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On the 2-Domination Number of Complete Grid Graphs

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Open Journal of Discrete Mathematics 2017年第1期7卷 32-50页

作者： ramy shaheen Suhail Mahfud Khames Almanea Department of Mathematics Faculty of Science Tishreen University Lattakia Syria

A set D of vertices of a graph G = (V, E) is called k-dominating if every vertex v ∈V-D is adjacent to some k vertices of D. The k-domination number of a graph G, γk (G), is the order of a smallest k-dominating set of G. In this paper we calculate the k-domination number (for k = 2) of the product of two paths Pm × Pn for m = 1, 2, 3, 4, 5 and arbitrary n. These results were shown an error in the paper [1].

关键词： k-Dominating Set k-Domination Number 2-Dominating Set 2-Domination Number Cartesian Product Graphs Paths

Game Chromatic Number of Some Regular Graphs

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Open Journal of Discrete Mathematics 2019年第4期9卷 159-164页

作者： ramy shaheen Ziad Kanaya Khaled Alshehada Department of Mathematics Tishreen University Lattakia Syria

Let G be a graph and k be a positive integer. We consider a game with two players Alice and Bob who alternate in coloring the vertices of G with a set of k colors. In every turn, one vertex will be chosen by one player. Alice’s goal is to color all vertices with the k colors, while Bob’s goal is to prevent her. The game chromatic number denoted by?χg(G), is the smallest k such that Alice has a winning strategy with k colors. In this paper, we determine the game chromatic number?χg of circulant graphs?Cn(1,2), , and generalized Petersen graphs GP(n,2), GP(n,3).

关键词： Game Chromatic Number Circulant Graph Generalized Petersen Graphs

Domination and Eternal Domination of Jahangir Graph

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Open Journal of Discrete Mathematics 2019年第3期9卷 68-81页

作者： ramy shaheen Mohammad Assaad Ali Kassem Department of Mathematics Faculty of Science Tishreen University Lattakia Syria

In the eternal dominating set problem, guards form a dominating set on a graph and at each step, a vertex is attacked. We consider the “all guards move” of the eternal dominating set problem. In which one guard has to move to the attacked vertex and all the remaining guards are allowed to move to an adjacent vertex or stay in their current position after each attack. If the new formed set of guards is still a dominating set of the graph then we successfully defended the attack. Our goal is to find the minimum number of guards required to eternally protect the graph. We call this number the m-eternal domination number and we denote it by . In this paper we find the eternal domination number of Jahangir graph Js,m for s=2,3 and arbitrary m. We also find the domination number for J3,m .

关键词： Jahangir Graph Graph Protection Domination Number Eternal Domination

<i>d-Distance</i>Coloring of Generalized Petersen Graphs <i>P(n, k)</i>

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Open Journal of Discrete Mathematics 2017年第4期7卷 185-199页

作者： ramy shaheen Ziad Kanaya Samar Jakhlab Department of Mathematics Faculty of Science Tishreen University Lattakia Syria

A coloring of G is d-distance if any two vertices at distance at most d from each other get different colors. The minimum number of colors in d-distance colorings of G is its d-distance chromatic number, denoted by χd(G). In this paper, we give the exact value of χd(G) (d = 1, 2), for some types of generalized Petersen graphs P(n, k) where k = 1, 2, 3 and arbitrary n.

关键词： Distance Coloring Generalized Petersen Graphs

Effects of Moringa oleifera aqueous extract on the growth performance,blood characteristics,and histological features of gills and livers in Nile tilapia

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Aquaculture and Fisheries 2024年第1期9卷 85-92页

作者： Mahamoud A.Emam ramy M.Shourbela Waleed N.El-Hawarry Seham Y.Abo-Kora Fatma Abdel-Monem Gad Ashraf M.Abd El-latif Mahmoud A.O.Dawood Histology Department Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Department of Animal Husbandry and Animal Wealth Development Faculty of Veterinary MedicineAlexandria UniversityAlexandria22758Egypt Pharmacology Department Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Clinical Pathology Department Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Department of Aquatic Animal Diseases and Management Faculty of Veterinary MedicineBenha UniversityBenha13511Egypt Animal Production Department Faculty of AgricultureKafrelsheikh UniversityKafr El-Sheikh33511Egypt The Center for Applied Research on the Environment and Sustainability The American University in CairoCairo11835Egypt

