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Motion synchronization in a dual redundant HA/EHA system by using a hybrid integrated intelligent control design

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Chinese Journal of Aeronautics 2016年第3期29卷 789-798页

作者： Waheed ur rehman Wang Shaoping Wang Xingjian Fan Lei Kamran Ali shah School of Automation Science and Electrical Engineering Beihang University

This paper presents an integrated fuzzy controller design approach to synchronize a dis- similar redundant actuation system of a hydraulic actuator （HA） and an electro-hydrostatic actu- ator （EHA） with system uncertainties and disturbances. The motion synchronous control system consists of a trajectory generator, an individual position controller for each actuator, and a fuzzy force tracking controller （FFTC） for both actuators. The trajectory generator provides the desired motion dynamics and designing parameters of the trajectory which are taken according to the dynamic characteristics of the EHA. The position controller consists of a feed-forward controller and a fuzzy position tracking controller （FPTC） and acts as a decoupled controller, improving posi- tion tracking performance with the help of the feed-forward controller and the FPTC. The FFTC acts as a coupled controller and takes into account the inherent coupling effect. The simulation results show that the proposed controller not only eliminates initial force fighting by synchronizing the two actuators, but also improves disturbance rejection performance.

关键词： Dissimilar redundant:Electro-hydrostatic actuator Fuzzy control:Hydraulic actuator Motion synchronization Redundant systems

Asymmetric Key Cryptosystem for Image Encryption by Elliptic Curve over Galois Field GF(2^(n))

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Computers, Materials & Continua 2023年第8期76卷 2033-2060页

作者： Mohammad Mazyad Hazzazi Hafeez ur rehman Tariq shah Hajra Younas Department of Mathematics College of ScienceKing Khalid UniversityAbha61421Saudi Arabia Department of Mathematics Quaid-i-Azam UniversityIslamabadPakistan

Protecting the integrity and secrecy of digital data transmitted through the internet is a growing *** this paper,we introduce an asymmetric key algorithm for specifically processing images with larger bit *** overcome the separate flaws of elliptic curve cryptography(ECC)and the Hill cipher(HC),we present an approach to picture encryption by combining these two encryption *** addition,to strengthen our scheme,the group laws are defined over the rational points of a given elliptic curve(EC)over a Galois field(GF).The exclusive-or(XOR)function is used instead of matrix multiplication to encrypt and decrypt the data which also refutes the need for the inverse of the key *** integrating the inverse function on the pixels of the image,we have improved system security and have a wider key ***,through comprehensive analysis of the proposed scheme with different available analyses and standard attacks,it is confirmed that our proposed scheme provides improved speed,security,and efficiency.

关键词： Elliptic curve Galois field group law hill cipher

Design of Nonlinear Components Over a Mordell Elliptic Curve on Galois Fields

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Computers, Materials & Continua 2022年第4期71卷 1313-1329页

作者： Hafeez ur rehman Tariq shah Amer Aljaedi Mohammad Mazyad Hazzazi Adel RAlharbi Department of Mathematics Quaid-i-Azam UniversityIslamabadPakistan College of Computing and Information Technology University of TabukTabuk71491Saudi Arabia Department of Mathematics College of ScienceKing Khalid UniversityAbhaSaudi Arabia

Elliptic curve cryptography ensures more safety and reliability than other public key cryptosystems of the same key *** recent years,the use of elliptic curves in public-key cryptography has increased due to their complexity and *** kinds of substitution boxes are proposed to address the substitution process in the cryptosystems,including dynamical,static,and elliptic curve-based ***,elliptic curve-based S-boxes are based on prime field GF(p)but in this manuscript;we propose a new technique of generating S-boxes based on mordell elliptic curves over the Galois field GF(2n).This technique affords a higher number of possibilities to generate S-boxes,which helps to increase the security of the *** robustness of the proposed S-boxes against the well-known algebraic and statistical attacks is analyzed to classify its potential to generate confusion and achieve up to the mark results compared to the various *** majority logic criterion results determine that the proposed S-boxes have up to the mark cryptographic strength.

