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Amino Acid Encryption method Using Genetic Algorithm for Key Generation

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Computers, materials & Continua 2022年第1期70卷 123-134页

作者： ahmed S.Sakr m.y.Shams Amena mahmoud mohammed zidan Department of Information System Faculty of Computers and InformationMenofia UniversityEgypt Department of machine learning and Information Retrieval Faculty of Artificial IntelligenceKafrelsheikh UniversityEgypt Department of Computer Science Faculty of Computers and InformationKafrelshiekh UniversityEgypt Hurghada Faculty of Computers and Artificial Intelligence South Valley UniversityEgypt

In this new information era,the transfer of data and information has become a very important *** data must be kept secured from unauthorized persons using *** science of cryptography depends not only on complex mathematical models but also on encryption *** acid encryption is a promising model for data *** this paper,we propose an amino acid encryption model with two encryption *** first key is generated randomly using the genetic *** second key is called the protein key which is generated from converting DNA to a protein ***,the protein message and the first key are used in the modified Playfair matrix to generate the cypher *** experimental results show that the proposed model survives against known attacks such as the Brute-force attack and the Ciphertext-only *** addition,the proposed model has been tested over different types of characters including white spaces and special characters,as all the data is encoded to 8-bit *** performance of the proposed model is compared with other models using encryption time and decryption *** model also balances all three principles in the CIA triad.

关键词： Cryptography amino acid genetic algorithm playfair deep learning DNA computing

Grids of stellar models including second harmonic and colors:solar composition(z = 0.0172,X = 0.7024)

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Research in Astronomy and Astrophysics 2015年第12期15卷 2244-2262页

作者： mutlu y?ld?z Ege University Department of Astronomy and Space Sciences

Grids of stellar evolution omy/astrophysics, such as planet hosting are required in many fields of astron- stars, binaries, clusters, chemically peculiar stars, etc. In this study, a grid of stellar evolution models with updated ingredients and recently determined solar abundances is presented. The solar values for the initial abundances of hydrogen, heavy elements and mixing-length parameter are 0.0172, 0.7024 and 1.98, respectively. The mass step is small enough （0.01 m） that interpolation for a given star mass is not required. The range of stellar mass is 0.74 to 10.00m. We present results in different forms of tables for easy and general appli- cation. The second stellar harmonic, required for analysis of apsidal motion of eclips- ing binaries, is also listed. We also construct rotating models to determine the effect of rotation on stellar structure and derive fitting formulae for luminosity, radius and the second harmonic as a function of rotational parameter. We also compute and list colors and bolometric corrections of models required for transformation between theo- retical and observational results. The results are tested for the Sun, the Hyades cluster, the slowly rotating chemically peculiar Am stars and eclipsing binaries with apsidal motion. The theoretical and observational results along isochrones are in good agree- ment. The grids are also applicable to rotating stars provided that equatorial velocity is given.

关键词： stars: interior -- stars: evolution -- binaries: eclipsing -- stars: chemi-cally peculiar

A Genetic Algorithm to Solve Capacity Assignment Problem in a Flow Network

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Computers, materials & Continua 2020年第9期64卷 1579-1586页

作者： ahmed y.Hamed monagi H.Alkinani m.R.Hassan Department of Computer Science Faculty of Computers and InformationSohag UniversitySohag82524Egypt Department of Computer Science and Artificial Intelligence College of Computer Science and EngineeringUniversity of JeddahJeddah21959Saudi Arabia Department of mathematics and Computer Science Faculty of ScienceAswan UniversityAswan81528Egypt

Computer networks and power transmission networks are treated as capacitated flow networks.A capacitated flow network may partially fail due to ***,the capacity of each edge should be optimally assigned to face critical situations-i.e.,to keep the network functioning normally in the case of failure at one or more *** robust design problem(RDP)in a capacitated flow network is to search for the minimum capacity assignment of each edge such that the network still survived even under the edge’s *** RDP is known as ***,capacity assignment problem subject to system reliability and total capacity constraints is studied in this *** problem is formulated mathematically,and a genetic algorithm is proposed to determine the optimal *** optimal solution found by the proposed algorithm is characterized by maximum reliability and minimum total *** numerical examples are presented to illustrate the efficiency of the proposed approach.

