Nisansa de Silva’s Research Group conducts research in natural language processing with a special focus on low-resource languages such as Sinhala and Tamil, data quality in multilingual corpora, and applied machine learning, based at the Department of Computer Science & Engineering, University of Moratuwa. The group was originally established in 2011, and went on semi-hiatus while Dr. de Silva was at the University of Oregon (2014–2020). It was formally re-established in 2021 upon his return to UoM.
Faculty and students explore multiple aspects of language technology, including lexical semantics, sentiment and subjectivity analysis, graph-based NLP, and multilingual text processing. Their work has appeared at major international venues such as ACL, EACL, WMT, and LoResMT, with ongoing collaborations bridging local linguistic challenges and global research frontiers.
The group has received research funding from Google and the University of Moratuwa, while also making an impact through the release of open-source tools, surveys, and models to support the wider Sinhala and Tamil NLP communities.
ActivePI: Nisansa de Silva
The proposed research is expected to break new ground by addressing the dual challenges of linguistic complexity and cultural awareness in Sinhala, a low-resource language largely overlooked in LLM research.
ActivePI: Nisansa de Silva
This project delves into the synergy between Natural Language Processing (NLP) and the legal domain, presenting novel solutions to enduring challenges.
ClosedPI: Dejing Dou
We propose to advance biomedical natural language processing by combining ontology-based reasoning, semantic search, and embedding-driven methods to improve information extraction, representation, and consistency detection in biomedical texts.
ActivePI: Nisansa de Silva
The Knowledge Representation project investigates methods for structuring, aligning, and reasoning over knowledge extracted from language, with particular emphasis on low-resource settings, domain-specific semantics, and intelligent information access.
ActivePI: Nisansa de Silva
This project aims to develop a comprehensive diachronic corpus for the Sinhala language, addressing the scarcity of historical linguistic resources for a language spoken by approximately 16 million people in Sri Lanka.
ActivePI: Nisansa de Silva
We propose to advance natural language processing for low-resource settings by leveraging data augmentation, transfer learning, and model adaptation techniques to overcome the scarcity of annotated data and linguistic resources.
Journal Papers
Krishan Chavinda, Pasan Kalansooriya, Thushalya Weerasuriya, Nisansa de Silva, Uthayasanker Thayasivam, Kogul Srikandabala, Kirishnni Prabagar, and Damminda Alahakoon, "An emotion aware context adaptive machine learning approach for detecting hate speech in social media", Neural Computing and Applications, vol. 38, no. 8, pp. 1433-3058, 2026. doi: 10.1007/s00521-026-12029-8
Conference Papers
Dhinanjaya Fernando, Dinura Ginige, Kalana Lakshan, Chanupa Gurusinghe, Lasana Pahanga, Subavarshana Arumugam, Sandeepa Weerasekara, Sandareka Wickramanayake, and Nisansa de Silva, "The Remittance Blueprint: Data-driven Intelligence for Sri Lanka", in 2026 Moratuwa Engineering Research Conference (MERCon), 2026, pp. 61-66. doi: 10.1109/MERCon71835.2026.11691526
Himath Dhanapala, Haren Daishika, Himandhi Kuruppu, Sithija Seneviratne, Ashini Kavindya, Patalee Narasinghe, Sandeepa Weerasekara, Nisansa de Silva, and Sandareka Wickramanayake, "Trilingual Topic Modeling of Sri Lankan Parliamentary Debates", in 2026 Moratuwa Engineering Research Conference (MERCon), 2026, pp. 389-394. doi: 10.1109/MERCon71835.2026.11691324
