Introduction

Today, with many IoT devices and the development of Internet technologies, both wired and wireless connectivity play a crucial role in offering a wide range of services to end-users. Moreover, such communication and networking technologies have influenced individuals, institutions, governments, and industries. As a result, communication technologies have become an indispensable part of daily life. Recently, Machine Learning (ML) technologies have achieved breakthrough advances. When combined with communication technologies, the achievement in AI has created unique applications such as smart cities, self-driving cars, etc.

Our research group focuses on the study and development of high-speed, dependable, and flexible networking technologies, using theoretical and practical techniques to incorporate social, information, device, and energy factors. We study to leverage AI in enhancing and optimizing network performance. We’re also looking into solutions for analyzing and mining data collected by IoT devices. See the slides here for more detail.

Contact: Dr. Nguyen Phi Le, Email: lenp@soict.hust.edu.vn

Group website: http://icn.bkai.ai/

Research Directions

  • Network optimization: Exploiting machine learning, deep learning, reinforcement learning, meta-heurisctic techniques to optimize network performance.
  • Data mining in IoT networks: Focusing on processing, analyzing and mining data collected from IoT devices.
  • AI in networking: Applying various machine learning and deep learning techniques including graph networks, deep reinforcement learning, etc., to analyze and predict the network behavior. Leveraging AI in controlling network operations.
  • Distributed systems: Addressing different problems in distributed systems such as Synchronization, Replication and Consistency, Fault tolerance, etc.
  • New generation network: Solving problems of NGN in expanding the existing access network infrastructure into networks capable of satisfying the user’s requirements.
  • QoS-QoE: Proposing adaptive mechanisms to predict and optimize QoS/QoE in network systems.
  • Internet of Things: Addressing different issues of IoT systems such as security problems, lack of regulation, limited bandwidth, etc.

Research problems

  • Optimization problems in Wireless Rechargeable Sensor Networks: We focus on a new wireless charging paradigm that considers a variety of factors such as charging path, charging time, target coverage, and connectivity. Furthermore, our system considers various optimization goals, including minimizing the number of mobile chargers, optimizing the depot placement, and extending the network lifetime. To solve the problem, we go from theoretical modeling to applying state-of-the-art technologies. Specifically, we leverage reinforcement learning and deep reinforcement learning, fuzzy logic, genetic algorithms to propose novel charging algorithms for wireless rechargeable IoT networks.
  • Mobile air quality monitoring network: This research topic, part of the VinIF-funded Fi-Mi project (http://fi-mi.vn), presents a new mobile air quality monitoring network based on vehicle-mounted sensors. We explore various research issues, such as resource allocation, effective communication, data analysis, and data mining. The resource allocation problem is solved using optimization techniques such as reinforcement learning, fuzzy logic, and meta-heuristics. A mathematical model for opportunistic communication in mobile air quality monitoring networks is also proposed. We then leverage deep reinforcement learning for offloading data from devices to the servers. Finally, we use machine learning methodologies to calibrate the acquired data and propose deep learning models for spatiotemporal prediction problems.
