Associate Professor Chaiyachet Saivichit, Ph.D.
รศ. ดร.ชัยเชษฐ์ สายวิจิตร
Education
- PhD (Communication Networking) Imperial College London, U.K.
- BEng(Hons), Communications and Electronics Engineering, University of Bristol, U.K.
Email: Chaiyachet.S@chula.ac.th
Research Interest
- Communication Networking
- Intelligent techniques in Communication Networking
- Network Design, Operation and Management Optimisation
- Graph Theoretical Issues in Communications
- Telecommunication Economics
- Network Reliability, Survivability and Trustworthiness
- M.A.D. Networking
(Motoring, Manufacturing, Medical; Agriculture, Aging, Aviation; Disaster, Disability, Defense)
Research Cluster
Link to
1.
Mon, E E; Ochiai, H; Saivichit, C; Aswakul, C
Bottleneck based gridlock prediction in an urban road network using long short-term memory Journal Article
In: Electronics (Switzerland), vol. 9, no. 9, pp. 1-20, 2020, ISSN: 20799292, (cited By 0).
@article{Mon2020,
title = {Bottleneck based gridlock prediction in an urban road network using long short-term memory},
author = {E E Mon and H Ochiai and C Saivichit and C Aswakul},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85093901328&doi=10.3390%2felectronics9091412&partnerID=40&md5=68c515291b67e71b13c2d718fa823ab7},
doi = {10.3390/electronics9091412},
issn = {20799292},
year = {2020},
date = {2020-01-01},
journal = {Electronics (Switzerland)},
volume = {9},
number = {9},
pages = {1-20},
publisher = {MDPI AG},
abstract = {The traffic bottlenecks in urban road networks are more challenging to investigate and discover than in freeways or simple arterial networks. A bottleneck indicates the congestion evolution and queue formation, which consequently disturb travel delay and degrade the urban traffic environment and safety. For urban road networks, sensors are needed to cover a wide range of areas, especially for bottleneck and gridlock analysis, requiring high installation and maintenance costs. The emerging widespread availability of GPS vehicles significantly helps to overcome the geographic coverage and spacing limitations of traditional fixed-location detector data. Therefore, this study investigated GPS vehicles that have passed through the links in the simulated gridlock-looped intersection area. The sample size estimation is fundamental to any traffic engineering analysis. Therefore, this study tried a different number of sample sizes to analyze the severe congestion state of gridlock. Traffic condition prediction is one of the primary components of intelligent transportation systems. In this study, the Long Short-Term Memory (LSTM) neural network was applied to predict gridlock based on bottleneck states of intersections in the simulated urban road network. This study chose to work on the Chula-Sathorn SUMO Simulator (Chula-SSS) dataset. It was calibrated with the past actual traffic data collection by using the Simulation of Urban MObility (SUMO) software. The experiments show that LSTM provides satisfactory results for gridlock prediction with temporal dependencies. The reported prediction error is based on long-range time dependencies on the respective sample sizes using the calibrated Chula-SSS dataset. On the other hand, the low sampling rate of GPS trajectories gives high RMSE and MAE error, but with reduced computation time. Analyzing the percentage of simulated GPS data with different random seed numbers suggests the possibility of gridlock identification and reports satisfying prediction errors. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.},
note = {cited By 0},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The traffic bottlenecks in urban road networks are more challenging to investigate and discover than in freeways or simple arterial networks. A bottleneck indicates the congestion evolution and queue formation, which consequently disturb travel delay and degrade the urban traffic environment and safety. For urban road networks, sensors are needed to cover a wide range of areas, especially for bottleneck and gridlock analysis, requiring high installation and maintenance costs. The emerging widespread availability of GPS vehicles significantly helps to overcome the geographic coverage and spacing limitations of traditional fixed-location detector data. Therefore, this study investigated GPS vehicles that have passed through the links in the simulated gridlock-looped intersection area. The sample size estimation is fundamental to any traffic engineering analysis. Therefore, this study tried a different number of sample sizes to analyze the severe congestion state of gridlock. Traffic condition prediction is one of the primary components of intelligent transportation systems. In this study, the Long Short-Term Memory (LSTM) neural network was applied to predict gridlock based on bottleneck states of intersections in the simulated urban road network. This study chose to work on the Chula-Sathorn SUMO Simulator (Chula-SSS) dataset. It was calibrated with the past actual traffic data collection by using the Simulation of Urban MObility (SUMO) software. The experiments show that LSTM provides satisfactory results for gridlock prediction with temporal dependencies. The reported prediction error is based on long-range time dependencies on the respective sample sizes using the calibrated Chula-SSS dataset. On the other hand, the low sampling rate of GPS trajectories gives high RMSE and MAE error, but with reduced computation time. Analyzing the percentage of simulated GPS data with different random seed numbers suggests the possibility of gridlock identification and reports satisfying prediction errors. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.
