Sherief Hashima

Dr. Sherief Hashima

RIKEN-AIP Computational Learning Theory Team
orcid

Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

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

Representative Publications

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29 August 2022 in IEEE Access
Verified
Journal Article
Open access
AHAmira O. Hashesh
Amira O. Hashesh
Sherief HashimaSherief Hashima
Sherief Hashima
RMRokaia Mounir
Rokaia Mounir
Mostafa M. FoudaMostafa M. Fouda
Mostafa M. Fouda
KHKohei Hatano
Kohei Hatano
AEAdly S. Tag Eldien
Adly S. Tag Eldien
Recently, unmanned aerial vehicles (UAVs) communications gained significant concentration as a talented technology for future wireless communications using its remarkable advantages and broad applicability. Furthermore, UAV networks’ high complex configurations and designs encourage researchers to leverage relevant artificial intelligence (AI) techniques for better beyond fifth-generation (B5G)/sixth-generation (6G) services. This article summarizes AI-aided UAV solutions designated for forthcoming wireless networks. Besides, we deliver a comprehensive summary of machine learning (ML) approaches, including their applications and valuable contributions towards effective UAV network implementations, particularly advanced ML ones like bandits, federated learning (FL), meta-learning, etc. Finally, detailed UAV communication-related future research scopes and challenges is highlighted.

5 April 2022 in IEEE Wireless Communications Letters
Verified
Journal Article
Closed access
Ehab Mahmoud MohamedEhab Mahmoud Mohamed
Ehab Mahmoud Mohamed
Sherief HashimaSherief Hashima
Sherief Hashima
KHKohei Hatano
Kohei Hatano
Reconfigurable intelligent surface (RIS) and unmanned aerial vehicle (UAV) are anticipated as talented technologies to extend the range of millimeter wave (mmWave) communications. In this letter, a UAV equipped with RIS (UAV-RIS) is used to assist mmWave base station (BS) in covering users in hotspot areas. In this context, UAV should cover several high-capacity hotspots while minimizing its flying/hovering energy consumptions. Energy-aware multi-armed bandit (EA-MAB) algorithm is proposed as an effective online learning tool to handle this problem efficiently. By which, the UAV acts as the player trying to maximize its achievable rate, i.e., the reward, over selecting different hotspots in its trajectory, i.e., the arms of the bandit game. This is done while minimizing the energy/cost of the UAV flight from one hotspot to another over the time span of its battery life. Numerical analysis confirms the superior performance of the proposed EA-MAB algorithm over benchmarks.

29 June 2022 in IEEE Access
Verified
Journal Article
Open access
AGabdelrahman said ghoniem
abdelrahman said ghoniem
Sherief HashimaSherief Hashima
Sherief Hashima
Mostafa M. FoudaMostafa M. Fouda
Mostafa M. Fouda
MSMohamed Hassan Saad
Mohamed Hassan Saad
Worldwide, Nuclear Power Plants (NPPs) must have higher security protection and precise fault detection systems, especially underground power cable faults, to avoid causing national disasters and keep on safe national ratios of electricity production. Hence, this paper proposes an automatic, effective, and accurate Deep Learning (DL)-based fault classification and location technique for these cables via a One-dimensional Convolutional Neural Network (1D-CNN) and a Binary Support Vector Machine (BSVM). The proposed approach includes four main steps: data collection, feature extraction and reduction, fault detection, and fault classification and location. Signal collection from the underground cable’s sending end is performed via the Alternating Transient Program/Electromagnetic Transient Program (ATP/EMTP). Feature extraction and reduction are performed via Fractional Discrete Cosine Transform (FrDCT) and Singular Value Decomposition (SVD) methods. Fault detection is performed through leveraging BSVM with the linear Kernel method in the third step. Finally, this permits 1D-CNN to classify the fault type and locate it. Simulation results confirmed the efficiency of our proposed method, especially for 11kV underground cable faults, including different fault resistances and inception angles. Moreover, the proposed technique is applicable in real-time scenarios with a 99.6% accuracy rate, 0.15sec lowest execution time, and 0.095% maximum error rate for fault location at fractional factor ( $\alpha $ ) equals to 0.8.

