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Frontiers of Information Technology & Electronic Engineering 2018年第2期19卷 246-259页

作者： Muhammad Asif Zahoor RAJA Muhammad Saeed ASLAM naveed Ishtiaq CHAUDHARY Wasim ullah KHAN Department of Electrical Engineering COMSATS Institute of Information TechnologyAttock Campus Pakistan Institute of Engineering and Applied Sciences Department of Electronic Engineering International Islamic University

In this study, hybrid computational frameworks are developed for active noise control（ANC） systems using an evolutionary computing technique based on genetic algorithms（GAs） and interior-point method（IPM）, following an integrated approach, GA-IPM. Standard ANC systems are usually implemented with the filtered extended least mean square algorithm for optimization of coefficients for the linear finite-impulse response filter, but are likely to become trapped in local minima（LM）. This issue is addressed with the proposed GA-IPM computing approach which is considerably less prone to the LM problem. Also, there is no requirement to identify a secondary path for the ANC system used in the scheme. The design method is evaluated using an ANC model of a headset with sinusoidal, random, and complex random noise interferences under several scenarios based on linear and nonlinear primary and secondary paths. The accuracy and convergence of the proposed scheme are validated based on the results of statistical analysis of a large number of independent runs of the algorithm.

关键词： Active noise control (ANC) Filtered extended least mean square (FXLMS) Memetic computing Genetic algorithms Interior-point method

Numerical Solution of Casson Fluid Flow under Viscous Dissipation and Radiation Phenomenon

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Journal of Applied Mathematics and Physics 2022年第2期10卷 475-490页

作者： naveed Akbar Sardar Muhammad Hussain Riaz ullah Khan School of Mathematics and Statistics Sichuan University of Science and Engineering Yibin China Department of Mathematical Sciences Balochistan University of Information Technology Engineering and Management Sciences (BUITEMS) Quetta Pakistan School of Life Science and Engineering University of Electronic Science and Technology of China Chengdu China

This article numerically investigates the 2D, steady, laminar, incompressible fluid flow, mass and heat transfer of a non-Newtonian fluid model induced by stretching surface. A Casson fluid model is considered to study the non-Newtonian behavior of the flowing fluid. The magnetic field and a porous medium are considered in the flow momentum, whereas the viscous dissipation is also taken into account in the energy transport phenomena. To see the fluid concentration, the concentration equation is used. Furthermore, the Nusselt number coefficient and skin friction are modified with the addition of nonlinear stretching and radiation parameters. With the similarity transformation, the nonlinear governing partial differential equations are transformed into a system of ordinary differential equations and then numerically solved using a fourth-order Runge-Kutta scheme with the shooting method. The relevant parameters of interest are interpreted for graphical results. The results illustrate that the fluid energy increases effectively with an increase in the Eckert number, radiation parameter, and heat source parameter, while it decreases by increasing the Prandtl number and heat sink parameter. Both the wall skin friction and the wall Nusselt number coefficient decelerate with an increase in the Casson parameter.

关键词： Casson Fluid Porous Medium Runge-Kutta Scheme Shooting Method Prandtl Number Nusselt Number Coefficient

Postnatal feeding with high-fat diet induces obesity and precocious puberty in C57BL/6J mouse pups： a novel model of obesity and puberty

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Frontiers of Medicine 2017年第2期11卷 266-276页

作者： Rahim ullah Yan Su Yi Shen Chunlu Li Xiaoqin Xu Jianwei Zhang Ke Huang naveed Rauf Yang He Jingjing Cheng Huaping Qin Yu-Dong Zhou Junfen Fu Department of Endocrinology Children's Hospital Zhejiang University School of Medicine Hangzhou 310051 China Department of Neurobiology Institute of Neuroscience and the Collaborative Innovation Center for Brain Science Key Laboratory of Medical Neurobiology of the Ministry of Health of China Zhejiang University School of Medicine Hangzhou 310058 China

