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A Mathematical Model On The Temporal Dynamics Of Aviation Competitive Pricing, Tichaona Chikore,, Farai Nyabadza, Oct 2025

A Mathematical Model On The Temporal Dynamics Of Aviation Competitive Pricing, Tichaona Chikore,, Farai Nyabadza,

Journal of Aviation/Aerospace Education & Research

This study investigates the competitive dynamics of airport pricing using U.S. airport data to validate the findings. It employs linear and nonlinear ordinary differential equation models to analyze the influence of competitive interactions and internal factors on pricing decisions. The methodology involves parameter estimation via optimization techniques and quantile regression to capture heterogeneity across market segments. Mathematical analysis and simulation results show that if competitive coupling coefficients are low then there is weak competitive influence on pricing, with airports’ pricing largely driven by internal factors. Also, if the adjustment rates exhibit consistency across airports then internal dynamics are dominant in …


Flow Structure And Mixing Near A Small River Plume Front: Winyah Bay, Sc, Usa, Christopher Papageorgiou, George Voulgaris, Alexander E. Yankovsky, Diane Bennett Fribance Oct 2025

Flow Structure And Mixing Near A Small River Plume Front: Winyah Bay, Sc, Usa, Christopher Papageorgiou, George Voulgaris, Alexander E. Yankovsky, Diane Bennett Fribance

Faculty Publications

This study presents Eulerian data from Winyah Bay, SC, USA collected during the passage of a tidal plume. The data captured the evolution and structure of the plume and include high-resolution velocity and temperature time series, supplemented by temperature – salinity profiles from a MicroCTD profiler. The observations identified a pre-existing plume extending to 4 m, with a water density of 1023.6 kg m−3, laying above denser ambient waters. Upon arrival, the newly discharged tidal plume introduced a fresher layer (1020.7 kg m−3) extending to 2.6 m, gradually thinning due to radial spreading. The plume's frontal …


Constraining Deviations From The Kerr Metric Via A Bumpy Parametrization And Particle Swarm Optimization In Extreme Mass-Ratio Inspirals, Xiaobo Zou, Xingyu Zhong, Wen-Biao Han, Soumya D. Mohanty Oct 2025

Constraining Deviations From The Kerr Metric Via A Bumpy Parametrization And Particle Swarm Optimization In Extreme Mass-Ratio Inspirals, Xiaobo Zou, Xingyu Zhong, Wen-Biao Han, Soumya D. Mohanty

Physics & Astronomy Faculty Publications

The measurement of deviations in the Kerr metric using gravitational-wave observations will provide a clear signal of new physics. Previous studies have developed multiple parametrizations (e.g., “bumpy” spacetime) to characterize such deviations in extreme mass-ratio inspirals (EMRIs). These approaches often rely on the Fisher information matrix (FIM) formalism to quantify the constraining power of future space-borne gravitational-wave detectors, such as LISA and Tianqin. For instance, using the analytical kludge waveform model under varying source configurations, such methods have achieved constraint sensitivity levels ranging from 10−4 to 10−2 on the dimensionless bumpy parameter 𝛿⁢˜𝑄 for LISA. In this paper, we advance …


Computational Nanoscale Investigations Of Structure, Dynamics, And Reactivity At Solid–Liquid Interfaces, Golam Azom Oct 2025

Computational Nanoscale Investigations Of Structure, Dynamics, And Reactivity At Solid–Liquid Interfaces, Golam Azom

LSU Doctoral Dissertations

Interfaces where two or more condensed phases meet govern phenomena central to catalysis, electrochemical energy conversion, separations, and environmental remediation. Their structural heterogeneity and dynamic nature make them challenging to probe experimentally, but computer simulations provide molecular-level insights into processes that remain inaccessible to experiments. This dissertation employs ab initio molecular dynamics (AIMD), classical molecular dynamics, and machine-learned interatomic potentials to investigate the structure, dynamics, and proton transport at graphene oxide (GO)–liquid interfaces.

