ICAPS 2023
Permanent URI for this collectionhttp://repository.kln.ac.lk/handle/123456789/26832
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Item Facebook Network Analysis Based on Graph Theory(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Koralegedara, H. C.; Weerasinghe, M. H. L.In the present world social media has become an essential part of humans' life. Most people use social networks to do their day today life activities. Analyzing real world social networks is also a very important and emerging research area. This research work mainly focused on Facebook social network and analyzed its properties using graph theory concepts. The network is assumed as a graph, that is, a set of vertices (or nodes) representing a person and a set of lines (or edges) representing one or more social relations among them. Graph theory techniques and properties help to analyze and visualize the behavior of networks. To construct our Facebook network, we collected real world data set by doing survey from group of university students. According to our data set we construct a network with 221 nodes and 698 edges to represent our Facebook model. To construct the Facebook model, we used Gephi, which is an open-source software for analyzing and visualizing networks. Real world networks are very complex and massive, and it is not easy to analyze. To analyze our Facebook network model, we basically used content analysis under the following categories such as metric, network structure, temporal, random walks, and visualization. Network metrics identify the most important or central character of the network. Under metric analysis we discussed homophily, density, centrality, and transitivity those are measure principal nodes in a network tends to have links to other nodes, how close the network is to complete, the most influential character of the network and tendency of the nodes to cluster together, respectively. In our model graph density is very low compared with complete. Closeness centrality is very low in the network and it is represented the connections among the people who are in the network is very distant. In the network structure basically discussed how we explore network from its structure, based on two areas such as network features and community detection. The page rank, Hyperlink – Induced Topic Search (HITS) and Stochastic Approach for Link Structure Analysis (SALSA) discussed under random walk. Random Walks is a path across a network created by taking repeated random steps. By temporal we analyze the explicit time dependent properties of the network. Probabilistic ties, time aggregated, media matrix, multi agent and discretization discussed under temporal. Visualization of the network is important, but it is impractical with the very large dataset. This work mainly focusses on analyzing our constructed Facebook model using graph theory properties. The method we used can be applied to find many interesting information in social networks.Item Investigation of antioxidant and antityrosinase activities of Premna serratifolia(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Katpaharajah, G.; Weerasiri, K. C.In recent times, cancer and hyperpigmentation have been the most problematic issues faced by the people. As cancer is caused mostly by the free radicals in the body, antioxidants, which are radical scavengers, may reduce the mutations in the body. Hyperpigmentation is reduced by the compounds inhibiting the tyrosinase enzyme’s activity. So, the compounds responsible for antioxidant and antityrosinase activities are analysed. Many harmless bioactive compounds responsible for many bioactivities are present naturally in plants. For this research work, the Sri Lankan species Premna serratifolia was chosen as the focal subject with specific attention to its leaves, traditionally employed for alleviating ingestion related issues. Considering the absence of prior research on this plant in previous studies, the leaves and twigs were chosen to determine the antioxidant and antityrosinase activities. The leaves were extracted by maceration process (cold extraction) through a sequential extraction using hexane, ethyl acetate and methanol. The twigs were extracted using the Soxhlet apparatus (hot extraction) through a sequential extraction using ethyl acetate and methanol. The antityrosinase activity was determined by the tyrosinase enzyme’s catalytic reactions. The methanol extracts of leaves and twigs show higher antityrosinase activity (the IC50 value of leaves is 6.83 ± 1.31 mg/mL and the IC50 value of twigs is 8.20 ± 5.54 mg/mL) than their respective ethyl acetate extracts (IC50 value of leaves is 87.06 ± 54.90 mg/mL and IC50 value of twigs is 168.82 ± 2.60 mg/mL). The methanol extracts of leaves and twigs show similar antityrosinase activity within the concentration range of 0.200 – 1.600 mg/mL. At a concentration of 0.025 mg/mL, the methanol extracts of leaves and the twigs show higher antityrosinase activity than the standard Kojic acid yet, the twigs show more than the leaves. In ethyl acetate extracts, at a concentration of 0.025 mg/mL, twigs show higher antityrosinase activity than the standard Kojic acid and the leaves. The DPPH-radical scavenging method was employed to determine the antioxidant activity. The EC50 values of ethyl acetate extracts of leaves and twigs are higher (2.63 ± 1.61 mg/mL and 3.89 ± 1.57 