2.
Thirasupa, R; Saivichit, C; Aswakul, C
Cloud Infrastructure Design Model for Green Smart City: Case Study of Electricity Generating Authority of Thailand Journal Article
In: Lecture Notes in Electrical Engineering, vol. 621, pp. 135-147, 2020, ISSN: 18761100, (cited By 0; Conference of 10th International Conference on Information Science and Applications, ICISA 2019 ; Conference Date: 16 December 2019 Through 18 December 2019; Conference Code:235259).
@article{Thirasupa2020,
title = {Cloud Infrastructure Design Model for Green Smart City: Case Study of Electricity Generating Authority of Thailand},
author = {R Thirasupa and C Saivichit and C Aswakul},
editor = {Kim H -Y Kim K.J.},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85077494795&doi=10.1007%2f978-981-15-1465-4_15&partnerID=40&md5=1ec9cf1cd5ccd5db5f56762dc302eea3},
doi = {10.1007/978-981-15-1465-4_15},
issn = {18761100},
year = {2020},
date = {2020-01-01},
journal = {Lecture Notes in Electrical Engineering},
volume = {621},
pages = {135-147},
publisher = {Springer},
abstract = {“EGAT Eco Plus” is a smart city initiative of Electricity Generating Authority of Thailand (EGAT). To design the cloud infrastructure to support applications in the smart city, we need a modular design model which can dynamically adjust requirements and system parameters. This paper proposes the concept of smart city cloud controller which aims to provide so-called green service resource allocation by maximizing green i.e. renewable energy usage for data centers. Based on our formulated linear programming, our proposed SCCC model can provide green service resource allocation for data centers by maximizing the green energy usage. We evaluate the SCCC formulation with the green energy usage per each data center and overall of green energy usage in optimizing green metrics. Afterward, we compare our model with a well-known algorithm for solving the resource allocation problem i.e. round-robin. The model can be applied in the smart city whose data centers have different accessibility to on-site renewable energy sources. Besides, the proposed model can adjust parameters which are design criteria for green computing; the size of tasks, different power sources; and can be used as design guidelines for green computing in smart cities with more than one power source; grid, on-site renewable energy, battery energy storage. © Springer Nature Singapore Pte Ltd 2020.},
note = {cited By 0; Conference of 10th International Conference on Information Science and Applications, ICISA 2019 ; Conference Date: 16 December 2019 Through 18 December 2019; Conference Code:235259},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
“EGAT Eco Plus” is a smart city initiative of Electricity Generating Authority of Thailand (EGAT). To design the cloud infrastructure to support applications in the smart city, we need a modular design model which can dynamically adjust requirements and system parameters. This paper proposes the concept of smart city cloud controller which aims to provide so-called green service resource allocation by maximizing green i.e. renewable energy usage for data centers. Based on our formulated linear programming, our proposed SCCC model can provide green service resource allocation for data centers by maximizing the green energy usage. We evaluate the SCCC formulation with the green energy usage per each data center and overall of green energy usage in optimizing green metrics. Afterward, we compare our model with a well-known algorithm for solving the resource allocation problem i.e. round-robin. The model can be applied in the smart city whose data centers have different accessibility to on-site renewable energy sources. Besides, the proposed model can adjust parameters which are design criteria for green computing; the size of tasks, different power sources; and can be used as design guidelines for green computing in smart cities with more than one power source; grid, on-site renewable energy, battery energy storage. © Springer Nature Singapore Pte Ltd 2020.
