Visible to the public Biblio

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2022-12-01
Lee, H., Lim, H., Lee, B..  2022.  Analysis of EV charging load impact on distribution network using XAI technique. CIRED Porto Workshop 2022: E-mobility and power distribution systems. 2022:167—170.
In order to solve the problems that may arise from the negative impact of EV charging loads on the power distribution network, it is very important to predict the distribution network variability according to EV charging loads. If appropriate facility reinforcement or system operation is made through evaluation of the impact of EV charging load, it will be possible to prevent facility failure in advance and maintain the power quality at a certain level, enabling stable network operation. By analysing the degree of change in the predicted load according to the EV load characteristics through the load prediction model, it is possible to evaluate the influence of the distribution network according to the EV linkage. This paper aims to investigate the effect of EV charging load on voltage stability, power loss, reliability index and economic loss of distribution network. For this, we transformed univariate time series of EV charging data into a multivariate time series using feature engineering techniques. Then, time series forecast models are trained based on the multivariate dataset. Finally, XAI techniques such as LIME and SHAP are applied to the models to obtain the feature importance analysis results.
2021-03-01
Hynes, E., Flynn, R., Lee, B., Murray, N..  2020.  An Evaluation of Lower Facial Micro Expressions as an Implicit QoE Metric for an Augmented Reality Procedure Assistance Application. 2020 31st Irish Signals and Systems Conference (ISSC). :1–6.
Augmented reality (AR) has been identified as a key technology to enhance worker utility in the context of increasing automation of repeatable procedures. AR can achieve this by assisting the user in performing complex and frequently changing procedures. Crucial to the success of procedure assistance AR applications is user acceptability, which can be measured by user quality of experience (QoE). An active research topic in QoE is the identification of implicit metrics that can be used to continuously infer user QoE during a multimedia experience. A user's QoE is linked to their affective state. Affective state is reflected in facial expressions. Emotions shown in micro facial expressions resemble those expressed in normal expressions but are distinguished from them by their brief duration. The novelty of this work lies in the evaluation of micro facial expressions as a continuous QoE metric by means of correlation analysis to the more traditional and accepted post-experience self-reporting. In this work, an optimal Rubik's Cube solver AR application was used as a proof of concept for complex procedure assistance. This was compared with a paper-based procedure assistance control. QoE expressed by affect in normal and micro facial expressions was evaluated through correlation analysis with post-experience reports. The results show that the AR application yielded higher task success rates and shorter task durations. Micro facial expressions reflecting disgust correlated moderately to the questionnaire responses for instruction disinterest in the AR application.
2019-08-05
Vanickis, R., Jacob, P., Dehghanzadeh, S., Lee, B..  2018.  Access Control Policy Enforcement for Zero-Trust-Networking. 2018 29th Irish Signals and Systems Conference (ISSC). :1-6.

The evolution of the enterprise computing landscape towards emerging trends such as fog/edge computing and the Industrial Internet of Things (IIoT) are leading to a change of approach to securing computer networks to deal with challenges such as mobility, virtualized infrastructures, dynamic and heterogeneous user contexts and transaction-based interactions. The uncertainty introduced by such dynamicity introduces greater uncertainty into the access control process and motivates the need for risk-based access control decision making. Thus, the traditional perimeter-based security paradigm is increasingly being abandoned in favour of a so called "zero trust networking" (ZTN). In ZTN networks are partitioned into zones with different levels of trust required to access the zone resources depending on the assets protected by the zone. All accesses to sensitive information is subject to rigorous access control based on user and device profile and context. In this paper we outline a policy enforcement framework to address many of open challenges for risk-based access control for ZTN. We specify the design of required policy languages including a generic firewall policy language to express firewall rules. We design a mechanism to map these rules to specific firewall syntax and to install the rules on the firewall. We show the viability of our design with a small proof-of-concept.

2018-02-14
Awad, A., Matthews, A., Qiao, Y., Lee, B..  2017.  Chaotic Searchable Encryption for Mobile Cloud Storage. IEEE Transactions on Cloud Computing. PP:1–1.

This paper considers the security problem of outsourcing storage from user devices to the cloud. A secure searchable encryption scheme is presented to enable searching of encrypted user data in the cloud. The scheme simultaneously supports fuzzy keyword searching and matched results ranking, which are two important factors in facilitating practical searchable encryption. A chaotic fuzzy transformation method is proposed to support secure fuzzy keyword indexing, storage and query. A secure posting list is also created to rank the matched results while maintaining the privacy and confidentiality of the user data, and saving the resources of the user mobile devices. Comprehensive tests have been performed and the experimental results show that the proposed scheme is efficient and suitable for a secure searchable cloud storage system.

2017-12-04
Johnston, B., Lee, B., Angove, L., Rendell, A..  2017.  Embedded Accelerators for Scientific High-Performance Computing: An Energy Study of OpenCL Gaussian Elimination Workloads. 2017 46th International Conference on Parallel Processing Workshops (ICPPW). :59–68.

Energy efficient High-Performance Computing (HPC) is becoming increasingly important. Recent ventures into this space have introduced an unlikely candidate to achieve exascale scientific computing hardware with a small energy footprint. ARM processors and embedded GPU accelerators originally developed for energy efficiency in mobile devices, where battery life is critical, are being repurposed and deployed in the next generation of supercomputers. Unfortunately, the performance of executing scientific workloads on many of these devices is largely unknown, yet the bulk of computation required in high-performance supercomputers is scientific. We present an analysis of one such scientific code, in the form of Gaussian Elimination, and evaluate both execution time and energy used on a range of embedded accelerator SoCs. These include three ARM CPUs and two mobile GPUs. Understanding how these low power devices perform on scientific workloads will be critical in the selection of appropriate hardware for these supercomputers, for how can we estimate the performance of tens of thousands of these chips if the performance of one is largely unknown?