2021 Moratuwa Engineering Research Conference (MERCon)最新文献

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Modeling and Simulation of Micro Size Ultrasonic Characteristics of Lead Zirconate Titanate and Polyvinylidene Fluoride 锆钛酸铅和聚偏氟乙烯微尺度超声特性建模与仿真
2021 Moratuwa Engineering Research Conference (MERCon) Pub Date : 2021-07-27 DOI: 10.1109/MERCon52712.2021.9525741
Parthipan Rajendraseelan, Thasankithan Vijayasingam, Upali Adikary
{"title":"Modeling and Simulation of Micro Size Ultrasonic Characteristics of Lead Zirconate Titanate and Polyvinylidene Fluoride","authors":"Parthipan Rajendraseelan, Thasankithan Vijayasingam, Upali Adikary","doi":"10.1109/MERCon52712.2021.9525741","DOIUrl":"https://doi.org/10.1109/MERCon52712.2021.9525741","url":null,"abstract":"This study was focused on modeling and simulation of micro size ultrasonic generator and receiver of polyvinylidene fluoride (PVDF) and lead zirconate titanate (PZT) using finite element analysis (FEA). When PZT-5 H was selected as both ultrasonic generator and receiver, the resonance frequency of the generator and receiver were determined as 15 MHz and 13 MHz respectively and the simulation was performed at 13 MHz frequency to generate ultrasonic wave. In addition to that, when PVDF was utilized as the receiver material its resonance frequency was determined as 10 MHz and therefore simulation was performed at 10 MHz. The resonance frequency remains the same (5 MHz) When PVDF was selected as an ultrasonic generator with whatever receiver materials (PVDF and PZT-5H) used. Then the generated ultrasonic wave was directed to hit the ultrasonic receiver to generate electric potential. To compare and validate the induced voltage across the receiver mathematical equation was derived using piezoelectric constitutive equations. When PVDF worked as receiver it generated higher voltage value than PZT-5H. On the other hand, when PZT-5H worked as an ultrasonic generator, it induced higher voltage across the receiver.","PeriodicalId":6855,"journal":{"name":"2021 Moratuwa Engineering Research Conference (MERCon)","volume":"95 1","pages":"31-36"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74493742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Water Resources Availability and Low Flow Discharge Analysis of Kelani River Basin in Wet Zone under Changing Climate Conditions 气候变化条件下湿区克拉尼河流域水资源有效性及低流量流量分析
2021 Moratuwa Engineering Research Conference (MERCon) Pub Date : 2021-07-27 DOI: 10.1109/MERCon52712.2021.9525721
Chamika Punsara, Lalith Rajapakse
{"title":"Water Resources Availability and Low Flow Discharge Analysis of Kelani River Basin in Wet Zone under Changing Climate Conditions","authors":"Chamika Punsara, Lalith Rajapakse","doi":"10.1109/MERCon52712.2021.9525721","DOIUrl":"https://doi.org/10.1109/MERCon52712.2021.9525721","url":null,"abstract":"This study estimates the effects of climate change on water resources availability and low flow streamflow discharge in the wet zone Kelani Basin in Sri Lanka. The selected pilot areas for this study are the Norwood subbasin and the Deraniyagala subbasin of Kelani river. This research further evaluates the future change in streamflow of Kelani river due to climate change using the synthetic climate scenario analysis. Standard Precipitation Index (SPI) analysis was performed to identify meteorological drought conditions that appeared in the study area. HEC-HMS rainfall-runoff was used to simulate streamflow, due to the accessibility, reliability, and flexibility of the model. The model results indicated that the capability of HEC-HMS to simulate streamflow in the basin with reasonably higher accuracy. According to the rainfall elasticity of streamflow analysis, elasticity values of 0.75 and 1.00 were obtained for the Norwood and Deraniyagala subbasins, which indicate that a 1.00% change in rainfall results in a 0.75% and 1.00% change in streamflow discharge in two basins, respectively. For the testing of future water management plans and policymaking on low flow management, this model is a feasible tool while the findings and outcome of the research will be useful for scenario analysis and implementation.","PeriodicalId":6855,"journal":{"name":"2021 Moratuwa Engineering Research Conference (MERCon)","volume":"36 1","pages":"516-521"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84340797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Improving Back-Translation with Iterative Filtering and Data Selection for Sinhala-English NMT 用迭代滤波和数据选择改进僧伽罗语-英语NMT的反翻译
2021 Moratuwa Engineering Research Conference (MERCon) Pub Date : 2021-07-27 DOI: 10.1109/MERCon52712.2021.9525800
Koshiya Epaliyana, Surangika Ranathunga, Sanath Jayasena
