Browsing by Author "Samarakoon, U"

Now showing 1 - 12 of 12

Embargo
CertiMart: Use Computer Vision to Digitize and Automate Supermarket with Fruit Quality Measuring and Maintaining
(IEEE, 2022-12-09) Rathnayake, W.P.D.N. P; Geeth Dulanjana, D; Punchihewa, A.V.B.W. G; Anjana, N.W. G; Suriya Kumari, P. K.; Samarakoon, U
Sri Lanka has a tropical environment, which makes it easy for fruit and vegetable plants to thrive. Vitamins, proteins, and other nutrients are abundant in fruits. However, there is a time when the fruit is considered to be fresh. During this time, many fruit supplier firms continue to supply fruit that is unsafe for ingestion due to inaccuracy in the sorting process when the fruit is taken from the plantation and the introduction of other fruit into an incorrect packing. As a result, detecting food rotting from the point of production to the point of consumption is critical. Inside the market we realize that there is unavailability of sorting of fruits. Just after receiving the fruit into the supermarket, we should have a way to measure freshness of fruit and maintain it. In addition to this ripened method identification and disease identification will be great help to this help.
Embargo
CodeJr: Comprehensive Programming Application for Children
(IEEE, 2022-12-09) Muthuthanthirige, M.D.C. J; Illangasinghe, U.P; Illangasinghe, D.N; Halgaswatta, I.; Samarakoon, U; Amarasena, N
Since the beginning of the millennium, computer technology has been the key area of concern and developing essential programming knowledge and intellectual skills from the young age have proven that they will gain more success in their careers. The ideology behind this research is, the problem with absence of a complete multi-disciplinary and interactive programming application for children between the age of 10 - 15 years, to learn programming concepts with a well-established text-based programming language. There are 4 major approaches in this research. Gamification approach focuses on expressing knowledge about Python programming via a game while concentrating on low perfumers. Collaborative approach aims to deliver a brand-new experience for children by aggregating cooperative methodologies and Artificial Intelligence with learning to enforce mutual learning. This component is based on collaborative sessions which allow a group of students with similar interest to join to learn python programming. Drag-drop approach enables children to learn Python language through videos and will be given basic practice questions after finishing the course. Story telling approach guides children to learn programming concepts step by step using story telling. Focused on storytelling approach and interactivity via voice conversation to learn programming language for children.
Open Access
Efficient photocatalysis of Cu doped TiO2/g-C3N4 for the photodegradation of methylene blue
(Elsevier, 2023-03-06) Liyanaarachchi, H; Thambiliyagodage, C; Liyanaarachchi, C; Samarakoon, U
The release of dyes into normal water reservoirs has become a tremendous environmental problem and the development of methods to remove such dyes is essential. A novel photocatalyst was fabricated in which Cu doped to TiO2 was coupled with g-C3N4 (Cu-TiO2/g-C3N4) in different weight percentages as 10, 30 and 50%, hydrothermally. Pure TiO2 consisted of both Anatase and Rutile phases where slight lattice distortions were observed in the Cu-doped TiO2 as evidenced by the XRD and Raman analysis. Cu was present at 1.7% by weight respective to TiO2 according to the XRF analysis. Spherical and irregularly shaped aggregated Cu-doped TiO2 nanoparticles in the range of 15–55 nm were heterogeneously distributed on the g-C3N4 matrix as observed by TEM and SEM. The band gap of TiO2 (3.0 eV) was reduced to 2.67 upon doping with Cu. The band gap of g-C3N4 was found to be 2.81 eV and that of Cu-TiO2/g-C3N4 in different weight percentages were in the range of 2.82 to 2.88 eV. Synthesized photocatalysts were tested on the ability to degrade methylene blue under UV and Visible light. Cu-TiO2/50% g-C3N4 showed the highest rate constant (4.4 × 10-3 min−1) which is 5 and 9.8 times greater than TiO2 and g-C3N4, respectively. The rate constant decreased with the introduction of EDTA and Isopropyl alcohol as they scavenge holes and hydroxyl radicals, respectively. The photocatalytic activity of all the nanomaterials increased with the increasing concentration of persulfate due to the increasing concentration of SO4●- and OH● produced. Synthesized nanomaterials effectively adsorb methylene blue under dark conditions following the pseudo-second-order kinetics suggesting that methylene blue molecules were chemisorbed to the adsorbents. The adsorption rate constant resulting in the best-performing photocatalyst was 0.122 g mg−1 min−1. Hence, it is evident that Cu-TiO2/g-C3N4 can effectively degrade methylene blue.
