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Tanzania Journal of Engineering and Technology (TJET)

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Full-Text Articles in Engineering

Reliability Improvement In The Traction System Of Tanzania Standard Gauge Railway, Yusufu Katuga Feb 2024

Reliability Improvement In The Traction System Of Tanzania Standard Gauge Railway, Yusufu Katuga

Tanzania Journal of Engineering and Technology (TJET)

In recent years, many African governments have been developing Standard Gauge Railway (SGR) to replace the old after becoming absolute, inefficient Meter Gauge System (MGR) to carry more loads at high mileage and speed while combating the oil and environmental crises. With the increase of SGR, the amount of traction systems has grown sharply, the service life of the traction system has increased gradually, and the components of the vehicle traction system have become worn and aged as a result. While Tanzania is transitioning to SGR with its gradually increasing traction systems, reliability improvement becomes a key for the sustainability …


A Two-Stage Based Life Cycle And Principal Component Analysis For Decision Support Of Potential Municipal Solid Wastes Management Scenarios, Case Study Dar Es Salaam, Tanzania, Edwin Richard Ndibalema Dr Feb 2024

A Two-Stage Based Life Cycle And Principal Component Analysis For Decision Support Of Potential Municipal Solid Wastes Management Scenarios, Case Study Dar Es Salaam, Tanzania, Edwin Richard Ndibalema Dr

Tanzania Journal of Engineering and Technology (TJET)

In most of the urban areas of Tanzania, poor and inadequate solid waste management is a growing environmental and public health concern. Despite an array of solid waste management options, choosing an appropriate one remains a challenge. This study applied a novel two-stage-based approach to assess the environmental impacts and sustainability performance of the 27 scenarios for municipal solid wastes (MSW) management of Dar es Salaam City, Tanzania. In the first stage, the study utilized a life cycle analysis (LCA) to quantify the environmental impacts of MSW scenarios. In the second stage, the study used the principal component analysis (PCA) …


Cost Estimation Proxy Models For Economic Evaluations In Petroleum Projects: A Case Study From The Onshore Gas Field In The Southern Coastal Tanzania Basin, Fulmence Kaborogo Feb 2024

Cost Estimation Proxy Models For Economic Evaluations In Petroleum Projects: A Case Study From The Onshore Gas Field In The Southern Coastal Tanzania Basin, Fulmence Kaborogo

Tanzania Journal of Engineering and Technology (TJET)

Petroleum economic evaluation involves estimating revenues from forecasted production profiles and field costs including capital expenditures (CAPEX), drilling expenses (DRILLEX), and operating expenses (OPEX). The existing cost-estimating tool requires several inputs making it time-intensive and difficult to use with few data during the early stages of projects. Majority of the previously developed time saving cost estimations proxy models rely on unrealistic assumptions that include uniform operational costs for different fields with a different number of wells, casings, and drilled depths. This work focused at developing proxy models that consider the variability of the development costs with different parameters. The developed …


Employment Of Intelligent Predictive Maintenance On Thermal Power Plant Component Parts Taking Condenser Vacuum As A Case Study, Titus Ajewole Nov 2023

Employment Of Intelligent Predictive Maintenance On Thermal Power Plant Component Parts Taking Condenser Vacuum As A Case Study, Titus Ajewole

Tanzania Journal of Engineering and Technology (TJET)

This work proposes deployment of machine learning in the maintenance of individual constituent parts of steam power plant assemblages. With the condenser vacuum of a steam turbine (in a six-turbine plant assemblage) taken as a case study, information on the past operating parameters of the selected plant component was used to forecast its future working condition. Based on Exponential Gaussian Process of Regression, a model was developed, trained using the diachronic operational data, and employed in determining the future. A quantitative evaluation was employed to provide the distribution of the test values of the data about the lines of regression, …


Hydrological System And Water Balance Of Ungauged Crater Lakes Of The Northern Crater Highlands, Godwin Lucas Nov 2023

Hydrological System And Water Balance Of Ungauged Crater Lakes Of The Northern Crater Highlands, Godwin Lucas

Tanzania Journal of Engineering and Technology (TJET)

The study aimed to unveil the hydrological system and water balance of the ungauged crater lakes with major focus on the Emakati Lake which occupy 46% of the Empakaai Crater associated to the East African Rift Valley and form part of the Northern Crater Highlands. Water samples for analysis of NO3- , Cl- and stable isotopes (2H and 18O) were collected from the Emakat lake, springs of the inner, outer and the foot of the Empakaai Crater rims. A combination of satellite data such as digital elevation model (DEM), Climate Hazards Group Infrared Precipitation with Station data (CHIRPS), net shortwave …