The first project explores aqueous GO interfaces across a spectrum of oxidation states that extends from highly oxidized sheets to fully reduced graphene. Deep neural network force …


Existence, Uniqueness, Stability And Exact Expression Of Periodic Traveling Wave Solutions Of The Higher-Order Cubic-Quintic Nonlinear Schrödinger Equation, Nan Wang, Yuqian Zhou, Zhijun Qiao Oct 2025

Existence, Uniqueness, Stability And Exact Expression Of Periodic Traveling Wave Solutions Of The Higher-Order Cubic-Quintic Nonlinear Schrödinger Equation, Nan Wang, Yuqian Zhou, Zhijun Qiao

School of Mathematical & Statistical Sciences Faculty Publications

In this paper, the high-order cubic-quintic nonlinear Schrödinger equation is considered. By overcoming the difficulties caused by its non-integrability, we completely explore the existence, uniqueness and stability of the limit cycle of the equation. It enables us to accurately give the explicit parameter representation of its periodic wave solution in a special form for the first time. These results provide not only a new idea of obtaining periodic solutions in complex nonlinear systems, but also the important theoretical support for understanding related wave phenomena.


Flow Structure And Mixing Near A Small River Plume Front: Winyah Bay, Sc, Usa, Christopher Papageorgiou, George Voulgaris, Alexander E. Yankovsky, Diane Bennett Fribance Oct 2025

Flow Structure And Mixing Near A Small River Plume Front: Winyah Bay, Sc, Usa, Christopher Papageorgiou, George Voulgaris, Alexander E. Yankovsky, Diane Bennett Fribance

Faculty Publications

This study presents Eulerian data from Winyah Bay, SC, USA collected during the passage of a tidal plume. The data captured the evolution and structure of the plume and include high-resolution velocity and temperature time series, supplemented by temperature – salinity profiles from a MicroCTD profiler. The observations identified a pre-existing plume extending to 4 m, with a water density of 1023.6 kg m−3, laying above denser ambient waters. Upon arrival, the newly discharged tidal plume introduced a fresher layer (1020.7 kg m−3) extending to 2.6 m, gradually thinning due to radial spreading. The plume's frontal …


Applying Machine Learning Methods To Laser Acceleration Of Protons: Synthetic Data For Exploring The High Repetition Rate Regime, John J. Felice, Ronak Desai, Nathaniel Tamminga, Joseph R. Smith, Alona Kryshchenko, Christopher M. Orban, Michael L. Dexter, Anil K. Patnaik Oct 2025

Applying Machine Learning Methods To Laser Acceleration Of Protons: Synthetic Data For Exploring The High Repetition Rate Regime, John J. Felice, Ronak Desai, Nathaniel Tamminga, Joseph R. Smith, Alona Kryshchenko, Christopher M. Orban, Michael L. Dexter, Anil K. Patnaik

Faculty Publications

Advances in ultra‐intense laser technology have increased repetition rates and average power for chirped‐pulse laser systems, which offer a promising solution for many applications including energetic proton sources. An important challenge is the need to optimize and control the proton source by varying some of the many degrees of freedom inherent to the laser‐plasma interactions. Machine learning can play an important role in this task, as our work examines. Building on our earlier work in Desai et al. 2024, we generate a large ∼1.5 million data point synthetic data set for proton acceleration using a physics‐informed analytic model that we …


Effects Of Hydrological Connectivity On Created Marsh Sustainability, Katie Swann Oct 2025

Effects Of Hydrological Connectivity On Created Marsh Sustainability, Katie Swann

LSU Master's Theses

While efforts are being made to curb the high rate of coastal land loss in Louisiana, and even to restore ecosystem services and functions, it is generally accepted that restoration of these areas and functions is not a one-to-one value. It may take decadal time scales to reach efficient functional processing of nutrients and carbon storage rates, which may never reach true capacity comparable to similar naturally-organized systems. Although it is imperative to preserve these areas, restoration of ecosystem services and biogeochemical processes of coastal wetlands are preferable to future without action scenarios. Effectively directing the use of the limited …


Rewilding The Built Environment: Navigating Economic, Political, And Social Barriers To Urban Ecological Restoration, Carly E. Smith Oct 2025

Rewilding The Built Environment: Navigating Economic, Political, And Social Barriers To Urban Ecological Restoration, Carly E. Smith

PANDION: The Osprey Journal of Research and Ideas

Urban rewilding offers a nature-based approach to restoring ecological processes in cities while advancing climate resilience, biodiversity, and public well-being. Unlike conventional green infrastructure, rewilding allows ecosystems to develop with minimal intervention, emphasizing succession, complexity, and long-term adaptability. This paper examines the political, economic, and social factors that frame how rewilding is understood and implemented in urban planning. Governmental frameworks often prioritize order, predictability, and short-term results, making it difficult to accommodate the uncertainty and ecological complexity that rewilding requires. Economic models struggle to capture its long-term value, frequently overlooking ecosystem services or reconciling competing land uses. Social perceptions of …


