Department of Mathematics, Statistics and Computational Sciences

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Analysis of contents of Tanzanian university library websites
(2014-11) Sife, Alfred S; Tandika, Zabron
A study was carried out between January and February 2013 to analyze the contents of 16 university and university college library websites in Tanzania using content analysis method. The consolidated data were analyzed using Microsoft Excel and presented in tabular form. The study findings revealed that although many university library websites have some commonalities, these websites miss many important features. Some library websites have very little content that do not provide a real picture about their collections, resources and services. The websites also lack uniformity despite many similarities that university libraries possess. There is poor presentation of details on e-resources and library services. It is recommended that the design of library websites should be driven by the information needs and seeking behaviour of target users rather than technology or library functions. Website designers should make use of current and emerging technologies to provide library users with opportunities to locate and retrieve information efficiently. Furthermore, library websites should be updated regularly in order to respond to users’ changing needs. Recommendations on future research are also provided.
Barriers to adoption of sustainable agriculture practices among farmers in Tanzania, case study of Mbarali district
(World Wide Journal of Multidiscip linary Research and Development, 2018) Msemo, Emanuel; Sayi, Soleji; Kazuzuru, Benedicto
Current conventional agriculture systems of production lead to environmental degradation, economic problems, and even social problems. Despite having support from change agents, farm organizations, conservation organizations, or environmental groups, Commercial firms or dealerships, farmers in Tanzania are seldom adopting sustainable agriculture practices. This study was set to examine social economic factors influencing/hindering a farmer’s adoption of sustainable agriculture in Mbarali district of Mbeya region in Tanzania. A binary logistic regression model was used to analyze such factors. It was established that the closer the farmer is from town, a farmer having training in agriculture, a farmer having an off farm income and a farmer having a huge farm are having positive influence on a farmer adopting sustainable agriculture. On contrary, a farmer being young does not motivate him to adopt sustainable agriculture. Nevertheless the finding on a farmer’s age still needs further investigation as some literature suggests this not to be the case. It is therefore recommended to the government and other stakeholders to encourage farmers to have off farm incomes by providing credits and market access so as to motivate sustainable agriculture.
Determinants of inbound tourism demand in Tanzania.
(Sokoine University of Agriculture, 2013-05) Kazuzuru, Benedicto
The study investigates the determinants of inbound tourism demand both at macro and micro levels. At macro level the study investigates the determinants of the number of tourist arrivals, while at micro level the study investigates the determinants of the per capita expenditure of tourists, their length of stay and their choice of a package tour. In achieving the first objective, panel data regression analysis was employed using the number of arrivals obtained from the Ministry of Tourism and Natural Resources (1995-2007) as well as a number of covariates from different sources. Regarding the determinants of tourists’ per capita expenditure, an OLS was applied on a cross-section of tourists surveyed in the years 2001, 2007 and 2008. As for the length of stay, a survival analysis was employed, whereas for the choice of a package tour a binary logistic regression was used, in each case using the cross-section data of the years 2001, 2007 and 2008. Among the key findings is that non price factors (such as the country’s economic development) are more influential than price factors in attracting tourists to Tanzania. Trip-related characteristics of the tourists such as purpose of visit and the number in travel party were found to be the most influential variables in explaining tourists’ daily spending, length of stay and choice of package tour. To promote the number of arrivals it is implied that the government should invest more in the non-price factors such as infrastructure whereas to enhance micro demand, promotion organs and other stakeholders should attune their marketing strategies more to trip-related characteristics of the tourists than to other factors.
Developing pre-service mathematics teachers’ understanding of metric and topological spaces using reflective questions .
(IOJET., 2021) Deogratias, Emmanuel
This paper presents the ways that reflective questions were used to develop pre-service mathematics teachers’ understanding of metric and topological spaces. In particular, the purpose of developing PSTs’ understanding of metric and topological spaces is that understanding these mathematical concepts leads to PSTs’ understandings on how to teach and learn geometrical figures in mathematics classes after completion of their degree programs. This paper details the interpretation of the PSTs’ reflections on metric and topological spaces. From PSTs’ reflections, it was found that reflective questions helped individual PSTs to develop their understanding of matric and topological spaces, including giving the meaning of metric and topological spaces, and relating with real objects available in their daily environment. The findings have implications in teaching and learning metric and topological spaces.
Effect of E × B drifts in convective zone
(Cambridge University Press, 2004) Callebaut, Dirk K.; Karugila, Geoffrey K.; Makarov, Valentin I.