Moringa oleifera is well known as a highly nutritious plant and a water purifier in fish *** fish has many impressive qualities making them very suitable for ***,this study aimed to evaluate the effect of supplementation of Moringa oleifera aqueous extract(MOAE)at varying concentrations(0,100,200,and 400 mg/kg diet for 90 days)on growth performance,hematological,and some biochemical parameters of Nile ***,histological changes and immunohistochemical expression of caspase 3 in gills and livers were *** enhancements(P<0.05)in the final weight,weight gain,specific growth rate,red blood cells,hemoglobin,packed cell volume,white blood cells,and total serum protein were observed in fish fed 200 mg MOAE/kg diet compared with other ***,a significant reduction(P<0.05)of liver and kidney function tests and non-significant changes in lipid profile were *** the other hand,fish fed 400 mg MOAE/kg diet revealed disturbance in the corresponding *** histological degenerative changes were detected in the gills and liver of fish fed 400 mg MOAE/kg *** comparison,fish fed 200 mg MOAE/kg diet showed the best histo-architectures of these organs compared with other *** immune expressions of caspase 3 were determined where gills and liver of fish fed 400 mg MOAE/kg diet revealed extensive number of positive caspase 3 cells indicating severe apoptotic ***,a dietary MOAE at 200 mg/kg diet is recommended to improve the growth performance,hematological parameters,liver and kidney functions in Nile ***,caution must be considered when using MOAE at a concentration over 200 mg/kg diet.

关键词： Growth performance Liver Gills Moringa oleifera Nile tilapia

Novel yellow colored flame compositions with superior spectral performance

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Defence Technology（防务技术） 2017年第1期13卷 33-39页

作者： ramy Sadek Mohamed Kassem Mohamed Abdo Sherif Elbasuney School of Chemical Engineering Military Technical CollegeKobry El-KobbaCairoEgypt

The production of colored flames is the primary purpose of military signaling, projectile tracing, and illuminating devices. Certain elements and compounds when heated to high temperature have the unique property of emitting lines or narrow bands in the visible region(380-780 nm). This study, reports on the development of novel yellow colored flame compositions with enhanced spectral performance in terms of luminous intensity, and color quality to standard Russian yellow tracer. The light intensity and the imprint spectra of developed yellow flares were measured using digital luxmeter and UV e Vis. spectrometer respectively. The main giving of this study is that the light intensity, and color quality of Russian yellow tracer were improved by 287%, and 170% respectively. This was accomplished by means of optimizing the ratio of novel binder to color source using aluminum metal fuel. Aluminumbased formulations were found to maximize the formation of yellow reactive emitting specimens, and to eliminate any interfering incandescent emission resulted from Mg O. Quantification of yellow color emitting specimens in the combustion gaseous products was achieved using chemical equilibrium thermodynamic code named ICT(Institute of Chemical Technology in Germany, Virgin 2008); in an attempt to judge the light quality. This improvement in yellow flare performance established the rule that the emission intensity increases as the reaction temperature increases. In the meantime upper limit of temperature was avoided to maximize the color quality.

