Digital Commons Network^™

Cyber Security Challenges, Its Emerging Trends On Latest Information And Communication Technology And Cyber Crime In Mobile Money Transaction Services, Hakeem J. Pallangyo

Tanzania Journal of Engineering and Technology (TJET)

This paper investigates the challenges emerging trends on latest Information and Communication Technology and cybercrime in mobile money transaction services in Tanzania. The objective of this is to evaluate the challenges associated with this rapid growth in ICT and to determine factors influencing Cybersecurity readiness and Cybercrimes in mobile money transaction services. Cyber Security plays a significant role in the field of Information and Communication Technology especially on mobile money transaction services. The study recognizes the provision of mobile money services by both telecommunication companies and local banks, the fact is that whenever we think about the cyber security, the …

Exploring Carrier Sense Multiple Access With Collision Avoidance Techniques For Resource Sharing In Broadband Power Line Communications, Godfrey Luwemba, Mussa M. Kissaka, Prosper Mafole

Tanzania Journal of Science

A resource sharing in power line communications (PLC) for the home network is restricted by the channel assignment techniques which decide who has the right to gain access to send data. The channel assignment techniques include contention-free and contention-based. The former requires high synchronization due to the deterministic round-trip time. Besides, contention-based utilizes CSMA/CA techniques that allow stations in a network to compete for channel access and are suitable for decentralized network topology. However, a trade-off exists between the number of stations required to gain access versus system efficiency. Whilst some research has been carried out on CSMA/CA resource sharing …

Carbon Monoxide Oxidation On Model Planar Titania Supported Platinum Nanoparticles Catalyst, Jovine Emmanuel, Brian Hayden

Tanzania Journal of Science

A high-throughput (parallel) thermographic screening methodology was developed to enable the measurements of the particle size and support influence on heterogeneous catalysts. A high throughput screening chip has been used to establish the catalytic activity of titania supported platinum nanoparticles catalyst for CO oxidation reaction. The catalytic activity of Pt nanoparticles between 1.3 to 7.8 nm has been investigated for CO conversion at a pressure of 0.11 and 1.1 mbar with O2:CO ratio of 1:1 at 80 °C and 0.6, 1.1 and 2.4 mbar at O2:CO ratio of 1:1 at 240 °C. At these experimental conditions, there was an increase …

Effects Of Annealing Ambient On The Structural, Optical And Electrical Properties Of Tio2:Ge Thin Films, Lilian A. Owino, Sebastian Waita, Robinson J. Musembi, Francis W Nyongesa

Tanzania Journal of Science

TiO2, a semiconducting material with a wide energy band gap, has been researched intensively due to its interesting properties and many potential applications. The films properties can as well be modified by preparing the films under diverse ambient to suit diverse applications. In this work, the effects of the annealing atmosphere on the structural, optical and electrical properties of pure TiO2 and TiO2:Ge composite thin films deposited by sputtering from commercially available pure TiO2 and TiO2:Ge (85:15) targets respectively were studied. The films were deposited on fluorine doped tin oxide glass substrates by radio frequency magnetron sputtering technique at room …

Cesspits As Onsite Sanitation Facilities In The Non-Sewered Palestinian Rural Areas: Users’ Satisfaction, Needs And Perception., Rehab Thaher, Nidal Mahmoud, Issam A. Al-Khatib, Yung-Tse Hung

Civil and Environmental Engineering Faculty Publications

The main aim of this research was to assess the problems of using cesspits in the non-sewered areas in the West Bank of Palestine by the means of a questionnaire, with a sample size of 485 households, targeting the cesspits’ owners. People who use cesspits for house onsite wastewater management are not satisfied with them, and most of them complain about high disturbance during discharge of the cesspits (75.5%). Emptying cesspits represents a financial burden, costing 6% of the households’ monthly income. The frequency of cesspits’ emptying decreases substantially when there are onsite GWTPs. People accept that constructing a house …

Resilient Modulus Of Siliciclastic Unbound Granular Materials Under Repeated Wheel Loading, Siya Rimoyi

Tanzania Journal of Engineering and Technology (TJET)

The Resilient Modulus (Mr) is a fundamental material property input in modern Mechanistic-Empirical (M-E) pavements structural design. Empirical pavement design methods have been in use over a long period during which large databases of four- days-soaked California Bearing Ratio (CBR) values at or near the Maximum Dry Density have been generated in the strength assessments for Unbound Granular Materials (UGMs). In the adoption of the M-E design approach researchers have so far attempted with various degrees of success to develop models to derive resilient modulus from the conventional CBR-based databases. This study provides an extensive laboratory experimental study to investigate …

