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Power Reallocation and Complexity Enhancement for Beyond 4G Systems

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China Communications 2019年第6期16卷 114-128页

作者： Omar daoud Communications and Electronics Engineering Department Philadelphia University

Competitiveness in the modern wireless systems’provided services is a key factor in the development,in addition to the adaptation to/harmonization of user ***,this paper discussed the quality of services from the point of view of the need for supporting the needed data *** this purpose,a benchmark based on Multi-Antenna Multiband Orthogonal Frequency Division Multiplexing has been proposed to compatible with Ultra-Wideband systems such as the fifth generation based *** order to enhance the system quality of service,the structure of the ultra-wideband system’s main stage;namely Orthogonal Frequency Division Multiplexing has been modified by imposing a low complexity designed Haar-wavelets stage instead of the fast Fourier transform *** is in addition to reallocate the transmitted power in order to reduce the effect of one of the main drawbacks that is found in the Orthogonal Frequency Division Multiplexing;namely the peak-to-average power ratio problem.A MATLAB simulation has been performed in order to validate the propositions that have been made based on six different performance *** a result,the new propositions were achieved our targets by reducing the system’s complexity in terms of mathematical operations and by giving promising results in managing the transmitted ***,the effectiveness of such work has been verified and compared with four different work in the literature。

关键词： multi antennas-multiband wireless PAPR Haar-DWT power reallocation ACLR EVM

On a biseparability criterion of bipartite qudit state

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Chinese Physics B 2019年第8期28卷 42-49页

作者： B Benzimoun M daoud LPHE-Modeling and Simulation Faculty of SciencesUniversity Mohammed ⅤRabatMorocco Department of Physics Faculty of Sciences-Ain ChockUniversity Hassan ⅡCasablancaMorocco Abdus Salam International Centre for Theoretical Physics TriesteItaly

In this paper,we propose a new approach to tackle the separability problem for bipartite qudit *** is based on the Majorana representation which allows to represent a N-spinors(qudit)as a symmetric state of N spin-1/*** also discuss how we can exploit such representation and the notion of the biseparability of multipartite qubit states in the sense to establish new criteria of the separability problem based on the PPT and concurrence.

关键词： separability bipartite qubit state partial separability Majorana representation

Seasonal variations of polybrominated flame retardants bound to car dust under Mediterranean climate

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Journal of Environmental Sciences 2018年第8期30卷 124-132页

作者： Yael Dubowski maisa Inibtawi David M.Broday Faculty of Civil and Environmental Engineering Technion - Israel Institute of Technology

Polybrominated diphenyl ethers（PBDEs） are commercial flame retardants that have been commonly used in vehicle interior to reduce fire-related hazards. Due to high temperatures and intense insolation that can be attained inside cars parked in the sun, additive PBDEs are prone to leach out and attach to in-vehicle dust, as well as to photo-debrominate. This study examines seasonal variations of concentrations of three common PBDE congeners（BDE-47, BDE-99 and BDE-209） in car dust in Israel. The overall concentrations of these BDEs ranged from 1 to 29 μg/g, and were higher in the summer than in the winter（average of 10.2 and5.3 μg/g, respectively）. Congener-specific concentrations showed distinct seasonal pattern,representing the interplay between leaching, evaporation and photodebromination. Photolysis of the three congeners, while adsorbed on glass filters and exposed to solar radiation, revealed first order kinetics with debromination rates on the order of 10-2/min. Hence, seasonal variations of the meteorological conditions were found to affect the in-vehicle PBDE concentrations, and are therefore expected also to affect the exposure of passengers to PBDEs.

关键词： Polybrominated diphenyl ether (PBDE) Flame retardants Car dust Debromination Mediterranean climate Photolysis

mRNA vaccines: Past, present, future

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Asian Journal of Pharmaceutical Sciences 2022年第4期17卷 491-522页

