of this article is to explore various theories and models which have been used in the developing countries context to evaluate e-government adoption. Developing countries suffer from poor citizen utilization of egovernment initiatives. An assessment of various theories and models for e-government adoption in developing countries may positively contribute to enhancing government understanding of the factors that influence citizen utilization of e-government systems. Moreover, the understanding of these models can be used as means for providing valuable feedback for the planning of future egovernment initiatives in the developing countries.
Cultivating recognition: a classic Grounded Theory of E-Learning providers working in East Africa
(University of Cape Town, 2012) Tossy, Titus
The purpose of this thesis is to identify and examine the main concern amongst e-learning providers tasked with e-learning activities (design, delivery, implementation, etc.) in East Africa, including Tanzania, Kenya and Uganda. In this study the Classic Grounded Theory research methodology was used in order to identify the main concern of e-learning providers in these countries. In the course of repeated encounters with e-learning providers, this study found the concept of “Cultivating Recognition” to emerge as the main concern or core variable amongst these e-learning providers. The core variable within the Classic Grounded Theory research method is the main entity that accounts for most of the variation in the data. The e-learning providers were shown to be continually striving to resolve the issue of how to cultivate recognition from those who sponsor and monitor the projects with which they are tasked. Without proper recognition from their various stakeholders, the e-learning providers were unable to successfully deliver e-learning programs to the targeted learners. The research discovered that there were two key sub-core variables that enabled the "Cultivation of Recognition": "Legitimizing" and "Credentializing". The process of "Legitimizing" involves convincing the e-learning stakeholders that the e-learning programs and projects will be delivered in a timely, valid and sustainable manner. "Credentializing” aims to enhance the stakeholders' belief in the e-learning provider’s competence prior to the start of the e-learning project, given that sponsors and stakeholders would be unwilling to commission a project if they believe an e-learning professionals ability to deliver in terms of both financial and operational quality parameters is in question. In addition to the findings, two main implications emerged from the research. Firstly, for those working within the context of e-learning delivery within East African countries, it is not sufficient for e-learning providers simply to possess or demonstrate a high level of technical competence. They need also to be trained and mentored in how to cultivate the recognition of potential stakeholders before they canvas for e-learning projects. Secondly the possibility exists for career academics in any discipline to enhance their own research funding prospects by mastering the process of Cultivating Recognition.
Optimal portfolio management when stocks are driven by Mean-Reverting Processes
(University of Dar es Salaam, 2012) Mbigili, Lusungu Julius
In this work, we present and solve the problem of portfolio optimization within the context of continuous-time stochastic model of financial variables. We consider an investment problem where an investor has two assets, namely, risk-free assets (e.g. bonds) and risky assets (e.g. stocks) to invest on and tries to maximize the expected utility of the wealth at some future time. The evolution of the risk-free asset is described deterministically while the dynamics of the risky asset is described by the geometric mean reversion (GMR) model. The controlled wealth stochastic deferential equation (SDE) and the portfolio problem are formulated. The portfolio optimization problem is then successfully formulated and solved with the help of the theory of stochastic control technique where the dynamic programming principle (DPP) and the HJB theory were used. We obtained very interesting results which are the solution of the non-linear second order partial deferential equation and the optimal policy which is the optimal control strategy for the investment process. So far we have considered utility functions which are members of hyperbolic absolute risk aversion (HARA) family, called power and exponential utility. In both cases, the optimal control (investment strategy) has explicit form and is wealth dependent, in the sense that, as the investor becomes more rich, the less he invests on the risky assets. Linearization of the logarithmic term in the portfolio problem was necessary to be undertaken for making the work of obtaining the explicit form of the optimal control much simple than it was expected.
On IT enabling of business process reengineering in organizations
(Trans Tech Publications Ltd, 2012) Sungau, Joseph Joseph; Msanjila, Samwel
Business Process Reengineering (BPR) is a management approach used to improve organizational performance through restructuring production activities of the core services for the purpose of enhancing their efficiency and effectiveness. Although BPR improves the efficiency of processes, it can hardly be applied in its own and thus it needs to be complemented with other concepts from other disciplines. Information technology (IT) tools are seen as accuracy and effective enabler of BPR approach in restructuring activities. This paper focuses on analyzing on how IT can be an enabler of BPR approach to restructuring processes in an organization for the purpose of enhancing the effectiveness and efficiency of processes. It presents the roles of IT in BPR for organizations. It also presents challenges on organizations when implementing the BPR.
