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Heterogeneous Expansion of End-moraine Dammed Lakes in the Hindukush-Karakoram-Himalaya Ranges of Pakistan during 2001-2013

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Journal of Mountain Science 2015年第5期12卷 1113-1124页

作者： Arshad ASHRAF Rozina NAZ Muhammad Bilal iqbal Climate Change Alternate Energy and Water Resources Institute (CAEWRI) National Agricultural Research Center

Global climate change during the twentieth century had a significant impact on the glaciers that resulted in creation of new lakes and expansion of existing ones, and ultimately an increase in the number of glacial lake outburst floods(GLOFs) in the Himalayan region. This study reports variation of the end-moraine dammed lakes in the high altitude Hindukush-Karakoram-Himalaya(HKH) region of Pakistan to evaluate future floods hazard under changing climate in this region. An integrated temporal remote sensing and Geographic information system(GIS) based approach using satellite images of Landsat-7 and 8 was adopted to detect 482 endmoraine dammed lakes out of which 339 lakes(>0.02 km2) were selected for temporal change analysis during the 2001-2013 period. The findings of the study revealed a net expansion in the end-moraine dammed lakes area in the Karakoram(about 7.7%) and in the Himalayas(4.6%), while there was a net shrinkage of about 1.5% in the lakes area in the Hindukush range during this period. The percentage increase in the lakes' area was highest above 4500 m asl in the Hindukush, within 3500-4000 m asl in the Himalayas and below 3500 m asl in the Karakoram range. The overall positive change in the lakes' area appears to prevail in various altitudinal ranges of the region. The heterogeneous areal changes in the endmoraine dammed lakes might be attributed to different climate regimes and glacial hydrodynamics in the three HKH ranges. A periodic monitoring of the glacial lakes and their associated glaciers is essential for developing effective hazard assessment and risk reduction strategies for this high altitude Himalayan region.

关键词： End-moraine glacial lakes GLOF Karakoram Himalayan region

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ON A COUPLED INTEGRO-DIFFERENTIAL SYSTEM INVOLVING MIXED FRACTIONAL DERIVATIVES AND INTEGRALS OF DIFFERENT ORDERS

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Acta Mathematica Scientia 2021年第4期41卷 1366-1384页

作者： bashir AHMAD Ravi P.AGARWAL Abrar BROOM Ahmed ALSAEDI Nonlinear Analysis and Applied Mathematics(NAAM)-Research Group Department of MathematicsFaculty of ScienceKing Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia Department of Mathematics Texas A&M UniversityKingsvilleTexas 78363-8202USA

By applying the standard fixed point theorems,we prove the existence and uniqueness results for a system of coupled differential equations involving both left Caputo and right Riemann-Liouville fractional derivatives and mixed fractional integrals,supplemented with nonlocal coupled fractional integral boundary *** example is also constructed for the illustration of the obtained results.

关键词： Fractional differential equations Caputo and Riemann-Liouville fractional derivatives systems existence fixed point theorems

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Influence of accelerated curing on the compressive strength of polymer-modified concrete

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Frontiers of Structural and Civil Engineering 2022年第5期16卷 589-599页

作者： Izhar AHMAD Kashif Ali KHAN Tahir AHMAD Muhammad ALAM Muhammad Tariq bashir College of Civil and Transportation Engineering Hohai UniversityNanjing 210098China Department of Civil Engineering Muslim Youth UniversityIslamabad 44000Pakistan Department of Civil Engineering CECOS University of IT&Emerging SciencesPeshawar 25000Pakistan Department of Civil Engineering University of Engineering&TechnologyMardan 23200Pakistan

