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Inelastic displacement ratio of low-to mid-rise BRBFs designed under variable levels of seismicity

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Earthquake Engineering and Engineering Vibration 2023年第3期22卷 763-775页

作者： hamdy Abou-Elfath Mostafa Ramadan Faculty of Engineering Alexandria UniversityAlexandria 21544Egypt

Buckling-restrained braces(BRBs)have shown their capability to provide building structures with stiffness,strength,and *** the seismic drifts of buckling-restrained braced frames(BRBFs)is an important design step to control structural and non-structural *** current practice of seismic design,the estimation of seismic drifts of BRBFs is performed by using empirical calculations that are independent upon either the type of the structural system or the design level of *** these empirical calculations,the seismic drifts are estimated by amplifying the reduced elastic drifts obtained under design lateral loading with a displacement amplification factor(DAF).The value of DAF is considered equal to the product of the response modification factor R and the inelastic displacement ratioρ.The goal of the current research is to assess the value ofρfor low-to mid-rise BRBFs designed under low and high levels of *** goal has been achieved by conducting a series of elastic and inelastic time-history analyses pertaining to an ensemble of earthquake records on 3-,6-and 9-story *** results indicate that theρ-ratio increases with an increase in design seismic intensity and an increase in experienced *** range ofρfor low seismicity designs ranges from 0.63 to 0.9,while for high seismicity designs this range stretches from 0.83 to *** has been found that the consideration of a generalρ-ratio of 1.0 is a reasonable estimation for the design of the BRBFs considered in this study.

关键词： displacement amplification factor inelastic displacement ratio seismicity buckling-restrained brace seismic drift seismic design

Theoretical-period characteristics of frame buildings designed under variable levels of seismicity and allowable-drift

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Earthquake Engineering and Engineering Vibration 2020年第3期19卷 669-681页

作者： hamdy Abou-Elfath Emad Elhout Structural Engineering Department Faculty of EngineeringAlexandria UniversityAlexandria 21544Egypt Higher Institute of Engineering and Technology King-MarriottAlexandriaEgypt

Period equations provided by seismic codes are generally derived by calibration with recorded period data of buildings located in high seismicity *** period-equations do not account for either the design level of seismicity or the permissible limit of lateral *** designed under high level of seismicity are expected to display higher stiffness and shorter periods than buildings designed under low-to-medium seismicity *** addition,buildings designed with high level of permissible lateral-drift are expected to display lower stiffness and longer periods than buildings designed with low level of permissible *** this study,the theoretical fundamental-periods of an ensemble of regular reinforced concrete(RC)and steel moment-resisting frame(MRF)buildings having 3-,6-,9-and 12-stories and designed with various levels of seismicity and permissible lateral-drift are *** obtained outcome indicates the sensitivity of the MRF theoretical-periods to the design seismicity and the permissible *** results also indicate the need for modifying the current period equations to realistically account for the variations in the design seismicity and allowable lateral-drift of MRF buildings.

关键词： concrete frame stiffness

Partially Deep-Learning Encryption Technique

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Computers, Materials & Continua 2023年第2期74卷 4277-4291页

作者： hamdy M.Mousa Faculty of Computers and Information Menoufia UniversityMenoufia32511Egypt

The biggest problem facing the world is information security in the digital *** protection and integrity are hot topics at all times,so many techniques have been introduced to transmit and store data *** increase in computing power is increasing the number of security breaches and attacks at a higher rate than before on ***,a number of existing security systems are at risk of *** paper proposes an encryption technique called Partial Deep-Learning Encryption Technique(PD-LET)to achieve data ***-LET includes several stages for encoding and decoding digital *** preprocessing,convolution layer of standard deep learning algorithm,zigzag transformation,image partitioning,and encryption key are the main stages of ***,the proposed technique converts digital data into the corresponding matrix and then applies encryption stages to *** implementation of encrypting stages is frequently *** collaboration between deep learning and zigzag transformation techniques provides the best output result and transfers the original data into a completely undefined image which makes the proposed technique efficient and secure via data ***,its implementation phases are continuously changed during the encryption phase,which makes the data encryption technique more immune to some future attacks because breaking this technique needs to know all the information about the encryption *** security analysis of the obtained results shows that it is computationally impractical to break the proposed technique due to the large size and diversity of keys and PD-LET has achieved a reliable security system.

