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Progress in Natural Science:Materials international 2017年第3期27卷 316-325页

作者： Aamer A.M.Alfayyadh S.Lotfy A.A.Basfar mutasim i.khalil Radiation Technology Center Nuclear Science Research InstituteKing Abdulaziz City for Science and Technology(KACST) Polymer Chemistry Department National Center for Radiation Research and TechnologyAtomic Energy Authority Department of Chemistry Faculty of ScienceKing Saud University

Polyvinyl alcohol（PVA） of two molecular weights was used to prepare shape memory polymers based on chemical-crosslinking by *** chemical-crosslinking was done in the presence of 2-carboxyethvl acrylate oligomers（CEA） and nano-filler[multi-wall carbon nanotubes（MWCNT） and functionalized carbon nanotubes（MWCNT-NH;）]followed by radiation-induced *** analysis of the material revealed an increase in the gel fraction and a significant reduction in swelling of the nanocomposite material that was crosslinked with both glutaraldehyde and ionizing *** radiation crosslinked nanocomposites demonstrated approximately a 90%gelation over a range of 50-300 kGy irradiation *** scanning electron microscopy（SEM） analysis showed a homogeneous distribution of nanocomposites in the composite *** thermal properties of radiation crosslinked（PVA/CEA） and（PVA-CEA）-nano-fillers were investigated by a thermogravimetric analysis（TGA）.The mechanical properties were examined via dynamic mechanical analysis（DMA） which showed significant variation because of the addition of *** radiation crosslinked materials show good shape memory behavior that may be useful in many applications based on the range of temperatures at which Tan 8 appears.

关键词： Shape memory polymers Radiation Poly(vinyl alcohol) Nanocomposite materials

Enhancing active reconfigurable intelligent surface

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intelligent and Converged Networks 2022年第4期3卷 351-363页

作者： Muhammad i.khalil School of Electrical and Electronic Engineering University of Royal Melbourne Institute of Technology(RMIT)MelbourneVIC 3000Australia

A Reconfigurable intelligent Surface(RiS)panel comprises many independent Reflective Elements(REs).One possible way to implement an RiS is to use a binary passive load impedance connected to an antenna element to achieve the modulation of reflected radio *** RE reflects incoming waves(incident signal)by using on/off modulation between two passive loads and adjusting its phase using a Phase Shifter(PS).However,this modulation process reduces the amplitude of the reflected output signal to less than ***,recent RiS works have employed Reflection Amplifiers(RAs)to compensate for the losses incurred during the modulation ***,these systems only improve the reflection coefficient for a single modulation state,resulting in suboptimal RE ***,this paper proposes a strategy for optimising RE by continuously activating the RA regardless of the switching load *** performance of the proposed scheme is evaluated in two scenarios:(1)in the first scenario(Sc1),the RA only operates to compensate for high-impedance loads,and(2)in the second scenario(Sc2),the RA runs continuously regardless of the RE *** benchmark the performance of Sc1 and Sc2,various metrics are compared,including signal-to-noise ratio,insertion loss,noise figure,communication range,and power-added *** examples are provided to demonstrate the effectiveness of the proposed *** is found that the proposed system in Sc2 leads to better overall performance compared to Sc1 due to the increased gain of the RiS reflection.

关键词： reflection amplifiers reflection coefficient phase-shifter Reconfigurable intelligent Surface(RiS)

Secure Channel Estimation Using Norm Estimation Model for 5G Next Generation Wireless Networks

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Computers, Materials & Continua 2025年第1期82卷 1151-1169页

作者： khalil Ullah Song Jian Muhammad Naeem Ul Hassan Suliman Khan Mohammad Babar Arshad Ahmad Shafiq Ahmad Faculty of information Engineering and Automation Kunming University of Science and TechnologyKunming650500China Department of Computer Science Abbottabad University of Science and TechnologyHavelianAbbottabad22500Pakistan Department of Computing and Electronics Engineering Middle East CollegeMuscat124Oman Department of CS&iT Pak-Austria Fachhochschule Institute of Applied Sciences and Technology MangHaripur22621Pakistan industrial Engineering Department College of EngineeringKing Saud UniversityRiyadh11421Saudi Arabia

The emergence of next generation networks(NextG),including 5G and beyond,is reshaping the technological landscape of cellular and mobile *** networks are sufficiently scaled to interconnect billions of users and *** in academia and industry are focusing on technological advancements to achieve highspeed transmission,cell planning,and latency reduction to facilitate emerging applications such as virtual reality,the metaverse,smart cities,smart health,and autonomous *** continuously improves its network functionality to support these *** input multiple output(MiMO)technology offers spectral efficiency,dependability,and overall performance in *** article proposes a secure channel estimation technique in MiMO topology using a norm-estimation model to provide comprehensive insights into protecting NextG network components against adversarial *** technique aims to create long-lasting and secure NextG networks using this extended *** viability of MiMO applications and modern Ai-driven methodologies to combat cybersecurity threats are explored in this ***,the proposed model demonstrates high performance in terms of reliability and accuracy,with a 20%reduction in the MalOut-RealOut-Diff metric compared to existing state-of-the-art techniques.

