Browsing by Author "El Shafie, Ahmed"
Now showing items 1-20 of 28
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Achievable Rates of Buffer-Aided Full-Duplex Gaussian Relay Channels
El Shafie, Ahmed; Sultan, Ahmed; Krikidis, Ioannis; Al-Dhahir, Naofal; Hamila, Ridha ( Institute of Electrical and Electronics Engineers Inc. , 2017 , Article)We derive closed-form expressions for the achievable rates of a buffer-aided full-duplex (FD) multiple-input multiple-output Gaussian relay channel. The FD relay still suffers from residual self-interference (RSI) after ... -
Application of a definitive screening design for the synthesis of a charge-transfer complex of sparfloxacin with tetracyanoethylene: Spectroscopic, thermodynamic, kinetics, and DFT computational studies
El-Shafie, Ahmed S.; Khashan, Areej W.; Husseina, Yasser H. A.; El-Azazy, Marwa ( Royal Society of Chemistry , 2019 , Article)Herein, a spectrochemical approach was adopted to study the charge-transfer (CT) complexation of sparfloxacin (SFX) with tetracyanoethylene (TCNE). In this study, a three-level design of experiments (DOE) involving a ... -
Application of Plackett-Burman Design for Spectrochemical Determination of the Last-Resort Antibiotic, Tigecycline, in Pure Form and in Pharmaceuticals: Investigation of Thermodynamics and Kinetics.
El-Shafie, Ahmed S; Yousef, Aseel; El-Azazy, Marwa ( MDPI , 2022 , Article)Tigecycline (TIGC) reacts with 7,7,8,8-tetracyanoquinodimethane (TCNQ) to form a bright green charge transfer complex (CTC). The spectrum of the CTC showed multiple charge transfer bands with a major peak at 843 nm. The ... -
Application of Samarium- and Terbium-Sensitized Luminescence via a Multivariate-Based Approach for the Determination of Orbifloxacin
Al-Hashimi, Nessreen; El-Shafie, Ahmed S.; Jumaa, Asmaa; El-Azazy, Marwa ( Hindawi , 2022 , Article)A lanthanide-based optical sensor has been developed for the sensitive and reliable spectrofluorometric determination of the fluoroquinolone antibiotic orbifloxacin (ORLX). Reaction of ORLX and two lanthanide metal ions, ... -
Cooperative cognitive relaying under primary and secondary quality of service satisfaction
El Shafie, Ahmed; Khattab, Tamer ( Institute of Electrical and Electronics Engineers Inc. , 2014 , Conference Paper)This paper proposes a new cooperative protocol which involves cooperation between primary and secondary users. We consider a cognitive setting with one primary user (PU) and multIPle secondary users (SUs). The time resource ... -
Energy-efficient cooperative relaying protocol for full-duplex cognitive radio users and delay-aware primary users
El Shafie, Ahmed; Khattab, Tamer ( Institute of Electrical and Electronics Engineers Inc. , 2015 , Conference Paper)This paper considers a network in which a primary user (PU) may cooperate with a cognitive radio (CR) user for transmission of its data packets. The PU is assumed to be a buffered terminal operating in a time-slotted ... -
Exploiting sparsity of relay-assisted cognitive radio networks
El Shafie, Ahmed; Al-dhahir, Naofal; Hamila, Ridha ( IEEE , 2015 , Conference Paper)We propose a novel protocol for secondary users based on compressive sensing principles. The secondary user assigned to one of the primary frequency bands is aided by a set of nearby secondary users, which we refer to as ... -
Impact of the Wireless Network's PHY Security and Reliability on Demand-Side Management Cost in the Smart Grid
El Shafie, Ahmed; Niyato, Dusit; Hamila, Ridha; Al-Dhahir, Naofal ( Institute of Electrical and Electronics Engineers Inc. , 2017 , Article)We investigate the impact of the wireless network's physical layer (PHY) security and reliability on demand-side management operation in the smart grid. We assume that consumers communicate their energy demands with the ... -
Maximum Secondary Stable Throughput of a Cooperative Secondary Transmitter-Receiver Pair: Protocol Design and Stability Analysis
El Shafie, Ahmed; Khattab, Tamer; El-Keyi, Amr; Nafie, Mohammed ( Institute of Electrical and Electronics Engineers Inc. , 2016 , Conference Paper)In this paper, we investigate the impact of cooperation between a secondary transmitter-receiver pair and a primary transmitter on the maximum stable throughput of the primary-secondary network. Each transmitter, either ... -
Maximum throughput of a cooperative energy harvesting cognitive radio user
