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Product Costing And Pricing In Small And Medium Enterprises In Tanzania, Cosmas F Kindole

Tanzania Journal of Engineering and Technology (TJET)

metalwork small and medium enterprises located in Dar es Salaam with the aim of establishing methods used by SMEs in Tanzania in setting selling prices of their products. The study was necessitated by the apparent discrepancy of prices for similar products from SMEs. The approach used to gather information was mainly through direct interview and the use of questionnaires. Direct observation and literature review were also used to establish the whole costing and pricing practices in metal manufacturing SMEs. The findings of the study established that product selling practices of the surveyed SMEs were based on instinct and appearance of …

Assessment On Usage Of The Library Website Resources By Students In The Information Studies Programme At The University Of Dar Es Salaam, Hosea N. Mungwabi

Tanzania Journal of Engineering and Technology (TJET)

The study investigated students' usage of electronic resources available on the UDSM Library's website. Specifically, the study determined whether information studies students were aware of the electronic resources, how frequently they used them, and whether their demographic characteristics influenced their usage. The study also examined the students' satisfaction with the functional and non functional attributes of the website resources. A mixed-methods research design combining both qualitative and quantitative data collection methods was used. The sample consisted of 118 student respondents who were selected using a stratified random sampling technique. The data were collected through questionnaires and interviews with class representatives …

Deep Learning Model Compression Techniques: Advances, Opportunities, And Perspective, Hubert Msuya

Tanzania Journal of Engineering and Technology (TJET)

Recently, deep learning (DL) models have excelled in a wide range of fields. All of these successes are built on intricate DL models. The hundreds of millions or even billions of parameters and high-performance computing graphical processing units or tensor processing units are largely responsible for their achievement. DL model integration into real-time devices with tight latency limitations, limited memory, and power-constrained requirements is the key driving force behind investigation of DL model compression techniques. Also, there is an increase in data availability that encourages multimodal fusion in DL models to boost the models' predictive accuracy. In order to create …

Path Of Trust: An Off-Chain Performance Enhancement Algorithm For Public Blockchains, Anthony Kigombola

Tanzania Journal of Engineering and Technology (TJET)

Blockchain technology is one among the latest innovations in computing industry. Blockchains have gathered widespread interest in the industry due to their potential as secure data storage. Despite the potential benefits of blockchains, there are several limitations which hinders mass deployment, one of these limitations being low throughput. Low throughput has limited blockchain adoption in large scale applications such as banking or mobile payments. This study addresses this limitation through development of a performance enhancement algorithm called Path of Trust (PoT). PoT uses off-chain stratergy in which transactions meeting certain criteria bypass the main chain and sent direct to the …

The Estimation Of Heavy Tails In Non-Linear Models, Josephine N. Onyeka-Ubaka, Olaide Abass

Tanzania Journal of Science

A generalized student t distribution technique based on estimation of bilinear generalized autoregressive conditional heteroskedasticity (BL-GARCH) model is introduced. The paper investigates from empirical perspective, aspects of the model related to the economic and financial risk management and its impacts on volatility forecasting. The purposive sampling technique was applied to select four banks for the study, namely First Bank of Nigeria (FBN), Guaranty Trust Bank (GTB), United Bank for Africa (UBA) and Zenith Bank (ZEB). The four banks are selected, because their daily stock prices are considered to be more susceptible to volatility than those of other banks within the …

Lipophilic Wood Extractives’ Contamination Of Water Bodies In The Vicinity Of Pulp And Paper Mill, Southern Tanzania, Shija Charles, Kessy F. Kilulya, Julius Mbuna

Tanzania Journal of Science

This paper reports on the levels of fatty acids and selected sterols in effluents and nearby water bodies at Mufindi Paper Mill (MPM), southern Tanzania. Solid Phase Extraction (SPE) was used for sample extraction, and analysis was performed using Gas Chromatography-Mass Spectrometer (GC-MS). Fatty acids ranging from C11:0 to C25:0 were detected, with saturated fatty acids (SFA) being more abundant than unsaturated fatty acids (USFA). As for selected sterols, β-sitosterol and stigmastanol were more abundant than campesterol. The mean levels of SFA, USFA, β-sitosterol, stigmastanol, and campesterol (µg/L) were 538.28, 125.94, 1065.44, 1178.01, and 66.76, respectively, for untreated effluents, and …

Influence Of Urban Land Use Land Cover Changes On Land Surface Temperature In Dar Es Salaam Metropolitan City, Tanzania: The Use Of Geospatial Approach, Olipa Simon, Nestory Yamungu, James Lyimo

