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Massless Dirac perturbations of black holes in f(Q)gravity:quasinormal modes and a weak deflection angle

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Communications in Theoretical Physics 2024年第9期76卷 73-82页

作者： ahmad al-Badawi Sohan Kumar Jha Department of Physics Al-Hussein Bin Talal UniversityPO Box 2071111Ma'anJordan Department of Physics Chandernagore CollegeChandernagoreHooghlyWest BengalIndia

This article considers a static and spherical black hole(BH)in f(Q)gravity.f(Q)gravity is the extension of symmetric teleparallel general relativity,where both curvature and torsion are vanishing and gravity is described by *** this study,we investigate the possible implications of quasinormal mode(QNM)modified Hawking spectra and deflection angles generated by the *** Wentzel–Kramers–Brillouin method is used to solve the equations of motion for massless Dirac perturbation fields and explore the impact of the nonmetricity parameter(Q_(0)).Based on the QNM computation,we can ensure that the BH is stable against massless Dirac perturbations and as Q_(0)increases the oscillatory frequency of the mode *** then discuss the weak deflection angle in the weak field limit *** compute the deflection angle up to the fourth order of approximation and show how the nonmetricity parameter affects *** find that the Q_(0)parameter reduces the deflection angle.

关键词： black holes in f(Q)gravity massless Dirac perturbations quasinormal modes deflection angle

Shadows and weak gravitational lensing for black holes within Einstein-Maxwell-scalar theory

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Chinese Physics C 2024年第9期48卷 234-243页

作者： ahmad al-Badawi Mirzabek alloqulov Sanjar Shaymatov Bobomurat Ahmedov Department of Physics Al-Hussein Bin Talal UniversityP.O.Box:20Ma'an 71111Jordan Institute of Fundamental and Applied Research National Research University TIIAMEKori Niyoziy 39Tashkent 100000Uzbekistan University of Tashkent for Applied Sciences Str.Gavhar 1Tashkent 100149Uzbekistan Institute for Theoretical Physics and Cosmology Zhejiang University of TechnologyHangzhou 310023China Western Caspian University Baku AZ1001Azerbaijan

In this study,we investigated the optical properties of charged black holes within the Einstein-Maxwellscalar(EMS)*** evaluated the shadow cast by these black holes and obtained analytical solutions for both the radius of the photon sphere and that of the *** observed that black hole parametersγandβboth influence the shadow of black *** also found that the photon sphere and shadow radius increase as a consequence of the presence of the parameterγ.Interestingly,the shadow radius decreases first and then remains unchanged owing to the impact of the parameterβ.Finally,we analyzed the weak gravitational lensing and total magnification of lensed images around black *** found that the charge of the black holes and the parameterβboth have a significant impact,reducing the deflection ***,the same behavior for the total magnification was observed,also as a result of the effect of the charge of the black holes and the parameterβ.

关键词： Einstein Maxwell gravity shadow gravitational weak lensing

A regular MOG black hole's impact on shadows and gravitational weak lensing in the presence of a quintessence field

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Communications in Theoretical Physics 2024年第8期76卷 91-102页

作者： ahmad al-Badawi Sanjar Shaymatov Mirzabek alloqulov Anzhong Wang Department of Physics Al-Hussein Bin Talal UniversityPO Box:2071111Ma’anJordan Institute for Theoretical Physics and Cosmology Zhejiang University of TechnologyHangzhou 310023China Tashkent State Technical University Tashkent 100095Uzbekistan University of Tashkent for Applied Sciences Str.Gavhar 1Tashkent 100149Uzbekistan New Uzbekistan University Movarounnahr Street 1Tashkent 100000Uzbekistan Institute of Fundamental and Applied Research National Research University TIIAMEKori Niyoziy 39Tashkent 100000Uzbekistan GCAP-CASPER Physics DepartmentBaylor UniversityWacoTX 76798-7316United States of America

We investigate the impact of the modified gravity(MOG)field and the quintessence scalar field on horizon evolution,black hole(BH)shadow and the weak gravitational lensing around a static spherically symmetric *** first begin to write the BH metric associated with the MOG parameter and quintessence scalar *** then determine the BH shadow and obtain numerical solutions for the photon sphere and shadow *** show that the MOG(α)and the quintessence(c)parameters have a significant impact on the BH shadow and photon *** on the analysis,we further show that the combined effects of the MOG parameter and quintessence field can increase the values of BH shadow and photon sphere *** also obtain constraints on the BH parameters by applying the observational data of Sgr A^(★)and M87^(★).Finally,we consider the weak deflection angle of BH within the context of the Gauss-Bonnet theorem(GBT)and show that the combined effects of the MOG and quintessence parameters do make the value of the deflection angle increase,and find this remarkable property is in good agreement with the physical meaning of both parameters that can maintain the strong gravitational field in the surrounding environment of a BH.

