2022年8月16日，中国科学院南海海洋研究所热带海洋环境国家重点实验室LTO、广东省海洋遥感重点实验室LORS的斯里兰卡留学生硕士研究生Pathira Arachchilage Kalani Randima Lakshani（以下简称Randima）进行了硕士学位论文答辩，答辩题目为“Research on marine plastics detection based on multi-source remote sensing data（基于多源遥感数据的海洋塑料探测研究）”。
     Randima同学的导师为中国科学院南海海洋研究所研究员、南方海洋科学与工程广东省实验室(广州)引进高端领军人才唐丹玲教授。
     答辩专家委员会由华东师范大学李道季教授（答辩委员会主席）、中国海洋大学管磊教授、中国科学院南海海洋研究所唐世林研究员和王素芬副研究员组成，刘宇鹏助研担任答辩秘书。
     Randima的论文利用哨兵系列卫星遥感数据，结合国际共享的大型漂浮塑料实测数据集，利用混合像元分解、光谱角填图和直方图分析等方法，反演了珠江口、海地、希腊、加纳附近海域的海洋大型漂浮塑料；提出了基于图像灰度值的高通滤波和各波段遥感反射比的散点图的海洋大型漂浮塑料识别阈值分割法（以0.05为阈值）。研究成果有助于推动高分辨的海洋漂浮塑料遥感监测，可为海洋塑料垃圾的动态变化认识和监测手段提供借鉴和参考。
     答辩在答辩委员会主席李道季教授的主持下有序展开，答辩委员4位专家依次对Randima的答辩提出了宝贵的建议和中肯的评价。最后，经无记名投票，答辩委员会一致同意通过学位论文答辩，建议授予硕士学位。
     随后，中国科学院南海海洋研究所副研究员及中国科学院中国-斯里兰卡联合科教中心主管潘刚向斯里兰卡留学生Randima顺利通过学位论文答辩表示热烈祝贺，对Randima送出寄语，并抛出橄榄枝，欢迎Randima随时再来中国留学或者访问。
     感谢各位答辩委员会专家的指导，恭贺Randima同学硕士学位论文答辩顺利完成，并祝愿Randima在未来的学习和工作中乘风破浪、前程似锦！

Postgraduate training | Pathira Arachchilage Kalani Randima Lakshani, a Sri Lankan student of the South China Sea Institute of Oceanography, Chinese Academy of Sciences, passed her master's thesis defense

     On August 16, 2022, Pathira Arachchilage Kalani Randima Lakshani (short for Randima), a Sri Lankan graduate student of the State Key Laboratory of Tropical Oceanology (LTO), South China Sea Institute of Oceanography, Chinese Academy of Sciences, and Guangdong Provincial Key Laboratory of Ocean Remote Sensing (LORS), South China Sea Institute of Oceanography, Chinese Academy of Sciences, conducted a master's thesis. The defense is titled "Research on marine plastics detection based on multi-source remote sensing data".
     Randima is the student of Dr. Tang Danling, a professor at the South China Sea Institute of Oceanography, Chinese Academy of Sciences, and a high-end leading talent introduced by the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou).
     The defense expert committee is composed of Professor Li Daoji of East China Normal University (chair of the defense committee), Professor Guan Lei of Ocean University of China, Professor Tang Shilin and associate Professor Wang Sufen of the South China Sea Institute of Oceanography, Chinese Academy of Sciences, and assistant researcher Liu Yupeng serves as the defense secretary.
     Based on the Sentinel series satellite remote sensing data, and the international shared large-scale floating plastic measured dataset, large marine floating plastics in the ocean around the Pearl River Estuary, Haiti, Greece, and Ghana were inverted using spectral angle mapping, mixed pixel decomposition and histogram analysis in Randima’s thesis. Meanwhile, a threshold segmentation method (with 0.05 as the threshold) for the identification of large marine floating plastics based on image gray value high-pass filtering and scattergrams of remote sensing reflectance in each band is proposed. The research results will help promote high-resolution remote sensing monitoring of marine floating plastics, and provide references for the understanding and monitoring methods of dynamic changes in marine plastic waste.
     The defense was carried out in an orderly manner under the auspices of Professor Li Daoji, chairman of the defense committee. The four experts of the defense committee put forward valuable suggestions and pertinent comments on Randima's defense in turn. Finally, after a secret ballot, the defense committee unanimously agreed to pass the dissertation defense and recommend conferring a master's degree to Randima.
     Later, Pan Gang, associate Professor of the South China Sea Institute of Oceanography, Chinese Academy of Sciences, and the officer of the China-Sri Lanka Joint Center for Education and Research, Chinese Academy of Sciences, extended warm congratulations to Randima for successfully passing the dissertation defense, and welcomed Randima to come to China for study or visit anytime.
     We express our sincere thanks to all the experts of the defense committee for their guidance, congratulate Randima for successfully completing the defense of her master's thesis, and wish Randima a bright future in her future study and work!