Factors for e-government adoption: Lessons from selected African countries
(UNISA Press, 2012) Komba, Mercy Mlay; Ngulube, P
This article discusses various problematic issues of providing access to, and promoting the wider utilisation of government information as important factors in e-government adoption. The Tunisian, Mauritian and Egyptian e-government experiences are examined in this article in order to highlight both good practices and remaining challenges in e-government adoption. Some of the good practices that we can benefit from, may be summarised as: formulating a viable national information and communication technology strategy (ICT-based) for modernising the telecommunications infrastructure, developing a regulatory framework for the deployment of a digital economy, obtaining international cooperation in ICT, developing skilled human resources management in ICT, developing a national digital culture in order to overcome the problems of low individual usage and adoption of ICT, establishing an information infrastructure to connect the various local government authorities, and establishing security standards in order to address threats. The study concludes that overcoming the obstacles of providing access to, and promoting the wider utilisation of government information, remain some of the biggest challenges for any government planning to adopt and implement e-government.
Pricing barrier options when the dynamics of the prices are driven by the Mean Reverting Process
(University of Dar es Salaam, 2013) Komunte, Masoud
This dissertation considers a problem of pricing barrier options when the dynamics of the asset prices (X(t)) are driven by the mean reverting process, the market/asset price X(t) is obtain from mean reversion model and a Black-Scholes PDE model for pricing barrier options under mean reversion model is obtained upon using It ˆ o formula. Through the Homotopy Analysis Method (HAM) the price of the chosen barrier option (up􀀀and􀀀out European call) that satisfies the Black-Scholes PDE model was determined. Thus, through HAM we can determine approximated prices of barrier options when the dynamics of the prices are driven by the mean reverting process (Liao, 2004). Lastly the analysis is conducted to observe the behaviour of the option price when value of one parameter increases while the value of the other two parameters remain constant. The analysis shows that the option price tends to increase with the increase of the value of the parameter for the case of volatility and degree of mean reversion while for interest rate the option price decreases when interest rate increases. In all cases it is observed that early exercise is better than late exercise to owner of the option since the option price tends to decrease as time increases also to minimize risk owner of the option should exercise the option when the volatility of the market become large. It is recommended that in future, areas of interest for research related to this study are; first, finding the option price by using direct integration after obtaining a reflection principle which is useful in determining the joint distribution of the It ˆ o integral and secondly, finding the price which is a closed form solution by using Laplace transform.
A model for predicting food security status among households in developing countries
(International Journal of Development and Sustainability, 2013) Mbukwa, Justine N.
Food security prediction has been challenging aspects in developing countries particularly in African countries such as Tanzania. Consequently, government lack proper stimulated information that is necessary in making decision on efforts required for stabilizing food situation and status in their countries. Scientifically it has been observed in research and practical that this is caused by lack of proper mechanisms, tools and approach suitable for modeling and predicting food status among households. This paper proposes a logistic regression based model for analysis and prediction of food security status. The proposed model is empirically test using practical data collected from one district in Tanzania.
The influence of Business Process re-engineering on Service Quality: Evidence from Service Industry in Tanzania
(Interdisciplinary Studies on Information Technology and Business (ISITB), 2013) Sungau, Joseph Joseph; Ndunguru, Philibert C.; Kimeme, Joseph
Problem Statement: In today’s business environment, customers are focusing on getting quality services that meet their expectations. Poor quality services lead to loss of customers, and this is particularly so with service industry. Therefore, service organizations need to offer services that delight customers. Improved business has been reported to be associated with dramatic improved service quality. Despite documented potentiality, there are mixed empirical results, findings and conclusions regarding the benefits of BPR on service quality. Therefore, this paper aimed at assessing and explaining the effects of BPR and service delivery speed on service quality. Methodology: The study used cross-sectional survey design to investigate the effect of BPR on service quality. Intensive literature review enabled to construct structural measurement model, formulate testable hypotheses and to operationalize constructs. In total ninety-five (95) service organizations participated in the study. Results: Results of the study reveal that BPR positively directly and indirectly affects service quality. In the indirect effect, it was found that BPR positively affects delivering speed which in turn affects service quality. Therefore, from these finding, it has been revealed that BPR has significant positive effect on both service quality and delivering speed. Conclusion: BPR influences both service quality and delivery speed of service organizations in of Tanzania. Based on the results, findings and conclusions from this study, it is recommended that service organizations should have concrete plans when adopting BPR techniques, which are considered key to improved service quality. In that way, service organizations will provide services that delight customers.
