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Application Of Mangrove Timber In Reinforcing Concrete, John K. Makunza Jkm Sep 2023

Application Of Mangrove Timber In Reinforcing Concrete, John K. Makunza Jkm

Tanzania Journal of Engineering and Technology (TJET)

Use of mangrove timber beams for supporting floor slabs in historic buildings in Zanzibar Stone Town is still applied although the available structural data on mangrove timber is inadequate. This concern has called for an investigation on the structural properties of mangrove timber, so that the information obtained could help to establish the structural strength of the existing floor slabs in historic buildings. Hence, mangrove timber specimens were sampled from Zanzibar, and tested in the laboratory for their strengths in tension, compression and shear. The test results showed that mangrove is a hardwood timber of strength class D70, the highest …


A Multitask Learning Framework For Pilot Decontamination In 5g Massive Mimo, Crallet Victor Sep 2023

A Multitask Learning Framework For Pilot Decontamination In 5g Massive Mimo, Crallet Victor

Tanzania Journal of Engineering and Technology (TJET)

Reference signals enable the acquisition of channel state information (CSI) for purposes such as channel estimation, beam selection, precoding, and symbol detection in 5G massive multiple-input multiple output (MAMIMO) systems. Eventually, as more and more users and cells are added, orthogonal reference signals become few which leads to pilot contamination. Pilot contamination limits the performance and occurs when non-orthogonal reference signals occupy time-frequency resources that are alike. Learning-based techniques have been proposed to alleviate it. However, each can only learn to perform a single task namely pilot assignment, power allocation, pilot design, or de-noising for pilot decontamination. In addition, each …


Effects Of Bacillus Thuringiensis, Beauveria Bassiana, Neem, And A Tomato Inter-Crop On Diamondback Moth (Plutella Xylostella L.) (Lepidoptera: Plutellidae) In Tharaka-Nithi County, Kenya, Ceciliah N. Ngugi, Jesca N. Mbaka Mbaka, Hellen W. Muthengi Sep 2023

Effects Of Bacillus Thuringiensis, Beauveria Bassiana, Neem, And A Tomato Inter-Crop On Diamondback Moth (Plutella Xylostella L.) (Lepidoptera: Plutellidae) In Tharaka-Nithi County, Kenya, Ceciliah N. Ngugi, Jesca N. Mbaka Mbaka, Hellen W. Muthengi

Tanzania Journal of Science

Cabbage (Brassica oleracea var. capitata) is an important crop in Kenya, ranked 3rd among the exotic vegetables. Diamondback moth (DBM) is a major cabbage pest that can cause a 100% loss in yield if not well managed. Farmers indiscriminately use synthetic pesticides associated with environmental, health, and pest resistance concerns to manage the DBM. To increase the availability of technologies for effective management of DBM in Kenya, three biopesticides; BioPower (Beauveria bassiana 1.0 x 108 CFUs/g), Dipel DF® (Bacillus thuringiensis subsp. kurstaki), Neemraj Super 3000 (Azadirachtin 0.3% EC), and a tomato inter-crop were evaluated. Cabbages (30 plants) spaced at 40 …


An Overlapped Sub-Array Hybrid Beamforming Architecture With Successive Interference Cancellation And Water-Filling In Massive Mimo Systems, Godwin Mruma Gadiel Sep 2023

An Overlapped Sub-Array Hybrid Beamforming Architecture With Successive Interference Cancellation And Water-Filling In Massive Mimo Systems, Godwin Mruma Gadiel

Tanzania Journal of Science

Over the years, wireless communication has significantly improved the data rate of mobile users. The key drive behind this success is the technological advancement in wireless communication. In the physical layer, hybrid beamforming has revolutionized the way signal reaches the user by constructively adding the signal at the destination thus improving the performance. Many researchers works have proposed different algorithms to solve for optimal hybrid beamforming. However, there is no single algorithm that can achieve both high spectral efficiency and energy efficiency at the same time. This work proposes a hybrid algorithm that combines successive interference cancellation and water filling …


Optical Characterization Of Photocatalytic Tungsten Oxide/Tin Oxide (〖Wo〗_3/〖Sno〗_2) Thin Films For Use In Degradation Of Water Pollutants, Victor Isahi, Christopher Maghanga, Mghendi Mwamburi, Onesmus Munyati, Sylvester Hatwaambo, Emmanuel Akoto, Wycliffe Isoe, Mir Waqas Alam Sep 2023