关键词： modified gravity shadows gravitational weak lensing quintessence field

Cloud Datacenter Selection Using Service Broker Policies:A Survey

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 1-41页

作者： Salam al-E’mari Yousef Sanjalawe ahmad al-Daraiseh Mohammad Bany Taha Mohammad aladaileh Department of Information Security Faculty of ITUniversity of PetraAmman11196Jordan Department of Cybersecurity School of ITAmerican University of Madaba(AUM)Amman11821Jordan Department of Computer Science School of ITAmerican University of Madaba(AUM)Amman11821Jordan Department of Data Science and Artificial Intelligence School of ITAmerican University of Madaba(AUM)Amman11821Jordan

Amid the landscape of Cloud Computing(CC),the Cloud Datacenter(DC)stands as a conglomerate of physical servers,whose performance can be hindered by bottlenecks within the realm of proliferating CC services.A linchpin in CC’s performance,the Cloud Service Broker(CSB),orchestrates DC *** to adroitly route user requests with suitable DCs transforms the CSB into a bottleneck,endangering service *** tackle this,deploying an efficient CSB policy becomes imperative,optimizing DC selection to meet stringent Qualityof-Service(QoS)*** numerous CSB policies,their implementation grapples with challenges like costs and *** article undertakes a holistic review of diverse CSB policies,concurrently surveying the predicaments confronted by current *** foremost objective is to pinpoint research gaps and remedies to invigorate future policy ***,it extensively clarifies various DC selection methodologies employed in CC,enriching practitioners and researchers *** synthetic analysis,the article systematically assesses and compares myriad DC selection *** analytical insights equip decision-makers with a pragmatic framework to discern the apt technique for their *** summation,this discourse resoundingly underscores the paramount importance of adept CSB policies in DC selection,highlighting the imperative role of efficient CSB policies in optimizing CC *** emphasizing the significance of these policies and their modeling implications,the article contributes to both the general modeling discourse and its practical applications in the CC domain.

关键词： Cloud computing cloud service broker datacenter selection quality-of-service user request

Influence of erbium on structural,and charged particles,photons,and neutrons shielding properties of Ba_(1-x)Er_(x)SnO_(3) perovskite ceramics

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Journal of Rare Earths 2024年第4期42卷 724-732页

作者： M.K.h.hamad Nidal Dwaikat M.H.A.Mhareb M.I.Sayyed R.M.hamad Y.S.M.alajerami M.A.almessiere Gameel Saleh ahmad Hussein alomari K.A.Ziq Department of Basic Sciences School of Social and Basics SciencesAl Hussein Technical UniversityKing Abdullah II St 242Amman11831Jordan Department of Physics College of Engineering and PhysicsInterdisciplinary Research Center for Advanced MaterialsKing Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Basic and Applied Scientific Research Center Imam Abdulrahman Bin Faisal UniversityP0.Box 1982Dammam31441Saudi Arabia Department of Physics Faculty of ScienceIsra UniversityAmman11622Jordan Department of Nuclear Medicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Arabia Medical Imaging Department Applied Medical Sciences FacultyAl Azhar University-Gaza CityPo.Box 1277Palestine Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box1982Dammam 31441Saudi Arabia Department of Biomedical Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Energy&Minerals Regulatory Commission Amman11821Jordan

Five perovskite ceramics samples of Ba_(1-x)Er_(x)SnO_(3) with x=0.00,0.05,0.10,0.15,and 0.20 were synthesized using the conventional solid-state reaction *** prepared samples were characterized by X-ray diffraction(XRD),Fourier transforms infrared(FTIR),and UV-Vis *** shielding properties against ionizing radiation were also *** XRD analysis shows the perovskite cubic structure as the major phase in all *** FTIR reveals a distinctive band around 614-620 cm^(-1) ascribed to the antisymmetric O-Sn-O ***-Vis spectroscopy was used to determine the bandgap according to diffuse reflectance,and the results display a fixed enhancement in the bandgap from 3.2 to 3.3 eV for all ***-ray shielding properties of the synthesized samples were experimentally measured and compared with XCOM computational *** relative differences(Δ,%)between experimental and theo retical values are low and fall within the 0.446%-7.10%*** addition of Er leads to the enhanced density,neutron,and gamma shielding *** contrast,charged particles’shielding parameters gradually reduce with rising Er *** results suggest that Ba_(1-x)Er_(x)SnO_(3) samples can be used in different radiation shielding applications.

关键词： Perovskite Ceramics Gamma ray shielding Mass stopping power Rare earths

Fostering firm innovativeness:Understanding the sequential relationships between human resource practices,psychological empowerment,innovative work behavior,and firm innovative capability

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International Journal of Innovation Studies 2024年第1期8卷 76-91页

作者： Ruba Sami al Daboub Amro al-Madadha ahmad Samed al-Adwan Business Administration Department Princess Sumaya University for TechnologyAmmanJordan Department of Business Technology Business SchoolHourani Center for Applied Scientific ResearchAl-Ahliyya Amman UniversityAmmanJordan

This study investigated the relationships between human resource(HR)practices,employee psychological empowerment,employee innovative work behavior,and firm innovation capability in the context of the Information and Communication Technology(ICT)sector in *** the Social Exchange Theory(SET)as a guiding framework,this study explored how employee psychological empowerment and innovative work behavior mediated the influence of HR practices on a firm’s innovative *** on extensive data collected from ICT organizations in Jordan,our analysis had several key findings.A significant positive correlation between HR practices and psychological empowerment was *** design emerged as the most influential factor affecting psychological empowerment,whereas compensation had a weaker ***,we established that psychological empowerment significantly enhanced innovative work behavior,underscoring its role as a catalyst for innovative work behavior within the ***,our study supported the theory that psychological empowerment influenced a firms’innovation capabilities,emphasizing the pivotal role of employee empowerment in driving firm-level innovation in the Jordanian ICT *** findings provide insights for academic and practical audiences,clarifying how HR practices,employee psychological empowerment,and innovative work behavior collectively influenced firm innovation capability within the unique context of the Jordanian ICT sector.