{"title":"Improving Back-Translation with Iterative Filtering and Data Selection for Sinhala-English NMT","authors":"Koshiya Epaliyana, Surangika Ranathunga, Sanath Jayasena","doi":"10.1109/MERCon52712.2021.9525800","DOIUrl":"https://doi.org/10.1109/MERCon52712.2021.9525800","url":null,"abstract":"Neural Machine Translation (NMT) requires a large amount of parallel data to achieve reasonable results. For low resource settings such as Sinhala-English where parallel data is scarce, NMT tends to give sub-optimal results. This is severe when the translation is domain-specific. One solution for the data scarcity problem is data augmentation. To augment the parallel data for low resource language pairs, commonly available large monolingual corpora can be used. A popular data augmentation technique is Back-Translation (BT). Over the years, there have been many techniques to improve Vanilla BT. Prominent ones are Iterative BT, Filtering, and Data selection. We employ these in Sinhala - English extremely low resource domain-specific translation in order to improve the performance of NMT. In particular, we move forward from previous research and show that by combining these different techniques, an even better result can be obtained. Our combined model provided a +3.0 BLEU score gain over the Vanilla NMT model and a +1.93 BLEU score gain over the Vanilla BT model for Sinhala → English translation. Furthermore, a +0.65 BLEU score gain over the Vanilla NMT model and a +2.22 BLEU score gain over the Vanilla BT model were observed for English → Sinhala translation.","PeriodicalId":6855,"journal":{"name":"2021 Moratuwa Engineering Research Conference (MERCon)","volume":"30 1","pages":"438-443"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85439250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 4
iGrasp Hand: A Biomimetic Transradial Robotic Hand Prosthesis with a Clutching Mechanism 具有抓握机制的仿生跨径向机械手
2021 Moratuwa Engineering Research Conference (MERCon) Pub Date : 2021-07-27 DOI: 10.1109/MERCon52712.2021.9525767
N. Dasanayake, P. Viduranga, U. Perera, S.A.P.K. Siyambalagoda, T. Cooray, K.R.T. Fernando, R. Ranaweera, R. Gopura
{"title":"iGrasp Hand: A Biomimetic Transradial Robotic Hand Prosthesis with a Clutching Mechanism","authors":"N. Dasanayake, P. Viduranga, U. Perera, S.A.P.K. Siyambalagoda, T. Cooray, K.R.T. Fernando, R. Ranaweera, R. Gopura","doi":"10.1109/MERCon52712.2021.9525767","DOIUrl":"https://doi.org/10.1109/MERCon52712.2021.9525767","url":null,"abstract":"This paper proposes a nineteen degrees of freedom transradial robotic hand prosthesis, named iGrasp Hand. The device consists of three units: clutching unit, wrist unit and hand unit. Fingers of the iGrasp Hand are actuated by six motors, coupled to an under-actuated tendon-based mechanism. A novel clutching mechanism, installed with one-way bearings, is introduced to achieve passive isometric contraction of fingers during grasps. Palmar arching is facilitated by the addition of carpometacarpal joints in the ring and little fingers. A mathematical model is formulated to analyse finger motion and a prototype is fabricated for experimental testing. Moreover, a position control algorithm is implemented to achieve targeted grasping patterns. Several experiments were carried out to evaluate the effectiveness of the device. The results reveal the capability of iGrasp Hand in achieving twelve grasping patterns, ranging from power to precision grasps. The palmar arching and opposition/re position movement of the thumb allows the grasping of smaller objects. Furthermore, the potential for reducing energy consumption during the isometric hold was investigated. The iGrasp Hand can perform over 70% of activities-of-daily-Iiving and mimic the human hand with an anthropomorphism mobility index of 40%.","PeriodicalId":6855,"journal":{"name":"2021 Moratuwa Engineering Research Conference (MERCon)","volume":"17 1","pages":"190-195"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82530595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Water Resources Availability and Low Flow Discharge Analysis of Two Selected River Basins in the Dry Zone Under Changing Climate Conditions 气候变化条件下干旱区两大流域水资源可利用性与低流量分析
2021 Moratuwa Engineering Research Conference (MERCon) Pub Date : 2021-07-27 DOI: 10.1109/MERCon52712.2021.9525654
Buveenthiran Mahenthiran, Lalith Rajapakse
