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运用灌注CT评估胰腺导管腺癌病人对新辅助化疗和放疗反应的初步经验

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国际医学放射学杂志 2019年第6期 728-728页

作者： a.hamdy Y.Ichikawa Y.Toyomasu M.Nagata N.Nagasawa Y.Nomoto 殷常青 Department of Radiology Mie University Hospital

摘要 CT上肿瘤大小的变化不能可靠地预测新辅助化疗和放疗(CRT)后的治疗反应,且与组织学反应分级的相关性较差。目的探讨应用灌注CT预测胰腺导管腺癌(PDA)对

关键词：胰腺导管腺癌放疗反应 CT 新辅助化疗

Evaluating the inelastic displacement ratios of moment-resisting steel frames designed according to the Egyptian code

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Earthquake Engineering and Engineering Vibration 2019年第1期18卷 159-170页

作者： hamdy Abou-Elfath Structural Engineering Department Faculty of Engineering Alexandria University

Seismic codes estimate the maximum displacements of building structures under the design-basis earthquakes by amplifying the elastic displacements under the reduced seismic design forces with a deflection amplification factor(DAF). The value of DAF is often estimated as ρ× R, where R is the force reduction factor and ρ is the inelastic displacement ratio that accounts for the inelastic action of the structure according to the definition presented by FEMA P695. The purpose of this study is to estimate the ρ-ratio of moment resisting steel frames(MRSFs) designed according to the Egyptian code. This is achieved by conducting a series of elastic and inelastic time-history analyses by two sets of earthquakes on four MRSFs designed according to the Egyptian code and having 2, 4, 8 and 12 stories. The earthquakes are scaled to produce maximum story drift ratios(MSDRs) of 1.0%, 1.5%, 2.0% and 2.5%. The mean values of the ρ-ratio are calculated based on the displacement responses of the investigated frames. The results obtained in this study indicate that the consideration of ρ for both the roof drift ratios(RDRs) and the MSDRs equal to 1.0 is a reasonable estimation for MRSFs designed according to the Egyptian code.

关键词： steel frame story drift inelastic analysis earthquake deflection amplification factor

State Observer Based Dynamic Fuzzy Logic System for a Class of SISO Nonlinear Systems

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International Journal of Automation and computing 2013年第2期10卷 118-124页

作者： Mohamed hamdy Department of Industrial Electronics and Control Engineering Faculty of Electronic Engineering Menofia University

This paper presents an observer based dynamic fuzzy logic system （DFLS） scheme for a class of unknown single-input single-output （SISO） nonlinear dynamic systems with external disturbances. The proposed approach does not need the availability of the state variables. Within this scheme, the DFLS is employed to identify the unknown nonlinear dynamic system. The control law and parameter adaptation laws of the DFLS are derived based on Lyapunov synthesis approach. The control law is robustfied in H∞ sense to attenuate external disturbance, model uncertainties, and fuzzy approximation errors. It is shown that under appropriate assumptions, it guarantees the boundedness of all the signals in the closed-loop system and the asymptotic convergence to zero of tracking errors. The proposed method is applied to an inverted pendulum system to verify the effectiveness of the proposed algorithms.

关键词： Single-input single-output (SISO) nonlinear system dynamic fuzzy logic system (DFLS) observer Lyapunov synthesis approach stability analysis.

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

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

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.

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