mg/mL, respectively) than their respective methanol extracts (1.21 ± 0.64 mg/mL and 1.10 ± 0.65 mg/mL). Despite the methanol extracts having lower EC50 values, indicating high potent antioxidant activity, the ethyl acetate extracts of leaves and twigs exhibit higher antioxidant activity within the concentration range of 0.025 – 0.800 mg/mL. In ethyl acetate extracts of leaves and twigs, at a concentration of 0.025 mg/mL, the leaves show highest antioxidant activity than the twigs, but the twigs show higher antioxidant activity than the leaves within the concentration range of 0.100 - 0.200 mg/mLItem Evaluating the nutritional compositions of king coconut husk waste (KCHW) biochar and ash: as feasible soil conditioners for coconut plantations(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Kowshalya, R.; Udumann, S. S.; Dissanayake, D. K. R. P. L.; Shamila, S. K.; Atapattu, A. J.King Coconut Water exports have swiftly surged, making it a prominent sector in Sri Lanka’s exports. However, this rapid growth has led to increased husk waste generation, prompting the search for eco-friendly disposal solutions. This study aimed to comprehensively assess the nutritional composition of King Coconut Husk Waste (KCHW) ash and biochar produced at varying temperatures. Employing a muffle furnace, biochar and ash from the husk were produced. Biochar was generated at temperatures of 300 °C, 400 °C, and 500 °C for 1-hour period, while ash was produced at temperatures of 400 °C, 500 °C, and 600 °C for 4 hours, as chosen pyrolysis conditions. The research outcomes underscore the significant influence of pyrolysis temperature on the chemical characteristics of both biochar and ash. Even though higher conversion efficacy was achieved at 300 °C for biochar (58.87 %) and at 400 °C for ash (9.73 %). The partially burnt feedstock was observed under 300 °C during biochar production. Notably, biochar produced at 300 °C exhibited the highest levels of total nitrogen (1.99%) and available phosphorus (0.50 %). At 400 °C, biochar showcased elevated levels of available nitrogen (0.08 %) and total magnesium (0.41 %). Biochar derived at 500 °C displayed the most pronounced content of total phosphorus (0.47 %), potassium (3.33 %), calcium (1.16 %), along with the highest available potassium (2.93 %), calcium (0.38 %), and magnesium (0.24%) levels. Ash produced at 500 °C exhibited the highest proportions of total potassium, calcium, and magnesium (16.16 %, 3.11%, and 1.78 %, respectively), alongside elevated levels of available potassium (12.40 %) and magnesium (1.87 %). Similarly, ash generated at 600 °C demonstrated the highest percentages of total (2.47 %) and available (2.27 %) phosphorus. Noteworthy is the finding that 400 °C yielded the highest levels of total nitrogen (2.27 %), available nitrogen (0.07 %), and magnesium (0.45 %). Furthermore, biochar produced at 300 °C manifested the highest fixed carbon and moisture content, while ash generated at 400 °C exhibited the highest fixed carbon content. Trace nutrient concentrations were most pronounced in the ash. The maximum electrical conductivity (EC) values were recorded at 600 °C (17.12 µS/cm) for ash and at 500 °C (2.31 µS/cm) for biochar. In conclusion, based on the investigation, it has been found that biochar and ash produced at 500°C have a higher nutrient content when compared to other temperature conditions. This highlights the potential use of King Coconut Husk Waste-derived biochar and ash as nutrient-enriched soil conditioners, with enrichment in nitrogen, phosphorus, potassium, and magnesium.Item Identification of soil erosion prone areas in Matale district in Sri Lanka using RUSLE model and bare soil index(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Jayasekara, J. M. P. M.; Mendis, C. C. D.; De Silva, K. V. N. T.; Kodikara, K. N.; Weerasinghe, V. P. A.The Matale District is situated in the Central Province of Sri Lanka. It is roughly 1,993 km2 in size and is in the foothills of the central mountain range. Matale District is vulnerable to soil erosion, which causes serious problems for the local environment and agricultural activities. Soil erosion in Matale District is primarily caused by several factors, including rainfall, land use, slope, soil type and conservation practices. This study aims to assess the soil erosion vulnerability in Matale District, Sri Lanka, utilizing the Revised Universal Soil Loss Equation (RUSLE) model and Bare Soil Index (BSI). RUSLE Model, a Digital Elevation Model (15 * 15m), rainfall data, land use and land cover, soil maps, and cropping parameters were used to evaluate the severity of erosion throughout the Matale district. The RUSLE model was calibrated and utilized to determine the rates of soil erosion considering rainfall erosivity, soil erodibility, slope length and steepness, cover management, and conservation practices. Furthermore, the BSI was calculated using remote sensing techniques. The results of the study indicated that soil erosion vulnerability in Matale District varied significantly. The estimated annual average soil loss varied from 0 to 731.71t ha-1 yr-1 . Improved land management practices and forest cover were associated with lower rates of soil erosion, whereas steep slopes, poor vegetation cover, and intense land use practices were associated with higher rates. The BSI map further explains the soil erosion risk map. When comparing the