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Design and evaluation of PV-wind hybrid system with hydroelectric pumped storage on the National Power System of Egypt

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Global Energy Interconnection 2018年第3期1卷 301-311页

作者： hamdy m.sultan Ahmed A.Zaki Diab Kuznetsov Oleg N. Zubkova Irina S. National Research University “moscow Power Institute” Department of Electrical Engineering Minia University

National and international policies encourage increased penetration of solar and wind energy into electrical networks in order to reduce greenhouse gas emission. Solar radiation and wind speed variations complicate the integration of wind and solar generation into power systems and delay the transition of these sources from centralized to distributed energy sources. The increased penetration of nontraditional energy sources into the electric grid stimulates the demand for large capacities in the field of energy storage. A mathematical model, which describes the operation of a proposed hybrid system, including solar PV, wind energy, and a pumped storage hydroelectric power plant is developed in this paper. This hydropower plant utilizes seawater as a lower reservoir, and only a tank has to be built in order to reduce the installation cost of the storing system. The pumped storage power plant used for compensation of the variation of the output energy from the PV and wind power plants by discharging water from the upper reservoir, which is previously pumped in the case of surplus energy from PV and wind turbine power plants. The impact of the proposed system on the grid utility is investigated in accordance with the values of energy exchange(deficits and surpluses of energy) between the considered hybrid system and the grid. The optimum design is determined by the pump and turbine capacities, upper reservoir volume, and the volume of water left in the tank for emergencies. Different scenarios of the optimum operations are presented for analysis. The results obtained from the examined scenarios indicate the ability of such a hybrid energy system to reduce the exchange of energy with the grid. This paper indicates the technical feasibility of seawater pumpedstorage hydropower plant for increasing the Egyptian national grid’s ability to accept high integration of renewable energy sources.

关键词： Digital controllers LCL filter Time delay Grid-connected converters Virtual Resistor Real Resistor VOC Grid impedance variation Controllers design

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Retracing Realistic Disaster Scenarios from Archival Sources:A Key Tool for Disaster Risk Reduction

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International Journal of Disaster Risk Science 2021年第5期12卷 635-648页

作者： Bashir Ahmad Akhtar Alam m.sultan Bhat Khurshid Ahmad Bhat Jeelani Inaam ul Haq Hakim Farooq Ahmad Junaid Qadir Department of Geology Nawakadal SchoolSrinagar 190002India Institute for Risk and Disaster Reduction University College LondonWCIE 6BTUK Department of Geography and Regional Development University of KashmirSrinagar 190006India Department of Statistics Chanapora SchoolSrinagar 190015India Department of Geology Aligarh Muslim UniversityAligarh 202002India

Disaster scenarios are constructed by integrating natural hazard phenomena and social science sources of *** profiled 51 natural hazard events of nineteenth century Kashmir that provide insights into the impacts of varying degree of severity that spread through the socioeconomic and political systems,influenced adaptation,and increased the consequences of the resulting *** root cause of these disasters was embedded in the social,natural,and political economic systems of their time,where vulnerabilities overlapped and interacted periodically with successive colonial regimes and acted as tipping *** combined effect of successive colonial regimes,inept administration,rigid political economy,and natural hazards made the situation go from bad to worse and reduced Kashmir to the depths of distress and *** the arc of the nineteenth century,a series of disasters led the Kashmiri population to learn how to live with disasters and minimize risk,bringing about the evolution of social and environmental *** the natural hazard vulnerability of the Kashmir Valley through archival narratives can help in scenario building to translate findings into formats that reduce related risk now as it did *** resulting information can be useful for regional design,planning,and policy responses to promote disaster risk reduction.

关键词： Disaster risk reduction Historical disasters Kashmir Nineteenth-century disasters Socioeconomic vulnerability

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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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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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On null Controllability of fractional stochastic differential system with fractional Brownian motion

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Journal of Control and Decision 2021年第1期8卷 50-63页

作者： hamdy m.Ahmed Higher Institute of Engineering El-Shorouk AcademyEl-Shorouk CityCairoEgypt

In this paper,we are dealing with the null controllability of fractional stochastic differential system with fractional Brownian *** null controllability for Sobolev-type Hilfer fractional stochastic differential system with fractional Brownian motion of Clarke’s subdifferential type is *** sufficient conditions for null controllability of fractional stochastic differential system with fractional Brownian motion and control on the boundary are ***,an example is given to illustrate the obtained results.

关键词： Fractional Brownian motion Clarke subdifferential fractional stochastic differential system null controllability

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Hilfer fractional neutral stochastic partial differential equations with delay driven by Rosenblatt process

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Journal of Control and Decision 2022年第2期9卷 226-243页

作者： hamdy m.Ahmed Higher Institute of Engineering El-Shorouk AcademyEI-Shorouk CityCairoEgypt

This manuscript is mainly focusing on the approximate controllability and the null controllability for fractional neutral stochastic partial differential equations with delay driven by Rosenblatt *** discuss the sufficient conditions for approximate controllability and null controllability for Hilfer fractional neutral stochastic partial differential equations driven by Rosenblatt ***,we provide two examples to verify the obtained results.

关键词： Hilfer fractional neutral stochastic integro-differential systems approximate controllability null controllability Rosenblatt process

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Is fluoroscopy-free single-use flexible ureteroscopy a feasible treatment for kidney stones with abnormal renal anatomy?

