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A reliable numerical analysis for stochastic gonorrhea epidemic model with treatment effect

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International Journal of Biomathematics 2019年第6期12卷 221-246页

作者： Ali Raza Muhammad Shoaib arif Muhammad Ualiq Department of Mathematics Stochastic Analysis and Optimization Research Group Air University PAF Complex E-9 Islamabad 44000PedralPakistan Faculty of Engineering.University of Central PunjabLahore 54000 PunjabPakistan

The phenomena of disease spread are unpredictable in nature due to random mixing of individuals in a *** is of more significance to include this randomness while modeling infectious *** epidemics including tlieir stochastic behavior could be a more realistic approach in many *** thus paper,a stochastic gon orrhea epidemic model with treatment effect has been analyzed *** solution of stochastic model is presented in comparison with its deterministic *** dynamics of the gonorrhea disease is governed by a threshold quantity Ai called basic reproductive ***.A11 shows the persistence of disease in *** standard numerical schemes like Euler *** Euler and stochastic Rurige Kutta are highly dependent on step size and do not behave well in certain scenarios.A competitive non-standard finite dif ference numerical scheme in stochastic setting is proposed,which is independent of step size and remains consistent with the corresponding deterministic model.

关键词： Gonorrhea disease stochastic differential equations stochastic numerical schemes

Correlation between electrical conductivity–optical band gap energy and precursor molarities ultrasonic spray deposition of ZnO thin films

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Journal of Semiconductors 2013年第11期34卷 15-19页

作者： Said Benramache Okba Belahssen Abderrazak Guettaf Ali arif Material Sciences Laboratory Faculty of Science University of Biskra Physic Laboratory of Thin Films and Applications LPCMA University of Biskra Department of Electrical Faculty of Technology University of Biskra

ZnO thin films were deposited using the simple, flexible and cost-effective spray ultrasonic technique at different precursor molarities values. The films were deposited on a glass substrate at 350℃. This paper is to present a new approach to the description of correlation between electrical conductivity and optical gap energy with precursor molarity of ZnO thin films. The ZnO films exhibit higher electrical n-type semiconductors, whose band gap energy increased from 3.08 to 3.37 eV with an increasing of precursor molarity of 0.05 to 0.1 M. The maximum value of electrical conductivity of the films is 7.96 （***）-1 obtained in the ZnO thin film for precursor molarity 0.125 M. The correlation between the electrical and the optical properties with the precursor molarity suggests that the electrical conductivity of the films is predominantly influenced by the band gap energy and the precursor molarity. The measurement of the electrical conductivity of the films with correlation is equal to the experimental with the error is about 1% in the higher conductivity.

关键词： ZnO thin films correlation electrical conductivity, ultrasonic spray technique

Bio-inspired optimization algorithms for optical parameter extraction of dielectric materials: A comparative study

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Chinese Physics B 2016年第10期25卷 202-208页

作者： Md Ghulam Saber Kh arif Shahriar Ashik Ahmed Rakibul Hasan Sagor Department of Electrical and Electronic Engineering Islamic University of Technology (IUT) Department of Electrical and Electronic Engineering Northern University Bangladesh (NUB)

Particle swarm optimization(PSO) and invasive weed optimization(IWO) algorithms are used for extracting the modeling parameters of materials useful for optics and photonics research community. These two bio-inspired algorithms are used here for the first time in this particular field to the best of our knowledge. The algorithms are used for modeling graphene oxide and the performances of the two are compared. Two objective functions are used for different boundary values. Root mean square(RMS) deviation is determined and compared.

关键词： optical parameter extraction particle swarm optimization invasive weed optimization graphene oxide optimization

Mass Transfer of MHD Nanofluid in Presence of Chemical Reaction on A Permeable Rotating Disk with Convective Boundaries, Using Buongiorno’s Model

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Computer Modeling in Engineering & Sciences 2018年第7期116卷 31-49页

作者： Muhammad Shoaib arif Yasir Nawaz Mairaj Bibi Zafar Ali Department of Mathematics Air UniversityPAF Complex E-9Islamabad44000Pakistan Department of Mathematics Comsats UniversityPark Road Chak Shahzad CampusIslamabad44000Pakistan