{"title":"Water Resources Availability and Low Flow Discharge Analysis of Two Selected River Basins in the Dry Zone Under Changing Climate Conditions","authors":"Buveenthiran Mahenthiran, Lalith Rajapakse","doi":"10.1109/MERCon52712.2021.9525654","DOIUrl":"https://doi.org/10.1109/MERCon52712.2021.9525654","url":null,"abstract":"Climate change is the most significant challenge to achieving sustainable development and it is one of the most discussed topics today due to the frequent changes triggered around the globe because of both manmade and natural causes. Water resources and river flow are the main hydrologic parameters often affected by climate change. In the present study, the predicted climate change variations are derived from literature and HEC-HMS rainfall-runoff model is used to investigate impending impacts on using two dry zone basins. For Kirindi Oya and Maduru Oya basins, the model was calibrated using a data period from 2001/2-2008 and validated from 2009–2015. The MRAE (Mean Ratio Absolute Error), NSE (Nash-Sutcliffe Efficiency), R2 (Coefficient of Determination) and PBIAS (Percentage of BIAS) were used as objective functions. Even though the main study area is the dry zone of Sri Lanka, the analysis included the other climatic zones, mainly the wet zone as well, as they have a direct or indirect impact on the river flows in the dry zone. Synthetic climate change scenarios based on predicted climate variations were considered for future streamflow generation and results indicate that HEC-HMS in combination with SPI analysis is a useful tool in low flow analysis.","PeriodicalId":6855,"journal":{"name":"2021 Moratuwa Engineering Research Conference (MERCon)","volume":"53 1","pages":"504-509"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78676488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Manufactured Sand as River Sand Replacement for Masonry Binding Mortar 人造砂代替河砂用于砌体粘结砂浆
2021 Moratuwa Engineering Research Conference (MERCon) Pub Date : 2021-07-27 DOI: 10.1109/MERCon52712.2021.9525718
Kosalya Sundaralingam, Arvinthan Peiris, N. Sathiparan
{"title":"Manufactured Sand as River Sand Replacement for Masonry Binding Mortar","authors":"Kosalya Sundaralingam, Arvinthan Peiris, N. Sathiparan","doi":"10.1109/MERCon52712.2021.9525718","DOIUrl":"https://doi.org/10.1109/MERCon52712.2021.9525718","url":null,"abstract":"Binding mortar establish as an essential part of masonry for binding the masonry units together. Natural sand or river sand is used as a fine aggregate with cement for masonry binding mortar. Although the demand for river sand increases rapidly, on another side, the supply of good quality river sand is reduced due to restrictions in river sand mining. Therefore, there is increasing interest in finding alternative materials for river sand. Manufactured sand is one of the alternatives as it has some advantages over river sand. It provides a better contribution to the strength of the cementitious material, better workability, lesser cement consumption, and eco-friendly. The present study is focused on the progress of a sustainable masonry binding mortar by experimental investigations with manufactured sand as a replacement for river sand. Test for compressive strength was conducted on brick, binding mortar with various combinations of river sand and manufactured sand and masonry prism with different binding mortar. Test results showed that manufactured sand incorporated binding mortar not only shows better compressive strength itself but also significantly improved the compressive strength of masonry.","PeriodicalId":6855,"journal":{"name":"2021 Moratuwa Engineering Research Conference (MERCon)","volume":"41 1","pages":"403-408"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78985332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Enhancing the Thermal Performance of Epoxy Adhesive used in the CFRP/Concrete Bond 提高环氧胶粘剂在CFRP/混凝土粘结中的热工性能
2021 Moratuwa Engineering Research Conference (MERCon) Pub Date : 2021-07-27 DOI: 10.1109/MERCon52712.2021.9525677
C. Widanage, J. Gamage, V. Attanayake
{"title":"Enhancing the Thermal Performance of Epoxy Adhesive used in the CFRP/Concrete Bond","authors":"C. Widanage, J. Gamage, V. Attanayake","doi":"10.1109/MERCon52712.2021.9525677","DOIUrl":"https://doi.org/10.1109/MERCon52712.2021.9525677","url":null,"abstract":"Epoxy adhesive used as the bonding agent in the Carbon Fibre Reinforced Polymer/concrete bond shows poor thermal performance. Therefore, this experimental study focused on modifying the epoxy adhesive by blending recycled Polyethylene terephthalate (PET) fibres to enhance thermal performance. The single-lap shear test was conducted by varying the fibre content in the epoxy adhesive to determine the optimum PET fibre to develop the modified epoxy adhesive. The optimum PET fibre content was selected as 30% of the volume of epoxy. The modified adhesive showed a successful bond strength enhancement in both ambient and elevated temperature conditions when compared to the pure epoxy adhesive. The mechanical properties were tested for the developed epoxy-based adhesive. The modified epoxy adhesive achieved an average bond strength of 827.31 MPa (at 30 °C) for 150 mm bond length. Although the glass transition temperature of pure epoxy was between 60 °C and 80 °C, it was between 120°C and 150 °C for the modified epoxy adhesive.","PeriodicalId":6855,"journal":{"name":"2021 Moratuwa Engineering Research Conference (MERCon)","volume":"16 1","pages":"281-285"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87477998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Comparison of Time Series Forecast Models for Rainfall and Drought Prediction 降雨与干旱时间序列预报模型的比较
