Electrical and Computer Engineering Commons^™

Development Of An Ann-Based Predictive Model For The Efficient Treatment Of Industrial Wastewater, Alisher Khudoyberdi Ugli Rakhimov, Hasan Siddiq Ugli Murodov, Farrukh Bakhtiyorovich Igitov, Shuhrat Ahmadjonovich Mutalov, Jaloliddin Abdurazzakovich Eshbobaev

Chemical Technology, Control and Management

The effective removal of free chlorine ions from industrial wastewater is critical to ensure process safety, minimize equipment corrosion, and protect aquatic environments. In this study, a laboratory-scale activated carbon filtration system was developed and tested to treat chlorine-contaminated water collected from sludge collectors at industrial facilities. A total of 200 experimental trials were conducted under varied operational conditions, including changes in flow rate, initial chlorine concentration, pressure, pH, temperature, and activated carbon dosage. The resulting dataset was used to train a predictive model based on a feedforward backpropagation artificial neural network (ANN) implemented in MATLAB. The ANN model demonstrated …

Data-Driven Constrained Control, Ali Kashani

Mechanical Engineering ETDs

Ensuring safety is a fundamental challenge. Traditional methods often rely on precise mathematical models, which are difficult, impractical, or costly to obtain for real-world systems with complex, nonlinear dynamics. This dissertation develops direct data-driven control approaches that enable safe and efficient operation of nonlinear systems without requiring explicit models or performing system identification. This effort leverages machine learning, optimization, and control theory to bridge theoretical rigor and practical applicability. Deterministic guarantees are provided based on the Lipschitz continuity of the system, and probabilistic guarantees through scenario optimization. The computation of safe sets is performed using one-shot approaches with broad neural …

Thermal Energy Storage System Using Silica Sand As Heat Storage Medium: Simulation Of Geita Gold Mine, Santos Kihwele

Tanzania Journal of Engineering and Technology (TJET)

Currently, Geita Gold Mine (GGM) relies on electrical energy from the national grid and diesel power generators to generate electricity for various industrial applications. The plant currently spends a large amount of money on generating power from diesel generators. The total annual cost of power generation from diesel generators including lubricants is USD 56,057,990. The total annual fuel cost is USD 53,531,805 for a total of 54,985,473 liters per year. Most of the power generated by the generators is consumed in the industrial thermal processes. Thermal energy applications at the plant are thermal drying of the extracted ores to remove …

Development And Experimental Validation Of A Non-Invasive Blood Group Detection System, Nurath K. Nurudini

Tanzania Journal of Engineering and Technology (TJET)

An individual's blood group consists of red blood cell antigens whose composition is determined by protein presence, antigen structure, and gene series. Persons aged above six months have significant anti-A and/or anti-B in their serum. During transplantation and transfusion, ABO blood group identification is the most essential factor. The conventional method involves drawing blood samples from patients, and the blood group is determined based on the antigen-antibody reaction. This method consists of adding chemical reagents. However, this requires time of operation, and throughput analysis is high, and the process is also challenging to interpret. Accurate and rapid identification of blood …

A Review Of Lithium-Ion Battery Capacity Fade Deceleration At Power Fluctuations In Renewable Energy Systems, Isaac Gwayi

Tanzania Journal of Engineering and Technology (TJET)

Application of lithium-ion (Li-ion) batteries to store energy in renewable energy systems (RESs) is increasing due to their promising properties. Therefore, it is crucial to understand aging behaviours of Li-ion battery during RES life time as this directly affects cost of energy. Li-ion battery aging can be categorised into calendar aging and cycle aging. Calendar aging depends mainly on temperature and state of charge (SoC). In addition to temperature and SoC, cycle aging depends also on charge and discharge current rates and cut-off voltages. Higher current rates lead to faster Li-ion battery aging. It is necessary to identify appropriate battery …

Towards Effective Academia-Industry Collaborations: The Case Of Higher Learning Institutions In Tanzania, Fatuma S. Ikuja

Tanzania Journal of Engineering and Technology (TJET)

Industries are the main consumers of products from higher learning institutions (HLIs); graduates for employment and research outputs for socio-economic development. Research outputs from HLIs are commercialized as services or products facilitated by academia-industry collaborations. The collaborations are expected to address mismatch between labour market needs and HLIs’ products, which has resulted in graduates’ employability challenges. Despite their importance, effective academia-industry collaborations remain challenging. This study explores the effectiveness of Academia-Industry collaborations established by HLIs in implementing the Higher Education Economic Transformation (HEET) project (2021-2026) in Tanzania. One of the project objectives is to build functional linkages between industry and …

