Kushan Sudheera Kalupahana Liyanage

Dr. Kushan Sudheera Kalupahana Liyanage

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Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

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

Representative Publications

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4 January 2024 in IEEE Sensors Journal
Verified
Journal Article
Closed access
DMDeepika Mohan
Deepika Mohan
Duaa Zuhair Al-hamidDuaa Zuhair Al-hamid
Duaa Zuhair Al-hamid
Peter ChongPeter Chong
Peter Chong
Kushan Sudheera Kalupahana LiyanageKushan Sudheera Kalupahana Liyanage
Kushan Sudheera Kalupahana Liyanage
Jairo GutierrezJairo Gutierrez
Jairo Gutierrez
HLHui Li
Hui Li
Globally, the number of falls among the elderly is rising, particularly among those 60 and older. An important contributing element to these falls is the fact that elderly people who live alone are not regularly supervised. A significant number of claims are filed for injuries caused by falls in the elderly, and at times these falls result in fatalities. Therefore, well-founded, and practical e-health technologies are critical for elder care, particularly for individuals who live alone. One of the emerging and rapid-growing technologies like Artificial Intelligence would be an excellent companion for them to continuously monitor their health condition and prevent falls. This review paper compares various research, surveys, studies, and experiments conducted on elderly fall prevention utilizing Artificial Intelligence and other technologies such as Internet of Things (IoT), Sensor, Radio Detection and Ranging (RADAR), Infrared Radiation (IR) and Hardware technologies. It has been identified that in real time and long-term monitoring without human intervention, AI-IoT technology will be the best solution for fall prevention in older adults.

25 January 2019 in IEEE Transactions on Vehicular Technology
Verified
Journal Article
Closed access
Kushan Sudheera Kalupahana LiyanageKushan Sudheera Kalupahana Liyanage
Kushan Sudheera Kalupahana Liyanage
MMMaode Ma
Maode Ma
Peter ChongPeter Chong
Peter Chong
The dynamic nature of vehicular networks imposes a lot of challenges in multihop data transmission as links are vulnerable in their existence due to associated mobility of vehicles. Thus, packets frequently find it difficult to get through to the destination due to the limited lifetimes of links. The conventional broadcasting based vehicular ad-hoc network (VANET) routing protocols struggle to accurately analyze the link dynamicity due to the unavailability of global information and inefficiencies in their route discovering schemes. However, with the recently emerged software defined vehicular network (SDVN) paradigm, link stability can be better scrutinized pertaining to the availability of global network information. Thus, in this paper, we introduce an optimization based novel packet routing scheme with a source routing based flow instantiation (FI) operation for SDVN. The routing framework closely analyzes the stability of links in selecting the routes and the problem is formulated as a minimum cost capacitated flow problem. Furthermore, an incremental packet allocation scheme is proposed to solve the routing problem in a less time complexity. The objective is to find multiple shortest paths which are collectively stable enough to deliver a given number of packets. The FI scheme efficiently delivers and caches flow information in the required nodes with a reduced extent of communication with the control plane. With the help of realistic simulation, we show that the proposed routing framework excels in terms of the performance over the existing routing schemes of both SDVN and conventional VANET.

1 February 2021 in IEEE Internet of Things Journal
Verified
Journal Article
Closed access
Kushan Sudheera Kalupahana LiyanageKushan Sudheera Kalupahana Liyanage
Kushan Sudheera Kalupahana Liyanage
DDDinil Mon Divakaran
Dinil Mon Divakaran
RSRhishi Pratap Singh
Rhishi Pratap Singh
MGMohan Gurusamy
Mohan Gurusamy
The fast-growing Internet-of-Things (IoT) market has opened up a large threat landscape, given the wide deployment of IoT devices in both consumer and commercial spaces. Attacks on IoT devices generally consist of multiple stages and are dispersed spatially and temporally. These characteristics make it challenging to detect and identify the attack stages using solutions that tend to be localized in space and time. In this work, we present Adept, a distributed framework to detect and identify the individual attack stages in a coordinated attack. Adept works in three phases. First, network traffic of IoT devices is processed locally for detecting anomalies with respect to their benign profiles. Any alert corresponding to a potential anomaly is sent to a security manager, where aggregated alerts are mined, using frequent itemset mining (FIM), for detecting patterns correlated across both time and space. Finally, using both alert-level and pattern-level information as features, we employ a machine learning approach to identify individual attack stages in the generated alerts. We carry out extensive experiments, with emulated and realistic network traffic; the results demonstrate the effectiveness of the proposed framework in terms of its ability in attack-stage detection and identification.

