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Data driven approach for predicting student dropout in secondary schools
Get PDFA Thesis Submitted in Fulfillment of the Requirements for the Degree of Doctor of
Philosophy in Information and Communication Science and Engineering of the Nelson
Mandela African Institution of Science and TechnologyStudent dropout is among the challenges that face most schools in developing countries
particularly in Africa. In Tanzania alone, student dropout in secondary schools is pronounced
to be around 36%. In addressing the student dropout problem, a thorough understanding of the
fundamental factors that cause the student dropout is essential. Several researchers have
identified and proposed causes, methods and strategies that will help to reduce or stop the
student dropout problem, however, most of the proposed solutions didn’t show promising
results and the students dropout trend continue to increase over time. This study focused on
developing a data driven approach that will help to identify and predict students who are at risk
of dropping out of school in order to facilitate an intervention program as an active measure in
eliminating the problem of dropout in Tanzania. In doing so, (a) 122 research articles were
examined, (b) 4 focus group discussions and 2 round table surveys with 38 respondents from
5 districts (Arusha, Mbeya, Kisarawe, Rufiji and Nzega) were conducted, and (c) 3 datasets
from Tanzania and India were used in order to identify factors that contribute significantly to
student dropout problem, disclose the best classifier from the commonly used classifiers
(Logistic Regression, Random Forest, K-nearest Neighbor and Multilayer Perceptron) and
assessing the data balancing techniques for predictive performance of the model. Results
revealed that, most of the respondents mentioned students’ gender, age, parent’s income,
number of qualified teachers and remoteness as the main contributing factors to the students’
dropout problem in secondary schools. Furthermore, results from the examined articles
indicated that, most studies conducted in developing countries focused on the social aspects of
student dropout, and a paltry mentioned the use of other approaches such as machine learning.
Nevertheless, results from data driven approach development shows that the Logistic
Regression and Multilayer perceptron achieved the highest performance when over-sampling
technique was employed. Also, the hyper parameter tuning improved the algorithm's
performance compared to its baseline settings, and stacking of the classifiers improved the
overall predictive performance of the developed approach. The study, therefore, recommends
the developed approach to be considered by relevant authorities in identifying and predicting
students at risk of dropping out for early intervention, planning and informative decisions
making on addressing the student dropout problem
The distribution, control techniques and impact of Parthenium hysterophorus on flower visitors and soil chemical properties in Meru district, Tanzania
Get PDFA Dissertation Submitted in Partial Fulfilment of the Requirements for the Degree of
Doctor of Philosophy in Life Sciences of the Nelson Mandela African Institution of
Science and TechnologyIn Tanzania, the invasive plant Parthenium hysterophorus threatens natural and semi–natural
environments. Little is known about how this species affects plant–pollinator interactions and
soil–chemical properties. Roadside survey was conducted to assess P. hysterophorus invasion
status within and outside Arusha National Park (ANP), Tanzania. Soil samples were also
collected in invaded and uninvaded plots to investigate the impact of P. hysterophorus on
soil–chemical properties. To test alternative natural–based management strategies, the study
examined the bio–herbicide potential of Desmodium uncinatum leaf (DuL) crude extract and
the competitive ability of fodder legume plant species (Lablab purpureus, Desmodium
intortum and Medicago sativa) to suppress P. hysterophorus in pot and plot experiments.
Results showed that ANP is currently uninvaded with P. hysterophorus, but some adjacent
villages i.e. King’ori, Maleu, Napoco, Ngongongare, Ngurdoto, Oligilai and Sakila have
already invaded by this invasive. Parthenium hysterophorus invaded site was more acidic
with lower electrical conductivity, less calcium and phosphorus, and high cation exchange
capacity. The DuL extract suppressed P. hysterophorus growth vigour, particularly at higher
concentrations (>70%). At these concentrations, the invasive seedling stem height was >30%
shorter, and seed germination was inhibited by >55% compared to seedlings sprayed with
lower concentrations. When P. hysterophorus was grown in combination with all three test
plants, its seedling stem heights and total fresh biomass were reduced by >60% and >59% in
pots, and >40% and >45% in field plots respectively, compared to when grown alone or in
mixture with just D. intortum or M. sativa.