Embargo
Evaluating Teaching Content and Assessments based on Learning Outcomes
(IEEE, 2020-12-10) Pallegama, P. M. O. N; Kumari, K. A. M. R; Dissanayaka, D. M. D. P. M; Ravihansi, A. V. Y; Karunasenna, A; Samarakoon, U
A modularized syllabus content assigned to different units of a subject proves very useful to both teachings as well as the student community. In each module, learning outcomes are defined. In each learning outcome, lesson learning outcomes are defined. When the Teaching Content (Lecture content), Learning activities (Labs sheets and Tutorials), Final Question Papers are being made the subject learning outcome should be considered and it should be made within the subject learning outcomes. Then the teaching and learning process will be done properly. Nowadays Revised Bloom's Taxonomy standard is used to structure the Teaching Content, Learning Activities, and Final Question paper of a course in the best way. Currently, there is no proper solution to corporate above areas according to the Revised Bloom's Taxonomy. This paper discusses an automated system that provides the features to verify the module and lesson learning outcomes and their levels according to Revised Bloom's taxonomy and to verify that the teaching content and learning activities are within the learning outcomes. Beyond that, this system uses various technologies and algorithms to improve the accuracy and efficiency of this research. This automated system is able to achieve to the final outcome with the best accuracy and efficiency than the manual process.
Open Access
Fe3O4 Chitosan Nanocomposite as a pH-Responsive Delivery System for Enhanced Delivery of Punica Granatum L. Polyphenols
(American Chemical Society, 2025-10-17) Rukshan, R; Rajapaksha, N; Wijayawardana, S; Thambiliyagodage, C; Senevirathne, U; Jayanetti, M; Samarakoon, U
Punica granatum extract (PG), consisting of punicalagin, ellagic acid, and gallic acid, was loaded onto an Fe3O4/Chitosan (Fe3O4@Chi) nanocomposite (Fe3O4@Chi-PG) to enhance pharmacokinetic properties. Fe3O4was synthesized via the coprecipitation method and coupled with chitosan in 2% acetic acid solution via glutaraldehyde cross-linking. The presence of interested polyphenols in the pomegranate extract was confirmed by HPLC analysis, and the extract was post-loaded to the nanocarrier. XRD confirmed the crystallographic orientation of the nanocarrier, and SEM analysis confirmed the successful coupling of Fe3O4onto the chitosan surface during the fabrication of Fe3O4@Chi. BET surface area analysis revealed the presence of micro- and mesopores in the synthesized materials. Significant reduction of the BET surface area and the pore volume of Fe3O4@Chi-PG compared to Fe3O4@Chi suggested the loading of the porous network and surface by PG. The presence of vibrational bands corresponding to the functional groups of the relevant bioactive compounds was confirmed via FT-IR analysis. The IC50values of the nanocomposite for DPPH and egg albumin denaturation assays were 18.69 and 257.69 μg/mL, respectively. The PG encapsulation efficiency of Fe3O4@Chi-PG was reported to be 86.44%. The pH-responsive release of the polyphenols was studied by fitting the release data into five kinetic models, including Korsemeyer–Peppas (KP) and Peppas–Sahlin (PS). The KP and PS models were selected to interpret the release mechanism based on the R2≥ 0.95 value. A combination of Fickian diffusion, relaxation, and swelling dominates the polyphenol release. Quasi-Fickian diffusion is responsible for the release in media with pH 1–6.7, whereas anomalous transport occurs at pH 7.4 (n = 0.46) according to the KP model. Polymer relaxation is the dominant mechanism for the release of bioactive compounds at pH 7.4, as exhibited by R/F > 1. However, the contribution of relaxation to the release of polyphenols at pH 2.5, 4, and 5.5 was negligible according to the parameters (kR= 0). Characteristics of chitosan, including protonation and deprotonation of NH2groups, surface charge of Fe3O4, ionization of COOH and OH groups of the polyphenols, and molecular weight of the active compounds, contributed to the differences in the release behavior.
Embargo
Know More: Social Media based Student Centric E-learning platform with Machine Learning Approaches
(IEEE, 2022-07-18) Malavige, O; Nasome, V; Costa, M; Jayasinghe, B; Karunasena, A; Samarakoon, U
Social media has become increasingly popular among the younger generation in the last decade. Students engage with social media on daily basis, and it affects their interests, lifestyle, and attitude. There are many existing e-learning applications used by higher educational institutes, but such applications are mainly focused on delivering teaching content rather than facilitating active and interactive learning. This paper proposes a novel e-learning platform to create an active and interactive learning environment for students leveraging social media strategies, especially those of “Facebook.” The objective of this platform is to promote self-motivation, self-learning, and interaction. The platform features were built on considering three aspects important for learning, which are personal knowledge management, learning management, and collaborative learning. Features of the proposed platform that it comprises are Newsfeed, Classmates, Profile, Cluster, Repository, Knowledgebase, Bookmark, Topic Map, Search Engine, Test Mark Prediction, and Slide Show Summary generator. Machine Learning techniques and Natural Language Processing were used to build some of the platform features. The feedback collected on the proposed system, “KnowMore,” shows that the satisfaction of the students has increased with the system.