2021 Moratuwa Engineering Research Conference (MERCon) Pub Date : 2021-07-27 DOI: 10.1109/MERCon52712.2021.9525690
Narmada Ponnamperuma, Lalith Rajapakse
{"title":"Comparison of Time Series Forecast Models for Rainfall and Drought Prediction","authors":"Narmada Ponnamperuma, Lalith Rajapakse","doi":"10.1109/MERCon52712.2021.9525690","DOIUrl":"https://doi.org/10.1109/MERCon52712.2021.9525690","url":null,"abstract":"Forecasting of rainfall is important to be prepared for future weather-related disasters. Rainfall data can be categorized as time series data because rainfall data can be recorded in chronological order. Time series forecast is used in fields like economics, environmental, and engineering predictions as a decision support factor. Due to the importance, many models and methodologies have been developed for time series forecasts according to the types of inputs, expected outcomes, and easy applicability. This research was conducted to identify the most appropriate time series forecast model for rainfall prediction. A regression type model and a neural network model were selected to identify which type of forecast model is more suitable for rainfall prediction. ARIMA model and Recurrent Neural Network model of Non-linear Auto-Regressive Moving Average were selected as the candidate prediction models for time series forecast and the models were developed for rainfall forecast. From the developed models, it was observed that the RNN models are suitable for long-term prediction of rainfall and drought with the availability of a higher number of past rainfall data while the ARIMA model is more suitable for prediction of rainfall where there is less past recorded rainfall data for a short-term forecast period.","PeriodicalId":6855,"journal":{"name":"2021 Moratuwa Engineering Research Conference (MERCon)","volume":"64 1","pages":"626-631"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86835733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 4
Invited Talk: Flexible electronics fabricated by electric field- enhanced electrospinning 特邀演讲:电场增强静电纺丝制造柔性电子器件
2021 Moratuwa Engineering Research Conference (MERCon) Pub Date : 2021-07-27 DOI: 10.1109/mercon52712.2021.9525700
V. Dau
{"title":"Invited Talk: Flexible electronics fabricated by electric field- enhanced electrospinning","authors":"V. Dau","doi":"10.1109/mercon52712.2021.9525700","DOIUrl":"https://doi.org/10.1109/mercon52712.2021.9525700","url":null,"abstract":"","PeriodicalId":6855,"journal":{"name":"2021 Moratuwa Engineering Research Conference (MERCon)","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87159908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Effect of Halide Ion in the Perovskite on Perovskite Solar Cell Performances 钙钛矿中卤化物离子对钙钛矿太阳能电池性能的影响
2021 Moratuwa Engineering Research Conference (MERCon) Pub Date : 2021-07-27 DOI: 10.1109/MERCon52712.2021.9525717
Sarith Sankalpa Ranasinghe, Yehan Laknath Kuruppu, G. Sewvandi
{"title":"Effect of Halide Ion in the Perovskite on Perovskite Solar Cell Performances","authors":"Sarith Sankalpa Ranasinghe, Yehan Laknath Kuruppu, G. Sewvandi","doi":"10.1109/MERCon52712.2021.9525717","DOIUrl":"https://doi.org/10.1109/MERCon52712.2021.9525717","url":null,"abstract":"In this paper, a p-i-n perovskite solar cell was studied using Solar Cell Capacitance Simulator (SCAPS). A perovskite solar cell with MAPbI<inf>3</inf> and a perovskite solar cell with MAPbBr<inf>3</inf> as the light-absorbing materials have been simulated and compared the effect of the halide ion on solar cell performances. The efficiency of MAPbI<inf>3</inf> and MAPbBr<inf>3</inf> were reached 16.8% and 5.14% respectively. Also, the thickness of each MAPbI<inf>3</inf> and MAPbBr<inf>3</inf> was varied from <tex>$0.1 mumathrm{m}$</tex> to <tex>$1.2 mumathrm{m}$</tex> and the best results were observed at <tex>$0.5 mumathrm{m}$</tex> and <tex>$0.4 mumathrm{m}$</tex> thickness of MAPbI<inf>3</inf> and MAPbBr<inf>3</inf> films, respectively. A considerable effect of halide ions on perovskite solar cell performances can be attributed to the variation of light absorption with the halide ions.","PeriodicalId":6855,"journal":{"name":"2021 Moratuwa Engineering Research Conference (MERCon)","volume":"14 1","pages":"169-172"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88200233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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