Tanzania Journal of Science

Land use land cover (LULC) changes affect the planet's energy balance and region's climate. Land Surface Temperature (LST) is a vital indicator of this change. Studies in Dar es Salaam Metropolitan City have investigated LST and its relationships with building heights and densities, urban heat islands, spectral indices, and urban morphological determinants. The present study used cross-sectional profiles, chord diagrams, and simple linear regression models to examine the influence of LULC changes on the LST in Dar es Salaam Metropolitan City (DMC). LST was extracted from Landsat 5 TM and 8 OLI/TIRS images for 1995, 2009, and 2017. LULC was …

Application Of Agile And Simulation Approaches For The Maximal Benefits Of Reduced Turnaround Time From The Point Of Care Testing, Yusta W. Simwita, Berit I. Helgheim

Tanzania Journal of Science

This paper uses simulation to explore improvement opportunities in the orthopaedic care process. Secondly, this study used a combination of simulation and agile strategies to explore agile operational plans that can be adopted  to maximize the benefits of reduced turnaround time. Data used for this study was collected by observing the entire orthopaedic care process. A total of 635 observations were obtained, with 179 out of these observations undergoing the whole care process. The actual collected patient data were compared with the simulation output to validate the developed simulation. Different scenarios were developed to test operational plans for the maximal …

Thermal Performance Of A Mechanical Thermostat For Charging An Energy Storage System, Swaleh Tusiime, Karidewa Nyeinga, Denis Okello, Ole J. Nydal

Tanzania Journal of Science

Thermal energy storage (TES) systems enhance the use of solar energy for cooking by matching the energy demand to its supply. Useful energy is extracted from TES systems that are thermally stratified and this is enhanced when charged at an averagely constant-temperature. This paper presents an experimental analysis of a mechanical-thermostat used to control the charging of an oil based TES system. The thermostat consisted of a slider-valve, an expansion-system acting both as a thermal-sensor and actuator, and an adjusting-knob for setting the charging temperature. Oil from a cold-oil reservoir flows by gravity into a heating-chamber when a manual valve …

Identifying Factors Contributing To Under-Five Mortality In Nigeria, Olateju Alao Bamigbala, Ayodeji Oluwatobi * Ojetunde

Tanzania Journal of Science

The under-5 mortality rate (U5MR) is the probability that a child born in a specified year will die before turning 5 years of age. U5MR is still high in Nigeria. Therefore, this study aimed to identify factors contributing to under-5 mortality in Nigeria. The data used in this study were from the 2018 NDHS, encompassing 2013–2018. The methods of analysis used for this study were frequency, percentage, and Zero Inflated Negative Binomial (ZINB) regression. Data were analyzed using R programming v.4.1.2 and p < 0.05 was considered to be statistically significant. The result showed 35.4% under-5 mortality out of the 33,924 infant mortality sample data that were collected. The findings revealed maternal age, regions (North East and North West), maternal education (no education), wealth index (poorest households), and size of child at birth (very small birth size) as significant factors associated with under-5 mortality in Nigeria. The results also showed that the odds of under-5 mortality increase as the age of the mother increases. Therefore, the Nigerian government should understand that poverty is not just an economic problem but also a significant factor in health; as a result, the battle against poverty needs to receive the necessary attention.  Keywords:    Under-5 mortality; World Health Organization; Zero inflated distribution; Risk factors; Nigeria.

Dna Barcoding Reveals Occurrence Of Cardiocephaloides Sp. (Digenea: Strigeidae) Infecting The Great Cormorant Phalacrocorax Carbo (L. 1758) In Mwanza Gulf, Lake Victoria, Fred D Chibwana

Tanzania Journal of Science

Cormorants (Pelecaniformes) are widely distributed worldwide, occurring as coastal birds in inland waters and marine environments, and have been implicated in the transmission of some aquatic parasites. As such, the objective of the present work was to investigate the occurrence and morphological variations in Cardiocephaloides (Digenea: Strigeidae), parasites of the great cormorant Phalacrocorax carbo. The Cardiocephaloides specimens used for molecular analysis (DNA barcoding (cox1) region) were obtained from the intestines of the great cormorants collected from Mwanza Gulf in Lake Victoria. Morphological examination of Cardiocephaloides specimens showed the possible co-existence of four morphospecies belonging to the genus Cardiocephaloides. However, detailed …

The Causal Links Between Urbanization, Energy Use And Carbon Emissions: A Case Of Sadc Region, Pendo T Kivyiro

