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Insights into the adsorption performance and mechanism of Cr(Ⅵ)onto porous nanocomposite prepared from gossans and modified coal interface:Steric,energetic,and thermodynamic parameters interpretations

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Chinese Journal of Chemical Engineering 2023年第9期61卷 118-128页

作者： Mohamed Mobarak Saleh Qaysi Mohamed Saad Ahmed Yasser F.Salama Ahmed Mohamed Abbass Mohamed Abd Elrahman hamdy aabdel-gawwad Moaaz K.Seliem Physics Department Faculty of ScienceBeni-Suef UniversityEgypt Geology and Geophysics Department College of ScienceKing Saud University11451 RiyadhSaudi Arabia Geology Department Faculty of ScienceBeni-Suef UniversityEgypt Department of Building Materials and Construction ChemistryInstitute of Civil EngineeringTechnische Universitat BerlinBerlinGermany Structural Engineering Department Faculty of EngineeringMansoura UniversityMansouraEgypt Raw Building Materials and Processing Technology Research Institute Housing and Building National Research Center(HBRC)CairoEgypt Faculty of Earth Science Beni–Suef UniversityEgypt

Herein,iron oxide/hydroxides deposits(gossans)were utilized,for the first time,in the fabrication of magnetite nanoparticles(MNPs)to load modified coal(MC).The as-synthesized MNPs@MC composite was characterized via different techniques and utilized for the Cr(Ⅵ)*** studies supported by theoretical treatment were applied to offer a new overview of the Cr(Ⅵ)adsorption geometry and mechanism at 25-45℃.Experimental results suggested that the Cr(Ⅵ)uptake was mainly governed by adsorption-reduction coupled *** Langmuir model fitted well the Cr(Ⅵ)adsorption data with maximum adsorption capacities extended from 115.24 to 129.63 mg·g^(-1).Theoretical calculations indicated that Cr(Ⅵ)ions were adsorbed on the MNPs@MC following the theory of the advanced monolayer statistical *** number of ions removed per site ranged from 1.88 to1.23 suggesting the involvement of vertical geometry and multi-ionic mechanism at all *** increment of the active sites density and the adsorption capacity at saturation with improving temperature reflected an endothermic ***,the Cr(Ⅵ)adsorption was controlled by physical forces as the adsorption energies were less than 40 kJ·mol^(-1).The calculated free enthalpy,*** internal energy explained the spontaneous nature and the viability of Cr(Ⅵ)adsorption on the MNPs@MC *** results offer a new approach in utilizing the iron-rich deposits as gossans in the preparation of magnetic and low-cost adsorbents for wastewater remediation.

关键词： Coal Magnetic nanoparticles Cr(Ⅵ)adsorption Statistical models Thermodynamic parameters

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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

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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.

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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

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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

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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

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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

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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.

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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

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Squamous cell carcinoma metastatic to cervical lymph nodes from unknown primary origin:the impact of chemoradiotherapy

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Chinese Journal of Cancer 2012年第10期31卷 484-490页

作者： Hany Eldeeb Rasha hamdy Hamed Oncology Center Northampton General HospitalNorthampton NN1 5BDUK Department of clinical Oncology and Nuclear Medicine Faculty of MedicineMansoura UniversityEgypt

The management of cervical lymph node metastases of squamous cell carcinoma from an unknown primary site is still a therapeutic *** report here our experience in treating these patients with chemoradiotherapy as a curative *** from 40 patients were *** total,20(50%) patients underwent excisional *** patients underwent radiotherapy,which was delivered to both sides of the neck and pharyngeal mucosa(extensive field),and concurrent chemotherapy consisting of weekly cisplatin at a dose of 40 mg/*** clinical stage of the cervical nodes at presentation was N1 in 25%,N2 in 60%,and N3 in 15%.Most patients(75%) developed at least grade 3 *** patients(20%) had grade 3 xerostomia and 18 patients(45%) required esophageal dilation for *** 5-year overall survival(OS) rate of all patients was 67.5%.The 5-year OS rates of patients with N1,N2,and N3 lesions were 100%,67%,and 41%,respectively(P = 0.046).The 5-year progression-free survival rate was 62.5%.In multivariate analysis,only N stage significantly affected OS(P = 0.022).Emergence of the occult primary was very limited(1 patient only).Our results suggest that extensive irradiation of both sides of the neck and pharyngeal mucosa with concurrent chemotherapy results in a lower emergence of primary *** the survival of patients with unknown primary is comparable to that of patients with known primary,an attempt at cure should always be made.

关键词：鳞状细胞癌淋巴结化疗放射治疗多变量分析生存率患者隐匿性

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