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Influence of rainfall infiltration on the stability of unsaturated coal gangue accumulated slope

Journal of Mountain Science 2021年第6期18卷 1696-1709页

作者： kaleem ullah jan khan WANG Chang-ming Muhammad Wasim jan khan LIANG Zhu LI Shuo LI Bai-long College of Construction Engineering Jilin UniversityChangchun 130021China Department of Management Sciences University College of Zhob(Sub-Campus BUITEMS)Balochistan 85200Pakistan

The slope instability is associated with increasing rate of rainfall infiltration which cause shear strength reduction and suction loss and the slope tend to failure. The influences of rainfall infiltration on the stability of clayey and sandy slopes have been analyzed but the effect of rainfall infiltration on the stability of unsaturated coal gangue accumulated slope was needed to study. Therefore, a coal gangue accumulated slope prone to failure in Fuxin area of Northeast China was considered to evaluate its failure mechanism under different rainfall events. The effects after five different rainfall events on slope stability were physically analyzed, numerically investigated and the results from both uncoupled(hydraulic) and coupled(hydromechanical) responses were compared using finite element analysis. It was observed that the decisive soaking and leaching under different rainfall conditions caused maximum deformation at the crest of slope due to maximum value of permeability coefficient of coal gangue. The critical duration of moderate intensity(147 mm/day) of rainfall for the instability of coal gangue accumulated slope is declared as five days. The results from finite element analysis in this paper further clarifies that increase in duration of rainfall infiltration process cause hysteretic change in positive pore-water pressure causing decrease in factor of safety and increase in deformation. It is concluded that the stability of unsaturated coal gangue accumulated slope is greatly influence by the coupled effect of stress and porewater pressure in comparison of uncoupled(hydraulic) analysis as the obtained factor of safety values after five days of rainfall infiltration were 0.9 and 1.1 respectively.

关键词： Hydro mechanical coupling Factor of safety Ground water table Rainfall infiltration Matric suction Coal gangue

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降雨入渗触发非饱和煤矸石堆积边坡失稳的机理研究

降雨入渗触发非饱和煤矸石堆积边坡失稳的机理研究

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作者： kaleem ullah jan khan 吉林大学

学位级别：硕士

土坡的稳定性与降雨渗透过程有关,其特点是剪切强度降低以及吸力损失,从而最终导致了失稳。土坡失稳主要发生在降雨期间或降雨后,虽然已经被证明为降雨渗透导致土体强度降低以及孔隙水压力迅速增加而造成,但引发斜坡失稳的重要影响机理... 详细信息

土坡的稳定性与降雨渗透过程有关,其特点是剪切强度降低以及吸力损失,从而最终导致了失稳。土坡失稳主要发生在降雨期间或降雨后,虽然已经被证明为降雨渗透导致土体强度降低以及孔隙水压力迅速增加而造成,但引发斜坡失稳的重要影响机理还没有得到充分的讨论。降雨强度和降雨持续时间对边坡稳定性的影响,但降雨渗透过程对煤矸石堆积边坡稳定性的影响尚需深入研究。为此研究降雨入渗过程对土坡稳定性的影响,尤其对世界范围内广泛分布的矿渣堆积体稳定性及环境安全具有重要意义。降雨特征(降雨强度和持续时间)和土体的导水性影响着边坡的稳定状态及失效类型。一般来说,土坡破坏的机理有两种,即降雨湿润锋的传播导致垫层吸力的丧失以及地下水位的上升。到目前为止,仍然没有明确的指标来确定导致矿渣型边坡失效的主导参数。因此,本研究在开展东北阜新地区一煤矸石堆积边坡失稳机制研究中考虑了降雨渗透过程。通过收集已有资料、现场调查、实验室试验和数值模拟方法,较深入研究了煤矸石堆积边坡降雨诱发的失稳过程及其机理。采用渗流-应力耦合和非耦合有限元分析方法,对煤矸石堆积边坡的失效机理进行评价。采用物理模型测试分析了不同降雨条件下土坡中孔隙水压力的分布特征,采用有限元法数值方法按照渗流-应力耦合和非耦合两张方式研究了不同降雨持续时间(1天、2天、3天、4天和5天)和降雨强度对边坡变形破坏的影响。通过在坡面不同位置(坡顶、坡中、坡尖)设置监测点,观察并比较每次降雨后孔隙水压力的变化、变形规律和稳定性。煤矸石的高渗透性与在坡趾附近观察到的因水流而产生的最大变形进一步解释了坡体向下运动的原因,与现场观测和物理模型的观测结果有较好的一致性。研究结果还表明,渗透率的增加导致孔隙水压力的滞后性增加,土坡稳定系数下降。耦合分析中的安全系数(应力和孔隙水压力的耦合效应)与未耦合分析(水力反应效应)相比显著降低。为防止边坡进一步破坏,防止其对道路交通的影响,采用锚固与水平排水相结合的设计。建议在边坡顶部采用混凝土梁锚杆加固路基,在坡脚附近设置桩排。引入水平排水系统,分流雨水,保护边坡和道路的顶部和底部。采用极限平衡Bishop法分析了桩锚加固的效果,评价了加固方案对边坡安全系数的影响。结果表明:桩锚加固土边坡的安全系数由0.9提高到1.14;利用工程价值研究,在滑坡区设计水平排水系统,控制滑坡体内过量降雨入渗,保护坡顶和坡底道路,分流雨水。

