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Geochemical indices of soil development on basalt rocks in arid to sub-humid climosequence of Central Iran

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Journal of Mountain Science 2020年第7期17卷 1652-1669页

作者： ahmad HEIDARI Alireza RAHEB Soil Science Department College of Agriculture and Natural ResourcesUniversity of TehranKarajP.O.Box 4111Iran

Quantitative weathering indices are efficient tools in determining the soil development from the underlying *** order to evaluate the effects of climate on the soils developed under an arid to sub-humid climosequence in central Iran,twenty soil-development indices were *** samples from six pedons were analyzed for routine physico-chemical and geochemical analyses using X-ray fluorescence(XRF).The lowest and highest calculated soil development indices were observed in the arid and sub-humid regions *** the studied indices,fifteen indices showed similar trends concerning the intensity of *** consistency of such trends reveals the feasibility of using these indices to evaluate basalt weathering rate and soil development in arid,semi-arid and sub-humid *** study demonstrated that,among the evaluated weathering indices,the Weathering Index of Parker(WIP)and mass transfer coefficient(τ)were the most proper indices for predicting basalt weathering *** is due to the fact that these indices use the highly mobile earth elements which are the most sensitive elements in basalt chemical *** calculated indices were subdivided into three subgroups including the ratios of mobile/immobile,mobile/mobile and immobile/mobile elements based on the elements used in their *** state of soil evolution was more accurately predicted compared to the other subgroups using the mobile/immobile subgroup of ***,the weathering indices calculated using the mobile elements are better indicators of weathering intensity,soil formation and the exogenous processes across the arid to sub-humid climosequence.

关键词： Basalt Climosequence Geochemical properties Aridisols Mollisols Inceptisols

An Optimized Method for Accounting Information in Logistic Systems

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Computer Systems Science & Engineering 2023年第5期45卷 1595-1609页

作者： ahmad Mohammed Alamri ahmad Ali AlZubi Administrative Sciences Department Community CollegeKing Saud UniversityRiyadhSaudi Arabia Computer Science Department Community CollegeKing Saud UniversityP.O.Box 28095Riyadh11437Saudi Arabia

In the era of rapid information development,with the popularity of computers,the advancement of science and technology,and the ongoing expansion of IT technology and business,the enterprise resource planning(ERP)system has evolved into a platform and a guarantee for the fulfilment of company management procedures after long-term *** of developments in information technology,most manual accounting procedures are being replaced by computerized Accounting Information Systems(AIS),which are quicker and more *** primary factors influencing the decisions of logistics firm trading parties are investigated in order to enhance the design of decision-supporting modules and to improve the performance of logistics enterprises through *** paper proposed a novel approach to calculate the weights of each information element in order to establish their important *** main purpose of this research is to present a quantitative analytic approach for determining the important information of logistics business collaboration ***,the idea of total orders and the significant degrees stated above are used to identify the optimal order of all information *** the three ways of marginal revenue,marginal cost,and business matching degree,the information with cumulative weights is which is deployed to form the data from the intersection of the best *** has the ability to drastically reduce the time and effort required to create a logistics business control/decision-making system.

关键词： Accounting information systems decisions systems corporate accounting logistic system

Accelerated D-Dimensional Compactified Universe in Gauss-Bonnet-Dilatonic Scalar Gravity from D-Brane/M-Theory

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Chinese Physics Letters 2008年第8期25卷 2785-2788页

作者： EL-NABULSI ahmad Rami Department of Nuclear and Energy Engineering Cheju National University Ara-dong 1 Jeju 690-756 South Korea

We discuss a particular d-dimensional Gauss- Ronnet-dilatonie universe compactified on S^1 motivated from Mtheory. We examine the time-evolution of the dynamical equations where many interesting consequences are revealed and discussed in some details. Under reasonable conditions, the discussed model can provide a mechanism to realize, in higher-dimensions （d 〉 4）, the accelerated expansion of the universe in the presence of dark energy, without the presence of phantom energy and without the contraction of some internal dimension.