Open Access
LEXISGURU: Mobile Application for Learning Basic Lexis in English for Kids
(Springer Science and Business Media Deutschland GmbH, 2021-11-05) Jayasinghe, M. J. W; Hennayaka, W. H. M. A. D. H; Fernando, M. P. M; Thilakarathne, K. N. U; Samarakoon, U; Kumari, S
Lexis is an essential part of English vocabulary that puts a good foundation on a child’s English knowledge. In this rapidly globalizing world, it is fundamentally essential to learn English from a young age. In recent years eLearning, mobile applications have been developed for teaching Lexis to children. The market of educational mobile apps, especially for English language learning, has been rapidly growing. Especially in a country like Sri Lanka, English is not the mother tongue, it is the second language. So, when that second language is not taught right the child will lose interest in learning that language. The problem is that the existing lexical learning mobile applications does not aim at keeping the child interested and interactive in the learning process and in Sri Lanka, children find it difficult to understand these lexical parts. As a result, teachers and parents had to spend a lot of time to teach them those lexical parts. We designed and developed a mobile application called “LexisGuru” that uses interactive and effective ways to teach three lexical parts that are homophones, synonyms, and antonyms to children aged between 8–10 in Sri Lanka. This mobile application uses Machine Learning (ML), Image Processing (IP), gamification that includes collaborative environments, and speech recognition techniques. The developed mobile application was introduced to primary level learners, and they were all very attracted and interested while using this application. The attractive user interfaces, the pretests, and posttests, notifying the child when he loses focus while learning, using interesting stories and activities to teach lexis, playing a game with multiple players, and asking questions from the lesson and taking the voice inputs gave a new experience and showed that making the mobile application interactive as possible is an effective way to teach lexis to children.
Embargo
Peer Learning – An Interactive and Collaborative E-Learning Application for College Students
(IEEE, 2022-12-26) Sirithunga, H. A. P. M.; Deshan, B. G. S; Sigera, P. H. D; Udagedara, P.Y; Samarakoon, U; Kumari, S
Since the start of the COVID-19 epidemic in 2020, the entire educational system has been challenging and Sri Lanka economic crisis, but this is especially effect for students who are now enrolled. This developmental milestone is reached when adolescents begin to assume responsibilities and acquire leadership skills through participation in a range of team activities. It is easiest to gain experience working in a group setting while still in school. Nevertheless, given the current stage of the Sri Lanka economic crisis, students will face a range of challenges. They are incapable of participating in group activities that are relevant to the subjects they teach, and, as previously indicated, enhancing their leadership skills, which is particularly problematic when working with students. The “Peer Learning” solution is a web-based application that supports students in enhancing their collaborative learning skills. Through the system, students have the opportunity to study a variety of collaborative tasks, which improves their educational and interpersonal abilities. In addition, professors can share their knowledge with students by personalizing questions, posting films, and demonstrating figures. Students can easily comprehend the system’s operation due to its user-friendly design, which enables advanced technological methods for monitoring and guiding students’ activities simultaneously.
Open Access
Persulfate assisted photocatalytic and antibacterial activity of TiO2–CuO coupled with graphene oxide and reduced graphene oxide
(https://www.nature.com, 2024-05-31) Thambiliyagodage, C; Liyanaarachchi, H; Jayanetti, M; Ekanayake, G; Mendis, A; Samarakoon, U; Vigneswaran, S
Photocatalysts of TiO2–CuO coupled with 30% graphene oxide (GO) were hydrothermally fabricated, which varied the TiO2 to CuO weight ratios to 1:4, 1:2, 1:1, 2:1 and 4:1 and reduced to form TiO2–CuO/reduced graphene oxide (rGO) photocatalysts. They were characterized using XRD, TEM, SEM, XPS, Raman, and DRS technologies. TiO2–CuO composites and TiO2–CuO/GO degrade methylene blue when persulfate ions are present. Persulfate concentration ranged from 1, 2, 4 to 8 mmol/dm−3 in which the highest activity of 4.4 × 10–2 and 7.35 × 10–2 min−1 was obtained with 4 mmol/dm−3 for TiO2–CuO (1:4) and TiO2–CuO/GO (1:1), respectively. The presence of EDTA and isopropyl alcohol reduced the photodegradation. TiO2–CuO coupled with rGO coagulates methylene blue in the presence of persulfate ions and such coagulation is independent of light. The catalyst dosage and the concentration of the dye were varied for the best-performing samples. The antibacterial activity of the synthesized samples was evaluated against the growth of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumonia. Ti:Cu (1:2)-GO and Ti:Cu (1:4)-GO had the highest antibacterial activity against K. pneumoniae (16.08 ± 0.14 mm), P. aeruginosa (22.33 ± 0.58 mm), E. coli (16.17 ± 0.29 mm) and S. aureus (16.08 ± 0.88).
