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Acta Mathematica Scientia 2011年第6期31卷 2122-2130页

作者： bashir Ahmad Juan J. Nieto Ahmed Alsaedi Department of Mathematics Faculty of ScienceKing Abdulaziz University Departamento de Anlisis Matemtico Facultad de MatemticasUniversidad de Santiago de Compostela

In this paper, we study a boundary value problem of nonlinear fractional dif- ferential equations of order q （1 〈 q 〈 2） with non-separated integral boundary conditions. Some new existence and uniqueness results are obtained by using some standard fixed point theorems and Leray-Schauder degree theory. Some illustrative examples are also presented. We extend previous results even in the integer case q = 2.

关键词： fractional differential equations non-separated integral boundary conditions contraction principle Krasnoselskii's fixed point theorem LeraySchauder degree

Modelling and analysis of an 80-MW parabolic trough concentrated solar power plant in Sudan

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Clean Energy 2022年第3期6卷 512-527页

作者： Abdallah Adil Awad bashir MustafaÖzbey Department of Mechanical Engineering Ondokuz Mayis UniversitesiSamsun 55139Turkey

Concentrated solar power plants can play a significant role in alleviating Sudan’s energy *** plants can be established and implemented in Sudan,as their potential is considerably high due to the climate conditions in *** study investigates the design of a parabolic trough concentrated solar power plant in Sudan and analyzes its technical and economic *** simulation of the plant’s model used System Advisor Model(SAM)*** determine the best location for the construction of the plant,data from 15 cities in Sudan were compared with each other based on their solar radiation and land *** Halfa,a city in the northern region of Sudan,was chosen as the location due to its good topographical properties and climate *** results show that the proposed plant can generate 281.145 GWh of electricity annually with a capacity factor of 40.1%and an overall efficiency of 15%.Additionally,a simple cost analysis of the plant indicates a levelized cost of electricity of 0.155$/*** the study results are consistent with the characteristics of similar plants,the proposed plant is considered technically and economically feasible under the conditions at its location.

关键词： solar energy concentrated solar power parabolic trough collector System Advisor Model(SAM)simulation

Optimal Control Model for the Transmission of Novel COVID-19

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Computers, Materials & Continua 2021年第3期66卷 3089-3106页

作者： Isa Abdullahi Baba bashir Ahmad Nasidi Dumitru Baleanu Department of Mathematical Sciences Bayero University KanoNigeria Department of Mathematics Cankaya UniversityAnkara06530Turkey Institute of Space Sciences BucharestRomania Department of Medical Research China Medical University HospitalTaichungTaiwan

As the corona virus(COVID-19)pandemic ravages socio-economic activities in addition to devastating infectious and fatal consequences,optimal control strategy is an effectivemeasure that neutralizes the scourge to its lowest *** this paper,we present a mathematical model for the dynamics of COVID-19,and then we added an optimal control function to the model in order to effectively control the *** incorporate three main control efforts(isolation,quarantine and hospitalization)into the model aimed at controlling the spread of the *** efforts are further subdivided into five functions;u1(t)(isolation of the susceptible communities),u2(t)(contact track measure by which susceptible individuals with contact history are quarantined),u3(t)(contact track measure by which infected individualsare quarantined),u4(t)(control effort of hospitalizing the infected I1)and u5(t)(control effort of hospitalizing the infected I2).We establish the existence of the optimal control and also its characterization by applying Pontryaging maximum *** disease free equilibrium solution(DFE)is found to be locally asymptotically stable and subsequently we used it to obtain the key parameter;basic reproduction *** constructed Lyapunov function to which global stability of the solutions is *** simulations show how adopting the available control measures optimally,will drastically reduce the infectious populations.