Tanzania Journal of Science

The study aimed at examining the causal links between urbanization, energy consumption and carbon emissions in the case of selected SADC countries. The study employed annual time series data spanning from 1988 to 2020 extracted from the World Bank Development indicator Databank. A Pedroni cointegration test was employed to test whether the variables of interest move together in the long run. Granger causality backed with Full Modified Ordinary Least Squares (FMOLS) was used to detect the direction and the nature of causality among the variables of interest. The results from Pedroni cointegration test revealed that the variables move together in …

A Review Of Theropithecus Oswaldi With The Proposal Of A New Subspecies, Dagmawit Abebe Getahun, Eric Delson, Chalachew Mesfin Seyoum

Publications and Research

Theropithecus oswaldi darti, as currently understood, is the oldest Theropithecus taxon in the fossil record and the earliest subspecies in the Theropithecus oswaldi lineage. Theropithecus oswaldi darti is typified at the site of Makapansgat in South Africa, and a similar form (T. o. cf. darti) is usually recognized at Hadar, Dikika, some Middle Awash localities, and Woranso-Mille in Ethiopia. This taxon is also tentatively believed to occur in Kenya at Kanam and Koobi Fora and in Member C of the Shungura Formation in Ethiopia. While there is a general consensus that the East African ‘darti’ specimens are …

Agricultural Shocks On Household Stability: A Case Study Of Tanzania Maize Farmers, Zimmi Silonda Ndlovu

Master's Theses

As the global populations grow, the need for stronger agricultural resilience in areas with high food insecurity like Sub-Saharan Africa (SSA) is a must. Crop failure due to climate related events has increased substantially over the past decade, raising the risks to vulnerable groups like subsistence farmers. Understanding the effects of climate variability on farmers and their crops is a pivotal step towards increasing resilience and productivity. In this paper I approach this question using a Linear Probability Fixed-effects Model on Tanzanian Panel Survey data with monthly temperature and precipitation for years 2008 to 2013. Results suggest a negative relationship …

Integrated Neutrosophic Best-Worst Method For Comprehensive Analysis And Ranking Of Flood Risks: A Case Study Approach From Aswan, Egypt, Safa Al-Saeed, Nabil M. Abdelaziz

Neutrosophic Systems with Applications

This paper presents a comprehensive framework for the analysis and ranking of flood risks with respect to regional variations and data uncertainties under a Neutrosophic environment. The research introduces a novel approach to flood risk mitigation and management, bringing together the scientifically robust Best-Worst Method (BWM) and single-valued Neutrosophic set for the first time. The unique application of a single-valued Neutrosophic set allows us to better illustrate and manage uncertainty, imprecision, and vagueness in data. Additionally, we employ BWM, a multi-factor decision-making method, for discerning and ranking the most influential flood risk factors. Together, the integrated methodologies provide a balanced, …

The State Of Accessibility In Blackboard: Survey And User Reviews Case Study, Mohamed Wiem Mkaouer, Wajdi Aljedaani, Stephanie Ludi, Mohammed Alkahtani, Marcelo M. Eler, Marouane Kessentini, Ali Ouni

Articles

Context: Nowadays, mobile applications (or apps) have become vital in our daily life, particularly within education. Many institutions increasingly rely on mobile apps to provide access to all their students. However, many education mobile apps remain inaccessible to users with disabilities who need to utilize accessibility features like talkback or screen reader features. Accessibility features have to be considered in mobile apps to foster equity and inclusion in the educational environment allowing to use of such apps without limitations. Gaps in the accessibility to educational systems persist.

Objective: In this paper, we focus on the accessibility of the Blackboard mobile …

A Cloud Based Model Symbiotic Organism Search Algorithm For Placement Of Distributed Energy Resources In The Electrical Secondary Distribution Networks, Shamte Kawambwa, Daudi Mnyanghwalo

Tanzania Journal of Science

Abstract The increased penetration of distributed energy resources (DERs) technologies to residential users has fostered the need for DERs integration and control methods in the secondary distribution networks (SDN). In order to reap the potential advantages of DERs and achieve their inclusion in the electrical power system while avoiding their negative impacts, the DERs should be optimally placed and sized. Considering the nature of electrical networks and DER operations, the DERs placement is a nondeterministic polynomial hard (NP-hard) optimization problem. Metaheuristic algorithms are efficient for solving DER placement problems. Metaheuristic algorithms for DER placement in SDN involve high computational effort, …

Generation Of Electricity By Using Microbial Fuel Cell Prototype Fed By Sewage: Case Study At The University Of Dar Es Salaam, Mahir M Said, Asia A Saad, Geoffrey R John, Aviti T Mushi