关键词： Next generation networks massive mimo communication network artificial intelligence 5G adversarial attacks channel estimation information security

Sources of Nigerian Architecture in the 21st Century

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Journal of Civil Engineering and Architecture 2019年第6期13卷 401-407页

作者： Moukhtar M.Mai Sani i.khalil Department of Architectural Technology School of Environmental StudiesFederal Polytechnic NasarawaNasarawa State252976Nigeria Department of Architecture Faculty of Arts&Environmental SciencesBayero UniversityKano 729725Nigeria

Nigeria,the home of the largest conglomeration of blacks in the world,deserves its unique architectural *** variety of vernacular built environment seems to hold promise to that *** architecture across Nigeria’s geographical clusters has demonstrated a thorough response to the climate,local technology and socio-economic parameters in which they *** advent of colonialism,the spread of islam in Africa,and the end of slave trade,impacted tremendously on the options available to developers and master builders over the *** review paper identifies the prospective sources of evolving the country’s unique spatial identity and architectural language by critically exploring the determinant and moderating factors of the development of ethno-regional built environment for the *** life style and the divergent historical circumstances of the nation’s core subdivisions readily suggest the devolution regional *** paper argues that a national identity could be forged through a five-tier synthesis of architectural strategies,to positively integrate form,space,and order imaginatively to fit user“genius loci”,*** of *** application of the courtyard within the family compound(groups of dwelling units sharing common services),serves physical,social,and economic functions ***,the essence of traditional style has to be cherished dearly,to ensure cultural heritage conservation of the *** could be concluded that despite the gradual replacement of traditional building practices with modern trends;core cultural values like hierarchic selective interaction(privacy)afforded by the courtyard housing system,seem to be retained as consistent features of Nigeria’s build environment,which must be jealously guarded.

关键词： National identity vernacular architecture form space culture

THE DRAG EXERTED BY AN OBLATE ROTATiNG ATMOSPHERE ON AN ARTiFiCiAL SATELLiTE

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Applied Mathematics and Mechanics(English Edition) 2002年第9期23卷 1016-1028页

作者： KH.i.khalil National Research institute of Astronomy and Geophsics-Helwan Cairo Egypt

A theory is formulated for the motion of an artificial satellite under the joint effects of Earth oblateness and atmospheric drag. The Hamilton ' s equations of motion are derived including the zonal harmonics of the geopotential up to J4 and the drag accelerations. The atmospheric model is an oblate rotating model in which the atmospheric rotation lags behind that of the Earth as the increasing distance from the Earth. The drag free problem is first solved via two canonical transformations to eliminate in succession the short and long period terms. An operator D is then defined and used to formulate the drag acceleration in terms of the double primed variables expressing the solution of the drag-free problem.

关键词： oblateness the Hamiltonian Lie transform

Correction:Deep Learning-Enhanced Brain Tumor Prediction via Entropy-Coded BPSO in CiELAB Color Space

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Computers, Materials & Continua 2025年第1期82卷 1461-1461页

作者： Mudassir khalil Muhammad imran Sharif Ahmed Naeem Muhammad Umar Chaudhry Hafiz Tayyab Rauf Adham E.Ragab Department of Computer Engineering Bahauddin Zakariya UniversityMultan60000Pakistan Department of Computer Science Kansas State UniversityManhattanKS 66506USA Department of Computer Science University of Management and TechnologyLahore54000Pakistan independent Researcher BradfordBD80HSUK industrial Engineering Department Collage of EngineeringKing Saud UniversityP.O.Box 800Riyadh11421Saudi Arabia

in the article“Deep Learning-Enhanced Brain Tumor Prediction via Entropy-Coded BPSO in CiELAB Color Space”by Mudassir khalil,Muhammad imran Sharif,Ahmed Naeem,Muhammad Umar Chaudhry,Hafiz Tayyab Rauf,Adham *** Computers,Materials&Continua,2023,Vol.77,No.2,pp.2031–***:10.32604/cmc.2023.043687,URL:https://***/cmc/v77n2/54831,there was an error regarding the affiliation for the author Hafiz Tayyab *** of“Centre for Smart Systems,Ai and Cybersecurity,Staffordshire University,Stoke-on-Trent,ST42DE,UK”,the affiliation should be“independent Researcher,Bradford,BD80HS,UK”.