关键词： Flow network capacity assignment network reliability genetic algorithms

Slip flow and variable properties of viscoelastic fluid past a stretching surface embedded in a porous medium with heat generation

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Journal of Central South University 2016年第4期23卷 991-999页

作者： ahmed m.megahed Department of mathematics Faculty of Science Benha University (13518)

This study examines theoretically and computationally the non-Newtonian boundary layer flow and heat transfer for a viscoelastic fluid over a stretching continuous sheet embedded in a porous medium with variable fluid properties, slip velocity, and internal heat generation/absorption. The flow in boundary layer is considered to be generated solely by the stretching of the sheet adjacent to porous medium with boundary wall slip condition. Highly nonlinear momentum and thermal boundary layer equations governing the flow and heat transfer are reduced to set of nonlinear ordinary differential equations by appropriate transformation. The resulting ODEs are successfully solved numerically with the help of shooting method. Graphical results are shown for non-dimensional velocities and temperature. The effects of heat generation/absorption parameter, the porous parameter, the viscoelastic parameter, velocity slip parameter, variable thermal conductivity and the Prandtl number on the flow and temperature profiles are presented. moreover, the local skin-friction coefficient and Nusselt number are presented. Comparison of numerical results is made with the earlier published results under limiting cases.

关键词： viscoelastic fluid variable fluid properties slip velocity

Variable fluid properties and variable heat flux effects on the flow and heat transfer in a non-Newtonian maxwell fluid over an unsteady stretching sheet with slip velocity

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Chinese Physics B 2013年第9期22卷 480-485页

作者： ahmed m. megahed Department of mathematics Faculty of ScienceBenha University

The effects of variable fluid properties and variable heat flux on the flow and heat transfer of a non-Newtonian maxwell fluid over an unsteady stretching sheet in the presence of slip velocity have been studied. The governing differential equations are transformed into a set of coupled non-linear ordinary differential equations and then solved with a numerical technique using appropriate boundary conditions for various physical parameters. The numerical solution for the governing non-linear boundary value problem is based on applying the fourth-order Runge-Kutta method coupled with the shooting technique over the entire range of physical parameters. The effects of various parameters like the viscosity parameter, thermal conductivity parameter, unsteadiness parameter, slip velocity parameter, the Deborah number, and the Prandtl number on the flow and temperature profiles as well as on the local skin-friction coefficient and the local Nusselt number are presented and discussed. Comparison of numerical results is made with the earlier published results under limiting cases.

关键词： maxwell fluid unsteady stretching sheet variable fluid properties variable heat flux

Ant Colony Optimization for multi-Objective multicast Routing

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Computers, materials & Continua 2020年第6期63卷 1159-1173页

In the distributed networks,many applications send information from a source node to multiple destination *** support these applications requirements,the paper presents a multi-objective algorithm based on ant colonies to construct a multicast tree for data transmission in a computer *** proposed algorithm simultaneously optimizes total weight(cost,delay and hop)of the multicast *** results prove the proposed algorithm outperforms a recently published multi-objective multicast Algorithm specially designed for solving the multicast routing ***,it is able to find a better solution with fast convergence speed and high reliability.

关键词： multimedia communication multicast routing multicast tree quality of service ant colony

^(199)Sn AND ^(57)Fe mOSSBAUER SPECTROSCOPIC STUDy OF THE mECHANICALLy ALLOyED Fe-Sn ALLOyS

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Acta metallurgica Sinica(English Letters) 1998年第5期11卷 335-341页

作者： y.z.yang y.L.zhu Q.S.Li X.m.ma y.D.Dong y.z.Chuang Guangdong Univ of Technology Guangzhou China

Nanocrystalline supersaturated solid solutions (Sa in Fe) with Sn content less than 50 at. %,and FeSn2 and Fe1.3Sn intermetallic compounds have been prepared by mechanical alloying of Fe and Sn mixture powders with composition of Fe1-xSnx (x≤0.5).The atomic alloying the formation and microstructure, especially the coordination environments, of the resultant alloys have been studied by X-ray diffraction, 57Fe and 119Sn mossbauer Spectroscopy and diffrrential scanning calorimetry. The Fe and Sn coordination environments and the composition dependence of the hyperfine parameters on the Fe and Sn content have been fully discussed with respect to the solid dissolution alloying, grain refinement, and distortion caused or induced by mechanical alloying.

