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Bayesian model predicts the aboveground biomass of Caragana microphylla in sandy lands better than OLS regression models

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Journal of Plant Ecology 2020年第6期13卷 732-737页

作者： Yi Tang arshad Ali Li-Huan Feng School of Life Science Liaoning UniversityShenyang 110036LiaoningChina Department of Forest Resources Management College of ForestryNanjing Forestry UniversityNanjing 210037JiangsuChina Co-Innovation Center for Sustainable Forestry in Southern China Nanjing Forestry UniversityNanjing 210037JiangsuChina

Aims In forest ecosystems,different types of regression models have been frequently used for the estimation of aboveground biomass,where Ordinary Least Squares(OLS)regression models are the most common prediction ***,the relative performance of Bayesian and OLS models in predicting aboveground biomass of shrubs,especially multi-stem shrubs,has relatively been less studied in *** In this study,we developed the biomass prediction models for Caragana microphylla *** is a widely distributed multi-stems shrub,and contributes to the decrease of wind erosion and the fixation of sand dunes in the Horqin Sand Land,one of the largest sand lands in *** developed six types of formulations under the framework of the regression models,and then,selected the best model based on specific ***,we estimated the parameters of the best model with OLS and Bayesian methods with training and test data under different sample sizes with the bootstrap ***,we compared the performance of the OLS and Bayesian models in predicting the aboveground biomass of *** Findings The performance of the allometric equation(power=1)was best among six types of equations,even though all of those models were *** results showed that mean squared error of test data with non-informative prior Bayesian method and the informative prior Bayesian method was lower than with the OLS *** the tested predictors(*** height and basal diameter),we found that basal diameter was not a significant predictor either in OLS or Bayesian methods,indicating that suitable predictors and well-fitted models should be seriously *** study highlights that Bayesian methods,the bootstrap method and the type of allometric equation could help to improve the model accuracy in predicting shrub biomass in sandy lands.

关键词： bootstrap Caragana microphylla Horqin Sandy Land mean squared error prior information

On Some Ev-Degree and Ve-Degree Dependent Indices of Benes Network and Its Derived Classes

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Computer Modeling in Engineering & Sciences 2023年第5期135卷 1685-1699页

作者： Wenhu Wang Hibba arshad Asfand Fahad Imran Javaid School of Software Pingdingshan UniversityPingdingshanChina College of Computing and Information Technologies National UniversityManilaPhilippines Henan International Joint Laboratory for Multidimensional Topology and Carcinogenic Characteristics Analysis of Atmospheric Particulate Matter PM2.5 PingdingshanChina Centre for Advanced Studies in Pure and Applied Mathematics Bahauddin Zakariya UniversityMultanPakistan

One of the most recent developments in the field of graph theory is the analysis of networks such as Butterfly networks,Benes networks,Interconnection networks,and David-derived networks using graph theoretic *** topological indices(TIs)have been widely used as graph invariants among various graph theoretic *** structure activity relationships(QSAR)and quantitative structure property relationships(QSPR)need the use of *** structure-based parameters,such as the degree and distance of vertices in graphs,contribute to the determination of the values of *** other recently introduced novelties,the classes of ev-degree and ve-degree dependent TIs have been extensively explored for various graph *** current research focuses on the development of formulae for different ev-degree and ve-degree dependent TIs for s−dimensional Benes network and certain networks derived from *** the end,a comparison between the values of the TIs for these networks has been presented through graphical tools.

关键词： Topological indices ev-degree ve-degree butterfly network benes network

Speciesα-diversity promotes butβ-diversity restricts aboveground biomass in tropical forests,depending on stand structure and environmental factors

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Journal of Forestry Research 2023年第5期34卷 889-901页

作者： Umar Aftab Abbasi Eskil Mattsson Sarath Premalal Nissanka arshad Ali Forest Ecology Research Group College of Life SciencesHebei UniversityBaoding 071002People’s Republic of China IVL Swedish Environmental Research Institute Aschebergsgatan 4441133 GothenburgSweden Gothenburg Global Biodiversity Centre(GGBC) GothenburgSweden Department of Crop Science Faculty of AgricultureUniversity of PeradeniyaPeradeniyaSri Lanka

