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Structural elucidation of SARS-CoV-2 vital proteins: Computational methods reveal potential drug candidates against main protease, Nsp12 polymerase and Nsp13 helicase

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Journal of Pharmaceutical Analysis 2020年第4期10卷 320-328页

作者： Muhammad usman Mirza Matheus Froeyen Department of Pharmaceutical and Pharmacological Sciences Rega Institute for Medical ResearchMedicinal ChemistryUniversity of LeuvenB-3000LeuvenBelgium

Recently emerged SARS-CoV-2 caused a major outbreak of coronavirus disease 2019(COVID-19)and instigated a widespread fear,threatening global health *** date,no licensed antiviral drugs or vaccines are available against COVID-19 although several clinical trials are under way to test possible *** this urgent situation,computational drug discovery methods provide an alternative to tiresome high-throughput screening,particularly in the hit-to-lead-optimization *** of small molecules that specifically target viral replication apparatus has indicated the highest potential towards antiviral drug *** this work,we present potential compounds that specifically target SARS-CoV-2 vital proteins,including the main protease,Nsp12 RNA polymerase and Nsp13 *** integrative virtual screening and molecular dynamics simulations approach has facilitated the identification of potential binding modes and favourable molecular interaction profile of corresponding ***,the identification of structurally important binding site residues in conserved motifs located inside the active site highlights relative importance of ligand binding based on residual energy decomposition *** the current study lacks experimental validation,the structural information obtained from this computational study has paved way for the design of targeted inhibitors to combat COVID-19 outbreak.

关键词： SARS-CoV-2 COVID-19 outbreak CoV-Mpro CoV-Nsp12 polymerase CoV-Nsp13 helicase

Joint Non-Orthogonal Multiple Access (NOMA) & Walsh-Hadamard Transform: Enhancing the Receiver Performance

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China Communications 2018年第9期15卷 160-177页

作者： Muhammad Rehan usman Arsla Khan Muhammad Arslan usman Soo young Shin Department of Electrical Engineering The Superior College (University Campus) Department of IT Convergence Engineering Kumoh National Institute of Technology (KIT) Department of Electrical Engineering COMSATS University Islamabad Lahore Campus

Non-orthogonal multiple access(NOMA) is a new access method to achieve high performance gains in terms of capacity and throughput, so it is currently under consideration as one of the candidates for fifth generation(5 G) technologies. NOMA utilizes power domain in order to superimpose signals of multiple users in a single transmitted signal. This creates a lot of interference at the receive side. Although the use of successive interference cancellation(SIC) technique reduces the interference, but to further improve the receiver performance, in this paper, we have proposed a joint Walsh-Hadamard transform(WHT) and NOMA approach for achieving better performance gains than the conventional NOMA. WHT is a well-known code used in communication systems and is used as an orthogonal variable spreading factor(OVSF) in communication systems. Application of WHT to NOMA results in low bit error rate(BER) and high throughput performance for both low and high channel gain users. Further, it also reduces peak to average power ratio(PAPR) of the user signal. The results are discussed in terms of comparison between the conventionalNOMA and the proposed technique, which shows that it offers high performance gains in terms of low BER at different SNR levels, reduced PAPR, high user throughput performance and better spectral efficiency.

关键词： Bit error rate (BER) non-orthogonal multiple access (NOMA) orthogonal frequency division multiplexing (OFDM) peak to average power ratio (PAPR) successive interference cancellation (SIC) throughput and Walsh-Hadamard transform (WHT).

Defocus Blur Segmentation Using Local Binary Patterns with Adaptive Threshold

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Computers, Materials & Continua 2022年第4期71卷 1597-1611页

作者： usman Ali Muhammad Tariq Mahmood Future Convergence Engineering School of Computer Science and EngineeringKorea University of Technology and Education1600Chungjeol-roByeongcheon-myeonCheonan31253Korea

Enormousmethods have been proposed for the detection and segmentation of blur and non-blur regions of the *** to the limited available information about blur type,scenario and the level of blurriness,detection and segmentation is a challenging ***,the performance of the blur measure operator is an essential factor and needs improvement to attain *** this paper,we propose an effective blur measure based on local binary pattern(LBP)with adaptive threshold for blur *** sharpness metric developed based on LBP used a fixed threshold irrespective of the type and level of blur,that may not be suitable for images with variations in imaging conditions,blur amount and ***,the proposed measure uses an adaptive threshold for each input image based on the image and blur properties to generate improved sharpness *** adaptive threshold is computed based on the model learned through support vector machine(SVM).The performance of the proposed method is evaluated using two different datasets and is compared with five state-of-the-art *** analysis reveals that the proposed method performs significantly better qualitatively and quantitatively against all of the compared methods.

