SLIIT International Conference On Engineering and Technology Vol. 01 [SICET] 2022
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Publication Open Access Aspects of Structural Vulnerability against Tsunamis(SLIIT, Faculty of Engineering, 2022-02-11) Dias, PUsing historical data, it is shown that tsunamis may not occur for earthquake magnitudes even up to Mw = 8. Field data can be used to arrive at generalized fragility curves for different materials of construction as functions of inundation depth. Such curves can also be integrated into vulnerability curves that can be characterized by simple negative exponential equations. It is also possible to create synthetic fragility curves generated by Monte Carlo simulation, which were found to have a reasonable fit with the empirical ones. While most simulations focus only on the structural frames in buildings, partitions can also play a significant role in damage mechanisms. There is also a role for simplified indices of either risk or robustness, based ideally on physics rather than expert opinion. Such indices can also be used to consider risk to an entire system, for example buildings, functions and backup services that are spread across adjacent coastline hospitals.Publication Open Access Intelligent Robotics—Misconceptions, Current Trends and Opportunities(SLIIT,Faculty of Engineering, 2022-02-11) de Silva, C. WThe concepts of “Robots” have been of interest to humans from the historical times, initially with the desire to create “artificial slaves.” Since the technology was not developing to keep up with the “dreams,” initially Robotics was primarily of entertainment value, relegated to plays, movies, stories, and so on. The practical applications started in the late 1950s and the 1960s with the development of programmable devices for factories and assembly lines, as flexible automation. However, since the expectations were not adequately realized, the general enthusiasm and funding for Robotics subsided to some extent. With subsequent research, developments, and curricular enhancement in Engineering and Computer Science and with the resurgence of Artificial Intelligence (AI), particularly machine learning, Robotics has found numerous practical applications today, in industry, medicine, household, the service sector, and the general society. Important developments and practical strides are being made, particularly in Soft Robotics, Mobile Robotics (Aerial—drones, Under Water, Ground-based—autonomous vehicles in particular), Swarm Robotics, Homecare, Surgery, Assistive Devices, and Active Prosthesis. This talk will start with a brief history of Robotics while indicating some associated myths and unfair expectations. Next it will outline key developments in the area. In particular, some important practical applications of Intelligent Robotics, as developed by groups worldwide including the Industrial Automation Laboratory at the University of British Columbia, headed by the author, will be indicated. Some misconceptions and shortcomings concerning Intelligent Robotics will be pointed out. The main shortcomings concern the mechanical capabilities and the nature of intelligence. The talk will conclude by mentioning future trends and key opportunities available in Intelligent Robotics, for both developed and developing counties.Publication Open Access Converter Control for Integration of Renewable Energy into the Grid(SLIIT, Faculty of Engineering, 2022-02-11) Annakkage, UGeneration of electricity using renewable sources of energy will be the only option available to us soon. This may happen within the next two decades. In the meantime, we make the transition form traditional synchronous generator driven power systems to fully renewable energy-based power systems where the energy source is integrated through power electronics converters. We must start thinking in a new way. This presentation will address the technological challenges associated with connecting renewables to the grid through converters and the options available to meet those challenges. While the ability of the converters to respond fast is an obvious advantage, unlike the synchronous generator, it does not have a rotating mass that stores kinetic energy. The short-term overcurrent rating of the converter is much less than that of a synchronous generator unless the converter is overdesigned. Addressing these engineering challenges will be discussed in the presentation.Publication Open Access A Study on Local Air Pollution Due to Transport Emissions in Kandy City(SLIIT, 2022-02-11) Yatigammana, S; Fernando, G; Liyanage, MAir pollution has become one of the greatest challenges that the world is facing today. According to World Health Organization (WHO)there are 4.2 million annual deaths due to outdoor air pollution. Furthermore, about 90% of global population breathe polluted air. The most harmful cause of outdoor air pollution is recognized to be unorganized traffic management. In the instance of Sri Lanka, Kandy city has been recognized as crucial where necessary actions are required to be taken. This study presents harmful emission values produced by a daily count of vehicles entering the city alongside respiratory diseases and illnesses recorded. Detailed analysis provides pollutant emissions due to unorganized traffic management within Kandy city concentrating over locations from Getambe Junction to Kandy Clock tower and from the city centre towards Mahaiyawa Tunnel and Ampitiya Junction (locations are pinned