关键词： Human resources practices Psychological empowerment Innovative work behavior Firm innovative capability Social exchange theory Job design

Results Involving Partial Differential Equations and Their Solution by Certain Integral Transform

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1593-1616页

作者： Rania Saadah Mohammed Amleh ahmad Qazza Shrideh al-Omari Ahmet Ocak Akdemir Department of Mathematics Faculty of ScienceZarqa UniversityZarqa13110Jordan Department of Mathematics Faculty of ScienceAl-Balqa Applied UniversityAmman11134Jordan Department of Mathematics Faculty of Science and LettersAgri Ibrahim莈鏴n UniversityAgri04100Turkey

In this study,we aimto investigate certain triple integral transformand its application to a class of partial *** discuss various properties of the new transformincluding inversion, linearity, existence, scaling andshifting, etc. Then,we derive several results enfolding partial derivatives and establish amulti-convolution ***, we apply the aforementioned transform to some classical functions and many types of partial differentialequations involving heat equations,wave equations, Laplace equations, and Poisson equations ***,wedraw some figures to illustrate 3-D contour plots for exact solutions of some selected examples involving differentvalues in their variables.

关键词： ARA transform double ARA transform triple ARA transform partial differential equations integral transform

Orbit Weighting Scheme in the Context of Vector Space Information Retrieval

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Computers, Materials & Continua 2024年第7期80卷 1347-1379页

作者： ahmad Ababneh Yousef Sanjalawe Salam Fraihat Salam al-E’mari Hamzah alqudah Department of Computer Science Faculty of Information TechnologyAmerican University of MadabaAmman11821Jordan Department of Cybersecurity Faculty of Information TechnologyAmerican University of MadabaAmman11821Jordan Artificial Intelligence Research Center(AIRC) College of Engineering and Information TechnologyAjman UniversityP.O.Box 346Ajman13306United Arab Emirates Information Security Department Faculty of Information TechnologyUniversity of PetraAmman11196Jordan Department of Data Science and Artificial Intelligence Faculty of Information TechnologyAmerican University of MadabaAmman11821Jordan

This study introduces the Orbit Weighting Scheme(OWS),a novel approach aimed at enhancing the precision and efficiency of Vector Space information retrieval(IR)models,which have traditionally relied on weighting schemes like tf-idf and *** conventional methods often struggle with accurately capturing document relevance,leading to inefficiencies in both retrieval performance and index size *** proposes a dynamic weighting mechanism that evaluates the significance of terms based on their orbital position within the vector space,emphasizing term relationships and distribution patterns overlooked by existing *** research focuses on evaluating OWS’s impact on model accuracy using Information Retrieval metrics like Recall,Precision,InterpolatedAverage Precision(IAP),andMeanAverage Precision(MAP).Additionally,we assessOWS’s effectiveness in reducing the inverted index size,crucial for model *** compare OWS-based retrieval models against others using different schemes,including tf-idf variations and *** reveal OWS’s superiority,achieving a 54%Recall and 81%MAP,and a notable 38%reduction in the inverted index *** highlights OWS’s potential in optimizing retrieval processes and underscores the need for further research in this underrepresented area to fully leverage OWS’s capabilities in information retrieval methodologies.

关键词： Information retrieval orbit weighting scheme semantic text analysis Tf-Idf weighting scheme vector space model

Exploring the thermophysical properties of natural deep eutectic solvents for gas capture applications: a comprehensive review

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Green Chemical Engineering 2024年第3期5卷 307-338页

作者： ahmad al-Bodour Noor alomari alberto Guti errez Santiago Aparicio Mert Atilhan Department of Chemical and Paper Engineering Western Michigan University Department of Chemistry University of Burgos Faculty of Sciences

With the intensifying challenge of global warming driven largely by anthropogenic activities, effective greenhouse gas capture techniques are critical. This paper focuses on the role of deep eutectic solvents(DES) as promising agents for such capture at the source. We review the key DES-based methods for greenhouse gas capture, drawing conclusions from a thorough analysis of the existing literature. In particular, we examine the effect of DES structure on gas solubilities and explore the mechanism of gas solubility in DES through molecular simulation. We present a synthesis of state-of-the-art results in this area, assessing the potential of DES as an alternative to current industrial gas capture methods. Furthermore, we propose future research directions for the design of novel DES tailored to more specific applications.

关键词： Global warming Climate change Deep eutectic solvents Gas capture Gas separation