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Nonlinear theory of a Cherenkov free-electron laser

Research Abstract

Plasma fluid and Maxwell equations are used to derive an analytical expression for the high-gain of a Cherenkov Free-Electron Laser (FEL). The evolution of the gain from the linear to the non-linear regime is investigated. The gain expression is then generalized to predict the linear and non-linear effects at any stage of interaction, permitting us to identify the criteria of optimal design of Cherenkov FELs. In this study, the spatial dependence of the characterizing parameters of electron beam velocity and density, such as the average value and modulation amplitude, are considered. Also, the phase shift between the bunched electrons and the radiation field is taken into account. In the linear limit, it is shown that our gain expression agrees satisfactorily with those obtained in previous studies.

Research Authors
Hesham Fares
Mohamed Mahmoud
Research Department
Research Journal
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Research Member
Research Pages
1-7
Research Publisher
Hesham fares
Research Rank
1
Research Vol
976 - 164256
Research Website
https://www.sciencedirect.com/science/article/pii/S0168900220306525
Research Year
2020

Magnetohydrodynamic Mixed Convection and Entropy Analysis of Nanofluid in Gamma-Shaped Porous
Cavity.

Research Abstract

Magnetohydrodynamic Mixed Convection and Entropy Analysis of Nanofluid in Gamma-Shaped Porous
Cavity.

Research Authors
AJ.Chamkha,M.AMansour, AM.Rashad,H. Kargarsharifabad, TaherArmaghani
Research Department
Research Journal
Journal of Thermophysics and Heat Transfer,
Research Pages
p. 1-12.
Research Publisher
NULL
Research Rank
1
Research Vol
NULL
Research Website
NULL
Research Year
2020

Inclined magneto: convection, internal heat, and entropy generation of nanofluid in an I-shaped cavity saturated with porous media.

Research Abstract

Inclined magneto: convection, internal heat, and entropy generation of nanofluid in an I-shaped cavity saturated with porous media

Research Authors
T Armaghani, A Chamkha, A.M. Rashad, M.A. Mansour
Research Department
Research Journal
Journal of Thermal Analysis and Calorimetry,
Research Pages
p. 1-13.
Research Publisher
NULL
Research Rank
1
Research Vol
Research Website
NULL
Research Year
2020

Effect Of The Fractional Derivatives On Unsteady Natural Convection Of A Nanofluid In An Enclosure.

Research Abstract

Effect Of The Fractional Derivatives On Unsteady Natural Convection Of A Nanofluid In An Enclosure.

Research Authors
S.E. AHMED, M.A. MANSOUR, E. A-B. ABD-ELSALAM, E.F. MOHAMED,
Research Department
Research Journal
Latin American Applied Research
Research Pages
p. 13-19.
Research Publisher
NULL
Research Rank
1
Research Vol
50(1):
Research Website
NULL
Research Year
2020

Effects of the Caputo fractional derivatives on convective flow in wavy vented enclosures filled with a porous medium using Al2O3Cu hybrid nanofluids.

Research Abstract

Effects of the Caputo fractional derivatives on convective flow in wavy vented enclosures filled with a porous medium using Al2O3Cu hybrid nanofluids.

Research Authors
Sameh E. Ahmed, Mohamed A. Mansour , Emad A.B. Abdel Salam , Eman F. Mohamed,
Research Department
Research Journal
Heat Transfer
Research Pages
p. 1895-1919.
Research Publisher
NULL
Research Rank
1
Research Vol
49(4):
Research Website
NULL
Research Year
2020

, MHD mixed convection and entropy generation of nanofluid in a lid-driven U-shaped cavity with internal heat and partial slip

Research Abstract

MHD mixed convection and entropy generation of nanofluid in a lid-driven U-shaped cavity

Research Authors
AM Rashad, MA Mansour, T Armaghani, AJ Chamkha
Research Department
Research Journal
.Physics of Fluids
Research Pages
p. 042006.
Research Publisher
NULL
Research Rank
1
Research Vol
31(4):
Research Website
NULL
Research Year
2019

Entropy generation and nanofluid mixed convection in a C-shaped cavity with heat corner and inclined magnetic field.

Research Abstract

Entropy generation and nanofluid mixed convection in a C-shaped cavity

Research Authors
MA Mansour, T Armaghani, AJ Chamkha, AM Rashad
Research Department
Research Journal
The European Physical Journal Special Topics,
Research Pages
p. 2619-2645
Research Publisher
NULL
Research Rank
1
Research Vol
228(12):
Research Website
NULL
Research Year
2019

Studying the fractional derivative for natural convection in slanted cavity containing porous media

Research Abstract

NULL

Research Authors
Sameh E.Ahmed ,M.A.Mansour ,E.A.B.Abdel-Salam,Eman F.,Mohamed
Research Department
Research Journal
SN Applied Sciences
Research Pages
p 1117
Research Publisher
NULL
Research Rank
1
Research Vol
1(9)
Research Website
NULL
Research Year
2019

Analyzing the Energy Consumption of Sequential and Parallel Metaheuristics

Research Abstract

Real-life problems are usually time-consuming since they require solving large instances of NP-hard problems. Exact search methods in most of the cases cannot afford practical solutions for such problems. Metaheuristics arise as promising solvers for these problems, by obtaining acceptable solutions in terms of quality and computational cost in a reasonable time bound. Nowadays, energy efficiency is also taken into consideration during the design of new algorithms because of the million times that algorithms run on labs and computation centers. This work presents two novel experiments for investigating the numerical performance and energy efficiency of the sequential and parallel metaheuristics. The main aim of this study is to analyze the energy consumption of three well-known and commonly used metaheuristics (Genetic Algorithm, Variable Neighborhood Search, and Simulated Annealing) and their parallel versions. The discussions reveal the differences/similarities between the different sequential/parallel algorithms, which include trajectory-based and population-based metaheuristics so that this study is useful for the future design of energy-aware algorithms.

Research Authors
Amr Abdelhafez ; Gabriel Luque ; Enrique Alba
Research Journal
2019 International Conference on High Performance Computing & Simulation (HPCS)
Research Pages
NULL
Research Publisher
IEEE
Research Rank
3
Research Vol
NULL
Research Website
https://doi.org/10.1109/HPCS48598.2019.9188170
Research Year
2019
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