关键词： Encryption technique deep learning security zigzag transformation image partitioning

DEPENDENCE OF MODULUS OF ELASTICITY AND THERMAL CONDUCTIVITY ON REFERENCE TEMPERATURE IN GENERALIZED THERMOELASTICITY FOR AN INFINITE MATERIAL WITH A SPHERICAL CAVITY

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Applied Mathematics and Mechanics(English Edition) 2005年第4期26卷 470-475页

作者： hamdy M.Youssef Mathematical Department Faculty of Engineering Umm Al_Qura UniversityMakkah Al_Mokaramah P.5555 Saudi Arabia

The equations of generalized thermoelasticity with one relaxation time with variable modulus of elasticity and the thermal conductivity were used to solve a problem of an infinite material with a spherical *** inner surface of the cavity was taken to be traction free and acted upon by a thermal shock to the surface. Laplace transforms techniques were used to obtain the solution by a direct *** inverse Laplace transforms was obtained *** temperature,displacement and stress distributions are represented graphically.

关键词： thermoelasticity generalized thermoelasticity modulus of elasticity thermal conductivity

Purang Ultramafic Complex and Their Geological Origin, Southwest Tibet

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Acta Geologica Sinica(English Edition) 2015年第A02期89卷 22-24页

作者： Hamed Gamal El Dien Mohamed hamdy abdel Salam Abu EI-Ela Adel Hassan Youngwoo Kil Geology Department FaculW of Science Tanta University 31527 Tanta Egypt Department of earth sciences school of natural science kanazawa university Japan Department of Energy and Resources Engineering College of Engineering Chonnam National University Yongbong-roBuk-gu Gwangju Korea

Neoproterozoic ophiolitic Serpentinites are common in the Arabian-Nubian Shield （ANS） of the Eastern Desert （ED） of Egypt, which were formed in arc stage in different tectonic setting. Thus they might subject to exchange with the crustal material derived from recycling subducting oceanic lithosphere. This caused metasomatism enriching the rocks in incompatible elements and forming non- residual minerals. Herein,

关键词： OPHIOLITES RESEARCH SERPENTINITE METASOMATISM (Mineralogy) RARE earths EARTH'S mantle

Comparative Study of Different Decoupling Schemes for TITO Binary Distillation Column via PI Controller

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IEEE/CAA Journal of Automatica Sinica 2018年第4期5卷 869-877页

作者： Mohamed hamdy Abdalhady Ramadan Belal Abozalam Industrial Electronics and Control Engineering Department Faculty of Electronic EngineeringMenoufia UniversityMenouf-23952Egypt Badr Petroleum Company(BAPETCO) CairoEgypt

This paper presents a comparative study of different decoupling control schemes for a two-input, two-output(TITO) binary distillation column via proportional-integral(PI)controller. The key idea behind this paper is designing two novel fuzzy decoupling schemes that depend on human knowledge,instead of the system mathematical model used in conventional decoupling schemes. Based on conventional and inverted decoupling schemes, fuzzy and inverted fuzzy decoupling schemes are developed. The control effect is compared using simulation results for the proposed two schemes with conventional decoupling and inverted decoupling. The proposed fuzzy decoupling schemes are easy to realize and simple to design, besides they have a good decoupling capability. Two methods are used to prove asymptotic stability of each loop and the entire closed-loop system by applying the proposed fuzzy decoupling-based PI *** Wood and Berry model of a binary distillation column is used to illustrate the applicability of the proposed schemes.