Tharusha Perera, Janith Mahanama, Maleesha Kumarasinghe, Bimsara Udurawana, Praveen Nawarathna, Patalee Narasinghe, Nathali Athukorala, Sandareka Wickramanayake, and Nisansa de Silva, "The Effect of Search Intent Data on Predicting Post-Crisis Daily Tourist Arrivals in Sri Lanka", in 2026 Moratuwa Engineering Research Conference (MERCon), 2026, pp. 395-400. doi: 10.1109/MERCon71835.2026.11691456
Ruzaini Ahmedh, Yohan Jayasinghe, Tharumini Gamage, Ifaz Ikram, Hasini Lawanya, Nirasha Munasinghe, Patalee Narasinghe, Nisansa de Silva, and Sandareka Wickramanayake, "Monsoon Mayhem to Market Waves: Forecasting Fisheries Resilience in Sri Lanka", in 2026 Moratuwa Engineering Research Conference (MERCon), 2026, pp. 401-406. doi: 10.1109/MERCon71835.2026.11691272
Anupama Wickramaratne, Thevindu Fernando, Tharupahan Jayawardana, Dehan Wijesinghe, Senindu Dinapura, Madara Mendis, Nevidu Jayatilleke, Nisansa de Silva, and Sandareka Wickramanayake, "Impact of Cyclone Ditwah on the Colombo Stock Exchange: An Event Study on Market Reactions to Natural Disasters", in 2026 Moratuwa Engineering Research Conference (MERCon), 2026, pp. 407-412. doi: 10.1109/MERCon71835.2026.11691317
Rahim Iqbal, Asfi Ahamed, Izzath Nisfer, Shazan Shaheed, Muhammadu Ilham, Nathali Athukorala, Madara Mendis, Nisansa de Silva, and Sandareka Wickramanayake, "Environmental Drivers of Respiratory Disease: A District Level Analysis", in 2026 Moratuwa Engineering Research Conference (MERCon), 2026, pp. 413-418. doi: 10.1109/MERCon71835.2026.11691342
Ranuga Weerasekara, Heshan Nethmina, Manuja Ranathunga, Vinma Wettasinghe, Dinithi Navodya, Subavarshana Arumugam, Nirasha Munasinghe, Nisansa de Silva, and Sandareka Wickramanayake, "When Prices Double in a Week: Forecasting of Agricultural Volatility in Import-Isolated Markets", in 2026 Moratuwa Engineering Research Conference (MERCon), 2026, pp. 419-424. doi: 10.1109/MERCon71835.2026.11691365 
Sonath Kirindage, Vihanga Nimsara, Sakindu Rajapaksa, Kavyanga Hathurusinghe, Lahiru Dilshan, Subavarshana Arumugam, Nathali Athukorala, Sandareka Wickramanayake, and Nisansa de Silva, "Golden Hour Divide: Trauma Care Accessibility and Resource Vulnerability in Sri Lanka", in 2026 Moratuwa Engineering Research Conference (MERCon), 2026, pp. 425-430. doi: 10.1109/MERCon71835.2026.11691402
Hesandi Mallawarachchi, Senilka Madurapperumage, Nadil Kulathunge, Thilokya Angeesa, Nethsith Gunaweera, Sandeepa Weerasekara, Patalee Narasinghe, Nisansa de Silva, and Sandareka Wickramanayake, "Forecasting Weather-Driven Price Dynamics Across Sri Lankan Tea Market Catalogues", in 2026 Moratuwa Engineering Research Conference (MERCon), 2026, pp. 431-436. doi: 10.1109/MERCon71835.2026.11691572
Dilusha Chandrasiri, Maneesha Herath, Yasith Hewarathna, Muditha Herath, Gishan Bandara, Madara Mendis, Nathali Athukorala, Nisansa de Silva, and Sandareka Wickramanayake, "How Environment and Urbanization Shape Bird Diversity in Sri Lanka", in 2026 Moratuwa Engineering Research Conference (MERCon), 2026, pp. 437-442. doi: 10.1109/MERCon71835.2026.11691486
Ramanaish Abaiyan, Ruththiragayan Sutharsan, Kusal Amantha, Anusan Krishnathas, Asma Rauff, Kovindarajah Sriyathurshan, Patalee Narasinghe, Nirasha Munasinghe, Nisansa de Silva, and Sandareka Wickramanayake, "Fault of Our Stars: Behavioral Drivers of Rating-Sentiment Incongruence", in 2026 Moratuwa Engineering Research Conference (MERCon), 2026, pp. 443-448. doi: 10.1109/MERCon71835.2026.11691426
Lakshani Galwatta, Nisansa de Silva, Sarangi Aththanayake, and Adithya Galwatta, "SalAngaBhava: A Sinhala Market Dataset for Aspect-based Sentiment Analysis", in 2026 Moratuwa Engineering Research Conference (MERCon), 2026, pp. 664-669. doi: 10.1109/MERCon71835.2026.11691353
Tharani Jayaratne and Nisansa de Silva, "Hybrid Genealogical Relationship Extraction from Wikipedia", in Applied Data Science \& Artificial Intelligence Conference, 2026.
