Chamaka Karunanayake

Mr. Chamaka Karunanayake

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Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 June 2024 in Water Conservation Science and Engineering
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KTKiran Tota-Maharaj
Kiran Tota-Maharaj
CKChamaka Karunanayake
Chamaka Karunanayake
KKKushmita Kunwar
Kushmita Kunwar
ACAaron Anil Chadee
Aaron Anil Chadee
Hazi Mohammad AzamathullaHazi Mohammad Azamathulla
Hazi Mohammad Azamathulla
Upaka RathnayakeUpaka Rathnayake
Upaka Rathnayake

17 October 2020 in Mathematical Problems in Engineering
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Journal Article
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BKBhabishya Khaniya
Bhabishya Khaniya
CKChamaka Karunanayake
Chamaka Karunanayake
MGMiyuru Gunathilake
Miyuru Gunathilake
Upaka RathnayakeUpaka Rathnayake
Upaka Rathnayake
The projection of future hydropower generation is extremely important for the sustainable development of any country, which utilizes hydropower as one of the major sources of energy to plan the country’s power management system. Hydropower generation, on the other hand, is mostly dependent on the weather and climate dynamics of the local area. In this paper, we aim to study the impact of climate change on the future performance of the Samanalawewa hydropower plant located in Sri Lanka using artificial neural networks (ANNs). ANNs are one of the most effective machine learning tools for examining nonlinear relationships between the variables to understand complex hydrological processes. Validated ANN model is used to project the future power generation from 2020 to 2050 using future projected rainfall data extracted from regional climate models. Results showcased that the forecasted hydropower would increase in significant percentages (7.29% and 10.22%) for the two tested climatic scenarios (RCP4.5 and RCP8.5). Therefore, this analysis showcases the capability of ANN in projecting nonstationary patterns of power generation from hydropower plants. The projected results are of utmost importance to stakeholders to manage reservoir operations while maximizing the productivity of the impounded water and thus, maximizing economic growth as well as social benefits.

30 November 2020 in Applied Computational Intelligence and Soft Computing
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CKChamaka Karunanayake
Chamaka Karunanayake
MGMiyuru Gunathilake
Miyuru Gunathilake
Upaka RathnayakeUpaka Rathnayake
Upaka Rathnayake
Prediction of water resources for future years takes much attention from the water resources planners and relevant authorities. However, traditional computational models like hydrologic models need many data about the catchment itself. Sometimes these important data on catchments are not available due to many reasons. Therefore, artificial neural networks (ANNs) are useful soft computing tools in predicting real-world scenarios, such as forecasting future water availability from a catchment, in the absence of intensive data, which are required for modeling practices in the context of hydrology. These ANNs are capable of building relationships to nonlinear real-world problems using available data and then to use that built relationship to forecast future needs. Even though Sri Lanka has an extensive usage of water resources for many activities, including drinking water supply, irrigation, hydropower development, navigation, and many other recreational purposes, forecasting studies for water resources are not being carried out. Therefore, there is a significant gap in forecasting water availability and water needs in the context of Sri Lanka. Thus, this paper presents an artificial neural network model to forecast the inflows of one of the most important reservoirs in northern Sri Lanka using the upstream catchment’s rainfall. Future rainfall data are extracted using regional climate models for the years 2021–2050 and the inflows of the reservoir are forecasted using the validated neural network model. Several training algorithms including Levenberg–Marquardt (LM), BFGS quasi-Newton (BFG), scaled conjugate gradient (SCG) have been used to find the best fitting training algorithm to the prediction process of the inflows against the measured inflows. Results revealed that the LM training algorithm outperforms the other tests algorithm in developing the prediction model. In addition, the forecasted results using the projected climate scenarios clearly showcase the benefit of using the forecasting model in solving future water resource management to avoid or to minimize future water scarcity. Therefore, the validated model can effectively be used for proper planning of the proposed drinking water supply scheme to the nearby urban city, Jaffna in northern Sri Lanka.

15 May 2024 in Agricultural Research
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HJHiggoda K. Janani
Higgoda K. Janani
CKChamaka Karunanayake
Chamaka Karunanayake
MGMiyuru Gunathilake
Miyuru Gunathilake
Upaka RathnayakeUpaka Rathnayake
Upaka Rathnayake
Climate change stands as one of the most pressing challenges confronting global ecosystems and human livelihoods. The agriculture sector of Anuradhapura district, Sri Lanka, well renowned for its pivotal role in the nation’s food production, faces an increasing threat from the changing climate. This study aims to incorporate the indicator system method which uses a set of indicators to assess the agricultural vulnerability (AV) to climate change in Anuradhapura district. The AV assessment used in this study involves three principal components exposure, sensitivity, and adaptive capacity. The indicators are normalized to allow spatial analysis and smooth integration within a geographic information system (GIS) framework. The AV of Anuradhapura district ranged from 0.32 to 0.67 and was divided among five levels very low, low, moderate, high, and very high. The findings suggest that Anuradhapura’s agricultural sector was significantly impacted by climate change as the majority of the total area was found to have very high, high, and moderate levels of AV with 25, 28, and 24%, respectively. The results obtained from this study are essential for formulating plans to improve Anuradhapura’s agricultural sector resilience and adaptability to ensure food security and livelihood sustainability considering the ever-changing climate.

7 September 2024 in Chemical Engineering Research and Design
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Journal Article
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KTKiran Tota-Maharaj
Kiran Tota-Maharaj
CKChamaka Karunanayake
Chamaka Karunanayake
DCDenver Cheddie
Denver Cheddie
HAHazi Md. Azamathulla
Hazi Md. Azamathulla
Upaka RathnayakeUpaka Rathnayake
Upaka Rathnayake

4 August 2022 in Preprints.org
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DTDan Tran-Thanh
Dan Tran-Thanh
YFYrle Greco Frank
Yrle Greco Frank
CKChamaka Karunanayake
Chamaka Karunanayake
Kavinda GunasekaraKavinda Gunasekara
Kavinda Gunasekara
DSDubey Sangita
Dubey Sangita
HMHazarika Kumar Manzul
Hazarika Kumar Manzul
Over the last few years, Earth Observation (EO) data has shifted towards increased use to produce official statistics, particularly in the agriculture sector. National statistics offices worldwide, including in Asia and the Pacific, are expanding their use of EO data to produce agricultural statistics such as crop classification, yield estimation, irrigation mapping, and crop loss estimation. The advances in image classification, such as pixel-based and phenology-based classifications, and machine learning create new opportunities for researchers to analyze EO data applied to agriculture statistics. However, it requires the ground truth (GT) data because classification result mainly depends on the quality of GT. Therefore, in this study, we introduced a random sampling approach to design and collect GT data using EO imagery and ancillary data. As a result of data collection, GT data improve the algorithms and validates classification results. Nevertheless, despite the importance of GT data, they are rarely disseminated as a data product in themselves. Thus, this results in an untapped opportunity to share GT data as a global public good, and improved use of survey and census data as a source of GT data.