Spatial And Temporal Variation Of Selected Water Quality Parameters In The Tanzanian Side Of Lake Victoria, Richard Joseph Kimwaga

Tanzania Journal of Engineering and Technology (TJET)

Lake Victoria’s water quality is increasingly becoming under heavy pressure mainly due to land based activities and aerial inputs which are taking place within the basin. This study was carried out to assess the spatial, including vertical and temporal, variation of the water quality of Lake Victoria on the Tanzanian side. Historical water quality data for the period from 2000 to 2016 was collected. Temperature, pH, Dissolved Oxygen (DO) and Turbidity were selected for study since they are the mostly measured and monitored water quality parameters. Land use-land cover changes were analysed using ArcGIS. ILWIS 3.7 software was used to …

Development Of Intensity-Duration-Frequency (Idf) Models For Manually Operated Rain Gauge Catchment: A Case Study Of Port Harcourt Metropolis Using 50 Years Rainfall Data, Francis Ogbozige

Tanzania Journal of Engineering and Technology (TJET)

Hydraulic structures such as surface drainages and culverts are usually constructed in urban areas with the intention of draining runoff into nearby streams and rivers in order to avoid flooding. However, most of these structures frequently fail to serve the intended use due to the occurrence of high intensity rainfall accompanied with long duration, which produce runoff discharge higher than their designed capacities. This is common in many developing countries as drainages and culverts are most times constructed without considering hydrological analysis of the catchment. Hence, this research considered Port Harcourt city as a case study by utilizing 50 years …

Real-Time Complex Hand Gestures Recognition Based On Multi- Dimensional Features, Isack Bulugu

Tanzania Journal of Engineering and Technology (TJET)

Gesture recognition is broadly utilized within the field of sensing. There are basically three gesture recognition methods based on computer vision, depth sensor and motion sensor. Motion sensor-based gesture recognition has few input data, fast speed, and direct access to three- dimensional information of the hand. The advantages of traditional motion sensor-based gesture recognition have gradually become a current research hotspot. The essence of traditional motion sensor-based gesture recognition is a pattern recognition problem, and its accuracy depends heavily on the feature dataset extracted from prior experience. Unlike traditional pattern recognition methods, deep learning can be used to a large …

Economic Analysis Of Islanded Microgrid: A Case Study Of Kisiju Village - Coastal Region, Jackson Justo

Tanzania Journal of Engineering and Technology (TJET)

The concept of Microgrid (MG) has gained significant attention of researchers and projects on the business side of electrical power generation and utilization, particularly in electrification of islanded areas such as villages. Most of these microgrids are powered by renewable energy resources (RERs) and they distribute power in low voltage distribution networks. Hence, these systems are faced with reliability problems due to the intermittency nature of RERs which affect the technical as well as the return on Investment of specific projects. In the latter context, reliability and economic analysis of the MG systems is an inevitable choice. This paper presents …

Complete Neighbourhood Search Heuristic Algorithm For Portfolio Optimization, Collether John

Tanzania Journal of Engineering and Technology (TJET)

In portfolio optimization, the fundamental goal of an investor is to optimally allocate investments between different assets. Mean-variance optimization methods make unrealistic assumptions to solve the problem of optimal allocation. On the other hand, when realistic constraints like holding size and cardinality are introduced it leads to optimal asset allocation which differ from the mean variance optimization. The resulting optimization problem become quite complex as it exhibits multiple local extrema and discontinuities. Heuristic algorithms work well for the complex problem. Therefore, a heuristic algorithm is developed which is based on hill climbing complete (HC-C). It is utilized to solve the …

Ahp Based Multi Criteria Decision Analysis Of Success Factors To Enhance Decision Making In Infrastructure Construction Projects, Solomon Belay, James D. Goedert, Asregedew Woldesenbet, Saeed Rokooei

Durham School of Architectural Engineering and Construction: Faculty Publications

The study presents analytical data-based multi-criteria approach of critical success factors of infrastructure construction projects analyzed in the Ethiopian construction industry. This multi-criteria technique helps to improve the decision capabilities and ultimate performance of construction processes in various low-income countries of the East African region. The aim of this paper is to establish a logical relationship and interdependencies of success-related factors for enhancing decision making for various project teams and identify priorities while taking into account all known construction organizational constraints. A structured hierarchical matrix was developed based on a pre-identified success-related factors, and initially evaluated by experienced professionals as …

Examining Factors Influencing Intention To Use M-Health Applications For Promoting Healthier Life Among Smartphone Users In Tanzania, Herman Mandari, Mahija Yahaya