Moreover, surveys conducted on invaded and uninvaded sites to investigate the impact of P.
hysterophorus on plant–pollinator interactions when two common target plants (Ocimum
gratissimum and Ageratum conyzoides) were present showed that flower visitation rate to
target plants was significantly lower in invaded plots than in uninvaded plots. This implies
that P. hysterophorus may be disrupting pollen flow. The study recommends that the use of
bio–herbicide and suppressive plant species to control the invasive should be promoted.
However, it emphasizes the use of native suppressive plant species because non–natives may
turn into invasives in the future
Detection of Contagious Caprine Pleuropneumonia and Concurrent Diseases in Outbreaks Presenting with Respiratory Signs in Small Ruminants in Tanzania
Get PDFThis research article published by the International Journal of TROPICAL DISEASE & Health, 2020Aims: To establish the prevalence and concurrent diseases in outbreaks presenting with respiratory signs, major associated clinical signs and postmortem lesions and proportions of those diseases in clinically and autopsied small ruminants for a proper diagnosis and control strategies.
Study Design: Purposive outbreaks investigation.
Place and Duration of Study: Department of Global Health, School of Life Science and Bio-Engineering (LiSBE), Nelson Mandela Institution of Science and Technology (NM-AIST) between September 2016 and December 2018.
Methodology: We included investigations of outbreaks of diseases presenting with respiratory signs in small ruminants reported from five agro-ecological zones in Tanzania. Small ruminats with clinical signs or postmortem lesions suggestive of respiratory involvement were subjected to clinical or postmortem examination. Samples from all examined animals were tested in the laboratory using conventional polymerase chain reaction (PCR) to confirm the tentative diagnosis.
Results: A total of 205 small ruminats were examined and tested, of these 72.2% and 20.8% were goats and sheep respectively. In goats, 79.1% (117/148) and sheep, 28.1% (16/57) were confirmed to have concurrent infections, and pneumonic pasteurellosis and peste des petits ruminants (PPR) for goats, and PPR for sheep being mostly involved diseases. Contagious caprine pleuropneumonia (CCPP) was detected in 16.1% (n=205) of the animals, and was significantly high in goats (p=0.003, OR=7.3) than sheep. Pneumonic mannheimiosis (prevalence = 9.3%) was less likely to affect goats than sheep (p=0.047, OR=0.38). In goats (n=148), detection of all diseases was significantly (p<0.05) low in clinically examined animals except pneumonic pasteurellosis and PPR, (p =0.056, OR=2.1) and (p=0.096, OR=2.15) respectively, though the difference was not significant. In sheep (n=57), CCPP was significantly (p=0.005, OR=0.17) more likely to be detected in clinically examined animals.
Conclusion: In investigations of outbreaks presenting with respiratory signs in small ruminants, it is important to consider concurrent infections in the interventions and control strategies to be deployed, which may include development and use of multivalent vaccines
A Framework for Implementing an Education Management Information System in Tanzanian Secondary Schools to Improve Delivery of Quality Education and Students’ Academic Achievement
Get PDFThis research article published by Modestum, 2020Globally, access to quality education is being recognized by educational scholars as a significant process of poverty eradication. In developing countries including Tanzania, access to quality education is a national goal supposed to be achieved by Tanzania Development Vision 2025. However, the practice is being hindered by the use of manual systems in administering academic activities in secondary schools. The manual systems lead to loss of data integrity, work productivity of teachers, inefficiency and ineffective collection, and dissemination of educational information required to support education policymakers in planning, monitoring, and evaluation of quality educational activities. This study used structured interviews and questionnaires to collect data from educational stakeholders of the Arusha region to investigate a cost-effective digital solution required to improve the delivery of quality education for sustainable development. After data analysis, findings revealed that Tanzanian secondary schools required to use a centralized education management information system in administering schools’ academic activities. The study concluded by formulating a cost-effective digital framework that can enhance the accurate and timely collection and dissemination of quality educational information for supporting planning, monitoring, and evaluation of the academic activities. Due to the tremendous change of technology, this study recommended all schools to adapt to the use of digital tools rather than manual systems in administering schools’ academic activities
Biovar 2 of Ralstonia solanacearum Species Complex Causes Tomato Bacterial Wilt Disease in Tanzania
Get PDFThis research article published by Science Alert, 2020Background and Objective: Bacterial wilt disease (BWD) caused by complex species of Ralstonia solanacearum (RSSC) has been
categorized as one of the most significant plant diseases in the world. It is a serious problem of tomato and causes significant
economic losses of tomato in Tanzania. The purpose of this study was to determine biovars of RSSC causing tomato BWD in Tanzania.