Advancements In Refreshable Braille Display Technology: A Comprehensive Survey, Maryam Etezad, Rajeev Joshi, Franceli L. Cibrian

Engineering Faculty Articles and Research

This paper provides a comprehensive mapping literature review of the advancements in refreshable Braille display (RBD) technology, which employs dynamically movable pins or dots to render Braille characters for individuals with blindness and visual impairment. This literature review, which includes 96 papers, aims to summarize the current evidence on six distinct types of RBDs: piezoelectric, electromagnetic, electroactive polymer (EAP), pneumatic, shape memory alloy (SMA), and microfluidic technologies. For each type, we discuss the underlying mechanisms, alongside the current trends and research opportunities. This comparative analysis aims to inform the selection of appropriate RBD technology based on specific user needs and …

Optimal Placement Of Distributed Generation Units In Power Distribution Networks Using Particle Swarm Optimization, Owdean M. Suwi

Tanzania Journal of Engineering and Technology (TJET)

Power losses and voltage drops in distribution networks are critical issues in power system operation, reducing efficiency, reliability, and overall quality of the power supply to customers. Additionally, the rising electricity demand, deregulation of energy markets, and congestion in transmission networks have further contributed to the declining performance of the grid. To address these challenges, integrating distributed generation units (DGUs) into electric distribution systems has gained significant attention. Furthermore, the integration of DGUs into conventional fossil fuel-based power plants is becoming necessary to reduce greenhouse gas emissions. However, proper placement and sizing of DGUs are crucial for achieving optimal benefits. …

Potential Use Of Pump As Turbine Coupled To Self-Excited Induction Generator For Micro-Hydro Cooking And Cooling Applications, Emanuel J. Nyirenda

Tanzania Journal of Engineering and Technology (TJET)

Clean cooking and efficient cooling in developing countries have recently become areas of great focus. Further, the environmental impact of flooding in high-capacity hydroelectric plants has become a major concern. As a result, there is growing emphasis on developing sustainable and decentralized energy solutions, focusing on the potential of micro-hydro systems, especially in rural and remote areas. Although there are several alternative energy generation methods, their application is not straightforward. One of the latest technologies under research is using pumps as turbines coupled to an induction generator. This paper explores through a rigorous experimental approach the possibility of using a …

Assessment Of Maintenance Performance Level Of Selected Hydropower Plants In Tanzania, Mahamudu H. Mtebwa

Tanzania Journal of Engineering and Technology (TJET)

Despite significant progress in increasing electricity access to over 78%, electricity reliability in Tanzania remains a concern, with frequent power outages reported. Maintenance issues in hydropower plants have been identified as a critical factor contributing to this problem. However, the specific maintenance performance levels have not been fully assessed. This study conducts a comprehensive evaluation of the maintenance performance of four key hydropower plants: Kidatu (204 MW), Kihansi (180 MW), Mtera (80 MW), and New Pangani Falls (68 MW). Data collected from staff surveys and maintenance records between 2018 and 2022 were used in the study. Although staff demonstrated a …

The Impacts Of Renewable Energy Sources: A Review On Grid Inertia And Frequency Regulation, Sospeter Gabriel

Tanzania Journal of Engineering and Technology (TJET)

The power system is gradually transitioning into low inertia due to integrating substantial intermittency quantity of converter-based renewable energy sources, such as wind and photovoltaic power, into the current power grid network. This integration presents significant inertia and frequency control challenges to the network as a result of a decrease in the percentage of synchronous generators. Moreover, faster frequency deviations are posed by the mismatch between the supply and demand during contingencies, which creates difficulties in preserving the frequency stability of the power system. This research explores the impacts of renewable energy sources (RESs) on grid inertia and frequency management …

Review On Gas-To-Liquids Conversion Technology: Lessons From Case Studies And Potential Strategies For Implementation In Tanzania, Joseph H. Kihedu

Tanzania Journal of Engineering and Technology (TJET)

This review paper explores the transformative potential of Gas-to- Liquids (GTL) technology for harnessing Tanzania's vast natural gas resources. With significant discoveries of natural gas reserves totalling up to 57 Tcf in fields such as Songosongo, Mnazi Bay, Block 1, 2, 3 and 4. Tanzania is positioned to leverage GTL technology to convert these resources into high-value liquid fuels like gasoline, diesel and naphtha. Review of GTL process, its products and applications has been done. By analysing successful GTL projects globally and drawing lessons applicable to Tanzania, this paper provides strategic recommendations for policymakers and stakeholders to foster GTL development. …

Analysis Of An Improved Reliability Dual-Buck Structured Three-Level Flying Capacitor Inverter, Almachius Kahwa Dr.