3.
Tiennoy, S; Saivichit, C
Using a Distributed Roadside Unit for the Data Dissemination Protocol in VANET with the Named Data Architecture Journal Article
In: IEEE Access, vol. 6, pp. 32612-32623, 2018, ISSN: 21693536, (cited By 17).
@article{Tiennoy2018,
title = {Using a Distributed Roadside Unit for the Data Dissemination Protocol in VANET with the Named Data Architecture},
author = {S Tiennoy and C Saivichit},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85047618371&doi=10.1109%2fACCESS.2018.2840088&partnerID=40&md5=e9255854edc1fe2d9d8de4a4f1eb258f},
doi = {10.1109/ACCESS.2018.2840088},
issn = {21693536},
year = {2018},
date = {2018-01-01},
journal = {IEEE Access},
volume = {6},
pages = {32612-32623},
publisher = {Institute of Electrical and Electronics Engineers Inc.},
abstract = {Vehicular ad hoc network (VANET) has recently become one of the highly active research areas for wireless networking. Since VANET is a multi-hop wireless network with very high mobility and intermittent connection lifetime, it is important to effectively handle the data dissemination issue in this rapidly changing environment. However, the existing TCP/IP implementation may not fit into such a highly dynamic environment because the nodes in the network must often perform rerouting due to their inconsistency of connectivity. In addition, the drivers in the vehicles may want to acquire some data, but they do not know the address/location of such data storage. Hence, the named data networking (NDN) approach may be more desirable here. The NDN architecture is proposed for the future Internet, which focuses on the delivering mechanism based on the message contents instead of relying on the host addresses of the data. In this paper, a new protocol named roadside unit (RSU) assisted of named data network (RA-NDN) is presented. The RSU can operate as a standalone node [standalone RSU (SA-RSU)]. One benefit of deploying SA-RSUs is the improved network connectivity. This study uses the NS3 and SUMO software packages for the network simulator and traffic simulator software, respectively, to verify the performance of the RA-NDN protocol. To reduce the latency under various vehicular densities, vehicular transmission ranges, and number of requesters, the proposed approach is compared with vehicular NDN via a real-world data set in the urban area of Sathorn road in Bangkok, Thailand. The simulation results show that the RA-NDN protocol improves the performance of ad hoc communications with the increase in data received ratio and throughput and the decrease in total dissemination time and traffic load. © 2018 IEEE.},
note = {cited By 17},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Vehicular ad hoc network (VANET) has recently become one of the highly active research areas for wireless networking. Since VANET is a multi-hop wireless network with very high mobility and intermittent connection lifetime, it is important to effectively handle the data dissemination issue in this rapidly changing environment. However, the existing TCP/IP implementation may not fit into such a highly dynamic environment because the nodes in the network must often perform rerouting due to their inconsistency of connectivity. In addition, the drivers in the vehicles may want to acquire some data, but they do not know the address/location of such data storage. Hence, the named data networking (NDN) approach may be more desirable here. The NDN architecture is proposed for the future Internet, which focuses on the delivering mechanism based on the message contents instead of relying on the host addresses of the data. In this paper, a new protocol named roadside unit (RSU) assisted of named data network (RA-NDN) is presented. The RSU can operate as a standalone node [standalone RSU (SA-RSU)]. One benefit of deploying SA-RSUs is the improved network connectivity. This study uses the NS3 and SUMO software packages for the network simulator and traffic simulator software, respectively, to verify the performance of the RA-NDN protocol. To reduce the latency under various vehicular densities, vehicular transmission ranges, and number of requesters, the proposed approach is compared with vehicular NDN via a real-world data set in the urban area of Sathorn road in Bangkok, Thailand. The simulation results show that the RA-NDN protocol improves the performance of ad hoc communications with the increase in data received ratio and throughput and the decrease in total dissemination time and traffic load. © 2018 IEEE.