The E × B drift allows plasma to move through the magnetic field lines and may contribute to various motions inside the Sun (e.g. to explain the adverse gradient of differential rotation in the equatorial zone), at its surface and in the corona. Here we treat an example: using a given azimuthal angular frequency ω(r, θ), rather arbitrary, and the corresponding exact solution for B, we obtain E and the drift velocity. The latter is comparable with the original velocity, but has components in all directions
Effects of navier slip and wall permeability on entropy generation in unsteady generalized couette flow of nanofluids with convective cooling
(U.P.B. Sci. Bull, 2015) Mwizu, Michael H; Makinde, Oluwole D.; Nkansah-Gyekye, Yaw
Present work investigates the effects of generalized Couette flow with convective cooling, Navier slip and permeable walls on entropy generation in an unsteady of water based nanofluids containing Copper (Cu) and Alumina (Al 2 O 3 ) as nanoparticles. Both first and second laws of thermodynamics are applied to analyse the problem. The nonlinear governing equations of momentum and energy are solved numerically using a semi discretization finite difference method together with Runge-Kutta Fehlberg integration scheme. Graphical results on the effects of different parameter variations on velocity, temperature, skin friction, Nusselt number, entropy generation rate, and Bejan number are presented and discussed.
Enhancing pre-service teachers’ understanding of a mathematical concept through practises: a constructivist perspective
(Research Gate, 2022-07-22) Deogratias, Emmanuel
This paper addresses the ways that Tanzanian university pre-service mathematics teachers (PSTs) practised teaching the concept of pi in a daylong research meeting. The research meeting focused on enhancing the PSTs’ understanding of a mathematical concept through practises. In particular, the activities were designed and implemented based on practise as one of the five components of the concept-rich instruction (CRI). The intention in using the activities based on practise was to enhance PSTs’ pedagogical knowledge and skills through participating in designing and performing micro-teaching for teaching the concept while using local circular objects as teaching and learning resources. Nine PSTs volunteered to participate in this study. The PSTs worked in small groups while designing the lesson plans and performing micro-teaching. Audio-video recordings and group learning notes were used to collect qualitative data in the research meeting. The collected data were analysed using thematic analysis while focused on the ways that PSTs practised related to the concept. NVIVO software was used in the coding process (QSR international Pty Ltd. Version 11.4, 2017). It was found that the activities helped PSTs to enhance their understanding on how to teach pi as a concept, including designing the lesson plans for teaching the concept using local circular objects, performing micro-teaching and demonstrating measuring the diameter and circumference of a circular object using a set of vernier callipers, a string and a ruler. These findings have implications in the teaching and learning of mathematics in university mathematics classes, including PSTs can gain pedagogical knowledge and skills on how to engage learners in a participatory way of learning as well as learning by doing. Keywords: A mathematical concept; pi, practises, pre-service mathematics teachers, instructional activities
Factors limiting livestock based entrepreneurships in Tanzania: a case of livestock training agency (LITA) graduates
(Sokoine University of Agriculture, 2022) Chassama, Alphonce Lucas
The study was conducted to investigate the factors limiting entrepreneurship among livestock professionals. It draws empirical data and evidences from Livestock Training Agency (LITA) graduates in order to identify factors limiting them in establishing livestock based enterprises. The sample comprised of 122 LITA graduates obtained through snowball sampling technique and six (6) key informants including owners of viable livestock-based enterprises, LITA campuses, Farm Managers, and District Officers in Local Government Authority. Data were collected using a questionnaire and key informant interview checklists. Chi-square test and independent sample (t-test) were used to test the characteristics of respondents in relation to engagement in livestock enterprises. Descriptive analysis was conducted to examine perceptions, to assess attitudes of LITA graduates, and to analyze challenges and constraints encountered in running livestock based enterprises. Multiple logistic regression analysis was carried out to enable inference making on the relationships between entrepreneurship in livestock sector and other factors. The study found that attitudes such as individual fear for failure and unwillingness to take risks limit entrepreneurship in livestock sector to a greater extent, followed by lack of confidence in entrepreneurships and inability to capitalize available business opportunities in livestock sector. It was further discovered that perceptional factors limit entrepreneurship in livestock sector to a moderate extent. Dedicated initiatives are required in counteracting the major impeders in order to promote entrepreneurship in livestock based enterprises. However, providing support such as credit loan will help LITA graduates in starting as well as expanding viable livestock businesses. It is therefore important for the government and other stakeholders to ensure that LITA graduates are provided with adequate support to deal the identified factors that potentially limit entrepreneurship in livestock based enterprises.