Tanzania Journal of Engineering and Technology (TJET)

With the increased demand for high-reliability power converters in the electric drive-train and propulsion systems, the efforts to design and analyze converters with high fault tolerance have become apparent. Among the emerging trends to improve the reliability of power converters is the incorporation of dual-buck (DB) structures in traditional converter topologies. Thus, this paper studies a single-phase dual-buck structured three-level flying capacitor (FC) inverter. The dual-buck flying capacitor (DBFC) inverter was constructed in such a way as to suppress the shoot-through problems that may occur because of the switching mismatch and gate driver delay, as exhibited in the traditional FC …

Mitigation Of Voltage Disturbances In Industrial Power Distribution Networks Using Dynamic Voltage Restorers, Aviti T. Mushi

Tanzania Journal of Engineering and Technology (TJET)

Most electrical and electronic equipment in industries require high-quality power to function efficiently. Nonetheless, voltage sags and swells are pressing concerns and prone to directly impact the economy of industrial customers. One such customer embattled with these problems is Mbeya Cement Company Limited (MCC) located in Mbeya, Tanzania. These issues mainly are caused by upstream faults and switching operations. One way to address these is by utilizing the voltage injection method, which employs a power device known as a dynamic voltage restorer (DVR). In this paper, the voltage sags and swells of balanced three-phase, unbalanced double-line and single-line to ground …

Calibration Of Measurement Tools In The Experimental Test Rig For Hydropower Performance Evaluation, Ombeni J. Mdee

Tanzania Journal of Engineering and Technology (TJET)

The demonstration of a typical hydropower plant requires the development of a test rig with the installation of tools to measure the performance parameters. The measurement tools require a calibration process to improve the quality of recorded data. This study involved the calibration of traditional and automated measurement tools connected to the hydropower test rig through an Arduino microprocessor. The automated measurement tools included a pressure transducer, flow meter, digital tachometer, and torque transducer, while traditional measurement tools, including a pressure gauge, concrete water tank, contact tachometer, and force lever arm balance, were connected in the same test rig during …

Energy Optimal Coverage Motion Trajectory Generation Using A Fourth-Order Motion Profile, Mathias Halinga

Tanzania Journal of Engineering and Technology (TJET)

Industrial machines are widely used in manufacturing sector to manufacture several products to meet customer demands. Most of these industries runs all the time throughout a day leading to high operating cost. To cut costs and satisfy customer demand for precise products, industrial machines’ motion generation is important in improving machine motion precision while using less energy. This study presents a coverage motion energy optimization which is generated by linear interpolation of each segment described by the fourth-order motion profile. The phase changes in the profile are attained with continuity of machine kinematic limits jerk, acceleration, and velocity, which are …

Prospects Of Clean Cooking Energy In Africa - Transition Pathways And Implications, Joseph H. Kihedu Dr.

Tanzania Journal of Engineering and Technology (TJET)

Despite abundant renewable energy resources, African countries still suffer from energy poverty, particularly in cooking. Up to 2022, about 74% of the African population had no access to clean cooking energy. With focus to Sub-Saharan African population, 90% has no access to clean cooking energy which decrease by 7% when kerosene is included. Traditional cooking, which involves the use of charcoal and firewood, is associated with health problems, environmental degradation, socioeconomic issues, and gender inequality. Transitioning to clean cooking energy not only promises significant health benefits but also offers opportunities for sustainable economic development and environmental preservation. In this study, …

Evaluation Of Thermal And Emission Performances Of Briquettes Produced From Carbonized Corn Cob And Corn Husk, Karina S. Motani

Tanzania Journal of Engineering and Technology (TJET)

The Mozambican agro-industrial sector relies heavily on various crops, with maize being the most significant. During processing, substantial waste is generated, which is often discarded as organic matter or burned, contributing to environmental pollution and the loss of potential energy resources. This study evaluated the thermal and emission performance of briquettes made from carbonized corn cob (CCC) and carbonized corn husk (CCH), using cashew nut skin as a binder for clean cooking applications. The briquettes were assessed against firewood and charcoal as control fuels, focusing on several energy performance parameters: water boiling time (WBT), combustion index (CI), thermal efficiency (TE), …

The Dynamics Of Word-Of-Mouth Marketing: An Agent-Based Modeling Approach To Message Credibility And Consumer Engagement, Ali Nasirzonouzi, Carlos Gershenson

Northeast Journal of Complex Systems (NEJCS)

Word-of-mouth (WOM) marketing is a critical factor in the dissemination of information and adoption of products in social networks. This paper investigates the impact of two important factors message credibility and consumer engagement on WOM adoption dynamics using agent-based modeling (ABM). This study proposes a simple qualitative model to investigate how these factors influence adoption rates through both broadcast communication and peer-to-peer influence by simulating interactions on a spatially clustered network.