Enhancing Llm Code Generation: A Systematic Evaluation Of Multi-Agent Collaboration And Runtime Debugging For Improved Accuracy, Reliability, And Latency, Nazmus Ashrafi Oct 2025

Enhancing Llm Code Generation: A Systematic Evaluation Of Multi-Agent Collaboration And Runtime Debugging For Improved Accuracy, Reliability, And Latency, Nazmus Ashrafi

Thesis/ Dissertation Defenses

The use of large language models (LLMs) for automated code generation has emerged as a significant focus within AI research. As these pretrained models continue to evolve, their ability to understand and generate complex code structures has opened up new possibilities for automating intricate programming tasks with greater accuracy. Although contemporary foundational models demonstrate promising results, researchers continue to explore optimal post-training strategies to enhance code quality. These include supervised fine-tuning, retrieval-augmented generation (RAG), debugging, and many others. In this thesis, I combine two such widely used post training approaches—namely (1) multi-agent collaboration and (2) runtime execution of information-based debugging—for …


Enzymes Of Calendula Officinalis L. As Affected By Foliar Application Of Nano-Nitrogen And Potassium Fertilizers, Under Water Stress Conditions, Aqeel Abdulabbas Alsudani, Qais Hussain Abbas Al-Semmak Oct 2025

Enzymes Of Calendula Officinalis L. As Affected By Foliar Application Of Nano-Nitrogen And Potassium Fertilizers, Under Water Stress Conditions, Aqeel Abdulabbas Alsudani, Qais Hussain Abbas Al-Semmak

Karbala International Journal of Modern Science

Water stress is a major environmental factor that limits the growth and productivity of Calendula officinalis L. To alleviate its negative effects, recent approaches have increasingly focused on nano-fertilizers that enhance plant antioxidant defenses. This study therefore aimed to evaluate the effect of foliar application of nano-nitrogen (0, 2, and 4 mL L⁻¹) and nano-potassium (0, 2, and 4 g L⁻¹) fertilizers under two irrigation regimes (100% and 50% of field capacity) on the activity of key antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD). The results revealed that irrigation at 50% field capacity significantly increased CAT, …


Attention Mapping For Hallucination Reduction In Arabic Financial Using Retrieval-Augmented Generation Systems, Hasan Abdulameer Hasan, Khaldoun H. Al-Hussayni, Ali Z. K. Matloob Oct 2025

Attention Mapping For Hallucination Reduction In Arabic Financial Using Retrieval-Augmented Generation Systems, Hasan Abdulameer Hasan, Khaldoun H. Al-Hussayni, Ali Z. K. Matloob

Journal of Intelligent Informatics, Networking, and Cybersecurity

This research introduces a customized attention visualization framework for mitigating hallucinations in Arabic Retrieval-Augmented Generation (RAG) systems tailored for financial document analysis. The proposed architecture extends MarBERT with a dual-stage attention supervision mechanism and a hallucination-aware loss formulation, trained on a newly constructed dataset of 7,000 annotated Arabic financial query-context pairs. A grounding alignment score is computed over attended tokens, and generated responses are rejected when falling below a dynamically adjusted precision-aware threshold,serving as the core decision-making approach for hallucination detection. The system achieves 95.04% classification accuracy, 95.84% precision, 94.12% recall, and an F1 score of 94.97%, outperforming AraELECTRA and …


Italian Mathematics Prison Teachers’ Perspective On The Teaching/Learning Of Mathematics In Prison School, Andrea Maffia, Luca Decembrotto, Chiara Giberti, Federica Mennuni, Gabriella Pocalana, Silvia Regola, Agnese Telloni Oct 2025

Italian Mathematics Prison Teachers’ Perspective On The Teaching/Learning Of Mathematics In Prison School, Andrea Maffia, Luca Decembrotto, Chiara Giberti, Federica Mennuni, Gabriella Pocalana, Silvia Regola, Agnese Telloni

