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Inconsistence of Non-Singular Spherically Symmetric Solution and a Satisfactory Energy-Momentum Complex

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Communications in Theoretical Physics 2010年第10期54卷 625-629页

作者： gamal G.L.Nashed Mathematics Department Faculty of ScienceAin Shams University

Two spherically symmetric non-singular black hole solutions in Moiler tetrad theory of gravitation have been obtained. Although the two solutions have the same form of metric （spherically symmetric nonsingular black hole）, their energy contents are different. We use another method given by Gibbons and Hawking to calculate the energy content of these solutions. We also obtained different value of energy. Study the requirements of a satisfactory energymomentum complex given by Moiler we find that the second solution, which behaves as 1/√r, is not transformed as a four-vector under Lorentz transformation.

关键词： non-singular black hole solutions energy using Moiler complex energy using Gibbons and Hawking method Lorentz transformatio

Double compound combination synchronization among eight n-dimensional chaotic systems

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Chinese Physics B 2018年第8期27卷 150-158页

作者： gamal M Mahmoud Tarek M Abed-Elhameed Ahmed A Farghaly Department of Mathematics Faculty of Science Assiut University

Depending on double compound synchronization and compound combination synchronization, a new kind of syn- chronization is introduced which is the double compound combination synchronization （DCCS） of eight n-dimensional chaotic systems. This kind may be considered as a generalization of many types of synchronization. In the communica- tion, based on many of drive and response systems, the transmitted and received signals will be more secure. Using the Lyapunov stability theory and nonlinear feedback control, analytical formulas of control functions are obtained to insure our results. The corresponding analytical expression and numerical treatment are used to show the validity and feasibility of our proposed synchronization scheme. The eight memristor-based Chua oscillators are considered as an example. Other examples can be similarly investigated. The proposed synchronization technique is supported using the MATLAB simula- tion outcomes. We obtain the same results of numerical treatment of our synchronization using simulation observations of our example.

关键词： double compound synchronization compound combination synchronization chaotic system Lya-punov stability

Electronic Properties of Red P-Type Tl2S5 Single Crystals

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Chinese Physics Letters 2005年第6期22卷 1530-1532页

作者： G.A.gamal M.AbouZied A.A.Ebnalwaled DepartmentofPhysics FacultyofScienceSouthValleyUniversityQena83511Egypt

Single crystals of red Tl2S5 were prepared by a special modified vertical Bridgman and Stockbarger technique. This growth was performed in our laboratory. The influences of temperature on the electrical conductivity, Hall mobility, carrier concentration, and thermoelectric power (TEP) were carried out in the temperature range 277–413K. Throughout these measurements, various physical parameters such as effective mass of charge carriers, carrier mobility, diffusion coefficient, and the relaxation time for both majority and minority carriers were found.

关键词： TI USA K

Video Identification Based on Watermarking Schemes and Visual Cryptography

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Computer Systems Science & Engineering 2022年第2期40卷 441-453页

作者： Maged Wafy Samr gamal Zanaty Mahmoud Elkhouly Department of Information Technology Computers and Artificial Intelligence Helwan UniversityCairoEgypt Department of Information Technology Computing Studies Arab Open UniversityCairoEgypt Department of Information Technology Information Technology and Computer Science Sinai UniversityIsmailiaEgypt

Related to the growth of data sharing on the Internet and the wide-spread use of digital media,multimedia security and copyright protection have become of broad *** cryptography(VC)is a method of sharing a secret image between a group of participants,where certain groups of participants are defined as qualified and may combine their share of the image to obtain the original,and certain other groups are defined as prohibited,and even if they combine knowledge of their parts,they can’t obtain any information on the secret *** visual cryptography is one of the techniques which used to transmit the secrete image under the cover *** vision systems are connected to visual *** black and white image was originally used as a hidden *** order to achieve the owner’s copy right security based on visual cryptography,a watermarking algorithm is *** suggest an approach in this paper to hide multiple images in video by meaningful shares using one binary *** a common share,which we refer to as a smart key,we can decrypt several images *** on a given share,the smart key decrypts several hidden *** smart key is printed on transparency and the shares are involved in video and decryption is performed by physically superimposing the transparency on the *** binary,grayscale,and color images,we test the proposed method.

关键词： Visual cryptography(VC) video watermarking PSNR

A new systematic firefly algorithm for forecasting the durability of reinforced recycled aggregate concrete

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Frontiers of Structural and Civil Engineering 2022年第3期16卷 329-346页

作者： Wafaa Mohamed SHABAN Khalid ELBAZ Mohamed AMIN Ayat gamal ASHOUR Department of Civil and Environmental Engineering College of EngineeringShantou UniversityShantou 515063China Department of Civil Engineering Misr Higher Institute of Engineering and TechnologyMansouraEgypt Department of Civil Engineering Higher Future Institute of Engineering and TechnologyMansouraEgypt Guangdong Engineering Center for Structure Safety and Health Monitoring Shantou UniversityShantou 515063China Civil and Architectural Construction Department Faculty of Technology and EducationSuez UniversityIsmailiaEgypt Department of Civil and Environmental Engineering Collage of EngineeringUniversity of SharjahSharjah 27272UAE

This study presents a new systematic algorithm to optimize the durability of reinforced recycled aggregate *** proposed algorithm integrates machine learning with a new version of the firefly algorithm called chaotic based firefly algorithm(CFA)to evolve a rational and efficient predictive *** CFA optimizer is augmented with chaotic maps and Levy flight to improve the firefly performance in forecasting the chloride penetrability of strengthened recycled aggregate concrete(RAC).A comprehensive and credible database of distinctive chloride migration coefficient results is used to establish the developed algorithm.A dataset composite of nine effective parameters,including concrete components and fundamental characteristics of recycled aggregate(RA),is used as input to predict the migration coefficient of strengthened RAC as output,k-fold cross validation algorithm is utilized to validate the hybrid *** numerical benchmark analyses are applied to prove the superiority and applicability of the CFA algorithm in predicting chloride *** show that the developed CFA approach significantly outperforms the firefly algorithm on almost tested functions and demonstrates powerful *** addition,the proposed strategy can be an active tool to recognize the contradictions in the experimental results and can be especially beneficial for assessing the chloride resistance of RAC.