4.
Thun, S; Saivichit, C
Performance improvement of vehicular ad Hoc network environment by cooperation between SDN/openflow controller and IEEE 802.11p Journal Article
In: Journal of Telecommunication, Electronic and Computer Engineering, vol. 9, no. 2-6, pp. 95-99, 2017, ISSN: 21801843, (cited By 5).
@article{Thun2017,
title = {Performance improvement of vehicular ad Hoc network environment by cooperation between SDN/openflow controller and IEEE 802.11p},
author = {S Thun and C Saivichit},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85032906454&partnerID=40&md5=3ce5625496790af6c44987fe60ba2c52},
issn = {21801843},
year = {2017},
date = {2017-01-01},
journal = {Journal of Telecommunication, Electronic and Computer Engineering},
volume = {9},
number = {2-6},
pages = {95-99},
publisher = {Universiti Teknikal Malaysia Melaka},
abstract = {Vehicular communication has recently become an active research issue in both academic and industry. Vehicular Network, by nature, could possess potential problems in connectivity, intelligence, scalability and flexibility. Networking technology nowadays is moving toward to Software-Defined Networking (SDN) concept where the network is mainly separated into two planes; control plane and data plane. OpenFlow is the most popular open interface for SDN southbound API. In this paper, we proposed the SDN application over Vehicular ad hoc Network (VANET) environment. We believe that the emerging SDN technology and IEEE 802.11p can be used to increase the efficiency and to bridge the gaps in VANET application. We hope to exploit the benefit of SDN by adopting POX/OpenFlow controller to process and perform message routing. A centralized controller is the key player to enable communication between vehicles and roadside unit (RSU). We evaluated the proposed work based on three simulation indicators, such as packet delivery ratio, throughput and packet delay time.},
note = {cited By 5},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Vehicular communication has recently become an active research issue in both academic and industry. Vehicular Network, by nature, could possess potential problems in connectivity, intelligence, scalability and flexibility. Networking technology nowadays is moving toward to Software-Defined Networking (SDN) concept where the network is mainly separated into two planes; control plane and data plane. OpenFlow is the most popular open interface for SDN southbound API. In this paper, we proposed the SDN application over Vehicular ad hoc Network (VANET) environment. We believe that the emerging SDN technology and IEEE 802.11p can be used to increase the efficiency and to bridge the gaps in VANET application. We hope to exploit the benefit of SDN by adopting POX/OpenFlow controller to process and perform message routing. A centralized controller is the key player to enable communication between vehicles and roadside unit (RSU). We evaluated the proposed work based on three simulation indicators, such as packet delivery ratio, throughput and packet delay time.
5.
Aramvith, S; Aswakul, C; Saivichit, C; Prapinmongkolkarn, P; Aimdilokwong, A
NGN trial use and test site in Phuket, Thailand by national telecommunications commission (NTC) and Chula UniSearch Journal Article
In: Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, LNICST, vol. 46, pp. 622-625, 2011, ISSN: 18678211, (cited By 0; Conference of 6th International Conference on Testbeds and Research Infrastructures for the Development of Networks and Communities, TRIDENTCOM 2010 ; Conference Date: 18 May 2010 Through 20 May 2010; Conference Code:98879).