Journal of International Technology and Information Management

Deaths related with Non-Communicable Diseases (NCDs) have recently increases, similarly, development of mobile technologies have paved a way in which Smartphone users can use m-health applications to address high level of sedentary behaviours that relates to negative health consequences. Therefore, this study was conducted to examine factors which may influence generation Y who are Smartphone users to adopt m-health applications in controlling NCDs in Tanzania. TAM theory was extended with awareness, trust and perceived cost to develop a research conceptual model of this study. Google form was used to developed online questionnaire which was distributed through social media platforms to …

Optimal Design Of Hybrid Renewable Energy For Tanzania Rural Communities, Ester T Marcel, Joseph Mutale, Aviti T Mushi

Tanzania Journal of Science

Rural communities in developing countries lack access to electricity due to high costs of grid extension. This paper proposes a hybrid system of renewable energy (HRES) as solution. The HRES consists of solar, wind, and battery energy storage (BES). The village called Ngw’amkanga in Shinyanga region of Tanzania, East Africa is selected as a case study. An iterative method to determine the size of wind and solar photovoltaic (PV) generation required assuming a project life of 25 years at minimum annualised cost of the system ( ) is proposed. The project life time is fixed on the life span of …

Critical Analysis Of Material Consumption And Cost Reduction Techniques For The Apparel Cutting Processes, Ismael Taifa, Ibrahim Twaha, Mboka A Mwakibambo

Tanzania Journal of Science

Revenues generation in the garment industry is synonymous with material consumption. This study thus analysed material consumption and cost reduction techniques in the Tanzanian garment industry. The research employed quantitative (experimentation) and qualitative approaches (document review and observation technique) in the apparel cutting processes. Experimental results of material consumption from ten tests averaged efficiency of 78.67%, the wasted pieces (19.2%), and unnoticed waste (2.03%). Essential considerations to reduce material waste include: digitalising the fabric cutting processes; providing workers training; deploying appropriate practices in the cutting room (e.g. pattern engineering and pattern accuracy); considering the quality of the procured fabric and …

Pair Distribution Function Analysis And Electrochemical Performance Of Mesoporous Carbon Nanomaterials Synthesized Through Koh And Zncl2 Activation, Talam E. Kibona, Sarah Frisco, Maxwell W. Terban

Tanzania Journal of Science

Mesoporous carbon has been synthesized by activating carbonized biogas slurry residues with ZnCl2 and KOH simultaneously. The carbon to activating agent mass ratios were kept at 1:4, while the ZnCl2 to KOH mass ratio varied from 4:0, 3:1, 2:2, 1:3, to 0:4. The highest BET specific surface area of 361 m2 g-1, micropore surface area of 231 m2 g‒1, mesopore surface area of 125 m2 g‒1, and total pore volume of 0.23 cm3 g‒1 which amounted to 78% mesopore content, were obtained for the sample with 3:1 ZnCl2 to KOH mass ratio. Scanning electron microscope (SEM) images were acquired to …

Advances In Nanomaterials Sciences And Nanotechnology For Sustainable Development: A Review, Gervas E. Assey, Wilhelm S. Malasi

Tanzania Journal of Science

The fields of materials sciences have great opportunities to address the challenges of sustainable development of modern societies. The sub-disciplines of materials sciences of interest in this review are nanomaterials sciences and nanotechnology. Nanomaterials possess one external dimension measuring 1-100 nm. They have larger surface area for the same mass than their bulk materials. They are more reactive with effects on their electrical, optical and magnetic properties. Thus, nanomaterials are promising for sustainable development in the areas of energy, water, chemicals, electronics, medical and pharmaceutical industries, CO2 mitigation and agriculture. To this end, this review explores the advances in nanomaterials …

The Possible Use Of Telemedicine In Developing Countries, R. Wootton

Online Journal of Space Communication

Since the place of telemedicine in the industrialized world is by no means properly worked out yet, it might seem premature to consider its use in developing countries. Nonetheless, there is interest in the possible use of telemedicine in developing countries, from at least two organizations:

1. The Midjan group, an impromptu committee that was formed following the African Regional Telecommunications Development Conference in Abidjan in March 19963. This European telemedicine collaboration group aims to explore the use of telemedicine in developing countries. At present, the group includes representatives from 22 telecommunication and medical informatics suppliers, telecommunication operators, universities, hospitals and …

Maintenance Automation Architecture And Electrical Equipment Fault Prediction Method In Tanzania Secondary Distribution Networks, Hadija Mbembati, Kwame Ibwe, Baraka Maiseli