Aquaculture In Hydropower Reservoirs, Racheal Macharia Sep 2023

Aquaculture In Hydropower Reservoirs, Racheal Macharia

Tanzania Journal of Engineering and Technology (TJET)

There is an undoubtedly existing relationship between water, energy, and food and their interaction with the natural environment and mankind. Climate change is the talk of the day in global development discussions as it intensifies water shortages, energy, poverty, food shortages, and environmental degradation. Currently, most of the hydropower dams constructed in Africa are majorly built to store water for agricultural purposes, control flooding, and generate electricity. Notable projects include the seven forks hydropower stations located on the Tana River in Kenya; Aswan high dam in Egypt; Grand Renaissance dam in Ethiopia; Kariba dam in Zimbabwe and Akosombo in Ghana. …


Mppt Dc-Dc Buck-Boost Converter For Off Grid Hybrid Solar-Wind Battery System In Ikuza Island, Tanzania, Aviti Thadei Mushi Sep 2023

Mppt Dc-Dc Buck-Boost Converter For Off Grid Hybrid Solar-Wind Battery System In Ikuza Island, Tanzania, Aviti Thadei Mushi

Tanzania Journal of Engineering and Technology (TJET)

Ikuza Island in Kagera-Tanzania faces lack of electricity due to cost challenges of extending the grid by marine cables and other transmission facilities. These makes such endeavour not appealing to the supply authority due to those higher charges. Therefore, this paper undertakes to design hybrid renewable energy sources for the island by specifically focusing on the buck-boost converter for the energy conversion from these renewable resources. The design of the bidirectional buck-boost converter for maximum power point tracking in off-grid hybrid renewable energy systems is multifaceted due to the inhomogeneity nature of the renewable energy sources. The bidirectional buck-boost converter, …


Designing A Cylindrical Capacitive Based Sensor For Monitoring The Table Salt’S Moisture Content During Iodization, Mwajuma Lungo Sep 2023

Designing A Cylindrical Capacitive Based Sensor For Monitoring The Table Salt’S Moisture Content During Iodization, Mwajuma Lungo

Tanzania Journal of Engineering and Technology (TJET)

Coaxial cylinder capacitive moisture sensor for determination of moisture content of table salts has been fabricated. The CMS method for determination of moisture content of table salts overcomes the effect of evaporation of iodine in table salt which results from heating in the oven drying method. The CMS overcomes the polarization effect result from the resistive methods of moisture content determination and it is non expensive to construct and it has high accuracy since measurements involves programming system in interpretation of the results. In this research, moisture content sensor based on capacitive principal created using two coaxial cylinders with height …


Assessing Spatio-Temporal Variations And Trends Of Rainfall Over Somalia From 1991 To 2020, Paul Ts Limbu Sr Sep 2023

Assessing Spatio-Temporal Variations And Trends Of Rainfall Over Somalia From 1991 To 2020, Paul Ts Limbu Sr

Tanzania Journal of Engineering and Technology (TJET)

This study aims to examine the spatiotemporal variability and trends of rainfall over Somalia using the Mann-Kendall (MK) test and Sen’s slope estimator to investigate the trend and magnitude of the rainfall changes and the arithmetic mean and coefficient of variation (CV) to examine the rainfall variability. To achieve this aim, the gridded monthly satellite rainfall datasets from Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) for the period between 1991 and 2020 were used. Results show that annual rainfall generally exhibits bimodal rainfall distribution, March to May (Gu) and September to November (Deyr), though southern coastal regions receive extended …


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 …


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 …


A Perspective Into Development Of Pavement Design Methods For Low Volume Roads: A Review, Mwajuma Lingwanda Jun 2023

A Perspective Into Development Of Pavement Design Methods For Low Volume Roads: A Review, Mwajuma Lingwanda

Tanzania Journal of Engineering and Technology (TJET)

The definition of low volume roads (LVRs) is not time static and it varies from place to place around the world. The importance of such roads for providing access, in connecting communities and link farms to markets is well appreciated worldwide. LVRs are credited as the direct source of social economic development in rural communities, growth, reduction of poverty and sustaining livelihood. Nevertheless, the LVR network is growing at an unsatisfactory rate especially in Sub-Saharan Africa. The slow rate in developing LVR network is attributed to the high cost of construction and maintenance. To the author’s perspective, research has a …


Towards Lean Manufacturing In Developing Countries: Research Gaps And Directions In Tanzania, Francis D. Sinkamba Feb 2023

Towards Lean Manufacturing In Developing Countries: Research Gaps And Directions In Tanzania, Francis D. Sinkamba

