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Electrostatic Dust Acoustic Solitons in Pair-Ion-Electron Plasmas

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Chinese Physics Letters 2012年第6期29卷 207-210页

作者： hafeez ur rehman Theoretical Plasma Physics Division Pakistan Institute of Nuclear Science and Technology(PINSTECH)P.O.NiloreIslamabadPakistan Department of Physics and Applied Mathematics Pakistan Institute of Engineering and Applied Sciences(PIEAS)P.O.NiloreIslamabadPakistan

Using the reductive perturbation method,a Korteweg-de Vries (KdV) equation is derived to study the nonlinear properties of electrostatic collisionless dust acoustic solitons in pair-ion-electron (p-i-e) *** Buid model is chosen for positive ions,negative ions,and the fraction of electrons and charged (both positive and negative)dynamic dust *** is realized that electrostatic hump structures can be found when the dust particles are positively charged,and electrostatic dip structures can be detected for negatively charged dust *** solutions for these dust acoustic solitous are plotted and their characteristics are *** is found that the amplitude and width of the electrostatic dust acoustic solitons increase when the density of the dust particles and/or the temperature of the negative ions increases,and that the amplitude and width of these solitons decrease when the temperature of the positive ions *** pair-ion plasmas mimic electron-positron plasmas,our results might be helpful in understanding the nonlinear dust acoustic solitary waves in super dense astronomical bodies like neutron stars.

关键词： particles electrostatic solitons

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

Polyhydroxyurethanes from Biobased Monomers and CO_(2):A Bridge between Sustainable Chemistry and CO_(2) Utilization

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Chinese Journal of Chemistry 2024年第6期42卷 652-685页

作者： Tharinee Theerathanagorn Tanika Kessaratikoon hafeez ur rehman Valerio D'Elia Daniel Crespy VISTEC Advanced Laboratory for Environment-Related Inorganic and Organic Syntheses Department of Materials Science and EngineeringVidyasirimedhi Institute of Science and Technology21210Wang ChanRayongThailand Department of Materials Science and Engineering Vidyasirimedhi Institute of Science and Technology21210Wang ChanRayongThailand

Polyhydroxyurethanes(PHUs)have received considerable attention in the last decade as potential alternatives to traditional phosgene-based polyurethanes(PUs).The development of suitable 5CC(five membered-ring cyclic carbonate)precursors bearing multiple carbonate moieties(multi-5CCs)is a key requisite for preparing PHUs by polyaddition reaction with bis-or *** sustainable PHUs from CO_(2)-based five-membered cyclic carbonates(5CCs)obtained from biobased epoxides is a valuable strategy to bridge CO_(2) utilization and the upcycling of renewable *** this context,while many multi-5CC monomers reported in the literature are oil-based,recent efforts have led to the development of a large variety of multifunctional 5CCs that are produced by the combination of CO_(2) and renewable resources such as fatty acids and vegetable oils,lignin,terpenes,and *** this work,recent crucial advances(2019—2023)on PHUs prepared from bis-and multi-5CCs produced from CO_(2) and(partially/potentially)biobased substrates are reviewed with respect to their synthesis,thermal and mechanical properties,and their recent,emerging applications.

关键词： CO_(2) conversion Polyhydroxyurethanes Cyclic carbonates Biobased compounds Fatty acids Functional polymers Monomers Renewable resources

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

Influence of Seed Priming on Performance and Water Productivity of Direct Seeded Rice in Alternating Wetting and Drying

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Rice science 2015年第4期22卷 189-196页

作者： hafeez ur rehman Muhammad KAMRAN Shahzad Maqsood Ahmed BASRA Irfan AFZAL Muhammad FAROOQ Department of Agronomy University of AgricultureFaisalabad Institute of Agriculture University of Western Australia College of Food and Agricultural Sciences King Saud University

Direct seeded rice is promising alternative to traditional transplanting, but requires appropriate crop and water management to maintain yield performance and achieve high water productivity. Present study evaluated the effect of seed priming and irrigation on crop establishment, tillering, agronomic traits, paddy yield, grain quality and water productivity of direct seeded rice in alternate wetting and drying （DSR-AWD） in comparison with direct seeded rice at field capacity （DSR- FC）. Seed priming treatments were osmo-priming with KCI （2.2%）, CaCI2 （2.2%） and moringa leaf extracts （MLE, 3.3%） including hydro-priming as control. Among the treatments, seed osmo-primed with MLE emerged earlier and had higher final emergence, followed by osmo-priming with CaCI2. Tillering emergence rate and number of tillers per plant were the highest for seed priming with CaCI2 in DSR- AWD. Total productive and non-productive tillers, panicle length, biological and grain yields, harvest index were highest for seed priming with MLE or CaCI2 in DSR-AWD. Similarly, grain quality, estimated in terms of normal grains, abortive and chalky grains, was also the highest in DSR-AWD with MLE osmo-priming. Benefit cost ratio and water productivity was also the highest in DSR-AWD for seed priming with MLE. In conclusion, seed priming with MLE or CaCI2 can be successfully employed to improve the direct seeded rice performance when practiced with alternate wetting and drying irrigation.