Optical Characterization Of Photocatalytic Tungsten Oxide/Tin Oxide (〖Wo〗_3/〖Sno〗_2) Thin Films For Use In Degradation Of Water Pollutants, Victor Isahi, Christopher Maghanga, Mghendi Mwamburi, Onesmus Munyati, Sylvester Hatwaambo, Emmanuel Akoto, Wycliffe Isoe, Mir Waqas Alam

Tanzania Journal of Science

Organic pollutants in water have been a challenge and pose significant risks to human health. As a result, research efforts to eliminate these pollutants have been on the rise. Photocatalysis has shown incredible potential in water treatment containing organic pollutants since it is affordable and utilizes solar energy. Tin oxide ( ) has ardently been investigated as a photocatalyst for water treatment due to its remarkable properties such as; non-toxicity, and stability. However, its wide band gap and the tendency for some electrons and holes to recombine during its use have been cited to be among limiting factors affecting its …


Assessment Of The Offline Setup Correction Protocol And Thermoplastic Mask Use For Head And Neck Cancer Radiotherapy: A Single Institution Experience, Furahini Yoram, Nazima Dharsee, Khamza Maunda, Jumaa D. Kisukari, Geofrey F. Soko Sep 2023

Assessment Of The Offline Setup Correction Protocol And Thermoplastic Mask Use For Head And Neck Cancer Radiotherapy: A Single Institution Experience, Furahini Yoram, Nazima Dharsee, Khamza Maunda, Jumaa D. Kisukari, Geofrey F. Soko

Tanzania Journal of Science

This study assessed the efficiency of offline setup correction protocol and the use of a thermoplastic mask for head and neck cancer (HNC) patients treated with three-dimensional conformal radiotherapy at Ocean Road Cancer Institute. A prospective study was conducted from April to August 2021 to verify 62 patients’ treatment setup using an offline setup correction protocol while immobilized with a thermoplastic mask. Megavoltage images were matched with digitally reconstructed radiographs obtained during CT simulation to determine the gross set-up deviations. Box plots were used to show the deviations on three consecutive days of the first week and a successive weekly …


Effective Enhancement Of Post-Harvest Tomato Storage Through Wrapping Using Deacetylated Chitin Nanofibril-Plasticized Honey Films, Ngesa Ezekiel Mushi, Edina Meela, Divina Kaombe Sep 2023

Effective Enhancement Of Post-Harvest Tomato Storage Through Wrapping Using Deacetylated Chitin Nanofibril-Plasticized Honey Films, Ngesa Ezekiel Mushi, Edina Meela, Divina Kaombe

Tanzania Journal of Science

As one of the most grown seasonal fruit, tomato is widely consumed for making food products, drugs and ornaments. However, poor post-harvest handling system, transport and storage facilities deteriorate the quality of tomato fruits resulting into post-harvest losses. These problems have been addressed by the use of nanotechnology in this study. The combination of a chitosan surface and the core shell chitin results into novel deacetylated chitin nanofibril (DeChNF) with good biological activity and mechanical strength. The effectiveness of the DeChNF films for food preservation as an alternative material to chitosan is investigated. The DeChNF with degree of acetylation (DA) …


Hydro-Geochemistry And Related Processes Controlling The Composition Of Thermal Waters In The Lake Natron Basin, Northern Tanzania, Edista A. Abdallah, Charles H. Kasanzu, Crispin P. Kinabo, Akira Imai Sep 2023

Hydro-Geochemistry And Related Processes Controlling The Composition Of Thermal Waters In The Lake Natron Basin, Northern Tanzania, Edista A. Abdallah, Charles H. Kasanzu, Crispin P. Kinabo, Akira Imai

Tanzania Journal of Science

Lake Natron Basin (LNB) forms part of the eastern branch of the East African Rift System (EARS) in Tanzania. The basin is endowed with thermal springs flowing towards the lake from the western, northwestern, southwestern and eastern parts. The western, northwestern and south-western thermal springs emanate from fractures in the basaltic rocks while in the east, they originate from the western flank of the Gelai volcano. There are limited studies on these springs, thus their geochemical differences and distributions of physicochemical parameters are not well understood. A hydrogeochemical study was conducted to interpret available geochemical data from the LNB springs, …