关键词： COVID-19 optimal control Pontryaging maximum principle mathematical model existence of control stability analysis

Bioengineering liver tissue by repopulation of decellularised scaffolds

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World Journal of Hepatology 2023年第2期15卷 151-179页

作者： zeeshan Afzal Emmanuel Laurent Huguet Department of Surgery Addenbrookes HospitalNIHR Comprehensive Biomedical Research and Academic Health Sciences CentreCambridge University Hospitals NHS Foundation TrustCambridge CB20QQUnited Kingdom

Liver transplantation is the only curative therapy for end stage liver disease,but is limited by the organ shortage,and is associated with the adverse consequences of *** of decellularised whole organ scaffolds with appropriate cells of recipient origin offers a theoretically attractive solution,allowing reliable and timely organ sourcing without the need for *** methodologies vary widely but seek to address the conflicting objectives of removing the cellular component of tissues whilst keeping the 3D structure of the extra-cellular matrix intact,as well as retaining the instructive cell fate determining biochemicals contained *** scaffold recellularisation has progressed from small rodent in vitro studies to large animal in vivo perfusion models,using a wide range of cell types including primary cells,cell lines,foetal stem cells,and induced pluripotent stem *** these models,a limited but measurable degree of physiologically significant hepatocyte function has been reported with demonstrable ammonia metabolism in *** repopulation and function have been restricted by challenges relating to the culture and propagations of cholangiocytes,though advances in organoid culture may help address *** vasculature repopulation has enabled sustainable blood perfusion in vivo,but with cell types that would limit clinical applications,and which have not been shown to have the specific functions of liver sinusoidal endothelial *** cell groups such as Kupffer cells and stellate cells have not been *** by repopulation of decellularised scaffolds has significantly progressed,but there remain significant experimental challenges to be addressed before therapeutic applications may be envisaged.

关键词： Regenerative Bioengineering Scaffolds Liver Decellularisation Recellularisation

A NONLOCAL HYBRID BOUNDARY VALUE PROBLEM OF CAPUTO FRACTIONAL INTEGRO-DIFFERENTIAL EQUATIONS

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Acta Mathematica Scientia 2016年第6期36卷 1631-1640页

作者： bashir AHMAD Sotiris K.NTOUYAS Jessada TARIBOON Nonlinear Analysis and Applied Mathematics(NAAM)-Research Group Department of MathematicsFaculty of ScienceKing Abdulaziz University Department of Mathematics University of Ioannina Nonlinear Dynamic Analysis Research Center Department of MathematicsFaculty of Applied ScienceKing Mongkut’s University of Technology North Bangkok

In this paper, we discuss the existence of solutions for a nonlocal hybrid boundary value problem of Caputo fractional integro-differential equations. Our main result is based on a hybrid fixed point theorem for a sum... 详细信息

关键词： Caputo fractional derivative integral hybrid fixed point theorem

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

Computational engineering analysis of external geometrical modifications on MQ-1 unmanned combat aerial vehicle

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Chinese Journal of Aeronautics 2020年第4期33卷 1154-1165页

作者： Prakash BAGUL zeeshan A.RANA Karl W.JENKINS LászlóKoNoZSY Centre for Computational Engineering Sciences Cranfield UniversityCranfield MK43 OALUnited Kingdom

This paper focuses on the effects of external geometrical modifications on the aerodynamic characteristics of the MQ-1 predator Unmanned Combat Aerial Vehicle(UCAV)using computational fluid *** investigations are performed for 16 flight conditions at an altitude of7.6 km and at a constant speed of 56.32 m/*** models are analysed,namely the baseline model and the model with external geometrical modifications installed on *** the models are investigated for various angles of attack from-4°to 16°,angles of bank from 0°to 6°and angles of yaw from 0°to 4°.Due to the unavailability of any experimental(wind tunnel or flight test)data for this UCAV in the literature,a thorough verification of calculations process is presented to demonstrate confidence level in the numerical *** analysis quantifies the loss of lift and increase in drag for the modified version of the MQ-1 predator UCAV along with the identification of stall *** improvement(in drag)of up to 96%has been obtained by relocating external modifications,whereas global drag force reduction of roughly 0.5%is *** effects of external geometrical modifications on the control surfaces indicate the blanking phenomenon and reduction in forces on the control surfaces that can reduce the aerodynamic performance of the UCAV.