  • Satellite precipitation calibration: We investigate a fascinating research problem that is how to calibrate the satellite precipitation data. Our method uses deep learning techniques to blend satellite data that is fine-grained but inaccurate with the coarse-but-accurate data from ground-based monitoring stations. We then leverage graph neural networks to model the spatial correlation between the ground-based monitoring stations. Besides, recurrent neural networks are utilized to capture the data’s temporal properties.
  • Prediction of water levels on rivers in Vietnam: This study focuses on data mining regarding river discharge and water levels in Vietnam. For hydrological research and flood prediction, forecasting river discharge and water levels have long been necessary. However, existing machine learning-based methods cope with severe flaws such as a lack of training data, noise in the obtained data, and the difficulty of altering the model’s hyper-parameters. In this research, we address at the same time these three challenges. Specifically, we apply data preprocessing techniques such as SSA to clean the data before feeding it into the forecasting models. Furthermore, we propose novel deep learning models that employ ensemble learning techniques and graph neural networks to capture both temporal and spatial correlation and extract relevant information from historical data. Furthermore, optimization techniques like metaheuristics are used to obtain the optimal hyper-parameters automatically.
  • Traffic prediction and intelligent routing: In this research, we study how to learn and predict networks’ future behavior dynamically. From that, we design algorithms to control the network operations efficiently and intelligently. Several research problems are taking into account, such as exploiting the Graph Neural Networks to capture the spatial relation of the network and then leveraging deep learning to predict the network traffic; using reinforcement learning to guide the packets; utilizing metaheuristic algorithms and linear programming to optimize the routing paths. We perform experiments on network simulators such as OMNET, NS2, and real datasets such as Brain, Abilene, and Geant.
  • Applying ML to Software-Defined Network =>  Knowledge-defined Network: Applying AI to the management of computer networks, making it to be a self-adaptive one. This means every network node will be an AI node, which is able to make decisions automatically. However, these network nodes have only a local view and a local control, hence, applying Artificial Intelligence to each network node is not trivial. For this purpose, a centralized control architecture, e.g. Software-defined Network (SDN), is a promising candidate. In this work, we decide to develop a knowledge layer on top of the SDN architecture, forming a Knowledge-defined Network.
  • Replication and consistency in heterogeneous and Distributed SDN networks: Proposing an East-West interface, called SINA, to provide the interoperability of a heterogeneous and distributed SDN network. In addition, a novel Reinforcement Learning-based consistency algorithm is introduced for an adaptive Quorum-based replication mechanism.
  • Applying Federated Learning to SDN: The learning phase of a multi-domain SDN network must address the following problems: both solutions of 1) learning separately in each domain and 2) collecting all data from different controllers and launching the training phase in a centralized server are not efficient due to the computational cost, training time, and the accuracy. That motivates us to apply Federated Learning, in which distributed SDN controllers cooperatively train a centralized learning model while do not share the training data for preserving data privacy.