关键词： Galois field elliptic curve S-box nonlinearity

Mordell Elliptic Curve Based Design of Nonlinear Component of Block Cipher

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Computers, Materials & Continua 2022年第11期73卷 2913-2930页

作者： Hafeez ur rehman Tariq shah Mohammad Mazyad Hazzazi Ali Alshehri Bassfar Zaid Department of Mathematics Quaid-i-Azam UniversityIslamabadPakistan Department of Mathematics College of ScienceKing Khalid UniversityAbhaSaudi Arabia Department of Computer Science University of TabukTabuk71491Saudi Arabia Department of Information Technology University of TabukTabuk71491Saudi Arabia

Elliptic curves(ECs)are deemed one of the most solid structures against modern computational attacks because of their small key size and high *** many well-known cryptosystems,the substitution box(Sbox)is used as the only nonlinear portion of a security ***,it has been shown that using dynamic S-boxes rather than static S-boxes increases the security of a *** conferred study also extends the practical application of ECs in designing the nonlinear components of block ciphers in symmetric key *** this study,instead of the Mordell elliptic curve(MEC)over the prime field,the Galois field has been engaged in constructing the S-boxes,the main nonlinear component of the block ***,the proposed scheme uses the coordinates of MEC and the operation of the Galois field to generate a higher number of S-boxes with optimal nonlinearity,which increases the security of *** proposed S-boxes resilience against prominent algebraic and statistical attacks is evaluated to determine its potential to induce confusion and produce acceptable results compared to other ***,the majority logic criteria(MLC)are used to assess the new S-boxes usage in the image encryption application,and the outcomes indicate that they have significant cryptographic strength.

关键词： Galois field Mordell elliptic curve nonlinearity substitution box

Bioassay studies of cobalt (Ⅱ) complexes of modified diamine

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Frontiers of Chemistry in China 2011年第2期6卷 98-104页

作者： Saeed-ur-rehman Muhammad IKRAM Sadia rehman shah NAWAZ Institute of Chemical Sciences University of PeshawarPeshawar 25120Pakistan

Coordination compounds of modified diamine,the basic unit of which are ethylenediamine,with that of Co(Ⅱ)are *** modified diamines are ethylenediaceticacid(EDDA)and N,N,N,N-tetaraethylene-1,2-diamine(TEEDA).These diamines are characterized through ^(1)H-NMR,^(13)C-NMR,elemental analysis and IR ***(Ⅱ)complexes of these two ligands were prepared and characterized by physical measurements including elemental analysis,IR,UVVisible,magnetic susceptibilities and conductance *** activities are also carried out in order to investigate the biological activity upon *** were screened against four pathogenic bacteria like Escherichia coli,Pseudomonas aeroginosa,Klesbella pneumonia and Staphylococcus *** results showed significant enhancement in activities.

关键词： EDDA TEEDA cobalt complexes antibacterial studies

An Efficient Impersonation attack Detection Method in Fog Computing

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Computers, Materials & Continua 2021年第7期68卷 267-281页

作者： Jialin Wan Muhammad Waqas Shanshan Tu Syed Mudassir Hussain Ahsan shah Sadaqat ur rehman Muhammad Hanif Engineering Research Center of Intelligent Perception and Autonomous Control Faculty of Information TechnologyBeijing University of TechnologyBeijing100124China Faculty of Computer Science and Engineering Ghulam Ishaq Khan Institute of Engineering Sciences and TechnologyTopi23460Pakistan Department of Electronics Engineering FICTBalochistan University of Information TechnologyEngineering and Management SciencesQuetta87300Pakistan Department of Computer Science Namal InstituteMianwali42200Pakistan

Fog computing paradigm extends computing,communication,storage,and network resources to the network’s *** the fog layer is located between cloud and end-users,it can provide more convenience and timely services to ***,in fog computing(FC),attackers can behave as real fog nodes or end-users to provide malicious services in the *** attacker acts as an impersonator to impersonate other legitimate ***,in this work,we present a detection technique to secure the FC ***,we model a physical layer key generation based on wireless channel *** generate the secret keys between the legitimate users and avoid impersonators,we then consider a Double Sarsa technique to identify the impersonators at the receiver *** compare our proposed Double Sarsa technique with the other two methods to validate our work,i.e.,Sarsa and *** simulation results demonstrate that the method based on Double Sarsa outperforms Sarsa and Q-learning approaches in terms of false alarm rate(FAR),miss detection rate(MDR),and average error rate(AER).