关键词： Adaptive threshold blur measure defocus blur segmentation local binary pattern support vector machine

Investigating the implications of technological innovations,financial inclusion,and renewable energy in diminishing ecological footprints levels in emerging economies

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Geoscience Frontiers 2023年第6期14卷 341-357页

作者： Najia Saqib Ilhan Ozturk Muhammad usman Department of Finance College of Business AdministrationPrince Sultan UniversityRiyadhSaudi Arabia College of Business Administration University of SharjahSharjahUAE Faculty of Economics Administrative and Social SciencesNisantasi UniversityIstanbulTurkey School of Economics and Management and Center for Industrial EconomicsWuhan UniversityWuhan430072China

The correlation between technological innovation,economic growth,renewable energy,and ecological footprint carries significant policy implications for environmental ***,financial inclusion can drastically affect the technology-climate nexus across different countries and its moderating impacts have received sufficient *** do this,this study examined how technological innovation,financial inclusion,economic growth,and renewable energy affected emerging economies’ecological footprint from 1990 to ***,this study also scrutinizes the moderating role of financial inclusion with other regressors on ecological *** account for structural shifts,disguised cointegration,and numerous breaks in panel regression,this study applies advanced panel estimation methods for empirical *** estimated outcomes exhibit that the influence of technical innovation,climate technologies,and renewable energy significantly reduces the ecological footprint ***,economic growth and financial inclusion significantly increase the ecological footprint levels in the emerging ***,the integration of innovative technology and renewable energy in emerging countries mitigates the adverse effects of financial inclusion by making it easier for creative technologies and reducing ecological *** results show that emerging countries’innovative technology and renewable energy sources should be integrated with financial inclusion to enable longterm mitigation of environmental damages and sustainable *** on these estimated findings,the research recommends that emerging economies should hasten technological innovations along with stronger financial development to curtail ecological concerns without hindering the pace of sustainable economic growth.

关键词： Environmental-related technology Financial inclusion Renewable energy Ecological footprints Emerging countries

Applications of synchrophasor technologies in power systems

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Journal of Modern Power Systems and Clean Energy 2019年第2期7卷 211-226页

作者： Muhammad Usama usman M. Omar FARUQUE Department of Electrical and Computer Engineering Center for Advanced Power Systems Florida State University

Synchrophasors are time-synchronized electrical measurements that represent both the magnitude and phase angle of the electrical sinusoids. Synchrophasors are measured by fast time-stamped devices called phasor measurement units(PMUs) to constitute the basis of realtime monitoring and control actions in the electric *** to its enhanced situational awareness capabilities,many applications of PMUs are presented in the literature in the past decades. This paper presents a comprehensive summary of synchrophasor technology, its architecture,optimal placement techniques and its applications in electric power transmission and distribution systems. These applications include wide-area situational awareness and monitoring, state estimation, fault location and protective relaying, islanding detection etc. This review also covers some of the existing challenges in its implementation and its potential applications.

关键词： Phasor measurement unit(PMU) Supervisory control and data acquisition(SCADA) Synchrophasor technology(ST) Power system

Dynamics of exact soliton solutions to the coupled nonlinear system using reliable analytical mathematical approaches

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Communications in Theoretical Physics 2021年第8期73卷 50-66页

作者： Muhammad Bilal usman Younas Jingli Ren Henan Academy of Big Data/School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China

Nonlinear Schrödinger-type equations are important models that have emerged from a wide variety of fields,such as fluids,nonlinear optics,the theory of deep-water waves,plasma physics,and so *** this work,we obtain different soliton solutions to coupled nonlinear Schrödinger-type(CNLST)equations by applying three integration tools known as the(G’/G^(2))-expansion function method,the modified direct algebraic method(MDAM),and the generalized Kudryashov *** soliton and other solutions obtained by these methods can be categorized as single(dark,singular),complex,and combined soliton solutions,as well as hyperbolic,plane wave,and trigonometric solutions with arbitrary *** spectrum of the solitons is enumerated along with their existence ***,2D,3D,and contour profiles of the reported results are also plotted by choosing suitable values of the parameters involved,which makes it easier for researchers to comprehend the physical phenomena of the governing *** solutions acquired demonstrate that the proposed techniques are efficient,valuable,and straightforward when constructing new solutions for various types of nonlinear partial differential equation that have important applications in applied sciences and *** the reported solutions are verified by substitution back into the original equation through the software package Mathematica.