Journal of Prison Education Research

Teaching in the prison context is characterized by a high complexity level; it is a multifaced activity influenced by several factors depending on the specific context. We present a preliminary but overall picture of schooling in Italian prisons by considering teachers’ reflections regarding their experiences in teaching mathematics in correctional facilities. To address the gap in the current literature on this issue, we conducted a SWOT analysis on the reflection provided by a group of nine Italian mathematics teachers who teach in different prisons and with different experiences and backgrounds. Their reflection allowed us to identify and describe six theory-driven …


Re: Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Butte Treatment Lagoons (Btl) Groundwater Treatment System Routine Operations, Maintenance, And Monitoring (Om&M) Plan (Dated August 29, 2025), Emma Rott Oct 2025

Re: Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) Butte Treatment Lagoons (Btl) Groundwater Treatment System Routine Operations, Maintenance, And Monitoring (Om&M) Plan (Dated August 29, 2025), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Re: Conditional Approval Letter For The Butte Priority Soils Operable Unit Clark Tailings Consolidated Waste Management Area Site Investigation Quality Assurance Project Plan Revision 0 (2025 Update) And Response To Epa Comments. (Dated September 16, 2025), Emma Rott Oct 2025

Re: Conditional Approval Letter For The Butte Priority Soils Operable Unit Clark Tailings Consolidated Waste Management Area Site Investigation Quality Assurance Project Plan Revision 0 (2025 Update) And Response To Epa Comments. (Dated September 16, 2025), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


A Guide To Breaking Seed Dormancy Of Common Wetland Plant Species, Samantha R. Kurkowski, Rae Robinson, Sandra E. Johnston, Montana M. Horchler, Adrienne E. Ernst, Margaret D. Haney, Karin M. Kettenring Oct 2025

A Guide To Breaking Seed Dormancy Of Common Wetland Plant Species, Samantha R. Kurkowski, Rae Robinson, Sandra E. Johnston, Montana M. Horchler, Adrienne E. Ernst, Margaret D. Haney, Karin M. Kettenring

All Current Publications

This guide was developed from a series of seed dormancy break and germination experiments conducted over 4 years with 41 species. The purpose of this guide is to synthesize the information we learned through these experiments and present the findings for those interested in breaking seed dormancy, such as land managers, restoration practitioners, and wetland researchers. Ultimately, we hope this guidance catalyzes further wetland restoration throughout the Intermountain West.


Higher Education Cybersecurity: A Vulnerability Assessment Of The U.S. South’S Institutional Websites, Zachary W. Taylor, Vivi Vo Oct 2025

Higher Education Cybersecurity: A Vulnerability Assessment Of The U.S. South’S Institutional Websites, Zachary W. Taylor, Vivi Vo

Journal of Cybersecurity Education, Research and Practice

As technology continues to advance, it is critical to understand how higher education institutions protect digital information of their stakeholders including students, faculty, and staff through cybersecurity measures. Although conceptual research has articulated various aspects of cybersecurity, no empirical research has explored the cybersecurity of higher education (.edu) websites through a vulnerability scan of these websites via an open PortScan and analysis. To fill a critical gap in the literature, this study conducted a vulnerability scan and open PortScan and analysis of all higher education websites in three of the lowest-income states in the United States: Louisiana (n=112), Mississippi (n=52), …


Defect-Driven Degradation Of Mxenes In Aqueous Environments And Mitigation Strategies: Insights From First-Principles, Ana Maria Stratulat, Valentina Nesterova, Vladislav Korostelev, Majid Beidaghi, Vadym Mochalin, Konstantin Klyukin Oct 2025

Defect-Driven Degradation Of Mxenes In Aqueous Environments And Mitigation Strategies: Insights From First-Principles, Ana Maria Stratulat, Valentina Nesterova, Vladislav Korostelev, Majid Beidaghi, Vadym Mochalin, Konstantin Klyukin

Chemistry Faculty Research & Creative Works

MXenes have attracted considerable attention due to their tunable surface chemistry, high electrical conductivity, and ease of solution processing, making them promising candidates for a wide array of applications. The inherent tendency of MXenes to degrade under environmental conditions constrains their compositional diversity and limits certain practical applications. Our computational study shows that degradation of defect-free Ti3C2Txis kinetically limited, whereas common defects markedly lower the activation barriers for water attack. Using ab initio molecular dynamics simulations (AIMD) combined with thermodynamic analysis, we show that titanium vacancies VTiact as active sites for the protonation of subsurface carbon …