关键词： mechanical alloying mossbauer effect nanocrystalline Fe-Sn alloy

Impacts of environmental factors on urban heating

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Journal of Environmental Sciences 2010年第12期22卷 1903-1909页

作者： Rizwan ahmed memon Dennis y.C.Leung Department of mechanical Engineering Mehran University of Engineering & Technology Department of mechanical Engineering The University of Hong Kong School of Energy and Environment City University of Hong Kong

This study investigated the impact of important environmental variables （i.e., wind speed, solar radiation and cloud cover） on urban heating. meteorological parameters for fifteen years （from 1990 to 2005）, collected at a well developed and densely populated commercial area （Tsim Sha Tsui, Hong Kong）, were analyzed in details. Urban heat island intensity （UHII）, a well known indicator of urban heating, has been determined as the spatially averaged air-temperature difference between Tsim Sha Tsui and Ta Kwu Ling （a thinly populated rural area with lush vegetation）. Results showed that the UHII and cloud cover have increased by around 9.3% and 4%, respectively, whereas the wind speed and solar radiation have decreased by around 24% and 8.5%, respectively. The month of December experienced the highest UHII （10.2℃） but the lowest wind speed （2.6 m/sec） and cloud cover （3.8 oktas）. Conversely, the month of April observed the highest increases in the UHII （over 100%） and the highest decreases in wind speed （over 40 %） over fifteen years. Notably, the increases in the UHII and reductions in the wind speed were the highest during the night-time and early morning. Conversely, the intensity of solar radiation reduced while the intensity of urban cool island （UCII） increased during solar noon-time. Results demonstrated strong negative correlation between the UHII and wind speed （coefficient of determination, R^2 = 0.8） but no negative correlation between UCII and solar radiation attenuation. A possible negative correlation between UHII and cloud cover was investigated but could not be substantiated.

关键词： urban heat island urban cool island wind speed cloud cover

Effect of Al_(2)O_(3)on the mechanical Properties of(B_(4)C+Al_(2)O_(3))/Al Neutron Absorbing materials

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Acta metallurgica Sinica(English Letters) 2024年第8期37卷 1411-1420页

作者： J.X.Cai B.m.Shi N.Li y.Liu z.G.zhang y.N.zan Q.z.Wang B.L.Xiao z.y.ma Shi‑Changxu Innovation Center for Advanced materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory of Nuclear materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of materials Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

B_(4)C/Al composites are widely utilized as neutron absorbing materials for the storage and transportation of spent nuclear *** order to improve the high-temperature mechanical properties of B_(4)C/Al composites,in-situ nano-Al_(2)O_(3)was introduced utilizing oxide on Al powder *** this study,the Al_(2)O_(3)content was adjusted by utilizing spheroid Al powder with varying diameters,thereby investigating the impact of Al_(2)O_(3)content on the tensile properties of(B_(4)C+Al_(2)O_(3))/Al *** was found that the pinning effect of Al_(2)O_(3)on the grain boundaries could hinder the recovery of dislocations and lead to dislocation accumulation at high *** the result,with the increase in Al_(2)O_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al powder used in this investigation had a diameter of 1.4μm,whereas the resultant composite exhibited a maximum strength of 251 mPa at room temperature and 133 mPa at 350℃,surpassing that of traditional B_(4)C/Al composites.

关键词： Al matrix composites Neutron absorbing materials (B_(4)C+Al_(2)O_(3))/Al composites High-temperature strength