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Asian Journal of Urology 2024年第4期11卷 591-595页

作者： hamdy Aboutaleb mohamed sultan Ahmed Zaghloul Yasser Farahat maher Gawish Fouad Zanaty Urology Department Menoufia University HospitalEgypt Urology Department Burjeel HospitalAbu DhabiUnited Arab Emirates Urology Department AlAzhar UniversityAssiut BranchEgypt

ObjectiveThis study aimed to evaluate the feasibility of the fluoroscopy-free single-use flexible ureteroscopy procedure in the treatment of kidney stones with abnormal renal anatomy compared to normal renal *** patients with abnormal (Group A) and 80 patients with normal (Group B) renal anatomy who had 10–20 mm renal stones were included. They were treated with LithoVue single-use flexible ureteroscopy (Boston Scientific, marlborough, mA, USA) after ureteric dilatation by two different size semi-rigid ureteroscopes. This technique was chosen as the aim was to exclude any ureteric pathology (e.g., stone or stricture), confirm the placement of a safe guidewire, avoid balloon dilatation of the ureter, and achieve safe insertion of a 12 Fr, 35/45 cm ureteric access sheath with optical and tactile sign and without fluoroscopy image for *** mean ages were 43 years and 45 years in Group A and Group B, respectively. The mean stone burden was 14.62 (standard deviation: 5.35) mm^(3) and 14.79 (standard deviation: 4.58) mm^(3) in Group A and Group B, respectively. There is no significant difference between both groups according to the mean operative time, hospital stay, or stone-free rate. The stone-free rate was about 93% in both groups when the stone size was between 10 mm and 15 mm, and less than 54% when the stone size was more than 15 mm to 20 mm. In the majority of cases (80.0% in Group A and 92.5% in Group B), we completed the procedure without fluoroscopy. The perioperative complication rates were comparable in the two ***-free single-use flexible ureteroscopy, when performed by expert urologists, is a feasible treatment for pre-stented patients with kidney calculi of ≤15 mm with abnormal renal anatomy.

关键词： Fluoroscopy Flexible ureteroscopy Renal stone Abnormal renal anatomy

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State-space approach to vibration of gold nano-beam induced by ramp type heating

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Nano-micro Letters 2010年第3期2卷 139-147页

作者： hamdy m.Youssef Khaled A.Elsibai mathematical Department-Faculty of Education-Alexandria University-Egypt mathematics Department Faculty of ScienceMansoura University

In the nanoscale beam,two effects become *** is the non-Fourier effect in heat conduction and the other is the coupling effect between temperature and strain *** the present study,a generalized solution for the generalized thermoelastic vibration of gold nano-beam resonator induced by ramp type heating is *** solution takes into account the above two ***-space and Laplace transform methods are used to determine the lateral vibration,the temperature,the displacement,the stress and the strain energy of the *** effects of the relaxation time and the ramping time parameters have been studied.

关键词： Thermoelasticity Euler-Bernoulli equation Gold nano-beam Ramp type heating

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Interstitial cells of Cajal, the maestro in health and disease

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World Journal of Gastroenterology 2010年第26期16卷 3239-3248页

作者： Randa m mostafa Yasser m moustafa Hosam hamdy Department of Basic medical Sciences College of Medicine Sharjah University Sharjah 27272 United Arab Emirates Department of Pharmacology and Toxicology College of Pharmacy Suez Canal University Ismaelia 24421 Egypt Department of Surgery Vice Chancellor of Medical and Health sciences Colleges Sharjah University Sharjah 27272 United Arab Emirates

Interstitial cells of Cajal (ICC) are important players in the symphony of gut motility. They have a very signif icant physiological role orchestrating the normal peristaltic activity of the digestive system. They are the pacemaker cells in gastrointestinal (GI) muscles. Absence, reduction in number or altered integrity of the ICC network may have a dramatic effect on GI system motility. more understanding of ICC physiology will foster advances in physiology of gut motility which will help in a future breakthrough in the pharmacological interventions to restore normal motor function of GI tract. This mini review describes what is known about the physiologic function and role of ICCs in GI system motility and in a variety of GI system motility disorders.

关键词： Interstitial cells of Cajal Gastrointestinal motility Peristalsis

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Dissolution mechanism and kinetics ofβ(mg_(17)Al_(12))phases in AZ91 magnesium alloy

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Journal of magnesium and Alloys 2024年第4期12卷 1581-1592页

作者： sultan Alomairy Department of Physics College of ScienceTaif UniversityTaif 21944Saudi Arabia

In this study,the phase transformations,crystallization kinetics and dissolution mechanism ofβphase(mg_(17)Al_(12))in magnesium alloy AZ91 were investigated by optical microscopy,X-ray diffraction,differential scanning calorimetry and differential *** results indicate that this AZ91 alloy undergoes a phase transformation during aging,a discontinuous precipitation of theβphase(mg_(17)Al_(12))at 150℃at the grain boundaries and another continuous at 350℃within the *** activation energy of the dissolution reaction of theβphase(mg_(17)Al_(12))under non-isothermal conditions is 116.781 kJ/mol,while it is 129.7383 kJ/mol under isothermal *** Avrami coefficient,n,relevant for the dissolution kinetics of theβphase(mg_(17)Al_(12))is 1.152 and 1.211 in the non-isothermal and isothermal conditions *** numerical coefficients m and Avrami n are 0.993 and 1.152.

关键词： AZ91 kinetics β(mg_(17)Al_(12)) Activation energy Discontinuous precipitation Continuous precipitation DSC

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