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Structure Preserving Algorithm for Fractional Order Mathematical Model of COVID-19

Computers, Materials & Continua 2022年第5期71卷 2141-2157页

作者： zafar iqbal Muhammad Aziz-ur Rehman Nauman Ahmed Ali Raza Muhammad Rafiq Ilyas Khan Kottakkaran Sooppy Nisar Department of Mathematics University of Management and TechnologyLahorePakistan Department of Mathematics and Statistics The University of LahoreLahorePakistan Stochastic Analysis&Optimization Research Group Department of MathematicsAir UniversityIslamabad44000Pakistan Department of Mathematics National College of Business Administration and EconomicsLahorePakistan Department of Mathematics Faculty of SciencesUniversity of Central PunjabLahore54500Pakistan Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh City72915Vietnam Department of Mathematics College of Arts and Science at Wadi AldawaserPrince Sattam Bin Abdulaziz UniversityAlkharj11991Kingdom of Saudi Arabia

In this article,a brief biological structure and some basic properties of COVID-19 are described.A classical integer order model is modified and converted into a fractional order model withξas order of the fractional derivative.Moreover,a valued structure preserving the numerical design,coined as Grunwald–Letnikov non-standard finite difference scheme,is developed for the fractional COVID-19 model.Taking into account the importance of the positivity and boundedness of the state variables,some productive results have been proved to ensure these essential features.Stability of the model at a corona free and a corona existing equilibrium points is investigated on the basis of Eigen values.The Routh–Hurwitz criterion is applied for the local stability analysis.An appropriate example with fitted and estimated set of parametric values is presented for the simulations.Graphical solutions are displayed for the chosen values ofξ(fractional order of the derivatives).The role of quarantined policy is also determined gradually to highlight its significance and relevancy in controlling infectious diseases.In the end,outcomes of the study are presented.

关键词： Coronavirus pandemic model deterministic ordinary differential equations numerical methods convergence analysis

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CNN Channel Attention Intrusion Detection SystemUsing NSL-KDD Dataset

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Computers, Materials & Continua 2024年第6期79卷 4319-4347页

作者： Fatma S.Alrayes Mohammed Zakariah Syed Umar Amin zafar iqbal Khan Jehad Saad Alqurni Information Systems Department College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia College of Computer and Information Sciences King Saud UniversityRiyadh11362Saudi Arabia College of Computer and Information Sciences Prince Sultan UniversityRiyadh11586Saudi Arabia Department of Educational Technologies College of EducationImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia

Intrusion detection systems(IDS)are essential in the field of cybersecurity because they protect networks from a wide range of online threats.The goal of this research is to meet the urgent need for small-footprint,highly-adaptable Network Intrusion Detection Systems(NIDS)that can identify anomalies.The NSL-KDD dataset is used in the study;it is a sizable collection comprising 43 variables with the label’s“attack”and“level.”It proposes a novel approach to intrusion detection based on the combination of channel attention and convolutional neural networks(CNN).Furthermore,this dataset makes it easier to conduct a thorough assessment of the suggested intrusion detection strategy.Furthermore,maintaining operating efficiency while improving detection accuracy is the primary goal of this work.Moreover,typical NIDS examines both risky and typical behavior using a variety of techniques.On the NSL-KDD dataset,our CNN-based approach achieves an astounding 99.728%accuracy rate when paired with channel attention.Compared to previous approaches such as ensemble learning,CNN,RBM(Boltzmann machine),ANN,hybrid auto-encoders with CNN,MCNN,and ANN,and adaptive algorithms,our solution significantly improves intrusion detection performance.Moreover,the results highlight the effectiveness of our suggested method in improving intrusion detection precision,signifying a noteworthy advancement in this field.Subsequent efforts will focus on strengthening and expanding our approach in order to counteract growing cyberthreats and adjust to changing network circumstances.

关键词： Intrusion detection system(IDS) NSL-KDD dataset deep-learning machine-learning CNN channel Attention network security

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Metal-free, carbon-based catalysts for oxygen reduction reactions

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Frontiers of Chemical Science and Engineering 2015年第3期9卷 280-294页

作者： Zhiyi Wu zafar iqbal Xianqin Wang Department of Materials Science and Engineering New Jersey Institute of Technology Newark NJ 07102 USA Department of Chemistry and Environmental Science New Jersey Institute of Technology Newark NJ 07102 USA Department of Chemical Biological and Pharmaceutical Engineering New Jersey Institute of Technology Newark NJ 07102 USA

