http://ir.mu.ac.ke:8080/jspui/handle/123456789/65 2026-08-25T11:14:35Z http://ir.mu.ac.ke:8080/jspui/handle/123456789/10447 Title: Analyzing incoherence and inconsistencies in data utilization within maintenance operations for critical equipment in the weaving section of textile manufacturing processes Authors: Bett, Kipchumba; Chemweno, Peter; Nganyi, Eric; Ochola, Jerry Abstract: In the context of textile manufacturing’s weaving section, efficient maintenance operations play a pivotal role in upholding critical equipment’s peak performance and longevity. However, inconsistencies in data utilization during maintenance can lead to equipment failures, downtimes, and decreased efficiency. To address this, this study endeavors to scrutinize these data dis parities, focusing on the weaving section’s essential machinery. The objective encompasses identifying failure patterns, gauging parameter impacts on system components, and proposing personalized maintenance strategies based on failure characteris tics. The study employed the Weibull distribution plot to analyze data from 19 distinctive components, with shape (β) and scale (η) parameters elucidating failure trends, distinguishing early-life and wear-out failures. The Anderson-Darling (AD) statistic validated Weibull fitting. Visual aids and charts presented findings effectively. Analysis showcased distinct failure patterns across system components, where shape parameters exceeding 1 denoted wear-out failures, and scale parameters re vealed equipment lifespans. The study emphasized the necessity of bespoke maintenance approaches in response to equipment failure traits. Tailoring strategies for early-life and wear-out failures is essential. The Weibull analysis aids in pinpointing crucial maintenance junctures, optimizing schedules, and enhancing equipment reliability. This study’s contribution lies in ele vating equipment dependability, curbing downtimes, and augmenting operational efficiency in textile manufacturing processes. Recommendations encompass tailored maintenance strategies, prioritized preventive measures for wear-out-prone components, comprehensive craftsman training, and exploring predictive techniques leveraging sensor data and AI. 2023-08-01T00:00:00Z http://ir.mu.ac.ke:8080/jspui/handle/123456789/10445 Title: Mechanical and durability properties of concrete with limestone calcined clay cement: assessing the suitability of Tanzanian kaolinite clay Authors: Okumu, Victoria Akoth; Shitote, Stanley Muse; Koteng, David Otieno; Myamba, Yohakimu Jinifa Abstract: In most African countries, supplementary cementitious materials (SCMs), such as silica fume, slag, and fly ash, are scarce, creating a need for alternative low-clinker cement that utilises locally abundant resources. Given the limited availability of SCMs, the development of Limestone Calcined Clay Cement (LC3) has emerged as an attractive solution. LC3 is a blended binder composed of ground limestone, calcined kaolinite clay, and ordinary Portland cement clinker. This research assessed the mechanical and durability properties of LC3 binders formulated using raw materials obtained from selected deposits in Tanzania. Two samples of clay from the Pugu deposit were selected: Pugu hard clay (PH) and Pugu soft clay (PS). Limestone and gypsum were sourced from Dar es Salaam. LC3 mixes containing 58% CEM I/42.5N were produced and used to make concrete with a water/binder ratio of 0.4. Two control mixes were made, a mix with 100% Portland cement CEM I/42.5 N and a mix with 100% Portland pozzolana CEM II/P-B 42.5 N. In addition, four concrete mixes were designed for the study: LC3-PH, LC3-PS, CEM I + PH (CC-PH), and CEM I + PS (CC-PS). The mechanical properties evaluated included compressive strength, splitting tensile strength, and flexural strength, whilst durability performance was assessed through sulfuric acid resistance, water sorptivity, and absorption. The results demonstrated the superiority of LC3 concrete compared to CEM I and CEM II concretes. For instance, the LC3-PS mix achieved a 90-day compressive strength of 63 ± 2.1 MPa, compared with 62 ± 1.8 MPa for CEM I. Similarly, water absorption was 1.35% and 1.1% for CEM I and LC3 concretes, respectively. Under sulfuric acid exposure, LC3 concrete exhibited the lowest mass loss (1.6%) and strength loss (17.9%) compared with 2.4% and 23% for CEM I and 2.1% and 21% for CEM II, respectively. The enhanced performance of LC3 concrete was attributed to its denser and more refined microstructure, which reduced pore connectivity and improved resistance to the ingress of aggressive agents. 