El Shafie, Ahmed; Khattab, Tamer ( Institute of Electrical and Electronics Engineers Inc. , 2014 , Conference Paper)In this paper, we investigate the maximum throughput of a saturated rechargeable secondary user (SU) sharing the spectrum with a primary user (PU). The SU harvests energy packets (tokens) from the environment with a certain ... -
Maximum throughput of a secondary user cooperating with an energy-aware primary user
El Shafie, Ahmed; Sultan, Ahmed; Khattab, Tamer ( IEEE Computer Society , 2014 , Conference Paper)This paper proposes a cooperation protocol between a secondary user (SU) and a primary user (PU) which dedicates a free frequency subband for the SU if cooperation results in energy saving. Time is slotted and users are ... -
On orthogonal band allocation for multiuser multiband cognitive radio networks: Stability analysis
El Shafie, Ahmed; Khattab, Tamer ( Institute of Electrical and Electronics Engineers Inc. , 2015 , Article)In this work, we study the problem of band allocation of Mi buffered (i.e., with data queues capable of storing incoming traffic packets) secondary users (SUs) to Mp primary frequency bands licensed to (owned by) Mp buffered ... -
On the delay/throughput-security tradeoff in wiretap TDMA networks with buffered nodes
El Shafie, Ahmed; Al-Dhahir, Naofal; Ding, Zhiguo; Hamila, Ridha ( IEEE , 2019 , Article)In this paper, we investigate the tradeoff between security and throughput and between security and queuing delay in wiretap time-division multiple access (TDMA) networks. We derive a simple relationship, characterized by ... -
On the Design of a Relay-Assisted Network
El Shafie, Ahmed; Khattab, Tamer; Sultan, Ahmed; Poor, H. Vincent ( Institute of Electrical and Electronics Engineers Inc. , 2015 , Article)A relay network composed of a source, a set of relays, and a destination is considered. A queueing framework is proposed, in which each node maintains a buffer to store its incoming traffic. An optimization-based formulation ... -
Potato Peels as an Adsorbent for Heavy Metals from Aqueous Solutions: Eco-Structuring of a Green Adsorbent Operating Plackett-Burman Design
El-Azazy, Marwa; El-Shafie, Ahmed S.; Issa, Ahmed A.; Al-Sulaiti, Maetha; Al-Yafie, Jawaher; Shomar, Basem; Al-Saad, Khalid... more authors ... less authors ( Hindawi Limited , 2019 , Article)Treatment of wastewater is becoming a concern of an increasing prominence. Trace amounts of toxic metalloids and heavy metals (HMs) would contaminate large volumes of water. Being present as traces, removal of these ... -
Probabilistic band-splitting for a buffered cooperative cognitive terminal
El Shafie, Ahmed; Sultan, Ahmed; Khattab, Tamer ( Institute of Electrical and Electronics Engineers Inc. , 2014 , Conference Paper)In this paper, we propose a cognitive protocol that involves cooperation between the primary and secondary users. In addition to its own queue, the secondary user (SU) has a queue to store, and then relay, the undelivered ... -
Protocol design and stability analysis of cooperative cognitive radio users
El Shafie, Ahmed; Khattab, Tamer; Poor, H. Vincent ( Institute of Electrical and Electronics Engineers Inc. , 2016 , Conference Paper)A single cognitive radio transmitter-receiver pair shares the spectrum with two primary users communicating with their respective receivers. Each primary user has a local traffic queue, whereas the cognitive user has three ... -
Relay-Assisted Primary and Secondary Transmissions in Cognitive Radio Networks
El Shafie, Ahmed; Khattab, Tamer; Sultan Salem, Ahmed ( Institute of Electrical and Electronics Engineers Inc. , 2016 , Article)We assume a set of cognitive relay nodes that assists both primary and secondary transmissions in a time-slotted cognitive radio networks. To regulate the channel access of the various nodes in the network, we propose an ... -
Secure AF Relaying in Power-Constrained UAV Networks
Samara, Lutfi; AlAbbasi, Abubakr O.; El Shafie, Ahmed; Hamila, Ridha; Al-Dhahir, Naofal ( IEEE , 2021 , Conference Paper)This paper proposes a secure amplify-and-forward (AF) relaying scheme in unmanned aerial vehicle (UAV) networks while accounting for the power consumption limitations of UAVs. Since a UAV's battery life is limited, we ... -
Securing Untrusted RF-EH Relay Networks Using Cooperative Jamming Signals
El Shafie, Ahmed; Mabrouk, Asma; Tourki, Kamel; Al-Dhahir, Naofal; Hamila, Ridha ( Institute of Electrical and Electronics Engineers Inc. , 2017 , Article)We propose a new scheme to secure a wireless-powered untrusted cooperative-communication network, where a legitimate source node (Alice) transmits her information messages to a legitimate destination node (Bob) through the ...