Team Members

Dr. Nguyen Phi Le
Team Leader

Dr. Tran Hai Anh
Member

Assoc. Prof. Do Phan Thuan
Member

Dr. Nguyen Thanh Hung
Member

Assoc. Prof. Tran Quang Duc
Member

Latest Publications

Publications in 2023

  1. Huynh Thanh Trung, Nguyen Minh Hieu, Nguyen Thanh Tam, Phi Le Nguyen, Weidlich Matthias, Nguyen Quoc Viet Hung, Aberer Karl. Efficient Integration of Multi-Order Dynamics and Internal Dynamics in Stock Movement Prediction. The 16th ACM International WSDM Conference 2023. 27/02/2023
  2. Thanh Trung Nguyen, Minh Hai Vu, Phi Le Nguyen, Phan Thuan Do, Kien Nguyen. A Q-learning-based Multipath Scheduler for Data Transmission Optimization in Heterogeneous Wireless Networks. CCNC 2022. 08/01/2023

Publications in 2022

  1. Anh Duy Nguyen, Phi Le Nguyen, Viet Hung Vu, Quoc Viet Pham, Viet Huy Nguyen, Minh Hieu Nguyen, Thanh Hung Nguyen, Kien Nguyen. Accurate Discharge and Water Level Forecasting Using Ensemble Learning with Genetic Algorithm and Singular Spectrum Analysis-based Denoising. Nature Scientific Reports. 01/11/2022
  2. Papa Bara, Tran-Tuan Chu, Mohamed Aymen Labiod, Brice Augustin, Hai-Anh Tran, Abdelhamid Mellouk. Experimental Evaluation of Multiple Multipath Schedulers over Various Urban Mobile Environments. The Symposium on Information and Communication Technology (SoICT). Hạ Long, Vietnam. 01/12/2022
  3. Hiroaki Motohashi, Phi Le Nguyen, Kien Nguyen, Hiroo Sekiya. Implementation of P4-based Schedulers for Multipath Communication. IEEE Access. 20/07/2022
  4. Nam-Thang Hoang, Cong-Son Duong, Cong-Son Duong, Van Tong, Hai-Anh Tran. Knowledge-defned Heterogeneous Network: Use-case of QoS-based Server and Route Selection in Large-scale. SoICT 2022: The 11th International Symposium on Information and Communication Technology. 150-157. Hanoi, Vietnam. 01/12/2022
  5. Trung Thanh Nguyen, Hoang Dang Nguyen, Thanh Hung Nguyen, Huy Hieu Pham, Ichiro Ide, Phi Le Nguyen. A Novel Approach for Pill-Prescription Matching with GNN Assistance and Contrastive Learning. The 19th Pacific Rim International Conference on Artificial Intelligence (PRICAI 2022). 01/12/2022
  6. Đào Vũ Hiệp, Mạc Đình Hiếu, Trần Quang Đức. Noise-aware deep learning algorithm for one-stage multispectral pedestrian detection. Journal of Electronic Imaging. 24/05/2022
  7. Tran-Tuan Chu, Mohamed-Aymen Labiod, Hai-Anh Tran, Abdelhamid MELLOUK. GADaM: Generic Adaptive Deep-learning-based Multipath Scheduler Selector. IEEE International Conference on Communications (ICC) 2022. 16/05/2022
  8. Trong-Tung Nguyen, Hieu H. Pham, Phi Le Nguyen, Thanh Hung Nguyen, and Minh Do. Multi-stream Fusion for Class Incremental Learning in Pill Image Classification. The 16th Asian Conference on Computer Vision (ACCV2022). 04/12/2022
  9. Anh Duy Nguyen, Thuy Dung Nguyen, Huy Hieu Pham, Thanh Hung Nguyen, Phi Le Nguyen. Image-based Contextual Pill Recognition with Medical Knowledge Graph Assistance. 14th Asian Conference on Intelligent Information and Database Systems (ACIIDS), 2022. 28/11/2022
  10. Kien Nguyen, Phi Le Nguyen, Hiroo Sekiya. A Host-based Investigation of IPv6 in Academia: The Cases of Japan and Vietnam. Kien Nguyen, Phi Le Nguyen, Hiroo Sekiya. 08/01/2022
  11. Thanh Toan Nguyen, Thanh Tam Nguyen, Thanh Trung Huynh, Viet Hung Vu, Phi Le Nguyen, Jun Jo, Quoc Viet Hung Nguyen. Poisoning GNN-based Recommender Systems with Generative Surrogate-based Attacks. Transactions on Information Systems. 19/10/2022
  12. Ngoc Bui, Phi Le Nguyen, Viet Anh Nguyen, Phan Thuan Do. A Deep Reinforcement Learning-based Adaptive Charging Policy for WRSNs. The 19th IEEE International Conference on Mobile Ad-Hoc and Smart Systems (MASS 2022). 20/10/2022