Internet of things to improve agriculture in sub sahara Africa - a case study
(IJASRE, 2018-06) Ishengoma, F.; Athuman, M.
Agriculture is the main source of income in many countries in sub-Sahara Africa (SSA). In these countries, farmers get less yield because they depend on rainfall only. Integrating Internet of Things and Agriculture (smart agriculture) helps farmers to grow more crops in any season of the year. Also, it improves farmer’s living standard and raises the economy of these countries. Moreover, it reduces labor work or manual work which takes more time and more cost. This paper is evaluating the areas where smart farming can be applied in agriculture and brings the direct impact to farmers in SSA
Investigation of effect of rock storage system parameters on thermal cooling performance
(Science Publishing Group, 2016-01-15) Matofali, Alex Xavery; Massawe, Estomih S.
We investigate the effects of key parameters of the rock bed system on thermal cooling performance of the system after a fixed time of operation. The method of solving the mathematical model uses a semi-discretization finite difference approximation for discretizing space in solid problem domain. A finite element approximation is used in the fluid problem domain. Graphical results on the effects of parameter variation on damping and time delay on the peaking of the outlet air temperature through the bed are presented and discussed.
Modeling the impact of vertical transmission in vectors on the dynamics of dengue fever
(World Academic Union, 2017-06-27) Nyerere, Nkuba; Matofali, Alex X.; Mpeshe, Saul C.; Edward, Stephen
Dengue is a viral illness caused by infection with one of four dengue viruses known as dengue 1, 2, 3 and 4. In this paper we develop a deterministic mathematical model for dengue fever with vertical transmission in female aedes aegypti mosquitoes. The basic reproduction for the model is computed. Sensitivity analysis of the basic reproduction number for the model indicates a direct relationship between basic reproduction number and vertical transmission rate. To reduce or eradicate dengue fever in the community, public health workers should focus on an intervention that destroys most of the aedes aegypti mosquitoes and their eggs. Moreover, numerical simulation shows that, the spread of dengue fever is very fast and therefore needs precautions and immediate and serious attention after epidemic.
Modelling the in-human host and in-mosquito dynamics of malaria parasite and effect of therapy
(Nelson Mandela African Institution of Science and Technology, 2017) Selemani, Mohamed Abdallah
In this study, a basic mathematical model for the in-human host and in-mosquito dynamics of malaria parasite is formulated. A positive invariant region of the model was established, and a basic reproduction number 7vo, of the model was computed. Conditions for existence and stability of two equilibrium points: malaria free equilibrium (MFE) and malaria infection equilibrium (MIE) were established. The impacts of model parameters on control of malaria infection were assessed through the sensitivity analysis of TZ q . Despite having lower sensitivity index compared to death rate of merozoites. and death rate of schizonts have greater impact on malaria control than that of merozoites. The model was extended to incorporate the effect of immune responses using nonlinear bounded Michaelis- Menten-Monod functions to describe how immune responses interact with infected cells and parasites. Our results revealed that immunity has significant influence on reducing malaria infection at erythrocytic and sporogonic stages, but not at exo-erythrocytic stage. We further extended the model to incorporate the antimalarial drug therapy, where four thera peutic classes of antimalarial drugs in various stages of entire life cycle of malaria parasite are included. In contrast to the immunity whose effect reduces infections on only two stages, drug therapy has the effect of reducing infection on all stages of the life cycle. Although its compo nents do not appear in the expression of reproduction number, tissue schizonticidal drugs reveal a substantial effect on reducing the infection at each stage of malaria life cycle. This study suggests that a combination therapy with all four classes of antimalaria! drugs should be developed because of its prolific effect on controlling malaria, and for such case, an artemisinin derivatives-primaquine combination therapy is proposed.
Multipath protections and dynamic link recovery in softwarized 5G networks using segment routing
(2020-03) Barakabitze, Alcardo Alex; Sun, Lingfen; Mkwawa, Is-Haka; Ifeachor, Emmanuel
Future softwarized 5G networks have to be robust enough so as to ensure high network reliability and services availability. 5G network architecture should make sure that any failed parts in the network are detected, restored and recovered within a permissible period of time and at the lowest achievable cost. In this paper, we propose a Multipath Protection and Link-Failure free MPTCP/SR-based SDN/NFV architecture that increases survivability, resilience, availability of services in 5G net- works. We present our system model and a multiPath protection and dynamic Link- Failure free algorithm called ”PathReLief” that greatly reduces the failure recovery time and avoids link congestion in MPTCP/SR SDN/NFV 5G networks. To demonstrate the effectiveness of our proposal, we compare the performance of the proposed algorithm and the conventional topology discovery mechanisms for link/node failures in POX and OpenDaylight con- trollers. Preliminary results show that, our approach outperforms others used in the commonly used controllers (i.e., POX and OpenDaylight), in terms of reduced failure recovery time and localization time.