This communiquéis opted to study the flow of nanofluid because of heated disk rotation subjected to the convective boundaries with chemical reaction of first *** Buongiorno’s model for nanofluids is used due to its wide range of applications and the rotating disk under investigation is *** magneto Reynolds parameter and boundary layer assumptions are carried out to formulate the *** system of nonlinear partial differential equations governing the flow problem is converted into the set of ordinary differential equations by using particular relations known as Von Karman *** complicated set of coupled ordinary differential equations with complicated boundary conditions is set to solve by an analytical technique Homotopy Analysis Method(HAM).Whereby the results obtained by the aforementioned method are provided analytically and analyzed *** validation of the work is confirmed by providing comparison of previous works in tabular *** of chemical reaction parameter on mass transfer rate is also highlighted tabularly for its *** and Sherwood numbers calculated and compared to the like literature and found in good agreement.

关键词： Chemical reaction rotating disk nanoparticles velocity slip magnetic effect.

Spatio-temporal dynamics of cyanobacterial abundance and toxicity in a Mediterranean hypereutrophic lake

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海洋湖沼学报(英文) 2023年第5期41卷 1834-1848页

作者： Salah arif Nawel DJEBBARI Saber BELHAOUES Hassen TOUATI Mourad BENSOUILAH Eco-biology Laboratory for Marine Environments and Coastal Areas Faculty of SciencesMarine Sciences DepartmentUniversity of Badji MokhtarAnnaba 23000Algeria

The Mediterranean basin is considered one of the most vulnerable areas in the world under the impacts of global warming and changes in precipitation ***,a shallow and polymictic freshwater lake located in northeastern Algeria(36°50′N,08°23′E),has recently experienced a significant proliferation of harmful cyanobacteria resulting in the generation of *** carried out this study in order to understand the succession patterns of dominant cyanobacteria and cyanotoxin production and the factors driving this in Oubeira Lake.A total of 26 cyanobacterial genera were identified,and among them Microcystis and Planktothrix accounted for more than 60%of the overall cell *** summer/fall period was dominated by Microcystis,Planktothrix,and in lesser extend by Cylindrospermum,*** the fall/winter transition,Dolichospermum,Pseudanabaena,and Aphanizomenon were the dominant ***,the bloom-forming cyanobacteria showed significant differences between months but not between *** microcystins(MC-LR)was detected in all collected samples(0.62-and 19.14-μg MC-LR equivalent/L),but appeared in high concentrations throughout the period of dominance of Microcystis and *** was more sensitive to nutrients than to *** was more dependent on temperature than on nutrients,which explains their coexistence during summer-fall ***,both genera are positively correlated with MC-LR and would probably be the main producers of ***,Dolichospermum,and Aphanizomenon co-occurred at the end of Planktothrix dominance period(December).Aphanizomenon and Pseudanabaena were correlated negatively with temperature and positively with water *** showed a strong positive correlation with *** Lake,could serve as a model of how cyanobacteria blooms may develop in lakes within Mediterranean climates.

关键词： Oubeira Lake cyanobacteria microcystin spatiotemporal variations shallow hypereutrophic lake

Effects of transpiration on unsteady MHD flow of an upper convected Maxwell (UCM) fluid passing through a stretching surface in the presence of a first order chemical reaction

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Chinese Physics B 2013年第12期22卷 315-322页

作者： Swati Mukhopadhyay M.Golam arif M.Wazed Ali Pk Department of Mathematics The University of Burdwan Institute of Business Administration University of Rajshahi Department of Mathematics University of Rajshahi

The aim of this article is to present the effects of transpiration on the unsteady two-dimensional boundary layer flow of non-Newtonian fluid passing through a stretching sheet in the presence of a first order constructive/destructive chemical reaction. The upper-convected Maxwell （UCM） model is used here to characterize the non-Newtonian behavior of the fluid. Using similarity solutions, the governing nonlinear partial differential equations are transformed into ordinary ones and are then solved numerically by the shooting method. The flow fields and mass transfer are significantly influenced by the governing parameters. The fluid velocity initially decreases as the unsteadiness parameter increases and the concentration decreases significantly due to the increase in the unsteadiness. The effect of increasing values of transpiration （suction） and the Maxwell parameter is to suppress the velocity field; however, the concentration is enhanced as transpiration （suction） and the Maxwell parameter increase. Also, it is found that the fluid velocity decreases as the magnetic parameter increases; however, the concentration increases in this case.