  13. Hieu Dinh, Nang Hung Nguyen, Trung Thanh Nguyen,Thanh Hung Nguyen, Truong Thao Nguyen, Phi Le Nguyen. Deep Reinforcement Learning-based Offloading for Latency Minimization in 3-tier V2X Networks. 2022 IEEE Wireless Communications and Networking Conference (WCNC). 1-6. 10/04/2022
  14. La Van Quan, Minh Hieu Nguyen, Thanh Hung Nguyen, Kien Nguyen, Phi Le Nguyen. On the Global Maximization of Network Lifetime in Wireless Rechargeable Sensor Networks. ACM Transaction on Sensor Networks. 01/01/2022
  15. Trần Hoàng Hải, Nguyễn Thanh Hùng, Nguyễn Nhất Hải, Đặng Tuấn Linh, Huỳnh Quyết Thắng. eHUST - Một mô hình mẫu cho hệ thống quản trị Nhà trường hỗ trợ Chuyển đổi số tại Việt Nam. Thúc đấy Chuyển đổi số, Kinh tế tuần hoàn và kinh tế xanh - Hướng tới mục tiêu phát triển bền vững. 18-26. Trường Đại học Phenikaa. 12/11/2022
  16. Viet Dung Nguyen, Phi Le Nguyen, Kien Nguyen, Phan Thuan Do. Constant Approximation for Opportunistic Sensing in Mobile Air Quality Monitoring System. Computer Networks Journal. 15/01/2022
  17. Minh Hai Vu, Giang T. T. Nguyen, Hai Dang Tran, Thanh Trung Nguyen, Phan Thuan Do, Phi Le Nguyen, Kien Nguyen. An Empirical Study of MPQUIC Schedulers in Mobile Wireless Networks. SoICT2022. 193–200. 01/12/2022
  18. Hai-Anh Tran, Duc Tran, and Abdelhamid Mellouk. State-Dependent Multi-Constraint Topology Configuration for Software-Defined Service Overlay Networks. IEEE/ACM Transactions on Networking. 01/03/2022
  19. Manh-Tien-Anh Nguyen, Sondes Bannour Souihi, Hai-Anh Tran, and Sami Souihi. When NLP meets SDN: an application to Global Internet eXchange Network. IEEE International Conference on Communications (ICC), 2022. 16/05/2022
  20. Hung Cuong Nguyen, Manh Cuong Dao, Thanh Trung Nguyen, Ngoc Khanh Doan, Thanh Hung Nguyen, Truong Thao Nguyen, Phi Le Nguyen. Deep Reinforcement Learning-based Charging Algorithm for Target Coverage and Connectivity in WRSNs. he 2022 Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (IEEE PIMRC), 2022. 12/10/2022
  21. Tuan Anh Nguyen Dinh, Anh Duy Nguyen, Truong Thao Nguyen, Thanh Hung Nguyen, Phi Le Nguyen. Spatial-temporal Coverage Maximization in Vehicle-based Mobile Crowdsensing for Air Quality Monitoring. 2022 IEEE Wireless Communications and Networking Conference (WCNC). 1-6. 10/04/2022
  22. Duc-Huy Pham, Quang-Anh Do, Thanh Thi-Hien Duong, Thi Lan Le, Phi-Le Nguyen. End-to-end Visual-guided Audio Source Separation with Enhanced Losses. 2022 Asia Pacific Signal and Information Processing Association Annual Summit and Conference (APSIPA ASC). Thai Lan. 07/11/2022
  23. Nam-Thang Hoang, Hai-Nam Nguyen, Hai-Anh Tran, and Sami Souihi. A Novel Adaptive East–West Interface for a Heterogeneous and Distributed SDN Network. Electronics. 16/03/2022
  24. Minh Hieu Nguyen, Viet Huy Nguyen, Thanh Trung Huynh, Thanh Hung Nguyen, Quoc Viet Hung Nguyen, Phi Le Nguyen. A Lightweight and Efficient GA-based Model-Agnostic Feature Selection Scheme for Time Series Forecasting. 14th Asian Conference on Intelligent Information and Database Systems (ACIIDS), 2022. 09/12/2022
  25. Trung Thanh Nguyen, Truong Thao Nguyen, Thanh Hung Nguyen, Phi Le Nguyen. Fuzzy Q-learning-based Opportunistic Communication for MEC-enhanced Vehicular Crowdsensing. IEEE Transactions on Network and Service Management. 26/07/2022
  26. Nang Hung Nguyen, Phi Le Nguyen, Duc Long Nguyen, Trung Thanh Nguyen, Thuy Dung Nguyen, Huy Hieu Pham, Thanh Hung Nguyen, Truong Thao Nguyen. FedDRL: Deep Reinforcement Learning-based Adaptive Aggregation for Non-IID Data in Federated Learning. 51st International Conference on Parallel Processing (ICPP). 29/08/2022
  27. Thu Hang Phung, Duc Long Nguyen, Viet Hung Vu, Thanh Trung Huynh, Thanh Hung Nguyen, Phi Le Nguyen. Unsupervised Air Quality Interpolation with Attentive Graph Neural Network. SoICT2022. 1-6. HaLong. 01/12/2022