Tanzania Journal of Science

Distribution networks remain the most maintenance-intensive parts of power systems. The implementation of maintenance automation and prediction of equipment fault can enhance system reliability while reducing the overall costs. In Tanzania, however, maintenance automation has not been deployed in secondary distribution networks (SDNs). Instead, traditional methods are used for condition prediction and fault identification of power assets (transformers and power lines). These (manual) methods are costly and time-consuming, and may introduce human-related errors. Motivated by these challenges, this work introduces maintenance automation into the network architecture by implementing effective maintenance and fault identification methods. The proposed method adopts machine learning …

Analysis And Performance Evaluation Of Entropic Thresholding Image Processing Techniques For Electrical Capacitance Tomography Measurement System, Josiah Nombo, Alfred Mwambela, Michael Kisangiri

Tanzania Journal of Science

To improve image quality generated from the electrical capacitance tomography measurement system, the use of entropic thresholding techniques is investigated in this article. Based on the analysis of the principle of Electrical Capacitance Tomography (ECT) image reconstruction and entropic thresholding, various algorithms have been proposed for easy extraction of quantitative information from tomograms generated from the ECT system. Experiments indicate that proposed algorithms can provide high-quality images at no or minimum computational cost. It is easier to implement and integrate with classical algorithms such as Linear Back Projection, Singular value decomposition, Tikhonov regularization, and Landweber. Entropic thresholding techniques present a …

Assessment Of The Impacts Of Climate Variability On Hydropower Generation: A Case Study Of The New Pangani Falls, Tanzania, Dativa Byarufu

Tanzania Journal of Engineering and Technology (TJET)

Climate change poses potential impacts on hydropower generation either positively by increasing or negatively by decreasing river flow. This study assessed the impacts of climate variability on hydropower with a focus on the New Pangani Falls in Tanzania. Rainfall and temperature time series data from 1980-2014 were analyzed in relation to river discharge and associated impacts to hydropower generation. The Man-Kendall test was used to detect trend in both annual and seasonal time series. The results showed a negative trend in annual rainfall with Z= -2.41 at α = 0.05 and the slope Q = -0.964. Seasonal trend analysis showed …

Rheological Properties Of Aged Crude Hard Wood Pyrolysis Oil, Divina D. Kaombe

Tanzania Journal of Engineering and Technology (TJET)

Upon storage of the pyrolysis oil, aging reactions may initiate phase separation and change of the rheological properties. These changes lead to unfavourable fuel characteristics in handling, transportation and applications. Efforts have been made for alleviation including methods on how to avoid these aging effects and development of equipment capable of handling aged pyrolysis liquids with unfavourable fuel characteristics. Therefore, the aim of this study was to explore the rheological properties of phase separated pyrolysis liquid fuel. Two batches of a well – stored poplar wood pyrolysis oils were used for the investigation; one batch was diluted with water to …

Performance Of Calcium Chloride- Ammonia Adsorption Refrigeration System, Michael John

Tanzania Journal of Engineering and Technology (TJET)

An experimental study on the performance of calcium chloride-ammonia adsorption system is described. A single bed water cooled condenser adsorption refrigerator prototype, which utilises calcium chloride-ammonia pair has been developed and tested in the laboratory. Experiments have been conducted for desorption temperatures of 100 °C with desorption time varying from 1 to 4 hours. An electric tape heater and a timer were used to perform the experiments. The adsorption temperature profile, adsorption rate and prototype performance have been analysed and discussed. The tested heating and desorption temperature of 100 °C and heating and desorption time of 1 to 4 hours …

Prediction Of Uniaxial Compressive Strength Of Granite Rock Samples Of Lugoba Quarry Using Rebound Hammer Test, Moses Kongola, Karim Baruti

Tanzania Journal of Engineering and Technology (TJET)

Rebound hammer test is widely used as an indirect measure of uniaxial compressive strength for engineering materials such as concrete, soil, and rock in both civil and mining engineering works. In quarries, uniaxial compressive strength is a crucial parameter in the analysis of geotechnical problems involving rock stability and rock blasting design. This study aims at establishing the empirical models of uniaxial compressive strength fits on rebound hammer number that can be used to predict uniaxial compressive strength of granitic rock at Lugoba Quarry. Data for direct uniaxial compressive strength were obtained from uniaxial compressive strength test carried out on …

Prediction Of Four-Days Soaked California Bearing Ratio (Cbr) Values From Soil Index Properties, Pascal Ambrose, Siya P. Rimoy Dr

Tanzania Journal of Engineering and Technology (TJET)