Mineralogy And Geochemical Characteristics Of Matamba Kaolin Deposit-Njombe Region South-Western Tanzania: Implications For Industrial Applications, Melania A. Nyimbo, Ronald J. Massawe, Michael M. Msabi Sep 2023

Mineralogy And Geochemical Characteristics Of Matamba Kaolin Deposit-Njombe Region South-Western Tanzania: Implications For Industrial Applications, Melania A. Nyimbo, Ronald J. Massawe, Michael M. Msabi

Tanzania Journal of Science

Kaolin is a commercial clay material composed of hydrated aluminosilicate mineral kaolinite and used in various industrial applications such as ceramics, paper, paints, refractories, fiberglass, plastics, cosmetics and pharmaceuticals. It is formed as a result of strong chemical weathering of crystalline and feldspar-rich rocks or hydrothermal alteration of granitic rocks at relatively low temperature and pressure conditions. The kaolin deposit of Matamba originated from the weathering of leucogabbro rock during the development of the African land surface. In view of highlighted properties, the mineralogy and chemical characteristics of the Matamba kaolin deposit were investigated to determine its industrial applications. As …


Design Of A Cooling System Integrated With Ultraviolet Light For Preservation Of Fruits And Vegetables At Variable Tropical Weather Conditions: A Case Study Of Arusha, Tanzania, John Pyuza Gunda, Alexander Pogrebnoi, Baraka Kichonge Sep 2023

Design Of A Cooling System Integrated With Ultraviolet Light For Preservation Of Fruits And Vegetables At Variable Tropical Weather Conditions: A Case Study Of Arusha, Tanzania, John Pyuza Gunda, Alexander Pogrebnoi, Baraka Kichonge

Tanzania Journal of Science

Post-harvest losses of fruits and vegetables pose significant challenges, especially in tropical climates. This study introduces the development and performance evaluation of a solar-powered evaporative cooling storage system integrated with ultraviolet light (UV) designed for preservation of perishable fruits and vegetables. The cooling chamber supplied with ultraviolet lamp was developed using locally available materials such as sisal, sponge, and bricks. The performance of the system was evaluated in terms of air temperature decrease, relative humidity increase, and evaporative cooling power capacity both for sunny and cloudy tropical weather conditions. The study reveals that activating the UV light considerably extends the …


Wind Speed Forecasting Using Wavelet Analysis And Recurrent Artificial Neural Networks Based On Local Measurements In Singida Region, Tanzania, Rajabu J. Mangara, Mwingereza J. Kumwenda Sep 2023

Wind Speed Forecasting Using Wavelet Analysis And Recurrent Artificial Neural Networks Based On Local Measurements In Singida Region, Tanzania, Rajabu J. Mangara, Mwingereza J. Kumwenda

Tanzania Journal of Science

High accuracy wind speed forecasting is essential for wind energy harvest and plays a significant role in wind farm management and grid integration. Wind speed is intermittent in nature, which makes the forecasting to be a big challenge. In the present study, three hybrid single-step wind speed forecasting techniques are proposed and tested by local measurement data in Singida region, Tanzania. The three techniques are based on Wavelet Analysis (WA), Back Propagation (BP) optimization algorithm, and Recurrent Neural Network (RNN). They are referred to as WA-RNN, BP-RNN, and WA-BP-RNN. The model results showed that WA-BP-RNN outperforms the other two proposed …


Spirulina (Arthrospira Fusiformis, Gomont 1892) As A High-Quality Feed Ingredient For Nile Tilapia Fingerlings, Angelina Michael, Margareth S. Kyewalyanga, Charles V. Lugomela Sep 2023

Spirulina (Arthrospira Fusiformis, Gomont 1892) As A High-Quality Feed Ingredient For Nile Tilapia Fingerlings, Angelina Michael, Margareth S. Kyewalyanga, Charles V. Lugomela

