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Mbeya University of Science and Technology Repository (MUST Repository) is an open-access digital platform dedicated to the collection, preservation, management, and dissemination of the University’s official scholarly and institutional resources. Authorized by the University and aligned with national academic and research objectives, the repository ensures that valuable institutional knowledge remains securely preserved and easily accessible to researchers, students, staff, and the wider public.
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Multivariate analysis of land use/land cover (LULC) effects on water quality in the Lower Mara River catchment
(IWA Publishing, 2026-03-27) Alphayo, Stephano. M; Katambara, Zacharia; Swilla, Livingstone
The Lower Mara River catchment is increasingly subjected to anthropogenic pressure due to land-use/land-cover (LULC) changes, which significantly influence river water quality. This study assessed the effects of LULC on water quality in the Lower Mara River catchment. Water samples were collected from 12 sampling stations during February, August, and December 2025 and analysed for nine physicochemical and biological parameters. Land use/land cover classification was conducted using satellite imagery and GIS techniques, while Pearson correlation and Redundancy Analysis (RDA) were used to evaluate relationships between LULC and water quality parameters within 500, 1,000 and 1,500 m river buffer zones. The results showed that grassland was the dominant land cover type (63.63%), followed by cropland (17.76%) and forest (11.42%). Turbidity, biochemical oxygen demand (BOD5) and faecal coliform concentrations exceeded Tanzania’s standards at several sampling locations, indicating water quality degradation. Pearson correlation and RDA revealed that cropland and built-up areas were significantly positively associated (p < 0.01) with turbidity, nutrients, BOD5, and faecal coliforms, while forests, wetlands, and grasslands contributed to improved water quality conditions. The strongest LULC influence occurred within the 500 m riparian buffer zone. The study emphasises the significance of sustainable management and protection of the river ecosystems.
Spatial Inertia-Aware Generation Scheduling Optimization Framework with Maximized Inertia-Less VRES Generation Dispatch for Grid Frequency Stability.
(Pan African University, 2026-05-02) Swetala, Emmanuel. G
The global transition toward low-carbon power systems has accelerated the integra-tion of variable renewable energy sources (VRES). While this transition contributes to carbon-emission reduction, it also displaces synchronous generators (SGs) that inherently provide rotational inertia. The resulting decline in system inertia, to-gether with its non-uniform spatial redistribution across the network, can alter frequency dynamics and increase the risk of local frequency instability following disturbances. Conventional operational and planning approaches commonly rely on aggregated system-level inertia metrics, which may obscure locational vulner- abilities and fail to reveal bus-level violations of frequency stability limits even when global indices appear secure.
This thesis proposes and validates a spatially resolved framework for inertia estima- tion and inertia-aware generation scheduling in power systems with high penetration of inertia-less VRES. First, an offline method for estimating bus-level inertia dis- tribution is developed. The method uses steady-state network parameters to quantify the effective inertia reflected at individual buses within the power network.This formulation provides a transparent mapping of spatial inertia distribution without requiring online measurements, time-domain simulations, or disturbance data during the estimation stage, making it suitable for planning and operational studies. Building on this foundation, a multi-objective optimization framework is formulated to maximize inertia-less VRES penetration while maintaining frequency stability. The framework enforces minimum inertia thresholds at each bus, rather than relying solely on aggregated system inertia constraints. Transmission losses and synchronous generator commitment are simultaneously considered using the Non-Dominated Sorting Genetic Algorithm II. The resulting Pareto front reveals trade-offs between VRES penetration, network efficiency, and inertia adequacy,v and identifies operating points that balance these competing objectives. The proposed methods are evaluated on modified IEEE 9- and 39-bus benchmark systems. Results show that, with a bus RoCoF limit of 1 Hz/s, the selected Pareto knee operating point achieves 75% penetration of inertia-less VRES while reducing transmission losses by approximately 56%. Sensitivity analysis performed for RoCoF limits of 1 Hz/s, 2 Hz/s, and 3 Hz/s shows that stricter frequency stability requirements require higher synchronous inertia and consequently limit renewable penetration. Under the 1 Hz/s limit, the maximum achievable inertia- less VRES penetration is approximately 82% with the lowest transmission losses due to reduced line loading. Relaxing the limit to 2 Hz/s increases the achievable penetration to about 86%, while the most relaxed limit of 3 Hz/s permits up to 95% VRES penetration but results in higher transmission losses due to increased line loading. The analytical inertia formulation is benchmarked against kinetic- energy-based frequency stability indicators and time-domain dynamic simulations, showing strong agreement in RoCoF and frequency nadir estimates. In addition, stochastic simulations under time-varying load and VRES conditions indicate that the proposed inertia-aware scheduling framework improves both the average performance and variability of key frequency stability indices relative to the benchmark method. Overall, this thesis extends existing inertia estimation and inertia-constrained scheduling approaches by linking bus-level spatial inertia assessment with multi- objective VRES-aware generation scheduling. The proposed framework provides a planning-oriented approach for identifying frequency-security limits, inertia bottle- necks, and feasible renewable dispatch levels in low-inertia power systems. The findings support the use of spatially informed inertia management as a complemen- tary tool for maintaining frequency stability in future power systems with high levels of converter-interfaced renewable generation.
