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A Highly Secured Image Encryption Scheme using Quantum Walk and Chaos

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Computers, Materials & Continua 2022年第10期73卷 657-672页

作者： Muhammad Islam Kamran muazzam a.khan Suliman A.Alsuhibany Yazeed Yasin Ghadi Arshad Jameel Arif Jawad Ahmad Department of Computer Science Quaid-i-Azam UniversityIslamabad45320Pakistan Department of Computer Science College of ComputerQassim UniversityBuraydah51452Saudi Arabia Department of Computer Science and Software Engineering Al Ain UniversityAbu Dhabi15551UAE Institute for Energy and Environment University of StrathclydeGlasgowG11XQUK School of Computing Edinburgh Napier UniversityEdinburghEH105DTUK

The use of multimedia data sharing has drastically increased in the past few decades due to the revolutionary improvements in communication technologies such as the 4th generation(4G)and 5th generation(5G)*** have proposed many image encryption algorithms based on the classical random walk and chaos theory for sharing an image in a secure *** of the classical random walk,this paper proposes the quantum walk to achieve high image *** random walk exhibits randomness due to the stochastic transitions between states,on the other hand,the quantum walk is more random and achieve randomness due to the superposition,and the interference of the wave *** proposed image encryption scheme is evaluated using extensive security metrics such as correlation coefficient,entropy,histogram,time complexity,number of pixels change rate and unified average intensity *** experimental results validate the proposed scheme,and it is concluded that the proposed scheme is highly secured,lightweight and computationally *** the proposed scheme,the values of the correlation coefficient,entropy,mean square error(MSE),number of pixels change rate(NPCR),unified average change intensity(UACI)and contrast are 0.0069,7.9970,40.39,99.60%,33.47 and 10.4542 respectively.

关键词： Cryptography chaotic maps logistic map quantum walk security

Numerical solution of the Saint-Venant equations by an efficient hybrid finite-volume/finite-difference method

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Journal of Hydrodynamics 2018年第2期30卷 189-202页

作者： Wencong Lai Abdul a.khan Glenn Department of Civil Engineering Clemson University

A computationally efficient hybrid finite-volume/finite-difference method is proposed for the numerical solution of SaintVenant equations in one-dimensional open channel flows. The method adopts a mass-conservative finite volume discretization for the continuity equation and a semi-implicit finite difference discretization for the dynamic-wave momentum equation. The spatial discretization of the convective flux term in the momentum equation employs an upwind scheme and the water-surface gradient term is discretized using three different schemes. The performance of the numerical method is investigated in terms of efficiency and accuracy using various examples, including steady flow over a bump, dam-break flow over wet and dry downstream channels, wetting and drying in a parabolic bowl, and dam-break floods in laboratory physical models. Numerical solutions from the hybrid method are compared with solutions from a finite volume method along with analytic solutions or experimental measurements. Comparisons demonstrates that the hybrid method is efficient, accurate, and robust in modeling various flow scenarios, including subcritical, supercritical, and transcritical flows. In this method, the QUICK scheme for the surface slope discretization is more accurate and less diffusive than the center difference and the weighted average schemes.

关键词： Hybrid numerical method Saint-Venant equations shallow water flow

1-D coupled non-equilibrium sediment transport modeling for unsteady flows in the discontinuous Galerkin framework

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Journal of Hydrodynamics 2016年第4期28卷 534-543页

作者： Farzam Safarzadeh MALEKI Abdul a.khan Engineering Department Massachusetts Maritime Academy Glenn Department of Civil Engineering Clemson University

A high-resolution, 1-D numerical model has been developed in the discontinuous Galerkin framework to simulate 1-D flow behavior, sediment transport, and morphological evaluation under unsteady flow conditions. The flow and sediment concentration variables are computed based on the one-dimensional shallow water flow equations, while empirical equations are used for entrainment and deposition processes. The sediment transport model includes the bed load and suspended load components. New formulations for Harten-Lax-van Leer （HLL） and Harten-Lax-van Contact （HLLC） are presented for shallow water flow equations that include the bed load and suspended load fluxes. The computational results for the flow and morphological changes after two dam break events are compared with the physical model tests. Results show that the modified HLL and HLLC formulations are robust and can accurately predict morphological changes in highly unsteady flows.