Tanzania Journal of Science

A partially randomized experimental design was conducted to evaluate the effect and potential of spirulina species (Arthrospira fusiformis) isolated from Momela Lakes, Tanzania, on the growth, antioxidant capacity, feed utilization, and body composition of Nile tilapia fingerlings. Five dietary treatments were formulated, including spirulina meal at 5%, 10%, and 15% of the total diets, as well as control diets with freshwater shrimp or Lake Victoria sardine. The protein content of the experimental diets was 25, 28, and 35% for a treatment containing spirulina at 5, 10, and 15% inclusion, respectively, while the control diets had 35% crude protein each. After …


Microplastics In Marine Sediments From Dar Es Salaam Coast: Spatial Distribution And Characterization, Macarius P. Mtega, Matobola J. Mihale, Kessy F. Kilulya Sep 2023

Microplastics In Marine Sediments From Dar Es Salaam Coast: Spatial Distribution And Characterization, Macarius P. Mtega, Matobola J. Mihale, Kessy F. Kilulya

Tanzania Journal of Science

The purpose of the research was to determine the spatial distribution and characterization of microplastics in marine sediments of beaches along the Indian Ocean of Dar es Salaam coast. The sediment samples were extracted in triplicate using floatation method followed by digestion of organic debris, then analyzed using At-FTIR spectrophotometer and stereomicroscope. The mean concentrations of microplastics for Kijichi Beach were 700 ± 907 particles/m2 at 1 cm, 859 ± 839 particles/m2 at 5 cm and 590 ± 782 particles/m2 at 10 cm; from Palm Beach were 157 ± 15 particles/m2 at 1 cm, 130 ± 182 particles/m2 at 5 …


Experimental Measurements Of Ignition Delay Times Of Iso-Octane/N-Butanol Blend Mixtures In Rapid Compression Machine (Rcm), Myeji Materego, Derek Bradley Sep 2023

Experimental Measurements Of Ignition Delay Times Of Iso-Octane/N-Butanol Blend Mixtures In Rapid Compression Machine (Rcm), Myeji Materego, Derek Bradley

Tanzania Journal of Science

Among oxygenated alternative fuels, n-butanol is considered as a promising alternative biofuel which can partially (or fully) replace conventional transportation fuels currently in use. However, before n-butanol can be commercially utilised, its fundamental combustion characteristics need to be fully understood. In this work, the effect of adding n-butanol on autoignition property of iso-octane was studied. Measurements of ignition delay times for the two blends of n-butanol proportions of 30% and 50% by mole weight were made in a Rapid Compression Machine for stoichiometric mixtures at 2.0 MPa and temperature range 651-918 K. n-butanol increased ignition delay times of iso-octane at …


Ethnobotanical Survey On The Knowledge And Use Of Medicinal Plants For Malaria Management Among University Students, Felista W. Mwingira, Deokary J. Matiya, Neema G. Mogha Sep 2023

Ethnobotanical Survey On The Knowledge And Use Of Medicinal Plants For Malaria Management Among University Students, Felista W. Mwingira, Deokary J. Matiya, Neema G. Mogha

Tanzania Journal of Science

Malaria remains a public health problem in Tanzania, escalated by the emergence of both parasite and vector resistance. Plant-based traditional medicines have been widely utilized as alternatives to malaria management. However, proper documentation is minimal, especially among the younger generation. This study assessed the knowledge of medicinal plants for malaria management among 532 Dar es Salaam University College of Education students. Overall, twenty-four plant species, most belonging to the family Asteraceae, were identified with Azaradichta indica being the most dominant species. These results reveal a substantial knowledge of medicinal plants for malaria management among university students.


An Efficient Derivative Free Iterative Method And Condition Number Of Nonlinear Equations Arising From Real World Phenomena, Alatuhigha Nguni, Chacha S. Chacha, Adeline P. Mtunya Sep 2023

An Efficient Derivative Free Iterative Method And Condition Number Of Nonlinear Equations Arising From Real World Phenomena, Alatuhigha Nguni, Chacha S. Chacha, Adeline P. Mtunya

Tanzania Journal of Science

Recent researches have shown a great interest in developing novel numerical methods for solving nonlinear equations of the form  arising from real world phenomena.  However, very little attention has been given to the study of condition numbers which is an important aspect in measuring the sensitivity of the problem in response to slight perturbations in the input data. In this article, we present an efficient free derivative iterative scheme constructed by refining Newton-Raphson method standard form in which the derivative term is approximated by using finite difference scheme; hence making it derivative free. We also conducted an in-depth analysis of …