关键词： COSMOLOGICAL CONSTANT CHAPLYGIN-GAS DARK ENERGY QUINTESSENCE SUPERNOVAE PLANETS OMEGA

Extra-Dimensional Cosmology with a Traversable Wormhole

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Chinese Physics Letters 2009年第9期26卷 37-40页

作者： EL-NABULSI ahmad Rami Department of Nuclear and Energy Engineering Cheju National University Ara-dong 1 Jeju 690-756 South Korea

We discuss many interesting and attractive features of a higher-dimensional cosmology with a static traversable wormhole dominated by a variable effective cosmological constant depending on the scale factor aft） as A... 详细信息

关键词： sea surface nonliear interaction numerical method

Suppression and synchronization of chaos in uncertain time-delay physical system

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 416-437页

作者： Israr ahmad Muhammad Shafiq Department of Preparatory Studies Centre University of Technology and Applied SciencesNizwaOman Department of Electrical and Computer Engineering Sultan Qaboos UniversityOman

The mechanical horizontal platform(MHP)system exhibits a rich chaotic *** chaotic MHP system has applications in the earthquake and offshore *** article proposes a robust adaptive continuous control(RACC)*** investigates the control and synchronization of chaos in the uncertain MHP system with time-delay in the presence of unknown state-dependent and time-dependent *** closed-loop system contains most of the nonlinear terms that enhance the complexity of the dynamical system;it improves the efficiency of the *** proposed RACC approach(a)accomplishes faster convergence of the perturbed state variables(synchronization errors)to the desired steady-state,(b)eradicates the effect of unknown state-dependent and time-dependent disturbances,and(c)suppresses undesirable chattering in the feedback control *** paper describes a detailed closed-loop stability analysis based on the Lyapunov-Krasovskii functional theory and Lyapunov stability *** provides parameter adaptation laws that confirm the convergence of the uncertain parameters to some constant *** computer simulation results endorse the theoretical findings and provide a comparative performance.

关键词： chaotic horizontal platform system chaos suppression chaos synchronization robust adaptive control Lyapunov stability theory

The impact of Persian oak (Quercus brantii Lindl.) on soil characteristics in a declining forest

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Journal of Forestry Research 2020年第6期31卷 2359-2366页

作者： Reza Soleimani ahmad Hosseini Crop and Horticultural Science Research Department Ilam Agricultural and Natural Resources Research and Education CenterAREEOIlamIran Forests and Rangelands Research Department Ilam Agricultural and Natural Resources Research and Education CenterAREEOIlamIran

Root activity has an important impact on soil development but we have little knowledge of the interaction of the root zone and soil genetic *** aim of this investigation was to study the interactions between soil chemical characteristics and root zone processes in a declining Persian oak forest(Quercus brantii Lindl.).A randomized complete block design was used to investigate the long-term eff ect of Persian oak on soil horizons,and the chemical and biological properties in two soil zones(under and outside the canopy).Results indicate that the rhizosphere zone had signifi cantly higher total organic carbon(TOC)than outside the canopy soil in the upper soil *** subsurface horizons,water-extractable organic carbon values were signifi cantly higher in rhizosphere than in non-rhizospheric *** biomass carbon(MBC)values in the rhizospheric zone decreased from the fi rst to the second *** MBC/TOC ratio indicated signifi-cant diff erences between the rhizosphere and soils outside of the canopy,with the exception of the subsurface *** the subsurface horizon of the rhizosphere,there was greater respiration of organic carbon(ΣCO 2/TOC)than in outside of canopy *** addition,root processes infl uenced pH,nitrogen fractions,and availability of phosphorus,potassium,iron,zinc and *** erences in soil characteristics between rhizospheric and non-rhizospheric zones were signifi cant in surface horizons due to higher root density than in deeper soil *** fi ndings indicate that Persian oak(Quercus brantii Lindl.)roots infl uenced the main soil chemical properties,even in calcareous soils.