Investigating Characteristic Droplet Size Distributions In Large Eddy Simulations Of Stratocumulus Clouds, Nithin Allwayin, Daniel J. Miller, Kamal Kant Chandrakar, Michael L. Larsen, Raymond A. Shaw Oct 2025

Investigating Characteristic Droplet Size Distributions In Large Eddy Simulations Of Stratocumulus Clouds, Nithin Allwayin, Daniel J. Miller, Kamal Kant Chandrakar, Michael L. Larsen, Raymond A. Shaw

Michigan Tech Publications

Cloud processes relevant to radiative and precipitation properties depend on the shape of the cloud droplet size distribution. Recent holographic observations revealed that cloud droplet populations do not have the same size distribution shapes throughout but form regions of characteristic distributions with similar microphysical properties. We investigate the existence and properties of these characteristic distributions within Large-Eddy Simulations of stratocumulus clouds using Lagrangian and bin microphysics schemes. Distribution types are identified, revealing localized characteristic distributions that vary on the scale of the largest convective cell for simulations with bin microphysics. The results from the Lagrangian microphysics scheme hint at similar …


Reliable Detection Of Sf6breakdown Byproducts Using 2d Non-Hexagonal Carbon Allotrope Nanosheets, Pedro Elias Priori Spalenza, Fábio Arthur Leão De Souza, Debora C.M. Rodrigues, Rodrigo G. Amorim, Cesar E.P. Villegas, Wanderlã L. Scopel, Ravindra Pandey Oct 2025

Reliable Detection Of Sf6breakdown Byproducts Using 2d Non-Hexagonal Carbon Allotrope Nanosheets, Pedro Elias Priori Spalenza, Fábio Arthur Leão De Souza, Debora C.M. Rodrigues, Rodrigo G. Amorim, Cesar E.P. Villegas, Wanderlã L. Scopel, Ravindra Pandey

Michigan Tech Publications

Sulfur hexafluoride (SF6), widely used as an insulating gas in the power industry, decomposes during long-term operation into byproducts such as H2S, SO2, SO2F2, and SOF2. Reliable detection of these compounds is essential, since their type and concentration provide diagnostic signatures of faults in gas-insulated switchgear. We employ density functional theory combined with nonequilibrium Green’s function calculations to evaluate pristine two-dimensional carbon allotropes with nonhexagonal rings, namely Graphene+, T-graphene, and Biphenylene, as potential field-effect nanosensors. To characterize the surfaces’ atomic structures, we simulated scanning tunneling microscopy images for filled states. Each surface exhibits a distinct brightness pattern that allows its …


Fahp-Topsis Model In Ranking Critical Success Factors Of E-Learning: A Comparative Analysis Of Normalization Methods, Judith R. Pande, David Koloseni, Septimi Kitta Oct 2025

Fahp-Topsis Model In Ranking Critical Success Factors Of E-Learning: A Comparative Analysis Of Normalization Methods, Judith R. Pande, David Koloseni, Septimi Kitta

Tanzania Journal of Science

The teaching and learning process has become effective and explicit due to the progressive development of e-learning. This has significantly transformed the education framework. As a result, evaluating the usefulness of e-learning requires a detailed understanding of the critical success factors that impact the success of e-learning environments. This study ranked these factors using Multi-Criteria Decision-Making techniques. Specifically, the Fuzzy Analytical Hierarchy Process was used to determine the weight of each factor, while the Technique for Order of Preference by Similarity to Ideal Solution was used to rank the factors of e-learning. The study also examined and compared four normalization …


Assessment Of Tumour Control Probability And Equivalent Uniform Dose In Conventional 3d-Crt Vs. Hypo-Fractionated Imrt, Jumaa D. Kisukari, Mwingereza J. Kumwenda, Khamis O. Amour, Ehab M. Attalla, Emmanuel Lugina Oct 2025

Assessment Of Tumour Control Probability And Equivalent Uniform Dose In Conventional 3d-Crt Vs. Hypo-Fractionated Imrt, Jumaa D. Kisukari, Mwingereza J. Kumwenda, Khamis O. Amour, Ehab M. Attalla, Emmanuel Lugina