A Radial Basis Function Neural Network Algorithm For The Simultaneous Retrieval Of Two Meteorological Parameters From Solar Radiation, Nicholas W. Nzala, Nicolausi Ssebiyonga, Dennis Muyimbwa, Taddeo Ssenyonga Sep 2023

A Radial Basis Function Neural Network Algorithm For The Simultaneous Retrieval Of Two Meteorological Parameters From Solar Radiation, Nicholas W. Nzala, Nicolausi Ssebiyonga, Dennis Muyimbwa, Taddeo Ssenyonga

Tanzania Journal of Science

Local meteorological parameters are key in understanding the frequency of occurrence of extreme weather conditions such as floods, and droughts, among others. In this study, we present a method for simultaneous retrieval of two weather parameters. The method is based on already measured monthly average values of weather parameters from 2011 to 2016, which were used to train a Feed-forward radial basis function neural network (RBFNN) to obtain a fast and accurate method to compute global solar radiation for specified weather parameters pair. In inverse modelling, a multidimensional unconstrained non-linear optimization was employed to retrieve the weather parameters pair. The …


Evaluation Of The Inhibitive Properties Of Silver Nanoparticles In Senna Occidentalis Root Extract As Corrosion Inhibitor Of Mild Steel, Victor O. Egbeneje, Samuel E. Okhale, Chinyere Imoisi, Isaac O. Ogbogo, Omolade Ojo Sep 2023

Evaluation Of The Inhibitive Properties Of Silver Nanoparticles In Senna Occidentalis Root Extract As Corrosion Inhibitor Of Mild Steel, Victor O. Egbeneje, Samuel E. Okhale, Chinyere Imoisi, Isaac O. Ogbogo, Omolade Ojo

Tanzania Journal of Science

The use of nanoparticles as corrosion inhibitors has gained popularity because of its increased corrosion efficiency due to increase surface to volume ratio. Nanoparticles which undergo physisorption/chemisorption to the corrosion metal surface and inhibit the corrosion efficiently also have low toxicity, low cost and easy production. In this research work, weight lost method was applied to study the inhibitive properties of silver nanoparticles (AgNPs) synthesized using Senna occidentalis root extract as environmentally benign corrosion inhibitor of mild steel in 0.5 M H2SO4 medium at 298 K and 308 K. It was observed that the corrosion rate of the steel sample …


Enhancing Service Restoration In Tanzanian Power Grid Using Internet Of Things Sensors And Renewable Energy Sources, Rukia J. Mwifunyi, Daudi C. Mnyanghwalo, Shamte J. Kawambwa Sep 2023

Enhancing Service Restoration In Tanzanian Power Grid Using Internet Of Things Sensors And Renewable Energy Sources, Rukia J. Mwifunyi, Daudi C. Mnyanghwalo, Shamte J. Kawambwa

Tanzania Journal of Science

The increased dependence on the electric power grid, coupled with the increasing number of new customers, motivates the need to improve the reliability and resilience of the electric distribution systems. Modern distribution systems are becoming more resilient against power outages due to the increasing integration of Distributed Energy Resources (DERs) and the availability of efficient mechanisms for load shedding. Several studies considered fault detection and Service Restoration (SR) as separate problems without considering the implementation feasibility of integrating both solutions. To ensure the resiliency in the power system, it is important to have proper mechanisms which integrate sensing, detection, and …


Public Perceptions Of Water Quality In The Lake Bunyonyi Sub-Catchment, Western Uganda, Alex Saturday, Thomas J. Lyimo, Siajali Pamba, Susan Kangume, Jeniffer Turyatemba Sep 2023

Public Perceptions Of Water Quality In The Lake Bunyonyi Sub-Catchment, Western Uganda, Alex Saturday, Thomas J. Lyimo, Siajali Pamba, Susan Kangume, Jeniffer Turyatemba