In recent building practice,rapid construction is one of the principal ***,in designing concrete structures,compressive strength is the most significant of all *** 3-d and 7-d compressive strength reflects the strengths at early phases,the ultimate strength is *** effort has been made in this study to develop mathematical models for predicting compressive strength of concrete incorporating ethylene vinyl acetate(EVA)at the later ***-Smirnov(KS)goodness-of-fit test was used to examine distribution of the *** compressive strength of EVA-modified concrete was studied by incorporating various concentrations of EVA as an admixture and by testing at ages of 28,56,90,120,210,and 365 *** accelerated compressive strength at 3.5 hours was considered as a reference strength on the basis of which all the specified strengths were predicted by means of linear regression *** on the results of KS goodness-of-fit test,it was concluded that KS test statistics value(D)in each case was lower than the critical value 0.521 for a significance level of 0.05,which demonstrated that the data was normally *** on the results of compressive strength test,it was concluded that the strength of EVA-modified specimens increased at all ages and the optimum dosage of EVA was achieved at 16%***,it was concluded that predicted compressive strength values lies within a 6%difference from the actual strength values for all the mixes,which indicates the practicability of the regression *** research work may help in understanding the role of EVA as a viable material in polymer-based cement composites.

关键词： compressive strength prediction polymer-modified concrete linear regression fit early age strength ethylene vinyl acetate

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CNTFET Based Fully Differential First Order All Pass Filter

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Computer Systems Science & Engineering 2023年第3期44卷 2425-2438页

作者： Muhammad I.Masud iqbal A.Khan Department of Electrical Engineering Umm Al Qura UniversityMakkah21955Saudi Arabia

A novel,carbon nanotubefield effect transistor(CNTFET)based fully differentialfirst order all passfilter(FDFAPF)circuit configuration is *** FDFAPF uses CNTFET based negative transconductors(NTs)and positive transconductors(PTs)in its *** proposed circuit topology employs two PTs,two NTs,two resistors and one *** the passive components of the realized topology are *** only fully differentialfirst order all passfilter(AO-FDFAPF)topology is also derived from the proposed *** electronic tunability of the AO-FDFAPF is obtained by controlling the employed CNTFET based varactor.A tunabilty of pole frequency in the range of 10.5 to 26 GHz is *** the circuits are potential candidates for high frequency fully differential analog signal processing *** compared to prior state-of-the-art works,both the realized topologies have achieved highest pole frequency and lowest power ***,they utilize compact circuit structures and suitable for low voltage ***,both topologies work equally well in the deep *** proposedfilters are analyzed and verified through HPSPICE simulations by utilizing Stanford CNTFET model at 16 nm technology *** is observed that the proposed circuit simulation outcomes verify the theory.

关键词： Fully differential CNTFET all passfilters pole frequency tunability

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On the Lüders band formation and propagation in NiTi shape memory alloys

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Journal of Materials Science & Technology 2022年第21期116卷 22-29页

作者： bashir S.Shariat Yingchao Li Hong Yang Yunzhi Wang Yinong Liu Department of Mechanical Engineering The University of Western Australia35 Stirling HighwayPerthWA 6009Australia Department of Materials Science and Engineering The Ohio State UniversityColumbusOH 43210USA

Near-equiatomic NiTi shape memory alloys are known to exhibit Lüders-type deformation associated with a stress-induced *** studies have been conducted in the past mainly focusing on the macroscopic characteristics of the phenomenon and some theories have been proposed in the literature to explain its mechanisms,but some aspects of this phenomenon are still unclear,particularly at the microscopic *** study investigated the local strain evolution during the initiation and propagation of Lüders band in a pseudoelastic NiTi alloy during tensile deformation by means of digital image correlation(DIC)*** on the evidence collected,distinct stages of Lüders band formation and propagation are defined and the corresponding local strain rates are *** local strain rates are much higher than the global strain rate of the testing,giving insight to the mechanism of this phenomenon.