关键词： Pyrotechnics Colored flames Yellow tracer Atomic spectroscopy Color quality

Spectrally adapted red flare tracers with superior spectral performance

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Defence Technology（防务技术） 2017年第6期13卷 406-412页

作者： ramy Sadek Mohamed Kassem Mohamed Abdo Sherif Elbasuney School of Chemical Engineering Military Technical CollegeKobry ElkobaCairoEgypt

The production of bright light, with vivid color, is the primary purpose of signaling, illuminating devices,and fire control purposes. This study, reports on the development of red flame compositions with enhanced performance in terms of luminous intensity, and color quality. The light intensity and the imprint spectra of developed red flame compositions to standard NATO red tracer(R-284 NATO) were measured using digital luxmeter, and UV-Vis. spectrometer. The main giving of this study is that the light intensity of standard NATO red tracer was increased by 72%, the color quality was also improved by60%(over the red band from 650 to 780 nm). This enhanced spectral performance was achieved by means of deriving the combustion process to maximize the formation of red color emitting species in the combustion flame. Thanks to the optimum ratio of color source to color intensifier using aluminum metal fuel; this approach offered the highest intensity and color quality. Upon combustion, aluminum was found to maximize the formation SrCL(the main reactive red color emitting species) and to minimize the interfering incandescent emission resulted from MgO and SrO. Quantification of active red color emitting species in the combustion flame was conducted using chemical equilibrium thermodynamic code named ICT. The improvement in red flare performance, established the rule that the color intensifier should be in the range from 10 to 15 Wt % of the total composition.

关键词： Pyrotechnics Colored flames Tracers Luminous intensity Molecular spectroscopy

Symmetry in optics and photonics:a group theory approach

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Science Bulletin 2018年第4期63卷 244-251页

作者： B.M.Rodriguez-Lara ramy EI-Ganainy Julio Guerrero Tecnologico de Monterrey.Escuela de Ingenieria y Ciencias Monterrey 64849Mexico Instituto Nacional de Astrofisica Optica y Electr6nicaPueblaCP 72840Mexico Department of Physics and Hexes Center for Quantum Phenomena Michigan Technological UniversityHoughton.MI 49931USA Departamento de Matematicas Facultad de Ciendas Experimentales y de la SaludCampus Las LagunillasUniversidad de Jaen23071JaenSpain Departamento de Ingenierfa y Tecnologia de Computadores Facultad de lnformdticaCampus EspinardoUnivesidad de Murcia30100 MurciaSpain

Group theory(GT) provides a rigorous framework for studying symmetries in various disciplines in physics ranging from quantum field theories and the standard model to fluid mechanics and chaos theory. To date, the application of such a powerful tool in optical physics remains limited. Over the past few years however, several quantum-inspired symmetry principles(such as parity-time invariance and supersymmetry) have been introduced in optics and photonics for the first time. Despite the intense activities in these new research directions, only few works utilized the power of group theory. Motivated by this status quo, here we present a brief overview of the application of GT in optics, deliberately choosing examples that illustrate the power of this tool in both continuous and discrete setups. We hope that this review will stimulate further research that exploits the full potential of GT for investigating various symmetry paradigms in optics, eventually leading to new photonic devices.

关键词： Group theoryHelmholtz equationDiscrete opticsParity-time (PT) symmetry

Denoising different types of acoustic partial discharge signals using power spectral subtraction

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High Voltage 2018年第1期3卷 44-50页

作者： ramy Hussein Khaled Bashir Shaban Ayman H.El-Hag Department of Electrical and Computer Engineering University of British ColumbiaVancouverBCCanada Department of Computer Science and Engineering Qatar UniversityDohaQatar Department of Electrical Engineering American University of SharjahSharjahUAE

Measuring acoustic emission(AE)of partial discharge(PD)phenomena can be adopted to estimate the condition of power ***,the environmental noise encountered with AE of PD measurements negatively affects the accuracy of PD localisation and ***,efficient signal denoising techniques are required for noise suppression and hence,better detection *** study deals with white noise and it is a continuation of a previously published work that deals with random *** published work addresses the random noise suppression using a method named,power spectral subtraction denoising(PSSD).This study applies PSSD to the PD signals contaminated with white noise and uses a novel scheme of noise power spectrum density *** types of AE signals are examined including signals produced by corona,surface,parallel,and void *** and real data demonstrate the superiority of the proposed method over the wavelet shrinkage denoising method as it can more effectively eliminate white noise and preserve signals of low signal-to-noise ratio.

关键词： power noise spectral