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The stability of some Viable stars and Electromagnetic Field

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Chinese Physics Letters 2016年第7期33卷 25-27页

作者： M.Azam s.A.Mardan M.A.rehman Division of science and Technology University of EducationTownship Campus Department of Mathematics University of the Management and Technology

We examine the impact of electromagnetic field on the stability of compact stars corresponding to embedded class one metric using the concept of cracking. For this purpose, we develop the generalized hydrostatic equi- librium equation for charged perfect fluid distribution of compact stars and perturb it by means of local density perturbation scheme to check the stability of inner matter configuration. We investigate the cracking of Her X-I, PsR 1937＋21, PsR J 1614-2230, PsR J 0348＋0432 and B.X J 1856-37. We conclude that PsR J 0348＋0432 and RX J 1856-37 exhibit cracking when charge is introduced on these astrophysical objects.

关键词： of in et it on PsR The stability of some Viable stars and Electromagnetic Field for

Fruit Leaf Diseases Classification: A Hierarchical Deep Learning Framework

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计算机、材料和连续体（英文） 2023年第4期75卷 1179-1194页

作者： samra rehman muhammad Attique Khan Majed Alhaisoni Ammar Armghan Fayadh Alenezi Abdullah Alqahtani Khean Vesal Yunyoung Nam Department of Computer science HITEC UniversityTaxila47080Pakistan Computer sciences Department College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Electrical Engineering College of EngineeringJouf UniversitySakakah72311Saudi Arabia College of Computer Engineering and sciences Prince Sattam bin Abdulaziz UniversityAl-Kharj16242Saudi Arabia Department of ICT Convergence Soonchunhyang UniversityAsan31538Korea

Manual inspection of fruit diseases is a time-consuming and costly because it is based on naked-eye *** authors present computer vision techniques for detecting and classifying fruit leaf *** of computer vision techniques are preprocessing original images for visualization of infected regions,feature extraction from raw or segmented images,feature fusion,feature selection,and *** following are the major challenges identified by researchers in the literature:(i)lowcontrast infected regions extract irrelevant and redundant information,which misleads classification accuracy;(ii)irrelevant and redundant information may increase computational time and reduce the designed model’s *** paper proposed a framework for fruit leaf disease classification based on deep hierarchical learning and best feature *** the proposed framework,contrast is first improved using a hybrid approach,and then data augmentation is used to solve the problem of an imbalanced *** next step is to use a pre-trained deep model named Darknet53 and fine-tune ***,deep transfer learning-based training is carried out,and features are extracted using an activation function on the average pooling ***,an improved butterfly optimization algorithm is proposed,which selects the best features for classification using machine learning *** experiment was carried out on augmented and original fruit datasets,yielding a maximum accuracy of 99.6%for apple diseases,99.6%for grapes,99.9%for peach diseases,and 100%for cherry *** overall average achieved accuracy is 99.7%,higher than previous techniques.

关键词： Fruit diseases data augmentation contrast enhancement deep learning improved butterfly optimization

Potential Inhibitory Effect of Vitamins Against COVID-19

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Computers, Materials & Continua 2021年第1期66卷 707-714页

作者： Kashaf Junaid sumera Qasim Humaira Yasmeen Hasan Ejaz Abdullah Alsrhani muhammad Ikram Ullah Fahad Ahmad Abdul rehman Department of Clinical Laboratory sciences College of Applied Medical SciencesJouf UniversitySakakaAl JoufSaudi Arabia College of Pharmacy Jouf UniversitySakakaAl JoufSaudi Arabia Department of Microbiology and Molecular Genetics The Women’s UniversityMultanPakistan Department of Computer sciences Kinnaird College for WomenLahorePakistan Department of Microbiology and Molecular Genetics University of the PunjabLahorePakistan