Tanzania Journal of Science

The access to electricity is still not reliable in Tanzania. Whilst, there are several locations within the country that have wastewater cites that are not economically used to produce electricity. At the University of Dar es Salaam (UDSM), there are main grid power, and few scattered solar panels. This study was intended to bridge the divide between the current increasing power demands of the UDSM by exploiting not so much used sources, such as electric energy from wastewater. This study was undertaken to develop a Microbial Fuel Cell (MFC) prototype fed by sewage in Dar es Salaam, for electricity generation …

Adsorption Of Water Vapour On The Microstructure And Stability Of Cu-Zn Bimetallic Coordination Polymer, Bukunola K. Oguntade, Gareth M. Watkins

Tanzania Journal of Science

A current challenge in the design of synthesis lies in the incorporation of two or more transition metals into a coordination polymer. The most widely used approach has been to incorporate a second metal as a generally innocent (coordinatively saturated) part of a linear linker as in the case of multifunctional carboxylated porphyrins (MCPs). The empirical method has been used to obtain many other types of MCPs; however, the selective, direct replacement of one transition metal within a monometallic coordination polymer via controlled stoichiometry has not generally led to maintained structural fidelity. In this present work, three pyromellitic acid complexes …

Semi-Analytic Approach To Solving Rosenau-Hyman And Korteweg-De Vries Equations Using Integral Transform, Adedapo Chis Loyinmi, Kabir Oluwatobi Idowu

Tanzania Journal of Science

In this research, we proposed the fusing of Elzaki transform and projected differential transform (PDTM) to obtain an analytical or approximate solution of the Rosenau-Hyman and Korteweg-de Vries equations which respectively govern pattern formation in liquid drops and model of waves on shallow water surfaces. The results obtained presented in tables and graphs showed better efficiency, accuracy, and convergence of the method to handle Rosenau-Hyman and Korteweg-de Vries equations when compared to other methods in the literature. Keywords:          Rosenau-Hyman Equation; Korteweg-de Vries equation; Elzaki Projected differential transform method; Semi-analytic approach

Potential Of Kaolin Clay On Formulation Of Water Based Drilling Mud Reinforced With Biopolymer, Surfactant, And Limestone, Paul M. Omary, Emanuel X. Ricky, Naswibu A. Kasimu, Makungu M. Madirisha, Kessy F. Kilulya, Esther H. J. Lugwisha

Tanzania Journal of Science

Drilling the wellbore into subsurface formations is the earliest stage in the life of a well that requires a suitable drilling fluid with good rheological and filtration control characteristics to achieve a successful drilling operation. This paper reports on the formulation of water-based drilling mud using kaolin clay reinforced with biopolymer, surfactant, and limestone from Tanzania. The raw materials used for the formulation were characterized using XRD, XRF, FTIR, and TGA techniques. The rheological properties, filtration loss, pH, and density of the formulated mud were measured using a viscometer, filter press, pH meter, and mud balance, respectively. The XRD results …

Effects Of Climate Change, Land Use And Land Cover Variability On Green And Blue Water In Wami/Ruvu Basin, Tanzania, Benson Hm Lazaro, Martine M Hagai, Rubhera Ram Mato

Tanzania Journal of Science

Water basins are the primary food sources, giving green water and blue water worldwide. Despite the basins’ potential, information on the periodical variations in blue water and green water is sparse, particularly in developing countries. The study specifically evaluated the changes in land use and land cover variability (LULCV), effects of land use and land cover variability on green water and blue water variations, and effects of climatic changes on green water and blue water. The evaluation involved the Enhanced Thematic Mapper and Operational Land Imager satellite images of 1990, 2000, 2010 and 2020. Image processing utilized the Soil and …

Spatial And Temporal Solar Potential Variation Analysis In Uganda Using Measured Data, Daniel N Katongole, Karidewa Nyeinga, Denis Okello, Daniel Mukiibi, James Mubiru, Yeeko Kisira

Tanzania Journal of Science

The paper presents an analysis of spatial and temporal solar potential variations in Uganda. The solar radiation potential distribution was investigated based on measured data from 56 ground meteorological stations across Uganda from January 2015 to February 2022. The data were recorded after every 5-minute interval. The monthly average daily Global Horizontal Irradiance (GHI) was analysed using the spatial inverse distance weighting (IDW) interpolation technique in ArcGIS 10.7.1. The GHI distribution was found to have maxima at equinox and minimum between June and July. The average global horizontal irradiation is found to be 1680 KWh per year, with a daily …

Simulation Of Mathematical Model Of Network Interference On Global System For Mobile Communication, Yidiat O. Aderinto, Yusuf Musa