30 April 2020 in IEEE Communications Letters
Verified
Journal Article
Closed access
Sherief HashimaSherief Hashima
Sherief Hashima
KHKohei Hatano
Kohei Hatano
ETEiji Takimoto
Eiji Takimoto
Ehab Mahmoud MohamedEhab Mahmoud Mohamed
Ehab Mahmoud Mohamed
The propagation characteristics of millimeter-wave (mmWaves), encourages its use in the device to device (D2D) communications for fifth-generation (5G) and future beyond 5G (B5G) networks. However, due to the use of beamforming training (BT), there is a tradeoff between exploring neighbor devices for best device selection and the required overhead. In this letter, using a tool of machine learning, joint neighbor discovery and selection (NDS) in mmWave D2D networks is formulated as a stochastic budget-constraint multi-armed bandit (MAB) problem. Hence, a modified Thomson sampling (TS) and variants of upper confidence bound (UCB) based algorithms are proposed to address the topic while considering the residual energies of the surrounding devices. Simulation analysis demonstrates the effectiveness of the proposed techniques over the conventional approaches concerning average throughput, energy efficiency, and network lifetime.

2 July 2021 in IEEE Systems Journal
Verified
Journal Article
Closed access
Basem M. ElhalawanyBasem M. Elhalawany
Basem M. Elhalawany
Sherief HashimaSherief Hashima
Sherief Hashima
KHKohei Hatano
Kohei Hatano
KWKaishun Wu
Kaishun Wu
Ehab Mahmoud MohamedEhab Mahmoud Mohamed
Ehab Mahmoud Mohamed
Millimeter wave (mmWave) communication has attracted considerable attention as a key technology for the next-generation wireless communications thanks to its exceptional advantages. MmWave leads the way to achieve a high transmission quality with directed narrow beams from source to multiple destinations by adopting different antenna beamforming (BF) techniques, which have a pivotal role in establishing and maintaining robust links. However, realizing such BF gains in practice requires overcoming several challenges, such as severe signal deterioration, hardware constraints, and design complexity. The elevated complexity of configuring mmWave BF vectors encourages researchers to leverage relevant machine learning (ML) techniques for better BF configurations deployment in 5G and beyond. In this article, we summarize mmWave BF strategies employed for future wireless networks. Then, we provide a comprehensive overview of ML techniques plus its applications and promising contributions toward efficient mmWave BF deployment. Furthermore, we discuss mmWave BF’s future research directions and challenges. Finally, we discuss a single and concurrent mmWave BF case study by applying multiarmed bandit to confirm the superiority of ML-based methods over conventional ones.

24 March 2022 in IEEE Internet of Things Journal
Verified
Journal Article
Closed access
Sherief HashimaSherief Hashima
Sherief Hashima
Mostafa M. FoudaMostafa M. Fouda
Mostafa M. Fouda
SSSadman Sakib
Sadman Sakib
ZZubair Fadlullah
Zubair Fadlullah
KHKohei Hatano
Kohei Hatano
XSXuemin Shen
Xuemin Shen
To handle the exponentially growing service expectations from mobile users and circumvent the band switching slow rate, device-to-device (D2D) communication is receiving much research attention in the Internet of Things (IoT). While the emerging D2D nodes can support heterogeneous frequency bands [radio frequency (RF) including 2.4 GHz/5 GHz wireless local area network (WLAN), 38-GHz millimeter wave (mmWave), and visible light communication (VLC)], the physical constraints (e.g., blocking) require the user devices to dynamically switch between the bands in order to avoid the loss of connectivity and throughput degradation. In this article, we investigate an effective online link selection in hybrid RF-VLC scenarios for direct user data handling. First, we model the multiband selection issue as a multiarmed bandit (MAB) problem. The source/relay node acts as a player who gambles to maximize its long-term feedback/reward via selecting suitable arms, i.e., available bands (WLAN, mmWave, or VLC). Then, we propose an online, energy-aware band selection (EABS) methodology by leveraging three theoretically guaranteed MAB techniques [upper confidence bound (UCB), Thompson sampling (TS), and minimax optimal stochastic strategy (MOSS)] to derive optimal band selection policies. Based on these adopted policies, we propose three algorithms, namely, EABS-UCB, EABS-TS, and EABS-MOSS, to implement the EABS strategy, respectively. Extensive simulations demonstrate our proposed algorithms’ superior performance compared to the traditional link selection schemes regarding energy efficiency, average throughput, and convergence rate. In particular, EABS-MOSS emerges as the best algorithm as it exhibits near-optimal performance due to its flexibility to both stochastic and adversarial environments.