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Propagation of Ion solitary Pulses in Dense Astrophysical Electron-Positron-Ion Magnetoplasmas

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Plasma science and Technology 2015年第12期17卷 1000-1005页

作者： ATA-UR-RAHMAN s.a.khan A.QAMAR Department of Physics Theoretical Plasma Physics GroupIslamia College Peshawar(A Public Sector University) National Centre for Physics QAU Campus Department of Physics University of Peshawar

In this paper,we theoretically investigate the existence and propagation of low amplitude nonlinear ion waves in a dense plasma under the influence of a strong magnetic *** plasma consists of ultra-relativistic and degenerate electrons and positrons and non-degenerate cold ***,the appearance of two distinct linear modes and their evolution is studied by deriving a dispersion equation with the aid of Fourier ***,the dynamics of low amplitude ion solitary structures is investigated via a Korteweg-de Vries equation derived by employing a reductive perturbation *** effects of various plasma parameters like positron concentration,strength of magnetic field,obliqueness of field,etc.,are discussed in *** the end,analytical results are supplemented through numerical analysis by using typical representative parameters consistent with degenerate and ultra-relativistic magnetoplasmas of astrophysical regimes.

关键词： degenerate relativistic perturbation solitary representative Electron appearance dense collective normalized

shocks and solitons in Ultradense Degenerate Electron-Positron-Ion Plasmas

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Communications in Theoretical Physics 2011年第1期55卷 151-157页

作者： s.a.khan Arshad M.Mirza National Centre for Physics Quaid-i-Azam University Campusand Department of PhysicsCOMSATS Institute of Information Technology Theoretical Plasma Physics Group Department of PhysicsQuaid-i-Azam University

The formation and propagation of shocks and solitons are investigated in an unmagnetized, ultradense plasma containing degenerate Fermi gas of electrons and positrons, and classical ion gas by employing Thomas-Fermi model. For this purpose, a deformed Korteweg-de Vries-Berger （dKdVB） equation is derived using the reductive perturbative technique for cold, adiabatic, and isothermal ions. Localized analytical solutions of dKdVB equation in planar geometry are obtained for dispersion as well as dissipation dominant cases. For nonplanar （cylindrical and spherical） geometry, time varying numerical shock wave solution of dKdVB equation is found. Its dispersion dominant case leading to the soliton solution is also discussed. The effect of ion temperature, positron concentration and dissipation is found significant on these nonlinear structures. The relevance of the results to the systems of scientific interest is pointed out.

关键词： degenerate plasma nonplanar geometry shocks solitons

Complementary effect of zoo compost with mineral nitrogen fertilisation increases wheat yield and nutrition in a low-nutrient soil

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Pedosphere 2022年第2期32卷 339-347页

作者： Muhammad s.a.khan Lynette K.ABBOTT Zakaria M.sOLAIMAN Peter R.MAWsON Ian s.WAITE sasha N.JENKINs school of Agriculture and Environment Institute of AgricultureThe University of Western AustraliaPerth WA 6009Australia Perth Zoo Department of BiodiversityConservation and AttractionsPerth WA 6151Australia Agricultural Officer(Headquarters) DirectorateSoil Fertility Research InstituteAgriculture DepartmentGovernment of the PunjabLahore 53700Pakistan

Excess nitrogen(N) fertiliser use in agriculture is associated with water pollution and greenhouse gas *** practices and programs to reduce N fertiliser application continue to be developed,inefficient fertiliser use *** that reduce mineral N fertiliser application are needed in a sustainable agricultural ecosystem to control leaching and gaseous losses for environmental *** study evaluated whether fully or partially replacing mineral N fertiliser with zoo compost(Perth Zoo) could be a good mitigation strategy to reduce mineral N fertiliser application without affecting wheat yield and *** achieve this,a glasshouse experiment was conducted to assess the complementary effect of zoo compost and mineral N fertiliser on wheat yield and nutrition in a sandy soil of southwestern ***,a chlorophyll meter was used to determine whether there was a correlation between chlorophyll content and soil mineral N content,grain N uptake,and grain protein content at the tillering(42 d after sowing(DAs)) and heading(63 DAs) growth *** standard practice for N application for this soil type in this area,100 kg ha^(-1),was used with a soil bulk density of 1.3 g cm^(-3) to calculate the amount of mineral N(urea,46% N) and Perth Zoo compost(ZC)(0.69% N) for each *** comprised a control(no nutrients added,T1),mineral N only(100 kg N ha^(-1),T2),ZC only(100 kg N ha^(-1),T7),and combinations of mineral N and ZC at different rates(mineral N at 100 kg N ha^(-1)+ ZC at 25 kg N ha^(-1)(T3),mineral N at 75 kg N ha^(-1)+ ZC at 25 kg N ha^(-1)(T4),mineral N at 75 kg N ha^(-1)+ ZC at 50 kg N ha^(-1)(T5),and mineral N at 50 kg N ha^(-1)+ ZC at 50 kg N ha^(-1)(T6)).The T6 treatment significantly increased grain yield(by 26%) relative to the T2 ***,the T7 treatment did not affect grain yield when compared to the T2 *** treatments with mineral N and ZC in combination significantly improved the