on figure 1). Calculation of pollutant factors are intended to be done using three main methods namely, Tier 1, Tier 2 and V/C ratio method aided by vehicle fuel type, fuel efficiency, travelled distance and carriageway congestion values. Emission values for pollutants Carbon monoxide (CO), Nitrogen oxides (N2O, NOX) and Sulphur dioxide (SO2) were identified in this study along with PM2.5 and PM10 values. It was to be seen that, over 100,000 vehicle cross Kandy city limits on both weekdays and surprisingly higher values in weekend with each carriageway within the city resulting over a 65% of congestion value. With 31% of daily trips being travel to work, the public transport system fails to deliver its purpose efficiently and effectively. With unorganized traffic management, stagnant and slowmoving vehicles tend to pollute 41% more SO2 and 14% more NOX gasses above global standards affecting the first five kilometers from the city center, which claimed to facilitate the zone of highest quality of life. Current records show PM2.5 values in Kandy to read above 50μg/m3 and PM10 values to be as high as 100μg/m3.Publication Open Access Cryptocurrency Price Prediction: A Comparative Study using LSTM, GRU and Stacking Ensemble Algorithm for Time Series Forecasting(SLIIT, 2022-02-11) Ashikul Islam, M. DTechnology has significantly reshaped how humans interact with their tangible and intangible surroundings. Cryptocurrency is considered to be one of the most recent technological inventions which revolutionized how we perceive currencies and their functionality. It has become popular because of its safety, security and anonymity. However, volatility remains one of the major issues with cryptocurrencies to this day. Therefore, the primary aim of this paper is to develop LSTM (Long ShortTerm Memory), GRU (Gated Recurrent Units) and a Stacking Ensemble Learning algorithm that efficiently predicts the price of a cryptocurrency for a given period of time. The predictions are then observed and analysed to determine the comparative performance of the said algorithms.Publication Open Access Causes for Death and Injuries in Construction Industry in Sri Lanka(SLIIT, 2022-02-11) Wijesekara, M; Fernando, P; Gunarathna, NThe construction industry plays a vital role in the socio-economic development in any country. However, it has been recognized as one of the most hazardous industries in many counties around the world because of the nature of activities and tasks performed at construction sites. Similarly, presentday construction industry of Sri Lanka prioritizes and considers safety as a primary, complex issue due to its high impact on the industry. Accordingly, the aim of this study was to identify the causes for deaths and injuries in construction sites in Sri Lanka and identify actions to mitigate those accidents. The data collection was in the form of documentary review, semi-structured interviews, and questionnaire survey. This study found that the nine (9) most prominent types of accidents that have occurred in Sri Lankan construction sites include falling from heights and scaffoldings, falling debris or objects and machinery accidents. During the last 10-year period 2,135 accidents have been recorded in the construction industry, including both fatal and non-fatal accidents, among which 311 were fatal accidents. As per the study findings, during the period of 2010 – 2020, 14 fatal construction accidents were reported out of every 100 construction accidents. Usually, most of the accidents at construction sites are due to lack of safety at site, working without PPE, inadequate training and lack of supervision. Further, the study also recommends strategies to minimize the identified nine (9) most prominent types of accidents and to improve construction site safety. Findings of this research could help towards reducing the fatal and non-fatal construction accidents in Sri Lanka and to develop safe work environment in the local construction industry.Publication Open Access Challenging Arbitral Awards in the Construction Industry(SLIIT, 2022-02-11) Jayasinghe, R; Dahanayake, R; Edirisinghe, VOne of the most common alternative dispute resolution methods used in the Sri Lankan construction industry is arbitration. However, challenging arbitration awards based on legal grounds at the courts has been a current trend by the disagreeing party. If this situation occurs continuously, the purpose of having arbitration as an alternative dispute resolution method can be abandoned. Therefore, the study aims to identify the causes where arbitration is challenged in multi-story building construction projects in Sri Lanka through a case study. The methodological choice was qualitative and used semistructured interviews from six arbitrators and 2 case studies that referred to courts to challenge arbitration awards as research strategies. The study found the poor attitude of parties, lack of technical knowledge, reliability, and capability of the arbitrator to act according to the arbitrary acts imposed by the government as the main causes. Further. The study recommends arbitrators consider the reasons to act well enough and reject the cases if the arbitration is likely to be challenged in courts, train arbitrators to be reliable and on technical knowledge, and improve parties' attitudes by educating on the arbitration procedure and its benefits.Publication Open Access Experimental investigation of concrete-filled and bare 6082-T6 aluminium alloy tubes under