关键词： unsteady flow MHD upper convected Maxwell fluid stretching surface transpiration chemical reaction

Impact of land cover change on land surface temperature: A case study of Spiti Valley

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Journal of Mountain Science 2018年第8期15卷 1658-1670页

作者： KUMAR Pankaj HUSAIN arif SINGH Ram Babu KUMAR Manish Department of Geography Delhi School of Economics University of Delhi Department of Geography Kalindi College University of Delhi

Land surface temperature(LST) is the skin temperature of the earth surface. LST depends on the amount of sunlight received by any geographical area. Apart from sun light, LST is also affected by the land cover, which leads to change in land surface temperature. Impact of land cover change(LCC) on LST has been assessed using Landsat TM5, Landsat 8 TIRS/OLI and Digital Elevation Model(ASTER) for Spiti Valley, Himachal Pradesh, India. In the present study, Spiti valley was divided into three altitudinal zones to check the pattern of changing land cover along different altitudes and LST was calculated for all the four land cover categories extracted from remote sensing data for the years of 1990 and 2015. Matrix table was used as a technique to evaluate the land cover change between two different years. Matrix table shows that as a whole, about 2,151,647 ha(30%) area of Spiti valley experienced change in land cover in the last 25 years. The result also shows vegetation and water bodies increased by 107,560.2 ha(605.87%) and 45 ha(0.98%), respectively. Snow cover and barren land decreased by 19,016.5 ha(23.92%) and 88,589(14.14%), during the study period. A significant increase has been noticed in vegetation amongst all land cover types. Minimum, maximum and mean LST for three altitudinal zones have been calculated. The mean LST recorded was 11℃ in 1990 but it rose by 2℃ and reached to 13℃ in 2015. Changes in LST were obtained for each land cover categories. The mean temperature of different land cover types was calculated by averaging value of all pixels of a given land cover types. The mean LST of vegetation, barren land, snow cover and water body increased by 6℃, 9℃, 1℃, and 7℃, respectively. Further, relationships between LST, Normalized Difference Snow Index(NDSI), and Normalised Difference Vegetation Index(NDVI) were established using Linear Regression.

关键词： Land surface temperature Land cover change Normalised difference snow index Normalised Difference Vegetation Index DEM Remote Sensing GIS Linear Regression

Professor Hu Zhihong:The New President of the Society for Invertebrate Pathology

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Virologica Sinica 2018年第5期33卷 383-384页

作者： Basil arif Jiali Si Zheng-Li Shi Scientist Emeritus Laboratory for Molecular VirologyGLFC Wuhan Institute of Virology Chinese Academy of Sciences

The Society for Invertebrate Pathology (SIP)is foremost in the world covering all aspects of related research in insect virology,bacteriology,mycology,parasitology and microbial *** SIP has a wide scientific appeal with members from many countries spanning every continent in the *** of members to the Society's Governing Council is based on scientific standing,contributions, reputation and involvement in the activities of the Society.

关键词： Professor Hu Zhihong:The New President of the Society for Invertebrate Pathology

The China Pakistan Economic Corridor——Challenges and Policies Implications

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The China Pakistan Economic Corridor——Challenges and Polic...

作者： Muhammad arif 西南大学

学位级别：硕士

The China-Pakistan Economic Corridor（CPEC）-the latest venture in a history of bilateral economic cooperation,with a $46 billion investment in energy and infrastructure development in Pakistan-is considered a game changer for Pakistan’s *** a flagship project of China’s One Belt One Road initiative,the corridor will connect Kashgar in Western China with the port of Gwadar in Pakistan on the Arabian Sea,serving as a gateway to the Middle East,Africa,and Central *** CPEC,in addition to boosting Pakistan’s economy and meeting China’s energy needs and development of its western region,is likely to bring stability in the region through economic ***,a project of such scale certainly faces equally significant *** thesis examines obstacles that have the potential to affect the implementation of the project,including the unstable situation in Afghanistan,competing interests of immediate neighbors like India and Iran,especially India’s suspicions,and *** about the *** thesis draws from a wide range of scholarly and peer-reviewed literature,academic journals,think-tank reports,and government-sponsored *** from their analysis,though,is the consideration of the regional geopolitical dynamics and Pakistan’s domestic challenges?particularly insecurity and violence?that can affect the implementation of the CPEC *** thesis seeks to address that gap and provides policy recommendations for Pakistan to deal with potential impediments in implementation of the project.

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