Childhood obesity and obesity-related metabolic complications are induced by a high-fat postnatal diet. The lack of a suitable animal model, however, remains a considerable challenge in obesity studies. In the current study, we provided high-fat diet （HFD） to dams during lactation and to pups after weaning. We also developed a novel model of C57BL/6J mouse pups with HFD-induced postnatal obesity. Results showed that feeding with HFD induces fat deposition and obesity in pups. Furthermore, HFD more potently increased the body weight （BW） of male than female pups. HFD-fed female pups were obese, underwent precocious puberty, and showed increased kisspeptin expression in the hypothalamus. However, parental obesity and precocious puberty exerted no synergistic effects on the HFD-induced postnatal weight gain and puberty onset of the pups. Interestingly, some HFD-fed litters with normal BW also exhibited precocious puberty. This finding suggested that diet composition but not BW triggers puberty onset. Our model suggests good construction validity of obesity and precocious puberty. Furthermore, our model can also be used to explore the mutual interactions between diet-induced postnatal childhood obesity and puberty.

关键词： postnatal HFD feeding obesity kisspeptin HPG axis precocious puberty

Electro-derived Cu-Cu2O nanocluster from LDH for stable and selective C2 hydrocarbons production from CO2 electrochemical reduction

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Journal of Energy Chemistry 2020年第9期29卷 169-180,I0005页

作者： naveed Altaf Shuyu Liang Liang Huang Qiang Wang College of Environmental Science and Engineering Beijing Forestry UniversityBeijing 100083China

Recently,CO2 conversion by electrochemical tool into value-added chemicals has been considered as one of the most promising strategies to offer sustainable development in energy and *** this contribution,we investigated electro-derived composites from Cu-based layered double hydroxide(LDH)for CO2 electrochemical *** Cu-Cu2O based nanocomposite(HPR-LDH)were derived by using electro-strategy from LDH having the stability up to 20 h and selectivity toward C2H4 with faraday efficiency up to 36%by significantly suppressing CH4 and H2 with respect to bulk Cu foil.A highly negative reduction potential derived catalyst(HPR-LDH)maintained long-term stability for the selective production of ethylene over methane,and a small amount of Cu2O was still observed on the catalyst surface after CO2 reduction reaction(CO2RR).Moreover,such unique strategy for electro-derived composite from LDH having small nanoparticles stacked each other grown on layered structure,would provide new insight to improve durability of O-Cu combination catalysts for C-C coupling products during electrochemical CO2conversion by suppressing *** XRD,SEM,ESR,and XPS analyses confirmed that the long-term ethylene selectivity of HPR-LDH is due to the presence of subsurface *** designed composite catalyst significantly enhances the stability and selectivity,and also decreases the over potential for CO2 *** predict that the new designed LDH 2D-derived composites may attract new insight for transition metal and may open up a new direction for known structural properties of selective catalyst synthesis regarding effective CO2 reduction reaction.

关键词： Electrochemical Electro-derived strategy Layered double hydroxide Ethylene Cu2O nanocomposites

Flow of Eyring-Powell liquid due to oscillatory stretchable curved sheet with modified Fourier and Fick’s model

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Applied Mathematics and Mechanics(English Edition) 2021年第10期42卷 1461-1478页

作者： M.IMRAN Z.ABBAS M.naveed Department of Mathematics The Islamia University of BahawalpurBahawalpur 63100Pakistan Department of Mathematics Khwaja Fareed University of Engineering&Information TechnologyRahim Yar Khan 64200Pakistan

This study deals with the features of the mass and heat transport mechanism by adopting a modified version of Fourier and Fick’s model known as the CattaneoChristov double diffusive *** time-dependent magnetohydrodynamic(MHD)flow of the Eyring-Powell liquid across an oscillatory stretchable curved sheet in the presence of Fourier and Fick’s model is *** acquired set of flow equations is transformed into the form of nonlinear partial differential equations(PDEs)by applying appropriate similarity variables.A convergent series solution to the developed nonlinear equations is accomplished with the help of an analytical approach,i.e.,the homotopy analysis method(HAM).The consequences of diverse parameters,including the dimensionless EyringPowell liquid parameter,the radius of curvature,the Schmidt/Prandtl numbers,the ratio of the oscillatory frequency of the sheet to its stretchable rate constant,the mass and thermal relaxation variables involved in the flow,and the heat and mass properties,are displayed through graphs and *** is noted from this study that the amplitude of the pressure distribution rises for the high parametric values of the Eyring-Powell parameter.