Numerical investigation of entropy generation in unsteady MHD generalized Couette flow with convective cooling
(Communication in Mathematical Modeling and Applications, 2019-12-31) Kigodi, O.; Mkwizu, M. H.; Matofali, A. X.; Selemani, M. A.; Ainea, N.; Khamis, S.; Karugila, G. K.
This study aimed at making an investigation on entropy generation in unsteady MHD generalized couette flow with convective cooling. Specifically the study intended to; develop flow model for a case of nanofluid in a channel, determine the effect of different parameters on velocity, temperature and entropy generation and to determine the effect of magnetic field on the flow on an entropy generation. Also the study aim to come up with distinctively recommendation on dynamics of entropy generation, temperature variation and velocity profiles in unsteady MHD flow with convective cooling. Findings showed that an increase in nanoparticles and Reynolds number leads to increase in the velocity while pressure gradient, MHD and nanofluid fraction held constant. It is evidently that Alumina-water nanofluid tends to raise the velocity profile faster than Copper-water nanofluid. Also the results show that an increase in Eckert number causes the decrease in temperature profile. Further, it was noticed that Copper-water nanofluid tends to raise the temperature profile faster than Alumina-water nanofluid. More interestingly it was observed that the entropy generation rises as the result of increase in Eckert number. Also it is noticed that entropy generation rises in lower plate but when it comes closer the upper plate the entropy generation rate starts to fall as the result of increase in nanoparticles.
On Vladimirov’s approximation for ideal in homogeneous MHD
(2005-08) Callebaut, D. K.; Karugila, G. K.; Khater, A. H.
Vladimirov and Vladimirov and Moffat have considered configurations in ideal magnetohydrodynamics, i.e. inviscid and perfectly conducting. The matter is considered as incompressible. However, the density is allowed to vary slowly. They base the following approximation on this slow variation: they omit the mass density in front of the total derivative of the velocity in the equation of motion. Normally the mass density should appear in front of Du. This is a tremendous simplification which allows them to obtain various interesting results concerning the stability of the configurations. However, in such a kind of approximation the results might be only crude. However, in many applications the results are OK, because crucial in those papers is the vanishing of ∇ρ × ∇φ. Often both gradients are parallel and the results obtained by Vladimirovs approximation are nevertheless valid, e.g. in the application to inhomogeneous gas clouds and protostars. Moreover for small density gradients and/or nearly parallel gradients the approximation is fair. We even suggest an approximation which may be more correct and avoids the term ∇ρ × ∇φ. Hence for linear perturbations and stability analyses the results may turn out to be acceptable. However, for nonlinear stability a more extended analysis is required.
Optimal control analysis of a cholera disease transmission model in Tanzania
(IJSRSET, 2018) Ainea, Neterindwa; Matofali, Alex Xavery; Mkwizu, Michael
In this paper, a deterministic model with optimal control of cholera in Tanzania is proposed and analysed. Necessary conditions of optimal control problem were rigorously analysed using Pontryagin's maximum principle and the numerical values of model parameters were estimated using maximum likelihood estimator. Two control strategies were incorporated such as human education campaign and treatment of water (to reduce the growth of the organism) and its' impact were graphically observed. The goal is to minimize the spread of cholera disease in the community and to minimize the costs of control strategies. The results show that the effective use of optimal human education campaign and treatment of water has a significant impact in reducing the spread of the disease in the community.
Optimization of thermal cooling Parameters applied to rock Storage systems
(2015) Matofali, Alex Xavery
This study presents a mathematical model for thermal energy storage in low energy buildings. The cooling system which uses rock bed for storing night cooling to be used later for daytime air conditioning is presented. The work initially focuses on the mathematical descriptions of the thermal cooling applied to rock storage system. A numerical method of solution is outlined and the results are compared with measured data at the outlet of the bed both using the measured inlet temperature. A good agreement of trend is observed. The results show two effects of the cooling system on the air temperature, which are damping and time delay of the peaking. The differences are examined through sensitivity analyses for both the convective heat transfer coefficient and mass flow rate. A parametric study for heat storage with materials and bed size is given. A genetic algorithm (GA) is used as a tool to identify the thermal cooling system parameters related to the mathematical model, including the radius of the sphere (rocks), mass flow rate, convective heat transfer coefficient and length of the rock bed. The simulation results have shown an improvement on the performance of the model with identified parameters compared to the performance before parameter optimization. In general, the model with optimal parameters has shown robustness to predict the performance of the cooling system by reducing the input (air) temperature as much as possible at the time when the temperature is hottest.