Coronavirus disease 2019(COVID-19)is a current pandemic that has affected more than 195 countries *** this severe acute respiratory syndrome coronavirus 2(sARs-CoV-2)pandemic,when treatment strategies are not yet clear and vaccines are not available,vitamins are an excellent choice to protect against this viral *** rationale behind this study was to examine the inhibitory effect of vitamins B,C,and D against the main protease of sARsCoV-2 and angiotensin-converting enzyme 2(ACE2),which have critical rolesin the immune *** docking,performed by using MOE-Dock of the Chemical Computing Group,was used to understand the *** vitamins all docked within the active sites of the Mpro(PDB ID:6LU7)and ACE2 receptor proteins(PDB ID:6VW1).Vitamins B and C delivered maximum energy scores against both targets,while vitamin D displayed a binding energy score of−7.9532 kcal/mol for M^(pro) and−7.9297 for *** efficiency of all three vitamins is higher than the binding energy score of chloroquine(−6.889 kcal/mol),which is now under clinical *** use of vitamins is beneficial,being immune system restorative,and they also act as anti-COVID *** the potential beneficial effects of vitamin B and C are revealed through docking studies,further clinical trials are required for the validation of these results.

关键词： sARs-CoV-2 vitamins docking antivirals chemical computing

Context and Machine Learning Based Trust Management Framework for Internet of Vehicles

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Computers, Materials & Continua 2021年第9期68卷 4125-4142页

作者： Abdul rehman Mohd Fadzil Hassan Yew Kwang Hooi muhammad Aasim Qureshi Tran Duc Chung Rehan Akbar sohail safdar Computer and Information science Department Centre for Research and Data Science(CeRDaS)Universiti Teknologi PETRONAS32610Seri IskandarPerak Darul RidzuanMalaysia Department of Computer science Bahria UniversityPakistan Computing Fundamental Department FPT UniversityHoa Lac Hi-Tech ParkHanoiVietnam Department of Information systems Uiversiti Tunku Abdul RahmanMalaysia Information Technology Department College of IT AHLAI UniversityBahrain

Trust is one of the core components of any ad hoc network security *** management(TM)has always been a challenging issue in a vehicular *** such developing network is the Internet of vehicles(IoV),which is expected to be an essential part of smart *** originated from the merger of Vehicular ad hoc networks(VANET)and the Internet of things(IoT).security is one of the main barriers in the on-road IoV *** security standards are insufficient to meet the extremely dynamic and rapidly changing IoV *** plays a vital role in ensuring security,especially during vehicle to vehicle *** networks,having a unique nature among other wireless ad hoc networks,require dedicated efforts to develop trust *** TM schemes are inflexible and *** scenarios and limited parameters are the basis for existing TM models that are not suitable for vehicle *** vehicular network requires agile and adaptive solutions to ensure security,especially when it comes to critical *** vehicle network’s wireless nature increases its attack surface and exposes the network to numerous security ***,internet involvement makes it more vulnerable to *** proposed TM framework is based on context-based cognition and machine learning to be best suited to IoV *** learning is the best solution to utilize the big data produced by vehicle *** handle the uncertainty Bayesian machine learning statistical model is *** proposed framework can adapt scenarios dynamically and infer using the maximum possible parameter *** results indicated better performance than existing TM ***,for future work,a high-level machine learning model is proposed.

关键词： Internet of vehicles(IoV) trust management(TM) vehicular ad hoc network(VANET) machine learning context awareness bayesian learning

Adaptive Fuzzy Logic Controller for Harmonics Mitigation Using Particle swarm Optimization

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Computers, Materials & Continua 2022年第6期71卷 4275-4293页

作者： Waleed Rafique Ayesha Khan Ahmad Almogren Jehangir Arshad Adnan Yousaf Mujtaba Hussain Jaffery Ateeq Ur rehman muhammad shafiq Department of Electrical&Computer Engineering COMSATS University Islamabad Lahore CampusLahore54000Pakistan syed Babar Ali school of science and Engineering Lahore University of Management SciencesLahore54000Pakistan Department of Computer science College of Computer and Information SciencesKing Saud UniversityRiyadh11633Saudi Arabia Department of Electrical Engineering Superior UniversityLahore54000Pakistan Department of Electrical Engineering Government College UniversityLahore54000Pakistan Department of Information and Communication Engineering Yeungnam UniversityGyeongsan38541Korea