关键词： oscillatory stretchable curved surface magnetohydrodynamic(MHD) Eyring-Powell liquid Cattaneo-Christov double diffusion analytical technique

Development of multi-physics numerical simulation model to investigate thermo-mechanical fatigue crack propagation in an autofrettaged gun barrel

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Defence Technology（防务技术） 2021年第5期17卷 1579-1591页

作者： naveed Hussain Faisal Qayyum Riffat Asim Pasha Masood Shah Department of Mechanical Engineering University of Engineering and TechnologyTaxilaPakistan Institut für Metallformung Technische Universitat BeragakademieFreibergGermany

In this research,a detailed multi-physics study has been carried out by numerically simulating a solid fractured gun barrel for 20 thermo-mechanical *** numerical model is based on thermal effects,mechanical stress fields and fatigue crack ***-plastic material data of modified AISI 4340 at temperatures ranging from 25 to 1200℃and at strain rates of 4,16,32 and 48 s^(-1) was acquired from high-temperature compression *** was used as material property data in the simulation *** boundary conditions applied are kept similar to the working gun barrel during continuous firing.A methodology has been provided to define thermo-mechanically active surface-to-surface type interface between the crack faces for a better approximation of stresses at the crack *** of results from non-autofrettaged and autofrettaged simulation models provide useful information about the evolution of strains and stresses in the barrel at different points under combined thermo-mechanical loading cycles in both *** effect of thermal fatigue under already induced compressive yield due to autofrettage and the progressive degradation of the accumulated stresses due to thermo-mechanical cyclic loads on the internal surface of the gun barrel(mimicking the continuous firing scenario)has been *** between energy release rate at tips of varying crack lengths due to cyclic thermo-mechanical loading in the non-autofrettaged and autofrettaged gun has been carried out.

关键词： Steel Autofrettage Gun barrel Crack propagation Thermo-mechanical fatigue Numerical simulation Residual stress dissipation

Text Encryption Using Pell Sequence and Elliptic Curves with Provable Security

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Computers, Materials & Continua 2022年第6期71卷 4971-4988页

作者： Sumaira Azhar naveed Ahmed Azam Umar Hayat Department of Mathematics Quaid-i-Azam UniversityIslamabad45320Pakistan Department of Applied Mathematics and Physics Graduate School of InformaticsKyoto UniversityKyoto606-8501Japan

The demand for data security schemes has increased with the significant advancement in the field of computation and communication *** propose a novel three-step text encryption scheme that has provable security against computation attacks such as key attack and statistical *** proposed scheme is based on the Pell sequence and elliptic curves,where at the first step the plain text is diffused to get a meaningless plain text by applying a cyclic shift on the symbol *** the second step,we hide the elements of the diffused plain text from the *** this purpose,we use the Pell sequence,a weight function,and a binary sequence to encode each element of the diffused plain text into real *** encoded diffused plain text is then confused by generating permutations over elliptic curves in the third *** show that the proposed scheme has provable security against key sensitivity attack and statistical ***,the proposed scheme is secure against key spacing attack,ciphertext only attack,and known-plaintext *** to some of the existing text encryption schemes,the proposed scheme is highly secure against modern cryptanalysis.

关键词： Text encryption pell numbers elliptic curves key sensitivity statistical cryptanalysis

Survey on Video Security:Examining Threats,Challenges,and Future Trends

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Computers, Materials & Continua 2024年第9期80卷 3591-3635页

作者： Ali Asghar Amna Shifa Mamoona naveed Asghar Department of Artificial Intelligence Faculty of ComputingThe Islamia University of BahawalpurBahawalpur63100Pakistan School of Computer Science College of Science and EngineeringUniversity of GalwayGalwayH91 TK33Ireland