Tanzania Journal of Science

Lake Bunyonyi ecosystem plays vital roles in water resource conservancy and tourism. Nevertheless, the rapid increase in human population and the unrelenting human activities are threatening the values, functions, and ecological integrity of the lake. In this study, the public perceptions of drinking water quality and its health implications in the Lake Bunyonyi Sub-catchment, Western Uganda are presented. A closed-ended questionnaire was administered to 267 respondents living within one Kilometre away from the lake shores. Besides, observation and interview methods were used to complement data collected by the questionnaire method. Results indicate that the prominent activities around the lake are …


The Realisation Of Grammatical Tone In Cigogo Verbs, Amani J. Chipalo Jul 2023

The Realisation Of Grammatical Tone In Cigogo Verbs, Amani J. Chipalo

Journal of Humanities and Social Sciences

This descriptive study aims to investigate how grammatical tone is realized in Cigogo verbs. The information was gathered through interviews and oral history techniques in the villages of Muungano, Ilolo, and Ndebwe in the Mvumi division. The replies from the interviews and the storytelling were captured using an MP3 recorder. The verb forms were then evoked for the analysis of the tone patterns based on the autosegmental theory. The findings show that Cigogo uses a grammatical tone to convey the perfective aspect, imperative mood, and reflexiveness in the past tense (immediate past). The kind of verb stem determines where the …


Language Contact And The State Of Multilingualism In The Linguistic Landscape Of Tete Province In Mozambique, Crisófia Langa Da Da Câmara, Amani Lusekelo Jul 2023

Language Contact And The State Of Multilingualism In The Linguistic Landscape Of Tete Province In Mozambique, Crisófia Langa Da Da Câmara, Amani Lusekelo

Journal of Humanities and Social Sciences

Mozambique is a multilingual country that adopted Portuguese as the language of official communication right from Independence Day in 1975. Later in the 1990s it adopted 19 Bantu languages as the media of instruction in lower education. This move opened an avenue for Bantu languages to be used in public domains in the country. Since the Metropolitan Maputo had been the centre of previous research of languages of public spaces, this paper looks at the language uses that unfold in the signposts of Tete Province to determine the manifestations of the Bantu languages in urban public spaces. Firstly, the findings …


Situational Analysis Of Gold Processing Practices At Artisanal And Small-Scale Gold Mining In Tanzania, Sospeter Maganga Jul 2023

Situational Analysis Of Gold Processing Practices At Artisanal And Small-Scale Gold Mining In Tanzania, Sospeter Maganga

Tanzania Journal of Engineering and Technology (TJET)

This study reports the state-of-art situation of gold processing practices at artisanal and small-scale gold mining (ASGM) in Tanzania. It involved literature review, document review of public domain reports, and field survey during data collection. This was followed by screening of literature, reports, and field data relevant to the study topic. Further, the strengths, weaknesses, opportunities, and challenges (SWOC) analysis of ASGM was conducted and discussed. The study indicates that ASGM subsector in Tanzania continues growing with people involved directly in ASGM ranging between 1 to 1.5 million. Further, the study indicates that ASGM in Tanzania contributes about 90% of …


On The Use Of Wireless Technologies For Wildlife Monitoring: Wireless Sensor Network Routing Protocols, Lilian Mutalemwa Jun 2023

On The Use Of Wireless Technologies For Wildlife Monitoring: Wireless Sensor Network Routing Protocols, Lilian Mutalemwa

Tanzania Journal of Engineering and Technology (TJET)

Traditional methods for wildlife monitoring are labor-intensive and time-consuming. Therefore, advanced technologies and remote monitoring methods are becoming increasingly popular. This paper presents a study on wireless technologies for wildlife monitoring. In the study, a review of the literature was done to identify the most commonly used wireless technologies. Various technologies were explored including unmanned aerial vehicles (UAVs), Internet of Things (IoT), wireless sensor networks (WSNs), artificial intelligence (AI), global positioning system (GPS), and very high frequency (VHF) radio. Then, a more detailed study was done on WSN technology. Investigations were done to observe the performance of routing protocols in …


Determination Of Cyanide Concentration Levels In Surface Water And Soil From Artisanal Small-Scale Gold Mining Villages At Chunya, Mbeya - Tanzania, Mahir Mohammed Said Jun 2023

Determination Of Cyanide Concentration Levels In Surface Water And Soil From Artisanal Small-Scale Gold Mining Villages At Chunya, Mbeya - Tanzania, Mahir Mohammed Said

Tanzania Journal of Engineering and Technology (TJET)