Tanzania Journal of Engineering and Technology (TJET)

In the current knowledge-driven economy, many industries across the globe are forced to adopt manufacturing technologies such as lean manufacturing to remain competitive in the globalized world. Despite the increase in lean manufacturing implementations, the adoption rate in Tanzania is very low and estimated to be 8 percent. Likewise, the sustainability of lean manufacturing tools and practices is still questionable, which shows the need to develop lean maturity models. To date, several lean maturity models have been developed but there is ARTICLE INFO Submitted: July 5, 2022 Revised: Sept. 28, 2022 Presented: Oct. 20, 2022 a lack of maturity models …


Design Of International Airport Hybrid Renewable Energy System, Aviti Thadei Mushi Feb 2023

Design Of International Airport Hybrid Renewable Energy System, Aviti Thadei Mushi

Tanzania Journal of Engineering and Technology (TJET)

This paper presents the design and simulation of a hybrid renewable energy system utilizing solar and wind energy sources with a backup generator. The demand for reliable electric energy in support of investments in large social and economic development activities such as airport operations has been an agenda worldwide. In Tanzania, Mwanza International Airport (MIA) expects to consume about 18 MVA of electric power annually to support its operations for the next 25 years. About 78-80% of the world's commercial energy comes from fossil fuels. Non-renewable fuels and other negative effects contribute to global warming through greenhouse gas emissions and …


Sensible Heat Bean Cooker, Casiana Lwiwa Feb 2023

Sensible Heat Bean Cooker, Casiana Lwiwa

Tanzania Journal of Engineering and Technology (TJET)

Alternative cooking energy to replace wood fuels is needed in the African context. Liquified Natural Gas (LNG) is a solution but is still based on burning fossil fuel. Electrical cookers can be an alternative as well. However, for off-grid systems this means electrical batteries are required, as the solar electricity from Photovoltaic (PV) panels is intermittent, and as cooking is also to be made after sunset. Heat storage technologies can provide solutions where available energy is stored in the form of heat for cooking when needed. The challenge is then to develop systems which are robust, safe, and technically simple. …


Development Of Solar Pv Systems For Mini-Grid Applications In Tanzania, Seleman Mayanjo Feb 2023

Development Of Solar Pv Systems For Mini-Grid Applications In Tanzania, Seleman Mayanjo

Tanzania Journal of Engineering and Technology (TJET)

Access to electricity offers great benefits to development through the provision of reliable and efficient energy sources in the country. Majority of the population living in the remote and rural areas of developing countries mostly sub-Saharan Africa are not supplied with electricity. Although the governments through their electricity companies put their effort to extends the grid distribution networks to remote and rural areas still the coverage were not sufficiently enough due to growing demands for safe and reliable electricity. However, solar as a source of energy remains the least utilized energy source in many countries including Tanzania. Solar Photovoltaic (PV) …


Current And Future Trends Of Construction Project Performance Models: A Review, Method Mtana Feb 2023

Current And Future Trends Of Construction Project Performance Models: A Review, Method Mtana

Tanzania Journal of Engineering and Technology (TJET)

The construction industry (CI) has experienced outstanding growth and contributed to economic growth for many countries, with enormous foreign investments that require quality projects. High pressure to reduce the construction cost and time commonly put the industry at risk of lower quality and safety of the construction facilities. Like many other developing countries, Tanzania needs more stringent quality control measures in the construction sector to contribute positively to sustainable growth. This study thus reviews current and future trends in construction industry performance in Tanzania. The literature review on construction projects (CPs) performance is based on information on time overruns from …


Towards The Development Of A Framework For Assessing Organizational Governance Maturity For Technical Audit Of Public Works, George Haule Feb 2023

Towards The Development Of A Framework For Assessing Organizational Governance Maturity For Technical Audit Of Public Works, George Haule

Tanzania Journal of Engineering and Technology (TJET)

The quality of the audit work and its products is often associated with the organizational maturity of the audit function. The absence of a well-defined organizational maturity for an audit function leads to poor quality of audit work or products and ineffective audit function. The lack of a framework for measuring governance maturity was identified as a major deterrent factor to the attainment of quality audit work. Measuring the governance maturity of the technical audit of public works is challenging due to the absence of a maturity framework that fits its needs. The noted shortcomings include: (a) existing maturity frameworks …


Lead Acid Battery Recycling In The Current Tanzania Industrialization Drive: Challenges And Opportunities, Divina D. Kaombe Dec 2022

Lead Acid Battery Recycling In The Current Tanzania Industrialization Drive: Challenges And Opportunities, Divina D. Kaombe