关键词： crop establishment grain filling rate seed priming water productivity yield direct seededrice alternating wetting and drying grain quality

Early-Stage Segmentation and Characterization of Brain Tumor

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Computers, Materials & Continua 2022年第10期73卷 1001-1017页

作者： Syed Nauyan Rashid Muhammad Hanif Usman Habib Akhtar Khalil Omair Inam hafeez ur rehman Department of Computer Science National University of Computer and Emerging Sciences IslamabadPeshawar CampusPakistan Faculty of Computer Science and Engineering Ghulam Ishaq Khan(GIK)Institute of Engineering Sciences and TechnologyTopiPakistan IFahja Pvt Limited PeshawarPakistan Department of Electrical and Computer Engineering COMSATS University IslamabadPakistan

Gliomas are the most aggressive brain tumors caused by the abnormal growth of brain *** life expectancy of patients diagnosed with gliomas decreases *** gliomas are diagnosed in later stages,resulting in imminent *** average,patients do not survive 14 months after *** only way to minimize the impact of this inevitable disease is through early *** Magnetic Resonance Imaging(MRI)scans,because of their better tissue contrast,are most frequently used to assess the brain *** manual classification of MRI scans takes a reasonable amount of time to classify brain *** this,dealing with MRI scans manually is also cumbersome,thus affects the classification *** eradicate this problem,researchers have come up with automatic and semiautomatic methods that help in the automation of brain tumor classification ***,many techniques have been devised to address this issue,the existing methods still struggle to characterize the enhancing *** is because of low variance in enhancing region which give poor contrast in MRI *** this study,we propose a novel deep learning based method consisting of a series of steps,namely:data pre-processing,patch extraction,patch pre-processing,and a deep learning model with tuned hyper-parameters to classify all types of gliomas with a focus on enhancing *** trained model achieved better results for all glioma classes including the enhancing *** improved performance of our technique can be attributed to several ***,the non-local mean filter in the pre-processing step,improved the image detail while removing irrelevant ***,the architecture we employ can capture the non-linearity of all classes including the enhancing ***,the segmentation scores achieved on the Dice Similarity Coefficient(DSC)metric for normal,necrosis,edema,enhancing and non-enhancing tumor classes are 0.95,0.97,0.91,0.93,0.95;respectively.

关键词： Segmentation CNN characterization brain tumor MRI

Seed priming improves early seedling vigor, growth and productivity of spring maize

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Journal of Integrative Agriculture 2015年第9期14卷 1745-1754页

作者： hafeez ur rehman Hassan Iqbal Shahzad M A Basra Irfan Afzal Muhammad Farooq Abdul Wakeel WANG Ning Seed Physiology Laboratory Department of Crop PhysiologyUniversity of Agriculture Department of Agronomy University of Agriculture Institute of Soil and Environmental Sciences University of Agriculture Agricultural Information Institute Chinese Academy of Agricultural Sciences

Potential of seed priming treatments in improving the performance of early planted maize was evaluated against timely planting. Seeds of maize hybrid FH-810 were soaked in water (hydropriming), CaCl2 (2.2%, osmopriming), moringa leaf extracts (MLE 3.3%, osmopriming) and salicylic acid (SA, 50 mg L–1, hormonal priming) each for 18 h. Untreated and hydroprimed seeds were taken as control. Seeds primed with SA took less time in emergence and had high vigor in early planted maize. Amongst treatments, hormonal priming, reduced the electrical conductivity, increased the leaf relative and chlorophyl contents fol owed by osmopriming with CaCl2 at seedling stage. Likewise, plant height, grain rows and 1 000-grain weight, grain and biological yield and harvest index were also improved by seed priming;however hormonal priming and osmopriming with MLE were more effective in this regard. Improved yield performance by hormonal priming or osmopriming with MLE in early planting primarily owed to increased leaf area index, crop growth and net assimilation rates, and maintenance of green leaf area at maturity. In conclusion, osmopriming with MLE and hormonal priming with SA were the most economical treatments in improving productivity of early planted spring maize through stimulation of early seedling growth at low temperature.

关键词： low temperature membrane permeability organic stimulants moringa leaf extracts salicylic acid leaf area duration yield

Seed Priming Influence on Early Crop Growth, Phenological Development and Yield Performance of Linola (Linum usitatissimum L.)

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Journal of Integrative Agriculture 2014年第5期13卷 990-996页

作者： hafeez ur rehman Muhammad Qaiser Nawaz Shahzad Maqsood Ahmed Basra Irfan Afzal Azra Yasmeen Fayyaz ul-Hassan Seed Physiology Laboratory Department of Crop Physiology University of Agriculture Faisalabad Soil Salinity Research Institute Pindi Bhatian College of Agriculture Bahuddin Zakriya University Department of Agronomy PMAS University of Arid Agriculture

Reduced early crop growth and limited branching are amongst yield limiting factors of linola. Field response of seed priming treatments viz. 50 mmol L^-1 salicylic acid （SA）, 2.2% CaCl2 and 3.3% moringa leaf extract （MLE） including untreated dry and hydropriming controls was evaluated on early crop growth and yield performance of linola. Osmopriming with CaCl2 reduced emergence time and produced the highest seedling fresh and dry weights including Chl. a contents. Osmopriming with CaCl2 reduced crop branching and flowering and maturity times and had the maximum plant height, number of branches, tillers, pods and seeds per pod followed by MLE. Increase in seed weight, biological and seed yields was 9.30, 34.16 and 39.49%, harvest index （4.12%） and oil contents （13.39%） for CaCl2 osmopriming. Positive relationship between emergence and seedling vigor traits, 100-seed weight, seed yield with maturity time, 100-seed weight and seed yield were found. The study concludes that seed osmopriming with CaC12 or MLE can play significant role to improve early crop growth and seed yields of linola.

关键词： linseed oil quality stand establishment CaCl2