Tanzania Journal of Science

Hypo-fractionated (HF) radiotherapy offers a promising solution to improve access to cancer treatment in resource-limited settings, such as developing countries, by reducing the number of treatment sessions compared to conventional fractionation (CF). For effective implementation, evaluating Equivalent Uniform Dose (EUD) and Tumour Control Probability (TCP) is essential to ensure treatment efficacy across different radiotherapy techniques. This study compares treatment plans generated using Three-Dimensional Conformal Radiation Therapy with Conventional Fractionation (3D-CRT CF) and Intensity Modulated Radiation Therapy with Hypo-fractionation (IMRT HF) in patients with localized prostate cancer. A total of 50 patients were CT-simulated, and their images were imported into a …


A Comparative Study For Classical Machine Learning Models For Swahili Social Media Sentiment Analysis, Mahadia Tunga, Davis David Oct 2025

A Comparative Study For Classical Machine Learning Models For Swahili Social Media Sentiment Analysis, Mahadia Tunga, Davis David

Tanzania Journal of Science

Despite sentiment analysis being one of the most popular applications in Natural Language Processing (NLP), most studies are skewed towards languages with a rich corpus (language database). Less emphasis has been placed on low-resource languages like Swahili. Swahili is the official language of the African Union and of 4 countries in East Africa, and is spoken by many people on the African continent. This study performed sentiment analysis using 3,000 tweets hosted on the Zindi Africa platform. Data was processed using a term frequency-inverse document frequency vectorization method, and five classical machine learning algorithms (RandomForest, XgBoost, and CatBoost, HistogramGradientBoost, LightGradientBoos) …


Evaluating Weather Research And Forecasting Model In Simulating March-May Rainfall In Tanzania: Implications Of Selecting Parameterization Schemes, Mohamed H. Mohamed, Makungu James Ng'oga Oct 2025

Evaluating Weather Research And Forecasting Model In Simulating March-May Rainfall In Tanzania: Implications Of Selecting Parameterization Schemes, Mohamed H. Mohamed, Makungu James Ng'oga

Tanzania Journal of Science

The current study evaluates the performance of the Weather Research and Forecasting (WRF) model in simulating seasonal rains of March-May (MAM) in Tanzania, based on the implication of selecting parameterization scheme combinations. The model was configured into two domains with horizontal resolutions of 36 km and 12 km and the initial and lateral boundary conditions were provided by the Climate Forecast System Version 2 at 00 UTC. However, only the inner domain of 12 km was used for analysis, which has a fine horizontal resolution that accounts for small scale features such as terrains. Twelve simulations have been performed using …


Mathematical Analysis Of Toxicants And Diseases Impact On A Prey-Predator System With Control Interventions, Nuru Yazidi Juma, Thadei Damas Sagamiko, James Philbert Mpele Oct 2025

Mathematical Analysis Of Toxicants And Diseases Impact On A Prey-Predator System With Control Interventions, Nuru Yazidi Juma, Thadei Damas Sagamiko, James Philbert Mpele

Tanzania Journal of Science

This study developed a generic prey-predator mathematical model incorporating logistic growth for prey and a Holling Type I functional response for predator consumption. Prey-predator interactions form the foundation of ecological balance, but in recent decades these systems have been increasingly threatened by toxicants and infectious diseases. The combined effect of these challenges can lead to severe population declines, biodiversity loss, and ecosystem instability, making their study important for conservation and environmental management. The model includes the effects of diseases and toxicants on prey and toxicants only on predators, and explores optimal control strategies to mitigate these threats. Without considering time …


Design Of High-Performance Synchronous Reluctance Motor For Hybrid Electric Vehicle Application, Fred Loita, Jackson Justo Oct 2025

Design Of High-Performance Synchronous Reluctance Motor For Hybrid Electric Vehicle Application, Fred Loita, Jackson Justo

Tanzania Journal of Science

This paper presents the simulation-based design of a synchronous reluctance motor (SynRM) coupled electromechanical system suitable for the hybrid electric vehicle. The study considers SynRM with a 75kW power rating with the capability to produce up to 125kW maximum power for the electric vehicle. The focus is mainly on rotor and stator design; the angles of the flux-barrier ends are considered to reduce the torque ripple due to the slot harmonics. Reluctance machines are indeed competitive for applications requiring high efficiency at low cost. However, it is a challenging task to find design solutions that ensure structural integrity of the …


