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Asymmetric Key Cryptosystem for Image Encryption by Elliptic Curve over Galois Field GF(2^(n))
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作者 Mohammad Mazyad Hazzazi hafeez ur rehman +1 位作者 Tariq Shah Hajra Younas 《Computers, Materials & Continua》 SCIE EI 2023年第8期2033-2060,共28页
Protecting the integrity and secrecy of digital data transmitted through the internet is a growing problem.In this paper,we introduce an asymmetric key algorithm for specifically processing images with larger bit valu... Protecting the integrity and secrecy of digital data transmitted through the internet is a growing problem.In this paper,we introduce an asymmetric key algorithm for specifically processing images with larger bit values.To 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 approaches.In 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 matrix.By integrating the inverse function on the pixels of the image,we have improved system security and have a wider key space.Furthermore,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. 展开更多
关键词 Elliptic curve Galois field group law hill cipher
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Rice-wheat comparative genomics:Gains and gaps
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作者 Akila Wijerathna-Yapa Ruchi Bishnoi +11 位作者 Buddhini Ranawaka Manu Maya Magar hafeez ur rehman Swati G.Bharad Michal T.Lorenc Vinita Ramtekey Sasha Gohar Charu Lata Md.Harun-Or-Rashid Maryam Razzaq Muhammad Sajjad Bhoja R.Basnet 《The Crop Journal》 SCIE CSCD 2024年第3期656-669,共14页
Rice and wheat provide nearly 40%of human calorie and protein requirements.They share a common ancestor and belong to the Poaceae(grass)family.Characterizing their genetic homology is crucial for developing new cultiv... Rice and wheat provide nearly 40%of human calorie and protein requirements.They share a common ancestor and belong to the Poaceae(grass)family.Characterizing their genetic homology is crucial for developing new cultivars with enhanced traits.Several wheat genes and gene families have been characterized based on their rice orthologs.Rice–wheat orthology can identify genetic regions that regulate similar traits in both crops.Rice–wheat comparative genomics can identify candidate wheat genes in a genomic region identified by association or QTL mapping,deduce their putative functions and biochemical pathways,and develop molecular markers for marker-assisted breeding.A knowledge of gene homology facilitates the transfer between crops of genes or genomic regions associated with desirable traits by genetic engineering,gene editing,or wide crossing. 展开更多
关键词 Comparative genomics ORTHOLOGS GENES SYNTENY Genetic engineering Molecular breeding
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Design of Nonlinear Components Over a Mordell Elliptic Curve on Galois Fields 被引量:1
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作者 hafeez ur rehman Tariq Shah +2 位作者 Amer Aljaedi Mohammad Mazyad Hazzazi Adel RAlharbi 《Computers, Materials & Continua》 SCIE EI 2022年第4期1313-1329,共17页
Elliptic curve cryptography ensures more safety and reliability than other public key cryptosystems of the same key size.In recent years,the use of elliptic curves in public-key cryptography has increased due to their... Elliptic curve cryptography ensures more safety and reliability than other public key cryptosystems of the same key size.In recent years,the use of elliptic curves in public-key cryptography has increased due to their complexity and reliability.Different kinds of substitution boxes are proposed to address the substitution process in the cryptosystems,including dynamical,static,and elliptic curve-based methods.Conventionally,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 cryptosystem.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 schemes.The majority logic criterion results determine that the proposed S-boxes have up to the mark cryptographic strength. 展开更多
关键词 Galois field elliptic curve S-BOX NONLINEARITY
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Mordell Elliptic Curve Based Design of Nonlinear Component of Block Cipher
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作者 hafeez ur rehman Tariq Shah +2 位作者 Mohammad Mazyad Hazzazi Ali Alshehri Bassfar Zaid 《Computers, Materials & Continua》 SCIE EI 2022年第11期2913-2930,共18页
Elliptic curves(ECs)are deemed one of the most solid structures against modern computational attacks because of their small key size and high security.In many well-known cryptosystems,the substitution box(Sbox)is used... Elliptic curves(ECs)are deemed one of the most solid structures against modern computational attacks because of their small key size and high security.In many well-known cryptosystems,the substitution box(Sbox)is used as the only nonlinear portion of a security system.Recently,it has been shown that using dynamic S-boxes rather than static S-boxes increases the security of a cryptosystem.The conferred study also extends the practical application of ECs in designing the nonlinear components of block ciphers in symmetric key cryptography.In 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 ciphers.Also,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 cryptosystems.The 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 schemes.Also,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. 展开更多
关键词 Galois field Mordell elliptic curve NONLINEARITY substitution box
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Polyhydroxyurethanes from Biobased Monomers and CO_(2):A Bridge between Sustainable Chemistry and CO_(2) Utilization