作者： Mia Karam Georges daoud Biomedical Engineering Program Maroun Semaan Faculty of Engineering and ArchitectureBeirut 11072020Lebanon Department of Biochemistry and Molecular Genetics Faculty of MedicineBeirut 11072020Lebanon Department of Anatomy Cell Biologyand Physiological SciencesFaculty of MedicineAmerican University of BeirutBeirut 11072020Lebanon

mRNA vaccines have emerged as promising alternative platforms to conventional *** ease of production,low cost,safety profile and high potency render them ideal candidates for prevention and treatment of infectious diseases,especially in the midst of *** challenges that face in vitro transcribed RNA were partially amended by addition of tethered adjuvants or co-delivery of naked mRNA with an adjuvanttethered ***,it wasn’t until recently that the progress made in nanotechnology helped enhance mRNA stability and delivery by entrapment in novel delivery systems of which,lipid *** continuous advancement in the fields of nanotechnology and tissue engineering provided novel carriers for mRNA vaccines such as polymeric nanoparticles and *** studies have shown the advantages of adopting mRNA vaccines for viral diseases and cancer in animal and human ***-amplifying mRNA is considered today the next generation of mRNA vaccines and current studies reveal promising *** review provides a comprehensive overview of mRNA vaccines used in past and present studies,and discusses future directions and challenges in advancing this vaccine platform to widespread clinical use.

关键词： mRNA vaccine Virus Cancer Nanoparticles COVID-19

SIMAD:Secure Intelligent Method for IoT-Fog Environments Attacks Detection

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Computers, Materials & Continua 2022年第2期70卷 2727-2742页

作者： Wided Ben daoud Sami Mahfoudhi NTS’Com Research Unit SfaxTunisia Department of MIS CBEQassim UniversityBuraidahAl QassimKSA

The Internet of Thing IoT paradigm has emerged in numerous domains and it has achieved an exponential ***,alongside this advancement,IoT networks are facing an ever-increasing rate of security risks because of the continuous and rapid changes in network *** order to overcome these security challenges,the fog system has delivered a powerful environment that provides additional resources for a more improved data ***,because of the emerging of various breaches,several attacks are ceaselessly emerging in IoT and Fog ***,the new emerging applications in IoT-Fog environment still require novel,distributed,and intelligent security models,controls,and *** addition,the ever-evolving hacking techniques and methods and the expanded risks surfaces have demonstrated the importance of attacks detection *** proves that even advanced solutions face difficulties in discovering and recognizing these small variations of *** fact,to address the above problems,Artificial Intelligence(AI)methods could be applied on the millions of terabytes of collected information to enhance and optimize the processes of IoT and fog *** this respect,this research is designed to adopt a new security scheme supported by an advanced machine learning algorithm to ensure an intelligent distributed attacks detection and a monitoring process that detects malicious attacks and updates threats signature databases in IoTFog *** evaluated the performance of our distributed approach with the application of certain machine *** experiments show that the proposed scheme,applied with the Random Forest(RF)is more efficient and provides better accuracy(99.50%),better scalability,and lower false alert *** this regard,the distribution character of our method brings about faster detection and better learning.

关键词： Attack detection Fog IoT network machine learning distributed mechanism

A Novel Lightweight Image Encryption Scheme

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Computers, Materials & Continua 2023年第4期75卷 2137-2153页

作者： Rawia Abdulla Mohammed maisa’a Abid Ali Khodher Ashwak Alabaichi Department of Computer Science University of TechnologyBaghdadIraq Department of Biomedical Engineering University of KerbalaKerbalaIraq

Encryption algorithms are one of the methods to protect dataduring its transmission through an unsafe transmission medium. But encryptionmethods need a lot of time during encryption and decryption, so itis necessary to find encryption algorithms that consume little time whilepreserving the security of the data. In this paper, more than one algorithmwas combined to obtain high security with a short implementation time. Achaotic system, DNA computing, and Salsa20 were combined. A proposed5D chaos system was used to generate more robust keys in a Salsa algorithmand DNA computing. Also, the confusion is performed using a new *** proposed chaos system achieves three positive Lyapunov *** results demonstrate of the proposed scheme has a sufficient peak signalto-noise ratio, a low correlation, and a large key space. These factors makeit more efficient than its classical counterpart and can resist statistical anddifferential attacks. The number of changing pixel rates (NPCR) and theunified averaged changed intensity (UACI) values were 0.99710 and UACI33.68. The entropy oscillates from 7.9965 to 7.9982 for the tested encryptedimages. The suggested approach is resistant to heavy attacks and takes lesstime to execute than previously discussed methods, making it an efficient,lightweight image encryption scheme. The method provides lower correlationcoefficients than other methods, another indicator of an efficient imageencryption system. Even though the proposed scheme has useful applicationsin image transmission, it still requires profound improvement in implementingthe high-intelligence scheme and verifying its feasibility on devices with theInternet of Things (IoT) enabled.