Kaushal Kahapola, Sharada Galappaththi, Dinith Ranasinghe, Ridwan Shariffdeen, Nisansa de Silva, Srinath Perera, and Sandareka Wickramanayake, "JavaBackports: A Dataset for Benchmarking Automated Backporting in Java", in 23rd International Conference on Mining Software Repositories (MSR), 2026, pp. 712-716. doi: 10.1145/3793302.3793331
Mineth Weerasinghe, Himindu Kularathne, Methmini Madhushika, Danuka Lakshan, Nisansa de Silva, Adeesha Wijayasiri, and Srinath Perera, "From Monolith to Microservices: A Comparative Evaluation of Decomposition Frameworks", in Recent Trends and Challenges in Information Systems and Technologies, 2026, pp. 309--320. doi: 10.1007/978-3-032-32032-2_29
Rajith Arulanandam and Nisansa De Silva, "Section-Weighted Hybrid Approach for Legal Case Retrieval", in 2026 8th International Conference on Natural Language Processing (ICNLP), 2026, pp. 567--571. doi: 10.1109/ICNLP69856.2026.11527762
Nevidu Jayatilleke, Nisansa de Silva, Uthpala Nimanthi, Gagani Kulathilaka, Azra Safrullah, and Johan Sofalas, "SiDiaC-v. 2.0: Sinhala Diachronic Corpus Version 2.0", in Proceedings of the Fifteenth Language Resources and Evaluation Conference (LREC 2026), Palma, Mallorca, Spain: European Language Resources Association (ELRA), 05. 2026, pp. 6740--6763. doi: 10.63317/2ybff4o55vrq
K M Hewapathirana, Nisansa de Silva, and C D Athuraliya, "Adapter-Based Multi-Document Summarisation: Opinion Summarisation Use Case", in Proceedings of the 18th International Conference on Agents and Artificial Intelligence - Volume 4: ICAART, SciTePress, 2026, pp. 3018-3027. doi: 10.5220/0014349400004052 
Kavindu Warnakulasuriya, Prabhash Dissanayake, Navindu De Silva, Stephen Cranefield, Bastin Tony Roy Savarimuthu, Surangika Ranathunga, and Nisansa de Silva, "Evolution of Cooperation in LLM-Agent Societies: A Preliminary Study Using Different Punishment Strategies", in Coordination, Organizations, Institutions, Norms, and Ethics for Governance of Multi-Agent Systems XVIII, Springer Nature Switzerland, 2026, pp. 115--133. doi: 10.1007/978-3-032-17542-7_7
Workshop Papers
Ovindu Atukorala, Randeepa Appuhami, and Nisansa de Silva, "LawChain: A Resource-Efficient Blueprint for Legal Information Retrieval in Low-Resource Jurisdictions", in ICML 2026 GlobalSouthML, 2026.
Vishal Thenuwara, W M Yomal De Mel, and Nisansa De Silva, "Team VYN at SemEval-2026 Task 3: Dimensional Aspect-Based Sentiment Analysis", in Proceedings of the 20th International Workshop on Semantic Evaluation (2026), 2026, pp. 1755--1764. doi: 10.18653/v1/2026.semeval-1.223
Preprints
Mineth Weerasinghe, Himindu Kularathne, Methmini Madhushika, Danuka Lakshan, Nisansa de Silva, Adeesha Wijayasiri, and Srinath Perera, "TripleBound: Triplet-Guided Heterogeneous Graph Learning for Microservice Decomposition", arXiv preprint arXiv:2609.11212, 2026
Nevidu Jayatilleke and Nisansa de Silva, "Dynamics of meaning: Towards the Evaluation of Diachronic Semantic Change in Sinhala", arXiv preprint arXiv:2609.08609, 2026
Surangika Ranathunga, Nisansa de Silva, Aloka Fernando, Kavindu Warnakulasuriya, Isuru Wijesiri, Menan Velayuthan, Charitha Rathnayaka, Thivaharan Varatharajan, Sajeevi Silva, Piumi Kandanaarachchi, and Uthayasanker Thayasivam, "EnSiTa-A Trilingual Multi-Domain Parallel Dataset and Benchmark for Domain-Specific Machine Translation", ResearchGate, 2026
Thisen Ekanayake and Nisansa de Silva, "HelaBERT: Enhancing Sinhala Language Understanding with Dual Pooling Classification Head", arXiv preprint arXiv:2608.22922, 2026
Theekshana Samaradiwakara, Nisansa de Silva, and George C Lobb, "Semantics of Subterfuge: Benchmarking Legal Deception Detection Against General-domain State-of-the-Art", arXiv preprint arXiv:2607.29066, 2026
Nethmi Muthugala, Supryadi, Surangika Ranathunga, Nisansa de Silva, Ruijie Tao, Ovindu Gunatunga, Pengyun Zhu, Shaowei Zhang, Jingting Zheng, and Deyi Xiong, "LKValues: Aligning Large Language Models with Sri Lankan Societal Values", arXiv preprint arXiv:2607.20410, 2026
Nisansa de Silva and Surangika Ranathunga, "Sinhala Physical Common Sense Reasoning Dataset for Global PIQA", arXiv preprint arXiv:2602.02207, 2026. doi: 10.48550/arXiv.2602.02207
