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Invisible waste: Understanding the political culture of solid and liquid waste management in towns of Tanzania
Get PDFThis research article was published INNSPUB in 2022This article uses ethnographic and case study approaches to unveil the distinct culture characterising the
management of liquid and solid waste in urban areas of Tanzania. The article shows that slow accumulation
nature of liquid waste such as faecal sludge makes it of less immediate nuisance to residents compared to solid
waste, and the general public tend to perceive the management of liquid waste as a responsibility of individual
dwelling owners hence a private good rather than public good that would require organisation at a community
level. This makes liquid waste less visible to politicians and residents alike despite it being a higher risk factor for
disease outbreaks compared to solid wastes. The article argues that attempts to improve liquid waste
management need to focus on making it a political priority by creating demand driven service provision, where
residents would increase political pressure for access to improved liquid waste management services
Effect of Lactic Acid Fermentation on Volatile Compounds and Sensory Characteristics of Mango (Mangifera indica) Juices
Get PDFThis research article published by MDPI, 2022Fermentation is a sustainable bio-preservation technique that can improve the organoleptic
quality of fruit juices. Mango juices were fermented by monoculture strains of Lactiplantibacillus
plantarum subsp. plantarum (MLP), Lacticaseibacillus rhamnosus (MLR), Lacticaseibacillus casei (MLC),
Levilactobacillus brevis (MLB), and Pediococcus pentosaceus (MPP). Volatile compounds were sorbed
using headspace solid phase microextraction, separated, and identified with gas chromatography mass spectrometry. Forty-four (44) volatile compounds were identified. The control, MPP, and MLB
had higher amounts of ethyl acetate, ethyl butyrate, 2-hexenal, 2,6-nonadienal, 2,2-dimethylpropanal,
β-selinene, γ-gurjunene, α-copaene, and δ-cadinene, while MLC, MLP, and MLR had higher amounts
of 2,3-butanedione and a cyclic hydrocarbon derivate. Consumers (n = 80) assessed their overall
liking and characterized sensory attributes (appearance, color, aroma, flavor, consistency, acidity, and
sweetness) using check-all-that-apply, and penalty analysis (just-about-right). Overall liking was
associated with ‘mango color’, ‘pulp’, ‘mango aroma’, ‘sweet’, ‘natural taste’, and ‘mango flavor’ that
described the control, MLB, MLC and MPP. Juices MLR and MLP were described as ‘bitter’, ‘sour’,
‘aftertaste’, and ‘off-flavor’. Multivariate analysis revealed relationships between the volatile com pounds, mango juices fermented by different lactic acid bacteria, and sensory characteristics. Thus,
the type of lactic acid bacteria strains determined the volatile and sensory profile of mango juices
Development of a mobile application for sales and marketing: a case of Raha beverages company limited
Get PDFA Project Report Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science in Embedded and Mobile System of the Nelson Mandela African Institution of Science and TechnologyRaha Beverage Company Limited is a wine-producing company based in Arusha Tanzania. It was
experienced with the challenge of products advertisement to reach more customers. The problem
extended to a lack of knowledge on market demand because there was no prior orders collection
before product delivery, also the market demand fluctuation results in either less quantity delivery
to wholesalers or delivery delay, causing wholesalers to stay out of stock for a while. Hence
decreases customer satisfaction. The proposed RahaSales mobile application was designed to
address and mitigate the encountered challenges by the company. The study showed that the
mobile application would easily connect the company with their customers for instant
communication and getting insights on the market ground. To reflect what was the exact puzzle to
be solved; the data was collected from the sales representative and known customers through
interviews, questionnaires, and observation. The mobile application was developed through the
agile method known as scrum, and then the application was tested by both customers and sales
representatives from the company to reflect what the application is required to do. The developed
mobile application connects the supplier and wholesalers to enable them to share business
information like market demand and product availability. According to the findings, mobile
applications can be used to improve client loyalty as well as sales. From the developed application,
I would like to recommend further studies to utilize the GPS locations collected from the customers
to map all customers in the Google map for easy visualization of current customers and will help
the company to determine where there is a gap in the market share and focus more in terms of
advertisement and promotions
Effects of navier slip and skin friction on nanofluid flow in a porous pipe
Get PDFA Dissertation Submitted in Partial Fulfilment of the Requirements for the Degree of Master’s in Mathematical and Computer Sciences and Engineering of the Nelson Mandela African Institution of Science and TechnologyRecent advances in cooling, filtering, heat transfer, and other processes have all focused
attention on fluid flow through porous media. During the flow partial slip becomes more
important at wall surfaces in improvement of performance of various devices. In this regard,
the governing equation has been presented for the flow of porous pipe with Navier slip in this
study also non dimensionalisation has been done. Systems of equations The governing system
was expressed to ordinary differential equations, thereafter a mathematical model for the flow
of nanofluids was developed. Results are presented graphically of various parameters having
different values on and discussed. It is found that the velocity and temperature during the flow
is inversely proportional to Navier slip also in order to overcome skin friction there is a need
to increase nanoparticles
Automated uninterruptible power supply battery protector: case study of Tanzania atomic energy commission, Arusha-Tanzania
Get PDFA Project Report Submitted in Partial Fulfilment of the Requirements for the Degree of Master of Science in Embedded and Mobile Systems of the Nelson Mandela African Institution of Science and TechnologyUninterruptible Power Supply (UPS) is electrical apparatus that provides emergency power to its
load when the input power source fails and manages power fluctuations through its battery during
power failure to allow a user to save work and shut down a system procedurally. The UPS’
electrical ability depends on its battery’s strength. At Tanzania Atomic Energy Commission
(TAEC) users mostly leave their UPS on as they go home, and when there is blackout, the UPS
batteries get drained to zero leading to a significant number of UPS getting damaged in a year.