关键词： dam break flow sediment transport modeling Harten-Lax-van Leer (HLL) and Harten-Lax-van Contact (HLLC) fluxfunctions discontinuous Galerkin scheme

Rare earth element(REE) geochemistry of phosphorites of the Sonrai area of Paleoproterozoic Bijawar basin,Uttar Pradesh,India

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Journal of Rare Earths 2012年第5期30卷 507-514页

作者： K.F.khan Shamim A.Dar Saif a.khan Department of Geology Aligarh Muslim UniversityAligarh-202002Uttar PradeshIndia

The rare earth element（REE） data from the Paleoproterozoic Bijawar basin,Sonrai phosphorites were used to interpret the depositional conditions of the *** post archean Australian shales（PAAS） normalized REE patterns of the Sonrai phosphorites were characterized by negative Ce and positive Eu *** rare earth elements（MREE）-enrichment was a characteristic *** showing the diagenetic effects on the REE patterns were *** observed Eu anomaly was indicative of an anoxic（or sulphate reducing） diagenetic environment of phosphate *** of sea water and upwelling during the Paleoproterozoic was responsible for the recording of positive Eu and negative Ce anomalies in the Sonrai phosphorites.

关键词： rare earth elements geochemistry phosphorites Sonrai Bijawar basin Ce anomaly Eu anomaly

A review of friction models in interacting joints for durability design

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Friction 2017年第1期5卷 1-22页

作者： Zulfiqar a.khan Vivek CHACKO Hammad NAZIR NanoCorr Energy & Modelling(NCEM)Research Department of Design & Engineering Bournemouth University Bournemouth United Kingdom

This paper presents a comprehensive review of friction modelling to provide an understanding of design for durability within interacting *** is a complex phenomenon and occurs at the interface of two components in relative *** the last several decades,the effects of friction and its modelling techniques have been of significant interests in terms of industrial *** is however a need to develop a unified mathematical model for friction to inform design for durability within the context of varying operational *** dynamic mechanisms model for the design of control systems has not incorporated friction phenomena due to non-linearity ***,the tribological performance concurrently with the joint dynamics of a manipulator joint applied in hazardous environments needs to be fully *** the dynamics and impact models used in mechanical joints with clearance have also been *** inclusion of reliability and durability during the design phase is very important for manipulators which are deployed in harsh environmental and operational *** revolute joint is susceptible to failures such as in heavy manipulators these revolute joints can be represented by lubricated conformal sliding *** presence of pollutants such as debris and corrosive constituents has the potential to alter the contacting surfaces,would in turn affect the performance of revolute joints,and puts both reliability and durability of the systems at greater risks of *** literature is identified and a review on the latest developments of the science of friction modelling is presented *** review is based on a large volume of *** in the relevant field have been identified to capitalise on for future ***,this review will bring significant benefits to researchers,academics and industry professionals.

关键词： friction dynamics joint clearance numerical models impact durability

Mitigation of tribocorrosion of metals in aqueous solutions by potential-enhanced adsorption of surfactants

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Friction 2023年第5期11卷 801-819页

作者： Chenxu LIU Yu TIAN Zulfiqar a.khan Yonggang MENG State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China NanoCorr Energy&Modelling Research GroupBournemouth UniversityBournemouthUK

Corrosion and corrosive wear occur commonly on metals surface in aqueous *** electric field is usually considered as one of the factors to accelerate corrosion or corrosive wear of materials in the presence of conventional *** work aims to reposition widely believed perspective by experimental justification which have been conducted in aqueous solutions containing *** potential of metal surfaces was modulated externally within the electrochemical potential window of the metal electrode-solution-counter electrode system,which actively regulated the adsorption or desorption of surfactant molecule in the aqueous solution over the electrodes to form a molecular barrier of electron transportation across the electrode–electrolyte *** advantage of the approach over the anodic passivation is negligible redox reactions on the protected electrode surface while a better lubricious and wear resistant film than oxide is maintained in the *** of several metal/metal and metal/ceramic were tested by employing a ball-on-disc tribometer with anionic and cationic surfactants *** anionic surfactant as the modifier,positive surface potential enables coefficient of friction to be decreased by promoting the formation of adsorption film on metal surface in aqueous *** cationic surfactant,negative surface potential plays a role in decreasing the coefficient of *** diagrams of friction and wear in wide ranges of surfactant concentration and surface potential were plotted for the tested metal/metal and metal/ceramic *** results indicate that the adsorption behavior of molecules or ions at the metal–aqueous interface can be well regulated when an external electric field is present without inducing corrosion or corrosive wear.