关键词： chlorophyll meter sPAD measurement integrated nutrient management nitrogen use efficiency reduced N fertiliser application wheat yield

Damped Kadomtsev–Petviashvili Equation for Weakly Dissipative solitons in Dense Relativistic Degenerate Plasmas

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Communications in Theoretical Physics 2017年第12期67卷 783-790页

作者： s.Ahmad Ata-ur-Rahman s.a.khan F.Hadi Department of Physics University of Kotli Azad Jammu and Kashmir Department of Physics Theoretical Plasma Physics Group Islami a College Peshawar (A Public Sector University) National Centre for Physics Quaid-i-Azam University Campus Department of Nuclear Engineering Kyoto University Department of Applied Physical and Material sciences University of Swat

We have investigated the properties of three-dimensional electrostatic ion solitary structures in highly dense collisional plasma composed of ultra-relativistically degenerate electrons and non-relativistic degenerate ions. In the limit of low ion-neutral collision rate, we have derived a damped Kadomtsev–Petviashvili(KP) equation using perturbation analysis. supplemented by vanishing boundary conditions, the time varying solution of damped KP equation leads to a weakly dissipative compressive soliton. The real frequency behavior and linear damping of solitary pulse due to ion-neutral collisions is discussed. In the presence of weak transverse perturbations, soliton evolution with damping parameter and plasma density is delineated pointing out the extent of propagation using typical parameters of dense plasma in the interior of white dwarfs.

关键词： dissipative solitons damped Kadomtsev–Petviashvili equation

巴基斯坦地方地震台网的检测能力和可靠性分析

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地震学报 2003年第1期25卷 55-61页

作者： M.Qaisar T.Mahmood s.a.khan 许忠淮原子能委员会微震研究项目组巴基斯坦伊斯兰堡45650

利用Bungum和Husebye的方法,分析了地方地震台网的检测能力和可靠性.用标准的计算机定位程序重新测定了地震位置.根据25年的地震记录,分别由震级-频度关系导出的50%、90%和100%的累积检测率估计了检测水平.对台网内地震,相应于100%检测... 详细信息

利用Bungum和Husebye的方法,分析了地方地震台网的检测能力和可靠性.用标准的计算机定位程序重新测定了地震位置.根据25年的地震记录,分别由震级-频度关系导出的50%、90%和100%的累积检测率估计了检测水平.对台网内地震,相应于100%检测率的震级下限为ML=1.7.用台网内固定的实际震源,研究了台网对震源位置的测定精度.对网内地震,震中测定误差小于4 km.最后讨论了台网连续工作时可能会遇到的影响检测能力的一些问题.

关键词：巴基斯坦地震台网检测能力可靠性分析地震记录震级频度

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一种提高C3+收率的工艺过程

石油石化节能与计量 1986年第4期 63-64页

作者： s.a.khan 王迂冬

DHX工艺流程能从溶解气、炼厂气和天然气中提高C3+收率几乎达100％。此过程已在加拿大埃索资源公司的朱地克里克工厂得到证实。将一套深冷膨胀装置进行了改造后,收率由72％增加到95％,在进气量衡定的操作情况下,收率达100％。它的改造... 详细信息

DHX工艺流程能从溶解气、炼厂气和天然气中提高C3+收率几乎达100％。此过程已在加拿大埃索资源公司的朱地克里克工厂得到证实。将一套深冷膨胀装置进行了改造后,收率由72％增加到95％,在进气量衡定的操作情况下,收率达100％。它的改造投资费少于75万美元,而额外得到的丙烷和较重的烃烷为800～1000桶/日。

关键词：脱乙烷塔乙烷进料烷烃 C3 液体甲烷烃类收率

Knowledge‐based deep learning system for classifying Alzheimer's disease for multi‐task learning

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CAAI Transactions on Intelligence Technology 2024年第4期9卷 805-820页