Mathematical modeling and optimization of monocyte-driven immune dynamics and treatment strategies in within-host Mycobacterium tuberculosis
(MATHEMATICS IN MEDICAL AND LIFE SCIENCES, 2026-03-23) Helikumi , Mlyashimbi; Mushayabasa, Steady
Tuberculosis (TB) remains a major global health challenge, driven by complex within-host interactions between Mycobacterium tuberculosis (Mtb) and the host immune system. To better understand these dynamics, we develop a mathematical model that incorporates monocytes, macrophages, and T lymphocytes. Analytical results show that the basic repro- duction number, R0, depends on key infection and immune-response parameters and can exceed unity under biologically plausible conditions, leading to persistent infection. Bifur- cation analysis reveals the occurrence of a backward bifurcation at R0 = 1, indicating that reducing R0 below unity may not be sufficient for disease eradication, as stable endemic equilibria can coexist with the disease-free equilibrium when R0 < 1. Numerical simu- lations under baseline parameter values demonstrate that enhancing immune response parameters substantially lowers bacterial burden, reducing bacterial populations by up to 70% within 60 days, whereas increased infection rates accelerate disease progression, doubling bacterial populations in approximately half the time. Furthermore, an optimal control analysis suggests that, under representative treatment scenarios, intensified drug treatment can reduce bacterial loads by more than 90% within 30 days; however, com- plete bacterial clearance may remain unattainable because of the backward bifurcation phenomenon. These findings underscore the importance of integrating immune enhance- ment with optimized treatment strategies and highlight that achieving R0 < 1 alone may not guarantee eradication of TB infection.
Comparative Evaluation of the TANROADS Road Maintenance Management System (RMMS) against MCDA Practice: Systematic Review - A Case of Tanzania
(private, 2026-09-16) Eliesikia S. Mrutu,; Tekka, Ramadhan; Mwishwa, Yazid
The RMMS employed by TANROADS provides a structured, multi-criteria analysis (MCA) framework for prioritizing maintenance interventions on trunk and regional roads. This study reviewed the literature to assess RMMS effectiveness against international MCDA practice, identify implementation barriers, and propose optimisations amid constrained resources and climate vulnerabilities. A PRISMA-guided systematic literature review searched academic databases and journals, using targeted keywords related to RMMS, MCA in road maintenance, and challenges in Tanzania and comparable contexts. About 60 peer- reviewed articles and reports were retained after screening for relevance, yielding an inductive content analysis of RMMS decision-making, priority logic, success factors, barriers, and international comparisons. The reviewed literature indicates RMMS is best suited to high-traffic corridors, with documented limitations on regional roads, including persistent traffic-centric bias, inadequate integration of climate vulnerabilities, insufficient GIS modelling, institutional capacity constraints, partial funding disbursements, and poor adaptability of MCA weights and HDM- 4 models. Comparative analysis with MCDA systems in Indonesia (AHP-GIS for spatial), Australia (optimised hybrids for climate resilience), the United States (LCA-integrated equity), and Nigeria/South Africa (rural-focused GIS-MCDA) highlights RMMS as less equitable and climate-responsive. Recommendations include recalibrating MCA weights to enhance rural equity and climate resilience, adopting digital tools and GIS for improved data quality, implementing targeted training and capacity building, securing full funding alignment, and piloting hybrid models such as fuzzy-AHP. These enhancements could foster more proactive and sustainable maintenance priorities across Tanzania's regional network.
Distribution patterns and conservation status of anurans in Kanga forest reserve, Eastern Arc Mountains, Tanzania
(Universuty of LATVIA, 2026-06-22) Mugini, Geofrey; Ojija, Fredrick; Ojija, Fredrick
Understanding the ecological drivers of anuran assemblages is essential for biodiversity conservation in tropical montane ecosystems. This study assessed anuran diversity, distribution patterns, conservation status, and environmental determinants of species in Kanga Forest Reserve (KFR), an important component of the Eastern Arc Mountain Forests of Tanzania. Standardized surveys were conducted across four elevational categories and major habitat types to evaluate how habitat structure and environmental conditions influence anuran communities. A total of 455 individuals representing 22 species, 12 genera, and seven families were recorded. Species abundances were highest in lowland and sub-montane forests, whereas farmland and montane forests had fewer individuals. Similarly, diversity was highest in lowlands (H’ = 2.45) and lowest in farmland (H’ = 1.80), indicating anthropogenic impacts. Forest-restricted taxa, including Callulina kanga and Probreviceps cf. durirostris, were largely confined to structurally intact forest habitats, whereas species such as Chiromantis rufescens and Ptychadena anchietae exhibited broader ecological tolerances. Integrated analyses revealed that anuran distributions were influenced primarily by hydrological conditions and forest structural complexity. Water bodies, canopy cover, tree density, leaf litter, and mature trees emerged as the strongest predictor of species occurrence, closely associated with species persistence and community composition. The results therefore demonstrate that habitat complexity and moisture availability function as key ecological filters shaping community assembly within KFR. Conservation assessment revealed species spanning multiple IUCN Red List categories, including Critically Endangered, Endangered, Vulnerable, and Near Threatened taxa, highlighting the reserve’s importance as a refuge for threatened anurans. This study provides a robust baseline for long-term monitoring and delivers testable ecological evidence to guide conservation planning, habitat restoration, and adaptive management within KFR and the broader Eastern Arc Mountain ecosystem.