Publications in 2021

  1. Trung Thanh Nguyen, Truong Thao Nguyen, Tuan Anh Nguyen Dinh, Thanh-Hung Nguyen, Phi Le Nguyen. Q-learning-based Opportunistic Communication for Real-time Mobile Air Quality Monitoring Systems. 2021 IEEE International Performance, Computing, and Communications Conference (IPCCC). 1-6. 29/10/2021
  2. Phi Le Nguyen, Yusheng Ji, Minh Khiem Pham, Hieu Le, Thanh Hung Nguyen. (1+epsilon)2- and Polynomial-Time Approximation Algorithms for Network Lifetime Maximization with Relay Hop Bounded Connected Target Coverage in WSNs. IEEE Sensors. 9577 - 9599. 13/01/2021
  3. Van An Le, Tien Thanh Le, Phi Le Nguyen, Huynh Thi Thanh Binh, Yusheng Ji. Multi-time-step Segment Routing based Traffic Engineering Leveraging Traffic Prediction. IFIP/IEEE International Symposium on Integrated Network Management. 1-8. France. 17/05/2021
  4. Van TONG, Sami SOUIHI, Hai Anh TRAN and Abdelhamid MELLOUK. Machine Learning based Root Cause Analysis for SDN Network. IEEE GLOBECOM 2021. 07/12/2021
  5. Thanh Thi-Hien Duong, Manh Nguyen Huu, Hai Nghiem Thi, Thi-Lan Le, Phi-Le Nguyen, Quoc-Cuong Nguyen. Visual-guided audio source separation: an empirical study. 2021 International Conference on Multimedia Analysis and Pattern Recognition (MAPR). Hanoi. 15/10/2021
  6. Thanh Le-Cong, Xuan Bach Le D., Phi Le Nguyen, Quyet Thang Huynh. Usability and Aesthetics: Better Together for Automated Repair of Web Pages. 2021 IEEE 32nd International Symposium on Software Reliability Engineering (ISSRE). 1-6. 25/10/2021
  7. Nang Hung Nguyen, Phi Le Nguyen, Hieu Dinh, Thanh Hung Nguyen, Kien Nguyen. Multi-Agent Multi-Armed Bandit Learning for Offloading Delay Minimization in V2X Networks. 2021 IEEE 19th International Conference on Embedded and Ubiquitous Computing (EUC). 20/10/2021
  8. Hai-Anh TRAN, Thi-Thanh-Tu NGUYEN, Sami SOUIHI, and Abdelhamid MELLOUK. Towards a Novel Congestion Notification Algorithm for a Software-Defined Data Center Networks. IFIP/IEEE International Symposium on Integrated Network Management, 2021. 99-106. Bordeaux, France. 17/05/2021
  9. Tran Bao Hieu, Nguyen Duc Anh, Hoang Duc Viet, Nguyen Manh Hiep, Pham Ngoc Bao Anh, Hoang Gia Bao, Bui Hai Phong, Thanh Hung Nguyen, Nguyen Phi Le, Le Thi Lan. MC-OCR Challenge 2021: A Multi-modal Approach for Mobile-Captured Vietnamese Receipts Recognition. 2021 RIVF International Conference on Computing and Communication Technologies (RIVF). Hanoi, Vietnam. 19/08/2021
  10. Vu Hiep Dao, Hieu Mac, Duc Tran. A Real-time Multispectral Algorithm for Robust Pedestrian Detection. 2021 RIVF International Conference on Computing and Communication Technologies (RIVF). Hanoi, Vietnam. 19/08/2021
  11. Thuy Dung Nguyen, Tuyen Nguyen, Thanh Hung Nguyen, Kien Nguyen, Phi Le Nguyen. Joint Optimization of Charging Location and Time for Network Lifetime Extension in WRSNs. IEEE Transactions on Green Communications and Networking. 11/11/2021
  12. Kien Nguyen, Phi Le Nguyen, Li Zhe-tao, Hiroo Sekiya. Empowering 5G Mobile Devices with Network Softwarization. IEEE Transactions on Network and Service Management. 30/06/2021
  13. Viet An Nguyen, Viet Hung, Van Sang Doan, Thanh Hung Nguyen, Phan Thuan Do, Kien Nguyen, Phi Le Nguyen, Minh Thuy Le. Realizing Mobile Air Quality Monitoring System: Architectural Concept and Device Prototype. 2021 26th IEEE Asia-Pacific Conference on Communications (APCC). 11/10/2021
  14. Minh Hieu Nguyen, Phi Le Nguyen, Kien Nguyen, Van An Le, Thanh-Hung Nguyen, Yusheng Ji. PM2.5 Prediction Using Genetic Algorithm-based Feature Selection and Encoder-Decoder Model. IEEE Access. 57338 - 57350. 05/04/2021
