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Conservation status evaluation of Berberis species across the Karakoram Mountain Ranges, Pakistan using IUCN Red List Categories and Criteria

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Journal of Forestry Research 2016年第6期27卷 1385-1390页

作者： Tika khan Imtiaz Ahmed khan Abdul Rehman Nisar Ahmed Integrated Mountain Area Research Centre Karakoram International University Department of Biological Sciences Karakoram International University Centre of Agriculture Biochemistry and Biotechnology University of Agriculture Faisalabad

Berberis species medicinal plants in Pakistan are endangered, high-value with important eco-cultural, commercial and livelihood roles in mountain communities. To assess the geographical distribution of Berberis species across the Karakoram Mountain Ranges in Pakistan, we used IUCN Red List Categories and Criteria （2001） to calculate the extent of occurrence （EOO, 〈100 km^2） and the area of occupancy （AOO, 〈10 km^2） of Berberis pseudumbellata subsp, pseudumbellata and B. pseudumbellata subsp. gilgitica. Overgrazing and habitat loss were key population- limiting factors. The two subspecies had contrasting responses to temperature, elevation, precipitation and insect susceptibility. B. pseudumbellata subsp, gilgitica is endemic to Gilgit-Baltistan and grows in single-cropping zone （ar- eas 〉 200 m a.s.1.）. Status evaluation revealed that both subspecies meet the criteria set for critically endangered species. Prolonged disregard of its declining population trend might lead to its extinction; therefore, integrated con- servation efforts are necessary.

关键词： Berberis Ecological zonation Critically endangered Extent of occurrence Karakoram Occupation area Spatial distribution

Electronic and thermoelectric properties of YbMg_(2)X_(2)(X=P,As,Sb,Bi)zintl compounds by first-principles method

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Journal of Rare Earths 2024年第1期42卷 147-154,I0006页

作者： Sajid khan Dil Faraz khan R.Neffati Tariq Usman Muhammad Waqar Ahsraf Shamim khan Saeed Ullah Jan G.Murtaza Department of Physics University of Science&Technology BannuBannu28100Pakistan Department of Physics Faculty of ScienceKing Khalid UniversityP.O.Box 9004AbhaSaudi Arabia Laboratoire de Physique de La Matiere Condensee Departement de PhysiqueFaculte des Sciences de TunisUniversite Tunis El ManarCampus Universitaire1060TunisTunisia Department of Physics Shaoxing UniversityShaoxing312000China Department of Mathematics&Natural Sciences Prince Mohammad Bin Fahd UniversityAlkhobar31952Saudi Arabia Materials Modeling Lab Department of PhysicsIslamia College Peshawar25120KhyberPakhtunkhwaPakistan

In this work the structural,electronic and thermoelectric properties of YbMg_(2)X_(2)(X=P,As,Sb,Bi)zintl compounds were investigated comprehensively using first principles *** electronic properties were studied using PBE GGA,TB-mBJ and hybrid(YS-PBE0)*** the structural parameters of optimized structures are in harmonious agreement to the available *** band structure study illustrates that the titled materials manifest metallic and semi metallic nature using PBE and TB-mBJ potentials while they show wide band gap semiconducting behavior by following hybrid(YS-PBE0)*** density of states(TDOS)and partial density of states(PDOS)were also calculated to glimpse the contribution of orbitals of atoms in the formation of *** properties were studied by using BoltzTraP2 code employed to *** get enormous values of Seebeck coefficient(S),power factor(PF)and thermoelectric figure of merit(ZT)for all the samples YbMg_(2)X_(2)(X=P,As,Sb,Bi),Moreover,the overwhelming transport properties for the titled compounds indicate the optimum level of carriers’concentration which pinpoints these materials to be better thermoelectrics in the 1-2-2 zintl family.

关键词： Zintl compounds Hybrid functional Band structure Thermoelectrics Rare earths

Pashto Characters Recognition Using Multi-Class Enabled Support Vector Machine

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Computers, Materials & Continua 2021年第6期67卷 2831-2844页

作者： Sulaiman khan Shah Nazir Habib Ullah khan Anwar Hussain Department of Computer Science University of SwabiSwabiPakistan Department of Accounting and Information Systems College of Business and EconomicsQatar UniversityDohaQatar

During the last two decades signicant work has been reported in the eld of cursive language’s recognition especially,in the Arabic,the Urdu and the Persian *** unavailability of such work in the Pashto language is because of:the absence of a standard database and of signicant research work that ultimately acts as a big barrier for the research *** slight change in the Pashto characters’shape is an additional challenge for *** paper presents an efcient OCR system for the handwritten Pashto characters based on multi-class enabled support vector machine using manifold feature extraction *** feature extraction techniques include,tools such as zoning feature extractor,discrete cosine transform,discrete wavelet transform,and Gabor lters and histogram of oriented gradients.A hybrid feature map is developed by combining the manifold feature *** research work is performed by developing a medium-sized dataset of handwritten Pashto characters that encapsulate 200 handwritten samples for each 44 characters in the Pashto *** results are generated for the proposed model based on a manifold and hybrid feature *** overall accuracy rates of 63.30%,65.13%,68.55%,68.28%,67.02%and 83%are generated based on a zoning technique,HoGs,Gabor lter,DCT,DWT and hybrid feature maps *** of the proposed model is also tested by comparing its results with a convolution neural network *** convolution neural network-based model generated an accuracy rate of 81.02%smaller than the multi-class support vector *** highest accuracy rate of 83%for the multi-class SVM model based on a hybrid feature map reects the applicability of the proposed model.