关键词： corrosive wear metal electric field surfactant adsorption

Review of Techniques for Integrating Security in Software Development Lifecycle

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Computers, Materials & Continua 2025年第1期82卷 139-172页

作者： Hassan Saeed Imran Shafi Jamil Ahmad Adnan Ahmed khan Tahir Khurshaid Imran Ashraf College of Electrical and Mechanical Engineering National University of Sciences and Technology(NUST)Rawalpindi46604Pakistan Department of Computer Science Abasyn University Islamabad CampusIslamabad45510Pakistan Military College of Signals National University of Sciences and Technology(NUST)Rawalpindi46600Pakistan Department of Electrical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea Department of Information and Communication Engineering Yeungnam UniversityGyeongsan38541Republic of Korea

Software-related security aspects are a growing and legitimate concern,especially with 5G data available just at our *** conduct research in this field,periodic comparative analysis is needed with the new techniques coming up *** purpose of this study is to review the recent developments in the field of security integration in the software development lifecycle(SDLC)by analyzing the articles published in the last two decades and to propose a way *** review follows Kitchenham’s review *** review has been divided into three main stages including planning,execution,and *** the selected 100 articles,it becomes evident that need of a collaborative approach is necessary for addressing critical software security risks(CSSRs)through effective risk management/estimation *** risks using a numeric scale enables a comprehensive understanding of their severity,facilitating focused resource allocation and mitigation *** a comprehensive understanding of potential vulnerabilities and proactive mitigation efforts facilitated by protection poker,organizations can prioritize resources effectively to ensure the successful outcome of projects and initiatives in today’s dynamic threat *** review reveals that threat analysis and security testing are needed to develop automated tools for the *** estimation of effort required to prioritize potential security risks is a big challenge in software *** accuracy of effort estimation can be further improved by exploring new techniques,particularly those involving deep *** is also imperative to validate these effort estimation methods to ensure all potential security threats are *** challenge is selecting the right model for each specific security *** achieve a comprehensive evaluation,researchers should use well-known benchmark checklists.

关键词： Software development lifecycle systematic literature review critical software security risks national institute of standards and technology DevSecOps open web application security project McGraw’s touch points

Second Law Analysis and Optimization of Elliptical Pin Fin Heat Sinks Using Firefly Algorithm

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Computers, Materials & Continua 2020年第11期65卷 1015-1032页

作者： Nawaf N.Hamadneh Waqar a.khan Ilyas khan Department of Basic Sciences College of Science and Theoretical StudiesSaudi Electronic UniversityRiyadh11673Saudi Arabia Department of Mechanical Engineering College of EngineeringPrince Mohammad Bin Fahd UniversityAl Khobar31952Saudi Arabia Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh City72915Vietnam

One of the most significant considerations in the design of a heat sink is thermal management due to increasing thermal flux and miniature in *** heat sinks utilize plate or pin fins depending upon the required heat dissipation *** are designed to optimize overall *** pin fin heat sinks enhance heat transfer rates and reduce the pumping *** this study,the Firefly Algorithm is implemented to optimize heat sinks with elliptical *** pin-fins are arranged in an inline *** nature-inspired metaheuristic algorithm performs powerfully and efficiently in solving numerical global optimization *** on mass,energy,and entropy balance,three models are developed for thermal resistance,hydraulic resistance,and entropy generation rate in the heat *** major axis is used as the characteristic length,and the maximum velocity is used as the reference *** entropy generation rate comprises the combined effect of thermal resistance and pressure *** total EGR is minimized by utilizing the firefly *** optimization model utilizes analytical/empirical correlations for the heat transfer coefficients and friction *** is shown that both thermal resistance and pressure drop can be simultaneously optimized using this *** is demonstrated that the performance of FFA is much better than PPA.

关键词： Firefly algorithm mathematical models entropy generation rate elliptical pin-fin heat sinks thermal resistance pressure drop

High Voltage Direct Current (HVDC) Transmission: Future Expectation for Pakistan

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CSEE Journal of Power and Energy Systems 2019年第1期5卷 82-86页

作者： Kamran Hafeez Shahid a.khan Electrical Engineering Department CIIT Islamabad campus Pakistan

An HVDC transmission system for bulk power transfer over longer distance offers numerous advantages over an alternating current(AC)transmission system,such as direct integration of networks operating at different frequencies,comparatively low line losses on account of constant current and absence of *** paper presents details about HVDC power transmission systems and power converter *** concerning integration of electrical power generated by alternate sources(i.e.,wind,onshore and offshore)into the national grid of Pakistan using HVDC technology are also *** studies revealed that the energy crisis of countries like Pakistan can be mitigated to a larger extent with the use of HVDC transmission systems.

关键词： HVDC renewable energy transmission systems wind Energy