关键词： Shape memory alloy(SMA) NiTi Martensitic transformation Lüders-type deformation Lüders band Digital image correlation(DIC)

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Impact of Land-Use Practices on Sediment Yield in the Dhrabi Watershed of Pakistan

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Journal of Environmental Science and Engineering(A) 2012年第3期1卷 406-420页

作者： Muhammad Nadeem iqbal Theib Y. Oweis Muhammad Ashraf bashir Hussain Abdul Soil and Water Conservation Research Institute （SA WCRI） Chakwa148800 Pakistan International Center for Agricultural Research in the Dry Areas （ICARDA） National Agricultural Research Centre Islamabad44000 Pakistan International Center for Agricultural Research in the Dry Areas （ICARDA） Aleppo 15310 Syria

Soil erosion by water is one of the most important land degradation processes in the sloping rainfed lands in Pakistan. A study was conducted in the Dhrabi watershed of Pakistan to evaluate sediment yield associated with rainfall-runoff under various land-use practices. Five sub-catchments with sizes varying from 1.5 to 350 ha were selected for measurement of rainfall, runoff and sediment yield. Soil conservation techniques were also introduced to reduce the soil erosion. All runoff events occurred in the summer especially during monsoon season （July-September）. Sediment yield of two small gully catchments ranged from 4.79 to 8.34 t/ha/yr in 2009, a relatively dry year. In 2010, the annual sediment yield was 8.15 to 12.31 t/ha. Terraced catchment with arable crops produced annual 4.1 t/ha of sediment as compared to 12.31 t/ha by the adjacent gully catchment showing high potential of terraces in reducing erosion. Runoff coefficients calculated for these catchments vary from 0.09 to 0.75. The macro and micro nutrients present in the sediment indicate that these nutrients are being depleted due to soil erosion.

关键词： Soil erosion sediment yield rainfall runoff vegetative cover soil conservation structures.

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Stochastic maximum power point tracking of photovoltaic energy system under partial shading conditions

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Protection and Control of Modern Power Systems 2021年第1期6卷 383-395页

作者： Bushra iqbal Ali Nasir Ali Faisal Murtaza Department of Electrical Engineering University of Central PunjabLahorePakistan

A large portion of the available power generation of a photovoltaic (PV) array could be wasted due to partial shading, temperature and irradiance effects, which create current/voltage imbalance between the PV modules. Partial shading is a phenomenon which occurs when some modules in a PV array receive non-uniform irradiation due to dust, cloudy weather or shadows of nearby objects such as buildings, trees, mountains, birds etc. Maximum power point tracking (MPPT) techniques are designed in order to deal with this problem. In this research, a Markov Decision Process (MDP) based MPPT technique is proposed. MDP consists of a set of states, a set of actions in each state, state transition probabilities, reward function, and the discount factor. The PV system in terms of the MDP framework is modelled first and once the states, actions, transition probabilities, and reward function, and the discount factor are defined, the resulting MDP is solved for the optimal policy using stochastic dynamic programming. The behavior of the resulting optimal policy is analyzed and characterized, and the results are compared to existing MPPT control methods.

关键词： Maximum power point tracking Markov decision process Photovoltaic energy systems Partial shading

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Elastic Deformation Analysis on MHD Viscous Dissipative Flow of Viscoelastic Fluid:An Exact Approach

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Communications in Theoretical Physics 2017年第5期67卷 561-568页

作者： Z.iqbal,Zaffar Mehmood Bilal Ahmad Department of Mathematics Faculty of Sciences HITEC University Taxila 44000 Pakistan

This communication is devoted to analyze elastic deformation on electrically conducted viscoelastic fluid in the presence of viscous dissipation effects. Non-linear analysis is computed through exact solutions for velocity,temperature and concentration profiles. Special emphasis is provided for elastic deformation in the presence of magnetohydrodynamics effects. Concentration profile is discussed significantly in the presence constructive and destructive chemical reaction. Results are displayed through graphs and discussed for physical parameters that are used in present analysis. Notable findings include that temperature and thermal boundary layer thickness is an increasing function of Prandtl number and a decreasing function of elastic deformation. In addition, heat transfer rate is enhanced by increasing the conjugate parameter(γ) which measures the strength of surface heating.

