Faculty of Engineering
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Publication Open Access Recent Technological Progress of Fiber-Optical Sensors for Bio-Mechatronics Applications(MDPI, 2023-11-07) Abdhul Rahuman, M.A; Kahatapitiya, N.S; Amarakoon, V.N; Wijenayake, U; Silva, B.N; Jeon, M; Kim, J; Ravichandran, N.K; Wijesinghe, R.EBio-mechatronics is an interdisciplinary scientific field that emphasizes the integration of biology and mechatronics to discover innovative solutions for numerous biomedical applications. The broad application spectrum of bio-mechatronics consists of minimally invasive surgeries, rehabilitation, development of prosthetics, and soft wearables to find engineering solutions for the human body. Fiber-optic-based sensors have recently become an indispensable part of bio-mechatronics systems, which are essential for position detection and control, monitoring measurements, compliance control, and various feedback applications. As a result, significant advancements have been introduced for designing and developing fiber-optic-based sensors in the past decade. This review discusses recent technological advancements in fiber-optical sensors, which have been potentially adapted for numerous bio-mechatronic applications. It also encompasses fundamental principles, different types of fiber-optical sensors based on recent development strategies, and characterizations of fiber Bragg gratings, optical fiber force myography, polymer optical fibers, optical tactile sensors, and Fabry–Perot interferometric applications. Hence, robust knowledge can be obtained regarding the technological enhancements in fiber-optical sensors for bio-mechatronics-based interdisciplinary developments. Therefore, this review offers a comprehensive exploration of recent technological advances in fiber-optical sensors for bio-mechatronics. It provides insights into their potential to revolutionize biomedical and bio-mechatronics applications, ultimately contributing to improved patient outcomes and healthcare innovation.Publication Open Access Vertically constructed wetlands for greywater reuse: Performance analysis of plants(Elsevier, 2023-10-02) Siriwardhana, K.D; Miguntanna, N; Jayaneththi, D. I.; Kantamaneni, K; Rathnayake, UVertical Flow constructed wetlands (VFCWs) are environmentally feasible engineered systems that mimic the functions of natural wetlands. They are alternative engineering systems that are economical, and simple in structure with reduced land area compared to Horizontal Flow Constructed Wetlands (HFCW). Thus provides a sustainable solution for greywater treatment to a considerable extent. However, VFCWs feasibility and plant performance were not tested in the context of Sri Lanka for the greywater treatment. Therefore, the purpose of this study is to evaluate the potential of household greywater treatment using a pilot-scale VFCW and examine the performance characteristics of different types of plants. Three types of plants, the Canna plant (Canna indica), Ferns plant (Matteuccia struthiopteris), and Cattail plant (Typha latifolia) were used as emergent plants and a retention tank was constructed to retain solid particles in the greywater as primary treatment. The experiments were carried out for two months using a Completely Randomized Design (CRD) for three replicates. The quality of the influent and effluent was tested fortnight for a number of water quality parameters. Results revealed that the removal efficiency of contaminants was increased. Cattail plants showed higher removal efficiency for dissolved oxygen (DO), chemical oxygen demand (COD), nitrates (NO3 1-), turbidity, and electrical conductivity. In addition, Canna plants had higher efficiencies for the removal of total dissolved solids (TDS) and phosphates (PO4 3-). Furthermore, Ferns plants presented higher efficiency only for removing sulphate (SO4 3-). Conclusively, Cattail plants presented the overall best performance in treating greywater. This can be attributed to the ability of the Cattail’s dense fibrous root system to absorb more contaminants from greywater. This research also discussed the importance of microplastic analysis in greywater treatment which is a vital part of the current day research. The results of this study will be helpful to the further advanced research. Furthermore, this methodology can be implemented to other similar plants across the globe irrespective of geographical area.Publication Open Access Strategic implementation of PPP for small-scale infrastructure in Sri Lanka: a comparative analysis of alternative PPP models(Ceylon Institute of Builders - Sri Lanka, 2023-07-21) Guruge, K; Coomasaru, P; Weeraman, CThis study aims to provide a thorough comparison of Private Finance Initiative (PFI), Build-Operate-Transfer (BOT), and Joint Venture (JV) models for Small-Scale Infrastructure Development (SSID) in Sri Lanka and devise innovative, tailored recommendations to maximise efficiency, effectiveness, and compatibility. Employing a mixed-methods approach, the research systematically examines the key features, benefits, and limitations of PFI, BOT, and JV models in the context of SSID. A compatibility assessment is conducted, focusing on financing approaches, stakeholder engagement, and other critical success factors. The findings reveal that the BOT and JV models are superior to the PFI model due to their balanced stakeholder engagement, risk sharing, and alignment with critical success factors. Based on these insights, the study formulates novel, customised recommendations for optimising the selected model's efficiency, effectiveness, and compatibility with SSID in Sri Lanka, with the aim of informing policy and practice. Furthermore, the study highlights the need for future research exploring alternative financing models and emerging technologies in SSID, opening new avenues for innovative approaches to infrastructure development in Sri Lanka. In conclusion, this comprehensive comparison offers valuable guidance for academics, industry professionals, and