Videos represent the most prevailing form of digital media for communication,information dissemination,and ***,theirwidespread use has increased the risks of unauthorised access andmanipulation,posing significant *** response,various protection approaches have been developed to secure,authenticate,and ensure the integrity of digital *** study provides a comprehensive survey of the challenges associated with maintaining the confidentiality,integrity,and availability of video content,and examining how it can be *** then investigates current developments in the field of video security by exploring two critical research ***,it examine the techniques used by adversaries to compromise video data and evaluate their *** these attack methodologies is crucial for developing effective defense ***,it explores the various security approaches that can be employed to protect video data,enhancing its transparency,integrity,and *** compares the effectiveness of these approaches across different use cases,including surveillance,video on demand(VoD),and medical videos related to disease ***,it identifies potential research opportunities to enhance video data protection in response to the evolving threat *** this investigation,this study aims to contribute to the ongoing efforts in securing video data,providing insights that are vital for researchers,practitioners,and policymakers dedicated to enhancing the safety and reliability of video content in our digital world.

关键词： Attacks threats security services video manipulation video security

Study on the synthesis of spin labeled poly(styrene-co-maleic acid)s and their segmental motion

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Magnetic Resonance Letters 2022年第2期2卷 80-90,I0002页

作者： Kaleem-Ur-Rahman naveed Li Wang Haojie Yu Qian Zhang Wei Xiong Raja Summe ullah Ahsan Nazir Muhammad Usman Shah Fahad Amin Khan Md Alim Uddin Di Shen State Key Laboratory of Chemical Engineering College of Chemical&Biological EngineeringZhejiang UniversityHangzhou310027China The First Affiliated Hospital College of MedicineZhejiang UniversityHangzhou310003China

Study of the segmental mobility of polymer chains is important when the polymer is used as drag reduction agents of crude *** spin resonance(ESR)spectroscopy can provide important information about segmental dynamics of polymer chains,which is related to their *** this article,we employed an amphiphilic polymer to study the effect of hydrophilic/hydrophobic balance of the polymers on the segmental motion of polymer ***(styrene-co-maleic acid)(PSMA)was spin labeled with 4-amino TEMPO radicals by increasing the concentration of radical moiety on the polymer *** PSMA and spin labeled-PSMAs(SL-PSMAs)were characterized by nuclear magnetic resonance(NMR),Fourier transform infrared(FT-IR)spectroscopy,Cyclic voltammetry(CV)and ESR ***-polymer complexes(IPCs)of SL-PSMA-2 were prepared by employing polyethylene glycols(PEGs)of varying molecular *** results showed that the increased hydrophobic interactions of nitroxide radicals on the SLPSMAs’chains reduced the rotational mobility of spin labels and the random coil-toglobular transition of polymer chains occurred at higher pH value for SL-PSMAs,which showed a slow motion component in the ESR spectra of ***,by increasing the molecular weight of PEGs in IPCs the complexation was increased,which also reduced the rotational motion of spin labels due to interpolymer hydrogen bonding causing a slow motion component in the ESR spectra.©2021 The Authors.

关键词： Electron spin resonance(ESR) Spin labeling Nitroxide radicals poly(styrene-co-maleic acid)s Segmental motion

Remediation of sulfidic wastewater by catalytic oxidation with hydrogen peroxide

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Journal of Environmental Sciences 2009年第12期21卷 1735-1740页

作者： naveed Ahmad Saikat Maitra Binay Kanti Dutta Farooq Ahmad Department of Chemical Engineering Universiti Teknologi PETRONAS Department of Chemical Engineering The Petroleum Institute

Oxidation of sulfide in aqueous solution by hydrogen peroxide was investigated in the presence of hydrated ferric oxide catalyst. The ferric oxide catalyst was synthesized by sol gel technique from ferric chloride and ammonia. The synthesized catalyst was characterized by Fourier transform infrared spectroscopy, X-Ray diffraction analysis, scanning electrom microscope and energy dispersive X-ray analysis. The catalyst was quite effective in oxidizing the sulfide by hydrogen peroxide. The effects of sulfide concentration, catalyst loading, H2O2 dosing and temperature on the kinetics of sulfide oxidation were investigated. Kinetic equations and activation energies for the catalytic oxidation reaction were calculated based on the experimental results.

关键词： catalytic oxidation wastewater kinetic equation hydrogen peroxide sodium sulfide remediation