Developing metal-free, carbon-based catalysts to replace platinum-based catalysts for oxygen reduction reactions （ORRs） is an emerging area of research. In recent years, different carbon structures including carbon doped with IIIA-VIIA heteroatoms （C-M site-based, where M represents the doped heteroatom） and polynitrogen （PN） compounds encapsulated in carbon nanotubes （CNTs）（N N site-based） have been synthesized. Compared to metallic catalysts, these materials are highly active, stable, inexpensive, and environmentally friendly. This review discusses the development of these materials, their ORR performances and the mechanisms for how the incorpora- tion of heteroatoms enhances the ORR activity. Strategies for tailoring the structures of the carbon substrates to improve ORR performance are also discussed. Future studies in this area will need to include optimizing synthetic strategies to control the type, amount and distribution of the incorporated heteroatoms, as well as better understanding the ORR mechanisms in these catalysts.

关键词： oxygen reduction reaction electrocatalysis metal-flee carbon-based polynitrogen

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Feed particle selection and nutrient intake altered by pecking stone consumption and beak length in free-range laying hens

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Animal Nutrition 2019年第2期5卷 140-147页

作者： zafar iqbal Kelly Drake Robert A.Swick Rider A.Perez-Maldonado Isabelle Ruhnke School of Environmental and Rural Science Faculty of ScienceAgricultureBusiness and LawUniversity of New EnglandArmidaleNSW2351Australia South Australian Research and Development Institute Roseworthy CampusUniversity of AdelaideSouth Australia5371Australia DSM Nutritional Products Singapore117440Singapore

The present study investigated the effects of pecking stones on feeding behaviour of hens from 16 to 46 weeks of age. Eighteen flocks of Hy-Line Brown hens were housed in 2 commercial free-range housing systems. Farm A housed 10 flocks of beak trimmed(infrared beak treatment) hens in fixed sheds. Farm B housed 8 flocks of hens with intact beaks in mobile sheds. On each farm, flocks were equally assigned to control groups(no access to pecking stones) and treatment groups(access to pecking stones). Data were evaluated every 10 weeks. At each time point, 10 hens per flock were housed in individual pens, and each hen was provided with 250 g of mash diet and ad libitum water for 24 h. After 24 h, feed samples were collected and used to determine 24-h feed intake. Nutrient and particle selection was measured by subtracting nutrients and particles present in the leftover feed from the vaules obtained in the offered feed and expressed the change(A). In addition, pecking stone consumption was recorded for each flock.Data were analysed separately for each farm using fixed effects of pecking stone availability and hen age.Spearman’s rho correlation coefficients and linear regression models were constructed to evaluate the relationship of beak length and pecking stone usage, discrete mean particle size(dMEAN) consumption(△ dMEAN), and △ nutrient intake. Hens with access to pecking stones consumed significantly lower quantities of large feed particles(>2.8 mm) on farm A(P = 0.029) and selected significantly more fine particles, on farm B(P = 0.013). Overall, positive relationships(P = 0.001) between beak length and pecking stone consumption, A dMEAN, and A phosphorus consumption were observed. In conclusion,pecking stone consumption resulted in reduced selection and consumption of feed particles in hens housed on both farms. Further research is warranted to investigate the effect of pecking stones on sensory innervation of the beak.

关键词： Poultry Welfare Feeding behaviour Nutrition Environmental enrichment

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A Structure Preserving Numerical Method for Solution of Stochastic Epidemic Model of Smoking Dynamics

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Computers, Materials & Continua 2020年第10期65卷 263-278页

作者： Ali Raza Muhammad Rafiq Nauman Ahmed Ilyas Khan Kottakkaran Sooppy Nisar zafar iqbal Department of Mathematics National College of Business Administration and EconomicsLahorePakistan Faculty of Engineering University of Central PunjabLahorePakistan Department of Mathematics and Statistics The University of LahoreLahorePakistan Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh CityVietnam Department of Mathematics College of Arts and Science at Wadi AldawaserPrince Sattam Bin Abdulaziz UniversityAlkharjSaudi Arabia

In this manuscript,we consider a stochastic smoking epidemic model from behavioural sciences.Also,we develop a structure preserving numerical method to describe the dynamics of stochastic smoking epidemic model in a human population.The structural properties of a physical system include positivity,boundedness and dynamical consistency.These properties play a vital role in non-linear dynamics.The solution for nonlinear stochastic models necessitates the conservation of these properties.Unfortunately,the aforementioned properties of the model have not been restored in the existing stochastic methods.Therefore,it is essential to construct a structure preserving numerical method for a reliable analysis of stochastic smoking model.The usual explicit stochastic numerical methods are time-dependent and violate most of the structural properties.In this work,we have developed the implicitly driven explicit method for the solution of stochastic smoking model.It is also proved that the newly developed method sustains all the aforementioned properties of the system.Finally,the convergence analysis of the newly developed method and graphical illustrations are presented.