关键词： Binary distillation column conventional decoupling fuzzy decoupling proportional-integral(PI) controller stability analysis

Observer-based Adaptive Fuzzy Control for a Class of Nonlinear Time-delay Systems

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International Journal of Automation and computing 2013年第4期10卷 275-280页

作者： Hassan A. Yousef Mohamed hamdy Department of Electrical and Computer Engineering College of Engineering Sultan Qaboos University Department of Industrial Electronics and Control Engineering Faculty of Electronic Engineering Menofia University

An observer-based adaptive fuzzy control is presented for a class of nonlinear systems with unknown time delays. The state observer is first designed, and then the controller is designed via the adaptive fuzzy control method based on the observed states. Both the designed observer and controller are independent of time delays. Using an appropriate Lyapunov-Krasovskii functional, the uncertainty of the unknown time delay is compensated, and then the fuzzy logic system in Mamdani type is utilized to approximate the unknown nonlinear functions. Based on the Lyapunov stability theory, the constructed observer-based controller and the closed-loop system are proved to be asymptotically stable. The designed control law is independent of the time delays and has a simple form with only one adaptive parameter vector, which is to be updated on-line. Simulation results are presented to demonstrate the effectiveness of the proposed approach.

关键词： Observer adaptive fuzzy control nonlinear systems time delay stability.

Microstructure, Corrosion, and Fatigue Properties of Alumina-Titania Nanostructured Coatings

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Journal of Surface Engineered Materials and Advanced Technology 2011年第3期1卷 101-106页

作者： Ahmed Ibrahim abdel Salam hamdy 不详

Air Plasma spray process was used to deposit a conventional and nanostructured Al2O3-13 wt% TiO2 coatings on a stainless steel substrates. Morphology of the powder particles, microstructure and phase composition of the coatings were characterized by XRD and SEM. Potentiodynamic polarization tests and Electrochemical Impedance Spectro- scopy (EIS) were used to analyze the corrosion of the coated substrate in 3.5% NaCl solutions to determine the opti-mum conditions for corrosion protection. The fatigue strength and hardness of the coatings were investigated. The experimental data indicated that the nanostructured coated samples exhibited higher hardness and fatigue strength compared to the conventional coated samples. On the other hand, the conventional coatings showed a better localized corrosion resistance than the nanostructured coatings.

关键词： Nanostructured Coatings Alumina-Tiania Fatigue Strength Corrosion Resistance

Corrosion and corrosion-fatigue behavior of magnesium metal matrix composites for bio-implant applications:A review

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Journal of Magnesium and Alloys 2023年第4期11卷 1125-1161页

作者： Hassan Delavar Amirhossein Jabbari Mostahsan hamdy Ibrahim School of Mechanical Engineering Iran University of Science and TechnologyTehranIran Department of Mechanical Engineering Sharif University of TechnologyTehranIran Mechanical Engineering Department University of Tennessee at ChattanoogaChattanoogaTN 37403USA

Recently,the topic of bioresorbable metals,with much focus on magnesium for bone implant applications,has been an area of considerable ***,it could be argued that magnesium is the most promising biodegradable material currently being studied for use as an orthopedic skeletal fixation and joint replacement ***,the fast degradation rate of magnesium-based materials in the physiological environment negatively affects their mechanical integrity and hence limits their biomedical *** most critical conditions may occur when the implant is subjected to a corrosive physiological environment and a fluctuating load during daily ***,numerous studies have been published on the synthesis,alloying,and coating of magnesium to control degradation rate and increase strength and *** the materials and strategies employed to achieve these goals,magnesium-based biocomposites have exhibited superior mechanical properties and acceptable ***,there is a lack of understanding of their corrosion and corrosion-fatigue *** understanding is necessary to qualify these new materials for various bio-implant *** this end,this paper reviews the recent advances in the corrosion and corrosion-fatigue behavior of magnesium-based *** also provides a comprehensive discussion of different factors that influence the biocompatibility,corrosion,fatigue,and corrosion-fatigue of magnesium-based biocomposites as potential implant *** study emphasizes that despite the abundance of various studies on the corrosion behavior of magnesium-based biocomposites,there is an imperative need for more fatigue and corrosion-fatigue studies.

关键词： Magnesium biocomposites Biodegradable implants Corrosion Fatigue Corrosion-fatigue