关键词： Fog computing double Sarsa attack detection physical layer key security

A Novel Parallel Computing Confidentiality Scheme Based on Hindmarsh-Rose Model

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Computers, Materials & Continua 2023年第8期76卷 1325-1341页

作者： Jawad Ahmad Mimonah Al Qathrady Mohammed SAlshehri Yazeed Yasin Ghadi Mujeeb ur rehman Syed Aziz shah School of Computing Engineering and the Built EnvironmentEdinburgh Napier UniversityEdinburghEH105DTUK Department of Information Systems College of Computer Science and Information SystemsNajran UniversityNajran61441Saudi Arabia Department of Computer Science College of Computer Science and Information SystemsNajran UniversityNajran61441Saudi Arabia Department of Computer Science Al Ain UniversityAbu Dhabi112612United Arab Emirates School of Science Technology and HealthYork St John UniversityYorkYO317EXUK Research Centre for Intelligent Healthcare Coventry UniversityCoventryCV15FBUK

Due to the inherent insecure nature of the Internet,it is crucial to ensure the secure transmission of image data over this ***,given the limitations of computers,it becomes evenmore important to employ efficient and fast image encryption *** 1D chaotic maps offer a practical approach to real-time image encryption,their limited flexibility and increased vulnerability restrict their practical *** this research,we have utilized a 3DHindmarsh-Rosemodel to construct a secure *** randomness of the chaotic map is assessed through standard *** proposed system enhances security by incorporating an increased number of system parameters and a wide range of chaotic parameters,as well as ensuring a uniformdistribution of chaotic signals across the entire value ***,a fast image encryption technique utilizing the new chaotic system is *** novelty of the approach is confirmed through time complexity *** further strengthen the resistance against cryptanalysis attacks and differential attacks,the SHA-256 algorithm is employed for secure key *** results through a number of parameters demonstrate the strong cryptographic performance of the proposed image encryption approach,highlighting its exceptional suitability for secure ***,the security of the proposed scheme has been compared with stateof-the-art image encryption schemes,and all comparison metrics indicate the superior performance of the proposed scheme.

关键词： Hindmarsh-rose model image encryption SHA-256 parallel computing

Platform motion minimization using model predictive control of a floating offshore wind turbine

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Theoretical & Applied Mechanics Letters 2021年第5期11卷 291-295页

作者： Kamran Ali shah Ye Li Ryozo Nagamune Yarong Zhou Waheed ur rehman Multi-function Towing Tank Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Ocean Engineering School of Naval ArchitectureOcean&Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Mechanical Engineering The University of British ColumbiaVancouverBCV6T1Z4 Canada Swedish College of Engineering and Technology Rahim Yar Khan Pakistan

Wind turbines are installed offshore with the assistance of a floating platform to help meet the world’s increasing energy ***,the incident wind and extra incident wave disturbances have an impact on the performance and operation of the floating offshore wind turbine(FOWT)in comparison to bottom-fixed wind *** this paper,model predictive control(MPC)is utilized to overcome the limitation caused by platform *** to the ease of control synthesis,the MPC is developed using a simplified model instead of high fidelity simulation *** performance of the controller is verified in the presence of realistic wind and wave *** study demonstrates the effectiveness of MPC in reducing platform motions and rotor/generator speed regulation of FOWTs.

关键词： Wind energy Floating offshore wind turbine Platform motion Model predictive control

Transfer of Heavy Metals from Soils to Vegetables and Associated Human Health Risks at Selected Sites in Pakistan

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Pedosphere 2018年第4期28卷 666-679页

作者： Zahir ur rehman Sardar KHAN Mohammad Tahir shah Mark L.BRUSSEAU Said Akbar KHAN Jon MAINHAGU Department of Environmental Sciences University of Peshawar School of Earth and Environmental Sciences University of Arizona National Centre of Excellence in Geology University of Peshawar

Contamination of the food chain with heavy metals is considered as one of the major environmental pathways of human exposure to metals leading to potential health risks. This study aimed to investigate the concentrations of heavy metals such as copper （Cu）, zinc （Zn）, chromium （Cr）, nickel （Ni）, and manganese （Mn） in agricultural soils and food crops （fruit, leaf, and root vegetables）, and their associated health risks to the local population in selected southern districts of Khyber Pakhtunkhwa Province, Pakistan. The concentrations of the selected metals in soil varied over a wide range, in the following decreasing order： Mn 〉 Zn 〉 Cr 〉 Ni 〉 Cu. The bioaccunmlation of metals in vegetables was within the permissible risk limits, except for Cr which showed higher contamination in all the tested food crops. The trend of metal transfer factors for different vegetables was in the order of Cu 〉 Ni 〉 Cr 〉 Mn 〉 Zn, while the calculated daily intake of metals （DIM） in adults and children through consumption of food crops was in the decreasing order of Mn 〉 Zn 〉 Ni 〉 Cr 〉 Cu. The health risk index （HRI） values for the heavy metals for both adults and children were less than 1. Therefore, no significant health risk is anticipated for the local consumers through ingestion of these food crops.

关键词： contamination daily intake food crops metal accumulation metal pollution metal transfer factor risk index