Tanzania Journal of Engineering and Technology (TJET)

ABSTRACT Advancements in automotive technologies, Information and Communications Technology and renewable energy technologies have increased the use of lead acid batteries as a source of portable and rechargeable energy. This has considerably increased the number of spent batteries with adverse effects on the environment and human health; which calls for recycling of spent batteries. This work was conducted to investigate challenges facing the formal business of recycling spent batteries and potential manufacturers of new lead-acid batteries in Tanzania. The work involved collection of information from key stakeholders such as collectors, dealers, Tanzania Revenue Authority and recyclers. It was found out …


Characteristics Of Extreme Precipitation And Their Effect On Bean Yield In Rwanda, Paul Ts Limbu Sr Dec 2022

Characteristics Of Extreme Precipitation And Their Effect On Bean Yield In Rwanda, Paul Ts Limbu Sr

Tanzania Journal of Engineering and Technology (TJET)

This study examines the characteristics of extreme precipitation and its effect on bean yield in Rwanda from 1981 to 2017. Over the study area, two rainy seasons, March to May (MAM) and September to December (SOND), account for approximately 80% of total rainfall. The spatial distribution of rainfall over Rwanda revealed that the first three EOF modes of MAM rainfall vary by 72.72 percent over the study period, while the first three EOF modes of SOND rainfall vary by 57.48 percent. The spatial analysis of extreme precipitation reveals that during wet years, the majority of the country's western regions receive …


A Chemical Study Of Archaeometallurgical Ceramics From Southwestern Tanzania, Edwinus Lyaya Dec 2022

A Chemical Study Of Archaeometallurgical Ceramics From Southwestern Tanzania, Edwinus Lyaya

Tanzania Journal of Engineering and Technology (TJET)

Archaeometallurgical ceramics, including furnaces, tuyères, and potteries, were required for successful pre-industrial iron smelting and refining. However, there are limited chemical studies on archaeometallurgical ceramics in Tanzania. This paper examined the nature of clay source in terms of refractoriness, determined whether there were multiple clay sources, and verified the refractoriness of the archaeometallurgical ceramics. An x-ray fluorescence (XRF) analytical technique and experimental re-firing of the archaeometallurgical ceramics were employed. The chemical data clustered in the mullite region on the Al2O3-SiO2-FeO ternary system indicate that iron smelters and refiners chose refractory clay sources for making archaeometallurgical ceramics. Small range and standard …


Properties Of (Cd, Zn)S Films Deposited By Dc Co-Sputtering, Lwitiko P. Mwakyusa Dec 2022

Properties Of (Cd, Zn)S Films Deposited By Dc Co-Sputtering, Lwitiko P. Mwakyusa

Tanzania Journal of Engineering and Technology (TJET)

CdS thin film is commonly used as a buffer layer in most thin film solar cells. However, the buffer layer with less absorption in the visible region of the solar spectrum as well as that which provides perfect lattice matching with the absorbers is required. The incorporation of Zn in the CdS films can affect the structural and optical properties of the buffer layer. In this work, films of CdS and (Cd,Zn)S films were deposited by DC sputtering utilizing CdS and Zn targets. The concentration of Zn in the CdS was varied by changing the sputtering power of the Zn …


Assessing Morphological Changes Of The Msimbazi River Using Satellite Images, Fides J. Izdori Dec 2022

Assessing Morphological Changes Of The Msimbazi River Using Satellite Images, Fides J. Izdori

Tanzania Journal of Engineering and Technology (TJET)

This study assessed historical morphology changes of the Msimbazi River in Dar es Salaam City, Tanzania, following heavy rainfall events using historical Google earth images. The erosion and sedimentation processes that cause morphological changes of a river are also associated with flooding within the river catchments. In this study, the bank-line movement, erosion and sedimentation areas and changes in river section width were analyzed under three-time periods: 2005- 2012, 2012- 2018, and 2018- 2020. Data shows that, the timing for floods coincides with the historical records for heavy rains. It was found that, area in the upper reaches of the …


Concrete Technology In A Rapidly Growing Urban Environment – The Case Of Dar Es Salaam City, John K. Makunza Jkm Dec 2022

Concrete Technology In A Rapidly Growing Urban Environment – The Case Of Dar Es Salaam City, John K. Makunza Jkm

Tanzania Journal of Engineering and Technology (TJET)