Forest plays a vital role in the global biogeochemical cycles through a high rate of carbon sequestration and harboring ***,local species diversity is declining while also becoming increasingly homogenized across *** eff ects of local biotic processes(e.g.,speciesα-diversity and stand structural heterogeneity)and environmental factors on aboveground biomass(AGB)have been widely tested,there is a huge knowledge gap for the eff ect of regional biotic processes(i.e.,taxonomic and functionalβ-diversity)in ***,we hypothesized that regional and local environmental factors along with biotic processes jointly regulate AGB through species shifts in tropical *** piecewise structural equation modeling(pSEM),we linked climatic water availability,soil fertility,stand structural heterogeneity(either tree DBH inequality,height inequality,or stand density),speciesα-diversity,taxonomic or functionalβ-diversity(and its two components;β-turnover andβ-richness),and AGB across 189 inventory plots in tropical forests of Sri *** fertility and climatic water availability shaped local and regional biotic *** structural heterogeneity promoted speciesα-diversity but declinedβ-diversity(but increasedβ-taxonomic turnover).Speciesα-diversity and stand structural heterogeneity promoted AGB whereas taxonomic and functionalβ-diversity declined(butβ-taxonomic turnover increased)*** relationships of AGB with speciesα-diversity andβ-diversity varied from signifi cant to nonsignifi cant positive depending on the specifi c combinations of stand structural heterogeneity metrics *** study shows that local biotic processes could increase AGB due to the local and regional niche complementarity eff ect whereas the regional biotic processes could restrict AGB due to the regional selection or functional redundancy eff ect under favorable environmental *** argue that biotic homogenization,as well as drought conditions,ma

关键词： Biodiversity Biotic homogenization Climate Forest functioning Soil Tree size

Heat Transfer of Casson Fluid over a Vertical Plate with Arbitrary Shear Stress and Exponential Heating

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Computers, Materials & Continua 2022年第4期71卷 1025-1034页

作者： Dolat Khan Gohar Ali arshad Khan Ilyas Khan 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 Minh City72915Vietnam

The basic objective of this work is to study the heat transfer of Casson fluid of non-Newtonian *** fluid is considered over a vertical plate such that the plate exhibits arbitrary wall shear stress at the *** transfers due to exponential plate heating and natural convection are due to buoyancy ***(MHD)analysis in the occurrence of a uniform magnetic field is also *** medium over the plate is porous and hence Darcy’s law is *** governing equations are established for the velocity and temperature fields by the usual Boussinesq *** problem is first written in dimensionless form using some useful non-dimensional quantities and then *** exact analysis is performed and hence solutions via integral transform are *** analysis of various pertinent parameters on temperature distribution and velocity field are reported *** is found that pours medium permeability parameter retards the fluid motion whereas,velocity decreases with increasing magnetic *** and temperature decrease with increasing Prandtl number whereas the Grashof number enhances the fluid ***,it is concluded from this study that the results obtained here are more general and in a limiting sense several other solutions can be *** Newtonian fluid results can be easily established by taking the Casson parameter infinitely large i.e.,whenβ→∞.

关键词： Heat transfer casson fluid shear stress natural convection

Hydrological Response to Environment Change in Himalayan Watersheds: Assessment from Integrated Modeling Approach

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Journal of Mountain Science 2015年第4期12卷 972-982页

作者： Zulfiqar AHMAD arshad ASHRAF Muhammad ZAHEER Humaira BASHIR Department of Earth Sciences Quaid-i-Azam University National Agricultural Research Center China University of Geosciences School of Environmental Studies

Land use changes such as deforestation,increase in cropping or grazing areas and built-up land, likely modify the water balance and land surface behavior in the Himalayan *** integrated approach of hydrological and hydraulic modeling was adopted for comparative analysis of hydrological pattern in three Himalayan watersheds ***,Rawal and Simly situated in the Northern territory of *** rainfall-runoff model SWAT- Soil and water assessment tool and Hydro CAD were calibrated for the selected *** correlation analysis of the precipitation data of two climate stations *** and Islamabad, with the discharge data of three rivers was utilized to select best suitable input precipitation data for Hydro CAD rainfall-runoff *** peak flood hydrograph were generated using Hydro CAD runoff to optimize the basin parameters like CN, runoff volume, peak flows of the three *** hydrological response of the Rawal watershed was studied as a case study to different scenarios of land use change using SWAT *** scenario of high deforestation indicated a decline of about 6.3% in the groundwater recharge tostream while increase of 7.1% in the surface runoff has been observed under the scenario of growth in urbanization in the recent *** integrated modeling approach proved helpful in investigating the hydrological behavior under changing environment at watershed level in the Himalayan region.

关键词： Hydrological modeling Deforestation Soan River Simly Khanpur watershed Land use

A visual photothermal paper sensor for H_2S recognition through rational modulation LSPR wavelength of plasmonics

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Science China Chemistry 2018年第3期61卷 368-374页

作者： Hui Wang Jiabin Cui Anila arshad Suying Xu Leyu Wang State Key Laboratory of Chemical Resource Engineering School of Science Beijing University of Chemical Technology

It is known that the localized surface plasmon resonance(LSPR) wavelength of plasmonics is highly dependent on compositions and geometry of plasmonics as well as the surrounding environments. Here, monodispersed Au@Ag core-shell nanoparticles(Au@Ag NPs) were prepared by carefully optimizing the shell thickness of Au@Ag NPs, and the presence of hydrogen sulfide(H_2 S) would significantly alter the LSPR wavelength. On the basis of this, a photothermal paper sensor for on-site recognition of H_2 S was constructed with a visual detection limit of 12.8 ng/L.