关键词： soliton solutions exact solutions CNLST equations (G’/G^(2))-expansion function method MDAM generalized Kudryashov method

SI Engine Fueled with Gasoline, CNG and CNG-HHO Blend: Comparative Evaluation of Performance, Emission and Lubrication Oil Deterioration

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Journal of Thermal Science 2021年第4期30卷 1199-1211页

作者： usman Muhammad HAYAT Nasir BHUTTA Muhammad Mahmood Aslam Department of Mechanical Engineering University of Engineering and TechnologyLahore 54890Pakistan

Hydroxy gas (HHO) is one of the potential alternative fuels for spark ignition (SI) engine,notably due to simultaneous increase in engine performance and reduction in exhaust ***,impact of HHO gas on lubrication oil for longer periods of engine operation has not yet been *** study focuses on investigation of the effect of gasoline,CNG and CNG-HHO blend on lubrication oil deterioration along with engine performance and emissions in SI *** unit produces HHO gas at 4.72 L/min by using 6 g/L of KOH in the aqueous *** was supplied to the test engine at a pressure of 0.11 MPa using an electronically controlled solenoid *** tests were carried out at different speeds at 80%open throttle condition and various performance parameters such as brake power (BP),brake specific fuel consumption(BSFC),brake thermal efficiency (BTE),exhaust gas temperature and exhaust emissions (HC,CO_(2),CO and NO_(x))were *** addition,various lubrication oil samples were extracted over 120 h of engine running while topping for drain out volume and samples were analyzed as per ASTM ***-HHO blend exhibited better performance i.e.,15.4%increase in average BP in comparison to CNG,however,15.1%decrease was observed when compared to ***-HHO outperformed gasoline and CNG in the case of HC,CO_(2),CO and brake specific fuel consumption (31.1%decrease in comparison to gasoline).On the other hand,CNG-HHO produced higher average NO_(x) (12.9%) when compared to CNG ***,lubrication oil condition(kinematic viscosity,water contents,flash point and total base number (TBN)),wear debris (Iron (Fe),Aluminum(Al),Copper (Cu),Chromium (Cr)) and additives depletion (Zinc (Zn),Calcium (Ca)) presented a significant degradation in the case of CNG-HHO blend as compared to gasoline and *** oil analyses illustrated 19.6%,12.8%and 14.2%decrease in average viscosity,flash point and TBN for CNG-HHO blend ***,

关键词： spark ignition engine compressed natural gas hydrogen lubrication oil deterioration emission

FORCED OSCILLATIONS OF A CLASS OF NONLINEAR DISPERSIVE WAVE EQUATIONS AND THEIR STABILITY

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Journal of Systems Science & Complexity 2007年第2期20卷 284-292页

作者： Muhammad usman Bingyu ZHANG Department of Mathematical Sciences University of Cincinnati Cincinnati Ohio 45221-0025 USA

It has been observed in laboratory experiments that when nonlinear dispersive waves are forced periodically from one end of undisturbed stretch of the medium of propagation, the signal eventually becomes temporally periodic at each spatial point. The observation has been confirmed mathematically in the context of the damped Korteweg-de Vries （KdV） equation and the damped Benjamin-Bona-Mahony （BBM） equation. In this paper we intend to show the same results hold for the pure KdV equation （without the damping terms） posed on a finite domain. Consideration is given to the initial-boundary-value problem {ut＋ux＋uux＋uxxx=0, u（x,0）=φ（x）, 0〈x〈1, t〉0,u（0,t）=h（t）, u（1,t） = 0, ux（1,t） = 0, t〉*** is shown that if the boundary forcing h is periodic with small ampitude, then the small amplitude solution u of （＊） becomes eventually time-periodic. Viewing （＊）（without the initial condition） as an infinite-dimensional dynamical system in the Hilbert space L^2（0, 1）, we also demonstrate that for a given periodic boundary forcing with small amplitude, the system （＊） admits a （locally） unique limit cycle, or forced oscillation, which is locally exponentially stable. A list of open problems are included for the interested readers to conduct further investigations.

关键词： Forced oscillation stability the BBM equation the KdV equation time-periodic solution

Theoretical Investigation of Two-Dimensional Nonlinear Radiative Thermionics in Nano-MHD for Solar Insolation:A Semi-Empirical Approach

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Computer Modeling in Engineering & Sciences 2022年第2期130卷 751-776页

作者： usman Inayat Shaukat Iqbal Tareq Manzoor School of Systems and Technology University of Management and TechnologyLahore54000Pakistan Energy Research Centre COMSATS University IslamabadLahore CampusLahore54000Pakistan

In this contemporary study,theoritical investigation of nanofluidic model is ***-dimensional nanomaterials based mixed flow is considered *** solar radiative heat transport properties have been investigated over a nonlinearly stretched wall in the presence of magneto-hydrodynamic(MHD),by innovative application of semi analytical“optimal homotopy asymptotic method(OHAM)”.OHAM does not require any discretization,linearization and small parameter *** describes extremely precise 1^(st)/2^(nd) order solutions without the need of computing further higher order terms,therefore,fast convergence is *** governing model is transformed into system of ordinary differential equations(ODEs)by exploitation of similarity *** study the significance of radiation parameter alongwith thermophoresis parameter,a semi analytical solver is applied to the transformed *** this work,Brownianmotion,influence ofmagnetic field,Lewis number,Prandtl number,Eckert number and Biot number have investigated on velocity,temperature and nanoparticle concentration *** study provides sufficient number of graphical representations to demonstrate the inspiration of mentioned parameters.

关键词： Magneto-hydrodynamic(MHD) OHAM nanofluid solar radiative stretched wall