关键词： chloride penetrability recycled aggregate concrete machine learning concrete components durability

Non-alcoholic steatohepatitis or metabolic-associated fatty liver:time to change

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Hepatobiliary Surgery and Nutrition 2021年第1期10卷 123-125页

作者： gamal Shiha Nasser Mousa Egyptian Liver Research Institute and Hospital(ELRIAH) MansouraEgypt Hepatology and Gastroenterology Unit Internal Medicine Department Tropical Medicine Department Faculty of MedicineMansoura UniversityMansouraEgypt

Non-alcoholic fatty liver disease(NAFLD)is a range of liver disease characterized by the occurrence of steatosis in greater than 5%of hepatocytes of people who drink tiny or no *** comprises,a benign non-alcoholic fatty liver(NAFL),and the more serious non-alcoholic steatohepatitis(NASH)described by steatosis,hepatocellular ballooning,lobular inflammation and lastly cirrhosis(1).

关键词： balloon NAFLD liver

A NEW CONCEPT AND EXHIBITION PROGRAM FOR THE EGYPTIAN MUSEUM IN CAIRO

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Journal of Ancient Civilizations 2018年第1期33卷 41-82页

作者： Mohamed gamal ras.ed Damietta University

1. IntroductionIn parallel to the ongoing plans and anticipated opening of the Grand Egyptian Museum （GEM） and the National Museum of Egyptian Civilization （NMEC）,1 the Egyptian Museum in Cairo （EMC） will need t... 详细信息

关键词：国家博物馆埃及开罗展览

Iron Biomineralization Controls on Geophysical Signatures of Hydrocarbon Contaminated Sediments

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Journal of Earth Science 2015年第6期26卷 835-843页

作者： Estella A.Atekwana gamal Z.Abdel Aal Boone Pickens School of Geology Oklahoma State University Geology Department Faculty of Science Assiut University

The interpretation of geophysical data from mature hydrocarbon contaminated sites has relied on a conductive plume model where the conductivity of the subsurface contaminant volume is the result of microbial mediated changes in pore fluid chemistry. This conductive anomalous region is characterized by high total dissolved solids and occurs within the water table fluctuation zone where microbial activity is the maximum. Here we update this conductive plume model by providing new insights from recent laboratory investigations and geophysical data from hydrocarbon contaminated sites suggesting the unrecognized role of the impact that microbial-mediated metallic mineral precipitates have on geophysical signatures. We show that microbial redox processes（e.g., iron and sulfate reduction） during the biodegradation process involve mineralogical transformations and the precipitation of new minerals（e.g., magnetite, and pyrite） that can impact the electrical and magnetic properties of contaminated sediments. We provide examples from laboratory experiments and field studies and suggest that knowledge of the dominant redox processes occurring at hydrocarbon contaminated sites and the mineral phases formed is critical for a more robust interpretation of geophysical data associated with microbial-mediated changes at hydrocarbon contaminated sites. We also show that integration of both magnetic and electrical techniques may help reduce ambiguity in data interpretation.

关键词： hydrocarbon redox processes magnetic susceptibility bioremediation conductivity.

Contemporary construction in historical sites:The missing factors

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Frontiers of Architectural Research 2024年第3期13卷 487-504页

作者： Sina Kamali Tabrizi Mohamed gamal Abdelmonem School of Architecture Design and the Built EnvironmentNottingham Trent UniversityNottinghamUK Department of Architecture and the Built Environment University of YorkYorkUK

Historical sites(HSs)are akin to living entities,and their existence is perpetuated through the erection of new buildings or *** HSs need sustainable development and new construction,as existing monuments fail to meet contemporary user *** the urgent demand,many new buildings within HSs have been constructed without considering the influencing factors on contextual value,built,and natural *** oversight has led to irreversible damage to their historical *** studies have independently explored interventions,construction,and development within ***,there is a conspicuous absence of comprehensive research that concurrently addresses these issues while preserving the intrinsic value of the *** study aims to identify the variables and factors contributing to the successful design and construction of new buildings within HSs,satisfying user needs,conserving contextual values,and achieving sustainability with the natural and built *** research employs a mixed-method approach,gathering raw data through literature reviews,case studies,and expert *** study population comprised 97 experts in architectural heritage conservation and sustainable *** factor analysis was utilized for data analysis,leading to the identification of influential *** study highlights the significance of the location,function,scale,form,material,skyline,viewpoint,accessibility,reversibility,topography,sustainability,technology,structural system,lifespan,and interior design in constructing new buildings within a ***,the design of new additions should adhere to five guiding principles:integrated design,volume design,green design,compatible design,and modern *** this context,the new structures will fulfill user needs,preserve or enhance contextual values,and harmonize with the built and natural environment.

关键词： New building Contemporary construction Historical sites Sustainable development Architectural heritage