关键词： closed form solutions heat and mass transfer viscous dissipation elastic deformation MHD Newtonian heating

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Enhanced catalytic features of sol-gel immobilized MnP isolated from solid state culture of Pleurotus ostreatus IBL-02

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Chinese Chemical Letters 2013年第4期24卷 344-346页

作者： Muhammad Asgher Hafiz Muhammad Nasir iqbal Industrial Biotechnology Laboratory Department of Chemistry and BiochemistryUniversity of Agriculture

An indigenous and industrially important manganese peroxidase （MnP） isolated from solid state culture of Pleurotus ostreatus IBL-02 was 2.1-fold purified and immobilized using sol-gel matrix of trimethoxysilane and proplytetramethoxysilane. Lower KM, higher Vmax, hyper-activation, enhanced acidic and thermal stability up to 70 ℃, were the improved]enhanced catalytic features of the presently sol-gel immobilized MnP. A maximum of 100% decolorization was achieved within a short time period for the different real dyes containing textile industry effluents i.e. Nishat textile （NIT）, K＆N textile （KIT）, Sitara textile （SIT）, and Crescent textile （CRT）.

关键词： P. ostreatus IBL-02MnPSol-gelTextile effluentDecolorization

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Brain Tumor Segmentation in Multimodal MRI Using U-Net Layered Structure

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Computers, Materials & Continua 2023年第3期74卷 5267-5281页

作者： Muhammad Javaid iqbal Muhammad Waseem iqbal Muhammad Anwar Muhammad Murad Khan Abd Jabar Nazimi Mohammad Nazir Ahmad Department of Information Technology The Superior UniversityLahorePakistan Department of Software Engineering The Superior UniversityLahorePakistan Department of Information Sciences Division of Science and TechnologyUniversity of EducationLahorePakistan Department of Computer Science Government College UniversityFaisalabadPakistan Deptment of Oral and Maxillofacial Surgery Faculty of DentistryUniversiti Kebangsaan MalaysiaKuala LumpurMalaysia Institute of IR4.0 Universiti Kebangsaan MalaysiaBangiSelangorMalaysia

The brain tumour is the mass where some tissues become old or damaged,but they do not die or not leave their *** brain tumour masses occur due to malignant *** tissues must die so that new tissues are allowed to be born and take their *** segmentation is a complex and time-taking problem due to the tumour’s size,shape,and appearance *** finding such masses in the brain by analyzing Magnetic Resonance Images(MRI)is a crucial task for experts and *** could not work for large volume images simultaneously,and many errors occurred due to overwhelming image *** main objective of this research study is the segmentation of tumors in brain MRI images with the help of digital image processing and deep learning *** research study proposed an automatic model for tumor segmentation in MRI *** proposed model has a few significant steps,which first apply the pre-processing method for the whole dataset to convert Neuroimaging Informatics Technology Initiative(NIFTI)volumes into the 3D NumPy *** the second step,the proposed model adopts U-Net deep learning segmentation algorithm with an improved layered structure and sets the updated *** the third step,the proposed model uses state-of-the-art Medical Image Computing and Computer-Assisted Intervention(MICCAI)BRATS 2018 dataset withMRI modalities such as T1,T1Gd,T2,and Fluidattenuated inversion recovery(FLAIR).Tumour types in MRI images are classified according to the tumour *** of these masses carried by state-of-the-art approaches such that the first is enhancing tumour(label 4),edema(label 2),necrotic and non-enhancing tumour core(label 1),and the remaining region is label 0 such that edema(whole tumour),necrosis and *** proposed model is evaluated and gets the Dice Coefficient(DSC)value for High-grade glioma(HGG)volumes for their test set-a,test set-b,and test set-c 0.9795, 0.9855 and 0.9793, respectively.

关键词： Brain tumour segmentation magnetic resonance images modalities dice coefficient low-grade glioma U-Net

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