关键词： Smoking model stochastic numerical techniques convergence

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Vibration characteristics of FGM circular cylindrical shells filled with fluid using wave propagation approach

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Applied Mathematics and Mechanics(English Edition) 2009年第11期30卷 1393-1404页

作者： zafar iqbal Muhammad Nawaz Naeem Nazra Sultana Shahid Hussain Arshad Abdul Ghafar Shah Department of Mathematics University of Sargodha Department of Mathematics G. C. University Faisalabad Department of Mathematics University of Sargodha Department of Mathematics The Islamia University of Bahawalpur

The vibration characteristics of a functionally graded material circular cylindrical shell filled with fluid are examined with a wave propagation approach. The shell is filled with an incompressible non-viscous fluid. Axial modal dependence is approximated by exponential functions. A theoretical study of shell vibration frequencies is analyzed for simply supported-simply supported, clamped-simply supported, and clamped-clamped boundary conditions with the fluid effect. The validity and the accuracy of the present method are confirmed by comparing the present results with those available in the literature. Good agreement is observed between the two sets of results.

关键词： functionally graded material Love＇s shell theory cylindrical shell volumefraction law natural frequency wave propagation

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Numerical Analysis of Novel Coronavirus (2019-nCov) Pandemic Model with Advection

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Computers, Materials & Continua 2021年第6期67卷 2933-2953页

作者： Shumaila Azam Nauman Ahmed Ali Raza Muhammad Sajid iqbal Muhammad Rafiq Ilyas Khan Kottakkaran Sooppy Nisar Muhammad Ozair Ahmad zafar iqbal Department of Mathematics and Statistics The University of LahoreLahorePakistan Department of Mathematics National College of Business Administration and Economics LahorePakistan Faculty of Engineering University of Central Punjab Lahore Pakistan Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh City72915Vietnam Department of Mathematics College of Arts and Science at Wadi AldawaserPrince Sattam Bin Abdulaziz University11991AlkharjKingdom of Saudi Arabia Department of Mathematics University of Management and TechnologyLahorePakistan

Recently,the world is facing the terror of the novel corona-virus,termed as COVID-19.Various health institutes and researchers are continuously striving to control this pandemic.In this article,the SEIAR(susceptible,exposed,infected,symptomatically infected,asymptomatically infected and recovered)infection model of COVID-19 with a constant rate of advection is studied for the disease propagation.A simple model of the disease is extended to an advection model by accommodating the advection process and some appropriate parameters in the system.The continuous model is transposed into a discrete numerical model by discretizing the domains,finitely.To analyze the disease dynamics,a structure preserving non-standard finite difference scheme is designed.Two steady states of the continuous system are described i.e.,virus free steady state and virus existing steady state.Graphical results show that both the steady states of the numerical design coincide with the fixed points of the continuous SEIAR model.Positivity of the state variables is ensured by applying the M-matrix theory.A result for the positivity property is established.For the proposed numerical design,two different types of the stability are investigated.Nonlinear stability and linear stability for the projected scheme is examined by applying some standard results.Von Neuman stability test is applied to ensure linear stability.The reproductive number is described and its pivotal role in stability analysis is also discussed.Consistency and convergence of the numerical model is also studied.Numerical graphs are presented via computer simulations to prove the worth and efficiency of the quarantine factor is explored graphically,which is helpful in controlling the disease dynamics.In the end,the conclusion of the study is also rendered.

关键词： 2019-nCov infectious model with advection reproductive number stability analysis numerical graphs

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Impact of on-range choice feeding with black soldier fly larvae(Hermetia illucens)on flock performance,egg quality,and range use of free-range laying hens

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Animal Nutrition 2018年第4期4卷 452-460页

作者： Isabelle Ruhnke Camille Normant Dana L.M.Campbell zafar iqbal Caroline Lee Geoff N.Hinch Julie Roberts Faculty of Science AgricultureBusiness and LawSchool of Environmental and Rural ScienceUniversity of New EnglandArmidaleNSW 2351Australia Institut Polytechnique LaSalle Beauvais 60000 BeauvaisFrance F.D.McMaster Laboratory Commonwealth Scientific and Industrial Research Organisation(CSIRO)ArmidaleNSW 2350Australia