BSI map with the soil erosion risk map, most of the areas with bare soil are prone to erosion. Paddy-cultivated areas, scrub lands, chena and other cultivated areas are prone to experience high levels of soil erosion when considering a land use map. The Red Yellow podzolic soil, Reddish Brown Earths, immature Brown Loams, Erosional remnants steep rock land, and various lithosols soil types are found in areas with severe soil erosion when comparing the soil and Soil Erosion Risk Maps. When comparing a slope map to a soil erosion risk map, areas with a high percentage of slope indicate high soil erosion. Areas with a low percentage of slope on a soil erosion risk map indicate less erosion. Based on the results, recommendations for soil conservation and sustainable land management strategies in the identified vulnerable areas in the Matale district include measures such as afforestation, contour farming, terracing, conservation agriculture practices, and education and awareness programs. This study contributes to understanding soil erosion vulnerability in Matale District and provides a foundation for further research and initiatives focused on sustainable land management and environmental conservation. Proper soil conservation practices should be implemented to safeguard natural resources, improve agricultural productivity, and assure long-term sustainability.Item Enhancement of physical properties of red clay based superior quality cookware.(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Dulaj, M.H.T.; Gunathilaka, H.M.B.I.; Arachchige, R.C.W.; Pandithavidana, D.R.; Kottegoda, I.R.M.Red clay-based cookware has been used for centuries mainly due to its aesthetic appearance, eco-friendliness as well as the ability to enhance the quality and taste of foods. However, at present, cookware manufacturers can't stay in business without freshcutting-edge properties because the growing demand for superior quality cookware that not only performs well but also has enhanced physical properties such as durability, resistance to cracking, and improved thermal shock resistance. As a remediation, the present study explores various techniques that can be employed to enhance the physical properties of red clay-based cookware, by adding reinforcing materials (Ball clay, Quartz, and Feldspar), varying firing temperatures, and advanced-manufacturing techniques like casting clay methods. Eight samples with different compositions were prepared using red clay, four different weight percentages were chosen for each clay type from 15 wt.%, 20 wt.%, 25wt.%, and 30 wt.% in Colombo and Beliattha samples. Their physical properties such as density of a casing clay slip, drying or firing shrinkage, loss on ignition, water absorption, modulus of rupture (MOR), and thermal shock resistance were investigated with repetition. Among the prepared samples, low shrinkage was observed in each clay type resulting reduced risk of defects from warping and cracking. Colombo clay is more suitable inthat respect. Due to higher MOR value, Beliatta clay has higher strength, durability, andstronger thermal shock resistance as well. Low water absorption was shown by Beliatta clay, indicating a more solid and impermeable structure, making the cookware lessprone to discoloration, cracking, or degradation. Therefore, Beliatta clay is more suitable than Colombo clay to fabricate cookware. Overall, it was found that different compositions of red clay could be successfully incorporated to improve the properties of claybased cookware. This study demonstrates that enhancement of the MOR value, low water absorption and low shrinkage for cookware manufacturers, researchers, and enthusiasts who are interested in improving the quality and performance of red clay-based cookware.Item Spatial and temporal variations in total iron concentration in the Kalatuwawa reservoir: a comparative analysis of different depths(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Harshana, K. G. E.; Thennakoon ., T. M. A. L. MThe aim of this study is to investigate the distribution of total iron concentration at different depths of the reservoir (near intake well) and its implications for water treatment at the Kalatuwawa Water Treatment Plant. Two sampling rounds were conducted using a depth sampler to collect water samples from six specific depths below the spillway: 10 ft, 15 ft, 20 ft, 25 ft, 30 ft, and 35 ft. The total iron concentration was determined using the APHA 3500 Fe-B test method. The results obtained on June 27, 2023, revealed varying total iron concentrations across the different depths. The concentration increased progressively with depth, ranging from 0.4 ppm at 10 ft to 1.26 ppm at 35 ft. On July 6, 2023, during the subsequent sampling round, the total iron concentrations exhibited slight fluctuations compared to the previous round, ranging from 0.36 ppm at 10 ft to 1.52 ppm at 35 ft. These findings highlight the spatial variation in total iron concentration within the Kalatuwawa reservoir, with higher concentrations observed at greater depths. The study emphasizes the importance of tailored treatment strategies to effectively remove or mitigate iron-related issues faced by the Kalatuwawa Water Treatment Plant. The identified variations in total iron concentration underscore the challenges in maintaining water quality and treatment efficiency. Further investigation is warranted to