policymakers seeking to enhance small-scale infrastructure development in Sri Lanka, emphasising the importance of selecting the most suitable financing model.Publication Open Access AN IOT-BASED ELECTRICAL AND ELECTRONIC APPLIANCE MANAGEMENT SYSTEM FOR SRI LANKAN RESIDENTIAL BUILDINGS(Ceylon Institute of Builders - Sri Lanka, 2023-07-21) Liyanage, D.L.C.P; Anuradha, I.G.N; Kumarathunga, J.U; Kalugala, C; Samarakoon Arachchige, D.SSri Lankan household energy consumption was accounted for around 34% of national energy consumption in 2017, and residential applications were accounted for 36% of national energy waste in 2018. Therefore, reducing the energy wastage in the household environment is essential. Researchers from all around the world are working to develop IoT-based solutions to reduce energy wastage, but there are certain challenges in adapting them to the local context as those techniques were developed for foreign domestic usage. As a result, it is crucial to come up with IoT-based solutions which are appropriate for the local environment to assist the reduction. Therefore, this article examines the importance and feasibility of adopting IoT-based electrical and electronic device control systems for household use in Sri Lankan environments. Further, a mobile application was developed to monitor and control the system, which was installed for a residential building after an analysis of the domestic requirements. This system may simply fix into an existing building, making it a cost-effective application for reducing energy wastage in developing countries.Publication Open Access POTENTIAL IMPACTS OF BLOCKCHAIN TECHNOLOGY IMPLEMENTATION ON CONSTRUCTION CONTRACT MANAGEMENT IN SRI LANKA(Construction Contract Management, 2023-07-21) Karunaratne, B.C.T.M.; Abeynayake, D.N.The construction contract is the mainstay for the ascendancy of the construction project requiring proper contract management. The Sri Lankan construction industry has many complications associated with contract management. Blockchain, as a decentralised transaction and data management technology, can potentially address the issues related to contract management amidst the impediments to effective implementation. However, blockchain technology adaptation in the Sri Lankan construction industry lacks evidence, even though other sectors, for example, banking and agriculture, are with the initial implementation. Hence, this research aimed to identify the potential impacts of implementing blockchain technology in construction contract management in Sri Lanka. A literature review was conducted to identify the concept of blockchain technology, its applications and its benefits. A qualitative survey strategy was adopted, and data were collected via semi-structured interviews in two phases; Phase I with ICT and finance industry experts and Phase II with construction contract experts. Samples were selected purposively through snowball sampling. The data analysis revealed that the awareness and use of blockchain technology in Sri Lanka are relatively low. However, Sri Lanka has the potential to adopt Blockchain in different fields, depending on their capabilities. Furthermore, the study found associated positive impacts of Blockchain, e.g., avoiding complex procedures, providing transparency, no ambiguities, no human errors and reducing political influence to mitigate contract management issues. Besides, Blockchain may negatively impact due to, e.g., high initial and maintenance costs, lack of knowledge and expertise, unavailability of rules and regulations, and reluctance to change those need mitigations.Publication Open Access A STUDY ON THE PHYSICAL AND MENTAL HEALTH ISSUES TO THE NEIGHBOURING RESIDENCES DUE TO THE CONSTRUCTION PROJECTS IN SRI LANKA(Ceylon Institute of Builders - Sri Lanka, 2023-07-21) Arjuna, M.P.; Edirisinghe, V.; Manoharan, K.; Herath, S.S.This study investigates the physical and mental health issues experienced by neighbouring residences as a result of construction projects in Sri Lanka. Specifically, it examines the impact of these projects on respiratory distress, hearing impairments, traffic congestion, lack of landscape, and flooding conditions. Additionally, the study explores the psychological effects on residents and emphasises the importance of health and safety measures in project management. Data collection involved conducting interviews with project managers, site safety officers, and a male nurse from three selected construction sites, followed by a questionnaire survey administered to 30 neighbouring residents. The study provides recommendations to mitigate adverse impacts, raise community awareness, and promote environmentally friendly practices in the construction industry. The findings enhance understanding of the health challenges faced by neighbouring residents and offer insights to policymakers and project managers to improve the well-being of affected communities.Publication Open Access IMPACT OF ECONOMIC CRISIS ON EMPLOYEES OF CONTRACTORS’ ORGANISATIONS IN THE SRI LANKAN CONSTRUCTION INDUSTRY(Ceylon Institute of Builders - Sri Lanka, 2023-07-21) De Silva, S.S.; Wijekoon, W.M.C.L.K.; Kalugala, CThe construction industry contributes more than 6% of the GDP of the Sri Lankan economy, employing workers at different levels of the value chain. The economic crisis in the country from 2019-2022 has had a significant impact on contractors’ organisations in the Sri Lankan construction industry, resulting in job losses, pay cuts, and reduced working hours. Hence this study aims to investigate the impact of the economic crisis on the employees of contractors’ organisations in the Sri Lankan construction industry, the most affected level of employees, and propose strategies to minimise the impact on the most affected level of employees. This study has been done using the mixed-method approach. Thirty-three (33) employees participated in a questionnaire survey and seven (7) managerial-level professionals were interviewed who are currently engaged in construction projects. This