14 September 2022 in Sensors
Verified
Journal Article
Open access
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Dhammike Piyumal Madhurajith HerathDhammike Piyumal Madhurajith Herath
Dhammike Piyumal Madhurajith Herath
WWWeraniyagoda Arachchilage Sahanaka Anuththara Weraniyagoda
Weraniyagoda Arachchilage Sahanaka Anuththara Weraniyagoda
RRRajapakshage Thilina Madhushan Rajapaksha
Rajapakshage Thilina Madhushan Rajapaksha
Patikiri Arachchige Don Shehan Nilmantha WijesekaraPatikiri Arachchige Don Shehan Nilmantha Wijesekara
Patikiri Arachchige Don Shehan Nilmantha Wijesekara
Kushan Sudheera Kalupahana LiyanageKushan Sudheera Kalupahana Liyanage
Kushan Sudheera Kalupahana Liyanage
Peter ChongPeter Chong
Peter Chong
Aphasia is a type of speech disorder that can cause speech defects in a person. Identifying the severity level of the aphasia patient is critical for the rehabilitation process. In this research, we identify ten aphasia severity levels motivated by specific speech therapies based on the presence or absence of identified characteristics in aphasic speech in order to give more specific treatment to the patient. In the aphasia severity level classification process, we experiment on different speech feature extraction techniques, lengths of input audio samples, and machine learning classifiers toward classification performance. Aphasic speech is required to be sensed by an audio sensor and then recorded and divided into audio frames and passed through an audio feature extractor before feeding into the machine learning classifier. According to the results, the mel frequency cepstral coefficient (MFCC) is the most suitable audio feature extraction method for the aphasic speech level classification process, as it outperformed the classification performance of all mel-spectrogram, chroma, and zero crossing rates by a large margin. Furthermore, the classification performance is higher when 20 s audio samples are used compared with 10 s chunks, even though the performance gap is narrow. Finally, the deep neural network approach resulted in the best classification performance, which was slightly better than both K-nearest neighbor (KNN) and random forest classifiers, and it was significantly better than decision tree algorithms. Therefore, the study shows that aphasia level classification can be completed with accuracy, precision, recall, and F1-score values of 0.99 using MFCC for 20 s audio samples using the deep neural network approach in order to recommend corresponding speech therapy for the identified level. A web application was developed for English-speaking aphasia patients to self-diagnose the severity level and engage in speech therapies.

1 February 2023 in Sensors
Verified
Journal Article
Open access
PDF file
Patikiri Arachchige Don Shehan Nilmantha WijesekaraPatikiri Arachchige Don Shehan Nilmantha Wijesekara
Patikiri Arachchige Don Shehan Nilmantha Wijesekara
Kushan Sudheera Kalupahana LiyanageKushan Sudheera Kalupahana Liyanage
Kushan Sudheera Kalupahana Liyanage
NSNadeesha Sandamali
Nadeesha Sandamali
Peter ChongPeter Chong
Peter Chong
A Software Defined Vehicular Network (SDVN) is a new paradigm that enhances programmability and flexibility in Vehicular Adhoc Networks (VANETs). There exist different architectures for SDVNs based on the degree of control of the control plane. However, in vehicular communication literature, we find that there is no proper mechanism to collect data. Therefore, we propose a novel data collection methodology for the hybrid SDVN architecture by modeling it as an Integer Quadratic Programming (IQP) problem. The IQP model optimally selects broadcasting nodes and agent (unicasting) nodes from a given vehicular network instance with the objective of minimizing the number of agents, communication delay, communication cost, total payload, and total overhead. Due to the dynamic network topology, finding a new solution to the optimization is frequently required in order to avoid node isolation and redundant data transmission. Therefore, we propose a systematic way to collect data and make optimization decisions by inspecting the heterogeneous normalized network link entropy. The proposed optimization model for data collection for the hybrid SDVN architecture yields a 75.5% lower communication cost and 32.7% lower end-to-end latency in large vehicular networks compared to the data collection in the centralized SDVN architecture while collecting 99.9% of the data available in the vehicular network under optimized settings.

9 September 2021 in IEEE Transactions on Intelligent Transportation Systems
Verified
Journal Article
Closed access
NSNadeesha Sandamali
Nadeesha Sandamali
RSRong Su
Rong Su
Kushan Sudheera Kalupahana LiyanageKushan Sudheera Kalupahana Liyanage
Kushan Sudheera Kalupahana Liyanage
YZYicheng Zhang
Yicheng Zhang
Inherent uncertainties of the air transportation system (ATS) can induce unexpected anomalies in its operations such as deviations in flight schedules, sudden imbalances of demands and capacities, etc.. Current air traffic flow management (ATFM) models rarely consider both demand and capacity uncertainties in their algorithms, and generally focus on minimizing the flight delays under deterministic constraints. Thus, to bridge this gap, we propose a framework for en-route ATFM while scrutinizing uncertainties in en-route capacity and demand and their imbalance, via a chance constraint based probabilistic approach. The proposed framework plays a key role in ensuring the safety of the overall ATS in terms of maintaining the safety separation between flights and constraining the capacity of the sectors as well. Moreover, flight level assignments scheme is proposed based on the Base of Aircraft Data (BADA) of the European Organization for the Safety of Air Navigation (EUROCONTROL) with the objective of minimizing the fuel consumption. The model further minimizes the overall expected delay of the system using the control actions of ground holding, speed control, rerouting, and flight cancellations. At the implementation stage, two phases of ATFM as pre-tactical and tactical are considered, in which the former focuses on generating optimal trajectories and the latter focuses on real-time updates of flight plans. The computational complexity is reduced by shrinking the feasibility region and decomposing the problem into maximum weighted independent sets. The experimental results of realistic large-scale problems demonstrate the effectiveness and computational feasibility of our ATFM framework.