作者： Amol Dattatray Dhaygude Gaurav Kumar Ameta Ihtiram Raza khan Pavitar Parkash singh Renato R.Maaliw III Natrayan Lakshmaiya Mohammad shabaz Muhammad Attique khan Hany s.Hussein Hammam Alshazly Department of Data science University of WashingtonSeattleWashingtonUSA Department of Computer science&Engineering Parul Institute of TechnologyParul UniversityVadodaraGujaratIndia Department of Computer science Jamia HamdardDelhiIndia Department of Management Lovely Professional UniversityPhagwaraIndia 5 College of Engineering Southern Luzon State UniversityLucbanQuezonPhilippines Department of Mechanical Engineering Saveetha School of EngineeringSIMATSChennaiTamil NaduIndia Model Institute of Engineering and Technology JammuJ&KIndia Department of Computer science HITEC UniversityTaxilaPakistan Department of Computer science and Mathematics Lebanese American UniversityBeirutLebanon Electrical Engineering Department College of EngineeringKing Khalid UniversityAbhaSaudi Arabia Electrical Engineering Department Aswan UniversityAswanEgypt Faculty of Computers and Information South Valley UniversityQenaEgypt

Deep learning has recently become a viable approach for classifying Alzheimer's disease(AD)in medical ***,existing models struggle to efficiently extract features from medical images and may squander additional information resources for illness *** address these issues,a deep three‐dimensional convolutional neural network incorporating multi‐task learning and attention mechanisms is *** upgraded primary C3D network is utilised to create rougher low‐level feature *** introduces a new convolution block that focuses on the structural aspects of the magnetORCID:ic resonance imaging image and another block that extracts attention weights unique to certain pixel positions in the feature map and multiplies them with the feature map ***,several fully connected layers are used to achieve multi‐task learning,generating three outputs,including the primary classification *** other two outputs employ backpropagation during training to improve the primary classification *** findings show that the authors’proposed method outperforms current approaches for classifying AD,achieving enhanced classification accuracy and other in-dicators on the Alzheimer's disease Neuroimaging Initiative *** authors demonstrate promise for future disease classification studies.

关键词： classification deep learning

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苏门答腊-安达曼地震的GPs分析

世界地震译丛 2005年第1期36卷 9-12页

作者： s.a.khan O．Gudmundsson 左玉玲郑需要不详中国地震局地球物理研究所

2004年12月26日印度尼西亚苏门答腊地震是历史上破坏性最强的地震之一。此次地震的震级Mw=9．3(根据stein和Okal以简正模式振幅修订，http：//***／people／seth／research／***)，是自1900年以来记录到的第二最大地震。它发生在苏门答... 详细信息

2004年12月26日印度尼西亚苏门答腊地震是历史上破坏性最强的地震之一。此次地震的震级Mw=9．3(根据stein和Okal以简正模式振幅修订，http：//***／people／seth／research／***)，是自1900年以来记录到的第二最大地震。它发生在苏门答腊岛北部以西100千米的近海处，

关键词：苏门答腊—安达曼地震 GPs 震级板块运动断层带海啸全球定位系统

Effects of grain's shape-and size-polydispersities,orientation,and area fraction on tortuosity and permeability of 2D granular media

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Particuology 2024年第7期90卷 535-557页

作者： Ke Cao Huisu Chen Mohammad Iqbal khan Mingqi Li Lin Liu Jiangsu Key Laboratory of Construction Materials School of Materials Science and EngineeringSoutheast UniversityNanjing 211189China Department of Civil Engineering College of EngineeringKing Saud UniversityP.O.Box 800Riyadh 11421Saudi Arabia school of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China College of Civil and Transportation Engineering Hohai UniversityNanjing210098China

The microstructure of granular media, including grain's shape- and size-polydispersities, orientation, and area fraction can potentially affect its permeability. However, few studies consider the coupling effects of these features. This work employs geometrical probability and stereology to establish quantitative relationships between the above microstructural features and the geometric tortuosity of the two-dimensional granular media containing superellipse, superoval, and polygon grains. Then the lattice Boltzmann method (LBM) is used to determine the permeabilities of these granular media. By combining the tortuosity model and the LBM-derived permeabilities, modified K–C equations are formulated to predict the permeability and the shape factor, considering the grain's shape- and size-polydispersities, orientation, and area fraction. The reliability of these methods can be verified by comparing them with both our simulations and available experimental, theoretical, and numerical data reported in the literature. The findings implicate that the tortuosity and permeability of the granular media are strongly correlated with the grain's shape, orientation, and area fraction but unaffected by the size polydispersity and spatial arrangement of grains. Only circularity is not enough to derive a unified formula for considering the impact of grain shape on tortuosity and permeability, other shape parameters need to be explored in the future.

关键词： Geometric tortuosity Konzey-Carman equation shape and size ploydispersities Grain orientation Lattice Boltzmann method Granular media