Materials and Methods: Tomato stems showing typical symptoms of BWD were collected from main agro-ecological regions and were
characterized by pathological and carbohydrate oxidation tests. The least significance difference (LSD) procedure was used for mean
separation (p = 0.05) of disease incidence and severity. Results: A total of 29 out 40 RSSC isolates from infected tomato stems produced
typical colonies of RSSC on triphenyl tetrazolium chloride medium out of which 19 (52%) were pathogenic on tomato variety Tanya.
Carbohydrate oxidation test showed that most (90%) predominating isolates in main agro-ecological regions belong to biovar 3 while
the rest (10%) belong to biovar 2 and prevail in the southern zone of Tanzania. This is the first report of prevalence of biovar 2 of Ralstonia
in Tanzania and suggests a recent introduction of biovar 2 in tomato fields in Tanzania. Conclusion: Biovar 2 of RSSC is reported for the
first time to cause tomato bacterial wilt disease in Tanzania. This alerts plant health regulators to embark on necessary phytosanitary
measures to prevent further spread and/or introduction of the disease considering its quarantine status in different countries
Gaseous complex hydrides NaMH and NaMH (M = B, Al) as hydrogen storage materials: a quantum chemical study.
Get PDFThis research article published by Springer Nature Switzerland AG., 2020Metal hydrides are feasible for energy storage applications as they are able to decompose with hydrogen gas release. In this work, gaseous complex sodium hydrides, NaMH and NaMH (M = B or Al), have been investigated using DFT/B3P86 and MP2 methods with 6-311++G(d,p) basis set; the optimized geometry, vibrational spectra and thermodynamic (TD) properties have been determined. Based on TD approach, a stability of the hydrides to different dissociation channels is analysed; the enthalpies of formation ∆H°(0) of gaseous species have been obtained: - 1 ± 17 kJ mol (NaBH), 91 ± 14 kJ mol (NaAlH), - 13 ± 16 kJ mol (NaBH), and 71 ± 16 kJ mol (NaAlH). The complex hydrides are confirmed to produce gaseous products with hydrogen gas release at elevated temperature, whereas heterophase reactions, with NaH and B/Al products in condensed state, are predicted to occur spontaneously at lower temperature. Graphical abstract
Adequacy of micronutrient fortification in the mandatory fortified food vehicles in Tanzana
Get PDFThis research article published by Emerald Publishing Limited, 2020Purpose
This study aims to update the information on the current status of micronutrient fortification for iron, zinc, folic acid and vitamin A in mandatory fortified food vehicles such as cooking oil, wheat and maize flours in Tanzania.
Design/methodology/approach
A cross-sectional study was conducted in five regions to analyze the adequacy of micronutrient fortification in mandatory fortified food vehicles. Samples of fortified edible oil (n = 19), wheat flour (n = 12) and maize flour (n = 5) were sampled conveniently from local markets and supermarkets. Samples were analyzed for vitamins (vitamin A and folic acid) and mineral (iron and zinc) content using high-performance liquid chromatography and microwave plasma-atomic emission spectrometer, respectively. Compliance acceptable ranges between the minimum and maximum levels for each nutrient were used as a basis for compliance.