An excessive use of non-linear devices in industry results in current harmonics that degrades the power quality with an unfavorable effect on power system *** this research,a novel control techniquebased Hybrid-Active Power-Filter(HAPF)is implemented for reactive power compensation and harmonic current component for balanced load by improving the Power-Factor(PF)and Total–Hormonic Distortion(THD)and the performance of a *** work proposed a soft-computing technique based on Particle swarm-Optimization(PsO)and Adaptive Fuzzy technique to avoid the phase delays caused by conventional control ***,the control algorithms are implemented for an instantaneous reactive and active current(Id-Iq)and power theory(Pq0)in *** prevent the degradation effect of disturbances on the system’s performance,Ps0-PI is applied in the inner loop which generate a required dc ***,a comparative analysis of both techniques has been presented to evaluate and validate the performance under balanced load *** presented result concludes that the Adaptive Fuzzy PI controller performs better due to the non-linearity and robustness of the ***,the gains taken from a tuning of the PsO based PI controller optimized with Fuzzy Logic Controller(FLC)are optimal that will detect reactive power and harmonics much faster and *** proposed hybrid technique minimizes distortion by selecting appropriate switching pulses for VsI(Voltage source Inverter),and thus the simulation has been taken in sIMULINK/*** proposed technique gives better tracking performance and robustness for reactive power compensation and harmonics *** a result of the comparison,it can be concluded that the PsO-basedAdaptive Fuzzy PI system produces accurate results with the lower THD and a power factor closer to unity than other techniques.

关键词： Harmonics compensation soft computing technique hybrid fuzzy PsO based PI controller HsAPF power quality

Quantum spin Hall and quantum valley Hall effects in trilayer graphene and their topological structures

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Chinese Physics B 2017年第12期26卷 481-490页

作者： Majeed Ur rehman A A Abid ICQD Hefei National Laboratory for Physical Sciences at Microscale Department of Physics University of Science and Technology of China Hefei 230026 China Key Laboratory of Geospace Environment(Chinese Academy of sciences) Department of Geophysics and Planetary Science University of Science and Technology of China Hefei 230026 China

The present study pertains to the trilayer graphene in the presence of spin orbit coupling to probe the quantum spin/valley Hall effect. The spin Chern-number Cs for energy-bands of trilayer graphene having the essence of intrinsic spin-orbit coupling is analytically calculated. We find that for each valley and spin, Cs is three times larger in trilayer graphene as compared to single layer graphene. since the spin Chern-number corresponds to the number of edge states, consequently the trilayer graphene has edge states, three times more in comparison to single layer graphene. We also study the trilayer graphene in the presence of both electric-field and intrinsic spin-orbit coupling and investigate that the trilayer graphene goes through a phase transition from a quantum spin Hall state to a quantum valley Hall state when the strength of the electric field exceeds the intrinsic spin coupling strength. The robustness of the associated topological bulk-state of the trilayer graphene is evaluated by adding various perturbations such as Rashba spin-orbit （RsO） interaction αR, and exchange-magnetization M. In addition, we consider a theoretical model, where only one of the outer layers in trilayer graphene has the essence of intrinsic spin-orbit coupling, while the other two layers have zero intrinsic spin-orbit coupling. Although the first Chern number is non-zero for individual valleys of trilayer graphene in this model, however, we find that the system cannot be regarded as a topological insulator because the system as a whole is not gaped.

关键词： trilayer graphene quantum spin Hall effect topological insulator quantum phase transition

stability of Quark star Models

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Communications in Theoretical Physics 2016年第5期65卷 575-584页

作者： M.Azam s.A.Mardan M.A.rehman Division of science and Technology University of Education Department of Mathematics University of the Management and Technology

In this paper,we investigate the stability of quark stars with four different types of inner matter configurations;isotropic,charged isotropic,anisotropic and charged anisotropic by using the concept of *** this purpose,we have applied local density perturbations technique to the hydrostatic equilibrium equation as well as on physical parameters involved in the *** conclude that quark stars become potentially unstable when inner matter configuration is changed and electromagnetic field is applied.