in-plane bending(SLIIT, 2022-02-11) Kamaris, G. S; Gkantou, M; Kansara, K. D; Bin Al, SThe application of aluminium alloys in construction sector is increasing owing to their excellent corrosion resistance, light weight and attractive appearance. However, one of the main disadvantages of aluminium alloys is the low elastic modulus, which may cause a stability issue in aluminium structural members. The performance of aluminium tubes can be improved by filling concrete within them. Research on the flexural behaviour of concrete-filled aluminium alloy tubes is limited. This paper presents an experimental study on the behaviour of square and rectangular concrete-filled and bare aluminium tubular sections subjected to in-plane bending. Total 20 beams were tested, including 10 concrete-filled aluminium tubes (CFAT) and 10 bare aluminium tubes (BAT). The hollow aluminium tubes were fabricated using 6082-T6 alloy and filled with 25 MPa cylinder compressive strength concrete. The material properties of aluminium were measured by tensile test of coupons. It is shown that the flexural strength, stiffness and ductility of square and rectangular BAT flexural members was remarkably improved by the infilled concrete and the improvement is more pronounced for the thinner aluminium sections. Due to absence of design standards for CFAT beams, in this study the design rules available for concrete-filled steel tubular flexural members in the Eurocode 4 are considered by substituting the mechanical properties of steel with those of aluminium alloy. It is demonstrated that the proposed design rules provide good predictions of the flexural capacity of CFAT.Publication Open Access Design and Fabrication of a Novel Hybrid Solar Dryer(SLIIT, 2022-02-11) Perera, C; Fernando, G; Liyanage, MA hybrid solar dryer was designed and tested for commercial dissemination of active and passive drying methods over traditional sun drying methods. The proposed dryer employs novel features such as user controllability of the drying parameters and includes sensors and controllers for active monitoring of drying parameters. The functionality of the dryer is broadened by using logic control whereby intermittent drying patterns are introduced to the system for more efficient operation. This paper documents the design calculations and fabrication process of the dryer as well as the results of drying obtained under a controlled environment. 10 experiments have been carried out to assess the limits and potential improvements to the system which yielded satisfactory conditions with a temperature fluctuation of ±1℃ and change in %RH of ±2% at any given temperature within the specified limits. The developed system has been used for drying apples which yielded dried products from an initial weight of 346 grams to a final weight of 55 grams in 5 hours in pure convection and the same initial weight was reduced to 52 grams in 3 hours when operating in solar hybrid mode. The average energy consumption of the dryer was obtained at 300 Watts at uninterrupted solar insolation operation and 224 Watts during pure convective operation, portraying the efficient operation of the system to be eligible to be powered by a solar-powered energy storagePublication Open Access Aeroacoustic Noise Produced from Novel Wind Turbine Rotor Design for Small-scale Applications in Sri Lanka(SLIIT, 2022-02-11) Perera, M; Bandara, U. HGrowing concerns regarding non-renewable energy sources have driven academic and industrial scholars as well as global superpowers to seek sustainable, greener power generation alternatives. One such prominent renewable substitute is wind power which was initially utilized in harnessing electricity towards the late nineteenth century though archaeological evidence has proved that wind power had been employed for various purposes since predynastic Egypt. Extensive research and development has enabled the efficient operation of multi megawatt wind farms at present though inherent drawbacks still persist, of which aerodynamic noise, also referred to as aeroacoustic noise, is of major concern. This paper details the simulative investigation of the aeroacoustic sound levels produced by an optimized novel wind turbine design intended for the use in small scale applications with medium wind speed conditions in Sri Lanka, using ANSYS Fluent. A transient analysis using the Shear Stress Transport turbulence model was used to obtain the converged pressure fluctuations which subsequently revealed the sound pressure levels via Fast Fourier Transforms at six predetermined locations of interest. The results revealed the presence of acoustic vibrations within the Infrasonic and Low Frequency Noise range with sound pressure levels exceeding one hundred decibels, particularly up to a frequency of twenty five Hertz. Prolonged exposure to elevated levels of low frequency noise has been identified to cause severe discomfort to humans though further conclusive research is required. Finer mesh controls which incorporate minute boundary layer variations during motion and precisely encapsulate the turbine geometry could further improve the accuracy of the results, however this would require adequate computational capacity. The results of this research primarily serve as a basis for identifying possible improvements for the novel rotor design in addition to providing a comparative study for future research, both simulative and empirical, on the aerodynamic noise emissions associated with wind turbines.