Tanzania Journal of Science

Network interference is the incorporation of undesirable signals to desirable ones in an interconnected system. In this paper, the simulation of mathematical model of network interference with respect to global system of mobile communication is presented. The model was formulated and analyzed mathematically. Numerical simulation was carried out using real life data from Communication Towers Nigeria Limited, Northwest regional office Kaduna, Nigeria. The results obtained were very close to that of laboratory investigation. Keywords: Mathematical Model, Network, Interference, Congestion, Mobile communication, Stability

Short-Term Energy Load Forecasting Model With Sample Filtering, Ruthbetha Kateule, Lucas A. Sakala, Mahadia Tunga

Tanzania Journal of Science

Short-term energy load forecasting is a crucial task in the power smart grid, which enables the power utilities to understand the future energy demands and plans to attain the demand and supply equilibrium, thereby optimizing power deployment and reducing power losses. Several techniques have been implemented to enhance energy load forecasting. However, the nonlinear nature of the data collected in the smart grid makes it difficult to attain 100% energy load forecasting accuracy. For instance, the Deep Feedforward Neural Networks model based on Input Attention Mechanism and Hidden Connection Mechanism has a mean absolute percentage error of 3.17%; model based …

Geo-Statistical Analysis Of Meteorological Drought And Recurrence Intervals In The Context Of Climate Change Over Extreme Northeastern Region Of Nigeria, Iliya B. Abaje

Tanzania Journal of Science

This study examined the occurrence of meteorological drought in the context of climate change over the extreme northeastern region of Nigeria using rainfall and temperature data spanning a period of 60 years (1961-2020) and 40 years (1981-2020), respectively. Linear regression, 5-year moving average and Cramer’s test were used to examine the changes in the rainfall and temperature. Rainfall Anomaly Index was used in depicting periods of different drought intensities in the region. The trend analysis of the climate data revealed that the region has been experiencing increasing rainfall and temperature in recent years. Findings also revealed that the droughts of …

Maintenance Scheduling Algorithm For Transformers In Tanzania Electrical Secondary Distribution Networks, Hadija Mbembati, Kwame Ibwe, Baraka Maiseli

Tanzania Journal of Science

The drive by the government of Tanzania to electrify every village has resulted into expansion of the electrical secondary distribution networks (ESDNs). Therefore, maintenance management is of the highest priority for the smooth operation of the ESDNs to reduce unscheduled downtime and unexpected mechanical failures. Studies show that condition-based predictive maintenance (CBPdM) method allows the utility company to monitor, analyze and process the information obtained from ESDNs transformers. Thus, this study adopts the CBPdM method to develop a maintenance scheduling algorithm that can predict the transformer state, forecast maintenance time based on transformer load profile and schedule its maintenance using …

Evaluation Of Image Enhancement Techniques For Electrical Capacitance Tomography Applications, Alfred J Mwambela

Tanzania Journal of Science

The fast generation of images in Electrical Capacitance Tomography (ECT) systems is a desirable feature for many industrial applications. Non-iterative reconstruction algorithms which qualify for this requirement generate poor-quality images. The Linear Back Projection (LBP) is the fastest non-iterative reconstruction algorithm. The challenge is to find a technique to improve the quality of images from LBP at a low computational cost. Image enhancement techniques have been investigated for improving the quality of images reconstructed from the LBP algorithm. Simulated and measured static and dynamic flow data were used in the evaluation. The performance results were benchmarked with results from the …

Measurement Of Solar Irradiance For Determining The Optimal Tilt Angle For Photovoltaic Panels, Gbadebo I. Olatona, Tolulope J. Fadairo

Tanzania Journal of Science

The challenge of solar panel installers in determining the tilt angle needed to obtain optimal performance from the photovoltaic panels was the focus of this paper. The performances of two 150 W panels under varied conditions of temperature and solar irradiance on a plane at two different heights (1 m and 11.5 m) from the ground surface were determined to find the effects of tilt angle and altitude on their performances. Measurements of solar irradiance, temperature, open-circuit voltage, and short circuit current were made at various tilt angles and compared to one another based on the measured irradiance. The optimal …

A Mathematical Algorithm Approach For Estimating Water-Based Paint Requirements For A Given Wall, Ismail W. R. Taifa Dr

Tanzania Journal of Engineering and Technology (TJET)

The research aimed to improve the accuracy of estimating water based paint requirements for a given wall using mathematical algorithms. The approach used in this study included a survey and document review to obtain details concerning paint. The study focused on water-based paints, including silk, weather guard, emulsion hi-cover and polyvinyl acetate (PVA) roof paint used in Tanzania’s building and construction industry. Data collected from the field study were analysed systematically. It was observed that there is a high level of familiarity in improving the accuracy of estimation of the required water-based paints, namely silk, weather guard, emulsion hi-cover and …