  15. Do Bao Son, Vu Tri An, Trinh Thu Hai, Binh Minh Nguyen, Phi Le Nguyen, Huynh Thi Thanh Binh. Fuzzy Deep Q-learning Task Offloading in Delay Constrained Vehicular Fog Computing. 2021 International Joint Conference on Neural Networks (IJCNN). 18/07/2021
  16. Viet Dung Nguyen ; Ba Thai Pham ; Phan Thuan Do. Efficient algorithms for maximum induced matching problem in permutation and trapezoid graphs. Fundamenta Informaticae. 257-283. 22/07/2021
  17. Thanh T. H. Duong, Phi Le Nguyen, Hong-Son Nguyen, Duc-Chien Nguyen, Huy Phan, Ngoc Q. K. Duong. Speaker count: a new building block for speaker diarization. 2021 15th Asia-Pacific Signal and Information Processing Association Annual Summit and Conference (APSIPA ASC). 1-6. Japan. 14/12/2021
  18. The-Anh Le, Quyet-Thang Huynh, Thanh-Hung Nguyen. A New Method to Improve Quality Predicting of Software Project Completion Level. Industrial Networks and Intelligent Systems, INISCOM 2021. 211-219. Hanoi. 22/04/2021
  19. Duc-Huy LE, Hai-Anh TRAN, and Sami SOUIHI. A Reinforcement Learning-based solution for Intra-domain Egress Selection. IEEE International Conference on High Performance Switching and Routing (HPSR21). 01-06. Paris, France. 07/06/2021
  20. Tran Thi Huong, Le Van Cuong, Ngo Minh Hai, Nguyen Phi Le, Le Trong Vinh, Huynh Thi Thanh Binh. A bi-level optimized charging algorithm for energy depletion avoidance in wireless rechargeable sensor networks. Applied Intelligence. 1-23. 16/08/2021
  21. Phan Thuan Do, Thi Thu Huong Tran, Vincent Vajnovszki. The equidistribution of some Mahonian statistics over permutations avoiding a pattern of length three. Discrete Mathematics. 112684. 09/10/2021
  22. Phi Le Nguyen, Nang Hung Nguyen, Tuan Anh Nguyen Dinh, Khanh Le, Thanh Hung Nguyen, Kien Nguyen. QIH: an Efficient Q-learning Inspired Hole-Bypassing Routing Protocol for WSNs. IEEE Access. 20/08/2021
  23. Anh Duy Nguyen, Viet Hung Vu, Minh Hieu Nguyen, Duc Viet Hoang, Thanh Hung Nguyen, Kien Nguyen, and Phi Le Nguyen. Efficient Prediction of Discharge and WaterLevels Using Ensemble Learning andSingular-Spectrum Analysis-based Denoising. The 34th International Conference on Industrial, Engineering & Other Applications of Applied Intelligent Systems IEA/AIE 2021. 24/07/2021
  24. Van An Le, Tien Thanh Le, Phi Le Nguyen, Huynh Thi Thanh Binh, Rajendra Akerkarx, Yusheng Ji. GCRINT: Network Traffic Imputation Using Graph Convolutional Recurrent Neural Network. IEEE International Conference on Communications. 1-8. Canada. 14/06/2021
  25. Phi Le Nguyen, Van Quan La, Anh Duy Nguyen, Thanh Hung Nguyen, Kien Nguyen. An On-demand Charging for Connected Target Coverage in WRSNs using Fuzzy Logic and Q-learning. MDPI Sensors. 12/08/2021
  26. Duc-Huy LE, Hai-Anh TRAN, Sami SOUIHI, and Abdelhamid MELLOUK. An AI-based Traffic Matrix Prediction Solution for Software-Defined Network. IEEE International Conference on Communications (ICC), 2021. 01-06. Online. 14/06/2021
  27. Khanh-Van Nguyen, Chi-Hieu Nguyen, Phi Le Nguyen, Tien Van Do, Imrich Chlamtac. Energy-efficient routing in the proximity of a complicated hole in wireless sensor networks. Wireless Networks -Springer. 01/01/2021
  28. Van TONG, Sami SOUIHI, Hai Anh TRAN and Abdelhamid MELLOUK. SDN-Based Application-Aware Segment Routing for Large-Scale Network. IEEE Systems Journal. 06/11/2021
  29. Hai Nam Nguyen, Hai Anh Tran, Scott Fowler, Sami Souihi. A survey of Blockchain technologies applied to software-defined networking: Research challenges and solutions. IET Wireless Sensor Systems. 21/10/2021
  30. Anh Son TA. Sovling problem. NICS. 17/01/2021
  31. Manh Hung Dinh, Ngoc Thach Hoang, Mai Phuong Nguyen, Phi Le Nguyen, Phan Thuan Do. Node Deployment Optimization for Target Coverage and Connectivity in WSNs with a Delay-constrained Mobile Sink. ICCE 2020. Phu Quoc Island. 13/01/2021