The findings show that increased message credibility significantly boosts adoption, achieving a balance between broadcast and social mechanisms. Also, consumer engagement primarily affects the adoption mechanism, shifting the effect …

Carbon Efficiency Of Natural Organic Honey-Memristor Based Neuromorphic Computing, Harshvardhan Uppaluru, Zoe Templin, Shah Zayed Riam, Feng Zhao, Jinhui Wang

Electrical and Computer Engineering Faculty Research & Creative Works

Natural organic memristors manufactured using honey have exhibited promising synaptic behavior, offering notable advantages such as environmental sustainability, low production and disposal costs, non-volatile storage capabilities, and bio/CMOS compatibility. In this paper, experimental evaluations of honey-memristor based neuromorphic systems are reported with a focus on estimating their carbon footprint. First, manufacturing and testing of honey-memristors is briefly described. To suppress variations and improve accuracy, an optimization technique - parallel memristors is applied. Experimental results indicate that this optimization method significantly improves the device performance of up to. However, it also leads to higher energy consumption and a higher carbon footprint …

Redox-Active Monolayers On Ito Prepared By Post-Amidation And Direct Esterification And Their Spectroelectrochemical Characterization, Takamasa Sagara, Sae Nakai, Ryusuke Yofu, Shota Kojin

Journal of Electrochemistry

A redox-active monolayer on an optically transparent electrode constitutes a typical platform for spectroelectrochemical sensing. The necessity for its sophistication arises from the availability of multi-dimensional sensing signals. Simultaneous monitoring of the redox current and color change synchronized with the oxidation state change significantly enhances sensitivity and selectivity. This study aimed to elucidate the modification of an indium tin oxide (ITO) electrode with a viologen monolayer with an ordered orientation. Novel methods were developed to immobilize a viologen molecule bearing a carboxyl group to form assembled monolayers through a condensation reaction using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide with N-hydroxy-succinimide (EDC/NHS). In the two methods …

Ambient Co2 Capture And Valorization Enabled By Tandem Electrolysis Using Solid-State Electrolyte Reactor, Yan-Bo Hua, Bao-Xin Ni, Kun Jiang

Journal of Electrochemistry

Electrocatalytic carbon dioxide reduction is a promising technology for addressing global energy and environmental crises. However, its practical application faces two critical challenges: the complex and energy-intensive process of separating mixed reduction products and the economic viability of the carbon sources (reactants) used. To tackle these challenges simultaneously, solid-state electrolyte (SSE) reactors are emerging as a promising solution. In this review, we focus on the feasibility of applying SSE for tandem electrochemical CO₂ capture and conversion. The configurations and fundamental principles of SSE reactors are first discussed, followed by an introduction to its applications in these two specific areas, …

A Yolo-Based Deep Learning Approach For Vibration-Based Rotating Shaft Imbalance Detection, Abdelhameed Zayed Dr., Ali Siam Dr.

Journal of Engineering Research

One of the prevailing causes of vibrations in machines is rotor imbalance. Rotor balancing can be used to fix the majority of rotating machinery issues. When it comes to high-speed running equipment, even a slight imbalance can lead to serious issues and decrease the operational efficiency of rotating machinery. This work proposed a deep learning approach for the detection of binary and multiclass imbalance in rotating shafts. A YOLOv11 model-based approach is developed to detect imbalance and identify unbalanced rotor positions. To precisely identify unbalanced positions, this method trains the YOLOv11 model using numerous sets of measured response data and …

Impact Of Gamma-Ray Dose On Indoor Visible Light Communication Link Performance: A Geant4 Study, Fayza Mohamed Elamrawy, Adel Mohamed Ismail, Hossm Kasem Prof, Salah Khamis Prof, Ahmed Abdelaziz Youssef Prof

Journal of Engineering Research

This research presents an extended performance analysis of an indoor Visible Light Communication (VLC) system by integrating experimental results with advanced GEANT4 simulations. Building on a prior empirical study that evaluated different LED configurations and photodetectors, this work explores critical environmental and spatial parameters that influence VLC efficiency and reliability. Parameters such as wall reflectivity, emission angles, photon energy, and photon travel time are systematically analyzed using a validated GEANT4 simulation framework. The results confirm the strong impact of narrow emission angles and high wall reflectivity on detection performance, while also highlighting the importance of time delay modeling in high-fidelity …