关键词： Deep Code CiELAB

Laser Polarization Orientations in(e,2e)Reactions in Atoms

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Chinese Physics Letters 2015年第8期32卷 62-65页

作者： Ajana i. Makhoute A. khalil D. UFR de Physique du Rayonnement et des interactions Laser-Matière Faculté des SciencesUniversité Moulay Ismail

Second-order Born calculations are performed to investigate the triple differential cross sections of coplanar asymmetric laser-assisted （e, 2e） collisions for hydrogen and helium targets. The incident electron is considered to be dressed by the laser field in a nonperturbative manner by choosing the Volkov solutions in both the initial and final channels. Detailed calculations of the scattering amplitudes are performed using the Sturmian basis expansion. The state of the ejected electron is described by a Coulomb-Volkov wave function. Two geometries are investigated in which the laser polarization vector is either parallel to the incident momentum of the projectile or parallel to the momentum transfer. Our numerical results show that, in the low energy range, these two laser polarization orientations give the same shape and the same order of magnitude of laser-assisted ionization cross sections of helium and hydrogen targets.

关键词： Laser Polarization Orientations in e,2e)Reactions in Atoms

Tungsten ion source under double-pulse laser ablation system

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Chinese Physics B 2017年第9期26卷 285-296页

作者： Ahmed Asaad i.khalil Ashraf i Hafez Mahmoud E Elgohary Mohamed A Morsy Department of Laser Sciences and interactions National Institute of Laser Enhanced SciencesCairo UniversityGiza 12613Egypt Central Laboratory of Ministry of Electricity CairoEgypt Atomic Research Center Atomic Energy AuthorityCairo 13759Egypt Department of Nuclear Engineering Jordan University of Science and Technology IrbidJordan Department of Chemistry King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

New tungsten ion source is produced by using single and double-pulse laser ablation system. Combined collinear Nd：YAG laser beams（266＋1064 nm） are optimized to focus on the sample in air. Optimization of the experimental parameters is achieved to enhance the signal-to-noise ratio of the emission spectra. The velocity distribution of the emitted plasma cloud is carefully measured. The influences of the potential difference between the bias electrodes, laser wavelength and intensity on the current signal are also studied. The results show that the increase in the tungsten ion velocity under the double-pulse lasers causes the output current signal to increase by about three folds. The electron density and temperature are calculated by using the Stark-broadened line profile of tungsten line and Boltzmann plot method of the upper energy levels, respectively. The signal intensity dependence of the tungsten ion angular distribution is also analyzed. The results indicate that the double-pulse laser ablation configuration is more potent technique for producing more metal ion source deposition, thin film formation, and activated plasma-facing component material.

关键词： tungsten ion beam double-pulse lasers ablation system laser ablation system optical instrumentation

Robust Stabilization of Non-minimum Phase Switched Nonlinear Systems with Uncertainty

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Journal of Systems Science & Complexity 2020年第2期33卷 289-311页

作者： khalil Jouili Laboratory of Advanced Systems Polytechnic School of Tunisia(EPT) B.P.7432078 MarsaTunisia

This paper investigates the problem of robust stabilization of a class of switched nonlinear system with uncertain dynamics where each subsystem represents a non-minimum *** authors first construct a stabilizing sliding mode controller for each subsystem to stabilize individually its own unstable internal ***,a switching strategy is introduced to select the most appropriate diffeomorphism through an infinity of *** conditions are specifically given for the exponential stability and the exponential upper bound of the trajectory of the switched subsystem,which guarantees the global asymptotical stability of the resulting switched ***,the proposed control approach can improvemore the transient state,compared to a feedback linearization based on only one *** studies illustrate the effectiveness of the suggested approach.

关键词： Exponential stability sliding mode control switching control uncertain non-minimum phase systems

Mechanical wet-milling and subsequent consolidation of ultra-fine Al_2O_3-(ZrO_2+3%Y_2O_3) bioceramics by using high-frequency induction heat sintering

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中国有色金属学会会刊：英文版 2007年第1期17卷 21-26页

作者： khalil Abdelrazek khalil Sug Won KiM Division of Advanced Materials Engineering RIAMD Chonbuk National University

Alumina/zirconia composites were synthesized by wet-milling technique and rapid consolidation with high frequency induction heat sintering(HFiHS). The starting materials were a mixture of alumina micro-powder (80%, volume fraction) and 3YSZ nano-powders (20%). The mixtures were optimized for good sintering behaviors and mechanical properties. Nano-crystalline grains are obtained after 24 h milling. The nano-structured powder compacts are then processed to full density at different temperatures by HFiHS. Effects of temperature on the mechanical and microstructure properties were studied. Al2O3-3YSZ composites with higher mechanical properties and small grain size are successfully developed at relatively low temperatures through this technique.

关键词：生物陶瓷烧结工艺高频诱导微观结构机械性能