Concrete is a building material that is used in great quantities second only to our use of water. The ingredient materials of concrete include cement, fine and coarse aggregates plus a reasonable amount of water, and sometimes additives. The construction of various structures like, residential buildings, commercial buildings, hospitals, schools, bridges, etc., needs good quality concrete. Good modern technologies are needed by the construction industry in order to effectively construct buildings which are durable. A study has been done with the main objective of assessing the concrete technologies existing in rapid growing cities in Sub-Sahara Africa like Dar es Salaam, …


Development Of An Operational Satellite-Based Flood Monitoring Model For Tanzania, Andrew Kimati Dec 2022

Development Of An Operational Satellite-Based Flood Monitoring Model For Tanzania, Andrew Kimati

Tanzania Journal of Engineering and Technology (TJET)

Timely information during water related disasters is of utmost importance for flood preparedness and risk reduction. However, the conventional ground-based photographic monitoring of flooded areas is an expensive and time-consuming exercise. Satellite remote sensing is a quick and affordable approach that can be used for concurrent floods detection at different scales. This is important as it facilitates timely information for emergency response to disaster management departments, even in scarcely instrumented catchments. This study presents a novel approach for flood tracking using satellite image remote sensing science to map flood affected areas immediately after occurrence of rainfall events. An open-source water …


Analysis Of Ore Hand-Crushed Size Distribution For Grinding Process In The Artisanal And Small-Scale Gold Mines Production: A Case Study Of Nholi Mine, Bahi District, Malugu Tembo Dec 2022

Analysis Of Ore Hand-Crushed Size Distribution For Grinding Process In The Artisanal And Small-Scale Gold Mines Production: A Case Study Of Nholi Mine, Bahi District, Malugu Tembo

Tanzania Journal of Engineering and Technology (TJET)

(ASGM) employed numbers of people compared to large-scale mines. The ASGM has been played a crucial role in poverty alleviation and rural development, particularly in developing countries. The mined ore is crushed and ground for beneficiation of gold. The grinding process involved the size reduction of blasted materials to acquire minerals of interest. This paper presents the size distribution of hand-crushed for blasted materials using sieve analysis and digital image processing. The sieve test results for hand-crushed blasted material of three muck-piles were ranged between 17 mm and 36 mm that is equivalent to 20% and 80% passings respectively, with …


Performance Evaluation Of Udsm Network To Deliver Multimedia Elearning Contents: Case Of Coict, Mercy Mbise Dec 2022

Performance Evaluation Of Udsm Network To Deliver Multimedia Elearning Contents: Case Of Coict, Mercy Mbise

Tanzania Journal of Engineering and Technology (TJET)

The use of technology in education in Sub-Saharan Africa has been reported to be hindered by many factors including inadequate Information and Communication Technology (ICT) infrastructure, low internet speed, and lack of skills to use educational technologies. This paper aim at evaluating how the available ICT infrastructure at the College of Information and Communication Technologies (CoICT) can support, with acceptable Quality of Service (QoS), the delivery of multimedia applications for eLearning services. The evaluation was performed over a network testbed implemented in a computer laboratory for wired and wireless connections. The testbed consisted of five personal computers (PCs) connected via …


A Robust Random Forest Prediction Model For Mother-To-Child Hiv Transmission Based On Individual Medical History, Rebecca Chaula Dec 2022

A Robust Random Forest Prediction Model For Mother-To-Child Hiv Transmission Based On Individual Medical History, Rebecca Chaula

Tanzania Journal of Engineering and Technology (TJET)

Human Immunodeficiency Virus (HIV) continues to be a leading cause of mortality and reduces manpower throughout the world. HIV transmission from mother to child is still a global challenge in health research. According to UNAIDS, in every 7 girls, 6 are found to be newly infected among adolescents whereby 15-24 years are likely to be living with HIV which is the maternal age and likely to transfer to the child. Machine learning methods have been used to predict HIV/AIDS transmission from mother to child but left behind some important considerations including the use of patient-level information and techniques in balancing …


The Use Of Online Social Media Platforms By Tanzania Journalists To Produce And Disseminate Development News, Elisha Magolanga Dec 2022

The Use Of Online Social Media Platforms By Tanzania Journalists To Produce And Disseminate Development News, Elisha Magolanga

Tanzania Journal of Engineering and Technology (TJET)

Advancement in Information and Communication Technologies (ICT) are revolutionizing Development Journalism (DJ) into an effective strategy for building competitive economies globally. However, many countries in Africa including Tanzania are slow in tapping potentials of ICT for development journalism. Digital penetration in the form of the Internet and social media are changing the way in which journalists are mobilizing and engaging communities in journalism practises, a key strategy for a competitive digitalised economy. This paper was guided by Development Communication Theory and Diffusion of Innovation Theory to explore the use of online social media by journalists in Tanzania to practice development …