关键词：煤矸石堆积体降雨入渗过程水-力耦合分析非饱和土力学安全系数治理措施

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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

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中巴经济走廊是巴基斯坦的中国债务陷阱吗？

中巴经济走廊是巴基斯坦的中国债务陷阱吗？

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作者： kaleem ullah khan 山东财经大学

学位级别：硕士

中巴经济走廊(CPEC)是中国“一带一路”倡议(BRI)下的旗舰项目,引发了对其经济影响和对巴基斯坦债务可持续性潜在影响的广泛讨论。本研究对中巴经济走廊(CPEC)进行了全面分析,探讨了其多方面的维度,包括基础设施发展、能源项目、经济增... 详细信息

中巴经济走廊(CPEC)是中国“一带一路”倡议(BRI)下的旗舰项目,引发了对其经济影响和对巴基斯坦债务可持续性潜在影响的广泛讨论。本研究对中巴经济走廊(CPEC)进行了全面分析,探讨了其多方面的维度,包括基础设施发展、能源项目、经济增长潜力和地缘政治意义。通过对经验证据、金融机制??和项目成果的审查,该研究批判性地评估了中巴经济走廊(CPEC)作为巴基斯坦潜在“债务陷阱”的普遍说法,为该走廊对巴基斯坦经济的影响提供了细致入微的视角。调查结果显示,中巴经济走廊是巴基斯坦经济转型、加强能源安全、基础设施发展和区域互联互通的重要催化剂。中巴经济走廊(CPEC)下的战略投资具有促进长期经济增长、提高出口竞争力并吸引大量外国直接投资的潜力。然而,这些好处的实现取决于有效的债务管理、经济政策改革和资金来源的多元化。该研究强调了透明财务规划和实施全面改革的重要性,以确保中巴经济走廊的经济红利有助于可持续发展和债务可持续性。与简化的“债务陷阱”叙述相反,本研究认为,通过战略性金融管理和结构性改革,中巴经济走廊可以在增强巴基斯坦经济主权和促进可持续发展方面发挥关键作用。该研究的结论是,尽管面临挑战,中巴经济走廊仍为经济振兴和区域一体化提供了前所未有的机遇,标志着巴中关系进入了新时代,并为“一带一路”的更广泛目标做出了贡献。

关键词：中巴经济走廊(CPEC) 一带一路倡议(BRI) 债务可持续性

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General Solution for Unsteady Natural Convection Flow with Heat and Mass in the Presence of Wall Slip and Ramped Wall Temperature

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Communications in Theoretical Physics 2019年第6期71卷 647-657页

作者： Saeed ullah jan Sami Ul Haq Syed Inayat Ali Shah Ilyas khan Muhammad Atif khan Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh CityVietnam Department of Mathematics Islamia College UniversityPeshawar25000Pakistan Department of Mathematics Kohat University of Science&TechnologyKohat26000Pakistan

This work is focused on the effect of heat and mass transfer with unsteady natural convection flow of viscous fluid along with ramped wall temperature under the assumption of the slip wall condition at the boundary. Analytical solutions are obtained by using Laplace transformation to the non-dimensional set of governing equations containing velocity, temperature and concentration. Moreover, the expression for skin-friction is derived by differentiating the analytical solutions of fluid velocity. Numerical tables for Skin-friction, Sherwood number and Nusselt-number are examined. For the physical aspects of the flow, we use various values of involved physical parameters such as Prandtl number(Pr), slip parameter(η), Schmidt number(Sc), buoyancy ratio parameter(N), Sherwood number(Sh), and time(t). Additionally, the general solutions are plotted graphically and a comprehensive theoretical section of numerical discussions is included.