Embargo
Project Zone : An Advanced Undergraduate Project Management System For Software Development
(IEEE, 2021-12-02) Amarasekara, T. N. E.; Isurindi, H. G. P.; Gamage, O. M.; Navanjana, E. H. D. T. D.; Samarakoon, U; Archchana, K
Project Management System important in largescale projects. There are existing project management tools such as Redmine, Microsoft Project, Jira. Most of the existing project management systems only configured for general purposes such as Project Management, Task management, Time line management. None of them capable of generating project groups, track student progress or track client meetings. These functions are very helpful in tracking project progress as well as individual member progress. Hence, the purpose of this research is to introduce set of new features to a project management system with accurate and effective project management capabilities. This system is capable of generating project groups using student’s skills, Grade point average (GPA). Smart project tracking system where it uses project repositories and system generated timeline for the project. Using the project tracking system, Supervisors can manage groups remotely. Automatic peer review also added to identify each student’s contribution to the project and finally a client portal where clients can request solutions for their requirements and students can use them as their module project. Client meetings will be tracked using voice-to-text algorithm and also emotional recognition where it will identify client’s satisfaction. All These system modules will be used to calculate group performance.
Open Access
Say No to Free Riding: Student Perspective on Mechanisms to Reduce Social Loafing in Group Projects.
(Science and Technology Publications, 2021) Samarakoon, U; Imbulpitiya, A; Manathunga, K
Project based learning is a popular teaching method in Information Technology undergraduate programs where students gain necessary skills and knowledge via a hands-on capstone project. Key learning gains from such projects are problem-solving skills by applying theoretical knowledge while improving soft skills like collaboration and communication. Students can improve critical thinking, learn to face challenging situations, and build creative solutions for a desired problem as a group. Irrespective of all these benefits, social loafing or simply free riding can be recognized as the key challenge in these group-based projects. Some students in group projects put less effort on group work than when they work alone while surviving in the group and taking credits for someone else’s work. This scenario leads to demotivation of hard-working members and lot of group conflicts. Ultimately, social loafing affects the group performance while resulting with unsuccessful projects and dissatisfied students. Seeking mechanisms for reducing social loafing in group projects is becoming a vital and this research proposes set of mechanisms to reduce social loafing in IT group projects and presents the students’ perspective on usefulness of each mechanism.
Open Access
The photocatalytic and antibacterial activity of graphene oxide coupled CoOx /MnOx nanocomposites
(Elsevier B.V., 2025-02) Liyanaarachchi, H; Thambiliyagodage, C; Jayanetti, M; Ekanayake, G; Wijayawardana, S; Samarakoon, U
CoOx and MnOx metal oxide composites were fabricated via co-precipitation varying the Co:Mn (CM) weight ratio as 4:1, 2:1, 1:1, 1:2 and 1:4, and they hydrothermally coupled with 30 wt% of graphene oxide (GO). XRD analysis revealed the presence of Co3O4 and CoO, and Mn2O3 and Mn3O4 phases in pure CoOx and MnOx metal oxides, respectively. The irregularly shaped metal oxide nanocomposites comprised Co3O4, Mn2O3 and Mn3O4 phases and were immobilized on GO. The band gap values of the composites varied in the range of 1.86 – 2.22 eV. The highest photocatalytic activity with a rate constant of 3.5 × 10−3 min−1 was obtained with CMG (1:4). The total removal of MB increased by 55.8 % when CM (1:4) were coupled with GO. The rate of photocatalysis was dramatically increased in the presence of S2O82- and was decreased in the presence of EDTA and isopropyl alcohol. The effect of catalyst dosage was determined by varying the weight to 25, 50, 75, and 100 mg, and the dye concentration was varied in the range of 25, 50, 75 and 100 mg/L. The presence of Pb2+ and Rhodamine B decreased the photocatalytic activity, while it remained the same in the presence of Cl- and PO43- as co-pollutants. The photocatalytic activity of CMG (1:4) was reduced to 72 % upon using the catalyst for five cycles. All the synthesized nanocomposites exhibited greater sensitivity to the Gram-positive strain than the Gram-negative strains.