关键词： Pashto multi-class support vector machine handwritten characters database zoning and histogram of oriented gradients

Decoherence Effects on Multiplayer Cooperative Quantum Games

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Communications in Theoretical Physics 2011年第8期56卷 228-234页

作者： Salman khan M.Ramzan M.Khalid.khan Department of Physics Quaid-i-Azam University

We study the behavior of cooperative multiplayer quantum games [Q. Chen, Y. Wang, J.T. Liu, and K.L. Wang, Phys. Lett. A 327 （2004） 98; A.P. Flitney and L.C.L. Hollenberg, Quantum Inf. Comput. 7 （2007） 111] in the presence of decoherence using different quantum channels such as amplitude damping, depolarizing and phase damping. It is seen that the outcomes of the games for the two damping channels with maximum values of decoherence reduce to same value. However, in comparison to phase damping channel, the payoffs of cooperators are strongly damped under the influence amplitude damping channel for the lower values of decoherence parameter. In the case of depolarizing channel, the game is a no-payoff game irrespective of the degree of entanglement in the initial state for the larger values of decoherence parameter. The deeoherenee gets the cooperators worse off.

关键词： multiplayer cooperative quantum games payoffs Nash equilibria

Second Law Analysis and Optimization of Elliptical Pin Fin Heat Sinks Using Firefly Algorithm

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Computers, Materials & Continua 2020年第11期65卷 1015-1032页

作者： Nawaf N.Hamadneh Waqar A.khan Ilyas khan Department of Basic Sciences College of Science and Theoretical StudiesSaudi Electronic UniversityRiyadh11673Saudi Arabia Department of Mechanical Engineering College of EngineeringPrince Mohammad Bin Fahd UniversityAl Khobar31952Saudi Arabia Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh City72915Vietnam

One of the most significant considerations in the design of a heat sink is thermal management due to increasing thermal flux and miniature in *** heat sinks utilize plate or pin fins depending upon the required heat dissipation *** are designed to optimize overall *** pin fin heat sinks enhance heat transfer rates and reduce the pumping *** this study,the Firefly Algorithm is implemented to optimize heat sinks with elliptical *** pin-fins are arranged in an inline *** nature-inspired metaheuristic algorithm performs powerfully and efficiently in solving numerical global optimization *** on mass,energy,and entropy balance,three models are developed for thermal resistance,hydraulic resistance,and entropy generation rate in the heat *** major axis is used as the characteristic length,and the maximum velocity is used as the reference *** entropy generation rate comprises the combined effect of thermal resistance and pressure *** total EGR is minimized by utilizing the firefly *** optimization model utilizes analytical/empirical correlations for the heat transfer coefficients and friction *** is shown that both thermal resistance and pressure drop can be simultaneously optimized using this *** is demonstrated that the performance of FFA is much better than PPA.

关键词： Firefly algorithm mathematical models entropy generation rate elliptical pin-fin heat sinks thermal resistance pressure drop

MWCNTs/SWCNTs Nanofluid Thin Film Flow over a Nonlinear Extending Disc: OHAM Solution

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Journal of Thermal Science 2019年第1期28卷 115-122页

作者： GOHAR TAZA Gul WARIS khan MUHAMMAD Shuaib MUHAMMAD Altaf khan EBENEZER Bonyah Department of Mathematics University of Peshawar Department of Mathematics City University of Science and Information Technology Higher Education Department Khyber Pukhtunkhwa Department of Mathematics Islamia College Department of Mathematics Kumasi Techniical University

The aim of this research is the improvement towards the consumption of energy in the field of engineering and industry. The efforts have been paid to the enhancement of heat transmission and cooling process through a nanofluid coating of a nonlinear stretching disc. The combination of Water(H2 O) and multiple walled carbon nanotubes(MWCNT)/single walled carbon nanotubes(SWCNT) have been used as a nanofluid. The spreading of a thin nano-layer with variable thickness over a nonlinear and radially stretching surface has been considered. The estimated results of the problem have been accomplished using the Optimal Homotopy Analysis Method(OHAM). The residual errors of the OHAM method have been shown physically and numerically. The important physical parameters of skin friction and Nusselt number have been calculated and discussed. The other embedding parameters like generalized magnetic parameter, Prantl number, nanofluid volume fraction and Eckert number have been intended and discussed. The obtained results have been compared with the Numerical(ND-Solve) method for both sorts of CNTs. The closed agreement of both methods has been achieved.