Population change and food availability in Tanzania; a multilevel modeling approach: the case of Ukerewe Islands
(University of Dar es salaam, 2005-08) Malogo, Deogratias Solole
Primary data from a survey of 150- rural households in Ukcrewe district, one of the densely populated rural districts in Tanzania mainland, were used to examine the relationship between socio-demographic variables and household food availability. The study employed the Principal Component Analysis (PCA) in the construction of households’ possession indices which was then used as the proxy determinant of food availability. The 2-level random intercept model with 3-ordered categorical response variable was used in the estimation of coefficient of effects. The findings show that household seasonal migrants, education attainment by household members, farm land resources and life cycle of household at different stage of development that was measured by the age of household head, were significant. It was further noted that seasonal migrants and farm land were likely to reduce the odds ratio of a household of being extremely poor or poor. An increase of a person with secondary or post-secondary education in a household reduced the odds ratio of a household of being extremely poor by 52.8 percent as compared to 19 percent odds ratio reduction by increase of non educated household member. The findings show that the young aged head of household was 3 and 5 times less likely to be extremely poor as compared to old and middle age headed household respectively. The data could not allow any viable conclusion to be drawn from variables such as; household sex ratio, sex of household head, size of the household and proportion of household permanent migrants because they were statistically insignificant
Powerfull nonlinear plasma waves from moderate first order perturbations
(2005-08) Callebaut, D. K.; Karugila, G. K.
The nonlinear Fourier method of Callebaut consists in concentrating on the family of higher order terms of a single Fourier term of the linearized analysis. Thus we have obtained the higher order terms of plasma perturbations, gravitational ones, etc. In the simplest case of cold plasma this resulted in obtaining an analytical expression for the higher order terms. This allowed to investigate the convergence of the series, which in this case limits the first order amplitude to 1/e of the equilibrium density. For the cases without an analytical expression we developed a numerical-graphical method to obtain the convergence limit. Near this limit the total amplitude of the wave becomes very large. The convergence limit decreases with increasing pressure. Thus a wave with moderate first order amplitude may carry a very large energy due to the higher orders. Moreover, this energy is concentrated in a very narrow interval of the phase interval (0, 2π). This may be relevant in many situations. E.g. in the case of ball lightning a tremendous energy may be accumulated while the glowing is still restricted. The triggering of solar flares or coronal mass ejections may thus be caused. Again, when these eruptions reach the Earth the influence of a first order term may be far too small to cause electric power plants to break down; however, the total of all terms may be much more powerful. Cf. March 1989 when the whole state of Quebec, Canada, was a day without electricity due to a solar storm. This is an alternative mechanism from the one proposed by Callebaut and Tsintsadze based on soliton envelope formation, although there the accent was on the heating of the plasma.
The role of social networks as survival strategies in agro-pastoral communities in arid and semi-arid lands in Tanzania
(Asian Economic and Social Society, 2017) Rusomyo, R.; Junlin, H.; Mangare, C.
Agro-pastoral communities in semi-arid areas of Tanzania are among the most food insecure groups in the country. In the absence of precisely stipulated mitigation measures from the government the agro-pastoralists have, all across their history relied on social networks for their survival. This paper seeks to examine in detail the role of social networks as survival strategies in coping up with food insecurity among agro-pastoral communities in Arid and semi-arid areas of Tanzania. Based on data and information that was collected through focus group discussions and in-depth interviews in three villages of Sejeli, Mtumba and Makoja it is reported that social networks have been significant in sustaining livelihoods of vulnerable households. These traditional social networks are based on mutual trust and organized on consanguine and kinship ties and through these networks wealth and riches are shared by the agro-pastoral communities. The findings further reveal that these traditional social networks do better than the externally induced initiatives. It has also been revealed that, despite facing a myriad of challenges such as competition for labor, lack of entrepreneurial skills and negative impacts of commercialization of livelihoods on food security the traditional social networks are surviving albeit with hitches. It is recommended that policy interventions that seek to construct resilience of the vulnerable households need to consider traditional systems of social networking.

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