2026-08-01T00:00:00Z http://ir.mu.ac.ke:8080/jspui/handle/123456789/10444 Title: Protection challenges of PV Integration in the Cameroon southern interconnected power network Authors: Nshizirungu, Albin; Talai, Stephen M; Letting, Lawrence K.; Belindah, Musavy Abstract: Integrating photovoltaic energy into existing electricity grids has become a common practice in the recent decades. However, this interconnection must be carefully planned in order to avoid their adverse impacts on the network operations. The aim of this study was to investigate the impacts photovoltaic (PV) integration may have on the protection of the Southern Interconnected Network (SIN) of Cameroon. In first time generalized fault study simulations were conducted for both three and single-phase faults. Battery energy storage systems (BESS) were added to each of three PV plants connected to the network, and then monitors were used to identify contribution of each component to the network fault currents. Impacts of PV on fuse, relay, and recloser operations were also assessed. Simulation results showed both decreases and increases in fault currents at different buses during generalized faults studies, but the differences were more severe with the single line to ground faults. The above findings are useful when calculating protective devices ratings in case of PV integration. Contributions of 683.694 A and 259.498 A from both the PV plant and the BESS at B15NGOUS1 bus respectively were recorded. There were also contributions of 42.274 A and 23.428 A to the fault currents from PV plants at B15BASS21 and B10ALU buses respectively while their corresponding BESSs rather take 10.289 A and 6.448 A in that order. The simulations result also showed that PV integration increases the fault critical clearing time by 0.444 seconds and 13.728 seconds for fuse and relay respectively, while there was no impact on fault clearing time in the case of recloser. From the findings it is obvious that PV integration into the SIN may affect the network protection arrangements by changing both fault currents and clearing time. Therefore, it is highly recommended to consider protection upgrades especially fuses and relays when planning PV integration into existing grids in general and into the SIN particularly. 2025-10-01T00:00:00Z http://ir.mu.ac.ke:8080/jspui/handle/123456789/10440 Title: Advances in biogas desulfurization using organic and inorganicsorbents: A review Authors: Mecha, Cleophas Achisa; Mrosso, Register Abstract: Access to clean and affordable energy is a key enabler of development. Biogas is anessential renewable and sustainable energy that has great potential in meetingenergy requirements, especially in areas with limited access to the grid. However, thepresence of impurities such as hydrogen sulfide limits its application by corrodingequipment parts and reducing the calorific value. Biogas desulfurization is thereforeimportant; however, there are limited studies available. The current study criticallyevaluated existing biogas sweetening technologies applied on an industrial scale inthree main categories: pre-digestion, during digestion, and post-digestion. Theremoval of H 2S using sorption processes employing a variety of organic and inorganicsorbents was comprehensively reviewed. The effectiveness of inorganic materialssuch as red rock, ash, and zero-valent iron as well as organic sorbents including sweetpotato leaves, organic solvents, and water hyacinth was assessed. The effect of pro-cess conditions such as pH and moisture content especially for organic sorbents wasevaluated. The study proposed new ways of increasing the performance of the sor-bent materials through functionalization, recovery, regeneration, and reuse as well asbiogas pre-treatment to remove moisture. While most studies previously reportedfocused on H 2S during removal post-digestion, the current study evaluated the entireprocess train from pre-digestion, during digestion, and post digestion thereby provid-ing a more concise approach to biogas desulfurization. 2026-08-01T00:00:00Z