关键词： CNTs-H2O based nanofluid variable thin layer nonlinear radially stretching disc magnetic field skin friction and Nusselt number OHAM & numerical method

Numerical solution of the Saint-Venant equations by an efficient hybrid finite-volume/finite-difference method

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Journal of Hydrodynamics 2018年第2期30卷 189-202页

作者： Wencong Lai Abdul A.khan Glenn Department of Civil Engineering Clemson University

A computationally efficient hybrid finite-volume/finite-difference method is proposed for the numerical solution of SaintVenant equations in one-dimensional open channel flows. The method adopts a mass-conservative finite volume discretization for the continuity equation and a semi-implicit finite difference discretization for the dynamic-wave momentum equation. The spatial discretization of the convective flux term in the momentum equation employs an upwind scheme and the water-surface gradient term is discretized using three different schemes. The performance of the numerical method is investigated in terms of efficiency and accuracy using various examples, including steady flow over a bump, dam-break flow over wet and dry downstream channels, wetting and drying in a parabolic bowl, and dam-break floods in laboratory physical models. Numerical solutions from the hybrid method are compared with solutions from a finite volume method along with analytic solutions or experimental measurements. Comparisons demonstrates that the hybrid method is efficient, accurate, and robust in modeling various flow scenarios, including subcritical, supercritical, and transcritical flows. In this method, the QUICK scheme for the surface slope discretization is more accurate and less diffusive than the center difference and the weighted average schemes.

关键词： Hybrid numerical method Saint-Venant equations shallow water flow

A New Idea of Fractal-Fractional Derivative with Power Law Kernel for Free Convection Heat Transfer in a Channel Flow between Two Static Upright Parallel Plates

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Computers, Materials & Continua 2020年第11期65卷 1237-1251页

作者： Dolat khan Gohar Ali Arshad khan Ilyas khan Yu-Ming Chu Kottakkaran Sooppy Nisar Department of Mathematics City University of Science and Information TechnologyPeshawar25000Pakistan Institute of Computer Sciences and Information Technology The University of AgriculturePeshawarPakistan Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh72915Vietnam Department of Mathematics Huzhou UniversityHuzhou313000China Hunan Provincial Key Laboratory of Mathematical Modeling and Analysis in Engineering Changsha University of Science&TechnologyChangsha410114China Department of Mathematics College of Arts and SciencesPrince Sattam bin Abdulaziz UniversityWadi Aldawaser11991Saudi Arabia

Nowadays some new ideas of fractional derivatives have been used successfully in the present research community to study different types of mathematical *** them,the significant models of fluids and heat or mass transfer are on *** recently a new idea of fractal-fractional derivative is introduced;however,it is not used for heat transfer in channel *** this article,we have studied this new idea of fractal fractional operators with power-law kernel for heat transfer in a fluid flow *** exactly,we have considered the free convection heat transfer for a Newtonian *** flow is bounded between two parallel static *** of the plates is heated *** proposed problem is modeled with a fractal fractional derivative operator with a power-law kernel and solved via the Laplace transform method to find out the exact *** results are graphically analyzed via MathCad-15 software to study the behavior of fractal parameters and fractional *** the influence of temperature and velocity profile,it is observed that the fractional parameter raised the velocity and temperature as compared to the fractal ***,a combined approach of fractal fractional explains the memory of the function better than fractional only.

关键词： Fractal-fractional derivative power law kernel convection heat transfer upright parallel plates

An Implementation of Haar Wavelet Based Method for Numerical Treatment of Time-fractional Schrdinger and Coupled Schrdinger Systems

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IEEE/CAA Journal of Automatica Sinica 2019年第1期6卷 177-187页

作者： Najeeb Alam khan Tooba Hameed the Department of Mathematics University of Karachi

The objective of this paper is to solve the timefractional Schr¨odinger and coupled Schr¨odinger differential equations(TFSE) with appropriate initial conditions by using the Haar wavelet approximation. For the most part, this endeavor is made to enlarge the pertinence of the Haar wavelet method to solve a coupled system of time-fractional partial differential equations. As a general rule, piecewise constant approximation of a function at different resolutions is presentational characteristic of Haar wavelet method through which it converts the differential equation into the Sylvester equation that can be further simplified easily. Study of the TFSE is theoretical and experimental research and it also helps in the development of automation science,physics, and engineering as well. Illustratively, several test problems are discussed to draw an effective conclusion, supported by the graphical and tabulated results of included examples, to reveal the proficiency and adaptability of the method.

关键词： Fractional calculus Haar wavelets operational matrix wavelets