Multi-Modal Covid-19 Detection Using Cough Sounds And Medical Information With Attention-Enhanced Deep Learning, Mohamed Talaat Saidahmed, Reda Elbasiony, Marwa Reda Bastwesy, Asmaa Aly Hagar

Journal of Engineering Research

The COVID-19 pandemic has highlighted the need for fast, non-invasive, and cost-effective diagnostic tools. Cough sounds, as a prominent symptom of respiratory diseases, present a promising modality for automated COVID-19 detection. In this study, we propose a novel multi-modal deep learning framework for COVID-19 detection that leverages cough sounds and patient-specific medical information. Our approach extracts two types of acoustic features—Mel-Frequency Cepstral Coefficients (MFCCs) and Mel spectrograms—and integrates them with clinical metadata to improve diagnostic ac-curacy. The MFCC branch employs 1D convolutional layers followed by Efficient Channel Attention mechanism. The Mel spectrogram branch utilizes ResNet-50 combined with ECA to capture …

Mutual Coupling Impedance Effect On Ris-Assisted Terahertz Communication, Radwa A. Roshdy Dr., Hossam M. Kasem Prof., Mohammed A. Salem Dr.

Journal of Engineering Research

Terahertz (THz) communication based on reconfigurable intelligent surfaces (RIS) is a promising technology in future wireless networks, with the capabilities of ultra-high data rates and energy-efficient beam communicating. Nevertheless, the mutual coupling impedance of the closely spaced RIS reveals the inefficacy in existing channel estimation schemes, while it is usually ignored in the literature. In this paper, we fill this gap by developing an EM-compliant channel model that integrates mutual coupling explicitly for RIS-assisted THz systems. We evaluate the performance of mutual impedance-induced influence to the accuracy of the root mean square error (RMSE), which is considered as a pivotal …

Performance Enhancement Of Ev Drive System Under Open-Phase Fault Using Reinforcement Learning With Mpc, Ahmed M. Hassan, Mohammed E. Metwally Dr.

Journal of Engineering Research

Improving the operation of electric vehicles (EVs) under fault is a very important subject because it increases their ability to operate in case of an emergency. This paper proposes a fault-tolerant control methodology for an EV drive system under open phase fault (OPF). The 5-ph interior permanent magnet synchronous motor (IPMSM) is employed in the drive system because it has several merits, such as high efficiency and reliability. The proposed technique is based on utilizing a reinforcement learning (RL) control algorithm, based twin-delayed deep deterministic policy gradient (TD3) algorithm, to operate the motor at maximum torque per ampere under OPF. …

Dynamic Resource Allocation For Wireless Networks And Radar Systems Via Deep Reinforcement Learning, Ziyang Lu

Dissertations - ALL

The rapid advancement of wireless communication technologies and the proliferation of smart devices have led to increasingly complex and dynamic network environments. These developments have posed significant challenges to traditional radio resource management (RRM) techniques, which often struggle with scalability, adaptability, and real-time decision-making. In response to these limitations, this dissertation explores the application of advanced machine learning, particularly deep reinforcement learning (DRL), to develop intelligent, adaptive, and data-efficient solutions for resource management in wireless networks and radar systems. We begin by addressing joint channel access and power control in wireless interference networks using centralized, distributed, and federated multi-agent DRL …

Grades Are Bugs, Jordan Freitas

Computer Science Faculty Works

This paper argues that grades are bugs in our educational system, undermining desired behaviors and outcomes. Grades were introduced into higher education for purposes directly at odds with the goals of inclusive pedagogy today, as well as the neuroscience of human motivation and learning. Students enter computer science programs from increasingly varied backgrounds and experiences, and face a rapidly evolving landscape of prospective career paths while higher education costs in the United States are ever increasing. Computer science educators have a responsibility to adapt and carefully re-examine typical approaches to all aspects of the learning environments we build and curricula …

Grid Fragility, Blackouts, And Control Co-Design Solutions, Mario Garcia-Sanz

Faculty Scholarship

The grid is undergoing a large-scale transformation, including a significant reduction of synchronous generators, a high penetration of inverter-based resources and renewables, substantial demand growth, new extra-large loads, aging infrastructure and a concerning vulnerability to contingencies. Some of the recent massive blackouts in Spain/Portugal, Chile and Texas are exposing the fragility of the grid as we know it today. This paper introduces new solutions to stabilize the grid under undesired dynamic interactions and extreme contingencies, with the goal of avoiding cascading failures and blackouts. Using control co-design methodologies, the paper proposes three interdependent categories to improve the reliability and controllability …