This study aimed to determine levels of cyanide (CN) pollution in the soil and surface water at selected mining sites of Mbeya region. A total of (n = 124) samples were collected and analyzed by spectrophotometry. The cyanide levels of soil-based samples and water-based samples at Mwasenga, and Ifumbo mining sites were above the permissible limits. This was due to poor disposal of tailing from the gold processing plants and mismanagement of wastewater. On the other hand, the Cyanide was within the allowable limit for both soil and water at Godima, Itewe, Ashishira and Nyatula mining sites. This was attributed …


Assessment Of Spatial Variability Of Groundwater Levels In Moroto District, Uganda, Augustina Clara Alexander Dr Jun 2023

Assessment Of Spatial Variability Of Groundwater Levels In Moroto District, Uganda, Augustina Clara Alexander Dr

Tanzania Journal of Engineering and Technology (TJET)

Globally, the variation of groundwater levels is increasingly overwhelming due to over exploitation resulting from population growth. The dynamic nature of socio-economic activities in Moroto District such as agriculture, settlements and increased trends in irrigation technology has been well-known worldwide as common parameters triggering groundwater variability. Nevertheless, determination of groundwater levels for groundwater management and development purpose is a challenge due to spatial variability in levels across Moroto District. In this study, geostatistical technique in Geographical Information System (GIS) was used to analyze spatial variability of water levels in the study area. The analysis utilized ordinary Kriging method to predict …


Performance Evaluation Of Full Array, Sub-Array And Overlapped Sub-Array Hybrid Beamforming Architectures For Massive Mimo Systems, Godwin Mruma Gadiel Jun 2023

Performance Evaluation Of Full Array, Sub-Array And Overlapped Sub-Array Hybrid Beamforming Architectures For Massive Mimo Systems, Godwin Mruma Gadiel

Tanzania Journal of Engineering and Technology (TJET)

The technological advancement in wireless communication, promises high data rate for end users. This has led to the possibility of smart cities, inter connected vehicles, and virtual reality applications. One of the recent technologies in wireless communication is massive MIMO where large number of antennas are deployed at the transmitter or receiver. This is possible due to the use of mmWave in wireless communication. With massive MIMO, beamforming technique can be employed in the communication system. Beamforming is the ability of communication system to direct power to the intended users and to cancel power at non-intended users and thus significantly …


Product Costing And Pricing In Small And Medium Enterprises In Tanzania, Cosmas F Kindole Jun 2023

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 …


Experimental Investigation On Recovery Of Micro Hydropower Dump Load Through Oil Heating System, Joseph H. Kihedu Dr. Jun 2023

Experimental Investigation On Recovery Of Micro Hydropower Dump Load Through Oil Heating System, Joseph H. Kihedu Dr.

Tanzania Journal of Engineering and Technology (TJET)

Micro hydropower power generates electrical energy to meet connected electrical demand, that normally fluctuates causing imbalances. Electronic load controller is then used to balance power system by diverting surplus generated power to the dump load commonly resistive load such as bulk water heater. This study investigated use of oil heating system as a replacement for conventional resistive dump load. In comparison to water, oil has high thermal retention therefore can serve as good thermal media. Dump load range ranged between 17 kW to 78 kW. A 6-kW electrical heater was used for laboratory oil heating system from which heated oil …


Assessments Of The Application Of Earned Value Management System For Construction Project Performance Measurement In Zanzibar, Juma M. Matindana Jun 2023

Assessments Of The Application Of Earned Value Management System For Construction Project Performance Measurement In Zanzibar, Juma M. Matindana

Tanzania Journal of Engineering and Technology (TJET)

Many construction projects in developing countries including in Zanzibar suffer from time and budget overruns. The Revolution Government of Zanzibar established different bodies such as Zanzibar Contractors Registration Board (ZCRB), Zanzibar Architects, Engineers and Quantity Surveyors Registration Board (ZAEQRB), Zanzibar Public Procurement and Disposal of Public Asset Authority (ZPPDA), among others with the aim of controlling the performance of project. Often scope creep, time and cost overruns are very common problems in construction projects. This study aims at addressing those problems by assessing the use of Earned Value Management (EVM) methodology in measuring construction industry performance in Zanzibar. The study …