关键词： localized surface plasmon resonance Au@Ag NPs H2S detection photothermal paper sensor

Effect of thermomechanical cyclic quenching and tempering treatments on microstructure,mechanical and electrochemical properties of AISI 1345 steel

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International Journal of Minerals,Metallurgy and Materials 2021年第4期28卷 688-698页

作者： Muhammad Arslan Hafeez Ameeq Farooq Kaab Bin Tayyab and Muhammad Adnan arshad School of Civil and Environmental Engineering National University of Sciences and TechnologyIslamabad 44000Pakistan Department of Metallurgy&Materials Engineering University of the Punjab54590 LahorePakistan

Thermomechanical cyclic quenching and tempering(TMCT)can strengthen steels through a grain size reduction *** effect of TMCT on microstructure,mechanical,and electrochemical properties of AISI 1345 steel was *** samples heated to 1050℃,rolled,quenched to room temperature,and subjected to various cyclic quenching and tempering heat treatments were named TMCT-1,TMCT-2,and TMCT-3 samples,*** analysis revealed that microstructures of all the treated samples contained packets and blocks of well-refined lath-shaped martensite and retained austenite phases with varying grain sizes(2.8–7.9μm).Among all the tested samples,TMCT-3 sample offered an optimum combination of properties by showing an improvement of 40%in tensile strength and reduced 34%elongation compared with the non-treated *** results were in good agreement with mechanical tests as the TMCT-3 sample exhibited a 51%improvement in indentation hardness with almost identical reduced elastic modulus compared with the non-treated *** electrochemical properties were analyzed in 0.1 M NaHCO_(3) solution by potentiodynamic polarization and electrochemical impedance *** a result of TMCT,the minimum corrosion rate was 0.272 mm/a,which was twenty times less than that of the nontreated *** impedance results showed the barrier film mechanism,which was confirmed by the polarization results as the current density decreased.

关键词： thermomechanical treatment cyclic heat-treatment nanoindentation potentiodynamic polarization electrochemical impedance spectroscopy

Adsorption of Cationic Laser Dye onto Polymer/Surfactant Complex Film

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Chinese Journal of Chemical Physics 2011年第3期24卷 348-352,I0004页

作者： Pabitra Kuiilar Paul Syed arshad Hussain Debajyoti Bhattacharjee Mrinal Pal 印度贾达沃普尔大学物理系尔各答-700032 印度特里普拉邦大学物理系 Suryamaninagar-799130 印度中央机械工程研究所杜尔加布尔-713209

Fabrication of complex molecular films of organic materials is one of the most important issues in modern nanoscience and nanotechnology. Soft materials with flexible properties have been given much attention and can be obtained through bottom up processing from functional molecules, where self-assembly based on supramolecular chemistry and designed assembly have become crucial processes and technologies. In this work, we report the successful incorporation of cationic laser dye rhodamine 6G abbreviated as R6G into the pre-assembled polyelectrolyte/surfactant complex film onto quartz substrate by electrostatic adsorption technique. Poly（allylamine hydrochloride）（PAH） was used as polycation and sodium dodecyl sulphate （SDS） was used as anionic surfactant. UV-Vis absorption spectroscopic characterization reveals the formation of only H-type aggregates of R6G in their aqueous solution and both H- and J-type aggregates in PAH/SDS/R6G complex layer-bylayber films as well as the adsorption kinetics of R6G onto the complex films. The ratio of the absorbance intensity of two aggregated bands in PAH/SDS/R6G complex fihns is merely independent of the concentration range of the SDS solution used to fabricate PAH/SDS complex self-assembled films. Atomic force microscopy reveals the formation of R6G aggregates in PAH/SDS/R6G complex films.

关键词： Layer-by-layer self assembly Cationic dye Electrostatic adsorption UV-Vis absorption spectroscopy

A numerical framework for the approximate solution of fractional tumor-obesity model

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International Journal of Modeling, Simulation, and Scientific Computing 2019年第1期10卷 106-118页

作者： Sadia arshad Dumitru Baleanu Ozlem Defterli Shumaila Department of Mathematics COMSATS University Islamabad LahorePunjab 54000Pakistan Department of Mathematics and Computer Sciences Cankaya University Ankara 06530Turkey

In this paper,we have proposed the efficient numerical methods to solve a tumor-obesity model which involves two types of the fractional operators namely Caputo and CaputoFabrizio(CF).Stability and convergence of the proposed schemes using Caputo and CF fractional operators are *** simulations are carried out to investigate the effect of low and high caloric diet on tumor dynamics of the generalized *** perform the numerical simulations of the tumor-obesity model for different fractional order by varying immune response rate to compare the dynamics of the Caputo and CF fractional operators.

关键词： Tumor-obesity model numerical approximation stability and convergence analysis