关键词： Declining forest Persian oak Rhizosphere Soil horizons

Analysis of the seventh-order Caputo fractional KdV equation:applications to the Sawada-Kotera-Ito and Lax equations

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Communications in Theoretical Physics 2023年第8期75卷 14-24页

作者： Shabir ahmad Sayed Saifullah Department of Mathematics University of MalakandChakdaraDir LowerKhyber PakhtunkhwaPakistan

In this study,we investigate the seventh-order nonlinear Caputo time-fractional KdV *** suggested model's solutions,which have a series form,are obtained using the hybrid ZZ-transform under the aforementioned fractional *** proposed approach combines the homotopy perturbation method(HPM)and the *** consider two specific examples with suitable initial conditions and find the series solution to test their *** demonstrate the utility of the presented technique,we explore its applications to the fractional Sawada–Kotera–Ito problem and the Lax *** observe the impact of a few fractional orders on the wave solution evolution for the problems under *** provide the efficiency and reliability of the ZZHPM by calculating the absolute error between the series solution and the exact solution of both the Sawada–Kotera–Ito and Lax *** convergence and uniqueness of the solution are portrayed via fixed-point theory.

关键词： seventh-order KdV equation soliton homotopy perturbation method

Photometry and spectroscopy ofⅡPeg,IM Peg and UX Ari

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Research in Astronomy and Astrophysics 2018年第9期18卷 79-88页

作者： Ajaz ahmad Dar Padmakar Singh Parihar Manzoor ahmad Malik Department of Physics University of KashmirHazratbal 190006 Srinagar-J&KIndia Department of Physics Islamia College of Science and CommerceHawalSrinagar-19002J&KIndia Indian Institute of Astrophysics Koramagala-560034BangaloreIndia

Ⅴ band photometry of three RS CVn stars,Ⅱ Peg, IM Peg and UX Ari, is carried out to study the physical properties of these variables. We verified the significant and regular optical photometric variability to be present in all three stars. The strong photometric variability and emission of Hα and Ca Ⅱ H ＆ K using high resolution optical spectroscopy with the Hanle Echelle Spectrograph （HESP）, which operates in conjunction with the Himalayan Chandra Telescope, verify the strong chromospheric activity which is present in RS CVn stars. The photometric studies of Ⅱ Peg, UX Ari and IM Peg were subjected to light curve analysis for spot parameters using a two-starspot model.

关键词： RS CVn star spots chromospherically active

Color-flavor dependence of the Nambu-Jona-Lasinio model and QCD phase diagram

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Chinese Physics C 2022年第8期46卷 128-140页

作者： Aftab ahmad Ali Murad Institute of Physics Gomal University29220D.I.KhanKhyber PakhtunkhawPakistan

We study the dynamical chiral symmetry breaking/restoration for various numbers of light quarks flavors N_(f) and colors N_(c) using the Nambu-Jona-Lasinio(NJL) model of quarks in the Schwinger-Dyson equation framework,dressed with a color-flavor dependence of effective *** fixed N_(f)=2 and varying N_(c),we observe that the dynamical chiral symmetry is broken when N_(c) exceeds its critical value N_(c)^(c)≈*** a fixed N_(c)=3 and varying N_(f),we observe that the dynamical chiral symmetry is restored when Nf reaches its critical value N_r^(c)≈*** interplay is observed between N_(c) and N_(f),i.e.,larger values of N_(c) tend to strengthen the dynamical generated quark mass and quark-antiquark condensate,while higher values of N_(f) suppress both *** further sketch the quantum chromodynamics(QCD) phase diagram at a finite temperature T and quark chemical potential μ for various N_(c) and N_(f).At finite T and μ,we observe that the critical number of colors N_(c)^(c) is enhanced,whereas the critical number of flavors N_(f)^(c) is suppressed as T and μ ***,the critical temperature T_(c),μ_(c),and co-ordinates of the critical endpoint(T_(c)^(E),μ_(c)^(E)) in the QCD phase diagram are enhanced as N_(c) increases and suppressed when N_(f) *** findings agree with the lattice QCD and Schwinger-Dyson equations predictions.

关键词： chiral symmetry breaking Schwinger-Dyson equation finite temperature and density QCD phase diagram