Rainwater Harvesting For Domestic Use In Suburb Areas Of Dar Es Salaam, Tanzania: A Case Study Of Wazo Hill, Scholastica S. Ishengoma, Mahir Mohammed Said, Neema O. Msuya Oct 2025

Rainwater Harvesting For Domestic Use In Suburb Areas Of Dar Es Salaam, Tanzania: A Case Study Of Wazo Hill, Scholastica S. Ishengoma, Mahir Mohammed Said, Neema O. Msuya

Tanzania Journal of Science

Despite the increasing reliance of rainwater harvesting in semi-urban areas, there is a lack of comprehensive localized data on the safety of harvested rainwater, particularly in areas such as Wazo Hill where communities predominantly depend on it. This study evaluates the quality of harvested rooftop rainwater intended for human consumption and assesses its compliance with the World health Organization (WHO) and Draft East Africa Standards (DEAS) for drinking water. Rainwater samples were collected from various catchment surfaces and storage systems located in Wazo Hill, Tanzania. A stratified random sampling technique was employed to select the households equipped with rainwater harvesting …


Assessment Of Bacteriological Quality And Physico-Chemical Parameters Of Domestic Water Sources In Relation To Human Health Risk In Kigamboni, Tanzania, Joseph A. Mwakosya Oct 2025

Assessment Of Bacteriological Quality And Physico-Chemical Parameters Of Domestic Water Sources In Relation To Human Health Risk In Kigamboni, Tanzania, Joseph A. Mwakosya

Tanzania Journal of Science

Data on bacteriological quality and physico-chemical parameters is crucial for protection and sustainable utilization of water resources. This study determined bacteriological quality and physico-chemical parameters of well and tap water sourcesin relation to human health risk in Kigamboni, Tanzania. Thirty water samples were collected randomly and analyzed using SPSS software. The mean values for well water samples of pH, electrical conductivity (EC), total dissolved solids (TDS), turbidity, Chloride, Sulphate, Nitrate, Phosphate, and Calcium Carbonate were 7.2, 960.27 mg/L, 528.13 mg/L, 1.52 NTU, 288.00 mg/L, 30.13 mg/L, 0.05 mg/L, 0.08 mg/L, and 160.07 mg/L, respectively. The mean values for tap water …


Comparative Study On The Application Of Gra, Psi And Hybrid Psi-Gra Techniques For Optimising Turning Parameters In Multi-Criteria Problems, Mussa Iddi Mgwatu Oct 2025

Comparative Study On The Application Of Gra, Psi And Hybrid Psi-Gra Techniques For Optimising Turning Parameters In Multi-Criteria Problems, Mussa Iddi Mgwatu

Tanzania Journal of Science

The optimum turning parameters help to justify the investment in machine tools for manufacturing industries. However, solving optimisation models to achieve optimum turning parameters in multi-criteria environment is complex leading to the application of multi-criteria decision-making techniques. This paper compares three multi-criteria decision-making techniques in determining optimum turning process parameters namely spindle speed, feed rate and depth of cut. The performance criteria are material removal rate, consumed electrical energy and tool wear rate. Example data for turning process were obtained from other studies while the analyses for multi-criteria decision-making were performed using grey relational analysis (GRA), preference selection index (PSI) …


Heavy Metal Contamination And Health Risks In Katoro's Artisanal Gold Mining Soils, Tanzania, Innocent J. Lugendo, Venance Mwesiga Oct 2025

Heavy Metal Contamination And Health Risks In Katoro's Artisanal Gold Mining Soils, Tanzania, Innocent J. Lugendo, Venance Mwesiga

Tanzania Journal of Science

This study assessed heavy metal contamination in surface soils from artisanal gold mining areas in Katoro, Tanzania, evaluating ecological and human health risks. Thirty-six soil samples were systematically collected from three mining villages (Bingwa, Isenye, and CCM) at varying distances ranging from 30 to 90 m from active mining pits alongside twelve control samples from a non-mining area for comparison purposes. Concentrations of Cr, Cu, Ni, Zn, Pb, and As in soil samples were analyzed using energy-dispersive X-ray fluorescence spectrometry (EDXRF). Results revealed severe contamination, with Cr (117–1255 mg/kg), Cu (81–104 mg/kg), and Ni (89–271 mg/kg) exceeding permissible limits. The …