Findings
The results showed that 83.3% and 80% of wheat and maize flour samples, respectively, complied with iron fortification standards (p = 0.05). Only 25% of wheat flour samples and 40% of maize flour samples were within the acceptable ranges for zinc fortification (p = 0.05). Nearly 17% and 20% of wheat and maize flour samples, respectively, were within the acceptable ranges for folic acid fortification (p = 0.05). Moreover, about 10.5% of the analyzed cooking oils were adequately fortified with vitamin A (p = 0.05). Except for iron in wheat and maize flours, the levels of other micronutrients in mandatorily fortified foods were out of acceptable ranges.
Originality/value
Mandatory fortification is still far from the established standards, and this calls for a review of the current fortification strategies regarding standards, training, monitoring and enforcement in Tanzania
Early identification of Tuta absoluta in tomato plants using deep learning
Get PDFThis research article published by Elsevier B.V., 2020The agricultural sector is highly challenged by plant pests and diseases. A high–yielding crop, such as tomato with high economic returns, can greatly increase the income of small- holder farmers income when its health is maintained. This work introduces an approach to strengthen phytosanitary capacity and systems to help solve tomato plant pest Tuta ab- soluta devastation at early tomato growth stages. We present a deep learning approach to identify tomato leaf miner pest ( Tuta absoluta ) invasion. The Convolutional Neural Network architectures (VGG16, VGG19, and ResNet50) were used in training classifiers on tomato image dataset captured from the field containing healthy and infested tomato leaves. We evaluated performance of each classifier by considering accuracy of classifying the tomato canopy into correct category. Experimental results show that VGG16 attained the high- est accuracy of 91.9% in classifying tomato plant leaves into correct categories. Our model may be used to establish methods for early detection of Tuta absoluta pest invasion at early tomato growth stages, hence assisting farmers overcome yield losses
Memoir and Farming Structures under Soil-Less Culture (Hydroponic Farming) and the Applicability for Africa: A Review
Get PDFThis research article published by ARCC JOURNALS, Volume 41, Issue 2, 2020Agriculture is the economic back-borne of majority of developing countries worldwide. The sector employs over 50% of the working population and contributes about 33% of the Gross Domestic Product (GDP) in majority of African states. However, such contribution by the agricultural sector is likely to be affected by climate change, increasing human population and urbanization which impact on available agricultural land in various ways. There is thus an urgent need for developing countries to create or adopt technologies such as; soil-less farming that will not only address climate change challenges but also enhance crop production for improved food security. This paper reviews the science, origin, dynamics and farming systems under the soil-less agriculture precisely hydroponic farming to assist in widening the scope of knowledge of the hydroponic technologies and their implementation in Africa
A Deterministic Mathematical Model for the Control of Spread of Prosopis Juliflora Plants
Get PDFThis research article published by Journal of Mathematics and Informatics Vol. 19, 2020Prosopis juliflora plants are the most aggressive invasive species in the world.
They spread by animal movement crossing from one place land to another. In this paper a
deterministic model to examine the dynamics of Prosopis julifrola plants is formulated and
presented by adopting a similar approach of a dynamical system as used in epidemiological
modeling. The local and global stability analyses of the equilibrium points of the model
performed by using next-generation for the basic reproduction number R0
computation and
Lypunov function method. The finding from the study showed that the Prosopis free
equilibrium of the model is both locally and globally asymptotically stable if and only if
the number of secondary infections, is less than unit, that is R0 < 1. Furthermore, the study
showed that there exist Prosopis endemic equilibrium for the spread when 0 R >1. The
numerical simulation implemented in MATLAB ODE45 algorithm for solving linear
ordinary differential equations. The study findings showed that as the number of ingested
animals increase, the plant spread increases on land. Based on the findings, the study
recommend the application of the model on endemic areas to improve through: Awareness
on animal feeding the plant, provision of insight on plant invasion to policy makers and
environmental stakeholders to include in environment framework, seminars and
environment clubs by visiting community groups an educating them on plant invasion,
through this the plant eradication could be achieved