Business process re-engineering: the technique to improve delivering speed of service industry in Tanzania
(Independent Journal of management & production, 2013) Sungau, Joseph Joseph; Ndunguru, Philibert C.; Kimeme, Joseph
Problem statement: Delivering speed is very critical in today’s business environment. In most cases, service organizations and customers are sensitive to time spent at delivering or receiving a service. Therefore, service organizations must change in order to meet this challenge. Overtime, service organizations have worked hard to identify techniques that enhance service delivering speed for improved performance. Business process re-engineering is one of such techniques that improves business processes; including delivering speed. However, despite documented advantages, most organizations are reluctant to adopt the technique. Purpose: The paper aims at determining the effect of business process re-engineering on delivering speed; enabling organizations to appreciate the performance improvement that is associated with the technique. Methodology: The study used cross-sectional survey design to investigate the effect of BPR on delivering speed. In order to undertake the study, intensive literature review was undertaken to operationalize the constructs and to formulate the hypothesis which was tested after the field work. In total ninety-five (95) service organizations participated in the study. Results: From the study, it is revealed that BPR significantly and positively improves delivering speed of service organizations. Conclusion: For improved delivering speed, service organizations should adopt BPR technique to improve business processes for provision of delighting services to customers.
Business process re-engineering: The technique to improve delivering speed of service industry in Tanzania
(INDEPENDENT JOURNAL OF MANAGEMENT & PRODUCTION (IJM&P), 2013) Sungau, Joseph; Ndunguru, Philibert C.; Kimeme, Joseph
Problem statement: Time spent by customers at a service organization is very critical in today’s business environment. Service organizations must change to provide services to customers within the minimum time possible. Business process re-engineering is one technique that improves business processes. However, despite documented advantages, most organizations have not adopted the technique. Purpose: The paper aims to determine and explain the effect of business process re-engineering on delivering speed for enhanced organizational performance. Methodology: The study used a cross-sectional survey design that included a sample of ninety-five (95) service organizations. Focused intensive literature review enabled to construction structural measurement model, formulation of testable hypotheses and operationalization of constructs. Results: From the study, it is revealed that BPR positively improves delivering speed of service organizations. Conclusion: The adoption of the BPR technique for improved business processes enhances delivery speed in service organizations.
Some Aspects of Correlation of Physical Capital and Infrastructures on Household Food Security: Evidence from Rural Tanzania
(Journal of Economics and Sustainable Development, 2014) Mbukwa, Justine N.
To achieve the first Millennium Development Goals is still a challenge. The problem of poverty in the context of hunger still persists in Tanzania. Household’s members have not sustainable access to enough and quality of food. The major objective of this study is to ascertain whether exists some aspects of correlation between physical capital and infrastructures on the households` food security. This study was carried out in rural part of Tanzania, in Mvomero district covering three villages selected randomly (a total sample 0f 382 households). Data analysis was done using SPSS version 15.0. Chi-square test was adopted for plausible analysis assesses the extent to which some correlation exists between food security status of the households against independent variables (physical capital and infrastructures of the households). 2 χ = 6.963; − p value Based on the data analyzed empirically, it is remarkable by evidence that variables such as pesticides ( = ( 2 χ = 13.343; − p value = food security in the study area. 0.008 ), tractors ( 2 χ = 0.000 10.024; − p value = 0.002 ) and electricity ) were found to be statistically significant correlated with household’s In view of these findings, there is a need to pay attention supporting rural farmers’ to be able to access farm inputs because of existing some correlation with the household food security status. Finally, this study recommends further study to be carried by incorporating advanced statistical model such cluster analysis, principal components and factor analysis which deals with large data for plausible and interpretable findings.