California Bearing Ratio (CBR) laboratory testing is the conventional method for determining soaked strengths of pavement subgrades. The test requires careful preparation of soil samples followed by four days of water soaking before penetrating the samples using a standard plunger at prescribed rates to set depths. When the number of samples becomes large the determination of soaked CBR values becomes cumbersome as the test is laborious and time consuming. This study aimed at establishing an alternative way of determining soaked CBR by developing a model that would be used for estimating soaked CBR of fine- and coarse- grained soils without …

Socio-Technical Perspective For Electronic Tax Information System In Tanzania, Lucas Ngowi, Ellen Kalinga

Tanzania Journal of Engineering and Technology (TJET)

Socio-technical systems theory has rarely been used by system architects in setting up computing systems. However, the role of socio-technical concepts in computing, which is becoming social in nature, has made the concepts more relevant and commercial. Tax information systems are examples of such systems because they are influenced by external variables such as the political environment, technological trends, and social environment, introducing complexity in their deployment and determining the type of e-services and their delivery to a diverse group of people. It was observed that in Tanzania there is resistance, reluctance and minimal use of electronic tax system because …

Overview: Politics And Technology Converge: Case Studies On The Effects Of Regulatory Reform On Vsat Adoption In Developing Countries, Emmanuel Adugu, Kwasi Boateng, D. Flournoy, Eric Gavua, Wencelous Kaswoswe, Miao Zhang

Online Journal of Space Communication

Developing countries are actively implementing satellite data networks, and have undertaken policy reforms to facilitate such networks. This research examines how regulatory changes have resulted in the removal of barriers relating to the deployment of access technologies and growth in connectivity, especially in VSAT installations for low cost Internet access. In addition, this research seeks to identify the socio-economic impact of emerging data network applications in government, business, health and education. In some cases, government offices have been the driver of change; in other cases, businesses have been the ones to initiate and press these developments forward.

Copper Slag As A Potential Waste Filler For Polyethylene-Based Composites Manufacturing, Aleksander Hejna, Paulina Kosmela, Mateusz Barczewski, Olga Mysiukiewicz, Adam Piasecki

Tanzania Journal of Science

The present study aimed to analyze the application of waste material from copper production– copper slag (ŻŻL) as filler for composites based on the high-density polyethylene (HDPE). Copper slag filler was introduced in the amounts of 1–20 wt%, and its influence on the appearance (color analysis), chemical structure (Fourier-transform infrared (FTIR) spectroscopy), microstructure (optical microscopy), as well as static (tensile tests) and dynamic (dynamical mechanical analysis (DMA)) mechanical properties of composites were investigated. Proper dispersion of filler implicated that the incorporation of up to 5 wt% of filler caused only slight, 5% drop of tensile strength, with the simultaneous 16% …

Upgrading Biogas Using Eburru Zeolitic Rocks And Other Adsorbent Materials To Remove Carbon Dioxide And Hydrogen Sulphide, James K Mbugua, Joseph M Mwaniki, Damaris M Nduta, Francis B Mwaura

Tanzania Journal of Science

The trace amounts of carbon dioxide and hydrogen sulfide in raw biogas lower its calorific value,cause corrosion and make it hard to compress biogas into the cylinder. Raw biogas was obtainedfrom anaerobic digestion of cow dung and market wastes. The gas was stored in tubes or urine bagbefore upgrading. Natural zeolite rocks, maize cobs, steel wire, desulphurizer, and worn-out tyreswere used as the upgrade materials. The composition of biogas was recorded before and afterupgrading using a GP180 portable biogas analyzer from Henan, China. The measured level of rawbiogas was 0.0227% H2S, >20% CO2 and 52-56% CH4. The most efficient upgrade …

Assessment Of Natural Radioactivity And Radiation Hazards Of Building Materials In Kinondoni District, Dar Es Salaam, Tanzania, Huruma P Mammba, Vitus A Balobegwa, Alex P Muhulo, Peter A Pantaleo, Remigius A Kawala

Tanzania Journal of Science

Natural radionuclides from building materials are one of the potential sources of external as well as internal radiation exposure to the human body. Currently, this exposure has been increasing since people spend more than  of their time indoors (ICRP 1991). Commonly used building materials from Kinondoni District were investigated using γ-spectrometry; their activity concentrations of 226Ra, 232Th and 40K in Bq/kg were measured. The results showed that average values of activity concentrations of 226Ra, 232Th and 40K were 15.62, 21.51 and 237.99 Bq/kg, respectively. All the activity concentrations in the studied samples were lower than the world average values of …