Automated Uninterruptible Power Supply Battery Protector (AUPSBP) is developed to protect
UPS battery at the institution using Kanban Agile methodology which supported teamwork. The
AUPSBP monitors the voltage from mains to UPS using a voltage sensor. When the sensor detects
a lack of voltage from the mains to UPS, AUPSBP triggers timer counting down towards switching
the UPS off. When tested, AUPSBP switched off the UPS when the set time of 5 minutes elapsed,
and when UPS battery voltage was <100V protecting UPS battery from draining to zero during
blackout. It sent Short Messages using Global System for Mobile communication when mains
power was switched off, and when UPS was switched off before the set time of 5 minutes
elapsed. The AUPSBP is effective for switching off UPS before its battery drains to zero to prevent
battery damage on different types and sizes of UPSs with only changes in switch and timer.
Therefore, AUPSBP is needed to protect UPS at TAEC
Spatial and seasonal group size variation of wild mammalian herbivores in multiple use landscapes of the Ngorongoro Conservation Area, Tanzania
Get PDFThis research article was published by PLOS ONE, 2022Group sizes of wild herbivores can be indicators of ecosystem health and proxies for individual and population fitness, particularly in areas where human activities have become increasingly common. We recorded 176 single- and multi-species groups of wild herbivores in human-dominated landscapes of the Ngorongoro Conservation Area (NCA) during dry and wet seasons. We analyzed how wild herbivore group sizes were affected by: (1) season, (2) distance to fully protected area (NCA crater) and to streams, (3) distance to human settlements, and (4) numbers of livestock. Group sizes were generally larger during the wet season than during the dry season and varied seasonally with distance to NCA crater, streams, and human settlements. During the wet season, larger groups were observed further away from the NCA crater whereas the opposite pattern was apparent during the dry season. Average wild herbivore group sizes increased by about three-fold with increasing distance from the streams during the dry season but were invariant to streams during the wet season. Furthermore, during the dry season, group sizes were larger close to settlements but varied little with distance to settlements during the wet season. While livestock presence did not directly affect wild herbivore group size, distance to settlements, streams and distance to the Ngorongoro crater in interaction with rainfall seasonality did. We conclude that the NCA crater functions as a key resource area for wild herbivores such as wildebeest (Connochaetes taurinus) and zebra (Equus quagga burchelli) during the dry season, highlighting the need for its full protection status in this Man and Biosphere reserve
IoT based system for monitoring and controlling of electrical energy for leather industry a case study in Kenya
Get PDFA Project Report Submitted in Partial Fulfillment of the Requirements of the Award the Degree of Master of Science in Embedded and Mobile Systems of the Nelson Mandela African Institution of Science and TechnologyNowadays, most industries receive large energy consumption sheets daily, making it
challenging to monitor and control energy consumption. This suggests a need for the
development of an energy monitoring system to help observe the energy consumption behavior
and be able to make timely corrections in energy consumption. Therefore, this project aimed
to develop the electronic prototype of the monitoring and control system from an application
for a cell phone with an Android system. The energy monitoring system could help in saving
precious non-renewable sources. This project employed the agile methodology to allow for
system requirements and analysis, system development, system implementation, integration,
and testing. The information was acquired using energy consumption sensors and analyzed
based on statistical tables stored in the cloud, for four days. The sensors communicate via a
wireless network that operates on the 2.4GHz frequency, where the NRF 24 L01 + transceiver
was used. Moreover, a Raspberry pi Zero was utilized for the configuration of the central node,
and this was responsible for the collection of the information gathered in the sensors and
publishing it in the cloud every hour. For the android system-based application, the data was
collected graphically. Lastly, the developed system also produces real-time consumption data,
which were then analyzed to identify the devices with the highest consumption level relative
to the total number of devices. The information gained after the analysis of the data was also
useful in identifying any damaged equipment or machine. The damaged equipment and
machine portrayed different behaviors (they appear to be outliers) in their energy consumption
when compared to undamaged ones
Development of an evolutionary game-theoretical model for trustworthy multi-channel information gathering and dissemination system framework among fisheries stakeholders
Get PDFA Dissertation Submitted in Partial 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 TechnologyFisheries and its value added products contributes substantially in the socio-economic of
developing countries including Tanzania. Researches shows that fisheries sector contributes
4.7% and 2.4% of the Gross Domestic Product (GDP) of Kenya and Tanzania respectively.