determine the sources and mechanisms influencing total iron concentration in the reservoir. The knowledge gained from this study will aid in the development of targeted treatment approaches to ensure the production of safe and highquality drinking water for the surrounding communities.Item Comparison of different methods for generating SPWM signal for the development of a pure Sine wave inverter(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Hemal, S. B. N. H.; Dilshan, G. K. D.; Karunarathna, M. A. D. D. S.; Morawakaarachchi, K. N.; Senanayake, S. V.; Premasiri, R. H. M. D.; Piyumal, P. L. A. K.; Ranaweera, A. L. A. K.An inverter is an electronic device which is used for converting Direct Current (DC) to Alternating Current (AC) because AC is the predominant form of electrical power used in homes, businesses, and most electrical appliances. Inverters can be categorized based on the type of waveform that they produce, such as Pure Sine Wave Inverters, Modified Square Wave Inverters and Square Wave Inverters. This paper discusses the development of a Pure Sine Wave Inverter with an output voltage of 230 VRMS and a frequency of 50 Hz using the Sinusoidal Pulse Width Modulation (SPWM) technique. Three SPWM signal generation methods, including analogue comparator, microcontroller, and SPWM driver module methods, were tested. This study presents a method to obtain a 230 VRMS, 50 Hz output sine wave in three steps. The first step involves the generation of an SPWM signal with frequency control, utilizing the DC source supply. The analogue comparator method uses op-amps as the analogue comparator. Then, it compares a reference sinusoidal wave with a high-frequency (in kHz range) carrier triangular wave. The output of the op-amp comparator is SPWM. The frequency of this reference sinusoidal wave is chosen based on the required inverter output frequency (50 Hz). In that process, the comparator gives out a pulse when the voltage of the sine waveform is greater than the triangular voltage, and this pulse is used to trigger the respective inverter switches. When designing a circuit that involves op-amps, the slew rate of the op-amp is a critical consideration. To generate an SPWM signal using an ATmega328p microcontroller, the microcontroller was used to generate a series of PWM signals by digital high and digital low. The corresponding time of each pulse's delay is added using the microsecond function. Increasing and decreasing duty cycle, and then a series of PWM signals. As the pure sine wave inverter SPWM driver module EGS002 was used and, that method was the more accurate method, and a clean SPWM signal was generated with less harmonics. Although this type of inverter board has more features, the circuitry was not complex because of the module. Secondly, we employ the MOSFET H-bridge stage to obtain the desired sine wave output. Finally, the third step focuses on supplying a high DC voltage to the H-bridge circuit, which the DC-DC PWM boost converter generates. Several circuit protections were included to ensure the device's safety and reliability. In the process of SPWM generation, although in the analogue comparator method, op-amps offer a low-cost option, a microcontroller is favoured for its superior precision and ability to handle high-power applications effectively. However, the EGS002 module stands out as the preferred method due to its user-friendly nature, comprehensive protection features, and ability to provide valuable feedback, making it a more economically efficient choice in the overall design.Item Computational investigation of novel Curcumin derivatives as anti -Tuberculosis Agents(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Amarasena, M. W. K. A.; Dahanayake, J. N.Tuberculosis (TB) remains a major global health burden, necessitating the development of novel and effective anti-TB drugs. Curcumin a naturally occurring compound found in turmeric has shown potential as an antimicrobial agent, including activity against Mycobacterium tuberculosis the causative agent of TB. In this computational study, the potential of natural derivatives of curcumin as anti-TB drugs was investigated using molecular docking studies and molecular dynamics (MD) simulations. Bedaquiline was used as the reference drug. Using Auto Dock 4.2, molecular docking studies were performed to predict the binding affinities and binding modes of a library of curcumin derivatives with the selected TB targets. The outcomes of the molecular docking studies showed that numerous curcumin derivatives have high affinity for the targeted proteins: Decaprenylphosphoryl-β-D-ribose oxidase protein, Dihydrofolate reductase protein, Enoyl- {acyl-carrier protein} reductase (NADH) protein, InhA 4,3-oxoacyl-(Acyl-carrierprotein) reductase protein, Pantothenatekinaseprotein, UDP-N-Acetylmuramoyl-L-Alanyl-DGlutamate-2,6 Diaminopimelateligase protein. Insights into prospective curcumin derivatives' modes of action as long-term control drugs were offered by the docking scores and interaction profiles. The key interactions influencing the binding process were also understood by investigation of the binding modes. The stability and dynamic behaviour of the chosen curcumin derivatives in complex with the TB targets were examined using MD simulations. These simulations allowed for the long-term study of conformational changes, flexibility, and stability of the