@article{Aramvith2011,
title = {NGN trial use and test site in Phuket, Thailand by national telecommunications commission (NTC) and Chula UniSearch},
author = {S Aramvith and C Aswakul and C Saivichit and P Prapinmongkolkarn and A Aimdilokwong},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-84885886930&doi=10.1007%2f978-3-642-17851-1_60&partnerID=40&md5=9e13655b2bfccec818a42bc7861de6af},
doi = {10.1007/978-3-642-17851-1_60},
issn = {18678211},
year = {2011},
date = {2011-01-01},
journal = {Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, LNICST},
volume = {46},
pages = {622-625},
address = {Berlin},
abstract = {National Telecommunication Commission of Thailand has initiated the pilot project which involved the trial and testbed of Next Generation Networks (NGNs) technology in Phuket, Thailand. This project consists of many new technologies implementation in the real environment. In order to implement the NGN technology successfully, we need to be able to summarize the outcomes of these deployment and prepare for improvement in the future. This project also extends the test to the communities in Phuket such as E- Learning applications. © Institute for Computer Sciences, Social Informatics and Telecommunications Engineering 2011.},
note = {cited By 0; Conference of 6th International Conference on Testbeds and Research Infrastructures for the Development of Networks and Communities, TRIDENTCOM 2010 ; Conference Date: 18 May 2010 Through 20 May 2010; Conference Code:98879},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
National Telecommunication Commission of Thailand has initiated the pilot project which involved the trial and testbed of Next Generation Networks (NGNs) technology in Phuket, Thailand. This project consists of many new technologies implementation in the real environment. In order to implement the NGN technology successfully, we need to be able to summarize the outcomes of these deployment and prepare for improvement in the future. This project also extends the test to the communities in Phuket such as E- Learning applications. © Institute for Computer Sciences, Social Informatics and Telecommunications Engineering 2011.
6.
Nguyen, T X My; Miyanaga, Y; Saivichit, C
Connectivity modeling analysis in flight-path based aviation ad hoc networks Journal Article
In: IEICE Transactions on Communications, vol. E94-B, no. 6, pp. 1606-1616, 2011, ISSN: 09168516, (cited By 4).
@article{MyNguyen2011,
title = {Connectivity modeling analysis in flight-path based aviation ad hoc networks},
author = {T X My Nguyen and Y Miyanaga and C Saivichit},
url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-79957947398&doi=10.1587%2ftranscom.E94.B.1606&partnerID=40&md5=a36168753b9998fc208f34918e3e4a26},
doi = {10.1587/transcom.E94.B.1606},
issn = {09168516},
year = {2011},
date = {2011-01-01},
journal = {IEICE Transactions on Communications},
volume = {E94-B},
number = {6},
pages = {1606-1616},
publisher = {Institute of Electronics, Information and Communication, Engineers, IEICE},
abstract = {In this paper, we propose a framework of connectivity analysis for aviation ad hoc networks on flight paths. First, a general analytical connectivity model for the common one-dimensional ad hoc network is newly developed. Then it is applied for modeling the connectivity of ad hoc networks among aircraft along flight paths where aircraft arrival process follows a Poisson distribution. Connectivity is expressed in terms of connectedness probability of two nodes in the network, connected distance, and network coverage extension factor. An exact closed form derivation of connectedness probability is proposed. The radical effect of mobility on the network connectedness of aircraft over a single flight path is analyzed. The network connectedness probability depends on node density and node distribution, which are derived from node arrival rate and node velocity. Based on these results, the proposed model is extended to the practical case of paths with multi-velocity air traffic classes. Using this model, the critical values of system parameters for the network of aircraft with certain connectivity requirements can be derived. It helps to evaluate network extension capability under the constraints of various system parameters. Copyright © 2011 The Institute of Electronics, Information and Communication Engineers.},
note = {cited By 4},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In this paper, we propose a framework of connectivity analysis for aviation ad hoc networks on flight paths. First, a general analytical connectivity model for the common one-dimensional ad hoc network is newly developed. Then it is applied for modeling the connectivity of ad hoc networks among aircraft along flight paths where aircraft arrival process follows a Poisson distribution. Connectivity is expressed in terms of connectedness probability of two nodes in the network, connected distance, and network coverage extension factor. An exact closed form derivation of connectedness probability is proposed. The radical effect of mobility on the network connectedness of aircraft over a single flight path is analyzed. The network connectedness probability depends on node density and node distribution, which are derived from node arrival rate and node velocity. Based on these results, the proposed model is extended to the practical case of paths with multi-velocity air traffic classes. Using this model, the critical values of system parameters for the network of aircraft with certain connectivity requirements can be derived. It helps to evaluate network extension capability under the constraints of various system parameters. Copyright © 2011 The Institute of Electronics, Information and Communication Engineers.