Semi-intensive free-range farm systems are common in Australia, and these systems frequently practise on-range feeding. The objective of this study was to investigate the benefit of on-range choice feeding on flock performance, egg quality, and range use of free-range laying hens using black soldier fly larvae(Hermetia illucens, BSF). A total of 160 mature ISA brown laying hens, previously determined to range daily, were allocated to a control group(control) or a treatment group(BSF) with various replicates depending on the parameter investigated. All hens were fed ad libitum indoors with a wheat-soy based diet formulated according to breed requirements. Black soldier fly hens were offered dried BSF larvae ad libitum on the range. Body weight, feed intake, BSF intake, egg production, feed conversion ratio, internal and external egg quality parameters, and individual range use using radio-frequency identification(RFID)technology was evaluated. Black soldier fly hens consumed on average 15 ± 1.7 g BSF larvae/hen per day.There were no differences between BSF and control hens for any of the performance parameters obtained(P > 0.05). Egg weight, shell weight, and shell thickness of eggs from BSF hens were significantly lower(P = 0.003, P = 0.001, and P = 0.004, respectively) than those of eggs from control hens. Egg yolk colour was significantly paler in eggs from BSF hens(P 0.05) except for BSF hens showing longer total maximum time for a single visit to the range(P = 0.011). In conclusion, the average intake of BSF larvae indicated a good level of acceptance. Feed formulation should be adjusted for the intake of the choice fed source. The impact of choice-feeding on range use was minor.

关键词： Behaviour Chicken Insect protein Nutrition Poultry Radio-frequency identification

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新型Al/CuFe多层核壳颗粒增强铝基复合材料的显微组织和力学性能

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Transactions of Nonferrous Metals Society of China 2022年第6期32卷 1822-1833页

作者： Rashid ALI Fahad ALI Aqib ZAHOOR Rub Nawaz SHAHID Naeem ul Haq TARIQ zafar iqbal Adnan Qayyum BUTT Saad ULLAH Hasan Bin AWAIS Department of Metallurgy and Materials Engineering Pakistan Institute of Engineering and Applied Sciences(PIEAS)IslamabadPakistan Materials Division Pakistan Institute of Nuclear Science and Technology(PINSTECH)IslamabadPakistan

采用不同烧结工艺制备新型Al/Cu Fe多层核壳颗粒增强铝基复合材料(AMCs),研究其对显微组织和力学性能的影响。分别采用电置换法和化学镀法在铝粉颗粒上沉积Cu层和Fe层,制备多层Al/Cu Fe核壳颗粒。采用X射线衍射(XRD)、扫描电子显微镜(SE... 详细信息

采用不同烧结工艺制备新型Al/Cu Fe多层核壳颗粒增强铝基复合材料(AMCs),研究其对显微组织和力学性能的影响。分别采用电置换法和化学镀法在铝粉颗粒上沉积Cu层和Fe层,制备多层Al/Cu Fe核壳颗粒。采用X射线衍射(XRD)、扫描电子显微镜(SEM)/能谱(EDX)、密度计、显微硬度和压缩试验等方法对复合材料进行表征。结果表明,在放电等离子烧结复合材料中,由于沉积层向金属间化合物相转变,界面反应程度提高,复合材料的相对密度(99.26%)、显微硬度(165 HV0.3)和强度(572 MPa)均显著提高。此外,热压复合材料壳层结构中存在的未转化Cu导致其断裂应变最高(20.4%)。研究结果对通过选择合适的烧结路径来调整AMCs的显微组织和控制其力学性能具有重要意义。

关键词：核壳增强相铝基复合材料化学镀烧结工艺放电等离子烧结界面反应

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枸杞功效成分衍生物AA-3βG的合成及其反应分子机理

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宁夏农林科技 2022年第4期63卷 15-18,75页

作者：何丽丽孙健纪静雯翟丽娟 zafar iqbal 宁夏农林科学院农业资源与环境研究所宁夏银川750002

鉴于枸杞在分子层面高附加值产品研发严重滞后之局面,本文通过深度分析反应分子机理,以一种廉价易得的维生素C作为起始原料,经4步反应有效地合成枸杞功效物质AA-2βG的衍生物3-O-β-D-葡萄糖基copyranosyl-L-抗坏血酸(AA-3βG),为枸杞... 详细信息

鉴于枸杞在分子层面高附加值产品研发严重滞后之局面,本文通过深度分析反应分子机理,以一种廉价易得的维生素C作为起始原料,经4步反应有效地合成枸杞功效物质AA-2βG的衍生物3-O-β-D-葡萄糖基copyranosyl-L-抗坏血酸(AA-3βG),为枸杞功效物质基础研究和高端产品研发提供了技术支撑。

关键词：枸杞功效成分衍生物 AA-3βG

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