derivatives of curcumin within the binding pockets of TB targets. Understanding the dynamic behaviour and interactions of the curcumin derivatives with TB targets was made possible by MD simulations. Root mean square deviation (RMSD) and root mean square fluctuation (RMSF) are two metrics used to assess stability. The results of the docking were supplemented by information from the MD simulations, providing a thorough insight into the binding modes and stability of the curcumin derivatives. By estimating binding affinities through the use of Auto Dock's advanced scoring methods, it was possible to calculate binding free energies and it revealed that all derivatives except one have good binding affinities with the studied proteins. It helped to reveal that the studied natural derivatives clarify the relative potency and selectivity of the derivatives for the tuberculosis targets. In conclusion, the computational findings of this study suggest that natural derivatives of curcumin hold promise as anti-TB drugs. These findings provide a basis for further experimental investigations and optimization of the identified curcumin derivatives as potential candidates for the development of novel anti-TB drugs.Item Ionic conductivity of novel solid polymer electrolyte based on polyethylene oxide (PEO) and magnesium pyrophosphate (Mg2P2O7)(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Lakshan, K. L. A. C.; Sumathipala, H. H.; Wijesundara, L. B. D. R. P.Lithium-ion batteries were hailed as a breakthrough solution for energy storage, revolutionizing portable electronics, electric vehicles, and other applications. However, as their implementation expanded, certain drawbacks came to light. Issues such as limited energy density, safety concerns, and the scarcity and high cost of lithium resources highlighted the need for a replacement. Researchers turned their attention to alternative materials, with sodium being a promising candidate due to its abundance. However, its high reactivity posed significant challenges. The search for a viable alternative led scientists to explore magnesium-based electrolytes. Lithium and magnesium are almost similar in ionic radii, presenting an exciting opportunity for further research. In this Investigation, the focus was on synthesizing and characterizing a novel magnesium ionbased solid polymer electrolyte. Polyethene oxide (PEO) was chosen as the polymer host, and magnesium pyrophosphate (Mg2P2O7) as the dopant salt. By varying the amount of salt while keeping the same amount of PEO, five different types of electrolytes were made: PEO5Mg2P2O7, PEO10Mg2P2O7, PEO15Mg2P2O7, PEO20Mg2P2O7, and PEO25Mg2P2O7. The hot-pressed technique was used to fabricate the solid polymer electrolytes, and the resulting materials were characterized in the frequency range of 1Hz to 1 MHz using the Gamry framework version 6.11. Arrhenius plots were derived from Nyquist plots to study the conductivity variation with temperature. The temperature range for the study spanned from 25°C to 100°C. The characterization results revealed that among the different electrolyte samples, PEO10Mg2P2O7 demonstrated the highest electrical conductivity of 5.0×10-6 Scm-1 at 50°C. This temperature was selected since the melting point of PEO is 64 °C. This value of conductivity is comparatively lower than most existing magnesium ion-based solid polymer electrolytes. The results from this study pave the way for further investigations and improvements. Incorporating fillers could enhance the conductivity of the electrolyte material and improve its overall performance. Such advancements may yield even more promising results, making magnesium-based solid polymer electrolytes viable candidates for solid-state batteries. Alternatively, a gel polymer might give a more promising result than a solid polymer.Item Impact of threshing, blanching, and drying on piperine content in “black pepper” (Piper nigrum L.)(Faculty of Science, University of Kelaniya Sri Lanka, 2023) Lakmali, H. M. R. P.; Liyanage, T.; Subasinghe, H. M. P. A.; Kirthisinghe, J. P.All spices exported from Sri Lanka are tropical aromatics used in human foods for flavoring. Among them, black pepper is valued for its distinct biting quality attributed to the alkaloid, piperine. The amount of piperine content can be influenced by alterations in conditions of the black pepper processing chain. Therefore, the study aimed to find the variation in piperine content in black pepper via the facilitation of different threshing methods and processing procedures in the black pepper processing chain. Three types of threshing methods (Hand threshing, foot threshing and machine threshing), two types of blanching (Blanching and without blanching) and two types of drying methods (Sun drying and mechanical drying) were used as treatments and the piperine content in black pepper was determined by spectrophotometrically. Piperine content was measured in triplicate samples after solar drying and mechanical drying. According to the results, there was no significant difference (p>0.5) in the threshing method for piperine content. However, the majority of the black pepper samples showed that there was a significant difference in piperine content in blanched samples than the un-blanched samples implying that the piperine percentage increases with the increase in blanching. Further, piperine content was significantly lower (p