关键词： Chaotic system lightweight confusion diffusion encryption Salsa20

Modified Adomian decomposition method for solving the problem of boundary layer convective heat transfer

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Propulsion and Power Research 2018年第3期7卷 231-237页

作者： Yassir daoud Ahmed A.Khidir Faculty of Mathematical Sciences and Statistics Alneelain UniversityAlgamhoria StreetP.O.Box 12702KhartoumSudan

In this paper,we apply a new modification of the Adomian decomposition method for solving the problem of boundary layer convective heat transfer with viscous dissipation and low pressure gradient over a at *** technique is based on the standard Adomian decomposition method and the Chebyshev pseudospectral *** are made between the pro-posed technique,the standard Adomian decomposition method,and the numerical solutions to demonstrate the applicability,validity,and high accuracy of the present *** results demonstrate that the new modification is more efficient and converges faster than the Adomian decomposition method.

关键词： Adomian decomposition method Chebyshev spectral method Boundary layer convective

Quantum correlations and entanglement in coupled optomechanical resonators with photon hopping via Gaussian interferometric power analysis

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Chinese Physics B 2024年第5期33卷 204-211页

作者： Y.Lahlou B.Maroufi M.daoud LPHE-MS Department of PhysicsFaculty of SciencesMohammed V UniversityRabatMorocco LPMS Department of PhysicsFaculty of SciencesIbn Tofail UniversityKénitraMorocco

Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum ***,for quantum systems prepared in pure states,it is difficult to differentiate between quantum entanglement and quantum ***,this indistinguishability is no longer holds for mixed *** contribute to a better understanding of this differentiation,we have explored a simple model for both generating and measuring these quantum *** study concerns two macroscopic mechanical resonators placed in separate Fabry–Pérot cavities,coupled through the photon hopping *** system offers a comprehensively way to investigate and quantify quantum correlations beyond entanglement between these mechanical *** key ingredient in analyzing quantum correlation in this system is the global covariance *** forms the basis for computing two essential metrics:the logarithmic negativity(E_(N)^(m))and the Gaussian interferometric power(P_(G)^(m)).These metrics provide the tools to measure the degree of quantum entanglement and quantum correlations,*** study reveals that the Gaussian interferometric power(P_(G)^(m))proves to be a more suitable metric for characterizing quantum correlations among the mechanical modes in an optomechanical quantum system,particularly in scenarios featuring resilient photon hopping.

关键词： quantum correlations entanglement Gaussian interferometric power logarithmic negativity optomechanics photon hopping

Finite temperature thermophysical properties of MgCu intermetallic compound from quasi-harmonic Debye model

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Journal of Magnesium and Alloys 2019年第2期7卷 335-344页

作者： Salah daoud Nadhira Bioud P.K.Saini Laboratoire Matériaux et Systèmes Electroniques UniversitéMohamed Elbachir El Ibrahimi de Bordj Bou ArreridjBordj Bou Arreridj 34000Algérie Laboratoire d’Optoélectronique et Composants UniversitéFerhat Abbas Sétif 1Sétif 19000Algérie Facultédes sciences et de la technologie UniversitéMohamed Elbachir El Ibrahimi de Bordj Bou ArreridjBordj Bou Arreridj 34000Algérie Department of Physics Government CollegeHansiHaryana 125033India

The influence of pressure and temperature on the thermodynamic properties of MgCu intermetallic compound was investigated by quasi-harmonic Debye model *** equation of state(EoS)parameters has performed using plane-wave pseudopotential(PW-PP)approach in the framework of the density functional theory(DFT)and the generalized gradient approximation(GGA)for the exchange-correlation *** results agree well with other data of the *** finite temperature thermophysical properties under pressure up to 16 GPa and high temperature up to 800 K,respectively were *** results of the thermophysical properties are also agree very well with other data of the literature,where for example at ambient temperature,the deviation between our obtained value(11.05 Cal mol^(−1)K^(−1))of C V,and the theoretical value(11.21 Cal mol^(−1)K^(−1))reported in the literature is only around 1.44%.The finite temperature thermophysical properties were found varied monotonically with either temperature or *** with other materials previously studied,similar behaviors were observed.

关键词： Thermophysical properties Quasi-harmonic Debye model MgCu intermetallic compound High-pressure