Modelling the adoption of mobile payment system for paying examination fees in Tanzanian major cities.
(International Journal of Computing & ICT Research, 2014) Tossy, Titus
This paper examines the different factors affecting the intention to use the mobile payment systems for examination fee payment in the National Examination Council of Tanzania (NECTA). Using Structural Equation modelling technique from a Tanzanian major cities perspective, the paper examines whether the mobile payment systems technology acceptance level is affected by the factors affecting the intention to use. The rationale for the investigation stems from the fact that while more than 61% of Tanzanians own or have access to mobile phones and the mobile usage in major cities increases, there is decrease of NECTA candidates who opt mobile examination fee payment method. The paper attempts to model the individual intention to use mobile payment systems for paying examination fees in Tanzania major cities. It concludes that the factors that had significant impact on the individual intention to use mobile payment systems, performance expectance, social influences and trust is necessary.
Modelling the adoption of mobile payment system for primary and secondary school student examination fees in developing countries: Tanzanian experience
(International Journal of Information Technology and Business Management, 2014) Tossy, Titus
This paper examines the Use of Mobile Phones for Examination Fees Payment among Primary and Secondary School Students. The paper analyses whether there are factors affecting the use of mobile payment systems for examination fee payment. The rationale of this study is based on the fact that most scholars claim that while number of mobile phones ownership, access and usage in primary and secondary school student’s increases, there is decrease of who opt mobile examination fee payment method. From the perspective of primary and secondary school exam candidates in Tanzania, this paper used Structural Equation modelling technique to examine whether the mobile payment systems technology acceptance level is affected by factors affecting the mobile phone uses. The study identified three significant factors: performance expectancy, social influences and trust.
Investigating factors influencing the adoption and use of Free and Open Source Software (FOSS) in Tanzanian higher learning institutions: towards an Individual-Technology-Organizational-Environmental (ITOE) framework
(International Journal of Research in Business and Technology, 2014) Kisanjara, Simeo; Tossy, Titus
This paper is located within the global debates about adoption and use of Free and Open Source Software (FOSS) in developing countries. From the Tanzanian Higher Learning Institutions (HLIs), this paper investigates factors influencing the adoption and use of the FOSS. The rationale for the investigation stems from the notion that Tanzanian HLIs is yet to fully adopt and use FOSS, despite huge investments and efforts being made on ground. This is facilitated by the lack of clear FOSS adoption and use framework. The source of this data was a questionnaire which comprised of structured questions, using a five-point Likert Scale. The population sample for the study was all HLIs stakeholders in Tanzania. Participants included both public and private HLIs. The positive factors include autonomy for code modifications, IT staffs and decision makers, organization awareness, trustworthiness of FOSS, licensing and scalability, collaboration and knowledge sharing, collaboration on international ICT, organization policy and good social economic policy. The negative influences that emerged included, Lack of proper plan, low confidence, lack of expertise, unfit for purpose, difficult to implement, lack of supporting software. Furthermore, this paper motivates other researchers to analyze why the adoption and use of Free and Open source software is still low to higher learning Institutions in East Africa even though their potential benefits that have been advocated in many previous studies. Finally, the paper has proposed Individual-Technological-Organizational- Environmental (ITOE) framework for adoption and use of FOSS.
Major challenges and constraint of integrating health information systems in african countries: a Namibian experience
(International Journal of Information and Communication Technology, 2014) Tossy, Titus
This paper is located within the global debates about integrated Health Information Systems (HIS) in developing countries. From a Namibian experience, this paper examines the major challenges and constrains facing the integration of HIS. The rationale for the examination stems from the notion that the Namibia healthcare is yet to integrate the HIS, despite huge investments and efforts being made on ground. Based on own experience and backed up by a literature review, semi-structured interviews, and participant observation, major challenges and constraint in the integration of HIS and possible solutions are presented and structured. Finally the paper proposes measures within the HIS in the form of annual health provider’s workshop that could be implemented in order to share the experiences and lesson learned.

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