关键词： slip boundary condition heat and mass transfer skin-friction

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Disintegration of uncertainties associated with real-time multi-satellite precipitation products in diverse topographic and climatic area in Pakistan

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Journal of Mountain Science 2021年第3期18卷 716-734页

作者： Muhammad MASOOD Ghulam NABI Muhammad BABUR Aftab Hussain AZHAR Muhammad kaleem ullah Centre of Excellence in Water Resources Engineering University of Engineering&Technology GT-RoadLahore 54890Pakistan Civil Engineering Department University of Central PunjabLahore 54782Pakistan Directorate of Hydrology Pakistan Water&Power Development Authority(WAPDA)MDO-WAPDAMangla Dam10200Pakistan Civil Engineering Department University of LahoreLahore 54000Pakistan

Satellite-based Precipitation Estimates(SPEs)have gained importance due to enhanced spatial and temporal resolution,particularly in Indus basin,where raingauge network has fewer observation stations and drainage area is laying in many *** of SPEs is based on indirect mechanism,therefore,assessment and correction of associated uncertainties is *** the present study,disintegration of uncertainties associated with four prominent real time SPEs,IMERG,TMPA,CMORPH and PERSIANN has been conducted at grid level,regional scale,and summarized in terms of regions as well as whole study area *** bias has been disintegrated into hit,missed,false biases,and Root Mean Square Error(RMSE)into systematic and random errors.A comparison among gauge-and satellite-based precipitation estimates at annual scale,showed promising result,encouraging use of real time SPEs in the study *** grid basis,at daily scale,from box plots,the median values of total bias(-0.5 to 0.5 mm)of the used SPEs were also encouraging although some under/over estimations were noted in terms of hit bias(-0.15 to 0.05 mm/day).Relatively higher values of missed(0.3 to 0.5 mm/day)and false(0.5 to 0.7 mm/day)biases were *** detected average daily RMSE,systematic errors,and random errors were also comparatively ***-scale spatial distribution of uncertainties revealed lower values of uncertainties in plain areas,depicting the better performance of satellite-based products in these ***,in areas of high altitude(>4000 m),due to complex topography and climatic conditions(orographic precipitation and glaciated peaks)higher values of biases and errors were *** barriers and point scale gauge data could also be a cause of poor performance of SPEs in these areas,where precipitation is more on ridges and less in valleys where gauge stations are usually *** system’s size and intensity can also be a reason of higher biases,because M

关键词： Satellite precipitation Real-time Error characterization IMERG Indus Basin

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Feasibility-Guided Constraint-Handling Techniques for Engineering Optimization Problems

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Computers, Materials & Continua 2021年第6期67卷 2845-2862页

作者： Muhammad Asif jan Yasir Mahmood Hidayat ullah khan Wali khan Mashwani Muhammad Irfan Uddin Marwan Mahmoud Rashida Adeeb khanum Ikramullah Noor Mast Institute of Numerical Sciences Kohat University of Science&TechnologyKohatPakistan Department of Economics Abbottabad University of Science&TechnologyAbbottabadPakistan Institute of Computing Kohat University of Science&TechnologyKohatPakistan Faculty of Applied Studies King Abdulaziz UniversityJeddahSaudi Arabia Jinnah College for Women University of PeshawarPeshawarPakistan Department of Physics Kohat University of Science&TechnologyKohatPakistan

The particle swarm optimization(PSO)algorithm is an established nature-inspired population-based meta-heuristic that replicates the synchronizing movements of birds and *** is essentially an unconstrained algorithm and requires constraint handling techniques(CHTs)to solve constrained optimization problems(COPs).For this purpose,we integrate two CHTs,the superiority of feasibility(SF)and the violation constraint-handling(VCH),with a *** CHTs distinguish feasible solutions from infeasible ***,in SF,the selection of infeasible solutions is based on their degree of constraint violations,whereas in VCH,the number of constraint violations by an infeasible solution is of more ***,a PSO is adapted for constrained optimization,yielding two constrained variants,denoted SF-PSO and *** SF-PSO and VCH-PSO are evaluated with respect to ve engineering problems:the Himmelblau’s nonlinear optimization,the welded beam design,the spring design,the pressure vessel design,and the three-bar truss *** simulation results show that both algorithms are consistent in terms of their solutions to these problems,including their different available *** of the SF-PSO and the VCHPSO with other existing algorithms on the tested problems shows that the proposed algorithms have lower computational cost in terms of the number of function evaluations *** also report our disagreement with some unjust comparisons made by other researchers regarding the tested problems and their different variants.