study has explored the levels of employees including technical, supervisory, and similar levels, professional level, administration, and managerial level. Further, this study provides the strategies adopted by the employees and the contractors to overcome the impact of the crisis, including measures to enhance productivity, cost reduction strategies, and access to financial support. The findings of the study will provide insights into the impact of the economic crisis on the construction industry in Sri Lanka and inform policy recommendations to support affected workers and ensure the long-term sustainability of the industry in a resilient wayPublication Embargo Comparative quantifications and morphological monitoring of the topical treatment approach for onychomycosis-affected in vivo toenail using optical coherence tomography: A case study(Elsevier, 2023-10-19) Saleah, S. A; Gu, Y; Wijesinghe, R.E; Seong, D; Cho, H; Jeon, M; Kim, JOnychomycosis is one of the most common toenail fungal infections that affect the quality of life of many patients. Long-term and noninvasive monitoring of morphological changes of onychomycosis-affected nail plate aids the medication process and provides comfort for patients. However, existing medical and dermatological imaging methods have various types of limitations in nail investigation due to low resolution, lack of volumetric data, the necessity of highly trained personnel for image analysis, and the variety of protocols. In this study, qualitative monitoring-based quantitative assessments were performed to assess the morphological changes of onychomycosis-affected toenail for 15 consecutive weeks using high-resolution optical coherence tomography (OCT). Layer intensity and surface roughness measuring algorithms were applied to two-dimensional OCT cross-sectional images to detect gradual changes in the morphological structure of the diseased toenail. A depth intensity profile and the angle formed between the nail plate and nail fold were also used to analyze the thickness and shape of the toenail plates, respectively. The quantitative and morphological monitoring results revealed significant changes in the toenail structure before and during the treatment process, confirming the healing of the diseased toenail. Therefore, the proposed noninvasive optical analysis approach can be applied to monitor nail abnormalities and evaluate the process of diseased toenail medication.Publication Open Access Label-free visualization of internal organs and assessment of anatomical differences among adult Anopheles, Aedes, and Culex mosquito specimens using bidirectional optical coherence tomography(Elsevier, 2023-08-02) Luna, J.A; Ravichandran, N.K; Saleah, S. A; Wijesinghe, R.E; Seong, D; Choi, K.S; Jung, H.Y; Jeon, M; Kim, JMosquitoes transmit several fatal human diseases and constitute a global threat to the fight against infectious diseases. Thus, it is crucial to identify the diseases transmitted by mosquitoes, analyze their internal organs, investigate the life cycles of the viruses and pathogens they carry, and elucidate the anatomical changes they cause inside the host without dissecting them. Here we have demonstrated a method for label-free visualization of the internal organs of adult Anopheles, Aedes, and Culex mosquitoes using swept-source optical coherence tomography (SS-OCT). To overcome the limitation of depth-dependent signal-to-noise ratio (SNR) reduction, imaging was conducted using a dynamic rotational OCT scanner to acquire images of the top and bottom surfaces of the specimens. The internal structure and organ images of all the mosquito specimens had constant resolvability and higher SNR than in those obtained via conventional OCT. Furthermore, a depth profiling algorithm was developed to obtain quantitative information about the internal organs. Several internal organs, such as the salivary glands, heart, midgut, dorsal and ventral crop, and abdominal ganglia, were precisely identified and analyzed noninvasively using OCT. The average thicknesses of the heart, midgut, dorsal and ventral crop, and abdominal ganglia of Anopheles, Aedes, and Culex mosquitoes were 72.1, 107.3, 87.3, and 63.4 μm, respectively. This study demonstrates the applicability of OCT in entomology research for high-resolution microscopic analysis. The findings of this study can guide future studies requiring nondestructive assessment of internal organs to evaluate the morphological differences among various virus-transmitting mosquito specimens.Publication Embargo Relationships amongst water and sediment qualities, discharge, and allochthonous inputs of intermittent streams in tropical dry climates: Implications on stream management(Elsevier, 2023-07-19) Gomes, P.I.A; Perera, M.D.DThe interrelationships amongst water and sediment physicochemistry, catchment hydrology, and allochthonous inputs are not well established for intermittent streams, especially in tropical climates. This remains a major concern in water resources management, and understanding these streams is vital in forming targeted frameworks for protection. A two-year comprehensive study showed spatially independent water quality variations, where similar temporal patterns were observed in different streams in close catchments for many variables (such as for electrical conductivity, pH, nitrogen species, and dissolved oxygen). This was not the case for sediment quality variables; in addition, in-stream variation was high. This gave an indication of the regulatory potential of intermittent stream sediment. Redundancy analysis models showed that stream water quality was significantly correlated to, and could be explained by discharge, rainfall parameters, litter, and sediment quality. Sediment quality was not influenced by litter inputs but by discharge and rainfall-related parameters. The study reported new insights into the unique physicochemistry of intermittent streams and proposes the fact that sediment quality needs comprehensive monitoring and management both spatially and temporally.