Despite its huge contribution to socio-economic of the country, the Tanzania fisheries
stakeholders remain challenged with limited access of fisheries information, knowledge, skills
and new technologies. This challenges hinders the fisheries sector development and reduces
income to stakeholders as well as the Government. This study investigated the fisheries
information collecting and distribution among fisheries stakeholders in Mara and Mwanza
regions of Tanzania. The study examined the channels owned and used by fisheries
stakeholders to gather and disseminate fisheries information. Data were collected by
administering a survey in four (4) districts purposively selected from the two regions and 400
respondents randomly selected was involved. The data were analyzed using python panda
library and presented using bar and pie charts. Using the collected data, channel dissemination
effectiveness probability of the six channels (short Message services, Cellular phone call,
Television, Radio, mobile application, and Website) were calculated and comprehensive
analysis performed using python plotly library. Furthermore, the study developed a multi channel fisheries information management system architectural framework and a participation reputation game based incentive mechanism namely EPRIGM to encourage the fisheries
stakeholders donate truthful information and feedback. We modeled and simulated the
dynamics of stakeholder’s strategy selection using replicator dynamic concept and derive the
evolutionary stable strategies for the stakeholders. Results revealed that there is no single
channel application that fits all stakeholders and that EPRIGM ensures truthful and honest
stakeholders participation in gathering and disseminating fisheries information. In this study,
we considered only seven parameters, namely channel coverage, listening ratio, watching ratio,
channel access, average access time, information usefulness, and information sharing, in
calculating channel effectiveness probability. Lastly, the empirical results of EPRIGM
simulation revealed that all information users and information providers will choose honest
strategy to capitalize on their earnings. We do recommend further studies to consider more
factors like channel carrying capacity and channel costs in calculating channel effectiveness
probability and consider application of EPRIGM in other domain of activities
Development and Testing of Road Signs Alert System Using a Smart Mobile Phone
Get PDFThis research article was published by Hindawi, 2022Road traffic accident is a major problem worldwide resulting in significant morbidity and mortality. Advanced driver assistance systems are one of the salient features of intelligent systems in transportation. They improve vehicle safety by providing real-time traffic information to the driver. Road signs play an important role in road safety. To be effective, road signs must be visible at a distance that enables drivers to take the necessary actions. However, static road signs are often seen too late for a driver to respond accordingly. In this study, a system for alerting drivers about road signs has been developed and tested using a smart mobile phone. The study was carried out in Tanzania along an 80 km highway stretch from Arusha to Moshi town. The Haversine formula was used to measure and estimate the distance between two pairs of coordinates using the smartphone-based navigation application, Google Map. The application provides a voice alert to a needed action that enhances driver’s attention. We propose an alternative method that identifies and modifies a specific class of energy inefficiencies. According to the experimental results, the proposed methodology has the benefits of high accuracy within a user radius of 10 meters, minimum bandwidth, and low-cost application. Furthermore, the system application was secured by limiting access to the application program interface key to avoid unauthorized access to sensitive information
Mathematical modelling and analysis of deformable perturbed continuously stirred tank reactors (cstrs)
Get PDFA Dissertation Submitted in Fulfilment of the Requirements for the Degree of Doctor of Philosophy in Mathematical and Computer Science and Engineering of the Nelson Mandela African Institution of Science and TechnologyIn this dissertation, deterministic and stochastic mathematical models for a deformable per turbed continuously stirred tank reactor (CSTR) with exothermic and endothermic reactions
have been developed and analysed. The Ordinary Differential Equations (ODEs) were obtained
by using the Reynold transport theorem and Stochastic Differential Equations (SDEs) were de rived in the Ito sense from the developed classical deterministic models. There were four types ˆ
of SDEs formulation, namely, additive SDE, multiplicative SDE, parameter perturbation SDE
and transition probabilities SDE. The numerical results of the developed models were obtained
and analysed through statistical and Bayesian methods. These methods were Classical Least
Squares (LSQ) and Markov chain Monte Carlo (MCMC) for ODES while the Euler-Maruyama
technique was used to simulate the SDEs. The LSQ numerical findings showed that the mea surements fit theoretical models well provided that the noise intensity ranges between 0 and 0.5.
The MCMC results identified the parameters posterior means and the credible intervals in which
models parameters must be oscillating. The PRCCs with Latin Hypercube Sampling technique
were applied to check the sensitivity and uncertainty quantification of estimated parameters
against the models’ response. Some of the parameters of models were found to be highly and
positively correlated with models’ states and others were highly and negatively correlated with
models’ state variables. For example, seven parameters were found to be highly correlated with
exothermic CSTR model whilst six parameters were identified to be highly correlated with en dothermic CSTR model. This implies that those parameters have to be controlled and treated
carefully as the increase or decrease in their values significantly impact the models’ outcomes.
For the case of stochastic part, simulations of SDEs revealed that high fluctuations notably af fect trajectories of the variables. The overall numerical results obtained seem to be reliable and
have shown an insight in describing the dynamics of the CSTR deterministic and stochastic
models with detailed mathematical and statistical information. So, the formulated models were
analysed, validated and can be used to model and describe various mechanical, biological and
chemical processes such as filtration, anaerobic respiration and combustion among others