关键词： Constrained evolutionary optimization constraint handling techniques superiority of feasibility violation constraint-handling technique swarm based evolutionary algorithms particle swarm optimization engineering optimization proble

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A Framework for Systematic Classification of Assets for Security Testing

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Computers, Materials & Continua 2021年第1期66卷 631-645页

作者： Sadeeq jan Omer Bin Tauqeer Fazal Qudus khan George Tsaramirsis Awais Ahmad Iftikhar Ahmad Imran Maqsood Niamat ullah National Center for Cyber Security Department of CS&ITUniversity of Engineering&TechnologyPeshawarPakistan Department of Information Technology FCITKing Abdulaziz UniversityJeddahSaudi Arabia Dipartimento di Informatica(DI) UniversitàDegli Studi di Milano StataleVia Celoria 18MilanoItaly Department of Computer Science&IT University of Engineering&TechnologyPeshawarPakistan Department of Software Engineering University of Engineering&TechnologyMardanPakistan University of Buner BunerPakistan

Over the last decade,a significant increase has been observed in the use of web-based Information systems that process sensitive information,e.g.,personal,financial,*** this increased use,the security of such systems became a crucial aspect to ensure safety,integrity and authenticity of the *** achieve the objectives of data safety,security testing is ***,with growth and diversity of information systems,it is challenging to apply security testing for each and every ***,it is important to classify the assets based on their required level of security using an appropriate *** this paper,we propose an asset security classification technique to classify the System Under Test(SUT)based on various factors such as system exposure,data criticality and security *** perform an extensive evaluation of our technique on a sample of 451 information ***,we use security testing on a sample extracted from the resulting prioritized systems to investigate the presence of *** technique achieved promising results of successfully assigning security levels to various assets in the tested environments and also found several vulnerabilities in them.

关键词： Security security testing privacy asset classification

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RBF-FD Method for Some Dispersive Wave Equations and Their Eventual Periodicity

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Computer Modeling in Engineering & Sciences 2020年第5期123卷 797-819页

作者： Marjan Uddin Hameed ullah jan Muhammad Usman Department of Basics Sciences UETPeshawarPakistan Department of Mathematics University of DaytonDaytonUSA

In this paper,we approximate the solution and also discuss the periodic behavior termed as eventual periodicity of solutions of(IBVPs)for some dispersive wave equations on a bounded domain corresponding to periodic *** constructed numerical scheme is based on radial kernels and local in nature like finite difference *** temporal variable is executed through RK4 *** to the local nature and sparse differentiation matrices our numerical scheme efficiently recovers the *** results achieved are validated and examined with other methods accessible in the literature.

关键词： RBFs meshless methods RBF-FD scheme eventual periodicity BBM and KdV type equations.

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Molecular and in vitro biochemical assessment of chemosensory protein 10 from brown planthopper Nilaparvata lugens at acidic pH

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Journal of Integrative Agriculture 2022年第3期21卷 781-796页

作者： Muhammad Irfan WARIS Aneela YOUNAS Rana Muhammad kaleem ullah Fatima RASOOL Muhammad Muzammal ADEEL WANG Man-qun College of Plant Science and Technology Huazhong Agricultural UniversityWuhan 430070P.R.China National Center for Bioinformatics Quaid-i-Azam UniversityIslamaba 45320Pakistan College of Informatics Huazhong Agricultural UniversityWuhan 430070P.R.China

Chemosensory proteins(CSPs)are important molecular components of the insect olfactory system,which are involved in capturing,binding,and transporting hydrophobic odour molecules across the sensillum in sensillar lymph in regulating insect *** protein family(CSPs)is also involved in many other systems that are not linked to olfactory receptors in olfactory *** brown planthopper(BPH)is a monophagous pest of rice that causes damage by sucking phloem sap and transmitting a number of diseases caused by *** this study,fluorescence competitive binding assay and fluorescence quenching assay at acidic p H were performed as well as homology modelling to describe the binding affinity of Nlug *** competitive binding assay(FCBA)demonstrated that Nlug CSP10 bound strongly to nonadecane,farnesene,and 2-tridecanone at acidic p *** results of FCBA indicated that Nlug CSP10 bound different ligands at the physiological p H(5.0)of the bulk sensillum *** quenching assay demonstrated that Nlug CSP10 generated a stable complex with 2-tridecanone,while two ligands nonadecane and farnesene collided due to molecular *** interaction of selected ligands with the modelled structure of Nlug CSP10 was also analyzed,which found the key amino acids(Gln23,Gln24,Gln25,Asn27,Met33,Ser34,Ile35,Tyr36,Asn42,Met43,Val45,Asn46,Asn93,Arg96,Ala97,Lys99,and Ala100)in Nlug CSP10 that were involved in binding of volatile *** present study contributes to the binding profile of Nlug CSP10 that promotes the development of behaviorally active ligands based on BPH olfactory system.

关键词： insect olfaction chemosensory protein Nilaparvata lugens fluorescence competitive binding assay fluorescence quenching assay molecular docking

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