关键词： quark stars cracking density perturbations electromagnetic field

Facile synthesis and Crystal structures of New Ammonium sulfonates(CA-DNBs and TEA-TMBs)

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Chinese Journal of structural Chemistry 2013年第10期32卷 1465-1474页

作者： KHAN Islam Ullah ARsHAD muhammad Nadeem sAHIN Onur MUBAsHAR-Ur-rehman Hafiz MUNIR Ayesha HUMAYUN saba AsIRI Abdullah M Materials Chemistry Laboratory Department of Chemistry GC UniversityLahore 54000Pakistan Centre of Excellence for Advanced Materials Research(CEAMR) King Abdulaziz University P.O.Box 80203Jeddah 21589Saudi Arabia Chemistry Department Faculty of ScienceKing Abdulaziz University P.O.Box 80203Jeddah 21589Saudi Arabia scientific and Technological Research Application and Research Center Sinop University57010 SinopTurkey

The title compounds, C12HIoN307sCI （I） and C15H27NO3s （II）, crystallize in the monoclinic system, space group P21/c with a = 7.3995（1）, b = 27.8489（6）, c = 9.8246（2）/, fl = 131.349（1）, V = 1519.82（5） A3, Z = 4, F（000） = 768, Rint = 0.033 and s = 1.03 for I, and in the orthorhombic system, space group Pbca with a = 8.6227（1）, b = 16.1480（4）, c = 23.8774（6）/, V= 3324.67（12） A3, Z = 8, F（000） = 1312, Rint = 0.024 and s = 1.04 for II. We have devised a convenient procedure for the synthesis of fused organic salts resulting from 1：1 proton-transfer, using an amine and a derivative ofbenzenesulfonic acid. The synthesized salts have a number of applications ranging from their consumption as eco-friendly solvents and catalysts in organic syntheses, to being used as efficient precursors for the production of sulfa drugs. structures of compounds 3-chloroanilinium 2,4-dinitrobenzenesulfonate （CA-DNBs） and triethylaminium 2,4,6-trimethylbenzenesulfonate （TEA-TMBs） were determined by single-crystal X-ray diffraction studies and infrared spectroscopy.

关键词： crystal structure ammonium sulfonates 3-chloroanilinium2,4-dinitrobenzenesulfonate triethylaminium 2,4,6-trimethylbenzenesulfonate ionic liquids

Origin of Quartz Cement in the Paleogene sandstone Reservoir of shahejie Formation,Bohai Bay Basin,China

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Acta Geologica sinica(English Edition) 2022年第1期96卷 248-260页

作者： muhammad KAsHIF CAO Yingchang Nizam Ud DIN Uzair sIDDIQUE XI Kelai Faisal rehman Noor AHMED GU Xihao Mohammad saleh GAGHMAN Department of Earth sciences University of SargodhaSargodha 40100Pakistan school of Geosciences China University of PetroleumQingdaoShandong 266580China College of Earth sciences and Engineering Hohai UniversityNanjing 210098China Institute of Marine Geology and Resources Ocean CollegeZhejiang UniversityZhoushanZhejiang 316021China Department of Earth sciences Quaid-I-Azam UniversityIslamabad 45320Pakistan

The precipitation of authigenic quartz plays a significant role to reduce the reservoir characteristics and enhance the stiffness of the *** Es_(1) sandstone of shahejie Formation is acting as a significant hydrocarbon producing rock in the Nanpu *** methods like thin section petrography,cathodoluminescence(CL),scanning electron microscope(sEM,with EDs),and electron microprobe analysis has been used to reveal the origin of quartz cement as well as to evaluate the effect of quartz cement on reservoir *** studied sandstone is classified as immature to mature feldspathic litharenite and lithic arkose and consists of quartz,feldspar,rock fragments and *** studies and sEM analysis shows that the authigenic quartz is acting a significant cement that reduces the reservoir *** clay minerals(kaolinite and mixed layer illite to smectite)are dominant in the Es_(1) sandstone,that can reduce the reservoir ***,CL and thin section analysis reveal that there are two stages of quartz cement in the studied samples;that are pore filling authigenic cement and quartz overgrowth *** inclusion homogenization temperatures shows that stages of quartz cement were developed with continuous process from 70℃ to 130℃.Quartz cements were generally originated from I/s reaction,feldspar dissolution,conversion of rock fragments and pressure *** dissolution(K-feldspar)and kaolinite to illite reaction is an insignificant silica source for the silica cement which is internally precipitated in a close system with diffusion transporting ***,quartz cement significantly enhance the rock strengthen and brittleness effectively as well as it reduce the overall reservoir quality.

关键词： origin authigenic quartz silica sources diffusion shahejie Formation