http://repository.ou.ac.lk/handle/123456789/4270 Fri, 09 Oct 2026 17:05:48 GMT 2026-10-09T17:05:48Z http://repository.ou.ac.lk/handle/123456789/4330 Integrating Technology and Sustainable Practices: Developing an Eco-Friendly Framework for Sri Lanka’s Traditional Brass Craft Industry Raveesha Warshani, W. A.; Wijerathne, D.S Sri Lanka’s brass craftsmanship is an essential part of its material culture, native expertise and rural sustenance. The industry, mainly based in the Kandy region, involves casting, sheet forming, engraving, repousse, polishing and other artisanal skills handed down from one generation to the next. However, the long- term sustainability of the sector is being challenged by rising raw material costs, inefficient production techniques, changing consumer preferences, limited market access, technological barriers, and environmental impacts of metal smelting and declining interest among younger generations. This research analyses the ecological, financial, social and cultural aspects of conventional brass craftmanship in Sri Lanka to identify its viability. The study employed a mixed-method qualitative approach with emphasis on the brass manufacturing communities in the Pilimathalawa area of Kandy District. We conducted semi-structured interviews, field observations and process mapping to analyze material use, production methods, energy use, waste generation, the livelihoods of the artisans, knowledge transfer, and market dynamics. The research identifies opportunities to improve sustainability by using more brass scrap, smart material design, advanced melting systems, suitable digital fabrication techniques, responsible surface treatment methods, direct engagement with the market, skill upgrades, and generational knowledge transfer. The study proposes a sustainable crafting model, which integrates the traditional artistry with appropriate technological innovations, to preserve the cultural integrity of the Sri Lankan brassware. Thu, 01 Jan 2026 00:00:00 GMT http://repository.ou.ac.lk/handle/123456789/4330 2026-01-01T00:00:00Z http://repository.ou.ac.lk/handle/123456789/4323 Echo-Window Sensitivity of Spectral Features in Ultrasonic Backscatter Characterization of PE and PMMA Microplastics Pathirana, Nethruwan; Premarathne, U.S. Ultrasonic backscatter provides a non-destructive approach for characterizing microplastic particles; however, the spectral features extracted from an echo can depend on the signal segment selected for analysis. This study investigates the sensitivity of polyethylene (PE) and poly(methyl methacrylate) (PMMA) spectral-feature differences to echo-analysis window length using a publicly available high-frequency ultrasonic backscatter dataset. Signals sharing a common 50-μm size label were analyzed using peak-centered windows of 64, 128, 256, and 384 samples. After mean removal and Hamming tapering, spectral centroid, spectral spread, and normalized spectral entropy were extracted from the Fourier-domain representation. Spatially neighboring measurements were grouped before statistical comparison to reduce the influence of repeated local observations. The results show clear feature-dependent window sensitivity. The PE–PMMA centroid difference remained comparatively stable, changing by only about 3.2% between the shortest and longest windows, whereas the spectral-spread difference increased by approximately 115%. Spectral entropy also showed substantial but non- monotonic variation with window length. These findings demonstrate that echo-analysis window selection is an important digital signal processing parameter and should be considered when evaluating the robustness and reproducibility of ultrasonic spectral features for microplastic characterization. Thu, 01 Jan 2026 00:00:00 GMT http://repository.ou.ac.lk/handle/123456789/4323 2026-01-01T00:00:00Z http://repository.ou.ac.lk/handle/123456789/4322 DEVELOPMENT AND THERMAL PERFORMANCE EVALUATION OF A PCM-ENHANCED CONCRETE PAVEMENT FOR SURFACE TEMPERATURE REDUCTION IN TROPICAL CONDITION Jayasundara, J.M.I.S.; Athapattu, B.C.L.; Andradi, D.M.A.S.R. The urban heat island (UHI) effect is an important environmental challenge in rapidly developing urban areas, where built surfaces can reach substantially higher temperatures than surrounding areas. Pavement materials contribute to this phenomenon by absorbing and storing solar energy during daytime exposure. This study investigates the thermal and mechanical performance of a phase change material (PCM)- enhanced concrete pavement developed to reduce pavement surface temperatures under tropical outdoor conditions. Paraffin wax was selected as the PCM because of its phase-change temperature range suitable for the experimental conditions, while expanded clay aggregate (ECA) was used as a porous carrier for PCM incorporation. Four pavement mixtures containing 0%, 3%, 6%, and 9% PCM-integrated ECA were prepared, with the PCM-containing material incorporated within the upper surface layer of the pavement specimens. The thermal performance was evaluated through outdoor monitoring over a 15-day period at one-hour intervals. Compressive strength was evaluated at 7, 14, and 28 days, while flexural strength was evaluated at 28 days. The results showed that PCM incorporation reduced the peak pavement surface temperature compared with the control specimen. The 3%, 6%, and 9% PCM mixtures reduced the peak surface temperature by approximately 3.5 °C, 6.0 °C, and 6.5 °C, respectively. Although increasing PCM content improved thermal performance, the additional reduction between 6% and 9% was relatively small. The 6% PCM mixture provided a balance between thermal performance and mechanical strength, with a reported 28-day compressive strength of 27 MPa and flexural strength of 3.12 MPa. The findings indicate that PCM-integrated concrete pavement has potential for reducing pavement surface temperatures under tropical outdoor conditions. However, further investigation is required to evaluate long-term durability, environmental implications, thermal cycling behaviour, and the potential contribution of the technology to urban-scale UHI mitigation. Thu, 01 Jan 2026 00:00:00 GMT http://repository.ou.ac.lk/handle/123456789/4322 2026-01-01T00:00:00Z http://repository.ou.ac.lk/handle/123456789/4321 Sustainable Natural Feed Optimization and Low-Cost Automated Feeding Systems for Small-Scale Dairy Farms in Sri Lanka Madushani, S.H.G.; Premarathne, U. S. Small-scale dairy farming is an important contributor to Sri Lanka's agricultural sector, yet productivity and sustainability are limited by inefficient feeding practices, dependence on expensive commercial feed, and limited access to modern technologies. This paper proposes CattleCare, an integrated framework that combines a web-based advisory platform with a low-cost automated feed dispensing system to support sustainable feed management for smallholder dairy farmers. A field survey conducted across 16 dairy farms between March and June 2026 collected data from approximately 60 cattle representing indigenous and crossbred dairy breeds. The platform analyzes existing feeding practices and generates customized feeding recommendations based on cattle characteristics, milk production, environmental conditions, and locally available feed resources. The framework is designed to interface with a low-cost automated feed dispensing system for accurate feed allocation, with field validation planned under real farm conditions. By promoting the use of locally available fodder, agricultural by-products, and affordable digital technologies, the proposed framework supports circular agricultural practices while reducing reliance on imported concentrate feeds. Preliminary field observations demonstrate the practical potential of the proposed framework for supporting structured feed management; however, long-term effects on milk productivity, feed efficiency, and environmental performance require further validation. Thu, 01 Jan 2026 00:00:00 GMT http://repository.ou.ac.lk/handle/123456789/4321 2026-01-01T00:00:00Z