关键词： Aerodynamics CFD Geometrical modifications MQ-1 predator Turbulent flows Unmanned combat aerial vehicle Unsteady Reynoldsaveraged Navier-Stokes

DYNAMICS OF A HEPATITIS B MODEL WITH SATURATED INCIDENCE

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Acta Mathematica Scientia 2018年第6期38卷 1731-1750页

作者： Liya LIU Daqing JIANG Tasawar HAYAT bashir AHMAD. School of Petroleum Engineering China University of Petroleum Qingdao 266580 China College of Science China University of Petroleum Qingdao 266580 China Nonlinear Analysis and Applied Mathematics (NAAM)-Research Group King Abdulaziz University Jeddah Saudi Arabia Department of Mathematics Quaid-I-Azam University45320 Islamabad 44000 Pakistan

In this article, we present a hepatitis B epidemic model with saturated *** dynamic behaviors of the deterministic and stochastic system are studied. To thisend, we first establish the local and global stability conditions of the equilibrium of thedeterministic model. Second, by constructing suitable stochastic Lyapunov functions, thesufficient conditions for the existence of ergodic stationary distribution as well as extinctionof hepatitis B are obtained.

关键词： hepatitis B model Lyapunov function stability stationary distribution ex-tinction

Preparation and antibacterial activities of metal complexes of norfloxacin

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Journal of Chinese Pharmaceutical Sciences 2021年第10期30卷 838-844页

作者： Ahsan Zamir Siddiqi Muneeba Akhtar Agha zeeshan Mirza Research Institute of Pharmaceutical Sciences Department of Pharmaceutical ChemistryFaculty of PharmacyUniversity of KarachiKarachi-75270Pakistan Highnoon Laboratories Limited LahorePakistan Department of Pharmaceutics Faculty of PharmacyUniversity of Central PunjabLahore-54782Pakistan Chemistry Department Faculty of Applied SciencesUmm Al-Qura UniversityMakkahSaudi Arabia

The metal complexes of norfloxacin were prepared, and their structures were characterized using spectroscopic techniques like IR, 1H NMR, UV, atomic absorption, and CHN analysis. The solubility, melting point, and conductance measurements were also performed. These studies suggested that norfloxacin formed complexes with the metals utilizing carbonyl oxygen atom of the ring and carboxylic group oxygen atom. The antibacterial activities of these metal complexes against 14 different Gram-positive and Gram-negative microorganisms were studied by the disk susceptibility method. It was observed that the complexes of norfloxacin with magnesium, calcium, cobalt, nickel, and copper showed improved activity compared with the stated drug.

关键词： Norfloxacin Metal complexes Characterization Antibacterial activities

Floristic composition and ecological gradient analyses of the Liakot Forests in the Kalam region of District Swat,Pakistan

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Journal of Forestry Research 2019年第4期30卷 1407-1416页

作者： Sohail Anwar Shujaul Mulk Khan zeeshan Ahmad Zahid Ullah Majid Iqbal Department of Plant Sciences Quaid-i-Azam UniversityIslamabad 45320Pakistan Centre for Plant Science and Biodiversity University of SwatSwat 19130Pakistan

Kalam Kohistan is a dry,temperate hilly region in the Hindu Raj Series of the Greater Hindu Kush Mountains with diverse *** plant distribution and composition is expression of a range of various environmental variables,ecological and floristic attributes of vegetation in the Laikot Forests were therefore evaluated via consecutive explorative *** forests have not been evaluated ecologically before due to harsh climatic conditions and issues of accessibility and the study in hand is one of the first in its *** ecological techniques were used to sample forest vegetation and identify species in quadrats of 2 m×2 m for herbs,5 m×5 m for shrubs and 10 m×10 m for *** the data of 195 plant species and environmental factors were analyzed via Two-way Cluster Analysis and Canonical Correspondence Analysis using PCORD and CANOCO *** 195 plant species from 63 families were 27 species of Asteraceae,the most-speciose family,followed by Poaceae(20 spp.).The dominant life form was therophyte(86 spp.;44%share),followed by phanerophyte(41 spp.;21%share).For the leaf size spectrum,most prevalent was nanophyll(73 spp.;44%)followed by microphyll(66 spp.,34%)and mesophyll(44 spp.;23%).Calcium carbonate,pH,potassium,sand,silt,organic matter,slope aspect and grazing significantly influenced species composition,distribution and *** floristic variation in the region was diverse due to elevational and aspect gradients and thus devided into three *** vegetation zonation can be utilized for forest management,species and habitat *** in situ and ex situ conservation of threatened plant species may improve their conservation status in future if address properly.

关键词： Floristic composition Ecological factors Life form spectra Leaf form classes Elevation zones Canonical correspondence analysis(CCA)