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作者 Tharinee Theerathanagorn Tanika Kessaratikoon +2 位作者 hafeez ur rehman Valerio D'Elia Daniel Crespy 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2024年第6期652-685,共34页
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 ca... 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 polyamines.Producing 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 substrates.In 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 sugars.In 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. 展开更多
关键词 CO_(2) conversion Polyhydroxyurethanes Cyclic carbonates Biobased compounds Fatty acids Functional polymers MONOMERS Renewable resources
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Influence of Seed Priming on Performance and Water Productivity of Direct Seeded Rice in Alternating Wetting and Drying 被引量:6
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作者 hafeez ur rehman Muhammad KAMRAN +2 位作者 Shahzad Maqsood Ahmed BASRA Irfan AFZAL Muhammad FAROOQ 《Rice science》 SCIE CSCD 2015年第4期189-196,共8页
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 t... 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. 展开更多
关键词 crop establishment grain filling rate seed priming water productivity YIELD direct seededrice alternating wetting and drying grain quality
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Seed priming improves early seedling vigor, growth and productivity of spring maize 被引量:3
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作者 hafeez ur rehman Hassan Iqbal +4 位作者 Shahzad M A Basra Irfan Afzal Muhammad Farooq Abdul Wakeel WANG Ning 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第9期1745-1754,共10页
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%, osmoprimin... 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. 展开更多
关键词 low temperature membrane permeability organic stimulants moringa leaf extracts salicylic acid leaf area duration YIELD
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Seed Priming Influence on Early Crop Growth, Phenological Development and Yield Performance of Linola (Linum usitatissimum L.) 被引量:4
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作者 hafeez ur rehman Muhammad Qaiser Nawaz +3 位作者 Shahzad Maqsood Ahmed Basra Irfan Afzal Azra Yasmeen Fayyaz ul-Hassan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第5期990-996,共7页
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... 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. 展开更多
关键词 LINSEED oil quality stand establishment CACL2
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Early-Stage Segmentation and Characterization of Brain Tumor
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作者 Syed Nauyan Rashid Muhammad Hanif +3 位作者 Usman Habib Akhtar Khalil Omair Inam hafeez ur rehman 《Computers, Materials & Continua》 SCIE EI 2022年第10期1001-1017,共17页
Gliomas are the most aggressive brain tumors caused by the abnormal growth of brain tissues.The life expectancy of patients diagnosed with gliomas decreases exponentially.Most gliomas are diagnosed in later stages,res... Gliomas are the most aggressive brain tumors caused by the abnormal growth of brain tissues.The life expectancy of patients diagnosed with gliomas decreases exponentially.Most gliomas are diagnosed in later stages,resulting in imminent death.On average,patients do not survive 14 months after diagnosis.The only way to minimize the impact of this inevitable disease is through early diagnosis.The Magnetic Resonance Imaging(MRI)scans,because of their better tissue contrast,are most frequently used to assess the brain tissues.The manual classification of MRI scans takes a reasonable amount of time to classify brain tumors.Besides this,dealing with MRI scans manually is also cumbersome,thus affects the classification accuracy.To eradicate this problem,researchers have come up with automatic and semiautomatic methods that help in the automation of brain tumor classification task.Although,many techniques have been devised to address this issue,the existing methods still struggle to characterize the enhancing region.This is because of low variance in enhancing region which give poor contrast in MRI scans.In 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 region.Our trained model achieved better results for all glioma classes including the enhancing region.The improved performance of our technique can be attributed to several factors.Firstly,the non-local mean filter in the pre-processing step,improved the image detail while removing irrelevant noise.Secondly,the architecture we employ can capture the non-linearity of all classes including the enhancing region.Overall,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. 展开更多
关键词 SEGMENTATION CNN CHARACTERIZATION brain tumor MRI
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Electrostatic Dust Acoustic Solitons in Pair-Ion-Electron Plasmas
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作者 hafeez ur rehman 《Chinese Physics Letters》 SCIE CAS CSCD 2012年第6期207-210,共4页
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) plasmas.The Bu... 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) plasmas.The Buid model is chosen for positive ions,negative ions,and the fraction of electrons and charged (both positive and negative)dynamic dust particles.It 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 particles.Numerical solutions for these dust acoustic solitous are plotted and their characteristics are discussed.It 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 increases.As 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. 展开更多
关键词 PARTICLES ELECTROSTATIC SOLITONS
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